/* $Id$ */ /* * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) * Copyright (C) 2003-2008 Benny Prijono * * 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, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define THIS_FILE "sip_transaction.c" #if 0 #define TSX_TRACE_(expr) PJ_LOG(3,expr) #else #define TSX_TRACE_(expr) #endif /* When this macro is set, transaction will keep the hashed value * so that future lookup (to unregister transaction) does not need * to recalculate the hash again. It should gains a little bit of * performance, so generally we'd want this. */ #define PRECALC_HASH /* Defined in sip_util_statefull.c */ extern pjsip_module mod_stateful_util; /***************************************************************************** ** ** Declarations and static variable definitions section. ** ***************************************************************************** **/ /* Prototypes. */ static pj_status_t mod_tsx_layer_load(pjsip_endpoint *endpt); static pj_status_t mod_tsx_layer_start(void); static pj_status_t mod_tsx_layer_stop(void); static pj_status_t mod_tsx_layer_unload(void); static pj_bool_t mod_tsx_layer_on_rx_request(pjsip_rx_data *rdata); static pj_bool_t mod_tsx_layer_on_rx_response(pjsip_rx_data *rdata); /* Transaction layer module definition. */ static struct mod_tsx_layer { struct pjsip_module mod; pj_pool_t *pool; pjsip_endpoint *endpt; pj_mutex_t *mutex; pj_hash_table_t *htable; } mod_tsx_layer = { { NULL, NULL, /* List's prev and next. */ { "mod-tsx-layer", 13 }, /* Module name. */ -1, /* Module ID */ PJSIP_MOD_PRIORITY_TSX_LAYER, /* Priority. */ mod_tsx_layer_load, /* load(). */ mod_tsx_layer_start, /* start() */ mod_tsx_layer_stop, /* stop() */ mod_tsx_layer_unload, /* unload() */ mod_tsx_layer_on_rx_request, /* on_rx_request() */ mod_tsx_layer_on_rx_response, /* on_rx_response() */ NULL } }; /* Transaction state names */ static const char *state_str[] = { "Null", "Calling", "Trying", "Proceeding", "Completed", "Confirmed", "Terminated", "Destroyed", }; /* Role names */ static const char *role_name[] = { "UAC", "UAS" }; /* Transport flag. */ enum { TSX_HAS_PENDING_TRANSPORT = 1, TSX_HAS_PENDING_RESCHED = 2, TSX_HAS_PENDING_SEND = 4, TSX_HAS_PENDING_DESTROY = 8, TSX_HAS_RESOLVED_SERVER = 16, }; /* Timer timeout value constants */ static pj_time_val t1_timer_val = { PJSIP_T1_TIMEOUT/1000, PJSIP_T1_TIMEOUT%1000 }; static pj_time_val t2_timer_val = { PJSIP_T2_TIMEOUT/1000, PJSIP_T2_TIMEOUT%1000 }; static pj_time_val t4_timer_val = { PJSIP_T4_TIMEOUT/1000, PJSIP_T4_TIMEOUT%1000 }; static pj_time_val td_timer_val = { PJSIP_TD_TIMEOUT/1000, PJSIP_TD_TIMEOUT%1000 }; static pj_time_val timeout_timer_val = { (64*PJSIP_T1_TIMEOUT)/1000, (64*PJSIP_T1_TIMEOUT)%1000 }; #define TIMER_INACTIVE 0 #define RETRANSMIT_TIMER 1 #define TIMEOUT_TIMER 2 #define TRANSPORT_ERR_TIMER 3 /* Flags for tsx_set_state() */ enum { NO_NOTIFY = 1, NO_SCHEDULE_HANDLER = 2, }; /* Prototypes. */ static pj_status_t tsx_on_state_null( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_calling( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_trying( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_proceeding_uas( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_proceeding_uac( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_completed_uas( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_completed_uac( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_confirmed( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_terminated( pjsip_transaction *tsx, pjsip_event *event); static pj_status_t tsx_on_state_destroyed( pjsip_transaction *tsx, pjsip_event *event); static void tsx_timer_callback( pj_timer_heap_t *theap, pj_timer_entry *entry); static void tsx_tp_state_callback( pjsip_transport *tp, pjsip_transport_state state, const pjsip_transport_state_info *info); static void tsx_set_state( pjsip_transaction *tsx, pjsip_tsx_state_e state, pjsip_event_id_e event_src_type, void *event_src, int flag); static void tsx_set_status_code(pjsip_transaction *tsx, int code, const pj_str_t *reason); static pj_status_t tsx_create( pjsip_module *tsx_user, pj_grp_lock_t *grp_lock, pjsip_transaction **p_tsx); static void tsx_on_destroy(void *arg); static pj_status_t tsx_shutdown( pjsip_transaction *tsx ); static void tsx_resched_retransmission( pjsip_transaction *tsx ); static pj_status_t tsx_retransmit( pjsip_transaction *tsx, int resched); static int tsx_send_msg( pjsip_transaction *tsx, pjsip_tx_data *tdata); static void tsx_update_transport( pjsip_transaction *tsx, pjsip_transport *tp); /* State handlers for UAC, indexed by state */ static int (*tsx_state_handler_uac[PJSIP_TSX_STATE_MAX])(pjsip_transaction *, pjsip_event *) = { &tsx_on_state_null, &tsx_on_state_calling, NULL, &tsx_on_state_proceeding_uac, &tsx_on_state_completed_uac, &tsx_on_state_confirmed, &tsx_on_state_terminated, &tsx_on_state_destroyed, }; /* State handlers for UAS */ static int (*tsx_state_handler_uas[PJSIP_TSX_STATE_MAX])(pjsip_transaction *, pjsip_event *) = { &tsx_on_state_null, NULL, &tsx_on_state_trying, &tsx_on_state_proceeding_uas, &tsx_on_state_completed_uas, &tsx_on_state_confirmed, &tsx_on_state_terminated, &tsx_on_state_destroyed, }; /***************************************************************************** ** ** Utilities ** ***************************************************************************** */ /* * Get transaction state name. */ PJ_DEF(const char *) pjsip_tsx_state_str(pjsip_tsx_state_e state) { return state_str[state]; } /* * Get the role name. */ PJ_DEF(const char *) pjsip_role_name(pjsip_role_e role) { return role_name[role]; } /* * Create transaction key for RFC2543 compliant messages, which don't have * unique branch parameter in the top most Via header. * * INVITE requests matches a transaction if the following attributes * match the original request: * - Request-URI * - To tag * - From tag * - Call-ID * - CSeq * - top Via header * * CANCEL matching is done similarly as INVITE, except: * - CSeq method will differ * - To tag is not matched. * * ACK matching is done similarly, except that: * - method of the CSeq will differ, * - To tag is matched to the response sent by the server transaction. * * The transaction key is constructed from the common components of above * components. Additional comparison is needed to fully match a transaction. */ static pj_status_t create_tsx_key_2543( pj_pool_t *pool, pj_str_t *str, pjsip_role_e role, const pjsip_method *method, const pjsip_rx_data *rdata ) { #define SEPARATOR '$' char *key, *p; pj_ssize_t len; pj_size_t len_required; pj_str_t *host; PJ_ASSERT_RETURN(pool && str && method && rdata, PJ_EINVAL); PJ_ASSERT_RETURN(rdata->msg_info.msg, PJ_EINVAL); PJ_ASSERT_RETURN(rdata->msg_info.via, PJSIP_EMISSINGHDR); PJ_ASSERT_RETURN(rdata->msg_info.cseq, PJSIP_EMISSINGHDR); PJ_ASSERT_RETURN(rdata->msg_info.from, PJSIP_EMISSINGHDR); host = &rdata->msg_info.via->sent_by.host; /* Calculate length required. */ len_required = method->name.slen + /* Method */ 11 + /* CSeq number */ rdata->msg_info.from->tag.slen + /* From tag. */ rdata->msg_info.cid->id.slen + /* Call-ID */ host->slen + /* Via host. */ 11 + /* Via port. */ 16; /* Separator+Allowance. */ key = p = (char*) pj_pool_alloc(pool, len_required); /* Add role. */ *p++ = (char)(role==PJSIP_ROLE_UAC ? 'c' : 's'); *p++ = SEPARATOR; /* Add method, except when method is INVITE or ACK. */ if (method->id != PJSIP_INVITE_METHOD && method->id != PJSIP_ACK_METHOD) { pj_memcpy(p, method->name.ptr, method->name.slen); p += method->name.slen; *p++ = '$'; } /* Add CSeq (only the number). */ len = pj_utoa(rdata->msg_info.cseq->cseq, p); p += len; *p++ = SEPARATOR; /* Add From tag. */ len = rdata->msg_info.from->tag.slen; pj_memcpy( p, rdata->msg_info.from->tag.ptr, len); p += len; *p++ = SEPARATOR; /* Add Call-ID. */ len = rdata->msg_info.cid->id.slen; pj_memcpy( p, rdata->msg_info.cid->id.ptr, len ); p += len; *p++ = SEPARATOR; /* Add top Via header. * We don't really care whether the port contains the real port (because * it can be omited if default port is used). Anyway this function is * only used to match request retransmission, and we expect that the * request retransmissions will contain the same port. */ pj_memcpy(p, host->ptr, host->slen); p += host->slen; *p++ = ':'; len = pj_utoa(rdata->msg_info.via->sent_by.port, p); p += len; *p++ = SEPARATOR; *p++ = '\0'; /* Done. */ str->ptr = key; str->slen = p-key; return PJ_SUCCESS; } /* * Create transaction key for RFC3161 compliant system. */ static pj_status_t create_tsx_key_3261( pj_pool_t *pool, pj_str_t *key, pjsip_role_e role, const pjsip_method *method, const pj_str_t *branch) { char *p; PJ_ASSERT_RETURN(pool && key && method && branch, PJ_EINVAL); p = key->ptr = (char*) pj_pool_alloc(pool, branch->slen + method->name.slen + 4 ); /* Add role. */ *p++ = (char)(role==PJSIP_ROLE_UAC ? 'c' : 's'); *p++ = SEPARATOR; /* Add method, except when method is INVITE or ACK. */ if (method->id != PJSIP_INVITE_METHOD && method->id != PJSIP_ACK_METHOD) { pj_memcpy(p, method->name.ptr, method->name.slen); p += method->name.slen; *p++ = '$'; } /* Add branch ID. */ pj_memcpy(p, branch->ptr, branch->slen); p += branch->slen; /* Set length */ key->slen = p - key->ptr; return PJ_SUCCESS; } /* * Create key from the incoming data, to be used to search the transaction * in the transaction hash table. */ PJ_DEF(pj_status_t) pjsip_tsx_create_key( pj_pool_t *pool, pj_str_t *key, pjsip_role_e role, const pjsip_method *method, const pjsip_rx_data *rdata) { pj_str_t rfc3261_branch = {PJSIP_RFC3261_BRANCH_ID, PJSIP_RFC3261_BRANCH_LEN}; /* Get the branch parameter in the top-most Via. * If branch parameter is started with "z9hG4bK", then the message was * generated by agent compliant with RFC3261. Otherwise, it will be * handled as RFC2543. */ const pj_str_t *branch = &rdata->msg_info.via->branch_param; if (pj_strnicmp(branch,&rfc3261_branch,PJSIP_RFC3261_BRANCH_LEN)==0) { /* Create transaction key. */ return create_tsx_key_3261(pool, key, role, method, branch); } else { /* Create the key for the message. This key will be matched up * with the transaction key. For RFC2563 transactions, the * transaction key was created by the same function, so it will * match the message. */ return create_tsx_key_2543( pool, key, role, method, rdata ); } } /***************************************************************************** ** ** Transaction layer module ** ***************************************************************************** **/ /* * Create transaction layer module and registers it to the endpoint. */ PJ_DEF(pj_status_t) pjsip_tsx_layer_init_module(pjsip_endpoint *endpt) { pj_pool_t *pool; pj_status_t status; PJ_ASSERT_RETURN(mod_tsx_layer.endpt==NULL, PJ_EINVALIDOP); /* Initialize timer values */ t1_timer_val.sec = pjsip_cfg()->tsx.t1 / 1000; t1_timer_val.msec = pjsip_cfg()->tsx.t1 % 1000; t2_timer_val.sec = pjsip_cfg()->tsx.t2 / 1000; t2_timer_val.msec = pjsip_cfg()->tsx.t2 % 1000; t4_timer_val.sec = pjsip_cfg()->tsx.t4 / 1000; t4_timer_val.msec = pjsip_cfg()->tsx.t4 % 1000; td_timer_val.sec = pjsip_cfg()->tsx.td / 1000; td_timer_val.msec = pjsip_cfg()->tsx.td % 1000; /* Changed the initialization below to use td_timer_val instead, to enable * customization to the timeout value. */ //timeout_timer_val.sec = (64 * pjsip_cfg()->tsx.t1) / 1000; //timeout_timer_val.msec = (64 * pjsip_cfg()->tsx.t1) % 1000; timeout_timer_val = td_timer_val; /* * Initialize transaction layer structure. */ /* Create pool for the module. */ pool = pjsip_endpt_create_pool(endpt, "tsxlayer", PJSIP_POOL_TSX_LAYER_LEN, PJSIP_POOL_TSX_LAYER_INC ); if (!pool) return PJ_ENOMEM; /* Initialize some attributes. */ mod_tsx_layer.pool = pool; mod_tsx_layer.endpt = endpt; /* Create hash table. */ mod_tsx_layer.htable = pj_hash_create( pool, pjsip_cfg()->tsx.max_count ); if (!mod_tsx_layer.htable) { pjsip_endpt_release_pool(endpt, pool); return PJ_ENOMEM; } /* Create group lock. */ status = pj_mutex_create_recursive(pool, "tsxlayer", &mod_tsx_layer.mutex); if (status != PJ_SUCCESS) { pjsip_endpt_release_pool(endpt, pool); return status; } /* * Register transaction layer module to endpoint. */ status = pjsip_endpt_register_module( endpt, &mod_tsx_layer.mod ); if (status != PJ_SUCCESS) { pj_mutex_destroy(mod_tsx_layer.mutex); pjsip_endpt_release_pool(endpt, pool); return status; } /* Register mod_stateful_util module (sip_util_statefull.c) */ status = pjsip_endpt_register_module(endpt, &mod_stateful_util); if (status != PJ_SUCCESS) { return status; } return PJ_SUCCESS; } /* * Get the instance of transaction layer module. */ PJ_DEF(pjsip_module*) pjsip_tsx_layer_instance(void) { return &mod_tsx_layer.mod; } /* * Unregister and destroy transaction layer module. */ PJ_DEF(pj_status_t) pjsip_tsx_layer_destroy(void) { /* Are we registered? */ PJ_ASSERT_RETURN(mod_tsx_layer.endpt!=NULL, PJ_EINVALIDOP); /* Unregister from endpoint. * Clean-ups will be done in the unload() module callback. */ return pjsip_endpt_unregister_module( mod_tsx_layer.endpt, &mod_tsx_layer.mod); } /* * Register the transaction to the hash table. */ static pj_status_t mod_tsx_layer_register_tsx( pjsip_transaction *tsx) { pj_assert(tsx->transaction_key.slen != 0); /* Lock hash table mutex. */ pj_mutex_lock(mod_tsx_layer.mutex); /* Check if no transaction with the same key exists. * Do not use PJ_ASSERT_RETURN since it evaluates the expression * twice! */ if(pj_hash_get_lower(mod_tsx_layer.htable, tsx->transaction_key.ptr, (unsigned)tsx->transaction_key.slen, NULL)) { pj_mutex_unlock(mod_tsx_layer.mutex); PJ_LOG(2,(THIS_FILE, "Unable to register %.*s transaction (key exists)", (int)tsx->method.name.slen, tsx->method.name.ptr)); return PJ_EEXISTS; } TSX_TRACE_((THIS_FILE, "Transaction %p registered with hkey=0x%p and key=%.*s", tsx, tsx->hashed_key, tsx->transaction_key.slen, tsx->transaction_key.ptr)); /* Register the transaction to the hash table. */ #ifdef PRECALC_HASH pj_hash_set_lower( tsx->pool, mod_tsx_layer.htable, tsx->transaction_key.ptr, (unsigned)tsx->transaction_key.slen, tsx->hashed_key, tsx); #else pj_hash_set_lower( tsx->pool, mod_tsx_layer.htable, tsx->transaction_key.ptr, tsx->transaction_key.slen, 0, tsx); #endif /* Unlock mutex. */ pj_mutex_unlock(mod_tsx_layer.mutex); return PJ_SUCCESS; } /* * Unregister the transaction from the hash table. */ static void mod_tsx_layer_unregister_tsx( pjsip_transaction *tsx) { if (mod_tsx_layer.mod.id == -1) { /* The transaction layer has been unregistered. This could happen * if the transaction was pending on transport and the application * is shutdown. See http://trac.pjsip.org/repos/ticket/1033. In * this case just do nothing. */ return; } pj_assert(tsx->transaction_key.slen != 0); //pj_assert(tsx->state != PJSIP_TSX_STATE_NULL); /* Lock hash table mutex. */ pj_mutex_lock(mod_tsx_layer.mutex); /* Register the transaction to the hash table. */ #ifdef PRECALC_HASH pj_hash_set_lower( NULL, mod_tsx_layer.htable, tsx->transaction_key.ptr, (unsigned)tsx->transaction_key.slen, tsx->hashed_key, NULL); #else pj_hash_set_lower( NULL, mod_tsx_layer.htable, tsx->transaction_key.ptr, tsx->transaction_key.slen, 0, NULL); #endif TSX_TRACE_((THIS_FILE, "Transaction %p unregistered, hkey=0x%p and key=%.*s", tsx, tsx->hashed_key, tsx->transaction_key.slen, tsx->transaction_key.ptr)); /* Unlock mutex. */ pj_mutex_unlock(mod_tsx_layer.mutex); } /* * Retrieve the current number of transactions currently registered in * the hash table. */ PJ_DEF(unsigned) pjsip_tsx_layer_get_tsx_count(void) { unsigned count; /* Are we registered? */ PJ_ASSERT_RETURN(mod_tsx_layer.endpt!=NULL, 0); pj_mutex_lock(mod_tsx_layer.mutex); count = pj_hash_count(mod_tsx_layer.htable); pj_mutex_unlock(mod_tsx_layer.mutex); return count; } /* * Find a transaction. */ static pjsip_transaction* find_tsx( const pj_str_t *key, pj_bool_t lock, pj_bool_t add_ref ) { pjsip_transaction *tsx; pj_uint32_t hval = 0; pj_mutex_lock(mod_tsx_layer.mutex); tsx = (pjsip_transaction*) pj_hash_get_lower( mod_tsx_layer.htable, key->ptr, (unsigned)key->slen, &hval ); /* Prevent the transaction to get deleted before we have chance to lock it. */ if (tsx) pj_grp_lock_add_ref(tsx->grp_lock); pj_mutex_unlock(mod_tsx_layer.mutex); TSX_TRACE_((THIS_FILE, "Finding tsx with hkey=0x%p and key=%.*s: found %p", hval, key->slen, key->ptr, tsx)); /* Simulate race condition! */ PJ_RACE_ME(5); if (tsx) { if (lock) pj_grp_lock_acquire(tsx->grp_lock); if (!add_ref) pj_grp_lock_dec_ref(tsx->grp_lock); } return tsx; } PJ_DEF(pjsip_transaction*) pjsip_tsx_layer_find_tsx( const pj_str_t *key, pj_bool_t lock ) { return find_tsx(key, lock, PJ_FALSE); } PJ_DEF(pjsip_transaction*) pjsip_tsx_layer_find_tsx2( const pj_str_t *key, pj_bool_t add_ref ) { return find_tsx(key, PJ_FALSE, add_ref); } /* This module callback is called when module is being loaded by * endpoint. It does nothing for this module. */ static pj_status_t mod_tsx_layer_load(pjsip_endpoint *endpt) { PJ_UNUSED_ARG(endpt); return PJ_SUCCESS; } /* This module callback is called when module is being started by * endpoint. It does nothing for this module. */ static pj_status_t mod_tsx_layer_start(void) { return PJ_SUCCESS; } /* This module callback is called when module is being stopped by * endpoint. */ static pj_status_t mod_tsx_layer_stop(void) { pj_hash_iterator_t it_buf, *it; PJ_LOG(4,(THIS_FILE, "Stopping transaction layer module")); pj_mutex_lock(mod_tsx_layer.mutex); /* Destroy all transactions. */ it = pj_hash_first(mod_tsx_layer.htable, &it_buf); while (it) { pjsip_transaction *tsx = (pjsip_transaction*) pj_hash_this(mod_tsx_layer.htable, it); pj_hash_iterator_t *next = pj_hash_next(mod_tsx_layer.htable, it); if (tsx) { pjsip_tsx_terminate(tsx, PJSIP_SC_SERVICE_UNAVAILABLE); mod_tsx_layer_unregister_tsx(tsx); tsx_shutdown(tsx); } it = next; } pj_mutex_unlock(mod_tsx_layer.mutex); PJ_LOG(4,(THIS_FILE, "Stopped transaction layer module")); return PJ_SUCCESS; } /* Destroy this module */ static void tsx_layer_destroy(pjsip_endpoint *endpt) { PJ_UNUSED_ARG(endpt); /* Destroy mutex. */ pj_mutex_destroy(mod_tsx_layer.mutex); /* Release pool. */ pjsip_endpt_release_pool(mod_tsx_layer.endpt, mod_tsx_layer.pool); /* Mark as unregistered. */ mod_tsx_layer.endpt = NULL; PJ_LOG(4,(THIS_FILE, "Transaction layer module destroyed")); } /* This module callback is called when module is being unloaded by * endpoint. */ static pj_status_t mod_tsx_layer_unload(void) { /* Only self destroy when there's no transaction in the table. * Transaction may refuse to destroy when it has pending * transmission. If we destroy the module now, application will * crash when the pending transaction finally got error response * from transport and when it tries to unregister itself. */ if (pj_hash_count(mod_tsx_layer.htable) != 0) { pj_status_t status; status = pjsip_endpt_atexit(mod_tsx_layer.endpt, &tsx_layer_destroy); if (status != PJ_SUCCESS) { PJ_PERROR(3,(THIS_FILE, status, "Failed to register transaction layer module destroy.")); } return PJ_EBUSY; } tsx_layer_destroy(mod_tsx_layer.endpt); return PJ_SUCCESS; } /* This module callback is called when endpoint has received an * incoming request message. */ static pj_bool_t mod_tsx_layer_on_rx_request(pjsip_rx_data *rdata) { pj_str_t key; pj_uint32_t hval = 0; pjsip_transaction *tsx; pjsip_tsx_create_key(rdata->tp_info.pool, &key, PJSIP_ROLE_UAS, &rdata->msg_info.cseq->method, rdata); /* Find transaction. */ pj_mutex_lock( mod_tsx_layer.mutex ); tsx = (pjsip_transaction*) pj_hash_get_lower( mod_tsx_layer.htable, key.ptr, (unsigned)key.slen, &hval ); TSX_TRACE_((THIS_FILE, "Finding tsx for request, hkey=0x%p and key=%.*s, found %p", hval, key.slen, key.ptr, tsx)); if (tsx == NULL || tsx->state == PJSIP_TSX_STATE_TERMINATED) { /* Transaction not found. * Reject the request so that endpoint passes the request to * upper layer modules. */ pj_mutex_unlock( mod_tsx_layer.mutex); return PJ_FALSE; } /* Prevent the transaction to get deleted before we have chance to lock it * in pjsip_tsx_recv_msg(). */ pj_grp_lock_add_ref(tsx->grp_lock); /* Unlock hash table. */ pj_mutex_unlock( mod_tsx_layer.mutex ); /* Simulate race condition! */ PJ_RACE_ME(5); /* Pass the message to the transaction. */ pjsip_tsx_recv_msg(tsx, rdata ); pj_grp_lock_dec_ref(tsx->grp_lock); return PJ_TRUE; } /* This module callback is called when endpoint has received an * incoming response message. */ static pj_bool_t mod_tsx_layer_on_rx_response(pjsip_rx_data *rdata) { pj_str_t key; pj_uint32_t hval = 0; pjsip_transaction *tsx; pjsip_tsx_create_key(rdata->tp_info.pool, &key, PJSIP_ROLE_UAC, &rdata->msg_info.cseq->method, rdata); /* Find transaction. */ pj_mutex_lock( mod_tsx_layer.mutex ); tsx = (pjsip_transaction*) pj_hash_get_lower( mod_tsx_layer.htable, key.ptr, (unsigned)key.slen, &hval ); TSX_TRACE_((THIS_FILE, "Finding tsx for response, hkey=0x%p and key=%.