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osmo-mgw/src/libosmo-mgcp-client/mgcp_client.c

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/* mgcp_utils - common functions to setup an MGCP connection
*/
/* (C) 2016 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <osmocom/core/linuxlist.h>
#include <osmocom/core/select.h>
#include <osmocom/core/write_queue.h>
#include <osmocom/core/msgb.h>
#include <osmocom/core/logging.h>
#include <osmocom/core/byteswap.h>
#include <osmocom/core/socket.h>
#include <osmocom/core/sockaddr_str.h>
#include <osmocom/mgcp_client/mgcp_client.h>
#include <osmocom/mgcp_client/mgcp_client_internal.h>
#include <osmocom/abis/e1_input.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include <limits.h>
#ifndef OSMUX_CID_MAX
#define OSMUX_CID_MAX 255 /* FIXME: use OSMUX_CID_MAX from libosmo-netif? */
#endif
#define LOGPMGW(mgcp, level, fmt, args...) \
LOGP(DLMGCP, level, "MGW(%s) " fmt, mgcp_client_name(mgcp), ## args)
/* Codec descripton for dynamic payload types (SDP) */
const struct value_string osmo_mgcpc_codec_names[] = {
{ CODEC_PCMU_8000_1, "PCMU/8000/1" },
{ CODEC_GSM_8000_1, "GSM/8000/1" },
{ CODEC_PCMA_8000_1, "PCMA/8000/1" },
{ CODEC_G729_8000_1, "G729/8000/1" },
{ CODEC_GSMEFR_8000_1, "GSM-EFR/8000/1" },
{ CODEC_GSMHR_8000_1, "GSM-HR-08/8000/1" },
{ CODEC_AMR_8000_1, "AMR/8000/1" },
{ CODEC_AMRWB_16000_1, "AMR-WB/16000/1" },
{ CODEC_IUFP, "VND.3GPP.IUFP/16000" },
{ CODEC_CLEARMODE, "CLEARMODE/8000" },
{ 0, NULL },
};
/* Get encoding name from a full codec string e,g.
* ("CODEC/8000/2" => returns "CODEC") */
static char *extract_codec_name(const char *str)
{
static char buf[64];
char *pos;
if (!str)
return NULL;
osmo_strlcpy(buf, str, sizeof(buf));
pos = strchr(buf, '/');
if (pos)
*pos = '\0';
return buf;
}
/*! Map a string to a codec.
* \ptmap[in] str input string (e.g "GSM/8000/1", "GSM/8000" or "GSM")
* \returns codec that corresponds to the given string representation. */
enum mgcp_codecs map_str_to_codec(const char *str)
{
unsigned int i;
char *codec_name;
char str_buf[64];
osmo_strlcpy(str_buf, extract_codec_name(str), sizeof(str_buf));
for (i = 0; i < ARRAY_SIZE(osmo_mgcpc_codec_names); i++) {
codec_name = extract_codec_name(osmo_mgcpc_codec_names[i].str);
if (!codec_name)
continue;
if (strcmp(codec_name, str_buf) == 0)
return osmo_mgcpc_codec_names[i].value;
}
return -1;
}
/* Check the ptmap for illegal mappings */
static int check_ptmap(const struct ptmap *ptmap)
{
/* Check if there are mappings that leave the IANA assigned dynamic
* payload type range. Under normal conditions such mappings should
* not occur */
/* Its ok to have a 1:1 mapping in the statically defined
* range, this won't hurt */
if (ptmap->codec == ptmap->pt)
return 0;
if (ptmap->codec < 96 || ptmap->codec > 127)
goto error;
if (ptmap->pt < 96 || ptmap->pt > 127)
goto error;
return 0;
error:
LOGP(DLMGCP, LOGL_ERROR,
"ptmap contains illegal mapping: codec=%u maps to pt=%u\n",
ptmap->codec, ptmap->pt);
return -1;
}
/*! Map a codec to a payload type.
* \ptmap[in] payload pointer to payload type map with specified payload types.
* \ptmap[in] ptmap_len length of the payload type map.
* \ptmap[in] codec the codec for which the payload type should be looked up.
* \returns assigned payload type */
unsigned int map_codec_to_pt(const struct ptmap *ptmap, unsigned int ptmap_len,
enum mgcp_codecs codec)
{
unsigned int i;
/*! Note: If the payload type map is empty or the codec is not found
* in the map, then a 1:1 mapping is performed. If the codec falls
* into the statically defined range or if the mapping table isself
* tries to map to the statically defined range, then the mapping
* is also ignored and a 1:1 mapping is performed instead. */
/* we may return the codec directly since enum mgcp_codecs directly
* corresponds to the statically assigned payload types */
if (codec < 96 || codec > 127)
return codec;
for (i = 0; i < ptmap_len; i++) {
/* Skip illegal map entries */
if (check_ptmap(ptmap) == 0 && ptmap->codec == codec)
return ptmap->pt;
ptmap++;
}
/* If nothing is found, do not perform any mapping */
return codec;
}
/*! Map a payload type to a codec.
* \ptmap[in] payload pointer to payload type map with specified payload types.
* \ptmap[in] ptmap_len length of the payload type map.
* \ptmap[in] payload type for which the codec should be looked up.
* \returns codec that corresponds to the specified payload type */
enum mgcp_codecs map_pt_to_codec(struct ptmap *ptmap, unsigned int ptmap_len,
unsigned int pt)
{
unsigned int i;
/*! Note: If the payload type map is empty or the payload type is not
* found in the map, then a 1:1 mapping is performed. If the payload
* type falls into the statically defined range or if the mapping
* table isself tries to map to the statically defined range, then
* the mapping is also ignored and a 1:1 mapping is performed
* instead. */
/* See also note in map_codec_to_pt() */
if (pt < 96 || pt > 127)
return pt;
for (i = 0; i < ptmap_len; i++) {
if (check_ptmap(ptmap) == 0 && ptmap->pt == pt)
return ptmap->codec;
ptmap++;
}
/* If nothing is found, do not perform any mapping */
return pt;
}
static void _mgcp_client_conf_init(struct mgcp_client_conf *conf)
{
/* NULL and -1 default to MGCP_CLIENT_*_DEFAULT values */
*conf = (struct mgcp_client_conf){
.local_addr = NULL,
.local_port = -1,
.remote_addr = NULL,
.remote_port = -1,
.keepalive = {
.timeout_sec = 0, /* disabled */
.req_interval_sec = 0, /* disabled */
.req_endpoint_name = MGCP_CLIENT_KEEPALIVE_DEFAULT_ENDP,
},
};
INIT_LLIST_HEAD(&conf->reset_epnames);
}
/*! Allocate and initialize MGCP client configuration struct with default values.
* \param[in] ctx talloc context to use as a parent during allocation.
*
* The returned struct can be freed using talloc_free().
*/
struct mgcp_client_conf *mgcp_client_conf_alloc(void *ctx)
{
struct mgcp_client_conf *conf = talloc(ctx, struct mgcp_client_conf);
_mgcp_client_conf_init(conf);
return conf;
}
/*! Initialize MGCP client configuration struct with default values.
* \param[out] conf Client configuration.
*
* This function is deprecated and should not be used, as it may break if size
* of struct mgcp_client_conf changes in the future!
