1 /*-
2  * Copyright (c) 2007 Joerg Sonnenberger
3  * Copyright (c) 2012 Michihiro NAKAJIMA
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include "archive_platform.h"
28 
29 /* This capability is only available on POSIX systems. */
30 #if defined(HAVE_PIPE) && defined(HAVE_FCNTL) && \
31     (defined(HAVE_FORK) || defined(HAVE_VFORK) || defined(HAVE_POSIX_SPAWNP))
32 
33 __FBSDID("$FreeBSD: head/lib/libarchive/filter_fork.c 182958 2008-09-12 05:33:00Z kientzle $");
34 
35 #if defined(HAVE_SYS_TYPES_H)
36 #  include <sys/types.h>
37 #endif
38 #ifdef HAVE_ERRNO_H
39 #  include <errno.h>
40 #endif
41 #ifdef HAVE_STRING_H
42 #  include <string.h>
43 #endif
44 #if defined(HAVE_POLL) && (defined(HAVE_POLL_H) || defined(HAVE_SYS_POLL_H))
45 #  if defined(HAVE_POLL_H)
46 #    include <poll.h>
47 #  elif defined(HAVE_SYS_POLL_H)
48 #    include <sys/poll.h>
49 #  endif
50 #elif defined(HAVE_SELECT)
51 #  if defined(HAVE_SYS_SELECT_H)
52 #    include <sys/select.h>
53 #  elif defined(HAVE_UNISTD_H)
54 #    include <unistd.h>
55 #  endif
56 #endif
57 #ifdef HAVE_FCNTL_H
58 #  include <fcntl.h>
59 #endif
60 #ifdef HAVE_SPAWN_H
61 #  include <spawn.h>
62 #endif
63 #ifdef HAVE_STDLIB_H
64 #  include <stdlib.h>
65 #endif
66 #ifdef HAVE_UNISTD_H
67 #  include <unistd.h>
68 #endif
69 
70 #include "archive.h"
71 #include "archive_cmdline_private.h"
72 
73 #include "filter_fork.h"
74 
75 int
76 __archive_create_child(const char *cmd, int *child_stdin, int *child_stdout,
77 		pid_t *out_child)
78 {
79 	pid_t child;
80 	int stdin_pipe[2], stdout_pipe[2], tmp;
81 #if HAVE_POSIX_SPAWNP
82 	posix_spawn_file_actions_t actions;
83 	int r;
84 #endif
85 	struct archive_cmdline *cmdline;
86 
87 	cmdline = __archive_cmdline_allocate();
88 	if (cmdline == NULL)
89 		goto state_allocated;
90 	if (__archive_cmdline_parse(cmdline, cmd) != ARCHIVE_OK)
91 		goto state_allocated;
92 
93 	if (pipe(stdin_pipe) == -1)
94 		goto state_allocated;
95 	if (stdin_pipe[0] == 1 /* stdout */) {
96 		if ((tmp = dup(stdin_pipe[0])) == -1)
97 			goto stdin_opened;
98 		close(stdin_pipe[0]);
99 		stdin_pipe[0] = tmp;
100 	}
101 	if (pipe(stdout_pipe) == -1)
102 		goto stdin_opened;
103 	if (stdout_pipe[1] == 0 /* stdin */) {
104 		if ((tmp = dup(stdout_pipe[1])) == -1)
105 			goto stdout_opened;
106 		close(stdout_pipe[1]);
107 		stdout_pipe[1] = tmp;
108 	}
109 
110 #if HAVE_POSIX_SPAWNP
111 
112 	r = posix_spawn_file_actions_init(&actions);
113 	if (r != 0) {
114 		errno = r;
115 		goto stdout_opened;
116 	}
117 	r = posix_spawn_file_actions_addclose(&actions, stdin_pipe[1]);
118 	if (r != 0)
119 		goto actions_inited;
120 	r = posix_spawn_file_actions_addclose(&actions, stdout_pipe[0]);
121 	if (r != 0)
122 		goto actions_inited;
123 	/* Setup for stdin. */
124 	r = posix_spawn_file_actions_adddup2(&actions, stdin_pipe[0], 0);
125 	if (r != 0)
126 		goto actions_inited;
127 	if (stdin_pipe[0] != 0 /* stdin */) {
