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rtpengine/daemon/sdp.c

3213 lines
94 KiB

#include "sdp.h"
#include <glib.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <math.h>
#include <stdbool.h>
#include "compat.h"
#include "call.h"
#include "log.h"
#include "str.h"
#include "call.h"
#include "crypto.h"
#include "dtls.h"
#include "rtp.h"
#include "ice.h"
#include "socket.h"
#include "call_interfaces.h"
#include "rtplib.h"
#include "codec.h"
enum attr_id {
ATTR_OTHER = 0,
ATTR_RTCP,
ATTR_CANDIDATE,
ATTR_ICE,
ATTR_ICE_LITE,
ATTR_ICE_OPTIONS,
ATTR_ICE_UFRAG,
ATTR_ICE_PWD,
ATTR_CRYPTO,
ATTR_INACTIVE,
ATTR_SENDRECV,
ATTR_SENDONLY,
ATTR_RECVONLY,
ATTR_RTCP_MUX,
ATTR_GROUP,
ATTR_MID,
ATTR_FINGERPRINT,
ATTR_SETUP,
ATTR_RTPMAP,
ATTR_FMTP,
ATTR_IGNORE,
ATTR_RTPENGINE,
ATTR_PTIME,
ATTR_RTCP_FB,
ATTR_T38FAXVERSION,
ATTR_T38FAXUDPEC,
ATTR_T38FAXUDPECDEPTH,
ATTR_T38FAXUDPFECMAXSPAN,
ATTR_T38FAXMAXDATAGRAM,
ATTR_T38FAXMAXIFP,
ATTR_T38FAXFILLBITREMOVAL,
ATTR_T38FAXTRANSCODINGMMR,
ATTR_T38FAXTRANSCODINGJBIG,
ATTR_T38FAXRATEMANAGEMENT,
/* this is a block of attributes, which are only needed to carry attributes
* from `sdp_media` to `call_media`structure,
* and needs later processing in `sdp_create()`. */
ATTR_T38MAXBITRATE,
ATTR_T38FAXMAXBUFFER,
ATTR_MAXPTIME,
ATTR_TLS_ID,
ATTR_END_OF_CANDIDATES,
};
// make sure g_int_hash can be used
static_assert(sizeof(gint) == sizeof(enum attr_id), "sizeof enum attr_id wrong");
struct sdp_connection {
str s;
struct network_address address;
unsigned int parsed:1;
};
INLINE unsigned int attr_id_hash(const enum attr_id *e) {
int i = *e;
return g_int_hash(&i);
}
INLINE gboolean attr_id_eq(const enum attr_id *a, const enum attr_id *b) {
return *a == *b;
}
TYPED_GQUEUE(attributes, struct sdp_attribute)
TYPED_GHASHTABLE(attr_id_ht, enum attr_id, struct sdp_attribute, attr_id_hash, attr_id_eq, NULL, NULL)
TYPED_GHASHTABLE(attr_list_ht, enum attr_id, attributes_q, attr_id_hash, attr_id_eq, NULL, g_queue_free)
TYPED_GHASHTABLE_LOOKUP_INSERT(attr_list_ht, NULL, attributes_q_new)
struct sdp_attributes {
attributes_q list;
/* GHashTable *name_hash; */
/* GHashTable *name_lists_hash; */
attr_list_ht id_lists_hash;
attr_id_ht id_hash;
};
TYPED_GQUEUE(sdp_media, struct sdp_media)
struct sdp_session {
str s;
sdp_origin origin;
str session_name;
str session_timing; /* t= */
struct sdp_connection connection;
struct session_bandwidth bandwidth;
struct sdp_attributes attributes;
sdp_media_q media_streams;
};
struct sdp_media {
struct sdp_session *session;
str s;
str media_type_str;
str port;
str transport;
str formats; /* space separated */
long int port_num;
int port_count;
struct sdp_connection connection;
const char *c_line_pos; // XXX to be obsoleted
struct session_bandwidth bandwidth;
struct sdp_attributes attributes;
str_slice_q format_list; /* list of slice-alloc'd str objects */
enum media_type media_type_id;
int media_sdp_id;
unsigned int legacy_osrtp:1;
};
struct attribute_rtcp {
long int port_num;
struct network_address address;
};
struct attribute_candidate {
str component_str;
str transport_str;
str priority_str;
str address_str;
str port_str;
str typ_str;
str type_str;
str raddr_str;
str related_address_str;
str rport_str;
str related_port_str;
struct ice_candidate cand_parsed;
unsigned int parsed:1;
};
struct attribute_crypto {
str tag_str;
str crypto_suite_str;
str key_params_str;
str key_base64_str;
str lifetime_str;
str mki_str;
unsigned int tag;
/* XXX use struct crypto_params for these below? */
const struct crypto_suite *crypto_suite;
str master_key;
str salt;
char key_salt_buf[SRTP_MAX_MASTER_KEY_LEN + SRTP_MAX_MASTER_SALT_LEN];
uint64_t lifetime;
unsigned char mki[256];
unsigned int mki_len;
unsigned int unencrypted_srtcp:1,
unencrypted_srtp:1,
unauthenticated_srtp:1;
};
struct attribute_ssrc {
str id_str;
str attr_str;
uint32_t id;
str attr;
str value;
};
struct attribute_group {
enum {
GROUP_OTHER = 0,
GROUP_BUNDLE,
} semantics;
};
struct attribute_fingerprint {
str hash_func_str;
str fingerprint_str;
const struct dtls_hash_func *hash_func;
unsigned char fingerprint[DTLS_MAX_DIGEST_LEN];
};
struct attribute_setup {
str s;
enum {
SETUP_UNKNOWN = 0,
SETUP_ACTPASS,
SETUP_ACTIVE,
SETUP_PASSIVE,
SETUP_HOLDCONN,
} value;
};
struct attribute_rtpmap {
str payload_type_str;
str encoding_str;
str clock_rate_str;
rtp_payload_type rtp_pt;
};
struct attribute_rtcp_fb {
str payload_type_str;
str value;
unsigned int payload_type;
};
struct attribute_fmtp {
str payload_type_str;
str format_parms_str;
unsigned int payload_type;
};
struct attribute_t38faxratemanagement {
enum {
RM_UNKNOWN = 0,
RM_LOCALTCF,
RM_TRANSFERREDTCF,
} rm;
};
struct attribute_t38faxudpec {
enum {
EC_UNKNOWN = 0,
EC_NONE,
EC_REDUNDANCY,
EC_FEC,
} ec;
};
struct attribute_t38faxudpecdepth {
str minred_str;
str maxred_str;
int minred;
int maxred;
};
enum attribute_other {
ATTR_OTHER_UNKNOWN = 0,
ATTR_OTHER_EXTMAP,
};
struct sdp_attribute {
/* example: a=rtpmap:8 PCMA/8000 */
str full_line; /* including a= and \r\n */ // XXX to be obsoleted
str param; /* "PCMA/8000" */
struct sdp_attribute_strs strs;
enum attr_id attr;
union {
struct attribute_rtcp rtcp;
struct attribute_candidate candidate;
struct attribute_crypto crypto;
struct attribute_ssrc ssrc;
struct attribute_group group;
struct attribute_fingerprint fingerprint;
struct attribute_setup setup;
struct attribute_rtpmap rtpmap;
struct attribute_rtcp_fb rtcp_fb;
struct attribute_fmtp fmtp;
struct attribute_t38faxudpec t38faxudpec;
int i;
struct attribute_t38faxudpecdepth t38faxudpecdepth;
struct attribute_t38faxratemanagement t38faxratemanagement;
enum attribute_other other;
};
};
struct sdp_attr {
struct sdp_attribute_strs strs;
enum attr_id attr;
enum attribute_other other;
};
/**
* Globaly visible variables for this file.
*/
static char __id_buf[6*2 + 1]; // 6 hex encoded characters
const str rtpe_instance_id = STR_CONST(__id_buf);
/**
* Declarations for inner functions/helpers.
*/
static struct sdp_attr *sdp_attr_dup(const struct sdp_attribute *c);
static void attr_free(struct sdp_attribute *p);
static void attr_insert(struct sdp_attributes *attrs, struct sdp_attribute *attr);
static struct call_media *sdp_out_set_source_media_address(struct call_media *media,
struct packet_stream *rtp_ps,
struct sdp_ng_flags *flags,
const endpoint_t **sdp_address);
static void sdp_out_add_bandwidth(GString *out, struct call_monologue *monologue,
struct call_media *media);
static void sdp_out_add_media_connection(GString *out, struct call_media *media,
struct packet_stream *rtp_ps, const sockaddr_t *address, sdp_ng_flags *flags);
static void sdp_out_original_media_attributes(GString *out, struct call_media *media,
const endpoint_t *address, struct call_media *source_media,
struct packet_stream *rtp_ps, sdp_ng_flags *flags);
/**
* Checks whether an attribute removal request exists for a given session level.
* `attr_name` must be without `a=`.
*/
static bool sdp_manipulate_remove(struct sdp_manipulations * sdp_manipulations, const str * attr_name) {
/* no need for checks, if not given in flags */
if (!sdp_manipulations)
return false;
if (!attr_name || !attr_name->len)
return false;
str_case_ht ht = sdp_manipulations->rem_commands;
if (t_hash_table_is_set(ht) && t_hash_table_lookup(ht, attr_name))
return true;
ilog(LOG_DEBUG, "Cannot insert: '" STR_FORMAT "' because prevented by SDP manipulations (remove)",
STR_FMT(attr_name));
return false;
}
/**
* Checks whether an attribute removal request exists for a given session level.
* `attr_name` must be without `a=`.
*/
static bool sdp_manipulate_remove_c(const char *attr_name, const sdp_ng_flags *flags, enum media_type media_type) {
struct sdp_manipulations *sdp_manipulations = sdp_manipulations_get_by_id(flags, media_type);
return sdp_manipulate_remove(sdp_manipulations, STR_PTR(attr_name));
}
/**
* Adds values into a requested session level (global, audio, video)
*/
static void sdp_manipulations_add(GString *s, struct sdp_manipulations * sdp_manipulations) {
if (!sdp_manipulations)
return;
str_q * q_ptr = &sdp_manipulations->add_commands;
for (__auto_type l = q_ptr->head; l; l = l->next)
{
str * attr_value = l->data;
g_string_append_len(s, "a=", 2);
g_string_append_len(s, attr_value->s, strlen(attr_value->s));
g_string_append_len(s, "\r\n", 2);
}
}
/**
* Substitute values for a requested session level (global, audio, video).
* `attr_name` must be without `a=`.
