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"

Include dependency graph for udptl.c:

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	FALSE   0
#define	LOCAL_FAX_MAX_DATAGRAM   1400
#define	MAX_FEC_ENTRIES   5
#define	MAX_FEC_SPAN   5
#define	TRUE   (!FALSE)
#define	UDPTL_BUF_MASK   15
#define	UDPTL_MTU   1200
Functions
static void	__ast_udptl_reload (int reload)
static void	__fini_protos (void)
static void	__init_protos (void)
int	ast_udptl_bridge (struct ast_channel *c0, struct ast_channel *c1, int flags, struct ast_frame **fo, struct ast_channel **rc)
void	ast_udptl_destroy (struct ast_udptl *udptl)
int	ast_udptl_fd (const struct ast_udptl *udptl)
enum ast_t38_ec_modes	ast_udptl_get_error_correction_scheme (const struct ast_udptl *udptl)
unsigned int	ast_udptl_get_far_max_datagram (const struct ast_udptl *udptl)
unsigned int	ast_udptl_get_far_max_ifp (const struct ast_udptl *udptl)
unsigned int	ast_udptl_get_local_max_datagram (const struct ast_udptl *udptl)
void	ast_udptl_get_peer (const struct ast_udptl *udptl, struct sockaddr_in *them)
void	ast_udptl_get_us (const struct ast_udptl *udptl, struct sockaddr_in *us)
void	ast_udptl_init (void)
struct ast_udptl *	ast_udptl_new (struct sched_context *sched, struct io_context *io, int callbackmode)
struct ast_udptl *	ast_udptl_new_with_bindaddr (struct sched_context *sched, struct io_context *io, int callbackmode, struct in_addr addr)
int	ast_udptl_proto_register (struct ast_udptl_protocol *proto)
void	ast_udptl_proto_unregister (struct ast_udptl_protocol *proto)
struct ast_frame *	ast_udptl_read (struct ast_udptl *udptl)
int	ast_udptl_reload (void)
void	ast_udptl_set_callback (struct ast_udptl *udptl, ast_udptl_callback callback)
void	ast_udptl_set_data (struct ast_udptl *udptl, void *data)
void	ast_udptl_set_error_correction_scheme (struct ast_udptl *udptl, enum ast_t38_ec_modes ec)
void	ast_udptl_set_far_max_datagram (struct ast_udptl *udptl, unsigned int max_datagram)
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 sockaddr_in *them)
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 (uint8_t *buf, unsigned int buflen, unsigned int *len, const uint8_t *data, unsigned int num_octets)
static struct ast_udptl_protocol *	get_proto (struct ast_channel *chan)
static char *	handle_cli_udptl_set_debug (struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
static int	udptl_build_packet (struct ast_udptl *s, uint8_t *buf, unsigned int buflen, uint8_t *ifp, unsigned int ifp_len)
static int	udptl_debug_test_addr (const struct sockaddr_in *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 sockaddr_in	udptldebugaddr
static int	udptlend = 4599
static int	udptlfecentries
static int	udptlfecspan
static int	udptlmaxdatagram
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>

Definition in file udptl.c.

---

Define Documentation

#define FALSE   0

Definition at line 71 of file udptl.c.

#define LOCAL_FAX_MAX_DATAGRAM   1400

Definition at line 89 of file udptl.c.

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

#define MAX_FEC_ENTRIES   5

Definition at line 90 of file udptl.c.

Referenced by __ast_udptl_reload().

#define MAX_FEC_SPAN   5

Definition at line 91 of file udptl.c.

Referenced by __ast_udptl_reload().

#define TRUE   (!FALSE)

Definition at line 74 of file udptl.c.

#define UDPTL_BUF_MASK   15

Definition at line 93 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 68 of file udptl.c.

---

Function Documentation

static void __ast_udptl_reload

(

int

reload

)

[static]

Definition at line 1253 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, LOCAL_FAX_MAX_DATAGRAM, LOG_NOTICE, LOG_WARNING, MAX_FEC_ENTRIES, MAX_FEC_SPAN, and s.

Referenced by ast_udptl_init(), and ast_udptl_reload().

{
   struct ast_config *cfg;
   const char *s;
   struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };

   cfg = ast_config_load2("udptl.conf", "udptl", config_flags);
   if (cfg == CONFIG_STATUS_FILEMISSING || cfg == CONFIG_STATUS_FILEUNCHANGED || cfg == CONFIG_STATUS_FILEINVALID) {
      return;
   }

   udptlstart = 4500;
   udptlend = 4999;
   udptlfecentries = 0;
   udptlfecspan = 0;
   udptlmaxdatagram = 0;
   use_even_ports = 0;

   if (cfg) {
      if ((s = ast_variable_retrieve(cfg, "general", "udptlstart"))) {
         udptlstart = atoi(s);
         if (udptlstart < 1024) {
            ast_log(LOG_WARNING, "Ports under 1024 are not allowed for T.38.\n");
            udptlstart = 1024;
         }
         if (udptlstart > 65535) {
            ast_log(LOG_WARNING, "Ports over 65535 are invalid.\n");
            udptlstart = 65535;
         }
      }
      if ((s = ast_variable_retrieve(cfg, "general", "udptlend"))) {
         udptlend = atoi(s);
         if (udptlend < 1024) {
            ast_log(LOG_WARNING, "Ports under 1024 are not allowed for T.38.\n");
            udptlend = 1024;
         }
         if (udptlend > 65535) {
            ast_log(LOG_WARNING, "Ports over 65535 are invalid.\n");
            udptlend = 65535;
         }
      }
      if ((s = ast_variable_retrieve(cfg, "general", "udptlchecksums"))) {
#ifdef SO_NO_CHECK
         if (ast_false(s))
            nochecksums = 1;
         else
            nochecksums = 0;
#else
         if (ast_false(s))
            ast_log(LOG_WARNING, "Disabling UDPTL checksums is not supported on this operating system!\n");
#endif
      }
      if ((s = ast_variable_retrieve(cfg, "general", "T38FaxUdpEC"))) {
         ast_log(LOG_WARNING, "T38FaxUdpEC in udptl.conf is no longer supported; use the t38pt_udptl configuration option in sip.conf instead.\n");
      }
      if ((s = ast_variable_retrieve(cfg, "general", "T38FaxMaxDatagram"))) {
         udptlmaxdatagram = atoi(s);
         if (udptlmaxdatagram < 100) {
            ast_log(LOG_WARNING, "Too small T38FaxMaxDatagram size.  Defaulting to 100.\n");
            udptlmaxdatagram = 100;
         }
         if (udptlmaxdatagram > LOCAL_FAX_MAX_DATAGRAM) {
            ast_log(LOG_WARNING, "Too large T38FaxMaxDatagram size.  Defaulting to %d.\n", LOCAL_FAX_MAX_DATAGRAM);
            udptlmaxdatagram = LOCAL_FAX_MAX_DATAGRAM;
         }
      }
      if ((s = ast_variable_retrieve(cfg, "general", "UDPTLFECentries"))) {
         udptlfecentries = atoi(s);
         if (udptlfecentries < 1) {
            ast_log(LOG_WARNING, "Too small UDPTLFECentries value.  Defaulting to 1.\n");
            udptlfecentries = 1;
         }
         if (udptlfecentries > MAX_FEC_ENTRIES) {
            ast_log(LOG_WARNING, "Too large UDPTLFECentries value.  Defaulting to %d.\n", MAX_FEC_ENTRIES);
            udptlfecentries = MAX_FEC_ENTRIES;
         }
      }
      if ((s = ast_variable_retrieve(cfg, "general", "UDPTLFECspan"))) {
         udptlfecspan = atoi(s);
         if (udptlfecspan < 1) {
            ast_log(LOG_WARNING, "Too small UDPTLFECspan value.  Defaulting to 1.\n");
            udptlfecspan = 1;
         }
         if (udptlfecspan > MAX_FEC_SPAN) {
            ast_log(LOG_WARNING, "Too large UDPTLFECspan value.  Defaulting to %d.\n", MAX_FEC_SPAN);
            udptlfecspan = MAX_FEC_SPAN;
         }
      }
      if ((s = ast_variable_retrieve(cfg, "general", "use_even_ports"))) {
         use_even_ports = ast_true(s);
      }
      ast_config_destroy(cfg);
   }
   if (udptlstart >= udptlend) {
      ast_log(LOG_WARNING, "Unreasonable values for UDPTL start/end\n");
      udptlstart = 4500;
      udptlend = 4999;
   }
   if (use_even_ports && (udptlstart & 1)) {
      ++udptlstart;
      ast_log(LOG_NOTICE, "Odd numbered udptlstart specified but use_even_ports enabled. udptlstart is now %d\n", udptlstart);
   }
   if (use_even_ports && (udptlend & 1)) {
      --udptlend;
      ast_log(LOG_NOTICE, "Odd numbered udptlend specified but use_event_ports enabled. udptlend is now %d\n", udptlend);
   }
   ast_verb(2, "UDPTL allocating from port range %d -> %d\n", udptlstart, udptlend);
}