128 		r = posix_spawn_file_actions_addclose(&actions, stdin_pipe[0]);
129 		if (r != 0)
130 			goto actions_inited;
131 	}
132 	/* Setup for stdout. */
133 	r = posix_spawn_file_actions_adddup2(&actions, stdout_pipe[1], 1);
134 	if (r != 0)
135 		goto actions_inited;
136 	if (stdout_pipe[1] != 1 /* stdout */) {
137 		r = posix_spawn_file_actions_addclose(&actions, stdout_pipe[1]);
138 		if (r != 0)
139 			goto actions_inited;
140 	}
141 	r = posix_spawnp(&child, cmdline->path, &actions, NULL,
142 		cmdline->argv, NULL);
143 	if (r != 0)
144 		goto actions_inited;
145 	posix_spawn_file_actions_destroy(&actions);
146 
147 #else /* HAVE_POSIX_SPAWNP */
148 
149 #if HAVE_VFORK
150 	child = vfork();
151 #else
152 	child = fork();
153 #endif
154 	if (child == -1)
155 		goto stdout_opened;
156 	if (child == 0) {
157 		close(stdin_pipe[1]);
158 		close(stdout_pipe[0]);
159 		if (dup2(stdin_pipe[0], 0 /* stdin */) == -1)
160 			_exit(254);
161 		if (stdin_pipe[0] != 0 /* stdin */)
162 			close(stdin_pipe[0]);
163 		if (dup2(stdout_pipe[1], 1 /* stdout */) == -1)
164 			_exit(254);
165 		if (stdout_pipe[1] != 1 /* stdout */)
166 			close(stdout_pipe[1]);
167 		execvp(cmdline->path, cmdline->argv);
168 		_exit(254);
169 	}
170 #endif /* HAVE_POSIX_SPAWNP */
171 
172 	close(stdin_pipe[0]);
173 	close(stdout_pipe[1]);
174 
175 	*child_stdin = stdin_pipe[1];
176 	fcntl(*child_stdin, F_SETFL, O_NONBLOCK);
177 	*child_stdout = stdout_pipe[0];
178 	fcntl(*child_stdout, F_SETFL, O_NONBLOCK);
179 	__archive_cmdline_free(cmdline);
180 
181 	*out_child = child;
182 	return ARCHIVE_OK;
183 
184 #if HAVE_POSIX_SPAWNP
185 actions_inited:
186 	errno = r;
187 	posix_spawn_file_actions_destroy(&actions);
188 #endif
189 stdout_opened:
190 	close(stdout_pipe[0]);
191 	close(stdout_pipe[1]);
192 stdin_opened:
193 	close(stdin_pipe[0]);
194 	close(stdin_pipe[1]);
195 state_allocated:
196 	__archive_cmdline_free(cmdline);
197 	return ARCHIVE_FAILED;
198 }
199 
200 void
201 __archive_check_child(int in, int out)
202 {
203 #if defined(HAVE_POLL) && (defined(HAVE_POLL_H) || defined(HAVE_SYS_POLL_H))
204 	struct pollfd fds[2];
205 	int idx;
206 
207 	idx = 0;
208 	if (in != -1) {
209 		fds[idx].fd = in;
210 		fds[idx].events = POLLOUT;
211 		++idx;
212 	}
213 	if (out != -1) {
214 		fds[idx].fd = out;
215 		fds[idx].events = POLLIN;
216 		++idx;
217 	}
218 
219 	poll(fds, idx, -1); /* -1 == INFTIM, wait forever */
220 #elif defined(HAVE_SELECT)
221 	fd_set fds_in, fds_out, fds_error;
222 
223 	FD_ZERO(&fds_in);
224 	FD_ZERO(&fds_out);
225 	FD_ZERO(&fds_error);
226 	if (out != -1) {
227 		FD_SET(out, &fds_in);
228 		FD_SET(out, &fds_error);
229 	}
230 	if (in != -1) {
231 		FD_SET(in, &fds_out);
232 		FD_SET(in, &fds_error);
233 	}
234 	select(in < out ? out + 1 : in + 1, &fds_in, &fds_out, &fds_error, NULL);
235 #else
236 	sleep(1);
237 #endif
238 }
239 
240 #endif /* defined(HAVE_PIPE) && defined(HAVE_VFORK) && defined(HAVE_FCNTL) */
241