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/*
* Copyright (c) 1985, 1989 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that: (1) source distributions retain this entire copyright
* notice and comment, and (2) distributions including binaries display
* the following acknowledgement: ``This product includes software
* developed by the University of California, Berkeley and its contributors''
* in the documentation or other materials provided with the distribution
* and in all advertising materials mentioning features or use of this
* software. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/*
* Originally, this program came from Rutgers University, however it
* is based on nslookup and other pieces of named tools, so it needs
* that copyright notice.
*/
/*
* Rewritten by Eric Wassenaar, Nikhef-H, <e07@nikhef.nl>
*
* The officially maintained source of this program is available
* via anonymous ftp from machine 'ftp.nikhef.nl' [192.16.199.1]
* in the directory '/pub/network' as 'host.tar.Z'
*
* You are kindly requested to report bugs and make suggestions
* for improvements to the author at the given email address,
* and to not re-distribute your own modifications to others.
*/
#ifndef lint
static char Version[] = "@(#)host.c e07@nikhef.nl (Eric Wassenaar) 951231";
#endif
#if defined(apollo) && defined(lint)
#define __attribute(x)
#endif
#define justfun /* this is only for fun */
#undef obsolete /* old code left as a reminder */
#undef notyet /* new code for possible future use */
/*
* New features
*
* - Major overhaul of the entire code.
* - Very rigid error checking, with more verbose error messages.
* - Zone listing section completely rewritten.
* - It is now possible to do recursive listings into delegated zones.
* - Maintain resource record statistics during zone listings.
* - Maintain count of hosts during zone listings.
* - Check for various extraneous conditions during zone listings.
* - Check for illegal domain names containing invalid characters.
* - Verify that certain domain names represent canonical host names.
* - Perform ttl consistency checking during zone listings.
* - Exploit multiple server addresses if available.
* - Option to exploit only primary server for zone transfers.
* - Option to exclude info from names that do not reside in a zone.
* - Implement timeout handling during connect and read.
* - Write resource record output to optional log file.
* - Special MB tracing by recursively expanding MR and MG records.
* - Special mode to check SOA records at each nameserver for a zone.
* - Special mode to check reverse mappings of host addresses.
* - Extended syntax allows multiple arguments on command line or stdin.
* - Configurable default options in HOST_DEFAULTS environment variable.
* - Implement new resource record types from RFC 1183 and 1348.
* - Basic experimental NSAP support as defined in RFC 1637.
* - Implement new resource record types from RFC 1664 and 1712.
* - Code is extensively documented.
*/
/*
* Publication history
*
* This information has been moved to the RELEASE_NOTES file.
*/
/*
* Compilation options
*
* This program usually compiles without special compilation options,
* but for some platforms you may have to define special settings.
* See the Makefile and the header file port.h for details.
*/
/*
* Miscellaneous notes
*
* This program should be linked explicitly with the BIND resolver library
* in case the default gethostbyname() or gethostbyaddr() routines use a
* non-standard strategy for retrieving information. These functions in the
* resolver library call on the nameserver, and fall back on the hosts file
* only if no nameserver is running (ECONNREFUSED).
*
* You may also want to link this program with the BIND resolver library if
* your default library has not been compiled with DEBUG printout enabled.
*
* The version of the resolver should be BIND 4.8.2 or later. The crucial
* include files are <netdb.h>, (resolv.h>, <arpa/nameser.h>. These files
* are assumed to be present in the /usr/include directory.
*
* The resolver code depends on the definition of the BSD pre-processor
* variable. This variable is usually defined in the file <sys/param.h>.
*
* The definition of this variable determines the method how to handle
* datagram connections. This may not work properly on all platforms.
*
* The hostent struct defined in <netdb.h> is assumed to handle multiple
* addresses in h_addr_list[]. Usually this is true if BSD >= 43.
*
* Your nameserver may not handle queries about top-level zones properly
* if the "domain" directive is present in the named.boot file. It will
* append the default domain to single names for which no data is cached.
*
* The treatment of TXT records has changed from 4.8.2 to 4.8.3. Formerly,
* the data consisted simply of the text string. Now, the text string is
* preceded by the character count with a maximum of 255, and multiple
* strings are embedded if the total character count exceeds 255.
* We handle only the new situation in this program, assuming that nobody
* uses TXT records before 4.8.3 (unfortunately this is not always true:
* current vendor supplied software may sometimes be even pre-BIND 4.8.2).
*
* Note that in 4.8.3 PACKETSZ from nameser.h is still at 512, which is
* the maximum possible packet size for datagrams, whereas MAXDATA from
* db.h has increased from 256 to 2048. The resolver defines MAXPACKET
* as 1024. The nameserver reads queries in a buffer of size BUFSIZ.
*
* The gethostbyname() routine in 4.8.3 interprets dotted quads (if not
* terminated with a dot) and simulates a gethostbyaddr(), but we will
* not rely on it, and handle dotted quads ourselves.
*
* On some systems a bug in the _doprnt() routine exists which prevents
* printf("%.*s", n, string) to be printed correctly if n == 0.
*
* This program has not been optimized for speed. Especially the memory
* management is simple and straightforward.
*/
/*
* Terminology used
*
* Gateway hosts.
* These are hosts that have more than one address registered under
* the same name. Obviously we cannot recognize a gateway host if it
* has different names associated with its different addresses.
*
* Duplicate hosts.
* These are non-gateway hosts of which the address was found earlier
* but with a different name, possibly in a totally different zone.
* Such hosts should not be counted again in the overall host count.
* This situation notably occurs in e.g. the "ac.uk" domain which has
* many names registered in both the long and the abbreviated form,
* such as 'host.department.university.ac.uk' and 'host.dept.un.ac.uk'.
* This is probably not an error per se. It is an error if some domain
* has registered a foreign address under a name within its own domain.
* To recognize duplicate hosts when traversing many zones, we have to
* maintain a global list of host addresses. To simplify things, only
* single-address hosts are handled as such.
*
* Extrazone hosts.
* These are hosts which belong to a zone but which are not residing
* directly within the zone under consideration and which are not
* glue records for a delegated zone of the given zone. E.g. if we are
* processing the zone 'bar' and find 'host.foo.bar' but 'foo.bar' is not
* an NS registered delegated zone of 'bar' then it is considered to be
* an extrazone host. This is not necessarily an error, but it could be.
*
* Lame delegations.
* If we query the SOA record of a zone at a supposedly authoritative
* nameserver for that zone (listed in the NS records for the zone),
* the SOA record should be present and the answer authoritative.
* If not, we flag a lame delegation of the zone to that nameserver.
* This may need refinement in some special cases.
* A lame delegation is also flagged if we discover that a nameserver
* mentioned in an NS record does not exist when looking up its address.
*
* Primary nameserver.
* This utility assumes that the first domain name in the RHS of the
* SOA record for a zone contains the name of the primary nameserver
* (or one of the primary nameservers) for that zone. Unfortunately,
* this field has not been unambiguously defined. Nevertheless, many
* hostmasters interpret the definitions given in RFC 1033 and 1035
* as such, and therefore host will continue doing so. Interpretation
* as the machine that holds the zone data disk file is pretty useless.
*/
/*
* Usage: host [options] name [server]
* Usage: host [options] -x [name ...]
* Usage: host [options] -X server [name ...]
*
* Regular command line options:
* ----------------------------
*
* -t type specify query type; default is T_A for normal mode
* -a specify query type T_ANY
* -v print verbose messages (-vv is very verbose)
* -d print debugging output (-dd prints even more)
*
* Special mode options.
* --------------------
*
* -l special mode to generate zone listing for a zone
* -L level do recursive zone listing/checking this level deep
* -p use primary nameserver of zone for zone transfers
* -P server give priority to preferred servers for zone transfers
* -N zone do not perform zone transfer for these explicit zones
* -S print zone resource record statistics
* -H special mode to count hosts residing in a zone
* -G same as -H but lists gateway hosts in addition
* -E same as -H but lists extrazone hosts in addition
* -D same as -H but lists duplicate hosts in addition
* -C special mode to check SOA records for a zone
* -A special mode to check reverse mappings of host addresses
*
* Miscellaneous options.
* ---------------------
*
* -f filename log resource record output also in given file
* -F filename same as -f, but exchange role of stdout and log file
* -I chars chars are not considered illegal in domain names
* -i generate reverse in-addr.arpa query for dotted quad
* -n generate reverse nsap.int query for dotted nsap address
* -q be quiet about some non-fatal errors
* -T print ttl value during non-verbose output
* -Z print selected RR output in full zone file format
*
* Seldom used options.
* -------------------
*
* -c class specify query class; default is C_IN
* -e exclude info from names that do not reside in the zone
* -m specify query type T_MAILB and trace MB records
* -o suppress resource record output to stdout
* -r do not use recursion when querying nameserver
* -R repeatedly add search domains to qualify queryname
* -s secs specify timeout value in seconds; default is 2 * 5
* -u use virtual circuit instead of datagram for queries
* -w wait until nameserver becomes available
*
* Undocumented options. (Experimental, subject to change)
* --------------------
*
* -g length only select names that are at least this long
* -B enforce full BIND behavior during DNSRCH
* -M special mode to list mailable delegated zones of zone
* -W special mode to list wildcard records in a zone
* -z special mode to list delegated zones in a zone
*/
static char Usage[] =
"\
Usage: host [-v] [-a] [-t querytype] [options] name [server]\n\
Listing: host [-v] [-a] [-t querytype] [options] -l zone [server]\n\
Hostcount: host [-v] [options] -H [-D] [-E] [-G] zone\n\
Check soa: host [-v] [options] -C zone\n\
Addrcheck: host [-v] [options] -A host\n\
Listing options: [-L level] [-S] [-A] [-p] [-P prefserver] [-N skipzone]\n\
Common options: [-d] [-f|-F filename] [-I chars] [-i|-n] [-q] [-T] [-Z]\n\
Other options: [-c class] [-e] [-m] [-o] [-r] [-R] [-s secs] [-u] [-w]\n\
Extended usage: [-x [name ...]] [-X server [name ...]]\
";
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <netdb.h>
#include <sys/types.h> /* not always automatically included */
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#undef NOERROR /* in <sys/streams.h> on solaris 2.x */
#include <arpa/nameser.h>
#include <resolv.h>
#include "port.h" /* various portability definitions */
#include "conf.h" /* various configuration definitions */
#include "type.h" /* types should be in <arpa/nameser.h> */
#include "exit.h" /* exit codes come from <sysexits.h> */
typedef int bool; /* boolean type */
#define TRUE 1
#define FALSE 0
#ifndef NO_DATA
#define NO_DATA NO_ADDRESS /* used here only in case authoritative */
#endif
#define NO_RREC (NO_DATA + 1) /* used for non-authoritative NO_DATA */
#define NO_HOST (NO_DATA + 2) /* used for non-authoritative HOST_NOT_FOUND */
#define QUERY_REFUSED (NO_DATA + 3) /* query was refused by server */
#define SERVER_FAILURE (NO_DATA + 4) /* instead of TRY_AGAIN upon SERVFAIL */
#define HOST_NOT_CANON (NO_DATA + 5) /* host name is not canonical */
#define T_NONE 0 /* yet unspecified resource record type */
#define T_FIRST T_A /* first possible type in resource record */
#define T_LAST (T_AXFR - 1) /* last possible type in resource record */
#ifndef NOCHANGE
#define NOCHANGE 0xf /* compatibility with older BIND versions */
#endif
#define NOT_DOTTED_QUAD ((ipaddr_t)-1)
#define BROADCAST_ADDR ((ipaddr_t)0xffffffff)
#define LOCALHOST_ADDR ((ipaddr_t)0x7f000001)
#if PACKETSZ > 1024
#define MAXPACKET PACKETSZ
#else
#define MAXPACKET 1024
#endif
typedef union {
HEADER header;
u_char packet[MAXPACKET];
} querybuf;
#ifndef HFIXEDSZ
#define HFIXEDSZ 12 /* actually sizeof(HEADER) */
#endif
#define MAXDLEN (MAXPACKET - HFIXEDSZ) /* upper bound for dlen */
#include "rrec.h" /* resource record structures */
#define input /* read-only input parameter */
#define output /* modified output parameter */
#define STDIN 0
#define STDOUT 1
#define STDERR 2
#ifdef lint
#define EXTERN
#else
#define EXTERN extern
#endif
EXTERN int errno;
EXTERN int h_errno; /* defined in gethostnamadr.c */
EXTERN res_state_t _res; /* defined in res_init.c */
extern char *dbprefix; /* prefix for debug messages (send.c) */
extern char *version; /* program version number (vers.c) */
char **optargv = NULL; /* argument list including default options */
int optargc = 0; /* number of arguments in new argument list */
int errorcount = 0; /* global error count */
int record_stats[T_ANY+1]; /* count of resource records per type */
char cnamebuf[MAXDNAME+1];
char *cname = NULL; /* name to which CNAME is aliased */
char mnamebuf[MAXDNAME+1];
char *mname = NULL; /* name to which MR or MG is aliased */
char soanamebuf[MAXDNAME+1];
char *soaname = NULL; /* domain name of SOA record */
char subnamebuf[MAXDNAME+1];
char *subname = NULL; /* domain name of NS record */
char adrnamebuf[MAXDNAME+1];
char *adrname = NULL; /* domain name of A record */
ipaddr_t address; /* internet address of A record */
char *listhost = NULL; /* actual host queried during zone listing */
char serverbuf[MAXDNAME+1];
char *server = NULL; /* name of explicit server to query */
char realnamebuf[2*MAXDNAME+2];
char *realname = NULL; /* the actual name that was queried */
FILE *logfile = NULL; /* default is stdout only */
bool logexchange = FALSE; /* exchange role of log file and stdout */
char *illegal = NULL; /* give warning about illegal domain names */
char *skipzone = NULL; /* zone(s) for which to skip zone transfer */
char *prefserver = NULL; /* preferred server(s) for zone listing */
char *queryname = NULL; /* the name about which to query */
int querytype = T_NONE; /* the type of the query */
int queryclass = C_IN; /* the class of the query */
ipaddr_t queryaddr; /* set if name to query is dotted quad */
int debug = 0; /* print resolver debugging output */
int verbose = 0; /* verbose mode for extra output */
#ifdef justfun
int namelen = 0; /* select records exceeding this length */
#endif
int recursive = 0; /* recursive listmode maximum level */
int recursion_level = 0; /* current recursion level */
int skip_level = 0; /* level beyond which to skip checks */
bool quiet = FALSE; /* suppress non-fatal warning messages */
bool reverse = FALSE; /* generate reverse in-addr.arpa queries */
bool revnsap = FALSE; /* generate reverse nsap.int queries */
bool primary = FALSE; /* use primary server for zone transfers */
bool suppress = FALSE; /* suppress resource record output */
bool dotprint = FALSE; /* print trailing dot in non-listing mode */
bool ttlprint = FALSE; /* print ttl value in non-verbose mode */
bool waitmode = FALSE; /* wait until server becomes available */
bool mailmode = FALSE; /* trace MG and MR into MB records */
bool addrmode = FALSE; /* check reverse mappings of addresses */
bool listmode = FALSE; /* generate zone listing of a zone */
bool hostmode = FALSE; /* count real hosts residing within zone */
bool duplmode = FALSE; /* list duplicate hosts within zone */
bool extrmode = FALSE; /* list extrazone hosts within zone */
bool gatemode = FALSE; /* list gateway hosts within zone */
bool checkmode = FALSE; /* check SOA records at each nameserver */
bool mxdomains = FALSE; /* list MX records for each delegated zone */
bool wildcards = FALSE; /* list only wildcard records in a zone */
bool listzones = FALSE; /* list only delegated zones in a zone */
bool exclusive = FALSE; /* exclude records that are not in zone */
bool recurskip = FALSE; /* skip certain checks during recursion */
bool statistics = FALSE; /* print resource record statistics */
bool bindcompat = FALSE; /* enforce full BIND DNSRCH compatibility */
bool classprint = FALSE; /* print class value in non-verbose mode */
#include "defs.h" /* declaration of functions */
#define lower(c) (((c) >= 'A' && (c) <= 'Z') ? (c) + 'a' - 'A' : (c))
#define hexdigit(n) (((n) < 10) ? '0' + (n) : 'A' + (n) - 10);
#define is_xdigit(c) (isascii(c) && isxdigit(c))
#define is_space(c) (isascii(c) && isspace(c))
#define is_alnum(c) (isascii(c) && isalnum(c))
#define is_upper(c) (isascii(c) && isupper(c))
#define bitset(a,b) (((a) & (b)) != 0)
#define sameword(a,b) (strcasecmp(a,b) == 0)
#define samepart(a,b) (strncasecmp(a,b,strlen(b)) == 0)
#define samehead(a,b) (strncasecmp(a,b,sizeof(b)-1) == 0)
#define fakename(a) (samehead(a,"localhost.") || samehead(a,"loopback."))
#define nulladdr(a) (((a) == 0) || ((a) == BROADCAST_ADDR))
#define fakeaddr(a) (nulladdr(a) || ((a) == htonl(LOCALHOST_ADDR)))
#define incopy(a) *((struct in_addr *)a)
#define newlist(a,n,t) (t *)xalloc((ptr_t *)a, (siz_t)((n)*sizeof(t)))
#define newstring(s) (char *)xalloc((ptr_t *)NULL, (siz_t)(strlen(s)+1))
#define newstr(s) strcpy(newstring(s), s)
#define xfree(a) (void) free((ptr_t *)a)
#define strlength(s) (int)strlen(s)
#define in_string(s,c) (index(s,c) != NULL)
#define plural(n) (((n) == 1) ? "" : "s")
#define plurale(n) (((n) == 1) ? "" : "es")
#ifdef DEBUG
#define assert(condition)\
{\
if (!(condition))\
{\
(void) fprintf(stderr, "assertion botch: ");\
(void) fprintf(stderr, "%s(%d): ", __FILE__, __LINE__);\
(void) fprintf(stderr, "%s\n", "condition");\
exit(EX_SOFTWARE);\
}\
}
#else
#define assert(condition)
#endif
/*
** MAIN -- Start of program host
** -----------------------------
**
** Exits:
** EX_OK Operation successfully completed
** EX_UNAVAILABLE Could not obtain requested information
** EX_CANTCREAT Could not create specified log file
** EX_NOINPUT No input arguments were found
** EX_NOHOST Could not lookup explicit server
** EX_OSERR Could not obtain resources
** EX_USAGE Improper parameter/option specified
** EX_SOFTWARE Assertion botch in DEBUG mode
*/
int
main(argc, argv)
input int argc;
input char *argv[];
{
register char *option;
res_state_t new_res; /* new resolver database */
int result; /* result status of action taken */
char *program; /* name that host was called with */
char *servername = NULL; /* name of explicit server */
char *logfilename = NULL; /* name of log file */
bool extended = FALSE; /* accept extended argument syntax */
assert(sizeof(int) >= 4); /* probably paranoid */
#ifdef obsolete
assert(sizeof(u_short) == 2); /* perhaps less paranoid */
assert(sizeof(ipaddr_t) == 4); /* but this is critical */
#endif
/*
* Synchronize stdout and stderr in case output is redirected.
*/
linebufmode(stdout);
/*
* Initialize resolver, set new defaults. See show_res() for details.
* The old defaults are (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH)
*/
(void) res_init();
_res.options |= RES_DEFNAMES; /* qualify single names */
_res.options &= ~RES_DNSRCH; /* dotted names are qualified */
_res.options |= RES_RECURSE; /* request nameserver recursion */
_res.options &= ~RES_DEBUG; /* turn off debug printout */
_res.options &= ~RES_USEVC; /* do not use virtual circuit */
_res.retry = 2; /* number of retries, default = 4 */
_res.retrans = 5; /* timeout in seconds, default = 5 or 6 */
/* initialize packet id */
_res.id = getpid() & 0x7fff;
/* save new defaults */
new_res = _res;
/*
* Check whether host was called with a different name.
* Interpolate default options and parameters.
*/
if (argc < 1 || argv[0] == NULL)
fatal(Usage);
option = getenv("HOST_DEFAULTS");
if (option != NULL)
{
set_defaults(option, argc, argv);
argc = optargc; argv = optargv;
}
program = rindex(argv[0], '/');
if (program++ == NULL)
program = argv[0];
/* check for resource record names */
querytype = parse_type(program);
if (querytype < 0)
querytype = T_NONE;
/* check for zone listing abbreviation */
if (sameword(program, "zone"))
listmode = TRUE;
/*
* Scan command line options and flags.
