Add subscr_conn_fsm

Insert the BSCNAT's MGW into phone calls by replacing the AoIP
transport layer address IE inside BSSMAP Assignment Request and
Assignment Confirm. Accomplish this with a new subscr_conn_fsm that
parses and stores the original ass_req / ass_conf messages, communicates
with the BSCNAT MGW, and then creates new ass_req / ass_conf messages
based on the original ones but with new RTP information.

With this patch it is possible to do a successful voice call with the
following network:

  MS1 --- BTS1 --- BSC1 --.
           |        |     BSCNAT ----------- MSC
           |        |     |   |              |
           '-- MGW-BSC1 --|-- MGW-BSCNAT --- MGW-MSC
                          |   |
  MS2 --- BTS2 --- BSC2 --'   |
           |        |         |
           '-- MGW-BSC2 ------'

Related: SYS#5560
Related: https://osmocom.org/projects/osmo-bscnat/wiki/Ladder_diagrams_for_key_procedures
Change-Id: I7e491aada6f5db0eb35ef2039869c6ba07f9ca3b
This commit is contained in:
Oliver Smith 2022-04-08 17:29:10 +02:00
parent 9b5e22b2d2
commit 9b3de0183b
9 changed files with 776 additions and 0 deletions

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@ -6,5 +6,6 @@ noinst_HEADERS = \
logging.h \
msc.h \
subscr_conn.h \
subscr_conn_fsm.h \
vty.h \
$(NULL)

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@ -44,6 +44,7 @@ struct bsc_nat {
struct {
struct mgcp_client_pool *pool;
struct osmo_tdef *tdefs;
uint32_t call_id_next;
} mgw;
struct {

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@ -20,6 +20,8 @@
#pragma once
#include <osmocom/core/msgb.h>
#include <osmocom/core/sockaddr_str.h>
#include <osmocom/gsm/protocol/gsm_08_08.h>
#include <osmocom/bsc_nat/bsc_nat.h>
/* connection-less */
@ -32,3 +34,11 @@ int bssmap_tx_reset(struct bsc_nat_sccp_inst *sccp_inst, struct osmo_sccp_addr *
struct subscr_conn;
int bssap_handle_dt(enum bsc_nat_net net, struct subscr_conn *subscr_conn, struct msgb *msgb, unsigned int length);
#define bssmap_tx_assignment_failure_cn(subscr_conn, cause) \
bssmap_tx_assignment_failure(BSC_NAT_NET_CN, subscr_conn, cause)
#define bssmap_tx_assignment_failure_ran(subscr_conn, cause) \
bssmap_tx_assignment_failure(BSC_NAT_NET_RAN, subscr_conn, cause)
int bssmap_tx_assignment_failure(enum bsc_nat_net net, struct subscr_conn *subscr_conn, enum gsm0808_cause cause);
int bssmap_replace_ie_aoip_transp_addr(struct msgb **msg, struct sockaddr_storage *ss);

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@ -20,26 +20,45 @@
#pragma once
#include <osmocom/bsc_nat/bsc_nat.h>
#include <osmocom/bsc_nat/bssap.h>
/* connection for one subscriber */
struct subscr_conn {
struct llist_head list;
struct osmo_fsm_inst *fi;
struct osmo_mgcpc_ep *ep;
uint32_t mgw_call_id;
struct {
uint32_t id;
struct osmo_mgcpc_ep_ci *ci;
struct msc *msc;
} cn;
struct {
uint32_t id;
struct osmo_mgcpc_ep_ci *ci;
struct bsc *bsc;
} ran;
/* Copy of BSSMAP Assignment Request/Complete while being processed by
* subscr_conn_fsm. */
struct {
struct msgb *msg;
struct osmo_sockaddr_str aoip_transp_addr;
} ass;
};
int subscr_conn_get_next_id_ran();
int subscr_conn_get_next_id_mgw();
struct subscr_conn *subscr_conn_alloc(struct msc *msc, struct bsc *bsc, uint32_t id_cn, uint32_t id_ran);
struct subscr_conn *subscr_conn_get_by_id(uint32_t id, enum bsc_nat_net net);
int subscr_conn_rx_ass_req(struct subscr_conn *subscr_conn, const struct osmo_sockaddr_str *aoip_transp_addr,
struct msgb *msg);
int subscr_conn_rx_ass_compl(struct subscr_conn *subscr_conn, const struct osmo_sockaddr_str *aoip_transp_addr,
struct msgb *msg);
void subscr_conn_free(struct subscr_conn *subscr_conn);

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@ -0,0 +1,30 @@
/* (C) 2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
* Author: Oliver Smith <osmith@sysmocom.de>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/lienses/>.
