lib: Add before/after hooks to async_connect
[kai/samba-autobuild/.git] / source3 / lib / util_sock.c
1 /*
2    Unix SMB/CIFS implementation.
3    Samba utility functions
4    Copyright (C) Andrew Tridgell 1992-1998
5    Copyright (C) Tim Potter      2000-2001
6    Copyright (C) Jeremy Allison  1992-2007
7
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
20 */
21
22 #include "includes.h"
23 #include "system/filesys.h"
24 #include "memcache.h"
25 #include "../lib/async_req/async_sock.h"
26 #include "../lib/util/select.h"
27 #include "lib/socket/interfaces.h"
28 #include "../lib/util/tevent_unix.h"
29 #include "../lib/util/tevent_ntstatus.h"
30 #include "../lib/tsocket/tsocket.h"
31
32 const char *client_name(int fd)
33 {
34         return get_peer_name(fd,false);
35 }
36
37 const char *client_addr(int fd, char *addr, size_t addrlen)
38 {
39         return get_peer_addr(fd,addr,addrlen);
40 }
41
42 #if 0
43 /* Not currently used. JRA. */
44 int client_socket_port(int fd)
45 {
46         return get_socket_port(fd);
47 }
48 #endif
49
50 /****************************************************************************
51  Determine if a file descriptor is in fact a socket.
52 ****************************************************************************/
53
54 bool is_a_socket(int fd)
55 {
56         int v;
57         socklen_t l;
58         l = sizeof(int);
59         return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0);
60 }
61
62 /****************************************************************************
63  Read from a socket.
64 ****************************************************************************/
65
66 ssize_t read_udp_v4_socket(int fd,
67                         char *buf,
68                         size_t len,
69                         struct sockaddr_storage *psa)
70 {
71         ssize_t ret;
72         socklen_t socklen = sizeof(*psa);
73         struct sockaddr_in *si = (struct sockaddr_in *)psa;
74
75         memset((char *)psa,'\0',socklen);
76
77         ret = (ssize_t)sys_recvfrom(fd,buf,len,0,
78                         (struct sockaddr *)psa,&socklen);
79         if (ret <= 0) {
80                 /* Don't print a low debug error for a non-blocking socket. */
81                 if (errno == EAGAIN) {
82                         DEBUG(10,("read_udp_v4_socket: returned EAGAIN\n"));
83                 } else {
84                         DEBUG(2,("read_udp_v4_socket: failed. errno=%s\n",
85                                 strerror(errno)));
86                 }
87                 return 0;
88         }
89
90         if (psa->ss_family != AF_INET) {
91                 DEBUG(2,("read_udp_v4_socket: invalid address family %d "
92                         "(not IPv4)\n", (int)psa->ss_family));
93                 return 0;
94         }
95
96         DEBUG(10,("read_udp_v4_socket: ip %s port %d read: %lu\n",
97                         inet_ntoa(si->sin_addr),
98                         si->sin_port,
99                         (unsigned long)ret));
100
101         return ret;
102 }
103
104 /****************************************************************************
105  Read data from a file descriptor with a timout in msec.
106  mincount = if timeout, minimum to read before returning
107  maxcount = number to be read.
108  time_out = timeout in milliseconds
109  NB. This can be called with a non-socket fd, don't change
110  sys_read() to sys_recv() or other socket call.
111 ****************************************************************************/
112
113 NTSTATUS read_fd_with_timeout(int fd, char *buf,
114                                   size_t mincnt, size_t maxcnt,
115                                   unsigned int time_out,
116                                   size_t *size_ret)
117 {
118         int pollrtn;
119         ssize_t readret;
120         size_t nread = 0;
121
122         /* just checking .... */
123         if (maxcnt <= 0)
124                 return NT_STATUS_OK;
125
126         /* Blocking read */
127         if (time_out == 0) {
128                 if (mincnt == 0) {
129                         mincnt = maxcnt;
130                 }
131
132                 while (nread < mincnt) {
133                         readret = sys_read(fd, buf + nread, maxcnt - nread);
134
135                         if (readret == 0) {
136                                 DEBUG(5,("read_fd_with_timeout: "
137                                         "blocking read. EOF from client.\n"));
138                                 return NT_STATUS_END_OF_FILE;
139                         }
140
141                         if (readret == -1) {
142                                 return map_nt_error_from_unix(errno);
143                         }
144                         nread += readret;
145                 }
146                 goto done;
147         }
148
149         /* Most difficult - timeout read */
150         /* If this is ever called on a disk file and
151            mincnt is greater then the filesize then
152            system performance will suffer severely as
153            select always returns true on disk files */
154
155         for (nread=0; nread < mincnt; ) {
156                 int revents;
157
158                 pollrtn = poll_intr_one_fd(fd, POLLIN|POLLHUP, time_out,
159                                            &revents);
160
161                 /* Check if error */
162                 if (pollrtn == -1) {
163                         return map_nt_error_from_unix(errno);
164                 }
165
166                 /* Did we timeout ? */
167                 if ((pollrtn == 0) ||
168                     ((revents & (POLLIN|POLLHUP|POLLERR)) == 0)) {
169                         DEBUG(10,("read_fd_with_timeout: timeout read. "
170                                 "select timed out.\n"));
171                         return NT_STATUS_IO_TIMEOUT;
172                 }
173
174                 readret = sys_read(fd, buf+nread, maxcnt-nread);
175
176                 if (readret == 0) {
177                         /* we got EOF on the file descriptor */
178                         DEBUG(5,("read_fd_with_timeout: timeout read. "
179                                 "EOF from client.\n"));
180                         return NT_STATUS_END_OF_FILE;
181                 }
182
183                 if (readret == -1) {
184                         return map_nt_error_from_unix(errno);
185                 }
186
187                 nread += readret;
188         }
189
190  done:
191         /* Return the number we got */
192         if (size_ret) {
193                 *size_ret = nread;
194         }
195         return NT_STATUS_OK;
196 }
197
198 /****************************************************************************
199  Read data from an fd, reading exactly N bytes.
200  NB. This can be called with a non-socket fd, don't add dependencies
201  on socket calls.
202 ****************************************************************************/
203
204 NTSTATUS read_data(int fd, char *buffer, size_t N)
205 {
206         return read_fd_with_timeout(fd, buffer, N, N, 0, NULL);
207 }
208
209 /****************************************************************************
210  Write all data from an iov array
211  NB. This can be called with a non-socket fd, don't add dependencies
212  on socket calls.
