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libosmo-sccp/src/sccp_scoc.c

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/* SCCP Connection Oriented (SCOC) according to ITU-T Q.713/Q.714 */
/* (C) 2015-2017 by Harald Welte <laforge@gnumonks.org>
* All Rights reserved
*
* SPDX-License-Identifier: GPL-2.0+
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
/* This code is a bit of a hybrid between the ITU-T Q.71x specifications
* for SCCP (particularly its connection-oriented part), and the IETF
* RFC 3868 (SUA). The idea here is to have one shared code base of the
* state machines for SCCP Connection Oriented, and use those both from
* SCCP and SUA.
*
* To do so, all SCCP messages are translated to SUA messages in the
* input side, and all generated SUA messages are translated to SCCP on
* the output side.
*
* The Choice of going for SUA messages as the "native" format was based
* on their easier parseability, and the fact that there are features in
* SUA which classic SCCP cannot handle (like IP addresses in GT).
* However, all SCCP features can be expressed in SUA.
*
* The code only supports Class 2. No support for Class 3 is intended,
* but patches are of course always welcome.
*
* Missing other features:
* * Segmentation/Reassembly support
* * T(guard) after (re)start
* * freezing of local references
* * parsing/encoding of IPv4/IPv6 addresses
* * use of multiple Routing Contexts in SUA case
*/
#include <errno.h>
#include <string.h>
#include <osmocom/core/msgb.h>
#include <osmocom/core/utils.h>
#include <osmocom/core/linuxlist.h>
#include <osmocom/core/linuxrbtree.h>
#include <osmocom/core/logging.h>
#include <osmocom/core/timer.h>
#include <osmocom/core/fsm.h>
#include <osmocom/sigtran/sccp_helpers.h>
#include <osmocom/sigtran/sccp_sap.h>
#include <osmocom/sigtran/protocol/sua.h>
#include <osmocom/sccp/sccp_types.h>
#include "xua_internal.h"
#include "sccp_internal.h"
#define S(x) (1 << (x))
#define SCU_MSGB_SIZE 1024
/***********************************************************************
* SCCP connection table
***********************************************************************/
/* a logical connection within the SCCP instance */
struct sccp_connection {
/* entry in (struct sccp_instance)->connections */
struct rb_node node;
/* which instance are we part of? */
struct osmo_sccp_instance *inst;
/* which user owns us? */
struct osmo_sccp_user *user;
/* remote point code */
uint32_t remote_pc;
/* local/remote addresses and identities */
struct osmo_sccp_addr calling_addr;
struct osmo_sccp_addr called_addr;
/* SCCP connection identifier. Only relevant across the SCCP User SAP,
* i.e. between the local application using the SCCP stack provided by
* libosmo-sccp. Never transmitted over the wire! */
uint32_t conn_id;
/* SCCP Remote Connection Reference. Allocated by the remote
* SCCP stack to uniquely identify a SCCP connection on its end.
* We don't interpret it, but simply cache it here so we can use
* it whenever sending data to the peer. Only relevant over the
* wire, not to be used across the SCCP user SAP */
uint32_t remote_ref;
uint32_t importance;
uint32_t sccp_class;
uint32_t release_cause; /* WAIT_CONN_CONF */
struct msgb *opt_data_cache;
/* incoming (true) or outgoing (false) */
bool incoming;
/* Osmo FSM Instance of sccp_scoc_fsm */
struct osmo_fsm_inst *fi;
/* Connect timer */
struct osmo_timer_list t_conn;
/* inactivity timers */
struct osmo_timer_list t_ias;
struct osmo_timer_list t_iar;
/* release timers */
struct osmo_timer_list t_rel;
struct osmo_timer_list t_int;
struct osmo_timer_list t_rep_rel;
};
/***********************************************************************
* various helper functions
***********************************************************************/
enum sccp_connection_state {
S_IDLE,
S_CONN_PEND_IN,
S_CONN_PEND_OUT,
S_ACTIVE,
S_DISCONN_PEND,
S_RESET_IN,
S_RESET_OUT,
S_BOTHWAY_RESET,
S_WAIT_CONN_CONF,
};
/* Events that this FSM can process */
enum sccp_scoc_event {
/* Primitives from SCCP-User */
SCOC_E_SCU_N_CONN_REQ,
SCOC_E_SCU_N_CONN_RESP,
SCOC_E_SCU_N_DISC_REQ,
SCOC_E_SCU_N_DATA_REQ,
SCOC_E_SCU_N_EXP_DATA_REQ,
/* Events from RCOC (Routing for Connection Oriented) */
SCOC_E_RCOC_CONN_IND,
SCOC_E_RCOC_ROUT_FAIL_IND,
SCOC_E_RCOC_RLSD_IND,
SCOC_E_RCOC_REL_COMPL_IND,
SCOC_E_RCOC_CREF_IND,
SCOC_E_RCOC_CC_IND,
SCOC_E_RCOC_DT1_IND,
SCOC_E_RCOC_DT2_IND,
SCOC_E_RCOC_IT_IND,
SCOC_E_RCOC_OTHER_NPDU,
SCOC_E_RCOC_ERROR_IND,
/* Timer Events */
SCOC_E_T_IAR_EXP,
SCOC_E_T_IAS_EXP,
SCOC_E_CONN_TMR_EXP,
SCOC_E_T_REL_EXP,
SCOC_E_T_INT_EXP,
SCOC_E_T_REP_REL_EXP,
};
static const struct value_string scoc_event_names[] = {
/* Primitives from SCCP-User */
{ SCOC_E_SCU_N_CONN_REQ, "N-CONNECT.req" },
{ SCOC_E_SCU_N_CONN_RESP, "N-CONNECT.resp" },
{ SCOC_E_SCU_N_DISC_REQ, "N-DISCONNECT.req" },
{ SCOC_E_SCU_N_DATA_REQ, "N-DATA.req" },
{ SCOC_E_SCU_N_EXP_DATA_REQ, "N-EXPEDITED_DATA.req" },
/* Events from RCOC (Routing for Connection Oriented) */
{ SCOC_E_RCOC_CONN_IND, "RCOC-CONNECT.ind" },
{ SCOC_E_RCOC_ROUT_FAIL_IND, "RCOC-ROUT_FAIL.ind" },
{ SCOC_E_RCOC_RLSD_IND, "RCOC-RELEASED.ind" },
{ SCOC_E_RCOC_REL_COMPL_IND, "RCOC-RELEASE_COMPLETE.ind" },
{ SCOC_E_RCOC_CREF_IND, "RCOC-CONNECT_REFUSED.ind" },
{ SCOC_E_RCOC_CC_IND, "RCOC-CONNECT_CONFIRM.ind" },
{ SCOC_E_RCOC_DT1_IND, "RCOC-DT1.ind" },
{ SCOC_E_RCOC_DT2_IND, "RCOC-DT2.ind" },
{ SCOC_E_RCOC_IT_IND, "RCOC-IT.ind" },
{ SCOC_E_RCOC_OTHER_NPDU, "RCOC-OTHER_NPDU.ind" },
{ SCOC_E_RCOC_ERROR_IND, "RCOC-ERROR.ind" },
{ SCOC_E_T_IAR_EXP, "T(iar)_expired" },
{ SCOC_E_T_IAS_EXP, "T(ias)_expired" },
{ SCOC_E_CONN_TMR_EXP, "T(conn)_expired" },
{ SCOC_E_T_REL_EXP, "T(rel)_expired" },
{ SCOC_E_T_INT_EXP, "T(int)_expired" },
{ SCOC_E_T_REP_REL_EXP, "T(rep_rel)_expired" },
{ 0, NULL }
};
/* how to map a SCCP CO message to an event */
static const struct xua_msg_event_map sua_scoc_event_map[] = {
{ SUA_MSGC_CO, SUA_CO_CORE, SCOC_E_RCOC_CONN_IND },
{ SUA_MSGC_CO, SUA_CO_RELRE, SCOC_E_RCOC_RLSD_IND },
{ SUA_MSGC_CO, SUA_CO_RELCO, SCOC_E_RCOC_REL_COMPL_IND },
{ SUA_MSGC_CO, SUA_CO_COREF, SCOC_E_RCOC_CREF_IND },
{ SUA_MSGC_CO, SUA_CO_COAK, SCOC_E_RCOC_CC_IND },
{ SUA_MSGC_CO, SUA_CO_CODT, SCOC_E_RCOC_DT1_IND },
{ SUA_MSGC_CO, SUA_CO_COIT, SCOC_E_RCOC_IT_IND },
{ SUA_MSGC_CO, SUA_CO_COERR, SCOC_E_RCOC_ERROR_IND },
};
/* map from SCU-primitives to SCOC FSM events */
static const struct osmo_prim_event_map scu_scoc_event_map[] = {
{ SCCP_SAP_USER, OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_REQUEST,
SCOC_E_SCU_N_CONN_REQ },
{ SCCP_SAP_USER, OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_RESPONSE,
SCOC_E_SCU_N_CONN_RESP },
{ SCCP_SAP_USER, OSMO_SCU_PRIM_N_DATA, PRIM_OP_REQUEST,
SCOC_E_SCU_N_DATA_REQ },
{ SCCP_SAP_USER, OSMO_SCU_PRIM_N_DISCONNECT, PRIM_OP_REQUEST,
SCOC_E_SCU_N_DISC_REQ },
{ SCCP_SAP_USER, OSMO_SCU_PRIM_N_EXPEDITED_DATA, PRIM_OP_REQUEST,
SCOC_E_SCU_N_EXP_DATA_REQ },
{ 0, 0, 0, OSMO_NO_EVENT }
};
/***********************************************************************
* Timer Handling
***********************************************************************/
/* Mostly pasted from Appendix C.4 of ITU-T Q.714 (05/2001) -- some of their descriptions are quite
* unintelligible out of context, for which we have our own description here. */
const struct osmo_tdef osmo_sccp_timer_defaults[OSMO_SCCP_TIMERS_LEN] = {
{ .T = OSMO_SCCP_TIMER_CONN_EST, .default_val = 1*60, .unit = OSMO_TDEF_S,
.desc = "Waiting for connection confirm message, 1 to 2 minutes" },
{ .T = OSMO_SCCP_TIMER_IAS, .default_val = 7*60, .unit = OSMO_TDEF_S,
.desc = "Send keep-alive: on an idle connection, delay before sending an Idle Timer message, 5 to 10 minutes" }, /* RFC 3868 Ch. 8. */
{ .T = OSMO_SCCP_TIMER_IAR, .default_val = 15*60, .unit = OSMO_TDEF_S,
