udptl.c File Reference

01312 {
01313    struct ast_config *cfg;
01314    const char *s;
01315    struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };
01316 
01317    cfg = ast_config_load2("udptl.conf", "udptl", config_flags);
01318    if (cfg == CONFIG_STATUS_FILEMISSING || cfg == CONFIG_STATUS_FILEUNCHANGED || cfg == CONFIG_STATUS_FILEINVALID) {
01319       return;
01320    }
01321 
01322    udptlstart = DEFAULT_UDPTLSTART;
01323    udptlend = DEFAULT_UDPTLEND;
01324    udptlfecentries = 0;
01325    udptlfecspan = 0;
01326    use_even_ports = 0;
01327 
01328    if (cfg) {
01329       if ((s = ast_variable_retrieve(cfg, "general", "udptlstart"))) {
01330          udptlstart = atoi(s);
01331          if (udptlstart < 1024) {
01332             ast_log(LOG_WARNING, "Ports under 1024 are not allowed for T.38.\n");
01333             udptlstart = 1024;
01334          }
01335          if (udptlstart > 65535) {
01336             ast_log(LOG_WARNING, "Ports over 65535 are invalid.\n");
01337             udptlstart = 65535;
01338          }
01339       }
01340       if ((s = ast_variable_retrieve(cfg, "general", "udptlend"))) {
01341          udptlend = atoi(s);
01342          if (udptlend < 1024) {
01343             ast_log(LOG_WARNING, "Ports under 1024 are not allowed for T.38.\n");
01344             udptlend = 1024;
01345          }
01346          if (udptlend > 65535) {
01347             ast_log(LOG_WARNING, "Ports over 65535 are invalid.\n");
01348             udptlend = 65535;
01349          }
01350       }
01351       if ((s = ast_variable_retrieve(cfg, "general", "udptlchecksums"))) {
01352 #ifdef SO_NO_CHECK
01353          if (ast_false(s))
01354             nochecksums = 1;
01355          else
01356             nochecksums = 0;
01357 #else
01358          if (ast_false(s))
01359             ast_log(LOG_WARNING, "Disabling UDPTL checksums is not supported on this operating system!\n");
01360 #endif
01361       }
01362       if ((s = ast_variable_retrieve(cfg, "general", "T38FaxUdpEC"))) {
01363          ast_log(LOG_WARNING, "T38FaxUdpEC in udptl.conf is no longer supported; use the t38pt_udptl configuration option in sip.conf instead.\n");
01364       }
01365       if ((s = ast_variable_retrieve(cfg, "general", "T38FaxMaxDatagram"))) {
01366          ast_log(LOG_WARNING, "T38FaxMaxDatagram in udptl.conf is no longer supported; value is now supplied by T.38 applications.\n");
01367       }
01368       if ((s = ast_variable_retrieve(cfg, "general", "UDPTLFECEntries"))) {
01369          udptlfecentries = atoi(s);
01370          if (udptlfecentries < 1) {
01371             ast_log(LOG_WARNING, "Too small UDPTLFECEntries value.  Defaulting to 1.\n");
01372             udptlfecentries = 1;
01373          }
01374          if (udptlfecentries > MAX_FEC_ENTRIES) {
01375             ast_log(LOG_WARNING, "Too large UDPTLFECEntries value.  Defaulting to %d.\n", MAX_FEC_ENTRIES);
01376             udptlfecentries = MAX_FEC_ENTRIES;
01377          }
01378       }
01379       if ((s = ast_variable_retrieve(cfg, "general", "UDPTLFECSpan"))) {
01380          udptlfecspan = atoi(s);
01381          if (udptlfecspan < 1) {
01382             ast_log(LOG_WARNING, "Too small UDPTLFECSpan value.  Defaulting to 1.\n");
01383             udptlfecspan = 1;
01384          }
01385          if (udptlfecspan > MAX_FEC_SPAN) {
01386             ast_log(LOG_WARNING, "Too large UDPTLFECSpan value.  Defaulting to %d.\n", MAX_FEC_SPAN);
01387             udptlfecspan = MAX_FEC_SPAN;
01388          }
01389       }
01390       if ((s = ast_variable_retrieve(cfg, "general", "use_even_ports"))) {
01391          use_even_ports = ast_true(s);
01392       }
01393       ast_config_destroy(cfg);
01394    }
01395    if (use_even_ports && (udptlstart & 1)) {
01396       ++udptlstart;
01397       ast_log(LOG_NOTICE, "Odd numbered udptlstart specified but use_even_ports enabled. udptlstart is now %d\n", udptlstart);
01398    }
01399    if (udptlstart > udptlend) {
01400       ast_log(LOG_WARNING, "Unreasonable values for UDPTL start/end ports; defaulting to %d-%d.\n", DEFAULT_UDPTLSTART, DEFAULT_UDPTLEND);
01401       udptlstart = DEFAULT_UDPTLSTART;
01402       udptlend = DEFAULT_UDPTLEND;
01403    }
01404    if (use_even_ports && (udptlend & 1)) {
01405       --udptlend;
01406       ast_log(LOG_NOTICE, "Odd numbered udptlend specified but use_even_ports enabled. udptlend is now %d\n", udptlend);
01407    }
01408    ast_verb(2, "UDPTL allocating from port range %d -> %d\n", udptlstart, udptlend);
01409 }

static void __fini_protos ( void ) [static]

Definition at line 183 of file udptl.c.

00186 {

static void __init_protos ( void ) [static]

Definition at line 183 of file udptl.c.

00186 {

int ast_udptl_bridge	(	struct ast_channel *	c0,
		struct ast_channel *	c1,
		int	flags,
		struct ast_frame **	fo,
		struct ast_channel **	rc
	)

Definition at line 1136 of file udptl.c.

References ast_channel_lock, ast_channel_name(), ast_channel_trylock, ast_channel_unlock, ast_check_hangup(), ast_debug, AST_FRAME_MODEM, ast_frfree, ast_log(), ast_read(), ast_sockaddr_cmp(), ast_sockaddr_copy(), ast_sockaddr_stringify(), ast_udptl_get_peer(), ast_waitfor_n(), ast_write(), f, ast_frame::frametype, get_proto(), ast_udptl_protocol::get_udptl_info, LOG_WARNING, ast_channel::masq, ast_channel::masqr, ast_udptl_protocol::set_udptl_peer, and ast_channel::tech_pvt.