*/
while (argc > 1 && argv[1] != NULL && argv[1][0] == '-')
{
for (option = &argv[1][1]; *option != '\0'; option++)
{
switch (*option)
{
case 'w' :
waitmode = TRUE;
new_res.retry = 2;
new_res.retrans = 5;
break;
case 's' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing timeout value");
new_res.retry = 2;
new_res.retrans = atoi(argv[2]);
if (new_res.retrans <= 0)
fatal("Invalid timeout value %s", argv[2]);
argv++; argc--;
break;
case 'r' :
new_res.options &= ~RES_RECURSE;
break;
case 'B' :
bindcompat = TRUE;
/*FALLTHROUGH*/
case 'R' :
new_res.options |= RES_DNSRCH;
break;
case 'u' :
new_res.options |= RES_USEVC;
break;
case 'd' :
new_res.options |= RES_DEBUG;
debug++; /* increment debugging level */
break;
case 'v' :
verbose++; /* increment verbosity level */
break;
case 'q' :
quiet = TRUE;
break;
case 'i' :
reverse = TRUE;
break;
case 'n' :
revnsap = TRUE;
break;
case 'p' :
primary = TRUE;
break;
case 'o' :
suppress = TRUE;
break;
case 'e' :
exclusive = TRUE;
break;
case 'S' :
statistics = TRUE;
break;
case 'T' :
ttlprint = TRUE;
break;
case 'Z' :
dotprint = TRUE;
ttlprint = TRUE;
classprint = TRUE;
break;
case 'A' :
addrmode = TRUE;
break;
case 'D' :
case 'E' :
case 'G' :
case 'H' :
if (*option == 'D')
duplmode = TRUE;
if (*option == 'E')
extrmode = TRUE;
if (*option == 'G')
gatemode = TRUE;
hostmode = TRUE;
listmode = TRUE;
if (querytype == T_NONE)
querytype = -1; /* suppress zone data output */
break;
case 'C' :
checkmode = TRUE;
listmode = TRUE;
if (querytype == T_NONE)
querytype = -1; /* suppress zone data output */
break;
case 'z' :
listzones = TRUE;
listmode = TRUE;
if (querytype == T_NONE)
querytype = -1; /* suppress zone data output */
break;
case 'M' :
mxdomains = TRUE;
listmode = TRUE;
if (querytype == T_NONE)
querytype = -1; /* suppress zone data output */
break;
case 'W' :
wildcards = TRUE;
listmode = TRUE;
if (querytype == T_NONE)
querytype = T_MX;
break;
case 'L' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing recursion level");
recursive = atoi(argv[2]);
if (recursive <= 0)
fatal("Invalid recursion level %s", argv[2]);
argv++; argc--;
/*FALLTHROUGH*/
case 'l' :
listmode = TRUE;
break;
case 'c' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing query class");
queryclass = parse_class(argv[2]);
if (queryclass < 0)
fatal("Invalid query class %s", argv[2]);
argv++; argc--;
break;
case 't' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing query type");
querytype = parse_type(argv[2]);
if (querytype < 0)
fatal("Invalid query type %s", argv[2]);
argv++; argc--;
break;
case 'a' :
querytype = T_ANY; /* filter anything available */
break;
case 'm' :
mailmode = TRUE;
querytype = T_MAILB; /* filter MINFO/MG/MR/MB data */
break;
case 'I' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing allowed chars");
illegal = argv[2];
argv++; argc--;
break;
case 'P' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing preferred server");
prefserver = argv[2];
argv++; argc--;
break;
case 'N' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing zone to be skipped");
skipzone = argv[2];
argv++; argc--;
break;
case 'F' :
logexchange = TRUE;
/*FALLTHROUGH*/
case 'f' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing log file name");
logfilename = argv[2];
argv++; argc--;
break;
case 'X' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing server name");
servername = argv[2];
argv++; argc--;
/*FALLTHROUGH*/
case 'x' :
extended = TRUE;
break;
#ifdef justfun
case 'g' :
if (argv[2] == NULL || argv[2][0] == '-')
fatal("Missing minimum length");
namelen = atoi(argv[2]);
if (namelen <= 0)
fatal("Invalid minimum length %s", argv[2]);
argv++; argc--;
break;
#endif
case 'V' :
printf("Version %s\n", version);
exit(EX_OK);
default:
fatal(Usage);
}
}
argv++; argc--;
}
/*
* Check the remaining arguments.
*/
/* old syntax must have at least one argument */
if (!extended && (argc < 2 || argv[1] == NULL || argc > 3))
fatal(Usage);
/* old syntax has explicit server as second argument */
if (!extended && (argc > 2 && argv[2] != NULL))
servername = argv[2];
/*
* Open log file if requested.
*/
if (logfilename != NULL)
set_logfile(logfilename);
/*
* Set default preferred server for zone listings, if not specified.
*/
if (listmode && (prefserver == NULL))
prefserver = myhostname();
/*
* Check for possible alternative server. Use new resolver defaults.
*/
if (servername != NULL)
set_server(servername);
/*
* Do final resolver initialization.
* Show resolver parameters and special environment options.
*/
/* set new resolver values changed by command options */
_res.retry = new_res.retry;
_res.retrans = new_res.retrans;
_res.options = new_res.options;
/* show the new resolver database */
if (debug > 1 || verbose > 1)
show_res();
/* show customized default domain */
option = getenv("LOCALDOMAIN");
if (option != NULL && verbose > 1)
printf("Explicit local domain %s\n\n", option);
/*
* Process command line argument(s) depending on syntax.
*/
if (!extended) /* only one argument */
result = process_name(argv[1]);
else if (argc < 2) /* no arguments */
result = process_file(stdin);
else /* multiple command line arguments */
result = process_argv(argc, argv);
/*
* Report result status of action taken.
*/
exit(result);
/*NOTREACHED*/
}
/*
** SET_DEFAULTS -- Interpolate default options and parameters in argv
** ------------------------------------------------------------------
**
** The HOST_DEFAULTS environment variable gives customized options.
**
** Returns:
** None.
**
** Outputs:
** Creates ``optargv'' vector with ``optargc'' arguments.
*/
void
set_defaults(option, argc, argv)
input char *option; /* option string */
input int argc; /* original command line arg count */
input char *argv[]; /* original command line arguments */
{
register char *p, *q;
register int i;
/*
* Allocate new argument vector.
*/
optargv = newlist(NULL, 2, char *);
optargv[0] = argv[0];
optargc = 1;
/*
* Construct argument list from option string.
*/
for (q = "", p = newstr(option); *p != '\0'; p = q)
{
while (is_space(*p))
p++;
if (*p == '\0')
break;
for (q = p; *q != '\0' && !is_space(*q); q++)
continue;
if (*q != '\0')
*q++ = '\0';
optargv = newlist(optargv, optargc+2, char *);
optargv[optargc] = p;
optargc++;
}
/*
* Append command line arguments.
*/
for (i = 1; i < argc && argv[i] != NULL; i++)
{
optargv = newlist(optargv, optargc+2, char *);
optargv[optargc] = argv[i];
optargc++;
}
/* and terminate */
optargv[optargc] = NULL;
}
/*
** PROCESS_ARGV -- Process command line arguments
** ----------------------------------------------
**
** Returns:
** EX_OK if information was obtained successfully.
** Appropriate exit code otherwise.
*/
int
process_argv(argc, argv)
input int argc;
input char *argv[];
{
register int i;
int result; /* result status of action taken */
int excode = EX_NOINPUT; /* overall result status */
for (i = 1; i < argc && argv[i] != NULL; i++)
{
/* process a single argument */
result = process_name(argv[i]);
/* maintain overall result */
if (result != EX_OK || excode == EX_NOINPUT)
excode = result;
}
/* return overall result */
return(excode);
}
/*
** PROCESS_FILE -- Process arguments from input file
** -------------------------------------------------
**
** Returns:
** EX_OK if information was obtained successfully.
** Appropriate exit code otherwise.
*/
int
process_file(fp)
input FILE *fp; /* input file with query names */
{
register char *p, *q;
char buf[BUFSIZ];
int result; /* result status of action taken */
int excode = EX_NOINPUT; /* overall result status */
while (fgets(buf, sizeof(buf), fp) != NULL)
{
p = index(buf, '\n');
if (p != NULL)
*p = '\0';
/* extract names separated by whitespace */
for (q = "", p = buf; *p != '\0'; p = q)
{
while (is_space(*p))
p++;
/* ignore comment lines */
if (*p == '\0' || *p == '#' || *p == ';')
break;
for (q = p; *q != '\0' && !is_space(*q); q++)
continue;
if (*q != '\0')
*q++ = '\0';
/* process a single argument */
result = process_name(p);
/* maintain overall result */
if (result != EX_OK || excode == EX_NOINPUT)
excode = result;
}
}
/* return overall result */
return(excode);
}
/*
** PROCESS_NAME -- Process a single command line argument
** ------------------------------------------------------
**
** Returns:
** EX_OK if information was obtained successfully.
** Appropriate exit code otherwise.
**
** Wrapper for execute_name() to hide administrative tasks.
*/
int
process_name(name)
input char *name; /* command line argument */
{
int result; /* result status of action taken */
static int save_querytype;
static bool save_reverse;
static bool firstname = TRUE;
/* separate subsequent pieces of output */
if (!firstname && (verbose || debug || checkmode))
printf("\n");
/*
* Some global variables are redefined further on. Save their initial
* values in the first pass, and restore them during subsequent passes.
*/
if (firstname)
{
save_querytype = querytype;
save_reverse = reverse;
firstname = FALSE;
}
else
{
querytype = save_querytype;
reverse = save_reverse;
}
/*
* Do the real work.
*/
result = execute_name(name);
return(result);
}
/*
** EXECUTE_NAME -- Process a single command line argument
** ------------------------------------------------------
**
** Returns:
** EX_OK if information was obtained successfully.
** Appropriate exit code otherwise.
**
** Outputs:
** Defines ``queryname'' and ``queryaddr'' appropriately.
**
** Side effects:
** May redefine ``querytype'' and ``reverse'' if necessary.
*/
int
execute_name(name)
input char *name; /* command line argument */
{
bool result; /* result status of action taken */
/* check for nonsense input name */
if (strlength(name) > MAXDNAME)
{
errmsg("Query name %s too long", name);
return(EX_USAGE);
}
/*
* Analyze the name and type to be queried about.
* The name can be an ordinary domain name, or an internet address
* in dotted quad notation. If the -n option is given, the name is
* supposed to be a dotted nsap address.
*/
queryname = name;
if (queryname[0] == '\0')
queryname = ".";
if (sameword(queryname, "."))
queryaddr = NOT_DOTTED_QUAD;
else
queryaddr = inet_addr(queryname);
/*
* Generate reverse in-addr.arpa query if so requested.
* The input name must be a dotted quad, and be convertible.
*/
if (reverse)
{
if (queryaddr == NOT_DOTTED_QUAD)
name = queryname, queryname = NULL;
else
queryname = in_addr_arpa(queryname);
if (queryname == NULL)
{
errmsg("Invalid dotted quad %s", name);
return(EX_USAGE);
}
queryaddr = NOT_DOTTED_QUAD;
}
/*
* Generate reverse nsap.int query if so requested.
* The input name must be a dotted nsap, and be convertible.
*/
if (revnsap)
{
if (reverse)
name = queryname, queryname = NULL;
else
queryname = nsap_int(queryname);
if (queryname == NULL)
{
errmsg("Invalid nsap address %s", name);
return(EX_USAGE);
}
queryaddr = NOT_DOTTED_QUAD;
reverse = TRUE;
}
/*
* In regular mode, the querytype is used to formulate the nameserver
* query, and any response is filtered out when processing the answer.
* In listmode, the querytype is used to filter out the proper records.
*/
/* set querytype for regular mode if unspecified */
if ((querytype == T_NONE) && !listmode)
{
if ((queryaddr != NOT_DOTTED_QUAD) || reverse)
querytype = T_PTR;
else
querytype = T_A;
}
/*
* Check for incompatible options.
*/
/* cannot have dotted quad in listmode */
if (listmode && (queryaddr != NOT_DOTTED_QUAD))
{
errmsg("Invalid query name %s", queryname);
return(EX_USAGE);
}
/* must have regular name or dotted quad in addrmode */
if (!listmode && addrmode && reverse)
{
errmsg("Invalid query name %s", queryname);
return(EX_USAGE);
}
/* show what we are going to query about */
if (verbose)
show_types(queryname, querytype, queryclass);
/*
* All set. Perform requested function.
*/
result = execute(queryname, queryaddr);
return(result ? EX_OK : EX_UNAVAILABLE);
}
/*
** EXECUTE -- Perform the requested function
** -----------------------------------------
**
** Returns:
** TRUE if information was obtained successfully.
** FALSE otherwise.
**
** The whole environment has been set up and checked.
*/
bool
execute(name, addr)
input char *name; /* name to query about */
input ipaddr_t addr; /* explicit address of query */
{
bool result; /* result status of action taken */
/*
* Special mode to list contents of specified zone.
*/
if (listmode)
{
result = list_zone(name);
return(result);
}
/*
* Special mode to check reverse mappings of host addresses.
*/
if (addrmode)
{
if (addr == NOT_DOTTED_QUAD)
result = check_addr(name);
else
result = check_name(addr);
return(result);
}
/*
* Regular mode to query about specified host.
*/
result = host_query(name, addr);
return(result);
}
/*
** HOST_QUERY -- Regular mode to query about specified host
** --------------------------------------------------------
**
** Returns:
** TRUE if information was obtained successfully.
** FALSE otherwise.
*/
bool
host_query(name, addr)
input char *name; /* name to query about */
input ipaddr_t addr; /* explicit address of query */
{
struct hostent *hp;
struct in_addr inaddr;
char newnamebuf[MAXDNAME+1];
char *newname = NULL; /* name to which CNAME is aliased */
int ncnames = 0; /* count of CNAMEs in chain */
bool result; /* result status of action taken */
inaddr.s_addr = addr;
result = FALSE;
h_errno = TRY_AGAIN;
/* retry until positive result or permanent failure */
while (result == FALSE && h_errno == TRY_AGAIN)
{
/* reset before each query to avoid stale data */
errno = 0;
realname = NULL;
if (addr == NOT_DOTTED_QUAD)
{
/* reset CNAME indicator */
cname = NULL;
/* lookup the name in question */
if (newname == NULL)
result = get_hostinfo(name, FALSE);
else
result = get_hostinfo(newname, TRUE);
/* recurse on CNAMEs, but not too deep */
if (cname && (querytype != T_CNAME))
{
newname = strcpy(newnamebuf, cname);
if (++ncnames > 5)
{
errmsg("Possible CNAME loop");
return(FALSE);
}
result = FALSE;
h_errno = TRY_AGAIN;
continue;
}
}
else
{
hp = gethostbyaddr((char *)&inaddr, INADDRSZ, AF_INET);
if (hp != NULL)
{
print_host("Name", hp);
result = TRUE;
}
}
/* only retry if so requested */
if (!waitmode)
break;
}
/* use actual name if available */
if (realname != NULL)
name = realname;
/* explain the reason of a failure */
if (result == FALSE)
ns_error(name, querytype, queryclass, server);
return(result);
}
/*
** MYHOSTNAME -- Determine our own fully qualified host name
** ---------------------------------------------------------
**
** Returns:
** Pointer to own host name.
** Aborts if host name could not be determined.
*/
char *
myhostname()
{
struct hostent *hp;
static char mynamebuf[MAXDNAME+1];
static char *myname = NULL;
if (myname == NULL)
{
if (gethostname(mynamebuf, MAXDNAME) < 0)
{
perror("gethostname");
exit(EX_OSERR);
}
mynamebuf[MAXDNAME] = '\0';
hp = gethostbyname(mynamebuf);
if (hp == NULL)
{
ns_error(mynamebuf, T_A, C_IN, server);
errmsg("Error in looking up own name");
exit(EX_NOHOST);
}
/* cache the result */
myname = strcpy(mynamebuf, hp->h_name);
}
return(myname);
}
/*
** SET_SERVER -- Override default nameserver with explicit server
** --------------------------------------------------------------
**
** Returns:
** None.
** Aborts the program if an unknown host was given.
**
** Side effects:
** The global variable ``server'' is set to indicate
** that an explicit server is being used.
**
** The default nameserver addresses in the resolver database
** which are initialized by res_init() from /etc/resolv.conf
** are replaced with the (possibly multiple) addresses of an
** explicitly named server host. If a dotted quad is given,
** only that single address will be used.
**
** The answers from such server must be interpreted with some
** care if we don't know beforehand whether it can be trusted.
*/
void
set_server(name)
input char *name; /* name of server to be queried */
{
register int i;
struct hostent *hp;
struct in_addr inaddr;
ipaddr_t addr; /* explicit address of server */
/* check for nonsense input name */
if (strlength(name) > MAXDNAME)
{
errmsg("Server name %s too long", name);
exit(EX_USAGE);
}
/*
* Overrule the default nameserver addresses.
*/
addr = inet_addr(name);
inaddr.s_addr = addr;
if (addr == NOT_DOTTED_QUAD)
{
/* lookup all of its addresses; this must not fail */
hp = gethostbyname(name);
if (hp == NULL)
{
ns_error(name, T_A, C_IN, server);
errmsg("Error in looking up server name");
exit(EX_NOHOST);
}
for (i = 0; i < MAXNS && hp->h_addr_list[i]; i++)
{
nslist(i).sin_family = AF_INET;
nslist(i).sin_port = htons(NAMESERVER_PORT);
nslist(i).sin_addr = incopy(hp->h_addr_list[i]);
}
_res.nscount = i;
}
else
{
/* lookup the name, but use only the given address */
hp = gethostbyaddr((char *)&inaddr, INADDRSZ, AF_INET);
nslist(0).sin_family = AF_INET;
nslist(0).sin_port = htons(NAMESERVER_PORT);
nslist(0).sin_addr = inaddr;
_res.nscount = 1;
}
/*
* Indicate the use of an explicit server.
*/
if (hp != NULL)
{
server = strcpy(serverbuf, hp->h_name);
if (verbose)
print_host("Server", hp);
}
else
{
server = strcpy(serverbuf, inet_ntoa(inaddr));
if (verbose)
printf("Server: %s\n\n", server);
}
}
/*
** SET_LOGFILE -- Initialize optional log file
** -------------------------------------------
**
** Returns:
** None.
** Aborts the program if the file could not be created.
**
** Side effects:
** The global variable ``logfile'' is set to indicate
** that resource record output is to be written to it.
**
** Swap ordinary stdout and log file output if so requested.
*/
void
set_logfile(filename)
input char *filename; /* name of log file */
{
if (logexchange)
{
logfile = fdopen(dup(STDOUT), "w");
if (logfile == NULL)
{
perror("fdopen");
exit(EX_OSERR);
}
if (freopen(filename, "w", stdout) == NULL)
{
perror(filename);
exit(EX_CANTCREAT);
}
}
else
{
logfile = fopen(filename, "w");
if (logfile == NULL)
{
perror(filename);
exit(EX_CANTCREAT);
}
}
}
/*
** FATAL -- Abort program when illegal option encountered
** ------------------------------------------------------
**
** Returns:
** Aborts after issuing error message.
*/
void /*VARARGS1*/
fatal(fmt, a, b, c, d)
input char *fmt; /* format of message */
input char *a, *b, *c, *d; /* optional arguments */
{
(void) fprintf(stderr, fmt, a, b, c, d);
(void) fprintf(stderr, "\n");
exit(EX_USAGE);
}
/*
** ERRMSG -- Issue error message to error output
** ---------------------------------------------
**
** Returns:
** None.
**
** Side effects:
** Increments the global error count.
*/
void /*VARARGS1*/
errmsg(fmt, a, b, c, d)
input char *fmt; /* format of message */
input char *a, *b, *c, *d; /* optional arguments */
{
(void) fprintf(stderr, fmt, a, b, c, d);
(void) fprintf(stderr, "\n");
/* flag an error */
errorcount++;
}
/*
** GET_HOSTINFO -- Principal routine to query about given name
** -----------------------------------------------------------
**
** Returns:
** TRUE if requested info was obtained successfully.
** FALSE otherwise.
**
** This is the equivalent of the resolver module res_search().
**
** In this program RES_DEFNAMES is always on, and RES_DNSRCH
** is off by default. This means that single names without dot
** are always, and only, tried within the own default domain,
** and compound names are assumed to be already fully qualified.
**
** The default BIND behavior can be simulated by turning on
** RES_DNSRCH with -R. The given name, whether or not compound,
** is then first tried within the possible search domains.
**
** Note. In the latter case, the search terminates in case the
** specified name exists but does not have the desired type.
** The BIND behavior is to continue the search. This can be
** simulated with the undocumented option -B.
*/
bool
get_hostinfo(name, qualified)
input char *name; /* name to query about */
input bool qualified; /* assume fully qualified if set */
{
register char **domain;
register char *cp;
int dot; /* number of dots in query name */
bool result; /* result status of action taken */
char oldnamebuf[2*MAXDNAME+2];
char *oldname; /* saved actual name when NO_DATA */
int nodata = 0; /* NO_DATA status during DNSRCH */
int nquery = 0; /* number of extra search queries */
/*
* Single dot means root zone.
*/
if (sameword(name, "."))
qualified = TRUE;
/*
* Names known to be fully qualified are just tried ``as is''.
*/
if (qualified)
{
result = get_domaininfo(name, (char *)NULL);
return(result);
}
/*
* Count number of dots. Move to the end of the name.
*/
for (dot = 0, cp = name; *cp != '\0'; cp++)
if (*cp == '.')
dot++;
/*
* Check for aliases of single name.
* Note that the alias is supposed to be fully qualified.
*/
if (dot == 0 && (cp = hostalias(name)) != NULL)
{
if (verbose)
printf("Aliased to \"%s\"\n", cp);
result = get_domaininfo(cp, (char *)NULL);
return(result);
}
/*
* Trailing dot means absolute (fully qualified) address.
*/
if (dot != 0 && cp[-1] == '.')
{
cp[-1] = '\0';
result = get_domaininfo(name, (char *)NULL);
cp[-1] = '.';
return(result);
}
/*
* Append own default domain and other search domains if appropriate.
*/
if ((dot == 0 && bitset(RES_DEFNAMES, _res.options)) ||
(dot != 0 && bitset(RES_DNSRCH, _res.options)))
{
for (domain = _res.dnsrch; *domain; domain++)
{
result = get_domaininfo(name, *domain);
if (result)
return(result);
/* keep count of extra search queries */
nquery++;
/* in case nameserver not present */
if (errno == ECONNREFUSED)
return(FALSE);
/* if no further search desired (single name) */
if (!bitset(RES_DNSRCH, _res.options))
break;
/* if name exists but has not requested type */
if (h_errno == NO_DATA || h_errno == NO_RREC)
{
if (bindcompat)
{
/* remember status and search up */
oldname = strcpy(oldnamebuf, realname);
nodata = h_errno;
continue;
}
return(FALSE);
}
/* retry only if name does not exist at all */
if (h_errno != HOST_NOT_FOUND && h_errno != NO_HOST)
break;
}
}
/*
* Single name lookup failed.
*/
if (dot == 0)
{
/* unclear what actual name should be */
if (nquery != 1)
realname = NULL;
/* restore nodata status from search */
if (bindcompat && nodata)
{
realname = strcpy(realnamebuf, oldname);
h_errno = nodata;
}
/* set status in case we never queried */
if (!bitset(RES_DEFNAMES, _res.options))
h_errno = HOST_NOT_FOUND;
return(FALSE);
}
/*
* Rest means fully qualified.
