a07b71e5ac3df0fe55d292117dc23b13400b2e64
[metze/samba/wip.git] / source3 / smbd / process.c
1 /* 
2    Unix SMB/CIFS implementation.
3    process incoming packets - main loop
4    Copyright (C) Andrew Tridgell 1992-1998
5    Copyright (C) Volker Lendecke 2005-2007
6    
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11    
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16    
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include "includes.h"
22 #include "smbd/globals.h"
23
24 extern bool global_machine_password_needs_changing;
25
26 static void construct_reply_common(struct smb_request *req, const char *inbuf,
27                                    char *outbuf);
28
29 /* Accessor function for smb_read_error for smbd functions. */
30
31 /****************************************************************************
32  Send an smb to a fd.
33 ****************************************************************************/
34
35 bool srv_send_smb(int fd, char *buffer, bool do_encrypt)
36 {
37         size_t len;
38         size_t nwritten=0;
39         ssize_t ret;
40         char *buf_out = buffer;
41
42         /* Sign the outgoing packet if required. */
43         srv_calculate_sign_mac(buf_out);
44
45         if (do_encrypt) {
46                 NTSTATUS status = srv_encrypt_buffer(buffer, &buf_out);
47                 if (!NT_STATUS_IS_OK(status)) {
48                         DEBUG(0, ("send_smb: SMB encryption failed "
49                                 "on outgoing packet! Error %s\n",
50                                 nt_errstr(status) ));
51                         return false;
52                 }
53         }
54
55         len = smb_len(buf_out) + 4;
56
57         while (nwritten < len) {
58                 ret = write_data(fd,buf_out+nwritten,len - nwritten);
59                 if (ret <= 0) {
60                         DEBUG(0,("Error writing %d bytes to client. %d. (%s)\n",
61                                 (int)len,(int)ret, strerror(errno) ));
62                         srv_free_enc_buffer(buf_out);
63                         return false;
64                 }
65                 nwritten += ret;
66         }
67
68         srv_free_enc_buffer(buf_out);
69         return true;
70 }
71
72 /*******************************************************************
73  Setup the word count and byte count for a smb message.
74 ********************************************************************/
75
76 int srv_set_message(char *buf,
77                         int num_words,
78                         int num_bytes,
79                         bool zero)
80 {
81         if (zero && (num_words || num_bytes)) {
82                 memset(buf + smb_size,'\0',num_words*2 + num_bytes);
83         }
84         SCVAL(buf,smb_wct,num_words);
85         SSVAL(buf,smb_vwv + num_words*SIZEOFWORD,num_bytes);
86         smb_setlen(buf,(smb_size + num_words*2 + num_bytes - 4));
87         return (smb_size + num_words*2 + num_bytes);
88 }
89
90 static bool valid_smb_header(const uint8_t *inbuf)
91 {
92         if (is_encrypted_packet(inbuf)) {
93                 return true;
94         }
95         /*
96          * This used to be (strncmp(smb_base(inbuf),"\377SMB",4) == 0)
97          * but it just looks weird to call strncmp for this one.
98          */
99         return (IVAL(smb_base(inbuf), 0) == 0x424D53FF);
100 }
101
102 /* Socket functions for smbd packet processing. */
103
104 static bool valid_packet_size(size_t len)
105 {
106         /*
107          * A WRITEX with CAP_LARGE_WRITEX can be 64k worth of data plus 65 bytes
108          * of header. Don't print the error if this fits.... JRA.
109          */
110
111         if (len > (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE)) {
112                 DEBUG(0,("Invalid packet length! (%lu bytes).\n",
113                                         (unsigned long)len));
114                 return false;
115         }
116         return true;
117 }
118
119 static NTSTATUS read_packet_remainder(int fd, char *buffer,
120                                       unsigned int timeout, ssize_t len)
121 {
122         if (len <= 0) {
123                 return NT_STATUS_OK;
124         }
125
126         return read_socket_with_timeout(fd, buffer, len, len, timeout, NULL);
127 }
128
129 /****************************************************************************
130  Attempt a zerocopy writeX read. We know here that len > smb_size-4
131 ****************************************************************************/
132
133 /*
134  * Unfortunately, earlier versions of smbclient/libsmbclient
135  * don't send this "standard" writeX header. I've fixed this
136  * for 3.2 but we'll use the old method with earlier versions.
137  * Windows and CIFSFS at least use this standard size. Not
138  * sure about MacOSX.
139  */
140
141 #define STANDARD_WRITE_AND_X_HEADER_SIZE (smb_size - 4 + /* basic header */ \
142                                 (2*14) + /* word count (including bcc) */ \
143                                 1 /* pad byte */)
144
145 static NTSTATUS receive_smb_raw_talloc_partial_read(TALLOC_CTX *mem_ctx,
146                                                     const char lenbuf[4],
147                                                     int fd, char **buffer,
148                                                     unsigned int timeout,
149                                                     size_t *p_unread,
150                                                     size_t *len_ret)
151 {
152         /* Size of a WRITEX call (+4 byte len). */
153         char writeX_header[4 + STANDARD_WRITE_AND_X_HEADER_SIZE];
154         ssize_t len = smb_len_large(lenbuf); /* Could be a UNIX large writeX. */
155         ssize_t toread;
156         NTSTATUS status;
157
158         memcpy(writeX_header, lenbuf, 4);
159
160         status = read_socket_with_timeout(
161                 fd, writeX_header + 4,
162                 STANDARD_WRITE_AND_X_HEADER_SIZE,
163                 STANDARD_WRITE_AND_X_HEADER_SIZE,
164                 timeout, NULL);
165
166         if (!NT_STATUS_IS_OK(status)) {
167                 return status;
168         }
169
170         /*
171          * Ok - now try and see if this is a possible
172          * valid writeX call.
173          */
174
175         if (is_valid_writeX_buffer((uint8_t *)writeX_header)) {
176                 /*
177                  * If the data offset is beyond what
178                  * we've read, drain the extra bytes.
179                  */
180                 uint16_t doff = SVAL(writeX_header,smb_vwv11);
181                 ssize_t newlen;
182
183                 if (doff > STANDARD_WRITE_AND_X_HEADER_SIZE) {
184                         size_t drain = doff - STANDARD_WRITE_AND_X_HEADER_SIZE;
185                         if (drain_socket(smbd_server_fd(), drain) != drain) {
186                                 smb_panic("receive_smb_raw_talloc_partial_read:"
187                                         " failed to drain pending bytes");
188                         }
189                 } else {
190                         doff = STANDARD_WRITE_AND_X_HEADER_SIZE;
191                 }
192
193                 /* Spoof down the length and null out the bcc. */
194                 set_message_bcc(writeX_header, 0);
195                 newlen = smb_len(writeX_header);
196
197                 /* Copy the header we've written. */
198
199                 *buffer = (char *)TALLOC_MEMDUP(mem_ctx,
200                                 writeX_header,
201                                 sizeof(writeX_header));
202
203                 if (*buffer == NULL) {
204                         DEBUG(0, ("Could not allocate inbuf of length %d\n",
205                                   (int)sizeof(writeX_header)));
206                         return NT_STATUS_NO_MEMORY;
207                 }
208
209                 /* Work out the remaining bytes. */
210                 *p_unread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
211                 *len_ret = newlen + 4;
212                 return NT_STATUS_OK;
213         }
214
215         if (!valid_packet_size(len)) {
216                 return NT_STATUS_INVALID_PARAMETER;
217         }
218
219         /*
220          * Not a valid writeX call. Just do the standard
221          * talloc and return.
222          */
223
224         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
225
226         if (*buffer == NULL) {
227                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
228                           (int)len+4));
229                 return NT_STATUS_NO_MEMORY;
230         }
231
232         /* Copy in what we already read. */
233         memcpy(*buffer,
234                 writeX_header,
235                 4 + STANDARD_WRITE_AND_X_HEADER_SIZE);
236         toread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
237
238         if(toread > 0) {
239                 status = read_packet_remainder(
240                         fd, (*buffer) + 4 + STANDARD_WRITE_AND_X_HEADER_SIZE,
241                         timeout, toread);
242
243                 if (!NT_STATUS_IS_OK(status)) {
244                         DEBUG(10, ("receive_smb_raw_talloc_partial_read: %s\n",
245                                    nt_errstr(status)));
246                         return status;
247                 }
248         }
249
250         *len_ret = len + 4;
251         return NT_STATUS_OK;
252 }
253
254 static NTSTATUS receive_smb_raw_talloc(TALLOC_CTX *mem_ctx, int fd,
255                                        char **buffer, unsigned int timeout,
256                                        size_t *p_unread, size_t *plen)
257 {
258         char lenbuf[4];
259         size_t len;
260         int min_recv_size = lp_min_receive_file_size();
261         NTSTATUS status;
262
263         *p_unread = 0;
264
265         status = read_smb_length_return_keepalive(fd, lenbuf, timeout, &len);
266         if (!NT_STATUS_IS_OK(status)) {
267                 DEBUG(10, ("receive_smb_raw: %s\n", nt_errstr(status)));
268                 return status;
269         }
270
271         if (CVAL(lenbuf,0) == 0 &&
272                         min_recv_size &&
273                         smb_len_large(lenbuf) > (min_recv_size + STANDARD_WRITE_AND_X_HEADER_SIZE) && /* Could be a UNIX large writeX. */
274                         !srv_is_signing_active()) {
275
276                 return receive_smb_raw_talloc_partial_read(
277                         mem_ctx, lenbuf, fd, buffer, timeout, p_unread, plen);
278         }
279
280         if (!valid_packet_size(len)) {
281                 return NT_STATUS_INVALID_PARAMETER;
282         }
283
284         /*
285          * The +4 here can't wrap, we've checked the length above already.
