Tue Aug 20 16:35:17 2013

Asterisk developer's documentation


udptl.c File Reference

UDPTL support for T.38 faxing. More...

#include "asterisk.h"
#include <sys/time.h>
#include <signal.h>
#include <fcntl.h>
#include "asterisk/udptl.h"
#include "asterisk/frame.h"
#include "asterisk/channel.h"
#include "asterisk/acl.h"
#include "asterisk/config.h"
#include "asterisk/lock.h"
#include "asterisk/utils.h"
#include "asterisk/netsock.h"
#include "asterisk/cli.h"
#include "asterisk/unaligned.h"

Go to the source code of this file.

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 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 UDPTL_BUF_MASK   15
#define UDPTL_MTU   1200

Functions

static void __ast_udptl_reload (int reload)
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_udptlast_udptl_new_with_bindaddr (struct 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_frameast_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_protocolget_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 void udptl_shutdown (void)
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 = 4599
static int udptlfecentries
static int udptlfecspan
static int udptlstart = 4500
static int use_even_ports

Detailed Description

UDPTL support for T.38 faxing.

Author:
Mark Spencer <markster@digium.com>
Steve Underwood <steveu@coppice.org>
Kevin P. Fleming <kpfleming@digium.com>

Definition in file udptl.c.


Define Documentation

#define DEFAULT_FAX_MAX_DATAGRAM   400

Definition at line 97 of file udptl.c.

Referenced by ast_udptl_set_far_max_datagram(), and ast_udptl_write().

#define FAX_MAX_DATAGRAM_LIMIT   1400

Definition at line 98 of file udptl.c.

Referenced by ast_udptl_set_far_max_datagram().

#define LOCAL_FAX_MAX_DATAGRAM   1400

Definition at line 96 of file udptl.c.

Referenced by calculate_local_max_datagram(), udptl_build_packet(), and udptl_rx_packet().

#define LOG_TAG (  )     S_OR(u->tag, "no tag")
#define MAX_FEC_ENTRIES   5

Definition at line 99 of file udptl.c.

Referenced by __ast_udptl_reload(), and udptl_rx_packet().

#define MAX_FEC_SPAN   5

Definition at line 100 of file udptl.c.

Referenced by __ast_udptl_reload().

#define UDPTL_BUF_MASK   15

Definition at line 102 of file udptl.c.

Referenced by ast_udptl_new_with_bindaddr(), udptl_build_packet(), and udptl_rx_packet().

#define UDPTL_MTU   1200

Definition at line 74 of file udptl.c.


Function Documentation

static void __ast_udptl_reload ( int  reload  )  [static]

Definition at line 1315 of file udptl.c.

References ast_config_destroy(), ast_config_load2(), ast_false(), ast_log(), ast_true(), ast_variable_retrieve(), ast_verb, CONFIG_FLAG_FILEUNCHANGED, CONFIG_STATUS_FILEINVALID, CONFIG_STATUS_FILEMISSING, CONFIG_STATUS_FILEUNCHANGED, LOG_NOTICE, LOG_WARNING, MAX_FEC_ENTRIES, and MAX_FEC_SPAN.

Referenced by ast_udptl_init(), and ast_udptl_reload().

01316 {
01317    struct ast_config *cfg;
01318    const char *s;
01319    struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };
01320 
01321    cfg = ast_config_load2("udptl.conf", "udptl", config_flags);
01322    if (cfg == CONFIG_STATUS_FILEMISSING || cfg == CONFIG_STATUS_FILEUNCHANGED || cfg == CONFIG_STATUS_FILEINVALID) {
01323       return;
01324    }
01325 
01326    udptlstart = 4500;
01327    udptlend = 4999;
01328    udptlfecentries = 0;
01329    udptlfecspan = 0;
01330    use_even_ports = 0;
01331 
01332    if (cfg) {
01333       if ((s = ast_variable_retrieve(cfg, "general", "udptlstart"))) {
01334          udptlstart = atoi(s);
01335          if (udptlstart < 1024) {
01336             ast_log(LOG_WARNING, "Ports under 1024 are not allowed for T.38.\n");
01337             udptlstart = 1024;
01338          }
01339          if (udptlstart > 65535) {
01340             ast_log(LOG_WARNING, "Ports over 65535 are invalid.\n");
01341             udptlstart = 65535;
01342          }
01343       }
01344       if ((s = ast_variable_retrieve(cfg, "general", "udptlend"))) {
01345          udptlend = atoi(s);
01346          if (udptlend < 1024) {
01347             ast_log(LOG_WARNING, "Ports under 1024 are not allowed for T.38.\n");
01348             udptlend = 1024;
01349          }
01350          if (udptlend > 65535) {
01351             ast_log(LOG_WARNING, "Ports over 65535 are invalid.\n");
01352             udptlend = 65535;
01353          }
01354       }
01355       if ((s = ast_variable_retrieve(cfg, "general", "udptlchecksums"))) {
01356 #ifdef SO_NO_CHECK
01357          if (ast_false(s))
01358             nochecksums = 1;
01359          else
01360             nochecksums = 0;
01361 #else
01362          if (ast_false(s))
01363             ast_log(LOG_WARNING, "Disabling UDPTL checksums is not supported on this operating system!\n");
01364 #endif
01365       }
01366       if (ast_variable_retrieve(cfg, "general", "T38FaxUdpEC")) {
01367          ast_log(LOG_WARNING, "T38FaxUdpEC in udptl.conf is no longer supported; use the t38pt_udptl configuration option in sip.conf instead.\n");
01368       }
01369       if (ast_variable_retrieve(cfg, "general", "T38FaxMaxDatagram")) {
01370          ast_log(LOG_WARNING, "T38FaxMaxDatagram in udptl.conf is no longer supported; value is now supplied by T.38 applications.\n");
01371       }
01372       if ((s = ast_variable_retrieve(cfg, "general", "UDPTLFECEntries"))) {
01373          udptlfecentries = atoi(s);
01374          if (udptlfecentries < 1) {
01375             ast_log(LOG_WARNING, "Too small UDPTLFECEntries value.  Defaulting to 1.\n");
01376             udptlfecentries = 1;
01377          }
01378          if (udptlfecentries > MAX_FEC_ENTRIES) {
01379             ast_log(LOG_WARNING, "Too large UDPTLFECEntries value.  Defaulting to %d.\n", MAX_FEC_ENTRIES);
01380             udptlfecentries = MAX_FEC_ENTRIES;
01381          }
01382       }
01383       if ((s = ast_variable_retrieve(cfg, "general", "UDPTLFECSpan"))) {
01384          udptlfecspan = atoi(s);
01385          if (udptlfecspan < 1) {
01386             ast_log(LOG_WARNING, "Too small UDPTLFECSpan value.  Defaulting to 1.\n");
01387             udptlfecspan = 1;
01388          }
01389          if (udptlfecspan > MAX_FEC_SPAN) {
01390             ast_log(LOG_WARNING, "Too large UDPTLFECSpan value.  Defaulting to %d.\n", MAX_FEC_SPAN);
01391             udptlfecspan = MAX_FEC_SPAN;
01392          }
01393       }
01394       if ((s = ast_variable_retrieve(cfg, "general", "use_even_ports"))) {
01395          use_even_ports = ast_true(s);
01396       }
01397       ast_config_destroy(cfg);
01398    }
01399    if (udptlstart >= udptlend) {
01400       ast_log(LOG_WARNING, "Unreasonable values for UDPTL start/end ports; defaulting to 4500-4999.\n");
01401       udptlstart = 4500;
01402       udptlend = 4999;
01403    }
01404    if (use_even_ports && (udptlstart & 1)) {
01405       ++udptlstart;
01406       ast_log(LOG_NOTICE, "Odd numbered udptlstart specified but use_even_ports enabled. udptlstart is now %d\n", udptlstart);
01407    }
01408    if (use_even_ports && (udptlend & 1)) {
01409       --udptlend;
01410       ast_log(LOG_NOTICE, "Odd numbered udptlend specified but use_event_ports enabled. udptlend is now %d\n", udptlend);
01411    }
01412    ast_verb(2, "UDPTL allocating from port range %d -> %d\n", udptlstart, udptlend);
01413 }

