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#ifndef lint
static char * rcsid = "$Header: get_tcp_conn.c,v 1.3 91/02/10 13:47:16 sob Exp $";
#endif
#define USE_KEEPALIVES /* XXX should be in ../common/conf.h */
/*
** Routines to open a TCP connection
**
** New version that supports the old (pre 4.2 BSD) socket calls,
** and systems with the old (pre 4.2 BSD) hostname lookup stuff.
** Compile-time options are:
**
** USG - you're on System III/V (you have my sympathies)
** NONETDB - old hostname lookup with rhost()
** OLDSOCKET - different args for socket() and connect()
**
** Erik E. Fair <fair@ucbarpa.berkeley.edu>
**
*/
#include "../common/conf.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <ctype.h>
#include <stdio.h>
#include "get_tcp_conn.h"
#ifndef NONETDB
#include <netdb.h>
#endif NONETDB
extern int errno;
extern char *Pname;
extern char *errmsg();
#ifndef htons
extern u_short htons();
#endif htons
#ifndef NONETDB
extern char *inet_ntoa();
extern u_long inet_addr();
#else
/*
* inet_addr for EXCELAN (which does not have it!)
*
*/
u_long
inet_addr(cp)
register char *cp;
{
u_long val, base, n;
register char c;
u_long octet[4], *octetptr = octet;
#ifndef htonl
extern u_long htonl();
#endif htonl
again:
/*
* Collect number up to ``.''.
* Values are specified as for C:
* 0x=hex, 0=octal, other=decimal.
*/
val = 0; base = 10;
if (*cp == '0')
base = 8, cp++;
if (*cp == 'x' || *cp == 'X')
base = 16, cp++;
while (c = *cp) {
if (isdigit(c)) {
val = (val * base) + (c - '0');
cp++;
continue;
}
if (base == 16 && isxdigit(c)) {
val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
cp++;
continue;
}
break;
}
if (*cp == '.') {
/*
* Internet format:
* a.b.c.d
* a.b.c (with c treated as 16-bits)
* a.b (with b treated as 24 bits)
*/
if (octetptr >= octet + 4)
return (-1);
*octetptr++ = val, cp++;
goto again;
}
/*
* Check for trailing characters.
*/
if (*cp && !isspace(*cp))
return (-1);
*octetptr++ = val;
/*
* Concoct the address according to
* the number of octet specified.
*/
n = octetptr - octet;
switch (n) {
case 1: /* a -- 32 bits */
val = octet[0];
break;
case 2: /* a.b -- 8.24 bits */
val = (octet[0] << 24) | (octet[1] & 0xffffff);
break;
case 3: /* a.b.c -- 8.8.16 bits */
val = (octet[0] << 24) | ((octet[1] & 0xff) << 16) |
(octet[2] & 0xffff);
break;
case 4: /* a.b.c.d -- 8.8.8.8 bits */
val = (octet[0] << 24) | ((octet[1] & 0xff) << 16) |
((octet[2] & 0xff) << 8) | (octet[3] & 0xff);
break;
default:
return (-1);
}
val = htonl(val);
return (val);
}
char *
inet_ntoa(in)
struct in_addr in;
{
static char address[20];
sprintf(address, "%u.%u.%u.%u",
(in.s_addr>>24)&0xff,
(in.s_addr>>16)&0xff,
(in.s_addr>>8 )&0xff,
(in.s_addr )&0xff);
return(address);
}
#endif NONETDB
#ifdef USG
void
bcopy(s, d, l)
register caddr_t s, d;
register int l;
{
while (l-- > 0) *d++ = *s++;
}
#endif USG
/*
** Take the name of an internet host in ASCII (this may either be its
** official host name or internet number (with or without enclosing
** backets [])), and return a list of internet addresses.
**
** returns NULL for failure to find the host name in the local database,
** or for a bad internet address spec.
*/
u_long **
name_to_address(host)
char *host;
{
static u_long *host_addresses[2];
static u_long haddr;
if (host == (char *)NULL) {
return((u_long **)NULL);
}
host_addresses[0] = &haddr;
host_addresses[1] = (u_long *)NULL;
/*
** Is this an ASCII internet address? (either of [10.0.0.78] or
** 10.0.0.78). We get away with the second test because hostnames
** and domain labels are not allowed to begin in numbers.
** (cf. RFC952, RFC882).
*/
if (*host == '[' || isdigit(*host)) {
char namebuf[128];
register char *cp = namebuf;
/*
** strip brackets [] or anything else we don't want.
*/
while(*host != '\0' && cp < &namebuf[sizeof(namebuf)]) {
if (isdigit(*host) || *host == '.')