*/
result = get_domaininfo(name, (char *)NULL);
/* restore nodata status from search */
if (!result && bindcompat && nodata)
{
realname = strcpy(realnamebuf, oldname);
h_errno = nodata;
}
return(result);
}
/*
** GET_DOMAININFO -- Fetch and print desired info about name in domain
** -------------------------------------------------------------------
**
** Returns:
** TRUE if requested info was obtained successfully.
** FALSE otherwise.
**
** Side effects:
** Sets global variable ``realname'' to actual name queried.
**
** This is the equivalent of the resolver module res_querydomain().
**
** Things get a little complicated in case RES_DNSRCH is on.
** If we get an answer but the data is corrupted, an error will be
** returned and NO_RECOVERY will be set. This will terminate the
** extra search loop, but a compound name will still be tried as-is.
** The same holds if the query times out or we have a server failure,
** in which case an error will be returned and TRY_AGAIN will be set.
** For now we take this for granted. Normally RES_DNSRCH is disabled.
** In this default case we do only one query and we have no problem.
*/
bool
get_domaininfo(name, domain)
input char *name; /* name to query about */
input char *domain; /* domain to which name is relative */
{
char namebuf[2*MAXDNAME+2]; /* buffer to store full domain name */
querybuf answer;
register int n;
bool result; /* result status of action taken */
/*
* Show what we are about to query.
*/
if (verbose)
{
if (domain == NULL || domain[0] == '\0')
printf("Trying %s", name);
else
printf("Trying %s within %s", name, domain);
if (server && (verbose > 1))
printf(" at server %s", server);
printf(" ...\n");
}
/*
* Construct the actual domain name.
* A null domain means the given name is already fully qualified.
* If the composite name is too long, res_mkquery() will fail.
*/
if (domain == NULL || domain[0] == '\0')
(void) sprintf(namebuf, "%.*s", MAXDNAME, name);
else
(void) sprintf(namebuf, "%.*s.%.*s",
MAXDNAME, name, MAXDNAME, domain);
name = namebuf;
/*
* Fetch the desired info.
*/
n = get_info(&answer, name, querytype, queryclass);
result = (n < 0) ? FALSE : TRUE;
/*
* Print the relevant data.
* If we got a positive answer, the data may still be corrupted.
*/
if (result)
result = print_info(&answer, n, name, querytype, FALSE);
/*
* Remember the actual name that was queried.
* Must be at the end to avoid clobbering during recursive calls.
*/
realname = strcpy(realnamebuf, name);
return(result);
}
/*
** GET_INFO -- Basic routine to issue a nameserver query
** -----------------------------------------------------
**
** Returns:
** Length of nameserver answer buffer, if obtained.
** -1 if an error occurred (h_errno is set appropriately).
**
** This is the equivalent of the resolver module res_query().
*/
int
get_info(answerbuf, name, type, class)
output querybuf *answerbuf; /* location of buffer to store answer */
input char *name; /* full name to query about */
input int type; /* specific resource record type */
input int class; /* specific resource record class */
{
querybuf query;
HEADER *bp;
int ancount;
register int n;
/*
* Construct query, and send it to the nameserver.
* res_send() will fail if no nameserver responded. In the BIND version the
* possible values for errno are ECONNREFUSED and ETIMEDOUT. If we did get
* an answer, errno should be reset, since res_send() may have left an errno
* in case it has used datagrams. Our private version of res_send() will leave
* also other error statuses, and will clear errno if an answer was obtained.
*/
errno = 0; /* reset before querying nameserver */
n = res_mkquery(QUERY, name, class, type, (qbuf_t *)NULL, 0,
(rrec_t *)NULL, (qbuf_t *)&query, sizeof(querybuf));
if (n < 0)
{
if (debug)
printf("%sres_mkquery failed\n", dbprefix);
h_errno = NO_RECOVERY;
return(-1);
}
n = res_send((qbuf_t *)&query, n, (qbuf_t *)answerbuf, sizeof(querybuf));
if (n < 0)
{
if (debug)
printf("%sres_send failed\n", dbprefix);
h_errno = TRY_AGAIN;
return(-1);
}
errno = 0; /* reset after we got an answer */
if (n < HFIXEDSZ)
{
pr_error("answer length %s too short after %s query for %s",
itoa(n), pr_type(type), name);
h_errno = NO_RECOVERY;
return(-1);
}
/*
* Analyze the status of the answer from the nameserver.
*/
if (debug || verbose)
print_status(answerbuf);
bp = (HEADER *)answerbuf;
ancount = ntohs(bp->ancount);
if (bp->rcode != NOERROR || ancount == 0)
{
switch (bp->rcode)
{
case NXDOMAIN:
/* distinguish between authoritative or not */
h_errno = bp->aa ? HOST_NOT_FOUND : NO_HOST;
break;
case NOERROR:
/* distinguish between authoritative or not */
h_errno = bp->aa ? NO_DATA : NO_RREC;
break;
case SERVFAIL:
h_errno = SERVER_FAILURE; /* instead of TRY_AGAIN */
break;
case REFUSED:
h_errno = QUERY_REFUSED; /* instead of NO_RECOVERY */
break;
default:
h_errno = NO_RECOVERY; /* FORMERR NOTIMP NOCHANGE */
break;
}
return(-1);
}
h_errno = 0;
return(n);
}
/*
** PRINT_INFO -- Check resource records in answer and print relevant data
** ----------------------------------------------------------------------
**
** Returns:
** TRUE if answer buffer was processed successfully.
** FALSE otherwise.
**
** Side effects:
** Will recurse on MAILB records if appropriate.
** See also side effects of the print_rrec() routine.
*/
bool
print_info(answerbuf, answerlen, name, type, listing)
input querybuf *answerbuf; /* location of answer buffer */
input int answerlen; /* length of answer buffer */
input char *name; /* full name we are querying about */
input int type; /* record type we are querying about */
input bool listing; /* set if this is a zone listing */
{
HEADER *bp;
int qdcount, ancount, nscount, arcount;
u_char *msg, *eom;
register u_char *cp;
bp = (HEADER *)answerbuf;
qdcount = ntohs(bp->qdcount);
ancount = ntohs(bp->ancount);
nscount = ntohs(bp->nscount);
arcount = ntohs(bp->arcount);
msg = (u_char *)answerbuf;
eom = (u_char *)answerbuf + answerlen;
cp = (u_char *)answerbuf + HFIXEDSZ;
/*
* Skip the query section in the response (present only in normal queries).
*/
if (qdcount)
{
while (qdcount > 0 && cp < eom)
{
/* cp += dn_skipname(cp, eom) + QFIXEDSZ; */
cp = skip_qrec(name, cp, msg, eom);
if (cp == NULL)
return(FALSE);
qdcount--;
}
if (qdcount)
{
pr_error("invalid qdcount after %s query for %s",
pr_type(type), name);
h_errno = NO_RECOVERY;
return(FALSE);
}
}
/*
* Process the actual answer section in the response.
* During zone transfers, this is the only section available.
*/
if (ancount)
{
if (!listing && verbose && !bp->aa)
printf("The following answer is not authoritative:\n");
while (ancount > 0 && cp < eom)
{
cp = print_rrec(name, cp, msg, eom, listing);
if (cp == NULL)
return(FALSE);
ancount--;
/*
* When we ask for address and there is a CNAME, it returns
* both the CNAME and the address. Since we trace down the
* CNAME chain ourselves, we don't really want to print the
* address at this point.
*/
if (!listmode && !verbose && cname)
return(TRUE);
/*
* Recursively expand MR or MG records into MB records.
*/
if (!listmode && mailmode && mname)
{
char newnamebuf[MAXDNAME+1];
char *newname;
newname = strcpy(newnamebuf, mname);
mname = NULL;
(void) get_recursive(newname);
}
}
if (ancount)
{
pr_error("invalid ancount after %s query for %s",
pr_type(type), name);
h_errno = NO_RECOVERY;
return(FALSE);
}
}
/*
* The nameserver and additional info section are normally not processed.
* Both sections shouldn't exist in zone transfers.
*/
if (!verbose || exclusive)
return(TRUE);
if (nscount)
{
printf("Authoritative nameservers:\n");
while (nscount > 0 && cp < eom)
{
cp = print_rrec(name, cp, msg, eom, FALSE);
if (cp == NULL)
return(FALSE);
nscount--;
}
if (nscount)
{
pr_error("invalid nscount after %s query for %s",
pr_type(type), name);
h_errno = NO_RECOVERY;
return(FALSE);
}
}
if (arcount)
{
printf("Additional information:\n");
while (arcount > 0 && cp < eom)
{
cp = print_rrec(name, cp, msg, eom, FALSE);
if (cp == NULL)
return(FALSE);
arcount--;
}
if (arcount)
{
pr_error("invalid arcount after %s query for %s",
pr_type(type), name);
h_errno = NO_RECOVERY;
return(FALSE);
}
}
return(TRUE);
}
/*
** PRINT_DATA -- Output resource record data if this record is wanted
** ------------------------------------------------------------------
**
** Returns:
** None.
**
** Inputs:
** The global variable ``doprint'' is set by print_rrec()
** if we need to print the data.
*/
static bool doprint; /* indicates whether or not to print */
void /*VARARGS1*/
print_data(fmt, a, b, c, d)
input char *fmt; /* format of message */
input char *a, *b, *c, *d; /* optional arguments */
{
/* if (doprint) */
{
if (!suppress)
printf(fmt, a, b, c, d);
if (logfile != NULL)
(void) fprintf(logfile, fmt, a, b, c, d);
}
}
#define doprintf(x)\
{\
if (doprint)\
{\
print_data x ;\
}\
}
/*
** PRINT_RREC -- Decode single resource record and output relevant data
** --------------------------------------------------------------------
**
** Returns:
** Pointer to position in answer buffer after current record.
** NULL if there was a format error in the current record.
**
** Outputs:
** The global variable ``doprint'' is set appropriately
** for use by print_data().
**
** Side effects:
** Updates resource record statistics in record_stats[].
** Sets ``soaname'' if this is an SOA record.
** Sets ``subname'' if this is an NS record.
** Sets ``adrname'' if this is an A record.
** Sets ``address'' if this is an A record.
** Sets ``cname'' if this is a valid CNAME record.
** Sets ``mname'' if this is a valid MAILB record.
** These variables must have been cleared before calling
** print_info() and may be checked afterwards.
*/
/* print domain names after certain conversions */
#define pr_name(x) pr_domain(x, listing)
/* check the LHS record name of these records for invalid characters */
#define test_valid(t) ((t == T_A && !reverse) || t == T_MX || t == T_AAAA)
/* check the RHS domain name of these records for canonical host names */
#define test_canon(t) (t == T_NS || t == T_MX)
u_char *
print_rrec(name, cp, msg, eom, listing)
input char *name; /* full name we are querying about */
register u_char *cp; /* current position in answer buf */
input u_char *msg, *eom; /* begin and end of answer buf */
input bool listing; /* set if this is a zone listing */
{
char rname[MAXDNAME+1]; /* record name in LHS */
char dname[MAXDNAME+1]; /* domain name in RHS */
int type, class, ttl, dlen; /* fixed values in every record */
u_char *eor; /* predicted position of next record */
bool classmatch; /* set if we want to see this class */
char *host = listhost; /* contacted host for zone listings */
register int n, c;
struct in_addr inaddr;
struct protoent *protocol;
struct servent *service;
/*
* Pickup the standard values present in each resource record.
*/
n = expand_name(name, T_NONE, cp, msg, eom, rname);
if (n < 0)
return(NULL);
cp += n;
n = 3*INT16SZ + INT32SZ;
if (check_size(rname, T_NONE, cp, msg, eom, n) < 0)
return(NULL);
type = _getshort(cp);
cp += INT16SZ;
class = _getshort(cp);
cp += INT16SZ;
ttl = _getlong(cp);
cp += INT32SZ;
dlen = _getshort(cp);
cp += INT16SZ;
eor = cp + dlen;
/*
* Decide whether or not to print this resource record.
*/
if (listing)
{
classmatch = want_class(class, queryclass);
doprint = classmatch && want_type(type, querytype);
}
else
{
classmatch = want_class(class, C_ANY);
doprint = classmatch && want_type(type, T_ANY);
}
#ifdef obsolete
if (doprint && exclusive && !samedomain(rname, name, TRUE))
doprint = FALSE;
#endif
if (doprint && exclusive && !indomain(rname, name, TRUE))
doprint = FALSE;
if (doprint && exclusive && fakename(rname))
doprint = FALSE;
if (doprint && wildcards && !in_string(rname, '*'))
doprint = FALSE;
#ifdef justfun
if (namelen && (strlength(rname) < namelen))
doprint = FALSE;
#endif
/*
* Print name and common values, if appropriate.
*/
doprintf(("%-20s", pr_name(rname)))
if (verbose || ttlprint)
doprintf(("\t%s", itoa(ttl)))
if (verbose || classprint || (class != queryclass))
doprintf(("\t%s", pr_class(class)))
doprintf(("\t%s", pr_type(type)))
/*
* Update resource record statistics for zone listing.
*/
if (listing && classmatch)
{
if (type >= T_FIRST && type <= T_LAST)
record_stats[type]++;
}
/*
* Save the domain name of an SOA or NS or A record for zone listing.
*/
if (listing && classmatch)
{
if (type == T_A)
adrname = strcpy(adrnamebuf, rname);
else if (type == T_NS)
subname = strcpy(subnamebuf, rname);
else if (type == T_SOA)
soaname = strcpy(soanamebuf, rname);
}
/*
* Print type specific data, if appropriate.
*/
switch (type)
{
case T_A:
if (class == C_IN || class == C_HS)
{
if (dlen == INADDRSZ)
{
bcopy((char *)cp, (char *)&inaddr, INADDRSZ);
address = inaddr.s_addr;
doprintf(("\t%s", inet_ntoa(inaddr)))
cp += INADDRSZ;
break;
}
if (dlen == INADDRSZ + 1 + INT16SZ)
{
bcopy((char *)cp, (char *)&inaddr, INADDRSZ);
address = inaddr.s_addr;
doprintf(("\t%s", inet_ntoa(inaddr)))
cp += INADDRSZ;
n = *cp++;
doprintf((" ; proto = %s", itoa(n)))
n = _getshort(cp);
doprintf((", port = %s", itoa(n)))
cp += INT16SZ;
break;
}
address = 0;
break;
}
address = 0;
cp += dlen;
break;
case T_MX:
if (check_size(rname, type, cp, msg, eor, INT16SZ) < 0)
break;
n = _getshort(cp);
doprintf(("\t%s", itoa(n)))
cp += INT16SZ;
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf((" %s", pr_name(dname)))
cp += n;
break;
case T_NS:
case T_PTR:
case T_CNAME:
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf(("\t%s", pr_name(dname)))
cp += n;
break;
case T_HINFO:
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("\t\"%s\"", stoa(cp, n)))
cp += n;
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("\t\"%s\"", stoa(cp, n)))
cp += n;
break;
case T_SOA:
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf(("\t%s", pr_name(dname)))
cp += n;
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf((" %s", pr_name(dname)))
cp += n;
n = 5*INT32SZ;
if (check_size(rname, type, cp, msg, eor, n) < 0)
break;
doprintf((" ("))
n = _getlong(cp);
doprintf(("\n\t\t\t%s", utoa(n)))
doprintf(("\t;serial (version)"))
cp += INT32SZ;
n = _getlong(cp);
doprintf(("\n\t\t\t%s", itoa(n)))
doprintf(("\t;refresh period (%s)", pr_time(n, FALSE)))
cp += INT32SZ;
n = _getlong(cp);
doprintf(("\n\t\t\t%s", itoa(n)))
doprintf(("\t;retry interval (%s)", pr_time(n, FALSE)))
cp += INT32SZ;
n = _getlong(cp);
doprintf(("\n\t\t\t%s", itoa(n)))
doprintf(("\t;expire time (%s)", pr_time(n, FALSE)))
cp += INT32SZ;
n = _getlong(cp);
doprintf(("\n\t\t\t%s", itoa(n)))
doprintf(("\t;default ttl (%s)", pr_time(n, FALSE)))
cp += INT32SZ;
doprintf(("\n\t\t\t)"))
break;
case T_WKS:
if (check_size(rname, type, cp, msg, eor, INADDRSZ) < 0)
break;
bcopy((char *)cp, (char *)&inaddr, INADDRSZ);
doprintf(("\t%s", inet_ntoa(inaddr)))
cp += INADDRSZ;
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
protocol = getprotobynumber(n);
if (protocol != NULL)
doprintf((" %s", protocol->p_name))
else
doprintf((" %s", itoa(n)))
doprintf((" ("))
n = 0;
while (cp < eor)
{
c = *cp++;
do
{
if (c & 0200)
{
int port;
port = htons(n);
if (protocol != NULL)
service = getservbyport(port, protocol->p_name);
else
service = NULL;
if (service != NULL)
doprintf((" %s", service->s_name))
else
doprintf((" %s", itoa(n)))
}
c <<= 1;
} while (++n & 07);
}
doprintf((" )"))
break;
#ifdef obsolete
case T_TXT:
if (dlen > 0)
{
doprintf(("\t\"%s\"", stoa(cp, dlen)))
cp += dlen;
}
break;
#endif
case T_TXT:
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("\t\"%s", stoa(cp, n)))
cp += n;
while (cp < eor)
{
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("%s", stoa(cp, n)))
cp += n;
}
doprintf(("\""))
break;
case T_MINFO:
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf(("\t%s", pr_name(dname)))
cp += n;
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf((" %s", pr_name(dname)))
cp += n;
break;
case T_MB:
case T_MG:
case T_MR:
case T_MD:
case T_MF:
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf(("\t%s", pr_name(dname)))
cp += n;
break;
case T_UID:
case T_GID:
if (dlen == INT32SZ)
{
n = _getlong(cp);
doprintf(("\t%s", itoa(n)))
cp += INT32SZ;
}
break;
case T_UINFO:
doprintf(("\t\"%s\"", stoa(cp, dlen)))
cp += dlen;
break;
case T_RP:
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf(("\t%s", pr_name(dname)))
cp += n;
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf((" %s", pr_name(dname)))
cp += n;
break;
case T_RT:
if (check_size(rname, type, cp, msg, eor, INT16SZ) < 0)
break;
n = _getshort(cp);
doprintf(("\t%s", itoa(n)))
cp += INT16SZ;
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf((" %s", pr_name(dname)))
cp += n;
break;
case T_AFSDB:
if (check_size(rname, type, cp, msg, eor, INT16SZ) < 0)
break;
n = _getshort(cp);
doprintf(("\t%s", itoa(n)))
cp += INT16SZ;
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf((" %s", pr_name(dname)))
cp += n;
break;
case T_X25:
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("\t%s", stoa(cp, n)))
cp += n;
break;
case T_ISDN:
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("\t%s", stoa(cp, n)))
cp += n;
if (cp < eor)
{
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf((" %s", stoa(cp, n)))
cp += n;
}
break;
case T_NSAP:
doprintf(("\t0x%s", nsap_ntoa(cp, dlen)))
cp += dlen;
break;
case T_NSAPPTR:
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf(("\t%s", pr_name(dname)))
cp += n;
break;
case T_PX:
if (check_size(rname, type, cp, msg, eor, INT16SZ) < 0)
break;
n = _getshort(cp);
doprintf(("\t%s", itoa(n)))
cp += INT16SZ;
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf((" %s", pr_name(dname)))
cp += n;
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
break;
doprintf((" %s", pr_name(dname)))
cp += n;
break;
case T_GPOS:
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("\t%s", stoa(cp, n)))
cp += n;
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("\t%s", stoa(cp, n)))
cp += n;
if (check_size(rname, type, cp, msg, eor, 1) < 0)
break;
n = *cp++;
doprintf(("\t%s", stoa(cp, n)))
cp += n;
break;
case T_LOC:
if ((n = *cp) != T_LOC_VERSION)
{
pr_error("invalid version %s in %s record for %s",
itoa(n), pr_type(type), rname);
cp += dlen;
break;
}
n = INT32SZ + 3*INT32SZ;
if (check_size(rname, type, cp, msg, eor, n) < 0)
break;
c = _getlong(cp);
cp += INT32SZ;
n = _getlong(cp);
doprintf(("\t%s ", pr_spherical(n, "N", "S")))
cp += INT32SZ;
n = _getlong(cp);
doprintf((" %s ", pr_spherical(n, "E", "W")))
cp += INT32SZ;
n = _getlong(cp);
doprintf((" %sm ", pr_vertical(n, "", "-")))
cp += INT32SZ;
doprintf((" %sm", pr_precision((c >> 16) & 0xff)))
doprintf((" %sm", pr_precision((c >> 8) & 0xff)))
doprintf((" %sm", pr_precision((c >> 0) & 0xff)))
break;
case T_UNSPEC:
case T_NULL:
cp += dlen;
break;
case T_SIG:
case T_KEY:
case T_AAAA:
doprintf(("\t(not yet implemented)"))
cp += dlen;
break;
default:
doprintf(("\t???"))
cp += dlen;
break;
}
/*
* Terminate resource record printout.
*/
doprintf(("\n"))
/*
* Check whether we have reached the exact end of this resource record.
* If not, we cannot be sure that the record has been decoded correctly,
* and therefore the subsequent tests will be skipped.
*/
if (cp != eor)
{
pr_error("size error in %s record for %s, off by %s",
pr_type(type), rname, itoa(cp - eor));
/* we believe value of dlen; should perhaps return(NULL) */
return(eor);
}
/*
* Save the CNAME alias for cname chain tracing.
* Save the MR or MG alias for MB chain tracing.
* These features can be enabled only in normal mode.
*/
if (!listmode && classmatch)
{
if (type == T_CNAME)
cname = strcpy(cnamebuf, dname);
else if (type == T_MR || type == T_MG)
mname = strcpy(mnamebuf, dname);
}
/*
* Suppress the subsequent checks in quiet mode.
* This can safely be done as there are no side effects.
* It may speedup things, and nothing would be printed anyway.
*/
if (quiet)
return(cp);
/*
* In zone listings, resource records with the same name/type/class
* must have the same ttl value. Maintain and check list of record info.
* This is done on a per-zone basis.
*/
if (listing && !check_ttl(rname, type, class, ttl))
{
pr_warning("%s %s records have different ttl within %s from %s",
rname, pr_type(type), name, host);
}
/*
* Check validity of 'host' related domain names in certain resource records.
* These include LHS record names and RHS domain names of selected records.
* Currently underscores are not reported during deep recursive listings.
*/
if (test_valid(type) && !valid_name(rname, TRUE, FALSE, recurskip))
{
pr_warning("%s %s record has illegal name",
rname, pr_type(type));
}
if (test_canon(type) && !valid_name(dname, FALSE, FALSE, recurskip))
{
pr_warning("%s %s host %s has illegal name",
rname, pr_type(type), dname);
}
/*
* The RHS of various resource records should refer to a canonical host name,
* i.e. it should exist and have an A record and not be a CNAME.
* Currently this test is suppressed during deep recursive zone listings.