01137 {
01138    struct ast_frame *f;
01139    struct ast_channel *who;
01140    struct ast_channel *cs[3];
01141    struct ast_udptl *p0;
01142    struct ast_udptl *p1;
01143    struct ast_udptl_protocol *pr0;
01144    struct ast_udptl_protocol *pr1;
01145    struct ast_sockaddr ac0;
01146    struct ast_sockaddr ac1;
01147    struct ast_sockaddr t0;
01148    struct ast_sockaddr t1;
01149    void *pvt0;
01150    void *pvt1;
01151    int to;
01152    
01153    ast_channel_lock(c0);
01154    while (ast_channel_trylock(c1)) {
01155       ast_channel_unlock(c0);
01156       usleep(1);
01157       ast_channel_lock(c0);
01158    }
01159    pr0 = get_proto(c0);
01160    pr1 = get_proto(c1);
01161    if (!pr0) {
01162       ast_log(LOG_WARNING, "Can't find native functions for channel '%s'\n", ast_channel_name(c0));
01163       ast_channel_unlock(c0);
01164       ast_channel_unlock(c1);
01165       return -1;
01166    }
01167    if (!pr1) {
01168       ast_log(LOG_WARNING, "Can't find native functions for channel '%s'\n", ast_channel_name(c1));
01169       ast_channel_unlock(c0);
01170       ast_channel_unlock(c1);
01171       return -1;
01172    }
01173    pvt0 = c0->tech_pvt;
01174    pvt1 = c1->tech_pvt;
01175    p0 = pr0->get_udptl_info(c0);
01176    p1 = pr1->get_udptl_info(c1);
01177    if (!p0 || !p1) {
01178       /* Somebody doesn't want to play... */
01179       ast_channel_unlock(c0);
01180       ast_channel_unlock(c1);
01181       return -2;
01182    }
01183    if (pr0->set_udptl_peer(c0, p1)) {
01184       ast_log(LOG_WARNING, "Channel '%s' failed to talk to '%s'\n", ast_channel_name(c0), ast_channel_name(c1));
01185       memset(&ac1, 0, sizeof(ac1));
01186    } else {
01187       /* Store UDPTL peer */
01188       ast_udptl_get_peer(p1, &ac1);
01189    }
01190    if (pr1->set_udptl_peer(c1, p0)) {
01191       ast_log(LOG_WARNING, "Channel '%s' failed to talk back to '%s'\n", ast_channel_name(c1), ast_channel_name(c0));
01192       memset(&ac0, 0, sizeof(ac0));
01193    } else {
01194       /* Store UDPTL peer */
01195       ast_udptl_get_peer(p0, &ac0);
01196    }
01197    ast_channel_unlock(c0);
01198    ast_channel_unlock(c1);
01199    cs[0] = c0;
01200    cs[1] = c1;
01201    cs[2] = NULL;
01202    for (;;) {
01203       if ((c0->tech_pvt != pvt0) ||
01204          (c1->tech_pvt != pvt1) ||
01205          (c0->masq || c0->masqr || c1->masq || c1->masqr)) {
01206             ast_debug(1, "Oooh, something is weird, backing out\n");
01207             /* Tell it to try again later */
01208             return -3;
01209       }
01210       to = -1;
01211       ast_udptl_get_peer(p1, &t1);
01212       ast_udptl_get_peer(p0, &t0);
01213       if (ast_sockaddr_cmp(&t1, &ac1)) {
01214          ast_debug(1, "Oooh, '%s' changed end address to %s\n", 
01215             ast_channel_name(c1), ast_sockaddr_stringify(&t1));
01216          ast_debug(1, "Oooh, '%s' was %s\n", 
01217             ast_channel_name(c1), ast_sockaddr_stringify(&ac1));
01218          ast_sockaddr_copy(&ac1, &t1);
01219       }
01220       if (ast_sockaddr_cmp(&t0, &ac0)) {
01221          ast_debug(1, "Oooh, '%s' changed end address to %s\n", 
01222             ast_channel_name(c0), ast_sockaddr_stringify(&t0));
01223          ast_debug(1, "Oooh, '%s' was %s\n", 
01224             ast_channel_name(c0), ast_sockaddr_stringify(&ac0));
01225          ast_sockaddr_copy(&ac0, &t0);
01226       }
01227       who = ast_waitfor_n(cs, 2, &to);
01228       if (!who) {
01229          ast_debug(1, "Ooh, empty read...\n");
01230          /* check for hangup / whentohangup */
01231          if (ast_check_hangup(c0) || ast_check_hangup(c1))
01232             break;
01233          continue;
01234       }
01235       f = ast_read(who);
01236       if (!f) {
01237          *fo = f;
01238          *rc = who;
01239          ast_debug(1, "Oooh, got a %s\n", f ? "digit" : "hangup");
01240          /* That's all we needed */
01241          return 0;
01242       } else {
01243          if (f->frametype == AST_FRAME_MODEM) {
01244             /* Forward T.38 frames if they happen upon us */
01245             if (who == c0) {
01246                ast_write(c1, f);
01247             } else if (who == c1) {
01248                ast_write(c0, f);
01249             }
01250          }
01251          ast_frfree(f);
01252       }
01253       /* Swap priority. Not that it's a big deal at this point */
01254       cs[2] = cs[0];
01255       cs[0] = cs[1];
01256       cs[1] = cs[2];
01257    }
01258    return -1;
01259 }

void ast_udptl_destroy ( struct ast_udptl * udptl )

Definition at line 1033 of file udptl.c.

References ast_free, ast_io_remove(), ast_udptl::fd, ast_udptl::io, ast_udptl::ioid, and ast_udptl::tag.

Referenced by __sip_destroy().

01034 {
01035    if (udptl->ioid)
01036       ast_io_remove(udptl->io, udptl->ioid);
01037    if (udptl->fd > -1)
01038       close(udptl->fd);
01039    if (udptl->tag)
01040       ast_free(udptl->tag);
01041    ast_free(udptl);
01042 }

int ast_udptl_fd ( const struct ast_udptl * udptl )

Definition at line 632 of file udptl.c.

References ast_udptl::fd.

Referenced by __oh323_new(), initialize_udptl(), and sip_new().

00633 {
00634    return udptl->fd;
00635 }

enum ast_t38_ec_modes ast_udptl_get_error_correction_scheme ( const struct ast_udptl * udptl )

Definition at line 830 of file udptl.c.

References ast_udptl::error_correction_scheme.

Referenced by add_sdp().

00831 {
00832    return udptl->error_correction_scheme;
00833 }

unsigned int ast_udptl_get_far_max_datagram ( const struct ast_udptl * udptl )

Definition at line 898 of file udptl.c.

References ast_udptl::far_max_datagram.

Referenced by process_sdp().

00899 {
00900    if (udptl->far_max_datagram < 0) {
00901       return 0;
00902    }
00903    return udptl->far_max_datagram;
00904 }

unsigned int ast_udptl_get_far_max_ifp ( struct ast_udptl * udptl )

retrieves far max ifp

Return values:

	positive	value representing max ifp size
	0	if no value is present

Definition at line 906 of file udptl.c.

References calculate_far_max_ifp(), and ast_udptl::far_max_ifp.

Referenced by change_t38_state(), and interpret_t38_parameters().

00907 {
00908    if (udptl->far_max_ifp == -1) {
00909       calculate_far_max_ifp(udptl);
00910    }
00911 
00912    if (udptl->far_max_ifp < 0) {
00913       return 0;
00914    }
00915    return udptl->far_max_ifp;
00916 }

unsigned int ast_udptl_get_local_max_datagram ( struct ast_udptl * udptl )

retrieves local_max_datagram.

Return values:

	positive	value representing max datagram size.
	0	if no value is present

Definition at line 874 of file udptl.c.

References calculate_local_max_datagram(), and ast_udptl::local_max_datagram.

Referenced by add_sdp().

00875 {
00876    if (udptl->local_max_datagram == -1) {
00877       calculate_local_max_datagram(udptl);
00878    }
00879 
00880    /* this function expects a unsigned value in return. */
00881    if (udptl->local_max_datagram < 0) {
00882       return 0;
00883    }
00884    return udptl->local_max_datagram;
00885 }

void ast_udptl_get_peer	(	const struct ast_udptl *	udptl,
		struct ast_sockaddr *	them
	)

Definition at line 1018 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::them.

Referenced by ast_udptl_bridge(), and sip_set_udptl_peer().

01019 {
01020    ast_sockaddr_copy(them, &udptl->them);
01021 }

void ast_udptl_get_us	(	const struct ast_udptl *	udptl,
		struct ast_sockaddr *	us
	)

Definition at line 1023 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::us.

Referenced by add_sdp().

01024 {
01025    ast_sockaddr_copy(us, &udptl->us);
01026 }

void ast_udptl_init ( void )

Definition at line 1417 of file udptl.c.

References __ast_udptl_reload(), ARRAY_LEN, and ast_cli_register_multiple().

Referenced by main().

01418 {
01419    ast_cli_register_multiple(cli_udptl, ARRAY_LEN(cli_udptl));
01420    __ast_udptl_reload(0);
01421 }

struct ast_udptl* ast_udptl_new_with_bindaddr	(	struct ast_sched_context *	sched,
		struct io_context *	io,
		int	callbackmode,
		struct ast_sockaddr *	addr
	)			`[read]`

Definition at line 918 of file udptl.c.

References ast_bind(), ast_calloc, ast_free, ast_io_add(), AST_IO_IN, ast_log(), ast_random(), ast_sockaddr_copy(), ast_sockaddr_is_ipv6(), ast_sockaddr_set_port, udptl_fec_tx_buffer_t::buf_len, udptl_fec_rx_buffer_t::buf_len, errno, ast_udptl::error_correction_entries, ast_udptl::error_correction_span, ast_udptl::far_max_datagram, ast_udptl::far_max_ifp, ast_udptl::fd, ast_udptl::flags, ast_udptl::io, ast_udptl::ioid, ast_udptl::local_max_datagram, ast_udptl::local_max_ifp, LOG_WARNING, ast_udptl::rx, ast_udptl::sched, ast_udptl::tx, UDPTL_BUF_MASK, udptlread(), and ast_udptl::us.

Referenced by initialize_udptl().