*
*/
#pragma once
enum subscr_conn_fsm_events {
SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_REQUEST,
SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_COMPLETE,
SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_FAILURE,
SUBSCR_CONN_FSM_EV_BSSMAP_CLEAR_COMMAND,
SUBSCR_CONN_FSM_EV_MGCP_EP_OK,
SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL,
SUBSCR_CONN_FSM_EV_MGCP_EP_TERM,
};

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@ -36,6 +36,7 @@ osmo_bsc_nat_SOURCES = \
msc.c \
msc_fsm.c \
subscr_conn.c \
subscr_conn_fsm.c \
vty.c \
$(NULL)

View File

@ -23,6 +23,75 @@
#include <osmocom/sigtran/sccp_helpers.h>
#include <osmocom/bsc_nat/logging.h>
#include <osmocom/bsc_nat/subscr_conn.h>
#include <osmocom/bsc_nat/subscr_conn_fsm.h>
int bssmap_replace_ie_aoip_transp_addr(struct msgb **msg, struct sockaddr_storage *ss)
{
struct msgb *msg_new;
struct msgb *msg_old = *msg;
const struct tlv_definition *def = gsm0808_att_tlvdef();
int ofs = 1; /* first byte is bssmap message type */
int rc;
msg_new = msgb_alloc_headroom(BSSMAP_MSG_SIZE, BSSMAP_MSG_HEADROOM, talloc_get_name(msg_old));
OSMO_ASSERT(msg_new);
msgb_v_put(msg_new, msg_old->l3h[0]); /* bssmap message type */
while (ofs < msgb_l3len(msg_old)) {
int rv;
uint8_t tag;
const uint8_t *val;
uint16_t len;
rv = tlv_parse_one(&tag, &len, &val, def, &msg_old->l3h[ofs], msgb_l3len(msg_old) - ofs);
if (rv < 0) {
LOGP(DMAIN, LOGL_ERROR, "Failed to parse bssmap msg\n");
msgb_free(msg_new);
return rv;
}
if (tag == GSM0808_IE_AOIP_TRASP_ADDR)
rc = gsm0808_enc_aoip_trasp_addr(msg_new, ss);
else
rc = tlv_encode_one(msg_new, def->def[tag].type, tag, len, val);
if (rc < 0) {
LOGP(DMAIN, LOGL_ERROR, "Failed to encode tag %d into copy of bssmap msg\n", tag);
msgb_free(msg_new);
return rc;
}
ofs += rv;
}
msg_new->l3h = msgb_tv_push(msg_new, BSSAP_MSG_BSS_MANAGEMENT, msgb_length(msg_new));
msgb_free(msg_old);
*msg = msg_new;
return 0;
}
int bssmap_tx_assignment_failure(enum bsc_nat_net net, struct subscr_conn *subscr_conn, enum gsm0808_cause cause)
{
struct bsc_nat_sccp_inst *sccp_inst;
uint32_t id;
struct msgb *msg;
LOGP(DMAIN, LOGL_ERROR, "Tx BSSMAP assignment failure %s to %s via %s\n",
gsm0808_cause_name(cause),
net == BSC_NAT_NET_CN ? "CN" : "RAN",
talloc_get_name(subscr_conn));
if (net == BSC_NAT_NET_CN) {
sccp_inst = g_bsc_nat->cn.sccp_inst;
id = subscr_conn->cn.id;
} else {
sccp_inst = g_bsc_nat->ran.sccp_inst;
id = subscr_conn->ran.id;
}
msg = gsm0808_create_ass_fail(cause, NULL, NULL);
return osmo_sccp_tx_data_msg(sccp_inst->scu, id, msg);
}
static int bssap_fwd_to_cn(struct subscr_conn *subscr_conn, struct msgb *msg, unsigned int length)
{
@ -42,11 +111,131 @@ static int bssap_fwd_to_ran(struct subscr_conn *subscr_conn, struct msgb *msg, u
return osmo_sccp_tx_data(g_bsc_nat->ran.sccp_inst->scu, subscr_conn->ran.id, msg->data, msgb_length(msg));
}
static int bssmap_cn_handle_ass_req(struct subscr_conn *subscr_conn, struct msgb *msg, unsigned int length)
{
struct gsm0808_channel_type ct;
struct tlv_parsed tp;
struct sockaddr_storage ss;
struct tlv_p_entry *e;
struct osmo_sockaddr_str aoip_transp_addr;
tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, length - 1, 0, 0);
/* Get channel type */
if (!(e = TLVP_GET(&tp, GSM0808_IE_CHANNEL_TYPE))) {
LOGP(DMAIN, LOGL_ERROR, "Missing IE: channel type\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING);
return -1;
}
if (gsm0808_dec_channel_type(&ct, e->val, e->len) <= 0) {
LOGP(DMAIN, LOGL_ERROR, "Invalid IE: channel type\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_INCORRECT_VALUE);
return -1;
}
/* Not speech: fwd directly */
if ((ct.ch_indctr & 0x0f) != GSM0808_CHAN_SPEECH) {