*/
void mgcp_client_conf_init(struct mgcp_client_conf *conf)
{
_mgcp_client_conf_init(conf);
}
static void mgcp_client_handle_response(struct mgcp_client *mgcp,
struct mgcp_response_pending *pending,
struct mgcp_response *response)
{
if (!pending) {
LOGPMGW(mgcp, LOGL_ERROR, "Cannot handle NULL response\n");
return;
}
if (pending->response_cb)
pending->response_cb(response, pending->priv);
else
LOGPMGW(mgcp, LOGL_DEBUG, "MGCP response ignored (NULL cb)\n");
talloc_free(pending);
}
static int mgcp_response_parse_head(struct mgcp_response *r, struct msgb *msg)
{
int comment_pos;
char *end;
if (mgcp_msg_terminate_nul(msg))
goto response_parse_failure;
r->body = (char *)msg->data;
if (sscanf(r->body, "%3d %u %n",
&r->head.response_code, &r->head.trans_id,
&comment_pos) != 2)
goto response_parse_failure;
osmo_strlcpy(r->head.comment, r->body + comment_pos, sizeof(r->head.comment));
end = strchr(r->head.comment, '\r');
if (!end)
goto response_parse_failure;
/* Mark the end of the comment */
*end = '\0';
return 0;
response_parse_failure:
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse MGCP response header\n");
return -EINVAL;
}
/* TODO undup against mgcp_protocol.c:mgcp_check_param() */
static bool mgcp_line_is_valid(const char *line)
{
const size_t line_len = strlen(line);
if (line[0] == '\0')
return true;
if (line_len < 2
|| line[1] != '=') {
LOGP(DLMGCP, LOGL_ERROR,
"Wrong MGCP option format: '%s'\n",
line);
return false;
}
return true;
}
/* Parse a line like "m=audio 16002 RTP/AVP 98", extract port and payload types */
static int mgcp_parse_audio_port_pt(struct mgcp_response *r, char *line)
{
char *pt_str;
char *pt_end;
unsigned long int pt;
unsigned int ptmap_len;
unsigned int i;
/* Extract port information */
if (sscanf(line, "m=audio %hu", &r->audio_port) != 1)
goto response_parse_failure_port;
if (r->audio_port == 0)
goto response_parse_failure_port;
/* Extract payload types */
line = strstr(line, "RTP/AVP ");
if (!line)
goto exit;
/* Clear any previous entries before writing over r->ptmap */
r->ptmap_len = 0;
/* Keep a local ptmap_len to show only the full list after parsing succeeded in whole. */
ptmap_len = 0;
pt_str = strtok(line, " ");
while (1) {
pt_str = strtok(NULL, " ");
if (!pt_str)
break;
errno = 0;
pt = strtoul(pt_str, &pt_end, 0);
if ((errno == ERANGE && pt == ULONG_MAX) || (errno && !pt) ||
pt_str == pt_end) {
LOGP(DLMGCP, LOGL_ERROR, "SDP: cannot parse payload type number from '%s'\n", pt_str);
goto response_parse_failure_pt;
}
/* PT is 7 bit field, higher values not allowed */
if (pt >> 7) {
LOGP(DLMGCP, LOGL_ERROR, "SDP: payload type number out of range: %lu > 127\n", pt);
goto response_parse_failure_pt;
}
/* Do not allow duplicate payload types */
for (i = 0; i < ptmap_len; i++) {
if (r->ptmap[i].pt == pt) {
LOGP(DLMGCP, LOGL_ERROR, "SDP: payload type number %lu listed twice\n", pt);
goto response_parse_failure_pt;
}
}
/* Do not allow excessive payload types */
if (ptmap_len >= ARRAY_SIZE(r->ptmap)) {
LOGP(DLMGCP, LOGL_ERROR,
"SDP: can parse only up to %zu payload type numbers\n", ARRAY_SIZE(r->ptmap));
goto response_parse_failure_pt;
}
/* Some payload type numbers imply a specific codec. For those, using the PT number as enum mgcp_codecs
* yields the correct result. If no more specific information on the codec follows in "a=rtpmap:N"
* lines, then this default number takes over. This only applies for PT below the dynamic range (<96). */
if (pt < 96)
r->ptmap[ptmap_len].codec = pt;
else
r->ptmap[ptmap_len].codec = -1;
r->ptmap[ptmap_len].pt = pt;
ptmap_len++;
}
/* Parsing succeeded, publish all entries. */
r->ptmap_len = ptmap_len;
exit:
return 0;
response_parse_failure_port:
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse SDP parameter port (%s)\n", line);
return -EINVAL;
response_parse_failure_pt:
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse SDP parameter payload types (%s)\n", line);
return -EINVAL;
}
/* Parse an 'a=...' parameter */
static int mgcp_parse_audio_ptime_rtpmap(struct mgcp_response *r, const char *line)
{
unsigned int pt;
unsigned int i;
char codec_resp[64];
int rc;
#define A_PTIME "a=ptime:"
#define A_RTPMAP "a=rtpmap:"
if (osmo_str_startswith(line, A_PTIME)) {
if (sscanf(line, A_PTIME "%u", &r->ptime) != 1) {
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse SDP parameter, invalid ptime (%s)\n", line);
return -EINVAL;
}
} else if (osmo_str_startswith(line, A_RTPMAP)) {
if (sscanf(line, A_RTPMAP "%d %63s", &pt, codec_resp) != 2) {
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse SDP parameter, invalid rtpmap: %s\n", osmo_quote_str(line, -1));
return -EINVAL;
}
rc = map_str_to_codec(codec_resp);
if (rc < 0) {
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse SDP parameter, can't parse codec in rtpmap: %s\n", osmo_quote_str(line, -1));
return -EINVAL;
}
/* Earlier, a line like "m=audio 16002 RTP/AVP 98 112 3" established the desired order of payloads, now
* enrich it with actual codec information provided by "a=rtpmap:..." entries.
* For each, find the entry with the right pt number and add the info there. */
for (i = 0; i < r->ptmap_len; i++) {
if (r->ptmap[i].pt != pt)
continue;
r->ptmap[i].codec = rc;
return 0;
}
/* No entry was found. This is an error in the MGCP protocol, but let's just add another entry
* anyway, to not make it look like it was never there. */
LOGP(DLMGCP, LOGL_ERROR,
"error in MGCP message: 'a=rtpmap:%u' has no matching entry in 'm=audio ... %u'\n",
pt, pt);
if (r->ptmap_len >= ARRAY_SIZE(r->ptmap)) {
LOGP(DLMGCP, LOGL_ERROR,
"cannot parse all codecs: can only store up to %zu rtpmap entries.\n",
ARRAY_SIZE(r->ptmap));
return -ENOSPC;
}
r->ptmap[r->ptmap_len] = (struct ptmap){
.pt = pt,
.codec = rc,
};
r->ptmap_len++;
}
return 0;
}
/* Parse a line like "c=IN IP4 10.11.12.13" */
static int mgcp_parse_audio_ip(struct mgcp_response *r, const char *line)
{
struct in6_addr ip_test;
bool is_ipv6;
if (strncmp("c=IN IP", line, 7) != 0)
goto response_parse_failure;
line += 7;
if (*line == '6')
is_ipv6 = true;
else if (*line == '4')
is_ipv6 = false;
else
goto response_parse_failure;
line++;
if (*line != ' ')
goto response_parse_failure;
line++;
/* Extract and check IP-Address */
if (is_ipv6) {
/* 45 = INET6_ADDRSTRLEN -1 */
if (sscanf(line, "%45s", r->audio_ip) != 1)
goto response_parse_failure;
if (inet_pton(AF_INET6, r->audio_ip, &ip_test) != 1)
goto response_parse_failure;
} else {
/* 15 = INET_ADDRSTRLEN -1 */
if (sscanf(line, "%15s", r->audio_ip) != 1)
goto response_parse_failure;
if (inet_pton(AF_INET, r->audio_ip, &ip_test) != 1)
goto response_parse_failure;
}
return 0;
response_parse_failure:
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse MGCP response header (audio ip)\n");
return -EINVAL;
}
/*! Extract OSMUX CID from an MGCP parameter line (string).