static void __fini_protos

(

void

)

[static]

Definition at line 175 of file udptl.c.

{

static void __init_protos

(

void

)

[static]

Definition at line 175 of file udptl.c.

{

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 1061 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_inet_ntoa(), ast_log(), ast_read(), ast_udptl_get_peer(), ast_waitfor_n(), ast_write(), f, ast_frame::frametype, get_proto(), ast_udptl_protocol::get_udptl_info, inaddrcmp(), LOG_WARNING, ast_channel::masq, ast_channel::masqr, ast_channel::name, ast_udptl_protocol::set_udptl_peer, and ast_channel::tech_pvt.

{
   struct ast_frame *f;
   struct ast_channel *who;
   struct ast_channel *cs[3];
   struct ast_udptl *p0;
   struct ast_udptl *p1;
   struct ast_udptl_protocol *pr0;
   struct ast_udptl_protocol *pr1;
   struct sockaddr_in ac0;
   struct sockaddr_in ac1;
   struct sockaddr_in t0;
   struct sockaddr_in t1;
   void *pvt0;
   void *pvt1;
   int to;
   
   ast_channel_lock(c0);
   while (ast_channel_trylock(c1)) {
      ast_channel_unlock(c0);
      usleep(1);
      ast_channel_lock(c0);
   }
   pr0 = get_proto(c0);
   pr1 = get_proto(c1);
   if (!pr0) {
      ast_log(LOG_WARNING, "Can't find native functions for channel '%s'\n", c0->name);
      ast_channel_unlock(c0);
      ast_channel_unlock(c1);
      return -1;
   }
   if (!pr1) {
      ast_log(LOG_WARNING, "Can't find native functions for channel '%s'\n", c1->name);
      ast_channel_unlock(c0);
      ast_channel_unlock(c1);
      return -1;
   }
   pvt0 = c0->tech_pvt;
   pvt1 = c1->tech_pvt;
   p0 = pr0->get_udptl_info(c0);
   p1 = pr1->get_udptl_info(c1);
   if (!p0 || !p1) {
      /* Somebody doesn't want to play... */
      ast_channel_unlock(c0);
      ast_channel_unlock(c1);
      return -2;
   }
   if (pr0->set_udptl_peer(c0, p1)) {
      ast_log(LOG_WARNING, "Channel '%s' failed to talk to '%s'\n", c0->name, c1->name);
      memset(&ac1, 0, sizeof(ac1));
   } else {
      /* Store UDPTL peer */
      ast_udptl_get_peer(p1, &ac1);
   }
   if (pr1->set_udptl_peer(c1, p0)) {
      ast_log(LOG_WARNING, "Channel '%s' failed to talk back to '%s'\n", c1->name, c0->name);
      memset(&ac0, 0, sizeof(ac0));
   } else {
      /* Store UDPTL peer */
      ast_udptl_get_peer(p0, &ac0);
   }
   ast_channel_unlock(c0);
   ast_channel_unlock(c1);
   cs[0] = c0;
   cs[1] = c1;
   cs[2] = NULL;
   for (;;) {
      if ((c0->tech_pvt != pvt0) ||
         (c1->tech_pvt != pvt1) ||
         (c0->masq || c0->masqr || c1->masq || c1->masqr)) {
            ast_debug(1, "Oooh, something is weird, backing out\n");
            /* Tell it to try again later */
            return -3;
      }
      to = -1;
      ast_udptl_get_peer(p1, &t1);
      ast_udptl_get_peer(p0, &t0);
      if (inaddrcmp(&t1, &ac1)) {
         ast_debug(1, "Oooh, '%s' changed end address to %s:%d\n", 
            c1->name, ast_inet_ntoa(t1.sin_addr), ntohs(t1.sin_port));
         ast_debug(1, "Oooh, '%s' was %s:%d\n", 
            c1->name, ast_inet_ntoa(ac1.sin_addr), ntohs(ac1.sin_port));
         memcpy(&ac1, &t1, sizeof(ac1));
      }
      if (inaddrcmp(&t0, &ac0)) {
         ast_debug(1, "Oooh, '%s' changed end address to %s:%d\n", 
            c0->name, ast_inet_ntoa(t0.sin_addr), ntohs(t0.sin_port));
         ast_debug(1, "Oooh, '%s' was %s:%d\n", 
            c0->name, ast_inet_ntoa(ac0.sin_addr), ntohs(ac0.sin_port));
         memcpy(&ac0, &t0, sizeof(ac0));
      }
      who = ast_waitfor_n(cs, 2, &to);
      if (!who) {
         ast_debug(1, "Ooh, empty read...\n");
         /* check for hangup / whentohangup */
         if (ast_check_hangup(c0) || ast_check_hangup(c1))
            break;
         continue;
      }
      f = ast_read(who);
      if (!f) {
         *fo = f;
         *rc = who;
         ast_debug(1, "Oooh, got a %s\n", f ? "digit" : "hangup");
         /* That's all we needed */
         return 0;
      } else {
         if (f->frametype == AST_FRAME_MODEM) {
            /* Forward T.38 frames if they happen upon us */
            if (who == c0) {
               ast_write(c1, f);
            } else if (who == c1) {
               ast_write(c0, f);
            }
         }
         ast_frfree(f);
      }
      /* Swap priority. Not that it's a big deal at this point */
      cs[2] = cs[0];
      cs[0] = cs[1];
      cs[1] = cs[2];
   }
   return -1;
}

void ast_udptl_destroy

(

struct ast_udptl *

udptl

)

Definition at line 966 of file udptl.c.