00919 {
00920    struct ast_udptl *udptl;
00921    int x;
00922    int startplace;
00923    int i;
00924    long int flags;
00925 
00926    if (!(udptl = ast_calloc(1, sizeof(*udptl))))
00927       return NULL;
00928 
00929    udptl->error_correction_span = udptlfecspan;
00930    udptl->error_correction_entries = udptlfecentries;
00931    
00932    udptl->far_max_datagram = -1;
00933    udptl->far_max_ifp = -1;
00934    udptl->local_max_ifp = -1;
00935    udptl->local_max_datagram = -1;
00936 
00937    for (i = 0; i <= UDPTL_BUF_MASK; i++) {
00938       udptl->rx[i].buf_len = -1;
00939       udptl->tx[i].buf_len = -1;
00940    }
00941 
00942    if ((udptl->fd = socket(ast_sockaddr_is_ipv6(addr) ?
00943                AF_INET6 : AF_INET, SOCK_DGRAM, 0)) < 0) {
00944       ast_free(udptl);
00945       ast_log(LOG_WARNING, "Unable to allocate socket: %s\n", strerror(errno));
00946       return NULL;
00947    }
00948    flags = fcntl(udptl->fd, F_GETFL);
00949    fcntl(udptl->fd, F_SETFL, flags | O_NONBLOCK);
00950 #ifdef SO_NO_CHECK
00951    if (nochecksums)
00952       setsockopt(udptl->fd, SOL_SOCKET, SO_NO_CHECK, &nochecksums, sizeof(nochecksums));
00953 #endif
00954    /* Find us a place */
00955    x = (udptlstart == udptlend) ? udptlstart : (ast_random() % (udptlend - udptlstart)) + udptlstart;
00956    if (use_even_ports && (x & 1)) {
00957       ++x;
00958    }
00959    startplace = x;
00960    for (;;) {
00961       ast_sockaddr_copy(&udptl->us, addr);
00962       ast_sockaddr_set_port(&udptl->us, x);
00963       if (ast_bind(udptl->fd, &udptl->us) == 0) {
00964          break;
00965       }
00966       if (errno != EADDRINUSE) {
00967          ast_log(LOG_WARNING, "Unexpected bind error: %s\n", strerror(errno));
00968          close(udptl->fd);
00969          ast_free(udptl);
00970          return NULL;
00971       }
00972       if (use_even_ports) {
00973          x += 2;
00974       } else {
00975          ++x;
00976       }
00977       if (x > udptlend)
00978          x = udptlstart;
00979       if (x == startplace) {
00980          ast_log(LOG_WARNING, "No UDPTL ports remaining\n");
00981          close(udptl->fd);
00982          ast_free(udptl);
00983          return NULL;
00984       }
00985    }
00986    if (io && sched && callbackmode) {
00987       /* Operate this one in a callback mode */
00988       udptl->sched = sched;
00989       udptl->io = io;
00990       udptl->ioid = ast_io_add(udptl->io, udptl->fd, udptlread, AST_IO_IN, udptl);
00991    }
00992    return udptl;
00993 }

int ast_udptl_proto_register ( struct ast_udptl_protocol * proto )

Definition at line 1105 of file udptl.c.

References ast_log(), AST_RWLIST_INSERT_TAIL, AST_RWLIST_TRAVERSE, AST_RWLIST_UNLOCK, AST_RWLIST_WRLOCK, ast_udptl_protocol::list, LOG_WARNING, and ast_udptl_protocol::type.

Referenced by load_module().

01106 {
01107    struct ast_udptl_protocol *cur;
01108 
01109    AST_RWLIST_WRLOCK(&protos);
01110    AST_RWLIST_TRAVERSE(&protos, cur, list) {
01111       if (cur->type == proto->type) {
01112          ast_log(LOG_WARNING, "Tried to register same protocol '%s' twice\n", cur->type);
01113          AST_RWLIST_UNLOCK(&protos);
01114          return -1;
01115       }
01116    }
01117    AST_RWLIST_INSERT_TAIL(&protos, proto, list);
01118    AST_RWLIST_UNLOCK(&protos);
01119    return 0;
01120 }

void ast_udptl_proto_unregister ( struct ast_udptl_protocol * proto )

Definition at line 1098 of file udptl.c.

References AST_RWLIST_REMOVE, AST_RWLIST_UNLOCK, and AST_RWLIST_WRLOCK.

Referenced by unload_module().

01099 {
01100    AST_RWLIST_WRLOCK(&protos);
01101    AST_RWLIST_REMOVE(&protos, proto, list);
01102    AST_RWLIST_UNLOCK(&protos);
01103 }

struct ast_frame* ast_udptl_read ( struct ast_udptl * udptl ) [read]

Definition at line 664 of file udptl.c.

References ast_assert, ast_debug, AST_FRIENDLY_OFFSET, ast_log(), ast_null_frame, ast_recvfrom(), ast_sockaddr_cmp(), ast_sockaddr_copy(), ast_sockaddr_isnull(), ast_sockaddr_stringify(), ast_verb, errno, ast_udptl::f, ast_udptl::fd, LOG_TAG, LOG_WARNING, ast_udptl::nat, ast_udptl::rawdata, ast_udptl::them, udptl_debug_test_addr(), and udptl_rx_packet().

Referenced by sip_rtp_read(), skinny_rtp_read(), and udptlread().

00665 {
00666    int res;
00667    struct ast_sockaddr addr;
00668    uint8_t *buf;
00669 
00670    buf = udptl->rawdata + AST_FRIENDLY_OFFSET;
00671 
00672    /* Cache where the header will go */
00673    res = ast_recvfrom(udptl->fd,
00674          buf,
00675          sizeof(udptl->rawdata) - AST_FRIENDLY_OFFSET,
00676          0,
00677          &addr);
00678    if (res < 0) {
00679       if (errno != EAGAIN)
00680          ast_log(LOG_WARNING, "UDPTL (%s): read error: %s\n",
00681             LOG_TAG(udptl), strerror(errno));
00682       ast_assert(errno != EBADF);
00683       return &ast_null_frame;
00684    }
00685 
00686    /* Ignore if the other side hasn't been given an address yet. */
00687    if (ast_sockaddr_isnull(&udptl->them)) {
00688       return &ast_null_frame;
00689    }
00690 
00691    if (udptl->nat) {
00692       /* Send to whoever sent to us */
00693       if (ast_sockaddr_cmp(&udptl->them, &addr)) {
00694          ast_sockaddr_copy(&udptl->them, &addr);
00695          ast_debug(1, "UDPTL (%s): NAT, Using address %s\n",
00696               LOG_TAG(udptl), ast_sockaddr_stringify(&udptl->them));
00697       }
00698    }
00699 
00700    if (udptl_debug_test_addr(&addr)) {
00701       int seq_no;
00702 
00703       /* Decode sequence number just for verbose message. */
00704       if (res < 2) {
00705          /* Short packet. */
00706          seq_no = -1;
00707       } else {
00708          seq_no = (buf[0] << 8) | buf[1];
00709       }
00710 
00711       ast_verb(1, "UDPTL (%s): packet from %s (seq %d, len %d)\n",
00712          LOG_TAG(udptl), ast_sockaddr_stringify(&addr), seq_no, res);
00713    }
00714    if (udptl_rx_packet(udptl, buf, res) < 1) {
00715       return &ast_null_frame;
00716    }
00717 
00718    return &udptl->f[0];
00719 }

int ast_udptl_reload ( void )

Version:: 1.6.1 return changed to int

Definition at line 1411 of file udptl.c.

References __ast_udptl_reload().

01412 {
01413    __ast_udptl_reload(1);
01414    return 0;
01415 }

void ast_udptl_set_callback	(	struct ast_udptl *	udptl,
		ast_udptl_callback	callback
	)

Definition at line 642 of file udptl.c.

References ast_udptl::callback.

00643 {
00644    udptl->callback = callback;
00645 }

void ast_udptl_set_data	(	struct ast_udptl *	udptl,
		void *	data
	)

Definition at line 637 of file udptl.c.

References ast_udptl::data.

00638 {
00639    udptl->data = data;
00640 }

void ast_udptl_set_error_correction_scheme	(	struct ast_udptl *	udptl,
		enum ast_t38_ec_modes	ec
	)

Definition at line 835 of file udptl.c.

References ast_udptl::error_correction_entries, ast_udptl::error_correction_scheme, ast_udptl::error_correction_span, ast_udptl::far_max_ifp, ast_udptl::local_max_datagram, UDPTL_ERROR_CORRECTION_FEC, and UDPTL_ERROR_CORRECTION_REDUNDANCY.

Referenced by process_sdp(), process_sdp_a_image(), and set_t38_capabilities().

00836 {
00837    udptl->error_correction_scheme = ec;
00838    switch (ec) {
00839    case UDPTL_ERROR_CORRECTION_FEC:
00840       udptl->error_correction_scheme = UDPTL_ERROR_CORRECTION_FEC;
00841       if (udptl->error_correction_entries == 0) {
00842          udptl->error_correction_entries = 3;
00843       }
00844       if (udptl->error_correction_span == 0) {
00845          udptl->error_correction_span = 3;
00846       }
00847       break;
00848    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00849       udptl->error_correction_scheme = UDPTL_ERROR_CORRECTION_REDUNDANCY;
00850       if (udptl->error_correction_entries == 0) {
00851          udptl->error_correction_entries = 3;
00852       }
00853       break;
00854    default:
00855       /* nothing to do */
00856       break;
00857    };
00858    /* reset calculated values so they'll be computed again */
00859    udptl->local_max_datagram = -1;
00860    udptl->far_max_ifp = -1;
00861 }

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 value.

