2 Unix SMB/CIFS implementation.
4 winbind client common code
6 Copyright (C) Tim Potter 2000
7 Copyright (C) Andrew Tridgell 2000
8 Copyright (C) Andrew Bartlett 2002
9 Copyright (C) Matthew Newton 2015
12 This library is free software; you can redistribute it and/or
13 modify it under the terms of the GNU Lesser General Public
14 License as published by the Free Software Foundation; either
15 version 3 of the License, or (at your option) any later version.
17 This library is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 Library General Public License for more details.
22 You should have received a copy of the GNU Lesser General Public License
23 along with this program. If not, see <http://www.gnu.org/licenses/>.
27 #include "system/select.h"
28 #include "winbind_client.h"
34 static char client_name[32];
38 struct winbindd_context {
39 int winbindd_fd; /* winbind file descriptor */
40 bool is_privileged; /* using the privileged socket? */
41 pid_t our_pid; /* calling process pid */
45 static pthread_mutex_t wb_global_ctx_mutex = PTHREAD_MUTEX_INITIALIZER;
48 static struct winbindd_context *get_wb_global_ctx(void)
50 static struct winbindd_context wb_global_ctx = {
52 .is_privileged = false,
57 pthread_mutex_lock(&wb_global_ctx_mutex);
59 return &wb_global_ctx;
62 static void put_wb_global_ctx(void)
65 pthread_mutex_unlock(&wb_global_ctx_mutex);
70 /* Free a response structure */
72 void winbindd_free_response(struct winbindd_response *response)
74 /* Free any allocated extra_data */
77 SAFE_FREE(response->extra_data.data);
80 void winbind_set_client_name(const char *name)
82 if (name == NULL || strlen(name) == 0) {
86 (void)snprintf(client_name, sizeof(client_name), "%s", name);
89 static const char *winbind_get_client_name(void)
91 if (client_name[0] == '\0') {
92 const char *progname = getprogname();
95 if (progname == NULL) {
96 progname = "<unknown>";
99 len = snprintf(client_name,
111 /* Initialise a request structure */
113 static void winbindd_init_request(struct winbindd_request *request,
116 request->length = sizeof(struct winbindd_request);
118 request->cmd = (enum winbindd_cmd)request_type;
119 request->pid = getpid();
121 (void)snprintf(request->client_name,
122 sizeof(request->client_name),
124 winbind_get_client_name());
127 /* Initialise a response structure */
129 static void init_response(struct winbindd_response *response)
131 /* Initialise return value */
133 response->result = WINBINDD_ERROR;
136 /* Close established socket */
138 static void winbind_close_sock(struct winbindd_context *ctx)
144 if (ctx->winbindd_fd != -1) {
145 close(ctx->winbindd_fd);
146 ctx->winbindd_fd = -1;
150 /* Destructor for global context to ensure fd is closed */
152 #ifdef HAVE_DESTRUCTOR_ATTRIBUTE
153 __attribute__((destructor))
155 static void winbind_destructor(void)
157 struct winbindd_context *ctx;
159 ctx = get_wb_global_ctx();
160 winbind_close_sock(ctx);
164 #define CONNECT_TIMEOUT 30
166 /* Make sure socket handle isn't stdin, stdout or stderr */
167 #define RECURSION_LIMIT 3
169 static int make_nonstd_fd_internals(int fd, int limit /* Recursion limiter */)
172 if (fd >= 0 && fd <= 2) {
174 if ((new_fd = fcntl(fd, F_DUPFD, 3)) == -1) {
192 /* use the program stack to hold our list of FDs to close */
193 new_fd = make_nonstd_fd_internals(new_fd, limit - 1);
201 /****************************************************************************
202 Set a fd into blocking/nonblocking mode. Uses POSIX O_NONBLOCK if available,
206 Set close on exec also.
207 ****************************************************************************/
209 static int make_safe_fd(int fd)
212 int new_fd = make_nonstd_fd_internals(fd, RECURSION_LIMIT);
218 /* Socket should be nonblocking. */
220 #define FLAG_TO_SET O_NONBLOCK
223 #define FLAG_TO_SET O_NDELAY
225 #define FLAG_TO_SET FNDELAY
229 if ((flags = fcntl(new_fd, F_GETFL)) == -1) {
234 flags |= FLAG_TO_SET;
235 if (fcntl(new_fd, F_SETFL, flags) == -1) {
242 /* Socket should be closed on exec() */
244 result = flags = fcntl(new_fd, F_GETFD, 0);
247 result = fcntl( new_fd, F_SETFD, flags );
260 * @brief Check if we talk to the priviliged pipe which should be owned by root.