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

Referenced by __sip_destroy(), and create_addr_from_peer().

{
   if (udptl->ioid)
      ast_io_remove(udptl->io, udptl->ioid);
   if (udptl->fd > -1)
      close(udptl->fd);
   ast_free(udptl);
}

int ast_udptl_fd

(

const struct ast_udptl *

udptl

)

Definition at line 629 of file udptl.c.

References ast_udptl::fd.

Referenced by __oh323_new(), and sip_new().

{
   return udptl->fd;
}

enum ast_t38_ec_modes ast_udptl_get_error_correction_scheme

(

const struct ast_udptl *

udptl

)

Definition at line 772 of file udptl.c.

References ast_log(), ast_udptl::error_correction_scheme, and LOG_WARNING.

Referenced by add_sdp().

{
   if (udptl)
      return udptl->error_correction_scheme;
   else {
      ast_log(LOG_WARNING, "udptl structure is null\n");
      return -1;
   }
}

unsigned int ast_udptl_get_far_max_datagram

(

const struct ast_udptl *

udptl

)

Definition at line 822 of file udptl.c.

References ast_log(), ast_udptl::far_max_datagram, and LOG_WARNING.

{
   if (udptl)
      return udptl->far_max_datagram;
   else {
      ast_log(LOG_WARNING, "udptl structure is null\n");
      return 0;
   }
}

unsigned int ast_udptl_get_far_max_ifp

(

const struct ast_udptl *

udptl

)

Definition at line 848 of file udptl.c.

References ast_udptl::far_max_ifp.

Referenced by change_t38_state().

{
   return udptl->far_max_ifp;
}

unsigned int ast_udptl_get_local_max_datagram

(

const struct ast_udptl *

udptl

)

Definition at line 812 of file udptl.c.

References ast_log(), ast_udptl::local_max_datagram, and LOG_WARNING.

Referenced by add_sdp().

{
   if (udptl)
      return udptl->local_max_datagram;
   else {
      ast_log(LOG_WARNING, "udptl structure is null\n");
      return 0;
   }
}

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

Definition at line 947 of file udptl.c.

References ast_udptl::them.

Referenced by ast_udptl_bridge(), and sip_set_udptl_peer().

{
   memset(them, 0, sizeof(*them));
   them->sin_family = AF_INET;
   them->sin_port = udptl->them.sin_port;
   them->sin_addr = udptl->them.sin_addr;
}

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

Definition at line 955 of file udptl.c.

References ast_udptl::us.

Referenced by add_sdp().

{
   memcpy(us, &udptl->us, sizeof(udptl->us));
}

void ast_udptl_init

(

void

)

Definition at line 1368 of file udptl.c.

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

Referenced by main().

{
   ast_cli_register_multiple(cli_udptl, ARRAY_LEN(cli_udptl));
   __ast_udptl_reload(0);
}

struct ast_udptl* ast_udptl_new	(	struct sched_context *	sched,
		struct io_context *	io,
		int	callbackmode
	)			[read]

Definition at line 929 of file udptl.c.

References ast_udptl_new_with_bindaddr().

{
   struct in_addr ia;
   memset(&ia, 0, sizeof(ia));
   return ast_udptl_new_with_bindaddr(sched, io, callbackmode, ia);
}

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

Definition at line 853 of file udptl.c.

References ast_calloc, ast_free, ast_io_add(), AST_IO_IN, ast_log(), ast_random(), 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::fd, ast_udptl::flags, ast_udptl::io, ast_udptl::ioid, ast_udptl::local_max_datagram, LOG_WARNING, ast_udptl::rx, ast_udptl::sched, ast_udptl::them, ast_udptl::tx, UDPTL_BUF_MASK, udptlread(), and ast_udptl::us.

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

{
   struct ast_udptl *udptl;
   int x;
   int startplace;
   int i;
   long int flags;

   if (!(udptl = ast_calloc(1, sizeof(*udptl))))
      return NULL;

   udptl->error_correction_span = udptlfecspan;
   udptl->error_correction_entries = udptlfecentries;
   
   udptl->far_max_datagram = udptlmaxdatagram;
   udptl->local_max_datagram = udptlmaxdatagram;

   for (i = 0; i <= UDPTL_BUF_MASK; i++) {
      udptl->rx[i].buf_len = -1;
      udptl->tx[i].buf_len = -1;
   }

   udptl->them.sin_family = AF_INET;
   udptl->us.sin_family = AF_INET;

   if ((udptl->fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
      ast_free(udptl);
      ast_log(LOG_WARNING, "Unable to allocate socket: %s\n", strerror(errno));
      return NULL;
   }
   flags = fcntl(udptl->fd, F_GETFL);
   fcntl(udptl->fd, F_SETFL, flags | O_NONBLOCK);
#ifdef SO_NO_CHECK
   if (nochecksums)
      setsockopt(udptl->fd, SOL_SOCKET, SO_NO_CHECK, &nochecksums, sizeof(nochecksums));
#endif
   /* Find us a place */
   x = (udptlstart == udptlend) ? udptlstart : (ast_random() % (udptlend - udptlstart)) + udptlstart;
   if (use_even_ports && (x & 1)) {
      ++x;
   }
   startplace = x;
   for (;;) {
      udptl->us.sin_port = htons(x);
      udptl->us.sin_addr = addr;
      if (bind(udptl->fd, (struct sockaddr *) &udptl->us, sizeof(udptl->us)) == 0)
         break;
      if (errno != EADDRINUSE) {
         ast_log(LOG_WARNING, "Unexpected bind error: %s\n", strerror(errno));
         close(udptl->fd);
         ast_free(udptl);
         return NULL;
      }
      if (use_even_ports) {
         x += 2;
      } else {
         ++x;
      }
      if (x > udptlend)
         x = udptlstart;
      if (x == startplace) {
         ast_log(LOG_WARNING, "No UDPTL ports remaining\n");
         close(udptl->fd);
         ast_free(udptl);
         return NULL;
      }
   }
   if (io && sched && callbackmode) {
      /* Operate this one in a callback mode */
      udptl->sched = sched;
      udptl->io = io;
      udptl->ioid = ast_io_add(udptl->io, udptl->fd, udptlread, AST_IO_IN, udptl);
   }
   return udptl;
}

int ast_udptl_proto_register

(

struct ast_udptl_protocol *

proto

)

Definition at line 1030 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().