Definition at line 887 of file udptl.c.

References DEFAULT_FAX_MAX_DATAGRAM, ast_udptl::far_max_datagram, ast_udptl::far_max_ifp, and FAX_MAX_DATAGRAM_LIMIT.

Referenced by process_sdp(), and process_sdp_a_image().

00888 {
00889    if (!max_datagram || (max_datagram > FAX_MAX_DATAGRAM_LIMIT)) {
00890       udptl->far_max_datagram = DEFAULT_FAX_MAX_DATAGRAM;
00891    } else {
00892       udptl->far_max_datagram = max_datagram;
00893    }
00894    /* reset calculated values so they'll be computed again */
00895    udptl->far_max_ifp = -1;
00896 }

void ast_udptl_set_local_max_ifp	(	struct ast_udptl *	udptl,
		unsigned int	max_ifp
	)

Definition at line 863 of file udptl.c.

References ast_udptl::local_max_datagram, and ast_udptl::local_max_ifp.

Referenced by interpret_t38_parameters().

00864 {
00865    /* make sure max_ifp is a positive value since a cast will take place when
00866     * when setting local_max_ifp */
00867    if ((signed int) max_ifp > 0) {
00868       udptl->local_max_ifp = max_ifp;
00869       /* reset calculated values so they'll be computed again */
00870       udptl->local_max_datagram = -1;
00871    }
00872 }

void ast_udptl_set_peer	(	struct ast_udptl *	udptl,
		const struct ast_sockaddr *	them
	)

Definition at line 1013 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::them.

Referenced by process_sdp().

01014 {
01015    ast_sockaddr_copy(&udptl->them, them);
01016 }

void ast_udptl_set_tag	(	struct ast_udptl *	udptl,
		const char *	format,
			...
	)

Associates a character string 'tag' with a UDPTL session.

Parameters:

	udptl	The UDPTL session.
	format	printf-style format string used to construct the tag

This function formats a tag for the specified UDPTL session, so that any log messages generated by the UDPTL stack related to that session will include the tag and the reader of the messages will be able to identify which endpoint caused them to be generated.

Return values:

none

Definition at line 995 of file udptl.c.

References ast_free, ast_vasprintf, and ast_udptl::tag.

Referenced by change_t38_state().

00996 {
00997    va_list ap;
00998 
00999    ast_free(udptl->tag);
01000    udptl->tag = NULL;
01001    va_start(ap, format);
01002    if (ast_vasprintf(&udptl->tag, format, ap) == -1) {
01003       udptl->tag = NULL;
01004    }
01005    va_end(ap);
01006 }

void ast_udptl_setnat	(	struct ast_udptl *	udptl,
		int	nat
	)

Definition at line 647 of file udptl.c.

References ast_udptl::nat.

Referenced by do_setnat(), and initialize_udptl().

00648 {
00649    udptl->nat = nat;
00650 }

int ast_udptl_setqos	(	struct ast_udptl *	udptl,
		unsigned int	tos,
		unsigned int	cos
	)

Definition at line 1008 of file udptl.c.

References ast_netsock_set_qos(), and ast_udptl::fd.

Referenced by initialize_udptl().

01009 {
01010    return ast_netsock_set_qos(udptl->fd, tos, cos, "UDPTL");
01011 }

void ast_udptl_stop ( struct ast_udptl * udptl )

Definition at line 1028 of file udptl.c.

References ast_sockaddr_setnull(), and ast_udptl::them.

Referenced by process_sdp(), and stop_media_flows().

01029 {
01030    ast_sockaddr_setnull(&udptl->them);
01031 }

int ast_udptl_write	(	struct ast_udptl *	s,
		struct ast_frame *	f
	)

Definition at line 1044 of file udptl.c.

References AST_FRAME_MODEM, ast_log(), AST_MODEM_T38, ast_sendto(), ast_sockaddr_isnull(), ast_sockaddr_stringify(), ast_verb, ast_frame::data, ast_frame::datalen, DEFAULT_FAX_MAX_DATAGRAM, errno, ast_udptl::far_max_datagram, ast_udptl::far_max_ifp, ast_udptl::fd, ast_frame::frametype, ast_frame_subclass::integer, len(), LOG_NOTICE, LOG_TAG, LOG_WARNING, ast_frame::ptr, seq, ast_frame::subclass, ast_udptl::them, ast_udptl::tx_seq_no, udptl_build_packet(), and udptl_debug_test_addr().

Referenced by sip_write().

01045 {
01046    unsigned int seq;
01047    unsigned int len = f->datalen;
01048    /* if no max datagram size is provided, use default value */
01049    const int bufsize = (s->far_max_datagram > 0) ? s->far_max_datagram : DEFAULT_FAX_MAX_DATAGRAM;
01050    uint8_t buf[bufsize];
01051 
01052    memset(buf, 0, sizeof(buf));
01053 
01054    /* If we have no peer, return immediately */
01055    if (ast_sockaddr_isnull(&s->them)) {
01056       return 0;
01057    }
01058 
01059    /* If there is no data length, return immediately */
01060    if (f->datalen == 0)
01061       return 0;
01062    
01063    if ((f->frametype != AST_FRAME_MODEM) ||
01064        (f->subclass.integer != AST_MODEM_T38)) {
01065       ast_log(LOG_WARNING, "UDPTL (%s): UDPTL can only send T.38 data.\n",
01066          LOG_TAG(s));
01067       return -1;
01068    }
01069 
01070    if (len > s->far_max_ifp) {
01071       ast_log(LOG_WARNING,
01072          "UDPTL (%s): UDPTL asked to send %d bytes of IFP when far end only prepared to accept %d bytes; data loss will occur."
01073          "You may need to override the T38FaxMaxDatagram value for this endpoint in the channel driver configuration.\n",
01074          LOG_TAG(s), len, s->far_max_ifp);
01075       len = s->far_max_ifp;
01076    }
01077 
01078    /* Save seq_no for debug output because udptl_build_packet increments it */
01079    seq = s->tx_seq_no & 0xFFFF;
01080 
01081    /* Cook up the UDPTL packet, with the relevant EC info. */
01082    len = udptl_build_packet(s, buf, sizeof(buf), f->data.ptr, len);
01083 
01084    if ((signed int) len > 0 && !ast_sockaddr_isnull(&s->them)) {
01085       if (ast_sendto(s->fd, buf, len, 0, &s->them) < 0) {
01086          ast_log(LOG_NOTICE, "UDPTL (%s): Transmission error to %s: %s\n",
01087             LOG_TAG(s), ast_sockaddr_stringify(&s->them), strerror(errno));
01088       }
01089       if (udptl_debug_test_addr(&s->them)) {
01090          ast_verb(1, "UDPTL (%s): packet to %s (seq %d, len %d)\n",
01091             LOG_TAG(s), ast_sockaddr_stringify(&s->them), seq, len);
01092       }
01093    }
01094       
01095    return 0;
01096 }

static void calculate_far_max_ifp ( struct ast_udptl * udptl ) [static]

Definition at line 762 of file udptl.c.

References ast_log(), ast_udptl::error_correction_entries, ast_udptl::error_correction_scheme, ast_udptl::far_max_datagram, ast_udptl::far_max_ifp, LOG_TAG, LOG_WARNING, UDPTL_ERROR_CORRECTION_FEC, UDPTL_ERROR_CORRECTION_NONE, and UDPTL_ERROR_CORRECTION_REDUNDANCY.

Referenced by ast_udptl_get_far_max_ifp().