*/
static str *sdp_manipulations_subst(struct sdp_manipulations * sdp_manipulations,
const str * attr_name) {
if (!sdp_manipulations)
return NULL;
str_case_value_ht ht = sdp_manipulations->subst_commands;
str * cmd_subst_value = t_hash_table_is_set(ht) ? t_hash_table_lookup(ht, attr_name) : NULL;
if (cmd_subst_value)
ilog(LOG_DEBUG, "Substituting '" STR_FORMAT "' with '" STR_FORMAT "' due to SDP manipulations",
STR_FMT(attr_name), STR_FMT(cmd_subst_value));
return cmd_subst_value;
}
static void append_str_attr_to_gstring(GString *s, const str * name, const str * value,
const sdp_ng_flags *flags, enum media_type media_type);
static void append_attr_int_to_gstring(GString *s, const char * value, const int additional,
const sdp_ng_flags *flags, enum media_type media_type);
static void append_tagged_attr_to_gstring(GString *s, const char * name, const str *tag, const str * value,
const sdp_ng_flags *flags, enum media_type media_type);
static void append_int_tagged_attr_to_gstring(GString *s, const char * name, unsigned int tag, const str * value,
const sdp_ng_flags *flags, enum media_type media_type);
void sdp_append_str_attr(GString *s, const sdp_ng_flags *flags, enum media_type media_type,
const str *name, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
g_autoptr(GString) gs = g_string_new("");
g_string_vprintf(gs, fmt, ap);
va_end(ap);
append_str_attr_to_gstring(s, name, &STR_GS(gs), flags, media_type);
}
INLINE void append_attr_to_gstring(GString *s, const char * name, const str * value,
const sdp_ng_flags *flags, enum media_type media_type)
{
append_str_attr_to_gstring(s, STR_PTR(name), value, flags, media_type);
}
INLINE struct sdp_attribute *attr_get_by_id(struct sdp_attributes *a, enum attr_id id) {
return t_hash_table_lookup(a->id_hash, &id);
}
INLINE attributes_q *attr_list_get_by_id(struct sdp_attributes *a, enum attr_id id) {
return t_hash_table_lookup(a->id_lists_hash, &id);
}
static struct sdp_attribute *attr_get_by_id_m_s(struct sdp_media *m, enum attr_id id) {
struct sdp_attribute *a;
a = attr_get_by_id(&m->attributes, id);
if (a)
return a;
return attr_get_by_id(&m->session->attributes, id);
}
static int __parse_address(sockaddr_t *out, str *network_type, str *address_type, str *address) {
sockfamily_t *af;
if (network_type) {
if (network_type->len != 2)
return -1;
if (memcmp(network_type->s, "IN", 2)
&& memcmp(network_type->s, "in", 2))
return -1;
}
if (!address_type->len) {
if (sockaddr_parse_any_str(out, address))
return -1;
return 0;
}
af = get_socket_family_rfc(address_type);
if (sockaddr_parse_str(out, af, address))
return -1;
return 0;
}
static int parse_address(struct network_address *address) {
return __parse_address(&address->parsed, &address->network_type,
&address->address_type, &address->address);
}
#define EXTRACT_TOKEN(field) do { if (!str_token_sep(&output->field, value_str, ' ')) return -1; } while (0)
#define EXTRACT_NETWORK_ADDRESS_NP(field) \
do { EXTRACT_TOKEN(field.network_type); \
EXTRACT_TOKEN(field.address_type); \
EXTRACT_TOKEN(field.address); } while (0)
#define EXTRACT_NETWORK_ADDRESS(field) \
do { EXTRACT_NETWORK_ADDRESS_NP(field); \
if (parse_address(&output->field)) return -1; } while (0)
#define EXTRACT_NETWORK_ADDRESS_NF(field) \
do { EXTRACT_NETWORK_ADDRESS_NP(field); \
if (parse_address(&output->field)) { \
output->field.parsed.family = get_socket_family_enum(SF_IP4); \
output->field.parsed.ipv4.s_addr = 1; \
} } while (0)
#define PARSE_INIT str v_str = output->strs.value; str *value_str = &v_str
static int parse_origin(str *value_str, sdp_origin *output) {
if (output->parsed)
return -1;
EXTRACT_TOKEN(username);
EXTRACT_TOKEN(session_id);
EXTRACT_TOKEN(version_str);
EXTRACT_NETWORK_ADDRESS_NF(address);
output->version_num = strtoull(output->version_str.s, NULL, 10);
output->parsed = 1;
return 0;
}
static int parse_connection(str *value_str, struct sdp_connection *output) {
if (output->parsed)
return -1;
output->s = *value_str;
EXTRACT_NETWORK_ADDRESS(address);
output->parsed = 1;
return 0;
}
static int parse_media(str *value_str, struct sdp_media *output) {
char *ep;
str *sp;
EXTRACT_TOKEN(media_type_str);
EXTRACT_TOKEN(port);
EXTRACT_TOKEN(transport);
output->formats = *value_str;
output->media_type_id = codec_get_type(&output->media_type_str);
output->port_num = strtol(output->port.s, &ep, 10);
if (ep == output->port.s)
return -1;
if (output->port_num < 0 || output->port_num > 0xffff)
return -1;
if (*ep == '/') {
output->port_count = atoi(ep + 1);
if (output->port_count <= 0)
return -1;
if (output->port_count > 10) /* unsupported */
return -1;
}
else
output->port_count = 1;
/* to split the "formats" list into tokens, we abuse some vars */
str formats = output->formats;
str format;
while (str_token_sep(&format, &formats, ' ')) {
sp = str_slice_dup(&format);
t_queue_push_tail(&output->format_list, sp);
}
return 0;
}
static void attrs_init(struct sdp_attributes *a) {
t_queue_init(&a->list);
/* a->name_hash = g_hash_table_new(str_hash, str_equal); */
a->id_hash = attr_id_ht_new();
/* a->name_lists_hash = g_hash_table_new_full(str_hash, str_equal,
NULL, (GDestroyNotify) g_queue_free); */
a->id_lists_hash = attr_list_ht_new();
}
static void attr_insert(struct sdp_attributes *attrs, struct sdp_attribute *attr) {
t_queue_push_tail(&attrs->list, attr);
if (!t_hash_table_lookup(attrs->id_hash, &attr->attr))
t_hash_table_insert(attrs->id_hash, &attr->attr, attr);
attributes_q *attr_queue = attr_list_ht_lookup_insert(attrs->id_lists_hash, &attr->attr);
t_queue_push_tail(attr_queue, attr);
/* g_hash_table_insert(attrs->name_hash, &attr->name, attr); */
/* if (attr->key.s)
g_hash_table_insert(attrs->name_hash, &attr->key, attr); */
/* attr_queue = g_hash_table_lookup_queue_new(attrs->name_lists_hash, &attr->name);
g_queue_push_tail(attr_queue, attr); */
}
static int parse_attribute_group(struct sdp_attribute *output) {
output->attr = ATTR_GROUP;
output->group.semantics = GROUP_OTHER;
if (output->strs.value.len >= 7 && !strncmp(output->strs.value.s, "BUNDLE ", 7))
output->group.semantics = GROUP_BUNDLE;
return 0;
}
static int parse_attribute_crypto(struct sdp_attribute *output) {
char *endp;
struct attribute_crypto *c;
int salt_key_len, enc_salt_key_len;
int b64_state = 0;
unsigned int b64_save = 0;
gsize ret;
str s;
uint32_t u32;
const char *err;
output->attr = ATTR_CRYPTO;
PARSE_INIT;
EXTRACT_TOKEN(crypto.tag_str);
EXTRACT_TOKEN(crypto.crypto_suite_str);
EXTRACT_TOKEN(crypto.key_params_str);
c = &output->crypto;
c->tag = strtoul(c->tag_str.s, &endp, 10);
err = "invalid 'tag'";
if (endp == c->tag_str.s)
goto error;
c->crypto_suite = crypto_find_suite(&c->crypto_suite_str);
err = "unknown crypto suite";
if (!c->crypto_suite)
goto error;
salt_key_len = c->crypto_suite->master_key_len
+ c->crypto_suite->master_salt_len;
enc_salt_key_len = ceil((double) salt_key_len * 4.0/3.0);
err = "invalid key parameter length";
if (c->key_params_str.len < 7 + enc_salt_key_len)
goto error;
err = "unknown key method";
if (strncasecmp(c->key_params_str.s, "inline:", 7))
goto error;
c->key_base64_str = c->key_params_str;
str_shift(&c->key_base64_str, 7);
ret = g_base64_decode_step(c->key_base64_str.s, enc_salt_key_len,
(guchar *) c->key_salt_buf, &b64_state, &b64_save);
// flush b64_state needed for AES-192: 36+2; AES-256: 45+1;
if (enc_salt_key_len % 4) {
ret += g_base64_decode_step("==", 4 - (enc_salt_key_len % 4),
(guchar *) c->key_salt_buf + ret, &b64_state, &b64_save);
}
err = "invalid base64 encoding";
if (ret != salt_key_len)
goto error;
c->master_key = STR_LEN(c->key_salt_buf, c->crypto_suite->master_key_len);
c->salt = STR_LEN(c->master_key.s + c->master_key.len, c->crypto_suite->master_salt_len);
c->lifetime_str = c->key_params_str;
str_shift(&c->lifetime_str, 7 + enc_salt_key_len);
// skip past base64 padding
if (enc_salt_key_len % 4 == 2) {
str_shift_cmp(&c->lifetime_str, "==");
} else if (enc_salt_key_len % 4 == 3) {
str_shift_cmp(&c->lifetime_str, "=");
}
if (c->lifetime_str.len >= 2) {
err = "invalid key parameter syntax";
if (c->lifetime_str.s[0] != '|')
goto error;
str_shift(&c->lifetime_str, 1);
if (!str_chr_str(&c->mki_str, &c->lifetime_str, '|')) {
if (str_chr(&c->lifetime_str, ':')) {
c->mki_str = c->lifetime_str;
c->lifetime_str = STR_NULL;
}
}
else {
c->lifetime_str.len = c->mki_str.s - c->lifetime_str.s;
str_shift(&c->mki_str, 1);
}
}
else
c->lifetime_str = STR_NULL;
if (c->lifetime_str.s) {
if (c->lifetime_str.len >= 3 && !memcmp(c->lifetime_str.s, "2^", 2)) {
c->lifetime = strtoull(c->lifetime_str.s + 2, NULL, 10);
err = "invalid key lifetime";
if (!c->lifetime || c->lifetime >= 64)
goto error;
c->lifetime = 1ULL << c->lifetime;
}
else
c->lifetime = strtoull(c->lifetime_str.s, NULL, 10);
err = "invalid key lifetime";
if (!c->lifetime || c->lifetime > c->crypto_suite->srtp_lifetime
#ifdef STRICT_SDES_KEY_LIFETIME
|| c->lifetime > c->crypto_suite->srtcp_lifetime
#endif
)
goto error;
}
if (c->mki_str.s) {
err = "invalid MKI specification";
if (!str_chr_str(&s, &c->mki_str, ':'))
goto error;
u32 = htonl(strtoul(c->mki_str.s, NULL, 10));
c->mki_len = strtoul(s.s + 1, NULL, 10);
err = "MKI too long";
if (c->mki_len > sizeof(c->mki))
goto error;
memset(c->mki, 0, c->mki_len);
if (sizeof(u32) >= c->mki_len)
memcpy(c->mki, ((void *) &u32) + (sizeof(u32) - c->mki_len), c->mki_len);
else
memcpy(c->mki + (c->mki_len - sizeof(u32)), &u32, sizeof(u32));
}
while (str_token_sep(&s, value_str, ' ')) {
if (!str_cmp(&s, "UNENCRYPTED_SRTCP"))
c->unencrypted_srtcp = 1;
else if (!str_cmp(&s, "UNENCRYPTED_SRTP"))
c->unencrypted_srtp = 1;
else if (!str_cmp(&s, "UNAUTHENTICATED_SRTP"))
c->unauthenticated_srtp = 1;
}
return 0;
error:
ilog(LOG_ERROR, "Failed to parse a=crypto attribute, ignoring: %s", err);
output->attr = ATTR_IGNORE;
return 0;
}
static int parse_attribute_rtcp(struct sdp_attribute *output) {
if (!output->strs.value.s)
goto err;
output->attr = ATTR_RTCP;
PARSE_INIT;
str portnum;
if (!str_token_sep(&portnum, value_str, ' '))
goto err;
output->rtcp.port_num = str_to_i(&portnum, 0);
if (output->rtcp.port_num <= 0 || output->rtcp.port_num > 0xffff) {
output->rtcp.port_num = 0;
goto err;
}
if (value_str->len)
EXTRACT_NETWORK_ADDRESS(rtcp.address);
return 0;
err:
ilog(LOG_WARN, "Failed to parse a=rtcp attribute, ignoring");
output->attr = ATTR_IGNORE;
return 0;
}
static int parse_attribute_candidate(struct sdp_attribute *output, bool extended) {
char *ep;
struct attribute_candidate *c;
output->attr = ATTR_CANDIDATE;
c = &output->candidate;
PARSE_INIT;
EXTRACT_TOKEN(candidate.cand_parsed.foundation);
EXTRACT_TOKEN(candidate.component_str);
EXTRACT_TOKEN(candidate.transport_str);
EXTRACT_TOKEN(candidate.priority_str);
EXTRACT_TOKEN(candidate.address_str);
EXTRACT_TOKEN(candidate.port_str);
EXTRACT_TOKEN(candidate.typ_str);
EXTRACT_TOKEN(candidate.type_str);
c->cand_parsed.component_id = strtoul(c->component_str.s, &ep, 10);
if (ep == c->component_str.s)
return -1;
c->cand_parsed.transport = get_socket_type(&c->transport_str);
if (!c->cand_parsed.transport)
return 0;
c->cand_parsed.priority = strtoul(c->priority_str.s, &ep, 10);
if (ep == c->priority_str.s)
return -1;
if (sockaddr_parse_any_str(&c->cand_parsed.endpoint.address, &c->address_str))
return 0;
c->cand_parsed.endpoint.port = strtoul(c->port_str.s, &ep, 10);
if (ep == c->port_str.s)
return -1;
if (str_cmp(&c->typ_str, "typ"))
return -1;
c->cand_parsed.type = ice_candidate_type(&c->type_str);
if (!c->cand_parsed.type)
return 0;
if (ice_has_related(c->cand_parsed.type)) {
// XXX guaranteed to be in order even with extended syntax?