{
   struct ast_udptl_protocol *cur;

   AST_RWLIST_WRLOCK(&protos);
   AST_RWLIST_TRAVERSE(&protos, cur, list) {
      if (cur->type == proto->type) {
         ast_log(LOG_WARNING, "Tried to register same protocol '%s' twice\n", cur->type);
         AST_RWLIST_UNLOCK(&protos);
         return -1;
      }
   }
   AST_RWLIST_INSERT_TAIL(&protos, proto, list);
   AST_RWLIST_UNLOCK(&protos);
   return 0;
}

void ast_udptl_proto_unregister

(

struct ast_udptl_protocol *

proto

)

Definition at line 1023 of file udptl.c.

References AST_RWLIST_REMOVE, AST_RWLIST_UNLOCK, and AST_RWLIST_WRLOCK.

Referenced by unload_module().

{
   AST_RWLIST_WRLOCK(&protos);
   AST_RWLIST_REMOVE(&protos, proto, list);
   AST_RWLIST_UNLOCK(&protos);
}

struct ast_frame* ast_udptl_read

(

struct ast_udptl *

udptl

)

[read]

Definition at line 661 of file udptl.c.

References ast_assert, ast_debug, AST_FRIENDLY_OFFSET, ast_inet_ntoa(), ast_log(), ast_null_frame, ast_verb, errno, ast_udptl::f, ast_udptl::fd, len(), 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().

{
   int res;
   struct sockaddr_in sin;
   socklen_t len;
   uint16_t seqno = 0;
   uint16_t *udptlheader;

   len = sizeof(sin);
   
   /* Cache where the header will go */
   res = recvfrom(udptl->fd,
         udptl->rawdata + AST_FRIENDLY_OFFSET,
         sizeof(udptl->rawdata) - AST_FRIENDLY_OFFSET,
         0,
         (struct sockaddr *) &sin,
         &len);
   udptlheader = (uint16_t *)(udptl->rawdata + AST_FRIENDLY_OFFSET);
   if (res < 0) {
      if (errno != EAGAIN)
         ast_log(LOG_WARNING, "UDPTL read error: %s\n", strerror(errno));
      ast_assert(errno != EBADF);
      return &ast_null_frame;
   }

   /* Ignore if the other side hasn't been given an address yet. */
   if (!udptl->them.sin_addr.s_addr || !udptl->them.sin_port)
      return &ast_null_frame;

   if (udptl->nat) {
      /* Send to whoever sent to us */
      if ((udptl->them.sin_addr.s_addr != sin.sin_addr.s_addr) ||
         (udptl->them.sin_port != sin.sin_port)) {
         memcpy(&udptl->them, &sin, sizeof(udptl->them));
         ast_debug(1, "UDPTL NAT: Using address %s:%d\n", ast_inet_ntoa(udptl->them.sin_addr), ntohs(udptl->them.sin_port));
      }
   }

   if (udptl_debug_test_addr(&sin)) {
      ast_verb(1, "Got UDPTL packet from %s:%d (type %d, seq %d, len %d)\n",
            ast_inet_ntoa(sin.sin_addr), ntohs(sin.sin_port), 0, seqno, res);
   }
#if 0
   printf("Got UDPTL packet from %s:%d (seq %d, len = %d)\n", ast_inet_ntoa(sin.sin_addr), ntohs(sin.sin_port), seqno, res);
#endif
   if (udptl_rx_packet(udptl, udptl->rawdata + AST_FRIENDLY_OFFSET, res) < 1)
      return &ast_null_frame;

   return &udptl->f[0];
}

int ast_udptl_reload

(

void

)

Version:

1.6.1 return changed to int

Definition at line 1362 of file udptl.c.

References __ast_udptl_reload().

{
   __ast_udptl_reload(1);
   return 0;
}

void ast_udptl_set_callback	(	struct ast_udptl *	udptl,
		ast_udptl_callback	callback
	)

Definition at line 639 of file udptl.c.

References ast_udptl::callback.

{
   udptl->callback = callback;
}

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

Definition at line 634 of file udptl.c.

References ast_udptl::data.

{
   udptl->data = data;
}

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

Definition at line 782 of file udptl.c.

References ast_log(), calculate_far_max_ifp(), calculate_local_max_datagram(), ast_udptl::error_correction_entries, ast_udptl::error_correction_scheme, ast_udptl::error_correction_span, LOG_WARNING, UDPTL_ERROR_CORRECTION_FEC, and UDPTL_ERROR_CORRECTION_REDUNDANCY.

Referenced by process_sdp(), and set_t38_capabilities().

{
   if (udptl) {
      udptl->error_correction_scheme = ec;
      switch (ec) {
      case UDPTL_ERROR_CORRECTION_FEC:
         udptl->error_correction_scheme = UDPTL_ERROR_CORRECTION_FEC;
         if (udptl->error_correction_entries == 0) {
            udptl->error_correction_entries = 3;
         }
         if (udptl->error_correction_span == 0) {
            udptl->error_correction_span = 3;
         }
         break;
      case UDPTL_ERROR_CORRECTION_REDUNDANCY:
         udptl->error_correction_scheme = UDPTL_ERROR_CORRECTION_REDUNDANCY;
         if (udptl->error_correction_entries == 0) {
            udptl->error_correction_entries = 3;
         }
         break;
      default:
         /* nothing to do */
         break;
      };
      calculate_local_max_datagram(udptl);
      calculate_far_max_ifp(udptl);
   } else
      ast_log(LOG_WARNING, "udptl structure is null\n");
}

void ast_udptl_set_far_max_datagram	(	struct ast_udptl *	udptl,
		unsigned int	max_datagram
	)

Definition at line 832 of file udptl.c.

References ast_log(), calculate_far_max_ifp(), ast_udptl::far_max_datagram, and LOG_WARNING.

Referenced by process_sdp().

{
   if (udptl) {
      udptl->far_max_datagram = max_datagram;
      calculate_far_max_ifp(udptl);
   } else {
      ast_log(LOG_WARNING, "udptl structure is null\n");
   }
}

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

Definition at line 842 of file udptl.c.

References calculate_local_max_datagram(), and ast_udptl::local_max_ifp.

Referenced by interpret_t38_parameters().

{
   udptl->local_max_ifp = max_ifp;
   calculate_local_max_datagram(udptl);
}

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

Definition at line 941 of file udptl.c.

References ast_udptl::them.

Referenced by process_sdp().

{
   udptl->them.sin_port = them->sin_port;
   udptl->them.sin_addr = them->sin_addr;
}

void ast_udptl_setnat	(	struct ast_udptl *	udptl,
		int	nat
	)

Definition at line 644 of file udptl.c.