LOGP(DMAIN, LOGL_DEBUG, "Channel type is not speech, forwarding without modification\n");
if (bssap_fwd_to_ran(subscr_conn, msg, length) < 0) {
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
return -1;
}
return 0;
}
/* Get AoIP transport layer address */
if (!(e = TLVP_GET(&tp, GSM0808_IE_AOIP_TRASP_ADDR))) {
LOGP(DMAIN, LOGL_ERROR, "Missing IE: AoIP transport layer address\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING);
return -1;
}
if (gsm0808_dec_aoip_trasp_addr(&ss, e->val, e->len) <= 0
|| osmo_sockaddr_str_from_sockaddr(&aoip_transp_addr, &ss) < 0) {
LOGP(DMAIN, LOGL_ERROR, "Invalid IE: AoIP transport layer address\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_INCORRECT_VALUE);
return -1;
}
/* Don't forward the message directly. Instead, let the subscr_conn FSM
* allocate new MGCP connections in the BSCNAT's MGW and then send a
* similar assignment request, but with the RTP address replaced. */
if (subscr_conn_rx_ass_req(subscr_conn, &aoip_transp_addr, msg) < 0) {
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
return -1;
}
return 0;
}
static void bssmap_ran_error_ass_compl(struct subscr_conn *subscr_conn, enum gsm0808_cause cause_ran)
{
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
bssmap_tx_assignment_failure_ran(subscr_conn, cause_ran);
/* For the FSM, treat this the same as if the BSC had responded with
* assignment failure. */
osmo_fsm_inst_dispatch(subscr_conn->fi, SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_FAILURE, NULL);
}
static int bssmap_ran_handle_ass_compl(struct subscr_conn *subscr_conn, struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
struct sockaddr_storage ss;
struct tlv_p_entry *e;
struct osmo_sockaddr_str aoip_transp_addr;
tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, length - 1, 0, 0);
/* Get AoIP transport layer address */
if (!(e = TLVP_GET(&tp, GSM0808_IE_AOIP_TRASP_ADDR))) {
LOGP(DMAIN, LOGL_ERROR, "Missing IE: AoIP transport layer address\n");
bssmap_ran_error_ass_compl(subscr_conn, GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING);
return -1;
}
if (gsm0808_dec_aoip_trasp_addr(&ss, e->val, e->len) <= 0
|| osmo_sockaddr_str_from_sockaddr(&aoip_transp_addr, &ss) < 0) {
LOGP(DMAIN, LOGL_ERROR, "Invalid IE: AoIP transport layer address\n");
bssmap_ran_error_ass_compl(subscr_conn, GSM0808_CAUSE_INCORRECT_VALUE);
return -1;
}
/* Don't forward the message directly. Instead, let the subscr_conn FSM
* use the RTP info to MDCX the BSC-side connection in the BSCNAT's MGW
* and then send a similar assignment complete to the MSC, but with the
* RTP address replaced. */
if (subscr_conn_rx_ass_compl(subscr_conn, &aoip_transp_addr, msg) < 0) {
bssmap_ran_error_ass_compl(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
return -1;
}
return 0;
}
static int bssmap_ran_handle_assignment_failure(struct subscr_conn *subscr_conn, struct msgb *msg, unsigned int length)
{
osmo_fsm_inst_dispatch(subscr_conn->fi, SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_FAILURE, NULL);
bssap_fwd_to_ran(subscr_conn, msg, length);
return 0;
}
static int bssmap_cn_handle_clear_cmd(struct subscr_conn *subscr_conn, struct msgb *msg, unsigned int length)
{
osmo_fsm_inst_dispatch(subscr_conn->fi, SUBSCR_CONN_FSM_EV_BSSMAP_CLEAR_COMMAND, NULL);
bssap_fwd_to_ran(subscr_conn, msg, length);
return 0;
}
static int bssmap_cn_rcvmsg_dt(struct subscr_conn *subscr_conn, struct msgb *msg, unsigned int length)
{
int ret = 0;
switch (msg->l3h[0]) {
case BSS_MAP_MSG_ASSIGNMENT_RQST:
ret = bssmap_cn_handle_ass_req(subscr_conn, msg, length);
break;
case BSS_MAP_MSG_CLEAR_CMD:
ret = bssmap_cn_handle_clear_cmd(subscr_conn, msg, length);
break;
default:
ret = bssap_fwd_to_ran(subscr_conn, msg, length);
