Mon Jun 27 16:51:21 2011

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 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)
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)
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)
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 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 94 of file udptl.c.

Referenced by ast_udptl_set_far_max_datagram(), and ast_udptl_write().

#define FALSE   0

Definition at line 74 of file udptl.c.

#define FAX_MAX_DATAGRAM_LIMIT   1400

Definition at line 95 of file udptl.c.

Referenced by ast_udptl_set_far_max_datagram().

#define LOCAL_FAX_MAX_DATAGRAM   1400

Definition at line 93 of file udptl.c.

Referenced by calculate_local_max_datagram(), and udptl_build_packet().

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

Definition at line 80 of file udptl.c.

Referenced by ast_udptl_read(), ast_udptl_write(), calculate_far_max_ifp(), calculate_local_max_datagram(), encode_open_type(), and udptl_build_packet().

#define MAX_FEC_ENTRIES   5

Definition at line 96 of file udptl.c.

Referenced by __ast_udptl_reload().

#define MAX_FEC_SPAN   5

Definition at line 97 of file udptl.c.

Referenced by __ast_udptl_reload().

#define TRUE   (!FALSE)

Definition at line 77 of file udptl.c.

#define UDPTL_BUF_MASK   15

Definition at line 99 of file udptl.c.

#define UDPTL_MTU   1200

Definition at line 71 of file udptl.c.


Function Documentation

static void __ast_udptl_reload ( int  reload  )  [static]

Definition at line 1299 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_flags, 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().

01300 {
01301    struct ast_config *cfg;
01302    const char *s;
01303    struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };
01304 
01305    cfg = ast_config_load2("udptl.conf", "udptl", config_flags);
01306    if (cfg == CONFIG_STATUS_FILEMISSING || cfg == CONFIG_STATUS_FILEUNCHANGED || cfg == CONFIG_STATUS_FILEINVALID) {
01307       return;
01308    }
01309 
01310    udptlstart = 4500;
01311    udptlend = 4999;
01312    udptlfecentries = 0;
01313    udptlfecspan = 0;
01314    use_even_ports = 0;
01315 
01316    if (cfg) {
01317       if ((s = ast_variable_retrieve(cfg, "general", "udptlstart"))) {
01318          udptlstart = atoi(s);
01319          if (udptlstart < 1024) {
01320             ast_log(LOG_WARNING, "Ports under 1024 are not allowed for T.38.\n");
01321             udptlstart = 1024;
01322          }
01323          if (udptlstart > 65535) {
01324             ast_log(LOG_WARNING, "Ports over 65535 are invalid.\n");
01325             udptlstart = 65535;
01326          }
01327       }
01328       if ((s = ast_variable_retrieve(cfg, "general", "udptlend"))) {
01329          udptlend = atoi(s);
01330          if (udptlend < 1024) {
01331             ast_log(LOG_WARNING, "Ports under 1024 are not allowed for T.38.\n");
01332             udptlend = 1024;
01333          }
01334          if (udptlend > 65535) {
01335             ast_log(LOG_WARNING, "Ports over 65535 are invalid.\n");
01336             udptlend = 65535;
01337          }
01338       }
01339       if ((s = ast_variable_retrieve(cfg, "general", "udptlchecksums"))) {
01340 #ifdef SO_NO_CHECK
01341          if (ast_false(s))
01342             nochecksums = 1;
01343          else
01344             nochecksums = 0;
01345 #else
01346          if (ast_false(s))
01347             ast_log(LOG_WARNING, "Disabling UDPTL checksums is not supported on this operating system!\n");
01348 #endif
01349       }
01350       if ((s = ast_variable_retrieve(cfg, "general", "T38FaxUdpEC"))) {
01351          ast_log(LOG_WARNING, "T38FaxUdpEC in udptl.conf is no longer supported; use the t38pt_udptl configuration option in sip.conf instead.\n");
01352       }
01353       if ((s = ast_variable_retrieve(cfg, "general", "T38FaxMaxDatagram"))) {
01354          ast_log(LOG_WARNING, "T38FaxMaxDatagram in udptl.conf is no longer supported; value is now supplied by T.38 applications.\n");
01355       }
01356       if ((s = ast_variable_retrieve(cfg, "general", "UDPTLFECEntries"))) {
01357          udptlfecentries = atoi(s);
01358          if (udptlfecentries < 1) {
01359             ast_log(LOG_WARNING, "Too small UDPTLFECEntries value.  Defaulting to 1.\n");
01360             udptlfecentries = 1;
01361          }
01362          if (udptlfecentries > MAX_FEC_ENTRIES) {
01363             ast_log(LOG_WARNING, "Too large UDPTLFECEntries value.  Defaulting to %d.\n", MAX_FEC_ENTRIES);
01364             udptlfecentries = MAX_FEC_ENTRIES;
01365          }
01366       }
01367       if ((s = ast_variable_retrieve(cfg, "general", "UDPTLFECSpan"))) {
01368          udptlfecspan = atoi(s);
01369          if (udptlfecspan < 1) {
01370             ast_log(LOG_WARNING, "Too small UDPTLFECSpan value.  Defaulting to 1.\n");
01371             udptlfecspan = 1;
01372          }
01373          if (udptlfecspan > MAX_FEC_SPAN) {
01374             ast_log(LOG_WARNING, "Too large UDPTLFECSpan value.  Defaulting to %d.\n", MAX_FEC_SPAN);
01375             udptlfecspan = MAX_FEC_SPAN;
01376          }
01377       }
01378       if ((s = ast_variable_retrieve(cfg, "general", "use_even_ports"))) {
01379          use_even_ports = ast_true(s);
01380       }
01381       ast_config_destroy(cfg);
01382    }
01383    if (udptlstart >= udptlend) {
01384       ast_log(LOG_WARNING, "Unreasonable values for UDPTL start/end ports; defaulting to 4500-4999.\n");
01385       udptlstart = 4500;
01386       udptlend = 4999;
01387    }
01388    if (use_even_ports && (udptlstart & 1)) {
01389       ++udptlstart;
01390       ast_log(LOG_NOTICE, "Odd numbered udptlstart specified but use_even_ports enabled. udptlstart is now %d\n", udptlstart);
01391    }
01392    if (use_even_ports && (udptlend & 1)) {
01393       --udptlend;
01394       ast_log(LOG_NOTICE, "Odd numbered udptlend specified but use_event_ports enabled. udptlend is now %d\n", udptlend);
01395    }
01396    ast_verb(2, "UDPTL allocating from port range %d -> %d\n", udptlstart, udptlend);
01397 }

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 1124 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, get_proto(), ast_udptl_protocol::get_udptl_info, LOG_WARNING, ast_channel::masq, ast_channel::masqr, ast_channel::name, ast_udptl_protocol::set_udptl_peer, t1, and ast_channel::tech_pvt.