References ast_udptl::nat.

Referenced by do_setnat().

{
   udptl->nat = nat;
}

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

Definition at line 936 of file udptl.c.

References ast_netsock_set_qos(), and ast_udptl::fd.

Referenced by sip_alloc().

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

void ast_udptl_stop

(

struct ast_udptl *

udptl

)

Definition at line 960 of file udptl.c.

References ast_udptl::them.

Referenced by process_sdp(), and stop_media_flows().

{
   memset(&udptl->them.sin_addr, 0, sizeof(udptl->them.sin_addr));
   memset(&udptl->them.sin_port, 0, sizeof(udptl->them.sin_port));
}

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

Definition at line 975 of file udptl.c.

References AST_FRAME_MODEM, ast_inet_ntoa(), ast_log(), AST_MODEM_T38, ast_verb, buf, ast_frame::data, ast_frame::datalen, errno, ast_udptl::far_max_datagram, ast_udptl::far_max_ifp, ast_udptl::fd, ast_frame::frametype, len(), LOG_NOTICE, 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().

{
   unsigned int seq;
   unsigned int len;
   int res;
   uint8_t buf[s->far_max_datagram];

   /* If we have no peer, return immediately */ 
   if (s->them.sin_addr.s_addr == INADDR_ANY)
      return 0;

   /* If there is no data length, return immediately */
   if (f->datalen == 0)
      return 0;
   
   if ((f->frametype != AST_FRAME_MODEM) ||
       (f->subclass != AST_MODEM_T38)) {
      ast_log(LOG_WARNING, "UDPTL can only send T.38 data.\n");
      return -1;
   }

   if (f->datalen > s->far_max_ifp) {
      ast_log(LOG_WARNING,
         "UDPTL asked to send %d bytes of IFP when far end only prepared to accept %d bytes; data loss may occur. "
         "You may need to override the T38FaxMaxDatagram value for this endpoint in the channel driver configuration.\n", f->datalen, s->far_max_ifp);
   }

   /* Save seq_no for debug output because udptl_build_packet increments it */
   seq = s->tx_seq_no & 0xFFFF;

   /* Cook up the UDPTL packet, with the relevant EC info. */
   len = udptl_build_packet(s, buf, sizeof(buf), f->data.ptr, f->datalen);

   if (len > 0 && s->them.sin_port && s->them.sin_addr.s_addr) {
      if ((res = sendto(s->fd, buf, len, 0, (struct sockaddr *) &s->them, sizeof(s->them))) < 0)
         ast_log(LOG_NOTICE, "UDPTL Transmission error to %s:%d: %s\n", ast_inet_ntoa(s->them.sin_addr), ntohs(s->them.sin_port), strerror(errno));
#if 0
      printf("Sent %d bytes of UDPTL data to %s:%d\n", res, ast_inet_ntoa(udptl->them.sin_addr), ntohs(udptl->them.sin_port));
#endif
      if (udptl_debug_test_addr(&s->them))
         ast_verb(1, "Sent UDPTL packet to %s:%d (type %d, seq %d, len %d)\n",
               ast_inet_ntoa(s->them.sin_addr),
               ntohs(s->them.sin_port), 0, seq, len);
   }
      
   return 0;
}

static void calculate_far_max_ifp

(

struct ast_udptl *

udptl

)

[static]

Definition at line 742 of file udptl.c.

References ast_udptl::error_correction_entries, ast_udptl::error_correction_scheme, ast_udptl::far_max_datagram, ast_udptl::far_max_ifp, UDPTL_ERROR_CORRECTION_FEC, UDPTL_ERROR_CORRECTION_NONE, and UDPTL_ERROR_CORRECTION_REDUNDANCY.

Referenced by ast_udptl_set_error_correction_scheme(), and ast_udptl_set_far_max_datagram().

{
   unsigned new_max = 0;

   /* calculate the maximum IFP the local endpoint should
    * generate based on the far end's maximum datagram size
    * and the current error correction mode.
    */
   switch (udptl->error_correction_scheme) {
   case UDPTL_ERROR_CORRECTION_NONE:
      /* only need room for sequence number and length indicators */
      new_max = udptl->far_max_datagram - 6;
      break;
   case UDPTL_ERROR_CORRECTION_REDUNDANCY:
      /* need room for sequence number, length indicators and the
       * configured number of redundant packets
       */
      new_max = (udptl->far_max_datagram - 8) / (udptl->error_correction_entries + 1);
      break;
   case UDPTL_ERROR_CORRECTION_FEC:
      /* need room for sequence number, length indicators and a
       * a single IFP of the maximum size expected
       */
      new_max = (udptl->far_max_datagram - 10) / 2;
      break;
   }
   /* subtract 25% of space for insurance */
   udptl->far_max_ifp = new_max * 0.75;
}

static void calculate_local_max_datagram

(

struct ast_udptl *

udptl

)

[static]

Definition at line 712 of file udptl.c.

References ast_udptl::error_correction_entries, ast_udptl::error_correction_scheme, LOCAL_FAX_MAX_DATAGRAM, ast_udptl::local_max_datagram, ast_udptl::local_max_ifp, MIN, UDPTL_ERROR_CORRECTION_FEC, UDPTL_ERROR_CORRECTION_NONE, and UDPTL_ERROR_CORRECTION_REDUNDANCY.

Referenced by ast_udptl_set_error_correction_scheme(), and ast_udptl_set_local_max_ifp().

{
   unsigned int new_max = 0;

   /* calculate the amount of space required to receive an IFP
    * using the current error correction mode, and ensure that our
    * local max datagram size is at least that big
    */
   switch (udptl->error_correction_scheme) {
   case UDPTL_ERROR_CORRECTION_NONE:
      /* only need room for sequence number and length indicators */
      new_max = 6 + udptl->local_max_ifp;
      break;
   case UDPTL_ERROR_CORRECTION_REDUNDANCY:
      /* need room for sequence number, length indicators and the
       * configured number of redundant packets
       */
      new_max = 6 + udptl->local_max_ifp + 2 + (udptl->error_correction_entries * udptl->local_max_ifp);
      break;
   case UDPTL_ERROR_CORRECTION_FEC:
      /* need room for sequence number, length indicators and a
       * a single IFP of the maximum size expected
       */
      new_max = 6 + udptl->local_max_ifp + 4 + udptl->local_max_ifp;
      break;
   }
   /* add 25% of extra space for insurance, but no larger than LOCAL_FAX_MAX_DATAGRAM */
   udptl->local_max_datagram = MIN(new_max * 1.25, LOCAL_FAX_MAX_DATAGRAM);
}

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

Definition at line 190 of file udptl.c.

Referenced by decode_open_type(), and udptl_rx_packet().