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 1140 of file udptl.c.

References ast_channel_lock, 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.

01141 {
01142    struct ast_frame *f;
01143    struct ast_channel *who;
01144    struct ast_channel *cs[3];
01145    struct ast_udptl *p0;
01146    struct ast_udptl *p1;
01147    struct ast_udptl_protocol *pr0;
01148    struct ast_udptl_protocol *pr1;
01149    struct ast_sockaddr ac0;
01150    struct ast_sockaddr ac1;
01151    struct ast_sockaddr t0;
01152    struct ast_sockaddr t1;
01153    void *pvt0;
01154    void *pvt1;
01155    int to;
01156    
01157    ast_channel_lock(c0);
01158    while (ast_channel_trylock(c1)) {
01159       ast_channel_unlock(c0);
01160       usleep(1);
01161       ast_channel_lock(c0);
01162    }
01163    pr0 = get_proto(c0);
01164    pr1 = get_proto(c1);
01165    if (!pr0) {
01166       ast_log(LOG_WARNING, "Can't find native functions for channel '%s'\n", c0->name);
01167       ast_channel_unlock(c0);
01168       ast_channel_unlock(c1);
01169       return -1;
01170    }
01171    if (!pr1) {
01172       ast_log(LOG_WARNING, "Can't find native functions for channel '%s'\n", c1->name);
01173       ast_channel_unlock(c0);
01174       ast_channel_unlock(c1);
01175       return -1;
01176    }
01177    pvt0 = c0->tech_pvt;
01178    pvt1 = c1->tech_pvt;
01179    p0 = pr0->get_udptl_info(c0);
01180    p1 = pr1->get_udptl_info(c1);
01181    if (!p0 || !p1) {
01182       /* Somebody doesn't want to play... */
01183       ast_channel_unlock(c0);
01184       ast_channel_unlock(c1);
01185       return -2;
01186    }
01187    if (pr0->set_udptl_peer(c0, p1)) {
01188       ast_log(LOG_WARNING, "Channel '%s' failed to talk to '%s'\n", c0->name, c1->name);
01189       memset(&ac1, 0, sizeof(ac1));
01190    } else {
01191       /* Store UDPTL peer */
01192       ast_udptl_get_peer(p1, &ac1);
01193    }
01194    if (pr1->set_udptl_peer(c1, p0)) {
01195       ast_log(LOG_WARNING, "Channel '%s' failed to talk back to '%s'\n", c1->name, c0->name);
01196       memset(&ac0, 0, sizeof(ac0));
01197    } else {
01198       /* Store UDPTL peer */
01199       ast_udptl_get_peer(p0, &ac0);
01200    }
01201    ast_channel_unlock(c0);
01202    ast_channel_unlock(c1);
01203    cs[0] = c0;
01204    cs[1] = c1;
01205    cs[2] = NULL;
01206    for (;;) {
01207       if ((c0->tech_pvt != pvt0) ||
01208          (c1->tech_pvt != pvt1) ||
01209          (c0->masq || c0->masqr || c1->masq || c1->masqr)) {
01210             ast_debug(1, "Oooh, something is weird, backing out\n");
01211             /* Tell it to try again later */
01212             return -3;
01213       }
01214       to = -1;
01215       ast_udptl_get_peer(p1, &t1);
01216       ast_udptl_get_peer(p0, &t0);
01217       if (ast_sockaddr_cmp(&t1, &ac1)) {
01218          ast_debug(1, "Oooh, '%s' changed end address to %s\n", 
01219             c1->name, ast_sockaddr_stringify(&t1));
01220          ast_debug(1, "Oooh, '%s' was %s\n", 
01221             c1->name, ast_sockaddr_stringify(&ac1));
01222          ast_sockaddr_copy(&ac1, &t1);
01223       }
01224       if (ast_sockaddr_cmp(&t0, &ac0)) {
01225          ast_debug(1, "Oooh, '%s' changed end address to %s\n", 
01226             c0->name, ast_sockaddr_stringify(&t0));
01227          ast_debug(1, "Oooh, '%s' was %s\n", 
01228             c0->name, ast_sockaddr_stringify(&ac0));
01229          ast_sockaddr_copy(&ac0, &t0);
01230       }
01231       who = ast_waitfor_n(cs, 2, &to);
01232       if (!who) {
01233          ast_debug(1, "Ooh, empty read...\n");
01234          /* check for hangup / whentohangup */
01235          if (ast_check_hangup(c0) || ast_check_hangup(c1))
01236             break;
01237          continue;
01238       }
01239       f = ast_read(who);
01240       if (!f) {
01241          *fo = f;
01242          *rc = who;
01243          ast_debug(1, "Oooh, got a %s\n", f ? "digit" : "hangup");
01244          /* That's all we needed */
01245          return 0;
01246       } else {
01247          if (f->frametype == AST_FRAME_MODEM) {
01248             /* Forward T.38 frames if they happen upon us */
01249             if (who == c0) {
01250                ast_write(c1, f);
01251             } else if (who == c1) {
01252                ast_write(c0, f);
01253             }
01254          }
01255          ast_frfree(f);
01256       }
01257       /* Swap priority. Not that it's a big deal at this point */
01258       cs[2] = cs[0];
01259       cs[0] = cs[1];
01260       cs[1] = cs[2];
01261    }
01262    return -1;
01263 }

void ast_udptl_destroy ( struct ast_udptl udptl  ) 

Definition at line 1038 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().