01125 {
01126    struct ast_frame *f;
01127    struct ast_channel *who;
01128    struct ast_channel *cs[3];
01129    struct ast_udptl *p0;
01130    struct ast_udptl *p1;
01131    struct ast_udptl_protocol *pr0;
01132    struct ast_udptl_protocol *pr1;
01133    struct ast_sockaddr ac0;
01134    struct ast_sockaddr ac1;
01135    struct ast_sockaddr t0;
01136    struct ast_sockaddr t1;
01137    void *pvt0;
01138    void *pvt1;
01139    int to;
01140    
01141    ast_channel_lock(c0);
01142    while (ast_channel_trylock(c1)) {
01143       ast_channel_unlock(c0);
01144       usleep(1);
01145       ast_channel_lock(c0);
01146    }
01147    pr0 = get_proto(c0);
01148    pr1 = get_proto(c1);
01149    if (!pr0) {
01150       ast_log(LOG_WARNING, "Can't find native functions for channel '%s'\n", c0->name);
01151       ast_channel_unlock(c0);
01152       ast_channel_unlock(c1);
01153       return -1;
01154    }
01155    if (!pr1) {
01156       ast_log(LOG_WARNING, "Can't find native functions for channel '%s'\n", c1->name);
01157       ast_channel_unlock(c0);
01158       ast_channel_unlock(c1);
01159       return -1;
01160    }
01161    pvt0 = c0->tech_pvt;
01162    pvt1 = c1->tech_pvt;
01163    p0 = pr0->get_udptl_info(c0);
01164    p1 = pr1->get_udptl_info(c1);
01165    if (!p0 || !p1) {
01166       /* Somebody doesn't want to play... */
01167       ast_channel_unlock(c0);
01168       ast_channel_unlock(c1);
01169       return -2;
01170    }
01171    if (pr0->set_udptl_peer(c0, p1)) {
01172       ast_log(LOG_WARNING, "Channel '%s' failed to talk to '%s'\n", c0->name, c1->name);
01173       memset(&ac1, 0, sizeof(ac1));
01174    } else {
01175       /* Store UDPTL peer */
01176       ast_udptl_get_peer(p1, &ac1);
01177    }
01178    if (pr1->set_udptl_peer(c1, p0)) {
01179       ast_log(LOG_WARNING, "Channel '%s' failed to talk back to '%s'\n", c1->name, c0->name);
01180       memset(&ac0, 0, sizeof(ac0));
01181    } else {
01182       /* Store UDPTL peer */
01183       ast_udptl_get_peer(p0, &ac0);
01184    }
01185    ast_channel_unlock(c0);
01186    ast_channel_unlock(c1);
01187    cs[0] = c0;
01188    cs[1] = c1;
01189    cs[2] = NULL;
01190    for (;;) {
01191       if ((c0->tech_pvt != pvt0) ||
01192          (c1->tech_pvt != pvt1) ||
01193          (c0->masq || c0->masqr || c1->masq || c1->masqr)) {
01194             ast_debug(1, "Oooh, something is weird, backing out\n");
01195             /* Tell it to try again later */
01196             return -3;
01197       }
01198       to = -1;
01199       ast_udptl_get_peer(p1, &t1);
01200       ast_udptl_get_peer(p0, &t0);
01201       if (ast_sockaddr_cmp(&t1, &ac1)) {
01202          ast_debug(1, "Oooh, '%s' changed end address to %s\n", 
01203             c1->name, ast_sockaddr_stringify(&t1));
01204          ast_debug(1, "Oooh, '%s' was %s\n", 
01205             c1->name, ast_sockaddr_stringify(&ac1));
01206          ast_sockaddr_copy(&ac1, &t1);
01207       }
01208       if (ast_sockaddr_cmp(&t0, &ac0)) {
01209          ast_debug(1, "Oooh, '%s' changed end address to %s\n", 
01210             c0->name, ast_sockaddr_stringify(&t0));
01211          ast_debug(1, "Oooh, '%s' was %s\n", 
01212             c0->name, ast_sockaddr_stringify(&ac0));
01213          ast_sockaddr_copy(&ac0, &t0);
01214       }
01215       who = ast_waitfor_n(cs, 2, &to);
01216       if (!who) {
01217          ast_debug(1, "Ooh, empty read...\n");
01218          /* check for hangup / whentohangup */
01219          if (ast_check_hangup(c0) || ast_check_hangup(c1))
01220             break;
01221          continue;
01222       }
01223       f = ast_read(who);
01224       if (!f) {
01225          *fo = f;
01226          *rc = who;
01227          ast_debug(1, "Oooh, got a %s\n", f ? "digit" : "hangup");
01228          /* That's all we needed */
01229          return 0;
01230       } else {
01231          if (f->frametype == AST_FRAME_MODEM) {
01232             /* Forward T.38 frames if they happen upon us */
01233             if (who == c0) {
01234                ast_write(c1, f);
01235             } else if (who == c1) {
01236                ast_write(c0, f);
01237             }
01238          }
01239          ast_frfree(f);
01240       }
01241       /* Swap priority. Not that it's a big deal at this point */
01242       cs[2] = cs[0];
01243       cs[0] = cs[1];
01244       cs[1] = cs[2];
01245    }
01246    return -1;
01247 }

void ast_udptl_destroy ( struct ast_udptl udptl  ) 

Definition at line 1022 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(), and create_addr_from_peer().

01023 {
01024    if (udptl->ioid)
01025       ast_io_remove(udptl->io, udptl->ioid);
01026    if (udptl->fd > -1)
01027       close(udptl->fd);
01028    if (udptl->tag)
01029       ast_free(udptl->tag);
01030    ast_free(udptl);
01031 }

int ast_udptl_fd ( const struct ast_udptl udptl  ) 

Definition at line 630 of file udptl.c.

References ast_udptl::fd.

Referenced by __oh323_new(), and sip_new().

00631 {
00632    return udptl->fd;
00633 }

enum ast_t38_ec_modes ast_udptl_get_error_correction_scheme ( const struct ast_udptl udptl  ) 

Definition at line 817 of file udptl.c.

References ast_udptl::error_correction_scheme.

Referenced by add_sdp().

00818 {
00819    return udptl->error_correction_scheme;
00820 }

unsigned int ast_udptl_get_far_max_datagram ( const struct ast_udptl udptl  ) 

Definition at line 885 of file udptl.c.

References ast_udptl::far_max_datagram.

Referenced by process_sdp().

00886 {
00887    if (udptl->far_max_datagram < 0) {
00888       return 0;
00889    }
00890    return udptl->far_max_datagram;
00891 }

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 893 of file udptl.c.

References calculate_far_max_ifp(), and ast_udptl::far_max_ifp.

Referenced by change_t38_state(), and interpret_t38_parameters().

00894 {
00895    if (udptl->far_max_ifp == -1) {
00896       calculate_far_max_ifp(udptl);
00897    }
00898 
00899    if (udptl->far_max_ifp < 0) {
00900       return 0;
00901    }
00902    return udptl->far_max_ifp;
00903 }

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 861 of file udptl.c.

References calculate_local_max_datagram(), and ast_udptl::local_max_datagram.

Referenced by add_sdp().