*/
if (!recurskip && test_canon(type) && (n = check_canon(dname)) != 0)
{
/* only report definitive target host failures */
if (n == HOST_NOT_FOUND)
pr_warning("%s %s host %s does not exist",
rname, pr_type(type), dname);
else if (n == NO_DATA)
pr_warning("%s %s host %s has no A record",
rname, pr_type(type), dname);
else if (n == HOST_NOT_CANON)
pr_warning("%s %s host %s is not canonical",
rname, pr_type(type), dname);
/* authoritative failure to find nameserver target host */
if (type == T_NS && (n == NO_DATA || n == HOST_NOT_FOUND))
{
if (server == NULL)
errmsg("%s has lame delegation to %s",
rname, dname);
}
}
/*
* On request, reverse map the address of an A record, and verify that
* it is registered and maps back to the name of the A record.
* Currently this option has effect here only during zone listings.
*/
if (addrmode && (type == T_A && !reverse) && !fakeaddr(address))
{
host = mapreverse(rname, inaddr);
if (host == NULL)
pr_warning("%s address %s is not registered",
rname, inet_ntoa(inaddr));
else if (host != rname)
pr_warning("%s address %s maps to %s",
rname, inet_ntoa(inaddr), host);
}
/*
* This record was processed successfully.
*/
return(cp);
}
/*
** SKIP_QREC -- Skip the query record in the nameserver answer buffer
** ------------------------------------------------------------------
**
** Returns:
** Pointer to position in answer buffer after current record.
** NULL if there was a format error in the current record.
*/
u_char *
skip_qrec(name, cp, msg, eom)
input char *name; /* full name we are querying about */
register u_char *cp; /* current position in answer buf */
input u_char *msg, *eom; /* begin and end of answer buf */
{
char rname[MAXDNAME+1]; /* record name in LHS */
int type, class; /* fixed values in query record */
register int n;
n = expand_name(name, T_NONE, cp, msg, eom, rname);
if (n < 0)
return(NULL);
cp += n;
n = 2*INT16SZ;
if (check_size(rname, T_NONE, cp, msg, eom, n) < 0)
return(NULL);
type = _getshort(cp);
cp += INT16SZ;
class = _getshort(cp);
cp += INT16SZ;
#ifdef lint
if (verbose)
printf("%-20s\t%s\t%s\n",
rname, pr_class(class), pr_type(type));
#endif
return(cp);
}
/*
** GET_RECURSIVE -- Wrapper for get_hostinfo() during recursion
** ------------------------------------------------------------
**
** Returns:
** TRUE if requested info was obtained successfully.
** FALSE otherwise.
*/
bool
get_recursive(name)
input char *name; /* name to query about */
{
static int level = 0; /* recursion level */
bool result; /* result status of action taken */
int save_errno;
int save_herrno;
if (level > 5)
{
errmsg("Recursion too deep");
return(FALSE);
}
save_errno = errno;
save_herrno = h_errno;
level++;
result = get_hostinfo(name, TRUE);
level--;
errno = save_errno;
h_errno = save_herrno;
return(result);
}
/*
* Nameserver information.
* Stores names and addresses of all servers that are to be queried
* for a zone transfer of the desired zone. Normally these are the
* authoritative primary and/or secondary nameservers for the zone.
*/
char nsname[MAXNSNAME][MAXDNAME+1]; /* nameserver host name */
struct in_addr ipaddr[MAXNSNAME][MAXIPADDR]; /* nameserver addresses */
int naddrs[MAXNSNAME]; /* count of addresses */
int nservers = 0; /* count of nameservers */
#ifdef notyet
typedef struct srvr_data {
char nsname[MAXDNAME+1]; /* nameserver host name */
struct in_addr ipaddr[MAXIPADDR]; /* nameserver addresses */
int naddrs; /* count of addresses */
} srvr_data_t;
srvr_data_t nsinfo[MAXNSNAME]; /* nameserver info */
#endif
bool authserver; /* server is supposed to be authoritative */
bool lameserver; /* server could not provide SOA service */
/*
* Host information.
* Stores names and (single) addresses encountered during the zone listing
* of all A records that belong to the zone. Non-authoritative glue records
* that do not belong to the zone are not stored. Glue records that belong
* to a delegated zone will be filtered out later during the host count scan.
* The host names are allocated dynamically.
#ifdef notyet
* The host data should have been allocated dynamically to avoid static
* limits, but this is less important since it is not saved across calls.
* In case the static limit is reached, increase MAXHOSTS and recompile.
#endif
*/
char *hostname[MAXHOSTS]; /* host name of host in zone */
ipaddr_t hostaddr[MAXHOSTS]; /* first host address */
bool multaddr[MAXHOSTS]; /* set if this is a multiple address host */
int hostcount = 0; /* count of hosts in zone */
#ifdef notyet
typedef struct host_data {
char *hostname; /* host name of host in zone */
ipaddr_t hostaddr; /* first host address */
bool multaddr; /* set if this is a multiple address host */
} host_data_t;
host_data_t hostlist[MAXHOSTS]; /* info on hosts in zone */
#endif
/*
* Delegated zone information.
* Stores the names of the delegated zones encountered during the zone
* listing. The names and the list itself are allocated dynamically.
*/
char **zonename = NULL; /* names of delegated zones within zone */
int zonecount = 0; /* count of delegated zones within zone */
/*
* Address information.
* Stores the (single) addresses of hosts found in all zones traversed.
* Used to search for duplicate hosts (same address but different name).
* The list of addresses is allocated dynamically, and remains allocated.
* This has now been implemented as a hashed list, using the low-order
* address bits as the hash key.
*/
#ifdef obsolete
ipaddr_t *addrlist = NULL; /* global list of addresses */
int addrcount = 0; /* count of global addresses */
#endif
/*
* SOA record information.
*/
soa_data_t soa; /* buffer to store soa data */
/*
* Nameserver preference.
* As per BIND 4.9.* resource records may be returned after round-robin
* reshuffling each time they are retrieved. For NS records, this may
* lead to an unfavorable order for doing zone transfers.
* We apply some heuristic to sort the NS records according to their
* preference with respect to a given list of preferred server domains.
*/
int nsrank[MAXNSNAME]; /* nameserver ranking after sorting */
int nspref[MAXNSNAME]; /* nameserver preference value */
/*
** LIST_ZONE -- Basic routine to do complete zone listing and checking
** -------------------------------------------------------------------
**
** Returns:
** TRUE if the requested info was processed successfully.
** FALSE otherwise.
*/
int total_calls = 0; /* number of calls for zone processing */
int total_check = 0; /* number of zones successfully processed */
int total_tries = 0; /* number of zone transfer attempts */
int total_zones = 0; /* number of successful zone transfers */
int total_hosts = 0; /* number of hosts in all traversed zones */
int total_dupls = 0; /* number of duplicates in all zones */
#ifdef justfun
char longname[MAXDNAME+1]; /* longest host name found */
int longsize = 0; /* size of longest host name */
#endif
bool
list_zone(name)
input char *name; /* name of zone to process */
{
register int n;
register int i;
int nzones; /* count of delegated zones */
int nhosts; /* count of real host names */
int ndupls; /* count of duplicate hosts */
int nextrs; /* count of extrazone hosts */
int ngates; /* count of gateway hosts */
total_calls += 1; /* update zone processing calls */
/*
* Normalize to not have trailing dot, unless it is the root zone.
*/
n = strlength(name);
if (n > 1 && name[n-1] == '.')
name[n-1] = '\0';
/*
* Indicate whether we are processing an in-addr.arpa reverse zone.
* In this case we will suppress accumulating host count statistics.
*/
reverse = indomain(name, ARPA_ROOT, FALSE);
/*
* Suppress various checks if working beyond the recursion skip level.
* This affects processing in print_rrec(). It may need refinement.
*/
recurskip = (recursion_level > skip_level) ? TRUE : FALSE;
/*
* Find the nameservers for the given zone.
*/
(void) find_servers(name);
if (nservers < 1)
{
errmsg("No nameservers for %s found", name);
return(FALSE);
}
/*
* Make sure we have an address for at least one nameserver.
*/
for (n = 0; n < nservers; n++)
if (naddrs[n] > 0)
break;
if (n >= nservers)
{
errmsg("No addresses of nameservers for %s found", name);
return(FALSE);
}
/*
* Without an explicit server on the command line, the servers we
* have looked up are supposed to be authoritative for the zone.
*/
authserver = server ? FALSE : TRUE;
/*
* Check SOA records at each of the nameservers if so requested.
*/
if (checkmode)
{
do_check(name);
total_check += 1; /* update zones processed */
/* all done if maximum recursion level reached */
if (!recursive || (recursion_level >= recursive))
return((errorcount == 0) ? TRUE : FALSE);
}
/*
* The zone transfer for certain zones can be skipped.
* Currently this must be indicated on the command line.
*/
if (skip_transfer(name))
{
if (verbose || statistics || checkmode || hostmode)
printf("Skipping zone transfer for %s\n", name);
return(FALSE);
}
/*
* Ask zone transfer to the nameservers, until one responds.
*/
total_tries += 1; /* update zone transfer attempts */
if (!do_transfer(name))
return(FALSE);
total_zones += 1; /* update successful zone transfers */
/*
* Print resource record statistics if so requested.
*/
if (statistics)
print_statistics(name, querytype, queryclass);
/*
* Accumulate host count statistics for this zone.
* Do this only in modes in which such output would be printed.
*/
nzones = zonecount;
nhosts = 0, ndupls = 0, nextrs = 0, ngates = 0;
i = (verbose || statistics || hostmode) ? 0 : hostcount;
for (n = i; n < hostcount; n++)
{
/* skip fake hosts using a very rudimentary test */
if (fakename(hostname[n]) || fakeaddr(hostaddr[n]))
continue;
#ifdef justfun
/* save longest host name encountered so far */
if (verbose && ((i = strlength(hostname[n])) > longsize))
{
longsize = i;
(void) strcpy(longname, hostname[n]);
}
#endif
/* skip apparent glue records */
if (gluerecord(hostname[n], name, zonename, nzones))
{
if (verbose > 1)
printf("%s is glue record\n", hostname[n]);
continue;
}
/* otherwise count as host */
nhosts++;
/*
* Mark hosts not residing directly in the zone as extrazone host.
*/
if (!samedomain(hostname[n], name, TRUE))
{
nextrs++;
if (extrmode || (verbose > 1))
printf("%s is extrazone host\n", hostname[n]);
}
/*
* Mark hosts with more than one address as gateway host.
* These are not checked for duplicate addresses.
*/
if (multaddr[n])
{
ngates++;
if (gatemode || (verbose > 1))
printf("%s is gateway host\n", hostname[n]);
}
/*
* Compare single address hosts against global list of addresses.
* Multiple address hosts are too complicated to handle this way.
*/
else if (check_dupl(hostaddr[n]))
{
struct in_addr inaddr;
inaddr.s_addr = hostaddr[n];
ndupls++;
if (duplmode || (verbose > 1))
printf("%s is duplicate host with address %s\n",
hostname[n], inet_ntoa(inaddr));
}
}
/*
* Print statistics for this zone.
*/
if (verbose || statistics || hostmode)
{
printf("Found %d host%s within %s\n",
nhosts, plural(nhosts), name);
if ((ndupls > 0) || duplmode || (verbose > 1))
printf("Found %d duplicate host%s within %s\n",
ndupls, plural(ndupls), name);
if ((nextrs > 0) || extrmode || (verbose > 1))
printf("Found %d extrazone host%s within %s\n",
nextrs, plural(nextrs), name);
if ((ngates > 0) || gatemode || (verbose > 1))
printf("Found %d gateway host%s within %s\n",
ngates, plural(ngates), name);
}
total_hosts += nhosts; /* update total number of hosts */
total_dupls += ndupls; /* update total number of duplicates */
if (!checkmode)
total_check += 1; /* update zones processed */
if (verbose || statistics)
printf("Found %d delegated zone%s within %s\n",
nzones, plural(nzones), name);
/*
* Sort the encountered delegated zones alphabetically.
* Note that this precludes further use of the zone_index() function.
*/
if ((nzones > 1) && (recursive || listzones || mxdomains))
qsort((char *)zonename, nzones, sizeof(char *), compare_name);
/*
* The names of the hosts were allocated dynamically.
*/
for (n = 0; n < hostcount; n++)
xfree(hostname[n]);
/*
* Check for mailable delegated zones within this zone.
* This is based on ordinary MX lookup, and not on the MX info
* which may be present in the zone listing, to reduce zone transfers.
*/
if (mxdomains)
{
if (recursion_level == 0)
{
if (verbose)
printf("\n");
if (!get_mxrec(name))
ns_error(name, T_MX, queryclass, server);
}
for (n = 0; n < nzones; n++)
{
if (verbose)
printf("\n");
if (!get_mxrec(zonename[n]))
ns_error(zonename[n], T_MX, queryclass, server);
}
}
/*
* Do recursion on delegated zones if requested and any were found.
* Temporarily save zonename list, and force allocation of new list.
*/
if (recursive && (recursion_level < recursive))
{
for (n = 0; n < nzones; n++)
{
char **newzone; /* local copy of list */
newzone = zonename;
zonename = NULL; /* allocate new list */
if (verbose || statistics || checkmode || hostmode)
printf("\n");
if (listzones)
{
for (i = 0; i <= recursion_level; i++)
printf("%s", (i == 0) ? "\t" : " ");
printf("%s\n", newzone[n]);
}
if (verbose)
printf("Entering zone %s\n", newzone[n]);
recursion_level++;
(void) list_zone(newzone[n]);
recursion_level--;
zonename = newzone; /* restore */
}
}
else if (listzones)
{
for (n = 0; n < nzones; n++)
{
for (i = 0; i <= recursion_level; i++)
printf("%s", (i == 0) ? "\t" : " ");
printf("%s\n", zonename[n]);
}
}
/*
* The names of the delegated zones were allocated dynamically.
* The list of delegated zone names was also allocated dynamically.
*/
for (n = 0; n < nzones; n++)
xfree(zonename[n]);
if (zonename != NULL)
xfree(zonename);
zonename = NULL;
/*
* Print final overall statistics.
*/
if (recursive && (recursion_level == 0))
{
if (verbose || statistics || checkmode || hostmode)
printf("\n");
if (verbose || statistics || hostmode)
printf("Encountered %d host%s in %d zone%s within %s\n",
total_hosts, plural(total_hosts),
total_zones, plural(total_zones),
name);
if (verbose || statistics || hostmode)
printf("Encountered %d duplicate host%s in %d zone%s within %s\n",
total_dupls, plural(total_dupls),
total_zones, plural(total_zones),
name);
if (verbose || statistics || checkmode)
printf("Transferred %d zone%s out of %d attempt%s\n",
total_zones, plural(total_zones),
total_tries, plural(total_tries));
if (verbose || statistics || checkmode)
printf("Processed %d zone%s out of %d request%s\n",
total_check, plural(total_check),
total_calls, plural(total_calls));
#ifdef justfun
if (verbose && (longsize > 0))
printf("Longest hostname %s\t%d\n",
longname, longsize);
#endif
}
/* indicate whether any errors were encountered */
return((errorcount == 0) ? TRUE : FALSE);
}
/*
** FIND_SERVERS -- Fetch names and addresses of authoritative servers
** ------------------------------------------------------------------
**
** Returns:
** TRUE if servers could be determined successfully.
** FALSE otherwise.
**
** Inputs:
** The global variable ``server'', if set, contains the
** name of the explicit server to be contacted.
** The global variable ``primary'', if set, indicates
** that we must use the primary nameserver for the zone.
** If both are set simultaneously, the explicit server
** is contacted to retrieve the desired servers.
**
** Outputs:
** The count of nameservers is stored in ``nservers''.
** Names are stored in the nsname[] database.
** Addresses are stored in the ipaddr[] database.
** Address counts are stored in the naddrs[] database.
*/
bool
find_servers(name)
input char *name; /* name of zone to find servers for */
{
struct hostent *hp;
register int n;
register int i;
/*
* Use the explicit server if given on the command line.
* Its addresses are stored in the resolver state struct.
* This server may not be authoritative for the given zone.
*/
if (server && !primary)
{
(void) strcpy(nsname[0], server);
for (i = 0; i < MAXIPADDR && i < _res.nscount; i++)
ipaddr[0][i] = nslist(i).sin_addr;
naddrs[0] = i;
nservers = 1;
return(TRUE);
}
/*
* Fetch primary nameserver info if so requested.
* Get its name from the SOA record for the zone, and do a regular
* host lookup to fetch its addresses. We are assuming here that the
* SOA record is a proper one. This is not necessarily true.
* Obviously this server should be authoritative.
*/
if (primary && !server)
{
char *primaryname;
primaryname = get_primary(name);
if (primaryname == NULL)
{
ns_error(name, T_SOA, queryclass, server);
nservers = 0;
return(FALSE);
}
hp = gethostbyname(primaryname);
if (hp == NULL)
{
ns_error(primaryname, T_A, C_IN, server);
nservers = 0;
return(FALSE);
}
(void) strcpy(nsname[0], hp->h_name);
for (i = 0; i < MAXIPADDR && hp->h_addr_list[i]; i++)
ipaddr[0][i] = incopy(hp->h_addr_list[i]);
naddrs[0] = i;
if (verbose)
printf("Found %d address%-2s for %s\n",
naddrs[0], plurale(naddrs[0]), nsname[0]);
nservers = 1;
return(TRUE);
}
/*
* Otherwise we have to find the nameservers for the zone.
* These are supposed to be authoritative, but sometimes we
* encounter lame delegations, perhaps due to misconfiguration.
* Retrieve the NS records for this zone.
*/
if (!get_servers(name))
{
ns_error(name, T_NS, queryclass, server);
nservers = 0;
return(FALSE);
}
/*
* Usually we'll get addresses for all the servers in the additional
* info section. But in case we don't, look up their addresses.
* Addresses could be missing because there is no room in the answer.
* No address is present if the name of a server is not canonical.
* If we get no addresses by extra query, and this is authoritative,
* we flag a lame delegation to that server.
*/
for (n = 0; n < nservers; n++)
{
if (naddrs[n] == 0)
{
hp = gethostbyname(nsname[n]);
if (hp != NULL)
{
for (i = 0; i < MAXIPADDR && hp->h_addr_list[i]; i++)
ipaddr[n][i] = incopy(hp->h_addr_list[i]);
naddrs[n] = i;
}
if (verbose)
printf("Found %d address%-2s for %s by extra query\n",
naddrs[n], plurale(naddrs[n]), nsname[n]);
if (hp == NULL)
{
/* server name lookup failed */
ns_error(nsname[n], T_A, C_IN, server);
/* authoritative denial: probably misconfiguration */
if (h_errno == NO_DATA || h_errno == HOST_NOT_FOUND)
{
errmsg("%s has lame delegation to %s",
name, nsname[n]);
}
}
if ((hp != NULL) && !sameword(hp->h_name, nsname[n]))
pr_warning("%s nameserver %s is not canonical (%s)",
name, nsname[n], hp->h_name);
}
else
{
if (verbose)
printf("Found %d address%-2s for %s\n",
naddrs[n], plurale(naddrs[n]), nsname[n]);
}
}
/*
* Issue warning if only one server has been discovered.
* This is not an error per se, but not much redundancy in that case.
*/
if (nservers == 1)
pr_warning("%s has only one nameserver %s",
name, nsname[0]);
return((nservers > 0) ? TRUE : FALSE);
}
/*
** GET_SERVERS -- Fetch names and addresses of authoritative servers
** -----------------------------------------------------------------
**
** Returns:
** TRUE if servers could be determined successfully.
** FALSE otherwise.
**
** Side effects:
** The count of nameservers is stored in ``nservers''.
** Names are stored in the nsname[] database.
** Addresses are stored in the ipaddr[] database.
** Address counts are stored in the naddrs[] database.
*/
bool
get_servers(name)
input char *name; /* name of zone to find servers for */
{
querybuf answer;
register int n;
bool result; /* result status of action taken */
if (verbose)
printf("Finding nameservers for %s ...\n", name);
n = get_info(&answer, name, T_NS, queryclass);
if (n < 0)
return(FALSE);
if (verbose > 1)
(void) print_info(&answer, n, name, T_NS, FALSE);
result = get_nsinfo(&answer, n, name);
return(result);
}
/*
** GET_NSINFO -- Extract nameserver data from nameserver answer buffer
** -------------------------------------------------------------------
**
** Returns:
** TRUE if servers could be determined successfully.
** FALSE otherwise.
**
** Outputs:
** The count of nameservers is stored in ``nservers''.
** Names are stored in the nsname[] database.
** Addresses are stored in the ipaddr[] database.
** Address counts are stored in the naddrs[] database.
*/
bool
get_nsinfo(answerbuf, answerlen, name)
input querybuf *answerbuf; /* location of answer buffer */
input int answerlen; /* length of answer buffer */
input char *name; /* name of zone to find servers for */
{
HEADER *bp;
int qdcount, ancount, nscount, arcount, rrcount;
u_char *msg, *eom;
register u_char *cp;
register int i;
nservers = 0; /* count of nameservers */
bp = (HEADER *)answerbuf;
qdcount = ntohs(bp->qdcount);
ancount = ntohs(bp->ancount);
nscount = ntohs(bp->nscount);
arcount = ntohs(bp->arcount);
msg = (u_char *)answerbuf;
eom = (u_char *)answerbuf + answerlen;
cp = (u_char *)answerbuf + HFIXEDSZ;
while (qdcount > 0 && cp < eom)
{
cp = skip_qrec(name, cp, msg, eom);
if (cp == NULL)
return(FALSE);
qdcount--;
}
if (qdcount)
{
pr_error("invalid qdcount after %s query for %s",
pr_type(T_NS), name);
h_errno = NO_RECOVERY;
return(FALSE);
}
/*
* If the answer is authoritative, the names are found in the
* answer section, and the nameserver section is empty.
* If not, there may be duplicate names in both sections.
* Addresses are found in the additional info section both cases.
