Asterisk - The Open Source Telephony Project  18.5.0
udptl.c
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1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * UDPTL support for T.38
5  *
6  * Copyright (C) 2005, Steve Underwood, partly based on RTP code which is
7  * Copyright (C) 1999-2009, Digium, Inc.
8  *
9  * Steve Underwood <[email protected]>
10  * Kevin P. Fleming <[email protected]>
11  *
12  * See http://www.asterisk.org for more information about
13  * the Asterisk project. Please do not directly contact
14  * any of the maintainers of this project for assistance;
15  * the project provides a web site, mailing lists and IRC
16  * channels for your use.
17  *
18  * This program is free software, distributed under the terms of
19  * the GNU General Public License Version 2. See the LICENSE file
20  * at the top of the source tree.
21  *
22  * A license has been granted to Digium (via disclaimer) for the use of
23  * this code.
24  */
25 
26 /*!
27  * \file
28  *
29  * \brief UDPTL support for T.38 faxing
30  *
31  *
32  * \author Mark Spencer <[email protected]>
33  * \author Steve Underwood <[email protected]>
34  * \author Kevin P. Fleming <[email protected]>
35  *
36  * \page T38fax_udptl T.38 support :: UDPTL
37  *
38  * Asterisk supports T.38 fax passthrough, origination and termination. It does
39  * not support gateway operation. The only channel driver that supports T.38 at
40  * this time is chan_sip.
41  *
42  * UDPTL is handled very much like RTP. It can be reinvited to go directly between
43  * the endpoints, without involving Asterisk in the media stream.
44  *
45  * \b References:
46  * - chan_sip.c
47  * - udptl.c
48  * - app_fax.c
49  */
50 
51 /*! \li \ref udptl.c uses the configuration file \ref udptl.conf
52  * \addtogroup configuration_file Configuration Files
53  */
54 
55 /*!
56  * \page udptl.conf udptl.conf
57  * \verbinclude udptl.conf.sample
58  */
59 
60 /*** MODULEINFO
61  <support_level>core</support_level>
62  ***/
63 
64 #include "asterisk.h"
65 
66 #include <sys/time.h>
67 #include <signal.h>
68 #include <fcntl.h>
69 
70 #include "asterisk/module.h"
71 #include "asterisk/udptl.h"
72 #include "asterisk/frame.h"
73 #include "asterisk/channel.h"
74 #include "asterisk/acl.h"
76 #include "asterisk/lock.h"
77 #include "asterisk/utils.h"
78 #include "asterisk/netsock2.h"
79 #include "asterisk/cli.h"
80 #include "asterisk/unaligned.h"
81 
82 /*** DOCUMENTATION
83  <configInfo name="udptl" language="en_US">
84  <configFile name="udptl.conf">
85  <configObject name="global">
86  <synopsis>Global options for configuring UDPTL</synopsis>
87  <configOption name="udptlstart">
88  <synopsis>The start of the UDPTL port range</synopsis>
89  </configOption>
90  <configOption name="udptlend">
91  <synopsis>The end of the UDPTL port range</synopsis>
92  </configOption>
93  <configOption name="udptlchecksums">
94  <synopsis>Whether to enable or disable UDP checksums on UDPTL traffic</synopsis>
95  </configOption>
96  <configOption name="udptlfecentries">
97  <synopsis>The number of error correction entries in a UDPTL packet</synopsis>
98  </configOption>
99  <configOption name="udptlfecspan">
100  <synopsis>The span over which parity is calculated for FEC in a UDPTL packet</synopsis>
101  </configOption>
102  <configOption name="use_even_ports">
103  <synopsis>Whether to only use even-numbered UDPTL ports</synopsis>
104  </configOption>
105  <configOption name="t38faxudpec">
106  <synopsis>Removed</synopsis>
107  </configOption>
108  <configOption name="t38faxmaxdatagram">
109  <synopsis>Removed</synopsis>
110  </configOption>
111  </configObject>
112  </configFile>
113  </configInfo>
114 ***/
115 
116 #define UDPTL_MTU 1200
117 
118 #if !defined(FALSE)
119 #define FALSE 0
120 #endif
121 #if !defined(TRUE)
122 #define TRUE (!FALSE)
123 #endif
124 
125 #define LOG_TAG(u) S_OR(u->tag, "no tag")
126 
127 #define DEFAULT_UDPTLSTART 4000
128 #define DEFAULT_UDPTLEND 4999
129 
130 static int udptldebug; /*!< Are we debugging? */
131 static struct ast_sockaddr udptldebugaddr; /*!< Debug packets to/from this host */
132 
133 #define LOCAL_FAX_MAX_DATAGRAM 1400
134 #define DEFAULT_FAX_MAX_DATAGRAM 400
135 #define FAX_MAX_DATAGRAM_LIMIT 1400
136 #define MAX_FEC_ENTRIES 5
137 #define MAX_FEC_SPAN 5
138 
139 #define UDPTL_BUF_MASK 15
140 
141 typedef struct {
142  int buf_len;
145 
146 typedef struct {
147  int buf_len;
149  unsigned int fec_len[MAX_FEC_ENTRIES];
151  unsigned int fec_span;
152  unsigned int fec_entries;
154 
155 /*! \brief Structure for an UDPTL session */
156 struct ast_udptl {
157  int fd;
158  char resp;
159  struct ast_frame f[16];
160  unsigned char rawdata[8192 + AST_FRIENDLY_OFFSET];
161  unsigned int lasteventseqn;
162  int nat;
163  int flags;
164  struct ast_sockaddr us;
165  struct ast_sockaddr them;
166  int *ioid;
168  struct io_context *io;
169  void *data;
170  char *tag;
172 
173  /*! This option indicates the error correction scheme used in transmitted UDPTL
174  * packets and expected in received UDPTL packets.
175  */
176  enum ast_t38_ec_modes error_correction_scheme;
177 
178  /*! This option indicates the number of error correction entries transmitted in
179  * UDPTL packets and expected in received UDPTL packets.
180  */
182 
183  /*! This option indicates the span of the error correction entries in transmitted
184  * UDPTL packets (FEC only).
185  */
186  unsigned int error_correction_span;
187 
188  /*! The maximum size UDPTL packet that can be accepted by
189  * the remote device.
190  */
192 
193  /*! The maximum size UDPTL packet that we are prepared to
194  * accept, or -1 if it hasn't been calculated since the last
195  * changes were applied to the UDPTL structure.
196  */
198 
199  /*! The maximum IFP that can be submitted for sending
200  * to the remote device. Calculated from far_max_datagram,
201  * error_correction_scheme and error_correction_entries,
202  * or -1 if it hasn't been calculated since the last
203  * changes were applied to the UDPTL structure.
204  */
206 
207  /*! The maximum IFP that the local endpoint is prepared
208  * to accept. Along with error_correction_scheme and
209  * error_correction_entries, used to calculate local_max_datagram.