.desc = "Receive keep-alive: on an idle connection, delay until considering a connection as stale, 11 to 21 minutes" }, /* RFC 3868 Ch. 8. */
{ .T = OSMO_SCCP_TIMER_REL, .default_val = 10, .unit = OSMO_TDEF_S,
.desc = "Waiting for release complete message, 10 to 20 seconds" },
{ .T = OSMO_SCCP_TIMER_REPEAT_REL, .default_val = 10, .unit = OSMO_TDEF_S,
.desc = "Waiting for release complete message; or to repeat sending released message after the initial expiry, 10 to 20 seconds" },
{ .T = OSMO_SCCP_TIMER_INT, .default_val = 1*60, .unit = OSMO_TDEF_S,
.desc = "Waiting for release complete message; or to release connection resources, freeze the LRN and "
"alert a maintenance function after the initial expiry, extending to 1 minute" },
{ .T = OSMO_SCCP_TIMER_GUARD, .default_val = 23*60, .unit = OSMO_TDEF_S,
.desc = "Waiting to resume normal procedure for temporary connection sections during the restart procedure, 23 to 25 minutes" },
{ .T = OSMO_SCCP_TIMER_RESET, .default_val = 10, .unit = OSMO_TDEF_S,
.desc = "Waiting to release temporary connection section or alert maintenance function after reset request message is sent, 10 to 20 seconds" },
{ .T = OSMO_SCCP_TIMER_REASSEMBLY, .default_val = 10, .unit = OSMO_TDEF_S,
.desc = "Waiting to receive all the segments of the remaining segments, single segmented message after receiving the first segment, 10 to 20 seconds" },
{}
};
/* Appendix C.4 of ITU-T Q.714 */
const struct value_string osmo_sccp_timer_names[] = {
{ OSMO_SCCP_TIMER_CONN_EST, "conn_est" },
{ OSMO_SCCP_TIMER_IAS, "ias" },
{ OSMO_SCCP_TIMER_IAR, "iar" },
{ OSMO_SCCP_TIMER_REL, "rel" },
{ OSMO_SCCP_TIMER_REPEAT_REL, "repeat_rel" },
{ OSMO_SCCP_TIMER_INT, "int" },
{ OSMO_SCCP_TIMER_GUARD, "guard" },
{ OSMO_SCCP_TIMER_RESET, "reset" },
{ OSMO_SCCP_TIMER_REASSEMBLY, "reassembly" },
{}
};
osmo_static_assert(ARRAY_SIZE(osmo_sccp_timer_defaults) == (OSMO_SCCP_TIMERS_LEN) &&
ARRAY_SIZE(osmo_sccp_timer_names) == (OSMO_SCCP_TIMERS_LEN),
assert_osmo_sccp_timers_count);
static void sccp_timer_schedule(const struct sccp_connection *conn,
struct osmo_timer_list *timer,
enum osmo_sccp_timer timer_name)
{
const unsigned long val_sec = osmo_tdef_get(conn->inst->tdefs, timer_name, OSMO_TDEF_S, -1);
osmo_timer_schedule(timer, val_sec, 0);
}
/* T(ias) has expired, send a COIT message to the peer */
static void tx_inact_tmr_cb(void *data)
{
struct sccp_connection *conn = data;
osmo_fsm_inst_dispatch(conn->fi, SCOC_E_T_IAS_EXP, NULL);
}
/* T(iar) has expired, notify the FSM about it */
static void rx_inact_tmr_cb(void *data)
{
struct sccp_connection *conn = data;
osmo_fsm_inst_dispatch(conn->fi, SCOC_E_T_IAR_EXP, NULL);
}
/* T(rel) has expired, notify the FSM about it */
static void rel_tmr_cb(void *data)
{
struct sccp_connection *conn = data;
osmo_fsm_inst_dispatch(conn->fi, SCOC_E_T_REL_EXP, NULL);
}
/* T(int) has expired, notify the FSM about it */
static void int_tmr_cb(void *data)
{
struct sccp_connection *conn = data;
osmo_fsm_inst_dispatch(conn->fi, SCOC_E_T_INT_EXP, NULL);
}
/* T(repeat_rel) has expired, notify the FSM about it */
static void rep_rel_tmr_cb(void *data)
{
struct sccp_connection *conn = data;
osmo_fsm_inst_dispatch(conn->fi, SCOC_E_T_REP_REL_EXP, NULL);
}
/* T(conn) has expired, notify the FSM about it */
static void conn_tmr_cb(void *data)
{
struct sccp_connection *conn = data;
osmo_fsm_inst_dispatch(conn->fi, SCOC_E_CONN_TMR_EXP, NULL);
}
/* Re-start the Tx inactivity timer */
static void conn_restart_tx_inact_timer(struct sccp_connection *conn)
{
sccp_timer_schedule(conn, &conn->t_ias, OSMO_SCCP_TIMER_IAS);
}
/* Re-start the Rx inactivity timer */
static void conn_restart_rx_inact_timer(struct sccp_connection *conn)
{
sccp_timer_schedule(conn, &conn->t_iar, OSMO_SCCP_TIMER_IAR);
}
/* Re-start both Rx and Tx inactivity timers */
static void conn_start_inact_timers(struct sccp_connection *conn)
{
conn_restart_tx_inact_timer(conn);
conn_restart_rx_inact_timer(conn);
}
/* Stop both Rx and Tx inactivity timers */
static void conn_stop_inact_timers(struct sccp_connection *conn)
{
osmo_timer_del(&conn->t_ias);
osmo_timer_del(&conn->t_iar);
}
/* Start release timer T(rel) */
static void conn_start_rel_timer(struct sccp_connection *conn)
{
sccp_timer_schedule(conn, &conn->t_rel, OSMO_SCCP_TIMER_REL);
}
/* Start repeat release timer T(rep_rel) */
static void conn_start_rep_rel_timer(struct sccp_connection *conn)
{
sccp_timer_schedule(conn, &conn->t_rep_rel, OSMO_SCCP_TIMER_REPEAT_REL);
}
/* Start interval timer T(int) */
static void conn_start_int_timer(struct sccp_connection *conn)
{
sccp_timer_schedule(conn, &conn->t_int, OSMO_SCCP_TIMER_INT);
}
/* Stop all release related timers: T(rel), T(int) and T(rep_rel) */
static void conn_stop_release_timers(struct sccp_connection *conn)
{
osmo_timer_del(&conn->t_rel);
osmo_timer_del(&conn->t_int);
osmo_timer_del(&conn->t_rep_rel);
}
/* Start connect timer T(conn) */
static void conn_start_connect_timer(struct sccp_connection *conn)
{
sccp_timer_schedule(conn, &conn->t_conn, OSMO_SCCP_TIMER_CONN_EST);
}
/* Stop connect timer T(conn) */
static void conn_stop_connect_timer(struct sccp_connection *conn)
{
osmo_timer_del(&conn->t_conn);
}
/***********************************************************************
* SUA Instance and Connection handling
***********************************************************************/
static void conn_destroy(struct sccp_connection *conn);
static struct sccp_connection *conn_find_by_id(const struct osmo_sccp_instance *inst, uint32_t id)
{
struct sccp_connection *conn;
const struct rb_node *node = inst->connections.rb_node;
while (node) {
conn = container_of(node, struct sccp_connection, node);
if (id < conn->conn_id)
node = node->rb_left;
else if (id > conn->conn_id)
node = node->rb_right;
else
return conn;
}
return NULL;
}
static int conn_add_node(struct osmo_sccp_instance *inst, struct sccp_connection *conn)
{
struct rb_node **n = &(inst->connections.rb_node);
struct rb_node *parent = NULL;
while (*n) {
struct sccp_connection *it;
it = container_of(*n, struct sccp_connection, node);
parent = *n;
if (conn->conn_id < it->conn_id) {
n = &((*n)->rb_left);
} else if (conn->conn_id > it->conn_id) {
n = &((*n)->rb_right);
} else {
LOGP(DLSCCP, LOGL_ERROR,
"Trying to reserve already reserved conn_id %u\n", conn->conn_id);
return -EEXIST;
}
}
rb_link_node(&conn->node, parent, n);
rb_insert_color(&conn->node, &inst->connections);
return 0;
}
bool osmo_sccp_conn_id_exists(const struct osmo_sccp_instance *inst, uint32_t id)
{
return conn_find_by_id(inst, id) ? true : false;
}
#define INIT_TIMER(x, fn, priv) do { (x)->cb = fn; (x)->data = priv; } while (0)
/* allocate + init a SCCP Connection with given ID */
static struct sccp_connection *conn_create_id(struct osmo_sccp_user *user, uint32_t conn_id)
{
struct sccp_connection *conn = talloc_zero(user->inst, struct sccp_connection);
char name[16];
conn->conn_id = conn_id;
conn->inst = user->inst;
conn->user = user;
if (conn_add_node(user->inst, conn) < 0) {
talloc_free(conn);
return NULL;
}
INIT_TIMER(&conn->t_conn, conn_tmr_cb, conn);
INIT_TIMER(&conn->t_ias, tx_inact_tmr_cb, conn);
INIT_TIMER(&conn->t_iar, rx_inact_tmr_cb, conn);
INIT_TIMER(&conn->t_rel, rel_tmr_cb, conn);
INIT_TIMER(&conn->t_int, int_tmr_cb, conn);
INIT_TIMER(&conn->t_rep_rel, rep_rel_tmr_cb, conn);
/* this might change at runtime, as it is not a constant :/ */
sccp_scoc_fsm.log_subsys = DLSCCP;
/* we simply use the connection ID as FSM instance name */
snprintf(name, sizeof(name), "%u", conn->conn_id);
conn->fi = osmo_fsm_inst_alloc(&sccp_scoc_fsm, conn, conn,
LOGL_DEBUG, name);
if (!conn->fi) {
rb_erase(&conn->node, &user->inst->connections);
talloc_free(conn);
return NULL;
}
return conn;
}
/* Return an unused SCCP connection ID.
* Callers should check the returned value: on negative return value, there are no unused IDs available.