*/
rrcount = ancount + nscount + arcount;
while (rrcount > 0 && cp < eom)
{
char rname[MAXDNAME+1];
char dname[MAXDNAME+1];
int type, class, ttl, dlen;
u_char *eor;
register int n;
struct in_addr inaddr;
n = expand_name(name, T_NONE, cp, msg, eom, rname);
if (n < 0)
return(FALSE);
cp += n;
n = 3*INT16SZ + INT32SZ;
if (check_size(rname, T_NONE, cp, msg, eom, n) < 0)
return(FALSE);
type = _getshort(cp);
cp += INT16SZ;
class = _getshort(cp);
cp += INT16SZ;
ttl = _getlong(cp);
cp += INT32SZ;
dlen = _getshort(cp);
cp += INT16SZ;
eor = cp + dlen;
#ifdef lint
if (verbose)
printf("%-20s\t%d\t%s\t%s\n",
rname, ttl, pr_class(class), pr_type(type));
#endif
if ((type == T_NS) && sameword(rname, name))
{
n = expand_name(rname, type, cp, msg, eom, dname);
if (n < 0)
return(FALSE);
cp += n;
for (i = 0; i < nservers; i++)
if (sameword(nsname[i], dname))
break; /* duplicate */
if (i >= nservers && nservers < MAXNSNAME)
{
(void) strcpy(nsname[nservers], dname);
naddrs[nservers] = 0;
nservers++;
}
}
else if ((type == T_A) && dlen == INADDRSZ)
{
for (i = 0; i < nservers; i++)
if (sameword(nsname[i], rname))
break; /* found */
if (i < nservers && naddrs[i] < MAXIPADDR)
{
bcopy((char *)cp, (char *)&inaddr, INADDRSZ);
ipaddr[i][naddrs[i]] = inaddr;
naddrs[i]++;
}
cp += dlen;
}
else
cp += dlen;
if (cp != eor)
{
pr_error("size error in %s record for %s, off by %s",
pr_type(type), rname, itoa(cp - eor));
return(FALSE);
}
rrcount--;
}
if (rrcount)
{
pr_error("invalid rrcount after %s query for %s",
pr_type(T_NS), name);
h_errno = NO_RECOVERY;
return(FALSE);
}
return(TRUE);
}
/*
** SORT_SERVERS -- Sort set of nameservers according to preference
** ---------------------------------------------------------------
**
** Returns:
** None.
**
** Inputs:
** Set of nameservers as determined by find_servers().
** The global variable ``prefserver'', if set, contains
** a list of preferred server domains to compare against.
**
** Outputs:
** Stores the preferred nameserver order in nsrank[].
*/
void
sort_servers()
{
register int i, j;
register int n, pref;
register char *p, *q;
/*
* Initialize the default ranking.
*/
for (n = 0; n < nservers; n++)
{
nsrank[n] = n;
nspref[n] = 0;
}
/*
* Determine the nameserver preference.
* Compare against a list of comma-separated preferred server domains.
* Use the maximum value of all comparisons.
*/
for (q = NULL, p = prefserver; p != NULL; p = q)
{
q = index(p, ',');
if (q != NULL)
*q = '\0';
for (n = 0; n < nservers; n++)
{
pref = matchlabels(nsname[n], p);
if (pref > nspref[n])
nspref[n] = pref;
}
if (q != NULL)
*q++ = ',';
}
/*
* Sort the set according to preference.
* Keep the rest as much as possible in original order.
*/
for (i = 0; i < nservers; i++)
{
for (j = i + 1; j < nservers; j++)
{
if (nspref[j] > nspref[i])
{
pref = nspref[j];
/* nspref[j] = nspref[i]; */
for (n = j; n > i; n--)
nspref[n] = nspref[n-1];
nspref[i] = pref;
pref = nsrank[j];
/* nsrank[j] = nsrank[i]; */
for (n = j; n > i; n--)
nsrank[n] = nsrank[n-1];
nsrank[i] = pref;
}
}
}
}
/*
** SKIP_TRANSFER -- Check whether a zone transfer should be skipped
** ----------------------------------------------------------------
**
** Returns:
** TRUE if a transfer for this zone should be skipped.
** FALSE if the zone transfer should proceed.
**
** Inputs:
** The global variable ``skipzone'', if set, contains
** a list of zone names to be skipped.
**
** Certain zones are known to contain bogus information, and
** can be requested to be excluded from further processing.
** The zone transfer for such zones and its delegated zones
** will be skipped.
*/
bool
skip_transfer(name)
input char *name; /* name of zone to process */
{
register char *p, *q;
bool skip = FALSE;
for (q = NULL, p = skipzone; p != NULL; p = q)
{
q = index(p, ',');
if (q != NULL)
*q = '\0';
if (sameword(name, p))
skip = TRUE;
if (q != NULL)
*q++ = ',';
}
return(skip);
}
/*
** DO_CHECK -- Check SOA records at each of the nameservers
** --------------------------------------------------------
**
** Returns:
** None.
**
** Inputs:
** The count of nameservers is stored in ``nservers''.
** Names are stored in the nsname[] database.
** Addresses are stored in the ipaddr[] database.
** Address counts are stored in the naddrs[] database.
**
** The SOA record of the zone is checked at each nameserver.
** Nameserver recursion is turned off to make sure that the
** answer is authoritative.
*/
void
do_check(name)
input char *name; /* name of zone to process */
{
res_state_t save_res; /* saved copy of resolver database */
char *save_server; /* saved copy of server name */
register int n;
register int i;
/* save resolver database */
save_res = _res;
save_server = server;
/* turn off nameserver recursion */
_res.options &= ~RES_RECURSE;
for (n = 0; n < nservers; n++)
{
if (naddrs[n] < 1)
continue; /* shortcut */
server = nsname[n];
for (i = 0; i < MAXNS && i < naddrs[n]; i++)
{
nslist(i).sin_family = AF_INET;
nslist(i).sin_port = htons(NAMESERVER_PORT);
nslist(i).sin_addr = ipaddr[n][i];
}
_res.nscount = i;
/* retrieve and check SOA */
if (check_zone(name))
continue;
/* SOA query failed */
ns_error(name, T_SOA, queryclass, server);
/* explicit server failure: possibly data expired */
lameserver = (h_errno == SERVER_FAILURE) ? TRUE : FALSE;
/* non-authoritative denial: assume lame delegation */
if (h_errno == NO_RREC || h_errno == NO_HOST)
lameserver = TRUE;
/* authoritative denial: probably misconfiguration */
if (h_errno == NO_DATA || h_errno == HOST_NOT_FOUND)
lameserver = TRUE;
/* flag an error if server should not have failed */
if (lameserver && authserver)
errmsg("%s has lame delegation to %s",
name, server);
}
/* restore resolver database */
_res = save_res;
server = save_server;
}
/*
** DO_TRANSFER -- Perform a zone transfer from any of its nameservers
** ------------------------------------------------------------------
**
** Returns:
** TRUE if the zone data have been retrieved successfully.
** FALSE if none of the servers responded.
**
** Inputs:
** The count of nameservers is stored in ``nservers''.
** Names are stored in the nsname[] database.
** Addresses are stored in the ipaddr[] database.
** Address counts are stored in the naddrs[] database.
**
** Ask zone transfer to the nameservers, until one responds.
** The list of nameservers is sorted according to preference.
** An authoritative server should always respond positively.
** If it responds with an error, we may have a lame delegation.
** Always retry with the next server to avoid missing entire zones.
*/
bool
do_transfer(name)
input char *name; /* name of zone to do zone xfer for */
{
register int n, ns;
register int i;
for (sort_servers(), ns = 0; ns < nservers; ns++)
{
for (n = nsrank[ns], i = 0; i < naddrs[n]; i++)
{
if (verbose)
printf("Trying server %s (%s) ...\n",
inet_ntoa(ipaddr[n][i]), nsname[n]);
if (transfer_zone(name, queryclass, ipaddr[n][i], nsname[n]))
goto done; /* double break */
/* zone transfer failed */
if ((h_errno != TRY_AGAIN) || verbose)
ns_error(name, T_AXFR, queryclass, nsname[n]);
/* zone transfer request was explicitly refused */
if (h_errno == QUERY_REFUSED)
break;
/* explicit server failure: possibly data expired */
lameserver = (h_errno == SERVER_FAILURE) ? TRUE : FALSE;
/* non-authoritative denial: assume lame delegation */
if (h_errno == NO_RREC || h_errno == NO_HOST)
lameserver = TRUE;
/* authoritative denial: probably misconfiguration */
if (h_errno == NO_DATA || h_errno == HOST_NOT_FOUND)
lameserver = TRUE;
/* flag an error if server should not have failed */
if (lameserver && authserver)
errmsg("%s has lame delegation to %s",
name, nsname[n]);
/* try next server if this one is sick */
if (lameserver)
break;
/* terminate on irrecoverable errors */
if (h_errno != TRY_AGAIN)
return(FALSE);
/* in case nameserver not present */
if (errno == ECONNREFUSED)
break;
}
}
done:
if (ns >= nservers)
{
if ((h_errno == TRY_AGAIN) && !verbose)
ns_error(name, T_AXFR, queryclass, (char *)NULL);
errmsg("No nameservers for %s responded", name);
return(FALSE);
}
return(TRUE);
}
/*
** TRANSFER_ZONE -- Wrapper for get_zone() to hide administrative tasks
** --------------------------------------------------------------------
**
** Returns:
** See get_zone() for details.
**
** Side effects:
** See get_zone() for details.
**
** This routine may be called repeatedly with different server
** addresses, until one of the servers responds. Various items
** must be reset on every try to continue with a clean slate.
*/
bool
transfer_zone(name, class, inaddr, host)
input char *name; /* name of zone to do zone xfer for */
input int class; /* specific resource record class */
input struct in_addr inaddr; /* address of server to be queried */
input char *host; /* name of server to be queried */
{
register int n;
/*
* Reset the resource record statistics before each try.
*/
clear_statistics();
/*
* Reset the hash tables of saved resource record information.
* These tables are used only during the zone transfer itself.
*/
clear_ttltab();
clear_hosttab();
clear_zonetab();
/*
* Perform the actual zone transfer.
*/
if (get_zone(name, class, inaddr, host))
return(TRUE);
/*
* Failure to get the zone. Free any memory that may have been allocated.
* On success it is the responsibility of the caller to free the memory.
* The information gathered is used by list_zone() after the zone transfer.
*/
for (n = 0; n < hostcount; n++)
xfree(hostname[n]);
for (n = 0; n < zonecount; n++)
xfree(zonename[n]);
if (zonename != NULL)
xfree(zonename);
zonename = NULL;
return(FALSE);
}
/*
** GET_ZONE -- Perform a zone transfer from server at specific address
** -------------------------------------------------------------------
**
** Returns:
** TRUE if the zone data have been retrieved successfully.
** FALSE if an error occurred (h_errno is set appropriately).
** Set TRY_AGAIN wherever possible to try the next server.
**
** Side effects:
** Stores list of delegated zones found in zonename[],
** and the count of delegated zones in ``zonecount''.
** Stores list of host names found in hostname[],
** and the count of host names in ``hostcount''.
** Updates resource record statistics in record_stats[].
** This array must have been cleared before.
*/
bool
get_zone(name, class, inaddr, host)
input char *name; /* name of zone to do zone xfer for */
input int class; /* specific resource record class */
input struct in_addr inaddr; /* address of server to be queried */
input char *host; /* name of server to be queried */
{
querybuf query;
querybuf answer;
HEADER *bp;
int ancount;
int sock;
struct sockaddr_in sin;
register int n;
register int i;
int nrecords = 0; /* number of records processed */
int soacount = 0; /* count of SOA records */
zonecount = 0; /* count of delegated zones */
hostcount = 0; /* count of host names */
/*
* Construct query, and connect to the given server.
*/
errno = 0; /* reset before querying nameserver */
n = res_mkquery(QUERY, name, class, T_AXFR, (qbuf_t *)NULL, 0,
(rrec_t *)NULL, (qbuf_t *)&query, sizeof(querybuf));
if (n < 0)
{
if (debug)
printf("%sres_mkquery failed\n", dbprefix);
h_errno = NO_RECOVERY;
return(FALSE);
}
if (debug)
{
printf("%sget_zone()\n", dbprefix);
pr_query((qbuf_t *)&query, n, stdout);
}
sin.sin_family = AF_INET;
sin.sin_port = htons(NAMESERVER_PORT);
sin.sin_addr = inaddr;
/* add name and address to error messages */
/* _res_setaddr(&sin, host); */
sock = socket(AF_INET, SOCK_STREAM, 0);
if (sock < 0)
{
_res_perror(&sin, host, "socket");
h_errno = TRY_AGAIN;
return(FALSE);
}
if (_res_connect(sock, &sin, sizeof(sin)) < 0)
{
if (debug || verbose)
_res_perror(&sin, host, "connect");
(void) close(sock);
h_errno = TRY_AGAIN;
return(FALSE);
}
if (verbose)
printf("Asking zone transfer for %s ...\n", name);
/*
* Send the query buffer.
*/
if (_res_write(sock, &sin, host, (char *)&query, n) < 0)
{
(void) close(sock);
h_errno = TRY_AGAIN;
return(FALSE);
}
/*
* Process all incoming records, each record in a separate packet.
*/
while ((n = _res_read(sock, &sin, host, (char *)&answer, sizeof(querybuf))) != 0)
{
if (n < 0)
{
(void) close(sock);
h_errno = TRY_AGAIN;
return(FALSE);
}
errno = 0; /* reset after we got an answer */
if (n < HFIXEDSZ)
{
pr_error("answer length %s too short during %s for %s from %s",
itoa(n), pr_type(T_AXFR), name, host);
(void) close(sock);
h_errno = TRY_AGAIN;
return(FALSE);
}
if (debug > 1)
{
printf("%sgot answer, %d bytes:\n", dbprefix, n);
pr_query((qbuf_t *)&answer, n, stdout);
}
/*
* Analyze the contents of the answer and check for errors.
* An error can be expected only in the very first packet.
* The query section should be empty except in the first packet.
* Note the special error status codes for specific failures.
*/
bp = (HEADER *)&answer;
ancount = ntohs(bp->ancount);
if (bp->rcode != NOERROR || ancount == 0)
{
if (debug || verbose)
print_status(&answer);
switch (bp->rcode)
{
case NXDOMAIN:
/* distinguish between authoritative or not */
h_errno = bp->aa ? HOST_NOT_FOUND : NO_HOST;
break;
case NOERROR:
/* distinguish between authoritative or not */
h_errno = bp->aa ? NO_DATA : NO_RREC;
break;
case REFUSED:
/* special status if zone transfer refused */
h_errno = QUERY_REFUSED;
break;
case SERVFAIL:
/* special status upon explicit failure */
h_errno = SERVER_FAILURE;
break;
default:
/* all other errors will cause a retry */
h_errno = TRY_AGAIN;
break;
}
if (nrecords != 0)
pr_error("unexpected error during %s for %s from %s",
pr_type(T_AXFR), name, host);
(void) close(sock);
return(FALSE);
}
h_errno = 0;
/*
* The nameserver and additional info section should be empty,
* and there should be a single answer in the answer section.
*/
if (ancount != 1)
pr_error("multiple answers during %s for %s from %s",
pr_type(T_AXFR), name, host);
i = ntohs(bp->nscount);
if (i != 0)
pr_error("nonzero nscount during %s for %s from %s",
pr_type(T_AXFR), name, host);
i = ntohs(bp->arcount);
if (i != 0)
pr_error("nonzero arcount during %s for %s from %s",
pr_type(T_AXFR), name, host);
/*
* Valid packet received. Print contents if appropriate.
*/
nrecords++;
soaname = NULL, subname = NULL, adrname = NULL;
listhost = host;
(void) print_info(&answer, n, name, T_AXFR, TRUE);
/*
* Terminate upon the second SOA record for this zone.
*/
if (soaname && sameword(soaname, name) && soacount++)
break;
/* the nameserver balks on this one */
if (soaname && !sameword(soaname, name))
pr_warning("extraneous SOA record for %s within %s from %s",
soaname, name, host);
/*
* Save encountered delegated zone name for recursive listing.
*/
if (subname && indomain(subname, name, FALSE))
{
i = zone_index(subname, TRUE);
#ifdef obsolete
for (i = 0; i < zonecount; i++)
if (sameword(zonename[i], subname))
break; /* duplicate */
#endif
if (i >= zonecount)
{
zonename = newlist(zonename, zonecount+1, char *);
zonename[zonecount] = newstr(subname);
zonecount++;
}
}
/* warn about strange delegated zones */
else if (subname && !indomain(subname, name, TRUE))
pr_warning("extraneous NS record for %s within %s from %s",
subname, name, host);
/*
* Save encountered name of A record for host name count.
*/
if (adrname && indomain(adrname, name, FALSE) && !reverse)
{
i = host_index(adrname, (hostcount < MAXHOSTS));
#ifdef obsolete
for (i = 0; i < hostcount; i++)
if (sameword(hostname[i], adrname))
break; /* duplicate */
#endif
if (i < hostcount && address != hostaddr[i])
multaddr[i] = TRUE;
if (i >= hostcount && hostcount < MAXHOSTS)
{
hostname[hostcount] = newstr(adrname);
hostaddr[hostcount] = address;
multaddr[hostcount] = FALSE;
hostcount++;
if (hostcount == MAXHOSTS)
pr_error("maximum %s hosts reached within %s from %s",
itoa(hostcount), name, host);
}
}
/* check for unauthoritative glue records */
else if (adrname && !indomain(adrname, name, TRUE))
pr_warning("extraneous glue record for %s within %s from %s",
adrname, name, host);
}
/*
* End of zone transfer at second SOA record or zero length read.
*/
(void) close(sock);
/*
* Check for the anomaly that the whole transfer consisted of the
* SOA records only. Could occur if we queried the victim of a lame
* delegation which happened to have the SOA record present.
*/
if (nrecords <= soacount)
{
pr_error("empty zone transfer for %s from %s",
name, host);
h_errno = NO_RREC;
return(FALSE);
}
/*
* Do an extra check for delegated zones that also have an A record.
* Those may have been defined in the child zone, and crept in the
* parent zone, or may have been defined as glue records.
* This is not necessarily an error, but the host count may be wrong.
* Note that an A record for the current zone has been ignored above.
*/
for (n = 0; n < zonecount; n++)
{
i = host_index(zonename[n], FALSE);
#ifdef obsolete
for (i = 0; i < hostcount; i++)
if (sameword(hostname[i], zonename[n]))
break; /* found */
#endif
if (i < hostcount)
pr_warning("%s has both NS and A records within %s from %s",
zonename[n], name, host);
}
/*
* The zone transfer has been successful.
*/
if (verbose)
printf("Transfer complete, %d records received for %s\n",
nrecords, name);
return(TRUE);
}
/*
** GET_MXREC -- Fetch MX records of a domain
** -----------------------------------------
**
** Returns:
** TRUE if MX records were found.
** FALSE otherwise.
*/
bool
get_mxrec(name)
input char *name; /* domain name to get mx for */
{
querybuf answer;
register int n;
if (verbose)
printf("Finding MX records for %s ...\n", name);
n = get_info(&answer, name, T_MX, queryclass);
if (n < 0)
return(FALSE);
(void) print_info(&answer, n, name, T_MX, FALSE);
return(TRUE);
}
/*
** GET_PRIMARY -- Fetch name of primary nameserver for a zone
** ----------------------------------------------------------
**
** Returns:
** Pointer to the name of the primary server, if found.
** NULL if the server could not be determined.
*/
char *
get_primary(name)
input char *name; /* name of zone to get soa for */
{
querybuf answer;
register int n;
if (verbose)
printf("Finding primary nameserver for %s ...\n", name);
n = get_info(&answer, name, T_SOA, queryclass);
if (n < 0)
return(NULL);
if (verbose > 1)
(void) print_info(&answer, n, name, T_SOA, FALSE);
soaname = NULL;
(void) get_soainfo(&answer, n, name);
if (soaname == NULL)
return(NULL);
return(soa.primary);
}
/*
** CHECK_ZONE -- Fetch and analyze SOA record of a zone
** ----------------------------------------------------
**
** Returns:
** TRUE if the SOA record was found at the given server.
** FALSE otherwise.
**
** Inputs:
** The global variable ``server'' must contain the name
** of the server that was queried.
*/
bool
check_zone(name)
input char *name; /* name of zone to get soa for */
{
querybuf answer;
register int n;
if (verbose)
printf("Checking SOA for %s at server %s ...\n", name, server);
else if (authserver)
printf("%-20s\tNS\t%s\n", name, server);
else
printf("%s\t(%s)\n", name, server);
n = get_info(&answer, name, T_SOA, queryclass);
if (n < 0)
return(FALSE);
if (verbose > 1)
(void) print_info(&answer, n, name, T_SOA, FALSE);
soaname = NULL;
(void) get_soainfo(&answer, n, name);
if (soaname == NULL)
return(FALSE);
check_soa(&answer, name);
return(TRUE);
}
/*
** GET_SOAINFO -- Extract SOA data from nameserver answer buffer
** -------------------------------------------------------------
**
** Returns:
** TRUE if the SOA record was found successfully.
** FALSE otherwise.
**
** Outputs:
** The global struct ``soa'' is filled with the soa data.
**
** Side effects:
** Sets ``soaname'' if this is a valid SOA record.
** This variable must have been cleared before calling
** get_soainfo() and may be checked afterwards.
*/
bool
get_soainfo(answerbuf, answerlen, name)
input querybuf *answerbuf; /* location of answer buffer */
input int answerlen; /* length of answer buffer */
input char *name; /* name of zone to get soa for */
{
HEADER *bp;
int qdcount, ancount;
u_char *msg, *eom;
register u_char *cp;
bp = (HEADER *)answerbuf;
qdcount = ntohs(bp->qdcount);
ancount = ntohs(bp->ancount);
msg = (u_char *)answerbuf;
eom = (u_char *)answerbuf + answerlen;
cp = (u_char *)answerbuf + HFIXEDSZ;
while (qdcount > 0 && cp < eom)
{
cp = skip_qrec(name, cp, msg, eom);
if (cp == NULL)
return(FALSE);
qdcount--;
}
if (qdcount)
{
pr_error("invalid qdcount after %s query for %s",
pr_type(T_SOA), name);
h_errno = NO_RECOVERY;
return(FALSE);
}
/*
* Check answer section only.
* The nameserver section may contain the nameservers for the zone,
* and the additional section their addresses, but not guaranteed.
* Those sections are usually empty for authoritative answers.