EXTRACT_TOKEN(candidate.raddr_str);
EXTRACT_TOKEN(candidate.related_address_str);
EXTRACT_TOKEN(candidate.rport_str);
EXTRACT_TOKEN(candidate.related_port_str);
if (str_cmp(&c->raddr_str, "raddr"))
return -1;
if (str_cmp(&c->rport_str, "rport"))
return -1;
if (sockaddr_parse_any_str(&c->cand_parsed.related.address, &c->related_address_str))
return 0;
c->cand_parsed.related.port = strtoul(c->related_port_str.s, &ep, 10);
if (ep == c->related_port_str.s)
return -1;
}
if (extended) {
while (true) {
str field, value;
if (!str_token_sep(&field, value_str, ' '))
break;
if (!str_token_sep(&value, value_str, ' '))
break;
if (!str_cmp(&field, "ufrag"))
c->cand_parsed.ufrag = value;
}
}
c->parsed = 1;
return 0;
}
// 0 = success
// -1 = error
// 1 = parsed ok but unsupported candidate type
int sdp_parse_candidate(struct ice_candidate *cand, const str *s) {
struct sdp_attribute attr = {
.strs = {
.value = *s,
},
};
if (parse_attribute_candidate(&attr, true))
return -1;
if (!attr.candidate.parsed)
return 1;
*cand = attr.candidate.cand_parsed;
return 0;
}
static int parse_attribute_fingerprint(struct sdp_attribute *output) {
unsigned char *c;
int i;
output->attr = ATTR_FINGERPRINT;
PARSE_INIT;
EXTRACT_TOKEN(fingerprint.hash_func_str);
EXTRACT_TOKEN(fingerprint.fingerprint_str);
output->fingerprint.hash_func = dtls_find_hash_func(&output->fingerprint.hash_func_str);
if (!output->fingerprint.hash_func)
return -1;
assert(sizeof(output->fingerprint.fingerprint) >= output->fingerprint.hash_func->num_bytes);
c = (unsigned char *) output->fingerprint.fingerprint_str.s;
for (i = 0; i < output->fingerprint.hash_func->num_bytes; i++) {
if (c[0] >= '0' && c[0] <= '9')
output->fingerprint.fingerprint[i] = c[0] - '0';
else if (c[0] >= 'a' && c[0] <= 'f')
output->fingerprint.fingerprint[i] = c[0] - 'a' + 10;
else if (c[0] >= 'A' && c[0] <= 'F')
output->fingerprint.fingerprint[i] = c[0] - 'A' + 10;
else
return -1;
output->fingerprint.fingerprint[i] <<= 4;
if (c[1] >= '0' && c[1] <= '9')
output->fingerprint.fingerprint[i] |= c[1] - '0';
else if (c[1] >= 'a' && c[1] <= 'f')
output->fingerprint.fingerprint[i] |= c[1] - 'a' + 10;
else if (c[1] >= 'A' && c[1] <= 'F')
output->fingerprint.fingerprint[i] |= c[1] - 'A' + 10;
else
return -1;
if (c[2] != ':')
goto done;
c += 3;
}
return -1;
done:
if (++i != output->fingerprint.hash_func->num_bytes)
return -1;
return 0;
}
static int parse_attribute_setup(struct sdp_attribute *output) {
output->attr = ATTR_SETUP;
if (!str_cmp(&output->strs.value, "actpass"))
output->setup.value = SETUP_ACTPASS;
else if (!str_cmp(&output->strs.value, "active"))
output->setup.value = SETUP_ACTIVE;
else if (!str_cmp(&output->strs.value, "passive"))
output->setup.value = SETUP_PASSIVE;
else if (!str_cmp(&output->strs.value, "holdconn"))
output->setup.value = SETUP_HOLDCONN;
return 0;
}
static int parse_attribute_rtcp_fb(struct sdp_attribute *output) {
struct attribute_rtcp_fb *a;
output->attr = ATTR_RTCP_FB;
a = &output->rtcp_fb;
PARSE_INIT;
EXTRACT_TOKEN(rtcp_fb.payload_type_str);
a->value = *value_str;
if (!str_cmp(&a->payload_type_str, "*"))
a->payload_type = -1;
else {
a->payload_type = str_to_i(&a->payload_type_str, -1);
if (a->payload_type == -1)
return -1;
}
return 0;
}
static int parse_attribute_rtpmap(struct sdp_attribute *output) {
char *ep;
struct attribute_rtpmap *a;
rtp_payload_type *pt;
output->attr = ATTR_RTPMAP;
PARSE_INIT;
EXTRACT_TOKEN(rtpmap.payload_type_str);
EXTRACT_TOKEN(rtpmap.encoding_str);
a = &output->rtpmap;
pt = &a->rtp_pt;
pt->encoding_with_params = a->encoding_str;
pt->payload_type = strtoul(a->payload_type_str.s, &ep, 10);
if (ep == a->payload_type_str.s)
return -1;
if (!str_chr_str(&a->clock_rate_str, &a->encoding_str, '/'))
return -1;
pt->encoding = a->encoding_str;
pt->encoding.len -= a->clock_rate_str.len;
str_shift(&a->clock_rate_str, 1);
pt->channels = 1;
if (str_chr_str(&pt->encoding_parameters, &a->clock_rate_str, '/')) {
a->clock_rate_str.len -= pt->encoding_parameters.len;
str_shift(&pt->encoding_parameters, 1);
if (pt->encoding_parameters.len) {
int channels = strtol(pt->encoding_parameters.s, &ep, 10);
if (channels && (!ep || ep == pt->encoding_parameters.s + pt->encoding_parameters.len))
pt->channels = channels;
}
}
if (!a->clock_rate_str.len)
return -1;
pt->clock_rate = strtoul(a->clock_rate_str.s, &ep, 10);
if (ep && ep != a->clock_rate_str.s + a->clock_rate_str.len)
return -1;
return 0;
}
static int parse_attribute_fmtp(struct sdp_attribute *output) {
struct attribute_fmtp *a;
output->attr = ATTR_FMTP;
a = &output->fmtp;
PARSE_INIT;
EXTRACT_TOKEN(fmtp.payload_type_str);
a->format_parms_str = *value_str;
a->payload_type = str_to_i(&a->payload_type_str, -1);
if (a->payload_type == -1)
return -1;
return 0;
}
static int parse_attribute_int(struct sdp_attribute *output, enum attr_id attr_id, int defval) {
output->attr = attr_id;
output->i = str_to_i(&output->strs.value, defval);
return 0;
}
// XXX combine this with parse_attribute_setup ?
static int parse_attribute_t38faxudpec(struct sdp_attribute *output) {
output->attr = ATTR_T38FAXUDPEC;
switch (__csh_lookup(&output->strs.value)) {
case CSH_LOOKUP("t38UDPNoEC"):
output->t38faxudpec.ec = EC_NONE;
break;
case CSH_LOOKUP("t38UDPRedundancy"):
output->t38faxudpec.ec = EC_REDUNDANCY;
break;
case CSH_LOOKUP("t38UDPFEC"):
output->t38faxudpec.ec = EC_FEC;
break;
default:
output->t38faxudpec.ec = EC_UNKNOWN;
break;
}
return 0;
}
// XXX combine this with parse_attribute_setup ?
static int parse_attribute_t38faxratemanagement(struct sdp_attribute *output) {
output->attr = ATTR_T38FAXRATEMANAGEMENT;
switch (__csh_lookup(&output->strs.value)) {
case CSH_LOOKUP("localTFC"):
output->t38faxratemanagement.rm = RM_LOCALTCF;
break;
case CSH_LOOKUP("transferredTCF"):
output->t38faxratemanagement.rm = RM_TRANSFERREDTCF;
break;
default:
output->t38faxratemanagement.rm = RM_UNKNOWN;
break;
}
return 0;
}
static int parse_attribute_t38faxudpecdepth(struct sdp_attribute *output) {
struct attribute_t38faxudpecdepth *a;
output->attr = ATTR_T38FAXUDPECDEPTH;
a = &output->t38faxudpecdepth;
PARSE_INIT;
EXTRACT_TOKEN(t38faxudpecdepth.minred_str);
a->maxred_str = *value_str;
a->minred = str_to_i(&a->minred_str, 0);
a->maxred = str_to_i(&a->maxred_str, -1);
return 0;
}
static int parse_attribute(struct sdp_attribute *a) {
int ret;
a->strs.name = a->strs.line_value;
if (str_chr_str(&a->strs.value, &a->strs.name, ':')) {
a->strs.name.len -= a->strs.value.len;
a->strs.value.s++;
a->strs.value.len--;
a->strs.key = a->strs.name;
if (str_chr_str(&a->param, &a->strs.value, ' ')) {
a->strs.key.len += 1 +
(a->strs.value.len - a->param.len);
a->param.s++;
a->param.len--;
if (!a->param.len)
a->param.s = NULL;
}
else
a->strs.key.len += 1 + a->strs.value.len;
}
ret = 0;
switch (__csh_lookup(&a->strs.name)) {
case CSH_LOOKUP("mid"):
a->attr = ATTR_MID;
break;
case CSH_LOOKUP("rtcp"):
ret = parse_attribute_rtcp(a);
break;
case CSH_LOOKUP("fmtp"):
ret = parse_attribute_fmtp(a);
break;
case CSH_LOOKUP("group"):
ret = parse_attribute_group(a);
break;
case CSH_LOOKUP("setup"):
ret = parse_attribute_setup(a);
break;
case CSH_LOOKUP("ptime"):
a->attr = ATTR_PTIME;
break;
case CSH_LOOKUP("crypto"):
ret = parse_attribute_crypto(a);
break;
case CSH_LOOKUP("extmap"):
a->other = ATTR_OTHER_EXTMAP;
break;
case CSH_LOOKUP("rtpmap"):
ret = parse_attribute_rtpmap(a);
break;
case CSH_LOOKUP("ice-pwd"):
a->attr = ATTR_ICE_PWD;
break;
case CSH_LOOKUP("ice-lite"):
a->attr = ATTR_ICE_LITE;
break;
case CSH_LOOKUP("inactive"):
a->attr = ATTR_INACTIVE;
break;
case CSH_LOOKUP("sendrecv"):
a->attr = ATTR_SENDRECV;
break;
case CSH_LOOKUP("sendonly"):
a->attr = ATTR_SENDONLY;
break;
case CSH_LOOKUP("recvonly"):
a->attr = ATTR_RECVONLY;
break;
case CSH_LOOKUP("rtcp-mux"):
a->attr = ATTR_RTCP_MUX;
break;
case CSH_LOOKUP("candidate"):
ret = parse_attribute_candidate(a, false);
break;
case CSH_LOOKUP("ice-ufrag"):
a->attr = ATTR_ICE_UFRAG;
break;
case CSH_LOOKUP("rtpengine"):
a->attr = ATTR_RTPENGINE;
break;
case CSH_LOOKUP("ice-options"):
a->attr = ATTR_ICE_OPTIONS;
break;
case CSH_LOOKUP("fingerprint"):
ret = parse_attribute_fingerprint(a);
break;
case CSH_LOOKUP("tls-id"):
a->attr = ATTR_TLS_ID;
break;
case CSH_LOOKUP("ice-mismatch"):
a->attr = ATTR_ICE;
break;
case CSH_LOOKUP("remote-candidates"):
a->attr = ATTR_ICE;
break;
case CSH_LOOKUP("end-of-candidates"):
a->attr = ATTR_END_OF_CANDIDATES;
break;
case CSH_LOOKUP("rtcp-fb"):
ret = parse_attribute_rtcp_fb(a);
break;
case CSH_LOOKUP("T38FaxVersion"):
ret = parse_attribute_int(a, ATTR_T38FAXVERSION, -1);
break;
case CSH_LOOKUP("T38FaxUdpEC"):
ret = parse_attribute_t38faxudpec(a);
break;
case CSH_LOOKUP("T38FaxUdpECDepth"):
ret = parse_attribute_t38faxudpecdepth(a);
break;
case CSH_LOOKUP("T38FaxUdpFECMaxSpan"):
ret = parse_attribute_int(a, ATTR_T38FAXUDPFECMAXSPAN, 0);
break;
case CSH_LOOKUP("T38FaxMaxDatagram"):
ret = parse_attribute_int(a, ATTR_T38FAXMAXDATAGRAM, -1);
break;
case CSH_LOOKUP("T38FaxMaxIFP"):
ret = parse_attribute_int(a, ATTR_T38FAXMAXIFP, -1);
break;
case CSH_LOOKUP("T38FaxFillBitRemoval"):
a->attr = ATTR_T38FAXFILLBITREMOVAL;
break;
case CSH_LOOKUP("T38FaxTranscodingMMR"):
a->attr = ATTR_T38FAXTRANSCODINGMMR;
break;
case CSH_LOOKUP("T38FaxTranscodingJBIG"):
a->attr = ATTR_T38FAXTRANSCODINGJBIG;
break;
case CSH_LOOKUP("T38FaxRateManagement"):
ret = parse_attribute_t38faxratemanagement(a);
break;
case CSH_LOOKUP("T38MaxBitRate"):
a->attr = ATTR_T38MAXBITRATE;
break;
case CSH_LOOKUP("T38FaxMaxBuffer"):
a->attr = ATTR_T38FAXMAXBUFFER;
break;
case CSH_LOOKUP("maxptime"):
a->attr = ATTR_MAXPTIME;
break;
}
return ret;
}
int sdp_parse(str *body, sdp_sessions_q *sessions, const sdp_ng_flags *flags) {
str b;
struct sdp_session *session = NULL;
struct sdp_media *media = NULL;
const char *errstr;
struct sdp_attributes *attrs;
struct sdp_attribute *attr;
int media_sdp_id = 0;
b = *body;
while (b.len >= 2) {
if (!rtpe_config.reject_invalid_sdp) {
if (b.s[0] == '\n' || b.s[0] == '\r') {
body->len = b.s - body->s;
break;
}
}
char line_code = b.s[0];
errstr = "Missing '=' sign";
if (b.s[1] != '=')
goto error;
str full_line;
str_token(&full_line, &b, '\n');
if (full_line.s[full_line.len - 1] == '\r')
full_line.len--;
errstr = "SDP doesn't start with a session definition";
if (!session && line_code != 'v') {
if (!flags->fragment)
goto error;
else
goto new_session; // allowed for trickle ICE SDP fragments
}
str value = full_line;
str_shift(&value, 2); // removes `v=` etc
full_line.len = b.s - full_line.s; // include \r\n
switch (line_code) {
case 'v':
errstr = "Error in v= line";
if (value.len != 1) {
abort();
goto error;
}
if (value.s[0] != '0') {
abort();
goto error;
}
new_session:
session = g_slice_alloc0(sizeof(*session));
t_queue_init(&session->media_streams);
attrs_init(&session->attributes);
t_queue_push_tail(sessions, session);
media = NULL;
session->s = full_line;
RESET_BANDWIDTH(session->bandwidth, -1);
break;
case 'o':
errstr = "o= line found within media section";
if (media)
goto error;
errstr = "Error parsing o= line";
if (parse_origin(&value, &session->origin))