286          */
287
288         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
289
290         if (*buffer == NULL) {
291                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
292                           (int)len+4));
293                 return NT_STATUS_NO_MEMORY;
294         }
295
296         memcpy(*buffer, lenbuf, sizeof(lenbuf));
297
298         status = read_packet_remainder(fd, (*buffer)+4, timeout, len);
299         if (!NT_STATUS_IS_OK(status)) {
300                 return status;
301         }
302
303         *plen = len + 4;
304         return NT_STATUS_OK;
305 }
306
307 static NTSTATUS receive_smb_talloc(TALLOC_CTX *mem_ctx, int fd,
308                                    char **buffer, unsigned int timeout,
309                                    size_t *p_unread, bool *p_encrypted,
310                                    size_t *p_len)
311 {
312         size_t len = 0;
313         NTSTATUS status;
314
315         *p_encrypted = false;
316
317         status = receive_smb_raw_talloc(mem_ctx, fd, buffer, timeout,
318                                         p_unread, &len);
319         if (!NT_STATUS_IS_OK(status)) {
320                 return status;
321         }
322
323         if (is_encrypted_packet((uint8_t *)*buffer)) {
324                 status = srv_decrypt_buffer(*buffer);
325                 if (!NT_STATUS_IS_OK(status)) {
326                         DEBUG(0, ("receive_smb_talloc: SMB decryption failed on "
327                                 "incoming packet! Error %s\n",
328                                 nt_errstr(status) ));
329                         return status;
330                 }
331                 *p_encrypted = true;
332         }
333
334         /* Check the incoming SMB signature. */
335         if (!srv_check_sign_mac(*buffer, true)) {
336                 DEBUG(0, ("receive_smb: SMB Signature verification failed on "
337                           "incoming packet!\n"));
338                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
339         }
340
341         *p_len = len;
342         return NT_STATUS_OK;
343 }
344
345 /*
346  * Initialize a struct smb_request from an inbuf
347  */
348
349 void init_smb_request(struct smb_request *req,
350                         const uint8 *inbuf,
351                         size_t unread_bytes,
352                         bool encrypted)
353 {
354         size_t req_size = smb_len(inbuf) + 4;
355         /* Ensure we have at least smb_size bytes. */
356         if (req_size < smb_size) {
357                 DEBUG(0,("init_smb_request: invalid request size %u\n",
358                         (unsigned int)req_size ));
359                 exit_server_cleanly("Invalid SMB request");
360         }
361         req->cmd    = CVAL(inbuf, smb_com);
362         req->flags2 = SVAL(inbuf, smb_flg2);
363         req->smbpid = SVAL(inbuf, smb_pid);
364         req->mid    = SVAL(inbuf, smb_mid);
365         req->vuid   = SVAL(inbuf, smb_uid);
366         req->tid    = SVAL(inbuf, smb_tid);
367         req->wct    = CVAL(inbuf, smb_wct);
368         req->vwv    = (uint16_t *)(inbuf+smb_vwv);
369         req->buflen = smb_buflen(inbuf);
370         req->buf    = (const uint8_t *)smb_buf(inbuf);
371         req->unread_bytes = unread_bytes;
372         req->encrypted = encrypted;
373         req->conn = conn_find(req->tid);
374         req->chain_fsp = NULL;
375         req->chain_outbuf = NULL;
376
377         /* Ensure we have at least wct words and 2 bytes of bcc. */
378         if (smb_size + req->wct*2 > req_size) {
379                 DEBUG(0,("init_smb_request: invalid wct number %u (size %u)\n",
380                         (unsigned int)req->wct,
381                         (unsigned int)req_size));
382                 exit_server_cleanly("Invalid SMB request");
383         }
384         /* Ensure bcc is correct. */
385         if (((uint8 *)smb_buf(inbuf)) + req->buflen > inbuf + req_size) {
386                 DEBUG(0,("init_smb_request: invalid bcc number %u "
387                         "(wct = %u, size %u)\n",
388                         (unsigned int)req->buflen,
389                         (unsigned int)req->wct,
390                         (unsigned int)req_size));
391                 exit_server_cleanly("Invalid SMB request");
392         }
393         req->outbuf = NULL;
394 }
395
396 static void process_smb(struct smbd_server_connection *conn,
397                         uint8_t *inbuf, size_t nread, size_t unread_bytes,
398                         bool encrypted);
399
400 static void smbd_deferred_open_timer(struct event_context *ev,
401                                      struct timed_event *te,
402                                      struct timeval _tval,
403                                      void *private_data)
404 {
405         struct pending_message_list *msg = talloc_get_type(private_data,
406                                            struct pending_message_list);
407         TALLOC_CTX *mem_ctx = talloc_tos();
408         uint8_t *inbuf;
409
410         inbuf = (uint8_t *)talloc_memdup(mem_ctx, msg->buf.data,
411                                          msg->buf.length);
412         if (inbuf == NULL) {
413                 exit_server("smbd_deferred_open_timer: talloc failed\n");
414                 return;
415         }
416
417         /* We leave this message on the queue so the open code can
418            know this is a retry. */
419         DEBUG(5,("smbd_deferred_open_timer: trigger mid %u.\n",
420                 (unsigned int)SVAL(msg->buf.data,smb_mid)));
421
422         process_smb(smbd_server_conn, inbuf,
423                     msg->buf.length, 0,
424                     msg->encrypted);
425 }
426
427 /****************************************************************************
428  Function to push a message onto the tail of a linked list of smb messages ready
429  for processing.
430 ****************************************************************************/
431
432 static bool push_queued_message(struct smb_request *req,
433                                 struct timeval request_time,
434                                 struct timeval end_time,
435                                 char *private_data, size_t private_len)
436 {
437         int msg_len = smb_len(req->inbuf) + 4;
438         struct pending_message_list *msg;
439
440         msg = TALLOC_ZERO_P(NULL, struct pending_message_list);
441
442         if(msg == NULL) {
443                 DEBUG(0,("push_message: malloc fail (1)\n"));
444                 return False;
445         }
446
447         msg->buf = data_blob_talloc(msg, req->inbuf, msg_len);
448         if(msg->buf.data == NULL) {
449                 DEBUG(0,("push_message: malloc fail (2)\n"));
450                 TALLOC_FREE(msg);
451                 return False;
452         }
453
454         msg->request_time = request_time;
455         msg->encrypted = req->encrypted;
456
457         if (private_data) {
458                 msg->private_data = data_blob_talloc(msg, private_data,
459                                                      private_len);
460                 if (msg->private_data.data == NULL) {
461                         DEBUG(0,("push_message: malloc fail (3)\n"));
462                         TALLOC_FREE(msg);
463                         return False;
464                 }
465         }
466
467         msg->te = event_add_timed(smbd_event_context(),
468                                   msg,
469                                   end_time,
470                                   smbd_deferred_open_timer,
471                                   msg);
472         if (!msg->te) {
473                 DEBUG(0,("push_message: event_add_timed failed\n"));
474                 TALLOC_FREE(msg);
475                 return false;
476         }
477
478         DLIST_ADD_END(deferred_open_queue, msg, struct pending_message_list *);
479
480         DEBUG(10,("push_message: pushed message length %u on "
481                   "deferred_open_queue\n", (unsigned int)msg_len));
482
483         return True;
484 }
485
486 /****************************************************************************
487  Function to delete a sharing violation open message by mid.
488 ****************************************************************************/
489
490 void remove_deferred_open_smb_message(uint16 mid)
491 {
492         struct pending_message_list *pml;
493
494         for (pml = deferred_open_queue; pml; pml = pml->next) {
495                 if (mid == SVAL(pml->buf.data,smb_mid)) {
496                         DEBUG(10,("remove_sharing_violation_open_smb_message: "
497                                   "deleting mid %u len %u\n",
498                                   (unsigned int)mid,
499                                   (unsigned int)pml->buf.length ));
500                         DLIST_REMOVE(deferred_open_queue, pml);
501                         TALLOC_FREE(pml);
502                         return;
503                 }
504         }
505 }
506
507 /****************************************************************************
508  Move a sharing violation open retry message to the front of the list and
509  schedule it for immediate processing.
510 ****************************************************************************/
511
512 void schedule_deferred_open_smb_message(uint16 mid)
513 {
514         struct pending_message_list *pml;
515         int i = 0;
516
517         for (pml = deferred_open_queue; pml; pml = pml->next) {
518                 uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
519
520                 DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
521                         (unsigned int)msg_mid ));
522
523                 if (mid == msg_mid) {
524                         struct timed_event *te;
525
526                         DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
527                                 mid ));
528
529                         te = event_add_timed(smbd_event_context(),
530                                              pml,
531                                              timeval_zero(),
532                                              smbd_deferred_open_timer,
533                                              pml);
534                         if (!te) {
535                                 DEBUG(10,("schedule_deferred_open_smb_message: "
536                                           "event_add_timed() failed, skipping mid %u\n",
537                                           mid ));
538                         }
539
540                         TALLOC_FREE(pml->te);
541                         pml->te = te;
542                         DLIST_PROMOTE(deferred_open_queue, pml);
543                         return;
544                 }
545         }
546
547         DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
548                 mid ));
549 }
550
551 /****************************************************************************
552  Return true if this mid is on the deferred queue.
553 ****************************************************************************/
554
555 bool open_was_deferred(uint16 mid)
556 {
557         struct pending_message_list *pml;
558
559         for (pml = deferred_open_queue; pml; pml = pml->next) {
560                 if (SVAL(pml->buf.data,smb_mid) == mid) {
561                         return True;
562                 }
563         }
564         return False;
565 }
566
567 /****************************************************************************
568  Return the message queued by this mid.
569 ****************************************************************************/
570
571 struct pending_message_list *get_open_deferred_message(uint16 mid)
572 {
573         struct pending_message_list *pml;
574
575         for (pml = deferred_open_queue; pml; pml = pml->next) {
576                 if (SVAL(pml->buf.data,smb_mid) == mid) {
577                         return pml;
578                 }
579         }
580         return NULL;
581 }
582
583 /****************************************************************************
584  Function to push a deferred open smb message onto a linked list of local smb
585  messages ready for processing.
