2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
21 * @brief Execute external programs.
23 * @copyright 2000-2004,2006 The FreeRADIUS server project
28 #include <freeradius-devel/radiusd.h>
29 #include <freeradius-devel/rad_assert.h>
37 #ifdef HAVE_SYS_WAIT_H
38 # include <sys/wait.h>
41 # define WEXITSTATUS(stat_val) ((unsigned)(stat_val) >> 8)
44 # define WIFEXITED(stat_val) (((stat_val) & 255) == 0)
47 #define MAX_ARGV (256)
50 static void tv_sub(struct timeval *end, struct timeval *start,
51 struct timeval *elapsed)
53 elapsed->tv_sec = end->tv_sec - start->tv_sec;
54 if (elapsed->tv_sec > 0) {
56 elapsed->tv_usec = USEC;
60 elapsed->tv_usec += end->tv_usec;
61 elapsed->tv_usec -= start->tv_usec;
63 if (elapsed->tv_usec >= USEC) {
64 elapsed->tv_usec -= USEC;
72 * @param cmd Command to execute. This is parsed into argv[] parts,
73 * then each individual argv part is xlat'ed.
74 * @param request Current reuqest
75 * @param exec_wait set to 1 if you want to read from or write to child
76 * @param[in,out] input_fd pointer to int, receives the stdin file.
77 * descriptor. Set to NULL and the child will have /dev/null on stdin
78 * @param[in,out] output_fd pinter to int, receives the stdout file
79 * descriptor. Set to NULL and child will have /dev/null on stdout.
80 * @param input_pairs list of value pairs - these will be put into
81 * the environment variables of the child.
82 * @param shell_escape values before passing them as arguments.
83 * @return PID of the child process, -1 on error.
85 pid_t radius_start_program(char const *cmd, REQUEST *request, bool exec_wait,
86 int *input_fd, int *output_fd,
87 VALUE_PAIR *input_pairs, bool shell_escape)
93 int to_child[2] = {-1, -1};
94 int from_child[2] = {-1, -1};
101 #define MAX_ENVP 1024
102 char *envp[MAX_ENVP];
104 argc = rad_expand_xlat(request, cmd, MAX_ARGV, argv, true, sizeof(argv_buf), argv_buf);
106 RDEBUG("invalid command line '%s'.", cmd);
112 if (debug_flag > 2) {
113 RDEBUG3("executing cmd %s", cmd);
114 for (i = 0; i < argc; i++) {
115 RDEBUG3("\t[%d] %s", i, argv[i]);
122 * Open a pipe for child/parent communication, if necessary.
126 if (pipe(to_child) != 0) {
127 RDEBUG("Couldn't open pipe to child: %s", strerror(errno));
132 if (pipe(from_child) != 0) {
133 RDEBUG("Couldn't open pipe from child: %s", strerror(errno));
134 /* safe because these either need closing or are == -1 */
150 * Set up the environment variables in the
151 * parent, so we don't call libc functions that
152 * hold mutexes. They might be locked when we fork,
153 * and will remain locked in the child.
157 for (vp = paircursor(&cursor, &input_pairs); vp; vp = pairnext(&cursor)) {
159 * Hmm... maybe we shouldn't pass the
160 * user's password in an environment
163 snprintf(buffer, sizeof(buffer), "%s=", vp->da->name);
165 for (p = buffer; *p != '='; p++) {
168 } else if (isalpha((int) *p)) {
175 vp_prints_value(buffer+n, sizeof(buffer) - n, vp, shell_escape ? '"' : 0);
177 envp[envlen++] = strdup(buffer);
180 * Don't add too many attributes.
182 if (envlen == (MAX_ENVP - 1)) break;
188 pid = rad_fork(); /* remember PID */
190 pid = fork(); /* don't wait */
199 * We try to be fail-safe here. So if ANYTHING
200 * goes wrong, we exit with status 1.