break;
@ -60,6 +249,12 @@ static int bssmap_ran_rcvmsg_dt(struct subscr_conn *subscr_conn, struct msgb *ms
int ret = 0;
switch (msg->l3h[0]) {
case BSS_MAP_MSG_ASSIGNMENT_COMPLETE:
ret = bssmap_ran_handle_ass_compl(subscr_conn, msg, length);
break;
case BSS_MAP_MSG_ASSIGNMENT_FAILURE:
ret = bssmap_ran_handle_assignment_failure(subscr_conn, msg, length);
break;
default:
ret = bssap_fwd_to_cn(subscr_conn, msg, length);
break;

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@ -26,6 +26,8 @@
#include <osmocom/bsc_nat/subscr_conn.h>
#include <osmocom/bsc_nat/logging.h>
extern struct osmo_fsm subscr_conn_fsm;
int subscr_conn_get_next_id_ran()
{
uint32_t *id = &g_bsc_nat->ran.subscr_conn_id_next;
@ -49,6 +51,29 @@ int subscr_conn_get_next_id_ran()
return -1;
}
int subscr_conn_get_next_id_mgw()
{
uint32_t *id = &g_bsc_nat->mgw.call_id_next;
for (int i = 0; i < 0xFFFFFF; i++) {
struct subscr_conn *subscr_conn;
bool already_used = false;
*id = (*id + 1) & 0xffffff;
llist_for_each_entry(subscr_conn, &g_bsc_nat->subscr_conns, list) {
if (*id == subscr_conn->mgw_call_id) {
already_used = true;
break;
}
}
if (!already_used)
return *id;
}
return -1;
}
struct subscr_conn *subscr_conn_alloc(struct msc *msc, struct bsc *bsc, uint32_t id_cn, uint32_t id_ran)
{
struct subscr_conn *subscr_conn = talloc_zero(g_bsc_nat, struct subscr_conn);
@ -60,6 +85,9 @@ struct subscr_conn *subscr_conn_alloc(struct msc *msc, struct bsc *bsc, uint32_t
LOGP(DMAIN, LOGL_DEBUG, "Add %s\n", talloc_get_name(subscr_conn));
subscr_conn->fi = osmo_fsm_inst_alloc(&subscr_conn_fsm, subscr_conn, subscr_conn, LOGL_INFO, NULL);
OSMO_ASSERT(subscr_conn->fi);
subscr_conn->cn.id = id_cn;
subscr_conn->cn.msc = msc;
subscr_conn->ran.id = id_ran;
@ -88,5 +116,6 @@ void subscr_conn_free(struct subscr_conn *subscr_conn)
{
LOGP(DMAIN, LOGL_DEBUG, "Del %s\n", talloc_get_name(subscr_conn));
llist_del(&subscr_conn->list);
osmo_fsm_inst_free(subscr_conn->fi);
talloc_free(subscr_conn);
}

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@ -0,0 +1,490 @@
/* (C) 2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
* Author: Oliver Smith <osmith@sysmocom.de>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/lienses/>.
*
*/
#include "config.h"
#include <inttypes.h>
#include <osmocom/core/fsm.h>
#include <osmocom/gsm/gsm0808.h>
#include <osmocom/mgcp_client/mgcp_client_endpoint_fsm.h>
#include <osmocom/mgcp_client/mgcp_client_fsm.h>
#include <osmocom/sigtran/sccp_helpers.h>
#include <osmocom/bsc_nat/bsc_nat.h>
#include <osmocom/bsc_nat/bssap.h>
#include <osmocom/bsc_nat/logging.h>
#include <osmocom/bsc_nat/subscr_conn.h>
#include <osmocom/bsc_nat/subscr_conn_fsm.h>
#define X(s) (1 << (s))
#define TIMEOUT_MGW 10
#define TIMEOUT_BSC 20
enum subscr_conn_fsm_states {
SUBSCR_CONN_FSM_ST_IDLE,
SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_CRCX_CN,
SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_MDCX_CN,
SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_CRCX_RAN,
SUBSCR_CONN_FSM_ST_WAITING_FOR_ASSIGNMENT_COMPLETE,
SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_COMPLETE_MDCX_RAN,
SUBSCR_CONN_FSM_ST_WAITING_FOR_CLEAR_COMMAND,
};
static int tx_ass_req_to_ran(struct subscr_conn *subscr_conn)
{
const struct mgcp_conn_peer *rtp_info;
struct sockaddr_storage ss;
struct osmo_sockaddr_str aoip_transp_addr;
int rc;
/* Fill sockaddr_storage from rtp_info */
rtp_info = osmo_mgcpc_ep_ci_get_rtp_info(subscr_conn->ran.ci);
if (!rtp_info) {
LOGPFSML(subscr_conn->fi, LOGL_ERROR, "Failed to get RTP info from MGW, aborting assignment request\n");
return -1;
}
if (osmo_sockaddr_str_from_str(&aoip_transp_addr, rtp_info->addr, rtp_info->port) < 0