586 ****************************************************************************/
587
588 bool push_deferred_smb_message(struct smb_request *req,
589                                struct timeval request_time,
590                                struct timeval timeout,
591                                char *private_data, size_t priv_len)
592 {
593         struct timeval end_time;
594
595         if (req->unread_bytes) {
596                 DEBUG(0,("push_deferred_smb_message: logic error ! "
597                         "unread_bytes = %u\n",
598                         (unsigned int)req->unread_bytes ));
599                 smb_panic("push_deferred_smb_message: "
600                         "logic error unread_bytes != 0" );
601         }
602
603         end_time = timeval_sum(&request_time, &timeout);
604
605         DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
606                   "timeout time [%u.%06u]\n",
607                   (unsigned int) smb_len(req->inbuf)+4, (unsigned int)req->mid,
608                   (unsigned int)end_time.tv_sec,
609                   (unsigned int)end_time.tv_usec));
610
611         return push_queued_message(req, request_time, end_time,
612                                    private_data, priv_len);
613 }
614
615 struct idle_event {
616         struct timed_event *te;
617         struct timeval interval;
618         char *name;
619         bool (*handler)(const struct timeval *now, void *private_data);
620         void *private_data;
621 };
622
623 static void smbd_idle_event_handler(struct event_context *ctx,
624                                     struct timed_event *te,
625                                     struct timeval now,
626                                     void *private_data)
627 {
628         struct idle_event *event =
629                 talloc_get_type_abort(private_data, struct idle_event);
630
631         TALLOC_FREE(event->te);
632
633         DEBUG(10,("smbd_idle_event_handler: %s %p called\n",
634                   event->name, event->te));
635
636         if (!event->handler(&now, event->private_data)) {
637                 DEBUG(10,("smbd_idle_event_handler: %s %p stopped\n",
638                           event->name, event->te));
639                 /* Don't repeat, delete ourselves */
640                 TALLOC_FREE(event);
641                 return;
642         }
643
644         DEBUG(10,("smbd_idle_event_handler: %s %p rescheduled\n",
645                   event->name, event->te));
646
647         event->te = event_add_timed(ctx, event,
648                                     timeval_sum(&now, &event->interval),
649                                     smbd_idle_event_handler, event);
650
651         /* We can't do much but fail here. */
652         SMB_ASSERT(event->te != NULL);
653 }
654
655 struct idle_event *event_add_idle(struct event_context *event_ctx,
656                                   TALLOC_CTX *mem_ctx,
657                                   struct timeval interval,
658                                   const char *name,
659                                   bool (*handler)(const struct timeval *now,
660                                                   void *private_data),
661                                   void *private_data)
662 {
663         struct idle_event *result;
664         struct timeval now = timeval_current();
665
666         result = TALLOC_P(mem_ctx, struct idle_event);
667         if (result == NULL) {
668                 DEBUG(0, ("talloc failed\n"));
669                 return NULL;
670         }
671
672         result->interval = interval;
673         result->handler = handler;
674         result->private_data = private_data;
675
676         if (!(result->name = talloc_asprintf(result, "idle_evt(%s)", name))) {
677                 DEBUG(0, ("talloc failed\n"));
678                 TALLOC_FREE(result);
679                 return NULL;
680         }
681
682         result->te = event_add_timed(event_ctx, result,
683                                      timeval_sum(&now, &interval),
684                                      smbd_idle_event_handler, result);
685         if (result->te == NULL) {
686                 DEBUG(0, ("event_add_timed failed\n"));
687                 TALLOC_FREE(result);
688                 return NULL;
689         }
690
691         DEBUG(10,("event_add_idle: %s %p\n", result->name, result->te));
692         return result;
693 }
694
695 /****************************************************************************
696  Do all async processing in here. This includes kernel oplock messages, change
697  notify events etc.
698 ****************************************************************************/
699
700 static void async_processing(void)
701 {
702         DEBUG(10,("async_processing: Doing async processing.\n"));
703
704         process_aio_queue();
705
706         process_kernel_oplocks(smbd_messaging_context());
707
708         /* Do the aio check again after receive_local_message as it does a
709            select and may have eaten our signal. */
710         /* Is this till true? -- vl */
711         process_aio_queue();
712
713         if (got_sig_term) {
714                 exit_server_cleanly("termination signal");
715         }
716
717         /* check for sighup processing */
718         if (reload_after_sighup) {
719                 change_to_root_user();
720                 DEBUG(1,("Reloading services after SIGHUP\n"));
721                 reload_services(False);
722                 reload_after_sighup = 0;
723         }
724 }
725
726 /****************************************************************************
727   Do a select on an two fd's - with timeout. 
728
729   If a local udp message has been pushed onto the
730   queue (this can only happen during oplock break
731   processing) call async_processing()
732
733   If a pending smb message has been pushed onto the
734   queue (this can only happen during oplock break
735   processing) return this next.
736
737   If the first smbfd is ready then read an smb from it.
738   if the second (loopback UDP) fd is ready then read a message
739   from it and setup the buffer header to identify the length
740   and from address.
741   Returns False on timeout or error.
742   Else returns True.
743
744 The timeout is in milliseconds
745 ****************************************************************************/
746
747 static NTSTATUS smbd_server_connection_loop_once(struct smbd_server_connection *conn)
748 {
749         fd_set r_fds, w_fds;
750         int selrtn;
751         struct timeval to;
752         int maxfd = 0;
753
754         to.tv_sec = SMBD_SELECT_TIMEOUT;
755         to.tv_usec = 0;
756
757         /*
758          * Setup the select fd sets.
759          */
760
761         FD_ZERO(&r_fds);
762         FD_ZERO(&w_fds);
763
764         /*
765          * Ensure we process oplock break messages by preference.
766          * We have to do this before the select, after the select
767          * and if the select returns EINTR. This is due to the fact
768          * that the selects called from async_processing can eat an EINTR
769          * caused by a signal (we can't take the break message there).
770          * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
771          */
772
773         if (oplock_message_waiting()) {
774                 DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
775                 async_processing();
776                 /*
777                  * After async processing we must go and do the select again, as
778                  * the state of the flag in fds for the server file descriptor is
779                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
780                  */
781                 return NT_STATUS_RETRY;
782         }
783
784         /*
785          * Are there any timed events waiting ? If so, ensure we don't
786          * select for longer than it would take to wait for them.
787          */
788
789         {
790                 struct timeval now;
791                 GetTimeOfDay(&now);
792
793                 event_add_to_select_args(smbd_event_context(), &now,
794                                          &r_fds, &w_fds, &to, &maxfd);
795         }
796
797         /* Process a signal and timed events now... */
798         if (run_events(smbd_event_context(), 0, NULL, NULL)) {
799                 return NT_STATUS_RETRY;
800         }
801
802         {
803                 int sav;
804                 START_PROFILE(smbd_idle);
805
806                 selrtn = sys_select(maxfd+1,&r_fds,&w_fds,NULL,&to);
807                 sav = errno;
808
809                 END_PROFILE(smbd_idle);
810                 errno = sav;
811         }
812
813         if (run_events(smbd_event_context(), selrtn, &r_fds, &w_fds)) {
814                 return NT_STATUS_RETRY;
815         }
816
817         /* if we get EINTR then maybe we have received an oplock
818            signal - treat this as select returning 1. This is ugly, but
819            is the best we can do until the oplock code knows more about
820            signals */
821         if (selrtn == -1 && errno == EINTR) {
822                 async_processing();
823                 /*
824                  * After async processing we must go and do the select again, as
825                  * the state of the flag in fds for the server file descriptor is
826                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
827                  */
828                 return NT_STATUS_RETRY;
829         }
830
831         /* Check if error */
832         if (selrtn == -1) {
833                 /* something is wrong. Maybe the socket is dead? */
834                 return map_nt_error_from_unix(errno);
835         }
836
837         /* Did we timeout ? */
838         if (selrtn == 0) {
839                 return NT_STATUS_RETRY;
840         }
841
842         /* should not be reached */
843         return NT_STATUS_INTERNAL_ERROR;
844 }
845
846 /*
847  * Only allow 5 outstanding trans requests. We're allocating memory, so
848  * prevent a DoS.
849  */
850
851 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
852 {
853         int count = 0;
854         for (; list != NULL; list = list->next) {
855
856                 if (list->mid == mid) {
857                         return NT_STATUS_INVALID_PARAMETER;
858                 }
859
860                 count += 1;
861         }
862         if (count > 5) {
863                 return NT_STATUS_INSUFFICIENT_RESOURCES;
864         }
865
866         return NT_STATUS_OK;
867 }
868
869 /****************************************************************************
870  We're terminating and have closed all our files/connections etc.
871  If there are any pending local messages we need to respond to them
872  before termination so that other smbds don't think we just died whilst
873  holding oplocks.
874 ****************************************************************************/
875
876 void respond_to_all_remaining_local_messages(void)
877 {
878         /*
879          * Assert we have no exclusive open oplocks.
880          */
881
882         if(get_number_of_exclusive_open_oplocks()) {
883                 DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
884                         get_number_of_exclusive_open_oplocks() ));
885                 return;
886         }
887
888         process_kernel_oplocks(smbd_messaging_context());
889
890         return;
891 }
892
893
894 /*
895 These flags determine some of the permissions required to do an operation 
896
897 Note that I don't set NEED_WRITE on some write operations because they
898 are used by some brain-dead clients when printing, and I don't want to
899 force write permissions on print services.
900 */
901 #define AS_USER (1<<0)
902 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
903 #define TIME_INIT (1<<2)
904 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
905 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
906 #define DO_CHDIR (1<<6)
907
908 /* 
909    define a list of possible SMB messages and their corresponding
910    functions. Any message that has a NULL function is unimplemented -
911    please feel free to contribute implementations!