* \param[in] line single parameter line from the MGCP message
* \returns OSMUX CID, -1 wildcard, -2 on error
* FIXME: This is a copy of function in mgcp_msg.c. Have some common.c file between both libs?
*/
static int mgcp_parse_osmux_cid(const char *line)
{
int osmux_cid;
if (strcasecmp(line + 2, "Osmux: *") == 0) {
LOGP(DLMGCP, LOGL_DEBUG, "Parsed wilcard Osmux CID\n");
return -1;
}
if (sscanf(line + 2 + 7, "%u", &osmux_cid) != 1) {
LOGP(DLMGCP, LOGL_ERROR, "Failed parsing Osmux in MGCP msg line: %s\n",
line);
return -2;
}
if (osmux_cid > OSMUX_CID_MAX) { /* OSMUX_CID_MAX from libosmo-netif */
LOGP(DLMGCP, LOGL_ERROR, "Osmux ID too large: %u > %u\n",
osmux_cid, OSMUX_CID_MAX);
return -2;
}
LOGP(DLMGCP, LOGL_DEBUG, "MGW offered Osmux CID %u\n", osmux_cid);
return osmux_cid;
}
/* A new section is marked by a double line break, check a few more
* patterns as there may be variants */
static char *mgcp_find_section_end(char *string)
{
char *rc;
rc = strstr(string, "\n\n");
if (rc)
return rc + 2;
rc = strstr(string, "\n\r\n\r");
if (rc)
return rc + 4;
rc = strstr(string, "\r\n\r\n");
if (rc)
return rc + 4;
return NULL;
}
/*! Parse body (SDP) parameters of the MGCP response
* \param[in,out] r Response data
* \returns 0 on success, -EINVAL on error. */
int mgcp_response_parse_params(struct mgcp_response *r)
{
char *line;
int rc;
char *data;
char *data_ptr;
/* Since this functions performs a destructive parsing, we create a
* local copy of the body data */
OSMO_ASSERT(r->body);
data = talloc_strdup(r, r->body);
OSMO_ASSERT(data);
/* Find beginning of the parameter (SDP) section */
data_ptr = mgcp_find_section_end(data);
if (!data_ptr) {
LOGP(DLMGCP, LOGL_DEBUG, "MGCP response contains no SDP parameters\n");
rc = 0;
goto exit;
}
/* data_ptr now points to the beginning of the section-end-marker; for_each_non_empty_line()
* skips any \r and \n characters for free, so we don't need to skip the marker. */
for_each_non_empty_line(line, data_ptr) {
if (!mgcp_line_is_valid(line))
return -EINVAL;
switch (line[0]) {
case 'a':
rc = mgcp_parse_audio_ptime_rtpmap(r, line);
if (rc)
goto exit;
break;
case 'm':
rc = mgcp_parse_audio_port_pt(r, line);
if (rc)
goto exit;
break;
case 'c':
rc = mgcp_parse_audio_ip(r, line);
if (rc)
goto exit;
break;
default:
/* skip unhandled parameters */
break;
}
}
rc = 0;
exit:
talloc_free(data);
return rc;
}
/* Parse a line like "X: something" */
static int mgcp_parse_head_param(char *result, unsigned int result_len,
char label, const char *line)
{
char label_string[4];
size_t rc;
/* Detect empty parameters */
if (strlen(line) < 4)
goto response_parse_failure;
/* Check if the label matches */
snprintf(label_string, sizeof(label_string), "%c: ", label);
if (memcmp(label_string, line, 3) != 0)
goto response_parse_failure;
/* Copy payload part of the string to destinations (the label string
* is always 3 chars long) */
rc = osmo_strlcpy(result, line + 3, result_len);
if (rc >= result_len) {
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse MGCP response (parameter label: %c):"
" the received conn ID is too long: %zu, maximum is %u characters\n",
label, rc, result_len - 1);
return -ENOSPC;
}
return 0;
response_parse_failure:
LOGP(DLMGCP, LOGL_ERROR,
"Failed to parse MGCP response (parameter label: %c)\n", label);
return -EINVAL;
}
/* Parse MGCP parameters of the response */
static int parse_head_params(struct mgcp_response *r)
{
char *line;
int rc = 0;
OSMO_ASSERT(r->body);
char *data;
char *data_ptr;
char *data_end;
/* Since this functions performs a destructive parsing, we create a
* local copy of the body data */
data = talloc_zero_size(r, strlen(r->body)+1);
OSMO_ASSERT(data);
data_ptr = data;
osmo_strlcpy(data, r->body, strlen(r->body));
/* If there is an SDP body attached, prevent for_each_non_empty_line()
* into running in there, we are not yet interested in the parameters
* stored there. */
data_end = mgcp_find_section_end(data);
if (data_end)
*data_end = '\0';
for_each_non_empty_line(line, data_ptr) {
switch (toupper(line[0])) {
case 'Z':
rc = mgcp_parse_head_param(r->head.endpoint,
sizeof(r->head.endpoint),
'Z', line);
if (rc)
goto exit;
/* A specific endpoint identifier returned by the MGW
* must not contain any wildcard characters */
if (strstr(r->head.endpoint, "*") != NULL) {
rc = -EINVAL;
goto exit;
}
/* A specific endpoint identifier returned by the MGW
* must contain an @ character */
if (strstr(r->head.endpoint, "@") == NULL) {
rc = -EINVAL;
goto exit;
}
break;
case 'I':
rc = mgcp_parse_head_param(r->head.conn_id,
sizeof(r->head.conn_id),
'I', line);
if (rc)
goto exit;
break;
case 'X':
if (strncasecmp("Osmux: ", line + 2, strlen("Osmux: ")) == 0) {
rc = mgcp_parse_osmux_cid(line);
if (rc < 0) {
/* -1: we don't want wildcards in response. -2: error */
rc = -EINVAL;
goto exit;
}
r->head.x_osmo_osmux_use = true;
r->head.x_osmo_osmux_cid = (uint8_t) rc;
rc = 0;
break;
}
/* Ignore unknown X-headers */
break;
default:
/* skip unhandled parameters */
break;
}
}
exit:
talloc_free(data);
return rc;
}
static struct mgcp_response_pending *mgcp_client_response_pending_get(
struct mgcp_client *mgcp,
mgcp_trans_id_t trans_id)
{
struct mgcp_response_pending *pending;
llist_for_each_entry(pending, &mgcp->responses_pending, entry) {
if (pending->trans_id == trans_id) {
llist_del(&pending->entry);
return pending;
}
}
return NULL;
}
/* Feed an MGCP message into the receive processing.
* Parse the head and call any callback registered for the transaction id found
* in the MGCP message. This is normally called directly from the internal
* mgcp_read_cb that reads from the socket connected to the MGCP gateway. This
* function is published mainly to be able to feed data from the test suite.
