a202c1fa87a131c5bd2821722cf519a7ebee7bfd
[samba.git] / source / 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
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 2 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, write to the Free Software
19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 */
21
22 #include "includes.h"
23
24 uint16 global_smbpid;
25 extern int keepalive;
26 extern struct auth_context *negprot_global_auth_context;
27 extern int smb_echo_count;
28
29 static char *InBuffer = NULL;
30 static char *OutBuffer = NULL;
31 static char *current_inbuf = NULL;
32
33 /* 
34  * Size of data we can send to client. Set
35  *  by the client for all protocols above CORE.
36  *  Set by us for CORE protocol.
37  */
38 int max_send = BUFFER_SIZE;
39 /*
40  * Size of the data we can receive. Set by us.
41  * Can be modified by the max xmit parameter.
42  */
43 int max_recv = BUFFER_SIZE;
44
45 extern int last_message;
46 extern int smb_read_error;
47 SIG_ATOMIC_T reload_after_sighup = 0;
48 SIG_ATOMIC_T got_sig_term = 0;
49 extern BOOL global_machine_password_needs_changing;
50 extern int max_send;
51
52 /****************************************************************************
53  Function to return the current request mid from Inbuffer.
54 ****************************************************************************/
55
56 uint16 get_current_mid(void)
57 {
58         return SVAL(InBuffer,smb_mid);
59 }
60
61 /****************************************************************************
62  structure to hold a linked list of queued messages.
63  for processing.
64 ****************************************************************************/
65
66 static struct pending_message_list *deferred_open_queue;
67
68 /****************************************************************************
69  Function to push a message onto the tail of a linked list of smb messages ready
70  for processing.
71 ****************************************************************************/
72
73 static BOOL push_queued_message(char *buf, int msg_len,
74                                 struct timeval request_time,
75                                 struct timeval end_time,
76                                 char *private_data, size_t private_len)
77 {
78         struct pending_message_list *tmp_msg;
79         struct pending_message_list *msg;
80
81         msg = TALLOC_ZERO_P(NULL, struct pending_message_list);
82
83         if(msg == NULL) {
84                 DEBUG(0,("push_message: malloc fail (1)\n"));
85                 return False;
86         }
87
88         msg->buf = data_blob_talloc(msg, buf, msg_len);
89         if(msg->buf.data == NULL) {
90                 DEBUG(0,("push_message: malloc fail (2)\n"));
91                 TALLOC_FREE(msg);
92                 return False;
93         }
94
95         msg->request_time = request_time;
96         msg->end_time = end_time;
97
98         if (private_data) {
99                 msg->private_data = data_blob_talloc(msg, private_data,
100                                                      private_len);
101                 if (msg->private_data.data == NULL) {
102                         DEBUG(0,("push_message: malloc fail (3)\n"));
103                         TALLOC_FREE(msg);
104                         return False;
105                 }
106         }
107
108         DLIST_ADD_END(deferred_open_queue, msg, tmp_msg);
109
110         DEBUG(10,("push_message: pushed message length %u on "
111                   "deferred_open_queue\n", (unsigned int)msg_len));
112
113         return True;
114 }
115
116 /****************************************************************************
117  Function to delete a sharing violation open message by mid.
118 ****************************************************************************/
119
120 void remove_deferred_open_smb_message(uint16 mid)
121 {
122         struct pending_message_list *pml;
123
124         for (pml = deferred_open_queue; pml; pml = pml->next) {
125                 if (mid == SVAL(pml->buf.data,smb_mid)) {
126                         DEBUG(10,("remove_sharing_violation_open_smb_message: "
127                                   "deleting mid %u len %u\n",
128                                   (unsigned int)mid,
129                                   (unsigned int)pml->buf.length ));
130                         DLIST_REMOVE(deferred_open_queue, pml);
131                         TALLOC_FREE(pml);
132                         return;
133                 }
134         }
135 }
136
137 /****************************************************************************
138  Move a sharing violation open retry message to the front of the list and
139  schedule it for immediate processing.
140 ****************************************************************************/
141
142 void schedule_deferred_open_smb_message(uint16 mid)
143 {
144         struct pending_message_list *pml;
145         int i = 0;
146
147         for (pml = deferred_open_queue; pml; pml = pml->next) {
148                 uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
149                 DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
150                         (unsigned int)msg_mid ));
151                 if (mid == msg_mid) {
152                         DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
153                                 mid ));
154                         pml->end_time.tv_sec = 0;
155                         pml->end_time.tv_usec = 0;
156                         DLIST_PROMOTE(deferred_open_queue, pml);
157                         return;
158                 }
159         }
160
161         DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
162                 mid ));
163 }
164
165 /****************************************************************************
166  Return true if this mid is on the deferred queue.
167 ****************************************************************************/
168
169 BOOL open_was_deferred(uint16 mid)
170 {
171         struct pending_message_list *pml;
172
173         for (pml = deferred_open_queue; pml; pml = pml->next) {
174                 if (SVAL(pml->buf.data,smb_mid) == mid) {
175                         return True;
176                 }
177         }
178         return False;
179 }
180
181 /****************************************************************************
182  Return the message queued by this mid.
183 ****************************************************************************/
184
185 struct pending_message_list *get_open_deferred_message(uint16 mid)
186 {
187         struct pending_message_list *pml;
188
189         for (pml = deferred_open_queue; pml; pml = pml->next) {
190                 if (SVAL(pml->buf.data,smb_mid) == mid) {
191                         return pml;
192                 }
193         }
194         return NULL;
195 }
196
197 /****************************************************************************
198  Function to push a deferred open smb message onto a linked list of local smb
199  messages ready for processing.
200 ****************************************************************************/
201
202 BOOL push_deferred_smb_message(uint16 mid,
203                                struct timeval request_time,
204                                struct timeval timeout,
205                                char *private_data, size_t priv_len)
206 {
207         struct timeval end_time;
208
209         end_time = timeval_sum(&request_time, &timeout);
210
211         DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
212                   "timeout time [%u.%06u]\n",
213                   (unsigned int) smb_len(current_inbuf)+4, (unsigned int)mid,
214                   (unsigned int)end_time.tv_sec,
215                   (unsigned int)end_time.tv_usec));
216
217         return push_queued_message(current_inbuf, smb_len(current_inbuf)+4,
218                                    request_time, end_time,
219                                    private_data, priv_len);
220 }
221
222 struct idle_event {
223         struct timed_event *te;
224         struct timeval interval;
225         BOOL (*handler)(const struct timeval *now, void *private_data);
226         void *private_data;
227 };
228
229 static void idle_event_handler(struct timed_event *te,
230                                const struct timeval *now,
231                                void *private_data)
232 {
233         struct idle_event *event =
234                 talloc_get_type_abort(private_data, struct idle_event);
235
236         TALLOC_FREE(event->te);
237
238         if (!event->handler(now, event->private_data)) {
239                 /* Don't repeat, delete ourselves */
240                 TALLOC_FREE(event);
241                 return;
242         }
243
244         event->te = add_timed_event(event, timeval_sum(now, &event->interval),
245                                     "idle_event_handler",
246                                     idle_event_handler, event);
247
248         /* We can't do much but fail here. */
249         SMB_ASSERT(event->te != NULL);
250 }
251
252 struct idle_event *add_idle_event(TALLOC_CTX *mem_ctx,
253                                   struct timeval interval,
254                                   BOOL (*handler)(const struct timeval *now,
255                                                   void *private_data),
256                                   void *private_data)
257 {
258         struct idle_event *result;
259         struct timeval now = timeval_current();
260
261         result = TALLOC_P(mem_ctx, struct idle_event);
262         if (result == NULL) {
263                 DEBUG(0, ("talloc failed\n"));
264                 return NULL;
265         }
266
267         result->interval = interval;
268         result->handler = handler;
269         result->private_data = private_data;
270
271         result->te = add_timed_event(result, timeval_sum(&now, &interval),
272                                      "idle_event_handler",
273                                      idle_event_handler, result);
274         if (result->te == NULL) {
275                 DEBUG(0, ("add_timed_event failed\n"));
276                 TALLOC_FREE(result);
277                 return NULL;
278         }
279
280         return result;
281 }
282
283 /****************************************************************************
284  Do all async processing in here. This includes kernel oplock messages, change
285  notify events etc.