213 ****************************************************************************/
214
215 ssize_t write_data_iov(int fd, const struct iovec *orig_iov, int iovcnt)
216 {
217         int i;
218         size_t to_send;
219         ssize_t thistime;
220         size_t sent;
221         struct iovec *iov_copy, *iov;
222
223         to_send = 0;
224         for (i=0; i<iovcnt; i++) {
225                 to_send += orig_iov[i].iov_len;
226         }
227
228         thistime = sys_writev(fd, orig_iov, iovcnt);
229         if ((thistime <= 0) || (thistime == to_send)) {
230                 return thistime;
231         }
232         sent = thistime;
233
234         /*
235          * We could not send everything in one call. Make a copy of iov that
236          * we can mess with. We keep a copy of the array start in iov_copy for
237          * the TALLOC_FREE, because we're going to modify iov later on,
238          * discarding elements.
239          */
240
241         iov_copy = (struct iovec *)talloc_memdup(
242                 talloc_tos(), orig_iov, sizeof(struct iovec) * iovcnt);
243
244         if (iov_copy == NULL) {
245                 errno = ENOMEM;
246                 return -1;
247         }
248         iov = iov_copy;
249
250         while (sent < to_send) {
251                 /*
252                  * We have to discard "thistime" bytes from the beginning
253                  * iov array, "thistime" contains the number of bytes sent
254                  * via writev last.
255                  */
256                 while (thistime > 0) {
257                         if (thistime < iov[0].iov_len) {
258                                 char *new_base =
259                                         (char *)iov[0].iov_base + thistime;
260                                 iov[0].iov_base = (void *)new_base;
261                                 iov[0].iov_len -= thistime;
262                                 break;
263                         }
264                         thistime -= iov[0].iov_len;
265                         iov += 1;
266                         iovcnt -= 1;
267                 }
268
269                 thistime = sys_writev(fd, iov, iovcnt);
270                 if (thistime <= 0) {
271                         break;
272                 }
273                 sent += thistime;
274         }
275
276         TALLOC_FREE(iov_copy);
277         return sent;
278 }
279
280 /****************************************************************************
281  Write data to a fd.
282  NB. This can be called with a non-socket fd, don't add dependencies
283  on socket calls.
284 ****************************************************************************/
285
286 ssize_t write_data(int fd, const char *buffer, size_t N)
287 {
288         struct iovec iov;
289
290         iov.iov_base = discard_const_p(void, buffer);
291         iov.iov_len = N;
292         return write_data_iov(fd, &iov, 1);
293 }
294
295 /****************************************************************************
296  Send a keepalive packet (rfc1002).
297 ****************************************************************************/
298
299 bool send_keepalive(int client)
300 {
301         unsigned char buf[4];
302
303         buf[0] = NBSSkeepalive;
304         buf[1] = buf[2] = buf[3] = 0;
305
306         return(write_data(client,(char *)buf,4) == 4);
307 }
308
309 /****************************************************************************
310  Read 4 bytes of a smb packet and return the smb length of the packet.
311  Store the result in the buffer.
312  This version of the function will return a length of zero on receiving
313  a keepalive packet.
314  Timeout is in milliseconds.
315 ****************************************************************************/
316
317 NTSTATUS read_smb_length_return_keepalive(int fd, char *inbuf,
318                                           unsigned int timeout,
319                                           size_t *len)
320 {
321         int msg_type;
322         NTSTATUS status;
323
324         status = read_fd_with_timeout(fd, inbuf, 4, 4, timeout, NULL);
325
326         if (!NT_STATUS_IS_OK(status)) {
327                 return status;
328         }
329
330         *len = smb_len(inbuf);
331         msg_type = CVAL(inbuf,0);
332
333         if (msg_type == NBSSkeepalive) {
334                 DEBUG(5,("Got keepalive packet\n"));
335         }
336
337         DEBUG(10,("got smb length of %lu\n",(unsigned long)(*len)));
338
339         return NT_STATUS_OK;
340 }
341
342 /****************************************************************************
343  Read an smb from a fd.
344  The timeout is in milliseconds.
345  This function will return on receipt of a session keepalive packet.
346  maxlen is the max number of bytes to return, not including the 4 byte
347  length. If zero it means buflen limit.
348  Doesn't check the MAC on signed packets.
349 ****************************************************************************/
350
351 NTSTATUS receive_smb_raw(int fd, char *buffer, size_t buflen, unsigned int timeout,
352                          size_t maxlen, size_t *p_len)
353 {
354         size_t len;
355         NTSTATUS status;
356
357         status = read_smb_length_return_keepalive(fd,buffer,timeout,&len);
358
359         if (!NT_STATUS_IS_OK(status)) {
360                 DEBUG(0, ("read_fd_with_timeout failed, read "
361                           "error = %s.\n", nt_errstr(status)));
362                 return status;
363         }
364
365         if (len > buflen) {
366                 DEBUG(0,("Invalid packet length! (%lu bytes).\n",
367                                         (unsigned long)len));
368                 return NT_STATUS_INVALID_PARAMETER;
369         }
370
371         if(len > 0) {
372                 if (maxlen) {
373                         len = MIN(len,maxlen);
374                 }
375
376                 status = read_fd_with_timeout(
377                         fd, buffer+4, len, len, timeout, &len);
378
379                 if (!NT_STATUS_IS_OK(status)) {
380                         DEBUG(0, ("read_fd_with_timeout failed, read error = "
381                                   "%s.\n", nt_errstr(status)));
382                         return status;
383                 }
384
385                 /* not all of samba3 properly checks for packet-termination
386                  * of strings. This ensures that we don't run off into
387                  * empty space. */
388                 SSVAL(buffer+4,len, 0);
389         }
390
391         *p_len = len;
392         return NT_STATUS_OK;
393 }
394
395 /****************************************************************************