210  */
212 
213  unsigned int tx_seq_no;
214  unsigned int rx_seq_no;
215 
218 };
219 
221  unsigned int start; /*< The UDPTL start port */
222  unsigned int end; /*< The UDPTL end port */
223  unsigned int fecentries;
224  unsigned int fecspan;
225  unsigned int nochecksums;
226  unsigned int use_even_ports;
227 };
228 
230 
231 struct udptl_config {
233 };
234 
235 static void *udptl_snapshot_alloc(void);
236 static int udptl_pre_apply_config(void);
237 
238 static struct aco_type general_option = {
239  .type = ACO_GLOBAL,
240  .name = "global",
241  .category_match = ACO_WHITELIST_EXACT,
242  .item_offset = offsetof(struct udptl_config, general),
243  .category = "general",
244 };
245 
246 static struct aco_type *general_options[] = ACO_TYPES(&general_option);
247 
248 static struct aco_file udptl_conf = {
249  .filename = "udptl.conf",
250  .types = ACO_TYPES(&general_option),
251 };
252 
253 CONFIG_INFO_CORE("udptl", cfg_info, globals, udptl_snapshot_alloc,
254  .files = ACO_FILES(&udptl_conf),
255  .pre_apply_config = udptl_pre_apply_config,
256 );
257 
258 static inline int udptl_debug_test_addr(const struct ast_sockaddr *addr)
259 {
260  if (udptldebug == 0)
261  return 0;
262 
264  return 1;
265  }
266 
268  return !ast_sockaddr_cmp(&udptldebugaddr, addr);
269  } else {
270  return !ast_sockaddr_cmp_addr(&udptldebugaddr, addr);
271  }
272 }
273 
274 static int decode_length(uint8_t *buf, unsigned int limit, unsigned int *len, unsigned int *pvalue)
275 {
276  if (*len >= limit)
277  return -1;
278  if ((buf[*len] & 0x80) == 0) {
279  *pvalue = buf[*len];
280  (*len)++;
281  return 0;
282  }
283  if ((buf[*len] & 0x40) == 0) {
284  if (*len == limit - 1)
285  return -1;
286  *pvalue = (buf[*len] & 0x3F) << 8;
287  (*len)++;
288  *pvalue |= buf[*len];
289  (*len)++;
290  return 0;
291  }
292  *pvalue = (buf[*len] & 0x3F) << 14;
293  (*len)++;
294  /* We have a fragment. Currently we don't process fragments. */
295  ast_debug(1, "UDPTL packet with length greater than 16K received, decoding will fail\n");
296  return 1;
297 }
298 /*- End of function --------------------------------------------------------*/
299 
300 static int decode_open_type(uint8_t *buf, unsigned int limit, unsigned int *len, const uint8_t **p_object, unsigned int *p_num_octets)
301 {
302  unsigned int octet_cnt = 0;
303 
304  if (decode_length(buf, limit, len, &octet_cnt) != 0)
305  return -1;
306 
307  /* Make sure the buffer contains at least the number of bits requested */
308  if ((*len + octet_cnt) > limit) {
309  return -1;
310  }
311 
312  *p_num_octets = octet_cnt;
313  *p_object = &buf[*len];
314  *len += octet_cnt;
315 
316  return 0;
317 }
318 /*- End of function --------------------------------------------------------*/
319 
320 static unsigned int encode_length(uint8_t *buf, unsigned int *len, unsigned int value)
321 {
322  unsigned int multiplier;
323 
324  if (value < 0x80) {
325  /* 1 octet */
326  buf[*len] = value;
327  (*len)++;
328  return value;
329  }
330  if (value < 0x4000) {
331  /* 2 octets */
332  /* Set the first bit of the first octet */
333  buf[*len] = ((0x8000 | value) >> 8) & 0xFF;
334  (*len)++;
335  buf[*len] = value & 0xFF;
336  (*len)++;
337  return value;
338  }
339  /* Fragmentation */
340  multiplier = (value < 0x10000) ? (value >> 14) : 4;
341  /* Set the first 2 bits of the octet */
342  buf[*len] = 0xC0 | multiplier;
343  (*len)++;
344  return multiplier << 14;
345 }
346 /*- End of function --------------------------------------------------------*/
347 
348 static int encode_open_type(const struct ast_udptl *udptl, uint8_t *buf, unsigned int buflen,
349  unsigned int *len, const uint8_t *data, unsigned int num_octets)
350 {
351  unsigned int enclen;
352  unsigned int octet_idx;
353  uint8_t zero_byte;
354 
355  /* If open type is of zero length, add a single zero byte (10.1) */
356  if (num_octets == 0) {
357  zero_byte = 0;
358  data = &zero_byte;
359  num_octets = 1;
360  }
361  /* Encode the open type */
362  for (octet_idx = 0; ; num_octets -= enclen, octet_idx += enclen) {
363  enclen = encode_length(buf, len, num_octets);
364  if (enclen + *len > buflen) {
365  ast_log(LOG_ERROR, "UDPTL (%s): Buffer overflow detected (%u + %u > %u)\n",
366  LOG_TAG(udptl), enclen, *len, buflen);
367  return -1;
368  }
369  if (enclen > 0) {
370  memcpy(&buf[*len], &data[octet_idx], enclen);
371  *len += enclen;
372  }
373  if (enclen >= num_octets)
374  break;
375  }
376 
377  return 0;
378 }
379 /*- End of function --------------------------------------------------------*/
380 
381 static int udptl_rx_packet(struct ast_udptl *s, uint8_t *buf, unsigned int len)
382 {
383  int stat1;
384  int stat2;
385  int i;
386  unsigned int ptr; /* an index that keeps track of how much of the UDPTL packet has been processed */
387  int seq_no;
388  const uint8_t *ifp = NULL;
389  const uint8_t *data = NULL;
390  unsigned int ifp_len = 0;
391  int repaired[16];
392  const uint8_t *bufs[ARRAY_LEN(s->f) - 1];
393  unsigned int lengths[ARRAY_LEN(s->f) - 1];
394  int span;
395  int entries;
396  int ifp_no;
397 
398  ptr = 0;
399  ifp_no = 0;
400  memset(&s->f[0], 0, sizeof(s->f[0]));
401 
402  /* Decode seq_number */
403  if (ptr + 2 > len)
404  return -1;
405  seq_no = (buf[0] << 8) | buf[1];
406  ptr += 2;
407 
408  /* UDPTL sequence numbers are 16 bit so after 0xFFFF comes
409  0 which breaks all packet recovery logic. To fix this
410  if we see that next expected packet (rx_seq_no) is close
411  to or beyond the wrap around limit & the received packet
412  is still near zero, then we 'unwrap' the received seqno
413  so it has the value it would have had. After a 16
414  packet grace period (there shouldn't be more than
415  that many recovery packets) we wrap the expected
416  sequence number around and things can return back
417  to normal */
418  if (seq_no < 0x000F && s->rx_seq_no > 0xFFF0) {
419  /* received seq_no has wrapped adjust it */
420  seq_no += 0x10000;
421  } else {
422  /* otherwise make sure expected rx_seq_no is properly wrapped */
423  s->rx_seq_no &= 0xFFFF;
424  }
425 
426  /* Break out the primary packet */
427  if ((stat1 = decode_open_type(buf, len, &ptr, &ifp, &ifp_len)) != 0)
428  return -1;
429  /* Decode error_recovery */
430  if (ptr + 1 > len)
431  return -1;
432  if ((buf[ptr++] & 0x80) == 0) {
433  /* Secondary packet mode for error recovery */
434  if (seq_no > s->rx_seq_no) {
435  /* We received a later packet than we expected, so we need to check if we can fill in the gap from the
436  secondary packets. */
437  int total_count = 0;
438  do {
439  unsigned int count;
440  if ((stat2 = decode_length(buf, len, &ptr, &count)) < 0)
441  return -1;
442  for (i = 0; i < count && total_count + i < ARRAY_LEN(bufs); i++) {
443  if ((stat1 = decode_open_type(buf, len, &ptr, &bufs[total_count + i], &lengths[total_count + i])) != 0) {
444  return -1;
445  }
446  /* valid secondaries can contain zero-length packets that should be ignored */
447  if (!bufs[total_count + i] || !lengths[total_count + i]) {
448  /* drop the count of items to process and reuse the buffers that were just set */
449  i--;
450  count--;
451  }
452  }
453  total_count += i;
454  }
455  while (stat2 > 0 && total_count < ARRAY_LEN(bufs));
456  /* Step through in reverse order, so we go oldest to newest */
457  for (i = total_count; i > 0; i--) {
458  if (seq_no - i >= s->rx_seq_no) {
459  /* This one wasn't seen before */
460  /* Decode the secondary IFP packet */
461  ast_debug(3, "Recovering lost packet via secondary %d, len %u\n", seq_no - i, lengths[i - 1]);
462  s->f[ifp_no].frametype = AST_FRAME_MODEM;
463  s->f[ifp_no].subclass.integer = AST_MODEM_T38;
464 
465  s->f[ifp_no].mallocd = 0;
466  s->f[ifp_no].seqno = seq_no - i;
467  s->f[ifp_no].datalen = lengths[i - 1];
468  s->f[ifp_no].data.ptr = (uint8_t *) bufs[i - 1];
469  s->f[ifp_no].offset = 0;
470  s->f[ifp_no].src = "UDPTL";
471  if (ifp_no > 0)
472  AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
473  AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
474  ifp_no++;
475  }
476  }
477  }
478  }
479  else
480  {
481  int j;
482  int l;
483  int x;
484  /* FEC mode for error recovery */
485  /* Our buffers cannot tolerate overlength IFP packets in FEC mode */
486  if (ifp_len > LOCAL_FAX_MAX_DATAGRAM)
487  return -1;
488  /* Update any missed slots in the buffer */
489  for ( ; seq_no > s->rx_seq_no; s->rx_seq_no++) {
490  x = s->rx_seq_no & UDPTL_BUF_MASK;
491  s->rx[x].buf_len = -1;
492  s->rx[x].fec_len[0] = 0;
493  s->rx[x].fec_span = 0;
494  s->rx[x].fec_entries = 0;
495  }
496 
497  x = seq_no & UDPTL_BUF_MASK;
498 
499  memset(repaired, 0, sizeof(repaired));
500 
501  /* Save the new IFP packet */
502  memcpy(s->rx[x].buf, ifp, ifp_len);
503  s->rx[x].buf_len = ifp_len;
504  repaired[x] = TRUE;
505 
506  /* Decode the FEC packets */
507  /* The span is defined as an unconstrained integer, but will never be more
508  than a small value. */