|| osmo_sockaddr_str_to_sockaddr((const struct osmo_sockaddr_str *)&aoip_transp_addr, &ss) < 0) {
LOGPFSML(subscr_conn->fi, LOGL_ERROR, "RTP info from MGW is invalid, aborting assignment request\n");
return -1;
}
if (bssmap_replace_ie_aoip_transp_addr(&subscr_conn->ass.msg, &ss) < 0) {
LOGPFSML(subscr_conn->fi, LOGL_ERROR, "Failed to replace AoIP transport layer address, aborting"
" assignment request\n");
return -1;
}
rc = osmo_sccp_tx_data_msg(g_bsc_nat->ran.sccp_inst->scu, subscr_conn->ran.id, subscr_conn->ass.msg);
subscr_conn->ass.msg = NULL;
return rc;
}
static int tx_ass_compl_to_cn(struct subscr_conn *subscr_conn)
{
const struct mgcp_conn_peer *rtp_info;
struct sockaddr_storage ss;
struct osmo_sockaddr_str aoip_transp_addr;
int rc;
/* Fill sockaddr_storage from rtp_info */
rtp_info = osmo_mgcpc_ep_ci_get_rtp_info(subscr_conn->cn.ci);
if (!rtp_info) {
LOGPFSML(subscr_conn->fi, LOGL_ERROR, "Failed to get RTP info from MGW, aborting assignment complete\n");
return -1;
}
if (osmo_sockaddr_str_from_str(&aoip_transp_addr, rtp_info->addr, rtp_info->port) < 0
|| osmo_sockaddr_str_to_sockaddr((const struct osmo_sockaddr_str *)&aoip_transp_addr, &ss) < 0) {
LOGPFSML(subscr_conn->fi, LOGL_ERROR, "RTP info from MGW is invalid, aborting assignment complete\n");
return -1;
}
if (bssmap_replace_ie_aoip_transp_addr(&subscr_conn->ass.msg, &ss) < 0) {
LOGPFSML(subscr_conn->fi, LOGL_ERROR, "Failed to replace AoIP transport layer address, aborting"
" assignment complete\n");
return -1;
}
rc = osmo_sccp_tx_data_msg(g_bsc_nat->cn.sccp_inst->scu, subscr_conn->cn.id, subscr_conn->ass.msg);
subscr_conn->ass.msg = NULL;
return rc;
}
static void st_idle_on_enter(struct osmo_fsm_inst *fi, uint32_t prev_state)
{
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
if (!subscr_conn->ep)
return;
osmo_mgcpc_ep_clear(subscr_conn->ep);
subscr_conn->ep = NULL;
subscr_conn->ran.ci = NULL;
subscr_conn->cn.ci = NULL;
}
static void st_idle(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
switch (event) {
case SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_REQUEST:
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_CRCX_CN, TIMEOUT_MGW, 0);
break;
case SUBSCR_CONN_FSM_EV_MGCP_EP_TERM:
/* This event is expected, as we terminate the MGCP EP in
* st_idle_on_enter(). Nothing to do here. */
break;
case SUBSCR_CONN_FSM_EV_BSSMAP_CLEAR_COMMAND:
/* Clear commands sent to this FSM in idle state are not
* relevant, so ignore them here. bssmap_cn_handle_clear_cmd()
* forwards them from CN to RAN. */
break;
default:
OSMO_ASSERT(false);
}
}
static void st_processing_ass_req_crcx_cn_on_enter(struct osmo_fsm_inst *fi, uint32_t prev_stat)
{
struct mgcp_client *mgcp_client;
struct mgcp_conn_peer crcx_info = {};
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
int call_id = subscr_conn_get_next_id_mgw();
if (call_id < 0) {
LOGPFSML(fi, LOGL_ERROR, "Failed to get next_id_mgw, aborting assignment request processing\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
}
/* MGCP EP */
mgcp_client = mgcp_client_pool_get(g_bsc_nat->mgw.pool);
OSMO_ASSERT(mgcp_client);
subscr_conn->ep = osmo_mgcpc_ep_alloc(subscr_conn->fi, SUBSCR_CONN_FSM_EV_MGCP_EP_TERM, mgcp_client,
g_bsc_nat->mgw.tdefs, "SUBSCR-CONN-EP",
mgcp_client_rtpbridge_wildcard(mgcp_client));
/* MGCP CRCX CN */
LOGPFSML(fi, LOGL_DEBUG, "Set MGW call_id=%d for %s\n", call_id, talloc_get_name(subscr_conn));
crcx_info.call_id = subscr_conn->mgw_call_id = call_id;
subscr_conn->cn.ci = osmo_mgcpc_ep_ci_add(subscr_conn->ep, "CI-%"PRIu32"-CN", crcx_info.call_id);
osmo_mgcpc_ep_ci_request(subscr_conn->cn.ci, MGCP_VERB_CRCX, &crcx_info, subscr_conn->fi,
SUBSCR_CONN_FSM_EV_MGCP_EP_OK, SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL, NULL);
