udptl.c

		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;
}

static char *handle_cli_udptl_set_debug(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
	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 struct ast_cli_entry cli_udptl[] = {
	AST_CLI_DEFINE(handle_cli_udptl_set_debug, "Enable/Disable UDPTL debugging")
};

static void __ast_udptl_reload(int 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;
	udptlfectype = 0;
	udptlfecentries = 0;
	udptlfecspan = 0;
	udptlmaxdatagram = 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"))) {
			if (strcmp(s, "t38UDPFEC") == 0)
				udptlfectype = 2;
			else if (strcmp(s, "t38UDPRedundancy") == 0)
				udptlfectype = 1;
		}
		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;
			}
		}
		ast_config_destroy(cfg);
	}
	if (udptlstart >= udptlend) {
		ast_log(LOG_WARNING, "Unreasonable values for UDPTL start/end\n");
		udptlstart = 4500;
		udptlend = 4999;
	}
	ast_verb(2, "UDPTL allocating from port range %d -> %d\n", udptlstart, udptlend);
}

int ast_udptl_reload(void)
{
	__ast_udptl_reload(1);
	return 0;
}

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