509  if (ptr + 2 > len)
510  return -1;
511  if (buf[ptr++] != 1)
512  return -1;
513  span = buf[ptr++];
514  s->rx[x].fec_span = span;
515 
516  /* The number of entries is defined as a length, but will only ever be a small
517  value. Treat it as such. */
518  if (ptr + 1 > len)
519  return -1;
520  entries = buf[ptr++];
521  if (entries > MAX_FEC_ENTRIES) {
522  return -1;
523  }
524  s->rx[x].fec_entries = entries;
525 
526  /* Decode the elements */
527  for (i = 0; i < entries; i++) {
528  if ((stat1 = decode_open_type(buf, len, &ptr, &data, &s->rx[x].fec_len[i])) != 0)
529  return -1;
530  if (s->rx[x].fec_len[i] > LOCAL_FAX_MAX_DATAGRAM)
531  return -1;
532 
533  /* Save the new FEC data */
534  memcpy(s->rx[x].fec[i], data, s->rx[x].fec_len[i]);
535 #if 0
536  fprintf(stderr, "FEC: ");
537  for (j = 0; j < s->rx[x].fec_len[i]; j++)
538  fprintf(stderr, "%02hhX ", data[j]);
539  fprintf(stderr, "\n");
540 #endif
541  }
542 
543  /* See if we can reconstruct anything which is missing */
544  /* TODO: this does not comprehensively hunt back and repair everything that is possible */
545  for (l = x; l != ((x - (16 - span*entries)) & UDPTL_BUF_MASK); l = (l - 1) & UDPTL_BUF_MASK) {
546  int m;
547  if (s->rx[l].fec_len[0] <= 0)
548  continue;
549  for (m = 0; m < s->rx[l].fec_entries; m++) {
550  int k;
551  int which;
552  int limit = (l + m) & UDPTL_BUF_MASK;
553 
554  /* only repair buffers that actually exist! */
555  if (seq_no <= (s->rx[l].fec_span * s->rx[l].fec_entries) - m) {
556  continue;
557  }
558 
559  for (which = -1, k = (limit - s->rx[l].fec_span * s->rx[l].fec_entries) & UDPTL_BUF_MASK; k != limit; k = (k + s->rx[l].fec_entries) & UDPTL_BUF_MASK) {
560  if (s->rx[k].buf_len <= 0)
561  which = (which == -1) ? k : -2;
562  }
563  if (which >= 0) {
564  /* Repairable */
565  for (j = 0; j < s->rx[l].fec_len[m]; j++) {
566  s->rx[which].buf[j] = s->rx[l].fec[m][j];
567  for (k = (limit - s->rx[l].fec_span * s->rx[l].fec_entries) & UDPTL_BUF_MASK; k != limit; k = (k + s->rx[l].fec_entries) & UDPTL_BUF_MASK)
568  s->rx[which].buf[j] ^= (s->rx[k].buf_len > j) ? s->rx[k].buf[j] : 0;
569  }
570  s->rx[which].buf_len = s->rx[l].fec_len[m];
571  repaired[which] = TRUE;
572  }
573  }
574  }
575  /* Now play any new packets forwards in time */
576  for (l = (x + 1) & UDPTL_BUF_MASK, j = seq_no - UDPTL_BUF_MASK; l != x; l = (l + 1) & UDPTL_BUF_MASK, j++) {
577  if (repaired[l]) {
578  //fprintf(stderr, "Fixed packet %d, len %d\n", j, l);
579  s->f[ifp_no].frametype = AST_FRAME_MODEM;
580  s->f[ifp_no].subclass.integer = AST_MODEM_T38;
581 
582  s->f[ifp_no].mallocd = 0;
583  s->f[ifp_no].seqno = j;
584  s->f[ifp_no].datalen = s->rx[l].buf_len;
585  s->f[ifp_no].data.ptr = s->rx[l].buf;
586  s->f[ifp_no].offset = 0;
587  s->f[ifp_no].src = "UDPTL";
588  if (ifp_no > 0)
589  AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
590  AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
591  ifp_no++;
592  }
593  }
594  }
595 
596  /* If packets are received out of sequence, we may have already processed this packet from the error
597  recovery information in a packet already received. */
598  if (seq_no >= s->rx_seq_no) {
599  /* Decode the primary IFP packet */
600  s->f[ifp_no].frametype = AST_FRAME_MODEM;
601  s->f[ifp_no].subclass.integer = AST_MODEM_T38;
602 
603  s->f[ifp_no].mallocd = 0;
604  s->f[ifp_no].seqno = seq_no;
605  s->f[ifp_no].datalen = ifp_len;
606  s->f[ifp_no].data.ptr = (uint8_t *) ifp;
607  s->f[ifp_no].offset = 0;
608  s->f[ifp_no].src = "UDPTL";
609  if (ifp_no > 0)
610  AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
611  AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
612 
613  ifp_no++;
614  }
615 
616  s->rx_seq_no = seq_no + 1;
617  return ifp_no;
618 }
619 /*- End of function --------------------------------------------------------*/
620 
621 static int udptl_build_packet(struct ast_udptl *s, uint8_t *buf, unsigned int buflen, uint8_t *ifp, unsigned int ifp_len)
622 {
623  uint8_t fec[LOCAL_FAX_MAX_DATAGRAM * 2] = { 0, };
624  int i;
625  int j;
626  int seq;
627  int entry;
628  int entries;
629  int span;
630  int m;
631  unsigned int len;
632  int limit;
633  int high_tide;
634 
635  seq = s->tx_seq_no & 0xFFFF;
636 
637  /* Map the sequence number to an entry in the circular buffer */
638  entry = seq & UDPTL_BUF_MASK;
639 
640  /* We save the message in a circular buffer, for generating FEC or
641  redundancy sets later on. */
642  s->tx[entry].buf_len = ifp_len;
643  memcpy(s->tx[entry].buf, ifp, ifp_len);
644 
645  /* Build the UDPTLPacket */
646 
647  len = 0;
648  /* Encode the sequence number */
649  buf[len++] = (seq >> 8) & 0xFF;
650  buf[len++] = seq & 0xFF;
651 
652  /* Encode the primary IFP packet */
653  if (encode_open_type(s, buf, buflen, &len, ifp, ifp_len) < 0)
654  return -1;
655 
656  /* Encode the appropriate type of error recovery information */
657  switch (s->error_correction_scheme)
658  {
660  /* Encode the error recovery type */
661  buf[len++] = 0x00;
662  /* The number of entries will always be zero, so it is pointless allowing
663  for the fragmented case here. */
664  encode_length(buf, &len, 0);
665  break;
667  /* Encode the error recovery type */
668  buf[len++] = 0x00;
670  entries = s->error_correction_entries;
671  else
672  entries = s->tx_seq_no;
673  /* The number of entries will always be small, so it is pointless allowing
674  for the fragmented case here. */
675  encode_length(buf, &len, entries);
676  /* Encode the elements */
677  for (i = 0; i < entries; i++) {
678  j = (entry - i - 1) & UDPTL_BUF_MASK;
679  if (encode_open_type(s, buf, buflen, &len, s->tx[j].buf, s->tx[j].buf_len) < 0) {
680  ast_debug(1, "UDPTL (%s): Encoding failed at i=%d, j=%d\n",
681  LOG_TAG(s), i, j);
682  return -1;
683  }
684  }
685  break;
687  span = s->error_correction_span;
688  entries = s->error_correction_entries;
689  if (seq < s->error_correction_span*s->error_correction_entries) {
690  /* In the initial stages, wind up the FEC smoothly */
691  entries = seq/s->error_correction_span;
692  if (seq < s->error_correction_span)
693  span = 0;
694  }
695  /* Encode the error recovery type */
696  buf[len++] = 0x80;
697  /* Span is defined as an inconstrained integer, which it dumb. It will only
698  ever be a small value. Treat it as such. */
699  buf[len++] = 1;
700  buf[len++] = span;
701  /* The number of entries is defined as a length, but will only ever be a small
702  value. Treat it as such. */
703  buf[len++] = entries;
704  for (m = 0; m < entries; m++) {
705  /* Make an XOR'ed entry the maximum length */
706  limit = (entry + m) & UDPTL_BUF_MASK;
707  high_tide = 0;
708  for (i = (limit - span*entries) & UDPTL_BUF_MASK; i != limit; i = (i + entries) & UDPTL_BUF_MASK) {
709  if (high_tide < s->tx[i].buf_len) {
710  for (j = 0; j < high_tide; j++)
711  fec[j] ^= s->tx[i].buf[j];
712  for ( ; j < s->tx[i].buf_len; j++)
713  fec[j] = s->tx[i].buf[j];
714  high_tide = s->tx[i].buf_len;
715  } else {
716  for (j = 0; j < s->tx[i].buf_len; j++)
717  fec[j] ^= s->tx[i].buf[j];
718  }
719  }
720  if (encode_open_type(s, buf, buflen, &len, fec, high_tide) < 0)
721  return -1;
722  }
723  break;
724  }
725 
726  s->tx_seq_no++;
727  return len;
728 }
729 
730 int ast_udptl_fd(const struct ast_udptl *udptl)
731 {
732  return udptl->fd;
733 }
734 
735 void ast_udptl_set_data(struct ast_udptl *udptl, void *data)
736 {
737  udptl->data = data;
738 }
739 
741 {
742  udptl->callback = callback;
743 }
744 
745 void ast_udptl_setnat(struct ast_udptl *udptl, int nat)
746 {
747  udptl->nat = nat;
748 }
749 
750 static int udptlread(int *id, int fd, short events, void *cbdata)
751 {
752  struct ast_udptl *udptl = cbdata;
753  struct ast_frame *f;
754 
755  if ((f = ast_udptl_read(udptl))) {
756  if (udptl->callback)
757  udptl->callback(udptl, f, udptl->data);
758  }
759  return 1;
760 }
761 
762 struct ast_frame *ast_udptl_read(struct ast_udptl *udptl)
763 {
764  int res;
765  struct ast_sockaddr addr;
766  uint8_t *buf;
767 
768  buf = udptl->rawdata + AST_FRIENDLY_OFFSET;
769 
770  /* Cache where the header will go */
771  res = ast_recvfrom(udptl->fd,
772  buf,
773  sizeof(udptl->rawdata) - AST_FRIENDLY_OFFSET,
774  0,
775  &addr);
776  if (res < 0) {
777  if (errno != EAGAIN)
778  ast_log(LOG_WARNING, "UDPTL (%s): read error: %s\n",
779  LOG_TAG(udptl), strerror(errno));
780  ast_assert(errno != EBADF);
781  return &ast_null_frame;
782  }
783 
784  /* Ignore if the other side hasn't been given an address yet. */
785  if (ast_sockaddr_isnull(&udptl->them)) {
786  return &ast_null_frame;
787  }
788 
789  /*
790  * If early media isn't turned on for the channel driver, it's going to
791  * drop this frame. By that time though, udptl has already incremented
792  * the expected sequence number so if the CPE re-sends, the second frame
793  * will be dropped as a dup even though the first frame never went through.