286 ****************************************************************************/
287
288 static void async_processing(fd_set *pfds)
289 {
290         DEBUG(10,("async_processing: Doing async processing.\n"));
291
292         process_aio_queue();
293
294         process_kernel_oplocks(pfds);
295
296         /* Do the aio check again after receive_local_message as it does a
297            select and may have eaten our signal. */
298         /* Is this till true? -- vl */
299         process_aio_queue();
300
301         if (got_sig_term) {
302                 exit_server_cleanly("termination signal");
303         }
304
305         /* check for async change notify events */
306         process_pending_change_notify_queue(0);
307
308         /* check for sighup processing */
309         if (reload_after_sighup) {
310                 change_to_root_user();
311                 DEBUG(1,("Reloading services after SIGHUP\n"));
312                 reload_services(False);
313                 reload_after_sighup = 0;
314         }
315 }
316
317 /****************************************************************************
318  Add a fd to the set we will be select(2)ing on.
319 ****************************************************************************/
320
321 static int select_on_fd(int fd, int maxfd, fd_set *fds)
322 {
323         if (fd != -1) {
324                 FD_SET(fd, fds);
325                 maxfd = MAX(maxfd, fd);
326         }
327
328         return maxfd;
329 }
330
331 /****************************************************************************
332   Do a select on an two fd's - with timeout. 
333
334   If a local udp message has been pushed onto the
335   queue (this can only happen during oplock break
336   processing) call async_processing()
337
338   If a pending smb message has been pushed onto the
339   queue (this can only happen during oplock break
340   processing) return this next.
341
342   If the first smbfd is ready then read an smb from it.
343   if the second (loopback UDP) fd is ready then read a message
344   from it and setup the buffer header to identify the length
345   and from address.
346   Returns False on timeout or error.
347   Else returns True.
348
349 The timeout is in milliseconds
350 ****************************************************************************/
351
352 static BOOL receive_message_or_smb(char *buffer, int buffer_len, int timeout)
353 {
354         fd_set fds;
355         int selrtn;
356         struct timeval to;
357         int maxfd = 0;
358
359         smb_read_error = 0;
360
361  again:
362
363         if (timeout >= 0) {
364                 to.tv_sec = timeout / 1000;
365                 to.tv_usec = (timeout % 1000) * 1000;
366         } else {
367                 to.tv_sec = SMBD_SELECT_TIMEOUT;
368                 to.tv_usec = 0;
369         }
370
371         /*
372          * Note that this call must be before processing any SMB
373          * messages as we need to synchronously process any messages
374          * we may have sent to ourselves from the previous SMB.
375          */
376         message_dispatch();
377
378         /*
379          * Check to see if we already have a message on the deferred open queue
380          * and it's time to schedule.
381          */
382         if(deferred_open_queue != NULL) {
383                 BOOL pop_message = False;
384                 struct pending_message_list *msg = deferred_open_queue;
385
386                 if (timeval_is_zero(&msg->end_time)) {
387                         pop_message = True;
388                 } else {
389                         struct timeval tv;
390                         SMB_BIG_INT tdif;
391
392                         GetTimeOfDay(&tv);
393                         tdif = usec_time_diff(&msg->end_time, &tv);
394                         if (tdif <= 0) {
395                                 /* Timed out. Schedule...*/
396                                 pop_message = True;
397                                 DEBUG(10,("receive_message_or_smb: queued message timed out.\n"));
398                         } else {
399                                 /* Make a more accurate select timeout. */
400                                 to.tv_sec = tdif / 1000000;
401                                 to.tv_usec = tdif % 1000000;
402                                 DEBUG(10,("receive_message_or_smb: select with timeout of [%u.%06u]\n",
403                                         (unsigned int)to.tv_sec, (unsigned int)to.tv_usec ));
404                         }
405                 }
406
407                 if (pop_message) {
408                         memcpy(buffer, msg->buf.data, MIN(buffer_len, msg->buf.length));
409   
410                         /* We leave this message on the queue so the open code can
411                            know this is a retry. */
412                         DEBUG(5,("receive_message_or_smb: returning deferred open smb message.\n"));
413                         return True;
414                 }
415         }
416
417         /*
418          * Setup the select read fd set.
419          */
420
421         FD_ZERO(&fds);
422
423         /*
424          * Ensure we process oplock break messages by preference.
425          * We have to do this before the select, after the select
426          * and if the select returns EINTR. This is due to the fact
427          * that the selects called from async_processing can eat an EINTR
428          * caused by a signal (we can't take the break message there).
429          * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
430          */
431
432         if (oplock_message_waiting(&fds)) {
433                 DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
434                 async_processing(&fds);
435                 /*
436                  * After async processing we must go and do the select again, as
437                  * the state of the flag in fds for the server file descriptor is
438                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
439                  */
440                 goto again;
441         }
442
443         /*
444          * Are there any timed events waiting ? If so, ensure we don't
445          * select for longer than it would take to wait for them.
446          */
447
448         {
449                 struct timeval tmp;
450                 struct timeval *tp = get_timed_events_timeout(&tmp);
451
452                 if (tp) {
453                         to = timeval_min(&to, tp);
454                         if (timeval_is_zero(&to)) {
455                                 /* Process a timed event now... */
456                                 run_events();
457                         }
458                 }
459         }
460         
461         {
462                 int sav;
463                 START_PROFILE(smbd_idle);
464
465                 maxfd = select_on_fd(smbd_server_fd(), maxfd, &fds);
466                 maxfd = select_on_fd(change_notify_fd(), maxfd, &fds);
467                 maxfd = select_on_fd(oplock_notify_fd(), maxfd, &fds);
468
469                 selrtn = sys_select(maxfd+1,&fds,NULL,NULL,&to);
470                 sav = errno;
471
472                 END_PROFILE(smbd_idle);
473                 errno = sav;
474         }
475
476         /* if we get EINTR then maybe we have received an oplock
477            signal - treat this as select returning 1. This is ugly, but
478            is the best we can do until the oplock code knows more about
479            signals */
480         if (selrtn == -1 && errno == EINTR) {
481                 async_processing(&fds);
482                 /*
483                  * After async processing we must go and do the select again, as
484                  * the state of the flag in fds for the server file descriptor is
485                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
486                  */
487                 goto again;
488         }
489
490         /* Check if error */
491         if (selrtn == -1) {
492                 /* something is wrong. Maybe the socket is dead? */
493                 smb_read_error = READ_ERROR;
494                 return False;
495         } 
496     
497         /* Did we timeout ? */
498         if (selrtn == 0) {
499                 smb_read_error = READ_TIMEOUT;
500                 return False;
501         }
502
503         /*
504          * Ensure we process oplock break messages by preference.
505          * This is IMPORTANT ! Otherwise we can starve other processes
506          * sending us an oplock break message. JRA.