*s, found %p", hval, key.slen, key.ptr, tsx)); if (tsx == NULL || tsx->state == PJSIP_TSX_STATE_TERMINATED) { /* Transaction not found. * Reject the request so that endpoint passes the request to * upper layer modules. */ pj_mutex_unlock( mod_tsx_layer.mutex); return PJ_FALSE; } /* Prevent the transaction to get deleted before we have chance to lock it * in pjsip_tsx_recv_msg(). */ pj_grp_lock_add_ref(tsx->grp_lock); /* Unlock hash table. */ pj_mutex_unlock( mod_tsx_layer.mutex ); /* Simulate race condition! */ PJ_RACE_ME(5); /* Pass the message to the transaction. */ pjsip_tsx_recv_msg(tsx, rdata ); pj_grp_lock_dec_ref(tsx->grp_lock); return PJ_TRUE; } /* * Get transaction instance in the rdata. */ PJ_DEF(pjsip_transaction*) pjsip_rdata_get_tsx( pjsip_rx_data *rdata ) { return (pjsip_transaction*) rdata->endpt_info.mod_data[mod_tsx_layer.mod.id]; } /* * Dump transaction layer. */ PJ_DEF(void) pjsip_tsx_layer_dump(pj_bool_t detail) { #if PJ_LOG_MAX_LEVEL >= 3 pj_hash_iterator_t itbuf, *it; /* Lock mutex. */ pj_mutex_lock(mod_tsx_layer.mutex); PJ_LOG(3, (THIS_FILE, "Dumping transaction table:")); PJ_LOG(3, (THIS_FILE, " Total %d transactions", pj_hash_count(mod_tsx_layer.htable))); if (detail) { it = pj_hash_first(mod_tsx_layer.htable, &itbuf); if (it == NULL) { PJ_LOG(3, (THIS_FILE, " - none - ")); } else { while (it != NULL) { pjsip_transaction *tsx = (pjsip_transaction*) pj_hash_this(mod_tsx_layer.htable,it); PJ_LOG(3, (THIS_FILE, " %s %s|%d|%s", tsx->obj_name, (tsx->last_tx? pjsip_tx_data_get_info(tsx->last_tx): "none"), tsx->status_code, pjsip_tsx_state_str(tsx->state))); it = pj_hash_next(mod_tsx_layer.htable, it); } } } /* Unlock mutex. */ pj_mutex_unlock(mod_tsx_layer.mutex); #endif } /***************************************************************************** ** ** Transaction ** ***************************************************************************** **/ /* Lock transaction for accessing the timeout timer only. */ static void lock_timer(pjsip_transaction *tsx) { pj_mutex_lock(tsx->mutex_b); } /* Unlock timer */ static void unlock_timer(pjsip_transaction *tsx) { pj_mutex_unlock(tsx->mutex_b); } /* Utility: schedule a timer */ static pj_status_t tsx_schedule_timer(pjsip_transaction *tsx, pj_timer_entry *entry, const pj_time_val *delay, int active_id) { pj_timer_heap_t *timer_heap = pjsip_endpt_get_timer_heap(tsx->endpt); pj_status_t status; pj_assert(active_id != 0); status = pj_timer_heap_schedule_w_grp_lock(timer_heap, entry, delay, active_id, tsx->grp_lock); return status; } /* Utility: cancel a timer */ static int tsx_cancel_timer(pjsip_transaction *tsx, pj_timer_entry *entry) { pj_timer_heap_t *timer_heap = pjsip_endpt_get_timer_heap(tsx->endpt); return pj_timer_heap_cancel_if_active(timer_heap, entry, TIMER_INACTIVE); } /* Create and initialize basic transaction structure. * This function is called by both UAC and UAS creation. */ static pj_status_t tsx_create( pjsip_module *tsx_user, pj_grp_lock_t *grp_lock, pjsip_transaction **p_tsx) { pj_pool_t *pool; pjsip_transaction *tsx; pj_status_t status; pool = pjsip_endpt_create_pool( mod_tsx_layer.endpt, "tsx", PJSIP_POOL_TSX_LEN, PJSIP_POOL_TSX_INC ); if (!pool) return PJ_ENOMEM; tsx = PJ_POOL_ZALLOC_T(pool, pjsip_transaction); tsx->pool = pool; tsx->tsx_user = tsx_user; tsx->endpt = mod_tsx_layer.endpt; pj_ansi_snprintf(tsx->obj_name, sizeof(tsx->obj_name), "tsx%p", tsx); pj_memcpy(pool->obj_name, tsx->obj_name, sizeof(pool->obj_name)); tsx->handle_200resp = 1; tsx->retransmit_timer.id = TIMER_INACTIVE; tsx->retransmit_timer.user_data = tsx; tsx->retransmit_timer.cb = &tsx_timer_callback; tsx->timeout_timer.id = TIMER_INACTIVE; tsx->timeout_timer.user_data = tsx; tsx->timeout_timer.cb = &tsx_timer_callback; if (grp_lock) { tsx->grp_lock = grp_lock; pj_grp_lock_add_ref(tsx->grp_lock); pj_grp_lock_add_handler(tsx->grp_lock, tsx->pool, tsx, &tsx_on_destroy); } else { status = pj_grp_lock_create_w_handler(pool, NULL, tsx, &tsx_on_destroy, &tsx->grp_lock); if (status != PJ_SUCCESS) { pjsip_endpt_release_pool(mod_tsx_layer.endpt, pool); return status; } pj_grp_lock_add_ref(tsx->grp_lock); } status = pj_mutex_create_simple(pool, tsx->obj_name, &tsx->mutex_b); if (status != PJ_SUCCESS) { tsx_shutdown(tsx); return status; } *p_tsx = tsx; return PJ_SUCCESS; } /* Really destroy transaction, when grp_lock reference is zero */ static void tsx_on_destroy( void *arg ) { pjsip_transaction *tsx = (pjsip_transaction*)arg; PJ_LOG(5,(tsx->obj_name, "Transaction destroyed!")); pj_mutex_destroy(tsx->mutex_b); pjsip_endpt_release_pool(tsx->endpt, tsx->pool); } /* Shutdown transaction. */ static pj_status_t tsx_shutdown( pjsip_transaction *tsx ) { /* Release the transport */ tsx_update_transport(tsx, NULL); /* Decrement reference counter in transport selector, only if * we haven't been called before */ if (!tsx->terminating) { pjsip_tpselector_dec_ref(&tsx->tp_sel); } /* Free last transmitted message. */ if (tsx->last_tx) { pjsip_tx_data_dec_ref( tsx->last_tx ); tsx->last_tx = NULL; } /* Cancel timeout timer. */ tsx_cancel_timer(tsx, &tsx->timeout_timer); /* Cancel retransmission timer. */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); /* Clear some pending flags. */ tsx->transport_flag &= ~(TSX_HAS_PENDING_RESCHED | TSX_HAS_PENDING_SEND); /* Refuse to destroy transaction if it has pending resolving. */ if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { tsx->transport_flag |= TSX_HAS_PENDING_DESTROY; tsx->tsx_user = NULL; PJ_LOG(4,(tsx->obj_name, "Will destroy later because transport is " "in progress")); } if (!tsx->terminating) { tsx->terminating = PJ_TRUE; pj_grp_lock_dec_ref(tsx->grp_lock); } /* No acccess to tsx after this, it may have been destroyed */ return PJ_SUCCESS; } /* * Callback when timer expires. Transport error also piggybacks this event * to avoid deadlock (https://trac.pjsip.org/repos/ticket/1646). */ static void tsx_timer_callback( pj_timer_heap_t *theap, pj_timer_entry *entry) { pjsip_transaction *tsx = (pjsip_transaction*) entry->user_data; PJ_UNUSED_ARG(theap); /* Just return if transaction is already destroyed (see also #2102). */ if (tsx->state >= PJSIP_TSX_STATE_DESTROYED) { return; } if (entry->id == TRANSPORT_ERR_TIMER) { /* Posted transport error event */ entry->id = 0; if (tsx->state < PJSIP_TSX_STATE_TERMINATED) { pjsip_tsx_state_e prev_state; pj_time_val timeout = { 0, 0 }; pj_grp_lock_acquire(tsx->grp_lock); prev_state = tsx->state; /* Release transport as it's no longer working. */ tsx_update_transport(tsx, NULL); if (tsx->status_code < 200) { pj_str_t err; char errmsg[PJ_ERR_MSG_SIZE]; err = pj_strerror(tsx->transport_err, errmsg, sizeof(errmsg)); tsx_set_status_code(tsx, PJSIP_SC_TSX_TRANSPORT_ERROR, &err); } /* Set transaction state etc, but don't notify TU now, * otherwise we'll get a deadlock. See: * https://trac.pjsip.org/repos/ticket/1646 */ /* Also don't schedule tsx handler, otherwise we'll get race * condition of TU notifications due to delayed TERMINATED * state TU notification. It happened in multiple worker threads * environment between TERMINATED & DESTROYED! See: * https://trac.pjsip.org/repos/ticket/1902 */ tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TRANSPORT_ERROR, NULL, NO_NOTIFY | NO_SCHEDULE_HANDLER); pj_grp_lock_release(tsx->grp_lock); /* Now notify TU about state change, WITHOUT holding the * group lock. It should be safe to do so; transaction will * not get destroyed because group lock reference counter * has been incremented by the timer heap. */ if (tsx->tsx_user && tsx->tsx_user->on_tsx_state) { pjsip_event e; PJSIP_EVENT_INIT_TSX_STATE(e, tsx, PJSIP_EVENT_TRANSPORT_ERROR, NULL, prev_state); (*tsx->tsx_user->on_tsx_state)(tsx, &e); } /* Now let's schedule the tsx handler */ tsx_schedule_timer(tsx, &tsx->timeout_timer, &timeout, TIMEOUT_TIMER); } } else { pjsip_event event; entry->id = 0; PJ_LOG(5,(tsx->obj_name, "%s timer event", (entry==&tsx->retransmit_timer ? "Retransmit":"Timeout"))); pj_log_push_indent(); PJSIP_EVENT_INIT_TIMER(event, entry); /* Dispatch event to transaction. */ pj_grp_lock_acquire(tsx->grp_lock); (*tsx->state_handler)(tsx, &event); pj_grp_lock_release(tsx->grp_lock); pj_log_pop_indent(); } } /* * Set transaction state, and inform TU about the transaction state change. */ static void tsx_set_state( pjsip_transaction *tsx, pjsip_tsx_state_e state, pjsip_event_id_e event_src_type, void *event_src, int flag) { pjsip_tsx_state_e prev_state = tsx->state; /* New state must be greater than previous state */ pj_assert(state >= tsx->state); PJ_LOG(5, (tsx->obj_name, "State changed from %s to %s, event=%s", state_str[tsx->state], state_str[state], pjsip_event_str(event_src_type))); pj_log_push_indent(); /* Change state. */ tsx->state = state; /* Update the state handlers. */ if (tsx->role == PJSIP_ROLE_UAC) { tsx->state_handler = tsx_state_handler_uac[state]; } else { tsx->state_handler = tsx_state_handler_uas[state]; } /* Before informing TU about state changed, inform TU about * rx event. */ if (event_src_type==PJSIP_EVENT_RX_MSG && tsx->tsx_user && (flag & NO_NOTIFY)==0) { pjsip_rx_data *rdata = (pjsip_rx_data*) event_src; pj_assert(rdata != NULL); if (rdata->msg_info.msg->type == PJSIP_RESPONSE_MSG && tsx->tsx_user->on_rx_response) { (*tsx->tsx_user->on_rx_response)(rdata); } } /* Inform TU about state changed. */ if (tsx->tsx_user && tsx->tsx_user->on_tsx_state && (flag & NO_NOTIFY) == 0) { pjsip_event e; PJSIP_EVENT_INIT_TSX_STATE(e, tsx, event_src_type, event_src, prev_state); /* For timer event, release lock to avoid deadlock. * This should be safe because: * 1. The tsx state just switches to TERMINATED or DESTROYED. * 2. There should be no other processing taking place. All other * events, such as the ones handled by tsx_on_state_terminated() * should be ignored. * 3. tsx_shutdown() hasn't been called. * Refer to ticket #2001 (https://trac.pjsip.org/repos/ticket/2001). */ if (event_src_type == PJSIP_EVENT_TIMER && (pj_timer_entry *)event_src == &tsx->timeout_timer) { pj_grp_lock_release(tsx->grp_lock); } (*tsx->tsx_user->on_tsx_state)(tsx, &e); if (event_src_type == PJSIP_EVENT_TIMER && (pj_timer_entry *)event_src == &tsx->timeout_timer) { pj_grp_lock_acquire(tsx->grp_lock); } } /* When the transaction is terminated, release transport, and free the * saved last transmitted message. */ if (state == PJSIP_TSX_STATE_TERMINATED) { pj_time_val timeout = { 0, 0 }; /* If we're still waiting for a message to be sent.. */ if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { /* Disassociate ourselves from the outstanding transmit data * so that when the send callback is called we will be able * to ignore that (otherwise we'll get assertion, see * http://trac.pjsip.org/repos/ticket/1033) */ if (tsx->pending_tx) { tsx->pending_tx->mod_data[mod_tsx_layer.mod.id] = NULL; tsx->pending_tx = NULL; } tsx->transport_flag &= ~(TSX_HAS_PENDING_TRANSPORT); } lock_timer(tsx); tsx_cancel_timer(tsx, &tsx->timeout_timer); if ((flag & NO_SCHEDULE_HANDLER) == 0) { tsx_schedule_timer(tsx, &tsx->timeout_timer, &timeout, TIMEOUT_TIMER); } unlock_timer(tsx); } else if (state == PJSIP_TSX_STATE_DESTROYED) { /* Unregister transaction. */ mod_tsx_layer_unregister_tsx(tsx); /* Destroy transaction. */ tsx_shutdown(tsx); } pj_log_pop_indent(); } /* * Create, initialize, and register UAC transaction. */ PJ_DEF(pj_status_t) pjsip_tsx_create_uac( pjsip_module *tsx_user, pjsip_tx_data *tdata, pjsip_transaction **p_tsx) { return pjsip_tsx_create_uac2(tsx_user, tdata, NULL, p_tsx); } PJ_DEF(pj_status_t) pjsip_tsx_create_uac2(pjsip_module *tsx_user, pjsip_tx_data *tdata, pj_grp_lock_t *grp_lock, pjsip_transaction **p_tsx) { pjsip_transaction *tsx; pjsip_msg *msg; pjsip_cseq_hdr *cseq; pjsip_via_hdr *via; pjsip_host_info dst_info; pj_status_t status; /* Validate arguments. */ PJ_ASSERT_RETURN(tdata && tdata->msg && p_tsx, PJ_EINVAL); PJ_ASSERT_RETURN(tdata->msg->type == PJSIP_REQUEST_MSG, PJSIP_ENOTREQUESTMSG); /* Method MUST NOT be ACK! */ PJ_ASSERT_RETURN(tdata->msg->line.req.method.id != PJSIP_ACK_METHOD, PJ_EINVALIDOP); /* Keep shortcut */ msg = tdata->msg; /* Make sure CSeq header is present. */ cseq = (pjsip_cseq_hdr*) pjsip_msg_find_hdr(msg, PJSIP_H_CSEQ, NULL); if (!cseq) { pj_assert(!"CSeq header not present in outgoing message!"); return PJSIP_EMISSINGHDR; } /* Create transaction instance. */ status = tsx_create( tsx_user, grp_lock, &tsx); if (status != PJ_SUCCESS) return status; /* Lock transaction. * We don't need to lock the group lock if none was supplied, while the * newly created group lock has not been exposed. */ if (grp_lock) pj_grp_lock_acquire(tsx->grp_lock); /* Role is UAC. */ tsx->role = PJSIP_ROLE_UAC; /* Save method. */ pjsip_method_copy( tsx->pool, &tsx->method, &msg->line.req.method); /* Save CSeq. */ tsx->cseq = cseq->cseq; /* Generate Via header if it doesn't exist. */ via = (pjsip_via_hdr*) pjsip_msg_find_hdr(msg, PJSIP_H_VIA, NULL); if (via == NULL) { via = pjsip_via_hdr_create(tdata->pool); pjsip_msg_insert_first_hdr(msg, (pjsip_hdr*) via); } /* Generate branch parameter if it doesn't exist. */ if (via->branch_param.slen == 0) { pj_str_t tmp; via->branch_param.ptr = (char*) pj_pool_alloc(tsx->pool, PJSIP_MAX_BRANCH_LEN); via->branch_param.slen = PJSIP_MAX_BRANCH_LEN; pj_memcpy(via->branch_param.ptr, PJSIP_RFC3261_BRANCH_ID, PJSIP_RFC3261_BRANCH_LEN); tmp.ptr = via->branch_param.ptr + PJSIP_RFC3261_BRANCH_LEN + 2; *(tmp.ptr-2) = 80; *(tmp.ptr-1) = 106; pj_generate_unique_string( &tmp ); /* Save branch parameter. */ tsx->branch = via->branch_param; } else { /* Copy branch parameter. */ pj_strdup(tsx->pool, &tsx->branch, &via->branch_param); } /* Generate transaction key. */ create_tsx_key_3261( tsx->pool, &tsx->transaction_key, PJSIP_ROLE_UAC, &tsx->method, &via->branch_param); /* Calculate hashed key value. */ #ifdef PRECALC_HASH tsx->hashed_key = pj_hash_calc_tolower(0, NULL, &tsx->transaction_key); #endif PJ_LOG(6, (tsx->obj_name, "tsx_key=%.*s", tsx->transaction_key.slen, tsx->transaction_key.ptr)); /* Begin with State_Null. * Manually set-up the state becase we don't want to call the callback. */ tsx->state = PJSIP_TSX_STATE_NULL; tsx->state_handler = &tsx_on_state_null; /* Save the message. */ tsx->last_tx = tdata; pjsip_tx_data_add_ref(tsx->last_tx); /* Determine whether reliable transport should be used initially. * This will be updated whenever transport has changed. */ status = pjsip_get_request_dest(tdata, &dst_info); if (status != PJ_SUCCESS) { if (grp_lock) pj_grp_lock_release(tsx->grp_lock); tsx_shutdown(tsx); return status; } tsx->is_reliable = (dst_info.flag & PJSIP_TRANSPORT_RELIABLE); /* Register transaction to hash table. */ status = mod_tsx_layer_register_tsx(tsx); if (status != PJ_SUCCESS) { /* The assertion is removed by #1090: pj_assert(!"Bug in branch_param generator (i.e. not unique)"); */ if (grp_lock) pj_grp_lock_release(tsx->grp_lock); tsx_shutdown(tsx); return status; } /* Unlock transaction and return. */ if (grp_lock) pj_grp_lock_release(tsx->grp_lock); pj_log_push_indent(); PJ_LOG(5,(tsx->obj_name, "Transaction created for %s", pjsip_tx_data_get_info(tdata))); pj_log_pop_indent(); *p_tsx = tsx; return PJ_SUCCESS; } /* * Create, initialize, and register UAS transaction. */ PJ_DEF(pj_status_t) pjsip_tsx_create_uas( pjsip_module *tsx_user, pjsip_rx_data *rdata, pjsip_transaction **p_tsx) { return pjsip_tsx_create_uas2(tsx_user, rdata, NULL, p_tsx); } PJ_DEF(pj_status_t) pjsip_tsx_create_uas2(pjsip_module *tsx_user, pjsip_rx_data *rdata, pj_grp_lock_t *grp_lock, pjsip_transaction **p_tsx) { pjsip_transaction *tsx; pjsip_msg *msg; pj_str_t *branch; pjsip_cseq_hdr *cseq; pj_status_t status; /* Validate arguments. */ PJ_ASSERT_RETURN(rdata && rdata->msg_info.msg && p_tsx, PJ_EINVAL); /* Keep shortcut to message */ msg = rdata->msg_info.msg; /* Make sure this is a request message. */ PJ_ASSERT_RETURN(msg->type == PJSIP_REQUEST_MSG, PJSIP_ENOTREQUESTMSG); /* Make sure method is not ACK */ PJ_ASSERT_RETURN(msg->line.req.method.id != PJSIP_ACK_METHOD, PJ_EINVALIDOP); /* Make sure CSeq header is present. */ cseq = rdata->msg_info.cseq; if (!cseq) return PJSIP_EMISSINGHDR; /* Make sure Via header is present. */ if (rdata->msg_info.via == NULL) return PJSIP_EMISSINGHDR; /* Check that method in CSeq header match request method. * Reference: PROTOS #1922 */ if (pjsip_method_cmp(&msg->line.req.method, &rdata->msg_info.cseq->method) != 0) { PJ_LOG(4,(THIS_FILE, "Error: CSeq header contains different " "method than the request line")); return PJSIP_EINVALIDHDR; } /* * Create transaction instance. */ status = tsx_create( tsx_user, grp_lock, &tsx); if (status != PJ_SUCCESS) return status; /* Lock transaction. */ pj_grp_lock_acquire(tsx->grp_lock); /* Role is UAS */ tsx->role = PJSIP_ROLE_UAS; /* Save method. */ pjsip_method_copy( tsx->pool, &tsx->method, &msg->line.req.method); /* Save CSeq */ tsx->cseq = cseq->cseq; /* Get transaction key either from branch for RFC3261 message, or * create transaction key. */ status = pjsip_tsx_create_key(tsx->pool, &tsx->transaction_key, PJSIP_ROLE_UAS, &tsx->method, rdata); if (status != PJ_SUCCESS) { pj_grp_lock_release(tsx->grp_lock); tsx_shutdown(tsx); return status; } /* Calculate hashed key value. */ #ifdef PRECALC_HASH tsx->hashed_key = pj_hash_calc_tolower(0, NULL, &tsx->transaction_key); #endif /* Duplicate branch parameter for transaction. */ branch = &rdata->msg_info.via->branch_param; pj_strdup(tsx->pool, &tsx->branch, branch); PJ_LOG(6, (tsx->obj_name, "tsx_key=%.*s", tsx->transaction_key.slen, tsx->transaction_key.ptr)); /* Begin with state NULL. * Manually set-up the state becase we don't want to call the callback. */ tsx->state = PJSIP_TSX_STATE_NULL; tsx->state_handler = &tsx_on_state_null; /* Get response address. */ status = pjsip_get_response_addr( tsx->pool, rdata, &tsx->res_addr ); if (status != PJ_SUCCESS) { pj_grp_lock_release(tsx->grp_lock); tsx_shutdown(tsx); return status; } /* If it's decided that we should use current transport, keep the * transport. */ if (tsx->res_addr.transport) { tsx_update_transport(tsx, tsx->res_addr.transport); pj_memcpy(&tsx->addr, &tsx->res_addr.addr, tsx->res_addr.addr_len); tsx->addr_len = tsx->res_addr.addr_len; tsx->is_reliable = PJSIP_TRANSPORT_IS_RELIABLE(tsx->transport); } else { tsx->is_reliable = (tsx->res_addr.dst_host.flag & PJSIP_TRANSPORT_RELIABLE); } /* Register the transaction. */ status = mod_tsx_layer_register_tsx(tsx); if (status != PJ_SUCCESS) { pj_grp_lock_release(tsx->grp_lock); tsx_shutdown(tsx); return status; } /* Put this transaction in rdata's mod_data. */ rdata->endpt_info.mod_data[mod_tsx_layer.mod.id] = tsx; /* Unlock transaction and return. */ pj_grp_lock_release(tsx->grp_lock); pj_log_push_indent(); PJ_LOG(5,(tsx->obj_name, "Transaction created for %s", pjsip_rx_data_get_info(rdata))); pj_log_pop_indent(); *p_tsx = tsx; return PJ_SUCCESS; } /* * Bind transaction to a specific transport/listener. */ PJ_DEF(pj_status_t) pjsip_tsx_set_transport(pjsip_transaction *tsx, const pjsip_tpselector *sel) { /* Must be UAC transaction */ PJ_ASSERT_RETURN(tsx && sel, PJ_EINVAL); /* Start locking the transaction. */ pj_grp_lock_acquire(tsx->grp_lock); /* Decrement reference counter of previous transport selector */ pjsip_tpselector_dec_ref(&tsx->tp_sel); /* Copy transport selector structure .*/ pj_memcpy(&tsx->tp_sel, sel, sizeof(*sel)); /* Increment reference counter */ pjsip_tpselector_add_ref(&tsx->tp_sel); /* Unlock transaction. */ pj_grp_lock_release(tsx->grp_lock); return PJ_SUCCESS; } /* * Set transaction status code and reason. */ static void tsx_set_status_code(pjsip_transaction *tsx, int code, const pj_str_t *reason) { tsx->status_code = code; if (reason) pj_strdup(tsx->pool, &tsx->status_text, reason); else tsx->status_text = *pjsip_get_status_text(code); } /* * Forcely terminate transaction. */ PJ_DEF(pj_status_t) pjsip_tsx_terminate( pjsip_transaction *tsx, int code ) { PJ_ASSERT_RETURN(tsx != NULL, PJ_EINVAL); PJ_LOG(5,(tsx->obj_name, "Request to terminate transaction")); PJ_ASSERT_RETURN(code >= 200, PJ_EINVAL); pj_log_push_indent(); pj_grp_lock_acquire(tsx->grp_lock); if (tsx->state < PJSIP_TSX_STATE_TERMINATED) { tsx_set_status_code(tsx, code, NULL); tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_USER, NULL, 0); } pj_grp_lock_release(tsx->grp_lock); pj_log_pop_indent(); return PJ_SUCCESS; } /* * Cease retransmission on the UAC transaction. The UAC transaction is * still considered running, and it will complete when either final * response is received or the transaction times out. */ PJ_DEF(pj_status_t) pjsip_tsx_stop_retransmit(pjsip_transaction *tsx) { PJ_ASSERT_RETURN(tsx != NULL, PJ_EINVAL); PJ_ASSERT_RETURN(tsx->role == PJSIP_ROLE_UAC && tsx->method.id == PJSIP_INVITE_METHOD, PJ_EINVALIDOP); PJ_LOG(5,(tsx->obj_name, "Request to stop retransmission")); pj_log_push_indent(); pj_grp_lock_acquire(tsx->grp_lock); /* Cancel retransmission timer. */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); pj_grp_lock_release(tsx->grp_lock); pj_log_pop_indent(); return PJ_SUCCESS; } /* * Start a timer to terminate transaction after the specified time * has elapsed. */ PJ_DEF(pj_status_t) pjsip_tsx_set_timeout( pjsip_transaction *tsx, unsigned millisec) { pj_time_val timeout; PJ_ASSERT_RETURN(tsx != NULL, PJ_EINVAL); PJ_ASSERT_RETURN(tsx->role == PJSIP_ROLE_UAC && tsx->method.id == PJSIP_INVITE_METHOD, PJ_EINVALIDOP); /* Note: must not call pj_grp_lock_acquire(tsx->grp_lock) as * that would introduce deadlock. See #1121. */ lock_timer(tsx); /* Transaction should normally not have final response, but as * #1121 says there is a (tolerable) window of race condition * where this might happen. */ if (tsx->status_code >= 200 && tsx->timeout_timer.id != 0) { /* Timeout is already set */ unlock_timer(tsx); return PJ_EEXISTS; } tsx_cancel_timer(tsx, &tsx->timeout_timer); timeout.sec = 0; timeout.msec = millisec; pj_time_val_normalize(&timeout); tsx_schedule_timer(tsx, &tsx->timeout_timer, &timeout, TIMEOUT_TIMER); unlock_timer(tsx); return PJ_SUCCESS; } /* * This function is called by TU to send a message. */ PJ_DEF(pj_status_t) pjsip_tsx_send_msg( pjsip_transaction *tsx, pjsip_tx_data *tdata ) { pjsip_event event; pj_status_t status; if (tdata == NULL) tdata = tsx->last_tx; PJ_ASSERT_RETURN(tdata != NULL, PJ_EINVALIDOP); PJ_LOG(5,(tsx->obj_name, "Sending %s in state %s", pjsip_tx_data_get_info(tdata), state_str[tsx->state])); pj_log_push_indent(); PJSIP_EVENT_INIT_TX_MSG(event, tdata); /* Dispatch to transaction. */ pj_grp_lock_acquire(tsx->grp_lock); /* Set transport selector to tdata */ pjsip_tx_data_set_transport(tdata, &tsx->tp_sel); /* Dispatch to state handler */ status = (*tsx->state_handler)(tsx, &event); pj_grp_lock_release(tsx->grp_lock); /* Only decrement reference counter when it returns success. * (This is the specification from the .PDF design document). */ if (status == PJ_SUCCESS) { pjsip_tx_data_dec_ref(tdata); } pj_log_pop_indent(); return status; } /* * This function is called by endpoint when incoming message for the * transaction is received. */ PJ_DEF(void) pjsip_tsx_recv_msg( pjsip_transaction *tsx, pjsip_rx_data *rdata) { pjsip_event event; PJ_LOG(5,(tsx->obj_name, "Incoming %s in state %s", pjsip_rx_data_get_info(rdata), state_str[tsx->state])); pj_log_push_indent(); /* Put the transaction in the rdata's mod_data. */ rdata->endpt_info.mod_data[mod_tsx_layer.mod.id] = tsx; /* Init event. */ PJSIP_EVENT_INIT_RX_MSG(event, rdata); /* Dispatch to transaction. */ pj_grp_lock_acquire(tsx->grp_lock); (*tsx->state_handler)(tsx, &event); pj_grp_lock_release(tsx->grp_lock); pj_log_pop_indent(); } /* Callback called by send message framework */ static void send_msg_callback( pjsip_send_state *send_state, pj_ssize_t sent, pj_bool_t *cont ) { pjsip_transaction *tsx = (pjsip_transaction*) send_state->token; pjsip_tx_data *tdata = send_state->tdata; /* Check if transaction has cancelled itself from this transmit * notification (https://trac.pjsip.org/repos/ticket/1033). * Also check if the transaction layer itself may have been shutdown * (https://trac.pjsip.org/repos/ticket/1535) */ if (mod_tsx_layer.mod.id < 0 || tdata->mod_data[mod_tsx_layer.mod.id] == NULL) { *cont = PJ_FALSE; /* Decrease pending send counter, but only if the transaction layer * hasn't been shutdown. */ if (mod_tsx_layer.mod.id >= 0) pj_grp_lock_dec_ref(tsx->grp_lock); return; } pj_grp_lock_acquire(tsx->grp_lock); /* Decrease pending send counter */ pj_grp_lock_dec_ref(tsx->grp_lock); /* Reset */ tdata->mod_data[mod_tsx_layer.mod.id] = NULL; tsx->pending_tx = NULL; if (sent > 0) { /* Successfully sent! */ pj_assert(send_state->cur_transport != NULL); if (tsx->transport != send_state->cur_transport) { /* Update transport. */ tsx_update_transport(tsx, send_state->cur_transport); /* Update remote address. */ tsx->addr_len = tdata->dest_info.addr.entry[tdata->dest_info.cur_addr].addr_len; pj_memcpy(&tsx->addr, &tdata->dest_info.addr.entry[tdata->dest_info.cur_addr].addr, tsx->addr_len); /* Update is_reliable flag. */ tsx->is_reliable = PJSIP_TRANSPORT_IS_RELIABLE(tsx->transport); } /* Clear pending transport flag. */ tsx->transport_flag &= ~(TSX_HAS_PENDING_TRANSPORT); /* Mark that we have resolved the addresses. */ tsx->transport_flag |= TSX_HAS_RESOLVED_SERVER; /* Pending destroy? */ if (tsx->transport_flag & TSX_HAS_PENDING_DESTROY) { tsx_set_state( tsx, PJSIP_TSX_STATE_DESTROYED, PJSIP_EVENT_UNKNOWN, NULL, 0 ); pj_grp_lock_release(tsx->grp_lock); return; } /* Need to transmit a message? */ if (tsx->transport_flag & TSX_HAS_PENDING_SEND) { tsx->transport_flag &= ~(TSX_HAS_PENDING_SEND); tsx_send_msg(tsx, tsx->last_tx); } /* Need to reschedule retransmission? * Note that when sending a pending message above, tsx_send_msg() * may set the flag TSX_HAS_PENDING_TRANSPORT. * Please refer to ticket #1875. */ if (tsx->transport_flag & TSX_HAS_PENDING_RESCHED && !(tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT)) { tsx->transport_flag &= ~(TSX_HAS_PENDING_RESCHED); /* Only update when transport turns out to be unreliable. */ if (!tsx->is_reliable) { tsx_resched_retransmission(tsx); } } } else { /* Failed to send! */ pj_assert(sent != 0); /* If transaction is using the same transport as the failed one, * release the transport. */ if (send_state->cur_transport==tsx->transport) tsx_update_transport(tsx, NULL); /* Also stop processing if transaction has been flagged with * pending destroy (http://trac.pjsip.org/repos/ticket/906) */ if ((!*cont) || (tsx->transport_flag & TSX_HAS_PENDING_DESTROY)) { char errmsg[PJ_ERR_MSG_SIZE]; pjsip_status_code sc; pj_str_t err; tsx->transport_err = (pj_status_t)-sent; err =pj_strerror((pj_status_t)-sent, errmsg, sizeof(errmsg)); PJ_LOG(3,(tsx->obj_name, "Failed to send %s! err=%d (%s)", pjsip_tx_data_get_info(send_state->tdata), -sent, errmsg)); /* Clear pending transport flag. */ tsx->transport_flag &= ~(TSX_HAS_PENDING_TRANSPORT); /* Mark that we have resolved the addresses. */ tsx->transport_flag |= TSX_HAS_RESOLVED_SERVER; /* Server resolution error is now mapped to 502 instead of 503, * since with 503 normally client should try again. * See http://trac.pjsip.org/repos/ticket/870 */ if (-sent==PJ_ERESOLVE || -sent==PJLIB_UTIL_EDNS_NXDOMAIN) sc = PJSIP_SC_BAD_GATEWAY; else sc = PJSIP_SC_TSX_TRANSPORT_ERROR; /* Terminate transaction, if it's not already terminated. */ tsx_set_status_code(tsx, sc, &err); if (tsx->state != PJSIP_TSX_STATE_TERMINATED && tsx->state != PJSIP_TSX_STATE_DESTROYED) { tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TRANSPORT_ERROR, send_state->tdata, 0); } /* Don't forget to destroy if we have pending destroy flag * (http://trac.pjsip.org/repos/ticket/906) */ else if (tsx->transport_flag & TSX_HAS_PENDING_DESTROY) { tsx_set_state( tsx, PJSIP_TSX_STATE_DESTROYED, PJSIP_EVENT_TRANSPORT_ERROR, send_state->tdata, 0); } } else { PJ_PERROR(3,(tsx->obj_name, (pj_status_t)-sent, "Temporary failure in sending %s, " "will try next server", pjsip_tx_data_get_info(send_state->tdata))); /* Reset retransmission count */ tsx->retransmit_count = 0; /* And reset timeout timer */ if (tsx->timeout_timer.id) { lock_timer(tsx); tsx_cancel_timer(tsx, &tsx->timeout_timer); tsx_schedule_timer( tsx, &tsx->timeout_timer, &timeout_timer_val, TIMEOUT_TIMER); unlock_timer(tsx); } /* Put again pending tdata */ tdata->mod_data[mod_tsx_layer.mod.id] = tsx; tsx->pending_tx = tdata; /* Increment group lock again for the next sending retry, * to prevent us from being destroyed prematurely (ticket #1859). */ pj_grp_lock_add_ref(tsx->grp_lock); } } pj_grp_lock_release(tsx->grp_lock); } /* Transport callback. */ static void transport_callback(void *token, pjsip_tx_data *tdata, pj_ssize_t sent) { pjsip_transaction *tsx = (pjsip_transaction*) token; /* In other circumstances, locking tsx->grp_lock AFTER transport mutex * will introduce deadlock if another thread is currently sending a * SIP message to the transport. But this should be safe as there should * be no way this callback could be called while another thread is * sending a message. */ pj_grp_lock_acquire(tsx->grp_lock); tsx->transport_flag &= ~(TSX_HAS_PENDING_TRANSPORT); pj_grp_lock_release(tsx->grp_lock); if (sent < 0) { pj_time_val delay = {0, 0}; PJ_PERROR(2,(tsx->obj_name, (pj_status_t)-sent, "Transport failed to send %s!", pjsip_tx_data_get_info(tdata))); /* Post the event for later processing, to avoid deadlock. * See https://trac.pjsip.org/repos/ticket/1646 */ lock_timer(tsx); tsx->transport_err = (pj_status_t)-sent; /* Don't cancel timeout timer if tsx state is already * PJSIP_TSX_STATE_COMPLETED (see #2076). */ if (tsx->state < PJSIP_TSX_STATE_COMPLETED) { tsx_cancel_timer(tsx, &tsx->timeout_timer); tsx_schedule_timer(tsx, &tsx->timeout_timer, &delay, TRANSPORT_ERR_TIMER); } unlock_timer(tsx); } /* Decrease pending send counter */ pj_grp_lock_dec_ref(tsx->grp_lock); } /* * Callback when transport state changes. */ static void tsx_tp_state_callback( pjsip_transport *tp, pjsip_transport_state state, const pjsip_transport_state_info *info) { PJ_UNUSED_ARG(tp); if (state == PJSIP_TP_STATE_DISCONNECTED) { pjsip_transaction *tsx; pj_time_val delay = {0, 0}; pj_assert(tp && info && info->user_data); tsx = (pjsip_transaction*)info->user_data; /* Post the event for later processing, to avoid deadlock. * See https://trac.pjsip.org/repos/ticket/1646 */ lock_timer(tsx); tsx->transport_err = info->status; /* Don't cancel timeout timer if tsx state is already * PJSIP_TSX_STATE_COMPLETED (see #2076). */ if (tsx->state < PJSIP_TSX_STATE_COMPLETED) { tsx_cancel_timer(tsx, &tsx->timeout_timer); tsx_schedule_timer(tsx, &tsx->timeout_timer, &delay, TRANSPORT_ERR_TIMER); } unlock_timer(tsx); } } /* * Send message to the transport. */ static pj_status_t tsx_send_msg( pjsip_transaction *tsx, pjsip_tx_data *tdata) { pj_status_t status = PJ_SUCCESS; PJ_ASSERT_RETURN(tsx && tdata, PJ_EINVAL); /* Send later if transport is still pending. */ if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { tsx->transport_flag |= TSX_HAS_PENDING_SEND; return PJ_SUCCESS; } /* Skip send if previous tdata transmission is pending (see #1665). */ if (tdata->is_pending) { PJ_LOG(2,(THIS_FILE, "Unable to send %s: message is pending", pjsip_tx_data_get_info(tdata))); return PJ_SUCCESS; } /* If we have the transport, send the message using that transport. * Otherwise perform full transport resolution. */ if (tsx->transport) { /* Increment group lock while waiting for send operation to complete, * to prevent us from being destroyed prematurely. See * https://trac.pjsip.org/repos/ticket/1646 */ pj_grp_lock_add_ref(tsx->grp_lock); tsx->transport_flag |= TSX_HAS_PENDING_TRANSPORT; status = pjsip_transport_send( tsx->transport, tdata, &tsx->addr, tsx->addr_len, tsx, &transport_callback); if (status == PJ_EPENDING) status = PJ_SUCCESS; else { /* Operation completes immediately */ tsx->transport_flag &= ~(TSX_HAS_PENDING_TRANSPORT); pj_grp_lock_dec_ref(tsx->grp_lock); } if (status != PJ_SUCCESS) { PJ_PERROR(2,(tsx->obj_name, status, "Error sending %s", pjsip_tx_data_get_info(tdata))); /* On error, release transport to force using full transport * resolution procedure. */ tsx_update_transport(tsx, NULL); tsx->addr_len = 0; tsx->res_addr.transport = NULL; tsx->res_addr.addr_len = 0; } else { return PJ_SUCCESS; } } /* We are here because we don't have transport, or we failed to send * the message using existing transport. If we haven't resolved the * server before, then begin the long process of resolving the server * and send the message with possibly new server. */ pj_assert(status != PJ_SUCCESS || tsx->transport == NULL); /* If we have resolved the server, we treat the error as permanent error. * Terminate transaction with transport error failure. */ if (tsx->transport_flag & TSX_HAS_RESOLVED_SERVER) { char errmsg[PJ_ERR_MSG_SIZE]; pj_str_t err; if (status == PJ_SUCCESS) { pj_assert(!"Unexpected status!"); status = PJ_EUNKNOWN; } /* We have resolved the server!. * Treat this as permanent transport error. */ err = pj_strerror(status, errmsg, sizeof(errmsg)); PJ_LOG(2,(tsx->obj_name, "Transport error, terminating transaction. " "Err=%d (%s)", status, errmsg)); tsx_set_status_code(tsx, PJSIP_SC_TSX_TRANSPORT_ERROR, &err); tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TRANSPORT_ERROR, NULL, 0 ); return status; } /* Must add reference counter because the send request functions * decrement the reference counter. */ pjsip_tx_data_add_ref(tdata); /* Also attach ourselves to the transmit data so that we'll be able * to unregister ourselves from the send notification of this * transmit data. */ tdata->mod_data[mod_tsx_layer.mod.id] = tsx; tsx->pending_tx = tdata; /* Increment group lock while waiting for send operation to complete, * to prevent us from being destroyed prematurely (ticket #1859). */ pj_grp_lock_add_ref(tsx->grp_lock); /* Begin resolving destination etc to send the message. */ if (tdata->msg->type == PJSIP_REQUEST_MSG) { tsx->transport_flag |= TSX_HAS_PENDING_TRANSPORT; status = pjsip_endpt_send_request_stateless(tsx->endpt, tdata, tsx, &send_msg_callback); if (status == PJ_EPENDING) status = PJ_SUCCESS; if (status != PJ_SUCCESS) { pj_grp_lock_dec_ref(tsx->grp_lock); pjsip_tx_data_dec_ref(tdata); tdata->mod_data[mod_tsx_layer.mod.id] = NULL; tsx->pending_tx = NULL; } /* Check if transaction is terminated. */ if (status==PJ_SUCCESS && tsx->state == PJSIP_TSX_STATE_TERMINATED) status = tsx->transport_err; } else { tsx->transport_flag |= TSX_HAS_PENDING_TRANSPORT; status = pjsip_endpt_send_response( tsx->endpt, &tsx->res_addr, tdata, tsx, &send_msg_callback); if (status == PJ_EPENDING) status = PJ_SUCCESS; if (status != PJ_SUCCESS) { pjsip_tx_data_dec_ref(tdata); tdata->mod_data[mod_tsx_layer.mod.id] = NULL; tsx->pending_tx = NULL; } /* Check if transaction is terminated. */ if (status==PJ_SUCCESS && tsx->state == PJSIP_TSX_STATE_TERMINATED) status = tsx->transport_err; } return status; } /* * Manually retransmit the last messagewithout updating the transaction state. */ PJ_DEF(pj_status_t) pjsip_tsx_retransmit_no_state(pjsip_transaction *tsx, pjsip_tx_data *tdata) { pj_status_t status; pj_grp_lock_acquire(tsx->grp_lock); if (tdata == NULL) { tdata = tsx->last_tx; pjsip_tx_data_add_ref(tdata); } status = tsx_send_msg(tsx, tdata); pj_grp_lock_release(tsx->grp_lock); /* Only decrement reference counter when it returns success. * (This is the specification from the .PDF design document). */ if (status == PJ_SUCCESS) { pjsip_tx_data_dec_ref(tdata); } return status; } /* * Retransmit last message sent. */ static void tsx_resched_retransmission( pjsip_transaction *tsx ) { pj_uint32_t msec_time; pj_assert((tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) == 0); if (tsx->role==PJSIP_ROLE_UAC && tsx->status_code >= 100) msec_time = pjsip_cfg()->tsx.t2; else msec_time = (1 << (tsx->retransmit_count)) * pjsip_cfg()->tsx.t1; if (tsx->role == PJSIP_ROLE_UAC) { pj_assert(tsx->status_code < 200); /* Retransmission for non-INVITE transaction caps-off at T2 */ if (msec_time > pjsip_cfg()->tsx.t2 && tsx->method.id != PJSIP_INVITE_METHOD) { msec_time = pjsip_cfg()->tsx.t2; } } else { /* For UAS, this can be retransmission of 2xx response for INVITE * or non-100 1xx response. */ if (tsx->status_code < 200) { /* non-100 1xx retransmission is at 60 seconds */ msec_time = PJSIP_TSX_1XX_RETRANS_DELAY * 1000; } else { /* Retransmission of INVITE final response also caps-off at T2 */ pj_assert(tsx->status_code >= 200); if (msec_time > pjsip_cfg()->tsx.t2) msec_time = pjsip_cfg()->tsx.t2; } } if (msec_time != 0) { pj_time_val timeout; timeout.sec = msec_time / 1000; timeout.msec = msec_time % 1000; tsx_schedule_timer( tsx, &tsx->retransmit_timer, &timeout, RETRANSMIT_TIMER); } } /* * Retransmit last message sent. */ static pj_status_t tsx_retransmit( pjsip_transaction *tsx, int resched) { pj_status_t status; if (resched && pj_timer_entry_running(&tsx->retransmit_timer)) { /* We've been asked to reschedule but the timer is already rerunning. * This can only happen in a race condition where, between removing * this retransmit timer from the heap and actually scheduling it, * another thread has got in and rescheduled the timer itself. In * this scenario, the transmission has already happened and so we * should just quit out immediately, without either resending the * message or restarting the timer. */ return PJ_SUCCESS; } PJ_ASSERT_RETURN(tsx->last_tx!=NULL, PJ_EBUG); PJ_LOG(5,(tsx->obj_name, "Retransmiting %s, count=%d, restart?=%d", pjsip_tx_data_get_info(tsx->last_tx), tsx->retransmit_count, resched)); ++tsx->retransmit_count; /* Restart timer T1 first before sending the message to ensure that * retransmission timer is not engaged when loop transport is used. */ if (resched) { pj_assert(tsx->state != PJSIP_TSX_STATE_CONFIRMED); if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { tsx->transport_flag |= TSX_HAS_PENDING_RESCHED; } else { tsx_resched_retransmission(tsx); } } status = tsx_send_msg( tsx, tsx->last_tx); if (status != PJ_SUCCESS) { return status; } return PJ_SUCCESS; } static void tsx_update_transport( pjsip_transaction *tsx, pjsip_transport *tp) { pj_assert(tsx); if (tsx->transport) { if (tsx->tp_st_key) { pjsip_transport_remove_state_listener(tsx->transport, tsx->tp_st_key, tsx); } pjsip_transport_dec_ref( tsx->transport ); tsx->transport = NULL; } if (tp) { tsx->transport = tp; pjsip_transport_add_ref(tp); pjsip_transport_add_state_listener(tp, &tsx_tp_state_callback, tsx, &tsx->tp_st_key); if (tp->is_shutdown) { pjsip_transport_state_info info; pj_bzero(&info, sizeof(info)); info.user_data = tsx; info.status = PJSIP_SC_TSX_TRANSPORT_ERROR; tsx_tp_state_callback(tp, PJSIP_TP_STATE_DISCONNECTED, &info); } } } /* * Handler for events in state Null. */ static pj_status_t tsx_on_state_null( pjsip_transaction *tsx, pjsip_event *event ) { pj_status_t status; pj_assert(tsx->state == PJSIP_TSX_STATE_NULL); if (tsx->role == PJSIP_ROLE_UAS) { /* Set state to Trying. */ pj_assert(event->type == PJSIP_EVENT_RX_MSG && event->body.rx_msg.rdata->msg_info.msg->type == PJSIP_REQUEST_MSG); tsx_set_state( tsx, PJSIP_TSX_STATE_TRYING, PJSIP_EVENT_RX_MSG, event->body.rx_msg.rdata, 0); } else { pjsip_tx_data *tdata; /* Must be transmit event. * You may got this assertion when using loop transport with delay * set to zero. That would cause on_rx_response() callback to be * called before tsx_send_msg() has completed. */ PJ_ASSERT_RETURN(event->type == PJSIP_EVENT_TX_MSG, PJ_EBUG); /* Get the txdata */ tdata = event->body.tx_msg.tdata; /* Save the message for retransmission. */ if (tsx->last_tx && tsx->last_tx != tdata) { pjsip_tx_data_dec_ref(tsx->last_tx); tsx->last_tx = NULL; } if (tsx->last_tx != tdata) { tsx->last_tx = tdata; pjsip_tx_data_add_ref(tdata); } /* Send the message. */ status = tsx_send_msg( tsx, tdata); if (status != PJ_SUCCESS) { return status; } /* Start Timer B (or called timer F for non-INVITE) for transaction * timeout. */ lock_timer(tsx); tsx_cancel_timer( tsx, &tsx->timeout_timer ); tsx_schedule_timer( tsx, &tsx->timeout_timer, &timeout_timer_val, TIMEOUT_TIMER); unlock_timer(tsx); /* Start Timer A (or timer E) for retransmission only if unreliable * transport is being used. */ if (!tsx->is_reliable) { tsx->retransmit_count = 0; if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { tsx->transport_flag |= TSX_HAS_PENDING_RESCHED; } else { tsx_schedule_timer(tsx, &tsx->retransmit_timer, &t1_timer_val, RETRANSMIT_TIMER); } } /* Move state. */ tsx_set_state( tsx, PJSIP_TSX_STATE_CALLING, PJSIP_EVENT_TX_MSG, tdata, 0); } return PJ_SUCCESS; } /* * State Calling is for UAC after it sends request but before any responses * is received. */ static pj_status_t tsx_on_state_calling( pjsip_transaction *tsx, pjsip_event *event ) { pj_assert(tsx->state == PJSIP_TSX_STATE_CALLING); pj_assert(tsx->role == PJSIP_ROLE_UAC); if (event->type == PJSIP_EVENT_TIMER && event->body.timer.entry == &tsx->retransmit_timer) { pj_status_t status; /* Retransmit the request. */ status = tsx_retransmit( tsx, 1 ); if (status != PJ_SUCCESS) { return status; } } else if (event->type == PJSIP_EVENT_TIMER && event->body.timer.entry == &tsx->timeout_timer) { /* Cancel retransmission timer. */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); tsx->transport_flag &= ~(TSX_HAS_PENDING_RESCHED); /* Set status code */ tsx_set_status_code(tsx, PJSIP_SC_TSX_TIMEOUT, NULL); /* Inform TU. */ tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TIMER, &tsx->timeout_timer, 0); /* Transaction is destroyed */ //return PJSIP_ETSXDESTROYED; } else if (event->type == PJSIP_EVENT_RX_MSG) { pjsip_msg *msg; int code; /* Get message instance */ msg = event->body.rx_msg.rdata->msg_info.msg; /* Better be a response message. */ if (msg->type != PJSIP_RESPONSE_MSG) return PJSIP_ENOTRESPONSEMSG; code = msg->line.status.code; /* If the response is final, cancel both retransmission and timeout * timer. */ if (code >= 200) { tsx_cancel_timer(tsx, &tsx->retransmit_timer); if (tsx->timeout_timer.id != 0) { lock_timer(tsx); tsx_cancel_timer(tsx, &tsx->timeout_timer); unlock_timer(tsx); } } else { /* Cancel retransmit timer (for non-INVITE transaction, the * retransmit timer will be rescheduled at T2. */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); /* For provisional response, only cancel retransmit when this * is an INVITE transaction. For non-INVITE, section 17.1.2.1 * of RFC 3261 says that: * - retransmit timer is set to T2 * - timeout timer F is not deleted. */ if (tsx->method.id == PJSIP_INVITE_METHOD) { /* Cancel timeout timer */ lock_timer(tsx); tsx_cancel_timer(tsx, &tsx->timeout_timer); unlock_timer(tsx); } else { if (!tsx->is_reliable) { tsx_schedule_timer(tsx, &tsx->retransmit_timer, &t2_timer_val, RETRANSMIT_TIMER); } } } tsx->transport_flag &= ~(TSX_HAS_PENDING_RESCHED); /* Discard retransmission message if it is not INVITE. * The INVITE tdata is needed in case we have to generate ACK for * the final response. */ /* Keep last_tx for authorization. */ //blp: always keep last_tx until transaction is destroyed //code = msg->line.status.code; //if (tsx->method.id != PJSIP_INVITE_METHOD && code!