794  * So we drop the frame here if the channel isn't up. 'tag' is set by the
795  * channel drivers on T38_ENABLED or T38_PEER_REINVITE.
796  */
797  if (udptl->tag == NULL) {
798  return &ast_null_frame;
799  }
800 
801  if (udptl->nat) {
802  /* Send to whoever sent to us */
803  if (ast_sockaddr_cmp(&udptl->them, &addr)) {
804  ast_sockaddr_copy(&udptl->them, &addr);
805  ast_debug(1, "UDPTL (%s): NAT, Using address %s\n",
806  LOG_TAG(udptl), ast_sockaddr_stringify(&udptl->them));
807  }
808  }
809 
810  if (udptl_debug_test_addr(&addr)) {
811  int seq_no;
812 
813  /* Decode sequence number just for verbose message. */
814  if (res < 2) {
815  /* Short packet. */
816  seq_no = -1;
817  } else {
818  seq_no = (buf[0] << 8) | buf[1];
819  }
820 
821  ast_verb(1, "UDPTL (%s): packet from %s (seq %d, len %d)\n",
822  LOG_TAG(udptl), ast_sockaddr_stringify(&addr), seq_no, res);
823  }
824  if (udptl_rx_packet(udptl, buf, res) < 1) {
825  return &ast_null_frame;
826  }
827 
828  return &udptl->f[0];
829 }
830 
831 static void calculate_local_max_datagram(struct ast_udptl *udptl)
832 {
833  unsigned int new_max = 0;
834 
835  if (udptl->local_max_ifp == -1) {
836  ast_log(LOG_WARNING, "UDPTL (%s): Cannot calculate local_max_datagram before local_max_ifp has been set.\n",
837  LOG_TAG(udptl));
838  udptl->local_max_datagram = -1;
839  return;
840  }
841 
842  /* calculate the amount of space required to receive an IFP
843  * of the maximum size supported by the application/endpoint
844  * that we are delivering them to (local endpoint), and add
845  * the amount of space required to support the selected
846  * error correction mode
847  */
848  switch (udptl->error_correction_scheme) {
850  /* need room for sequence number, length indicator, redundancy
851  * indicator and following length indicator
852  */
853  new_max = 5 + udptl->local_max_ifp;
854  break;
856  /* need room for sequence number, length indicators, plus
857  * room for up to 3 redundancy packets
858  */
859  new_max = 5 + udptl->local_max_ifp + 2 + (3 * udptl->local_max_ifp);
860  break;
862  /* need room for sequence number, length indicators and a
863  * a single IFP of the maximum size expected
864  */
865  new_max = 5 + udptl->local_max_ifp + 4 + udptl->local_max_ifp;
866  break;
867  }
868  /* add 5% extra space for insurance, but no larger than LOCAL_FAX_MAX_DATAGRAM */
869  udptl->local_max_datagram = MIN(new_max * 1.05, LOCAL_FAX_MAX_DATAGRAM);
870 }
871 
872 static void calculate_far_max_ifp(struct ast_udptl *udptl)
873 {
874  unsigned new_max = 0;
875 
876  if (udptl->far_max_datagram == -1) {
877  ast_log(LOG_WARNING, "UDPTL (%s): Cannot calculate far_max_ifp before far_max_datagram has been set.\n",
878  LOG_TAG(udptl));
879  udptl->far_max_ifp = -1;
880  return;
881  }
882 
883  /* the goal here is to supply the local endpoint (application
884  * or bridged channel) a maximum IFP value that will allow it
885  * to effectively and efficiently transfer image data at its
886  * selected bit rate, taking into account the selected error
887  * correction mode, but without overrunning the far endpoint's
888  * datagram buffer. this is complicated by the fact that some
889  * far endpoints send us bogus (small) max datagram values,
890  * which would result in either buffer overrun or no error
891  * correction. we try to accomodate those, but if the supplied
892  * value is too small to do so, we'll emit warning messages and
893  * the user will have to use configuration options to override
894  * the max datagram value supplied by the far endpoint.
895  */
896  switch (udptl->error_correction_scheme) {
898  /* need room for sequence number, length indicator, redundancy
899  * indicator and following length indicator
900  */
901  new_max = udptl->far_max_datagram - 5;
902  break;
904  /* for this case, we'd like to send as many error correction entries
905  * as possible (up to the number we're configured for), but we'll settle
906  * for sending fewer if the configured number would cause the
907  * calculated max IFP to be too small for effective operation
908  *
909  * need room for sequence number, length indicators and the
910  * configured number of redundant packets
911  *
912  * note: we purposely don't allow error_correction_entries to drop to
913  * zero in this loop; we'd rather send smaller IFPs (and thus reduce
914  * the image data transfer rate) than sacrifice redundancy completely
915  */
916  for (;;) {
917  new_max = (udptl->far_max_datagram - 8) / (udptl->error_correction_entries + 1);
918 
919  if ((new_max < 80) && (udptl->error_correction_entries > 1)) {
920  /* the max ifp is not large enough, subtract an
921  * error correction entry and calculate again
922  * */
923  --udptl->error_correction_entries;
924  } else {
925  break;
926  }
927  }
928  break;
930  /* need room for sequence number, length indicators and a
931  * a single IFP of the maximum size expected
932  */
933  new_max = (udptl->far_max_datagram - 10) / 2;
934  break;
935  }
936  /* subtract 5% of space for insurance */
937  udptl->far_max_ifp = new_max * 0.95;
938 }
939 
941 {
942  return udptl->error_correction_scheme;
943 }
944 
946 {
947  udptl->error_correction_scheme = ec;
948  switch (ec) {
951  if (udptl->error_correction_entries == 0) {
952  udptl->error_correction_entries = 3;
953  }
954  if (udptl->error_correction_span == 0) {
955  udptl->error_correction_span = 3;
956  }
957  break;
960  if (udptl->error_correction_entries == 0) {
961  udptl->error_correction_entries = 3;
962  }
963  break;
964  default:
965  /* nothing to do */
966  break;
967  };
968  /* reset calculated values so they'll be computed again */
969  udptl->local_max_datagram = -1;
970  udptl->far_max_ifp = -1;
971 }
972 
973 void ast_udptl_set_local_max_ifp(struct ast_udptl *udptl, unsigned int max_ifp)
974 {
975  /* make sure max_ifp is a positive value since a cast will take place when
976  * when setting local_max_ifp */
977  if ((signed int) max_ifp > 0) {
978  udptl->local_max_ifp = max_ifp;
979  /* reset calculated values so they'll be computed again */
980  udptl->local_max_datagram = -1;
981  }
982 }
983 
984 unsigned int ast_udptl_get_local_max_datagram(struct ast_udptl *udptl)
985 {
986  if (udptl->local_max_datagram == -1) {
988  }
989 
990  /* this function expects a unsigned value in return. */
991  if (udptl->local_max_datagram < 0) {
992  return 0;
993  }
994  return udptl->local_max_datagram;
995 }
996 
997 void ast_udptl_set_far_max_datagram(struct ast_udptl *udptl, unsigned int max_datagram)
998 {
999  if (!max_datagram || (max_datagram > FAX_MAX_DATAGRAM_LIMIT)) {
1001  } else {
1002  udptl->far_max_datagram = max_datagram;
1003  }
1004  /* reset calculated values so they'll be computed again */
1005  udptl->far_max_ifp = -1;
1006 }
1007 
1008 unsigned int ast_udptl_get_far_max_datagram(const struct ast_udptl *udptl)
1009 {
1010  if (udptl->far_max_datagram < 0) {
1011  return 0;
1012  }
1013  return udptl->far_max_datagram;
1014 }
1015 
1016 unsigned int ast_udptl_get_far_max_ifp(struct ast_udptl *udptl)
1017 {
1018  if (udptl->far_max_ifp == -1) {
1019  calculate_far_max_ifp(udptl);
1020  }
1021 
1022  if (udptl->far_max_ifp < 0) {
1023  return 0;
1024  }
1025  return udptl->far_max_ifp;
1026 }
1027 
1028 struct ast_udptl *ast_udptl_new_with_bindaddr(struct ast_sched_context *sched, struct io_context *io, int callbackmode, struct ast_sockaddr *addr)
1029 {
1030  struct ast_udptl *udptl;
1031  int x;
1032  int startplace;
1033  int i;
1035 
1036  if (!cfg || !cfg->general) {
1037  ast_log(LOG_ERROR, "Could not access global udptl options!\n");
1038  return NULL;
1039  }
1040 
1041  if (!(udptl = ast_calloc(1, sizeof(*udptl)))) {
1042  return NULL;
1043  }
1044 
1045  udptl->error_correction_span = cfg->general->fecspan;
1046  udptl->error_correction_entries = cfg->general->fecentries;
1047 
1048  udptl->far_max_datagram = -1;
1049  udptl->far_max_ifp = -1;
1050  udptl->local_max_ifp = -1;
1051  udptl->local_max_datagram = -1;
1052 
1053  for (i = 0; i <= UDPTL_BUF_MASK; i++) {
1054  udptl->rx[i].buf_len = -1;
1055  udptl->tx[i].buf_len = -1;
1056  }
1057 
1058  if ((udptl->fd = ast_socket_nonblock(ast_sockaddr_is_ipv6(addr) ?