{
   if (*len >= limit)
      return -1;
   if ((buf[*len] & 0x80) == 0) {
      *pvalue = buf[*len];
      (*len)++;
      return 0;
   }
   if ((buf[*len] & 0x40) == 0) {
      if (*len == limit - 1)
         return -1;
      *pvalue = (buf[*len] & 0x3F) << 8;
      (*len)++;
      *pvalue |= buf[*len];
      (*len)++;
      return 0;
   }
   *pvalue = (buf[*len] & 0x3F) << 14;
   (*len)++;
   /* Indicate we have a fragment */
   return 1;
}

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 215 of file udptl.c.

References decode_length().

Referenced by udptl_rx_packet().

{
   unsigned int octet_cnt;
   unsigned int octet_idx;
   unsigned int length;
   unsigned int i;
   const uint8_t **pbuf;

   for (octet_idx = 0, *p_num_octets = 0; ; octet_idx += octet_cnt) {
      octet_cnt = 0;
      if ((length = decode_length(buf, limit, len, &octet_cnt)) < 0)
         return -1;
      if (octet_cnt > 0) {
         *p_num_octets += octet_cnt;

         pbuf = &p_object[octet_idx];
         i = 0;
         /* Make sure the buffer contains at least the number of bits requested */
         if ((*len + octet_cnt) > limit)
            return -1;

         *pbuf = &buf[*len];
         *len += octet_cnt;
      }
      if (length == 0)
         break;
   }
   return 0;
}

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().

{
   unsigned int multiplier;

   if (value < 0x80) {
      /* 1 octet */
      buf[*len] = value;
      (*len)++;
      return value;
   }
   if (value < 0x4000) {
      /* 2 octets */
      /* Set the first bit of the first octet */
      buf[*len] = ((0x8000 | value) >> 8) & 0xFF;
      (*len)++;
      buf[*len] = value & 0xFF;
      (*len)++;
      return value;
   }
   /* Fragmentation */
   multiplier = (value < 0x10000) ? (value >> 14) : 4;
   /* Set the first 2 bits of the octet */
   buf[*len] = 0xC0 | multiplier;
   (*len)++;
   return multiplier << 14;
}

static int encode_open_type	(	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(), and LOG_ERROR.

Referenced by udptl_build_packet().

{
   unsigned int enclen;
   unsigned int octet_idx;
   uint8_t zero_byte;

   /* If open type is of zero length, add a single zero byte (10.1) */
   if (num_octets == 0) {
      zero_byte = 0;
      data = &zero_byte;
      num_octets = 1;
   }
   /* Encode the open type */
   for (octet_idx = 0; ; num_octets -= enclen, octet_idx += enclen) {
      if ((enclen = encode_length(buf, len, num_octets)) < 0)
         return -1;
      if (enclen + *len > buflen) {
         ast_log(LOG_ERROR, "Buffer overflow detected (%d + %d > %d)\n", enclen, *len, buflen);
         return -1;
      }
      if (enclen > 0) {
         memcpy(&buf[*len], &data[octet_idx], enclen);
         *len += enclen;
      }
      if (enclen >= num_octets)
         break;
   }

   return 0;
}

static struct ast_udptl_protocol* get_proto

(

struct ast_channel *

chan

)

[static, read]

Definition at line 1047 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().

{
   struct ast_udptl_protocol *cur = NULL;

   AST_RWLIST_RDLOCK(&protos);
   AST_RWLIST_TRAVERSE(&protos, cur, list) {
      if (cur->type == chan->tech->type)
         break;
   }
   AST_RWLIST_UNLOCK(&protos);

   return cur;
}

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

Definition at line 1186 of file udptl.c.

References ast_cli_args::argc, ast_cli_args::argv, ast_cli(), ast_gethostbyname(), ast_inet_ntoa(), ast_strdupa, CLI_GENERATE, CLI_INIT, CLI_SHOWUSAGE, CLI_SUCCESS, ast_cli_entry::command, ast_cli_args::fd, hp, udptldebugaddr, and ast_cli_entry::usage.

{
   struct hostent *hp;
   struct ast_hostent ahp;
   int port;
   char *p;
   char *arg;

   switch (cmd) {
   case CLI_INIT:
      e->command = "udptl set debug {on|off|ip}";
      e->usage = 
         "Usage: udptl set debug {on|off|ip host[:port]}\n"
         "       Enable or disable dumping of UDPTL packets.\n"
         "       If ip is specified, limit the dumped packets to those to and from\n"
         "       the specified 'host' with optional port.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }

   if (a->argc < 4 || a->argc > 5)
      return CLI_SHOWUSAGE;

   if (a->argc == 4) {
      if (!strncasecmp(a->argv[3], "on", 2)) {
         udptldebug = 1;
         memset(&udptldebugaddr, 0, sizeof(udptldebugaddr));
         ast_cli(a->fd, "UDPTL Debugging Enabled\n");
      } else if (!strncasecmp(a->argv[3], "off", 3)) {
         udptldebug = 0;
         ast_cli(a->fd, "UDPTL Debugging Disabled\n");
      } else {
         return CLI_SHOWUSAGE;
      }
   } else {
      if (strncasecmp(a->argv[3], "ip", 2))
         return CLI_SHOWUSAGE;
      port = 0;
      arg = ast_strdupa(a->argv[4]);
      p = strstr(arg, ":");
      if (p) {
         *p = '\0';
         p++;
         port = atoi(p);
      }
      hp = ast_gethostbyname(arg, &ahp);
      if (hp == NULL)
         return CLI_SHOWUSAGE;
      udptldebugaddr.sin_family = AF_INET;
      memcpy(&udptldebugaddr.sin_addr, hp->h_addr, sizeof(udptldebugaddr.sin_addr));
      udptldebugaddr.sin_port = htons(port);
      if (port == 0)
         ast_cli(a->fd, "UDPTL Debugging Enabled for IP: %s\n", ast_inet_ntoa(udptldebugaddr.sin_addr));
      else
         ast_cli(a->fd, "UDPTL Debugging Enabled for IP: %s:%d\n", ast_inet_ntoa(udptldebugaddr.sin_addr), port);
      udptldebug = 1;
   }

   return CLI_SUCCESS;
}

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 514 of file udptl.c.

References ast_log(), 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_DEBUG, option_debug, seq, ast_udptl::tx, ast_udptl::tx_seq_no, UDPTL_BUF_MASK, UDPTL_ERROR_CORRECTION_FEC, UDPTL_ERROR_CORRECTION_NONE, UDPTL_ERROR_CORRECTION_REDUNDANCY, and ast_udptl::verbose.

Referenced by ast_udptl_write().