01039 {
01040    if (udptl->ioid)
01041       ast_io_remove(udptl->io, udptl->ioid);
01042    if (udptl->fd > -1)
01043       close(udptl->fd);
01044    if (udptl->tag)
01045       ast_free(udptl->tag);
01046    ast_free(udptl);
01047 }

int ast_udptl_fd ( const struct ast_udptl udptl  ) 

Definition at line 637 of file udptl.c.

References ast_udptl::fd.

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

00638 {
00639    return udptl->fd;
00640 }

enum ast_t38_ec_modes ast_udptl_get_error_correction_scheme ( const struct ast_udptl udptl  ) 

Definition at line 835 of file udptl.c.

References ast_udptl::error_correction_scheme.

Referenced by add_sdp().

00836 {
00837    return udptl->error_correction_scheme;
00838 }

unsigned int ast_udptl_get_far_max_datagram ( const struct ast_udptl udptl  ) 

Definition at line 903 of file udptl.c.

References ast_udptl::far_max_datagram.

Referenced by process_sdp().

00904 {
00905    if (udptl->far_max_datagram < 0) {
00906       return 0;
00907    }
00908    return udptl->far_max_datagram;
00909 }

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 911 of file udptl.c.

References calculate_far_max_ifp(), and ast_udptl::far_max_ifp.

Referenced by change_t38_state(), and interpret_t38_parameters().

00912 {
00913    if (udptl->far_max_ifp == -1) {
00914       calculate_far_max_ifp(udptl);
00915    }
00916 
00917    if (udptl->far_max_ifp < 0) {
00918       return 0;
00919    }
00920    return udptl->far_max_ifp;
00921 }

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 879 of file udptl.c.

References calculate_local_max_datagram(), and ast_udptl::local_max_datagram.

Referenced by add_sdp().

00880 {
00881    if (udptl->local_max_datagram == -1) {
00882       calculate_local_max_datagram(udptl);
00883    }
00884 
00885    /* this function expects a unsigned value in return. */
00886    if (udptl->local_max_datagram < 0) {
00887       return 0;
00888    }
00889    return udptl->local_max_datagram;
00890 }

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

Definition at line 1023 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::them.

Referenced by ast_udptl_bridge(), and sip_set_udptl_peer().

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

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

Definition at line 1028 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::us.

Referenced by add_sdp().

01029 {
01030    ast_sockaddr_copy(us, &udptl->us);
01031 }

void ast_udptl_init ( void   ) 
struct ast_udptl* ast_udptl_new_with_bindaddr ( struct sched_context sched,
struct io_context io,
int  callbackmode,
struct ast_sockaddr addr 
) [read]

Definition at line 923 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().

00924 {
00925    struct ast_udptl *udptl;
00926    int x;
00927    int startplace;
00928    int i;
00929    long int flags;
00930 
00931    if (!(udptl = ast_calloc(1, sizeof(*udptl))))
00932       return NULL;
00933 
00934    udptl->error_correction_span = udptlfecspan;
00935    udptl->error_correction_entries = udptlfecentries;
00936    
00937    udptl->far_max_datagram = -1;
00938    udptl->far_max_ifp = -1;
00939    udptl->local_max_ifp = -1;
00940    udptl->local_max_datagram = -1;
00941 
00942    for (i = 0; i <= UDPTL_BUF_MASK; i++) {
00943       udptl->rx[i].buf_len = -1;
00944       udptl->tx[i].buf_len = -1;
00945    }
00946 
00947    if ((udptl->fd = socket(ast_sockaddr_is_ipv6(addr) ?
00948                AF_INET6 : AF_INET, SOCK_DGRAM, 0)) < 0) {
00949       ast_free(udptl);
00950       ast_log(LOG_WARNING, "Unable to allocate socket: %s\n", strerror(errno));
00951       return NULL;
00952    }
00953    flags = fcntl(udptl->fd, F_GETFL);
00954    fcntl(udptl->fd, F_SETFL, flags | O_NONBLOCK);
00955 #ifdef SO_NO_CHECK
00956    if (nochecksums)
00957       setsockopt(udptl->fd, SOL_SOCKET, SO_NO_CHECK, &nochecksums, sizeof(nochecksums));
00958 #endif
00959    /* Find us a place */
00960    x = (udptlstart == udptlend) ? udptlstart : (ast_random() % (udptlend - udptlstart)) + udptlstart;
00961    if (use_even_ports && (x & 1)) {
00962       ++x;
00963    }
00964    startplace = x;
00965    for (;;) {
00966       ast_sockaddr_copy(&udptl->us, addr);
00967       ast_sockaddr_set_port(&udptl->us, x);
00968       if (ast_bind(udptl->fd, &udptl->us) == 0) {
00969          break;
00970       }
00971       if (errno != EADDRINUSE) {
00972          ast_log(LOG_WARNING, "Unexpected bind error: %s\n", strerror(errno));
00973          close(udptl->fd);
00974          ast_free(udptl);
00975          return NULL;
00976       }
00977       if (use_even_ports) {
00978          x += 2;
00979       } else {
00980          ++x;
00981       }
00982       if (x > udptlend)
00983          x = udptlstart;
00984       if (x == startplace) {
00985          ast_log(LOG_WARNING, "No UDPTL ports remaining\n");
00986          close(udptl->fd);
00987          ast_free(udptl);
00988          return NULL;
00989       }
00990    }
00991    if (io && sched && callbackmode) {
00992       /* Operate this one in a callback mode */
00993       udptl->sched = sched;
00994       udptl->io = io;
00995       udptl->ioid = ast_io_add(udptl->io, udptl->fd, udptlread, AST_IO_IN, udptl);
00996    }
00997    return udptl;
00998 }

int ast_udptl_proto_register ( struct ast_udptl_protocol proto  ) 

Definition at line 1109 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().