*/
while (ancount > 0 && cp < eom)
{
char rname[MAXDNAME+1];
int type, class, ttl, dlen;
u_char *eor;
register int n;
n = expand_name(name, T_NONE, cp, msg, eom, rname);
if (n < 0)
return(FALSE);
cp += n;
n = 3*INT16SZ + INT32SZ;
if (check_size(rname, T_NONE, cp, msg, eom, n) < 0)
return(FALSE);
type = _getshort(cp);
cp += INT16SZ;
class = _getshort(cp);
cp += INT16SZ;
ttl = _getlong(cp);
cp += INT32SZ;
dlen = _getshort(cp);
cp += INT16SZ;
eor = cp + dlen;
#ifdef lint
if (verbose)
printf("%-20s\t%d\t%s\t%s\n",
rname, ttl, pr_class(class), pr_type(type));
#endif
switch (type)
{
case T_SOA:
n = expand_name(rname, type, cp, msg, eom, soa.primary);
if (n < 0)
return(FALSE);
cp += n;
n = expand_name(rname, type, cp, msg, eom, soa.hostmaster);
if (n < 0)
return(FALSE);
cp += n;
n = 5*INT32SZ;
if (check_size(rname, type, cp, msg, eor, n) < 0)
return(FALSE);
soa.serial = _getlong(cp);
cp += INT32SZ;
soa.refresh = _getlong(cp);
cp += INT32SZ;
soa.retry = _getlong(cp);
cp += INT32SZ;
soa.expire = _getlong(cp);
cp += INT32SZ;
soa.defttl = _getlong(cp);
cp += INT32SZ;
/* valid complete soa record found */
soaname = strcpy(soanamebuf, rname);
break;
default:
cp += dlen;
break;
}
if (cp != eor)
{
pr_error("size error in %s record for %s, off by %s",
pr_type(type), rname, itoa(cp - eor));
return(FALSE);
}
ancount--;
}
if (ancount)
{
pr_error("invalid ancount after %s query for %s",
pr_type(T_SOA), name);
h_errno = NO_RECOVERY;
return(FALSE);
}
return(TRUE);
}
/*
** CHECK_SOA -- Analyze retrieved SOA records of a zone
** ----------------------------------------------------
**
** Returns:
** None.
**
** Inputs:
** The global variable ``server'' must contain the
** name of the server that was queried.
** The global struct ``soa'' must contain the soa data.
*/
void
check_soa(answerbuf, name)
input querybuf *answerbuf; /* location of answer buffer */
input char *name; /* name of zone to check soa for */
{
static char oldnamebuf[MAXDNAME+1];
static char *oldname = NULL; /* previous name of zone */
static char *oldserver = NULL; /* previous name of server */
static soa_data_t oldsoa; /* previous soa data */
register int n;
HEADER *bp;
/*
* Print the various SOA fields in abbreviated form.
* Values are actually unsigned, but we print them as signed integers,
* apart from the serial which really becomes that big sometimes.
* In the latter case we print a warning below.
*/
printf("%s\t%s\t(%u %d %d %d %d)\n",
soa.primary, soa.hostmaster, (unsigned)soa.serial,
soa.refresh, soa.retry, soa.expire, soa.defttl);
/*
* We are supposed to have queried an authoritative nameserver, and since
* nameserver recursion has been turned off, answer must be authoritative.
*/
bp = (HEADER *)answerbuf;
if (!bp->aa)
{
if (authserver)
pr_error("%s SOA record at %s is not authoritative",
name, server);
else
pr_warning("%s SOA record at %s is not authoritative",
name, server);
if (authserver)
errmsg("%s has lame delegation to %s",
name, server);
}
/*
* Check whether we are switching to a new zone.
* The old name must have been saved in static storage.
*/
if ((oldname != NULL) && !sameword(name, oldname))
oldname = NULL;
/*
* Make few timer consistency checks only for the first one in a series.
* Compare the primary field against the list of authoritative servers.
* Explicitly check the hostmaster field for illegal characters ('@').
* Yell if the serial has the high bit set (not always intentional).
*/
if (oldname == NULL)
{
for (n = 0; n < nservers; n++)
if (sameword(soa.primary, nsname[n]))
break; /* found */
if ((n >= nservers) && authserver)
pr_warning("%s SOA primary %s is not advertised via NS",
name, soa.primary);
if (!valid_name(soa.primary, FALSE, FALSE, FALSE))
pr_warning("%s SOA primary %s has illegal name",
name, soa.primary);
if (!valid_name(soa.hostmaster, FALSE, TRUE, FALSE))
pr_warning("%s SOA hostmaster %s has illegal mailbox",
name, soa.hostmaster);
if (bitset(0x80000000, soa.serial))
pr_warning("%s SOA serial has high bit set",
name);
if (soa.retry > soa.refresh)
pr_warning("%s SOA retry exceeds refresh",
name);
if (soa.refresh + soa.retry > soa.expire)
pr_warning("%s SOA refresh+retry exceeds expire",
name);
}
/*
* Compare various fields with those of the previous query, if any.
* Different serial numbers may be present if secondaries have not yet
* refreshed the data from the primary. Issue only a warning in that case.
*/
if (oldname != NULL)
{
if (!sameword(soa.primary, oldsoa.primary))
pr_error("%s and %s have different primary for %s",
server, oldserver, name);
if (!sameword(soa.hostmaster, oldsoa.hostmaster))
pr_error("%s and %s have different hostmaster for %s",
server, oldserver, name);
if (soa.serial != oldsoa.serial)
pr_warning("%s and %s have different serial for %s",
server, oldserver, name);
if (soa.refresh != oldsoa.refresh)
pr_error("%s and %s have different refresh for %s",
server, oldserver, name);
if (soa.retry != oldsoa.retry)
pr_error("%s and %s have different retry for %s",
server, oldserver, name);
if (soa.expire != oldsoa.expire)
pr_error("%s and %s have different expire for %s",
server, oldserver, name);
if (soa.defttl != oldsoa.defttl)
pr_error("%s and %s have different defttl for %s",
server, oldserver, name);
}
/*
* Save the current information.
*/
oldname = strcpy(oldnamebuf, name);
oldserver = server;
oldsoa = soa;
}
/*
** CHECK_DUPL -- Check global address list for duplicates
** ------------------------------------------------------
**
** Returns:
** TRUE if the given host address already exists.
** FALSE otherwise.
**
** Side effects:
** Adds the host address to the list if not present.
**
** The information in this table is global, and is not cleared.
*/
#define AHASHSIZE 0x2000
#define AHASHMASK 0x1fff
typedef struct addr_tab {
ipaddr_t *addrlist; /* global list of addresses */
int addrcount; /* count of global addresses */
} addr_tab_t;
addr_tab_t addrtab[AHASHSIZE]; /* hash list of global addresses */
bool
check_dupl(addr)
input ipaddr_t addr; /* address of host to check */
{
register int i;
register addr_tab_t *s;
s = &addrtab[ntohl(addr) & AHASHMASK];
for (i = 0; i < s->addrcount; i++)
if (s->addrlist[i] == addr)
return(TRUE); /* duplicate */
s->addrlist = newlist(s->addrlist, s->addrcount+1, ipaddr_t);
s->addrlist[s->addrcount] = addr;
s->addrcount++;
return(FALSE);
}
/*
** CHECK_TTL -- Check list of records for different ttl values
** -----------------------------------------------------------
**
** Returns:
** TRUE if the ttl value matches the first record
** already listed with the same name/type/class.
** FALSE only when the first discrepancy is found.
**
** Side effects:
** Adds the record data to the list if not present.
*/
#define THASHSIZE 2003
typedef struct ttl_tab {
struct ttl_tab *next; /* next entry in chain */
char *name; /* name of resource record */
int type; /* resource record type */
int class; /* resource record class */
int ttl; /* time_to_live value */
int count; /* count of different ttl values */
} ttl_tab_t;
ttl_tab_t *ttltab[THASHSIZE]; /* hash list of record info */
bool
check_ttl(name, type, class, ttl)
input char *name; /* resource record name */
input int type, class, ttl; /* resource record fixed values */
{
register ttl_tab_t *s;
register ttl_tab_t **ps;
register unsigned int hfunc;
register char *p;
register char c;
/*
* Compute the hash function for this resource record.
* Look it up in the appropriate hash chain.
*/
for (hfunc = type, p = name; (c = *p) != '\0'; p++)
{
hfunc = ((hfunc << 1) ^ (lower(c) & 0377)) % THASHSIZE;
}
for (ps = &ttltab[hfunc]; (s = *ps) != NULL; ps = &s->next)
{
if (s->type != type || s->class != class)
continue;
if (sameword(s->name, name))
break;
}
/*
* Allocate new entry if not found.
*/
if (s == NULL)
{
/* ps = &ttltab[hfunc]; */
s = newlist(NULL, 1, ttl_tab_t);
/* initialize new entry */
s->name = newstr(name);
s->type = type;
s->class = class;
s->ttl = ttl;
s->count = 0;
/* link it in */
s->next = *ps;
*ps = s;
}
/*
* Check whether the ttl value matches the first recorded one.
* If not, signal only the first discrepancy encountered, so
* only one warning message will be printed.
*/
if (s->ttl == ttl)
return(TRUE);
s->count += 1;
return((s->count == 1) ? FALSE : TRUE);
}
/*
** CLEAR_TTLTAB -- Clear resource record list for ttl checking
** -----------------------------------------------------------
**
** Returns:
** None.
**
** An entry on the hash list, and the host name in each
** entry, have been allocated in dynamic memory.
**
** The information in this table is on a per-zone basis.
** It must be cleared before any subsequent zone transfers.
*/
void
clear_ttltab()
{
register int i;
register ttl_tab_t *s, *t;
for (i = 0; i < THASHSIZE; i++)
{
if (ttltab[i] != NULL)
{
/* free chain of entries */
for (t = NULL, s = ttltab[i]; s != NULL; s = t)
{
t = s->next;
xfree(s->name);
xfree(s);
}
/* reset hash chain */
ttltab[i] = NULL;
}
}
}
/*
** HOST_INDEX -- Check list of host names for name being present
** -------------------------------------------------------------
**
** Returns:
** Index into hostname[] table, if found.
** Current ``hostcount'' value, if not found.
**
** Side effects:
** May add an entry to the hash list if not present.
**
** A linear search through the master table becomes very
** costly for zones with more than a few thousand hosts.
** Maintain a hash list with indexes into the master table.
** Caller should update the master table after this call.
*/
#define HHASHSIZE 2003
typedef struct host_tab {
struct host_tab *next; /* next entry in chain */
int slot; /* slot in host name table */
} host_tab_t;
host_tab_t *hosttab[HHASHSIZE]; /* hash list of host name info */
int
host_index(name, enter)
input char *name; /* the host name to check */
input bool enter; /* add to table if not found */
{
register host_tab_t *s;
register host_tab_t **ps;
register unsigned int hfunc;
register char *p;
register char c;
/*
* Compute the hash function for this host name.
* Look it up in the appropriate hash chain.
*/
for (hfunc = 0, p = name; (c = *p) != '\0'; p++)
{
hfunc = ((hfunc << 1) ^ (lower(c) & 0377)) % HHASHSIZE;
}
for (ps = &hosttab[hfunc]; (s = *ps) != NULL; ps = &s->next)
{
if (s->slot >= hostcount)
continue;
if (sameword(hostname[s->slot], name))
break;
}
/*
* Allocate new entry if not found.
*/
if ((s == NULL) && enter)
{
/* ps = &hosttab[hfunc]; */
s = newlist(NULL, 1, host_tab_t);
/* initialize new entry */
s->slot = hostcount;
/* link it in */
s->next = *ps;
*ps = s;
}
return((s != NULL) ? s->slot : hostcount);
}
/*
** CLEAR_HOSTTAB -- Clear hash list for host name checking
** -------------------------------------------------------
**
** Returns:
** None.
**
** A hash list entry has been allocated in dynamic memory.
**
** The information in this table is on a per-zone basis.
** It must be cleared before any subsequent zone transfers.
*/
void
clear_hosttab()
{
register int i;
register host_tab_t *s, *t;
for (i = 0; i < HHASHSIZE; i++)
{
if (hosttab[i] != NULL)
{
/* free chain of entries */
for (t = NULL, s = hosttab[i]; s != NULL; s = t)
{
t = s->next;
xfree(s);
}
/* reset hash chain */
hosttab[i] = NULL;
}
}
}
/*
** ZONE_INDEX -- Check list of zone names for name being present
** -------------------------------------------------------------
**
** Returns:
** Index into zonename[] table, if found.
** Current ``zonecount'' value, if not found.
**
** Side effects:
** May add an entry to the hash list if not present.
**
** A linear search through the master table becomes very
** costly for more than a few thousand delegated zones.
** Maintain a hash list with indexes into the master table.
** Caller should update the master table after this call.
*/
#define ZHASHSIZE 2003
typedef struct zone_tab {
struct zone_tab *next; /* next entry in chain */
int slot; /* slot in zone name table */
} zone_tab_t;
zone_tab_t *zonetab[ZHASHSIZE]; /* hash list of zone name info */
int
zone_index(name, enter)
input char *name; /* the zone name to check */
input bool enter; /* add to table if not found */
{
register zone_tab_t *s;
register zone_tab_t **ps;
register unsigned int hfunc;
register char *p;
register char c;
/*
* Compute the hash function for this zone name.
* Look it up in the appropriate hash chain.
*/
for (hfunc = 0, p = name; (c = *p) != '\0'; p++)
{
hfunc = ((hfunc << 1) ^ (lower(c) & 0377)) % ZHASHSIZE;
}
for (ps = &zonetab[hfunc]; (s = *ps) != NULL; ps = &s->next)
{
if (s->slot >= zonecount)
continue;
if (sameword(zonename[s->slot], name))
break;
}
/*
* Allocate new entry if not found.
*/
if ((s == NULL) && enter)
{
/* ps = &zonetab[hfunc]; */
s = newlist(NULL, 1, zone_tab_t);
/* initialize new entry */
s->slot = zonecount;
/* link it in */
s->next = *ps;
*ps = s;
}
return((s != NULL) ? s->slot : zonecount);
}
/*
** CLEAR_ZONETAB -- Clear hash list for zone name checking
** -------------------------------------------------------
**
** Returns:
** None.
**
** A hash list entry has been allocated in dynamic memory.
**
** The information in this table is on a per-zone basis.
** It must be cleared before any subsequent zone transfers.
*/
void
clear_zonetab()
{
register int i;
register zone_tab_t *s, *t;
for (i = 0; i < ZHASHSIZE; i++)
{
if (zonetab[i] != NULL)
{
/* free chain of entries */
for (t = NULL, s = zonetab[i]; s != NULL; s = t)
{
t = s->next;
xfree(s);
}
/* reset hash chain */
zonetab[i] = NULL;
}
}
}
/*
** CHECK_CANON -- Check list of domain names for name being canonical
** ------------------------------------------------------------------
**
** Returns:
** Nonzero if the name is definitely not canonical.
** 0 if it is canonical, or if it remains undecided.
**
** Side effects:
** Adds the domain name to the list if not present.
**
** The information in this table is global, and is not cleared
** (which may be necessary if the checking algorithm changes).
*/
#define CHASHSIZE 2003
typedef struct canon_tab {
struct canon_tab *next; /* next entry in chain */
char *name; /* domain name */
int status; /* nonzero if not canonical */
} canon_tab_t;
canon_tab_t *canontab[CHASHSIZE]; /* hash list of domain name info */
int
check_canon(name)
input char *name; /* the domain name to check */
{
register canon_tab_t *s;
register canon_tab_t **ps;
register unsigned int hfunc;
register char *p;
register char c;
/*
* Compute the hash function for this domain name.
* Look it up in the appropriate hash chain.
*/
for (hfunc = 0, p = name; (c = *p) != '\0'; p++)
{
hfunc = ((hfunc << 1) ^ (lower(c) & 0377)) % CHASHSIZE;
}
for (ps = &canontab[hfunc]; (s = *ps) != NULL; ps = &s->next)
{
if (sameword(s->name, name))
break;
}
/*
* Allocate new entry if not found.
* Only then is the actual check carried out.
*/
if (s == NULL)
{
/* ps = &canontab[hfunc]; */
s = newlist(NULL, 1, canon_tab_t);
/* initialize new entry */
s->name = newstr(name);
s->status = canonical(name);
/* link it in */
s->next = *ps;
*ps = s;
}
return(s->status);
}
/*
** CHECK_ADDR -- Check whether reverse address mappings revert to host
** -------------------------------------------------------------------
**
** Returns:
** TRUE if all addresses of host map back to host.
** FALSE otherwise.
*/
bool
check_addr(name)
input char *name; /* host name to check addresses for */
{
struct hostent *hp;
register int i;
struct in_addr inaddr[MAXADDRS];
int naddr;
char hnamebuf[MAXDNAME+1];
char *hname;
char inamebuf[MAXDNAME+1];
char *iname;
int matched;
/*
* Look up the specified host to fetch its addresses.
*/
hp = gethostbyname(name);
if (hp == NULL)
{
ns_error(name, T_A, C_IN, server);
return(FALSE);
}
hname = strcpy(hnamebuf, hp->h_name);
for (i = 0; i < MAXADDRS && hp->h_addr_list[i]; i++)
inaddr[i] = incopy(hp->h_addr_list[i]);
naddr = i;
if (verbose)
printf("Found %d address%s for %s\n",
naddr, plurale(naddr), hname);
/*
* Map back the addresses found, and check whether they revert to host.
*/
for (matched = 0, i = 0; i < naddr; i++)
{
iname = strcpy(inamebuf, inet_ntoa(inaddr[i]));
if (verbose)
printf("Checking %s address %s\n", hname, iname);
hp = gethostbyaddr((char *)&inaddr[i], INADDRSZ, AF_INET);
if (hp == NULL)
ns_error(iname, T_PTR, C_IN, server);
else if (!sameword(hp->h_name, hname))
pr_warning("%s address %s maps to %s",
hname, iname, hp->h_name);
else
matched++;
}
return((matched == naddr) ? TRUE : FALSE);
}
/*
** CHECK_NAME -- Check whether address belongs to host addresses
** -------------------------------------------------------------
**
** Returns:
** TRUE if given address was found among host addresses.
** FALSE otherwise.
*/
bool
check_name(addr)
input ipaddr_t addr; /* address of host to check */
{
struct hostent *hp;
register int i;
struct in_addr inaddr;
char hnamebuf[MAXDNAME+1];
char *hname;
char inamebuf[MAXDNAME+1];
char *iname;
int matched;
/*
* Check whether the address is registered by fetching its host name.
*/
inaddr.s_addr = addr;
iname = strcpy(inamebuf, inet_ntoa(inaddr));
hp = gethostbyaddr((char *)&inaddr, INADDRSZ, AF_INET);
if (hp == NULL)
{
ns_error(iname, T_PTR, C_IN, server);
return(FALSE);
}
hname = strcpy(hnamebuf, hp->h_name);
if (verbose)
printf("Address %s maps to %s\n", iname, hname);
/*
* Lookup the host name found to fetch its addresses.
* Verify whether the mapped host name is canonical.
*/
hp = gethostbyname(hname);
if (hp == NULL)
{
ns_error(hname, T_A, C_IN, server);
return(FALSE);
}
if (!sameword(hp->h_name, hname))
pr_warning("%s host %s is not canonical (%s)",
iname, hname, hp->h_name);
/*
* Check whether the given address is listed among the known addresses.