507          */
508
509         if (oplock_message_waiting(&fds)) {
510                 async_processing(&fds);
511                 /*
512                  * After async processing we must go and do the select again, as
513                  * the state of the flag in fds for the server file descriptor is
514                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
515                  */
516                 goto again;
517         }
518         
519         return receive_smb(smbd_server_fd(), buffer, 0);
520 }
521
522 /*
523  * Only allow 5 outstanding trans requests. We're allocating memory, so
524  * prevent a DoS.
525  */
526
527 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
528 {
529         int count = 0;
530         for (; list != NULL; list = list->next) {
531
532                 if (list->mid == mid) {
533                         return NT_STATUS_INVALID_PARAMETER;
534                 }
535
536                 count += 1;
537         }
538         if (count > 5) {
539                 return NT_STATUS_INSUFFICIENT_RESOURCES;
540         }
541
542         return NT_STATUS_OK;
543 }
544
545 /****************************************************************************
546  We're terminating and have closed all our files/connections etc.
547  If there are any pending local messages we need to respond to them
548  before termination so that other smbds don't think we just died whilst
549  holding oplocks.
550 ****************************************************************************/
551
552 void respond_to_all_remaining_local_messages(void)
553 {
554         /*
555          * Assert we have no exclusive open oplocks.
556          */
557
558         if(get_number_of_exclusive_open_oplocks()) {
559                 DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
560                         get_number_of_exclusive_open_oplocks() ));
561                 return;
562         }
563
564         process_kernel_oplocks(NULL);
565
566         return;
567 }
568
569
570 /*
571 These flags determine some of the permissions required to do an operation 
572
573 Note that I don't set NEED_WRITE on some write operations because they
574 are used by some brain-dead clients when printing, and I don't want to
575 force write permissions on print services.
576 */
577 #define AS_USER (1<<0)
578 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
579 #define TIME_INIT (1<<2)
580 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
581 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
582 #define DO_CHDIR (1<<6)
583
584 /* 
585    define a list of possible SMB messages and their corresponding
586    functions. Any message that has a NULL function is unimplemented -
587    please feel free to contribute implementations!
588 */
589 static const struct smb_message_struct {
590         const char *name;
591         int (*fn)(connection_struct *conn, char *, char *, int, int);
592         int flags;
593 } smb_messages[256] = {
594
595 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
596 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
597 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
598 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
599 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
600 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
601 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE }, 
602 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
603 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
604 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
605 /* 0x0a */ { "SMBread",reply_read,AS_USER},
606 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
607 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
608 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
609 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
610 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER}, 
611 /* 0x10 */ { "SMBchkpth",reply_chkpth,AS_USER},
612 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
613 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
614 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
615 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
616 /* 0x15 */ { NULL, NULL, 0 },
617 /* 0x16 */ { NULL, NULL, 0 },
618 /* 0x17 */ { NULL, NULL, 0 },
619 /* 0x18 */ { NULL, NULL, 0 },
620 /* 0x19 */ { NULL, NULL, 0 },
621 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
622 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
623 /* 0x1c */ { "SMBreadBs",NULL,0 },
624 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
625 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
626 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
627 /* 0x20 */ { "SMBwritec",NULL,0},
628 /* 0x21 */ { NULL, NULL, 0 },
629 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
630 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
631 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
632 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
633 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
634 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
635 /* 0x28 */ { "SMBioctls",NULL,AS_USER},
636 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
637 /* 0x2a */ { "SMBmove",NULL,AS_USER | NEED_WRITE },
638 /* 0x2b */ { "SMBecho",reply_echo,0},
639 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
640 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
641 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
642 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
643 /* 0x30 */ { NULL, NULL, 0 },
644 /* 0x31 */ { NULL, NULL, 0 },
645 /* 0x32 */ { "SMBtrans2", reply_trans2, AS_USER | CAN_IPC },
646 /* 0x33 */ { "SMBtranss2", reply_transs2, AS_USER},
647 /* 0x34 */ { "SMBfindclose", reply_findclose,AS_USER},
648 /* 0x35 */ { "SMBfindnclose", reply_findnclose, AS_USER},
649 /* 0x36 */ { NULL, NULL, 0 },
650 /* 0x37 */ { NULL, NULL, 0 },
651 /* 0x38 */ { NULL, NULL, 0 },
652 /* 0x39 */ { NULL, NULL, 0 },
653 /* 0x3a */ { NULL, NULL, 0 },
654 /* 0x3b */ { NULL, NULL, 0 },
655 /* 0x3c */ { NULL, NULL, 0 },
656 /* 0x3d */ { NULL, NULL, 0 },
657 /* 0x3e */ { NULL, NULL, 0 },
658 /* 0x3f */ { NULL, NULL, 0 },
659 /* 0x40 */ { NULL, NULL, 0 },
660 /* 0x41 */ { NULL, NULL, 0 },
661 /* 0x42 */ { NULL, NULL, 0 },
662 /* 0x43 */ { NULL, NULL, 0 },
663 /* 0x44 */ { NULL, NULL, 0 },
664 /* 0x45 */ { NULL, NULL, 0 },
665 /* 0x46 */ { NULL, NULL, 0 },
666 /* 0x47 */ { NULL, NULL, 0 },
667 /* 0x48 */ { NULL, NULL, 0 },
668 /* 0x49 */ { NULL, NULL, 0 },
669 /* 0x4a */ { NULL, NULL, 0 },
670 /* 0x4b */ { NULL, NULL, 0 },
671 /* 0x4c */ { NULL, NULL, 0 },
672 /* 0x4d */ { NULL, NULL, 0 },
673 /* 0x4e */ { NULL, NULL, 0 },