01110 {
01111    struct ast_udptl_protocol *cur;
01112 
01113    AST_RWLIST_WRLOCK(&protos);
01114    AST_RWLIST_TRAVERSE(&protos, cur, list) {
01115       if (cur->type == proto->type) {
01116          ast_log(LOG_WARNING, "Tried to register same protocol '%s' twice\n", cur->type);
01117          AST_RWLIST_UNLOCK(&protos);
01118          return -1;
01119       }
01120    }
01121    AST_RWLIST_INSERT_TAIL(&protos, proto, list);
01122    AST_RWLIST_UNLOCK(&protos);
01123    return 0;
01124 }

void ast_udptl_proto_unregister ( struct ast_udptl_protocol proto  ) 

Definition at line 1102 of file udptl.c.

References AST_RWLIST_REMOVE, AST_RWLIST_UNLOCK, and AST_RWLIST_WRLOCK.

Referenced by unload_module().

01103 {
01104    AST_RWLIST_WRLOCK(&protos);
01105    AST_RWLIST_REMOVE(&protos, proto, list);
01106    AST_RWLIST_UNLOCK(&protos);
01107 }

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

Definition at line 669 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().

00670 {
00671    int res;
00672    struct ast_sockaddr addr;
00673    uint8_t *buf;
00674 
00675    buf = udptl->rawdata + AST_FRIENDLY_OFFSET;
00676 
00677    /* Cache where the header will go */
00678    res = ast_recvfrom(udptl->fd,
00679          buf,
00680          sizeof(udptl->rawdata) - AST_FRIENDLY_OFFSET,
00681          0,
00682          &addr);
00683    if (res < 0) {
00684       if (errno != EAGAIN)
00685          ast_log(LOG_WARNING, "UDPTL (%s): read error: %s\n",
00686             LOG_TAG(udptl), strerror(errno));
00687       ast_assert(errno != EBADF);
00688       return &ast_null_frame;
00689    }
00690 
00691    /* Ignore if the other side hasn't been given an address yet. */
00692    if (ast_sockaddr_isnull(&udptl->them)) {
00693       return &ast_null_frame;
00694    }
00695 
00696    if (udptl->nat) {
00697       /* Send to whoever sent to us */
00698       if (ast_sockaddr_cmp(&udptl->them, &addr)) {
00699          ast_sockaddr_copy(&udptl->them, &addr);
00700          ast_debug(1, "UDPTL (%s): NAT, Using address %s\n",
00701               LOG_TAG(udptl), ast_sockaddr_stringify(&udptl->them));
00702       }
00703    }
00704 
00705    if (udptl_debug_test_addr(&addr)) {
00706       int seq_no;
00707 
00708       /* Decode sequence number just for verbose message. */
00709       if (res < 2) {
00710          /* Short packet. */
00711          seq_no = -1;
00712       } else {
00713          seq_no = (buf[0] << 8) | buf[1];
00714       }
00715 
00716       ast_verb(1, "UDPTL (%s): packet from %s (seq %d, len %d)\n",
00717          LOG_TAG(udptl), ast_sockaddr_stringify(&addr), seq_no, res);
00718    }
00719    if (udptl_rx_packet(udptl, buf, res) < 1) {
00720       return &ast_null_frame;
00721    }
00722 
00723    return &udptl->f[0];
00724 }

int ast_udptl_reload ( void   ) 
Version:
1.6.1 return changed to int

Definition at line 1415 of file udptl.c.

References __ast_udptl_reload().

01416 {
01417    __ast_udptl_reload(1);
01418    return 0;
01419 }

void ast_udptl_set_callback ( struct ast_udptl udptl,
ast_udptl_callback  callback 
)

Definition at line 647 of file udptl.c.

References ast_udptl::callback.

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

void ast_udptl_set_data ( struct ast_udptl udptl,
void *  data 
)

Definition at line 642 of file udptl.c.

References ast_udptl::data.

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

void ast_udptl_set_error_correction_scheme ( struct ast_udptl udptl,
enum ast_t38_ec_modes  ec 
)

Definition at line 840 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().

00841 {
00842    udptl->error_correction_scheme = ec;
00843    switch (ec) {
00844    case UDPTL_ERROR_CORRECTION_FEC:
00845       udptl->error_correction_scheme = UDPTL_ERROR_CORRECTION_FEC;
00846       if (udptl->error_correction_entries == 0) {
00847          udptl->error_correction_entries = 3;
00848       }
00849       if (udptl->error_correction_span == 0) {
00850          udptl->error_correction_span = 3;
00851       }
00852       break;
00853    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00854       udptl->error_correction_scheme = UDPTL_ERROR_CORRECTION_REDUNDANCY;
00855       if (udptl->error_correction_entries == 0) {
00856          udptl->error_correction_entries = 3;
00857       }
00858       break;
00859    default:
00860       /* nothing to do */
00861       break;
00862    };
00863    /* reset calculated values so they'll be computed again */
00864    udptl->local_max_datagram = -1;
00865    udptl->far_max_ifp = -1;
00866 }

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 892 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().

00893 {
00894    if (!max_datagram || (max_datagram > FAX_MAX_DATAGRAM_LIMIT)) {
00895       udptl->far_max_datagram = DEFAULT_FAX_MAX_DATAGRAM;
00896    } else {
00897       udptl->far_max_datagram = max_datagram;
00898    }
00899    /* reset calculated values so they'll be computed again */
00900    udptl->far_max_ifp = -1;
00901 }

void ast_udptl_set_local_max_ifp ( struct ast_udptl udptl,
unsigned int  max_ifp 
)

Definition at line 868 of file udptl.c.

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

Referenced by interpret_t38_parameters().

00869 {
00870    /* make sure max_ifp is a positive value since a cast will take place when
00871     * when setting local_max_ifp */
00872    if ((signed int) max_ifp > 0) {
00873       udptl->local_max_ifp = max_ifp;
00874       /* reset calculated values so they'll be computed again */
00875       udptl->local_max_datagram = -1;
00876    }
00877 }

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

Definition at line 1018 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::them.

Referenced by process_sdp().

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

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 1000 of file udptl.c.

References ast_free, ast_vasprintf, and ast_udptl::tag.