912 */
913 static const struct smb_message_struct {
914         const char *name;
915         void (*fn)(struct smb_request *req);
916         int flags;
917 } smb_messages[256] = {
918
919 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
920 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
921 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
922 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
923 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
924 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
925 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE },
926 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
927 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
928 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
929 /* 0x0a */ { "SMBread",reply_read,AS_USER},
930 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
931 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
932 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
933 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
934 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER},
935 /* 0x10 */ { "SMBcheckpath",reply_checkpath,AS_USER},
936 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
937 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
938 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
939 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
940 /* 0x15 */ { NULL, NULL, 0 },
941 /* 0x16 */ { NULL, NULL, 0 },
942 /* 0x17 */ { NULL, NULL, 0 },
943 /* 0x18 */ { NULL, NULL, 0 },
944 /* 0x19 */ { NULL, NULL, 0 },
945 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
946 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
947 /* 0x1c */ { "SMBreadBs",reply_readbs,AS_USER },
948 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
949 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
950 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
951 /* 0x20 */ { "SMBwritec", NULL,0},
952 /* 0x21 */ { NULL, NULL, 0 },
953 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
954 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
955 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
956 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
957 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
958 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
959 /* 0x28 */ { "SMBioctls", NULL,AS_USER},
960 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
961 /* 0x2a */ { "SMBmove", NULL,AS_USER | NEED_WRITE },
962 /* 0x2b */ { "SMBecho",reply_echo,0},
963 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
964 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
965 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
966 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
967 /* 0x30 */ { NULL, NULL, 0 },
968 /* 0x31 */ { NULL, NULL, 0 },
969 /* 0x32 */ { "SMBtrans2",reply_trans2, AS_USER | CAN_IPC },
970 /* 0x33 */ { "SMBtranss2",reply_transs2, AS_USER},
971 /* 0x34 */ { "SMBfindclose",reply_findclose,AS_USER},
972 /* 0x35 */ { "SMBfindnclose",reply_findnclose,AS_USER},
973 /* 0x36 */ { NULL, NULL, 0 },
974 /* 0x37 */ { NULL, NULL, 0 },
975 /* 0x38 */ { NULL, NULL, 0 },
976 /* 0x39 */ { NULL, NULL, 0 },
977 /* 0x3a */ { NULL, NULL, 0 },
978 /* 0x3b */ { NULL, NULL, 0 },
979 /* 0x3c */ { NULL, NULL, 0 },
980 /* 0x3d */ { NULL, NULL, 0 },
981 /* 0x3e */ { NULL, NULL, 0 },
982 /* 0x3f */ { NULL, NULL, 0 },
983 /* 0x40 */ { NULL, NULL, 0 },
984 /* 0x41 */ { NULL, NULL, 0 },
985 /* 0x42 */ { NULL, NULL, 0 },
986 /* 0x43 */ { NULL, NULL, 0 },
987 /* 0x44 */ { NULL, NULL, 0 },
988 /* 0x45 */ { NULL, NULL, 0 },
989 /* 0x46 */ { NULL, NULL, 0 },
990 /* 0x47 */ { NULL, NULL, 0 },
991 /* 0x48 */ { NULL, NULL, 0 },
992 /* 0x49 */ { NULL, NULL, 0 },
993 /* 0x4a */ { NULL, NULL, 0 },
994 /* 0x4b */ { NULL, NULL, 0 },
995 /* 0x4c */ { NULL, NULL, 0 },
996 /* 0x4d */ { NULL, NULL, 0 },
997 /* 0x4e */ { NULL, NULL, 0 },
998 /* 0x4f */ { NULL, NULL, 0 },
999 /* 0x50 */ { NULL, NULL, 0 },
1000 /* 0x51 */ { NULL, NULL, 0 },
1001 /* 0x52 */ { NULL, NULL, 0 },
1002 /* 0x53 */ { NULL, NULL, 0 },
1003 /* 0x54 */ { NULL, NULL, 0 },
1004 /* 0x55 */ { NULL, NULL, 0 },
1005 /* 0x56 */ { NULL, NULL, 0 },
1006 /* 0x57 */ { NULL, NULL, 0 },
1007 /* 0x58 */ { NULL, NULL, 0 },
1008 /* 0x59 */ { NULL, NULL, 0 },
1009 /* 0x5a */ { NULL, NULL, 0 },
1010 /* 0x5b */ { NULL, NULL, 0 },
1011 /* 0x5c */ { NULL, NULL, 0 },
1012 /* 0x5d */ { NULL, NULL, 0 },
1013 /* 0x5e */ { NULL, NULL, 0 },
1014 /* 0x5f */ { NULL, NULL, 0 },
1015 /* 0x60 */ { NULL, NULL, 0 },
1016 /* 0x61 */ { NULL, NULL, 0 },
1017 /* 0x62 */ { NULL, NULL, 0 },
1018 /* 0x63 */ { NULL, NULL, 0 },
1019 /* 0x64 */ { NULL, NULL, 0 },
1020 /* 0x65 */ { NULL, NULL, 0 },
1021 /* 0x66 */ { NULL, NULL, 0 },
1022 /* 0x67 */ { NULL, NULL, 0 },
1023 /* 0x68 */ { NULL, NULL, 0 },
1024 /* 0x69 */ { NULL, NULL, 0 },
1025 /* 0x6a */ { NULL, NULL, 0 },
1026 /* 0x6b */ { NULL, NULL, 0 },
1027 /* 0x6c */ { NULL, NULL, 0 },
1028 /* 0x6d */ { NULL, NULL, 0 },
1029 /* 0x6e */ { NULL, NULL, 0 },
1030 /* 0x6f */ { NULL, NULL, 0 },
1031 /* 0x70 */ { "SMBtcon",reply_tcon,0},
1032 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
1033 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
1034 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
1035 /* 0x74 */ { "SMBulogoffX",reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
1036 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
1037 /* 0x76 */ { NULL, NULL, 0 },
1038 /* 0x77 */ { NULL, NULL, 0 },
1039 /* 0x78 */ { NULL, NULL, 0 },
1040 /* 0x79 */ { NULL, NULL, 0 },
1041 /* 0x7a */ { NULL, NULL, 0 },
1042 /* 0x7b */ { NULL, NULL, 0 },
1043 /* 0x7c */ { NULL, NULL, 0 },
1044 /* 0x7d */ { NULL, NULL, 0 },
1045 /* 0x7e */ { NULL, NULL, 0 },
1046 /* 0x7f */ { NULL, NULL, 0 },
1047 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
1048 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
1049 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
1050 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
1051 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
1052 /* 0x85 */ { NULL, NULL, 0 },
1053 /* 0x86 */ { NULL, NULL, 0 },
1054 /* 0x87 */ { NULL, NULL, 0 },
1055 /* 0x88 */ { NULL, NULL, 0 },
1056 /* 0x89 */ { NULL, NULL, 0 },
1057 /* 0x8a */ { NULL, NULL, 0 },
1058 /* 0x8b */ { NULL, NULL, 0 },
1059 /* 0x8c */ { NULL, NULL, 0 },
1060 /* 0x8d */ { NULL, NULL, 0 },
1061 /* 0x8e */ { NULL, NULL, 0 },
1062 /* 0x8f */ { NULL, NULL, 0 },
1063 /* 0x90 */ { NULL, NULL, 0 },
1064 /* 0x91 */ { NULL, NULL, 0 },
1065 /* 0x92 */ { NULL, NULL, 0 },
1066 /* 0x93 */ { NULL, NULL, 0 },
1067 /* 0x94 */ { NULL, NULL, 0 },
1068 /* 0x95 */ { NULL, NULL, 0 },
1069 /* 0x96 */ { NULL, NULL, 0 },
1070 /* 0x97 */ { NULL, NULL, 0 },
1071 /* 0x98 */ { NULL, NULL, 0 },
1072 /* 0x99 */ { NULL, NULL, 0 },
1073 /* 0x9a */ { NULL, NULL, 0 },
1074 /* 0x9b */ { NULL, NULL, 0 },
1075 /* 0x9c */ { NULL, NULL, 0 },
1076 /* 0x9d */ { NULL, NULL, 0 },
1077 /* 0x9e */ { NULL, NULL, 0 },
1078 /* 0x9f */ { NULL, NULL, 0 },
1079 /* 0xa0 */ { "SMBnttrans",reply_nttrans, AS_USER | CAN_IPC },
1080 /* 0xa1 */ { "SMBnttranss",reply_nttranss, AS_USER | CAN_IPC },
1081 /* 0xa2 */ { "SMBntcreateX",reply_ntcreate_and_X, AS_USER | CAN_IPC },
1082 /* 0xa3 */ { NULL, NULL, 0 },
1083 /* 0xa4 */ { "SMBntcancel",reply_ntcancel, 0 },
1084 /* 0xa5 */ { "SMBntrename",reply_ntrename, AS_USER | NEED_WRITE },
1085 /* 0xa6 */ { NULL, NULL, 0 },
1086 /* 0xa7 */ { NULL, NULL, 0 },
1087 /* 0xa8 */ { NULL, NULL, 0 },
1088 /* 0xa9 */ { NULL, NULL, 0 },
1089 /* 0xaa */ { NULL, NULL, 0 },
1090 /* 0xab */ { NULL, NULL, 0 },
1091 /* 0xac */ { NULL, NULL, 0 },
1092 /* 0xad */ { NULL, NULL, 0 },
1093 /* 0xae */ { NULL, NULL, 0 },
1094 /* 0xaf */ { NULL, NULL, 0 },
1095 /* 0xb0 */ { NULL, NULL, 0 },
1096 /* 0xb1 */ { NULL, NULL, 0 },
1097 /* 0xb2 */ { NULL, NULL, 0 },
1098 /* 0xb3 */ { NULL, NULL, 0 },
1099 /* 0xb4 */ { NULL, NULL, 0 },
1100 /* 0xb5 */ { NULL, NULL, 0 },
1101 /* 0xb6 */ { NULL, NULL, 0 },
1102 /* 0xb7 */ { NULL, NULL, 0 },
1103 /* 0xb8 */ { NULL, NULL, 0 },
1104 /* 0xb9 */ { NULL, NULL, 0 },
1105 /* 0xba */ { NULL, NULL, 0 },
1106 /* 0xbb */ { NULL, NULL, 0 },
1107 /* 0xbc */ { NULL, NULL, 0 },
1108 /* 0xbd */ { NULL, NULL, 0 },
1109 /* 0xbe */ { NULL, NULL, 0 },