*/
int mgcp_client_rx(struct mgcp_client *mgcp, struct msgb *msg)
{
struct mgcp_response *r;
struct mgcp_response_pending *pending;
int rc;
r = talloc_zero(mgcp, struct mgcp_response);
OSMO_ASSERT(r);
/* Re-arm keepalive timer if enabled */
if (OSMO_UNLIKELY(mgcp->conn_up == false)) {
LOGPMGW(mgcp, LOGL_NOTICE, "MGCP link to MGW now considered UP\n");
mgcp->conn_up = true;
}
if (mgcp->actual.keepalive.timeout_sec > 0)
osmo_timer_schedule(&mgcp->keepalive_rx_timer, mgcp->actual.keepalive.timeout_sec, 0);
rc = mgcp_response_parse_head(r, msg);
if (rc) {
LOGPMGW(mgcp, LOGL_ERROR, "Cannot parse MGCP response (head)\n");
rc = 1;
goto error;
}
LOGPMGW(mgcp, LOGL_DEBUG, "MGCP client: Rx %d %u %s\n",
r->head.response_code, r->head.trans_id, r->head.comment);
rc = parse_head_params(r);
if (rc) {
LOGPMGW(mgcp, LOGL_ERROR, "Cannot parse MGCP response (head parameters)\n");
rc = 1;
goto error;
}
pending = mgcp_client_response_pending_get(mgcp, r->head.trans_id);
if (!pending) {
LOGPMGW(mgcp, LOGL_ERROR, "Cannot find matching MGCP transaction for trans_id %d\n",
r->head.trans_id);
rc = -ENOENT;
goto error;
}
mgcp_client_handle_response(mgcp, pending, r);
rc = 0;
error:
talloc_free(r);
return rc;
}
static void mgcp_read_cb(struct osmo_io_fd *iofd, int res, struct msgb *msg)
{
struct mgcp_client *mgcp = osmo_iofd_get_data(iofd);
if (res <= 0) {
LOGPMGW(mgcp, LOGL_ERROR, "Failed to read: %s: %d='%s'\n",
osmo_iofd_get_name(iofd), res, strerror(res));
msgb_free(msg);
return;
}
msg->l2h = msg->head;
mgcp_client_rx(mgcp, msg);
talloc_free(msg);
}
static int mgcp_do_write(struct mgcp_client *mgcp, struct msgb *msg)
{
int ret;
LOGPMGW(mgcp, LOGL_DEBUG, "Tx MGCP: %s: len=%u '%s'...\n",
osmo_iofd_get_name(mgcp->iofd), msg->len,
osmo_escape_str((const char *)msg->data, OSMO_MIN(42, msg->len)));
ret = osmo_iofd_write_msgb(mgcp->iofd, msg);
if (ret < 0)
msgb_free(msg);
/* Re-arm the keepalive Tx timer: */
if (mgcp->actual.keepalive.req_interval_sec > 0)
osmo_timer_schedule(&mgcp->keepalive_tx_timer, mgcp->actual.keepalive.req_interval_sec, 0);
return ret;
}
static void mgcp_write_cb(struct osmo_io_fd *iofd, int res, struct msgb *msg)
{
struct mgcp_client *mgcp = osmo_iofd_get_data(iofd);
if (OSMO_UNLIKELY(res != msg->len)) {
LOGPMGW(mgcp, LOGL_ERROR, "Failed to Tx MGCP: %s: %d='%s'; msg: len=%u '%s'...\n",
osmo_iofd_get_name(mgcp->iofd), res, strerror(res),
msg->len, osmo_escape_str((const char *)msg->data, OSMO_MIN(42, msg->len)));
}
}
static const char *_mgcp_client_name_append_domain(const struct mgcp_client *mgcp, const char *name)
{
static char endpoint[MGCP_ENDPOINT_MAXLEN];
int rc;
rc = snprintf(endpoint, sizeof(endpoint), "%s@%s", name, mgcp_client_endpoint_domain(mgcp));
if (rc > sizeof(endpoint) - 1) {
LOGPMGW(mgcp, LOGL_ERROR, "MGCP endpoint exceeds maximum length of %zu: '%s@%s'\n",
sizeof(endpoint) - 1, name, mgcp_client_endpoint_domain(mgcp));
return NULL;
}
if (rc < 1) {
LOGPMGW(mgcp, LOGL_ERROR, "Cannot compose MGCP endpoint name\n");
return NULL;
}
return endpoint;
}
/* Safely ignore the MGCP response to the DLCX sent via _mgcp_client_send_dlcx() */
static void _ignore_mgcp_response(struct mgcp_response *response, void *priv) { }
/* Format DLCX message (fire and forget) and send it off to the MGW */
static void _mgcp_client_send_dlcx(struct mgcp_client *mgcp, const char *epname)
{
struct msgb *msgb_dlcx;
struct mgcp_msg mgcp_msg_dlcx = {
.verb = MGCP_VERB_DLCX,
.presence = MGCP_MSG_PRESENCE_ENDPOINT,
};
osmo_strlcpy(mgcp_msg_dlcx.endpoint, epname, sizeof(mgcp_msg_dlcx.endpoint));
msgb_dlcx = mgcp_msg_gen(mgcp, &mgcp_msg_dlcx);
mgcp_client_tx(mgcp, msgb_dlcx, &_ignore_mgcp_response, NULL);
}
/* Format AuditEndpoint message (fire and forget) and send it off to the MGW */
static void _mgcp_client_send_auep(struct mgcp_client *mgcp, const char *epname)
{
struct msgb *msgb_auep;
struct mgcp_msg mgcp_msg_auep = {
.verb = MGCP_VERB_AUEP,
.presence = MGCP_MSG_PRESENCE_ENDPOINT,
};
OSMO_STRLCPY_ARRAY(mgcp_msg_auep.endpoint, epname);
msgb_auep = mgcp_msg_gen(mgcp, &mgcp_msg_auep);
mgcp_client_tx(mgcp, msgb_auep, &_ignore_mgcp_response, NULL);
}
static void mgcp_client_keepalive_tx_timer_cb(void *data)
{
struct mgcp_client *mgcp = (struct mgcp_client *)data;
LOGPMGW(mgcp, LOGL_INFO, "Triggering keepalive MGCP request\n");
const char *epname = _mgcp_client_name_append_domain(mgcp, mgcp->actual.keepalive.req_endpoint_name);
_mgcp_client_send_auep(mgcp, epname);
/* Re-arm the timer: */
osmo_timer_schedule(&mgcp->keepalive_tx_timer, mgcp->actual.keepalive.req_interval_sec, 0);
}
static void mgcp_client_keepalive_rx_timer_cb(void *data)
{
struct mgcp_client *mgcp = (struct mgcp_client *)data;
LOGPMGW(mgcp, LOGL_ERROR, "MGCP link to MGW now considered DOWN (keepalive timeout, more than %u seconds with no answer from MGW)\n",
mgcp->actual.keepalive.timeout_sec);
mgcp->conn_up = false;
/* TODO: Potentially time out all ongoing transactions for that MGW. Maybe based on VTY cfg? */
}
struct mgcp_client *mgcp_client_init(void *ctx,
struct mgcp_client_conf *conf)
{
struct mgcp_client *mgcp;
struct reset_ep *reset_ep;
struct reset_ep *actual_reset_ep;
mgcp = talloc_zero(ctx, struct mgcp_client);
if (!mgcp)
return NULL;
INIT_LLIST_HEAD(&mgcp->responses_pending);
mgcp->next_trans_id = 1;
mgcp->actual.local_addr = conf->local_addr ? conf->local_addr :
MGCP_CLIENT_LOCAL_ADDR_DEFAULT;
mgcp->actual.local_port = conf->local_port > 0 ? (uint16_t)conf->local_port :
MGCP_CLIENT_LOCAL_PORT_DEFAULT;
mgcp->actual.remote_addr = conf->remote_addr ? conf->remote_addr :
MGCP_CLIENT_REMOTE_ADDR_DEFAULT;
mgcp->actual.remote_port = conf->remote_port >= 0 ? (uint16_t)conf->remote_port :
MGCP_CLIENT_REMOTE_PORT_DEFAULT;
if (osmo_strlcpy(mgcp->actual.endpoint_domain_name, conf->endpoint_domain_name,
sizeof(mgcp->actual.endpoint_domain_name))
>= sizeof(mgcp->actual.endpoint_domain_name)) {
LOGPMGW(mgcp, LOGL_ERROR, "MGCP client: endpoint domain name is too long, max length is %zu: '%s'\n",
sizeof(mgcp->actual.endpoint_domain_name) - 1, conf->endpoint_domain_name);
talloc_free(mgcp);
return NULL;
}
LOGPMGW(mgcp, LOGL_NOTICE, "MGCP client: using endpoint domain '@%s'\n", mgcp_client_endpoint_domain(mgcp));
INIT_LLIST_HEAD(&mgcp->actual.reset_epnames);
llist_for_each_entry(reset_ep, &conf->reset_epnames, list) {
actual_reset_ep = talloc_memdup(mgcp, reset_ep, sizeof(*reset_ep));
llist_add_tail(&actual_reset_ep->list, &mgcp->actual.reset_epnames);
}
if (conf->description)
mgcp->actual.description = talloc_strdup(mgcp, conf->description);
memcpy(&mgcp->actual.keepalive, &conf->keepalive, sizeof(conf->keepalive));
osmo_timer_setup(&mgcp->keepalive_tx_timer, mgcp_client_keepalive_tx_timer_cb, mgcp);
osmo_timer_setup(&mgcp->keepalive_rx_timer, mgcp_client_keepalive_rx_timer_cb, mgcp);
return mgcp;
}
static const struct osmo_io_ops mgcp_clnt_ioops = {
.read_cb = mgcp_read_cb,
.write_cb = mgcp_write_cb,
};
/*! Initialize client connection (opens socket)
* \param[in,out] mgcp MGCP client descriptor.