Referenced by change_t38_state().

01001 {
01002    va_list ap;
01003 
01004    ast_free(udptl->tag);
01005    udptl->tag = NULL;
01006    va_start(ap, format);
01007    if (ast_vasprintf(&udptl->tag, format, ap) == -1) {
01008       udptl->tag = NULL;
01009    }
01010    va_end(ap);
01011 }

void ast_udptl_setnat ( struct ast_udptl udptl,
int  nat 
)

Definition at line 652 of file udptl.c.

References ast_udptl::nat.

Referenced by do_setnat(), and initialize_udptl().

00653 {
00654    udptl->nat = nat;
00655 }

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

Definition at line 1013 of file udptl.c.

References ast_netsock_set_qos(), and ast_udptl::fd.

Referenced by initialize_udptl().

01014 {
01015    return ast_netsock_set_qos(udptl->fd, tos, cos, "UDPTL");
01016 }

void ast_udptl_stop ( struct ast_udptl udptl  ) 

Definition at line 1033 of file udptl.c.

References ast_sockaddr_setnull(), and ast_udptl::them.

Referenced by process_sdp(), and stop_media_flows().

01034 {
01035    ast_sockaddr_setnull(&udptl->them);
01036 }

int ast_udptl_write ( struct ast_udptl s,
struct ast_frame f 
)

Definition at line 1049 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_subclass::codec, 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, 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().

01050 {
01051    unsigned int seq;
01052    unsigned int len = f->datalen;
01053    int res;
01054    /* if no max datagram size is provided, use default value */
01055    const int bufsize = (s->far_max_datagram > 0) ? s->far_max_datagram : DEFAULT_FAX_MAX_DATAGRAM;
01056    uint8_t buf[bufsize];
01057 
01058    memset(buf, 0, sizeof(buf));
01059 
01060    /* If we have no peer, return immediately */
01061    if (ast_sockaddr_isnull(&s->them)) {
01062       return 0;
01063    }
01064 
01065    /* If there is no data length, return immediately */
01066    if (f->datalen == 0)
01067       return 0;
01068    
01069    if ((f->frametype != AST_FRAME_MODEM) ||
01070        (f->subclass.codec != AST_MODEM_T38)) {
01071       ast_log(LOG_WARNING, "UDPTL (%s): UDPTL can only send T.38 data.\n",
01072          LOG_TAG(s));
01073       return -1;
01074    }
01075 
01076    if (len > s->far_max_ifp) {
01077       ast_log(LOG_WARNING,
01078          "UDPTL (%s): UDPTL asked to send %d bytes of IFP when far end only prepared to accept %d bytes; data loss will occur."
01079          "You may need to override the T38FaxMaxDatagram value for this endpoint in the channel driver configuration.\n",
01080          LOG_TAG(s), len, s->far_max_ifp);
01081       len = s->far_max_ifp;
01082    }
01083 
01084    /* Save seq_no for debug output because udptl_build_packet increments it */
01085    seq = s->tx_seq_no & 0xFFFF;
01086 
01087    /* Cook up the UDPTL packet, with the relevant EC info. */
01088    len = udptl_build_packet(s, buf, sizeof(buf), f->data.ptr, len);
01089 
01090    if ((signed int) len > 0 && !ast_sockaddr_isnull(&s->them)) {
01091       if ((res = ast_sendto(s->fd, buf, len, 0, &s->them)) < 0)
01092          ast_log(LOG_NOTICE, "UDPTL (%s): Transmission error to %s: %s\n",
01093             LOG_TAG(s), ast_sockaddr_stringify(&s->them), strerror(errno));
01094       if (udptl_debug_test_addr(&s->them))
01095          ast_verb(1, "UDPTL (%s): packet to %s (seq %d, len %d)\n",
01096             LOG_TAG(s), ast_sockaddr_stringify(&s->them), seq, len);
01097    }
01098       
01099    return 0;
01100 }

static void calculate_far_max_ifp ( struct ast_udptl udptl  )  [static]

Definition at line 767 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().

00768 {
00769    unsigned new_max = 0;
00770 
00771    if (udptl->far_max_datagram == -1) {
00772       ast_log(LOG_WARNING, "UDPTL (%s): Cannot calculate far_max_ifp before far_max_datagram has been set.\n",
00773          LOG_TAG(udptl));
00774       udptl->far_max_ifp = -1;
00775       return;
00776    }
00777 
00778    /* the goal here is to supply the local endpoint (application
00779     * or bridged channel) a maximum IFP value that will allow it
00780     * to effectively and efficiently transfer image data at its
00781     * selected bit rate, taking into account the selected error
00782     * correction mode, but without overrunning the far endpoint's
00783     * datagram buffer. this is complicated by the fact that some
00784     * far endpoints send us bogus (small) max datagram values,
00785     * which would result in either buffer overrun or no error
00786     * correction. we try to accomodate those, but if the supplied
00787     * value is too small to do so, we'll emit warning messages and
00788     * the user will have to use configuration options to override
00789     * the max datagram value supplied by the far endpoint.
00790     */
00791    switch (udptl->error_correction_scheme) {
00792    case UDPTL_ERROR_CORRECTION_NONE:
00793       /* need room for sequence number, length indicator, redundancy
00794        * indicator and following length indicator
00795        */
00796       new_max = udptl->far_max_datagram - 5;
00797       break;
00798    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00799       /* for this case, we'd like to send as many error correction entries
00800        * as possible (up to the number we're configured for), but we'll settle
00801        * for sending fewer if the configured number would cause the
00802        * calculated max IFP to be too small for effective operation
00803        *
00804        * need room for sequence number, length indicators and the
00805        * configured number of redundant packets
00806        *
00807        * note: we purposely don't allow error_correction_entries to drop to
00808        * zero in this loop; we'd rather send smaller IFPs (and thus reduce
00809        * the image data transfer rate) than sacrifice redundancy completely
00810        */
00811       for (;;) {
00812          new_max = (udptl->far_max_datagram - 8) / (udptl->error_correction_entries + 1);
00813 
00814          if ((new_max < 80) && (udptl->error_correction_entries > 1)) {
00815             /* the max ifp is not large enough, subtract an
00816              * error correction entry and calculate again
00817              * */
00818             --udptl->error_correction_entries;
00819          } else {
00820             break;
00821          }
00822       }
00823       break;
00824    case UDPTL_ERROR_CORRECTION_FEC:
00825       /* need room for sequence number, length indicators and a
00826        * a single IFP of the maximum size expected
00827        */
00828       new_max = (udptl->far_max_datagram - 10) / 2;
00829       break;
00830    }
00831    /* subtract 5% of space for insurance */
00832    udptl->far_max_ifp = new_max * 0.95;
00833 }

static void calculate_local_max_datagram ( struct ast_udptl udptl  )  [static]

Definition at line 726 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().