396  Open a socket of the specified type, port, and address for incoming data.
397 ****************************************************************************/
398
399 int open_socket_in(int type,
400                 uint16_t port,
401                 int dlevel,
402                 const struct sockaddr_storage *psock,
403                 bool rebind)
404 {
405         struct sockaddr_storage sock;
406         int res;
407         socklen_t slen = sizeof(struct sockaddr_in);
408
409         sock = *psock;
410
411 #if defined(HAVE_IPV6)
412         if (sock.ss_family == AF_INET6) {
413                 ((struct sockaddr_in6 *)&sock)->sin6_port = htons(port);
414                 slen = sizeof(struct sockaddr_in6);
415         }
416 #endif
417         if (sock.ss_family == AF_INET) {
418                 ((struct sockaddr_in *)&sock)->sin_port = htons(port);
419         }
420
421         res = socket(sock.ss_family, type, 0 );
422         if( res == -1 ) {
423                 if( DEBUGLVL(0) ) {
424                         dbgtext( "open_socket_in(): socket() call failed: " );
425                         dbgtext( "%s\n", strerror( errno ) );
426                 }
427                 return -1;
428         }
429
430         /* This block sets/clears the SO_REUSEADDR and possibly SO_REUSEPORT. */
431         {
432                 int val = rebind ? 1 : 0;
433                 if( setsockopt(res,SOL_SOCKET,SO_REUSEADDR,
434                                         (char *)&val,sizeof(val)) == -1 ) {
435                         if( DEBUGLVL( dlevel ) ) {
436                                 dbgtext( "open_socket_in(): setsockopt: " );
437                                 dbgtext( "SO_REUSEADDR = %s ",
438                                                 val?"true":"false" );
439                                 dbgtext( "on port %d failed ", port );
440                                 dbgtext( "with error = %s\n", strerror(errno) );
441                         }
442                 }
443 #ifdef SO_REUSEPORT
444                 if( setsockopt(res,SOL_SOCKET,SO_REUSEPORT,
445                                         (char *)&val,sizeof(val)) == -1 ) {
446                         if( DEBUGLVL( dlevel ) ) {
447                                 dbgtext( "open_socket_in(): setsockopt: ");
448                                 dbgtext( "SO_REUSEPORT = %s ",
449                                                 val?"true":"false");
450                                 dbgtext( "on port %d failed ", port);
451                                 dbgtext( "with error = %s\n", strerror(errno));
452                         }
453                 }
454 #endif /* SO_REUSEPORT */
455         }
456
457 #ifdef HAVE_IPV6
458         /*
459          * As IPV6_V6ONLY is the default on some systems,
460          * we better try to be consistent and always use it.
461          *
462          * This also avoids using IPv4 via AF_INET6 sockets
463          * and makes sure %I never resolves to a '::ffff:192.168.0.1'
464          * string.
465          */
466         if (sock.ss_family == AF_INET6) {
467                 int val = 1;
468                 int ret;
469
470                 ret = setsockopt(res, IPPROTO_IPV6, IPV6_V6ONLY,
471                                  (const void *)&val, sizeof(val));
472                 if (ret == -1) {
473                         if(DEBUGLVL(0)) {
474                                 dbgtext("open_socket_in(): IPV6_ONLY failed: ");
475                                 dbgtext("%s\n", strerror(errno));
476                         }
477                         close(res);
478                         return -1;
479                 }
480         }
481 #endif
482
483         /* now we've got a socket - we need to bind it */
484         if (bind(res, (struct sockaddr *)&sock, slen) == -1 ) {
485                 if( DEBUGLVL(dlevel) && (port == NMB_PORT ||
486                                          port == NBT_SMB_PORT ||
487                                          port == TCP_SMB_PORT) ) {
488                         char addr[INET6_ADDRSTRLEN];
489                         print_sockaddr(addr, sizeof(addr),
490                                         &sock);
491                         dbgtext( "bind failed on port %d ", port);
492                         dbgtext( "socket_addr = %s.\n", addr);
493                         dbgtext( "Error = %s\n", strerror(errno));
494                 }
495                 close(res);
496                 return -1;
497         }
498
499         DEBUG( 10, ( "bind succeeded on port %d\n", port ) );
500         return( res );
501  }
502
503 struct open_socket_out_state {
504         int fd;
505         struct tevent_context *ev;
506         struct sockaddr_storage ss;
507         socklen_t salen;
508         uint16_t port;
509         int wait_usec;
510 };
511
512 static void open_socket_out_connected(struct tevent_req *subreq);
513
514 static int open_socket_out_state_destructor(struct open_socket_out_state *s)
515 {
516         if (s->fd != -1) {
517                 close(s->fd);
518         }
519         return 0;
520 }
521
522 /****************************************************************************
523  Create an outgoing socket. timeout is in milliseconds.
524 **************************************************************************/
525
526 struct tevent_req *open_socket_out_send(TALLOC_CTX *mem_ctx,
527                                         struct tevent_context *ev,
528                                         const struct sockaddr_storage *pss,
529                                         uint16_t port,
530                                         int timeout)
531 {
532         char addr[INET6_ADDRSTRLEN];
533         struct tevent_req *result, *subreq;
534         struct open_socket_out_state *state;
535         NTSTATUS status;
536
537         result = tevent_req_create(mem_ctx, &state,
538                                    struct open_socket_out_state);
539         if (result == NULL) {
540                 return NULL;
541         }
542         state->ev = ev;
543         state->ss = *pss;
544         state->port = port;
545         state->wait_usec = 10000;
546         state->salen = -1;
547
548         state->fd = socket(state->ss.ss_family, SOCK_STREAM, 0);
549         if (state->fd == -1) {
550                 status = map_nt_error_from_unix(errno);
551                 goto post_status;
552         }
553         talloc_set_destructor(state, open_socket_out_state_destructor);
554
555         if (!tevent_req_set_endtime(
556                     result, ev, timeval_current_ofs_msec(timeout))) {
557                 goto fail;
558         }
559
560 #if defined(HAVE_IPV6)
561         if (pss->ss_family == AF_INET6) {
562                 struct sockaddr_in6 *psa6;
563                 psa6 = (struct sockaddr_in6 *)&state->ss;
564                 psa6->sin6_port = htons(port);
565                 if (psa6->sin6_scope_id == 0
566                     && IN6_IS_ADDR_LINKLOCAL(&psa6->sin6_addr)) {
567                         setup_linklocal_scope_id(
568                                 (struct sockaddr *)&(state->ss));
569                 }
570                 state->salen = sizeof(struct sockaddr_in6);
571         }
572 #endif
573         if (pss->ss_family == AF_INET) {
574                 struct sockaddr_in *psa;
575                 psa = (struct sockaddr_in *)&state->ss;
576                 psa->sin_port = htons(port);
577                 state->salen = sizeof(struct sockaddr_in);
578         }
579
580         if (pss->ss_family == AF_UNIX) {
581                 state->salen = sizeof(struct sockaddr_un);
582         }
583
584         print_sockaddr(addr, sizeof(addr), &state->ss);
585         DEBUG(3,("Connecting to %s at port %u\n", addr, (unsigned int)port));
586
587         subreq = async_connect_send(state, state->ev, state->fd,
588                                     (struct sockaddr *)&state->ss,
589                                     state->salen, NULL, NULL, NULL);
590         if ((subreq == NULL)
591             || !tevent_req_set_endtime(
592                     subreq, state->ev,
593                     timeval_current_ofs(0, state->wait_usec))) {
594                 goto fail;
595         }
596         tevent_req_set_callback(subreq, open_socket_out_connected, result);
597         return result;
598
599  post_status:
600         tevent_req_nterror(result, status);
601         return tevent_req_post(result, ev);
602  fail:
603         TALLOC_FREE(result);
604         return NULL;
605 }
606
607 static void open_socket_out_connected(struct tevent_req *subreq)
608 {
609         struct tevent_req *req =
610                 tevent_req_callback_data(subreq, struct tevent_req);
611         struct open_socket_out_state *state =
612                 tevent_req_data(req, struct open_socket_out_state);