goto error;
break;
case 'm':
if (media && !media->c_line_pos)
media->c_line_pos = full_line.s;
media = g_slice_alloc0(sizeof(*media));
media->session = session;
attrs_init(&media->attributes);
errstr = "Error parsing m= line";
if (parse_media(&value, media))
goto error;
t_queue_push_tail(&session->media_streams, media);
media->s = full_line;
RESET_BANDWIDTH(media->bandwidth, -1);
media->media_sdp_id = media_sdp_id++;
break;
case 'c':
errstr = "Error parsing c= line";
if (parse_connection(&value,
media ? &media->connection : &session->connection))
goto error;
break;
case 'a':
if (media && !media->c_line_pos)
media->c_line_pos = full_line.s;
attr = g_slice_alloc0(sizeof(*attr));
attr->full_line = full_line;
attr->strs.line_value = value;
if (parse_attribute(attr)) {
attr_free(attr);
break;
}
attrs = media ? &media->attributes : &session->attributes;
attr_insert(attrs, attr);
break;
case 'b':
if (media && !media->c_line_pos)
media->c_line_pos = full_line.s;
/* RR:0 */
if (value.len < 4)
break;
/* AS, RR, RS */
if (!memcmp(value.s, "AS:", 3)) {
*(media ? &media->bandwidth.as : &session->bandwidth.as) = strtol((value.s + 3), NULL, 10);
}
else if (!memcmp(value.s, "RR:", 3)) {
*(media ? &media->bandwidth.rr : &session->bandwidth.rr) = strtol((value.s + 3), NULL, 10);
}
else if (!memcmp(value.s, "RS:", 3)) {
*(media ? &media->bandwidth.rs : &session->bandwidth.rs) = strtol((value.s + 3), NULL, 10);
}
else if (!memcmp(value.s, "TIAS:", 5)) {
*(media ? &media->bandwidth.tias : &session->bandwidth.tias) = strtol((value.s + 5), NULL, 10);
}
/* CT has only session level */
else if (!memcmp(value.s, "CT:", 3)) {
session->bandwidth.ct = strtol((value.s + 3), NULL, 10);
}
break;
case 'k':
if (media && !media->c_line_pos)
media->c_line_pos = full_line.s;
break;
case 's':
errstr = "s= line found within media section";
if (media)
goto error;
session->session_name = value;
break;
case 't':
errstr = "t= line found within media section";
if (media)
goto error;
session->session_timing = value;
break;
case 'i':
case 'u':
case 'e':
case 'p':
case 'r':
case 'z':
break;
default:
errstr = "Unknown SDP line type found";
goto error;
}
errstr = "SDP doesn't start with a valid session definition";
if (!session)
goto error;
// XXX to be obsoleted
str *adj_s = media ? &media->s : &session->s;
adj_s->len = b.s - adj_s->s;
}
return 0;
error:
ilog(LOG_WARNING, "Error parsing SDP at offset %zu: %s", (size_t) (b.s - body->s), errstr);
sdp_sessions_clear(sessions);
return -1;
}
static void attr_free(struct sdp_attribute *p) {
g_slice_free1(sizeof(*p), p);
}
static void free_attributes(struct sdp_attributes *a) {
/* g_hash_table_destroy(a->name_hash); */
t_hash_table_destroy(a->id_hash);
/* g_hash_table_destroy(a->name_lists_hash); */
t_hash_table_destroy(a->id_lists_hash);
t_queue_clear_full(&a->list, attr_free);
}
static void media_free(struct sdp_media *media) {
free_attributes(&media->attributes);
str_slice_q_clear_full(&media->format_list);
g_slice_free1(sizeof(*media), media);
}
static void session_free(struct sdp_session *session) {
t_queue_clear_full(&session->media_streams, media_free);
free_attributes(&session->attributes);
g_slice_free1(sizeof(*session), session);
}
void sdp_sessions_clear(sdp_sessions_q *sessions) {
t_queue_clear_full(sessions, session_free);
}
static int fill_endpoint(struct endpoint *ep, const struct sdp_media *media, sdp_ng_flags *flags,
struct network_address *address, long int port)
{
struct sdp_session *session = media->session;
if (!flags->trust_address) {
if (is_addr_unspecified(&flags->parsed_received_from)) {
if (__parse_address(&flags->parsed_received_from, NULL, &flags->received_from_family,
&flags->received_from_address))
return -1;
}
ep->address = flags->parsed_received_from;
}
else if (address && !is_addr_unspecified(&address->parsed))
ep->address = address->parsed;
else if (media->connection.parsed)
ep->address = media->connection.address.parsed;
else if (session->connection.parsed)
ep->address = session->connection.address.parsed;
else
return -1;
ep->port = port;
return 0;
}
static int __rtp_payload_types(struct stream_params *sp, struct sdp_media *media)
{
GHashTable *ht_rtpmap, *ht_fmtp, *ht_rtcp_fb;
struct sdp_attribute *attr;
int ret = 0;
if (!proto_is_rtp(sp->protocol))
return 0;
/* first go through a=rtpmap and build a hash table of attrs */
ht_rtpmap = g_hash_table_new(g_int_hash, g_int_equal);
attributes_q *q = attr_list_get_by_id(&media->attributes, ATTR_RTPMAP);
for (__auto_type ql = q ? q->head : NULL; ql; ql = ql->next) {
rtp_payload_type *pt;
attr = ql->data;
pt = &attr->rtpmap.rtp_pt;
g_hash_table_insert(ht_rtpmap, &pt->payload_type, pt);
}
// do the same for a=fmtp
ht_fmtp = g_hash_table_new(g_int_hash, g_int_equal);
q = attr_list_get_by_id(&media->attributes, ATTR_FMTP);
for (__auto_type ql = q ? q->head : NULL; ql; ql = ql->next) {
attr = ql->data;
g_hash_table_insert(ht_fmtp, &attr->fmtp.payload_type, &attr->fmtp.format_parms_str);
}
// do the same for a=rtcp-fb
ht_rtcp_fb = g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL, (GDestroyNotify) g_queue_free);
q = attr_list_get_by_id(&media->attributes, ATTR_RTCP_FB);
for (__auto_type ql = q ? q->head : NULL; ql; ql = ql->next) {
attr = ql->data;
/* rtcp-fb attributes applied on all payload types, must be added via generic attributes */
if (attr->rtcp_fb.payload_type == -1) {
struct sdp_attr *ac = sdp_attr_dup(attr);
t_queue_push_tail(&sp->generic_attributes, ac);
}
GQueue *rq = g_hash_table_lookup_queue_new(ht_rtcp_fb, GINT_TO_POINTER(attr->rtcp_fb.payload_type), NULL);
g_queue_push_tail(rq, &attr->rtcp_fb.value);
}
/* then go through the format list and associate */
for (__auto_type ql = media->format_list.head; ql; ql = ql->next) {
char *ep;
str *s;
unsigned int i;
rtp_payload_type *pt;
const rtp_payload_type *ptl, *ptrfc;
s = ql->data;
i = (unsigned int) strtoul(s->s, &ep, 10);
if (ep == s->s || i > 127)
goto error;
/* first look in rtpmap for a match, then check RFC types,
* else fall back to an "unknown" type */
ptrfc = rtp_get_rfc_payload_type(i);
ptl = g_hash_table_lookup(ht_rtpmap, &i);
pt = g_slice_alloc0(sizeof(*pt));
if (ptl)
*pt = *ptl;
else if (ptrfc)
*pt = *ptrfc;
else
pt->payload_type = i;
s = g_hash_table_lookup(ht_fmtp, &i);
if (s)
pt->format_parameters = *s;
else
pt->format_parameters = STR_EMPTY;
GQueue *rq = g_hash_table_lookup(ht_rtcp_fb, GINT_TO_POINTER(i));
if (rq) {
// steal the list contents and free the list
pt->rtcp_fb = *rq;
g_queue_init(rq);
g_hash_table_remove(ht_rtcp_fb, GINT_TO_POINTER(i)); // frees `rq`
}
// fill in ptime
if (sp->ptime)
pt->ptime = sp->ptime;
else if (!pt->ptime && ptrfc)
pt->ptime = ptrfc->ptime;
codec_init_payload_type(pt, sp->type_id);
codec_store_add_raw(&sp->codecs, pt);
}
goto out;
error:
ret = -1;
goto out;
out:
g_hash_table_destroy(ht_rtpmap);
g_hash_table_destroy(ht_fmtp);
g_hash_table_destroy(ht_rtcp_fb);
return ret;
}
static void __sdp_ice(struct stream_params *sp, struct sdp_media *media) {
struct sdp_attribute *attr;
struct attribute_candidate *ac;
struct ice_candidate *cand;
bool end_of_candidates = (attr_get_by_id_m_s(media, ATTR_END_OF_CANDIDATES));
attr = attr_get_by_id_m_s(media, ATTR_ICE_UFRAG);
if (!attr)
return;
sp->ice_ufrag = attr->strs.value;
SP_SET(sp, ICE);
attributes_q *q = attr_list_get_by_id(&media->attributes, ATTR_CANDIDATE);
if (!q)
goto no_cand;
for (__auto_type ql = q->head; ql; ql = ql->next) {
attr = ql->data;
ac = &attr->candidate;
if (!ac->parsed)
continue;
cand = g_slice_alloc(sizeof(*cand));
*cand = ac->cand_parsed;
t_queue_push_tail(&sp->ice_candidates, cand);
}
no_cand:
if ((attr = attr_get_by_id_m_s(media, ATTR_ICE_OPTIONS))) {
if (str_str(&attr->strs.value, "trickle") >= 0)
SP_SET(sp, TRICKLE_ICE);
}
else if (is_trickle_ice_address(&sp->rtp_endpoint))
SP_SET(sp, TRICKLE_ICE);
/* set end_of_candidates flag both, when it's trickle ice or not */
if (end_of_candidates)
SP_SET(sp, END_OF_CANDIDATES);
/* unset end_of_candidates flag, if it's non trickle and no attribute given */
if (!SP_ISSET(sp, TRICKLE_ICE) && !end_of_candidates)
SP_CLEAR(sp, END_OF_CANDIDATES);
if (attr_get_by_id_m_s(media, ATTR_ICE_LITE))
SP_SET(sp, ICE_LITE_PEER);
attr = attr_get_by_id_m_s(media, ATTR_ICE_PWD);
if (attr)
sp->ice_pwd = attr->strs.value;
}
static void __sdp_t38(struct stream_params *sp, struct sdp_media *media) {
struct sdp_attribute *attr;
struct t38_options *to = &sp->t38_options;
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXVERSION);
if (attr)
to->version = attr->i;
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXUDPEC);
if (attr) {
if (attr->t38faxudpec.ec == EC_REDUNDANCY)
to->max_ec_entries = to->min_ec_entries = 3; // defaults
else if (attr->t38faxudpec.ec == EC_FEC) {
// defaults
to->max_ec_entries = to->min_ec_entries = 3;
to->fec_span = 3;
}
// else default to 0
}
else // no EC specified, defaults:
to->max_ec_entries = to->min_ec_entries = 3; // defaults
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXUDPECDEPTH);
if (attr) {
to->min_ec_entries = attr->t38faxudpecdepth.minred;
to->max_ec_entries = attr->t38faxudpecdepth.maxred;
}
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXUDPFECMAXSPAN);
if (attr)
to->fec_span = attr->i;
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXMAXDATAGRAM);
if (attr)
to->max_datagram = attr->i;
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXMAXIFP);
if (attr)
to->max_ifp = attr->i;
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXFILLBITREMOVAL);
if (attr && (!attr->strs.value.len || str_cmp(&attr->strs.value, "0")))
to->fill_bit_removal = 1;
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXTRANSCODINGMMR);
if (attr && (!attr->strs.value.len || str_cmp(&attr->strs.value, "0")))
to->transcoding_mmr = 1;
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXTRANSCODINGJBIG);
if (attr && (!attr->strs.value.len || str_cmp(&attr->strs.value, "0")))
to->transcoding_jbig = 1;
attr = attr_get_by_id(&media->attributes, ATTR_T38FAXRATEMANAGEMENT);
if (attr)
to->local_tcf = (attr->t38faxratemanagement.rm == RM_LOCALTCF) ? 1 : 0;
}
static void sp_free(struct stream_params *s) {
codec_store_cleanup(&s->codecs);
ice_candidates_free(&s->ice_candidates);
crypto_params_sdes_queue_clear(&s->sdes_params);
t_queue_clear_full(&s->generic_attributes, sdp_attr_free);
t_queue_clear_full(&s->all_attributes, sdp_attr_free);
g_slice_free1(sizeof(*s), s);
}
// Check the list for a legacy non-RFC OSRTP offer:
// Given m= lines must be alternating between one RTP and one SRTP m= line, with matching
// types between each pair.
// If found, rewrite the list to pretend that only the SRTP m=line was given, and mark
// the session media accordingly.
// TODO: should be handled by monologue_offer_answer, without requiring OSRTP-accept to be
// set for re-invites. SDP rewriting and skipping media sections should be handled by
// associating offer/answer media sections directly with each other, instead of requiring
// the indexing to be in order and instead of requiring all sections between monologue and sdp_media
// lists to be matching.