00862 {
00863    if (udptl->local_max_datagram == -1) {
00864       calculate_local_max_datagram(udptl);
00865    }
00866 
00867    /* this function expects a unsigned value in return. */
00868    if (udptl->local_max_datagram < 0) {
00869       return 0;
00870    }
00871    return udptl->local_max_datagram;
00872 }

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

Definition at line 1007 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::them.

Referenced by ast_udptl_bridge(), and sip_set_udptl_peer().

01008 {
01009    ast_sockaddr_copy(them, &udptl->them);
01010 }

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

Definition at line 1012 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::us.

Referenced by add_sdp().

01013 {
01014    ast_sockaddr_copy(us, &udptl->us);
01015 }

void ast_udptl_init ( void   ) 

Definition at line 1405 of file udptl.c.

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

Referenced by main().

01406 {
01407    ast_cli_register_multiple(cli_udptl, ARRAY_LEN(cli_udptl));
01408    __ast_udptl_reload(0);
01409 }

struct ast_udptl* ast_udptl_new_with_bindaddr ( struct sched_context sched,
struct io_context io,
int  callbackmode,
struct ast_sockaddr addr 
)

Definition at line 905 of file udptl.c.

References ast_bind(), ast_calloc, ast_free, ast_log(), ast_random(), ast_sockaddr_copy(), ast_sockaddr_is_ipv6(), ast_sockaddr_set_port, errno, ast_udptl::flags, and LOG_WARNING.

Referenced by create_addr_from_peer(), handle_request_invite(), and sip_alloc().

00906 {
00907    struct ast_udptl *udptl;
00908    int x;
00909    int startplace;
00910    int i;
00911    long int flags;
00912 
00913    if (!(udptl = ast_calloc(1, sizeof(*udptl))))
00914       return NULL;
00915 
00916    udptl->error_correction_span = udptlfecspan;
00917    udptl->error_correction_entries = udptlfecentries;
00918    
00919    udptl->far_max_datagram = -1;
00920    udptl->far_max_ifp = -1;
00921    udptl->local_max_ifp = -1;
00922    udptl->local_max_datagram = -1;
00923 
00924    for (i = 0; i <= UDPTL_BUF_MASK; i++) {
00925       udptl->rx[i].buf_len = -1;
00926       udptl->tx[i].buf_len = -1;
00927    }
00928 
00929    if ((udptl->fd = socket(ast_sockaddr_is_ipv6(addr) ?
00930                AF_INET6 : AF_INET, SOCK_DGRAM, 0)) < 0) {
00931       ast_free(udptl);
00932       ast_log(LOG_WARNING, "Unable to allocate socket: %s\n", strerror(errno));
00933       return NULL;
00934    }
00935    flags = fcntl(udptl->fd, F_GETFL);
00936    fcntl(udptl->fd, F_SETFL, flags | O_NONBLOCK);
00937 #ifdef SO_NO_CHECK
00938    if (nochecksums)
00939       setsockopt(udptl->fd, SOL_SOCKET, SO_NO_CHECK, &nochecksums, sizeof(nochecksums));
00940 #endif
00941    /* Find us a place */
00942    x = (udptlstart == udptlend) ? udptlstart : (ast_random() % (udptlend - udptlstart)) + udptlstart;
00943    if (use_even_ports && (x & 1)) {
00944       ++x;
00945    }
00946    startplace = x;
00947    for (;;) {
00948       ast_sockaddr_copy(&udptl->us, addr);
00949       ast_sockaddr_set_port(&udptl->us, x);
00950       if (ast_bind(udptl->fd, &udptl->us) == 0) {
00951          break;
00952       }
00953       if (errno != EADDRINUSE) {
00954          ast_log(LOG_WARNING, "Unexpected bind error: %s\n", strerror(errno));
00955          close(udptl->fd);
00956          ast_free(udptl);
00957          return NULL;
00958       }
00959       if (use_even_ports) {
00960          x += 2;
00961       } else {
00962          ++x;
00963       }
00964       if (x > udptlend)
00965          x = udptlstart;
00966       if (x == startplace) {
00967          ast_log(LOG_WARNING, "No UDPTL ports remaining\n");
00968          close(udptl->fd);
00969          ast_free(udptl);
00970          return NULL;
00971       }
00972    }
00973    if (io && sched && callbackmode) {
00974       /* Operate this one in a callback mode */
00975       udptl->sched = sched;
00976       udptl->io = io;
00977       udptl->ioid = ast_io_add(udptl->io, udptl->fd, udptlread, AST_IO_IN, udptl);
00978    }
00979    return udptl;
00980 }

int ast_udptl_proto_register ( struct ast_udptl_protocol proto  ) 

Definition at line 1093 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().

01094 {
01095    struct ast_udptl_protocol *cur;
01096 
01097    AST_RWLIST_WRLOCK(&protos);
01098    AST_RWLIST_TRAVERSE(&protos, cur, list) {
01099       if (cur->type == proto->type) {
01100          ast_log(LOG_WARNING, "Tried to register same protocol '%s' twice\n", cur->type);
01101          AST_RWLIST_UNLOCK(&protos);
01102          return -1;
01103       }
01104    }
01105    AST_RWLIST_INSERT_TAIL(&protos, proto, list);
01106    AST_RWLIST_UNLOCK(&protos);
01107    return 0;
01108 }

void ast_udptl_proto_unregister ( struct ast_udptl_protocol proto  ) 

Definition at line 1086 of file udptl.c.

References AST_RWLIST_REMOVE, AST_RWLIST_UNLOCK, and AST_RWLIST_WRLOCK.

Referenced by unload_module().

01087 {
01088    AST_RWLIST_WRLOCK(&protos);
01089    AST_RWLIST_REMOVE(&protos, proto, list);
01090    AST_RWLIST_UNLOCK(&protos);
01091 }

struct ast_frame* ast_udptl_read ( struct ast_udptl udptl  ) 

Definition at line 662 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().

00663 {
00664    int res;
00665    struct ast_sockaddr addr;
00666    uint16_t seqno = 0;
00667    uint16_t *udptlheader;
00668    
00669    /* Cache where the header will go */
00670    res = ast_recvfrom(udptl->fd,
00671          udptl->rawdata + AST_FRIENDLY_OFFSET,
00672          sizeof(udptl->rawdata) - AST_FRIENDLY_OFFSET,
00673          0,
00674          &addr);
00675    udptlheader = (uint16_t *)(udptl->rawdata + AST_FRIENDLY_OFFSET);
00676    if (res < 0) {
00677       if (errno != EAGAIN)
00678          ast_log(LOG_WARNING, "(%s): UDPTL read error: %s\n",
00679             LOG_TAG(udptl), strerror(errno));
00680       ast_assert(errno != EBADF);
00681       return &ast_null_frame;
00682    }
00683 
00684    /* Ignore if the other side hasn't been given an address yet. */
00685    if (ast_sockaddr_isnull(&udptl->them)) {
00686       return &ast_null_frame;
00687    }
00688 
00689    if (udptl->nat) {
00690       /* Send to whoever sent to us */
00691       if (ast_sockaddr_cmp(&udptl->them, &addr)) {
00692          ast_sockaddr_copy(&udptl->them, &addr);
00693          ast_debug(1, "UDPTL NAT (%s): Using address %s\n",
00694               LOG_TAG(udptl), ast_sockaddr_stringify(&udptl->them));
00695       }
00696    }
00697 
00698    if (udptl_debug_test_addr(&addr)) {
00699       ast_verb(1, "UDPTL (%s): packet from %s (type %d, seq %d, len %d)\n",
00700           LOG_TAG(udptl), ast_sockaddr_stringify(&addr), 0, seqno, res);
00701    }
00702    if (udptl_rx_packet(udptl, udptl->rawdata + AST_FRIENDLY_OFFSET, res) < 1)
00703       return &ast_null_frame;
00704 
00705    return &udptl->f[0];
00706 }

int ast_udptl_reload ( void   ) 

Version:
1.6.1 return changed to int

Definition at line 1399 of file udptl.c.