*/
for (matched = 0, i = 0; hp->h_addr_list[i]; i++)
{
inaddr = incopy(hp->h_addr_list[i]);
if (verbose)
printf("Checking %s address %s\n",
hname, inet_ntoa(inaddr));
if (inaddr.s_addr == addr)
matched++;
}
if (!matched)
pr_error("address %s does not belong to %s",
iname, hname);
return(matched ? TRUE : FALSE);
}
/*
** PARSE_TYPE -- Decode rr type from input string
** ----------------------------------------------
**
** Returns:
** Value of resource record type.
** -1 if specified record name is invalid.
**
** Note. T_MD, T_MF, T_MAILA are obsolete, but recognized.
** T_AXFR is not allowed to be specified as query type.
*/
int
parse_type(str)
input char *str; /* input string with record type */
{
register int type;
if (sameword(str, "A")) return(T_A);
if (sameword(str, "NS")) return(T_NS);
if (sameword(str, "MD")) return(T_MD); /* obsolete */
if (sameword(str, "MF")) return(T_MF); /* obsolete */
if (sameword(str, "CNAME")) return(T_CNAME);
if (sameword(str, "SOA")) return(T_SOA);
if (sameword(str, "MB")) return(T_MB);
if (sameword(str, "MG")) return(T_MG);
if (sameword(str, "MR")) return(T_MR);
if (sameword(str, "NULL")) return(T_NULL);
if (sameword(str, "WKS")) return(T_WKS);
if (sameword(str, "PTR")) return(T_PTR);
if (sameword(str, "HINFO")) return(T_HINFO);
if (sameword(str, "MINFO")) return(T_MINFO);
if (sameword(str, "MX")) return(T_MX);
if (sameword(str, "TXT")) return(T_TXT);
if (sameword(str, "RP")) return(T_RP);
if (sameword(str, "AFSDB")) return(T_AFSDB);
if (sameword(str, "X25")) return(T_X25);
if (sameword(str, "ISDN")) return(T_ISDN);
if (sameword(str, "RT")) return(T_RT);
if (sameword(str, "NSAP")) return(T_NSAP);
if (sameword(str, "NSAP-PTR")) return(T_NSAPPTR);
if (sameword(str, "SIG")) return(T_SIG);
if (sameword(str, "KEY")) return(T_KEY);
if (sameword(str, "PX")) return(T_PX);
if (sameword(str, "GPOS")) return(T_GPOS);
if (sameword(str, "AAAA")) return(T_AAAA);
if (sameword(str, "LOC")) return(T_LOC);
if (sameword(str, "UINFO")) return(T_UINFO);
if (sameword(str, "UID")) return(T_UID);
if (sameword(str, "GID")) return(T_GID);
if (sameword(str, "UNSPEC")) return(T_UNSPEC);
if (sameword(str, "AXFR")) return(-1); /* illegal */
if (sameword(str, "MAILB")) return(T_MAILB);
if (sameword(str, "MAILA")) return(T_MAILA); /* obsolete */
if (sameword(str, "ANY")) return(T_ANY);
if (sameword(str, "*")) return(T_ANY);
type = atoi(str);
if (type >= T_FIRST && type <= T_LAST)
return(type);
return(-1);
}
/*
** PARSE_CLASS -- Decode rr class from input string
** ------------------------------------------------
**
** Returns:
** Value of resource class.
** -1 if specified class name is invalid.
**
** Note. C_CSNET is obsolete, but recognized.
*/
int
parse_class(str)
input char *str; /* input string with resource class */
{
register int class;
if (sameword(str, "IN")) return(C_IN);
if (sameword(str, "INTERNET")) return(C_IN);
if (sameword(str, "CS")) return(C_CSNET); /* obsolete */
if (sameword(str, "CSNET")) return(C_CSNET); /* obsolete */
if (sameword(str, "CH")) return(C_CHAOS);
if (sameword(str, "CHAOS")) return(C_CHAOS);
if (sameword(str, "HS")) return(C_HS);
if (sameword(str, "HESIOD")) return(C_HS);
if (sameword(str, "ANY")) return(C_ANY);
if (sameword(str, "*")) return(C_ANY);
class = atoi(str);
if (class > 0)
return(class);
return(-1);
}
/*
** IN_ADDR_ARPA -- Convert dotted quad string to reverse in-addr.arpa
** ------------------------------------------------------------------
**
** Returns:
** Pointer to appropriate reverse in-addr.arpa name
** with trailing dot to force absolute domain name.
** NULL in case of invalid dotted quad input string.
*/
char *
in_addr_arpa(dottedquad)
input char *dottedquad; /* input string with dotted quad */
{
static char addrbuf[4*4 + sizeof(ARPA_ROOT) + 2];
unsigned int a[4];
register int n;
n = sscanf(dottedquad, "%u.%u.%u.%u", &a[0], &a[1], &a[2], &a[3]);
switch (n)
{
case 4:
(void) sprintf(addrbuf, "%u.%u.%u.%u.%s.",
a[3]&0xff, a[2]&0xff, a[1]&0xff, a[0]&0xff, ARPA_ROOT);
break;
case 3:
(void) sprintf(addrbuf, "%u.%u.%u.%s.",
a[2]&0xff, a[1]&0xff, a[0]&0xff, ARPA_ROOT);
break;
case 2:
(void) sprintf(addrbuf, "%u.%u.%s.",
a[1]&0xff, a[0]&0xff, ARPA_ROOT);
break;
case 1:
(void) sprintf(addrbuf, "%u.%s.",
a[0]&0xff, ARPA_ROOT);
break;
default:
return(NULL);
}
while (--n >= 0)
if (a[n] > 255)
return(NULL);
return(addrbuf);
}
/*
** NSAP_INT -- Convert dotted nsap address string to reverse nsap.int
** ------------------------------------------------------------------
**
** Returns:
** Pointer to appropriate reverse nsap.int name
** with trailing dot to force absolute domain name.
** NULL in case of invalid nsap address input string.
*/
char *
nsap_int(name)
input char *name; /* input string with dotted nsap */
{
static char addrbuf[4*MAXNSAP + sizeof(NSAP_ROOT) + 2];
register int n;
register int i;
/* skip optional leading hex indicator */
if (samehead(name, "0x"))
name += 2;
for (n = 0, i = strlength(name)-1; i >= 0; --i)
{
/* skip optional interspersed separators */
if (name[i] == '.' || name[i] == '+' || name[i] == '/')
continue;
/* must consist of hex digits only */
if (!is_xdigit(name[i]))
return(NULL);
/* but not too many */
if (n >= 4*MAXNSAP)
return(NULL);
addrbuf[n++] = name[i];
addrbuf[n++] = '.';
}
/* must have an even number of hex digits */
if (n == 0 || (n % 4) != 0)
return(NULL);
(void) sprintf(&addrbuf[n], "%s.", NSAP_ROOT);
return(addrbuf);
}
/*
** PRINT_HOST -- Print host name and address of hostent struct
** -----------------------------------------------------------
**
** Returns:
** None.
*/
void
print_host(heading, hp)
input char *heading; /* header string */
input struct hostent *hp; /* location of hostent struct */
{
register char **ap;
printf("%s: %s", heading, hp->h_name);
for (ap = hp->h_addr_list; ap && *ap; ap++)
{
if (ap == hp->h_addr_list)
printf("\nAddress:");
printf(" %s", inet_ntoa(incopy(*ap)));
}
for (ap = hp->h_aliases; ap && *ap && **ap; ap++)
{
if (ap == hp->h_aliases)
printf("\nAliases:");
printf(" %s", *ap);
}
printf("\n\n");
}
/*
** SHOW_RES -- Show resolver database information
** ----------------------------------------------
**
** Returns:
** None.
**
** Inputs:
** The resolver database _res is localized in the resolver.
*/
void
show_res()
{
register int i;
register char **domain;
/*
* The default domain is defined by the "domain" entry in /etc/resolv.conf
* if not overridden by the environment variable "LOCALDOMAIN".
* If still not defined, gethostname() may yield a fully qualified host name.
*/
printf("Default domain:");
if (_res.defdname[0] != '\0')
printf(" %s", _res.defdname);
printf("\n");
/*
* The search domains are extracted from the default domain components,
* but may be overridden by "search" directives in /etc/resolv.conf
* since 4.8.3.
*/
printf("Search domains:");
for (domain = _res.dnsrch; *domain; domain++)
printf(" %s", *domain);
printf("\n");
/*
* The routine res_send() will do _res.retry tries to contact each of the
* _res.nscount nameserver addresses before giving up when using datagrams.
* The first try will timeout after _res.retrans seconds. Each following
* try will timeout after ((_res.retrans << try) / _res.nscount) seconds.
* Note. When we contact an explicit server the addresses will be replaced
* by the multiple addresses of the same server.
* When doing a zone transfer _res.retrans is used for the connect timeout.
*/
printf("Timeout per retry: %d secs\n", _res.retrans);
printf("Number of retries: %d\n", _res.retry);
printf("Number of addresses: %d\n", _res.nscount);
for (i = 0; i < _res.nscount; i++)
printf("%s\n", inet_ntoa(nslist(i).sin_addr));
/*
* The resolver options are initialized by res_init() to contain the
* defaults settings (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH)
* The various options have the following meaning:
*
* RES_INIT set after res_init() has been called
* RES_DEBUG let the resolver modules print debugging info
* RES_AAONLY want authoritative answers only (not implemented)
* RES_USEVC use tcp virtual circuit instead of udp datagrams
* RES_PRIMARY use primary nameserver only (not implemented)
* RES_IGNTC ignore datagram truncation; don't switch to tcp
* RES_RECURSE forward query if answer not locally available
* RES_DEFNAMES add default domain to queryname without dot
* RES_STAYOPEN keep tcp socket open for subsequent queries
* RES_DNSRCH append search domains even to queryname with dot
*/
printf("Options set:");
if (bitset(RES_INIT, _res.options)) printf(" INIT");
if (bitset(RES_DEBUG, _res.options)) printf(" DEBUG");
if (bitset(RES_AAONLY, _res.options)) printf(" AAONLY");
if (bitset(RES_USEVC, _res.options)) printf(" USEVC");
if (bitset(RES_PRIMARY, _res.options)) printf(" PRIMARY");
if (bitset(RES_IGNTC, _res.options)) printf(" IGNTC");
if (bitset(RES_RECURSE, _res.options)) printf(" RECURSE");
if (bitset(RES_DEFNAMES, _res.options)) printf(" DEFNAMES");
if (bitset(RES_STAYOPEN, _res.options)) printf(" STAYOPEN");
if (bitset(RES_DNSRCH, _res.options)) printf(" DNSRCH");
printf("\n");
printf("Options clr:");
if (!bitset(RES_INIT, _res.options)) printf(" INIT");
if (!bitset(RES_DEBUG, _res.options)) printf(" DEBUG");
if (!bitset(RES_AAONLY, _res.options)) printf(" AAONLY");
if (!bitset(RES_USEVC, _res.options)) printf(" USEVC");
if (!bitset(RES_PRIMARY, _res.options)) printf(" PRIMARY");
if (!bitset(RES_IGNTC, _res.options)) printf(" IGNTC");
if (!bitset(RES_RECURSE, _res.options)) printf(" RECURSE");
if (!bitset(RES_DEFNAMES, _res.options)) printf(" DEFNAMES");
if (!bitset(RES_STAYOPEN, _res.options)) printf(" STAYOPEN");
if (!bitset(RES_DNSRCH, _res.options)) printf(" DNSRCH");
printf("\n");
/*
* The new BIND 4.9.3 has additional features which are not (yet) used.
*/
printf("\n");
}
/*
** PRINT_STATISTICS -- Print resource record statistics
** ----------------------------------------------------
**
** Returns:
** None.
**
** Inputs:
** The record_stats[] counts have been updated by print_rrec().
*/
void
print_statistics(name, filter, class)
input char *name; /* name of zone we are listing */
input int filter; /* type of records we want to see */
input int class; /* class of records we want to see */
{
register int type;
int nrecords;
for (type = T_FIRST; type <= T_LAST; type++)
{
nrecords = record_stats[type];
if (nrecords > 0 || ((filter != T_ANY) && want_type(type, filter)))
{
printf("Found %4d %-5s record%-1s", nrecords,
pr_type(type), plural(nrecords));
if (class != C_IN)
printf(" in class %s", pr_class(class));
printf(" within %s\n", name);
}
}
}
/*
** CLEAR_STATISTICS -- Clear resource record statistics
** ----------------------------------------------------
**
** Returns:
** None.
*/
void
clear_statistics()
{
bzero((char *)record_stats, sizeof(record_stats));
}
/*
** SHOW_TYPES -- Show resource record types wanted
** -----------------------------------------------
**
** Returns:
** None.
*/
void
show_types(name, filter, class)
input char *name; /* name we want to query about */
input int filter; /* type of records we want to see */
input int class; /* class of records we want to see */
{
register int type;
if (filter >= T_NONE)
{
printf("Query about %s for record types", name);
if (filter == T_ANY)
printf(" %s", pr_type(T_ANY));
else
for (type = T_FIRST; type <= T_LAST; type++)
if (want_type(type, filter))
printf(" %s", pr_type(type));
if (class != C_IN)
printf(" in class %s", pr_class(class));
printf("\n");
}
}
/*
** NS_ERROR -- Print error message from errno and h_errno
** ------------------------------------------------------
**
** Returns:
** None.
**
** If BIND res_send() fails, it will leave errno in either of the first
** two following states when using datagrams. Note that this depends on
** the proper handling of connected datagram sockets, which is usually
** true if BSD >= 43 (see res_send.c for details; it may need a patch).
** Note. If the 4.8 version succeeds, it may leave errno as EAFNOSUPPORT
** if it has disconnected a previously connected datagram socket, since
** the dummy address used to disconnect does not have a proper family set.
** Always clear errno after getting a reply, or patch res_send().
** Our private version of res_send() will leave also other error statuses.
*/
void
ns_error(name, type, class, host)
input char *name; /* full name we queried about */
input int type; /* record type we queried about */
input int class; /* record class we queried about */
input char *host; /* set if explicit server was used */
{
static char *auth = "Authoritative answer";
/*
* Print the message associated with the network related errno values.
*/
switch (errno)
{
case ECONNREFUSED:
/*
* The contacted host does not have a nameserver running.
* The standard res_send() also returns this if none of
* the intended hosts could be reached via datagrams.
*/
if (host != NULL)
errmsg("Nameserver %s not running", host);
else
errmsg("Nameserver not running");
break;
case ETIMEDOUT:
/*
* The contacted server did not give any reply at all
* within the specified time frame.
*/
if (host != NULL)
errmsg("Nameserver %s not responding", host);
else
errmsg("Nameserver not responding");
break;
case ENETDOWN:
case ENETUNREACH:
case EHOSTDOWN:
case EHOSTUNREACH:
/*
* The host to be contacted or its network can not be reached.
* Our private res_send() also returns this using datagrams.
*/
if (host != NULL)
errmsg("Nameserver %s not reachable", host);
else
errmsg("Nameserver not reachable");
break;
}
/*
* Print the message associated with the particular nameserver error.
*/
switch (h_errno)
{
case HOST_NOT_FOUND:
/*
* The specified name does definitely not exist at all.
* In this case the answer is always authoritative.
* Nameserver status: NXDOMAIN
*/
if (class != C_IN)
errmsg("%s does not exist in class %s (%s)",
name, pr_class(class), auth);
else if (host != NULL)
errmsg("%s does not exist at %s (%s)",
name, host, auth);
else
errmsg("%s does not exist (%s)",
name, auth);
break;
case NO_HOST:
/*
* The specified name does not exist, but the answer
* was not authoritative, so it is still undecided.
* Nameserver status: NXDOMAIN
*/
if (class != C_IN)
errmsg("%s does not exist in class %s, try again",
name, pr_class(class));
else if (host != NULL)
errmsg("%s does not exist at %s, try again",
name, host);
else
errmsg("%s does not exist, try again",
name);
break;
case NO_DATA:
/*
* The name is valid, but the specified type does not exist.
* This status is here returned only in case authoritative.
* Nameserver status: NOERROR
*/
if (class != C_IN)
errmsg("%s has no %s record in class %s (%s)",
name, pr_type(type), pr_class(class), auth);
else if (host != NULL)
errmsg("%s has no %s record at %s (%s)",
name, pr_type(type), host, auth);
else
errmsg("%s has no %s record (%s)",
name, pr_type(type), auth);
break;
case NO_RREC:
/*
* The specified type does not exist, but we don't know whether
* the name is valid or not. The answer was not authoritative.
* Perhaps recursion was off, and no data was cached locally.
* Nameserver status: NOERROR
*/
if (class != C_IN)
errmsg("%s %s record in class %s currently not present",
name, pr_type(type), pr_class(class));
else if (host != NULL)
errmsg("%s %s record currently not present at %s",
name, pr_type(type), host);
else
errmsg("%s %s record currently not present",
name, pr_type(type));
break;
case TRY_AGAIN:
/*
* Some intermediate failure, e.g. connect timeout,
* or some local operating system transient errors.
* General failure to reach any appropriate servers.
* The status SERVFAIL now yields a separate error code.
* Nameserver status: (SERVFAIL)
*/
if (class != C_IN)
errmsg("%s %s record in class %s not found, try again",
name, pr_type(type), pr_class(class));
else if (host != NULL)
errmsg("%s %s record not found at %s, try again",
name, pr_type(type), host);
else
errmsg("%s %s record not found, try again",
name, pr_type(type));
break;
case SERVER_FAILURE:
/*
* Explicit server failure status. This will be returned upon
* some internal server errors, forwarding failures, or when
* the server is not authoritative for a specific class.
* Also if the zone data has expired at a secondary server.
* Nameserver status: SERVFAIL
*/
if (class != C_IN)
errmsg("%s %s record in class %s not found, server failure",
name, pr_type(type), pr_class(class));
else if (host != NULL)
errmsg("%s %s record not found at %s, server failure",
name, pr_type(type), host);
else
errmsg("%s %s record not found, server failure",
name, pr_type(type));
break;
case NO_RECOVERY:
/*
* Some irrecoverable format error, or server refusal.
* The status REFUSED now yields a separate error code.
* Nameserver status: (REFUSED) FORMERR NOTIMP NOCHANGE
*/
if (class != C_IN)
errmsg("%s %s record in class %s not found, no recovery",
name, pr_type(type), pr_class(class));
else if (host != NULL)
errmsg("%s %s record not found at %s, no recovery",
name, pr_type(type), host);
else
errmsg("%s %s record not found, no recovery",
name, pr_type(type));
break;
case QUERY_REFUSED:
/*
* The server explicitly refused to answer the query.
* Servers can be configured to disallow zone transfers.
* Nameserver status: REFUSED
*/
if (class != C_IN)
errmsg("%s %s record in class %s query refused",
name, pr_type(type), pr_class(class));
else if (host != NULL)
errmsg("%s %s record query refused by %s",
name, pr_type(type), host);
else
errmsg("%s %s record query refused",
name, pr_type(type));
break;
default:
/*
* Unknown cause for server failure.
*/
if (class != C_IN)
errmsg("%s %s record in class %s not found",
name, pr_type(type), pr_class(class));
else if (host != NULL)
errmsg("%s %s record not found at %s",
name, pr_type(type), host);
else
errmsg("%s %s record not found",
name, pr_type(type));
break;
}
}
/*
** DECODE_ERROR -- Convert nameserver error code to error message
** --------------------------------------------------------------
**
** Returns:
** Pointer to appropriate error message.
*/
char *
decode_error(rcode)
input int rcode; /* error code from bp->rcode */
{
switch (rcode)
{
case NOERROR: return("no error");
case FORMERR: return("format error");
case SERVFAIL: return("server failure");
case NXDOMAIN: return("non-existent domain");
case NOTIMP: return("not implemented");
case REFUSED: return("query refused");
case NOCHANGE: return("no change");
}
return("unknown error");
}
/*
** PRINT_STATUS -- Print result status after nameserver query
** ----------------------------------------------------------
**
** Returns:
** None.
**
** Conditions:
** The size of the answer buffer must have been
** checked before to be of sufficient length,
** i.e. to contain at least the buffer header.
*/
void
print_status(answerbuf)
input querybuf *answerbuf; /* location of answer buffer */
{
HEADER *bp;
int ancount;
bool failed;
bp = (HEADER *)answerbuf;
ancount = ntohs(bp->ancount);
failed = (bp->rcode != NOERROR || ancount == 0);
printf("%sQuery %s, %d answer%s%s, %sstatus: %s\n",
verbose ? "" : dbprefix,
failed ? "failed" : "done",
ancount, plural(ancount),
bp->tc ? " (truncated)" : "",
bp->aa ? "authoritative " : "",
decode_error((int)bp->rcode));
}
/*
** PR_ERROR -- Print error message about encountered inconsistencies
** -----------------------------------------------------------------
**
** We are supposed to have an error condition which is fatal
** for normal continuation, and the message is always printed.
**
** Returns:
** None.
**
** Side effects:
** Increments the global error count.
*/
void /*VARARGS1*/
pr_error(fmt, a, b, c, d)
input char *fmt; /* format of message */
input char *a, *b, *c, *d; /* optional arguments */
{
(void) fprintf(stderr, " *** ");
(void) fprintf(stderr, fmt, a, b, c, d);
(void) fprintf(stderr, "\n");
/* flag an error */
errorcount++;
}
/*
** PR_WARNING -- Print warning message about encountered inconsistencies
** ---------------------------------------------------------------------
**
** We are supposed to have an error condition which is non-fatal
** for normal continuation, and the message is suppressed in case
** quiet mode has been selected.
**
** Returns:
** None.
*/
void /*VARARGS1*/
pr_warning(fmt, a, b, c, d)
input char *fmt; /* format of message */
input char *a, *b, *c, *d; /* optional arguments */
{
if (!quiet)
{
(void) fprintf(stderr, " !!! ");
(void) fprintf(stderr, fmt, a, b, c, d);
(void) fprintf(stderr, "\n");
}
}
/*
** WANT_TYPE -- Indicate whether the rr type matches the desired filter
** --------------------------------------------------------------------
**
** Returns:
** TRUE if the resource record type matches the filter.
** FALSE otherwise.
**
** In regular mode, the querytype is used to formulate the query,
** and the filter is set to T_ANY to filter out any response.
** In listmode, we get everything, so the filter is set to the
** querytype to filter out the proper responses.
** Note that T_NONE is the default querytype in listmode.
*/
bool
want_type(type, filter)
input int type; /* resource record type */
input int filter; /* type of records we want to see */
{
if (type == filter)
return(TRUE);
if (filter == T_ANY)
return(TRUE);
if (filter == T_NONE &&
(type == T_A || type == T_NS || type == T_PTR))
return(TRUE);
if (filter == T_MAILB &&
(type == T_MB || type == T_MR || type == T_MG || type == T_MINFO))
return(TRUE);
if (filter == T_MAILA &&
(type == T_MD || type == T_MF))
return(TRUE);
return(FALSE);
}
/*
** WANT_CLASS -- Indicate whether the rr class matches the desired filter
** ----------------------------------------------------------------------
**
** Returns:
** TRUE if the resource record class matches the filter.
** FALSE otherwise.
**
** In regular mode, the queryclass is used to formulate the query,
** and the filter is set to C_ANY to filter out any response.
** In listmode, we get everything, so the filter is set to the
** queryclass to filter out the proper responses.
** Note that C_IN is the default queryclass in listmode.
*/
bool
want_class(class, filter)
input int class; /* resource record class */
input int filter; /* class of records we want to see */
{
if (class == filter)
return(TRUE);
if (filter == C_ANY)
return(TRUE);
return(FALSE);
}
/*
** INDOMAIN -- Check whether a name belongs to a zone
** --------------------------------------------------
**
** Returns:
** TRUE if the given name lies anywhere in the zone, or
** if the given name is the same as the zone and may be so.
** FALSE otherwise.
*/
bool
indomain(name, domain, equal)
input char *name; /* the name under consideration */
input char *domain; /* the name of the zone */
input bool equal; /* set if name may be same as zone */
{
register char *dot;
if (sameword(name, domain))
return(equal);
if (sameword(domain, "."))
return(TRUE);
dot = index(name, '.');
while (dot != NULL)
{
if (sameword(dot+1, domain))
return(TRUE);
dot = index(dot+1, '.');
}
return(FALSE);
}
/*
** SAMEDOMAIN -- Check whether a name belongs to a zone
** ----------------------------------------------------
**
** Returns:
** TRUE if the given name lies directly in the zone, or
** if the given name is the same as the zone and may be so.
** FALSE otherwise.
*/
bool
samedomain(name, domain, equal)
input char *name; /* the name under consideration */
input char *domain; /* the name of the zone */
input bool equal; /* set if name may be same as zone */
{
register char *dot;
if (sameword(name, domain))
return(equal);
dot = index(name, '.');
if (dot == NULL)
return(sameword(domain, "."));
if (sameword(dot+1, domain))
return(TRUE);
return(FALSE);
}
/*
** GLUERECORD -- Check whether a name is a glue record
** ---------------------------------------------------
**
** Returns:
** TRUE is this is a glue record.
** FALSE otherwise.
**
** The name is supposed to be the name of an address record.
** If it lies directly in the given zone, it is considered
** an ordinary host within that zone, and not a glue record.
** If it does not belong to the given zone at all, is it
** here considered to be a glue record.
** If it lies in the given zone, but not directly, it is
** considered a glue record if it belongs to any of the known
** delegated zones of the given zone.
** In the root zone itself are no hosts, only glue records.
*/
bool
gluerecord(name, domain, zone, nzones)
input char *name; /* the name under consideration */
input char *domain; /* name of zone being processed */
input char *zone[]; /* list of known delegated zones */
input int nzones; /* number of known delegated zones */
{
register int n;
if (sameword(domain, "."))
return(TRUE);
if (samedomain(name, domain, TRUE))
return(FALSE);
if (!indomain(name, domain, TRUE))
return(TRUE);
for (n = 0; n < nzones; n++)
if (indomain(name, zone[n], TRUE))
return(TRUE);
return(FALSE);
}
/*
** MATCHLABELS -- Determine number of matching domain name labels
** --------------------------------------------------------------
**
** Returns:
** Number of shared trailing components in both names.
*/
int
matchlabels(name, domain)
input char *name; /* domain name to check */
input char *domain; /* domain name to compare against */
{
register int i, j;
int matched = 0;
i = strlength(name);
j = strlength(domain);
while (--i >= 0 && --j >= 0)
{
if (lower(name[i]) != lower(domain[j]))
break;
if (domain[j] == '.')
matched++;
else if (j == 0 && (i == 0 || name[i-1] == '.'))
matched++;
}
return(matched);
}
/*
** PR_DOMAIN -- Convert domain name according to printing options
** --------------------------------------------------------------
**
** Returns:
** Pointer to new domain name, if conversion was done.
** Pointer to original name, if no conversion necessary.
*/
char *
pr_domain(name, listing)
input char *name; /* domain name to be printed */
input bool listing; /* set if this is a zone listing */
{
char *newname; /* converted domain name */
/*
* Print reverse nsap.int name in forward notation, unless prohibited.