{
   uint8_t fec[LOCAL_FAX_MAX_DATAGRAM * 2];
   int i;
   int j;
   int seq;
   int entry;
   int entries;
   int span;
   int m;
   unsigned int len;
   int limit;
   int high_tide;

   seq = s->tx_seq_no & 0xFFFF;

   /* Map the sequence number to an entry in the circular buffer */
   entry = seq & UDPTL_BUF_MASK;

   /* We save the message in a circular buffer, for generating FEC or
      redundancy sets later on. */
   s->tx[entry].buf_len = ifp_len;
   memcpy(s->tx[entry].buf, ifp, ifp_len);
   
   /* Build the UDPTLPacket */

   len = 0;
   /* Encode the sequence number */
   buf[len++] = (seq >> 8) & 0xFF;
   buf[len++] = seq & 0xFF;

   /* Encode the primary IFP packet */
   if (encode_open_type(buf, buflen, &len, ifp, ifp_len) < 0)
      return -1;

   /* Encode the appropriate type of error recovery information */
   switch (s->error_correction_scheme)
   {
   case UDPTL_ERROR_CORRECTION_NONE:
      /* Encode the error recovery type */
      buf[len++] = 0x00;
      /* The number of entries will always be zero, so it is pointless allowing
         for the fragmented case here. */
      if (encode_length(buf, &len, 0) < 0)
         return -1;
      break;
   case UDPTL_ERROR_CORRECTION_REDUNDANCY:
      /* Encode the error recovery type */
      buf[len++] = 0x00;
      if (s->tx_seq_no > s->error_correction_entries)
         entries = s->error_correction_entries;
      else
         entries = s->tx_seq_no;
      /* The number of entries will always be small, so it is pointless allowing
         for the fragmented case here. */
      if (encode_length(buf, &len, entries) < 0)
         return -1;
      /* Encode the elements */
      for (i = 0; i < entries; i++) {
         j = (entry - i - 1) & UDPTL_BUF_MASK;
         if (encode_open_type(buf, buflen, &len, s->tx[j].buf, s->tx[j].buf_len) < 0) {
            if (option_debug) {
               ast_log(LOG_DEBUG, "Encoding failed at i=%d, j=%d\n", i, j);
            }
            return -1;
         }
      }
      break;
   case UDPTL_ERROR_CORRECTION_FEC:
      span = s->error_correction_span;
      entries = s->error_correction_entries;
      if (seq < s->error_correction_span*s->error_correction_entries) {
         /* In the initial stages, wind up the FEC smoothly */
         entries = seq/s->error_correction_span;
         if (seq < s->error_correction_span)
            span = 0;
      }
      /* Encode the error recovery type */
      buf[len++] = 0x80;
      /* Span is defined as an inconstrained integer, which it dumb. It will only
         ever be a small value. Treat it as such. */
      buf[len++] = 1;
      buf[len++] = span;
      /* The number of entries is defined as a length, but will only ever be a small
         value. Treat it as such. */
      buf[len++] = entries;
      for (m = 0; m < entries; m++) {
         /* Make an XOR'ed entry the maximum length */
         limit = (entry + m) & UDPTL_BUF_MASK;
         high_tide = 0;
         for (i = (limit - span*entries) & UDPTL_BUF_MASK; i != limit; i = (i + entries) & UDPTL_BUF_MASK) {
            if (high_tide < s->tx[i].buf_len) {
               for (j = 0; j < high_tide; j++)
                  fec[j] ^= s->tx[i].buf[j];
               for ( ; j < s->tx[i].buf_len; j++)
                  fec[j] = s->tx[i].buf[j];
               high_tide = s->tx[i].buf_len;
            } else {
               for (j = 0; j < s->tx[i].buf_len; j++)
                  fec[j] ^= s->tx[i].buf[j];
            }
         }
         if (encode_open_type(buf, buflen, &len, fec, high_tide) < 0)
            return -1;
      }
      break;
   }

   if (s->verbose)
      fprintf(stderr, "\n");

   s->tx_seq_no++;
   return len;
}

static int udptl_debug_test_addr

(

const struct sockaddr_in *

addr

)

[inline, static]

Definition at line 177 of file udptl.c.

References udptldebugaddr.

Referenced by ast_udptl_read(), and ast_udptl_write().

{
   if (udptldebug == 0)
      return 0;
   if (udptldebugaddr.sin_addr.s_addr) {
      if (((ntohs(udptldebugaddr.sin_port) != 0) &&
           (udptldebugaddr.sin_port != addr->sin_port)) ||
          (udptldebugaddr.sin_addr.s_addr != addr->sin_addr.s_addr))
         return 0;
   }
   return 1;
}

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

Definition at line 306 of file udptl.c.

References AST_FRAME_MODEM, AST_LIST_NEXT, AST_MODEM_T38, udptl_fec_rx_buffer_t::buf, udptl_fec_rx_buffer_t::buf_len, ast_frame::data, ast_frame::datalen, decode_length(), decode_open_type(), ast_udptl::f, udptl_fec_rx_buffer_t::fec, udptl_fec_rx_buffer_t::fec_entries, udptl_fec_rx_buffer_t::fec_len, udptl_fec_rx_buffer_t::fec_span, ast_frame::frametype, LOCAL_FAX_MAX_DATAGRAM, ast_frame::mallocd, 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().

{
   int stat1;
   int stat2;
   int i;
   int j;
   int k;
   int l;
   int m;
   int x;
   int limit;
   int which;
   unsigned int ptr;
   unsigned int count;
   int total_count;
   int seq_no;
   const uint8_t *ifp;
   const uint8_t *data;
   unsigned int ifp_len;
   int repaired[16];
   const uint8_t *bufs[16];
   unsigned int lengths[16];
   int span;
   int entries;
   int ifp_no;

   ptr = 0;
   ifp_no = 0;
   memset(&s->f[0], 0, sizeof(s->f[0]));

   /* Decode seq_number */
   if (ptr + 2 > len)
      return -1;
   seq_no = (buf[0] << 8) | buf[1];
   ptr += 2;

   /* Break out the primary packet */
   if ((stat1 = decode_open_type(buf, len, &ptr, &ifp, &ifp_len)) != 0)
      return -1;
   /* Decode error_recovery */
   if (ptr + 1 > len)
      return -1;
   if ((buf[ptr++] & 0x80) == 0) {
      /* Secondary packet mode for error recovery */
      if (seq_no > s->rx_seq_no) {
         /* We received a later packet than we expected, so we need to check if we can fill in the gap from the
            secondary packets. */
         total_count = 0;
         do {
            if ((stat2 = decode_length(buf, len, &ptr, &count)) < 0)
               return -1;
            for (i = 0; i < count; i++) {
               if ((stat1 = decode_open_type(buf, len, &ptr, &bufs[total_count + i], &lengths[total_count + i])) != 0)
                  return -1;
            }
            total_count += count;
         }
         while (stat2 > 0);
         /* Step through in reverse order, so we go oldest to newest */
         for (i = total_count; i > 0; i--) {
            if (seq_no - i >= s->rx_seq_no) {
               /* This one wasn't seen before */
               /* Decode the secondary IFP packet */
               //fprintf(stderr, "Secondary %d, len %d\n", seq_no - i, lengths[i - 1]);
               s->f[ifp_no].frametype = AST_FRAME_MODEM;
               s->f[ifp_no].subclass = AST_MODEM_T38;