613         int ret;
614         int sys_errno;
615
616         ret = async_connect_recv(subreq, &sys_errno);
617         TALLOC_FREE(subreq);
618         if (ret == 0) {
619                 tevent_req_done(req);
620                 return;
621         }
622
623         if (
624 #ifdef ETIMEDOUT
625                 (sys_errno == ETIMEDOUT) ||
626 #endif
627                 (sys_errno == EINPROGRESS) ||
628                 (sys_errno == EALREADY) ||
629                 (sys_errno == EAGAIN)) {
630
631                 /*
632                  * retry
633                  */
634
635                 if (state->wait_usec < 250000) {
636                         state->wait_usec *= 1.5;
637                 }
638
639                 subreq = async_connect_send(state, state->ev, state->fd,
640                                             (struct sockaddr *)&state->ss,
641                                             state->salen, NULL, NULL, NULL);
642                 if (tevent_req_nomem(subreq, req)) {
643                         return;
644                 }
645                 if (!tevent_req_set_endtime(
646                             subreq, state->ev,
647                             timeval_current_ofs_usec(state->wait_usec))) {
648                         tevent_req_nterror(req, NT_STATUS_NO_MEMORY);
649                         return;
650                 }
651                 tevent_req_set_callback(subreq, open_socket_out_connected, req);
652                 return;
653         }
654
655 #ifdef EISCONN
656         if (sys_errno == EISCONN) {
657                 tevent_req_done(req);
658                 return;
659         }
660 #endif
661
662         /* real error */
663         tevent_req_nterror(req, map_nt_error_from_unix(sys_errno));
664 }
665
666 NTSTATUS open_socket_out_recv(struct tevent_req *req, int *pfd)
667 {
668         struct open_socket_out_state *state =
669                 tevent_req_data(req, struct open_socket_out_state);
670         NTSTATUS status;
671
672         if (tevent_req_is_nterror(req, &status)) {
673                 return status;
674         }
675         *pfd = state->fd;
676         state->fd = -1;
677         return NT_STATUS_OK;
678 }
679
680 /**
681 * @brief open a socket
682 *
683 * @param pss a struct sockaddr_storage defining the address to connect to
684 * @param port to connect to
685 * @param timeout in MILLISECONDS
686 * @param pfd file descriptor returned
687 *
688 * @return NTSTATUS code
689 */
690 NTSTATUS open_socket_out(const struct sockaddr_storage *pss, uint16_t port,
691                          int timeout, int *pfd)
692 {
693         TALLOC_CTX *frame = talloc_stackframe();
694         struct tevent_context *ev;
695         struct tevent_req *req;
696         NTSTATUS status = NT_STATUS_NO_MEMORY;
697
698         ev = samba_tevent_context_init(frame);
699         if (ev == NULL) {
700                 goto fail;
701         }
702
703         req = open_socket_out_send(frame, ev, pss, port, timeout);
704         if (req == NULL) {
705                 goto fail;
706         }
707         if (!tevent_req_poll(req, ev)) {
708                 status = NT_STATUS_INTERNAL_ERROR;
709                 goto fail;
710         }
711         status = open_socket_out_recv(req, pfd);
712  fail:
713         TALLOC_FREE(frame);
714         return status;
715 }
716
717 struct open_socket_out_defer_state {
718         struct tevent_context *ev;
719         struct sockaddr_storage ss;
720         uint16_t port;
721         int timeout;
722         int fd;
723 };
724
725 static void open_socket_out_defer_waited(struct tevent_req *subreq);
726 static void open_socket_out_defer_connected(struct tevent_req *subreq);
727
728 struct tevent_req *open_socket_out_defer_send(TALLOC_CTX *mem_ctx,
729                                               struct tevent_context *ev,
730                                               struct timeval wait_time,
731                                               const struct sockaddr_storage *pss,
732                                               uint16_t port,
733                                               int timeout)
734 {
735         struct tevent_req *req, *subreq;
736         struct open_socket_out_defer_state *state;
737
738         req = tevent_req_create(mem_ctx, &state,
739                                 struct open_socket_out_defer_state);
740         if (req == NULL) {
741                 return NULL;
742         }
743         state->ev = ev;
744         state->ss = *pss;
745         state->port = port;
746         state->timeout = timeout;
747
748         subreq = tevent_wakeup_send(
749                 state, ev,
750                 timeval_current_ofs(wait_time.tv_sec, wait_time.tv_usec));
751         if (subreq == NULL) {
752                 goto fail;
753         }
754         tevent_req_set_callback(subreq, open_socket_out_defer_waited, req);
755         return req;
756  fail:
757         TALLOC_FREE(req);
758         return NULL;
759 }
760
761 static void open_socket_out_defer_waited(struct tevent_req *subreq)
762 {
763         struct tevent_req *req = tevent_req_callback_data(
764                 subreq, struct tevent_req);
765         struct open_socket_out_defer_state *state = tevent_req_data(
766                 req, struct open_socket_out_defer_state);
767         bool ret;
768
769         ret = tevent_wakeup_recv(subreq);
770         TALLOC_FREE(subreq);
771         if (!ret) {
772                 tevent_req_nterror(req, NT_STATUS_INTERNAL_ERROR);
773                 return;
774         }
775
776         subreq = open_socket_out_send(state, state->ev, &state->ss,
777                                       state->port, state->timeout);
778         if (tevent_req_nomem(subreq, req)) {
779                 return;
780         }
781         tevent_req_set_callback(subreq, open_socket_out_defer_connected, req);
782 }
783
784 static void open_socket_out_defer_connected(struct tevent_req *subreq)
785 {
786         struct tevent_req *req = tevent_req_callback_data(
787                 subreq, struct tevent_req);
788         struct open_socket_out_defer_state *state = tevent_req_data(
789                 req, struct open_socket_out_defer_state);
790         NTSTATUS status;
791
792         status = open_socket_out_recv(subreq, &state->fd);
793         TALLOC_FREE(subreq);
794         if (!NT_STATUS_IS_OK(status)) {
795                 tevent_req_nterror(req, status);
796                 return;
797         }
798         tevent_req_done(req);
799 }
800
801 NTSTATUS open_socket_out_defer_recv(struct tevent_req *req, int *pfd)
802 {
803         struct open_socket_out_defer_state *state = tevent_req_data(
804                 req, struct open_socket_out_defer_state);
805         NTSTATUS status;
806
807         if (tevent_req_is_nterror(req, &status)) {
808                 return status;
809         }
810         *pfd = state->fd;
811         state->fd = -1;
812         return NT_STATUS_OK;
813 }
814
815 /****************************************************************************
816  Open a connected UDP socket to host on port
817 **************************************************************************/
818
819 int open_udp_socket(const char *host, int port)
820 {
821         struct sockaddr_storage ss;
822         int res;
823         socklen_t salen;
824
825         if (!interpret_string_addr(&ss, host, 0)) {
826                 DEBUG(10,("open_udp_socket: can't resolve name %s\n",
827                         host));
828                 return -1;
829         }
830
831         res = socket(ss.ss_family, SOCK_DGRAM, 0);
832         if (res == -1) {
833                 return -1;
834         }
835
836 #if defined(HAVE_IPV6)
837         if (ss.ss_family == AF_INET6) {
838                 struct sockaddr_in6 *psa6;
839                 psa6 = (struct sockaddr_in6 *)&ss;
840                 psa6->sin6_port = htons(port);
841                 if (psa6->sin6_scope_id == 0
842                                 && IN6_IS_ADDR_LINKLOCAL(&psa6->sin6_addr)) {
843                         setup_linklocal_scope_id(
844                                 (struct sockaddr *)&ss);
845                 }
846                 salen = sizeof(struct sockaddr_in6);
847         } else 
848 #endif
849         if (ss.ss_family == AF_INET) {
850                 struct sockaddr_in *psa;
851                 psa = (struct sockaddr_in *)&ss;
852                 psa->sin_port = htons(port);
853             salen = sizeof(struct sockaddr_in);
854         } else {
855                 DEBUG(1, ("unknown socket family %d", ss.ss_family));
856                 close(res);
857                 return -1;
858         }
859
860         if (connect(res, (struct sockaddr *)&ss, salen)) {
861                 close(res);
862                 return -1;
863         }
864
865         return res;