00763 {
00764    unsigned new_max = 0;
00765 
00766    if (udptl->far_max_datagram == -1) {
00767       ast_log(LOG_WARNING, "UDPTL (%s): Cannot calculate far_max_ifp before far_max_datagram has been set.\n",
00768          LOG_TAG(udptl));
00769       udptl->far_max_ifp = -1;
00770       return;
00771    }
00772 
00773    /* the goal here is to supply the local endpoint (application
00774     * or bridged channel) a maximum IFP value that will allow it
00775     * to effectively and efficiently transfer image data at its
00776     * selected bit rate, taking into account the selected error
00777     * correction mode, but without overrunning the far endpoint's
00778     * datagram buffer. this is complicated by the fact that some
00779     * far endpoints send us bogus (small) max datagram values,
00780     * which would result in either buffer overrun or no error
00781     * correction. we try to accomodate those, but if the supplied
00782     * value is too small to do so, we'll emit warning messages and
00783     * the user will have to use configuration options to override
00784     * the max datagram value supplied by the far endpoint.
00785     */
00786    switch (udptl->error_correction_scheme) {
00787    case UDPTL_ERROR_CORRECTION_NONE:
00788       /* need room for sequence number, length indicator, redundancy
00789        * indicator and following length indicator
00790        */
00791       new_max = udptl->far_max_datagram - 5;
00792       break;
00793    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00794       /* for this case, we'd like to send as many error correction entries
00795        * as possible (up to the number we're configured for), but we'll settle
00796        * for sending fewer if the configured number would cause the
00797        * calculated max IFP to be too small for effective operation
00798        *
00799        * need room for sequence number, length indicators and the
00800        * configured number of redundant packets
00801        *
00802        * note: we purposely don't allow error_correction_entries to drop to
00803        * zero in this loop; we'd rather send smaller IFPs (and thus reduce
00804        * the image data transfer rate) than sacrifice redundancy completely
00805        */
00806       for (;;) {
00807          new_max = (udptl->far_max_datagram - 8) / (udptl->error_correction_entries + 1);
00808 
00809          if ((new_max < 80) && (udptl->error_correction_entries > 1)) {
00810             /* the max ifp is not large enough, subtract an
00811              * error correction entry and calculate again
00812              * */
00813             --udptl->error_correction_entries;
00814          } else {
00815             break;
00816          }
00817       }
00818       break;
00819    case UDPTL_ERROR_CORRECTION_FEC:
00820       /* need room for sequence number, length indicators and a
00821        * a single IFP of the maximum size expected
00822        */
00823       new_max = (udptl->far_max_datagram - 10) / 2;
00824       break;
00825    }
00826    /* subtract 5% of space for insurance */
00827    udptl->far_max_ifp = new_max * 0.95;
00828 }

static void calculate_local_max_datagram ( struct ast_udptl * udptl ) [static]

Definition at line 721 of file udptl.c.

References ast_log(), ast_udptl::error_correction_scheme, LOCAL_FAX_MAX_DATAGRAM, ast_udptl::local_max_datagram, ast_udptl::local_max_ifp, LOG_TAG, LOG_WARNING, MIN, UDPTL_ERROR_CORRECTION_FEC, UDPTL_ERROR_CORRECTION_NONE, and UDPTL_ERROR_CORRECTION_REDUNDANCY.

Referenced by ast_udptl_get_local_max_datagram().

00722 {
00723    unsigned int new_max = 0;
00724 
00725    if (udptl->local_max_ifp == -1) {
00726       ast_log(LOG_WARNING, "UDPTL (%s): Cannot calculate local_max_datagram before local_max_ifp has been set.\n",
00727          LOG_TAG(udptl));
00728       udptl->local_max_datagram = -1;
00729       return;
00730    }
00731 
00732    /* calculate the amount of space required to receive an IFP
00733     * of the maximum size supported by the application/endpoint
00734     * that we are delivering them to (local endpoint), and add
00735     * the amount of space required to support the selected
00736     * error correction mode
00737     */
00738    switch (udptl->error_correction_scheme) {
00739    case UDPTL_ERROR_CORRECTION_NONE:
00740       /* need room for sequence number, length indicator, redundancy
00741        * indicator and following length indicator
00742        */
00743       new_max = 5 + udptl->local_max_ifp;
00744       break;
00745    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00746       /* need room for sequence number, length indicators, plus
00747        * room for up to 3 redundancy packets
00748        */
00749       new_max = 5 + udptl->local_max_ifp + 2 + (3 * udptl->local_max_ifp);
00750       break;
00751    case UDPTL_ERROR_CORRECTION_FEC:
00752       /* need room for sequence number, length indicators and a
00753        * a single IFP of the maximum size expected
00754        */
00755       new_max = 5 + udptl->local_max_ifp + 4 + udptl->local_max_ifp;
00756       break;
00757    }
00758    /* add 5% extra space for insurance, but no larger than LOCAL_FAX_MAX_DATAGRAM */
00759    udptl->local_max_datagram = MIN(new_max * 1.05, LOCAL_FAX_MAX_DATAGRAM);
00760 }

static int decode_length	(	uint8_t *	buf,
		unsigned int	limit,
		unsigned int *	len,
		unsigned int *	pvalue
	)			`[static]`

Definition at line 201 of file udptl.c.

References ast_debug.

Referenced by decode_open_type(), and udptl_rx_packet().

00202 {
00203    if (*len >= limit)
00204       return -1;
00205    if ((buf[*len] & 0x80) == 0) {
00206       *pvalue = buf[*len];
00207       (*len)++;
00208       return 0;
00209    }
00210    if ((buf[*len] & 0x40) == 0) {
00211       if (*len == limit - 1)
00212          return -1;
00213       *pvalue = (buf[*len] & 0x3F) << 8;
00214       (*len)++;
00215       *pvalue |= buf[*len];
00216       (*len)++;
00217       return 0;
00218    }
00219    *pvalue = (buf[*len] & 0x3F) << 14;
00220    (*len)++;
00221    /* We have a fragment.  Currently we don't process fragments. */
00222    ast_debug(1, "UDPTL packet with length greater than 16K received, decoding will fail\n");
00223    return 1;
00224 }

static int decode_open_type	(	uint8_t *	buf,
		unsigned int	limit,
		unsigned int *	len,
		const uint8_t **	p_object,
		unsigned int *	p_num_octets
	)			`[static]`

Definition at line 227 of file udptl.c.

References decode_length().

Referenced by udptl_rx_packet().

00228 {
00229    unsigned int octet_cnt = 0;
00230 
00231    if (decode_length(buf, limit, len, &octet_cnt) != 0)
00232       return -1;
00233 
00234    if (octet_cnt > 0) {
00235       /* Make sure the buffer contains at least the number of bits requested */
00236       if ((*len + octet_cnt) > limit)
00237          return -1;
00238 
00239       *p_num_octets = octet_cnt;
00240       *p_object = &buf[*len];
00241       *len += octet_cnt;
00242    }
00243 
00244    return 0;
00245 }

static unsigned int encode_length	(	uint8_t *	buf,
		unsigned int *	len,
		unsigned int	value
	)			`[static]`

Definition at line 248 of file udptl.c.

Referenced by encode_open_type(), and udptl_build_packet().

00249 {
00250    unsigned int multiplier;
00251 
00252    if (value < 0x80) {
00253       /* 1 octet */
00254       buf[*len] = value;
00255       (*len)++;
00256       return value;
00257    }
00258    if (value < 0x4000) {
00259       /* 2 octets */
00260       /* Set the first bit of the first octet */
00261       buf[*len] = ((0x8000 | value) >> 8) & 0xFF;
00262       (*len)++;
00263       buf[*len] = value & 0xFF;
00264       (*len)++;
00265       return value;
00266    }
00267    /* Fragmentation */
00268    multiplier = (value < 0x10000) ? (value >> 14) : 4;
00269    /* Set the first 2 bits of the octet */
00270    buf[*len] = 0xC0 | multiplier;
00271    (*len)++;
00272    return multiplier << 14;
00273 }

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
	)			`[static]`

Definition at line 276 of file udptl.c.

References ast_log(), encode_length(), LOG_ERROR, and LOG_TAG.

Referenced by udptl_build_packet().

00278 {
00279    unsigned int enclen;
00280    unsigned int octet_idx;
00281    uint8_t zero_byte;
00282 
00283    /* If open type is of zero length, add a single zero byte (10.1) */
00284    if (num_octets == 0) {
00285       zero_byte = 0;
00286       data = &zero_byte;
00287       num_octets = 1;
00288    }
00289    /* Encode the open type */
00290    for (octet_idx = 0; ; num_octets -= enclen, octet_idx += enclen) {
00291       if ((enclen = encode_length(buf, len, num_octets)) < 0)
00292          return -1;
00293       if (enclen + *len > buflen) {
00294          ast_log(LOG_ERROR, "UDPTL (%s): Buffer overflow detected (%d + %d > %d)\n",
00295             LOG_TAG(udptl), enclen, *len, buflen);
00296          return -1;
00297       }
00298       if (enclen > 0) {
00299          memcpy(&buf[*len], &data[octet_idx], enclen);
00300          *len += enclen;
00301       }
00302       if (enclen >= num_octets)
00303          break;
00304    }
00305 
00306    return 0;
00307 }

static struct ast_udptl_protocol* get_proto ( struct ast_channel * chan ) [static, read]

Definition at line 1122 of file udptl.c.

