neels has uploaded this change for review. ( https://gerrit.osmocom.org/c/libosmo-sccp/+/32361 ) Change subject: SCCP: implement variable limit on Optional Data (CR,CC,CREF,RLSD) ...................................................................... SCCP: implement variable limit on Optional Data (CR,CC,CREF,RLSD) When the Optional Data surpasses 130 bytes, it is not sent as part of SCCP CR, CC, CREF or RLSD messages, but gets sent separately in a Data Form 1. Make this 130 user configurable. This is specified to be 130 bytes exactly, but to interop with non-conforming peers, make this limit adjustable per cs7 instance, via osmo_sccp_vty_init(). Add and test new VTY config: cs7 instance N sccp max-optional-data (<0-999999>|standard) Related: ITU-T Q.713 4.2 to 4.5 Related: Ia68dad973ef18513b52f5accb5264c557c7295ea osmo-ttcn3-hacks Related: SYS#6423 Change-Id: If35697234796af8943691b2de62218e7dc93a08c --- M src/sccp_internal.h M src/sccp_scoc.c M src/sccp_user.c M src/sccp_vty.c M tests/vty/ss7_asp_test.vty 5 files changed, 111 insertions(+), 3 deletions(-) git pull ssh://gerrit.osmocom.org:29418/libosmo-sccp refs/changes/61/32361/1 diff --git a/src/sccp_internal.h b/src/sccp_internal.h index bfdca34..3027ae6 100644 --- a/src/sccp_internal.h +++ b/src/sccp_internal.h @@ -58,6 +58,8 @@ struct osmo_ss7_user ss7_user; struct osmo_sccp_timer_val timers[OSMO_SCCP_TIMERS_COUNT]; + + uint32_t max_optional_data; }; struct osmo_sccp_user { diff --git a/src/sccp_scoc.c b/src/sccp_scoc.c index c929ed6..1838615 100644 --- a/src/sccp_scoc.c +++ b/src/sccp_scoc.c @@ -676,11 +676,12 @@ 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) > SCCP_MAX_OPTIONAL_DATA) { + 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", @@ -703,6 +704,8 @@ /* 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; @@ -711,7 +714,7 @@ 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, SCCP_MAX_OPTIONAL_DATA, "over ITU-T Rec. Q.713 §4.4 limit")) { + 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) */ @@ -719,7 +722,7 @@ } break; case SUA_CO_RELRE: /* §4.5 Released (RLSD) */ - if (msgb_l2len(prim->oph.msg) > SCCP_MAX_OPTIONAL_DATA) { + 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: diff --git a/src/sccp_user.c b/src/sccp_user.c index e619c90..34c663d 100644 --- a/src/sccp_user.c +++ b/src/sccp_user.c @@ -35,6 +35,7 @@ #include <osmocom/sigtran/mtp_sap.h> #include <osmocom/sigtran/protocol/mtp.h> #include <osmocom/sigtran/sccp_helpers.h> +#include <osmocom/sccp/sccp_types.h> #include "sccp_internal.h" #include "xua_internal.h" @@ -235,6 +236,7 @@ inst->ss7_user.name = "SCCP"; inst->ss7_user.prim_cb = mtp_user_prim_cb; inst->ss7_user.priv = inst; + inst->max_optional_data = SCCP_MAX_OPTIONAL_DATA; rc = sccp_scmg_init(inst); if (rc < 0) { diff --git a/src/sccp_vty.c b/src/sccp_vty.c index 13fe402..1aa3e51 100644 --- a/src/sccp_vty.c +++ b/src/sccp_vty.c @@ -37,6 +37,8 @@ #include <osmocom/sigtran/osmo_ss7.h> #include <osmocom/sigtran/protocol/mtp.h> +#include <osmocom/sccp/sccp_types.h> + #include "xua_internal.h" #include "sccp_internal.h" @@ -165,6 +167,35 @@ return CMD_SUCCESS; } +DEFUN_ATTR(sccp_max_optional_data, sccp_max_optional_data_cmd, + "sccp max-optional-data (<0-999999>|standard)", + "Configure SCCP behavior\n" + "Set an upper bound for the optional data length (the payload) for CR, CC, CREF and RLSD messages." + " RANAP payload larger than this value (octets), send an SCCP CR without data, followed by an SCCP DT." + " ITU-T Q.713 4.2 to 4.5 define a limit of 130 bytes for the 'Data' parameter. This limit can be" + " adjusted here. May be useful for interop with nonstandard peers.