*/
if (revnsap && !dotprint)
{
newname = pr_nsap(name);
if (newname != name)
return(newname);
}
/*
* Print domain names with trailing dot if necessary.
*/
if (listing || dotprint)
{
newname = pr_dotname(name);
if (newname != name)
return(newname);
}
/*
* No conversion was required, use original name.
*/
return(name);
}
/*
** PR_DOTNAME -- Return domain name with trailing dot
** --------------------------------------------------
**
** Returns:
** Pointer to new domain name, if dot was added.
** Pointer to original name, if dot was already present.
*/
char *
pr_dotname(name)
input char *name; /* domain name to append to */
{
static char buf[MAXDNAME+2]; /* buffer to store new domain name */
register int n;
n = strlength(name);
if (n > 0 && name[n-1] == '.')
return(name);
if (n > MAXDNAME)
n = MAXDNAME;
#ifdef obsolete
(void) sprintf(buf, "%.*s.", MAXDNAME, name);
#endif
bcopy(name, buf, n);
buf[n] = '.';
buf[n+1] = '\0';
return(buf);
}
/*
** PR_NSAP -- Convert reverse nsap.int to dotted forward notation
** --------------------------------------------------------------
**
** Returns:
** Pointer to new dotted nsap, if converted.
** Pointer to original name otherwise.
*/
char *
pr_nsap(name)
input char *name; /* potential reverse nsap.int name */
{
static char buf[3*MAXNSAP+1];
register char *p;
register int n;
register int i;
/* must begin with single hex digits separated by dots */
for (i = 0; is_xdigit(name[i]) && name[i+1] == '.'; i += 2)
continue;
/* must have an even number of hex digits */
if (i == 0 || (i % 4) != 0)
return(name);
/* but not too many */
if (i > 4*MAXNSAP)
return(name);
/* must end in the appropriate root domain */
if (!sameword(&name[i], NSAP_ROOT))
return(name);
for (p = buf, n = 0; i >= 4; i -= 4, n++)
{
*p++ = name[i-2];
*p++ = name[i-4];
/* add dots for readability */
if ((n % 2) == 0 && (i - 4) > 0)
*p++ = '.';
}
*p = '\0';
return(buf);
}
/*
** PR_TYPE -- Return name of resource record type
** ----------------------------------------------
**
** Returns:
** Pointer to name of resource record type.
**
** Note. All possible (even obsolete) types are recognized.
*/
char *
pr_type(type)
input int type; /* resource record type */
{
static char buf[30];
switch (type)
{
case T_A: return("A"); /* internet address */
case T_NS: return("NS"); /* authoritative server */
case T_MD: return("MD"); /* mail destination */
case T_MF: return("MF"); /* mail forwarder */
case T_CNAME: return("CNAME"); /* canonical name */
case T_SOA: return("SOA"); /* start of auth zone */
case T_MB: return("MB"); /* mailbox domain name */
case T_MG: return("MG"); /* mail group member */
case T_MR: return("MR"); /* mail rename name */
case T_NULL: return("NULL"); /* null resource record */
case T_WKS: return("WKS"); /* well known service */
case T_PTR: return("PTR"); /* domain name pointer */
case T_HINFO: return("HINFO"); /* host information */
case T_MINFO: return("MINFO"); /* mailbox information */
case T_MX: return("MX"); /* mail routing info */
case T_TXT: return("TXT"); /* descriptive text */
case T_RP: return("RP"); /* responsible person */
case T_AFSDB: return("AFSDB"); /* afs database location */
case T_X25: return("X25"); /* x25 address */
case T_ISDN: return("ISDN"); /* isdn address */
case T_RT: return("RT"); /* route through host */
case T_NSAP: return("NSAP"); /* nsap address */
case T_NSAPPTR: return("NSAP-PTR"); /* nsap pointer */
case T_SIG: return("SIG"); /* security signature */
case T_KEY: return("KEY"); /* security key */
case T_PX: return("PX"); /* rfc822 - x400 mapping */
case T_GPOS: return("GPOS"); /* geographical position */
case T_AAAA: return("AAAA"); /* ip v6 address */
case T_LOC: return("LOC"); /* geographical location */
case T_UINFO: return("UINFO"); /* user information */
case T_UID: return("UID"); /* user ident */
case T_GID: return("GID"); /* group ident */
case T_UNSPEC: return("UNSPEC"); /* unspecified binary data */
case T_AXFR: return("AXFR"); /* zone transfer */
case T_MAILB: return("MAILB"); /* matches MB/MR/MG/MINFO */
case T_MAILA: return("MAILA"); /* matches MD/MF */
case T_ANY: return("ANY"); /* matches any type */
case T_NONE: return("resource"); /* not yet determined */
}
(void) sprintf(buf, "%d", type);
return(buf);
}
/*
** PR_CLASS -- Return name of resource record class
** ------------------------------------------------
**
** Returns:
** Pointer to name of resource record class.
*/
char *
pr_class(class)
input int class; /* resource record class */
{
static char buf[30];
switch (class)
{
case C_IN: return("IN"); /* internet */
case C_CSNET: return("CS"); /* csnet */
case C_CHAOS: return("CH"); /* chaosnet */
case C_HS: return("HS"); /* hesiod */
case C_ANY: return("ANY"); /* any class */
}
(void) sprintf(buf, "%d", class);
return(buf);
}
/*
** EXPAND_NAME -- Expand compressed domain name in a recource record
** -----------------------------------------------------------------
**
** Returns:
** Number of bytes advanced in answer buffer.
** -1 if there was a format error.
**
** It is assumed that the specified buffer is of sufficient size.
*/
int
expand_name(name, type, cp, msg, eom, namebuf)
input char *name; /* name of resource record */
input int type; /* type of resource record */
input u_char *cp; /* current position in answer buf */
input u_char *msg, *eom; /* begin and end of answer buf */
output char *namebuf; /* location of buf to expand name in */
{
register int n;
n = dn_expand(msg, eom, cp, (nbuf_t *)namebuf, MAXDNAME);
if (n < 0)
{
pr_error("expand error in %s record for %s, offset %s",
pr_type(type), name, itoa(cp - msg));
h_errno = NO_RECOVERY;
return(-1);
}
/* change root to single dot */
if (namebuf[0] == '\0')
{
namebuf[0] = '.';
namebuf[1] = '\0';
}
return(n);
}
/*
** CHECK_SIZE -- Check whether resource record is of sufficient length
** -------------------------------------------------------------------
**
** Returns:
** Requested size if current record is long enough.
** -1 if current record does not have this many bytes.
**
** Note that HINFO records are very often incomplete since only
** one of the two data fields has been filled in and the second
** field is missing. So we generate only a warning message.
*/
int
check_size(name, type, cp, msg, eor, size)
input char *name; /* name of resource record */
input int type; /* type of resource record */
input u_char *cp; /* current position in answer buf */
input u_char *msg; /* begin of answer buf */
input u_char *eor; /* predicted position of next record */
input int size; /* required record size remaining */
{
if (cp + size > eor)
{
if (type != T_HINFO)
pr_error("incomplete %s record for %s, offset %s",
pr_type(type), name, itoa(cp - msg));
else
pr_warning("incomplete %s record for %s",
pr_type(type), name);
h_errno = NO_RECOVERY;
return(-1);
}
return(size);
}
/*
** VALID_NAME -- Check whether domain name contains invalid characters
** -------------------------------------------------------------------
**
** Returns:
** TRUE if the name is valid.
** FALSE otherwise.
**
** The total size of a compound name should not exceed MAXDNAME.
** We assume that this is true. Its individual components between
** dots should not be longer than 64. This is not checked here.
**
** Only alphanumeric characters and dash '-' may be used (dash
** only in the middle). We only check the individual characters.
** Strictly speaking, this restriction is only for ``host names''.
** The underscore is illegal, at least not recommended, but is
** so abundant that is requires special processing.
**
** If the domain name represents a mailbox specification, the
** first label up to the first (unquoted) dot is the local part
** of a mail address, which should adhere to the RFC 822 specs.
** This first dot takes the place of the RFC 822 '@' sign.
**
** The label '*' can in principle be used anywhere to indicate
** wildcarding. It is valid only in the LHS resource record name,
** in definitions in zone files only as the first component.
** Used primarily in wildcard MX record definitions.
*/
char *specials = ".()<>@,;:\\\"[]"; /* RFC 822 specials */
bool
valid_name(name, wildcard, localpart, underscore)
input char *name; /* domain name to check */
input bool wildcard; /* set if wildcard is allowed */
input bool localpart; /* set if this is a mailbox spec */
input bool underscore; /* set if underscores are allowed */
{
bool backslash = FALSE;
bool quoting = FALSE;
register char *p;
register char c;
for (p = name; (c = *p) != '\0'; p++)
{
/* special check for local part in mailbox */
if (localpart)
{
if (backslash)
backslash = FALSE; /* escape this char */
else if (c == '\\')
backslash = TRUE; /* escape next char */
else if (c == '"')
quoting = !quoting; /* start/stop quoting */
else if (quoting)
continue; /* allow quoted chars */
else if (c == '.')
localpart = FALSE; /* instead of '@' */
else if (c == '@')
return(FALSE); /* should be '.' */
else if (in_string(specials, c))
return(FALSE); /* must be escaped */
else if (is_space(c))
return(FALSE); /* must be escaped */
continue;
}
/* basic character set */
if (is_alnum(c) || (c == '-'))
continue;
/* start of a new component */
if (c == '.')
continue;
/* allow '*' for use in wildcard names */
if ((c == '*') && wildcard)
continue;
/* ignore underscore in certain circumstances */
if ((c == '_') && underscore && !illegal)
continue;
/* silently allowed widespread exceptions */
if (illegal && in_string(illegal, c))
continue;
return(FALSE);
}
/* must be beyond the local part in a mailbox */
if (localpart)
return(FALSE);
return(TRUE);
}
/*
** CANONICAL -- Check whether domain name is a canonical host name
** ---------------------------------------------------------------
**
** Returns:
** Nonzero if the name is definitely not canonical.
** 0 if it is canonical, or if it remains undecided.
*/
int
canonical(name)
input char *name; /* the domain name to check */
{
struct hostent *hp;
int status;
int save_errno;
int save_herrno;
/*
* Preserve state when querying, to avoid clobbering current values.
*/
save_errno = errno;
save_herrno = h_errno;
hp = gethostbyname(name);
status = h_errno;
errno = save_errno;
h_errno = save_herrno;
/*
* Indicate negative result only after definitive lookup failures.
*/
if (hp == NULL)
{
/* authoritative denial -- not existing or no A record */
if (status == NO_DATA || status == HOST_NOT_FOUND)
return(status);
/* nameserver failure -- still undecided, assume ok */
return(0);
}
/*
* The given name exists and there is an associated A record.
* The name of this A record should be the name we queried about.
* If this is not the case we probably supplied a CNAME.
*/
status = sameword(hp->h_name, name) ? 0 : HOST_NOT_CANON;
return(status);
}
/*
** MAPREVERSE -- Check whether address maps back to given domain
** -------------------------------------------------------------
**
** Returns:
** NULL if address could definitively not be mapped.
** Given name if the address maps back properly, or
** in case of transient nameserver failures.
** Reverse name if it differs from the given name.
*/
char *
mapreverse(name, inaddr)
input char *name; /* domain name of A record */
input struct in_addr inaddr; /* address of A record to check */
{
struct hostent *hp;
int status;
int save_errno;
int save_herrno;
/*
* Preserve state when querying, to avoid clobbering current values.
*/
save_errno = errno;
save_herrno = h_errno;
hp = gethostbyaddr((char *)&inaddr, INADDRSZ, AF_INET);
status = h_errno;
errno = save_errno;
h_errno = save_herrno;
/*
* Indicate negative result only after definitive lookup failures.
*/
if (hp == NULL)
{
/* authoritative denial -- not existing or no PTR record */
if (status == NO_DATA || status == HOST_NOT_FOUND)
return(NULL);
/* nameserver failure -- still undecided, assume ok */
return(name);
}
/*
* Indicate whether the reverse mapping yields the given name.
*/
return(sameword(hp->h_name, name) ? name : hp->h_name);
}
/*
** COMPARE_NAME -- Compare two names wrt alphabetical order
** --------------------------------------------------------
**
** Returns:
** Value of case-insensitive comparison.
*/
int
compare_name(a, b)
input char **a; /* first name */
input char **b; /* second name */
{
return(strcasecmp(*a, *b));
}
/*
** XALLOC -- Allocate or reallocate additional memory
** --------------------------------------------------
**
** Returns:
** Pointer to (re)allocated buffer space.
** Aborts if the requested memory could not be obtained.
*/
ptr_t *
xalloc(buf, size)
register ptr_t *buf; /* current start of buffer space */
input siz_t size; /* number of bytes to allocate */
{
if (buf == NULL)
buf = malloc(size);
else
buf = realloc(buf, size);
if (buf == NULL)
{
errmsg("Out of memory");
exit(EX_OSERR);
}
return(buf);
}
/*
** ITOA -- Convert integer value to ascii string
** ---------------------------------------------
**
** Returns:
** Pointer to string.
*/
char *
itoa(n)
input int n; /* value to convert */
{
static char buf[30];
(void) sprintf(buf, "%d", n);
return(buf);
}
/*
** UTOA -- Convert unsigned integer value to ascii string
** ------------------------------------------------------
**
** Returns:
** Pointer to string.
*/
char *
utoa(n)
input int n; /* value to convert */
{
static char buf[30];
(void) sprintf(buf, "%u", (unsigned)n);
return(buf);
}
/*
** STOA -- Extract partial ascii string
** ------------------------------------
**
** Returns:
** Pointer to string.
*/
char *
stoa(cp, size)
input u_char *cp; /* current position in answer buf */
input int size; /* number of bytes to extract */
{
static char buf[MAXDLEN+1];
if (size > MAXDLEN)
size = MAXDLEN;
#ifdef obsolete
if (size > 0)
(void) sprintf(buf, "%.*s", size, (char *)cp);
else
(void) sprintf(buf, "%s", "");
#endif
bcopy((char *)cp, buf, size);
buf[size] = '\0';
return(buf);
}
/*
** NSAP_NTOA -- Convert binary nsap address to ascii
** -------------------------------------------------
**
** Returns:
** Pointer to string.
**
** As per RFC 1637 an nsap address is encoded in binary form
** in the resource record. It was unclear from RFC 1348 how
** the encoding should be. RFC 1629 defines an upper bound
** of 20 bytes to the size of a binary nsap address.
*/
char *
nsap_ntoa(cp, size)
input u_char *cp; /* current position in answer buf */
input int size; /* number of bytes to extract */
{
static char buf[3*MAXNSAP+1];
register char *p;
register int n;
register int i;
if (size > MAXNSAP)
size = MAXNSAP;
for (p = buf, i = 0; i < size; i++, cp++)
{
n = ((int)(*cp) >> 4) & 0x0f;
*p++ = hexdigit(n);
n = ((int)(*cp) >> 0) & 0x0f;
*p++ = hexdigit(n);
/* add dots for readability */
if ((i % 2) == 0 && (i + 1) < size)
*p++ = '.';
}
*p = '\0';
return(buf);
}
/*
** PR_TIME -- Produce printable version of a time interval
** -------------------------------------------------------
**
** Returns:
** Pointer to a string version of interval.
**
** The value is a time interval expressed in seconds.
*/
char *
pr_time(value, brief)
input int value; /* the interval to be converted */
input bool brief; /* use brief format if set */
{
static char buf[256];
register char *p = buf;
int week, days, hour, mins, secs;
/* special cases */
if (value < 0)
return("negative");
if ((value == 0) && !brief)
return("zero seconds");
/*
* Decode the components.
*/
secs = value % 60; value /= 60;
mins = value % 60; value /= 60;
hour = value % 24; value /= 24;
days = value;
if (!brief)
{
days = value % 7; value /= 7;
week = value;
}
/*
* Now turn it into a sexy form.
*/
if (brief)
{
if (days > 0)
{
(void) sprintf(p, "%d+", days);
p += strlength(p);
}
(void) sprintf(p, "%02d:%02d:%02d", hour, mins, secs);
return(buf);
}
if (week > 0)
{
(void) sprintf(p, ", %d week%s", week, plural(week));
p += strlength(p);
}
if (days > 0)
{
(void) sprintf(p, ", %d day%s", days, plural(days));
p += strlength(p);
}
if (hour > 0)
{
(void) sprintf(p, ", %d hour%s", hour, plural(hour));
p += strlength(p);
}
if (mins > 0)
{
(void) sprintf(p, ", %d minute%s", mins, plural(mins));
p += strlength(p);
}
if (secs > 0)
{
(void) sprintf(p, ", %d second%s", secs, plural(secs));
/* p += strlength(p); */
}
return(buf + 2);
}
/*
** PR_SPHERICAL -- Produce printable version of a spherical location
** -----------------------------------------------------------------
**
** Returns:
** Pointer to a string version of location.
**
** The value is a spherical location (latitude or longitude)
** expressed in thousandths of a second of arc.
** The value 2^31 represents zero (equator or prime meridian).
*/
char *
pr_spherical(value, pos, neg)
input int value; /* the location to be converted */
input char *pos; /* suffix if value positive */
input char *neg; /* suffix if value negative */
{
static char buf[256];
register char *p = buf;
char *direction;
int degrees, minutes, seconds, fracsec;
/*
* Normalize.
*/
value -= (1 << 31);
direction = pos;
if (value < 0)
{
direction = neg;
value = -value;
}
/*
* Decode the components.
*/
fracsec = value % 1000; value /= 1000;
seconds = value % 60; value /= 60;
minutes = value % 60; value /= 60;
degrees = value;
/*
* Construct output string.
*/
(void) sprintf(p, "%d", degrees);
p += strlength(p);
if (minutes > 0 || seconds > 0 || fracsec > 0)
{
(void) sprintf(p, " %02d", minutes);
p += strlength(p);
}
if (seconds > 0 || fracsec > 0)
{
(void) sprintf(p, " %02d", seconds);
p += strlength(p);
}
if (fracsec > 0)
{
(void) sprintf(p, ".%03d", fracsec);
p += strlength(p);
}
(void) sprintf(p, " %s", direction);
#ifdef obsolete
(void) sprintf(buf, "%d %02d %02d.%03d %s",
degrees, minutes, seconds, fracsec, direction);
#endif
return(buf);
}
/*
** PR_VERTICAL -- Produce printable version of a vertical location
** ---------------------------------------------------------------
**
** Returns:
** Pointer to a string version of location.
**
** The value is an altitude expressed in centimeters, starting
** from a base 100000 meters below the GPS reference spheroid.
** This allows for the actual range [-10000000 .. 4293967296].
*/
char *
pr_vertical(value, pos, neg)
input int value; /* the location to be converted */
input char *pos; /* prefix if value positive */
input char *neg; /* prefix if value negative */
{
static char buf[256];
register char *p = buf;
char *direction;
int meters, centimeters;
unsigned int altitude;
unsigned int reference;
/*
* Normalize.
*/
altitude = value;
reference = 100000*100;
if (altitude < reference)
{
direction = neg;
altitude = reference - altitude;
}
else
{
direction = pos;
altitude = altitude - reference;
}
/*
* Decode the components.
*/
centimeters = altitude % 100; altitude /= 100;
meters = altitude;
/*
* Construct output string.
*/
(void) sprintf(p, "%s%d", direction, meters);
p += strlength(p);
if (centimeters > 0)
(void) sprintf(p, ".%02d", centimeters);
#ifdef obsolete
(void) sprintf(buf, "%s%d.%02d", direction, meters, centimeters);
#endif
return(buf);
}
/*
** PR_PRECISION -- Produce printable version of a location precision
** -----------------------------------------------------------------
**
** Returns:
** Pointer to a string version of precision.
**
** The value is a precision expressed in centimeters, encoded
** as 4-bit mantissa and 4-bit power of 10 (each ranging 0-9).
*/
unsigned int poweroften[10] =
{1,10,100,1000,10000,100000,1000000,10000000,100000000,1000000000};
char *
pr_precision(value)
input int value; /* the precision to be converted */
{
static char buf[256];
register char *p = buf;
int meters, centimeters;
unsigned int precision;
register int mantissa;
register int exponent;
/*
* Normalize.
*/
mantissa = ((value >> 4) & 0x0f) % 10;
exponent = ((value >> 0) & 0x0f) % 10;
precision = mantissa * poweroften[exponent];
/*
* Decode the components.
*/
centimeters = precision % 100; precision /= 100;
meters = precision;
/*
* Construct output string.
*/
(void) sprintf(p, "%d", meters);
p += strlength(p);
if (centimeters > 0)
(void) sprintf(p, ".%02d", centimeters);
#ifdef obsolete
(void) sprintf(buf, "%d.%02d", meters, centimeters);
#endif
return(buf);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.