1059  AF_INET6 : AF_INET, SOCK_DGRAM, 0)) < 0) {
1060  ast_free(udptl);
1061  ast_log(LOG_WARNING, "Unable to allocate socket: %s\n", strerror(errno));
1062  return NULL;
1063  }
1064 
1065 #ifdef SO_NO_CHECK
1066  if (cfg->general->nochecksums)
1067  setsockopt(udptl->fd, SOL_SOCKET, SO_NO_CHECK, &cfg->general->nochecksums, sizeof(cfg->general->nochecksums));
1068 #endif
1069 
1070  /* Find us a place */
1071  x = (cfg->general->start == cfg->general->end) ? cfg->general->start : (ast_random() % (cfg->general->end - cfg->general->start)) + cfg->general->start;
1072  if (cfg->general->use_even_ports && (x & 1)) {
1073  ++x;
1074  }
1075  startplace = x;
1076  for (;;) {
1077  ast_sockaddr_copy(&udptl->us, addr);
1078  ast_sockaddr_set_port(&udptl->us, x);
1079  if (ast_bind(udptl->fd, &udptl->us) == 0) {
1080  break;
1081  }
1082  if (errno != EADDRINUSE && errno != EACCES) {
1083  ast_log(LOG_WARNING, "Unexpected bind error: %s\n", strerror(errno));
1084  close(udptl->fd);
1085  ast_free(udptl);
1086  return NULL;
1087  }
1088  if (cfg->general->use_even_ports) {
1089  x += 2;
1090  } else {
1091  ++x;
1092  }
1093  if (x > cfg->general->end)
1094  x = cfg->general->start;
1095  if (x == startplace) {
1096  ast_log(LOG_WARNING, "No UDPTL ports remaining\n");
1097  close(udptl->fd);
1098  ast_free(udptl);
1099  return NULL;
1100  }
1101  }
1102  if (io && sched && callbackmode) {
1103  /* Operate this one in a callback mode */
1104  udptl->sched = sched;
1105  udptl->io = io;
1106  udptl->ioid = ast_io_add(udptl->io, udptl->fd, udptlread, AST_IO_IN, udptl);
1107  }
1108 
1109  return udptl;
1110 }
1111 
1112 void ast_udptl_set_tag(struct ast_udptl *udptl, const char *format, ...)
1113 {
1114  va_list ap;
1115 
1116  ast_free(udptl->tag);
1117  udptl->tag = NULL;
1118  va_start(ap, format);
1119  if (ast_vasprintf(&udptl->tag, format, ap) == -1) {
1120  udptl->tag = NULL;
1121  }
1122  va_end(ap);
1123 }
1124 
1125 int ast_udptl_setqos(struct ast_udptl *udptl, unsigned int tos, unsigned int cos)
1126 {
1127  return ast_set_qos(udptl->fd, tos, cos, "UDPTL");
1128 }
1129 
1130 void ast_udptl_set_peer(struct ast_udptl *udptl, const struct ast_sockaddr *them)
1131 {
1132  ast_sockaddr_copy(&udptl->them, them);
1133 }
1134 
1135 void ast_udptl_get_peer(const struct ast_udptl *udptl, struct ast_sockaddr *them)
1136 {
1137  ast_sockaddr_copy(them, &udptl->them);
1138 }
1139 
1140 void ast_udptl_get_us(const struct ast_udptl *udptl, struct ast_sockaddr *us)
1141 {
1142  ast_sockaddr_copy(us, &udptl->us);
1143 }
1144 
1145 void ast_udptl_stop(struct ast_udptl *udptl)
1146 {
1147  ast_sockaddr_setnull(&udptl->them);
1148 }
1149 
1150 void ast_udptl_destroy(struct ast_udptl *udptl)
1151 {
1152  if (udptl->ioid)
1153  ast_io_remove(udptl->io, udptl->ioid);
1154  if (udptl->fd > -1)
1155  close(udptl->fd);
1156  if (udptl->tag)
1157  ast_free(udptl->tag);
1158  ast_free(udptl);
1159 }
1160 
1161 int ast_udptl_write(struct ast_udptl *s, struct ast_frame *f)
1162 {
1163  unsigned int seq;
1164  unsigned int len = f->datalen;
1165  /* if no max datagram size is provided, use default value */
1166  const int bufsize = (s->far_max_datagram > 0) ? s->far_max_datagram : DEFAULT_FAX_MAX_DATAGRAM;
1167  uint8_t buf[bufsize];
1168 
1169  memset(buf, 0, sizeof(buf));
1170 
1171  /* If we have no peer, return immediately */
1172  if (ast_sockaddr_isnull(&s->them)) {
1173  return 0;
1174  }
1175 
1176  /* If there is no data length, return immediately */
1177  if (f->datalen == 0)
1178  return 0;
1179 
1180  if ((f->frametype != AST_FRAME_MODEM) ||
1181  (f->subclass.integer != AST_MODEM_T38)) {
1182  ast_log(LOG_WARNING, "UDPTL (%s): UDPTL can only send T.38 data.\n",
1183  LOG_TAG(s));
1184  return -1;
1185  }
1186 
1187  if (len > s->far_max_ifp) {
1189  "UDPTL (%s): UDPTL asked to send %u bytes of IFP when far end only prepared to accept %d bytes; data loss will occur."