* \returns 0 on success, -EINVAL on error. */
int mgcp_client_connect(struct mgcp_client *mgcp)
{
int rc;
struct reset_ep *reset_ep;
const char *epname;
bool some_dlcx_sent = false;
if (!mgcp) {
LOGPMGW(mgcp, LOGL_FATAL, "Client not initialized properly\n");
return -EINVAL;
}
rc = osmo_sock_init2(AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, mgcp->actual.local_addr,
mgcp->actual.local_port, mgcp->actual.remote_addr, mgcp->actual.remote_port,
OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT);
if (rc < 0) {
LOGPMGW(mgcp, LOGL_FATAL,
"Failed to initialize socket %s:%u -> %s:%u for MGW: %s\n",
mgcp->actual.local_addr ? mgcp->actual.local_addr : "(any)", mgcp->actual.local_port,
mgcp->actual.remote_addr ? mgcp->actual.local_addr : "(any)", mgcp->actual.remote_port,
strerror(errno));
goto error_free;
}
mgcp->iofd = osmo_iofd_setup(mgcp, rc, osmo_sock_get_name2(rc), OSMO_IO_FD_MODE_READ_WRITE,
&mgcp_clnt_ioops, mgcp);
if (!mgcp->iofd)
goto error_close_fd;
LOGPMGW(mgcp, LOGL_INFO, "MGW connection: %s\n", osmo_iofd_get_name(mgcp->iofd));
osmo_iofd_register(mgcp->iofd, -1);
osmo_iofd_set_alloc_info(mgcp->iofd, 4096, 128);
osmo_iofd_set_txqueue_max_length(mgcp->iofd, 1024);
/* If configured, send a DLCX message to the endpoints that are configured to
* be reset on startup. Usually this is a wildcarded endpoint. */
llist_for_each_entry(reset_ep, &mgcp->actual.reset_epnames, list) {
epname = _mgcp_client_name_append_domain(mgcp, reset_ep->name);
LOGPMGW(mgcp, LOGL_INFO, "Sending DLCX to: %s\n", epname);
_mgcp_client_send_dlcx(mgcp, epname);
some_dlcx_sent = true;
}
if (mgcp->actual.keepalive.req_interval_sec > 0) {
if (!some_dlcx_sent) {
/* Attempt an immediate probe to find out if link is UP or DOWN: */
osmo_timer_schedule(&mgcp->keepalive_tx_timer, 0, 0);
}
/* else: keepalive_tx_timer was already scheduled (if needed) down in the stack during Tx DLCX above */
} else {
/* Assume link is UP by default, so that this MGW can be selected: */
mgcp->conn_up = true;
}
if (mgcp->actual.keepalive.timeout_sec > 0)
osmo_timer_schedule(&mgcp->keepalive_rx_timer, mgcp->actual.keepalive.timeout_sec, 0);
return 0;
error_close_fd:
close(rc);
error_free:
return rc;
}
/*! DEPRECATED: Initialize client connection (opens socket)
* \param[in,out] mgcp MGCP client descriptor.
* \returns 0 on success, -EINVAL on error. */
int mgcp_client_connect2(struct mgcp_client *mgcp, unsigned int retry_n_ports)
{
return mgcp_client_connect(mgcp);
}
/*! Terminate client connection
* \param[in,out] mgcp MGCP client descriptor.
* \returns 0 on success, -EINVAL on error. */
void mgcp_client_disconnect(struct mgcp_client *mgcp)
{
if (!mgcp) {
LOGP(DLMGCP, LOGL_FATAL, "MGCP client not initialized properly\n");
return;
}
/* Disarm keepalive Tx/Rx timer until next connect() */
osmo_timer_del(&mgcp->keepalive_rx_timer);
osmo_timer_del(&mgcp->keepalive_tx_timer);
mgcp->conn_up = false;
osmo_iofd_txqueue_clear(mgcp->iofd);
LOGPMGW(mgcp, LOGL_INFO, "MGCP association: %s -- closed!\n", osmo_iofd_get_name(mgcp->iofd));
osmo_iofd_free(mgcp->iofd);
}
/*! Get the IP-Aaddress of the associated MGW as string.
* \param[in] mgcp MGCP client descriptor.
* \returns a pointer to the address string. */
const char *mgcp_client_remote_addr_str(struct mgcp_client *mgcp)
{
return mgcp->actual.remote_addr;
}
/*! Get the IP-Port of the associated MGW.
* \param[in] mgcp MGCP client descriptor.
* \returns port number. */
uint16_t mgcp_client_remote_port(struct mgcp_client *mgcp)
{
return mgcp->actual.remote_port;
}
/*! Get the IP-Address of the associated MGW as its numeric representation.
* DEPRECATED, DON'T USE.
* \param[in] mgcp MGCP client descriptor.
* \returns IP-Address as 32 bit integer (network byte order) */
uint32_t mgcp_client_remote_addr_n(struct mgcp_client *mgcp)
{
return 0;
}
/* To compose endpoint names, usually for CRCX, use this as domain name.
* For example, snprintf("rtpbridge\*@%s", mgcp_client_endpoint_domain(mgcp)). */
const char *mgcp_client_endpoint_domain(const struct mgcp_client *mgcp)
{
return mgcp->actual.endpoint_domain_name[0] ? mgcp->actual.endpoint_domain_name : "mgw";
}
/*! Compose endpoint name for a wildcarded request to the virtual trunk
* \param[in] mgcp MGCP client descriptor.
* \returns string containing the endpoint name (e.g. rtpbridge\*@mgw) */
const char *mgcp_client_rtpbridge_wildcard(const struct mgcp_client *mgcp)
{
return _mgcp_client_name_append_domain(mgcp, "rtpbridge/*");
}
/*! Compose endpoint name for an E1 endpoint.
* \param[in] ctx talloc context.
* \param[in] mgcp MGCP client descriptor.