1110 /* 0xbf */ { NULL, NULL, 0 },
1111 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
1112 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
1113 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
1114 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
1115 /* 0xc4 */ { NULL, NULL, 0 },
1116 /* 0xc5 */ { NULL, NULL, 0 },
1117 /* 0xc6 */ { NULL, NULL, 0 },
1118 /* 0xc7 */ { NULL, NULL, 0 },
1119 /* 0xc8 */ { NULL, NULL, 0 },
1120 /* 0xc9 */ { NULL, NULL, 0 },
1121 /* 0xca */ { NULL, NULL, 0 },
1122 /* 0xcb */ { NULL, NULL, 0 },
1123 /* 0xcc */ { NULL, NULL, 0 },
1124 /* 0xcd */ { NULL, NULL, 0 },
1125 /* 0xce */ { NULL, NULL, 0 },
1126 /* 0xcf */ { NULL, NULL, 0 },
1127 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
1128 /* 0xd1 */ { "SMBsendb", NULL,AS_GUEST},
1129 /* 0xd2 */ { "SMBfwdname", NULL,AS_GUEST},
1130 /* 0xd3 */ { "SMBcancelf", NULL,AS_GUEST},
1131 /* 0xd4 */ { "SMBgetmac", NULL,AS_GUEST},
1132 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
1133 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
1134 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
1135 /* 0xd8 */ { NULL, NULL, 0 },
1136 /* 0xd9 */ { NULL, NULL, 0 },
1137 /* 0xda */ { NULL, NULL, 0 },
1138 /* 0xdb */ { NULL, NULL, 0 },
1139 /* 0xdc */ { NULL, NULL, 0 },
1140 /* 0xdd */ { NULL, NULL, 0 },
1141 /* 0xde */ { NULL, NULL, 0 },
1142 /* 0xdf */ { NULL, NULL, 0 },
1143 /* 0xe0 */ { NULL, NULL, 0 },
1144 /* 0xe1 */ { NULL, NULL, 0 },
1145 /* 0xe2 */ { NULL, NULL, 0 },
1146 /* 0xe3 */ { NULL, NULL, 0 },
1147 /* 0xe4 */ { NULL, NULL, 0 },
1148 /* 0xe5 */ { NULL, NULL, 0 },
1149 /* 0xe6 */ { NULL, NULL, 0 },
1150 /* 0xe7 */ { NULL, NULL, 0 },
1151 /* 0xe8 */ { NULL, NULL, 0 },
1152 /* 0xe9 */ { NULL, NULL, 0 },
1153 /* 0xea */ { NULL, NULL, 0 },
1154 /* 0xeb */ { NULL, NULL, 0 },
1155 /* 0xec */ { NULL, NULL, 0 },
1156 /* 0xed */ { NULL, NULL, 0 },
1157 /* 0xee */ { NULL, NULL, 0 },
1158 /* 0xef */ { NULL, NULL, 0 },
1159 /* 0xf0 */ { NULL, NULL, 0 },
1160 /* 0xf1 */ { NULL, NULL, 0 },
1161 /* 0xf2 */ { NULL, NULL, 0 },
1162 /* 0xf3 */ { NULL, NULL, 0 },
1163 /* 0xf4 */ { NULL, NULL, 0 },
1164 /* 0xf5 */ { NULL, NULL, 0 },
1165 /* 0xf6 */ { NULL, NULL, 0 },
1166 /* 0xf7 */ { NULL, NULL, 0 },
1167 /* 0xf8 */ { NULL, NULL, 0 },
1168 /* 0xf9 */ { NULL, NULL, 0 },
1169 /* 0xfa */ { NULL, NULL, 0 },
1170 /* 0xfb */ { NULL, NULL, 0 },
1171 /* 0xfc */ { NULL, NULL, 0 },
1172 /* 0xfd */ { NULL, NULL, 0 },
1173 /* 0xfe */ { NULL, NULL, 0 },
1174 /* 0xff */ { NULL, NULL, 0 }
1175
1176 };
1177
1178 /*******************************************************************
1179  allocate and initialize a reply packet
1180 ********************************************************************/
1181
1182 static bool create_outbuf(TALLOC_CTX *mem_ctx, struct smb_request *req,
1183                           const char *inbuf, char **outbuf, uint8_t num_words,
1184                           uint32_t num_bytes)
1185 {
1186         /*
1187          * Protect against integer wrap
1188          */
1189         if ((num_bytes > 0xffffff)
1190             || ((num_bytes + smb_size + num_words*2) > 0xffffff)) {
1191                 char *msg;
1192                 if (asprintf(&msg, "num_bytes too large: %u",
1193                              (unsigned)num_bytes) == -1) {
1194                         msg = CONST_DISCARD(char *, "num_bytes too large");
1195                 }
1196                 smb_panic(msg);
1197         }
1198
1199         *outbuf = TALLOC_ARRAY(mem_ctx, char,
1200                                smb_size + num_words*2 + num_bytes);
1201         if (*outbuf == NULL) {
1202                 return false;
1203         }
1204
1205         construct_reply_common(req, inbuf, *outbuf);
1206         srv_set_message(*outbuf, num_words, num_bytes, false);
1207         /*
1208          * Zero out the word area, the caller has to take care of the bcc area
1209          * himself
1210          */
1211         if (num_words != 0) {
1212                 memset(*outbuf + smb_vwv0, 0, num_words*2);
1213         }
1214
1215         return true;
1216 }
1217
1218 void reply_outbuf(struct smb_request *req, uint8 num_words, uint32 num_bytes)
1219 {
1220         char *outbuf;
1221         if (!create_outbuf(req, req, (char *)req->inbuf, &outbuf, num_words,
1222                            num_bytes)) {
1223                 smb_panic("could not allocate output buffer\n");
1224         }
1225         req->outbuf = (uint8_t *)outbuf;
1226 }
1227
1228
1229 /*******************************************************************
1230  Dump a packet to a file.
1231 ********************************************************************/
1232
1233 static void smb_dump(const char *name, int type, const char *data, ssize_t len)
1234 {
1235         int fd, i;
1236         char *fname = NULL;
1237         if (DEBUGLEVEL < 50) {
1238                 return;
1239         }
1240
1241         if (len < 4) len = smb_len(data)+4;
1242         for (i=1;i<100;i++) {
1243                 if (asprintf(&fname, "/tmp/%s.%d.%s", name, i,
1244                              type ? "req" : "resp") == -1) {
1245                         return;
1246                 }
1247                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
1248                 if (fd != -1 || errno != EEXIST) break;
1249         }
1250         if (fd != -1) {
1251                 ssize_t ret = write(fd, data, len);
1252                 if (ret != len)
1253                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
1254                 close(fd);
1255                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
1256         }
1257         SAFE_FREE(fname);
1258 }
1259
1260 /****************************************************************************
1261  Prepare everything for calling the actual request function, and potentially
1262  call the request function via the "new" interface.
1263
1264  Return False if the "legacy" function needs to be called, everything is
1265  prepared.
1266
1267  Return True if we're done.
1268
1269  I know this API sucks, but it is the one with the least code change I could
1270  find.
1271 ****************************************************************************/
1272
1273 static connection_struct *switch_message(uint8 type, struct smb_request *req, int size)
1274 {
1275         int flags;
1276         uint16 session_tag;
1277         connection_struct *conn = NULL;
1278
1279         errno = 0;
1280
1281         /* Make sure this is an SMB packet. smb_size contains NetBIOS header
1282          * so subtract 4 from it. */
1283         if (!valid_smb_header(req->inbuf)
1284             || (size < (smb_size - 4))) {
1285                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",
1286                          smb_len(req->inbuf)));
1287                 exit_server_cleanly("Non-SMB packet");
1288         }
1289
1290         if (smb_messages[type].fn == NULL) {
1291                 DEBUG(0,("Unknown message type %d!\n",type));
1292                 smb_dump("Unknown", 1, (char *)req->inbuf, size);
1293                 reply_unknown_new(req, type);
1294                 return NULL;
1295         }
1296
1297         flags = smb_messages[type].flags;
1298
1299         /* In share mode security we must ignore the vuid. */
1300         session_tag = (lp_security() == SEC_SHARE)
1301                 ? UID_FIELD_INVALID : req->vuid;
1302         conn = req->conn;
1303
1304         DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n", smb_fn_name(type),
1305                  (int)sys_getpid(), (unsigned long)conn));
1306
1307         smb_dump(smb_fn_name(type), 1, (char *)req->inbuf, size);
1308
1309         /* Ensure this value is replaced in the incoming packet. */
1310         SSVAL(req->inbuf,smb_uid,session_tag);
1311
1312         /*
1313          * Ensure the correct username is in current_user_info.  This is a
1314          * really ugly bugfix for problems with multiple session_setup_and_X's
1315          * being done and allowing %U and %G substitutions to work correctly.
1316          * There is a reason this code is done here, don't move it unless you
1317          * know what you're doing... :-).
1318          * JRA.