262 * This checks if we have uid_wrapper running and if this is the case it will
263 * allow one to connect to the winbind privileged pipe even it is not owned by root.
265 * @param[in] uid The uid to check if we can safely talk to the pipe.
267 * @return If we have access it returns true, else false.
269 static bool winbind_privileged_pipe_is_root(uid_t uid)
275 if (uid_wrapper_enabled()) {
282 /* Connect to winbindd socket */
284 static int winbind_named_pipe_sock(const char *dir)
286 struct sockaddr_un sunaddr;
293 /* Check permissions on unix socket directory */
295 if (lstat(dir, &st) == -1) {
301 * This tells us that the pipe is owned by a privileged
302 * process, as we will be sending passwords to it.
304 if (!S_ISDIR(st.st_mode) ||
305 !winbind_privileged_pipe_is_root(st.st_uid)) {
310 /* Connect to socket */
312 sunaddr = (struct sockaddr_un) { .sun_family = AF_UNIX };
314 ret = snprintf(sunaddr.sun_path, sizeof(sunaddr.sun_path),
315 "%s/%s", dir, WINBINDD_SOCKET_NAME);
316 if ((ret == -1) || (ret >= sizeof(sunaddr.sun_path))) {
317 errno = ENAMETOOLONG;
321 /* If socket file doesn't exist, don't bother trying to connect
322 with retry. This is an attempt to make the system usable when
323 the winbindd daemon is not running. */
325 if (lstat(sunaddr.sun_path, &st) == -1) {
330 /* Check permissions on unix socket file */
333 * This tells us that the pipe is owned by a privileged
334 * process, as we will be sending passwords to it.
336 if (!S_ISSOCK(st.st_mode) ||
337 !winbind_privileged_pipe_is_root(st.st_uid)) {
342 /* Connect to socket */
344 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
348 /* Set socket non-blocking and close on exec. */
350 if ((fd = make_safe_fd( fd)) == -1) {
354 for (wait_time = 0; connect(fd, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) == -1;
355 wait_time += slept) {
357 int connect_errno = 0;
360 if (wait_time >= CONNECT_TIMEOUT)
366 pfd.events = POLLOUT;
368 ret = poll(&pfd, 1, (CONNECT_TIMEOUT - wait_time) * 1000);
371 errnosize = sizeof(connect_errno);
373 ret = getsockopt(fd, SOL_SOCKET,
374 SO_ERROR, &connect_errno, &errnosize);
376 if (ret >= 0 && connect_errno == 0) {
377 /* Connect succeed */
382 slept = CONNECT_TIMEOUT;
385 slept = rand() % 3 + 1;
404 static const char *winbindd_socket_dir(void)
406 if (nss_wrapper_enabled()) {
409 env_dir = getenv("SELFTEST_WINBINDD_SOCKET_DIR");
410 if (env_dir != NULL) {
415 return WINBINDD_SOCKET_DIR;
418 /* Connect to winbindd socket */
420 static int winbind_open_pipe_sock(struct winbindd_context *ctx,
421 int recursing, int need_priv)
423 #ifdef HAVE_UNIXSOCKET
424 struct winbindd_request request;
425 struct winbindd_response response;
427 ZERO_STRUCT(request);
428 ZERO_STRUCT(response);
434 if (ctx->our_pid != getpid()) {
435 winbind_close_sock(ctx);
436 ctx->our_pid = getpid();
439 if ((need_priv != 0) && !ctx->is_privileged) {
440 winbind_close_sock(ctx);
443 if (ctx->winbindd_fd != -1) {
444 return ctx->winbindd_fd;
451 ctx->winbindd_fd = winbind_named_pipe_sock(winbindd_socket_dir());
453 if (ctx->winbindd_fd == -1) {
457 ctx->is_privileged = false;
459 /* version-check the socket */
461 request.wb_flags = WBFLAG_RECURSE;
462 if ((winbindd_request_response(ctx, WINBINDD_INTERFACE_VERSION, &request,
463 &response) != NSS_STATUS_SUCCESS) ||
464 (response.data.interface_version != WINBIND_INTERFACE_VERSION)) {
