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/*
* Miscellaneous routines to support the xmodem file transfer protocols.
*/
#define TMP_FILE "trunXXXXXX"
#include <stdio.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "config.h"
#include "misc.h"
#include "param.h"
#include "xmodem.h"
#ifdef BSD
#include <setjmp.h>
jmp_buf gl_buf, rl_buf;
#endif /* BSD */
/*
* Calculate the CRC for the given buffer
*/
unsigned short
calc_crc(buf, len)
unsigned char *buf;
int len;
{
register int i;
unsigned short crc;
static unsigned short crctab[256] = {
0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0};
crc = 0;
for (i=0; i<len; i++)
crc = (crc<<8) ^ crctab[(crc>>8) ^ *buf++];
return(crc);
}
/*
* Calculate the checksum for the given buffer.
*/
unsigned char
calc_sum(buf, len)
unsigned char *buf;
int len;
{
unsigned char sum;
sum = 0;
while (--len >= 0)
sum += *buf++;
return(sum);
}
/*
* Get a single character from the line with a specified time-out period
* in seconds. If the function times-out, it returns a -1.
*/
static int gl_flag;
int
getc_line(sec)
unsigned int sec;
{
extern int fd;
static int gl_force();
char c;
unsigned int alarm();
signal(SIGALRM, (SIG_TYPE(*) ()) gl_force);
gl_flag = 0;
alarm(sec);
#ifdef BSD
if (setjmp(gl_buf))
return(-1);
#endif /* BSD */
if (read(fd, &c, 1) <= 0) {
alarm(0);
return(-1);
}
if (gl_flag)
return(-1);
alarm(0);
return(c & 0xff);
}
/* ARGSUSED */
static int
gl_force(dummy)
int dummy;
{
#ifdef BSD
longjmp(gl_buf, 1);
#else /* BSD */
signal(SIGALRM, (SIG_TYPE(*) ()) gl_force);
gl_flag = 1;
#endif /* BSD */
}
/*
* Same as above, but reads a bunch of characters. The return code is
* now just a success/fail indicator.
*/
static int rl_flag;
int
fread_line(buf, len, sec)
unsigned char *buf;
unsigned int len, sec;
{
extern int fd;
int n;
static int rl_force();
unsigned int try, alarm();
signal(SIGALRM, (SIG_TYPE(*) ()) rl_force);
rl_flag = 0;
alarm(sec);
while (len) {
/* read at most CLIST_SIZ chars */
try = (len > CLIST_SIZ) ? CLIST_SIZ : len;
#ifdef BSD
if (setjmp(rl_buf))
return(-1);
#endif /* BSD */
if ((n = read(fd, (char *) buf, try)) <= 0) {
alarm(0);
return(-1);
}
if (rl_flag)
return(-1);
len -= n;
buf = buf + n;
}
alarm(0);
return(0);
}
/* ARGSUSED */
static int
rl_force(dummy)
int dummy;
{
#ifdef BSD
longjmp(rl_buf, 1);
#else /* BSD */
signal(SIGALRM, (SIG_TYPE(*) ()) rl_force);
rl_flag = 1;
#endif /* BSD */
}
/*
* Put a character on the TTY line. This serves no useful purpose other
* than making the code look pretty.
*/
int
putc_line(c)
unsigned char c;
{
extern int fd;
return(write(fd, (char *) &c, 1));
}
/*
* Cancel the file transfer. Send several ^X's to the remote, followed
* by an equal number of backspaces (in case they have already aborted and
* we're really at the command line).
*/
void
cancel_xfer(up)
int up;
{
extern char file_name[15];
if (!up && !strcmp(param->abort, "DELETE"))
unlink(file_name);
putc_line(CAN);
putc_line(CAN);
putc_line(CAN);
putc_line(BS);
putc_line(BS);
putc_line(BS);
return;
}
/*
* Shorten a file to a predetermined length. Used to remove the ^Z
* padding from the end of files. (Heaven help us, if one day a binary
* file actually has ^Z's as part of the end of the file).
*/
int
fix_length(file, len)
char *file;
long len;
{
FILE *fp, *tempfp, *my_fopen();
register int num;
static int uid_link(), uid_unlink();
char *mktemp(), tempfile[128], buf[BUFSIZ], *strcpy();
char *s, *strrchr(), *strcat();
struct stat stbuf;
if (stat(file, &stbuf) < 0)
return(1);
/* see if we have any work to do */
if (len >= stbuf.st_size)
return(0);
if (!(fp = my_fopen(file, "r")))
return(1);
/*
* The temporary file should be in the same directory as the
* file being received because otherwise we'd have no way of
* guaranteeing they would be in the same file system. (Hard
* links across different file systems aren't allowed).
*/
strcpy(tempfile, file);
if (s = strrchr(tempfile, '/'))
*++s = '\0';
else
strcpy(tempfile, "./");
strcat(tempfile, TMP_FILE);
mktemp(tempfile);
if (!(tempfp = my_fopen(tempfile, "w"))) {
fclose(fp);
return(1);
}
while (len != 0L) {
num = (len > BUFSIZ) ? BUFSIZ : len;
fread(buf, sizeof(char), num, fp);
if (fwrite(buf, sizeof(char), num, tempfp) != num) {
fclose(fp);
fclose(tempfp);
return(1);
}
len = len - (unsigned int) num;
}
fclose(fp);
fclose(tempfp);
if (uid_unlink(file) < 0)
return(1);
if (uid_link(tempfile, file) < 0)
return(1);
if (uid_unlink(tempfile) < 0)
return(1);
return(0);
}
static int
uid_link(path1, path2)
char *path1, *path2;
{
int ret, status, euid, egid;
void _exit();
#ifdef SETUGID
#ifdef SETUID_BROKE
switch(fork()) {
case 0:
setuid(getuid());
setgid(getgid());
_exit(link(path1, path2));
case -1:
fprintf(stderr, "uid_link: Can't fork\n");
return(-1);
default:
if (wait(&status) == -1) {
fprintf(stderr, "uid_link: wait failed\n");
return(-1);
}
ret = status >> 8;
}
#else /* SETUID_BROKE */
euid = geteuid();
egid = getegid();
setuid(getuid());
setgid(getgid());
ret = link(path1, path2);
setuid(euid);
setgid(egid);
#endif /* SETUID_BROKE */
return(ret);
#else /* SETUGID */
return(link(path1, path2));
#endif /* SETUGID */
}
static int
uid_unlink(path)
char *path;
{
int ret, status, euid, egid;
void _exit();
#ifdef SETUGID
#ifdef SETUID_BROKE
switch(fork()) {
case 0:
setuid(getuid());
setgid(getgid());
_exit(unlink(path));
case -1:
fprintf(stderr, "uid_unlink: Can't fork\n");
return(-1);
default:
if (wait(&status) == -1) {
fprintf(stderr, "uid_unlink: wait failed\n");
return(-1);
}
ret = status >> 8;
}
#else /* SETUID_BROKE */
euid = geteuid();
egid = getegid();
setuid(getuid());
setgid(getgid());
ret = unlink(path);
setuid(euid);
setgid(egid);
#endif /* SETUID_BROKE */
return(ret);
#else /* SETUGID */
return(unlink(path));
#endif /* SETUGID */
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.