1190  "You may need to override the T38FaxMaxDatagram value for this endpoint in the channel driver configuration.\n",
1191  LOG_TAG(s), len, s->far_max_ifp);
1192  len = s->far_max_ifp;
1193  }
1194 
1195  /* Save seq_no for debug output because udptl_build_packet increments it */
1196  seq = s->tx_seq_no & 0xFFFF;
1197 
1198  /* Cook up the UDPTL packet, with the relevant EC info. */
1199  len = udptl_build_packet(s, buf, sizeof(buf), f->data.ptr, len);
1200 
1201  if ((signed int) len > 0 && !ast_sockaddr_isnull(&s->them)) {
1202  if (ast_sendto(s->fd, buf, len, 0, &s->them) < 0) {
1203  ast_log(LOG_NOTICE, "UDPTL (%s): Transmission error to %s: %s\n",
1204  LOG_TAG(s), ast_sockaddr_stringify(&s->them), strerror(errno));
1205  }
1206  if (udptl_debug_test_addr(&s->them)) {
1207  ast_verb(1, "UDPTL (%s): packet to %s (seq %u, len %u)\n",
1208  LOG_TAG(s), ast_sockaddr_stringify(&s->them), seq, len);
1209  }
1210  }
1211 
1212  return 0;
1213 }
1214 
1215 static char *handle_cli_udptl_set_debug(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
1216 {
1217  switch (cmd) {
1218  case CLI_INIT:
1219  e->command = "udptl set debug {on|off|ip}";
1220  e->usage =
1221  "Usage: udptl set debug {on|off|ip host[:port]}\n"
1222  " Enable or disable dumping of UDPTL packets.\n"
1223  " If ip is specified, limit the dumped packets to those to and from\n"
1224  " the specified 'host' with optional port.\n";
1225  return NULL;
1226  case CLI_GENERATE:
1227  return NULL;
1228  }
1229 
1230  if (a->argc < 4 || a->argc > 5)
1231  return CLI_SHOWUSAGE;
1232 
1233  if (a->argc == 4) {
1234  if (!strncasecmp(a->argv[3], "on", 2)) {
1235  udptldebug = 1;
1236  memset(&udptldebugaddr, 0, sizeof(udptldebugaddr));
1237  ast_cli(a->fd, "UDPTL Debugging Enabled\n");
1238  } else if (!strncasecmp(a->argv[3], "off", 3)) {
1239  udptldebug = 0;
1240  ast_cli(a->fd, "UDPTL Debugging Disabled\n");
1241  } else {
1242  return CLI_SHOWUSAGE;
1243  }
1244  } else {
1245  struct ast_sockaddr *addrs;
1246  if (strncasecmp(a->argv[3], "ip", 2))
1247  return CLI_SHOWUSAGE;
1248  if (!ast_sockaddr_resolve(&addrs, a->argv[4], 0, 0)) {
1249  return CLI_SHOWUSAGE;
1250  }
1251  ast_sockaddr_copy(&udptldebugaddr, &addrs[0]);
1252  ast_cli(a->fd, "UDPTL Debugging Enabled for IP: %s\n", ast_sockaddr_stringify(&udptldebugaddr));
1253  udptldebug = 1;
1254  ast_free(addrs);
1255  }
1256 
1257  return CLI_SUCCESS;
1258 }
1259 
1260 static char *handle_cli_show_config(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
1261 {
1262  RAII_VAR(struct udptl_config *, cfg, NULL, ao2_cleanup);
1263 
1264  switch (cmd) {
1265  case CLI_INIT:
1266  e->command = "udptl show config";
1267  e->usage =
1268  "Usage: udptl show config\n"
1269  " Display UDPTL configuration options\n";
1270  return NULL;
1271  case CLI_GENERATE:
1272  return NULL;
1273  }
1274 
1275  if (!(cfg = ao2_global_obj_ref(globals))) {
1276  return CLI_FAILURE;
1277  }
1278 
1279  ast_cli(a->fd, "UDPTL Global options\n");
1280  ast_cli(a->fd, "--------------------\n");
1281  ast_cli(a->fd, "udptlstart: %u\n", cfg->general->start);
1282  ast_cli(a->fd, "udptlend: %u\n", cfg->general->end);
1283  ast_cli(a->fd, "udptlfecentries: %u\n", cfg->general->fecentries);
1284  ast_cli(a->fd, "udptlfecspan: %u\n", cfg->general->fecspan);
1285  ast_cli(a->fd, "use_even_ports: %s\n", AST_CLI_YESNO(cfg->general->use_even_ports));
1286  ast_cli(a->fd, "udptlchecksums: %s\n", AST_CLI_YESNO(!cfg->general->nochecksums));
1287 
1288  return CLI_SUCCESS;
1289 }
1290 
1291 static struct ast_cli_entry cli_udptl[] = {
1292  AST_CLI_DEFINE(handle_cli_udptl_set_debug, "Enable/Disable UDPTL debugging"),
1293  AST_CLI_DEFINE(handle_cli_show_config, "Show UDPTL config options"),
1294 };
1295 
1296 static void udptl_config_destructor(void *obj)
1297 {
1298  struct udptl_config *cfg = obj;
1299  ao2_cleanup(cfg->general);
1300 }
1301 
1302 static void *udptl_snapshot_alloc(void)
1303 {
1304  struct udptl_config *cfg;
1305 
1306  if (!(cfg = ao2_alloc(sizeof(*cfg), udptl_config_destructor))) {
1307  return NULL;
1308  }
1309  if (!(cfg->general = ao2_alloc(sizeof(*cfg->general), NULL))) {
1310  ao2_ref(cfg, -1);
1311  return NULL;
1312  }
1313 
1314  return cfg;
1315 }
1316 
1317 static int removed_options_handler(const struct aco_option *opt, struct ast_variable *var, void *obj)
1318 {
1319  if (!strcasecmp(var->name, "t38faxudpec")) {
1320  ast_log(LOG_WARNING, "t38faxudpec in udptl.conf is no longer supported; use the t38pt_udptl configuration option in sip.conf instead.\n");
1321  } else if (!strcasecmp(var->name, "t38faxmaxdatagram")) {
1322  ast_log(LOG_WARNING, "t38faxmaxdatagram in udptl.conf is no longer supported; value is now supplied by T.38 applications.\n");
1323  }
1324  return 0;
1325 }
1326 
1327 static void __ast_udptl_reload(int reload)
1328 {
1329  if (aco_process_config(&cfg_info, reload) == ACO_PROCESS_ERROR) {
1330  if (!reload) {
1331  RAII_VAR(struct udptl_config *, udptl_cfg, udptl_snapshot_alloc(), ao2_cleanup);
1332 
1333  if (aco_set_defaults(&general_option, "general", udptl_cfg->general)) {
1334  ast_log(LOG_ERROR, "Failed to load udptl.conf and failed to initialize defaults.\n");
1335  return;
1336  }
1337 
1338  ast_log(LOG_NOTICE, "Could not load udptl config; using defaults\n");
1340  }
1341  }
1342 }
1343 
1344 static int udptl_pre_apply_config(void) {
1345  struct udptl_config *cfg = aco_pending_config(&cfg_info);
1346 
1347  if (!cfg->general) {
1348  return -1;
1349  }
1350 
1351 #ifndef SO_NO_CHECK
1352  if (cfg->general->nochecksums) {
1353  ast_log(LOG_WARNING, "Disabling UDPTL checksums is not supported on this operating system!\n");
1354  cfg->general->nochecksums = 0;
1355  }
1356 #endif
1357 
1358  /* Fix up any global config values that we can handle before replacing the config */
1359  if (cfg->general->use_even_ports && (cfg->general->start & 1)) {
1360  ++cfg->general->start;
1361  ast_log(LOG_NOTICE, "Odd numbered udptlstart specified but use_even_ports enabled. udptlstart is now %u\n", cfg->general->start);
1362  }
1363  if (cfg->general->start > cfg->general->end) {
1364  ast_log(LOG_WARNING, "Unreasonable values for UDPTL start/end ports; defaulting to %s-%s.\n", __stringify(DEFAULT_UDPTLSTART), __stringify(DEFAULT_UDPTLEND));
1366  cfg->general->end = DEFAULT_UDPTLEND;
1367  }
1368  if (cfg->general->use_even_ports && (cfg->general->end & 1)) {
1369  --cfg->general->end;
1370  ast_log(LOG_NOTICE, "Odd numbered udptlend specified but use_even_ports enabled. udptlend is now %u\n", cfg->general->end);
1371  }
1372 
1373  return 0;
1374 }
1375 
1376 static int reload_module(void)
1377 {
1378  __ast_udptl_reload(1);
1379 
1380  return 0;
1381 }
1382 
1383 /*!
1384  * \internal
1385  * \brief Clean up resources on Asterisk shutdown
1386  */
1387 static int unload_module(void)
1388 {
1389  ast_cli_unregister_multiple(cli_udptl, ARRAY_LEN(cli_udptl));
1390  ao2_t_global_obj_release(globals, "Unref udptl global container in shutdown");
1391  aco_info_destroy(&cfg_info);
1392 
1393  return 0;
1394 }
1395 
1396 static int load_module(void)
1397 {
1398  if (aco_info_init(&cfg_info)) {
1399  return AST_MODULE_LOAD_FAILURE;
1400  }
1401 
1402  aco_option_register(&cfg_info, "udptlstart", ACO_EXACT, general_options, __stringify(DEFAULT_UDPTLSTART),
1404  FLDSET(struct udptl_global_options, start), DEFAULT_UDPTLSTART, 1024, 65535);
1405 
1406  aco_option_register(&cfg_info, "udptlend", ACO_EXACT, general_options, __stringify(DEFAULT_UDPTLEND),
1408  FLDSET(struct udptl_global_options, end), DEFAULT_UDPTLEND, 1024, 65535);
1409 
1410  aco_option_register(&cfg_info, "udptlfecentries", ACO_EXACT, general_options, NULL,
1412  FLDSET(struct udptl_global_options, fecentries), 1, MAX_FEC_ENTRIES);
1413 
1414  aco_option_register(&cfg_info, "udptlfecspan", ACO_EXACT, general_options, NULL,
1416  FLDSET(struct udptl_global_options, fecspan), 1, MAX_FEC_SPAN);
1417 
1418  aco_option_register(&cfg_info, "udptlchecksums", ACO_EXACT, general_options, "yes",
1419  OPT_BOOL_T, 0, FLDSET(struct udptl_global_options, nochecksums));
1420 
1421  aco_option_register(&cfg_info, "use_even_ports", ACO_EXACT, general_options, "no",
1422  OPT_BOOL_T, 1, FLDSET(struct udptl_global_options, use_even_ports));
1423 
1424  aco_option_register_custom(&cfg_info, "t38faxudpec", ACO_EXACT, general_options, NULL, removed_options_handler, 0);
1425  aco_option_register_custom(&cfg_info, "t38faxmaxdatagram", ACO_EXACT, general_options, NULL, removed_options_handler, 0);
1426 
1427  __ast_udptl_reload(0);
1428 
1429  ast_cli_register_multiple(cli_udptl, ARRAY_LEN(cli_udptl));
1430 
1431  return AST_MODULE_LOAD_SUCCESS;
1432 }
1433 
1435  .support_level = AST_MODULE_SUPPORT_CORE,
1436  .load = load_module,
1437  .unload = unload_module,
1438  .reload = reload_module,
1439  .load_pri = AST_MODPRI_CORE,
1440  .requires = "extconfig",
1441 );
int fd
Definition: udptl.c:157
static void * udptl_snapshot_alloc(void)
Definition: udptl.c:1302
CONFIG_INFO_CORE("udptl", cfg_info, globals, udptl_snapshot_alloc,.files=ACO_FILES(&udptl_conf),.pre_apply_config=udptl_pre_apply_config,)
unsigned int fec_entries
Definition: udptl.c:152
#define AST_CLI_DEFINE(fn, txt,...)