References __ast_udptl_reload().

01400 {
01401    __ast_udptl_reload(1);
01402    return 0;
01403 }

void ast_udptl_set_callback ( struct ast_udptl udptl,
ast_udptl_callback  callback 
)

Definition at line 640 of file udptl.c.

References ast_udptl::callback.

00641 {
00642    udptl->callback = callback;
00643 }

void ast_udptl_set_data ( struct ast_udptl udptl,
void *  data 
)

Definition at line 635 of file udptl.c.

References ast_udptl::data.

00636 {
00637    udptl->data = data;
00638 }

void ast_udptl_set_error_correction_scheme ( struct ast_udptl udptl,
enum ast_t38_ec_modes  ec 
)

Definition at line 822 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().

00823 {
00824    udptl->error_correction_scheme = ec;
00825    switch (ec) {
00826    case UDPTL_ERROR_CORRECTION_FEC:
00827       udptl->error_correction_scheme = UDPTL_ERROR_CORRECTION_FEC;
00828       if (udptl->error_correction_entries == 0) {
00829          udptl->error_correction_entries = 3;
00830       }
00831       if (udptl->error_correction_span == 0) {
00832          udptl->error_correction_span = 3;
00833       }
00834       break;
00835    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00836       udptl->error_correction_scheme = UDPTL_ERROR_CORRECTION_REDUNDANCY;
00837       if (udptl->error_correction_entries == 0) {
00838          udptl->error_correction_entries = 3;
00839       }
00840       break;
00841    default:
00842       /* nothing to do */
00843       break;
00844    };
00845    /* reset calculated values so they'll be computed again */
00846    udptl->local_max_datagram = -1;
00847    udptl->far_max_ifp = -1;
00848 }

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 874 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().

00875 {
00876    if (!max_datagram || (max_datagram > FAX_MAX_DATAGRAM_LIMIT)) {
00877       udptl->far_max_datagram = DEFAULT_FAX_MAX_DATAGRAM;
00878    } else {
00879       udptl->far_max_datagram = max_datagram;
00880    }
00881    /* reset calculated values so they'll be computed again */
00882    udptl->far_max_ifp = -1;
00883 }

void ast_udptl_set_local_max_ifp ( struct ast_udptl udptl,
unsigned int  max_ifp 
)

Definition at line 850 of file udptl.c.

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

Referenced by interpret_t38_parameters().

00851 {
00852    /* make sure max_ifp is a positive value since a cast will take place when
00853     * when setting local_max_ifp */
00854    if ((signed int) max_ifp > 0) {
00855       udptl->local_max_ifp = max_ifp;
00856       /* reset calculated values so they'll be computed again */
00857       udptl->local_max_datagram = -1;
00858    }
00859 }

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

Definition at line 1002 of file udptl.c.

References ast_sockaddr_copy(), and ast_udptl::them.

Referenced by process_sdp().

01003 {
01004    ast_sockaddr_copy(&udptl->them, them);
01005 }

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 982 of file udptl.c.

References ast_free, ast_vasprintf, and ast_udptl::tag.

Referenced by change_t38_state().

00983 {
00984    va_list ap;
00985 
00986    if (udptl->tag) {
00987       ast_free(udptl->tag);
00988       udptl->tag = NULL;
00989    }
00990    va_start(ap, format);
00991    if (ast_vasprintf(&udptl->tag, format, ap) == -1) {
00992       udptl->tag = NULL;
00993    }
00994    va_end(ap);
00995 }

void ast_udptl_setnat ( struct ast_udptl udptl,
int  nat 
)

Definition at line 645 of file udptl.c.

References ast_udptl::nat.

Referenced by do_setnat().

00646 {
00647    udptl->nat = nat;
00648 }

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

Definition at line 997 of file udptl.c.

References ast_netsock_set_qos(), and ast_udptl::fd.

Referenced by sip_alloc().

00998 {
00999    return ast_netsock_set_qos(udptl->fd, tos, cos, "UDPTL");
01000 }

void ast_udptl_stop ( struct ast_udptl udptl  ) 

Definition at line 1017 of file udptl.c.

References ast_sockaddr_setnull(), and ast_udptl::them.

Referenced by process_sdp(), and stop_media_flows().

01018 {
01019    ast_sockaddr_setnull(&udptl->them);
01020 }

int ast_udptl_write ( struct ast_udptl s,
struct ast_frame f 
)

Definition at line 1033 of file udptl.c.

References AST_FRAME_MODEM, ast_log(), AST_MODEM_T38, ast_sendto(), ast_sockaddr_isnull(), ast_sockaddr_stringify(), ast_verb, DEFAULT_FAX_MAX_DATAGRAM, errno, f, ast_udptl::far_max_datagram, ast_udptl::far_max_ifp, ast_udptl::fd, len(), LOG_NOTICE, LOG_TAG, LOG_WARNING, seq, ast_udptl::them, ast_udptl::tx_seq_no, udptl_build_packet(), and udptl_debug_test_addr().

Referenced by sip_write().