               s->f[ifp_no].mallocd = 0;
               s->f[ifp_no].seqno = seq_no - i;
               s->f[ifp_no].datalen = lengths[i - 1];
               s->f[ifp_no].data.ptr = (uint8_t *) bufs[i - 1];
               s->f[ifp_no].offset = 0;
               s->f[ifp_no].src = "UDPTL";
               if (ifp_no > 0)
                  AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
               AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
               ifp_no++;
            }
         }
      }
   }
   else
   {
      /* FEC mode for error recovery */
      /* Our buffers cannot tolerate overlength IFP packets in FEC mode */
      if (ifp_len > LOCAL_FAX_MAX_DATAGRAM)
         return -1;
      /* Update any missed slots in the buffer */
      for ( ; seq_no > s->rx_seq_no; s->rx_seq_no++) {
         x = s->rx_seq_no & UDPTL_BUF_MASK;
         s->rx[x].buf_len = -1;
         s->rx[x].fec_len[0] = 0;
         s->rx[x].fec_span = 0;
         s->rx[x].fec_entries = 0;
      }

      x = seq_no & UDPTL_BUF_MASK;

      memset(repaired, 0, sizeof(repaired));

      /* Save the new IFP packet */
      memcpy(s->rx[x].buf, ifp, ifp_len);
      s->rx[x].buf_len = ifp_len;
      repaired[x] = TRUE;

      /* Decode the FEC packets */
      /* The span is defined as an unconstrained integer, but will never be more
         than a small value. */
      if (ptr + 2 > len)
         return -1;
      if (buf[ptr++] != 1)
         return -1;
      span = buf[ptr++];
      s->rx[x].fec_span = span;

      /* The number of entries is defined as a length, but will only ever be a small
         value. Treat it as such. */
      if (ptr + 1 > len)
         return -1;
      entries = buf[ptr++];
      s->rx[x].fec_entries = entries;

      /* Decode the elements */
      for (i = 0; i < entries; i++) {
         if ((stat1 = decode_open_type(buf, len, &ptr, &data, &s->rx[x].fec_len[i])) != 0)
            return -1;
         if (s->rx[x].fec_len[i] > LOCAL_FAX_MAX_DATAGRAM)
            return -1;

         /* Save the new FEC data */
         memcpy(s->rx[x].fec[i], data, s->rx[x].fec_len[i]);
#if 0
         fprintf(stderr, "FEC: ");
         for (j = 0; j < s->rx[x].fec_len[i]; j++)
            fprintf(stderr, "%02X ", data[j]);
         fprintf(stderr, "\n");
#endif
      }

      /* See if we can reconstruct anything which is missing */
      /* TODO: this does not comprehensively hunt back and repair everything that is possible */
      for (l = x; l != ((x - (16 - span*entries)) & UDPTL_BUF_MASK); l = (l - 1) & UDPTL_BUF_MASK) {
         if (s->rx[l].fec_len[0] <= 0)
            continue;
         for (m = 0; m < s->rx[l].fec_entries; m++) {
            limit = (l + m) & UDPTL_BUF_MASK;
            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) {
               if (s->rx[k].buf_len <= 0)
                  which = (which == -1) ? k : -2;
            }
            if (which >= 0) {
               /* Repairable */
               for (j = 0; j < s->rx[l].fec_len[m]; j++) {
                  s->rx[which].buf[j] = s->rx[l].fec[m][j];
                  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)
                     s->rx[which].buf[j] ^= (s->rx[k].buf_len > j) ? s->rx[k].buf[j] : 0;
               }
               s->rx[which].buf_len = s->rx[l].fec_len[m];
               repaired[which] = TRUE;
            }
         }
      }
      /* Now play any new packets forwards in time */
      for (l = (x + 1) & UDPTL_BUF_MASK, j = seq_no - UDPTL_BUF_MASK; l != x; l = (l + 1) & UDPTL_BUF_MASK, j++) {
         if (repaired[l]) {
            //fprintf(stderr, "Fixed packet %d, len %d\n", j, l);
            s->f[ifp_no].frametype = AST_FRAME_MODEM;
            s->f[ifp_no].subclass = AST_MODEM_T38;
         
            s->f[ifp_no].mallocd = 0;
            s->f[ifp_no].seqno = j;
            s->f[ifp_no].datalen = s->rx[l].buf_len;
            s->f[ifp_no].data.ptr = s->rx[l].buf;
            s->f[ifp_no].offset = 0;
            s->f[ifp_no].src = "UDPTL";
            if (ifp_no > 0)
               AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
            AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;
            ifp_no++;
         }
      }
   }

   /* If packets are received out of sequence, we may have already processed this packet from the error
      recovery information in a packet already received. */
   if (seq_no >= s->rx_seq_no) {
      /* Decode the primary IFP packet */
      s->f[ifp_no].frametype = AST_FRAME_MODEM;
      s->f[ifp_no].subclass = AST_MODEM_T38;
      
      s->f[ifp_no].mallocd = 0;
      s->f[ifp_no].seqno = seq_no;
      s->f[ifp_no].datalen = ifp_len;
      s->f[ifp_no].data.ptr = (uint8_t *) ifp;
      s->f[ifp_no].offset = 0;
      s->f[ifp_no].src = "UDPTL";
      if (ifp_no > 0)
         AST_LIST_NEXT(&s->f[ifp_no - 1], frame_list) = &s->f[ifp_no];
      AST_LIST_NEXT(&s->f[ifp_no], frame_list) = NULL;

      ifp_no++;
   }

   s->rx_seq_no = seq_no + 1;
   return ifp_no;
}

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

Definition at line 649 of file udptl.c.

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

Referenced by ast_udptl_new_with_bindaddr().

{
   struct ast_udptl *udptl = cbdata;
   struct ast_frame *f;

   if ((f = ast_udptl_read(udptl))) {
      if (udptl->callback)
         udptl->callback(udptl, f, udptl->data);
   }
   return 1;
}

---

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 1249 of file udptl.c.

int udptldebug [static]

Are we debugging?

Definition at line 79 of file udptl.c.

struct sockaddr_in udptldebugaddr [static]

Debug packets to/from this host

Definition at line 80 of file udptl.c.

Referenced by handle_cli_udptl_set_debug(), and udptl_debug_test_addr().

int udptlend = 4599 [static]

Definition at line 78 of file udptl.c.

int udptlfecentries [static]

Definition at line 84 of file udptl.c.

int udptlfecspan [static]

Definition at line 85 of file udptl.c.

int udptlmaxdatagram [static]

Definition at line 86 of file udptl.c.

int udptlstart = 4500 [static]

Definition at line 77 of file udptl.c.

int use_even_ports [static]

Definition at line 87 of file udptl.c.