pespin has submitted this change. ( https://gerrit.osmocom.org/c/libosmo-sigtran/+/39689?usp=email ) ( 1 is the latest approved patch-set. No files were changed between the latest approved patch-set and the submitted one. )Change subject: sccp: Apply SLS on locally-originated transmitted Connection-Oriented messages ...................................................................... sccp: Apply SLS on locally-originated transmitted Connection-Oriented messages Change-Id: I1956acf631867b12b647d14c10057ded20d7fa2f --- M src/sccp_scoc.c 1 file changed, 34 insertions(+), 3 deletions(-) Approvals: pespin: Looks good to me, approved osmith: Looks good to me, but someone else must approve Jenkins Builder: Verified laforge: Looks good to me, but someone else must approve diff --git a/src/sccp_scoc.c b/src/sccp_scoc.c index c11dddf..8222bde 100644 --- a/src/sccp_scoc.c +++ b/src/sccp_scoc.c @@ -102,6 +102,11 @@ uint32_t sccp_class; uint32_t release_cause; /* WAIT_CONN_CONF */ + /* SLS to be used to transmit all Connection-oriented messages + * (ITU-T Q.714 1.1.2.3 Protocol class 2). + * SLS is 4 bits, as described in ITU Q.704 Figure 3 */ + uint8_t tx_co_mtp_sls; + struct msgb *opt_data_cache; /* incoming (true) or outgoing (false) */ @@ -450,6 +455,26 @@ #define INIT_TIMER(x, fn, priv) do { (x)->cb = fn; (x)->data = priv; } while (0) +/* Generate an SLS to be used for Connection-oriented messages on this SCCP connection. + * SLS is 4 bits, as described in ITU Q.704 Figure 3. + * ITU-T Q.714 1.1.2.3 Protocol class 2: + * "Messages belonging to a given signalling connection shall contain the same + * value of the SLS field to ensure sequencing as described in 1.1.2.2" + */ +static uint8_t sccp_conn_gen_tx_co_mtp_sls(const struct sccp_connection *conn) +{ + /* Implementation: Derive the SLS from conn->conn_id. */ + const uint32_t id = conn->conn_id; + uint8_t sls; + + /* First shrink it to 1 byte: */ + sls = ((id >> (3*8)) ^ (id >> (2*8)) ^ (id >> (1*8)) ^ (id)) & 0xff; + /* Now shrink it 8 -> 4 bits: */ + sls = ((sls >> 4) ^ sls) & 0x0f; + + return sls; +} + /* allocate + init a SCCP Connection with given ID */ static struct sccp_connection *conn_create_id(struct osmo_sccp_user *user, uint32_t conn_id) { @@ -472,6 +497,8 @@ INIT_TIMER(&conn->t_int, int_tmr_cb, conn); INIT_TIMER(&conn->t_rep_rel, rep_rel_tmr_cb, conn); + conn->tx_co_mtp_sls = sccp_conn_gen_tx_co_mtp_sls(conn); + /* this might change at runtime, as it is not a constant :/ */ sccp_scoc_fsm.log_subsys = DLSCCP; @@ -715,6 +742,13 @@ if (!xua) return NULL; + /* amend this with point code information; Many CO msgs + * includes neither called nor calling party address! */ + xua->mtp.dpc = conn->remote_pc; + + /* Apply SLS calculated for the connection (ITU-T Q.714 1.1.2.3). */ + xua->mtp.sls = conn->tx_co_mtp_sls; + switch (msg_type) { case SUA_CO_CORE: /* Connect Request == SCCP CR */ xua->hdr = XUA_HDR(SUA_MSGC_CO, SUA_CO_CORE); @@ -835,9 +869,6 @@ 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; -- To view, visit https://gerrit.osmocom.org/c/libosmo-sigtran/+/39689?usp=email To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings?usp=email Gerrit-MessageType: merged Gerrit-Project: libosmo-sigtran Gerrit-Branch: master Gerrit-Change-Id: I1956acf631867b12b647d14c10057ded20d7fa2f Gerrit-Change-Number: 39689 Gerrit-PatchSet: 2 Gerrit-Owner: pespin <pespin@sysmocom.de> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: laforge <laforge@osmocom.org> Gerrit-Reviewer: osmith <osmith@sysmocom.de> Gerrit-Reviewer: pespin <pespin@sysmocom.de>