01034 {
01035    unsigned int seq;
01036    unsigned int len = f->datalen;
01037    int res;
01038    /* if no max datagram size is provided, use default value */
01039    const int bufsize = (s->far_max_datagram > 0) ? s->far_max_datagram : DEFAULT_FAX_MAX_DATAGRAM;
01040    uint8_t buf[bufsize];
01041 
01042    memset(buf, 0, sizeof(buf));
01043 
01044    /* If we have no peer, return immediately */
01045    if (ast_sockaddr_isnull(&s->them)) {
01046       return 0;
01047    }
01048 
01049    /* If there is no data length, return immediately */
01050    if (f->datalen == 0)
01051       return 0;
01052    
01053    if ((f->frametype != AST_FRAME_MODEM) ||
01054        (f->subclass.codec != AST_MODEM_T38)) {
01055       ast_log(LOG_WARNING, "(%s): UDPTL can only send T.38 data.\n",
01056          LOG_TAG(s));
01057       return -1;
01058    }
01059 
01060    if (len > s->far_max_ifp) {
01061       ast_log(LOG_WARNING,
01062          "(%s): UDPTL asked to send %d bytes of IFP when far end only prepared to accept %d bytes; data loss will occur."
01063          "You may need to override the T38FaxMaxDatagram value for this endpoint in the channel driver configuration.\n",
01064          LOG_TAG(s), len, s->far_max_ifp);
01065       len = s->far_max_ifp;
01066    }
01067 
01068    /* Save seq_no for debug output because udptl_build_packet increments it */
01069    seq = s->tx_seq_no & 0xFFFF;
01070 
01071    /* Cook up the UDPTL packet, with the relevant EC info. */
01072    len = udptl_build_packet(s, buf, sizeof(buf), f->data.ptr, len);
01073 
01074    if ((signed int) len > 0 && !ast_sockaddr_isnull(&s->them)) {
01075       if ((res = ast_sendto(s->fd, buf, len, 0, &s->them)) < 0)
01076          ast_log(LOG_NOTICE, "(%s): UDPTL Transmission error to %s: %s\n",
01077             LOG_TAG(s), ast_sockaddr_stringify(&s->them), strerror(errno));
01078       if (udptl_debug_test_addr(&s->them))
01079          ast_verb(1, "UDPTL (%s): packet to %s (type %d, seq %d, len %d)\n",
01080              LOG_TAG(s), ast_sockaddr_stringify(&s->them), 0, seq, len);
01081    }
01082       
01083    return 0;
01084 }

static void calculate_far_max_ifp ( struct ast_udptl udptl  )  [static]

Definition at line 749 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().

00750 {
00751    unsigned new_max = 0;
00752 
00753    if (udptl->far_max_datagram == -1) {
00754       ast_log(LOG_WARNING, "(%s): Cannot calculate far_max_ifp before far_max_datagram has been set.\n",
00755          LOG_TAG(udptl));
00756       udptl->far_max_ifp = -1;
00757       return;
00758    }
00759 
00760    /* the goal here is to supply the local endpoint (application
00761     * or bridged channel) a maximum IFP value that will allow it
00762     * to effectively and efficiently transfer image data at its
00763     * selected bit rate, taking into account the selected error
00764     * correction mode, but without overrunning the far endpoint's
00765     * datagram buffer. this is complicated by the fact that some
00766     * far endpoints send us bogus (small) max datagram values,
00767     * which would result in either buffer overrun or no error
00768     * correction. we try to accomodate those, but if the supplied
00769     * value is too small to do so, we'll emit warning messages and
00770     * the user will have to use configuration options to override
00771     * the max datagram value supplied by the far endpoint.
00772     */
00773    switch (udptl->error_correction_scheme) {
00774    case UDPTL_ERROR_CORRECTION_NONE:
00775       /* need room for sequence number, length indicator, redundancy
00776        * indicator and following length indicator
00777        */
00778       new_max = udptl->far_max_datagram - 5;
00779       break;
00780    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00781       /* for this case, we'd like to send as many error correction entries
00782        * as possible (up to the number we're configured for), but we'll settle
00783        * for sending fewer if the configured number would cause the
00784        * calculated max IFP to be too small for effective operation
00785        *
00786        * need room for sequence number, length indicators and the
00787        * configured number of redundant packets
00788        *
00789        * note: we purposely don't allow error_correction_entries to drop to
00790        * zero in this loop; we'd rather send smaller IFPs (and thus reduce
00791        * the image data transfer rate) than sacrifice redundancy completely
00792        */
00793       for (;;) {
00794          new_max = (udptl->far_max_datagram - 8) / (udptl->error_correction_entries + 1);
00795 
00796          if ((new_max < 80) && (udptl->error_correction_entries > 1)) {
00797             /* the max ifp is not large enough, subtract an
00798              * error correction entry and calculate again
00799              * */
00800             --udptl->error_correction_entries;
00801          } else {
00802             break;
00803          }
00804       }
00805       break;
00806    case UDPTL_ERROR_CORRECTION_FEC:
00807       /* need room for sequence number, length indicators and a
00808        * a single IFP of the maximum size expected
00809        */
00810       new_max = (udptl->far_max_datagram - 10) / 2;
00811       break;
00812    }
00813    /* subtract 5% of space for insurance */
00814    udptl->far_max_ifp = new_max * 0.95;
00815 }

static void calculate_local_max_datagram ( struct ast_udptl udptl  )  [static]

Definition at line 708 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().

00709 {
00710    unsigned int new_max = 0;
00711 
00712    if (udptl->local_max_ifp == -1) {
00713       ast_log(LOG_WARNING, "(%s): Cannot calculate local_max_datagram before local_max_ifp has been set.\n",
00714          LOG_TAG(udptl));
00715       udptl->local_max_datagram = -1;
00716       return;
00717    }
00718 
00719    /* calculate the amount of space required to receive an IFP
00720     * of the maximum size supported by the application/endpoint
00721     * that we are delivering them to (local endpoint), and add
00722     * the amount of space required to support the selected
00723     * error correction mode
00724     */
00725    switch (udptl->error_correction_scheme) {
00726    case UDPTL_ERROR_CORRECTION_NONE:
00727       /* need room for sequence number, length indicator, redundancy
00728        * indicator and following length indicator
00729        */
00730       new_max = 5 + udptl->local_max_ifp;
00731       break;
00732    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00733       /* need room for sequence number, length indicators, plus
00734        * room for up to 3 redundancy packets
00735        */
00736       new_max = 5 + udptl->local_max_ifp + 2 + (3 * udptl->local_max_ifp);
00737       break;
00738    case UDPTL_ERROR_CORRECTION_FEC:
00739       /* need room for sequence number, length indicators and a
00740        * a single IFP of the maximum size expected
00741        */
00742       new_max = 5 + udptl->local_max_ifp + 4 + udptl->local_max_ifp;
00743       break;
00744    }
00745    /* add 5% extra space for insurance, but no larger than LOCAL_FAX_MAX_DATAGRAM */
00746    udptl->local_max_datagram = MIN(new_max * 1.05, LOCAL_FAX_MAX_DATAGRAM);
00747 }

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

Definition at line 199 of file udptl.c.

References ast_debug.

Referenced by decode_open_type(), and udptl_rx_packet().

00200 {
00201    if (*len >= limit)
00202       return -1;
00203    if ((buf[*len] & 0x80) == 0) {
00204       *pvalue = buf[*len];
00205       (*len)++;
00206       return 0;
00207    }
00208    if ((buf[*len] & 0x40) == 0) {
00209       if (*len == limit - 1)
00210          return -1;
00211       *pvalue = (buf[*len] & 0x3F) << 8;
00212       (*len)++;
00213       *pvalue |= buf[*len];
00214       (*len)++;
00215       return 0;
00216    }
00217    *pvalue = (buf[*len] & 0x3F) << 14;
00218    (*len)++;
00219    /* We have a fragment.  Currently we don't process fragments. */
00220    ast_debug(1, "UDPTL packet with length greater than 16K received, decoding will fail\n");
00221    return 1;
00222 }

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 225 of file udptl.c.

References decode_length().