465 winbind_close_sock(ctx);
469 if (need_priv == 0) {
470 return ctx->winbindd_fd;
473 /* try and get priv pipe */
475 request.wb_flags = WBFLAG_RECURSE;
477 /* Note that response needs to be initialized to avoid
478 * crashing on clean up after WINBINDD_PRIV_PIPE_DIR call failed
479 * as interface version (from the first request) returned as a fstring,
480 * thus response.extra_data.data will not be NULL even though
481 * winbindd response did not write over it due to a failure */
482 ZERO_STRUCT(response);
483 if (winbindd_request_response(ctx, WINBINDD_PRIV_PIPE_DIR, &request,
484 &response) == NSS_STATUS_SUCCESS) {
486 fd = winbind_named_pipe_sock((char *)response.extra_data.data);
488 close(ctx->winbindd_fd);
489 ctx->winbindd_fd = fd;
490 ctx->is_privileged = true;
493 SAFE_FREE(response.extra_data.data);
496 if (!ctx->is_privileged) {
500 return ctx->winbindd_fd;
503 #endif /* HAVE_UNIXSOCKET */
506 /* Write data to winbindd socket */
508 static int winbind_write_sock(struct winbindd_context *ctx, void *buffer,
509 int count, int recursing, int need_priv)
511 int fd, result, nwritten;
513 /* Open connection to winbind daemon */
517 fd = winbind_open_pipe_sock(ctx, recursing, need_priv);
523 /* Write data to socket */
527 while(nwritten < count) {
531 /* Catch pipe close on other end by checking if a read()
532 call would not block by calling poll(). */
535 pfd.events = POLLIN|POLLOUT|POLLHUP;
537 ret = poll(&pfd, 1, -1);
539 winbind_close_sock(ctx);
540 return -1; /* poll error */
543 /* Write should be OK if fd not available for reading */
545 if ((ret == 1) && (pfd.revents & (POLLIN|POLLHUP|POLLERR))) {
547 /* Pipe has closed on remote end */
549 winbind_close_sock(ctx);
555 result = write(fd, (char *)buffer + nwritten,
558 if ((result == -1) || (result == 0)) {
562 winbind_close_sock(ctx);
572 /* Read data from winbindd socket */
574 static int winbind_read_sock(struct winbindd_context *ctx,
575 void *buffer, int count)
581 fd = winbind_open_pipe_sock(ctx, false, false);
586 /* Read data from socket */
587 while(nread < count) {
591 /* Catch pipe close on other end by checking if a read()
592 call would not block by calling poll(). */
595 pfd.events = POLLIN|POLLHUP;
597 /* Wait for 5 seconds for a reply. May need to parameterise this... */
599 ret = poll(&pfd, 1, 5000);
601 winbind_close_sock(ctx);
602 return -1; /* poll error */
606 /* Not ready for read yet... */
607 if (total_time >= 300) {
609 winbind_close_sock(ctx);
616 if ((ret == 1) && (pfd.revents & (POLLIN|POLLHUP|POLLERR))) {
620 int result = read(fd, (char *)buffer + nread,
623 if ((result == -1) || (result == 0)) {
625 /* Read failed. I think the only useful thing we
626 can do here is just return -1 and fail since the
627 transaction has failed half way through. */
629 winbind_close_sock(ctx);
643 static int winbindd_read_reply(struct winbindd_context *ctx,
644 struct winbindd_response *response)
646 int result1, result2 = 0;
652 /* Read fixed length response */
654 result1 = winbind_read_sock(ctx, response,
655 sizeof(struct winbindd_response));
657 /* We actually send the pointer value of the extra_data field from
658 the server. This has no meaning in the client's address space
659 so we clear it out. */
661 response->extra_data.data = NULL;
667 if (response->length < sizeof(struct winbindd_response)) {