* \param[in] trunk_id id number of the E1 trunk (1-64).
* \param[in] ts timeslot on the E1 trunk (1-31).
* \param[in] rate bitrate used on the E1 trunk (e.g 16 for 16kbit).
* \param[in] offset bit offset of the E1 subslot (e.g. 4 for the third 16k subslot).
* \returns string containing the endpoint name (e.g. ds/e1-1/s-1/su16-4). */
const char *mgcp_client_e1_epname(void *ctx, const struct mgcp_client *mgcp, uint8_t trunk_id, uint8_t ts,
uint8_t rate, uint8_t offset)
{
/* See also comment in libosmo-mgcp, mgcp_client.c, gen_e1_epname() */
const uint8_t valid_rates[] = { 64, 32, 32, 16, 16, 16, 16, 8, 8, 8, 8, 8, 8, 8, 8 };
const uint8_t valid_offsets[] = { 0, 0, 4, 0, 2, 4, 6, 0, 1, 2, 3, 4, 5, 6, 7 };
uint8_t i;
bool rate_offs_valid = false;
char *epname;
epname =
talloc_asprintf(ctx, "ds/e1-%u/s-%u/su%u-%u@%s", trunk_id, ts, rate, offset,
mgcp_client_endpoint_domain(mgcp));
if (!epname) {
LOGPMGW(mgcp, LOGL_ERROR, "Cannot compose MGCP e1-endpoint name!\n");
return NULL;
}
/* Check if the supplied rate/offset pair resembles a valid combination */
for (i = 0; i < sizeof(valid_rates); i++) {
if (valid_rates[i] == rate && valid_offsets[i] == offset)
rate_offs_valid = true;
}
if (!rate_offs_valid) {
LOGPMGW(mgcp, LOGL_ERROR,
"Cannot compose MGCP e1-endpoint name (%s), rate(%u)/offset(%u) combination is invalid!\n",
epname, rate, offset);
talloc_free(epname);
return NULL;
}
/* An E1 line has a maximum of 32 timeslots, while the first (ts=0) is
* reserverd for framing and alignment, so we can not use it here. */
if (ts == 0 || ts > NUM_E1_TS-1) {
LOGPMGW(mgcp, LOGL_ERROR,
"Cannot compose MGCP e1-endpoint name (%s), E1-timeslot number (%u) is invalid!\n",
epname, ts);
talloc_free(epname);
return NULL;
}
return epname;
}
struct mgcp_response_pending *mgcp_client_pending_add(struct mgcp_client *mgcp, mgcp_trans_id_t trans_id,
mgcp_response_cb_t response_cb, void *priv)
{
struct mgcp_response_pending *pending;
pending = talloc_zero(mgcp, struct mgcp_response_pending);
if (!pending)
return NULL;
pending->trans_id = trans_id;
pending->response_cb = response_cb;
pending->priv = priv;
llist_add_tail(&pending->entry, &mgcp->responses_pending);
return pending;
}
/* Send the MGCP message in msg to the MGW and handle a response with
* response_cb. NOTE: the response_cb still needs to call
* mgcp_response_parse_params(response) to get the parsed parameters -- to
* potentially save some CPU cycles, only the head line has been parsed when
* the response_cb is invoked.
* Before the priv pointer becomes invalid, e.g. due to transaction timeout,
* mgcp_client_cancel() needs to be called for this transaction.
*/
int mgcp_client_tx(struct mgcp_client *mgcp, struct msgb *msg,
mgcp_response_cb_t response_cb, void *priv)
{
struct mgcp_response_pending *pending = NULL;
mgcp_trans_id_t trans_id;
int rc;
trans_id = msg->cb[MSGB_CB_MGCP_TRANS_ID];
if (!trans_id) {
LOGPMGW(mgcp, LOGL_ERROR,
"Unset transaction id in mgcp send request\n");
talloc_free(msg);
return -EINVAL;
}
/* Do not allocate a dummy 'mgcp_response_pending' entry */
if (response_cb != NULL) {
pending = mgcp_client_pending_add(mgcp, trans_id, response_cb, priv);
if (!pending) {
talloc_free(msg);
return -ENOMEM;
}
}
if (msgb_l2len(msg) > 4096) {
LOGPMGW(mgcp, LOGL_ERROR,
"Cannot send, MGCP message too large: %u\n",
msgb_l2len(msg));
msgb_free(msg);
rc = -EINVAL;
goto mgcp_tx_error;
}
rc = mgcp_do_write(mgcp, msg);
if (rc) {
LOGPMGW(mgcp, LOGL_FATAL, "Could not queue message to MGW\n");
goto mgcp_tx_error;
} else
LOGPMGW(mgcp, LOGL_DEBUG, "Queued %u bytes for MGW\n",
msgb_l2len(msg));
return 0;
mgcp_tx_error:
if (!pending)
return rc;
/* Dequeue pending response, it's going to be free()d */
llist_del(&pending->entry);
/* Pass NULL to response cb to indicate an error */
mgcp_client_handle_response(mgcp, pending, NULL);
return rc;
}
/*! Cancel a pending transaction.
* \param[in] mgcp MGCP client descriptor.
* \param[in,out] trans_id Transaction id.
* \returns 0 on success, -ENOENT on error.
*
* Should a priv pointer passed to mgcp_client_tx() become invalid, this function must be called. In
* practical terms, if the caller of mgcp_client_tx() wishes to tear down a transaction without having
* received a response this function must be called. The trans_id can be obtained by calling
* mgcp_msg_trans_id() on the msgb produced by mgcp_msg_gen(). */
int mgcp_client_cancel(struct mgcp_client *mgcp, mgcp_trans_id_t trans_id)
{
struct mgcp_response_pending *pending = mgcp_client_response_pending_get(mgcp, trans_id);
if (!pending) {
/*! Note: it is not harmful to cancel a transaction twice. */
LOGPMGW(mgcp, LOGL_ERROR, "Cannot cancel, no such transaction: %u\n", trans_id);
return -ENOENT;
}
LOGPMGW(mgcp, LOGL_DEBUG, "Canceled transaction %u\n", trans_id);
talloc_free(pending);
return 0;
/*! We don't really need to clean up the wqueue: In all sane cases, the msgb has already been sent
* out and is no longer in the wqueue. If it still is in the wqueue, then sending MGCP messages
* per se is broken and the program should notice so by a full wqueue. Even if this was called
* before we had a chance to send out the message and it is still going to be sent, we will just
* ignore the reply to it later. Removing a msgb from the wqueue here would just introduce more
* bug surface in terms of failing to update wqueue API's counters or some such.