866 }
867
868 /*******************************************************************
869  Return the IP addr of the remote end of a socket as a string.
870  Optionally return the struct sockaddr_storage.
871  ******************************************************************/
872
873 static const char *get_peer_addr_internal(int fd,
874                                 char *addr_buf,
875                                 size_t addr_buf_len,
876                                 struct sockaddr *pss,
877                                 socklen_t *plength)
878 {
879         struct sockaddr_storage ss;
880         socklen_t length = sizeof(ss);
881
882         strlcpy(addr_buf,"0.0.0.0",addr_buf_len);
883
884         if (fd == -1) {
885                 return addr_buf;
886         }
887
888         if (pss == NULL) {
889                 pss = (struct sockaddr *)&ss;
890                 plength = &length;
891         }
892
893         if (getpeername(fd, (struct sockaddr *)pss, plength) < 0) {
894                 int level = (errno == ENOTCONN) ? 2 : 0;
895                 DEBUG(level, ("getpeername failed. Error was %s\n",
896                                strerror(errno)));
897                 return addr_buf;
898         }
899
900         print_sockaddr_len(addr_buf,
901                         addr_buf_len,
902                         pss,
903                         *plength);
904         return addr_buf;
905 }
906
907 /*******************************************************************
908  Matchname - determine if host name matches IP address. Used to
909  confirm a hostname lookup to prevent spoof attacks.
910 ******************************************************************/
911
912 static bool matchname(const char *remotehost,
913                 const struct sockaddr *pss,
914                 socklen_t len)
915 {
916         struct addrinfo *res = NULL;
917         struct addrinfo *ailist = NULL;
918         char addr_buf[INET6_ADDRSTRLEN];
919         bool ret = interpret_string_addr_internal(&ailist,
920                         remotehost,
921                         AI_ADDRCONFIG|AI_CANONNAME);
922
923         if (!ret || ailist == NULL) {
924                 DEBUG(3,("matchname: getaddrinfo failed for "
925                         "name %s [%s]\n",
926                         remotehost,
927                         gai_strerror(ret) ));
928                 return false;
929         }
930
931         /*
932          * Make sure that getaddrinfo() returns the "correct" host name.
933          */
934
935         if (ailist->ai_canonname == NULL ||
936                 (!strequal(remotehost, ailist->ai_canonname) &&
937                  !strequal(remotehost, "localhost"))) {
938                 DEBUG(0,("matchname: host name/name mismatch: %s != %s\n",
939                          remotehost,
940                          ailist->ai_canonname ?
941                                  ailist->ai_canonname : "(NULL)"));
942                 freeaddrinfo(ailist);
943                 return false;
944         }
945
946         /* Look up the host address in the address list we just got. */
947         for (res = ailist; res; res = res->ai_next) {
948                 if (!res->ai_addr) {
949                         continue;
950                 }
951                 if (sockaddr_equal((const struct sockaddr *)res->ai_addr,
952                                         (const struct sockaddr *)pss)) {
953                         freeaddrinfo(ailist);
954                         return true;
955                 }
956         }
957
958         /*
959          * The host name does not map to the original host address. Perhaps
960          * someone has compromised a name server. More likely someone botched
961          * it, but that could be dangerous, too.
962          */
963
964         DEBUG(0,("matchname: host name/address mismatch: %s != %s\n",
965                 print_sockaddr_len(addr_buf,
966                         sizeof(addr_buf),
967                         pss,
968                         len),
969                  ailist->ai_canonname ? ailist->ai_canonname : "(NULL)"));
970
971         if (ailist) {
972                 freeaddrinfo(ailist);
973         }
974         return false;
975 }
976
977 /*******************************************************************
978  Deal with the singleton cache.
979 ******************************************************************/
980
981 struct name_addr_pair {
982         struct sockaddr_storage ss;
983         const char *name;
984 };
985
986 /*******************************************************************
987  Lookup a name/addr pair. Returns memory allocated from memcache.
988 ******************************************************************/
989
990 static bool lookup_nc(struct name_addr_pair *nc)
991 {
992         DATA_BLOB tmp;
993
994         ZERO_STRUCTP(nc);
995
996         if (!memcache_lookup(
997                         NULL, SINGLETON_CACHE,
998                         data_blob_string_const_null("get_peer_name"),
999                         &tmp)) {
1000                 return false;
1001         }
1002
1003         memcpy(&nc->ss, tmp.data, sizeof(nc->ss));
1004         nc->name = (const char *)tmp.data + sizeof(nc->ss);
1005         return true;
1006 }
1007
1008 /*******************************************************************
1009  Save a name/addr pair.
1010 ******************************************************************/
1011
1012 static void store_nc(const struct name_addr_pair *nc)
1013 {
1014         DATA_BLOB tmp;
1015         size_t namelen = strlen(nc->name);
1016
1017         tmp = data_blob(NULL, sizeof(nc->ss) + namelen + 1);
1018         if (!tmp.data) {
1019                 return;
1020         }
1021         memcpy(tmp.data, &nc->ss, sizeof(nc->ss));
1022         memcpy(tmp.data+sizeof(nc->ss), nc->name, namelen+1);
1023
1024         memcache_add(NULL, SINGLETON_CACHE,
1025                         data_blob_string_const_null("get_peer_name"),
1026                         tmp);
1027         data_blob_free(&tmp);