674 /* 0x4f */ { NULL, NULL, 0 },
675 /* 0x50 */ { NULL, NULL, 0 },
676 /* 0x51 */ { NULL, NULL, 0 },
677 /* 0x52 */ { NULL, NULL, 0 },
678 /* 0x53 */ { NULL, NULL, 0 },
679 /* 0x54 */ { NULL, NULL, 0 },
680 /* 0x55 */ { NULL, NULL, 0 },
681 /* 0x56 */ { NULL, NULL, 0 },
682 /* 0x57 */ { NULL, NULL, 0 },
683 /* 0x58 */ { NULL, NULL, 0 },
684 /* 0x59 */ { NULL, NULL, 0 },
685 /* 0x5a */ { NULL, NULL, 0 },
686 /* 0x5b */ { NULL, NULL, 0 },
687 /* 0x5c */ { NULL, NULL, 0 },
688 /* 0x5d */ { NULL, NULL, 0 },
689 /* 0x5e */ { NULL, NULL, 0 },
690 /* 0x5f */ { NULL, NULL, 0 },
691 /* 0x60 */ { NULL, NULL, 0 },
692 /* 0x61 */ { NULL, NULL, 0 },
693 /* 0x62 */ { NULL, NULL, 0 },
694 /* 0x63 */ { NULL, NULL, 0 },
695 /* 0x64 */ { NULL, NULL, 0 },
696 /* 0x65 */ { NULL, NULL, 0 },
697 /* 0x66 */ { NULL, NULL, 0 },
698 /* 0x67 */ { NULL, NULL, 0 },
699 /* 0x68 */ { NULL, NULL, 0 },
700 /* 0x69 */ { NULL, NULL, 0 },
701 /* 0x6a */ { NULL, NULL, 0 },
702 /* 0x6b */ { NULL, NULL, 0 },
703 /* 0x6c */ { NULL, NULL, 0 },
704 /* 0x6d */ { NULL, NULL, 0 },
705 /* 0x6e */ { NULL, NULL, 0 },
706 /* 0x6f */ { NULL, NULL, 0 },
707 /* 0x70 */ { "SMBtcon",reply_tcon,0},
708 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
709 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
710 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
711 /* 0x74 */ { "SMBulogoffX", reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
712 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
713 /* 0x76 */ { NULL, NULL, 0 },
714 /* 0x77 */ { NULL, NULL, 0 },
715 /* 0x78 */ { NULL, NULL, 0 },
716 /* 0x79 */ { NULL, NULL, 0 },
717 /* 0x7a */ { NULL, NULL, 0 },
718 /* 0x7b */ { NULL, NULL, 0 },
719 /* 0x7c */ { NULL, NULL, 0 },
720 /* 0x7d */ { NULL, NULL, 0 },
721 /* 0x7e */ { NULL, NULL, 0 },
722 /* 0x7f */ { NULL, NULL, 0 },
723 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
724 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
725 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
726 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
727 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
728 /* 0x85 */ { NULL, NULL, 0 },
729 /* 0x86 */ { NULL, NULL, 0 },
730 /* 0x87 */ { NULL, NULL, 0 },
731 /* 0x88 */ { NULL, NULL, 0 },
732 /* 0x89 */ { NULL, NULL, 0 },
733 /* 0x8a */ { NULL, NULL, 0 },
734 /* 0x8b */ { NULL, NULL, 0 },
735 /* 0x8c */ { NULL, NULL, 0 },
736 /* 0x8d */ { NULL, NULL, 0 },
737 /* 0x8e */ { NULL, NULL, 0 },
738 /* 0x8f */ { NULL, NULL, 0 },
739 /* 0x90 */ { NULL, NULL, 0 },
740 /* 0x91 */ { NULL, NULL, 0 },
741 /* 0x92 */ { NULL, NULL, 0 },
742 /* 0x93 */ { NULL, NULL, 0 },
743 /* 0x94 */ { NULL, NULL, 0 },
744 /* 0x95 */ { NULL, NULL, 0 },
745 /* 0x96 */ { NULL, NULL, 0 },
746 /* 0x97 */ { NULL, NULL, 0 },
747 /* 0x98 */ { NULL, NULL, 0 },
748 /* 0x99 */ { NULL, NULL, 0 },
749 /* 0x9a */ { NULL, NULL, 0 },
750 /* 0x9b */ { NULL, NULL, 0 },
751 /* 0x9c */ { NULL, NULL, 0 },
752 /* 0x9d */ { NULL, NULL, 0 },
753 /* 0x9e */ { NULL, NULL, 0 },
754 /* 0x9f */ { NULL, NULL, 0 },
755 /* 0xa0 */ { "SMBnttrans", reply_nttrans, AS_USER | CAN_IPC },
756 /* 0xa1 */ { "SMBnttranss", reply_nttranss, AS_USER | CAN_IPC },
757 /* 0xa2 */ { "SMBntcreateX", reply_ntcreate_and_X, AS_USER | CAN_IPC },
758 /* 0xa3 */ { NULL, NULL, 0 },
759 /* 0xa4 */ { "SMBntcancel", reply_ntcancel, 0 },
760 /* 0xa5 */ { "SMBntrename", reply_ntrename, AS_USER | NEED_WRITE },
761 /* 0xa6 */ { NULL, NULL, 0 },
762 /* 0xa7 */ { NULL, NULL, 0 },
763 /* 0xa8 */ { NULL, NULL, 0 },
764 /* 0xa9 */ { NULL, NULL, 0 },
765 /* 0xaa */ { NULL, NULL, 0 },
766 /* 0xab */ { NULL, NULL, 0 },
767 /* 0xac */ { NULL, NULL, 0 },
768 /* 0xad */ { NULL, NULL, 0 },
769 /* 0xae */ { NULL, NULL, 0 },
770 /* 0xaf */ { NULL, NULL, 0 },
771 /* 0xb0 */ { NULL, NULL, 0 },
772 /* 0xb1 */ { NULL, NULL, 0 },
773 /* 0xb2 */ { NULL, NULL, 0 },
774 /* 0xb3 */ { NULL, NULL, 0 },
775 /* 0xb4 */ { NULL, NULL, 0 },
776 /* 0xb5 */ { NULL, NULL, 0 },
777 /* 0xb6 */ { NULL, NULL, 0 },
778 /* 0xb7 */ { NULL, NULL, 0 },
779 /* 0xb8 */ { NULL, NULL, 0 },
780 /* 0xb9 */ { NULL, NULL, 0 },
781 /* 0xba */ { NULL, NULL, 0 },
782 /* 0xbb */ { NULL, NULL, 0 },
783 /* 0xbc */ { NULL, NULL, 0 },
784 /* 0xbd */ { NULL, NULL, 0 },
785 /* 0xbe */ { NULL, NULL, 0 },
786 /* 0xbf */ { NULL, NULL, 0 },
787 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
788 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
789 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
790 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
791 /* 0xc4 */ { NULL, NULL, 0 },
792 /* 0xc5 */ { NULL, NULL, 0 },
793 /* 0xc6 */ { NULL, NULL, 0 },
794 /* 0xc7 */ { NULL, NULL, 0 },
795 /* 0xc8 */ { NULL, NULL, 0 },
796 /* 0xc9 */ { NULL, NULL, 0 },
797 /* 0xca */ { NULL, NULL, 0 },
798 /* 0xcb */ { NULL, NULL, 0 },
799 /* 0xcc */ { NULL, NULL, 0 },
800 /* 0xcd */ { NULL, NULL, 0 },
801 /* 0xce */ { NULL, NULL, 0 },
802 /* 0xcf */ { NULL, NULL, 0 },
803 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
804 /* 0xd1 */ { "SMBsendb",NULL,AS_GUEST},
805 /* 0xd2 */ { "SMBfwdname",NULL,AS_GUEST},
806 /* 0xd3 */ { "SMBcancelf",NULL,AS_GUEST},
807 /* 0xd4 */ { "SMBgetmac",NULL,AS_GUEST},
808 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
809 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
810 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
811 /* 0xd8 */ { NULL, NULL, 0 },
812 /* 0xd9 */ { NULL, NULL, 0 },
813 /* 0xda */ { NULL, NULL, 0 },
814 /* 0xdb */ { NULL, NULL, 0 },
815 /* 0xdc */ { NULL, NULL, 0 },
816 /* 0xdd */ { NULL, NULL, 0 },
817 /* 0xde */ { NULL, NULL, 0 },
818 /* 0xdf */ { NULL, NULL, 0 },
819 /* 0xe0 */ { NULL, NULL, 0 },
820 /* 0xe1 */ { NULL, NULL, 0 },
821 /* 0xe2 */ { NULL, NULL, 0 },
822 /* 0xe3 */ { NULL, NULL, 0 },
823 /* 0xe4 */ { NULL, NULL, 0 },
824 /* 0xe5 */ { NULL, NULL, 0 },
825 /* 0xe6 */ { NULL, NULL, 0 },
826 /* 0xe7 */ { NULL, NULL, 0 },
827 /* 0xe8 */ { NULL, NULL, 0 },
828 /* 0xe9 */ { NULL, NULL, 0 },
829 /* 0xea */ { NULL, NULL, 0 },
830 /* 0xeb */ { NULL, NULL, 0 },
831 /* 0xec */ { NULL, NULL, 0 },
832 /* 0xed */ { NULL, NULL, 0 },
833 /* 0xee */ { NULL, NULL, 0 },
834 /* 0xef */ { NULL, NULL, 0 },
835 /* 0xf0 */ { NULL, NULL, 0 },
836 /* 0xf1 */ { NULL, NULL, 0 },
837 /* 0xf2 */ { NULL, NULL, 0 },
838 /* 0xf3 */ { NULL, NULL, 0 },
839 /* 0xf4 */ { NULL, NULL, 0 },
840 /* 0xf5 */ { NULL, NULL, 0 },
841 /* 0xf6 */ { NULL, NULL, 0 },
842 /* 0xf7 */ { NULL, NULL, 0 },
843 /* 0xf8 */ { NULL, NULL, 0 },
844 /* 0xf9 */ { NULL, NULL, 0 },
845 /* 0xfa */ { NULL, NULL, 0 },
846 /* 0xfb */ { NULL, NULL, 0 },
847 /* 0xfc */ { NULL, NULL, 0 },
848 /* 0xfd */ { NULL, NULL, 0 },
849 /* 0xfe */ { NULL, NULL, 0 },
850 /* 0xff */ { NULL, NULL, 0 }
851
852 };
