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/* $OpenBSD: popen.c,v 1.29 2020/01/15 22:06:59 jan Exp $ */
/* $NetBSD: popen.c,v 1.5 1995/04/11 02:45:00 cgd Exp $ */
/*
* 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.
*
*/
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <glob.h>
#include <limits.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <netinet/in.h>
#include "monitor.h"
#include "extern.h"
/*
* 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.
*/
FILE *
ftpd_ls(const char *path, pid_t *pidptr)
{
char *cp;
FILE *iop;
int argc = 0, pdes[2];
pid_t pid;
char **pop, *argv[_POSIX_ARG_MAX];
if (pipe(pdes) == -1)
return (NULL);
/* break up string into pieces */
argv[argc++] = "/bin/ls";
argv[argc++] = "-lgA";
argv[argc++] = "--";
/* glob that path */
if (path != NULL) {
glob_t gl;
memset(&gl, 0, sizeof(gl));
if (glob(path,
GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT,
NULL, &gl)) {
fatal ("Glob error.");
} else if (gl.gl_pathc > 0) {
for (pop = gl.gl_pathv; *pop && argc < _POSIX_ARG_MAX-1;
pop++) {
argv[argc++] = strdup(*pop);
if (argv[argc - 1] == NULL)
fatal ("Out of memory.");
}
}
globfree(&gl);
}
argv[argc] = NULL;
iop = NULL;
switch (pid = fork()) {
case -1: /* error */
(void)close(pdes[0]);
(void)close(pdes[1]);
goto pfree;
/* NOTREACHED */
case 0: /* child */
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]);
closelog();
extern int optreset;
extern int ls_main(int, char **);
/* reset getopt for ls_main */
optreset = optind = 1;
exit(ls_main(argc, argv));
}
/* parent; assume fdopen can't fail... */
iop = fdopen(pdes[0], "r");
(void)close(pdes[1]);
*pidptr = pid;
pfree:
for (argc = 3; argv[argc] != NULL; argc++)
free(argv[argc]);
return (iop);
}
int
ftpd_pclose(FILE *iop, pid_t pid)
{
int status;
pid_t rv;
sigset_t sigset, osigset;
(void)fclose(iop);
sigemptyset(&sigset);
sigaddset(&sigset, SIGINT);
sigaddset(&sigset, SIGQUIT);
sigaddset(&sigset, SIGHUP);
sigprocmask(SIG_BLOCK, &sigset, &osigset);
while ((rv = waitpid(pid, &status, 0)) == -1 && errno == EINTR)
continue;
sigprocmask(SIG_SETMASK, &osigset, NULL);
if (rv == -1)
return (-1);
if (WIFEXITED(status))
return (WEXITSTATUS(status));
return (1);
}
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