// returns: discard this `sp` yes/no
static bool legacy_osrtp_accept(struct stream_params *sp, sdp_streams_q *streams, sdp_media_list *media_link,
const sdp_ng_flags *flags, unsigned int *num)
{
if (!streams->tail)
return false;
if (!media_link || !media_link->prev)
return false;
struct stream_params *last = streams->tail->data;
if (!flags->osrtp_accept_legacy)
return false;
// protocols must be known
if (!sp->protocol)
return false;
if (!last->protocol)
return false;
// types must match
if (sp->type_id != last->type_id)
return false;
// we must be looking at RTP pairs
if (!sp->protocol->rtp)
return false;
if (!last->protocol->rtp)
return false;
// see if this is SRTP and the previous was RTP
if (sp->protocol->srtp && !last->protocol->srtp) {
// is this a non-rejected SRTP section?
if (sp->rtp_endpoint.port) {
// looks ok. remove the previous one and only retain this one. mark it as such.
t_queue_pop_tail(streams);
sp_free(last);
SP_SET(sp, LEGACY_OSRTP);
struct sdp_media *prev_media = media_link->prev->data;
prev_media->legacy_osrtp = 1;
sp->index--;
(*num)--;
return false;
}
// or is it a rejected SRTP with a non-rejected RTP counterpart?
if (!sp->rtp_endpoint.port && last->rtp_endpoint.port) {
// just throw the rejected SRTP section away
struct sdp_media *media = media_link->data;
media->legacy_osrtp = 1;
sp_free(sp);
return true;
}
}
// or is it reversed? this being RTP and the previous was SRTP
else if (!sp->protocol->srtp && last->protocol->srtp) {
// if the SRTP one is not rejected, throw away the RTP one and mark the SRTP one
if (last->rtp_endpoint.port) {
SP_SET(last, LEGACY_OSRTP);
SP_SET(last, LEGACY_OSRTP_REV);
struct sdp_media *media = media_link->data;
media->legacy_osrtp = 1;
sp_free(sp);
return true;
}
}
return false;
}
static struct sdp_attr *sdp_attr_dup(const struct sdp_attribute *c) {
struct sdp_attr *ac = g_new0(__typeof(*ac), 1);
ac->strs.name = call_str_cpy(&c->strs.name);
ac->strs.value = call_str_cpy(&c->strs.value);
ac->other = c->other;
ac->attr = c->attr;
return ac;
}
void sdp_attr_free(struct sdp_attr *c) {
g_free(c);
}
sdp_origin *sdp_orig_dup(const sdp_origin *orig) {
sdp_origin *copy = g_slice_alloc0(sizeof(*copy));
copy->username = call_str_cpy(&orig->username);
copy->session_id = call_str_cpy(&orig->session_id);
copy->version_str = call_str_cpy(&orig->version_str);
copy->version_num = orig->version_num;
copy->version_output_pos = orig->version_output_pos;
copy->parsed = orig->parsed;
/* struct network_address */
copy->address.network_type = call_str_cpy(&orig->address.network_type);
copy->address.address_type = call_str_cpy(&orig->address.address_type);
copy->address.address = call_str_cpy(&orig->address.address);
copy->address.parsed = orig->address.parsed;
return copy;
}
void sdp_orig_free(sdp_origin *o) {
g_slice_free1(sizeof(*o), o);
}
// Duplicate all attributes from the source (parsed SDP attributes list) into
// the destination (string-format attribute list)
static void sdp_attr_append(sdp_attr_q *dst, attributes_q *attrs) {
if (!attrs)
return;
for (__auto_type ll = attrs->head; ll; ll = ll->next) {
__auto_type attr = ll->data;
struct sdp_attr *ac = sdp_attr_dup(attr);
t_queue_push_tail(dst, ac);
}
}
// Duplicate all OTHER attributes from the source (parsed SDP attributes list) into
// the destination (string-format attribute list)
static void sdp_attr_append_other(sdp_attr_q *dst, struct sdp_attributes *src) {
sdp_attr_append(dst, attr_list_get_by_id(src, ATTR_OTHER));
}
/* XXX split this function up */
int sdp_streams(const sdp_sessions_q *sessions, sdp_streams_q *streams, sdp_ng_flags *flags) {
struct sdp_session *session;
struct sdp_media *media;
struct stream_params *sp;
const char *errstr;
unsigned int num = 0;
struct sdp_attribute *attr;
for (auto_iter(l, sessions->head); l; l = l->next) {
session = l->data;
/* carry some of session level attributes for a later usage, using flags
* e.g. usage in `__call_monologue_init_from_flags()` or direct usage
* in `sdp_create()`
*/
sdp_attr_append_other(&flags->generic_attributes, &session->attributes);
sdp_attr_append(&flags->all_attributes, &session->attributes.list);
/* set only for the first SDP session, to be able to re-use versioning
* for all the rest SDP sessions during replacements. See `sdp_version_check()` */
if (!flags->session_sdp_orig.parsed)
flags->session_sdp_orig = session->origin;
flags->session_sdp_name = session->session_name;
flags->session_bandwidth = session->bandwidth;
flags->session_timing = session->session_timing;
attr = attr_get_by_id(&session->attributes, ATTR_GROUP);
if (attr)
flags->session_group = attr->strs.value;
for (__auto_type k = session->media_streams.head; k; k = k->next) {
media = k->data;
sp = g_slice_alloc0(sizeof(*sp));
sp->index = ++num;
codec_store_init(&sp->codecs, NULL);
sp->media_sdp_id = media->media_sdp_id;
errstr = "No address info found for stream";
if (!flags->fragment
&& fill_endpoint(&sp->rtp_endpoint, media, flags, NULL, media->port_num))
goto error;
__sdp_ice(sp, media);
if (SP_ISSET(sp, ICE)) {
// ignore "received from" (SIP-source-address) when ICE is in use
flags->trust_address = 1;
}
/*
* pass important context parameters: sdp_media -> stream_params
*/
sp->consecutive_ports = media->port_count;
sp->num_ports = sp->consecutive_ports * 2; // only do *=2 for RTP streams?
sp->protocol_str = media->transport;
sp->protocol = transport_protocol(&media->transport);
sp->type = media->media_type_str;
sp->type_id = media->media_type_id;
memcpy(sp->direction, flags->direction, sizeof(sp->direction));
sp->desired_family = flags->address_family;
bf_set_clear(&sp->sp_flags, SP_FLAG_ASYMMETRIC, flags->asymmetric);
bf_set_clear(&sp->sp_flags, SP_FLAG_UNIDIRECTIONAL, flags->unidirectional);
bf_set_clear(&sp->sp_flags, SP_FLAG_STRICT_SOURCE, flags->strict_source);
bf_set_clear(&sp->sp_flags, SP_FLAG_MEDIA_HANDOVER, flags->media_handover);
/* b= (bandwidth), is parsed in sdp_parse() */
sp->media_session_bandiwdth = media->bandwidth;
// a=ptime
attr = attr_get_by_id(&media->attributes, ATTR_PTIME);
if (attr && attr->strs.value.s)
sp->ptime = str_to_i(&attr->strs.value, 0);
// a=maxptime
attr = attr_get_by_id(&media->attributes, ATTR_MAXPTIME);
if (attr && attr->strs.value.s)
sp->maxptime = str_to_i(&attr->strs.value, 0);
sp->format_str = media->formats;
errstr = "Invalid RTP payload types";
if (__rtp_payload_types(sp, media))
goto error;
/* a=crypto */
attributes_q *attrs = attr_list_get_by_id(&media->attributes, ATTR_CRYPTO);
for (__auto_type ll = attrs ? attrs->head : NULL; ll; ll = ll->next) {
attr = ll->data;
struct crypto_params_sdes *cps = g_slice_alloc0(sizeof(*cps));
t_queue_push_tail(&sp->sdes_params, cps);
cps->params.crypto_suite = attr->crypto.crypto_suite;
cps->params.mki_len = attr->crypto.mki_len;
if (cps->params.mki_len) {
cps->params.mki = malloc(cps->params.mki_len);
memcpy(cps->params.mki, attr->crypto.mki, cps->params.mki_len);
}
cps->tag = attr->crypto.tag;
assert(sizeof(cps->params.master_key) >= attr->crypto.master_key.len);
assert(sizeof(cps->params.master_salt) >= attr->crypto.salt.len);
memcpy(cps->params.master_key, attr->crypto.master_key.s,
attr->crypto.master_key.len);
memcpy(cps->params.master_salt, attr->crypto.salt.s,
attr->crypto.salt.len);
cps->params.session_params.unencrypted_srtp = attr->crypto.unencrypted_srtp;
cps->params.session_params.unencrypted_srtcp = attr->crypto.unencrypted_srtcp;
cps->params.session_params.unauthenticated_srtp = attr->crypto.unauthenticated_srtp;
}
sdp_attr_append_other(&sp->generic_attributes, &media->attributes);
sdp_attr_append(&sp->all_attributes, &media->attributes.list);
/* a=sendrecv/sendonly/recvonly/inactive */
SP_SET(sp, SEND);
SP_SET(sp, RECV);
if (attr_get_by_id_m_s(media, ATTR_RECVONLY))
SP_CLEAR(sp, SEND);
else if (attr_get_by_id_m_s(media, ATTR_SENDONLY))
SP_CLEAR(sp, RECV);
else if (attr_get_by_id_m_s(media, ATTR_INACTIVE))
{
SP_CLEAR(sp, RECV);
SP_CLEAR(sp, SEND);
}
/* a=setup */
attr = attr_get_by_id_m_s(media, ATTR_SETUP);
if (attr) {
if (attr->setup.value == SETUP_ACTPASS
|| attr->setup.value == SETUP_ACTIVE)
SP_SET(sp, SETUP_ACTIVE);
if (attr->setup.value == SETUP_ACTPASS
|| attr->setup.value == SETUP_PASSIVE)
SP_SET(sp, SETUP_PASSIVE);
}
/* a=fingerprint */
attr = attr_get_by_id_m_s(media, ATTR_FINGERPRINT);
if (attr && attr->fingerprint.hash_func) {
sp->fingerprint.hash_func = attr->fingerprint.hash_func;
memcpy(sp->fingerprint.digest, attr->fingerprint.fingerprint,
sp->fingerprint.hash_func->num_bytes);
sp->fingerprint.digest_len = sp->fingerprint.hash_func->num_bytes;
}
// a=tls-id
attr = attr_get_by_id_m_s(media, ATTR_TLS_ID);
if (attr)
sp->tls_id = attr->strs.value;
// OSRTP (RFC 8643)
if (sp->protocol && sp->protocol->rtp && !sp->protocol->srtp
&& sp->protocol->osrtp_proto)
{
if (sp->fingerprint.hash_func || sp->sdes_params.length)
sp->protocol = &transport_protocols[sp->protocol->osrtp_proto];
}
if (legacy_osrtp_accept(sp, streams, k, flags, &num))
continue;
// a=mid
attr = attr_get_by_id(&media->attributes, ATTR_MID);
if (attr)
sp->media_id = attr->strs.value;
// be ignorant about the contents
if (attr_get_by_id(&media->attributes, ATTR_RTCP_FB))
SP_SET(sp, RTCP_FB);
__sdp_t38(sp, media);
/* determine RTCP endpoint */
if (attr_get_by_id(&media->attributes, ATTR_RTCP_MUX))
SP_SET(sp, RTCP_MUX);
attr = attr_get_by_id(&media->attributes, ATTR_RTCP);
if (!attr || media->port_count != 1) {
SP_SET(sp, IMPLICIT_RTCP);
goto next;
}
if (attr->rtcp.port_num == sp->rtp_endpoint.port
&& !is_trickle_ice_address(&sp->rtp_endpoint))
{
SP_SET(sp, RTCP_MUX);
goto next;
}
errstr = "Invalid RTCP attribute";
if (fill_endpoint(&sp->rtcp_endpoint, media, flags, &attr->rtcp.address,
attr->rtcp.port_num))
goto error;
next:
t_queue_push_tail(streams, sp);
}
}
return 0;
error:
ilog(LOG_WARNING, "Failed to extract streams from SDP: %s", errstr);
g_slice_free1(sizeof(*sp), sp);
return -1;
}
void sdp_streams_clear(sdp_streams_q *q) {
t_queue_clear_full(q, sp_free);
}
static void print_format_str(GString *s, struct call_media *cm) {
if (!cm->format_str.s)
return;
g_string_append_len(s, cm->format_str.s, cm->format_str.len);
return;
}
static void print_codec_list(GString *s, struct call_media *media) {
if (!proto_is_rtp(media->protocol)) {
print_format_str(s, media);
return;
}
if (media->codecs.codec_prefs.length == 0) {
// legacy protocol, usage error, or allow-no-codec-media set. Print something and bail
g_string_append(s, "0");
return;
}
for (__auto_type l = media->codecs.codec_prefs.head; l; l = l->next) {
rtp_payload_type *pt = l->data;
if (l != media->codecs.codec_prefs.head)
g_string_append_c(s, ' ');
g_string_append_printf(s, "%u", pt->payload_type);
}
return;
}
static void insert_codec_parameters(GString *s, struct call_media *cm,
const sdp_ng_flags *flags)
{
for (__auto_type l = cm->codecs.codec_prefs.head; l; l = l->next)
{
rtp_payload_type *pt = l->data;
if (!pt->encoding_with_params.len)
continue;
/* rtpmap */
append_int_tagged_attr_to_gstring(s, "rtpmap", pt->payload_type, &pt->encoding_with_params,
flags, cm->type_id);
/* fmtp */
g_autoptr(GString) fmtp = NULL;
if (pt->codec_def && pt->codec_def->format_print) {
fmtp = pt->codec_def->format_print(pt); /* try appending list of parameters */
if (fmtp && fmtp->len)
append_int_tagged_attr_to_gstring(s, "fmtp", pt->payload_type,
&STR_GS(fmtp), flags, cm->type_id);
}
if (!fmtp && pt->format_parameters.len)
append_int_tagged_attr_to_gstring(s, "fmtp", pt->payload_type,
&pt->format_parameters, flags, cm->type_id);
/* rtcp-fb */
for (GList *k = pt->rtcp_fb.head; k; k = k->next) {
str *fb = k->data;
append_int_tagged_attr_to_gstring(s, "rtcp-fb", pt->payload_type, fb,
flags, cm->type_id);
}
}
}
void sdp_insert_media_attributes(GString *gs, union sdp_attr_print_arg a, const sdp_ng_flags *flags) {
// Look up the source media. We copy the source's attributes if there is only one source
// media. Otherwise we skip this step.
if (a.cm->media_subscriptions.length != 1)
return;
__auto_type sub = a.cm->media_subscriptions.head->data;
__auto_type sub_m = sub->media;
for (__auto_type l = sub_m->generic_attributes.head; l; l = l->next) {
__auto_type s = l->data;
if (s->other == ATTR_OTHER_EXTMAP && flags->strip_extmap && !MEDIA_ISSET(a.cm, PASSTHRU))
continue;
append_str_attr_to_gstring(gs, &s->strs.name, &s->strs.value, flags, a.cm->type_id);
}
}
void sdp_insert_monologue_attributes(GString *gs, union sdp_attr_print_arg a, const sdp_ng_flags *flags) {
// Look up the source monologue. This must be a single source monologue for all medias. If
// there's a mismatch or multiple source monologues, we skip this step.