\n" + "Set a non-standard maxium allowed number of bytes\n" + "Use the ITU-T Q.713 4.2 to 4.5 standard value of 130\n", + CMD_ATTR_IMMEDIATE) +{ + struct osmo_ss7_instance *ss7 = vty->index; + int val; + + if (!strcmp(argv[0], "standard")) + val = SCCP_MAX_OPTIONAL_DATA; + else + val = atoi(argv[0]); + + osmo_ss7_ensure_sccp(ss7); + if (!ss7->sccp) { + vty_out(vty, "%% Error: cannot instantiate SCCP instance%s", VTY_NEWLINE); + return CMD_WARNING; + } + + ss7->sccp->max_optional_data = val; + return CMD_SUCCESS; +} + static const char *osmo_sccp_timer_val_name(const struct osmo_sccp_timer_val *val) { static char buf[16]; @@ -227,6 +258,8 @@ void osmo_sccp_vty_write_cs7_node(struct vty *vty, const char *indent, struct osmo_sccp_instance *inst) { write_sccp_timers(vty, indent, inst, false); + if (inst->max_optional_data != SCCP_MAX_OPTIONAL_DATA) + vty_out(vty, "%ssccp max-optional-data %u%s", indent, inst->max_optional_data, VTY_NEWLINE); } DEFUN(show_sccp_timers, show_sccp_timers_cmd, @@ -262,4 +295,5 @@ install_lib_element_ve(&show_sccp_timers_cmd); gen_sccp_timer_cmd_strs(&sccp_timer_cmd); install_lib_element(L_CS7_NODE, &sccp_timer_cmd); + install_lib_element(L_CS7_NODE, &sccp_max_optional_data_cmd); } diff --git a/tests/vty/ss7_asp_test.vty b/tests/vty/ss7_asp_test.vty index 09be45b..4922f82 100644 --- a/tests/vty/ss7_asp_test.vty +++ b/tests/vty/ss7_asp_test.vty @@ -89,6 +89,7 @@ sccp-address NAME no sccp-address NAME sccp-timer (conn_est|ias|iar|rel|repeat_rel|int|guard|reset|reassembly) <1-999999> + sccp max-optional-data (<0-999999>|standard) ss7_asp_vty_test(config-cs7)# ? ... @@ -101,6 +102,7 @@ as Configure an Application Server sccp-address Create/Modify an SCCP addressbook entry sccp-timer Configure SCCP timer values, see ITU-T Q.714 + sccp Configure SCCP behavior ss7_asp_vty_test(config-cs7)# description ? TEXT Text until the end of the line @@ -427,3 +429,43 @@ ss7_asp_vty_test(config-cs7)# sccp-timer conn_est ? <1-999999> Timer value, in seconds + +ss7_asp_vty_test(config-cs7)# sccp ? + max-optional-data Set an upper bound for the optional data length (the payload) for CR, CC, CREF and RLSD messages. RANAP payload larger than this value (octets), send an SCCP CR without data, followed by an SCCP DT. ITU-T Q.713 4.2 to 4.5 define a limit of 130 bytes for the 'Data' parameter. This limit can be adjusted here. May be useful for interop with nonstandard peers. + +ss7_asp_vty_test(config-cs7)# sccp max-optional-data ? + <0-999999> Set a non-standard maxium allowed number of bytes + standard Use the ITU-T Q.713 4.2 to 4.5 standard value of 130 + +ss7_asp_vty_test(config-cs7)# show running-config +... !sccp max-optional-data + +ss7_asp_vty_test(config-cs7)# sccp max-optional-data 0 +ss7_asp_vty_test(config-cs7)# show running-config +... + sccp max-optional-data 0 +... + +ss7_asp_vty_test(config-cs7)# sccp max-optional-data 123 +ss7_asp_vty_test(config-cs7)# show running-config +... + sccp max-optional-data 123 +... + +ss7_asp_vty_test(config-cs7)# sccp max-optional-data 999999 +ss7_asp_vty_test(config-cs7)# show running-config +... +cs7 instance 0 +... + sccp max-optional-data 999999 +... +cs7 instance 1 +... !sccp max-optional-data + +ss7_asp_vty_test(config-cs7)# sccp max-optional-data standard +ss7_asp_vty_test(config-cs7)# show running-config +... !sccp max-optional-data + +ss7_asp_vty_test(config-cs7)# sccp max-optional-data 130 +ss7_asp_vty_test(config-cs7)# show running-config +... !sccp max-optional-data -- To view, visit https://gerrit.osmocom.org/c/libosmo-sccp/+/32361 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: libosmo-sccp Gerrit-Branch: master Gerrit-Change-Id: If35697234796af8943691b2de62218e7dc93a08c Gerrit-Change-Number: 32361 Gerrit-PatchSet: 1 Gerrit-Owner: neels <nhofmeyr@sysmocom.de> Gerrit-MessageType: newchange