}
static void st_processing_ass_req_crcx_cn(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
switch (event) {
case SUBSCR_CONN_FSM_EV_MGCP_EP_OK:
LOGPFSML(fi, LOGL_DEBUG, "Rx MGCP OK\n");
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_MDCX_CN, TIMEOUT_MGW, 0);
break;
case SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL:
LOGPFSML(fi, LOGL_ERROR, "MGCP failure, aborting assignment request processing\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
break;
default:
OSMO_ASSERT(false);
}
}
static void st_processing_ass_req_mdcx_cn_on_enter(struct osmo_fsm_inst *fi, uint32_t prev_stat)
{
struct mgcp_conn_peer mdcx_info = {};
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
struct osmo_sockaddr_str *addr = &subscr_conn->ass.aoip_transp_addr;
/* Set RTP addr + port */
osmo_static_assert(sizeof(mdcx_info.addr) == sizeof(addr->ip), sizeof_addr);
memcpy(mdcx_info.addr, addr->ip, sizeof(mdcx_info.addr));
mdcx_info.port = addr->port;
/* MGCP MDCX CN */
osmo_mgcpc_ep_ci_request(subscr_conn->cn.ci, MGCP_VERB_MDCX, &mdcx_info, subscr_conn->fi,
SUBSCR_CONN_FSM_EV_MGCP_EP_OK, SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL, NULL);
}
static void st_processing_ass_req_mdcx_cn(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
switch (event) {
case SUBSCR_CONN_FSM_EV_MGCP_EP_OK:
LOGPFSML(fi, LOGL_DEBUG, "Rx MGCP OK\n");
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_CRCX_RAN, TIMEOUT_MGW, 0);
break;
case SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL:
LOGPFSML(fi, LOGL_ERROR, "MGCP failure, aborting assignment request processing\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
break;
default:
OSMO_ASSERT(false);
}
}
static void st_processing_ass_req_crcx_ran_on_enter(struct osmo_fsm_inst *fi, uint32_t prev_stat)
{
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
struct mgcp_conn_peer crcx_info = {};
crcx_info.call_id = subscr_conn->mgw_call_id;
subscr_conn->ran.ci = osmo_mgcpc_ep_ci_add(subscr_conn->ep, "CI-%"PRIu32"-RAN", crcx_info.call_id);
osmo_mgcpc_ep_ci_request(subscr_conn->ran.ci, MGCP_VERB_CRCX, &crcx_info, subscr_conn->fi,
SUBSCR_CONN_FSM_EV_MGCP_EP_OK, SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL, NULL);
}
static void st_processing_ass_req_crcx_ran(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
switch (event) {
case SUBSCR_CONN_FSM_EV_MGCP_EP_OK:
LOGPFSML(fi, LOGL_DEBUG, "Rx MGCP OK\n");
if (tx_ass_req_to_ran(subscr_conn) < 0) {
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
return;
}
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_WAITING_FOR_ASSIGNMENT_COMPLETE, TIMEOUT_BSC, 0);
break;
case SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL:
LOGPFSML(fi, LOGL_ERROR, "MGCP failure, aborting assignment request processing\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
break;
default:
OSMO_ASSERT(false);
}
}
static void st_waiting_for_ass_compl(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
switch (event) {
case SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_COMPLETE:
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_COMPLETE_MDCX_RAN, TIMEOUT_MGW, 0);
break;
case SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_FAILURE:
/* The original bssmap message gets forwarded from RAN to CN by
* bssmap_ran_handle_assignment_failure() already, so just
* reset the FSM to idle here (clears the mgw endpoint). */
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
break;
default:
OSMO_ASSERT(false);
}
}
static void st_processing_ass_compl_mdcx_ran_on_enter(struct osmo_fsm_inst *fi, uint32_t prev_stat)
{
struct mgcp_conn_peer mdcx_info = {};
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