853
854 /*******************************************************************
855  Dump a packet to a file.
856 ********************************************************************/
857
858 static void smb_dump(const char *name, int type, char *data, ssize_t len)
859 {
860         int fd, i;
861         pstring fname;
862         if (DEBUGLEVEL < 50) return;
863
864         if (len < 4) len = smb_len(data)+4;
865         for (i=1;i<100;i++) {
866                 slprintf(fname,sizeof(fname)-1, "/tmp/%s.%d.%s", name, i,
867                                 type ? "req" : "resp");
868                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
869                 if (fd != -1 || errno != EEXIST) break;
870         }
871         if (fd != -1) {
872                 ssize_t ret = write(fd, data, len);
873                 if (ret != len)
874                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
875                 close(fd);
876                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
877         }
878 }
879
880
881 /****************************************************************************
882  Do a switch on the message type, and return the response size
883 ****************************************************************************/
884
885 static int switch_message(int type,char *inbuf,char *outbuf,int size,int bufsize)
886 {
887         static pid_t pid= (pid_t)-1;
888         int outsize = 0;
889
890         type &= 0xff;
891
892         if (pid == (pid_t)-1)
893                 pid = sys_getpid();
894
895         errno = 0;
896
897         last_message = type;
898
899         /* Make sure this is an SMB packet. smb_size contains NetBIOS header so subtract 4 from it. */
900         if ((strncmp(smb_base(inbuf),"\377SMB",4) != 0) || (size < (smb_size - 4))) {
901                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",smb_len(inbuf)));
902                 exit_server_cleanly("Non-SMB packet");
903                 return(-1);
904         }
905
906         /* yuck! this is an interim measure before we get rid of our
907                 current inbuf/outbuf system */
908         global_smbpid = SVAL(inbuf,smb_pid);
909
910         if (smb_messages[type].fn == NULL) {
911                 DEBUG(0,("Unknown message type %d!\n",type));
912                 smb_dump("Unknown", 1, inbuf, size);
913                 outsize = reply_unknown(inbuf,outbuf);
914         } else {
915                 int flags = smb_messages[type].flags;
916                 static uint16 last_session_tag = UID_FIELD_INVALID;
917                 /* In share mode security we must ignore the vuid. */
918                 uint16 session_tag = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID : SVAL(inbuf,smb_uid);
919                 connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
920
921                 DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n",smb_fn_name(type),(int)pid,(unsigned long)conn));
922
923                 smb_dump(smb_fn_name(type), 1, inbuf, size);
924
925                 /* Ensure this value is replaced in the incoming packet. */
926                 SSVAL(inbuf,smb_uid,session_tag);
927
928                 /*
929                  * Ensure the correct username is in current_user_info.
930                  * This is a really ugly bugfix for problems with
931                  * multiple session_setup_and_X's being done and
932                  * allowing %U and %G substitutions to work correctly.
933                  * There is a reason this code is done here, don't
934                  * move it unless you know what you're doing... :-).
935                  * JRA.
936                  */
937
938                 if (session_tag != last_session_tag) {
939                         user_struct *vuser = NULL;
940
941                         last_session_tag = session_tag;
942                         if(session_tag != UID_FIELD_INVALID) {
943                                 vuser = get_valid_user_struct(session_tag);           
944                                 if (vuser) {
945                                         set_current_user_info(&vuser->user);
946                                 }
947                         }
948                 }
949
950                 /* Does this call need to be run as the connected user? */
951                 if (flags & AS_USER) {
952
953                         /* Does this call need a valid tree connection? */
954                         if (!conn) {
955                                 /* Amazingly, the error code depends on the command (from Samba4). */
956                                 if (type == SMBntcreateX) {
957                                         return ERROR_NT(NT_STATUS_INVALID_HANDLE);
958                                 } else {
959                                         return ERROR_DOS(ERRSRV, ERRinvnid);
960                                 }
961                         }
962
963                         if (!change_to_user(conn,session_tag)) {
964                                 return(ERROR_NT(NT_STATUS_DOS(ERRSRV,ERRbaduid)));
965                         }
966
967                         /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
968
969                         /* Does it need write permission? */
970                         if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
971                                 return(ERROR_DOS(ERRSRV,ERRaccess));
972                         }
973
974                         /* IPC services are limited */
975                         if (IS_IPC(conn) && !(flags & CAN_IPC)) {
976                                 return(ERROR_DOS(ERRSRV,ERRaccess));
977                         }
978                 } else {
979                         /* This call needs to be run as root */
980                         change_to_root_user();
981                 }
982
983                 /* load service specific parameters */
984                 if (conn) {
985                         if (!set_current_service(conn,SVAL(inbuf,smb_flg),(flags & (AS_USER|DO_CHDIR)?True:False))) {
986                                 return(ERROR_DOS(ERRSRV,ERRaccess));
987                         }
988                         conn->num_smb_operations++;
989                 }
990
991                 /* does this protocol need to be run as guest? */
992                 if ((flags & AS_GUEST) && (!change_to_guest() || 
993                                 !check_access(smbd_server_fd(), lp_hostsallow(-1), lp_hostsdeny(-1)))) {
994                         return(ERROR_DOS(ERRSRV,ERRaccess));
995                 }
996
997                 current_inbuf = inbuf; /* In case we need to defer this message in open... */
998                 outsize = smb_messages[type].fn(conn, inbuf,outbuf,size,bufsize);
999         }
1000
1001         smb_dump(smb_fn_name(type), 0, outbuf, outsize);
1002
1003         return(outsize);
1004 }
1005
1006 /****************************************************************************