*/
}
static mgcp_trans_id_t mgcp_client_next_trans_id(struct mgcp_client *mgcp)
{
/* avoid zero trans_id to distinguish from unset trans_id */
if (!mgcp->next_trans_id)
mgcp->next_trans_id ++;
return mgcp->next_trans_id ++;
}
#define MGCP_CRCX_MANDATORY (MGCP_MSG_PRESENCE_ENDPOINT | \
MGCP_MSG_PRESENCE_CALL_ID | \
MGCP_MSG_PRESENCE_CONN_MODE)
#define MGCP_MDCX_MANDATORY (MGCP_MSG_PRESENCE_ENDPOINT | \
MGCP_MSG_PRESENCE_CALL_ID | \
MGCP_MSG_PRESENCE_CONN_ID)
#define MGCP_DLCX_MANDATORY (MGCP_MSG_PRESENCE_ENDPOINT)
#define MGCP_AUEP_MANDATORY (MGCP_MSG_PRESENCE_ENDPOINT)
#define MGCP_RSIP_MANDATORY 0 /* none */
/* Helper function for mgcp_msg_gen(): Add LCO information to MGCP message */
static int add_lco(struct msgb *msg, struct mgcp_msg *mgcp_msg)
{
unsigned int i;
const char *codec;
#define MSGB_PRINTF_OR_RET(FMT, ARGS...) do { \
if (msgb_printf(msg, FMT, ##ARGS) != 0) { \
LOGP(DLMGCP, LOGL_ERROR, "Message buffer too small, can not generate MGCP/SDP message\n"); \
return -ENOBUFS; \
} \
} while (0)
MSGB_PRINTF_OR_RET("L:");
if (mgcp_msg->ptime)
MSGB_PRINTF_OR_RET(" p:%u,", mgcp_msg->ptime);
if (mgcp_msg->ptmap_len) {
MSGB_PRINTF_OR_RET(" a:");
for (i = 0; i < mgcp_msg->ptmap_len; i++) {
codec = get_value_string_or_null(osmo_mgcpc_codec_names, mgcp_msg->ptmap[i].codec);
/* Note: Use codec descriptors from enum mgcp_codecs
* in mgcp_client only! */
if (!codec)
return -EINVAL;
MSGB_PRINTF_OR_RET("%s", extract_codec_name(codec));
if (i < mgcp_msg->ptmap_len - 1)
MSGB_PRINTF_OR_RET(";");
}
MSGB_PRINTF_OR_RET(",");
}
MSGB_PRINTF_OR_RET(" nt:IN\r\n");
return 0;
#undef MSGB_PRINTF_OR_RET
}
/* Helper function for mgcp_msg_gen(): Add SDP information to MGCP message */
static int add_sdp(struct msgb *msg, struct mgcp_msg *mgcp_msg, struct mgcp_client *mgcp)
{
unsigned int i;
char local_ip[INET6_ADDRSTRLEN];
int local_ip_family, audio_ip_family;
const char *codec;
unsigned int pt;
#define MSGB_PRINTF_OR_RET(FMT, ARGS...) do { \
if (msgb_printf(msg, FMT, ##ARGS) != 0) { \
LOGPMGW(mgcp, LOGL_ERROR, "Message buffer too small, can not generate MGCP message (SDP)\n"); \
return -ENOBUFS; \
} \
} while (0)
/* Add separator to mark the beginning of the SDP block */
MSGB_PRINTF_OR_RET("\r\n");
/* Add SDP protocol version */
MSGB_PRINTF_OR_RET("v=0\r\n");
/* Determine local IP-Address */
if (osmo_sock_local_ip(local_ip, mgcp->actual.remote_addr) < 0) {
LOGPMGW(mgcp, LOGL_ERROR,
"Could not determine local IP-Address!\n");
return -EINVAL;
}
local_ip_family = osmo_ip_str_type(local_ip);
if (local_ip_family == AF_UNSPEC)
return -EINVAL;
/* Add owner/creator (SDP) */
MSGB_PRINTF_OR_RET("o=- %x 23 IN IP%c %s\r\n", mgcp_msg->call_id,
local_ip_family == AF_INET6 ? '6' : '4',
local_ip);
/* Add session name (none) */
MSGB_PRINTF_OR_RET("s=-\r\n");
/* Add RTP address */
if (mgcp_msg->presence & MGCP_MSG_PRESENCE_AUDIO_IP) {
audio_ip_family = osmo_ip_str_type(mgcp_msg->audio_ip);
if (audio_ip_family == AF_UNSPEC)
return -EINVAL;
if (strlen(mgcp_msg->audio_ip) <= 0) {
LOGPMGW(mgcp, LOGL_ERROR,
"Empty ip address, can not generate MGCP message\n");
return -EINVAL;
}
MSGB_PRINTF_OR_RET("c=IN IP%c %s\r\n",
audio_ip_family == AF_INET6 ? '6' : '4',
mgcp_msg->audio_ip);
}
/* Add time description, active time (SDP) */
MSGB_PRINTF_OR_RET("t=0 0\r\n");
/* Add RTP address port and codecs */
if (mgcp_msg->presence & MGCP_MSG_PRESENCE_AUDIO_PORT) {
if (mgcp_msg->audio_port == 0) {
LOGPMGW(mgcp, LOGL_ERROR,
"Invalid port number, can not generate MGCP message\n");
return -EINVAL;
}
MSGB_PRINTF_OR_RET("m=audio %u RTP/AVP", mgcp_msg->audio_port);
for (i = 0; i < mgcp_msg->ptmap_len; i++)
MSGB_PRINTF_OR_RET(" %u", mgcp_msg->ptmap[i].pt);
MSGB_PRINTF_OR_RET("\r\n");
}
/* Add optional codec parameters (fmtp) */
if (mgcp_msg->param_present) {
for (i = 0; i < mgcp_msg->ptmap_len; i++) {
/* The following is only applicable for AMR */
if (mgcp_msg->ptmap[i].codec != CODEC_AMR_8000_1
&& mgcp_msg->ptmap[i].codec != CODEC_AMRWB_16000_1)
continue;
pt = mgcp_msg->ptmap[i].pt;
if (mgcp_msg->param.amr_octet_aligned_present && mgcp_msg->param.amr_octet_aligned)
MSGB_PRINTF_OR_RET("a=fmtp:%u octet-align=1\r\n", pt);
else if (mgcp_msg->param.amr_octet_aligned_present && !mgcp_msg->param.amr_octet_aligned)
MSGB_PRINTF_OR_RET("a=fmtp:%u octet-align=0\r\n", pt);
}
}
for (i = 0; i < mgcp_msg->ptmap_len; i++) {
pt = mgcp_msg->ptmap[i].pt;
/* Note: Only dynamic payload type from the range 96-127
* require to be explained further via rtpmap. All others
* are implcitly definedby the number in m=audio */
if (pt >= 96 && pt <= 127) {
codec = get_value_string_or_null(osmo_mgcpc_codec_names, mgcp_msg->ptmap[i].codec);
/* Note: Use codec descriptors from enum mgcp_codecs
* in mgcp_client only! */
if (!codec)
return -EINVAL;
MSGB_PRINTF_OR_RET("a=rtpmap:%u %s\r\n", pt, codec);
}
}
if (mgcp_msg->ptime)
MSGB_PRINTF_OR_RET("a=ptime:%u\r\n", mgcp_msg->ptime);
return 0;
#undef MSGB_PRINTF_OR_RET
}
/*! Generate an MGCP message
* \param[in] mgcp MGCP client descriptor.