=401 && code!=407) { // pjsip_tx_data_dec_ref(tsx->last_tx); // tsx->last_tx = NULL; //} /* Processing is similar to state Proceeding. */ tsx_on_state_proceeding_uac( tsx, event); } else { pj_assert(!"Unexpected event"); return PJ_EBUG; } return PJ_SUCCESS; } /* * State Trying is for UAS after it received request but before any responses * is sent. * Note: this is different than RFC3261, which can use Trying state for * non-INVITE client transaction (bug in RFC?). */ static pj_status_t tsx_on_state_trying( pjsip_transaction *tsx, pjsip_event *event) { pj_status_t status; pj_assert(tsx->state == PJSIP_TSX_STATE_TRYING); /* This state is only for UAS */ pj_assert(tsx->role == PJSIP_ROLE_UAS); /* Better be transmission of response message. * If we've got request retransmission, this means that the TU hasn't * transmitted any responses within 500 ms, which is not allowed. If * this happens, just ignore the event (we couldn't retransmit last * response because we haven't sent any!). */ if (event->type != PJSIP_EVENT_TX_MSG) { return PJ_SUCCESS; } /* The rest of the processing of the event is exactly the same as in * "Proceeding" state. */ status = tsx_on_state_proceeding_uas( tsx, event); /* Inform the TU of the state transision if state is still State_Trying */ if (status==PJ_SUCCESS && tsx->state == PJSIP_TSX_STATE_TRYING) { tsx_set_state( tsx, PJSIP_TSX_STATE_PROCEEDING, PJSIP_EVENT_TX_MSG, event->body.tx_msg.tdata, 0); } return status; } /* * Handler for events in Proceeding for UAS * This state happens after the TU sends provisional response. */ static pj_status_t tsx_on_state_proceeding_uas( pjsip_transaction *tsx, pjsip_event *event) { pj_assert(tsx->state == PJSIP_TSX_STATE_PROCEEDING || tsx->state == PJSIP_TSX_STATE_TRYING); /* This state is only for UAS. */ pj_assert(tsx->role == PJSIP_ROLE_UAS); /* Receive request retransmission. */ if (event->type == PJSIP_EVENT_RX_MSG) { pj_status_t status; /* Must have last response sent. */ PJ_ASSERT_RETURN(tsx->last_tx != NULL, PJ_EBUG); /* Send last response */ if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { tsx->transport_flag |= TSX_HAS_PENDING_SEND; } else { status = tsx_send_msg(tsx, tsx->last_tx); if (status != PJ_SUCCESS) return status; } } else if (event->type == PJSIP_EVENT_TX_MSG ) { pjsip_tx_data *tdata = event->body.tx_msg.tdata; pj_status_t status; /* The TU sends response message to the request. Save this message so * that we can retransmit the last response in case we receive request * retransmission. */ pjsip_msg *msg = tdata->msg; /* This can only be a response message. */ PJ_ASSERT_RETURN(msg->type==PJSIP_RESPONSE_MSG, PJSIP_ENOTRESPONSEMSG); /* Update last status */ tsx_set_status_code(tsx, msg->line.status.code, &msg->line.status.reason); /* Discard the saved last response (it will be updated later as * necessary). */ if (tsx->last_tx && tsx->last_tx != tdata) { pjsip_tx_data_dec_ref( tsx->last_tx ); tsx->last_tx = NULL; } /* Send the message. */ status = tsx_send_msg(tsx, tdata); if (status != PJ_SUCCESS) { return status; } // Update To tag header for RFC2543 transaction. // TODO: /* Update transaction state */ if (PJSIP_IS_STATUS_IN_CLASS(tsx->status_code, 100)) { if (tsx->last_tx != tdata) { tsx->last_tx = tdata; pjsip_tx_data_add_ref( tdata ); } tsx_set_state( tsx, PJSIP_TSX_STATE_PROCEEDING, PJSIP_EVENT_TX_MSG, tdata, 0 ); /* Retransmit provisional response every 1 minute if this is * an INVITE provisional response greater than 100. */ if (PJSIP_TSX_1XX_RETRANS_DELAY > 0 && tsx->method.id==PJSIP_INVITE_METHOD && tsx->status_code>100) { /* Stop 1xx retransmission timer, if any */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); /* Schedule retransmission */ tsx->retransmit_count = 0; if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { tsx->transport_flag |= TSX_HAS_PENDING_RESCHED; } else { pj_time_val delay = {PJSIP_TSX_1XX_RETRANS_DELAY, 0}; tsx_schedule_timer( tsx, &tsx->retransmit_timer, &delay, RETRANSMIT_TIMER); } } } else if (PJSIP_IS_STATUS_IN_CLASS(tsx->status_code, 200)) { /* Stop 1xx retransmission timer, if any */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); if (tsx->method.id == PJSIP_INVITE_METHOD && tsx->handle_200resp==0) { /* 2xx class message is not saved, because retransmission * is handled by TU. */ tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TX_MSG, tdata, 0 ); /* Transaction is destroyed. */ //return PJSIP_ETSXDESTROYED; } else { pj_time_val timeout; if (tsx->method.id == PJSIP_INVITE_METHOD) { tsx->retransmit_count = 0; if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { tsx->transport_flag |= TSX_HAS_PENDING_RESCHED; } else { tsx_schedule_timer( tsx, &tsx->retransmit_timer, &t1_timer_val, RETRANSMIT_TIMER); } } /* Save last response sent for retransmission when request * retransmission is received. */ if (tsx->last_tx != tdata) { tsx->last_tx = tdata; pjsip_tx_data_add_ref(tdata); } /* Setup timeout timer: */ if (tsx->method.id == PJSIP_INVITE_METHOD) { /* Start Timer H at 64*T1 for INVITE server transaction, * regardless of transport. */ timeout = timeout_timer_val; } else if (!tsx->is_reliable) { /* For non-INVITE, start timer J at 64*T1 for unreliable * transport. */ timeout = timeout_timer_val; } else { /* Transaction terminates immediately for non-INVITE when * reliable transport is used. */ timeout.sec = timeout.msec = 0; } lock_timer(tsx); tsx_cancel_timer(tsx, &tsx->timeout_timer); tsx_schedule_timer( tsx, &tsx->timeout_timer, &timeout, TIMEOUT_TIMER); unlock_timer(tsx); /* Set state to "Completed" */ tsx_set_state( tsx, PJSIP_TSX_STATE_COMPLETED, PJSIP_EVENT_TX_MSG, tdata, 0 ); } } else if (tsx->status_code >= 300) { /* Stop 1xx retransmission timer, if any */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); /* 3xx-6xx class message causes transaction to move to * "Completed" state. */ if (tsx->last_tx != tdata) { tsx->last_tx = tdata; pjsip_tx_data_add_ref( tdata ); } /* For INVITE, start timer H for transaction termination * regardless whether transport is reliable or not. * For non-INVITE, start timer J with the value of 64*T1 for * non-reliable transports, and zero for reliable transports. */ lock_timer(tsx); tsx_cancel_timer(tsx, &tsx->timeout_timer); if (tsx->method.id == PJSIP_INVITE_METHOD) { /* Start timer H for INVITE */ tsx_schedule_timer(tsx, &tsx->timeout_timer, &timeout_timer_val, TIMEOUT_TIMER); } else if (!tsx->is_reliable) { /* Start timer J on 64*T1 seconds for non-INVITE */ tsx_schedule_timer(tsx, &tsx->timeout_timer, &timeout_timer_val, TIMEOUT_TIMER); } else { /* Start timer J on zero seconds for non-INVITE */ pj_time_val zero_time = { 0, 0 }; tsx_schedule_timer(tsx, &tsx->timeout_timer, &zero_time, TIMEOUT_TIMER); } unlock_timer(tsx); /* For INVITE, if unreliable transport is used, retransmission * timer G will be scheduled (retransmission). */ if (!tsx->is_reliable) { pjsip_cseq_hdr *cseq = (pjsip_cseq_hdr*) pjsip_msg_find_hdr( msg, PJSIP_H_CSEQ, NULL); if (cseq->method.id == PJSIP_INVITE_METHOD) { tsx->retransmit_count = 0; if (tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) { tsx->transport_flag |= TSX_HAS_PENDING_RESCHED; } else { tsx_schedule_timer(tsx, &tsx->retransmit_timer, &t1_timer_val, RETRANSMIT_TIMER); } } } /* Inform TU */ tsx_set_state( tsx, PJSIP_TSX_STATE_COMPLETED, PJSIP_EVENT_TX_MSG, tdata, 0 ); } else { pj_assert(0); } } else if (event->type == PJSIP_EVENT_TIMER && event->body.timer.entry == &tsx->retransmit_timer) { /* Retransmission timer elapsed. */ pj_status_t status; /* Must not be triggered while transport is pending. */ pj_assert((tsx->transport_flag & TSX_HAS_PENDING_TRANSPORT) == 0); /* Must have last response to retransmit. */ pj_assert(tsx->last_tx != NULL); /* Retransmit the last response. */ status = tsx_retransmit( tsx, 1 ); if (status != PJ_SUCCESS) { return status; } } else if (event->type == PJSIP_EVENT_TIMER && event->body.timer.entry == &tsx->timeout_timer) { /* Timeout timer. should not happen? */ pj_assert(!"Should not happen(?)"); tsx_set_status_code(tsx, PJSIP_SC_TSX_TIMEOUT, NULL); tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TIMER, &tsx->timeout_timer, 0); return PJ_EBUG; } else { pj_assert(!"Unexpected event"); return PJ_EBUG; } return PJ_SUCCESS; } /* * Handler for events in Proceeding for UAC * This state happens after provisional response(s) has been received from * UAS. */ static pj_status_t tsx_on_state_proceeding_uac(pjsip_transaction *tsx, pjsip_event *event) { pj_assert(tsx->state == PJSIP_TSX_STATE_PROCEEDING || tsx->state == PJSIP_TSX_STATE_CALLING); if (event->type != PJSIP_EVENT_TIMER) { pjsip_msg *msg; /* Must be incoming response, because we should not retransmit * request once response has been received. */ pj_assert(event->type == PJSIP_EVENT_RX_MSG); if (event->type != PJSIP_EVENT_RX_MSG) { return PJ_EINVALIDOP; } msg = event->body.rx_msg.rdata->msg_info.msg; /* Must be a response message. */ if (msg->type != PJSIP_RESPONSE_MSG) { pj_assert(!"Expecting response message!"); return PJSIP_ENOTRESPONSEMSG; } tsx_set_status_code(tsx, msg->line.status.code, &msg->line.status.reason); } else { if (event->body.timer.entry == &tsx->retransmit_timer) { /* Retransmit message. */ pj_status_t status; status = tsx_retransmit( tsx, 1 ); return status; } else { tsx_set_status_code(tsx, PJSIP_SC_TSX_TIMEOUT, NULL); } } if (PJSIP_IS_STATUS_IN_CLASS(tsx->status_code, 100)) { /* Inform the message to TU. */ tsx_set_state( tsx, PJSIP_TSX_STATE_PROCEEDING, PJSIP_EVENT_RX_MSG, event->body.rx_msg.rdata, 0 ); } else