* \param[in] sccp The SCCP instance to determine a new connection ID for.
* \return unused ID on success (range [0x0, 0x00fffffe]) or negative on elapsed max_attempts without an unused id (<0).
*/
int osmo_sccp_instance_next_conn_id(struct osmo_sccp_instance *sccp)
{
int max_attempts = 0x00FFFFFE;
/* SUA: RFC3868 sec 3.10.4:
* The source reference number is a 4 octet long integer.
* This is allocated by the source SUA instance.
* M3UA/SCCP: ITU-T Q.713 sec 3.3:
* The "source local reference" parameter field is a three-octet field containing a
* reference number which is generated and used by the local node to identify the
* connection section after the connection section is set up.
* The coding "all ones" is reserved for future use.
* Hence, as we currently use the connection ID also as local reference,
* let's simply use 24 bit ids to fit all link types (excluding 0x00ffffff).
*/
while (OSMO_LIKELY((max_attempts--) > 0)) {
/* Optimized modulo operation (% 0x00FFFFFE) using bitwise AND plus CMP: */
sccp->next_id = (sccp->next_id + 1) & 0x00FFFFFF;
if (OSMO_UNLIKELY(sccp->next_id == 0x00FFFFFF))
sccp->next_id = 0;
if (!conn_find_by_id(sccp, sccp->next_id))
return sccp->next_id;
}
return -1;
}
/* Search for next free connection ID and allocate conn */
static struct sccp_connection *conn_create(struct osmo_sccp_user *user)
{
int conn_id = osmo_sccp_instance_next_conn_id(user->inst);
if (conn_id < 0)
return NULL;
return conn_create_id(user, conn_id);
}
static void conn_opt_data_clear_cache(struct sccp_connection *conn)
{
if (conn->opt_data_cache) {
msgb_free(conn->opt_data_cache);
conn->opt_data_cache = NULL;
}
}
/* destroy a SCCP connection state, releasing all timers, terminating
* FSM and releasing associated memory */
static void conn_destroy(struct sccp_connection *conn)
{
conn_opt_data_clear_cache(conn);
conn_stop_connect_timer(conn);
conn_stop_inact_timers(conn);
conn_stop_release_timers(conn);
rb_erase(&conn->node, &conn->inst->connections);
osmo_fsm_inst_term(conn->fi, OSMO_FSM_TERM_REQUEST, NULL);
talloc_free(conn);
}
/* allocate a message buffer for an SCCP User Primitive */
static struct msgb *scu_msgb_alloc(void)
{
return msgb_alloc(SCU_MSGB_SIZE, "SCCP User Primitive");
}
/* generate a RELRE (release request) xua_msg for given conn */
static struct xua_msg *xua_gen_relre(struct sccp_connection *conn,
uint32_t cause,
struct osmo_scu_prim *prim)
{
struct xua_msg *xua = xua_msg_alloc();
if (!xua)
return NULL;
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_RELRE);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, conn->inst->route_ctx);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, conn->remote_ref);
xua_msg_add_u32(xua, SUA_IEI_SRC_REF, conn->conn_id);
xua_msg_add_u32(xua, SUA_IEI_CAUSE, SUA_CAUSE_T_RELEASE | cause);
/* optional: importance */
if (prim && msgb_l2(prim->oph.msg))
xua_msg_add_data(xua, SUA_IEI_DATA, msgb_l2len(prim->oph.msg),
msgb_l2(prim->oph.msg));
return xua;
}
/* generate xua_msg, encode it and send it to SCRC */
static int xua_gen_relre_and_send(struct sccp_connection *conn, uint32_t cause,
struct osmo_scu_prim *prim)
{
struct xua_msg *xua;
xua = xua_gen_relre(conn, cause, prim);
if (!xua)
return -1;
/* amend this with point code information; The SUA RELRE
* includes neither called nor calling party address! */
xua->mtp.dpc = conn->remote_pc;
sccp_scrc_rx_scoc_conn_msg(conn->inst, xua);
xua_msg_free(xua);
return 0;
}
/* Send cached optional data (if any) from expected message type and clear cache */
static void xua_opt_data_send_cache(struct sccp_connection *conn, int exp_type, uint8_t msg_class)
{
const struct xua_dialect *dialect = &xua_dialect_sua;
const struct xua_msg_class *xmc = dialect->class[msg_class];
if (!conn->opt_data_cache)
return;
if (conn->opt_data_cache->cb[0] != exp_type) {
/* Caller (from the FSM) knows what was the source of Optional Data we're sending.
* Compare this information with source of Optional Data recorded while caching
* to make sure we're on the same page.
*/
LOGP(DLSCCP, LOGL_ERROR, "unexpected message type %s != cache source %s\n",
xua_class_msg_name(xmc, exp_type), xua_class_msg_name(xmc, conn->opt_data_cache->cb[0]));
} else {
osmo_sccp_tx_data(conn->user, conn->conn_id, msgb_data(conn->opt_data_cache), msgb_length(conn->opt_data_cache));
}
conn_opt_data_clear_cache(conn);
}
/* Check if optional data should be dropped, log given error message if so */
static bool xua_drop_data_check_drop(const struct osmo_scu_prim *prim, unsigned lim, const char *message)
{
if (msgb_l2len(prim->oph.msg) > lim) {
LOGP(DLSCCP, LOGL_ERROR,
"%s: dropping optional data with length %u > %u - %s\n",
osmo_scu_prim_name(&prim->oph), msgb_l2len(prim->oph.msg), lim, message);
return true;
}
return false;
}
/* Cache the optional data (if necessary)
* returns true if Optional Data should be kept while encoding the message */
static bool xua_opt_data_cache_keep(struct sccp_connection *conn, const struct osmo_scu_prim *prim, int msg_type)
{
uint8_t *buf;
uint32_t max_optional_data = conn->inst->max_optional_data;
if (xua_drop_data_check_drop(prim, SCCP_MAX_DATA, "cache overrun"))
return false;
if (msgb_l2len(prim->oph.msg) > max_optional_data) {
if (conn->opt_data_cache) {
/* Caching optional data, but there already is optional data occupying the cache: */
LOGP(DLSCCP, LOGL_ERROR, "replacing unsent %u bytes of optional data cache with %s optional data\n",
msgb_length(conn->opt_data_cache), osmo_scu_prim_name(&prim->oph));
msgb_trim(conn->opt_data_cache, 0);
} else {
conn->opt_data_cache = msgb_alloc_c(conn, SCCP_MAX_DATA, "SCCP optional data cache for CR/CC/RLSD");
}
buf = msgb_put(conn->opt_data_cache, msgb_l2len(prim->oph.msg));
memcpy(buf, msgb_l2(prim->oph.msg), msgb_l2len(prim->oph.msg));
conn->opt_data_cache->cb[0] = msg_type;
return false;
}
return true;
}
/* Check optional Data size limit, cache if necessary, return indication whether original opt data should be sent */
static bool xua_opt_data_length_lim(struct sccp_connection *conn, const struct osmo_scu_prim *prim, int msg_type)
{
uint32_t max_optional_data = conn->inst->max_optional_data;
if (!(prim && msgb_l2(prim->oph.msg) && msgb_l2len(prim->oph.msg)))
return false;
switch (msg_type) {
case SUA_CO_CORE: /* §4.2 Connection request (CR) */
case SUA_CO_COAK: /* §4.3 Connection confirm (CC) */
return xua_opt_data_cache_keep(conn, prim, msg_type);
case SUA_CO_COREF: /* §4.4 Connection refused (CREF) */
if (xua_drop_data_check_drop(prim, max_optional_data, "over ITU-T Rec. Q.713 §4.4 limit")) {
/* From the state diagrams in ITU-T Rec Q.714, there's no way to send DT1 neither before nor after CREF
* at this point, so the only option we have is to drop optional data:
* see Figure C.3 / Q.714 (sheet 2 of 6) */
return false;
}
break;
case SUA_CO_RELRE: /* §4.5 Released (RLSD) */
if (msgb_l2len(prim->oph.msg) > max_optional_data) {
if (xua_drop_data_check_drop(prim, SCCP_MAX_DATA, "protocol error"))
return false;
/* There's no need to cache the optional data since the connection is still active at this point:
* Send the Optional Data in a DT1 ahead of the RLSD, because it is too large to be sent in one message.