struct call_monologue *source_ml = ml_medias_subscribed_to_single_ml(a.ml);
if (!source_ml)
return;
for (__auto_type l = source_ml->generic_attributes.head; l; l = l->next) {
__auto_type s = l->data;
if (s->other == ATTR_OTHER_EXTMAP && flags->strip_extmap)
continue;
append_str_attr_to_gstring(gs, &s->strs.name, &s->strs.value, flags, MT_UNKNOWN);
}
}
void sdp_insert_all_attributes(GString *s, struct call_media *media, struct sdp_ng_flags *flags) {
for (__auto_type l = media->all_attributes.head; l; l = l->next) {
__auto_type a = l->data;
// the one exception: skip this and then print it separately if it was present,
// so that we can print our own candidates first
if (a->attr == ATTR_END_OF_CANDIDATES)
continue;
append_str_attr_to_gstring(s, &a->strs.name, &a->strs.value, flags, media->type_id);
}
}
static int insert_ice_address(GString *s, stream_fd *sfd, const sdp_ng_flags *flags) {
if (!is_addr_unspecified(&flags->media_address))
sockaddr_print_gstring(s, &flags->media_address);
else
call_stream_address(s, sfd->stream, SAF_ICE, sfd->local_intf, false);
g_string_append_printf(s, " %u", sfd->socket.local.port);
return 0;
}
static int insert_raddr_rport(GString *s, stream_fd *sfd, const sdp_ng_flags *flags) {
g_string_append(s, " raddr ");
if (!is_addr_unspecified(&flags->media_address))
sockaddr_print_gstring(s, &flags->media_address);
else
call_stream_address(s, sfd->stream, SAF_ICE, sfd->local_intf, false);
g_string_append(s, " rport ");
g_string_append_printf(s, "%u", sfd->socket.local.port);
return 0;
}
static void new_priority(struct call_media *media, enum ice_candidate_type type, unsigned int *tprefp,
unsigned int *lprefp)
{
unsigned int lpref, tpref;
uint32_t prio;
lpref = 0;
tpref = ice_type_preference(type);
prio = ice_priority_pref(tpref, lpref, 1);
candidate_q *cands = &media->ice_candidates;
for (__auto_type l = cands->head; l; l = l->next) {
__auto_type c = l->data;
if (c->priority <= prio && c->type == type
&& c->component_id == 1)
{
/* tpref should come out as 126 (if host) here, unless the client isn't following
* the RFC, in which case we must adapt */
tpref = ice_type_pref_from_prio(c->priority);
lpref = ice_local_pref_from_prio(c->priority);
if (lpref)
lpref--;
else {
/* we must deviate from the RFC recommended values */
if (tpref)
tpref--;
lpref = 65535;
}
prio = ice_priority_pref(tpref, lpref, 1);
}
}
*tprefp = tpref;
*lprefp = lpref;
}
static void insert_candidate(GString *s, stream_fd *sfd,
unsigned int type_pref, unsigned int local_pref, enum ice_candidate_type type,
const sdp_ng_flags *flags, struct call_media *media)
{
unsigned long priority;
struct packet_stream *ps = sfd->stream;
const struct local_intf *ifa = sfd->local_intf;
g_autoptr(GString) s_dst = g_string_new("");
if (local_pref == -1)
local_pref = ifa->unique_id;
priority = ice_priority_pref(type_pref, local_pref, ps->component);
g_string_append_printf(s_dst, "%u UDP %lu ", ps->component, priority);
insert_ice_address(s_dst, sfd, flags);
g_string_append(s_dst, " typ ");
g_string_append(s_dst, ice_candidate_type_str(type));
/* raddr and rport are required for non-host candidates: rfc5245 section-15.1 */
if(type != ICT_HOST)
insert_raddr_rport(s_dst, sfd, flags);
append_tagged_attr_to_gstring(s, "candidate", &ifa->ice_foundation, &STR_GS(s_dst), flags,
(media ? media->type_id : MT_UNKNOWN));
}
static void insert_sfd_candidates(GString *s, struct packet_stream *ps,
unsigned int type_pref, unsigned int local_pref, enum ice_candidate_type type,
const sdp_ng_flags *flags)
{
for (__auto_type l = ps->sfds.head; l; l = l->next) {
stream_fd *sfd = l->data;
insert_candidate(s, sfd, type_pref, local_pref, type, flags, ps->media);
if (local_pref != -1)
local_pref++;
}
}
static void insert_candidates(GString *s, struct packet_stream *rtp, struct packet_stream *rtcp,
const sdp_ng_flags *flags, struct call_media *source_media)
{
const struct local_intf *ifa;
struct call_media *media;
struct ice_agent *ag;
unsigned int type_pref, local_pref;
enum ice_candidate_type cand_type;
struct ice_candidate *cand;
media = rtp->media;
cand_type = ICT_HOST;
if (flags->ice_option == ICE_FORCE_RELAY)
cand_type = ICT_RELAY;
if (MEDIA_ISSET(media, PASSTHRU) && source_media)
new_priority(source_media, cand_type, &type_pref, &local_pref);
else {
type_pref = ice_type_preference(cand_type);
local_pref = -1;
}
ag = media->ice_agent;
if (ag && AGENT_ISSET(ag, COMPLETED)) {
ifa = rtp->selected_sfd->local_intf;
insert_candidate(s, rtp->selected_sfd, type_pref, ifa->unique_id, cand_type, flags, rtp->media);
if (rtcp) /* rtcp-mux only possible in answer */
insert_candidate(s, rtcp->selected_sfd, type_pref, ifa->unique_id, cand_type, flags,
rtp->media);
if (flags->opmode == OP_OFFER && AGENT_ISSET(ag, CONTROLLING)) {
g_auto(candidate_q) rc = TYPED_GQUEUE_INIT;
g_autoptr(GString) s_dst = g_string_new("");
/* prepare remote-candidates */
ice_remote_candidates(&rc, ag);
for (__auto_type l = rc.head; l; l = l->next) {
if (l != rc.head)
g_string_append(s_dst, " ");
cand = l->data;
g_string_append_printf(s_dst, "%lu %s %u", cand->component_id,
sockaddr_print_buf(&cand->endpoint.address), cand->endpoint.port);
}
append_attr_to_gstring(s, "remote-candidates", &STR_GS(s_dst), flags,
rtp->media->type_id);
}
return;
}
insert_sfd_candidates(s, rtp, type_pref, local_pref, cand_type, flags);
if (rtcp) /* rtcp-mux only possible in answer */
insert_sfd_candidates(s, rtcp, type_pref, local_pref, cand_type, flags);
}
static void insert_setup(GString *out, struct call_media *media, const sdp_ng_flags *flags,
bool add_default)
{
str actpass_str = STR_NULL;
if (MEDIA_ARESET2(media, SETUP_PASSIVE, SETUP_ACTIVE))
actpass_str = STR("actpass");
else if (MEDIA_ISSET(media, SETUP_PASSIVE))
actpass_str = STR("passive");
else if (MEDIA_ISSET(media, SETUP_ACTIVE))
actpass_str = STR("active");
else {
if (!add_default)
return;
actpass_str = STR("holdconn");
}
append_attr_to_gstring(out, "setup", &actpass_str, flags, media->type_id);
}
static void insert_dtls(GString *s, struct call_media *media, struct dtls_connection *dtls,
const sdp_ng_flags *flags)
{
unsigned char *p;
int i;
const struct dtls_hash_func *hf;
call_t *call = media->call;
if (!media->protocol || !media->protocol->srtp)
return;
if (!call->dtls_cert || !MEDIA_ISSET(media, DTLS) || MEDIA_ISSET(media, PASSTHRU))
return;
hf = media->fp_hash_func;
if (!hf)
hf = media->fingerprint.hash_func;
struct dtls_fingerprint *fp = NULL;
for (GList *l = call->dtls_cert->fingerprints.head; l; l = l->next) {
fp = l->data;
if (!hf)
break;
if (!strcasecmp(hf->name, fp->hash_func->name))
break;
fp = NULL;
}
if (!fp) // use first if no match
fp = call->dtls_cert->fingerprints.head->data;
hf = fp->hash_func;
media->fp_hash_func = hf;
assert(hf->num_bytes > 0);
/* a=setup: */
insert_setup(s, media, flags, true);
/* prepare fingerprint */
g_autoptr(GString) s_dst = g_string_new("");
g_string_append(s_dst, hf->name);
g_string_append(s_dst, " ");
p = fp->digest;
for (i = 0; i < hf->num_bytes; i++)
g_string_append_printf(s_dst, "%02X:", *p++);
g_string_truncate(s_dst, s_dst->len - 1);
append_attr_to_gstring(s, "fingerprint", &STR_GS(s_dst), flags, media->type_id);
if (dtls) {
/* prepare tls-id */
g_string_truncate(s_dst, 0);
p = dtls->tls_id;
for (i = 0; i < sizeof(dtls->tls_id); i++)
g_string_append_printf(s_dst, "%02x", *p++);
append_attr_to_gstring(s, "tls-id", &STR_GS(s_dst), flags, media->type_id);
}
}
static void insert_crypto1(GString *s, struct call_media *media, struct crypto_params_sdes *cps,
const sdp_ng_flags *flags)
{
char b64_buf[((SRTP_MAX_MASTER_KEY_LEN + SRTP_MAX_MASTER_SALT_LEN) / 3 + 1) * 4 + 4];
char *p;
int state = 0, save = 0, i;
unsigned long long ull;
if (!cps->params.crypto_suite || !MEDIA_ISSET(media, SDES) || MEDIA_ISSET(media, PASSTHRU))
return;
g_autoptr(GString) s_dst = g_string_new("");
p = b64_buf;
p += g_base64_encode_step((unsigned char *) cps->params.master_key,
cps->params.crypto_suite->master_key_len, 0,
p, &state, &save);
p += g_base64_encode_step((unsigned char *) cps->params.master_salt,
cps->params.crypto_suite->master_salt_len, 0,
p, &state, &save);
p += g_base64_encode_close(0, p, &state, &save);
if (!flags->sdes_pad) {
// truncate trailing ==
while (p > b64_buf && p[-1] == '=')
p--;
}
g_string_append(s_dst, cps->params.crypto_suite->name);
g_string_append(s_dst, " inline:");
g_string_append_len(s_dst, b64_buf, p - b64_buf);
if (flags->sdes_lifetime)
g_string_append(s_dst, "|2^31");
if (cps->params.mki_len) {
ull = 0;
for (i = 0; i < cps->params.mki_len && i < sizeof(ull); i++)
ull |= (unsigned long long) cps->params.mki[cps->params.mki_len - i - 1] << (i * 8);
g_string_append_printf(s_dst, "|%llu:%u", ull, cps->params.mki_len);
}
if (cps->params.session_params.unencrypted_srtp)
g_string_append(s_dst, " UNENCRYPTED_SRTP");
if (cps->params.session_params.unencrypted_srtcp)
g_string_append(s_dst, " UNENCRYPTED_SRTCP");
if (cps->params.session_params.unauthenticated_srtp)
g_string_append(s_dst, " UNAUTHENTICATED_SRTP");
append_int_tagged_attr_to_gstring(s, "crypto", cps->tag, &STR_GS(s_dst), flags, media->type_id);
}
static void insert_crypto(GString *s, struct call_media *media, const sdp_ng_flags *flags) {
if (!media->protocol || !media->protocol->srtp)
return;
for (__auto_type l = media->sdes_out.head; l; l = l->next)
insert_crypto1(s, media, l->data, flags);
}
static void insert_rtcp_attr(GString *s, struct packet_stream *ps, const sdp_ng_flags *flags,
struct call_media *media)
{
if (flags->no_rtcp_attr)
return;
g_autoptr(GString) s_dst = g_string_new("");
g_string_append_printf(s_dst, "%u", ps->selected_sfd->socket.local.port);
if (flags->full_rtcp_attr) {
g_string_append(s_dst, " IN ");
if (!is_addr_unspecified(&flags->media_address))
g_string_append_printf(s_dst, "%s %s",
flags->media_address.family->rfc_name,
sockaddr_print_buf(&flags->media_address));
else
call_stream_address(s_dst, ps, SAF_NG, NULL, false);
}
append_attr_to_gstring(s, "rtcp", &STR_GS(s_dst), flags, (media ? media->type_id : MT_UNKNOWN));
}
/**
* Handle sdp version replacements.
*/
static void sdp_version_replace(GString *s, sdp_origin *src_orig, sdp_origin *other_orig)
{
char version_str[64];
snprintf(version_str, sizeof(version_str), "%llu", src_orig->version_num);
size_t version_len = strlen(version_str);
if (!other_orig)
return;
other_orig->version_num = src_orig->version_num;
/* is our new value longer? */
if (version_len > other_orig->version_str.len) {
/* overwrite + insert */
g_string_overwrite_len(s, other_orig->version_output_pos, version_str, other_orig->version_str.len);
g_string_insert(s, other_orig->version_output_pos + other_orig->version_str.len, version_str + other_orig->version_str.len);
other_orig->version_str.len = version_len;
}
else {
/* overwrite + optional erase */
g_string_overwrite(s, other_orig->version_output_pos, version_str);
if (version_len < other_orig->version_str.len) {
g_string_erase(s, other_orig->version_output_pos + version_len, other_orig->version_str.len - version_len);
other_orig->version_str.len = version_len;
}
}
}
/**
* SDP session version manipulations.