Referenced by udptl_rx_packet().

00226 {
00227    unsigned int octet_cnt = 0;
00228 
00229    if (decode_length(buf, limit, len, &octet_cnt) != 0)
00230       return -1;
00231 
00232    if (octet_cnt > 0) {
00233       /* Make sure the buffer contains at least the number of bits requested */
00234       if ((*len + octet_cnt) > limit)
00235          return -1;
00236 
00237       *p_num_octets = octet_cnt;
00238       *p_object = &buf[*len];
00239       *len += octet_cnt;
00240    }
00241 
00242    return 0;
00243 }

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

Definition at line 246 of file udptl.c.

Referenced by encode_open_type(), and udptl_build_packet().

00247 {
00248    unsigned int multiplier;
00249 
00250    if (value < 0x80) {
00251       /* 1 octet */
00252       buf[*len] = value;
00253       (*len)++;
00254       return value;
00255    }
00256    if (value < 0x4000) {
00257       /* 2 octets */
00258       /* Set the first bit of the first octet */
00259       buf[*len] = ((0x8000 | value) >> 8) & 0xFF;
00260       (*len)++;
00261       buf[*len] = value & 0xFF;
00262       (*len)++;
00263       return value;
00264    }
00265    /* Fragmentation */
00266    multiplier = (value < 0x10000) ? (value >> 14) : 4;
00267    /* Set the first 2 bits of the octet */
00268    buf[*len] = 0xC0 | multiplier;
00269    (*len)++;
00270    return multiplier << 14;
00271 }

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 274 of file udptl.c.

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

Referenced by udptl_build_packet().

00276 {
00277    unsigned int enclen;
00278    unsigned int octet_idx;
00279    uint8_t zero_byte;
00280 
00281    /* If open type is of zero length, add a single zero byte (10.1) */
00282    if (num_octets == 0) {
00283       zero_byte = 0;
00284       data = &zero_byte;
00285       num_octets = 1;
00286    }
00287    /* Encode the open type */
00288    for (octet_idx = 0; ; num_octets -= enclen, octet_idx += enclen) {
00289       if ((enclen = encode_length(buf, len, num_octets)) < 0)
00290          return -1;
00291       if (enclen + *len > buflen) {
00292          ast_log(LOG_ERROR, "(%s): Buffer overflow detected (%d + %d > %d)\n",
00293             LOG_TAG(udptl), enclen, *len, buflen);
00294          return -1;
00295       }
00296       if (enclen > 0) {
00297          memcpy(&buf[*len], &data[octet_idx], enclen);
00298          *len += enclen;
00299       }
00300       if (enclen >= num_octets)
00301          break;
00302    }
00303 
00304    return 0;
00305 }

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

Definition at line 1110 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().

01111 {
01112    struct ast_udptl_protocol *cur = NULL;
01113 
01114    AST_RWLIST_RDLOCK(&protos);
01115    AST_RWLIST_TRAVERSE(&protos, cur, list) {
01116       if (cur->type == chan->tech->type)
01117          break;
01118    }
01119    AST_RWLIST_UNLOCK(&protos);
01120 
01121    return cur;
01122 }

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

Definition at line 1249 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.

01250 {
01251    switch (cmd) {
01252    case CLI_INIT:
01253       e->command = "udptl set debug {on|off|ip}";
01254       e->usage = 
01255          "Usage: udptl set debug {on|off|ip host[:port]}\n"
01256          "       Enable or disable dumping of UDPTL packets.\n"
01257          "       If ip is specified, limit the dumped packets to those to and from\n"
01258          "       the specified 'host' with optional port.\n";
01259       return NULL;
01260    case CLI_GENERATE:
01261       return NULL;
01262    }
01263 
01264    if (a->argc < 4 || a->argc > 5)
01265       return CLI_SHOWUSAGE;
01266 
01267    if (a->argc == 4) {
01268       if (!strncasecmp(a->argv[3], "on", 2)) {
01269          udptldebug = 1;
01270          memset(&udptldebugaddr, 0, sizeof(udptldebugaddr));
01271          ast_cli(a->fd, "UDPTL Debugging Enabled\n");
01272       } else if (!strncasecmp(a->argv[3], "off", 3)) {
01273          udptldebug = 0;
01274          ast_cli(a->fd, "UDPTL Debugging Disabled\n");
01275       } else {
01276          return CLI_SHOWUSAGE;
01277       }
01278    } else {
01279       struct ast_sockaddr *addrs;
01280       if (strncasecmp(a->argv[3], "ip", 2))
01281          return CLI_SHOWUSAGE;
01282       if (!ast_sockaddr_resolve(&addrs, a->argv[4], 0, 0)) {
01283          return CLI_SHOWUSAGE;
01284       }
01285       ast_sockaddr_copy(&udptldebugaddr, &addrs[0]);
01286          ast_cli(a->fd, "UDPTL Debugging Enabled for IP: %s\n", ast_sockaddr_stringify(&udptldebugaddr));
01287       udptldebug = 1;
01288       ast_free(addrs);
01289    }
01290 
01291    return CLI_SUCCESS;
01292 }

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 519 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_ERROR_CORRECTION_FEC, UDPTL_ERROR_CORRECTION_NONE, and UDPTL_ERROR_CORRECTION_REDUNDANCY.

Referenced by ast_udptl_write().