*/
osmo_sccp_tx_data(conn->user, conn->conn_id, msgb_l2(prim->oph.msg), msgb_l2len(prim->oph.msg));
return false;
}
break;
default:
return true;
}
return true;
}
/* generate a 'struct xua_msg' of requested type from connection +
* primitive data */
static struct xua_msg *xua_gen_msg_co(struct sccp_connection *conn, uint32_t event,
const struct osmo_scu_prim *prim, int msg_type)
{
bool encode_opt_data = xua_opt_data_length_lim(conn, prim, msg_type);
struct xua_msg *xua = xua_msg_alloc();
if (!xua)
return NULL;
switch (msg_type) {
case SUA_CO_CORE: /* Connect Request == SCCP CR */
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_CORE);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, conn->inst->route_ctx);
xua_msg_add_u32(xua, SUA_IEI_PROTO_CLASS, conn->sccp_class);
xua_msg_add_u32(xua, SUA_IEI_SRC_REF, conn->conn_id);
xua_msg_add_sccp_addr(xua, SUA_IEI_DEST_ADDR, &conn->called_addr);
xua_msg_add_u32(xua, SUA_IEI_SEQ_CTRL, 0); /* TODO */
/* optional: sequence number (class 3 only) */
if (conn->calling_addr.presence)
xua_msg_add_sccp_addr(xua, SUA_IEI_SRC_ADDR, &conn->calling_addr);
/* optional: data */
if (encode_opt_data)
xua_msg_add_data(xua, SUA_IEI_DATA, msgb_l2len(prim->oph.msg), msgb_l2(prim->oph.msg));
/* optional: hop count */
/* optional: importance */
break;
case SUA_CO_COAK: /* Connect Acknowledge == SCCP CC */
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_COAK);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, conn->inst->route_ctx);
xua_msg_add_u32(xua, SUA_IEI_PROTO_CLASS, conn->sccp_class);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, conn->remote_ref);
xua_msg_add_u32(xua, SUA_IEI_SRC_REF, conn->conn_id);
xua_msg_add_u32(xua, SUA_IEI_SEQ_CTRL, 0); /* TODO */
/* optional: sequence number (class 3 only) */
if (conn->called_addr.presence)
xua_msg_add_sccp_addr(xua, SUA_IEI_SRC_ADDR, &conn->called_addr);
/* optional: hop count; importance; priority */
/* FIXME: destination address will [only] be present in
* case the CORE message conveys the source address
* parameter */
if (conn->calling_addr.presence)
xua_msg_add_sccp_addr(xua, SUA_IEI_DEST_ADDR, &conn->calling_addr);
/* optional: data */
if (encode_opt_data)
xua_msg_add_data(xua, SUA_IEI_DATA, msgb_l2len(prim->oph.msg), msgb_l2(prim->oph.msg));
/* optional: importance */
break;
case SUA_CO_RELRE: /* Release Request == SCCP RLSD */
if (!prim)
goto prim_needed;
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_RELRE);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, conn->inst->route_ctx);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, conn->remote_ref);
xua_msg_add_u32(xua, SUA_IEI_SRC_REF, conn->conn_id);
xua_msg_add_u32(xua, SUA_IEI_CAUSE, SUA_CAUSE_T_RELEASE | prim->u.disconnect.cause);
/* optional: data */
if (encode_opt_data)
xua_msg_add_data(xua, SUA_IEI_DATA, msgb_l2len(prim->oph.msg), msgb_l2(prim->oph.msg));
/* optional: importance */
break;
case SUA_CO_RELCO: /* Release Confirm == SCCP RLC */
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_RELCO);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, conn->inst->route_ctx);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, conn->remote_ref);
xua_msg_add_u32(xua, SUA_IEI_SRC_REF, conn->conn_id);
break;
case SUA_CO_CODT: /* Connection Oriented Data Transfer == SCCP DT1 */
if (!prim)
goto prim_needed;
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_CODT);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, conn->inst->route_ctx);
/* Sequence number only in expedited data */
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, conn->remote_ref);
/* optional: priority; correlation id */
xua_msg_add_data(xua, SUA_IEI_DATA, msgb_l2len(prim->oph.msg),
msgb_l2(prim->oph.msg));
break;
case SUA_CO_COIT: /* Connection Oriented Interval Timer == SCCP IT */
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_COIT);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, conn->inst->route_ctx);
xua_msg_add_u32(xua, SUA_IEI_PROTO_CLASS, conn->sccp_class);
xua_msg_add_u32(xua, SUA_IEI_SRC_REF, conn->conn_id);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, conn->remote_ref);
/* optional: sequence number; credit (both class 3 only) */
break;
case SUA_CO_COREF: /* Connect Refuse == SCCP CREF */
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_COREF);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, conn->inst->route_ctx);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, conn->remote_ref);
//xua_msg_add_u32(xua, SUA_IEI_CAUSE, SUA_CAUSE_T_REFUSAL | prim->u.disconnect.cause);
xua_msg_add_u32(xua, SUA_IEI_CAUSE, SUA_CAUSE_T_REFUSAL | SCCP_REFUSAL_UNEQUIPPED_USER);
/* optional: source addr */
if (conn->called_addr.presence)
xua_msg_add_sccp_addr(xua, SUA_IEI_SRC_ADDR, &conn->called_addr);
/* conditional: dest addr */
if (conn->calling_addr.presence)
xua_msg_add_sccp_addr(xua, SUA_IEI_DEST_ADDR, &conn->calling_addr);
/* optional: data */
if (encode_opt_data)
xua_msg_add_data(xua, SUA_IEI_DATA, msgb_l2len(prim->oph.msg), msgb_l2(prim->oph.msg));
/* optional: importance */
break;
/* FIXME */
default:
LOGP(DLSCCP, LOGL_ERROR, "Don't know how to encode msg_type %u\n", msg_type);
xua_msg_free(xua);
return NULL;
}
return xua;
prim_needed:
xua_msg_free(xua);
LOGP(DLSCCP, LOGL_ERROR, "%s must be called with valid 'prim' "
"pointer for msg_type=%u\n", __func__, msg_type);
return NULL;
}
/* generate xua_msg, encode it and send it to SCRC
* returns 0 on success, negative on error
*/
static int xua_gen_encode_and_send(struct sccp_connection *conn, uint32_t event,
const struct osmo_scu_prim *prim, int msg_type)
{
struct xua_msg *xua;
xua = xua_gen_msg_co(conn, event, prim, msg_type);
if (!xua)
return -ENOMEM;
/* amend this with point code information; Many CO msgs
* includes neither called nor calling party address! */
xua->mtp.dpc = conn->remote_pc;
sccp_scrc_rx_scoc_conn_msg(conn->inst, xua);
xua_msg_free(xua);
return 0;
}
/* allocate a SCU primitive to be sent to the user */
static struct osmo_scu_prim *scu_prim_alloc(unsigned int primitive, enum osmo_prim_operation operation)
{
struct msgb *upmsg = scu_msgb_alloc();
struct osmo_scu_prim *prim;
prim = (struct osmo_scu_prim *) msgb_put(upmsg, sizeof(*prim));
osmo_prim_init(&prim->oph, SCCP_SAP_USER,
primitive, operation, upmsg);
upmsg->l2h = upmsg->tail;
return prim;
}
/* high-level function to generate a SCCP User primitive of requested
* type based on the connection and currently processed XUA message */
static void scu_gen_encode_and_send(struct sccp_connection *conn, uint32_t event,
struct xua_msg *xua, unsigned int primitive,
enum osmo_prim_operation operation)
{
struct osmo_scu_prim *scu_prim;
struct osmo_scu_disconn_param *udisp;
struct osmo_scu_connect_param *uconp;
struct osmo_scu_data_param *udatp;
struct xua_msg_part *data_ie;
scu_prim = scu_prim_alloc(primitive, operation);
switch (OSMO_PRIM_HDR(&scu_prim->oph)) {
case OSMO_PRIM(OSMO_SCU_PRIM_N_DISCONNECT, PRIM_OP_INDICATION):
udisp = &scu_prim->u.disconnect;
udisp->conn_id = conn->conn_id;
udisp->responding_addr = conn->called_addr;
udisp->importance = conn->importance;
udisp->originator = OSMO_SCCP_ORIG_UNDEFINED;
//udisp->in_sequence_control;
if (xua) {
udisp->cause = xua_msg_get_u32(xua, SUA_IEI_CAUSE);
if (xua_msg_find_tag(xua, SUA_IEI_SRC_ADDR))
sua_addr_parse(&udisp->responding_addr, xua, SUA_IEI_SRC_ADDR);
data_ie = xua_msg_find_tag(xua, SUA_IEI_DATA);
udisp->importance = xua_msg_get_u32(xua, SUA_IEI_IMPORTANCE);
if (data_ie) {
struct msgb *upmsg = scu_prim->oph.msg;
upmsg->l2h = msgb_put(upmsg, data_ie->len);
memcpy(upmsg->l2h, data_ie->dat, data_ie->len);
}
}
break;
case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_INDICATION):
uconp = &scu_prim->u.connect;
uconp->conn_id = conn->conn_id;
uconp->called_addr = conn->called_addr;
uconp->calling_addr = conn->calling_addr;
uconp->sccp_class = conn->sccp_class;
uconp->importance = conn->importance;
if (xua) {
data_ie = xua_msg_find_tag(xua, SUA_IEI_DATA);
if (data_ie) {
struct msgb *upmsg = scu_prim->oph.msg;
upmsg->l2h = msgb_put(upmsg, data_ie->len);
memcpy(upmsg->l2h, data_ie->dat, data_ie->len);
}
}
break;
case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_CONFIRM):
uconp = &scu_prim->u.connect;
uconp->conn_id = conn->conn_id;
uconp->called_addr = conn->called_addr;
uconp->calling_addr = conn->calling_addr;
//scu_prim->u.connect.in_sequence_control
uconp->sccp_class = xua_msg_get_u32(xua, SUA_IEI_PROTO_CLASS) & 3;
uconp->importance = xua_msg_get_u32(xua, SUA_IEI_IMPORTANCE);
data_ie = xua_msg_find_tag(xua, SUA_IEI_DATA);
if (data_ie) {
struct msgb *upmsg = scu_prim->oph.msg;
upmsg->l2h = msgb_put(upmsg, data_ie->len);