671 /* Read variable length response */
673 if (response->length > sizeof(struct winbindd_response)) {
674 int extra_data_len = response->length -
675 sizeof(struct winbindd_response);
677 /* Mallocate memory for extra data */
679 if (!(response->extra_data.data = malloc(extra_data_len))) {
683 result2 = winbind_read_sock(ctx, response->extra_data.data,
686 winbindd_free_response(response);
691 /* Return total amount of data read */
693 return result1 + result2;
697 * send simple types of requests
700 static NSS_STATUS winbindd_send_request(
701 struct winbindd_context *ctx,
704 struct winbindd_request *request)
706 struct winbindd_request lrequest;
708 /* Check for our tricky environment variable */
710 if (winbind_env_set()) {
711 return NSS_STATUS_NOTFOUND;
715 ZERO_STRUCT(lrequest);
719 /* Fill in request and send down pipe */
721 winbindd_init_request(request, req_type);
723 if (winbind_write_sock(ctx, request, sizeof(*request),
724 request->wb_flags & WBFLAG_RECURSE,
727 /* Set ENOENT for consistency. Required by some apps */
730 return NSS_STATUS_UNAVAIL;
733 if ((request->extra_len != 0) &&
734 (winbind_write_sock(ctx, request->extra_data.data,
736 request->wb_flags & WBFLAG_RECURSE,
739 /* Set ENOENT for consistency. Required by some apps */
742 return NSS_STATUS_UNAVAIL;
745 return NSS_STATUS_SUCCESS;
749 * Get results from winbindd request
752 static NSS_STATUS winbindd_get_response(struct winbindd_context *ctx,
753 struct winbindd_response *response)
755 struct winbindd_response lresponse;
758 ZERO_STRUCT(lresponse);
759 response = &lresponse;
762 init_response(response);
765 if (winbindd_read_reply(ctx, response) == -1) {
766 /* Set ENOENT for consistency. Required by some apps */
769 return NSS_STATUS_UNAVAIL;
772 /* Throw away extra data if client didn't request it */
773 if (response == &lresponse) {
774 winbindd_free_response(response);
777 /* Copy reply data from socket */
778 if (response->result != WINBINDD_OK) {
779 return NSS_STATUS_NOTFOUND;
782 return NSS_STATUS_SUCCESS;
785 /* Handle simple types of requests */
787 NSS_STATUS winbindd_request_response(struct winbindd_context *ctx,
789 struct winbindd_request *request,
790 struct winbindd_response *response)
792 NSS_STATUS status = NSS_STATUS_UNAVAIL;
793 bool release_global_ctx = false;
796 ctx = get_wb_global_ctx();
797 release_global_ctx = true;
800 status = winbindd_send_request(ctx, req_type, 0, request);
801 if (status != NSS_STATUS_SUCCESS) {
804 status = winbindd_get_response(ctx, response);
807 if (release_global_ctx) {
813 NSS_STATUS winbindd_priv_request_response(struct winbindd_context *ctx,
815 struct winbindd_request *request,
816 struct winbindd_response *response)
818 NSS_STATUS status = NSS_STATUS_UNAVAIL;
819 bool release_global_ctx = false;
822 ctx = get_wb_global_ctx();
823 release_global_ctx = true;
826 status = winbindd_send_request(ctx, req_type, 1, request);
827 if (status != NSS_STATUS_SUCCESS) {
830 status = winbindd_get_response(ctx, response);
833 if (release_global_ctx) {
839 /* Create and free winbindd context */
841 struct winbindd_context *winbindd_ctx_create(void)
843 struct winbindd_context *ctx;
845 ctx = calloc(1, sizeof(struct winbindd_context));
851 ctx->winbindd_fd = -1;
856 void winbindd_ctx_free(struct winbindd_context *ctx)
858 winbind_close_sock(ctx);