1319          */
1320
1321         if (session_tag != last_session_tag) {
1322                 user_struct *vuser = NULL;
1323
1324                 last_session_tag = session_tag;
1325                 if(session_tag != UID_FIELD_INVALID) {
1326                         vuser = get_valid_user_struct(session_tag);
1327                         if (vuser) {
1328                                 set_current_user_info(
1329                                         vuser->server_info->sanitized_username,
1330                                         vuser->server_info->unix_name,
1331                                         pdb_get_domain(vuser->server_info
1332                                                        ->sam_account));
1333                         }
1334                 }
1335         }
1336
1337         /* Does this call need to be run as the connected user? */
1338         if (flags & AS_USER) {
1339
1340                 /* Does this call need a valid tree connection? */
1341                 if (!conn) {
1342                         /*
1343                          * Amazingly, the error code depends on the command
1344                          * (from Samba4).
1345                          */
1346                         if (type == SMBntcreateX) {
1347                                 reply_nterror(req, NT_STATUS_INVALID_HANDLE);
1348                         } else {
1349                                 reply_doserror(req, ERRSRV, ERRinvnid);
1350                         }
1351                         return NULL;
1352                 }
1353
1354                 if (!change_to_user(conn,session_tag)) {
1355                         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRbaduid));
1356                         remove_deferred_open_smb_message(req->mid);
1357                         return conn;
1358                 }
1359
1360                 /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
1361
1362                 /* Does it need write permission? */
1363                 if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
1364                         reply_nterror(req, NT_STATUS_MEDIA_WRITE_PROTECTED);
1365                         return conn;
1366                 }
1367
1368                 /* IPC services are limited */
1369                 if (IS_IPC(conn) && !(flags & CAN_IPC)) {
1370                         reply_doserror(req, ERRSRV,ERRaccess);
1371                         return conn;
1372                 }
1373         } else {
1374                 /* This call needs to be run as root */
1375                 change_to_root_user();
1376         }
1377
1378         /* load service specific parameters */
1379         if (conn) {
1380                 if (req->encrypted) {
1381                         conn->encrypted_tid = true;
1382                         /* encrypted required from now on. */
1383                         conn->encrypt_level = Required;
1384                 } else if (ENCRYPTION_REQUIRED(conn)) {
1385                         if (req->cmd != SMBtrans2 && req->cmd != SMBtranss2) {
1386                                 exit_server_cleanly("encryption required "
1387                                         "on connection");
1388                                 return conn;
1389                         }
1390                 }
1391
1392                 if (!set_current_service(conn,SVAL(req->inbuf,smb_flg),
1393                                          (flags & (AS_USER|DO_CHDIR)
1394                                           ?True:False))) {
1395                         reply_doserror(req, ERRSRV, ERRaccess);
1396                         return conn;
1397                 }
1398                 conn->num_smb_operations++;
1399         }
1400
1401         /* does this protocol need to be run as guest? */
1402         if ((flags & AS_GUEST)
1403             && (!change_to_guest() ||
1404                 !check_access(smbd_server_fd(), lp_hostsallow(-1),
1405                               lp_hostsdeny(-1)))) {
1406                 reply_doserror(req, ERRSRV, ERRaccess);
1407                 return conn;
1408         }
1409
1410         smb_messages[type].fn(req);
1411         return req->conn;
1412 }
1413
1414 /****************************************************************************
1415  Construct a reply to the incoming packet.
1416 ****************************************************************************/
1417
1418 static void construct_reply(char *inbuf, int size, size_t unread_bytes, bool encrypted)
1419 {
1420         connection_struct *conn;
1421         struct smb_request *req;
1422
1423         chain_size = 0;
1424
1425         if (!(req = talloc(talloc_tos(), struct smb_request))) {
1426                 smb_panic("could not allocate smb_request");
1427         }
1428         init_smb_request(req, (uint8 *)inbuf, unread_bytes, encrypted);
1429         req->inbuf  = (uint8_t *)talloc_move(req, &inbuf);
1430
1431         conn = switch_message(req->cmd, req, size);
1432
1433         if (req->unread_bytes) {
1434                 /* writeX failed. drain socket. */
1435                 if (drain_socket(smbd_server_fd(), req->unread_bytes) !=
1436                                 req->unread_bytes) {
1437                         smb_panic("failed to drain pending bytes");
1438                 }
1439                 req->unread_bytes = 0;
1440         }
1441
1442         if (req->outbuf == NULL) {
1443                 return;
1444         }
1445
1446         if (CVAL(req->outbuf,0) == 0) {
1447                 show_msg((char *)req->outbuf);
1448         }
1449
1450         if (!srv_send_smb(smbd_server_fd(),
1451                         (char *)req->outbuf,
1452                         IS_CONN_ENCRYPTED(conn)||req->encrypted)) {
1453                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1454         }
1455
1456         TALLOC_FREE(req);
1457
1458         return;
1459 }
1460
1461 /****************************************************************************
1462  Process an smb from the client
1463 ****************************************************************************/
1464
1465 static void process_smb(struct smbd_server_connection *conn,
1466                         uint8_t *inbuf, size_t nread, size_t unread_bytes,
1467                         bool encrypted)
1468 {
1469         int msg_type = CVAL(inbuf,0);
1470
1471         DO_PROFILE_INC(smb_count);
1472
1473         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type,
1474                     smb_len(inbuf) ) );
1475         DEBUG( 3, ( "Transaction %d of length %d (%u toread)\n", trans_num,
1476                                 (int)nread,
1477                                 (unsigned int)unread_bytes ));
1478
1479         if (msg_type != 0) {
1480                 /*
1481                  * NetBIOS session request, keepalive, etc.
1482                  */
1483                 reply_special((char *)inbuf);
1484                 goto done;
1485         }
1486
1487         show_msg((char *)inbuf);
1488
1489         construct_reply((char *)inbuf,nread,unread_bytes,encrypted);
1490
1491         trans_num++;
1492
1493 done:
1494         conn->num_requests++;
1495
1496         /* The timeout_processing function isn't run nearly
1497            often enough to implement 'max log size' without
1498            overrunning the size of the file by many megabytes.
1499            This is especially true if we are running at debug
1500            level 10.  Checking every 50 SMBs is a nice
1501            tradeoff of performance vs log file size overrun. */
1502
1503         if ((conn->num_requests % 50) == 0 &&
1504             need_to_check_log_size()) {
1505                 change_to_root_user();
1506                 check_log_size();
1507         }
1508 }
1509
1510 /****************************************************************************
1511  Return a string containing the function name of a SMB command.
1512 ****************************************************************************/
1513
1514 const char *smb_fn_name(int type)
1515 {
1516         const char *unknown_name = "SMBunknown";
1517
1518         if (smb_messages[type].name == NULL)
1519                 return(unknown_name);
1520
1521         return(smb_messages[type].name);
1522 }
1523
1524 /****************************************************************************
1525  Helper functions for contruct_reply.
1526 ****************************************************************************/
1527
1528 void add_to_common_flags2(uint32 v)
1529 {
1530         common_flags2 |= v;
1531 }
1532
1533 void remove_from_common_flags2(uint32 v)
1534 {
1535         common_flags2 &= ~v;
1536 }
1537
1538 static void construct_reply_common(struct smb_request *req, const char *inbuf,
1539                                    char *outbuf)
1540 {
1541         srv_set_message(outbuf,0,0,false);
1542         
1543         SCVAL(outbuf, smb_com, req->cmd);
1544         SIVAL(outbuf,smb_rcls,0);
1545         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES)); 
1546         SSVAL(outbuf,smb_flg2,
1547                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1548                 common_flags2);
1549         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1550
1551         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1552         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1553         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1554         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1555 }
1556
1557 void construct_reply_common_req(struct smb_request *req, char *outbuf)
1558 {
1559         construct_reply_common(req, (char *)req->inbuf, outbuf);
1560 }
1561
1562 /*
1563  * How many bytes have we already accumulated up to the current wct field
1564  * offset?
1565  */
1566
1567 size_t req_wct_ofs(struct smb_request *req)
1568 {
1569         size_t buf_size;
1570
1571         if (req->chain_outbuf == NULL) {
1572                 return smb_wct - 4;
1573         }
1574         buf_size = talloc_get_size(req->chain_outbuf);
1575         if ((buf_size % 4) != 0) {
1576                 buf_size += (4 - (buf_size % 4));
1577         }
1578         return buf_size - 4;
1579 }
1580
1581 /*
1582  * Hack around reply_nterror & friends not being aware of chained requests,
1583  * generating illegal (i.e. wct==0) chain replies.
1584  */
1585
1586 static void fixup_chain_error_packet(struct smb_request *req)
1587 {
1588         uint8_t *outbuf = req->outbuf;
1589         req->outbuf = NULL;
1590         reply_outbuf(req, 2, 0);
1591         memcpy(req->outbuf, outbuf, smb_wct);
1592         TALLOC_FREE(outbuf);
1593         SCVAL(req->outbuf, smb_vwv0, 0xff);
1594 }
1595
1596 /****************************************************************************
1597  Construct a chained reply and add it to the already made reply
1598 ****************************************************************************/
1599
1600 void chain_reply(struct smb_request *req)
1601 {
1602         size_t smblen = smb_len(req->inbuf);
1603         size_t already_used, length_needed;
1604         uint8_t chain_cmd;
1605         uint32_t chain_offset;  /* uint32_t to avoid overflow */
1606
1607         uint8_t wct;
1608         uint16_t *vwv;
1609         uint16_t buflen;
1610         uint8_t *buf;
1611
1612         if (IVAL(req->outbuf, smb_rcls) != 0) {
1613                 fixup_chain_error_packet(req);
1614         }
1615
1616         /*
1617          * Any of the AndX requests and replies have at least a wct of
1618          * 2. vwv[0] is the next command, vwv[1] is the offset from the
1619          * beginning of the SMB header to the next wct field.
1620          *
1621          * None of the AndX requests put anything valuable in vwv[0] and [1],
1622          * so we can overwrite it here to form the chain.