memcpy(upmsg->l2h, data_ie->dat, data_ie->len);
}
break;
case OSMO_PRIM(OSMO_SCU_PRIM_N_DATA, PRIM_OP_INDICATION):
udatp = &scu_prim->u.data;
udatp->conn_id = conn->conn_id;
udatp->importance = conn->importance;
data_ie = xua_msg_find_tag(xua, SUA_IEI_DATA);
if (data_ie) {
struct msgb *upmsg = scu_prim->oph.msg;
upmsg->l2h = msgb_put(upmsg, data_ie->len);
memcpy(upmsg->l2h, data_ie->dat, data_ie->len);
}
break;
default:
LOGPFSML(conn->fi, LOGL_ERROR, "Unsupported primitive %u:%u\n",
scu_prim->oph.primitive, scu_prim->oph.operation);
talloc_free(scu_prim->oph.msg);
return;
}
sccp_user_prim_up(conn->user, scu_prim);
}
/***********************************************************************
* Actual SCCP Connection Oriented Control (SCOC) Finite State Machine
***********************************************************************/
/* Figure C.2/Q.714 (sheet 1 of 7) and C.3/Q.714 (sheet 1 of 6) */
static void scoc_fsm_idle(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct sccp_connection *conn = fi->priv;
struct osmo_scu_prim *prim = NULL;
struct osmo_scu_connect_param *uconp;
struct xua_msg *xua = NULL;
int rc;
switch (event) {
case SCOC_E_SCU_N_CONN_REQ:
prim = data;
uconp = &prim->u.connect;
/* copy relevant parameters from prim to conn */
conn->called_addr = uconp->called_addr;
conn->calling_addr = uconp->calling_addr;
conn->sccp_class = uconp->sccp_class;
/* generate + send CR PDU to SCRC */
rc = xua_gen_encode_and_send(conn, event, prim, SUA_CO_CORE);
if (rc < 0)
LOGPFSML(fi, LOGL_ERROR, "Failed to initiate connection: %s\n", strerror(-rc));
else {
/* start connection timer */
conn_start_connect_timer(conn);
osmo_fsm_inst_state_chg(fi, S_CONN_PEND_OUT, 0, 0);
}
break;
#if 0
case SCOC_E_SCU_N_TYPE1_REQ:
/* ?!? */
break;
#endif
case SCOC_E_RCOC_RLSD_IND:
/* send release complete to SCRC */
xua_gen_encode_and_send(conn, event, NULL, SUA_CO_RELCO);
break;
case SCOC_E_RCOC_REL_COMPL_IND:
/* do nothing */
break;
case SCOC_E_RCOC_OTHER_NPDU:
#if 0
if (src_ref) {
/* FIXME: send ERROR to SCRC */
}
#endif
break;
/* destination node / incoming connection */
/* Figure C.3 / Q.714 (sheet 1 of 6) */
case SCOC_E_RCOC_CONN_IND:
xua = data;
/* copy relevant parameters from xua to conn */
sua_addr_parse(&conn->calling_addr, xua, SUA_IEI_SRC_ADDR);
sua_addr_parse(&conn->called_addr, xua, SUA_IEI_DEST_ADDR);
conn->remote_ref = xua_msg_get_u32(xua, SUA_IEI_SRC_REF);
conn->sccp_class = xua_msg_get_u32(xua, SUA_IEI_PROTO_CLASS) & 3;
conn->importance = xua_msg_get_u32(xua, SUA_IEI_IMPORTANCE);
/* 3.1.6.1 The originating node of the CR message
* (identified by the OPC in the calling party address
* or by default by the OPC in the MTP label, [and the
* MTP-SAP instance]) is associated with the incoming
* connection section. */
if (conn->calling_addr.presence & OSMO_SCCP_ADDR_T_PC)
conn->remote_pc = conn->calling_addr.pc;
else {
/* Hack to get the MTP label here ?!? */
conn->remote_pc = xua->mtp.opc;
}
osmo_fsm_inst_state_chg(fi, S_CONN_PEND_IN, 0, 0);
/* N-CONNECT.ind to User */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_CONNECT,
PRIM_OP_INDICATION);
break;
}
}
static void scoc_fsm_idle_onenter(struct osmo_fsm_inst *fi, uint32_t old_state)
{
conn_destroy(fi->priv);
}
/* Figure C.3 / Q.714 (sheet 2 of 6) */
static void scoc_fsm_conn_pend_in(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct sccp_connection *conn = fi->priv;
struct osmo_scu_prim *prim = NULL;
switch (event) {
case SCOC_E_SCU_N_CONN_RESP:
prim = data;
/* FIXME: assign local reference (only now?) */
/* FIXME: assign sls, protocol class and credit */
xua_gen_encode_and_send(conn, event, prim, SUA_CO_COAK);
/* start inactivity timers */
conn_start_inact_timers(conn);
osmo_fsm_inst_state_chg(fi, S_ACTIVE, 0, 0);
xua_opt_data_send_cache(conn, SUA_CO_COAK, SUA_MSGC_CO);
break;
case SCOC_E_SCU_N_DISC_REQ:
prim = data;
/* release resources: implicit */
xua_gen_encode_and_send(conn, event, prim, SUA_CO_COREF);
/* N. B: we've ignored CREF sending errors as there's no recovery option anyway */
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
}
}
/* Figure C.2/Q.714 (sheet 2 of 7) */
static void scoc_fsm_conn_pend_out(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct sccp_connection *conn = fi->priv;
struct osmo_scu_prim *prim = NULL;
struct xua_msg *xua = NULL;
switch (event) {
case SCOC_E_SCU_N_DISC_REQ:
prim = data;
conn->release_cause = prim->u.disconnect.cause;
osmo_fsm_inst_state_chg(fi, S_WAIT_CONN_CONF, 0, 0);
/* keep conn timer running(!) */
break;
case SCOC_E_CONN_TMR_EXP:
/* N-DISCONNECT.ind to user */
scu_gen_encode_and_send(conn, event, NULL, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
/* below implicitly releases resources + local ref */
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_RCOC_ROUT_FAIL_IND:
case SCOC_E_RCOC_CREF_IND:
xua = data;
/* stop conn timer */
conn_stop_connect_timer(conn);
/* release local res + ref (implicit by going to idle) */
/* N-DISCONNECT.ind to user */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
/* below implicitly releases resources + local ref */
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_RCOC_RLSD_IND:
xua = data;
/* RLC to SCRC */
xua_gen_encode_and_send(conn, event, NULL, SUA_CO_RELCO);
/* stop conn timer */
conn_stop_connect_timer(conn);
/* release local res + ref (implicit) */
/* N-DISCONNECT.ind to user */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_RCOC_OTHER_NPDU:
xua = data;
conn_start_connect_timer(conn);
/* release local res + ref (implicit) */
/* N-DISCONNECT.ind to user */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_RCOC_CC_IND:
xua = data;
/* stop conn timer */
conn_stop_connect_timer(conn);
/* start inactivity timers */
conn_start_inact_timers(conn);
/* TODO: assign PCU and credit */
/* associate remote ref to conn */
conn->remote_ref = xua_msg_get_u32(xua, SUA_IEI_SRC_REF);
/* 3.1.4.2 The node sending the CC message (identified
* by the parameter OPC contained in the
* MTP-TRANSFER.indication primitive which conveyed the
* CC message [plus the MTP-SAP instance]) is associated
* with the connection section. */
conn->remote_pc = xua->mtp.opc;
osmo_fsm_inst_state_chg(fi, S_ACTIVE, 0, 0);
/* If CR which was used to initiate this connection had excessive Optional Data which we had to cache,
* now is the time to send it: the connection is already active but we hadn't notified upper layers about it
* so we have the connection all to ourselves and can use it to transmit "leftover" data via DT1 */
xua_opt_data_send_cache(conn, SUA_CO_CORE, xua->hdr.msg_class);
/* N-CONNECT.conf to user */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_CONNECT,
PRIM_OP_CONFIRM);
break;
}
}
/* Figure C.2/Q.714 (sheet 3 of 7) */
static void scoc_fsm_wait_conn_conf(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct sccp_connection *conn = fi->priv;
struct xua_msg *xua = NULL;
switch (event) {
case SCOC_E_RCOC_RLSD_IND:
xua = data;
/* release complete to SCRC */
xua_gen_encode_and_send(conn, event, NULL, SUA_CO_RELCO);
/* stop conn timer */
conn_stop_connect_timer(conn);
/* release local res + ref (implicit) */
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_RCOC_CC_IND:
xua = data;
/* stop conn timer */
conn_stop_connect_timer(conn);
/* associate rem ref to conn */
conn->remote_ref = xua_msg_get_u32(xua, SUA_IEI_SRC_REF);
/* 3.1.4.2 The node sending the CC message (identified
* by the parameter OPC contained in the
* MTP-TRANSFER.indication primitive which conveyed the
* CC message [plus the MTP-SAP instance]) is associated
* with the connection section. */
conn->remote_pc = xua->mtp.opc;
/* released to SCRC */
xua_gen_relre_and_send(conn, conn->release_cause, NULL);
/* start rel timer */
conn_start_rel_timer(conn);
osmo_fsm_inst_state_chg(fi, S_DISCONN_PEND, 0, 0);
break;
case SCOC_E_RCOC_OTHER_NPDU:
case SCOC_E_RCOC_CREF_IND:
case SCOC_E_RCOC_ROUT_FAIL_IND:
xua = data;
/* stop conn timer */
conn_stop_connect_timer(conn);
/* release local res + ref */
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_CONN_TMR_EXP:
/* release local res + ref */
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
}
}
/* C.2/Q.714 (sheet 4+5 of 7) and C.3/Q714 (sheet 3+4 of 6) */
static void scoc_fsm_active(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct xua_msg *xua = data;
struct sccp_connection *conn = fi->priv;
struct osmo_scu_prim *prim = NULL;
switch (event) {
#pragma message ("TODO: internal disco: send N-DISCONNECT.ind to user")
/* send N-DISCONNECT.ind to user */
/*scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);*/
/* fall-through */
case SCOC_E_SCU_N_DISC_REQ:
prim = data;
/* stop inact timers */
