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/*
* Copyright (c) 1988, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software written by Ken Arnold and
* published in UNIX Review, Vol. 6, No. 8.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. 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 BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)popen.c 8.3 (Berkeley) 4/6/94";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <errno.h>
#include <glob.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "extern.h"
#include "pathnames.h"
#include <syslog.h>
#include <time.h>
#define MAXUSRARGS 100
#define MAXGLOBARGS 1000
/*
* Special version of popen which avoids call to shell. This ensures no one
* may create a pipe to a hidden program as a side effect of a list or dir
* command.
*/
static int *pids;
static int fds;
FILE *
ftpd_popen(char *program, char *type)
{
char *cp;
FILE *iop;
int argc, gargc, pdes[2], pid;
char **pop, *argv[MAXUSRARGS], *gargv[MAXGLOBARGS];
if (((*type != 'r') && (*type != 'w')) || type[1])
return (NULL);
if (!pids) {
if ((fds = getdtablesize()) <= 0)
return (NULL);
if ((pids = calloc(fds, sizeof(int))) == NULL)
return (NULL);
}
if (pipe(pdes) < 0)
return (NULL);
/* break up string into pieces */
for (argc = 0, cp = program; argc < MAXUSRARGS; cp = NULL) {
if (!(argv[argc++] = strtok(cp, " \t\n")))
break;
}
argv[argc - 1] = NULL;
/* glob each piece */
gargv[0] = argv[0];
for (gargc = argc = 1; argv[argc] && gargc < (MAXGLOBARGS-1); argc++) {
glob_t gl;
int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
memset(&gl, 0, sizeof(gl));
gl.gl_matchc = MAXGLOBARGS;
flags |= GLOB_LIMIT;
if (glob(argv[argc], flags, NULL, &gl))
gargv[gargc++] = strdup(argv[argc]);
else if (gl.gl_pathc > 0) {
for (pop = gl.gl_pathv; *pop && gargc < (MAXGLOBARGS-1);
pop++)
gargv[gargc++] = strdup(*pop);
}
globfree(&gl);
}
gargv[gargc] = NULL;
iop = NULL;
fflush(NULL);
pid = (strcmp(gargv[0], _PATH_LS) == 0) ? fork() : vfork();
switch(pid) {
case -1: /* error */
(void)close(pdes[0]);
(void)close(pdes[1]);
goto pfree;
/* NOTREACHED */
case 0: /* child */
if (*type == 'r') {
if (pdes[1] != STDOUT_FILENO) {
dup2(pdes[1], STDOUT_FILENO);
(void)close(pdes[1]);
}
dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */
(void)close(pdes[0]);
} else {
if (pdes[0] != STDIN_FILENO) {
dup2(pdes[0], STDIN_FILENO);
(void)close(pdes[0]);
}
(void)close(pdes[1]);
}
/* Drop privileges before proceeding */
if (getuid() != geteuid() && setuid(geteuid()) < 0)
_exit(1);
if (strcmp(gargv[0], _PATH_LS) == 0) {
/* Reset getopt for ls_main() */
optreset = optind = optopt = 1;
/* Close syslogging to remove pwd.db missing msgs */
closelog();
/* Trigger to sense new /etc/localtime after chroot */
if (getenv("TZ") == NULL) {
setenv("TZ", "", 0);
tzset();
unsetenv("TZ");
tzset();
}
exit(ls_main(gargc, gargv));
}
execv(gargv[0], gargv);
_exit(1);
}
/* parent; assume fdopen can't fail... */
if (*type == 'r') {
iop = fdopen(pdes[0], type);
(void)close(pdes[1]);
} else {
iop = fdopen(pdes[1], type);
(void)close(pdes[0]);
}
pids[fileno(iop)] = pid;
pfree: for (argc = 1; gargv[argc] != NULL; argc++)
free(gargv[argc]);
return (iop);
}
int
ftpd_pclose(FILE *iop)
{
int fdes, omask, status;
pid_t pid;
/*
* pclose returns -1 if stream is not associated with a
* `popened' command, or, if already `pclosed'.
*/
if (pids == NULL || pids[fdes = fileno(iop)] == 0)
return (-1);
(void)fclose(iop);
omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP));
while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR)
continue;
(void)sigsetmask(omask);
pids[fdes] = 0;
if (pid < 0)
return (pid);
if (WIFEXITED(status))
return (WEXITSTATUS(status));
return (1);
}
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