*cp++ = *host++; /* copy */
else
host++; /* skip */
}
*cp = '\0';
haddr = inet_addr(namebuf);
return(&host_addresses[0]);
} else {
#ifdef NONETDB
extern u_long rhost();
/* lint is gonna bitch about this (comparing an unsigned?!) */
if ((haddr = rhost(&host)) == FAIL)
return((u_long **)NULL); /* no such host */
return(&host_addresses[0]);
#else
struct hostent *hstp = gethostbyname(host);
if (hstp == NULL) {
return((u_long **)NULL); /* no such host */
}
if (hstp->h_length != sizeof(u_long))
abort(); /* this is fundamental */
#ifndef h_addr
/* alignment problems (isn't dbm wonderful?) */
bcopy((caddr_t)hstp->h_addr, (caddr_t)&haddr, sizeof(haddr));
return(&host_addresses[0]);
#else
return((u_long **)hstp->h_addr_list);
#endif h_addr
#endif NONETDB
}
}
/*
** Get a service port number from a service name (or ASCII number)
**
** Return zero if something is wrong (that's a reserved port)
*/
#ifdef NONETDB
static struct Services {
char *name;
u_short port;
} Services[] = {
{"nntp", IPPORT_NNTP}, /* RFC977 */
{"smtp", IPPORT_SMTP}, /* RFC821 */
{"name", IPPORT_NAMESERVER}, /* RFC881, RFC882, RFC883 */
{"time", IPPORT_TIMESERVER}, /* RFC868 */
{"echo", IPPORT_ECHO}, /* RFC862 */
{"discard", IPPORT_DISCARD}, /* RFC863 */
{"daytime", IPPORT_DAYTIME}, /* RFC867 */
{"login", IPPORT_LOGINSERVER}, /* N/A - 4BSD specific */
};
#endif NONETDB
u_short
gservice(serv, proto)
char *serv, *proto;
{
if (serv == (char *)NULL || proto == (char *)NULL)
return((u_short)0);
if (isdigit(*serv)) {
return(htons((u_short)(atoi(serv))));
} else {
#ifdef NONETDB
register int i;
for(i = 0; i < (sizeof(Services) / sizeof(struct Services)); i++) {
if (strcmp(serv, Services[i].name) == 0)
return(htons(Services[i].port));
}
return((u_short)0);
#else
struct servent *srvp = getservbyname(serv, proto);
if (srvp == (struct servent *)NULL)
return((u_short)0);
return((u_short)srvp->s_port);
#endif NONETDB
}
}
/*
** given a host name (either name or internet address) and service name
** (or port number) (both in ASCII), give us a TCP connection to the
** requested service at the requested host (or give us FAIL).
*/
get_tcp_conn(host, serv)
char *host, *serv;
{
register int sock;
u_long **addrlist;
struct sockaddr_in sadr;
#ifdef OLDSOCKET
struct sockproto sp;
sp.sp_family = (u_short)AF_INET;
sp.sp_protocol = (u_short)IPPROTO_TCP;
#endif OLDSOCKET
if ((addrlist = name_to_address(host)) == (u_long **)NULL) {
return(NOHOST);
}
sadr.sin_family = (u_short)AF_INET; /* Only internet for now */
if ((sadr.sin_port = gservice(serv, "tcp")) == 0)
return(NOSERVICE);
for(; *addrlist != (u_long *)NULL; addrlist++) {
bcopy((caddr_t)*addrlist, (caddr_t)&sadr.sin_addr,
sizeof(sadr.sin_addr));
#ifdef OLDSOCKET
if ((sock = socket(SOCK_STREAM, &sp, (struct sockaddr *)NULL, 0)) < 0)
return(FAIL);
if (connect(sock, (struct sockaddr *)&sadr) < 0) {
#else
if ((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
return(FAIL);
if (connect(sock, (struct sockaddr *)&sadr, sizeof(sadr)) < 0) {
#endif OLDSOCKET
int e_save = errno;
fprintf(stderr, "%s: %s [%s]: %s\n", Pname, host,
inet_ntoa(sadr.sin_addr), errmsg(errno));
(void) close(sock); /* dump descriptor */
errno = e_save;
} else
{
#ifdef USE_KEEPALIVES
int on = 1;
if (setsockopt(sock,SOL_SOCKET,SO_KEEPALIVE,(char *)&on,sizeof(on)) < 0)
{ int e_save;
e_save = errno;
fprintf(stderr,"%s: %s [%s]: setsockopt KEEPALIVE: %s\n",Pname,host,inet_ntoa(sadr.sin_addr),errmsg(errno));
/* don't bother erroring out, just note it and ignore it */
}
#endif
return(sock);
}
}
return(FAIL);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.