1 /*
2 * Copyright (c) 1988, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software written by Ken Arnold and
6 * published in UNIX Review, Vol. 6, No. 8.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)popen.c 8.3 (Berkeley) 4/6/94
33 * $FreeBSD: src/libexec/ftpd/popen.c,v 1.26 2004/11/18 13:46:29 yar Exp $
34 */
35
36 #include <sys/types.h>
37 #include <sys/wait.h>
38 #include <netinet/in.h>
39
40 #include <errno.h>
41 #include <glob.h>
42 #include <signal.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47
48 #include "extern.h"
49 #include "pathnames.h"
50 #include <syslog.h>
51 #include <time.h>
52
53 #define MAXUSRARGS 100
54 #define MAXGLOBARGS 1000
55
56 /*
57 * Special version of popen which avoids call to shell. This ensures noone
58 * may create a pipe to a hidden program as a side effect of a list or dir
59 * command.
60 */
61 static int *pids;
62 static int fds;
63
64 FILE *
ftpd_popen(char * program,char * type)65 ftpd_popen(char *program, char *type)
66 {
67 char *cp;
68 FILE *iop;
69 int argc, gargc, pdes[2], pid;
70 char **pop, *argv[MAXUSRARGS], *gargv[MAXGLOBARGS];
71
72 if (((*type != 'r') && (*type != 'w')) || type[1])
73 return (NULL);
74
75 if (!pids) {
76 if ((fds = getdtablesize()) <= 0)
77 return (NULL);
78 if ((pids = malloc(fds * sizeof(int))) == NULL)
79 return (NULL);
80 memset(pids, 0, fds * sizeof(int));
81 }
82 if (pipe(pdes) < 0)
83 return (NULL);
84
85 /* break up string into pieces */
86 for (argc = 0, cp = program; argc < MAXUSRARGS; cp = NULL) {
87 if (!(argv[argc++] = strtok(cp, " \t\n")))
88 break;
89 }
90 argv[argc - 1] = NULL;
91
92 /* glob each piece */
93 gargv[0] = argv[0];
94 for (gargc = argc = 1; argv[argc] && gargc < (MAXGLOBARGS-1); argc++) {
95 glob_t gl;
96 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
97
98 memset(&gl, 0, sizeof(gl));
99 gl.gl_matchc = MAXGLOBARGS;
100 /*flags |= GLOB_LIMIT;*/
101 if (glob(argv[argc], flags, NULL, &gl))
102 gargv[gargc++] = strdup(argv[argc]);
103 else
104 for (pop = gl.gl_pathv; *pop && gargc < (MAXGLOBARGS-1);
105 pop++)
106 gargv[gargc++] = strdup(*pop);
107 globfree(&gl);
108 }
109 gargv[gargc] = NULL;
110
111 iop = NULL;
112 fflush(NULL);
113 pid = (strcmp(gargv[0], _PATH_LS) == 0) ? fork() : vfork();
114 switch(pid) {
115 case -1: /* error */
116 close(pdes[0]);
117 close(pdes[1]);
118 goto pfree;
119 /* NOTREACHED */
120 case 0: /* child */
121 if (*type == 'r') {
122 if (pdes[1] != STDOUT_FILENO) {
123 dup2(pdes[1], STDOUT_FILENO);
124 close(pdes[1]);
125 }
126 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */
127 close(pdes[0]);
128 } else {
129 if (pdes[0] != STDIN_FILENO) {
130 dup2(pdes[0], STDIN_FILENO);
131 close(pdes[0]);
132 }
133 close(pdes[1]);
134 }
135 if (strcmp(gargv[0], _PATH_LS) == 0) {
136 /* Reset getopt for ls_main() */
137 optreset = optind = optopt = 1;
138 /* Close syslogging to remove pwd.db missing msgs */
139 closelog();
140 /* Trigger to sense new /etc/localtime after chroot */
141 if (getenv("TZ") == NULL) {
142 if (setenv("TZ", "", 0) == -1)
143 syslog(LOG_ERR, "setenv: cannot set TZ: %m");
144 tzset();
145 unsetenv("TZ");
146 tzset();
147 }
148 exit(ls_main(gargc, gargv));
149 }
150 execv(gargv[0], gargv);
151 _exit(1);
152 }
153 /* parent; assume fdopen can't fail... */
154 if (*type == 'r') {
155 iop = fdopen(pdes[0], type);
156 close(pdes[1]);
157 } else {
158 iop = fdopen(pdes[1], type);
159 close(pdes[0]);
160 }
161 pids[fileno(iop)] = pid;
162
163 pfree: for (argc = 1; gargv[argc] != NULL; argc++)
164 free(gargv[argc]);
165
166 return (iop);
167 }
168
169 int
ftpd_pclose(FILE * iop)170 ftpd_pclose(FILE *iop)
171 {
172 int fdes, omask, status;
173 pid_t pid;
174
175 /*
176 * pclose returns -1 if stream is not associated with a
177 * `popened' command, or, if already `pclosed'.
178 */
179 if (pids == NULL || pids[fdes = fileno(iop)] == 0)
180 return (-1);
181 fclose(iop);
182 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP));
183 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR)
184 continue;
185 sigsetmask(omask);
186 pids[fdes] = 0;
187 if (pid < 0)
188 return (pid);
189 if (WIFEXITED(status))
190 return (WEXITSTATUS(status));
191 return (1);
192 }
193