00520 {
00521    uint8_t fec[LOCAL_FAX_MAX_DATAGRAM * 2];
00522    int i;
00523    int j;
00524    int seq;
00525    int entry;
00526    int entries;
00527    int span;
00528    int m;
00529    unsigned int len;
00530    int limit;
00531    int high_tide;
00532 
00533    seq = s->tx_seq_no & 0xFFFF;
00534 
00535    /* Map the sequence number to an entry in the circular buffer */
00536    entry = seq & UDPTL_BUF_MASK;
00537 
00538    /* We save the message in a circular buffer, for generating FEC or
00539       redundancy sets later on. */
00540    s->tx[entry].buf_len = ifp_len;
00541    memcpy(s->tx[entry].buf, ifp, ifp_len);
00542    
00543    /* Build the UDPTLPacket */
00544 
00545    len = 0;
00546    /* Encode the sequence number */
00547    buf[len++] = (seq >> 8) & 0xFF;
00548    buf[len++] = seq & 0xFF;
00549 
00550    /* Encode the primary IFP packet */
00551    if (encode_open_type(s, buf, buflen, &len, ifp, ifp_len) < 0)
00552       return -1;
00553 
00554    /* Encode the appropriate type of error recovery information */
00555    switch (s->error_correction_scheme)
00556    {
00557    case UDPTL_ERROR_CORRECTION_NONE:
00558       /* Encode the error recovery type */
00559       buf[len++] = 0x00;
00560       /* The number of entries will always be zero, so it is pointless allowing
00561          for the fragmented case here. */
00562       if (encode_length(buf, &len, 0) < 0)
00563          return -1;
00564       break;
00565    case UDPTL_ERROR_CORRECTION_REDUNDANCY:
00566       /* Encode the error recovery type */
00567       buf[len++] = 0x00;
00568       if (s->tx_seq_no > s->error_correction_entries)
00569          entries = s->error_correction_entries;
00570       else
00571          entries = s->tx_seq_no;
00572       /* The number of entries will always be small, so it is pointless allowing
00573          for the fragmented case here. */
00574       if (encode_length(buf, &len, entries) < 0)
00575          return -1;
00576       /* Encode the elements */
00577       for (i = 0; i < entries; i++) {
00578          j = (entry - i - 1) & UDPTL_BUF_MASK;
00579          if (encode_open_type(s, buf, buflen, &len, s->tx[j].buf, s->tx[j].buf_len) < 0) {
00580             ast_debug(1, "(%s): Encoding failed at i=%d, j=%d\n",
00581                  LOG_TAG(s), i, j);
00582             return -1;
00583          }
00584       }
00585       break;
00586    case UDPTL_ERROR_CORRECTION_FEC:
00587       span = s->error_correction_span;
00588       entries = s->error_correction_entries;
00589       if (seq < s->error_correction_span*s->error_correction_entries) {
00590          /* In the initial stages, wind up the FEC smoothly */
00591          entries = seq/s->error_correction_span;
00592          if (seq < s->error_correction_span)
00593             span = 0;
00594       }
00595       /* Encode the error recovery type */
00596       buf[len++] = 0x80;
00597       /* Span is defined as an inconstrained integer, which it dumb. It will only
00598          ever be a small value. Treat it as such. */
00599       buf[len++] = 1;
00600       buf[len++] = span;
00601       /* The number of entries is defined as a length, but will only ever be a small
00602          value. Treat it as such. */
00603       buf[len++] = entries;
00604       for (m = 0; m < entries; m++) {
00605          /* Make an XOR'ed entry the maximum length */
00606          limit = (entry + m) & UDPTL_BUF_MASK;
00607          high_tide = 0;
00608          for (i = (limit - span*entries) & UDPTL_BUF_MASK; i != limit; i = (i + entries) & UDPTL_BUF_MASK) {
00609             if (high_tide < s->tx[i].buf_len) {
00610                for (j = 0; j < high_tide; j++)
00611                   fec[j] ^= s->tx[i].buf[j];
00612                for ( ; j < s->tx[i].buf_len; j++)
00613                   fec[j] = s->tx[i].buf[j];
00614                high_tide = s->tx[i].buf_len;
00615             } else {
00616                for (j = 0; j < s->tx[i].buf_len; j++)
00617                   fec[j] ^= s->tx[i].buf[j];
00618             }
00619          }
00620          if (encode_open_type(s, buf, buflen, &len, fec, high_tide) < 0)
00621             return -1;
00622       }
00623       break;
00624    }
00625 
00626    s->tx_seq_no++;
00627    return len;
00628 }

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

Definition at line 183 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().

00184 {
00185    if (udptldebug == 0)
00186       return 0;
00187 
00188    if (ast_sockaddr_isnull(&udptldebugaddr)) {
00189       return 1;
00190    }
00191 
00192    if (ast_sockaddr_port(&udptldebugaddr)) {
00193       return !ast_sockaddr_cmp(&udptldebugaddr, addr);
00194    } else {
00195       return !ast_sockaddr_cmp_addr(&udptldebugaddr, addr);
00196    }
00197 }

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

Definition at line 308 of file udptl.c.

References ARRAY_LEN, AST_FRAME_MODEM, AST_LIST_NEXT, AST_MODEM_T38, ast_frame_subclass::codec, ast_frame::data, ast_frame::datalen, decode_length(), decode_open_type(), ast_udptl::f, ast_frame::frametype, ast_frame::mallocd, ast_frame::offset, ast_frame::ptr, ast_udptl::rx_seq_no, ast_frame::seqno, ast_frame::src, and ast_frame::subclass.

Referenced by ast_udptl_read().