* \param[in] mgcp_msg Message description
* \returns message buffer on success, NULL on error. */
struct msgb *mgcp_msg_gen(struct mgcp_client *mgcp, struct mgcp_msg *mgcp_msg)
{
mgcp_trans_id_t trans_id = mgcp_client_next_trans_id(mgcp);
uint32_t mandatory_mask;
struct msgb *msg = msgb_alloc_headroom(4096, 128, "MGCP tx");
bool use_sdp = false;
char buf[32];
#define MSGB_PRINTF_OR_RET(FMT, ARGS...) do { \
if (msgb_printf(msg, FMT, ##ARGS) != 0) { \
LOGPMGW(mgcp, LOGL_ERROR, "Message buffer too small, can not generate MGCP/SDP message\n"); \
goto exit_error; \
} \
} while (0)
msg->l2h = msg->data;
msg->cb[MSGB_CB_MGCP_TRANS_ID] = trans_id;
/* Add command verb */
switch (mgcp_msg->verb) {
case MGCP_VERB_CRCX:
mandatory_mask = MGCP_CRCX_MANDATORY;
MSGB_PRINTF_OR_RET("CRCX %u", trans_id);
break;
case MGCP_VERB_MDCX:
mandatory_mask = MGCP_MDCX_MANDATORY;
MSGB_PRINTF_OR_RET("MDCX %u", trans_id);
break;
case MGCP_VERB_DLCX:
mandatory_mask = MGCP_DLCX_MANDATORY;
MSGB_PRINTF_OR_RET("DLCX %u", trans_id);
break;
case MGCP_VERB_AUEP:
mandatory_mask = MGCP_AUEP_MANDATORY;
MSGB_PRINTF_OR_RET("AUEP %u", trans_id);
break;
case MGCP_VERB_RSIP:
mandatory_mask = MGCP_RSIP_MANDATORY;
MSGB_PRINTF_OR_RET("RSIP %u", trans_id);
break;
default:
LOGPMGW(mgcp, LOGL_ERROR, "Invalid command verb, can not generate MGCP message\n");
goto exit_error;
}
/* Check if mandatory fields are missing */
if (!((mgcp_msg->presence & mandatory_mask) == mandatory_mask)) {
LOGPMGW(mgcp, LOGL_ERROR,
"One or more missing mandatory fields, can not generate MGCP message\n");
goto exit_error;
}
/* Add endpoint name */
if (mgcp_msg->presence & MGCP_MSG_PRESENCE_ENDPOINT) {
if (strlen(mgcp_msg->endpoint) <= 0) {
LOGPMGW(mgcp, LOGL_ERROR, "Empty endpoint name, can not generate MGCP message\n");
goto exit_error;
}
if (strstr(mgcp_msg->endpoint, "@") == NULL) {
LOGPMGW(mgcp, LOGL_ERROR,
"Endpoint name (%s) lacks separator (@), can not generate MGCP message\n",
mgcp_msg->endpoint);
goto exit_error;
}
MSGB_PRINTF_OR_RET(" %s", mgcp_msg->endpoint);
}
/* Add protocol version */
MSGB_PRINTF_OR_RET(" MGCP 1.0\r\n");
/* Add call id */
if (mgcp_msg->presence & MGCP_MSG_PRESENCE_CALL_ID)
MSGB_PRINTF_OR_RET("C: %x\r\n", mgcp_msg->call_id);
/* Add connection id */
if (mgcp_msg->presence & MGCP_MSG_PRESENCE_CONN_ID) {
if (strlen(mgcp_msg->conn_id) <= 0) {
LOGPMGW(mgcp, LOGL_ERROR, "Empty connection id, can not generate MGCP message\n");
goto exit_error;
}
MSGB_PRINTF_OR_RET("I: %s\r\n", mgcp_msg->conn_id);
}
/* Using SDP makes sense when a valid IP or Port is specified,
* if we do not know this information yet, we fall back to LCO */
if (mgcp_msg->presence & MGCP_MSG_PRESENCE_AUDIO_IP
|| mgcp_msg->presence & MGCP_MSG_PRESENCE_AUDIO_PORT)
use_sdp = true;
/* Add local connection options (LCO) */
if (!use_sdp
&& (mgcp_msg->verb == MGCP_VERB_CRCX
|| mgcp_msg->verb == MGCP_VERB_MDCX)) {
if (add_lco(msg, mgcp_msg) < 0) {
LOGPMGW(mgcp, LOGL_ERROR, "Failed to add LCO, can not generate MGCP message\n");
goto exit_error;
}
}
/* Add mode */
if (mgcp_msg->presence & MGCP_MSG_PRESENCE_CONN_MODE)
MSGB_PRINTF_OR_RET("M: %s\r\n", mgcp_client_cmode_name(mgcp_msg->conn_mode));
/* Add X-Osmo-IGN */
if ((mgcp_msg->presence & MGCP_MSG_PRESENCE_X_OSMO_IGN)
&& (mgcp_msg->x_osmo_ign != 0))
MSGB_PRINTF_OR_RET(MGCP_X_OSMO_IGN_HEADER "%s\r\n",
mgcp_msg->x_osmo_ign & MGCP_X_OSMO_IGN_CALLID ? " C" : "");
/* Add X-Osmo-Osmux */
if ((mgcp_msg->presence & MGCP_MSG_PRESENCE_X_OSMO_OSMUX_CID)) {
if (mgcp_msg->x_osmo_osmux_cid < -1 || mgcp_msg->x_osmo_osmux_cid > OSMUX_CID_MAX) {
LOGPMGW(mgcp, LOGL_ERROR, "Wrong Osmux CID %d, can not generate MGCP message\n",
mgcp_msg->x_osmo_osmux_cid);
goto exit_error;
}
snprintf(buf, sizeof(buf), " %d", mgcp_msg->x_osmo_osmux_cid);
MSGB_PRINTF_OR_RET(MGCP_X_OSMO_OSMUX_HEADER "%s\r\n",
mgcp_msg->x_osmo_osmux_cid == -1 ? " *" : buf);
}
/* Add session description protocol (SDP) */
if (use_sdp
&& (mgcp_msg->verb == MGCP_VERB_CRCX
|| mgcp_msg->verb == MGCP_VERB_MDCX)) {
if (add_sdp(msg, mgcp_msg, mgcp) < 0) {
LOGPMGW(mgcp, LOGL_ERROR, "Failed to add SDP, can not generate MGCP message\n");
goto exit_error;
}
}
return msg;
exit_error:
msgb_free(msg);
return NULL;
#undef MSGB_PRINTF_OR_RET
}
/*! Retrieve the MGCP transaction ID from a msgb generated by mgcp_msg_gen()
* \param[in] msg message buffer
* \returns Transaction id. */
mgcp_trans_id_t mgcp_msg_trans_id(struct msgb *msg)
{
return (mgcp_trans_id_t)msg->cb[MSGB_CB_MGCP_TRANS_ID];
}
/*! Get the configuration parameters for a given MGCP client instance
* \param[in] mgcp MGCP client descriptor.
* \returns configuration */
struct mgcp_client_conf *mgcp_client_conf_actual(struct mgcp_client *mgcp)
{
return &mgcp->actual;
}
const struct value_string mgcp_client_connection_mode_strs[] = {
{ MGCP_CONN_NONE, "none" },
{ MGCP_CONN_RECV_SEND, "sendrecv" },
{ MGCP_CONN_SEND_ONLY, "sendonly" },
{ MGCP_CONN_RECV_ONLY, "recvonly" },
{ MGCP_CONN_CONFECHO, "confecho" },
{ MGCP_CONN_LOOPBACK, "loopback" },
{ 0, NULL }
};
/*! Get MGCP client instance name (VTY).
* \param[in] mgcp MGCP client descriptor.
* \returns MGCP client name.
*
* The user can only modify the name of an MGCP client instance when it is
* part of a pool. For single MGCP client instances and MGCP client instance
* where no description is set via the VTY, the MGW domain name will be used
* as name. */
const char *mgcp_client_name(const struct mgcp_client *mgcp)
{
if (!mgcp)
return "(null)";
if (mgcp->actual.description)
return mgcp->actual.description;
else
return mgcp_client_endpoint_domain(mgcp);
}
/*! Return typical cmp result, comparing a to b.
* Return 0 if a == b, -1 if a < b, 1 if a > b; comparing all members of ptmap in turn. */
int ptmap_cmp(const struct ptmap *a, const struct ptmap *b)
{
int rc;
if (a == b)
return 0;
if (!a)
return -1;
if (!b)
return 1;
rc = OSMO_CMP(a->codec, b->codec);
if (rc)
return rc;
return OSMO_CMP(a->pt, b->pt);
}
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