conn_stop_inact_timers(conn);
/* send RLSD to SCRC */
xua_gen_encode_and_send(conn, event, prim, SUA_CO_RELRE);
/* start rel timer */
conn_start_rel_timer(conn);
osmo_fsm_inst_state_chg(fi, S_DISCONN_PEND, 0, 0);
break;
case SCOC_E_RCOC_CREF_IND:
case SCOC_E_RCOC_CC_IND:
case SCOC_E_RCOC_REL_COMPL_IND:
/* do nothing */
break;
case SCOC_E_RCOC_RLSD_IND:
/* send N-DISCONNECT.ind to user */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
/* release res + local ref (implicit) */
/* stop inact timers */
conn_stop_inact_timers(conn);
/* RLC to SCRC */
xua_gen_encode_and_send(conn, event, NULL, SUA_CO_RELCO);
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_RCOC_ERROR_IND:
xua = data;
/* FIXME: check for cause service_class_mismatch */
/* release res + local ref (implicit) */
/* send N-DISCONNECT.ind to user */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
/* stop inact timers */
conn_stop_inact_timers(conn);
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_T_IAR_EXP:
/* stop inact timers */
conn_stop_inact_timers(conn);
xua = xua_msg_alloc();
xua_msg_add_u32(xua, SUA_IEI_CAUSE,
SUA_CAUSE_T_RELEASE | SCCP_RELEASE_CAUSE_EXPIRATION_INACTIVE);
xua_msg_add_u32(xua, SUA_IEI_IMPORTANCE, conn->importance);
/* Send N-DISCONNECT.ind to local user */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
talloc_free(xua);
/* Send RLSD to peer */
xua_gen_relre_and_send(conn, SCCP_RELEASE_CAUSE_EXPIRATION_INACTIVE, NULL);
/* start release timer */
conn_start_rel_timer(conn);
osmo_fsm_inst_state_chg(fi, S_DISCONN_PEND, 0, 0);
break;
case SCOC_E_RCOC_ROUT_FAIL_IND:
/* send N-DISCONNECT.ind to user */
scu_gen_encode_and_send(conn, event, NULL, OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
/* stop inact timers */
conn_stop_inact_timers(conn);
/* start release timer */
conn_start_rel_timer(conn);
osmo_fsm_inst_state_chg(fi, S_DISCONN_PEND, 0, 0);
break;
/* Figure C.4/Q.714 */
case SCOC_E_SCU_N_DATA_REQ:
case SCOC_E_SCU_N_EXP_DATA_REQ:
prim = data;
xua_gen_encode_and_send(conn, event, prim, SUA_CO_CODT);
conn_restart_tx_inact_timer(conn);
break;
case SCOC_E_RCOC_DT1_IND:
/* restart receive inactivity timer */
conn_restart_rx_inact_timer(conn);
/* TODO: M-bit */
scu_gen_encode_and_send(conn, event, xua, OSMO_SCU_PRIM_N_DATA,
PRIM_OP_INDICATION);
break;
/* Figure C.4/Q.714 (sheet 4 of 4) */
case SCOC_E_RCOC_IT_IND:
xua = data;
/* check if remote reference is what we expect */
/* check class is what we expect */
if (xua_msg_get_u32(xua, SUA_IEI_SRC_REF) != conn->remote_ref ||
xua_msg_get_u32(xua, SUA_IEI_PROTO_CLASS) != conn->sccp_class) {
/* Release connection */
/* Stop inactivity Timers */
conn_stop_inact_timers(conn);
xua = xua_msg_alloc();
xua_msg_add_u32(xua, SUA_IEI_CAUSE,
SUA_CAUSE_T_RELEASE | SCCP_RELEASE_CAUSE_INCONSISTENT_CONN_DATA);
xua_msg_add_u32(xua, SUA_IEI_IMPORTANCE, conn->importance);
/* send N-DISCONNECT.ind to user */
scu_gen_encode_and_send(conn, event, xua,
OSMO_SCU_PRIM_N_DISCONNECT,
PRIM_OP_INDICATION);
talloc_free(xua);
/* Send RLSD to SCRC */
xua_gen_relre_and_send(conn, SCCP_RELEASE_CAUSE_INCONSISTENT_CONN_DATA, NULL);
talloc_free(xua);
/* Start release timer */
conn_start_rel_timer(conn);
osmo_fsm_inst_state_chg(fi, S_DISCONN_PEND, 0, 0);
}
conn_restart_rx_inact_timer(conn);
break;
case SCOC_E_T_IAS_EXP:
/* Send IT to peer */
xua_gen_encode_and_send(conn, event, NULL, SUA_CO_COIT);
conn_restart_tx_inact_timer(conn);
break;
}
}
/* C.2/Q.714 (sheet 6+7 of 7) and C.3/Q.714 (sheet 5+6 of 6) */
static void scoc_fsm_disconn_pend(struct osmo_fsm_inst *fi, uint32_t event, void *data)
{
struct sccp_connection *conn = fi->priv;
switch (event) {
case SCOC_E_RCOC_REL_COMPL_IND:
case SCOC_E_RCOC_RLSD_IND:
/* release res + local ref (implicit) */
/* freeze local ref */
/* stop release + interval timers */
conn_stop_release_timers(conn);
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_RCOC_ROUT_FAIL_IND:
case SCOC_E_RCOC_OTHER_NPDU:
/* do nothing */
break;
case SCOC_E_T_REL_EXP: /* release timer exp */
/* send RLSD */
xua_gen_relre_and_send(conn, SCCP_RELEASE_CAUSE_UNQUALIFIED, NULL);
/* start interval timer */
conn_start_int_timer(conn);
/* start repeat release timer */
conn_start_rep_rel_timer(conn);
break;
case SCOC_E_T_INT_EXP: /* interval timer exp */
/* TODO: Inform maintenance */
/* stop release and interval timers */
conn_stop_release_timers(conn);
osmo_fsm_inst_state_chg(fi, S_IDLE, 0, 0);
break;
case SCOC_E_T_REP_REL_EXP: /* repeat release timer exp */
/* send RLSD */
xua_gen_relre_and_send(conn, SCCP_RELEASE_CAUSE_UNQUALIFIED, NULL);
/* re-start repeat release timer */
conn_start_rep_rel_timer(conn);
break;
}
}
static const struct osmo_fsm_state sccp_scoc_states[] = {
[S_IDLE] = {
.name = "IDLE",
.action = scoc_fsm_idle,
.onenter= scoc_fsm_idle_onenter,
.in_event_mask = S(SCOC_E_SCU_N_CONN_REQ) |
//S(SCOC_E_SCU_N_TYPE1_REQ) |
S(SCOC_E_RCOC_CONN_IND) |
S(SCOC_E_RCOC_RLSD_IND) |
S(SCOC_E_RCOC_REL_COMPL_IND) |
S(SCOC_E_RCOC_OTHER_NPDU),
.out_state_mask = S(S_CONN_PEND_OUT) |
S(S_CONN_PEND_IN),
},
[S_CONN_PEND_IN] = {
.name = "CONN_PEND_IN",
.action = scoc_fsm_conn_pend_in,
.in_event_mask = S(SCOC_E_SCU_N_CONN_RESP) |
S(SCOC_E_SCU_N_DISC_REQ),
.out_state_mask = S(S_IDLE) |
S(S_ACTIVE),
},
[S_CONN_PEND_OUT] = {
.name = "CONN_PEND_OUT",
.action = scoc_fsm_conn_pend_out,
.in_event_mask = S(SCOC_E_SCU_N_DISC_REQ) |
S(SCOC_E_CONN_TMR_EXP) |
S(SCOC_E_RCOC_ROUT_FAIL_IND) |
S(SCOC_E_RCOC_RLSD_IND) |
S(SCOC_E_RCOC_OTHER_NPDU) |
S(SCOC_E_RCOC_CREF_IND) |
S(SCOC_E_RCOC_CC_IND),
.out_state_mask = S(S_IDLE) |
S(S_ACTIVE) |
S(S_WAIT_CONN_CONF),
},
[S_ACTIVE] = {
.name = "ACTIVE",
.action = scoc_fsm_active,
.in_event_mask = S(SCOC_E_SCU_N_DISC_REQ) |
/* internal disconnect */
S(SCOC_E_RCOC_CREF_IND) |
S(SCOC_E_RCOC_REL_COMPL_IND) |
S(SCOC_E_RCOC_RLSD_IND) |
S(SCOC_E_RCOC_ERROR_IND) |
S(SCOC_E_T_IAR_EXP) |
S(SCOC_E_T_IAS_EXP) |
S(SCOC_E_RCOC_ROUT_FAIL_IND) |
S(SCOC_E_SCU_N_DATA_REQ) |
S(SCOC_E_SCU_N_EXP_DATA_REQ) |
S(SCOC_E_RCOC_DT1_IND) |
S(SCOC_E_RCOC_IT_IND),
.out_state_mask = S(S_IDLE) |
S(S_DISCONN_PEND),
},
[S_DISCONN_PEND] = {
.name = "DISCONN_PEND",
.action = scoc_fsm_disconn_pend,
.in_event_mask = S(SCOC_E_RCOC_REL_COMPL_IND) |
S(SCOC_E_RCOC_RLSD_IND) |
S(SCOC_E_RCOC_ROUT_FAIL_IND) |
S(SCOC_E_RCOC_OTHER_NPDU) |
S(SCOC_E_T_REL_EXP) |
S(SCOC_E_T_INT_EXP) |
S(SCOC_E_T_REP_REL_EXP),
.out_state_mask = S(S_IDLE),
},
[S_RESET_IN] = {
.name = "RESET_IN",
},
[S_RESET_OUT] = {
.name = "RESET_OUT",
},
[S_BOTHWAY_RESET] = {
.name = "BOTHWAY_RESET",
},
[S_WAIT_CONN_CONF] = {
.name = "WAIT_CONN_CONF",
.action = scoc_fsm_wait_conn_conf,
.in_event_mask = S(SCOC_E_RCOC_RLSD_IND) |
S(SCOC_E_RCOC_CC_IND) |
S(SCOC_E_RCOC_OTHER_NPDU) |
S(SCOC_E_CONN_TMR_EXP) |
S(SCOC_E_RCOC_CREF_IND) |
S(SCOC_E_RCOC_ROUT_FAIL_IND),
.out_state_mask = S(S_IDLE) |
S(S_DISCONN_PEND),
},
};
struct osmo_fsm sccp_scoc_fsm = {
.name = "SCCP-SCOC",
.states = sccp_scoc_states,
.num_states = ARRAY_SIZE(sccp_scoc_states),
/* ".log_subsys = DLSCCP" doesn't work as DLSCCP is not a constant */
.event_names = scoc_event_names,
};
/* map from SCCP return cause to SCCP Refusal cause */
static const uint8_t cause_map_cref[] = {
[SCCP_RETURN_CAUSE_SUBSYSTEM_CONGESTION] =
SCCP_REFUSAL_SUBSYTEM_CONGESTION,
[SCCP_RETURN_CAUSE_SUBSYSTEM_FAILURE] =
SCCP_REFUSAL_SUBSYSTEM_FAILURE,
[SCCP_RETURN_CAUSE_UNEQUIPPED_USER] =
SCCP_REFUSAL_UNEQUIPPED_USER,
[SCCP_RETURN_CAUSE_UNQUALIFIED] =
SCCP_REFUSAL_UNQUALIFIED,
[SCCP_RETURN_CAUSE_SCCP_FAILURE] =
SCCP_REFUSAL_SCCP_FAILURE,
[SCCP_RETURN_CAUSE_HOP_COUNTER_VIOLATION] =
SCCP_REFUSAL_HOP_COUNTER_VIOLATION,
};
static uint8_t get_cref_cause_for_ret(uint8_t ret_cause)
{
if (ret_cause < ARRAY_SIZE(cause_map_cref))
return cause_map_cref[ret_cause];
else
return SCCP_REFUSAL_UNQUALIFIED;
}
/* Generate a COREF message purely based on an incoming SUA message,
* without the use of any local connection state */
static struct xua_msg *gen_coref_without_conn(struct osmo_sccp_instance *inst,
struct xua_msg *xua_in,
uint32_t ref_cause)
{
struct xua_msg *xua;
xua = xua_msg_alloc();
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_COREF);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, inst->route_ctx);
xua_msg_copy_part(xua, SUA_IEI_DEST_REF, xua_in, SUA_IEI_SRC_REF);
xua_msg_add_u32(xua, SUA_IEI_CAUSE, SUA_CAUSE_T_REFUSAL | ref_cause);
/* optional: source addr */
xua_msg_copy_part(xua, SUA_IEI_SRC_ADDR, xua_in, SUA_IEI_DEST_ADDR);
/* conditional: dest addr */
xua_msg_copy_part(xua, SUA_IEI_DEST_ADDR, xua_in, SUA_IEI_SRC_ADDR);
/* optional: importance */
xua_msg_copy_part(xua, SUA_IEI_IMPORTANCE, xua_in, SUA_IEI_IMPORTANCE);
/* optional: data */
xua_msg_copy_part(xua, SUA_IEI_DATA, xua_in, SUA_IEI_DATA);