References AST_RWLIST_RDLOCK, AST_RWLIST_TRAVERSE, AST_RWLIST_UNLOCK, ast_udptl_protocol::list, ast_channel::tech, ast_channel_tech::type, and ast_udptl_protocol::type.

Referenced by ast_udptl_bridge().

01123 {
01124    struct ast_udptl_protocol *cur = NULL;
01125 
01126    AST_RWLIST_RDLOCK(&protos);
01127    AST_RWLIST_TRAVERSE(&protos, cur, list) {
01128       if (cur->type == chan->tech->type)
01129          break;
01130    }
01131    AST_RWLIST_UNLOCK(&protos);
01132 
01133    return cur;
01134 }

static char* handle_cli_udptl_set_debug	(	struct ast_cli_entry *	e,
		int	cmd,
		struct ast_cli_args *	a
	)			`[static]`

Definition at line 1261 of file udptl.c.

References ast_cli_args::argc, ast_cli_args::argv, ast_cli(), ast_free, ast_sockaddr_copy(), ast_sockaddr_resolve(), ast_sockaddr_stringify(), CLI_GENERATE, CLI_INIT, CLI_SHOWUSAGE, CLI_SUCCESS, ast_cli_entry::command, ast_cli_args::fd, udptldebugaddr, and ast_cli_entry::usage.

01262 {
01263    switch (cmd) {
01264    case CLI_INIT:
01265       e->command = "udptl set debug {on|off|ip}";
01266       e->usage = 
01267          "Usage: udptl set debug {on|off|ip host[:port]}\n"
01268          "       Enable or disable dumping of UDPTL packets.\n"
01269          "       If ip is specified, limit the dumped packets to those to and from\n"
01270          "       the specified 'host' with optional port.\n";
01271       return NULL;
01272    case CLI_GENERATE:
01273       return NULL;
01274    }
01275 
01276    if (a->argc < 4 || a->argc > 5)
01277       return CLI_SHOWUSAGE;
01278 
01279    if (a->argc == 4) {
01280       if (!strncasecmp(a->argv[3], "on", 2)) {
01281          udptldebug = 1;
01282          memset(&udptldebugaddr, 0, sizeof(udptldebugaddr));
01283          ast_cli(a->fd, "UDPTL Debugging Enabled\n");
01284       } else if (!strncasecmp(a->argv[3], "off", 3)) {
01285          udptldebug = 0;
01286          ast_cli(a->fd, "UDPTL Debugging Disabled\n");
01287       } else {
01288          return CLI_SHOWUSAGE;
01289       }
01290    } else {
01291       struct ast_sockaddr *addrs;
01292       if (strncasecmp(a->argv[3], "ip", 2))
01293          return CLI_SHOWUSAGE;
01294       if (!ast_sockaddr_resolve(&addrs, a->argv[4], 0, 0)) {
01295          return CLI_SHOWUSAGE;
01296       }
01297       ast_sockaddr_copy(&udptldebugaddr, &addrs[0]);
01298          ast_cli(a->fd, "UDPTL Debugging Enabled for IP: %s\n", ast_sockaddr_stringify(&udptldebugaddr));
01299       udptldebug = 1;
01300       ast_free(addrs);
01301    }
01302 
01303    return CLI_SUCCESS;
01304 }

static int udptl_build_packet	(	struct ast_udptl *	s,
		uint8_t *	buf,
		unsigned int	buflen,
		uint8_t *	ifp,
		unsigned int	ifp_len
	)			`[static]`

Definition at line 521 of file udptl.c.

References ast_debug, udptl_fec_tx_buffer_t::buf, udptl_fec_tx_buffer_t::buf_len, encode_length(), encode_open_type(), ast_udptl::error_correction_entries, ast_udptl::error_correction_scheme, ast_udptl::error_correction_span, len(), LOCAL_FAX_MAX_DATAGRAM, LOG_TAG, seq, ast_udptl::tx, ast_udptl::tx_seq_no, UDPTL_BUF_MASK, UDPTL_ERROR_CORRECTION_FEC, UDPTL_ERROR_CORRECTION_NONE, and UDPTL_ERROR_CORRECTION_REDUNDANCY.

Referenced by ast_udptl_write().

00522 {
00523    uint8_t fec[LOCAL_FAX_MAX_DATAGRAM * 2];
00524    int i;
00525    int j;
00526    int seq;
00527    int entry;
00528    int entries;
00529    int span;
00530    int m;
00531    unsigned int len;
00532    int limit;
00533    int high_tide;
00534 
00535    seq = s->tx_seq_no & 0xFFFF;
00536 
00537    /* Map the sequence number to an entry in the circular buffer */
00538    entry = seq & UDPTL_BUF_MASK;
00539 
00540    /* We save the message in a circular buffer, for generating FEC or
00541       redundancy sets later on. */
00542    s->tx[entry].buf_len = ifp_len;
00543    memcpy(s->tx[entry].buf, ifp, ifp_len);
00544    
00545    /* Build the UDPTLPacket */
00546 
00547    len = 0;
00548    /* Encode the sequence number */
00549    buf[len++] = (seq >> 8) & 0xFF;
00550    buf[len++] = seq & 0xFF;
00551 
00552    /* Encode the primary IFP packet */
00553    if (encode_open_type(s, buf, buflen, &len, ifp, ifp_len) < 0)
00554       return -1;
00555 
00556    /* Encode the appropriate type of error recovery information */
00557    switch (s->error_correction_scheme)
00558    {
00559    case UDPTL_ERROR_CORRECTION_NONE:
00560       /* Encode the error recovery type */
00561       buf[len++] = 0x00;
00562       /* The number of entries will always be zero, so it is pointless allowing
00563          for the fragmented case here. */
00564       if (encode_length(buf, &len, 0) < 0)
00565          return -1;
00566       break;
00567    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00568       /* Encode the error recovery type */
00569       buf[len++] = 0x00;
00570       if (s->tx_seq_no > s->error_correction_entries)
00571          entries = s->error_correction_entries;
00572       else
00573          entries = s->tx_seq_no;
00574       /* The number of entries will always be small, so it is pointless allowing
00575          for the fragmented case here. */
00576       if (encode_length(buf, &len, entries) < 0)
00577          return -1;
00578       /* Encode the elements */
00579       for (i = 0; i < entries; i++) {
00580          j = (entry - i - 1) & UDPTL_BUF_MASK;
00581          if (encode_open_type(s, buf, buflen, &len, s->tx[j].buf, s->tx[j].buf_len) < 0) {
00582             ast_debug(1, "UDPTL (%s): Encoding failed at i=%d, j=%d\n",
00583                  LOG_TAG(s), i, j);
00584             return -1;
00585          }
00586       }
00587       break;
00588    case UDPTL_ERROR_CORRECTION_FEC:
00589       span = s->error_correction_span;
00590       entries = s->error_correction_entries;
00591       if (seq < s->error_correction_span*s->error_correction_entries) {
00592          /* In the initial stages, wind up the FEC smoothly */
00593          entries = seq/s->error_correction_span;
00594          if (seq < s->error_correction_span)
00595             span = 0;
00596       }
00597       /* Encode the error recovery type */
00598       buf[len++] = 0x80;
00599       /* Span is defined as an inconstrained integer, which it dumb. It will only
00600          ever be a small value. Treat it as such. */
00601       buf[len++] = 1;
00602       buf[len++] = span;
00603       /* The number of entries is defined as a length, but will only ever be a small
00604          value. Treat it as such. */
00605       buf[len++] = entries;
00606       for (m = 0; m < entries; m++) {
00607          /* Make an XOR'ed entry the maximum length */
00608          limit = (entry + m) & UDPTL_BUF_MASK;
00609          high_tide = 0;
00610          for (i = (limit - span*entries) & UDPTL_BUF_MASK; i != limit; i = (i + entries) & UDPTL_BUF_MASK) {
00611             if (high_tide < s->tx[i].buf_len) {
00612                for (j = 0; j < high_tide; j++)
00613                   fec[j] ^= s->tx[i].buf[j];
00614                for ( ; j < s->tx[i].buf_len; j++)
00615                   fec[j] = s->tx[i].buf[j];
00616                high_tide = s->tx[i].buf_len;
00617             } else {
00618                for (j = 0; j < s->tx[i].buf_len; j++)
00619                   fec[j] ^= s->tx[i].buf[j];
00620             }
00621          }
00622          if (encode_open_type(s, buf, buflen, &len, fec, high_tide) < 0)
00623             return -1;
00624       }
00625       break;
00626    }
00627 
00628    s->tx_seq_no++;
00629    return len;
00630 }

static int udptl_debug_test_addr ( const struct ast_sockaddr * addr ) [inline, static]

Definition at line 185 of file udptl.c.