00727 {
00728    unsigned int new_max = 0;
00729 
00730    if (udptl->local_max_ifp == -1) {
00731       ast_log(LOG_WARNING, "UDPTL (%s): Cannot calculate local_max_datagram before local_max_ifp has been set.\n",
00732          LOG_TAG(udptl));
00733       udptl->local_max_datagram = -1;
00734       return;
00735    }
00736 
00737    /* calculate the amount of space required to receive an IFP
00738     * of the maximum size supported by the application/endpoint
00739     * that we are delivering them to (local endpoint), and add
00740     * the amount of space required to support the selected
00741     * error correction mode
00742     */
00743    switch (udptl->error_correction_scheme) {
00744    case UDPTL_ERROR_CORRECTION_NONE:
00745       /* need room for sequence number, length indicator, redundancy
00746        * indicator and following length indicator
00747        */
00748       new_max = 5 + udptl->local_max_ifp;
00749       break;
00750    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00751       /* need room for sequence number, length indicators, plus
00752        * room for up to 3 redundancy packets
00753        */
00754       new_max = 5 + udptl->local_max_ifp + 2 + (3 * udptl->local_max_ifp);
00755       break;
00756    case UDPTL_ERROR_CORRECTION_FEC:
00757       /* need room for sequence number, length indicators and a
00758        * a single IFP of the maximum size expected
00759        */
00760       new_max = 5 + udptl->local_max_ifp + 4 + udptl->local_max_ifp;
00761       break;
00762    }
00763    /* add 5% extra space for insurance, but no larger than LOCAL_FAX_MAX_DATAGRAM */
00764    udptl->local_max_datagram = MIN(new_max * 1.05, LOCAL_FAX_MAX_DATAGRAM);
00765 }

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 1126 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().

01127 {
01128    struct ast_udptl_protocol *cur = NULL;
01129 
01130    AST_RWLIST_RDLOCK(&protos);
01131    AST_RWLIST_TRAVERSE(&protos, cur, list) {
01132       if (cur->type == chan->tech->type)
01133          break;
01134    }
01135    AST_RWLIST_UNLOCK(&protos);
01136 
01137    return cur;
01138 }

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

Definition at line 1265 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.

01266 {
01267    switch (cmd) {
01268    case CLI_INIT:
01269       e->command = "udptl set debug {on|off|ip}";
01270       e->usage = 
01271          "Usage: udptl set debug {on|off|ip host[:port]}\n"
01272          "       Enable or disable dumping of UDPTL packets.\n"
01273          "       If ip is specified, limit the dumped packets to those to and from\n"
01274          "       the specified 'host' with optional port.\n";
01275       return NULL;
01276    case CLI_GENERATE:
01277       return NULL;
01278    }
01279 
01280    if (a->argc < 4 || a->argc > 5)
01281       return CLI_SHOWUSAGE;
01282 
01283    if (a->argc == 4) {
01284       if (!strncasecmp(a->argv[3], "on", 2)) {
01285          udptldebug = 1;
01286          memset(&udptldebugaddr, 0, sizeof(udptldebugaddr));
01287          ast_cli(a->fd, "UDPTL Debugging Enabled\n");
01288       } else if (!strncasecmp(a->argv[3], "off", 3)) {
01289          udptldebug = 0;
01290          ast_cli(a->fd, "UDPTL Debugging Disabled\n");
01291       } else {
01292          return CLI_SHOWUSAGE;
01293       }
01294    } else {
01295       struct ast_sockaddr *addrs;
01296       if (strncasecmp(a->argv[3], "ip", 2))
01297          return CLI_SHOWUSAGE;
01298       if (!ast_sockaddr_resolve(&addrs, a->argv[4], 0, 0)) {
01299          return CLI_SHOWUSAGE;
01300       }
01301       ast_sockaddr_copy(&udptldebugaddr, &addrs[0]);
01302          ast_cli(a->fd, "UDPTL Debugging Enabled for IP: %s\n", ast_sockaddr_stringify(&udptldebugaddr));
01303       udptldebug = 1;
01304       ast_free(addrs);
01305    }
01306 
01307    return CLI_SUCCESS;
01308 }

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 526 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().