204 * Open STDIN to /dev/null
206 devnull = open("/dev/null", O_RDWR);
208 RDEBUG("Failed opening /dev/null: %s\n", strerror(errno));
211 * Where the status code is interpreted as a module rcode
212 * one is subtracted from it, to allow 0 to equal success
214 * 2 is RLM_MODULE_FAIL + 1
220 * Only massage the pipe handles if the parent
226 dup2(to_child[0], STDIN_FILENO);
228 dup2(devnull, STDIN_FILENO);
232 close(from_child[0]);
233 dup2(from_child[1], STDOUT_FILENO);
235 dup2(devnull, STDOUT_FILENO);
238 } else { /* no pipe, STDOUT should be /dev/null */
239 dup2(devnull, STDIN_FILENO);
240 dup2(devnull, STDOUT_FILENO);
244 * If we're not debugging, then we can't do
245 * anything with the error messages, so we throw
248 * If we are debugging, then we want the error
249 * messages to go to the STDERR of the server.
251 if (debug_flag == 0) {
252 dup2(devnull, STDERR_FILENO);
257 * The server may have MANY FD's open. We don't
258 * want to leave dangling FD's for the child process
259 * to play funky games with, so we close them.
264 * I swear the signature for execve is wrong and should take 'char const * const argv[]'.
266 execve(argv[0], argv, envp);
267 printf("Failed to execute \"%s\": %s", argv[0], strerror(errno)); /* fork output will be captured */
270 * Where the status code is interpreted as a module rcode
271 * one is subtracted from it, to allow 0 to equal success
273 * 2 is RLM_MODULE_FAIL + 1
279 * Free child environment variables
281 for (i = 0; envp[i] != NULL; i++) {
289 RDEBUG("Couldn't fork %s: %s", argv[0], strerror(errno));
291 /* safe because these either need closing or are == -1 */
294 close(from_child[0]);
295 close(from_child[1]);
301 * We're not waiting, exit, and ignore any child's status.
305 * Close the ends of the pipe(s) the child is using
306 * return the ends of the pipe(s) our caller wants
310 *input_fd = to_child[1];
314 *output_fd = from_child[0];
315 close(from_child[1]);
322 RDEBUG("Wait is not supported");
328 * The _spawn and _exec families of functions are
329 * found in Windows compiler libraries for
330 * portability from UNIX. There is a variety of
331 * functions, including the ability to pass
332 * either a list or array of parameters, to
333 * search in the PATH or otherwise, and whether
334 * or not to pass an environment (a set of
335 * environment variables). Using _spawn, you can
336 * also specify whether you want the new process
337 * to close your program (_P_OVERLAY), to wait
338 * until the new process is finished (_P_WAIT) or
339 * for the two to run concurrently (_P_NOWAIT).
341 * _spawn and _exec are useful for instances in
342 * which you have simple requirements for running
343 * the program, don't want the overhead of the
344 * Windows header file, or are interested
345 * primarily in portability.
349 * FIXME: check return code... what is it?
351 _spawnve(_P_NOWAIT, argv[0], argv, envp);
358 /** Read from the child process.
360 * @param request The current request.
361 * @param fd file descriptor to read from.
362 * @param pid pid of child, will be reaped if it dies.
363 * @param timeout amount of time to wait, in seconds.
364 * @param answer buffer to write into.
365 * @param left length of buffer.
366 * @return -1 on error, or length of output.
368 int radius_readfrom_program(REQUEST *request, int fd, pid_t pid, int timeout,
369 char *answer, int left)
374 struct timeval start;
381 * Try to set it non-blocking.
386 if ((flags = fcntl(fd, F_GETFL, NULL)) < 0) {
392 if( fcntl(fd, F_SETFL, flags) < 0) {
401 * Read from the pipe until we doesn't get any more or
402 * until the message is full.