Definition: cli.h:197
static AO2_GLOBAL_OBJ_STATIC(globals)
unsigned int cos
Definition: chan_iax2.c:352
ssize_t ast_sendto(int sockfd, const void *buf, size_t len, int flags, const struct ast_sockaddr *dest_addr)
Wrapper around sendto(2) that uses ast_sockaddr.
Definition: netsock2.c:614
int ast_udptl_setqos(struct ast_udptl *udptl, unsigned int tos, unsigned int cos)
Definition: udptl.c:1125
Asterisk locking-related definitions:
Asterisk main include file. File version handling, generic pbx functions.
static struct aco_file udptl_conf
Definition: udptl.c:248
static void udptl_config_destructor(void *obj)
Definition: udptl.c:1296
#define ARRAY_LEN(a)
Definition: isdn_lib.c:42
int nat
Definition: udptl.c:162
static struct ast_sched_context * sched
Definition: chan_ooh323.c:400
unsigned int ast_udptl_get_far_max_datagram(const struct ast_udptl *udptl)
Definition: udptl.c:1008
unsigned int error_correction_span
Definition: udptl.c:186
static int udptl_pre_apply_config(void)
Definition: udptl.c:1344
#define aco_option_register_custom(info, name, matchtype, types, default_val, handler, flags)
Register a config option.
int ast_udptl_fd(const struct ast_udptl *udptl)
Definition: udptl.c:730
unsigned int fecspan
Definition: udptl.c:224
int ast_cli_unregister_multiple(struct ast_cli_entry *e, int len)
Unregister multiple commands.
Definition: clicompat.c:30
int local_max_datagram
Definition: udptl.c:197
enum ast_t38_ec_modes ast_udptl_get_error_correction_scheme(const struct ast_udptl *udptl)
Definition: udptl.c:940
static char * handle_cli_udptl_set_debug(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
Definition: udptl.c:1215
static struct ast_sockaddr udptldebugaddr
Definition: udptl.c:131
static void __ast_udptl_reload(int reload)
Definition: udptl.c:1327
static void ast_sockaddr_copy(struct ast_sockaddr *dst, const struct ast_sockaddr *src)
Copies the data from one ast_sockaddr to another.
Definition: netsock2.h:171
char buf[BUFSIZE]
Definition: eagi_proxy.c:66
void ast_udptl_get_us(const struct ast_udptl *udptl, struct ast_sockaddr *us)
Definition: udptl.c:1140
ast_udptl_callback callback
Definition: udptl.c:171
static void calculate_local_max_datagram(struct ast_udptl *udptl)
Definition: udptl.c:831
descriptor for a cli entry.
Definition: cli.h:171
const int argc
Definition: cli.h:160
#define LOG_WARNING
Definition: logger.h:274
static int nat
Definition: chan_mgcp.c:168
#define ast_socket_nonblock(domain, type, protocol)
Create a non-blocking socket.
Definition: utils.h:1043
#define aco_option_register(info, name, matchtype, types, default_val, opt_type, flags,...)
Register a config option.
int * ioid
Definition: udptl.c:166
void ast_udptl_set_peer(struct ast_udptl *udptl, const struct ast_sockaddr *them)
Definition: udptl.c:1130
socklen_t len
Definition: netsock2.h:99
Structure for variables, used for configurations and for channel variables.
UDPTL support for T.38.
#define var
Definition: ast_expr2f.c:614
static int reload_module(void)
Definition: udptl.c:1376
#define AST_LIST_NEXT(elm, field)
Returns the next entry in the list after the given entry.
Definition: linkedlists.h:438
void ast_udptl_set_error_correction_scheme(struct ast_udptl *udptl, enum ast_t38_ec_modes ec)
Definition: udptl.c:945
#define AST_IO_IN
Definition: io.h:34
char * tag
Definition: udptl.c:170
Definition: sched.c:76
Definition: cli.h:152
#define ao2_t_global_obj_release(holder, tag)
Release the ao2 object held in the global holder.
Definition: astobj2.h:863
Structure for an UDPTL session.
Definition: udptl.c:156
int * ast_io_add(struct io_context *ioc, int fd, ast_io_cb callback, short events, void *data)
Adds an IO context.
Definition: io.c:162
static const struct adsi_event events[]
Definition: app_adsiprog.c:85
#define ast_cli_register_multiple(e, len)
Register multiple commands.
Definition: cli.h:265
enum aco_process_status aco_process_config(struct aco_info *info, int reload)
Process a config info via the options registered with an aco_info.
#define ao2_global_obj_ref(holder)
Definition: astobj2.h:925
#define DEFAULT_UDPTLSTART
Definition: udptl.c:127
#define ast_assert(a)
Definition: utils.h:695
#define ast_vasprintf(ret, fmt, ap)
A wrapper for vasprintf()
Definition: astmm.h:280
unsigned int error_correction_entries
Definition: udptl.c:181
#define NULL
Definition: resample.c:96
int ast_sockaddr_cmp(const struct ast_sockaddr *a, const struct ast_sockaddr *b)
Compares two ast_sockaddr structures.
Definition: netsock2.c:388
char * end
Definition: eagi_proxy.c:73
static int udptl_debug_test_addr(const struct ast_sockaddr *addr)
Definition: udptl.c:258
The representation of a single configuration file to be processed.
int value
Definition: syslog.c:37
void ast_cli(int fd, const char *fmt,...)
Definition: clicompat.c:6
struct ast_sockaddr us
Definition: udptl.c:164
enum aco_type_t type
Socket address structure.
Definition: netsock2.h:97
#define ACO_TYPES(...)
A helper macro to ensure that aco_info types always have a sentinel.
int ast_bind(int sockfd, const struct ast_sockaddr *addr)
Wrapper around bind(2) that uses struct ast_sockaddr.
Definition: netsock2.c:590
#define ast_verb(level,...)
Definition: logger.h:463
int ast_sockaddr_cmp_addr(const struct ast_sockaddr *a, const struct ast_sockaddr *b)
Compares the addresses of two ast_sockaddr structures.
Definition: netsock2.c:413
static struct aco_type * general_options[]
Definition: udptl.c:246
struct ast_frame_subclass subclass
Utility functions.
static void ast_sockaddr_setnull(struct ast_sockaddr *addr)
Sets address addr to null.
Definition: netsock2.h:140
unsigned int fecentries
Definition: udptl.c:223
uint8_t buf[LOCAL_FAX_MAX_DATAGRAM]
Definition: udptl.c:143
unsigned int tos
Definition: chan_iax2.c:351
static int decode_length(uint8_t *buf, unsigned int limit, unsigned int *len, unsigned int *pvalue)
Definition: udptl.c:274
static int encode_open_type(const struct ast_udptl *udptl, uint8_t *buf, unsigned int buflen, unsigned int *len, const uint8_t *data, unsigned int num_octets)
Definition: udptl.c:348
unsigned int fec_len[MAX_FEC_ENTRIES]
Definition: udptl.c:149
static int removed_options_handler(const struct aco_option *opt, struct ast_variable *var, void *obj)
Definition: udptl.c:1317
static int ast_sockaddr_isnull(const struct ast_sockaddr *addr)
Checks if the ast_sockaddr is null. "null" in this sense essentially means uninitialized, or having a 0 length.
Definition: netsock2.h:127
static unsigned int encode_length(uint8_t *buf, unsigned int *len, unsigned int value)
Definition: udptl.c:320
#define ast_sockaddr_port(addr)
Get the port number of a socket address.
Definition: netsock2.h:521
#define MIN(a, b)
Definition: utils.h:226
unsigned int lasteventseqn
Definition: udptl.c:161
#define ast_debug(level,...)
Log a DEBUG message.
Definition: logger.h:452
#define ast_log
Definition: astobj2.c:42
Handle unaligned data access.
#define __stringify(x)
Definition: asterisk.h:214
#define FLDSET(type,...)
Convert a struct and list of fields to an argument list of field offsets.
int aco_info_init(struct aco_info *info)
Initialize an aco_info structure.
General Asterisk PBX channel definitions.
#define AST_FRIENDLY_OFFSET
Offset into a frame&#39;s data buffer.
const char * src
void * aco_pending_config(struct aco_info *info)
Get pending config changes.
#define RAII_VAR(vartype, varname, initval, dtor)
Declare a variable that will call a destructor function when it goes out of scope.