return xua;
}
/* Find a SCCP user for given SUA message (based on SUA_IEI_DEST_ADDR */
static struct osmo_sccp_user *sccp_find_user(struct osmo_sccp_instance *inst,
struct xua_msg *xua)
{
int rc;
struct osmo_sccp_addr called_addr;
rc = sua_addr_parse(&called_addr, xua, SUA_IEI_DEST_ADDR);
if (rc < 0) {
LOGP(DLSCCP, LOGL_ERROR, "Cannot find SCCP User for XUA "
"Message %s without valid DEST_ADDR\n",
xua_hdr_dump(xua, &xua_dialect_sua));
return NULL;
}
if (!(called_addr.presence & OSMO_SCCP_ADDR_T_SSN)) {
LOGP(DLSCCP, LOGL_ERROR, "Cannot resolve SCCP User for "
"XUA Message %s without SSN in CalledAddr\n",
xua_hdr_dump(xua, &xua_dialect_sua));
return NULL;
}
return sccp_user_find(inst, called_addr.ssn, called_addr.pc);
}
/*! \brief SCOC: Receive SCRC Routing Failure
* \param[in] inst SCCP Instance on which we operate
* \param[in] xua SUA message that was failed to route
* \param[in] return_cause Reason (cause) for routing failure */
void sccp_scoc_rx_scrc_rout_fail(struct osmo_sccp_instance *inst,
struct xua_msg *xua, uint32_t return_cause)
{
uint32_t conn_id;
struct sccp_connection *conn;
LOGP(DLSCCP, LOGL_NOTICE, "SCRC Routing Failure for message %s\n",
xua_hdr_dump(xua, &xua_dialect_sua));
/* try to dispatch to connection FSM (if any) */
conn_id = xua_msg_get_u32(xua, SUA_IEI_DEST_REF);
conn = conn_find_by_id(inst, conn_id);
if (conn) {
osmo_fsm_inst_dispatch(conn->fi,
SCOC_E_RCOC_ROUT_FAIL_IND, xua);
} else {
/* generate + send CREF directly */
struct xua_msg *cref;
uint8_t cref_cause = get_cref_cause_for_ret(return_cause);
cref = gen_coref_without_conn(inst, xua, cref_cause);
sccp_scrc_rx_scoc_conn_msg(inst, cref);
xua_msg_free(cref);
}
}
/* Generate a COERR based in input arguments */
static struct xua_msg *gen_coerr(uint32_t route_ctx, uint32_t dest_ref,
uint32_t err_cause)
{
struct xua_msg *xua = xua_msg_alloc();
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_COERR);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, route_ctx);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, dest_ref);
xua_msg_add_u32(xua, SUA_IEI_CAUSE, SUA_CAUSE_T_ERROR | err_cause);
return xua;
}
/* generate COERR from incoming XUA and send it */
static void tx_coerr_from_xua(struct osmo_sccp_instance *inst,
struct xua_msg *in, uint32_t err_cause)
{
struct xua_msg *xua;
uint32_t route_ctx, dest_ref;
route_ctx = xua_msg_get_u32(in, SUA_IEI_ROUTE_CTX);
/* get *source* reference and use as destination ref */
dest_ref = xua_msg_get_u32(in, SUA_IEI_SRC_REF);
xua = gen_coerr(route_ctx, dest_ref, err_cause);
/* copy over the MTP parameters */
xua->mtp.dpc = in->mtp.opc;
xua->mtp.opc = in->mtp.dpc;
xua->mtp.sio = in->mtp.sio;
/* sent to SCRC for transmission */
sccp_scrc_rx_scoc_conn_msg(inst, xua);
xua_msg_free(xua);
}
/* Generate a RELCO based in input arguments */
static struct xua_msg *gen_relco(uint32_t route_ctx, uint32_t dest_ref,
uint32_t src_ref)
{
struct xua_msg *xua = xua_msg_alloc();
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_RELCO);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, route_ctx);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, dest_ref);
xua_msg_add_u32(xua, SUA_IEI_SRC_REF, src_ref);
return xua;
}
/* generate RELCO from incoming XUA and send it */
static void tx_relco_from_xua(struct osmo_sccp_instance *inst,
struct xua_msg *in)
{
struct xua_msg *xua;
uint32_t route_ctx, dest_ref, src_ref;
route_ctx = xua_msg_get_u32(in, SUA_IEI_ROUTE_CTX);
/* get *source* reference and use as destination ref */
dest_ref = xua_msg_get_u32(in, SUA_IEI_SRC_REF);
/* get *dest* reference and use as source ref */
src_ref = xua_msg_get_u32(in, SUA_IEI_DEST_REF);
xua = gen_relco(route_ctx, dest_ref, src_ref);
/* copy over the MTP parameters */
xua->mtp.dpc = in->mtp.opc;
xua->mtp.opc = in->mtp.dpc;
xua->mtp.sio = in->mtp.sio;
/* send to SCRC for transmission */
sccp_scrc_rx_scoc_conn_msg(inst, xua);
xua_msg_free(xua);
}
/* Generate a RLSD based in input arguments */
static struct xua_msg *gen_rlsd(uint32_t route_ctx, uint32_t dest_ref,
uint32_t src_ref)
{
struct xua_msg *xua = xua_msg_alloc();
xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_RELRE);
xua_msg_add_u32(xua, SUA_IEI_ROUTE_CTX, route_ctx);
xua_msg_add_u32(xua, SUA_IEI_DEST_REF, dest_ref);
xua_msg_add_u32(xua, SUA_IEI_SRC_REF, src_ref);
return xua;
}
/* Generate a RLSD to both the remote side and the local conn */
static void tx_rlsd_from_xua_twoway(struct sccp_connection *conn,
struct xua_msg *in)
{
struct xua_msg *xua;
uint32_t route_ctx, dest_ref, src_ref;
route_ctx = xua_msg_get_u32(in, SUA_IEI_ROUTE_CTX);
/* get *source* reference and use as destination ref */
dest_ref = xua_msg_get_u32(in, SUA_IEI_SRC_REF);
/* get *source* reference and use as destination ref */
src_ref = xua_msg_get_u32(in, SUA_IEI_DEST_REF);
/* Generate RLSD towards remote peer */
xua = gen_rlsd(route_ctx, dest_ref, src_ref);
/* copy over the MTP parameters */
xua->mtp.dpc = in->mtp.opc;
xua->mtp.opc = in->mtp.dpc;
xua->mtp.sio = in->mtp.sio;
/* send to SCRC for transmission */
sccp_scrc_rx_scoc_conn_msg(conn->inst, xua);
xua_msg_free(xua);
/* Generate RLSD towards local peer */
xua = gen_rlsd(conn->inst->route_ctx, conn->conn_id, conn->remote_ref);
xua->mtp.dpc = in->mtp.dpc;
xua->mtp.opc = conn->remote_pc;
xua->mtp.sio = in->mtp.sio;
osmo_fsm_inst_dispatch(conn->fi, SCOC_E_RCOC_RLSD_IND, xua);
xua_msg_free(xua);
}
/* process received message for unassigned local reference */
static void sccp_scoc_rx_unass_local_ref(struct osmo_sccp_instance *inst,
struct xua_msg *xua)
{
/* we have received a message with unassigned destination local
* reference and thus apply the action indicated in Table
* B.2/Q.714 */
switch (xua->hdr.msg_type) {
case SUA_CO_COAK: /* CC */
case SUA_CO_COIT: /* IT */
case SUA_CO_RESRE: /* RSR */
case SUA_CO_RESCO: /* RSC */
/* Send COERR */
tx_coerr_from_xua(inst, xua, SCCP_ERROR_LRN_MISMATCH_UNASSIGNED);
break;
case SUA_CO_COREF: /* CREF */
case SUA_CO_RELCO: /* RLC */
case SUA_CO_CODT: /* DT1 */
case SUA_CO_CODA: /* AK */
case SUA_CO_COERR: /* ERR */
/* DISCARD */
break;
case SUA_CO_RELRE: /* RLSD */
/* Send RLC */
tx_relco_from_xua(inst, xua);
break;
default:
LOGP(DLSCCP, LOGL_NOTICE, "Unhandled %s\n",
xua_hdr_dump(xua, &xua_dialect_sua));
break;
}
}
/* process received message for invalid source local reference */
static void sccp_scoc_rx_inval_src_ref(struct sccp_connection *conn,
struct xua_msg *xua,
uint32_t inval_src_ref)
{
LOGP(DLSCCP, LOGL_NOTICE,
"Received message for source ref %u on conn with mismatching remote ref %u\n",
inval_src_ref, conn->remote_ref);
/* we have received a message with invalid source local
* reference and thus apply the action indicated in Table
* B.2/Q.714 */
switch (xua->hdr.msg_type) {
case SUA_CO_RELRE: /* RLSD */
case SUA_CO_RESRE: /* RSR */
case SUA_CO_RESCO: /* RSC */
/* Send ERR */
tx_coerr_from_xua(conn->inst, xua, SCCP_ERROR_LRN_MISMATCH_INCONSISTENT);
break;
case SUA_CO_COIT: /* IT */
/* FIXME: RLSD to both sides */
tx_rlsd_from_xua_twoway(conn, xua);
break;
case SUA_CO_RELCO: /* RLC */
/* DISCARD */
break;
default:
LOGP(DLSCCP, LOGL_NOTICE, "Unhandled %s\n",
xua_hdr_dump(xua, &xua_dialect_sua));
break;
}
}
/* process received message for invalid origin point code */
static void sccp_scoc_rx_inval_opc(struct sccp_connection *conn,
struct xua_msg *xua)
{
LOGP(DLSCCP, LOGL_NOTICE,
"Received message %s for opc=%u=%s on conn with mismatching remote pc=%u=%s\n",
xua_hdr_dump(xua, &xua_dialect_sua),
xua->mtp.opc, osmo_ss7_pointcode_print(conn->inst->ss7, xua->mtp.opc),
conn->remote_pc, osmo_ss7_pointcode_print2(conn->inst->ss7, conn->remote_pc));
/* we have received a message with invalid origin PC and thus
* apply the action indicated in Table B.2/Q.714 */
switch (xua->hdr.msg_type) {
case SUA_CO_RELRE: /* RLSD */
case SUA_CO_RESRE: /* RSR */
case SUA_CO_RESCO: /* RSC */
/* Send ERR */
tx_coerr_from_xua(conn->inst, xua, SCCP_ERROR_POINT_CODE_MISMATCH);
break;
case SUA_CO_RELCO: /* RLC */
case SUA_CO_CODT: /* DT1 */
case SUA_CO_CODA: /* AK */
case SUA_CO_COERR: /* ERR */
/* DISCARD */
break;
default:
LOGP(DLSCCP, LOGL_NOTICE, "Unhandled %s\n",
xua_hdr_dump(xua, &xua_dialect_sua));
break;
}
}
/*! \brief Main entrance function for primitives from the SCRC (Routing Control)
* \param[in] inst SCCP Instance in which we operate
* \param[in] xua SUA message in xua_msg format */
void sccp_scoc_rx_from_scrc(struct osmo_sccp_instance *inst,
struct xua_msg *xua)
{
struct sccp_connection *conn;
struct osmo_sccp_user *scu;
uint32_t src_loc_ref;
int event;
/* we basically try to convert the SUA message into an event,
* and then dispatch the event to the connection-specific FSM.