00309 {
00310    int stat1;
00311    int stat2;
00312    int i;
00313    int j;
00314    int k;
00315    int l;
00316    int m;
00317    int x;
00318    int limit;
00319    int which;
00320    unsigned int ptr;
00321    unsigned int count;
00322    int total_count;
00323    int seq_no;
00324    const uint8_t *ifp;
00325    const uint8_t *data;
00326    unsigned int ifp_len;
00327    int repaired[16];
00328    const uint8_t *bufs[ARRAY_LEN(s->f) - 1];
00329    unsigned int lengths[ARRAY_LEN(s->f) - 1];
00330    int span;
00331    int entries;
00332    int ifp_no;
00333 
00334    ptr = 0;
00335    ifp_no = 0;
00336    memset(&s->f[0], 0, sizeof(s->f[0]));
00337 
00338    /* Decode seq_number */
00339    if (ptr + 2 > len)
00340       return -1;
00341    seq_no = (buf[0] << 8) | buf[1];
00342    ptr += 2;
00343 
00344    /* Break out the primary packet */
00345    if ((stat1 = decode_open_type(buf, len, &ptr, &ifp, &ifp_len)) != 0)
00346       return -1;
00347    /* Decode error_recovery */
00348    if (ptr + 1 > len)
00349       return -1;
00350    if ((buf[ptr++] & 0x80) == 0) {
00351       /* Secondary packet mode for error recovery */
00352       if (seq_no > s->rx_seq_no) {
00353          /* We received a later packet than we expected, so we need to check if we can fill in the gap from the
00354             secondary packets. */
00355          total_count = 0;
00356          do {
00357             if ((stat2 = decode_length(buf, len, &ptr, &count)) < 0)
00358                return -1;
00359             for (i = 0; i < count && total_count + i < ARRAY_LEN(bufs); i++) {
00360                if ((stat1 = decode_open_type(buf, len, &ptr, &bufs[total_count + i], &lengths[total_count + i])) != 0)
00361                   return -1;
00362             }
00363             total_count += i;
00364          }
00365          while (stat2 > 0 && total_count < ARRAY_LEN(bufs));
00366          /* Step through in reverse order, so we go oldest to newest */
00367          for (i = total_count; i > 0; i--) {
00368             if (seq_no - i >= s->rx_seq_no) {
00369                /* This one wasn't seen before */
00370                /* Decode the secondary IFP packet */
00371                //fprintf(stderr, "Secondary %d, len %d\n", seq_no - i, lengths[i - 1]);
00372                s->f[ifp_no].frametype = AST_FRAME_MODEM;
00373                s->f[ifp_no].subclass.codec = AST_MODEM_T38;
00374 
00375                s->f[ifp_no].mallocd = 0;
00376                s->f[ifp_no].seqno = seq_no - i;
00377                s->f[ifp_no].datalen = lengths[i - 1];
00378                s->f[ifp_no].data.ptr = (uint8_t *) bufs[i - 1];
00379                s->f[ifp_no].offset = 0;
00380                s->f[ifp_no].src = "UDPTL";
00381                if (ifp_no > 0)
00382                   AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00383                AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00384                ifp_no++;
00385             }
00386          }
00387       }
00388    }
00389    else
00390    {
00391       /* FEC mode for error recovery */
00392       /* Our buffers cannot tolerate overlength IFP packets in FEC mode */
00393       if (ifp_len > LOCAL_FAX_MAX_DATAGRAM)
00394          return -1;
00395       /* Update any missed slots in the buffer */
00396       for ( ; seq_no > s->rx_seq_no; s->rx_seq_no++) {
00397          x = s->rx_seq_no & UDPTL_BUF_MASK;
00398          s->rx[x].buf_len = -1;
00399          s->rx[x].fec_len[0] = 0;
00400          s->rx[x].fec_span = 0;
00401          s->rx[x].fec_entries = 0;
00402       }
00403 
00404       x = seq_no & UDPTL_BUF_MASK;
00405 
00406       memset(repaired, 0, sizeof(repaired));
00407 
00408       /* Save the new IFP packet */
00409       memcpy(s->rx[x].buf, ifp, ifp_len);
00410       s->rx[x].buf_len = ifp_len;
00411       repaired[x] = TRUE;
00412 
00413       /* Decode the FEC packets */
00414       /* The span is defined as an unconstrained integer, but will never be more
00415          than a small value. */
00416       if (ptr + 2 > len)
00417          return -1;
00418       if (buf[ptr++] != 1)
00419          return -1;
00420       span = buf[ptr++];
00421       s->rx[x].fec_span = span;
00422 
00423       /* The number of entries is defined as a length, but will only ever be a small
00424          value. Treat it as such. */
00425       if (ptr + 1 > len)
00426          return -1;
00427       entries = buf[ptr++];
00428       if (entries > MAX_FEC_ENTRIES) {
00429          return -1;
00430       }
00431       s->rx[x].fec_entries = entries;
00432 
00433       /* Decode the elements */
00434       for (i = 0; i < entries; i++) {
00435          if ((stat1 = decode_open_type(buf, len, &ptr, &data, &s->rx[x].fec_len[i])) != 0)
00436             return -1;
00437          if (s->rx[x].fec_len[i] > LOCAL_FAX_MAX_DATAGRAM)
00438             return -1;
00439 
00440          /* Save the new FEC data */
00441          memcpy(s->rx[x].fec[i], data, s->rx[x].fec_len[i]);
00442 #if 0
00443          fprintf(stderr, "FEC: ");
00444          for (j = 0; j < s->rx[x].fec_len[i]; j++)
00445             fprintf(stderr, "%02X ", data[j]);
00446          fprintf(stderr, "\n");
00447 #endif
00448       }
00449 
00450       /* See if we can reconstruct anything which is missing */
00451       /* TODO: this does not comprehensively hunt back and repair everything that is possible */
00452       for (l = x; l != ((x - (16 - span*entries)) & UDPTL_BUF_MASK); l = (l - 1) & UDPTL_BUF_MASK) {
00453          if (s->rx[l].fec_len[0] <= 0)
00454             continue;
00455          for (m = 0; m < s->rx[l].fec_entries; m++) {
00456             limit = (l + m) & UDPTL_BUF_MASK;
00457             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) {
00458                if (s->rx[k].buf_len <= 0)
00459                   which = (which == -1) ? k : -2;
00460             }
00461             if (which >= 0) {
00462                /* Repairable */
00463                for (j = 0; j < s->rx[l].fec_len[m]; j++) {
00464                   s->rx[which].buf[j] = s->rx[l].fec[m][j];
00465                   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)
00466                      s->rx[which].buf[j] ^= (s->rx[k].buf_len > j) ? s->rx[k].buf[j] : 0;
00467                }
00468                s->rx[which].buf_len = s->rx[l].fec_len[m];
00469                repaired[which] = TRUE;
00470             }
00471          }
00472       }
00473       /* Now play any new packets forwards in time */
00474       for (l = (x + 1) & UDPTL_BUF_MASK, j = seq_no - UDPTL_BUF_MASK; l != x; l = (l + 1) & UDPTL_BUF_MASK, j++) {
00475          if (repaired[l]) {
00476             //fprintf(stderr, "Fixed packet %d, len %d\n", j, l);
00477             s->f[ifp_no].frametype = AST_FRAME_MODEM;
00478             s->f[ifp_no].subclass.codec = AST_MODEM_T38;
00479          
00480             s->f[ifp_no].mallocd = 0;
00481             s->f[ifp_no].seqno = j;
00482             s->f[ifp_no].datalen = s->rx[l].buf_len;
00483             s->f[ifp_no].data.ptr = s->rx[l].buf;
00484             s->f[ifp_no].offset = 0;
00485             s->f[ifp_no].src = "UDPTL";
00486             if (ifp_no > 0)
00487                AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00488             AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00489             ifp_no++;
00490          }
00491       }
00492    }
00493 
00494    /* If packets are received out of sequence, we may have already processed this packet from the error
00495       recovery information in a packet already received. */
00496    if (seq_no >= s->rx_seq_no) {
00497       /* Decode the primary IFP packet */
00498       s->f[ifp_no].frametype = AST_FRAME_MODEM;
00499       s->f[ifp_no].subclass.codec = AST_MODEM_T38;
00500       
00501       s->f[ifp_no].mallocd = 0;
00502       s->f[ifp_no].seqno = seq_no;
00503       s->f[ifp_no].datalen = ifp_len;
00504       s->f[ifp_no].data.ptr = (uint8_t *) ifp;
00505       s->f[ifp_no].offset = 0;
00506       s->f[ifp_no].src = "UDPTL";
00507       if (ifp_no > 0)
00508          AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
00509       AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
00510 
00511       ifp_no++;
00512    }
00513 
00514    s->rx_seq_no = seq_no + 1;
00515    return ifp_no;
00516 }

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

Definition at line 650 of file udptl.c.

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

00651 {
00652    struct ast_udptl *udptl = cbdata;
00653    struct ast_frame *f;
00654 
00655    if ((f = ast_udptl_read(udptl))) {
00656       if (udptl->callback)
00657          udptl->callback(udptl, f, udptl->data);
00658    }
00659    return 1;
00660 }


Variable Documentation

struct ast_cli_entry cli_udptl[] [static]

Initial value:

 {
   { .handler =  handle_cli_udptl_set_debug , .summary =  "Enable/Disable UDPTL debugging" ,__VA_ARGS__ }
}

Definition at line 1295 of file udptl.c.

Referenced by ast_udptl_init().

int udptldebug [static]

Are we debugging?

Definition at line 84 of file udptl.c.

struct ast_sockaddr udptldebugaddr [static]

Debug packets to/from this host

Definition at line 85 of file udptl.c.

Referenced by handle_cli_udptl_set_debug(), and udptl_debug_test_addr().

int udptlend = 4599 [static]

Definition at line 83 of file udptl.c.

int udptlfecentries [static]

Definition at line 89 of file udptl.c.

int udptlfecspan [static]

Definition at line 90 of file udptl.c.

int udptlstart = 4500 [static]

Definition at line 82 of file udptl.c.

int use_even_ports [static]

Definition at line 91 of file udptl.c.


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