Definition: utils.h:911
Type for default option handler for unsigned integers.
int far_max_datagram
Definition: udptl.c:191
const int fd
Definition: cli.h:159
ast_t38_ec_modes
Definition: udptl.h:37
struct ast_sched_context * sched
Definition: udptl.c:167
static struct io_context * io
Definition: chan_ooh323.c:401
int(* ast_udptl_callback)(struct ast_udptl *udptl, struct ast_frame *f, void *data)
Definition: udptl.h:49
udptl_fec_rx_buffer_t rx[UDPTL_BUF_MASK+1]
Definition: udptl.c:217
Access Control of various sorts.
Global IO variables are now in a struct in order to be made threadsafe.
Definition: io.c:71
#define LOCAL_FAX_MAX_DATAGRAM
Definition: udptl.c:133
Asterisk internal frame definitions.
#define ao2_ref(o, delta)
Definition: astobj2.h:464
long int ast_random(void)
Definition: main/utils.c:2064
#define TRUE
Definition: udptl.c:122
unsigned int end
Definition: udptl.c:222
struct ast_sockaddr them
Definition: udptl.c:165
unsigned int tx_seq_no
Definition: udptl.c:213
void ast_udptl_set_local_max_ifp(struct ast_udptl *udptl, unsigned int max_ifp)
Definition: udptl.c:973
static struct console_pvt globals
static int decode_open_type(uint8_t *buf, unsigned int limit, unsigned int *len, const uint8_t **p_object, unsigned int *p_num_octets)
Definition: udptl.c:300
#define LOG_TAG(u)
Definition: udptl.c:125
unsigned int nochecksums
Definition: udptl.c:225
struct ast_frame * ast_udptl_read(struct ast_udptl *udptl)
Definition: udptl.c:762
Network socket handling.
uint8_t buf[LOCAL_FAX_MAX_DATAGRAM]
Definition: udptl.c:148
Their was an error and no changes were applied.
const char *const * argv
Definition: cli.h:161
static int udptlread(int *id, int fd, short events, void *cbdata)
Definition: udptl.c:750
Configuration option-handling.
static int unload_module(void)
Definition: udptl.c:1387
#define LOG_ERROR
Definition: logger.h:285
struct io_context * io
Definition: udptl.c:168
void ast_udptl_stop(struct ast_udptl *udptl)
Definition: udptl.c:1145
#define CLI_SHOWUSAGE
Definition: cli.h:45
#define ast_sockaddr_set_port(addr, port)
Sets the port number of a socket address.
Definition: netsock2.h:537
void ast_udptl_set_tag(struct ast_udptl *udptl, const char *format,...)
Associates a character string &#39;tag&#39; with a UDPTL session.
Definition: udptl.c:1112
void aco_info_destroy(struct aco_info *info)
Destroy an initialized aco_info struct.
void ast_udptl_set_callback(struct ast_udptl *udptl, ast_udptl_callback callback)
Definition: udptl.c:740
Type for default option handler for bools (ast_true/ast_false)
int ast_set_qos(int sockfd, int tos, int cos, const char *desc)
Set type of service.
Definition: netsock2.c:621
int errno
unsigned int rx_seq_no
Definition: udptl.c:214
static char * ast_sockaddr_stringify(const struct ast_sockaddr *addr)
Wrapper around ast_sockaddr_stringify_fmt() with default format.
Definition: netsock2.h:260
unsigned int ast_udptl_get_local_max_datagram(struct ast_udptl *udptl)
retrieves local_max_datagram.
Definition: udptl.c:984
ssize_t ast_recvfrom(int sockfd, void *buf, size_t len, int flags, struct ast_sockaddr *src_addr)
Wrapper around recvfrom(2) that uses struct ast_sockaddr.
Definition: netsock2.c:606
#define ao2_alloc(data_size, destructor_fn)
Definition: astobj2.h:411
#define LOG_NOTICE
Definition: logger.h:263
static int load_module(void)
Definition: udptl.c:1396
void ast_udptl_get_peer(const struct ast_udptl *udptl, struct ast_sockaddr *them)
Definition: udptl.c:1135
uint8_t fec[MAX_FEC_ENTRIES][LOCAL_FAX_MAX_DATAGRAM]
Definition: udptl.c:150
struct ast_udptl * ast_udptl_new_with_bindaddr(struct ast_sched_context *sched, struct io_context *io, int callbackmode, struct ast_sockaddr *addr)
Definition: udptl.c:1028
void ast_udptl_set_data(struct ast_udptl *udptl, void *data)
Definition: udptl.c:735
#define CLI_FAILURE
Definition: cli.h:46
#define ast_free(a)
Definition: astmm.h:182
char * command
Definition: cli.h:186
#define ast_calloc(num, len)
A wrapper for calloc()
Definition: astmm.h:204
void ast_udptl_set_far_max_datagram(struct ast_udptl *udptl, unsigned int max_datagram)
sets far max datagram size. If max_datagram is = 0, the far max datagram size is set to a default val...
Definition: udptl.c:997
unsigned int use_even_ports
Definition: udptl.c:226
static int reload(void)
Definition: cdr_mysql.c:741
int aco_set_defaults(struct aco_type *type, const char *category, void *obj)
Set all default options of obj.
Module could not be loaded properly.
Definition: module.h:102
int far_max_ifp
Definition: udptl.c:205
void ast_udptl_destroy(struct ast_udptl *udptl)
Definition: udptl.c:1150
void ast_udptl_setnat(struct ast_udptl *udptl, int nat)
Definition: udptl.c:745
static int udptl_build_packet(struct ast_udptl *s, uint8_t *buf, unsigned int buflen, uint8_t *ifp, unsigned int ifp_len)
Definition: udptl.c:621
struct ast_frame f[16]
Definition: udptl.c:159
int ast_io_remove(struct io_context *ioc, int *id)
Removes an IO context.
Definition: io.c:245
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS|AST_MODFLAG_LOAD_ORDER, "HTTP Phone Provisioning",.support_level=AST_MODULE_SUPPORT_EXTENDED,.load=load_module,.unload=unload_module,.reload=reload,.load_pri=AST_MODPRI_CHANNEL_DEPEND,.requires="http",)
const char * usage
Definition: cli.h:177
struct ast_frame ast_null_frame
Definition: main/frame.c:79
#define CLI_SUCCESS
Definition: cli.h:44
#define ao2_global_obj_replace_unref(holder, obj)
Definition: astobj2.h:908
#define ACO_FILES(...)
static volatile unsigned int seq
Definition: app_sms.c:120
int flags
Definition: udptl.c:163
#define ao2_cleanup(obj)
Definition: astobj2.h:1958
Standard Command Line Interface.
Type information about a category-level configurable object.
#define DEFAULT_UDPTLEND
Definition: udptl.c:128
const char * filename
unsigned char rawdata[8192+AST_FRIENDLY_OFFSET]
Definition: udptl.c:160
int local_max_ifp
Definition: udptl.c:211
#define AST_MODEM_T38
Data structure associated with a single frame of data.
unsigned int fec_span
Definition: udptl.c:151
#define MAX_FEC_SPAN
Definition: udptl.c:137
Definition: search.h:40
union ast_frame::@263 data
enum ast_frame_type frametype
#define MAX_FEC_ENTRIES
Definition: udptl.c:136
#define AST_CLI_YESNO(x)
Return Yes or No depending on the argument.
Definition: cli.h:71
static void calculate_far_max_ifp(struct ast_udptl *udptl)
Definition: udptl.c:872
#define FAX_MAX_DATAGRAM_LIMIT
Definition: udptl.c:135
static char * handle_cli_show_config(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
Definition: udptl.c:1260
int ast_udptl_write(struct ast_udptl *s, struct ast_frame *f)
Definition: udptl.c:1161
udptl_fec_tx_buffer_t tx[UDPTL_BUF_MASK+1]
Definition: udptl.c:216
struct udptl_global_options * general
Definition: udptl.c:232
static struct ast_cli_entry cli_udptl[]
Definition: udptl.c:1291
#define ASTERISK_GPL_KEY
The text the key() function should return.
Definition: module.h:46
Asterisk module definitions.
char resp
Definition: udptl.c:158
static snd_pcm_format_t format
Definition: chan_alsa.c:102
#define UDPTL_BUF_MASK
Definition: udptl.c:139
int ast_sockaddr_is_ipv6(const struct ast_sockaddr *addr)
Determine if this is an IPv6 address.
Definition: netsock2.c:524
static int udptl_rx_packet(struct ast_udptl *s, uint8_t *buf, unsigned int len)
Definition: udptl.c:381
enum ast_t38_ec_modes error_correction_scheme
Definition: udptl.c:176
static struct aco_type general_option
Definition: udptl.c:238
void * data
Definition: udptl.c:169
#define DEFAULT_FAX_MAX_DATAGRAM
Definition: udptl.c:134
unsigned int ast_udptl_get_far_max_ifp(struct ast_udptl *udptl)
retrieves far max ifp
Definition: udptl.c:1016
int ast_sockaddr_resolve(struct ast_sockaddr **addrs, const char *str, int flags, int family)
Parses a string with an IPv4 or IPv6 address and place results into an array.
Definition: netsock2.c:280
static int udptldebug
Definition: udptl.c:130
static struct test_val a
unsigned int start
Definition: udptl.c:221