1028 }
1029
1030 /*******************************************************************
1031  Return the DNS name of the remote end of a socket.
1032 ******************************************************************/
1033
1034 const char *get_peer_name(int fd, bool force_lookup)
1035 {
1036         struct name_addr_pair nc;
1037         char addr_buf[INET6_ADDRSTRLEN];
1038         struct sockaddr_storage ss;
1039         socklen_t length = sizeof(ss);
1040         const char *p;
1041         int ret;
1042         char name_buf[MAX_DNS_NAME_LENGTH];
1043         char tmp_name[MAX_DNS_NAME_LENGTH];
1044
1045         /* reverse lookups can be *very* expensive, and in many
1046            situations won't work because many networks don't link dhcp
1047            with dns. To avoid the delay we avoid the lookup if
1048            possible */
1049         if (!lp_hostname_lookups() && (force_lookup == false)) {
1050                 length = sizeof(nc.ss);
1051                 nc.name = get_peer_addr_internal(fd, addr_buf, sizeof(addr_buf),
1052                         (struct sockaddr *)&nc.ss, &length);
1053                 store_nc(&nc);
1054                 lookup_nc(&nc);
1055                 return nc.name ? nc.name : "UNKNOWN";
1056         }
1057
1058         lookup_nc(&nc);
1059
1060         memset(&ss, '\0', sizeof(ss));
1061         p = get_peer_addr_internal(fd, addr_buf, sizeof(addr_buf), (struct sockaddr *)&ss, &length);
1062
1063         /* it might be the same as the last one - save some DNS work */
1064         if (sockaddr_equal((struct sockaddr *)&ss, (struct sockaddr *)&nc.ss)) {
1065                 return nc.name ? nc.name : "UNKNOWN";
1066         }
1067
1068         /* Not the same. We need to lookup. */
1069         if (fd == -1) {
1070                 return "UNKNOWN";
1071         }
1072
1073         /* Look up the remote host name. */
1074         ret = sys_getnameinfo((struct sockaddr *)&ss,
1075                         length,
1076                         name_buf,
1077                         sizeof(name_buf),
1078                         NULL,
1079                         0,
1080                         0);
1081
1082         if (ret) {
1083                 DEBUG(1,("get_peer_name: getnameinfo failed "
1084                         "for %s with error %s\n",
1085                         p,
1086                         gai_strerror(ret)));
1087                 strlcpy(name_buf, p, sizeof(name_buf));
1088         } else {
1089                 if (!matchname(name_buf, (struct sockaddr *)&ss, length)) {
1090                         DEBUG(0,("Matchname failed on %s %s\n",name_buf,p));
1091                         strlcpy(name_buf,"UNKNOWN",sizeof(name_buf));
1092                 }
1093         }
1094
1095         strlcpy(tmp_name, name_buf, sizeof(tmp_name));
1096         alpha_strcpy(name_buf, tmp_name, "_-.", sizeof(name_buf));
1097         if (strstr(name_buf,"..")) {
1098                 strlcpy(name_buf, "UNKNOWN", sizeof(name_buf));
1099         }
1100
1101         nc.name = name_buf;
1102         nc.ss = ss;
1103
1104         store_nc(&nc);
1105         lookup_nc(&nc);
1106         return nc.name ? nc.name : "UNKNOWN";
1107 }
1108
1109 /*******************************************************************
1110  Return the IP addr of the remote end of a socket as a string.
1111  ******************************************************************/
1112
1113 const char *get_peer_addr(int fd, char *addr, size_t addr_len)
1114 {
1115         return get_peer_addr_internal(fd, addr, addr_len, NULL, NULL);
1116 }
1117
1118 int get_remote_hostname(const struct tsocket_address *remote_address,
1119                         char **name,
1120                         TALLOC_CTX *mem_ctx)
1121 {
1122         char name_buf[MAX_DNS_NAME_LENGTH];
1123         char tmp_name[MAX_DNS_NAME_LENGTH];
1124         struct name_addr_pair nc;
1125         struct sockaddr_storage ss;
1126         ssize_t len;
1127         int rc;
1128
1129         if (!lp_hostname_lookups()) {
1130                 nc.name = tsocket_address_inet_addr_string(remote_address,
1131                                                            mem_ctx);
1132                 if (nc.name == NULL) {
1133                         return -1;
1134                 }
1135
1136                 len = tsocket_address_bsd_sockaddr(remote_address,
1137                                                    (struct sockaddr *) &nc.ss,
1138                                                    sizeof(struct sockaddr_storage));
1139                 if (len < 0) {
1140                         return -1;
1141                 }
1142
1143                 store_nc(&nc);
1144                 lookup_nc(&nc);
1145
1146                 if (nc.name == NULL) {
1147                         *name = talloc_strdup(mem_ctx, "UNKNOWN");
1148                 } else {
1149                         *name = talloc_strdup(mem_ctx, nc.name);
1150                 }
1151                 return 0;
1152         }
1153
1154         lookup_nc(&nc);
1155
1156         ZERO_STRUCT(ss);
1157
1158         len = tsocket_address_bsd_sockaddr(remote_address,
1159                                            (struct sockaddr *) &ss,
1160                                            sizeof(struct sockaddr_storage));
1161         if (len < 0) {
1162                 return -1;
1163         }
1164
1165         /* it might be the same as the last one - save some DNS work */
1166         if (sockaddr_equal((struct sockaddr *)&ss, (struct sockaddr *)&nc.ss)) {
1167                 if (nc.name == NULL) {
1168                         *name = talloc_strdup(mem_ctx, "UNKNOWN");
1169                 } else {
1170                         *name = talloc_strdup(mem_ctx, nc.name);
1171                 }
1172                 return 0;
1173         }
1174
1175         /* Look up the remote host name. */
1176         rc = sys_getnameinfo((struct sockaddr *) &ss,
1177                              len,
1178                              name_buf,
1179                              sizeof(name_buf),
1180                              NULL,
1181                              0,
1182                              0);
1183         if (rc < 0) {
1184                 char *p;
1185
1186                 p = tsocket_address_inet_addr_string(remote_address, mem_ctx);
1187                 if (p == NULL) {
1188                         return -1;
1189                 }
1190
1191                 DEBUG(1,("getnameinfo failed for %s with error %s\n",
1192                          p,
1193                          gai_strerror(rc)));
1194                 strlcpy(name_buf, p, sizeof(name_buf));
1195
1196                 TALLOC_FREE(p);
1197         } else {
1198                 if (!matchname(name_buf, (struct sockaddr *)&ss, len)) {
1199                         DEBUG(0,("matchname failed on %s\n", name_buf));
1200                         strlcpy(name_buf, "UNKNOWN", sizeof(name_buf));
1201                 }
1202         }
1203
1204         strlcpy(tmp_name, name_buf, sizeof(tmp_name));
1205         alpha_strcpy(name_buf, tmp_name, "_-.", sizeof(name_buf));
1206         if (strstr(name_buf,"..")) {
1207                 strlcpy(name_buf, "UNKNOWN", sizeof(name_buf));
1208         }
1209
1210         nc.name = name_buf;
1211         nc.ss = ss;
1212
1213         store_nc(&nc);
1214         lookup_nc(&nc);
1215
1216         if (nc.name == NULL) {
1217                 *name = talloc_strdup(mem_ctx, "UNKOWN");
1218         } else {
1219                 *name = talloc_strdup(mem_ctx, nc.name);
1220         }
1221
1222         return 0;