1623          */
1624
1625         if ((req->wct < 2) || (CVAL(req->outbuf, smb_wct) < 2)) {
1626                 goto error;
1627         }
1628
1629         /*
1630          * Here we assume that this is the end of the chain. For that we need
1631          * to set "next command" to 0xff and the offset to 0. If we later find
1632          * more commands in the chain, this will be overwritten again.
1633          */
1634
1635         SCVAL(req->outbuf, smb_vwv0, 0xff);
1636         SCVAL(req->outbuf, smb_vwv0+1, 0);
1637         SSVAL(req->outbuf, smb_vwv1, 0);
1638
1639         if (req->chain_outbuf == NULL) {
1640                 /*
1641                  * In req->chain_outbuf we collect all the replies. Start the
1642                  * chain by copying in the first reply.
1643                  *
1644                  * We do the realloc because later on we depend on
1645                  * talloc_get_size to determine the length of
1646                  * chain_outbuf. The reply_xxx routines might have
1647                  * over-allocated (reply_pipe_read_and_X used to be such an
1648                  * example).
1649                  */
1650                 req->chain_outbuf = TALLOC_REALLOC_ARRAY(
1651                         req, req->outbuf, uint8_t, smb_len(req->outbuf) + 4);
1652                 if (req->chain_outbuf == NULL) {
1653                         goto error;
1654                 }
1655                 req->outbuf = NULL;
1656         } else {
1657                 if (!smb_splice_chain(&req->chain_outbuf,
1658                                       CVAL(req->outbuf, smb_com),
1659                                       CVAL(req->outbuf, smb_wct),
1660                                       (uint16_t *)(req->outbuf + smb_vwv),
1661                                       0, smb_buflen(req->outbuf),
1662                                       (uint8_t *)smb_buf(req->outbuf))) {
1663                         goto error;
1664                 }
1665                 TALLOC_FREE(req->outbuf);
1666         }
1667
1668         /*
1669          * We use the old request's vwv field to grab the next chained command
1670          * and offset into the chained fields.
1671          */
1672
1673         chain_cmd = CVAL(req->vwv+0, 0);
1674         chain_offset = SVAL(req->vwv+1, 0);
1675
1676         if (chain_cmd == 0xff) {
1677                 /*
1678                  * End of chain, no more requests from the client. So ship the
1679                  * replies.
1680                  */
1681                 smb_setlen((char *)(req->chain_outbuf),
1682                            talloc_get_size(req->chain_outbuf) - 4);
1683                 if (!srv_send_smb(smbd_server_fd(), (char *)req->chain_outbuf,
1684                                   IS_CONN_ENCRYPTED(req->conn)
1685                                   ||req->encrypted)) {
1686                         exit_server_cleanly("chain_reply: srv_send_smb "
1687                                             "failed.");
1688                 }
1689                 return;
1690         }
1691
1692         /*
1693          * Check if the client tries to fool us. The request so far uses the
1694          * space to the end of the byte buffer in the request just
1695          * processed. The chain_offset can't point into that area. If that was
1696          * the case, we could end up with an endless processing of the chain,
1697          * we would always handle the same request.
1698          */
1699
1700         already_used = PTR_DIFF(req->buf+req->buflen, smb_base(req->inbuf));
1701         if (chain_offset < already_used) {
1702                 goto error;
1703         }
1704
1705         /*
1706          * Next check: Make sure the chain offset does not point beyond the
1707          * overall smb request length.
1708          */
1709
1710         length_needed = chain_offset+1; /* wct */
1711         if (length_needed > smblen) {
1712                 goto error;
1713         }
1714
1715         /*
1716          * Now comes the pointer magic. Goal here is to set up req->vwv and
1717          * req->buf correctly again to be able to call the subsequent
1718          * switch_message(). The chain offset (the former vwv[1]) points at
1719          * the new wct field.
1720          */
1721
1722         wct = CVAL(smb_base(req->inbuf), chain_offset);
1723
1724         /*
1725          * Next consistency check: Make the new vwv array fits in the overall
1726          * smb request.
1727          */
1728
1729         length_needed += (wct+1)*sizeof(uint16_t); /* vwv+buflen */
1730         if (length_needed > smblen) {
1731                 goto error;
1732         }
1733         vwv = (uint16_t *)(smb_base(req->inbuf) + chain_offset + 1);
1734
1735         /*
1736          * Now grab the new byte buffer....
1737          */
1738
1739         buflen = SVAL(vwv+wct, 0);
1740
1741         /*
1742          * .. and check that it fits.
1743          */
1744
1745         length_needed += buflen;
1746         if (length_needed > smblen) {
1747                 goto error;
1748         }
1749         buf = (uint8_t *)(vwv+wct+1);
1750
1751         req->cmd = chain_cmd;
1752         req->wct = wct;
1753         req->vwv = vwv;
1754         req->buflen = buflen;
1755         req->buf = buf;
1756
1757         switch_message(chain_cmd, req, smblen);
1758
1759         if (req->outbuf == NULL) {
1760                 /*
1761                  * This happens if the chained command has suspended itself or
1762                  * if it has called srv_send_smb() itself.
1763                  */
1764                 return;
1765         }
1766
1767         /*
1768          * We end up here if the chained command was not itself chained or
1769          * suspended, but for example a close() command. We now need to splice
1770          * the chained commands' outbuf into the already built up chain_outbuf
1771          * and ship the result.
1772          */
1773         goto done;
1774
1775  error:
1776         /*
1777          * We end up here if there's any error in the chain syntax. Report a
1778          * DOS error, just like Windows does.
1779          */
1780         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRerror));
1781         fixup_chain_error_packet(req);
1782
1783  done:
1784         if (!smb_splice_chain(&req->chain_outbuf,
1785                               CVAL(req->outbuf, smb_com),
1786                               CVAL(req->outbuf, smb_wct),
1787                               (uint16_t *)(req->outbuf + smb_vwv),
1788                               0, smb_buflen(req->outbuf),
1789                               (uint8_t *)smb_buf(req->outbuf))) {
1790                 exit_server_cleanly("chain_reply: smb_splice_chain failed\n");
1791         }
1792         TALLOC_FREE(req->outbuf);
1793
1794         smb_setlen((char *)(req->chain_outbuf),
1795                    talloc_get_size(req->chain_outbuf) - 4);
1796
1797         show_msg((char *)(req->chain_outbuf));
1798
1799         if (!srv_send_smb(smbd_server_fd(), (char *)req->chain_outbuf,
1800                           IS_CONN_ENCRYPTED(req->conn)||req->encrypted)) {
1801                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1802         }
1803 }
1804
1805 /****************************************************************************
1806  Check if services need reloading.
1807 ****************************************************************************/
1808
1809 void check_reload(time_t t)
1810 {
1811         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1812
1813         if(last_smb_conf_reload_time == 0) {
1814                 last_smb_conf_reload_time = t;
1815                 /* Our printing subsystem might not be ready at smbd start up.
1816                    Then no printer is available till the first printers check
1817                    is performed.  A lower initial interval circumvents this. */
1818                 if ( printcap_cache_time > 60 )
1819                         last_printer_reload_time = t - printcap_cache_time + 60;
1820                 else
1821                         last_printer_reload_time = t;
1822         }
1823
1824         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1825                 /* randomize over 60 second the printcap reload to avoid all
1826                  * process hitting cupsd at the same time */
1827                 int time_range = 60;
1828
1829                 last_printer_reload_time += random() % time_range;
1830                 mypid = getpid();
1831         }
1832
1833         if (reload_after_sighup || (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK)) {
1834                 reload_services(True);
1835                 reload_after_sighup = False;
1836                 last_smb_conf_reload_time = t;
1837         }
1838
1839         /* 'printcap cache time = 0' disable the feature */
1840         
1841         if ( printcap_cache_time != 0 )
1842         { 
1843                 /* see if it's time to reload or if the clock has been set back */
1844                 
1845                 if ( (t >= last_printer_reload_time+printcap_cache_time) 
1846                         || (t-last_printer_reload_time  < 0) ) 
1847                 {
1848                         DEBUG( 3,( "Printcap cache time expired.\n"));
1849                         reload_printers();
1850                         last_printer_reload_time = t;
1851                 }
1852         }
1853 }
1854
1855 static void smbd_server_connection_write_handler(struct smbd_server_connection *conn)
1856 {
1857         /* TODO: make write nonblocking */
1858 }
1859
1860 static void smbd_server_connection_read_handler(struct smbd_server_connection *conn)
1861 {
1862         uint8_t *inbuf = NULL;
1863         size_t inbuf_len = 0;
1864         size_t unread_bytes = 0;
1865         bool encrypted = false;
1866         TALLOC_CTX *mem_ctx = talloc_tos();
1867         NTSTATUS status;
1868
1869         /* TODO: make this completely nonblocking */
1870
1871         status = receive_smb_talloc(mem_ctx, smbd_server_fd(),
1872                                     (char **)(void *)&inbuf,
1873                                     0, /* timeout */
1874                                     &unread_bytes,
1875                                     &encrypted,
1876                                     &inbuf_len);
1877         if (NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
1878                 goto process;
1879         }
1880         if (NT_STATUS_IS_ERR(status)) {
1881                 exit_server_cleanly("failed to receive smb request");
1882         }
1883         if (!NT_STATUS_IS_OK(status)) {
1884                 return;
1885         }
1886
1887 process:
1888         process_smb(conn, inbuf, inbuf_len, unread_bytes, encrypted);
1889 }
1890
1891 static void smbd_server_connection_handler(struct event_context *ev,
1892                                            struct fd_event *fde,
1893                                            uint16_t flags,
1894                                            void *private_data)
1895 {
1896         struct smbd_server_connection *conn = talloc_get_type(private_data,
1897                                               struct smbd_server_connection);
1898
1899         if (flags & EVENT_FD_WRITE) {
1900                 smbd_server_connection_write_handler(conn);
1901         } else if (flags & EVENT_FD_READ) {
1902                 smbd_server_connection_read_handler(conn);
1903         }
1904 }
1905
1906
1907 /****************************************************************************
1908 received when we should release a specific IP
1909 ****************************************************************************/
1910 static void release_ip(const char *ip, void *priv)
1911 {
1912         char addr[INET6_ADDRSTRLEN];
1913
1914         if (strcmp(client_socket_addr(get_client_fd(),addr,sizeof(addr)), ip) == 0) {
1915                 /* we can't afford to do a clean exit - that involves
1916                    database writes, which would potentially mean we
1917                    are still running after the failover has finished -
1918                    we have to get rid of this process ID straight
1919                    away */
1920                 DEBUG(0,("Got release IP message for our IP %s - exiting immediately\n",
1921                         ip));
1922                 /* note we must exit with non-zero status so the unclean handler gets
1923                    called in the parent, so that the brl database is tickled */
1924                 _exit(1);
1925         }
1926 }
1927
1928 static void msg_release_ip(struct messaging_context *msg_ctx, void *private_data,
1929                            uint32_t msg_type, struct server_id server_id, DATA_BLOB *data)
1930 {
1931         release_ip((char *)data->data, NULL);
1932 }
1933
1934 #ifdef CLUSTER_SUPPORT
1935 static int client_get_tcp_info(struct sockaddr_storage *server,
1936                                struct sockaddr_storage *client)
1937 {
1938         socklen_t length;
1939         if (server_fd == -1) {
1940                 return -1;
1941         }
1942         length = sizeof(*server);
1943         if (getsockname(server_fd, (struct sockaddr *)server, &length) != 0) {
1944                 return -1;
1945         }
1946         length = sizeof(*client);
1947         if (getpeername(server_fd, (struct sockaddr *)client, &length) != 0) {
1948                 return -1;
1949         }
1950         return 0;
1951 }
1952 #endif
1953
1954 /*
1955  * Send keepalive packets to our client
1956  */
1957 static bool keepalive_fn(const struct timeval *now, void *private_data)
1958 {
1959         if (!send_keepalive(smbd_server_fd())) {
1960                 DEBUG( 2, ( "Keepalive failed - exiting.\n" ) );
1961                 return False;
1962         }
1963         return True;
1964 }
1965
1966 /*
1967  * Do the recurring check if we're idle
1968  */
1969 static bool deadtime_fn(const struct timeval *now, void *private_data)
1970 {
1971         if ((conn_num_open() == 0)
1972             || (conn_idle_all(now->tv_sec))) {
1973                 DEBUG( 2, ( "Closing idle connection\n" ) );
1974                 messaging_send(smbd_messaging_context(), procid_self(),
1975                                MSG_SHUTDOWN, &data_blob_null);
1976                 return False;
1977         }
1978
1979         return True;
1980 }
1981
1982 /*
1983  * Do the recurring log file and smb.conf reload checks.
