1 /* $NetBSD: popen.c,v 1.38 2016/03/17 00:17:58 christos Exp $ */
2
3 /*-
4 * Copyright (c) 1999-2009 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Luke Mewburn.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 /*
33 * Copyright (c) 1988, 1993, 1994
34 * The Regents of the University of California. All rights reserved.
35 *
36 * This code is derived from software written by Ken Arnold and
37 * published in UNIX Review, Vol. 6, No. 8.
38 *
39 * Redistribution and use in source and binary forms, with or without
40 * modification, are permitted provided that the following conditions
41 * are met:
42 * 1. Redistributions of source code must retain the above copyright
43 * notice, this list of conditions and the following disclaimer.
44 * 2. Redistributions in binary form must reproduce the above copyright
45 * notice, this list of conditions and the following disclaimer in the
46 * documentation and/or other materials provided with the distribution.
47 * 3. Neither the name of the University nor the names of its contributors
48 * may be used to endorse or promote products derived from this software
49 * without specific prior written permission.
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 *
63 */
64
65 #include <sys/cdefs.h>
66 #ifndef lint
67 #if 0
68 static char sccsid[] = "@(#)popen.c 8.3 (Berkeley) 4/6/94";
69 #else
70 __RCSID("$NetBSD: popen.c,v 1.38 2016/03/17 00:17:58 christos Exp $");
71 #endif
72 #endif /* not lint */
73
74 #include <sys/types.h>
75 #include <sys/param.h>
76 #include <sys/wait.h>
77
78 #include <errno.h>
79 #include <glob.h>
80 #include <signal.h>
81 #include <stdio.h>
82 #include <stdlib.h>
83 #include <string.h>
84 #include <stringlist.h>
85 #include <syslog.h>
86 #include <unistd.h>
87
88 #ifdef KERBEROS5
89 #include <krb5/krb5.h>
90 #endif
91
92 #include "extern.h"
93
94 #define INCR 100
95 /*
96 * Special version of popen which avoids call to shell. This ensures no-one
97 * may create a pipe to a hidden program as a side effect of a list or dir
98 * command.
99 * If stderrfd != -1, then send stderr of a read command there,
100 * otherwise close stderr.
101 */
102 static int *pids;
103 static int fds;
104
105 extern int ls_main(int, char *[]);
106
107 FILE *
ftpd_popen(const char * argv[],const char * ptype,int stderrfd)108 ftpd_popen(const char *argv[], const char *ptype, int stderrfd)
109 {
110 FILE * volatile iop;
111 int argc, pdes[2], pid;
112 volatile int isls;
113 char **pop;
114 StringList *sl;
115
116 iop = NULL;
117 isls = 0;
118 if ((*ptype != 'r' && *ptype != 'w') || ptype[1])
119 return (NULL);
120
121 if (!pids) {
122 if ((fds = getdtablesize()) <= 0)
123 return (NULL);
124 if ((pids = (int *)malloc((unsigned int)(fds * sizeof(int)))) == NULL)
125 return (NULL);
126 memset(pids, 0, fds * sizeof(int));
127 }
128 if (pipe(pdes) < 0)
129 return (NULL);
130
131 if ((sl = sl_init()) == NULL)
132 goto pfree;
133
134 /* glob each piece */
135 if (sl_add(sl, ftpd_strdup(argv[0])) == -1)
136 goto pfree;
137 for (argc = 1; argv[argc]; argc++) {
138 glob_t gl;
139 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE|GLOB_LIMIT;
140
141 memset(&gl, 0, sizeof(gl));
142 if (glob(argv[argc], flags, NULL, &gl)
143 || gl.gl_pathv == NULL) {
144 if (sl_add(sl, ftpd_strdup(argv[argc])) == -1) {
145 globfree(&gl);
146 goto pfree;
147 }
148 } else {
149 for (pop = gl.gl_pathv; *pop; pop++) {
150 if (sl_add(sl, ftpd_strdup(*pop)) == -1) {
151 globfree(&gl);
152 goto pfree;
153 }
154 }
155 }
156 globfree(&gl);
157 }
158 if (sl_add(sl, NULL) == -1)
159 goto pfree;
160
161 #ifndef NO_INTERNAL_LS
162 isls = (strcmp(sl->sl_str[0], INTERNAL_LS) == 0);
163 #endif
164
165 pid = isls ? fork() : vfork();
166 switch (pid) {
167 case -1: /* error */
168 (void)close(pdes[0]);
169 (void)close(pdes[1]);
170 goto pfree;
171 /* NOTREACHED */
172 case 0: /* child */
173 if (*ptype == 'r') {
174 if (pdes[1] != STDOUT_FILENO) {
175 dup2(pdes[1], STDOUT_FILENO);
176 (void)close(pdes[1]);
177 }
178 if (stderrfd == -1)
179 (void)close(STDERR_FILENO);
180 else
181 dup2(stderrfd, STDERR_FILENO);
182 (void)close(pdes[0]);
183 } else {
184 if (pdes[0] != STDIN_FILENO) {
185 dup2(pdes[0], STDIN_FILENO);
186 (void)close(pdes[0]);
187 }
188 (void)close(pdes[1]);
189 }
190 #ifndef NO_INTERNAL_LS
191 if (isls) { /* use internal ls */
192 optreset = optind = optopt = 1;
193 closelog();
194 exit(ls_main(sl->sl_cur - 1, sl->sl_str));
195 }
196 #endif
197
198 execv(sl->sl_str[0], sl->sl_str);
199 _exit(1);
200 }
201 /* parent; assume fdopen can't fail... */
202 if (*ptype == 'r') {
203 iop = fdopen(pdes[0], ptype);
204 (void)close(pdes[1]);
205 } else {
206 iop = fdopen(pdes[1], ptype);
207 (void)close(pdes[0]);
208 }
209 pids[fileno(iop)] = pid;
210
211 pfree:
212 if (sl)
213 sl_free(sl, 1);
214 return (iop);
215 }
216
217 int
ftpd_pclose(FILE * iop)218 ftpd_pclose(FILE *iop)
219 {
220 int fdes, status;
221 pid_t pid;
222 sigset_t nsigset, osigset;
223
224 /*
225 * pclose returns -1 if stream is not associated with a
226 * `popened' command, or, if already `pclosed'.
227 */
228 if (pids == 0 || pids[fdes = fileno(iop)] == 0)
229 return (-1);
230 (void)fclose(iop);
231 sigemptyset(&nsigset);
232 sigaddset(&nsigset, SIGINT);
233 sigaddset(&nsigset, SIGQUIT);
234 sigaddset(&nsigset, SIGHUP);
235 sigprocmask(SIG_BLOCK, &nsigset, &osigset);
236 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR)
237 continue;
238 sigprocmask(SIG_SETMASK, &osigset, NULL);
239 pids[fdes] = 0;
240 if (pid < 0)
241 return (pid);
242 if (WIFEXITED(status))
243 return (WEXITSTATUS(status));
244 return (1);
245 }
246