00527 {
00528    uint8_t fec[LOCAL_FAX_MAX_DATAGRAM * 2] = { 0, };
00529    int i;
00530    int j;
00531    int seq;
00532    int entry;
00533    int entries;
00534    int span;
00535    int m;
00536    unsigned int len;
00537    int limit;
00538    int high_tide;
00539 
00540    seq = s->tx_seq_no & 0xFFFF;
00541 
00542    /* Map the sequence number to an entry in the circular buffer */
00543    entry = seq & UDPTL_BUF_MASK;
00544 
00545    /* We save the message in a circular buffer, for generating FEC or
00546       redundancy sets later on. */
00547    s->tx[entry].buf_len = ifp_len;
00548    memcpy(s->tx[entry].buf, ifp, ifp_len);
00549    
00550    /* Build the UDPTLPacket */
00551 
00552    len = 0;
00553    /* Encode the sequence number */
00554    buf[len++] = (seq >> 8) & 0xFF;
00555    buf[len++] = seq & 0xFF;
00556 
00557    /* Encode the primary IFP packet */
00558    if (encode_open_type(s, buf, buflen, &len, ifp, ifp_len) < 0)
00559       return -1;
00560 
00561    /* Encode the appropriate type of error recovery information */
00562    switch (s->error_correction_scheme)
00563    {
00564    case UDPTL_ERROR_CORRECTION_NONE:
00565       /* Encode the error recovery type */
00566       buf[len++] = 0x00;
00567       /* The number of entries will always be zero, so it is pointless allowing
00568          for the fragmented case here. */
00569       if (encode_length(buf, &len, 0) < 0)
00570          return -1;
00571       break;
00572    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00573       /* Encode the error recovery type */
00574       buf[len++] = 0x00;
00575       if (s->tx_seq_no > s->error_correction_entries)
00576          entries = s->error_correction_entries;
00577       else
00578          entries = s->tx_seq_no;
00579       /* The number of entries will always be small, so it is pointless allowing
00580          for the fragmented case here. */
00581       if (encode_length(buf, &len, entries) < 0)
00582          return -1;
00583       /* Encode the elements */
00584       for (i = 0; i < entries; i++) {
00585          j = (entry - i - 1) & UDPTL_BUF_MASK;
00586          if (encode_open_type(s, buf, buflen, &len, s->tx[j].buf, s->tx[j].buf_len) < 0) {
00587             ast_debug(1, "UDPTL (%s): Encoding failed at i=%d, j=%d\n",
00588                  LOG_TAG(s), i, j);
00589             return -1;
00590          }
00591       }
00592       break;
00593    case UDPTL_ERROR_CORRECTION_FEC:
00594       span = s->error_correction_span;
00595       entries = s->error_correction_entries;
00596       if (seq < s->error_correction_span*s->error_correction_entries) {
00597          /* In the initial stages, wind up the FEC smoothly */
00598          entries = seq/s->error_correction_span;
00599          if (seq < s->error_correction_span)
00600             span = 0;
00601       }
00602       /* Encode the error recovery type */
00603       buf[len++] = 0x80;
00604       /* Span is defined as an inconstrained integer, which it dumb. It will only
00605          ever be a small value. Treat it as such. */
00606       buf[len++] = 1;
00607       buf[len++] = span;
00608       /* The number of entries is defined as a length, but will only ever be a small
00609          value. Treat it as such. */
00610       buf[len++] = entries;
00611       for (m = 0; m < entries; m++) {
00612          /* Make an XOR'ed entry the maximum length */
00613          limit = (entry + m) & UDPTL_BUF_MASK;
00614          high_tide = 0;
00615          for (i = (limit - span*entries) & UDPTL_BUF_MASK; i != limit; i = (i + entries) & UDPTL_BUF_MASK) {
00616             if (high_tide < s->tx[i].buf_len) {
00617                for (j = 0; j < high_tide; j++)
00618                   fec[j] ^= s->tx[i].buf[j];
00619                for ( ; j < s->tx[i].buf_len; j++)
00620                   fec[j] = s->tx[i].buf[j];
00621                high_tide = s->tx[i].buf_len;
00622             } else {
00623                for (j = 0; j < s->tx[i].buf_len; j++)
00624                   fec[j] ^= s->tx[i].buf[j];
00625             }
00626          }
00627          if (encode_open_type(s, buf, buflen, &len, fec, high_tide) < 0)
00628             return -1;
00629       }
00630       break;
00631    }
00632 
00633    s->tx_seq_no++;
00634    return len;
00635 }