1984  */
1985
1986 static bool housekeeping_fn(const struct timeval *now, void *private_data)
1987 {
1988         change_to_root_user();
1989
1990         /* update printer queue caches if necessary */
1991         update_monitored_printq_cache();
1992
1993         /* check if we need to reload services */
1994         check_reload(time(NULL));
1995
1996         /* Change machine password if neccessary. */
1997         attempt_machine_password_change();
1998
1999         /*
2000          * Force a log file check.
2001          */
2002         force_check_log_size();
2003         check_log_size();
2004         return true;
2005 }
2006
2007 /****************************************************************************
2008  Process commands from the client
2009 ****************************************************************************/
2010
2011 void smbd_process(void)
2012 {
2013         TALLOC_CTX *frame = talloc_stackframe();
2014         char remaddr[INET6_ADDRSTRLEN];
2015
2016         smbd_server_conn = talloc_zero(smbd_event_context(), struct smbd_server_connection);
2017         if (!smbd_server_conn) {
2018                 exit_server("failed to create smbd_server_connection");
2019         }
2020
2021         /* Ensure child is set to blocking mode */
2022         set_blocking(smbd_server_fd(),True);
2023
2024         set_socket_options(smbd_server_fd(),"SO_KEEPALIVE");
2025         set_socket_options(smbd_server_fd(), lp_socket_options());
2026
2027         /* this is needed so that we get decent entries
2028            in smbstatus for port 445 connects */
2029         set_remote_machine_name(get_peer_addr(smbd_server_fd(),
2030                                               remaddr,
2031                                               sizeof(remaddr)),
2032                                               false);
2033         reload_services(true);
2034
2035         /*
2036          * Before the first packet, check the global hosts allow/ hosts deny
2037          * parameters before doing any parsing of packets passed to us by the
2038          * client. This prevents attacks on our parsing code from hosts not in
2039          * the hosts allow list.
2040          */
2041
2042         if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
2043                           lp_hostsdeny(-1))) {
2044                 char addr[INET6_ADDRSTRLEN];
2045
2046                 /*
2047                  * send a negative session response "not listening on calling
2048                  * name"
2049                  */
2050                 unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
2051                 DEBUG( 1, ("Connection denied from %s\n",
2052                            client_addr(get_client_fd(),addr,sizeof(addr)) ) );
2053                 (void)srv_send_smb(smbd_server_fd(),(char *)buf,false);
2054                 exit_server_cleanly("connection denied");
2055         }
2056
2057         static_init_rpc;
2058
2059         init_modules();
2060
2061         if (!init_account_policy()) {
2062                 exit_server("Could not open account policy tdb.\n");
2063         }
2064
2065         if (*lp_rootdir()) {
2066                 if (chroot(lp_rootdir()) != 0) {
2067                         DEBUG(0,("Failed changed root to %s\n", lp_rootdir()));
2068                         exit_server("Failed to chroot()");
2069                 }
2070                 DEBUG(0,("Changed root to %s\n", lp_rootdir()));
2071         }
2072
2073         /* Setup oplocks */
2074         if (!init_oplocks(smbd_messaging_context()))
2075                 exit_server("Failed to init oplocks");
2076
2077         /* Setup aio signal handler. */
2078         initialize_async_io_handler();
2079
2080         /* register our message handlers */
2081         messaging_register(smbd_messaging_context(), NULL,
2082                            MSG_SMB_FORCE_TDIS, msg_force_tdis);
2083         messaging_register(smbd_messaging_context(), NULL,
2084                            MSG_SMB_RELEASE_IP, msg_release_ip);
2085         messaging_register(smbd_messaging_context(), NULL,
2086                            MSG_SMB_CLOSE_FILE, msg_close_file);
2087
2088         if ((lp_keepalive() != 0)
2089             && !(event_add_idle(smbd_event_context(), NULL,
2090                                 timeval_set(lp_keepalive(), 0),
2091                                 "keepalive", keepalive_fn,
2092                                 NULL))) {
2093                 DEBUG(0, ("Could not add keepalive event\n"));
2094                 exit(1);
2095         }
2096
2097         if (!(event_add_idle(smbd_event_context(), NULL,
2098                              timeval_set(IDLE_CLOSED_TIMEOUT, 0),
2099                              "deadtime", deadtime_fn, NULL))) {
2100                 DEBUG(0, ("Could not add deadtime event\n"));
2101                 exit(1);
2102         }
2103
2104         if (!(event_add_idle(smbd_event_context(), NULL,
2105                              timeval_set(SMBD_SELECT_TIMEOUT, 0),
2106                              "housekeeping", housekeeping_fn, NULL))) {
2107                 DEBUG(0, ("Could not add housekeeping event\n"));
2108                 exit(1);
2109         }
2110
2111 #ifdef CLUSTER_SUPPORT
2112
2113         if (lp_clustering()) {
2114                 /*
2115                  * We need to tell ctdb about our client's TCP
2116                  * connection, so that for failover ctdbd can send
2117                  * tickle acks, triggering a reconnection by the
2118                  * client.
2119                  */
2120
2121                 struct sockaddr_storage srv, clnt;
2122
2123                 if (client_get_tcp_info(&srv, &clnt) == 0) {
2124
2125                         NTSTATUS status;
2126
2127                         status = ctdbd_register_ips(
2128                                 messaging_ctdbd_connection(),
2129                                 &srv, &clnt, release_ip, NULL);
2130
2131                         if (!NT_STATUS_IS_OK(status)) {
2132                                 DEBUG(0, ("ctdbd_register_ips failed: %s\n",
2133                                           nt_errstr(status)));
2134                         }
2135                 } else
2136                 {
2137                         DEBUG(0,("Unable to get tcp info for "
2138                                  "CTDB_CONTROL_TCP_CLIENT: %s\n",
2139                                  strerror(errno)));
2140                 }
2141         }
2142
2143 #endif
2144
2145         max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
2146
2147         smbd_server_conn->fde = event_add_fd(smbd_event_context(),
2148                                              smbd_server_conn,
2149                                              smbd_server_fd(),
2150                                              EVENT_FD_READ,
2151                                              smbd_server_connection_handler,
2152                                              smbd_server_conn);
2153         if (!smbd_server_conn->fde) {
2154                 exit_server("failed to create smbd_server_connection fde");
2155         }
2156
2157         TALLOC_FREE(frame);
2158
2159         while (True) {
2160                 NTSTATUS status;
2161
2162                 frame = talloc_stackframe_pool(8192);
2163
2164                 errno = 0;
2165
2166                 status = smbd_server_connection_loop_once(smbd_server_conn);
2167                 if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY) &&
2168                     !NT_STATUS_IS_OK(status)) {
2169                         DEBUG(3, ("smbd_server_connection_loop_once failed: %s,"
2170                                   " exiting\n", nt_errstr(status)));
2171                         break;
2172                 }
2173
2174                 TALLOC_FREE(frame);
2175         }
2176
2177         exit_server_cleanly(NULL);
2178 }