* If it is a CORE (Connect REquest), we create the connection
* (and implicitly its FSM) first */
if (xua->hdr.msg_type == SUA_CO_CORE) {
scu = sccp_find_user(inst, xua);
if (!scu) {
/* this shouldn't happen, as the caller should
* have already verified that a local user is
* equipped for this SSN */
LOGP(DLSCCP, LOGL_ERROR, "Cannot find user for "
"CORE ?!?\n");
return;
}
/* Allocate new connection */
conn = conn_create(scu);
conn->incoming = true;
} else {
uint32_t conn_id;
/* Resolve existing connection */
conn_id = xua_msg_get_u32(xua, SUA_IEI_DEST_REF);
conn = conn_find_by_id(inst, conn_id);
if (!conn) {
LOGP(DLSCCP, LOGL_NOTICE, "Received %s: Cannot find connection for "
"local reference %u\n", xua_hdr_dump(xua, &xua_dialect_sua), conn_id);
sccp_scoc_rx_unass_local_ref(inst, xua);
return;
}
}
OSMO_ASSERT(conn);
OSMO_ASSERT(conn->fi);
DEBUGP(DLSCCP, "Received %s for local reference %u\n",
xua_hdr_dump(xua, &xua_dialect_sua), conn->conn_id);
if (xua->hdr.msg_type != SUA_CO_CORE &&
xua->hdr.msg_type != SUA_CO_COAK &&
xua->hdr.msg_type != SUA_CO_COREF) {
if (xua_msg_find_tag(xua, SUA_IEI_SRC_REF)) {
/* Check if received source local reference !=
* the one we saved in local state */
src_loc_ref = xua_msg_get_u32(xua, SUA_IEI_SRC_REF);
if (src_loc_ref != conn->remote_ref) {
sccp_scoc_rx_inval_src_ref(conn, xua, src_loc_ref);
return;
}
}
/* Check if received OPC != the remote_pc we stored locally */
if (xua->mtp.opc != conn->remote_pc) {
sccp_scoc_rx_inval_opc(conn, xua);
return;
}
}
/* Map from XUA message to event */
event = xua_msg_event_map(xua, sua_scoc_event_map, ARRAY_SIZE(sua_scoc_event_map));
if (event < 0) {
LOGP(DLSCCP, LOGL_ERROR, "Cannot map SCRC msg %s to event\n",
xua_hdr_dump(xua, &xua_dialect_sua));
/* Table B.1/Q714 states DISCARD for any message with
* unknown type */
return;
}
/* Dispatch event to existing connection */
osmo_fsm_inst_dispatch(conn->fi, event, xua);
}
/* get the Connection ID of the given SCU primitive */
static uint32_t scu_prim_conn_id(const struct osmo_scu_prim *prim)
{
switch (prim->oph.primitive) {
case OSMO_SCU_PRIM_N_CONNECT:
return prim->u.connect.conn_id;
case OSMO_SCU_PRIM_N_DATA:
return prim->u.data.conn_id;
case OSMO_SCU_PRIM_N_DISCONNECT:
return prim->u.disconnect.conn_id;
case OSMO_SCU_PRIM_N_RESET:
return prim->u.reset.conn_id;
default:
return 0;
}
}
/*! Main entrance function for primitives from SCCP User.
* The caller is required to free oph->msg, otherwise the same as osmo_sccp_user_sap_down().
* \param[in] scu SCCP User sending us the primitive
* \param[in] oph Osmocom primitive sent by the user
* \returns 0 on success; negative on error */
int osmo_sccp_user_sap_down_nofree(struct osmo_sccp_user *scu, struct osmo_prim_hdr *oph)
{
struct osmo_scu_prim *prim = (struct osmo_scu_prim *) oph;
struct osmo_sccp_instance *inst = scu->inst;
struct sccp_connection *conn;
int rc = 0;
int event;
LOGP(DLSCCP, LOGL_DEBUG, "Received SCCP User Primitive (%s)\n",
osmo_scu_prim_name(&prim->oph));
switch (OSMO_PRIM_HDR(&prim->oph)) {
case OSMO_PRIM(OSMO_SCU_PRIM_N_UNITDATA, PRIM_OP_REQUEST):
/* other CL primitives? */
/* Connectionless by-passes this altogether */
return sccp_sclc_user_sap_down_nofree(scu, oph);
case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_REQUEST):
/* Allocate new connection structure */
conn = conn_create_id(scu, prim->u.connect.conn_id);
if (!conn) {
/* FIXME: inform SCCP user with proper reply */
LOGP(DLSCCP, LOGL_ERROR, "Cannot create conn-id for primitive %s\n",
osmo_scu_prim_name(&prim->oph));
return rc;
}
break;
case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_RESPONSE):
case OSMO_PRIM(OSMO_SCU_PRIM_N_DATA, PRIM_OP_REQUEST):
case OSMO_PRIM(OSMO_SCU_PRIM_N_DISCONNECT, PRIM_OP_REQUEST):
case OSMO_PRIM(OSMO_SCU_PRIM_N_RESET, PRIM_OP_REQUEST):
/* Resolve existing connection structure */
conn = conn_find_by_id(inst, scu_prim_conn_id(prim));
if (!conn) {
/* FIXME: inform SCCP user with proper reply */
LOGP(DLSCCP, LOGL_ERROR, "Received unknown conn-id %u for primitive %s\n",
scu_prim_conn_id(prim), osmo_scu_prim_name(&prim->oph));
return rc;
}
break;
default:
LOGP(DLSCCP, LOGL_ERROR, "Received unknown primitive %s\n",
osmo_scu_prim_name(&prim->oph));
return -1;
}
/* Map from primitive to event */
event = osmo_event_for_prim(oph, scu_scoc_event_map);
/* Dispatch event into connection */
return osmo_fsm_inst_dispatch(conn->fi, event, prim);
}
/*! Main entrance function for primitives from SCCP User.
* Implies a msgb_free(oph->msg), otherwise the same as osmo_sccp_user_sap().
* \param[in] scu SCCP User sending us the primitive
* \param[in] oph Osmocom primitive sent by the user
* \returns 0 on success; negative on error */
int osmo_sccp_user_sap_down(struct osmo_sccp_user *scu, struct osmo_prim_hdr *oph)
{
struct osmo_scu_prim *prim = (struct osmo_scu_prim *) oph;
struct msgb *msg = prim->oph.msg;
int rc = osmo_sccp_user_sap_down_nofree(scu, oph);
msgb_free(msg);
return rc;
}
void sccp_scoc_flush_connections(struct osmo_sccp_instance *inst)
{
struct rb_node *node;
while ((node = rb_first(&inst->connections))) {
struct sccp_connection *conn = container_of(node, struct sccp_connection, node);
conn_destroy(conn);
}
}
#include <osmocom/vty/vty.h>
static void vty_show_connection(struct vty *vty, struct sccp_connection *conn)
{
struct osmo_ss7_instance *s7i = conn->inst->ss7;
struct osmo_sccp_addr *remote_addr;
uint32_t local_pc = OSMO_SS7_PC_INVALID;
if (osmo_ss7_pc_is_valid(conn->user->pc))
local_pc = conn->user->pc;
else if (osmo_ss7_pc_is_valid(s7i->cfg.primary_pc))
local_pc = s7i->cfg.primary_pc;
if (conn->incoming)
remote_addr = &conn->calling_addr;
else
remote_addr = &conn->called_addr;
vty_out(vty, "%c %06x %3u %7s ", conn->incoming ? 'I' : 'O',
conn->conn_id, conn->user->ssn,
osmo_ss7_pointcode_print(s7i, local_pc));
vty_out(vty, "%16s %06x %3u %7s%s",
osmo_fsm_inst_state_name(conn->fi), conn->remote_ref, remote_addr->ssn,
osmo_ss7_pointcode_print(s7i, conn->remote_pc),
VTY_NEWLINE);
}
void sccp_scoc_show_connections(struct vty *vty, struct osmo_sccp_instance *inst)
{
struct sccp_connection *conn;
struct rb_node *node;
vty_out(vty, "I Local Conn. Remote %s", VTY_NEWLINE);
vty_out(vty, "O Ref SSN PC State Ref SSN PC %s", VTY_NEWLINE);
vty_out(vty, "- ------ --- ------- ---------------- ------ --- -------%s", VTY_NEWLINE);
for (node = rb_first(&inst->connections); node; node = rb_next(node)) {
conn = container_of(node, struct sccp_connection, node);
vty_show_connection(vty, conn);
}
}
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