1223 }
1224
1225 /*******************************************************************
1226  Create protected unix domain socket.
1227
1228  Some unixes cannot set permissions on a ux-dom-sock, so we
1229  have to make sure that the directory contains the protection
1230  permissions instead.
1231  ******************************************************************/
1232
1233 int create_pipe_sock(const char *socket_dir,
1234                      const char *socket_name,
1235                      mode_t dir_perms)
1236 {
1237 #ifdef HAVE_UNIXSOCKET
1238         struct sockaddr_un sunaddr;
1239         bool ok;
1240         int sock;
1241         char *path = NULL;
1242
1243         ok = directory_create_or_exist_strict(socket_dir,
1244                                               sec_initial_uid(),
1245                                               dir_perms);
1246         if (!ok) {
1247                 return -1;
1248         }
1249
1250         /* Create the socket file */
1251         sock = socket(AF_UNIX, SOCK_STREAM, 0);
1252
1253         if (sock == -1) {
1254                 DEBUG(0, ("create_pipe_sock: socket error %s\n",
1255                         strerror(errno) ));
1256                 goto out_close;
1257         }
1258
1259         if (asprintf(&path, "%s/%s", socket_dir, socket_name) == -1) {
1260                 goto out_close;
1261         }
1262
1263         unlink(path);
1264         memset(&sunaddr, 0, sizeof(sunaddr));
1265         sunaddr.sun_family = AF_UNIX;
1266         strlcpy(sunaddr.sun_path, path, sizeof(sunaddr.sun_path));
1267
1268         if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) == -1) {
1269                 DEBUG(0, ("bind failed on pipe socket %s: %s\n", path,
1270                         strerror(errno)));
1271                 goto out_close;
1272         }
1273
1274         SAFE_FREE(path);
1275
1276         return sock;
1277
1278 out_close:
1279         SAFE_FREE(path);
1280         if (sock != -1)
1281                 close(sock);
1282
1283         return -1;
1284
1285 #else
1286         DEBUG(0, ("create_pipe_sock: No Unix sockets on this system\n"));
1287         return -1;
1288 #endif /* HAVE_UNIXSOCKET */
1289 }
1290
1291 /****************************************************************************
1292  Get my own canonical name, including domain.
1293 ****************************************************************************/
1294
1295 const char *get_mydnsfullname(void)
1296 {
1297         struct addrinfo *res = NULL;
1298         char my_hostname[HOST_NAME_MAX];
1299         bool ret;
1300         DATA_BLOB tmp;
1301
1302         if (memcache_lookup(NULL, SINGLETON_CACHE,
1303                         data_blob_string_const_null("get_mydnsfullname"),
1304                         &tmp)) {
1305                 SMB_ASSERT(tmp.length > 0);
1306                 return (const char *)tmp.data;
1307         }
1308
1309         /* get my host name */
1310         if (gethostname(my_hostname, sizeof(my_hostname)) == -1) {
1311                 DEBUG(0,("get_mydnsfullname: gethostname failed\n"));
1312                 return NULL;
1313         }
1314
1315         /* Ensure null termination. */
1316         my_hostname[sizeof(my_hostname)-1] = '\0';
1317
1318         ret = interpret_string_addr_internal(&res,
1319                                 my_hostname,
1320                                 AI_ADDRCONFIG|AI_CANONNAME);
1321
1322         if (!ret || res == NULL) {
1323                 DEBUG(3,("get_mydnsfullname: getaddrinfo failed for "
1324                         "name %s [%s]\n",
1325                         my_hostname,
1326                         gai_strerror(ret) ));
1327                 return NULL;
1328         }
1329
1330         /*
1331          * Make sure that getaddrinfo() returns the "correct" host name.
1332          */
1333
1334         if (res->ai_canonname == NULL) {
1335                 DEBUG(3,("get_mydnsfullname: failed to get "
1336                         "canonical name for %s\n",
1337                         my_hostname));
1338                 freeaddrinfo(res);
1339                 return NULL;
1340         }
1341
1342         /* This copies the data, so we must do a lookup
1343          * afterwards to find the value to return.
1344          */
1345
1346         memcache_add(NULL, SINGLETON_CACHE,
1347                         data_blob_string_const_null("get_mydnsfullname"),
1348                         data_blob_string_const_null(res->ai_canonname));
1349
1350         if (!memcache_lookup(NULL, SINGLETON_CACHE,
1351                         data_blob_string_const_null("get_mydnsfullname"),
1352                         &tmp)) {
1353                 tmp = data_blob_talloc(talloc_tos(), res->ai_canonname,
1354                                 strlen(res->ai_canonname) + 1);
1355         }
1356
1357         freeaddrinfo(res);
1358
1359         return (const char *)tmp.data;
1360 }
1361
1362 /************************************************************
1363  Is this my ip address ?
1364 ************************************************************/
1365
1366 static bool is_my_ipaddr(const char *ipaddr_str)
1367 {
1368         struct sockaddr_storage ss;
1369         struct iface_struct *nics;
1370         int i, n;
1371
1372         if (!interpret_string_addr(&ss, ipaddr_str, AI_NUMERICHOST)) {
1373                 return false;
1374         }
1375
1376         if (is_zero_addr(&ss)) {
1377                 return false;
1378         }
1379
1380         if (ismyaddr((struct sockaddr *)&ss) ||
1381                         is_loopback_addr((struct sockaddr *)&ss)) {
1382                 return true;
1383         }
1384
1385         n = get_interfaces(talloc_tos(), &nics);
1386         for (i=0; i<n; i++) {
1387                 if (sockaddr_equal((struct sockaddr *)&nics[i].ip, (struct sockaddr *)&ss)) {
1388                         TALLOC_FREE(nics);
1389                         return true;
1390                 }
1391         }
1392         TALLOC_FREE(nics);
1393         return false;