1007  Construct a reply to the incoming packet.
1008 ****************************************************************************/
1009
1010 static int construct_reply(char *inbuf,char *outbuf,int size,int bufsize)
1011 {
1012         int type = CVAL(inbuf,smb_com);
1013         int outsize = 0;
1014         int msg_type = CVAL(inbuf,0);
1015
1016         chain_size = 0;
1017         file_chain_reset();
1018         reset_chain_p();
1019
1020         if (msg_type != 0)
1021                 return(reply_special(inbuf,outbuf));  
1022
1023         construct_reply_common(inbuf, outbuf);
1024
1025         outsize = switch_message(type,inbuf,outbuf,size,bufsize);
1026
1027         outsize += chain_size;
1028
1029         if(outsize > 4)
1030                 smb_setlen(outbuf,outsize - 4);
1031         return(outsize);
1032 }
1033
1034 /****************************************************************************
1035  Process an smb from the client
1036 ****************************************************************************/
1037
1038 static void process_smb(char *inbuf, char *outbuf)
1039 {
1040         static int trans_num;
1041         int msg_type = CVAL(inbuf,0);
1042         int32 len = smb_len(inbuf);
1043         int nread = len + 4;
1044
1045         DO_PROFILE_INC(smb_count);
1046
1047         if (trans_num == 0) {
1048                 /* on the first packet, check the global hosts allow/ hosts
1049                 deny parameters before doing any parsing of the packet
1050                 passed to us by the client.  This prevents attacks on our
1051                 parsing code from hosts not in the hosts allow list */
1052                 if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
1053                                   lp_hostsdeny(-1))) {
1054                         /* send a negative session response "not listening on calling name" */
1055                         static unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
1056                         DEBUG( 1, ( "Connection denied from %s\n", client_addr() ) );
1057                         (void)send_smb(smbd_server_fd(),(char *)buf);
1058                         exit_server_cleanly("connection denied");
1059                 }
1060         }
1061
1062         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type, len ) );
1063         DEBUG( 3, ( "Transaction %d of length %d\n", trans_num, nread ) );
1064
1065         if (msg_type == 0)
1066                 show_msg(inbuf);
1067         else if(msg_type == SMBkeepalive)
1068                 return; /* Keepalive packet. */
1069
1070         nread = construct_reply(inbuf,outbuf,nread,max_send);
1071       
1072         if(nread > 0) {
1073                 if (CVAL(outbuf,0) == 0)
1074                         show_msg(outbuf);
1075         
1076                 if (nread != smb_len(outbuf) + 4) {
1077                         DEBUG(0,("ERROR: Invalid message response size! %d %d\n",
1078                                 nread, smb_len(outbuf)));
1079                 } else if (!send_smb(smbd_server_fd(),outbuf)) {
1080                         exit_server_cleanly("process_smb: send_smb failed.");
1081                 }
1082         }
1083         trans_num++;
1084 }
1085
1086 /****************************************************************************
1087  Return a string containing the function name of a SMB command.
1088 ****************************************************************************/
1089
1090 const char *smb_fn_name(int type)
1091 {
1092         const char *unknown_name = "SMBunknown";
1093
1094         if (smb_messages[type].name == NULL)
1095                 return(unknown_name);
1096
1097         return(smb_messages[type].name);
1098 }
1099
1100 /****************************************************************************
1101  Helper functions for contruct_reply.
1102 ****************************************************************************/
1103
1104 static uint32 common_flags2 = FLAGS2_LONG_PATH_COMPONENTS|FLAGS2_32_BIT_ERROR_CODES;
1105
1106 void add_to_common_flags2(uint32 v)
1107 {
1108         common_flags2 |= v;
1109 }
1110
1111 void remove_from_common_flags2(uint32 v)
1112 {
1113         common_flags2 &= ~v;
1114 }
1115
1116 void construct_reply_common(char *inbuf,char *outbuf)
1117 {
1118         set_message(outbuf,0,0,False);
1119         
1120         SCVAL(outbuf,smb_com,CVAL(inbuf,smb_com));
1121         SIVAL(outbuf,smb_rcls,0);
1122         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES)); 
1123         SSVAL(outbuf,smb_flg2,
1124                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1125                 common_flags2);
1126         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1127
1128         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1129         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1130         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1131         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1132 }
1133
1134 /****************************************************************************
1135  Construct a chained reply and add it to the already made reply
1136 ****************************************************************************/
1137
1138 int chain_reply(char *inbuf,char *outbuf,int size,int bufsize)
1139 {
1140         static char *orig_inbuf;
1141         static char *orig_outbuf;
1142         int smb_com1, smb_com2 = CVAL(inbuf,smb_vwv0);
1143         unsigned smb_off2 = SVAL(inbuf,smb_vwv1);
1144         char *inbuf2, *outbuf2;
1145         int outsize2;
1146         char inbuf_saved[smb_wct];
1147         char outbuf_saved[smb_wct];
1148         int outsize = smb_len(outbuf) + 4;
1149
1150         /* maybe its not chained */
1151         if (smb_com2 == 0xFF) {
1152                 SCVAL(outbuf,smb_vwv0,0xFF);
1153                 return outsize;
1154         }
1155
1156         if (chain_size == 0) {
1157                 /* this is the first part of the chain */
1158                 orig_inbuf = inbuf;
1159                 orig_outbuf = outbuf;
1160         }
1161
1162         /*
1163          * The original Win95 redirector dies on a reply to
1164          * a lockingX and read chain unless the chain reply is
1165          * 4 byte aligned. JRA.
1166          */
1167
1168         outsize = (outsize + 3) & ~3;
1169
1170         /* we need to tell the client where the next part of the reply will be */
1171         SSVAL(outbuf,smb_vwv1,smb_offset(outbuf+outsize,outbuf));
1172         SCVAL(outbuf,smb_vwv0,smb_com2);
1173
1174         /* remember how much the caller added to the chain, only counting stuff
1175                 after the parameter words */
1176         chain_size += outsize - smb_wct;
1177
1178         /* work out pointers into the original packets. The
1179                 headers on these need to be filled in */
1180         inbuf2 = orig_inbuf + smb_off2 + 4 - smb_wct;
1181         outbuf2 = orig_outbuf + SVAL(outbuf,smb_vwv1) + 4 - smb_wct;
1182
1183         /* remember the original command type */
1184         smb_com1 = CVAL(orig_inbuf,smb_com);
1185
1186         /* save the data which will be overwritten by the new headers */
1187         memcpy(inbuf_saved,inbuf2,smb_wct);
1188         memcpy(outbuf_saved,outbuf2,smb_wct);
1189
1190         /* give the new packet the same header as the last part of the SMB */
1191         memmove(inbuf2,inbuf,smb_wct);
1192
1193         /* create the in buffer */
1194         SCVAL(inbuf2,smb_com,smb_com2);
1195
1196         /* create the out buffer */
1197         construct_reply_common(inbuf2, outbuf2);
1198
1199         DEBUG(3,("Chained message\n"));
1200         show_msg(inbuf2);
1201
1202         /* process the request */
1203         outsize2 = switch_message(smb_com2,inbuf2,outbuf2,size-chain_size,
1204                                 bufsize-chain_size);
1205
1206         /* copy the new reply and request headers over the old ones, but
1207                 preserve the smb_com field */
1208         memmove(orig_outbuf,outbuf2,smb_wct);
1209         SCVAL(orig_outbuf,smb_com,smb_com1);
1210
1211         /* restore the saved data, being careful not to overwrite any
1212                 data from the reply header */
1213         memcpy(inbuf2,inbuf_saved,smb_wct);
1214
1215         {
1216                 int ofs = smb_wct - PTR_DIFF(outbuf2,orig_outbuf);
1217                 if (ofs < 0) ofs = 0;
1218                         memmove(outbuf2+ofs,outbuf_saved+ofs,smb_wct-ofs);
1219         }
1220
1221         return outsize2;
1222 }
1223
1224 /****************************************************************************
1225  Setup the needed select timeout in milliseconds.
1226 ****************************************************************************/
1227
1228 static int setup_select_timeout(void)
1229 {
1230         int select_timeout;
1231         int t;
1232
1233         select_timeout = blocking_locks_timeout_ms(SMBD_SELECT_TIMEOUT*1000);
1234
1235         t = change_notify_timeout();
1236         DEBUG(10, ("change_notify_timeout: %d\n", t));
1237         if (t != -1) {
1238                 select_timeout = MIN(select_timeout, t*1000);
1239         }
1240
1241         if (print_notify_messages_pending()) {
1242                 select_timeout = MIN(select_timeout, 1000);
1243         }
1244
1245         return select_timeout;
1246 }
1247
1248 /****************************************************************************
1249  Check if services need reloading.
1250 ****************************************************************************/
1251
1252 void check_reload(time_t t)
1253 {
1254         static pid_t mypid = 0;
1255         static time_t last_smb_conf_reload_time = 0;
1256         static time_t last_printer_reload_time = 0;
1257         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1258
1259         if(last_smb_conf_reload_time == 0) {
1260                 last_smb_conf_reload_time = t;
1261                 /* Our printing subsystem might not be ready at smbd start up.