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_debug, AST_FRAME_MODEM, AST_LIST_NEXT, AST_MODEM_T38, udptl_fec_rx_buffer_t::buf, udptl_fec_rx_buffer_t::buf_len, ast_frame_subclass::codec, 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, 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    unsigned int ptr; /* an index that keeps track of how much of the UDPTL packet has been processed */
00316    int seq_no;
00317    const uint8_t *ifp = NULL;
00318    const uint8_t *data = NULL;
00319    unsigned int ifp_len = 0;
00320    int repaired[16];
00321    const uint8_t *bufs[ARRAY_LEN(s->f) - 1];
00322    unsigned int lengths[ARRAY_LEN(s->f) - 1];
00323    int span;
00324    int entries;
00325    int ifp_no;
00326 
00327    ptr = 0;
00328    ifp_no = 0;
00329    memset(&s->f[0], 0, sizeof(s->f[0]));
00330 
00331    /* Decode seq_number */
00332    if (ptr + 2 > len)
00333       return -1;
00334    seq_no = (buf[0] << 8) | buf[1];
00335    ptr += 2;
00336 
00337    /* Break out the primary packet */
00338    if ((stat1 = decode_open_type(buf, len, &ptr, &ifp, &ifp_len)) != 0)
00339       return -1;
00340    /* Decode error_recovery */
00341    if (ptr + 1 > len)
00342       return -1;
00343    if ((buf[ptr++] & 0x80) == 0) {
00344       /* Secondary packet mode for error recovery */
00345       if (seq_no > s->rx_seq_no) {
00346          /* We received a later packet than we expected, so we need to check if we can fill in the gap from the
00347             secondary packets. */
00348          int total_count = 0;
00349          do {
00350             unsigned int count;
00351             if ((stat2 = decode_length(buf, len, &ptr, &count)) < 0)
00352                return -1;
00353             for (i = 0; i < count && total_count + i < ARRAY_LEN(bufs); i++) {
00354                if ((stat1 = decode_open_type(buf, len, &ptr, &bufs[total_count + i], &lengths[total_count + i])) != 0) {
00355                   return -1;
00356                }
00357                /* valid secondaries can contain zero-length packets that should be ignored */
00358                if (!bufs[total_count + i] || !lengths[total_count + i]) {
00359                   /* drop the count of items to process and reuse the buffers that were just set */
00360                   i--;
00361                   count--;
00362                }
00363             }
00364             total_count += i;
00365          }
00366          while (stat2 > 0 && total_count < ARRAY_LEN(bufs));
00367          /* Step through in reverse order, so we go oldest to newest */
00368          for (i = total_count; i > 0; i--) {
00369             if (seq_no - i >= s->rx_seq_no) {
00370                /* This one wasn't seen before */
00371                /* Decode the secondary IFP packet */
00372                ast_debug(3, "Recovering lost packet via secondary %d, len %d\n", seq_no - i, lengths[i - 1]);
00373                s->f[ifp_no].frametype = AST_FRAME_MODEM;
00374                s->f[ifp_no].subclass.codec = AST_MODEM_T38;
00375 
00376                s->f[ifp_no].mallocd = 0;
00377                s->f[ifp_no].seqno = seq_no - i;
00378                s->f[ifp_no].datalen = lengths[i - 1];
00379                s->f[ifp_no].data.ptr = (uint8_t *) bufs[i - 1];
00380                s->f[ifp_no].offset = 0;
00381                s->f[ifp_no].src = "UDPTL";
00382                if (ifp_no > 0)
00383                   AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00384                AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00385                ifp_no++;
00386             }
00387          }
00388       }
00389    }
00390    else
00391    {
00392       int j;
00393       int l;
00394       int x;
00395       /* FEC mode for error recovery */
00396       /* Our buffers cannot tolerate overlength IFP packets in FEC mode */
00397       if (ifp_len > LOCAL_FAX_MAX_DATAGRAM)
00398          return -1;
00399       /* Update any missed slots in the buffer */
00400       for ( ; seq_no > s->rx_seq_no; s->rx_seq_no++) {
00401          x = s->rx_seq_no & UDPTL_BUF_MASK;
00402          s->rx[x].buf_len = -1;
00403          s->rx[x].fec_len[0] = 0;
00404          s->rx[x].fec_span = 0;
00405          s->rx[x].fec_entries = 0;
00406       }
00407 
00408       x = seq_no & UDPTL_BUF_MASK;
00409 
00410       memset(repaired, 0, sizeof(repaired));
00411 
00412       /* Save the new IFP packet */
00413       memcpy(s->rx[x].buf, ifp, ifp_len);
00414       s->rx[x].buf_len = ifp_len;
00415       repaired[x] = TRUE;
00416 
00417       /* Decode the FEC packets */
00418       /* The span is defined as an unconstrained integer, but will never be more
00419          than a small value. */
00420       if (ptr + 2 > len)
00421          return -1;
00422       if (buf[ptr++] != 1)
00423          return -1;
00424       span = buf[ptr++];
00425       s->rx[x].fec_span = span;
00426 
00427       /* The number of entries is defined as a length, but will only ever be a small
00428          value. Treat it as such. */
00429       if (ptr + 1 > len)
00430          return -1;
00431       entries = buf[ptr++];
00432       if (entries > MAX_FEC_ENTRIES) {
00433          return -1;
00434       }
00435       s->rx[x].fec_entries = entries;
00436 
00437       /* Decode the elements */
00438       for (i = 0; i < entries; i++) {
00439          if ((stat1 = decode_open_type(buf, len, &ptr, &data, &s->rx[x].fec_len[i])) != 0)
00440             return -1;
00441          if (s->rx[x].fec_len[i] > LOCAL_FAX_MAX_DATAGRAM)
00442             return -1;
00443 
00444          /* Save the new FEC data */
00445          memcpy(s->rx[x].fec[i], data, s->rx[x].fec_len[i]);
00446 #if 0
00447          fprintf(stderr, "FEC: ");
00448          for (j = 0; j < s->rx[x].fec_len[i]; j++)
00449             fprintf(stderr, "%02X ", data[j]);
00450          fprintf(stderr, "\n");
00451 #endif
00452       }
00453 
00454       /* See if we can reconstruct anything which is missing */
00455       /* TODO: this does not comprehensively hunt back and repair everything that is possible */
00456       for (l = x; l != ((x - (16 - span*entries)) & UDPTL_BUF_MASK); l = (l - 1) & UDPTL_BUF_MASK) {
00457          int m;
00458          if (s->rx[l].fec_len[0] <= 0)
00459             continue;
00460          for (m = 0; m < s->rx[l].fec_entries; m++) {
00461             int k;
00462             int which;
00463             int limit = (l + m) & UDPTL_BUF_MASK;
00464             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) {
00465                if (s->rx[k].buf_len <= 0)
00466                   which = (which == -1) ? k : -2;
00467             }
00468             if (which >= 0) {
00469                /* Repairable */
00470                for (j = 0; j < s->rx[l].fec_len[m]; j++) {
00471                   s->rx[which].buf[j] = s->rx[l].fec[m][j];
00472                   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)
00473                      s->rx[which].buf[j] ^= (s->rx[k].buf_len > j) ? s->rx[k].buf[j] : 0;
00474                }
00475                s->rx[which].buf_len = s->rx[l].fec_len[m];
00476                repaired[which] = TRUE;
00477             }
00478          }
00479       }
00480       /* Now play any new packets forwards in time */
00481       for (l = (x + 1) & UDPTL_BUF_MASK, j = seq_no - UDPTL_BUF_MASK; l != x; l = (l + 1) & UDPTL_BUF_MASK, j++) {
00482          if (repaired[l]) {
00483             //fprintf(stderr, "Fixed packet %d, len %d\n", j, l);
00484             s->f[ifp_no].frametype = AST_FRAME_MODEM;
00485             s->f[ifp_no].subclass.codec = AST_MODEM_T38;
00486          
00487             s->f[ifp_no].mallocd = 0;
00488             s->f[ifp_no].seqno = j;
00489             s->f[ifp_no].datalen = s->rx[l].buf_len;
00490             s->f[ifp_no].data.ptr = s->rx[l].buf;
00491             s->f[ifp_no].offset = 0;
00492             s->f[ifp_no].src = "UDPTL";
00493             if (ifp_no > 0)
00494                AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00495             AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00496             ifp_no++;
00497          }
00498       }
00499    }
00500 
00501    /* If packets are received out of sequence, we may have already processed this packet from the error
00502       recovery information in a packet already received. */
00503    if (seq_no >= s->rx_seq_no) {
00504       /* Decode the primary IFP packet */
00505       s->f[ifp_no].frametype = AST_FRAME_MODEM;
00506       s->f[ifp_no].subclass.codec = AST_MODEM_T38;
00507       
00508       s->f[ifp_no].mallocd = 0;
00509       s->f[ifp_no].seqno = seq_no;
00510       s->f[ifp_no].datalen = ifp_len;
00511       s->f[ifp_no].data.ptr = (uint8_t *) ifp;
00512       s->f[ifp_no].offset = 0;
00513       s->f[ifp_no].src = "UDPTL";
00514       if (ifp_no > 0)
00515          AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00516       AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00517 
00518       ifp_no++;
00519    }
00520 
00521    s->rx_seq_no = seq_no + 1;
00522    return ifp_no;
00523 }

static void udptl_shutdown ( void   )  [static]

Definition at line 1425 of file udptl.c.

References ARRAY_LEN, and ast_cli_unregister_multiple().

Referenced by ast_udptl_init().

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

Definition at line 657 of file udptl.c.

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

Referenced by ast_udptl_new_with_bindaddr().

00658 {
00659    struct ast_udptl *udptl = cbdata;
00660    struct ast_frame *f;
00661 
00662    if ((f = ast_udptl_read(udptl))) {
00663       if (udptl->callback)
00664          udptl->callback(udptl, f, udptl->data);
00665    }
00666    return 1;
00667 }


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 1311 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 = 4599 [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 = 4500 [static]

Definition at line 85 of file udptl.c.

int use_even_ports [static]

Definition at line 94 of file udptl.c.


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