1394 }
1395
1396 /************************************************************
1397  Is this my name ?
1398 ************************************************************/
1399
1400 bool is_myname_or_ipaddr(const char *s)
1401 {
1402         TALLOC_CTX *ctx = talloc_tos();
1403         char *name = NULL;
1404         const char *dnsname;
1405         char *servername = NULL;
1406
1407         if (!s) {
1408                 return false;
1409         }
1410
1411         /* Santize the string from '\\name' */
1412         name = talloc_strdup(ctx, s);
1413         if (!name) {
1414                 return false;
1415         }
1416
1417         servername = strrchr_m(name, '\\' );
1418         if (!servername) {
1419                 servername = name;
1420         } else {
1421                 servername++;
1422         }
1423
1424         /* Optimize for the common case */
1425         if (strequal(servername, lp_netbios_name())) {
1426                 return true;
1427         }
1428
1429         /* Check for an alias */
1430         if (is_myname(servername)) {
1431                 return true;
1432         }
1433
1434         /* Check for loopback */
1435         if (strequal(servername, "127.0.0.1") ||
1436                         strequal(servername, "::1")) {
1437                 return true;
1438         }
1439
1440         if (strequal(servername, "localhost")) {
1441                 return true;
1442         }
1443
1444         /* Maybe it's my dns name */
1445         dnsname = get_mydnsfullname();
1446         if (dnsname && strequal(servername, dnsname)) {
1447                 return true;
1448         }
1449
1450         /* Maybe its an IP address? */
1451         if (is_ipaddress(servername)) {
1452                 return is_my_ipaddr(servername);
1453         }
1454
1455         /* Handle possible CNAME records - convert to an IP addr. list. */
1456         {
1457                 /* Use DNS to resolve the name, check all addresses. */
1458                 struct addrinfo *p = NULL;
1459                 struct addrinfo *res = NULL;
1460
1461                 if (!interpret_string_addr_internal(&res,
1462                                 servername,
1463                                 AI_ADDRCONFIG)) {
1464                         return false;
1465                 }
1466
1467                 for (p = res; p; p = p->ai_next) {
1468                         char addr[INET6_ADDRSTRLEN];
1469                         struct sockaddr_storage ss;
1470
1471                         ZERO_STRUCT(ss);
1472                         memcpy(&ss, p->ai_addr, p->ai_addrlen);
1473                         print_sockaddr(addr,
1474                                         sizeof(addr),
1475                                         &ss);
1476                         if (is_my_ipaddr(addr)) {
1477                                 freeaddrinfo(res);
1478                                 return true;
1479                         }
1480                 }
1481                 freeaddrinfo(res);
1482         }
1483
1484         /* No match */
1485         return false;
1486 }
1487
1488 struct getaddrinfo_state {
1489         const char *node;
1490         const char *service;
1491         const struct addrinfo *hints;
1492         struct addrinfo *res;
1493         int ret;
1494 };
1495
1496 static void getaddrinfo_do(void *private_data);
1497 static void getaddrinfo_done(struct tevent_req *subreq);
1498
1499 struct tevent_req *getaddrinfo_send(TALLOC_CTX *mem_ctx,
1500                                     struct tevent_context *ev,
1501                                     struct fncall_context *ctx,
1502                                     const char *node,
1503                                     const char *service,
1504                                     const struct addrinfo *hints)
1505 {
1506         struct tevent_req *req, *subreq;
1507         struct getaddrinfo_state *state;
1508
1509         req = tevent_req_create(mem_ctx, &state, struct getaddrinfo_state);
1510         if (req == NULL) {
1511                 return NULL;
1512         }
1513
1514         state->node = node;
1515         state->service = service;
1516         state->hints = hints;
1517
1518         subreq = fncall_send(state, ev, ctx, getaddrinfo_do, state);
1519         if (tevent_req_nomem(subreq, req)) {
1520                 return tevent_req_post(req, ev);
1521         }
1522         tevent_req_set_callback(subreq, getaddrinfo_done, req);
1523         return req;
1524 }
1525
1526 static void getaddrinfo_do(void *private_data)
1527 {
1528         struct getaddrinfo_state *state =
1529                 (struct getaddrinfo_state *)private_data;
1530
1531         state->ret = getaddrinfo(state->node, state->service, state->hints,
1532                                  &state->res);
1533 }
1534
1535 static void getaddrinfo_done(struct tevent_req *subreq)
1536 {
1537         struct tevent_req *req = tevent_req_callback_data(
1538                 subreq, struct tevent_req);
1539         int ret, err;
1540
1541         ret = fncall_recv(subreq, &err);
1542         TALLOC_FREE(subreq);
1543         if (ret == -1) {
1544                 tevent_req_error(req, err);
1545                 return;
1546         }
1547         tevent_req_done(req);
1548 }
1549
1550 int getaddrinfo_recv(struct tevent_req *req, struct addrinfo **res)
1551 {
1552         struct getaddrinfo_state *state = tevent_req_data(
1553                 req, struct getaddrinfo_state);
1554         int err;
1555
1556         if (tevent_req_is_unix_error(req, &err)) {
1557                 switch(err) {
1558                 case ENOMEM:
1559                         return EAI_MEMORY;
1560                 default:
1561                         return EAI_FAIL;
1562                 }
1563         }
1564         if (state->ret == 0) {
1565                 *res = state->res;
1566         }
1567         return state->ret;
1568 }
1569
1570 int poll_one_fd(int fd, int events, int timeout, int *revents)
1571 {
1572         struct pollfd *fds;
1573         int ret;
1574         int saved_errno;
1575
1576         fds = talloc_zero_array(talloc_tos(), struct pollfd, 1);
1577         if (fds == NULL) {
1578                 errno = ENOMEM;
1579                 return -1;
1580         }
1581         fds[0].fd = fd;
1582         fds[0].events = events;
1583
1584         ret = poll(fds, 1, timeout);
1585
1586         /*
1587          * Assign whatever poll did, even in the ret<=0 case.
1588          */
1589         *revents = fds[0].revents;
1590         saved_errno = errno;
1591         TALLOC_FREE(fds);
1592         errno = saved_errno;
1593
1594         return ret;
1595 }
1596
1597 int poll_intr_one_fd(int fd, int events, int timeout, int *revents)
1598 {
1599         struct pollfd pfd;
1600         int ret;
1601
1602         pfd.fd = fd;
1603         pfd.events = events;
1604
1605         ret = sys_poll_intr(&pfd, 1, timeout);
1606         if (ret <= 0) {
1607                 *revents = 0;
1608                 return ret;
1609         }
1610         *revents = pfd.revents;
1611         return 1;
1612 }