1262                    Then no printer is available till the first printers check
1263                    is performed.  A lower initial interval circumvents this. */
1264                 if ( printcap_cache_time > 60 )
1265                         last_printer_reload_time = t - printcap_cache_time + 60;
1266                 else
1267                         last_printer_reload_time = t;
1268         }
1269
1270         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1271                 /* randomize over 60 second the printcap reload to avoid all
1272                  * process hitting cupsd at the same time */
1273                 int time_range = 60;
1274
1275                 last_printer_reload_time += random() % time_range;
1276                 mypid = getpid();
1277         }
1278
1279         if (reload_after_sighup || (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK)) {
1280                 reload_services(True);
1281                 reload_after_sighup = False;
1282                 last_smb_conf_reload_time = t;
1283         }
1284
1285         /* 'printcap cache time = 0' disable the feature */
1286         
1287         if ( printcap_cache_time != 0 )
1288         { 
1289                 /* see if it's time to reload or if the clock has been set back */
1290                 
1291                 if ( (t >= last_printer_reload_time+printcap_cache_time) 
1292                         || (t-last_printer_reload_time  < 0) ) 
1293                 {
1294                         DEBUG( 3,( "Printcap cache time expired.\n"));
1295                         reload_printers();
1296                         last_printer_reload_time = t;
1297                 }
1298         }
1299 }
1300
1301 /****************************************************************************
1302  Process any timeout housekeeping. Return False if the caller should exit.
1303 ****************************************************************************/
1304
1305 static BOOL timeout_processing(int deadtime, int *select_timeout, time_t *last_timeout_processing_time)
1306 {
1307         static time_t last_keepalive_sent_time = 0;
1308         static time_t last_idle_closed_check = 0;
1309         time_t t;
1310         BOOL allidle = True;
1311
1312         if (smb_read_error == READ_EOF) {
1313                 DEBUG(3,("timeout_processing: End of file from client (client has disconnected).\n"));
1314                 return False;
1315         }
1316
1317         if (smb_read_error == READ_ERROR) {
1318                 DEBUG(3,("timeout_processing: receive_smb error (%s) Exiting\n",
1319                         strerror(errno)));
1320                 return False;
1321         }
1322
1323         if (smb_read_error == READ_BAD_SIG) {
1324                 DEBUG(3,("timeout_processing: receive_smb error bad smb signature. Exiting\n"));
1325                 return False;
1326         }
1327
1328         *last_timeout_processing_time = t = time(NULL);
1329
1330         if(last_keepalive_sent_time == 0)
1331                 last_keepalive_sent_time = t;
1332
1333         if(last_idle_closed_check == 0)
1334                 last_idle_closed_check = t;
1335
1336         /* become root again if waiting */
1337         change_to_root_user();
1338
1339         /* run all registered idle events */
1340         smb_run_idle_events(t);
1341
1342         /* check if we need to reload services */
1343         check_reload(t);
1344
1345         /* automatic timeout if all connections are closed */      
1346         if (conn_num_open()==0 && (t - last_idle_closed_check) >= IDLE_CLOSED_TIMEOUT) {
1347                 DEBUG( 2, ( "Closing idle connection\n" ) );
1348                 return False;
1349         } else {
1350                 last_idle_closed_check = t;
1351         }
1352
1353         if (keepalive && (t - last_keepalive_sent_time)>keepalive) {
1354                 if (!send_keepalive(smbd_server_fd())) {
1355                         DEBUG( 2, ( "Keepalive failed - exiting.\n" ) );
1356                         return False;
1357                 }
1358
1359                 /* send a keepalive for a password server or the like.
1360                         This is attached to the auth_info created in the
1361                 negprot */
1362                 if (negprot_global_auth_context && negprot_global_auth_context->challenge_set_method 
1363                                 && negprot_global_auth_context->challenge_set_method->send_keepalive) {
1364
1365                         negprot_global_auth_context->challenge_set_method->send_keepalive
1366                         (&negprot_global_auth_context->challenge_set_method->private_data);
1367                 }
1368
1369                 last_keepalive_sent_time = t;
1370         }
1371
1372         /* check for connection timeouts */
1373         allidle = conn_idle_all(t, deadtime);
1374
1375         if (allidle && conn_num_open()>0) {
1376                 DEBUG(2,("Closing idle connection 2.\n"));
1377                 return False;
1378         }
1379
1380         if(global_machine_password_needs_changing && 
1381                         /* for ADS we need to do a regular ADS password change, not a domain
1382                                         password change */
1383                         lp_security() == SEC_DOMAIN) {
1384
1385                 unsigned char trust_passwd_hash[16];
1386                 time_t lct;
1387
1388                 /*
1389                  * We're in domain level security, and the code that
1390                  * read the machine password flagged that the machine
1391                  * password needs changing.
1392                  */
1393
1394                 /*
1395                  * First, open the machine password file with an exclusive lock.
1396                  */
1397
1398                 if (secrets_lock_trust_account_password(lp_workgroup(), True) == False) {
1399                         DEBUG(0,("process: unable to lock the machine account password for \
1400 machine %s in domain %s.\n", global_myname(), lp_workgroup() ));
1401                         return True;
1402                 }
1403
1404                 if(!secrets_fetch_trust_account_password(lp_workgroup(), trust_passwd_hash, &lct, NULL)) {
1405                         DEBUG(0,("process: unable to read the machine account password for \
1406 machine %s in domain %s.\n", global_myname(), lp_workgroup()));
1407                         secrets_lock_trust_account_password(lp_workgroup(), False);
1408                         return True;
1409                 }
1410
1411                 /*
1412                  * Make sure someone else hasn't already done this.
1413                  */
1414
1415                 if(t < lct + lp_machine_password_timeout()) {
1416                         global_machine_password_needs_changing = False;
1417                         secrets_lock_trust_account_password(lp_workgroup(), False);
1418                         return True;
1419                 }
1420
1421                 /* always just contact the PDC here */
1422     
1423                 change_trust_account_password( lp_workgroup(), NULL);
1424                 global_machine_password_needs_changing = False;
1425                 secrets_lock_trust_account_password(lp_workgroup(), False);
1426         }
1427
1428         /*
1429          * Check to see if we have any blocking locks
1430          * outstanding on the queue.
1431          */
1432         process_blocking_lock_queue();
1433
1434         /* update printer queue caches if necessary */
1435   
1436         update_monitored_printq_cache();
1437   
1438         /*
1439          * Check to see if we have any change notifies 
1440          * outstanding on the queue.
1441          */
1442         process_pending_change_notify_queue(t);
1443
1444         /*
1445          * Now we are root, check if the log files need pruning.
1446          * Force a log file check.