if (PJSIP_IS_STATUS_IN_CLASS(tsx->status_code,200)) { /* Stop timeout timer B/F. */ lock_timer(tsx); tsx_cancel_timer( tsx, &tsx->timeout_timer ); unlock_timer(tsx); /* For INVITE, the state moves to Terminated state (because ACK is * handled in TU). For non-INVITE, state moves to Completed. */ if (tsx->method.id == PJSIP_INVITE_METHOD) { tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_RX_MSG, event->body.rx_msg.rdata, 0 ); //return PJSIP_ETSXDESTROYED; } else { pj_time_val timeout; /* For unreliable transport, start timer D (for INVITE) or * timer K for non-INVITE. */ if (!tsx->is_reliable) { if (tsx->method.id == PJSIP_INVITE_METHOD) { timeout = td_timer_val; } else { timeout = t4_timer_val; } } else { timeout.sec = timeout.msec = 0; } lock_timer(tsx); tsx_schedule_timer( tsx, &tsx->timeout_timer, &timeout, TIMEOUT_TIMER); unlock_timer(tsx); /* Cancel retransmission timer */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); /* Move state to Completed, inform TU. */ tsx_set_state( tsx, PJSIP_TSX_STATE_COMPLETED, PJSIP_EVENT_RX_MSG, event->body.rx_msg.rdata, 0 ); } } else if (event->type == PJSIP_EVENT_TIMER && event->body.timer.entry == &tsx->timeout_timer) { /* Inform TU. */ tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TIMER, &tsx->timeout_timer, 0); } else if (tsx->status_code >= 300 && tsx->status_code <= 699) { #if 0 /* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */ /* * This is the old code; it's broken for authentication. */ pj_time_val timeout; pj_status_t status; /* Stop timer B. */ tsx_cancel_timer( tsx, &tsx->timeout_timer ); /* Generate and send ACK for INVITE. */ if (tsx->method.id == PJSIP_INVITE_METHOD) { pjsip_tx_data *ack; status = pjsip_endpt_create_ack( tsx->endpt, tsx->last_tx, event->body.rx_msg.rdata, &ack); if (status != PJ_SUCCESS) return status; if (ack != tsx->last_tx) { pjsip_tx_data_dec_ref(tsx->last_tx); tsx->last_tx = ack; } status = tsx_send_msg( tsx, tsx->last_tx); if (status != PJ_SUCCESS) { return status; } } /* Start Timer D with TD/T4 timer if unreliable transport is used. */ if (!tsx->is_reliable) { if (tsx->method.id == PJSIP_INVITE_METHOD) { timeout = td_timer_val; } else { timeout = t4_timer_val; } } else { timeout.sec = timeout.msec = 0; } tsx_schedule_timer( tsx, &tsx->timeout_timer, &timeout, TIMEOUT_TIMER); /* Inform TU. * blp: You might be tempted to move this notification before * sending ACK, but I think you shouldn't. Better set-up * everything before calling tsx_user's callback to avoid * mess up. */ tsx_set_state( tsx, PJSIP_TSX_STATE_COMPLETED, PJSIP_EVENT_RX_MSG, event->body.rx_msg.rdata ); /* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */ #endif /* New code, taken from 0.2.9.x branch */ pj_time_val timeout; pjsip_tx_data *ack_tdata = NULL; /* Cancel retransmission timer */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); /* Stop timer B. */ lock_timer(tsx); tsx_cancel_timer( tsx, &tsx->timeout_timer ); unlock_timer(tsx); /* Generate and send ACK (for INVITE) */ if (tsx->method.id == PJSIP_INVITE_METHOD) { pj_status_t status; status = pjsip_endpt_create_ack( tsx->endpt, tsx->last_tx, event->body.rx_msg.rdata, &ack_tdata); if (status != PJ_SUCCESS) return status; status = tsx_send_msg( tsx, ack_tdata); if (status != PJ_SUCCESS) return status; } /* Inform TU. */ tsx_set_state( tsx, PJSIP_TSX_STATE_COMPLETED, PJSIP_EVENT_RX_MSG, event->body.rx_msg.rdata, 0); /* Generate and send ACK for INVITE. */ if (tsx->method.id == PJSIP_INVITE_METHOD) { if (ack_tdata != tsx->last_tx) { pjsip_tx_data_dec_ref(tsx->last_tx); tsx->last_tx = ack_tdata; /* This is a bug. tsx_send_msg() does NOT decrement tdata's reference counter, so if we add the reference counter here, tdata will have reference counter 2, causing it to leak. pjsip_tx_data_add_ref(ack_tdata); */ } } /* Start Timer D with TD/T4 timer if unreliable transport is used. */ /* Note: tsx->transport may be NULL! */ if (!tsx->is_reliable) { if (tsx->method.id == PJSIP_INVITE_METHOD) { timeout = td_timer_val; } else { timeout = t4_timer_val; } } else { timeout.sec = timeout.msec = 0; } lock_timer(tsx); /* In the short period above timer may have been inserted * by set_timeout() (by CANCEL). Cancel it if necessary. See: * https://trac.pjsip.org/repos/ticket/1374 */ tsx_cancel_timer( tsx, &tsx->timeout_timer ); tsx_schedule_timer( tsx, &tsx->timeout_timer, &timeout, TIMEOUT_TIMER); unlock_timer(tsx); } else { // Shouldn't happen because there's no timer for this state. pj_assert(!"Unexpected event"); return PJ_EBUG; } return PJ_SUCCESS; } /* * Handler for events in Completed state for UAS */ static pj_status_t tsx_on_state_completed_uas( pjsip_transaction *tsx, pjsip_event *event) { pj_assert(tsx->state == PJSIP_TSX_STATE_COMPLETED); if (event->type == PJSIP_EVENT_RX_MSG) { pjsip_msg *msg = event->body.rx_msg.rdata->msg_info.msg; /* This must be a request message retransmission. */ if (msg->type != PJSIP_REQUEST_MSG) return PJSIP_ENOTREQUESTMSG; /* On receive request retransmission, retransmit last response. */ if (msg->line.req.method.id != PJSIP_ACK_METHOD) { pj_status_t status; status = tsx_retransmit( tsx, 0 ); if (status != PJ_SUCCESS) { return status; } } else { pj_time_val timeout; /* Process incoming ACK request. */ /* Verify that this is an INVITE transaction */ if (tsx->method.id != PJSIP_INVITE_METHOD) { PJ_LOG(2, (tsx->obj_name, "Received illegal ACK for %.*s transaction", (int)tsx->method.name.slen, tsx->method.name.ptr)); return PJSIP_EINVALIDMETHOD; } /* Cease retransmission. */ tsx_cancel_timer(tsx, &tsx->retransmit_timer); tsx->transport_flag &= ~(TSX_HAS_PENDING_RESCHED); /* Reschedule timeout timer. */ lock_timer(tsx); tsx_cancel_timer( tsx, &tsx->timeout_timer ); /* Timer I is T4 timer for unreliable transports, and * zero seconds for reliable transports. */ if (tsx->is_reliable) { timeout.sec = 0; timeout.msec = 0; } else { timeout.sec = t4_timer_val.sec; timeout.msec = t4_timer_val.msec; } tsx_schedule_timer( tsx, &tsx->timeout_timer, &timeout, TIMEOUT_TIMER); unlock_timer(tsx); /* Move state to "Confirmed" */ tsx_set_state( tsx, PJSIP_TSX_STATE_CONFIRMED, PJSIP_EVENT_RX_MSG, event->body.rx_msg.rdata, 0 ); } } else if (event->type == PJSIP_EVENT_TIMER) { if (event->body.timer.entry == &tsx->retransmit_timer) { /* Retransmit message. */ pj_status_t status; status = tsx_retransmit( tsx, 1 ); if (status != PJ_SUCCESS) { return status; } } else { if (tsx->method.id == PJSIP_INVITE_METHOD) { /* For INVITE, this means that ACK was never received. * Set state to Terminated, and inform TU. */ tsx_set_status_code(tsx, PJSIP_SC_TSX_TIMEOUT, NULL); tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TIMER, &tsx->timeout_timer, 0 ); //return PJSIP_ETSXDESTROYED; } else { /* Transaction terminated, it can now be deleted. */ tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TIMER, &tsx->timeout_timer, 0 ); //return PJSIP_ETSXDESTROYED; } } } else { /* Ignore request to transmit. */ PJ_ASSERT_RETURN(event->type == PJSIP_EVENT_TX_MSG && event->body.tx_msg.tdata == tsx->last_tx, PJ_EINVALIDOP); } return PJ_SUCCESS; } /* * Handler for events in Completed state for UAC transaction. */ static pj_status_t tsx_on_state_completed_uac( pjsip_transaction *tsx, pjsip_event *event) { pj_assert(tsx->state == PJSIP_TSX_STATE_COMPLETED); if (event->type == PJSIP_EVENT_TIMER) { /* Ignore stray retransmit event * https://trac.pjsip.org/repos/ticket/1766 */ if (event->body.timer.entry != &tsx->timeout_timer) return PJ_SUCCESS; /* Move to Terminated state. */ tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TIMER, event->body.timer.entry, 0 ); /* Transaction has been destroyed. */ //return PJSIP_ETSXDESTROYED; } else if (event->type == PJSIP_EVENT_RX_MSG) { if (tsx->method.id == PJSIP_INVITE_METHOD) { /* On received of final response retransmission, retransmit the ACK. * TU doesn't need to be informed. */ pjsip_msg *msg = event->body.rx_msg.rdata->msg_info.msg; pj_assert(msg->type == PJSIP_RESPONSE_MSG); if (msg->type==PJSIP_RESPONSE_MSG && msg->line.status.code >= 200) { pj_status_t status; status = tsx_retransmit( tsx, 0 ); if (status != PJ_SUCCESS) { return status; } } else { /* Very late retransmission of privisional response. */ pj_assert( msg->type == PJSIP_RESPONSE_MSG ); } } else { /* Just drop the response. */ } } else { pj_assert(!"Unexpected event"); return PJ_EINVALIDOP; } return PJ_SUCCESS; } /* * Handler for events in state Confirmed. */ static pj_status_t tsx_on_state_confirmed( pjsip_transaction *tsx, pjsip_event *event) { pj_assert(tsx->state == PJSIP_TSX_STATE_CONFIRMED); /* This state is only for UAS for INVITE. */ pj_assert(tsx->role == PJSIP_ROLE_UAS); pj_assert(tsx->method.id == PJSIP_INVITE_METHOD); /* Absorb any ACK received. */ if (event->type == PJSIP_EVENT_RX_MSG) { pjsip_msg *msg = event->body.rx_msg.rdata->msg_info.msg; /* Only expecting request message. */ if (msg->type != PJSIP_REQUEST_MSG) return PJSIP_ENOTREQUESTMSG; /* Must be an ACK request or a late INVITE retransmission. */ pj_assert(msg->line.req.method.id == PJSIP_ACK_METHOD || msg->line.req.method.id == PJSIP_INVITE_METHOD); } else if (event->type == PJSIP_EVENT_TIMER) { /* Ignore overlapped retransmit timer. * https://trac.pjsip.org/repos/ticket/1746 */ if (event->body.timer.entry == &tsx->retransmit_timer) { /* Ignore */ } else { /* Must be from timeout_timer_. */ pj_assert(event->body.timer.entry == &tsx->timeout_timer); /* Move to Terminated state. */ tsx_set_state( tsx, PJSIP_TSX_STATE_TERMINATED, PJSIP_EVENT_TIMER, &tsx->timeout_timer, 0 ); /* Transaction has been destroyed. */ //return PJSIP_ETSXDESTROYED; } } else { pj_assert(!"Unexpected event"); return PJ_EBUG; } return PJ_SUCCESS; } /* * Handler for events in state Terminated. */ static pj_status_t tsx_on_state_terminated( pjsip_transaction *tsx, pjsip_event *event) { pj_assert(tsx->state == PJSIP_TSX_STATE_TERMINATED); /* Ignore events other than timer. This used to be an assertion but * events may genuinely arrive at this state. */ if (event->type != PJSIP_EVENT_TIMER) { return PJ_EIGNORED; } /* Destroy this transaction */ tsx_set_state(tsx, PJSIP_TSX_STATE_DESTROYED, event->type, event->body.user.user1, 0 ); return PJ_SUCCESS; } /* * Handler for events in state Destroyed. * Shouldn't happen! */ static pj_status_t tsx_on_state_destroyed(pjsip_transaction *tsx, pjsip_event *event) { PJ_UNUSED_ARG(tsx); PJ_UNUSED_ARG(event); // See https://trac.pjsip.org/repos/ticket/1432 //pj_assert(!"Not expecting any events!!"); return PJ_EIGNORED; }