struct osmo_sockaddr_str *aoip_transp_addr = &subscr_conn->ass.aoip_transp_addr;
/* Set RTP addr + port */
osmo_static_assert(sizeof(mdcx_info.addr) == sizeof(aoip_transp_addr->ip), sizeof_addr);
memcpy(mdcx_info.addr, aoip_transp_addr->ip, sizeof(mdcx_info.addr));
mdcx_info.port = aoip_transp_addr->port;
/* MGCP MDCX RAN */
osmo_mgcpc_ep_ci_request(subscr_conn->ran.ci, MGCP_VERB_MDCX, &mdcx_info, subscr_conn->fi,
SUBSCR_CONN_FSM_EV_MGCP_EP_OK, SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL, NULL);
}
static void st_processing_ass_compl_mdcx_ran(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct subscr_conn *subscr_conn = (struct subscr_conn *)fi->priv;
switch (event) {
case SUBSCR_CONN_FSM_EV_MGCP_EP_OK:
LOGPFSML(fi, LOGL_DEBUG, "Rx MGCP EP OK\n");
if (tx_ass_compl_to_cn(subscr_conn) < 0) {
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
bssmap_tx_assignment_failure_ran(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
return;
}
/* No timeout for ST_WAITING_FOR_CLEAR_COMMAND, as the FSM will
* stay in this state until the call is done. */
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_WAITING_FOR_CLEAR_COMMAND, 0, 0);
break;
case SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL:
LOGPFSML(fi, LOGL_ERROR, "MGCP failure, aborting assignment complete processing\n");
bssmap_tx_assignment_failure_cn(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
bssmap_tx_assignment_failure_ran(subscr_conn, GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC);
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
break;
default:
OSMO_ASSERT(false);
}
}
static void st_waiting_for_clear_command(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
switch (event) {
case SUBSCR_CONN_FSM_EV_BSSMAP_CLEAR_COMMAND:
/* The original bssmap message gets forwarded from CN to RAN by
* bssmap_cn_handle_clear_cmd() already, so just reset the FSM
* to idle here (clears the mgw endpoint). */
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
break;
default:
OSMO_ASSERT(false);
}
}
int subscr_conn_fsm_timer_cb(struct osmo_fsm_inst *fi)
{
LOGPFSML(fi, LOGL_ERROR, "Timeout reached, reset FSM to idle\n");
osmo_fsm_inst_state_chg(fi, SUBSCR_CONN_FSM_ST_IDLE, 0, 0);
return 0;
}
static struct osmo_fsm_state subscr_conn_fsm_states[] = {
[SUBSCR_CONN_FSM_ST_IDLE] = {
.name = "IDLE",
.in_event_mask = 0
| X(SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_REQUEST)
| X(SUBSCR_CONN_FSM_EV_BSSMAP_CLEAR_COMMAND)
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_TERM)
,
.out_state_mask = 0
| X(SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_CRCX_CN)
,
.action = st_idle,
.onenter = st_idle_on_enter,
},
[SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_CRCX_CN] = {
.name = "PROCESSING_ASSIGNMENT_REQUEST_CRCX_CN",
.in_event_mask = 0
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_OK)
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL)
,
.out_state_mask = 0
| X(SUBSCR_CONN_FSM_ST_IDLE)
| X(SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_MDCX_CN)
,
.action = st_processing_ass_req_crcx_cn,
.onenter = st_processing_ass_req_crcx_cn_on_enter,
},
[SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_MDCX_CN] = {
.name = "PROCESSING_ASSIGNMENT_REQUEST_MDCX_CN",
.in_event_mask = 0
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_OK)
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL)
,
.out_state_mask = 0
| X(SUBSCR_CONN_FSM_ST_IDLE)
| X(SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_CRCX_RAN)
,
.action = st_processing_ass_req_mdcx_cn,
.onenter = st_processing_ass_req_mdcx_cn_on_enter,
},
[SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_REQUEST_CRCX_RAN] = {