1447          */
1448         force_check_log_size();
1449         check_log_size();
1450
1451         /* Send any queued printer notify message to interested smbd's. */
1452
1453         print_notify_send_messages(0);
1454
1455         /*
1456          * Modify the select timeout depending upon
1457          * what we have remaining in our queues.
1458          */
1459
1460         *select_timeout = setup_select_timeout();
1461
1462         return True;
1463 }
1464
1465 /****************************************************************************
1466  Accessor functions for InBuffer, OutBuffer.
1467 ****************************************************************************/
1468
1469 char *get_InBuffer(void)
1470 {
1471         return InBuffer;
1472 }
1473
1474 void set_InBuffer(char *new_inbuf)
1475 {
1476         InBuffer = new_inbuf;
1477         current_inbuf = InBuffer;
1478 }
1479
1480 char *get_OutBuffer(void)
1481 {
1482         return OutBuffer;
1483 }
1484
1485 void set_OutBuffer(char *new_outbuf)
1486 {
1487         OutBuffer = new_outbuf;
1488 }
1489
1490 /****************************************************************************
1491  Free an InBuffer. Checks if not in use by aio system.
1492  Must have been allocated by NewInBuffer.
1493 ****************************************************************************/
1494
1495 void free_InBuffer(char *inbuf)
1496 {
1497         if (!aio_inbuffer_in_use(inbuf)) {
1498                 if (current_inbuf == inbuf) {
1499                         current_inbuf = NULL;
1500                 }
1501                 SAFE_FREE(inbuf);
1502         }
1503 }
1504
1505 /****************************************************************************
1506  Free an OutBuffer. No outbuffers currently stolen by aio system.
1507  Must have been allocated by NewInBuffer.
1508 ****************************************************************************/
1509
1510 void free_OutBuffer(char *outbuf)
1511 {
1512         SAFE_FREE(outbuf);
1513 }
1514
1515 const int total_buffer_size = (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE + SAFETY_MARGIN);
1516
1517 /****************************************************************************
1518  Allocate a new InBuffer. Returns the new and old ones.
1519 ****************************************************************************/
1520
1521 char *NewInBuffer(char **old_inbuf)
1522 {
1523         char *new_inbuf = (char *)SMB_MALLOC(total_buffer_size);
1524         if (!new_inbuf) {
1525                 return NULL;
1526         }
1527         if (old_inbuf) {
1528                 *old_inbuf = InBuffer;
1529         }
1530         InBuffer = new_inbuf;
1531 #if defined(DEVELOPER)
1532         clobber_region(SAFE_STRING_FUNCTION_NAME, SAFE_STRING_LINE, InBuffer, total_buffer_size);
1533 #endif
1534         return InBuffer;
1535 }
1536
1537 /****************************************************************************
1538  Allocate a new OutBuffer. Returns the new and old ones.
1539 ****************************************************************************/
1540
1541 char *NewOutBuffer(char **old_outbuf)
1542 {
1543         char *new_outbuf = (char *)SMB_MALLOC(total_buffer_size);
1544         if (!new_outbuf) {
1545                 return NULL;
1546         }
1547         if (old_outbuf) {
1548                 *old_outbuf = OutBuffer;
1549         }
1550         OutBuffer = new_outbuf;
1551 #if defined(DEVELOPER)
1552         clobber_region(SAFE_STRING_FUNCTION_NAME, SAFE_STRING_LINE, OutBuffer, total_buffer_size);
1553 #endif
1554         return OutBuffer;
1555 }
1556
1557 /****************************************************************************
1558  Process commands from the client
1559 ****************************************************************************/
1560
1561 void smbd_process(void)
1562 {
1563         time_t last_timeout_processing_time = time(NULL);
1564         unsigned int num_smbs = 0;
1565
1566         /* Allocate the primary Inbut/Output buffers. */
1567
1568         if ((NewInBuffer(NULL) == NULL) || (NewOutBuffer(NULL) == NULL)) 
1569                 return;
1570
1571         max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
1572
1573         while (True) {
1574                 int deadtime = lp_deadtime()*60;
1575                 int select_timeout = setup_select_timeout();
1576                 int num_echos;
1577
1578                 if (deadtime <= 0)
1579                         deadtime = DEFAULT_SMBD_TIMEOUT;
1580
1581                 errno = 0;      
1582                 
1583                 /* free up temporary memory */
1584                 lp_TALLOC_FREE();
1585                 main_loop_TALLOC_FREE();
1586
1587                 /* Did someone ask for immediate checks on things like blocking locks ? */
1588                 if (select_timeout == 0) {
1589                         if(!timeout_processing( deadtime, &select_timeout, &last_timeout_processing_time))
1590                                 return;
1591                         num_smbs = 0; /* Reset smb counter. */
1592                 }
1593
1594                 run_events();
1595
1596 #if defined(DEVELOPER)
1597                 clobber_region(SAFE_STRING_FUNCTION_NAME, SAFE_STRING_LINE, InBuffer, total_buffer_size);
1598 #endif
1599
1600                 while (!receive_message_or_smb(InBuffer,BUFFER_SIZE+LARGE_WRITEX_HDR_SIZE,select_timeout)) {
1601                         if(!timeout_processing( deadtime, &select_timeout, &last_timeout_processing_time))
1602                                 return;
1603                         num_smbs = 0; /* Reset smb counter. */
1604                 }
1605
1606                 /*
1607                  * Ensure we do timeout processing if the SMB we just got was
1608                  * only an echo request. This allows us to set the select
1609                  * timeout in 'receive_message_or_smb()' to any value we like
1610                  * without worrying that the client will send echo requests
1611                  * faster than the select timeout, thus starving out the
1612                  * essential processing (change notify, blocking locks) that
1613                  * the timeout code does. JRA.
1614                  */ 
1615                 num_echos = smb_echo_count;
1616
1617                 clobber_region(SAFE_STRING_FUNCTION_NAME, SAFE_STRING_LINE, OutBuffer, total_buffer_size);
1618
1619                 process_smb(InBuffer, OutBuffer);
1620
1621                 if (smb_echo_count != num_echos) {
1622                         if(!timeout_processing( deadtime, &select_timeout, &last_timeout_processing_time))
1623                                 return;
1624                         num_smbs = 0; /* Reset smb counter. */
1625                 }
1626
1627                 num_smbs++;
1628
1629                 /*
1630                  * If we are getting smb requests in a constant stream
1631                  * with no echos, make sure we attempt timeout processing
1632                  * every select_timeout milliseconds - but only check for this
1633                  * every 200 smb requests.
1634                  */
1635                 
1636                 if ((num_smbs % 200) == 0) {
1637                         time_t new_check_time = time(NULL);
1638                         if(new_check_time - last_timeout_processing_time >= (select_timeout/1000)) {
1639                                 if(!timeout_processing( deadtime, &select_timeout, &last_timeout_processing_time))
1640                                         return;
1641                                 num_smbs = 0; /* Reset smb counter. */
1642                                 last_timeout_processing_time = new_check_time; /* Reset time. */
1643                         }
1644                 }
1645
1646                 /* The timeout_processing function isn't run nearly
1647                    often enough to implement 'max log size' without
1648                    overrunning the size of the file by many megabytes.
1649                    This is especially true if we are running at debug
1650                    level 10.  Checking every 50 SMBs is a nice
1651                    tradeoff of performance vs log file size overrun. */
1652
1653                 if ((num_smbs % 50) == 0 && need_to_check_log_size()) {
1654                         change_to_root_user();
1655                         check_log_size();
1656                 }
1657         }
1658 }