References ast_sockaddr_cmp(), ast_sockaddr_cmp_addr(), ast_sockaddr_isnull(), ast_sockaddr_port, and udptldebugaddr.

Referenced by ast_udptl_read(), and ast_udptl_write().

00186 {
00187    if (udptldebug == 0)
00188       return 0;
00189 
00190    if (ast_sockaddr_isnull(&udptldebugaddr)) {
00191       return 1;
00192    }
00193 
00194    if (ast_sockaddr_port(&udptldebugaddr)) {
00195       return !ast_sockaddr_cmp(&udptldebugaddr, addr);
00196    } else {
00197       return !ast_sockaddr_cmp_addr(&udptldebugaddr, addr);
00198    }
00199 }

static int udptl_rx_packet	(	struct ast_udptl *	s,
		uint8_t *	buf,
		unsigned int	len
	)			`[static]`

Definition at line 310 of file udptl.c.

References ARRAY_LEN, AST_FRAME_MODEM, AST_LIST_NEXT, AST_MODEM_T38, udptl_fec_rx_buffer_t::buf, udptl_fec_rx_buffer_t::buf_len, ast_frame::data, ast_frame::datalen, decode_length(), decode_open_type(), ast_udptl::f, udptl_fec_rx_buffer_t::fec, udptl_fec_rx_buffer_t::fec_entries, udptl_fec_rx_buffer_t::fec_len, udptl_fec_rx_buffer_t::fec_span, ast_frame::frametype, ast_frame_subclass::integer, LOCAL_FAX_MAX_DATAGRAM, ast_frame::mallocd, MAX_FEC_ENTRIES, ast_frame::offset, ast_frame::ptr, ast_udptl::rx, ast_udptl::rx_seq_no, ast_frame::seqno, ast_frame::src, ast_frame::subclass, TRUE, and UDPTL_BUF_MASK.

Referenced by ast_udptl_read().

00311 {
00312    int stat1;
00313    int stat2;
00314    int i;
00315    int j;
00316    int k;
00317    int l;
00318    int m;
00319    int x;
00320    int limit;
00321    int which;
00322    unsigned int ptr;
00323    unsigned int count;
00324    int total_count;
00325    int seq_no;
00326    const uint8_t *ifp = NULL;
00327    const uint8_t *data = NULL;
00328    unsigned int ifp_len = 0;
00329    int repaired[16];
00330    const uint8_t *bufs[ARRAY_LEN(s->f) - 1];
00331    unsigned int lengths[ARRAY_LEN(s->f) - 1];
00332    int span;
00333    int entries;
00334    int ifp_no;
00335 
00336    ptr = 0;
00337    ifp_no = 0;
00338    memset(&s->f[0], 0, sizeof(s->f[0]));
00339 
00340    /* Decode seq_number */
00341    if (ptr + 2 > len)
00342       return -1;
00343    seq_no = (buf[0] << 8) | buf[1];
00344    ptr += 2;
00345 
00346    /* Break out the primary packet */
00347    if ((stat1 = decode_open_type(buf, len, &ptr, &ifp, &ifp_len)) != 0)
00348       return -1;
00349    /* Decode error_recovery */
00350    if (ptr + 1 > len)
00351       return -1;
00352    if ((buf[ptr++] & 0x80) == 0) {
00353       /* Secondary packet mode for error recovery */
00354       if (seq_no > s->rx_seq_no) {
00355          /* We received a later packet than we expected, so we need to check if we can fill in the gap from the
00356             secondary packets. */
00357          total_count = 0;
00358          do {
00359             if ((stat2 = decode_length(buf, len, &ptr, &count)) < 0)
00360                return -1;
00361             for (i = 0; i < count && total_count + i < ARRAY_LEN(bufs); i++) {
00362                if ((stat1 = decode_open_type(buf, len, &ptr, &bufs[total_count + i], &lengths[total_count + i])) != 0)
00363                   return -1;
00364             }
00365             total_count += i;
00366          }
00367          while (stat2 > 0 && total_count < ARRAY_LEN(bufs));
00368          /* Step through in reverse order, so we go oldest to newest */
00369          for (i = total_count; i > 0; i--) {
00370             if (seq_no - i >= s->rx_seq_no) {
00371                /* This one wasn't seen before */
00372                /* Decode the secondary IFP packet */
00373                //fprintf(stderr, "Secondary %d, len %d\n", seq_no - i, lengths[i - 1]);
00374                s->f[ifp_no].frametype = AST_FRAME_MODEM;
00375                s->f[ifp_no].subclass.integer = AST_MODEM_T38;
00376 
00377                s->f[ifp_no].mallocd = 0;
00378                s->f[ifp_no].seqno = seq_no - i;
00379                s->f[ifp_no].datalen = lengths[i - 1];
00380                s->f[ifp_no].data.ptr = (uint8_t *) bufs[i - 1];
00381                s->f[ifp_no].offset = 0;
00382                s->f[ifp_no].src = "UDPTL";
00383                if (ifp_no > 0)
00384                   AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00385                AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00386                ifp_no++;
00387             }
00388          }
00389       }
00390    }
00391    else
00392    {
00393       /* FEC mode for error recovery */
00394       /* Our buffers cannot tolerate overlength IFP packets in FEC mode */
00395       if (ifp_len > LOCAL_FAX_MAX_DATAGRAM)
00396          return -1;
00397       /* Update any missed slots in the buffer */
00398       for ( ; seq_no > s->rx_seq_no; s->rx_seq_no++) {
00399          x = s->rx_seq_no & UDPTL_BUF_MASK;
00400          s->rx[x].buf_len = -1;
00401          s->rx[x].fec_len[0] = 0;
00402          s->rx[x].fec_span = 0;
00403          s->rx[x].fec_entries = 0;
00404       }
00405 
00406       x = seq_no & UDPTL_BUF_MASK;
00407 
00408       memset(repaired, 0, sizeof(repaired));
00409 
00410       /* Save the new IFP packet */
00411       memcpy(s->rx[x].buf, ifp, ifp_len);
00412       s->rx[x].buf_len = ifp_len;
00413       repaired[x] = TRUE;
00414 
00415       /* Decode the FEC packets */
00416       /* The span is defined as an unconstrained integer, but will never be more
00417          than a small value. */
00418       if (ptr + 2 > len)
00419          return -1;
00420       if (buf[ptr++] != 1)
00421          return -1;
00422       span = buf[ptr++];
00423       s->rx[x].fec_span = span;
00424 
00425       /* The number of entries is defined as a length, but will only ever be a small
00426          value. Treat it as such. */
00427       if (ptr + 1 > len)
00428          return -1;
00429       entries = buf[ptr++];
00430       if (entries > MAX_FEC_ENTRIES) {
00431          return -1;
00432       }
00433       s->rx[x].fec_entries = entries;
00434 
00435       /* Decode the elements */
00436       for (i = 0; i < entries; i++) {
00437          if ((stat1 = decode_open_type(buf, len, &ptr, &data, &s->rx[x].fec_len[i])) != 0)
00438             return -1;
00439          if (s->rx[x].fec_len[i] > LOCAL_FAX_MAX_DATAGRAM)
00440             return -1;
00441 
00442          /* Save the new FEC data */
00443          memcpy(s->rx[x].fec[i], data, s->rx[x].fec_len[i]);
00444 #if 0
00445          fprintf(stderr, "FEC: ");
00446          for (j = 0; j < s->rx[x].fec_len[i]; j++)
00447             fprintf(stderr, "%02X ", data[j]);
00448          fprintf(stderr, "\n");
00449 #endif
00450       }
00451 
00452       /* See if we can reconstruct anything which is missing */
00453       /* TODO: this does not comprehensively hunt back and repair everything that is possible */
00454       for (l = x; l != ((x - (16 - span*entries)) & UDPTL_BUF_MASK); l = (l - 1) & UDPTL_BUF_MASK) {
00455          if (s->rx[l].fec_len[0] <= 0)
00456             continue;
00457          for (m = 0; m < s->rx[l].fec_entries; m++) {
00458             limit = (l + m) & UDPTL_BUF_MASK;
00459             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) {
00460                if (s->rx[k].buf_len <= 0)
00461                   which = (which == -1) ? k : -2;
00462             }
00463             if (which >= 0) {
00464                /* Repairable */
00465                for (j = 0; j < s->rx[l].fec_len[m]; j++) {
00466                   s->rx[which].buf[j] = s->rx[l].fec[m][j];
00467                   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)
00468                      s->rx[which].buf[j] ^= (s->rx[k].buf_len > j) ? s->rx[k].buf[j] : 0;
00469                }
00470                s->rx[which].buf_len = s->rx[l].fec_len[m];
00471                repaired[which] = TRUE;
00472             }
00473          }
00474       }
00475       /* Now play any new packets forwards in time */
00476       for (l = (x + 1) & UDPTL_BUF_MASK, j = seq_no - UDPTL_BUF_MASK; l != x; l = (l + 1) & UDPTL_BUF_MASK, j++) {
00477          if (repaired[l]) {
00478             //fprintf(stderr, "Fixed packet %d, len %d\n", j, l);
00479             s->f[ifp_no].frametype = AST_FRAME_MODEM;
00480             s->f[ifp_no].subclass.integer = AST_MODEM_T38;
00481          
00482             s->f[ifp_no].mallocd = 0;
00483             s->f[ifp_no].seqno = j;
00484             s->f[ifp_no].datalen = s->rx[l].buf_len;
00485             s->f[ifp_no].data.ptr = s->rx[l].buf;
00486             s->f[ifp_no].offset = 0;
00487             s->f[ifp_no].src = "UDPTL";
00488             if (ifp_no > 0)
00489                AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00490             AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00491             ifp_no++;
00492          }
00493       }
00494    }
00495 
00496    /* If packets are received out of sequence, we may have already processed this packet from the error
00497       recovery information in a packet already received. */
00498    if (seq_no >= s->rx_seq_no) {
00499       /* Decode the primary IFP packet */
00500       s->f[ifp_no].frametype = AST_FRAME_MODEM;
00501       s->f[ifp_no].subclass.integer = AST_MODEM_T38;
00502       
00503       s->f[ifp_no].mallocd = 0;
00504       s->f[ifp_no].seqno = seq_no;
00505       s->f[ifp_no].datalen = ifp_len;
00506       s->f[ifp_no].data.ptr = (uint8_t *) ifp;
00507       s->f[ifp_no].offset = 0;
00508       s->f[ifp_no].src = "UDPTL";
00509       if (ifp_no > 0)
00510          AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00511       AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00512 
00513       ifp_no++;
00514    }
00515 
00516    s->rx_seq_no = seq_no + 1;
00517    return ifp_no;
00518 }