.name = "PROCESSING_ASSIGNMENT_REQUEST_CRCX_RAN",
.in_event_mask = 0
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_OK)
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL)
,
.out_state_mask = 0
| X(SUBSCR_CONN_FSM_ST_IDLE)
| X(SUBSCR_CONN_FSM_ST_WAITING_FOR_ASSIGNMENT_COMPLETE)
,
.action = st_processing_ass_req_crcx_ran,
.onenter = st_processing_ass_req_crcx_ran_on_enter,
},
[SUBSCR_CONN_FSM_ST_WAITING_FOR_ASSIGNMENT_COMPLETE] = {
.name = "WAITING_FOR_ASSIGNMENT_COMPLETE",
.in_event_mask = 0
| X(SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_COMPLETE)
| X(SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_FAILURE)
,
.out_state_mask = 0
| X(SUBSCR_CONN_FSM_ST_IDLE)
| X(SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_COMPLETE_MDCX_RAN)
,
.action = st_waiting_for_ass_compl,
},
[SUBSCR_CONN_FSM_ST_PROCESSING_ASSIGNMENT_COMPLETE_MDCX_RAN] = {
.name = "PROCESSING_ASSIGNMENT_COMPLETE",
.in_event_mask = 0
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_OK)
| X(SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL)
,
.out_state_mask = 0
| X(SUBSCR_CONN_FSM_ST_IDLE)
| X(SUBSCR_CONN_FSM_ST_WAITING_FOR_CLEAR_COMMAND)
,
.action = st_processing_ass_compl_mdcx_ran,
.onenter = st_processing_ass_compl_mdcx_ran_on_enter,
},
[SUBSCR_CONN_FSM_ST_WAITING_FOR_CLEAR_COMMAND] = {
.name = "WAITING_FOR_CLEAR_COMMAND",
.in_event_mask = 0
| X(SUBSCR_CONN_FSM_EV_BSSMAP_CLEAR_COMMAND)
,
.out_state_mask = 0
| X(SUBSCR_CONN_FSM_ST_IDLE)
,
.action = st_waiting_for_clear_command,
},
};
const struct value_string subscr_conn_fsm_event_names[] = {
OSMO_VALUE_STRING(SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_REQUEST),
OSMO_VALUE_STRING(SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_COMPLETE),
OSMO_VALUE_STRING(SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_FAILURE),
OSMO_VALUE_STRING(SUBSCR_CONN_FSM_EV_BSSMAP_CLEAR_COMMAND),
OSMO_VALUE_STRING(SUBSCR_CONN_FSM_EV_MGCP_EP_OK),
OSMO_VALUE_STRING(SUBSCR_CONN_FSM_EV_MGCP_EP_FAIL),
OSMO_VALUE_STRING(SUBSCR_CONN_FSM_EV_MGCP_EP_TERM),
{ 0, NULL }
};
struct osmo_fsm subscr_conn_fsm = {
.name = "SUBSCR_CONN",
.states = subscr_conn_fsm_states,
.num_states = ARRAY_SIZE(subscr_conn_fsm_states),
.log_subsys = DMAIN,
.event_names = subscr_conn_fsm_event_names,
.timer_cb = subscr_conn_fsm_timer_cb,
};
static void ass_update(struct subscr_conn *subscr_conn, const struct osmo_sockaddr_str *aoip_transp_addr,
struct msgb *msg)
{
struct msgb *copy = msgb_copy_c(subscr_conn, msg, talloc_get_name(msg));
OSMO_ASSERT(copy);
if (subscr_conn->ass.msg)
msgb_free(subscr_conn->ass.msg);
subscr_conn->ass.msg = copy;
subscr_conn->ass.aoip_transp_addr = *aoip_transp_addr;
}
int subscr_conn_rx_ass_req(struct subscr_conn *subscr_conn, const struct osmo_sockaddr_str *aoip_transp_addr,
struct msgb *msg)
{
if (subscr_conn->fi->state != SUBSCR_CONN_FSM_ST_IDLE) {
LOGPFSML(subscr_conn->fi, LOGL_ERROR, "Unexpected Rx BSSMAP assignment request\n");
return -1;
}
ass_update(subscr_conn, aoip_transp_addr, msg);
return osmo_fsm_inst_dispatch(subscr_conn->fi, SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_REQUEST, NULL);
}
int subscr_conn_rx_ass_compl(struct subscr_conn *subscr_conn, const struct osmo_sockaddr_str *aoip_transp_addr,
struct msgb *msg)
{
if (subscr_conn->fi->state != SUBSCR_CONN_FSM_ST_WAITING_FOR_ASSIGNMENT_COMPLETE) {
LOGPFSML(subscr_conn->fi, LOGL_ERROR, "Unexpected Rx BSSMAP assignment complete\n");
return -1;
}
ass_update(subscr_conn, aoip_transp_addr, msg);
return osmo_fsm_inst_dispatch(subscr_conn->fi, SUBSCR_CONN_FSM_EV_BSSMAP_ASSIGNMENT_COMPLETE, NULL);
}
static __attribute__((constructor)) void subscr_conn_fsm_init(void)
{
OSMO_ASSERT(osmo_fsm_register(&subscr_conn_fsm) == 0);
}