*/
static void sdp_version_check(GString *s, struct call_monologue *monologue,
bool force_increase)
{
if (!monologue->session_last_sdp_orig)
return;
sdp_origin *origin = monologue->session_last_sdp_orig;
sdp_origin *other_origin = NULL;
struct media_subscription *ms = call_get_top_media_subscription(monologue);
if (ms && ms->monologue && ms->monologue->session_sdp_orig)
other_origin = ms->monologue->session_sdp_orig;
/* We really expect only a single session here, but we treat all the same regardless,
* and use the same version number on all of them */
/* First update all versions to match our single version */
sdp_version_replace(s, origin, other_origin);
/* Now check if we need to change the version actually.
* The version change will be forced with the 'force_increase',
* and it gets incremented, regardless whether:
* - we have no previously stored SDP,
* - we have previous SDP and it's equal to the current one */
if (!force_increase) {
if (!monologue->last_out_sdp)
goto dup;
if (g_string_equal(monologue->last_out_sdp, s))
return;
}
/* mismatch detected. increment version, update again, and store copy */
origin->version_num++;
sdp_version_replace(s, origin, other_origin);
if (monologue->last_out_sdp)
g_string_free(monologue->last_out_sdp, TRUE);
dup:
monologue->last_out_sdp = g_string_new_len(s->str, s->len);
}
const char *sdp_get_sendrecv(struct call_media *media) {
if (MEDIA_ARESET2(media, SEND, RECV))
return "sendrecv";
else if (MEDIA_ISSET(media, SEND))
return "sendonly";
else if (MEDIA_ISSET(media, RECV))
return "recvonly";
else
return "inactive";
}
/**
* Appends attributes to the output SDP.
* Includes substitute and remove SDP attribute manipulations.
*/
static void generic_append_attr_to_gstring(GString *s, const str * attr, char separator, const str * value,
const sdp_ng_flags *flags, enum media_type media_type)
{
struct sdp_manipulations *sdp_manipulations = sdp_manipulations_get_by_id(flags, media_type);
str * attr_subst = sdp_manipulations_subst(sdp_manipulations, attr);
/* first check if the originally present attribute is to be removed */
if (sdp_manipulate_remove(sdp_manipulations, attr))
return;
g_string_append(s, "a=");
/* then, if there remains something to be substituted, do that */
if (attr_subst)
g_string_append_len(s, attr_subst->s, attr_subst->len); // complete attribute
else {
gsize attr_start = s->len; // save beginning of complete attribute string
/* attr name */
g_string_append_len(s, attr->s, attr->len);
/* attr value */
if (value && value->len) {
g_string_append_c(s, separator);
g_string_append_len(s, value->s, value->len);
// check if the complete attribute string is marked for removal ...
str complete = STR_LEN(s->str + attr_start, s->len - attr_start);
if (sdp_manipulate_remove(sdp_manipulations, &complete))
{
// rewind and bail
g_string_truncate(s, attr_start - 2); // -2 for `a=`
return;
}
// ... or substitution
attr_subst = sdp_manipulations_subst(sdp_manipulations, &complete);
if (attr_subst) {
// rewind and replace
g_string_truncate(s, attr_start);
g_string_append_len(s, attr_subst->s, attr_subst->len);
}
}
}
g_string_append(s, "\r\n");
}
/* Appends attributes (`a=name:value`) to the output SDP */
static void append_str_attr_to_gstring(GString *s, const str * name, const str * value,
const sdp_ng_flags *flags, enum media_type media_type)
{
generic_append_attr_to_gstring(s, name, ':', value, flags, media_type);
}
/* Appends attributes (`a=name:tag value`) to the output SDP */
static void append_tagged_attr_to_gstring(GString *s, const char * name, const str *tag, const str * value,
const sdp_ng_flags *flags, enum media_type media_type)
{
if (sdp_manipulate_remove_c(name, flags, media_type))
return;
g_autoptr(GString) n = g_string_new(name);
g_string_append_c(n, ':');
g_string_append_len(n, tag->s, tag->len);
generic_append_attr_to_gstring(s, &STR_GS(n), ' ', value, flags, media_type);
}
/* Appends attributes (`a=name:uint value`) to the output SDP */
static void append_int_tagged_attr_to_gstring(GString *s, const char * name, unsigned int tag, const str * value,
const sdp_ng_flags *flags, enum media_type media_type)
{
if (sdp_manipulate_remove_c(name, flags, media_type))
return;
g_autoptr(GString) n = g_string_new(name);
g_string_append_printf(n, ":%u", tag);
generic_append_attr_to_gstring(s, &STR_GS(n), ' ', value, flags, media_type);
}
/* Appends attributes to the output SDP */
static void append_attr_int_to_gstring(GString *s, const char * name, const int value,
const sdp_ng_flags *flags, enum media_type media_type)
{
append_int_tagged_attr_to_gstring(s, name, value, NULL, flags, media_type);
}
static struct packet_stream *print_rtcp(GString *s, struct call_media *media, packet_stream_list *rtp_ps_link,
const sdp_ng_flags *flags)
{
struct packet_stream *ps = rtp_ps_link->data;
struct packet_stream *ps_rtcp = NULL;
if (ps->rtcp_sibling) {
ps_rtcp = ps->rtcp_sibling;
__auto_type rtcp_ps_link = rtp_ps_link->next;
if (!rtcp_ps_link)
return NULL;
assert(rtcp_ps_link->data == ps_rtcp);
}
if (proto_is_rtp(media->protocol)) {
if (MEDIA_ISSET(media, RTCP_MUX) &&
(flags->opmode == OP_ANSWER ||
flags->opmode == OP_PUBLISH ||
((flags->opmode == OP_OFFER || flags->opmode == OP_REQUEST) && flags->rtcp_mux_require) ||
IS_OP_OTHER(flags->opmode)))
{
insert_rtcp_attr(s, ps, flags, media);
append_attr_to_gstring(s, "rtcp-mux", NULL, flags, media->type_id);
ps_rtcp = NULL;
}
else if (ps_rtcp && flags->ice_option != ICE_FORCE_RELAY) {
insert_rtcp_attr(s, ps_rtcp, flags, media);
if (MEDIA_ISSET(media, RTCP_MUX))
append_attr_to_gstring(s, "rtcp-mux", NULL, flags, media->type_id);
}
}
else
ps_rtcp = NULL;
return ps_rtcp;
}
/* TODO: rework an appending of parameters in terms of sdp attribute manipulations */
static void print_sdp_media_section(GString *s, struct call_media *media,
const endpoint_t *address, struct call_media *source_media,
struct packet_stream *rtp_ps,
packet_stream_list *rtp_ps_link, sdp_ng_flags *flags)
{
struct call_monologue *monologue = media->monologue;
struct packet_stream *ps_rtcp = NULL;
bool inactive_media = (!address || !address->port || !rtp_ps->selected_sfd); /* audio is accepted? */
if (source_media) {
/* just print out all original values and attributes */
sdp_out_original_media_attributes(s, media, address, source_media, rtp_ps, flags);
return;
}
/* add actual media connection
* print zeroed address for the non accepted media, see RFC 3264 */
sdp_out_add_media_connection(s, media, rtp_ps, (inactive_media ? NULL : &address->address), flags);
/* add per media bandwidth */
sdp_out_add_bandwidth(s, monologue, media);
/* mid and label must be added even for inactive streams (see #1361 and #1362). */
if (media->media_id.s)
append_attr_to_gstring(s, "mid", &media->media_id, flags, media->type_id);
if (media->label.len && flags->siprec)
append_attr_to_gstring(s, "label", &media->label, flags, media->type_id);
/* nothing more to be printed for inactive stream (non-accepted media session) */
if (inactive_media)
return;
if (proto_is_rtp(media->protocol))
insert_codec_parameters(s, media, flags);
/* all unknown type attributes will be added here */
media->sdp_attr_print(s, media, flags);
/* print sendrecv */
if (!flags->original_sendrecv)
append_attr_to_gstring(s, sdp_get_sendrecv(media), NULL, flags,
media->type_id);
ps_rtcp = print_rtcp(s, media, rtp_ps_link, flags);
if (proto_is_rtp(media->protocol)) {
insert_crypto(s, media, flags);
insert_dtls(s, media, dtls_ptr(rtp_ps->selected_sfd), flags);
if (media->ptime)
append_attr_int_to_gstring(s, "ptime", media->ptime, flags,
media->type_id);
if (media->maxptime)
append_attr_int_to_gstring(s, "maxptime", media->maxptime, flags,
media->type_id);
}
if (MEDIA_ISSET(media, ICE) && media->ice_agent) {
append_attr_to_gstring(s, "ice-ufrag", &media->ice_agent->ufrag[1], flags,
media->type_id);
append_attr_to_gstring(s, "ice-pwd", &media->ice_agent->pwd[1], flags,
media->type_id);
}
if (MEDIA_ISSET(media, TRICKLE_ICE) && media->ice_agent) {
append_attr_to_gstring(s, "ice-options", &STR_CONST("trickle"), flags,
media->type_id);
}
if (MEDIA_ISSET(media, ICE)) {
insert_candidates(s, rtp_ps, ps_rtcp, flags, source_media);
}
if ((MEDIA_ISSET(media, TRICKLE_ICE) && media->ice_agent)) {
append_attr_to_gstring(s, "end-of-candidates", NULL, flags, media->type_id);
}
return;
}
static void sdp_out_add_origin(GString *out, struct call_monologue *monologue,
struct packet_stream *first_ps, sdp_ng_flags *flags)
{
struct call_monologue *ml = monologue;
/* for the offer/answer model or subscribe don't use the given monologues SDP,
* but try the one of the subscription, because the given monologue itself
* has likely no session attributes set yet */
struct media_subscription *ms = call_get_top_media_subscription(monologue);
if (ms && ms->monologue)
ml = ms->monologue;
/* orig username
* session_last_sdp_orig is stored on the other media always,
* so if origin is meant for the A media, then it is stored on the B one */
str * orig_username = (monologue->session_last_sdp_orig &&
(flags->replace_username || flags->replace_origin_full)) ?
&monologue->session_last_sdp_orig->username : &ml->session_sdp_orig->username;
/* orig session id */
str * orig_session_id = (monologue->session_last_sdp_orig && flags->replace_origin_full) ?
&monologue->session_last_sdp_orig->session_id : &ml->session_sdp_orig->session_id;
/* orig session ver
* replacement is handled later in sdp_create() based on SDP changes */
unsigned long long orig_session_version = ml->session_sdp_orig->version_num;
/* record origin version position for replacements
* + 4 - means: `o=` + 2 spaces between username and version / version and id */
ml->session_sdp_orig->version_output_pos = out->len + orig_username->len + orig_session_id->len + 4;
/* orig IP family and address */
str orig_address_type;
str orig_address;
if (!ms || flags->replace_origin || flags->replace_origin_full) {
/* replacing flags or PUBLISH */
orig_address_type = STR(first_ps->selected_sfd->local_intf->advertised_address.addr.family->rfc_name);
orig_address = STR(sockaddr_print_buf(&first_ps->selected_sfd->local_intf->advertised_address.addr));
} else {
orig_address_type = ml->session_sdp_orig->address.address_type;
orig_address = ml->session_sdp_orig->address.address;
}
/* print it to the output sdp */
g_string_append_printf(out,
"o="STR_FORMAT" "STR_FORMAT" %llu IN "STR_FORMAT" "STR_FORMAT"\r\n",
STR_FMT(orig_username),
STR_FMT(orig_session_id),
orig_session_version,
STR_FMT(&orig_address_type),
STR_FMT(&orig_address));
}
static void sdp_out_add_session_name(GString *out, struct call_monologue *monologue)
{
g_string_append(out, "s=");
/* PUBLISH exceptionally doesn't include sdp session name from SDP.