static int udptlread	(	int *	id,
		int	fd,
		short	events,
		void *	cbdata
	)			`[static]`

Definition at line 652 of file udptl.c.

References ast_udptl_read(), ast_udptl::callback, ast_udptl::data, and f.

Referenced by ast_udptl_new_with_bindaddr().

00653 {
00654    struct ast_udptl *udptl = cbdata;
00655    struct ast_frame *f;
00656 
00657    if ((f = ast_udptl_read(udptl))) {
00658       if (udptl->callback)
00659          udptl->callback(udptl, f, udptl->data);
00660    }
00661    return 1;
00662 }

Variable Documentation

struct ast_cli_entry cli_udptl[] [static]

Initial value:

 {
   AST_CLI_DEFINE(handle_cli_udptl_set_debug, "Enable/Disable UDPTL debugging")
}

Definition at line 1307 of file udptl.c.

int udptldebug [static]

Are we debugging?

Definition at line 87 of file udptl.c.

struct ast_sockaddr udptldebugaddr [static]

Debug packets to/from this host

Definition at line 88 of file udptl.c.

Referenced by handle_cli_udptl_set_debug(), and udptl_debug_test_addr().

int udptlend = DEFAULT_UDPTLEND [static]

Definition at line 86 of file udptl.c.

int udptlfecentries [static]

Definition at line 92 of file udptl.c.

int udptlfecspan [static]

Definition at line 93 of file udptl.c.

int udptlstart = DEFAULT_UDPTLSTART [static]

Definition at line 85 of file udptl.c.

int use_even_ports [static]

Definition at line 94 of file udptl.c.


Data Structures
struct	ast_udptl
	Structure for an UDPTL session. More...
struct	protos
struct	udptl_fec_rx_buffer_t
struct	udptl_fec_tx_buffer_t
Defines
#define	DEFAULT_FAX_MAX_DATAGRAM 400
#define	DEFAULT_UDPTLEND 4999
#define	DEFAULT_UDPTLSTART 4000
#define	FALSE 0
#define	FAX_MAX_DATAGRAM_LIMIT 1400
#define	LOCAL_FAX_MAX_DATAGRAM 1400
#define	LOG_TAG(u) S_OR(u->tag, "no tag")
#define	MAX_FEC_ENTRIES 5
#define	MAX_FEC_SPAN 5
#define	TRUE (!FALSE)
#define	UDPTL_BUF_MASK 15
#define	UDPTL_MTU 1200
Functions
static void	__ast_udptl_reload (int reload)
static void	__fini_protos (void)
static void	__init_protos (void)
int	ast_udptl_bridge (struct ast_channel c0, struct ast_channel c1, int flags, struct ast_frame fo, struct ast_channel rc)
void	ast_udptl_destroy (struct ast_udptl *udptl)
int	ast_udptl_fd (const struct ast_udptl *udptl)
enum ast_t38_ec_modes	ast_udptl_get_error_correction_scheme (const struct ast_udptl *udptl)
unsigned int	ast_udptl_get_far_max_datagram (const struct ast_udptl *udptl)
unsigned int	ast_udptl_get_far_max_ifp (struct ast_udptl *udptl)
	retrieves far max ifp
unsigned int	ast_udptl_get_local_max_datagram (struct ast_udptl *udptl)
	retrieves local_max_datagram.
void	ast_udptl_get_peer (const struct ast_udptl udptl, struct ast_sockaddr them)
void	ast_udptl_get_us (const struct ast_udptl udptl, struct ast_sockaddr us)
void	ast_udptl_init (void)
struct ast_udptl *	ast_udptl_new_with_bindaddr (struct ast_sched_context sched, struct io_context io, int callbackmode, struct ast_sockaddr *addr)
int	ast_udptl_proto_register (struct ast_udptl_protocol *proto)
void	ast_udptl_proto_unregister (struct ast_udptl_protocol *proto)
struct ast_frame *	ast_udptl_read (struct ast_udptl *udptl)
int	ast_udptl_reload (void)
void	ast_udptl_set_callback (struct ast_udptl *udptl, ast_udptl_callback callback)
void	ast_udptl_set_data (struct ast_udptl udptl, void data)
void	ast_udptl_set_error_correction_scheme (struct ast_udptl *udptl, enum ast_t38_ec_modes ec)
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 value.
void	ast_udptl_set_local_max_ifp (struct ast_udptl *udptl, unsigned int max_ifp)
void	ast_udptl_set_peer (struct ast_udptl udptl, const struct ast_sockaddr them)
void	ast_udptl_set_tag (struct ast_udptl udptl, const char format,...)
	Associates a character string 'tag' with a UDPTL session.
void	ast_udptl_setnat (struct ast_udptl *udptl, int nat)
int	ast_udptl_setqos (struct ast_udptl *udptl, unsigned int tos, unsigned int cos)
void	ast_udptl_stop (struct ast_udptl *udptl)
int	ast_udptl_write (struct ast_udptl s, struct ast_frame f)
static void	calculate_far_max_ifp (struct ast_udptl *udptl)
static void	calculate_local_max_datagram (struct ast_udptl *udptl)
static int	decode_length (uint8_t buf, unsigned int limit, unsigned int len, unsigned int *pvalue)
static int	decode_open_type (uint8_t buf, unsigned int limit, unsigned int len, const uint8_t *p_object, unsigned int p_num_octets)
static unsigned int	encode_length (uint8_t buf, unsigned int len, unsigned int value)
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)
static struct ast_udptl_protocol *	get_proto (struct ast_channel *chan)
static char *	handle_cli_udptl_set_debug (struct ast_cli_entry e, int cmd, struct ast_cli_args a)
static int	udptl_build_packet (struct ast_udptl s, uint8_t buf, unsigned int buflen, uint8_t *ifp, unsigned int ifp_len)
static int	udptl_debug_test_addr (const struct ast_sockaddr *addr)
static int	udptl_rx_packet (struct ast_udptl s, uint8_t buf, unsigned int len)
static int	udptlread (int id, int fd, short events, void cbdata)
Variables
static struct ast_cli_entry	cli_udptl []
static int	udptldebug
static struct ast_sockaddr	udptldebugaddr
static int	udptlend = DEFAULT_UDPTLEND
static int	udptlfecentries
static int	udptlfecspan
static int	udptlstart = DEFAULT_UDPTLSTART
static int	use_even_ports

Asterisk developer's documentation

udptl.c File Reference

Data Structures

Defines

Functions

Variables

Detailed Description

Define Documentation

Function Documentation

Variable Documentation