404 gettimeofday(&start, NULL);
408 struct timeval when, elapsed, wake;
413 gettimeofday(&when, NULL);
414 tv_sub(&when, &start, &elapsed);
415 if (elapsed.tv_sec >= timeout) goto too_long;
417 when.tv_sec = timeout;
419 tv_sub(&when, &elapsed, &wake);
421 rcode = select(fd + 1, &fds, NULL, NULL, &wake);
424 RDEBUG("Child PID %u is taking too much time: forcing failure and killing child.", pid);
426 close(fd); /* should give SIGPIPE to child, too */
429 * Clean up the child entry.
431 rad_waitpid(pid, &status);
435 if (errno == EINTR) continue;
441 * Read as many bytes as possible. The kernel
442 * will return the number of bytes available.
445 status = read(fd, answer + done, left);
449 * There's at least 1 byte ready: read it.
451 status = read(fd, answer + done, 1);
454 * Nothing more to read: stop.
461 * Error: See if we have to continue.
465 * We were interrupted: continue reading.
467 if (errno == EINTR) {
472 * There was another error. Most likely
473 * The child process has finished, and
481 if (left <= 0) break;
483 #endif /* __MINGW32__ */
487 /** Execute a program.
489 * @param[in] request Current request.
490 * @param[in] cmd Command to execute. This is parsed into argv[] parts, then each individual argv part
492 * @param[in] exec_wait set to 1 if you want to read from or write to child.
493 * @param[in] shell_escape values before passing them as arguments.
494 * @param[in] user_msg buffer to append plaintext (non valuepair) output.
495 * @param[in] msg_len length of user_msg buffer.
496 * @param[in] timeout amount of time to wait, in seconds.
497 * @param[in] input_pairs list of value pairs - these will be available in the environment of the child.
498 * @param[out] output_pairs list of value pairs - child stdout will be parsed and added into this list
500 * @return 0 if exec_wait==0, exit code if exec_wait!=0, -1 on error.
502 int radius_exec_program(REQUEST *request, char const *cmd, bool exec_wait, bool shell_escape,
503 char *user_msg, size_t msg_len, int timeout,
504 VALUE_PAIR *input_pairs, VALUE_PAIR **output_pairs)
518 RDEBUG2("Executing: \"%s\"", cmd);
520 if (user_msg) *user_msg = '\0';
522 pid = radius_start_program(cmd, request, exec_wait, NULL, &from_child, input_pairs, shell_escape);
532 done = radius_readfrom_program(request, from_child, pid, timeout, answer, sizeof(answer));
535 * failure - radius_readfrom_program will
536 * have called close(from_child) for us
538 DEBUG("Failed to read from child output");
545 * Make sure that the writer can't block while writing to
546 * a pipe that no one is reading from anymore.
551 * Parse the output, if any.
557 * For backwards compatibility, first check
558 * for plain text (user_msg).
561 n = userparse(request, answer, &vp);
567 if (n == T_OP_INVALID) {
569 strlcpy(user_msg, answer, msg_len);
573 * HACK: Replace '\n' with ',' so that
574 * userparse() can parse the buffer in
575 * one go (the proper way would be to
576 * fix userparse(), but oh well).
578 for (p = answer; *p; p++) {
580 *p = comma ? ' ' : ',';
584 if (*p == ',') comma++;
588 * Replace any trailing comma by a NUL.
590 if (answer[strlen(answer) - 1] == ',') {
591 answer[strlen(answer) - 1] = '\0';
594 if (userparse(request, answer, &vp) == T_OP_INVALID) {
595 REDEBUG("Unparsable reply from '%s'", cmd);
600 * Tell the caller about the value
605 } /* else the answer was a set of VP's, not a text message */
606 } /* else we didn't read anything from the child */
609 * Call rad_waitpid (should map to waitpid on non-threaded
610 * or single-server systems).
612 child_pid = rad_waitpid(pid, &status);
613 if (child_pid == 0) {
614 REDEBUG("Timeout waiting for child");
619 if (child_pid == pid) {
620 if (WIFEXITED(status)) {
621 status = WEXITSTATUS(status);
623 RDEBUG("Program returned code (%d): %s", status, answer);
629 REDEBUG("Abnormal child exit: %s", strerror(errno));
630 #endif /* __MINGW32__ */