* The session name and other values should be copied only from a source SDP,
* if that is also a media source. For a publish request that's not the case. */
/* for the offer/answer model or subscribe don't use the given monologues SDP,
* but try the one of the subscription, because the given monologue itself
* has likely no session attributes set yet */
struct media_subscription *ms = call_get_top_media_subscription(monologue);
if (ms && ms->monologue)
{
/* if a session name was empty in the s= attr of the coming message,
* while processing this ml in `__call_monologue_init_from_flags()`,
* then just keep it empty. */
if (ms->monologue->sdp_session_name.len)
g_string_append_len(out, ms->monologue->sdp_session_name.s, ms->monologue->sdp_session_name.len);
}
else
g_string_append(out, rtpe_config.software_id);
g_string_append(out, "\r\n");
}
static void sdp_out_add_timing(GString *out, struct call_monologue *monologue)
{
/* sdp timing per session level */
g_string_append(out, "t=");
struct media_subscription *ms = call_get_top_media_subscription(monologue);
if (ms && ms->monologue && ms->monologue->sdp_session_timing.len)
g_string_append_len(out, ms->monologue->sdp_session_timing.s, ms->monologue->sdp_session_timing.len);
else
g_string_append(out, "0 0"); /* default */
g_string_append(out, "\r\n");
}
static void sdp_out_add_other(GString *out, struct call_monologue *monologue,
struct call_media *media,
sdp_ng_flags *flags)
{
bool media_has_ice = MEDIA_ISSET(media, ICE);
bool media_has_ice_lite_self = MEDIA_ISSET(media, ICE_LITE_SELF);
struct media_subscription *ms = call_get_top_media_subscription(monologue);
/* add loop protectio if required */
if (flags->loop_protect)
append_attr_to_gstring(out, "rtpengine", &rtpe_instance_id, flags, media->type_id);
/* ice-lite */
if (media_has_ice && media_has_ice_lite_self)
append_attr_to_gstring(out, "ice-lite", NULL, flags, media->type_id);
/* group */
if (ms && ms->monologue && ms->monologue->sdp_session_group.len && flags->ice_option == ICE_FORCE_RELAY)
append_attr_to_gstring(out, "group", &ms->monologue->sdp_session_group, flags, media->type_id);
/* carry other session level a= attributes to the outgoing SDP */
monologue->sdp_attr_print(out, monologue, flags);
/* ADD arbitrary SDP manipulations for a session sessions */
struct sdp_manipulations *sdp_manipulations = sdp_manipulations_get_by_id(flags, MT_UNKNOWN);
sdp_manipulations_add(out, sdp_manipulations);
}
static void sdp_out_add_bandwidth(GString *out, struct call_monologue *monologue,
struct call_media *media)
{
/* if there's a media given, only do look up the values for that one */
if (media) {
/* sdp bandwidth per media level */
struct media_subscription *ms = media->media_subscriptions.head ? media->media_subscriptions.head->data : NULL;
if (!ms || !ms->media)
return;
if (ms->media->sdp_media_bandwidth.as >= 0)
g_string_append_printf(out, "b=AS:%ld\r\n", ms->media->sdp_media_bandwidth.as);
if (ms->media->sdp_media_bandwidth.rr >= 0)
g_string_append_printf(out, "b=RR:%ld\r\n", ms->media->sdp_media_bandwidth.rr);
if (ms->media->sdp_media_bandwidth.rs >= 0)
g_string_append_printf(out, "b=RS:%ld\r\n", ms->media->sdp_media_bandwidth.rs);
if (ms->media->sdp_media_bandwidth.tias >= 0)
g_string_append_printf(out, "b=TIAS:%ld\r\n", ms->media->sdp_media_bandwidth.tias);
}
else {
/* sdp bandwidth per session/media level
* 0 value is supported (e.g. b=RR:0 and b=RS:0), to be able to disable rtcp */
struct media_subscription *ms = call_get_top_media_subscription(monologue);
if (!ms || !ms->monologue)
return;
if (ms->monologue->sdp_session_bandwidth.as >= 0)
g_string_append_printf(out, "b=AS:%ld\r\n", ms->monologue->sdp_session_bandwidth.as);
if (ms->monologue->sdp_session_bandwidth.rr >= 0)
g_string_append_printf(out, "b=RR:%ld\r\n", ms->monologue->sdp_session_bandwidth.rr);
if (ms->monologue->sdp_session_bandwidth.rs >= 0)
g_string_append_printf(out, "b=RS:%ld\r\n", ms->monologue->sdp_session_bandwidth.rs);
if (ms->monologue->sdp_session_bandwidth.ct >= 0)
g_string_append_printf(out, "b=CT:%ld\r\n", ms->monologue->sdp_session_bandwidth.ct);
if (ms->monologue->sdp_session_bandwidth.tias >= 0)
g_string_append_printf(out, "b=TIAS:%ld\r\n", ms->monologue->sdp_session_bandwidth.tias);
}
}
static void sdp_out_add_media_connection(GString *out, struct call_media *media,
struct packet_stream *rtp_ps, const sockaddr_t *address, sdp_ng_flags *flags)
{
if (!is_addr_unspecified(&flags->media_address))
address = &flags->media_address;
const char *media_conn_address = NULL;
const char *media_conn_address_type = NULL;
/* print zeroed address */
if (!address || (PS_ISSET(rtp_ps, ZERO_ADDR) && !MEDIA_ISSET(media, ICE))) {
if (!address) {
const struct intf_address *ifa_addr;
const struct local_intf *ifa;
if (rtp_ps->selected_sfd)
ifa = rtp_ps->selected_sfd->local_intf;
else
ifa = get_any_interface_address(rtp_ps->media->logical_intf, rtp_ps->media->desired_family);
ifa_addr = &ifa->spec->local_address;
media_conn_address_type = ifa_addr->addr.family->rfc_name;
media_conn_address = ifa_addr->addr.family->unspec_string;
}
else {
media_conn_address_type = address->family->rfc_name;
media_conn_address = address->family->unspec_string;
}
}
else {
media_conn_address_type = address->family->rfc_name;
media_conn_address = sockaddr_print_buf(address);
}
g_string_append_printf(out,
"c=IN %s %s\r\n",
media_conn_address_type,
media_conn_address);
}
/**
* Add OSRTP related media line.
*/
static void sdp_out_add_osrtp_media(GString *out, struct call_media *media,
const struct transport_protocol *prtp, const endpoint_t *address)
{
g_string_append_printf(out, "m=" STR_FORMAT " %d %s ",
STR_FMT(&media->type),
address ? address->port : 0,
prtp->name);
/* print codecs and add newline */
print_codec_list(out, media);
g_string_append_printf(out, "\r\n");
}
/**
* Add media line.
*/
static bool sdp_out_add_media(GString *out, struct call_media *media,
unsigned int port)
{
if (media->protocol)
g_string_append_printf(out, "m=" STR_FORMAT " %i %s ",
STR_FMT(&media->type),
port,
media->protocol->name);
else if (media->protocol_str.s)
g_string_append_printf(out, "m=" STR_FORMAT " %i " STR_FORMAT " ",
STR_FMT(&media->type),
port,
STR_FMT(&media->protocol_str));
else
return false;
/* print codecs and add newline */
print_codec_list(out, media);
g_string_append_printf(out, "\r\n");
return true;
}
static void sdp_out_handle_osrtp1(GString *out, struct call_media *media,
const endpoint_t *address, const struct transport_protocol *prtp,
struct packet_stream *rtp_ps, packet_stream_list *rtp_ps_link,
sdp_ng_flags *flags)
{
if (!prtp)
return;
if (MEDIA_ISSET(media, LEGACY_OSRTP) && !MEDIA_ISSET(media, LEGACY_OSRTP_REV))
/* generate rejected m= line for accepted legacy OSRTP */
sdp_out_add_osrtp_media(out, media, prtp, NULL);
else if(flags->osrtp_offer_legacy && (flags->opmode == OP_OFFER || flags->opmode == OP_REQUEST)) {
const struct transport_protocol *proto = media->protocol;
media->protocol = prtp;
sdp_out_add_osrtp_media(out, media, prtp, address);
/* print media level attributes */
print_sdp_media_section(out, media, address, NULL, rtp_ps, rtp_ps_link, flags);
media->protocol = proto;
}
}
static void sdp_out_handle_osrtp2(GString *out, struct call_media *media,
const struct transport_protocol *prtp)
{
if (!prtp)
return;
if (MEDIA_ISSET(media, LEGACY_OSRTP) && MEDIA_ISSET(media, LEGACY_OSRTP_REV))
/* generate rejected m= line for accepted legacy OSRTP */
sdp_out_add_osrtp_media(out, media, prtp, 0);
}
/**
* Adds original attributes into the media.
*/
static void sdp_out_original_media_attributes(GString *out, struct call_media *media,
const endpoint_t *address, struct call_media *source_media,
struct packet_stream *rtp_ps, sdp_ng_flags *flags)
{
sdp_out_add_media_connection(out, media, rtp_ps, &address->address, flags);
sdp_out_add_bandwidth(out, source_media->monologue, media);
sdp_insert_all_attributes(out, source_media, flags);
if (MEDIA_ISSET(source_media, ICE)) {
struct packet_stream *rtcp_ps = rtp_ps->rtcp_sibling;
/* TODO: is this a better or worse test than used in print_rtcp() ? */
if (rtcp_ps && (!rtcp_ps->selected_sfd || rtcp_ps->selected_sfd->socket.local.port == 0))
rtcp_ps = NULL;
insert_candidates(out, rtp_ps, rtcp_ps, flags, source_media);
if (MEDIA_ISSET(source_media, END_OF_CANDIDATES))
append_attr_to_gstring(out, "end-of-candidates", NULL, flags, media->type_id);
}
}
/**
* Should we just pass through the original SDP (mostly) unchanged,
* then we need to look up the source media.
*/
static struct call_media *sdp_out_set_source_media_address(struct call_media *media,
struct packet_stream *rtp_ps,
struct sdp_ng_flags *flags,
const endpoint_t **sdp_address)
{
struct call_media *source_media = NULL;
/* the port and address that goes into the SDP also depends on this */
if (sdp_address)
*sdp_address = rtp_ps->selected_sfd ? &rtp_ps->selected_sfd->socket.local : NULL;
struct media_subscription *ms = media->media_subscriptions.head ? media->media_subscriptions.head->data : NULL;
if (ms && ms->media) {
source_media = ms->media;
/* cases with message, force relay and pass through */
if (media->type_id == MT_MESSAGE || flags->ice_option == ICE_FORCE_RELAY || MEDIA_ISSET(media, PASSTHRU)) {
if (source_media->streams.head) {
__auto_type sub_ps = ms->media->streams.head->data;
if (sdp_address)
*sdp_address = &sub_ps->advertised_endpoint;
}
return source_media;
}
/* detect passthrough (cases where no RTP/SRTP spotted on both media sides).
* Doesn't require source_address to be changed to the original one (e.g. T.38 cases),
* since we still probably want to proxy media for them.
*/
else if (!proto_is_rtp(media->protocol) && !proto_is_rtp(source_media->protocol))
return source_media;
}
// handle special case: allow-no-codec-media
if (flags->allow_no_codec_media && media->codecs.codec_prefs.length == 0
&& proto_is_rtp(media->protocol))
{
// convert to rejected/removed stream
*sdp_address = NULL;
}
return NULL;
}
/**
* For the offer/answer model, SDP create will be triggered for the B monologue,
* which likely has empty paramaters (such as sdp origin, session name etc.), hence
* such parameters have to be taken from the A monologue (so from the subscription).
*
* For the rest of cases (publish, subscribe, janus etc.) this works as usual:
* given monologue is a monologue which is being processed.
*/
int sdp_create(str *out, struct call_monologue *monologue, sdp_ng_flags *flags)
{
const char *err = NULL;
GString *s = NULL;
const struct transport_protocol *prtp;
struct call_media *media = NULL;
struct packet_stream *first_ps = NULL;
err = "Need at least one media";
if (!monologue->medias->len)
goto err;
/* look for the first usable (non-rejected, non-empty) media and ps,
* thereby to determine session-level attributes, if any */
for (int i = 0; i < monologue->medias->len; i++) {
media = monologue->medias->pdata[i];
if (!media)
continue;
if (!media->streams.head)
continue;
first_ps = media->streams.head->data;
if (!first_ps->selected_sfd)
continue;
break;
}
err = "No usable packet stream";
if (!first_ps || !first_ps->selected_sfd)
goto err;
/* init new sdp */
s = g_string_new("v=0\r\n");
/* add origin including name and version */
sdp_out_add_origin(s, monologue, first_ps, flags);
/* add an actual sdp session name */
sdp_out_add_session_name(s, monologue);
/* don't set connection on the session level
* but instead per media, below */
/* add bandwidth control per session level */
sdp_out_add_bandwidth(s, monologue, NULL);
/* set timing to always be: 0 0 */
sdp_out_add_timing(s, monologue);
/* add other session level attributes */
sdp_out_add_other(s, monologue, media, flags);
/* print media sections */
for (unsigned int i = 0; i < monologue->medias->len; i++)
{
media = monologue->medias->pdata[i];
/* check call media existence */
err = "Empty media stream";
if (!media)
continue;
/* check streams existence */
err = "Zero length media stream";
if (!media->streams.length)
goto err;
__auto_type rtp_ps_link = media->streams.head;
struct packet_stream *rtp_ps = rtp_ps_link->data;
const endpoint_t *sdp_address;
struct call_media *source_media = sdp_out_set_source_media_address(media, rtp_ps, flags,
&sdp_address);
unsigned int port = sdp_address ? sdp_address->port : 0;
prtp = NULL;
if (media->protocol && media->protocol->srtp)
prtp = &transport_protocols[media->protocol->rtp_proto];
/* handle first OSRTP part */
sdp_out_handle_osrtp1(s, media, sdp_address, prtp, rtp_ps, rtp_ps_link, flags);
/* set: media type, port, protocol (e.g. RTP/SAVP) */
err = "Unknown media protocol";
if (!sdp_out_add_media(s, media, port))
goto err;
/* print media level attributes */
print_sdp_media_section(s, media, sdp_address, source_media, rtp_ps, rtp_ps_link, flags);
/* handle second OSRTP part */
sdp_out_handle_osrtp2(s, media, prtp);
/* ADD arbitrary SDP manipulations for audio/video media sessions */
struct sdp_manipulations *sdp_manipulations = sdp_manipulations_get_by_id(flags, media->type_id);
sdp_manipulations_add(s, sdp_manipulations);
}
/* The SDP version gets increased in case:
* - if replace_sdp_version (sdp-version) or replace_origin_full flag is set and SDP information has been updated, or
* - if the force_inc_sdp_ver (force-increment-sdp-ver) flag is set additionally to replace_sdp_version,
* which forces version increase regardless changes in the SDP information.
*/
if (flags->force_inc_sdp_ver || flags->replace_sdp_version || flags->replace_origin_full)
sdp_version_check(s, monologue, !!flags->force_inc_sdp_ver);
out->len = s->len;
out->s = g_string_free(s, FALSE);
return 0;
err:
if (s)
g_string_free(s, TRUE);
ilog(LOG_ERR, "Failed to create SDP: %s", err);
return -1;
}
int sdp_is_duplicate(sdp_sessions_q *sessions) {
for (__auto_type l = sessions->head; l; l = l->next) {
struct sdp_session *s = l->data;
attributes_q *attr_list = attr_list_get_by_id(&s->attributes, ATTR_RTPENGINE);
if (!attr_list)
return 0;
for (__auto_type ql = attr_list->head; ql; ql = ql->next) {
struct sdp_attribute *attr = ql->data;
if (!str_cmp_str(&attr->strs.value, &rtpe_instance_id))
goto next;
}
return 0;
next:
;
}
return 1;
}
void sdp_init(void) {
rand_hex_str(rtpe_instance_id.s, rtpe_instance_id.len / 2);
}