pespin has uploaded this change for review. ( https://gerrit.osmocom.org/c/libosmo-sccp/+/30284 ) Change subject: sccp: Validate local references > 0x00fffffe are not used ...................................................................... sccp: Validate local references > 0x00fffffe are not used SUA allows references of 4 bytes, but SCCP/M3UA doesn't. SUA: RFC3868 sec 3.10.4: The source reference number is a 4 octet long integer. This isallocated 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. Related: SYS#6211 Change-Id: Ia547346bdae54a032d2198ecd4972fb3f8dd073e --- M src/sccp2sua.c 1 file changed, 52 insertions(+), 14 deletions(-) git pull ssh://gerrit.osmocom.org:29418/libosmo-sccp refs/changes/84/30284/1 diff --git a/src/sccp2sua.c b/src/sccp2sua.c index 51fe00b..f18ebd7 100644 --- a/src/sccp2sua.c +++ b/src/sccp2sua.c @@ -26,6 +26,7 @@ #include <stdbool.h> #include <string.h> #include <errno.h> +#include <inttypes.h> #include <osmocom/sccp/sccp.h> #include <osmocom/core/linuxlist.h> @@ -1002,13 +1003,18 @@ return 0; } -/* store a 'local reference' as big-eidian 24bit value at local_ref */ -static void store_local_ref(struct sccp_source_reference *local_ref, struct xua_msg *xua, uint16_t iei) +/* store a 'local reference' as big-endian 24bit value at local_ref */ +static int store_local_ref(struct sccp_source_reference *local_ref, struct xua_msg *xua, uint16_t iei) { uint32_t tmp32 = xua_msg_get_u32(xua, iei); + if (tmp32 > 0x00fffffe) { + LOGP(DLSUA, LOGL_ERROR, "SUA->SCCP: Local Reference value 0x%" PRIx32 " > 0x00fffffe\n", tmp32); + return -1; + } local_ref->octet1 = (tmp32 >> 16) & 0xff; local_ref->octet2 = (tmp32 >> 8) & 0xff; local_ref->octet3 = tmp32 & 0xff; + return 0; } /*! \returns \ref xua in case of success, NULL on error (xua not freed!) */ @@ -1031,12 +1037,15 @@ static int sua_to_sccp_cr(struct msgb *msg, struct xua_msg *xua) { struct sccp_connection_request *req; + int rc; req = (struct sccp_connection_request *) msgb_put(msg, sizeof(*req)); /* Fixed Part */ req->type = SCCP_MSG_TYPE_CR; req->proto_class = xua_msg_get_u32(xua, SUA_IEI_PROTO_CLASS); - store_local_ref(&req->source_local_reference, xua, SUA_IEI_SRC_REF); + rc = store_local_ref(&req->source_local_reference, xua, SUA_IEI_SRC_REF); + if (rc < 0) + return rc; /* Variable Part */ sccp_add_var_addr(msg, &req->variable_called, xua, SUA_IEI_DEST_ADDR); @@ -1061,13 +1070,18 @@ static int sua_to_sccp_cc(struct msgb *msg, struct xua_msg *xua) { struct sccp_connection_confirm *cnf; + int rc; cnf = (struct sccp_connection_confirm *) msgb_put(msg, sizeof(*cnf)); /* Fixed Part */ cnf->type = SCCP_MSG_TYPE_CC; cnf->proto_class = xua_msg_get_u32(xua, SUA_IEI_PROTO_CLASS); - store_local_ref(&cnf->destination_local_reference, xua, SUA_IEI_DEST_REF); - store_local_ref(&cnf->source_local_reference, xua, SUA_IEI_SRC_REF); + rc = store_local_ref(&cnf->destination_local_reference, xua, SUA_IEI_DEST_REF); + if (rc < 0) + return rc; + rc = store_local_ref(&cnf->source_local_reference, xua, SUA_IEI_SRC_REF); + if (rc < 0) + return rc; /* Optional Part */ return xua_ies_to_sccp_opts(msg, &cnf->optional_start, cnf->type, xua); } @@ -1088,11 +1102,14 @@ static int sua_to_sccp_cref(struct msgb *msg, struct xua_msg *xua) { struct sccp_connection_refused *ref; + int rc; ref = (struct sccp_connection_refused *) msgb_put(msg, sizeof(*ref)); /* Fixed Part */ ref->type = SCCP_MSG_TYPE_CREF; - store_local_ref(&ref->destination_local_reference, xua, SUA_IEI_DEST_REF); + rc = store_local_ref(&ref->destination_local_reference, xua, SUA_IEI_DEST_REF); + if (rc < 0) + return rc; ref->cause = xua_msg_get_u32(xua, SUA_IEI_CAUSE) & 0xff; /* Optional Part */ return xua_ies_to_sccp_opts(msg, &ref->optional_start, ref->type, xua); @@ -1114,12 +1131,17 @@ static int sua_to_sccp_rlsd(struct msgb *msg, struct xua_msg *xua) { struct sccp_connection_released *rlsd; + int rc; rlsd =(struct sccp_connection_released *) msgb_put(msg, sizeof(*rlsd)); /* Fixed Part */ rlsd->type = SCCP_MSG_TYPE_RLSD; - store_local_ref(&rlsd->destination_local_reference, xua, SUA_IEI_DEST_REF); - store_local_ref(&rlsd->source_local_reference, xua, SUA_IEI_SRC_REF); + rc = store_local_ref(&rlsd->destination_local_reference, xua, SUA_IEI_DEST_REF); + if (rc < 0) + return rc; + rc = store_local_ref(&rlsd->source_local_reference, xua, SUA_IEI_SRC_REF); + if (rc < 0) + return rc; rlsd->release_cause = xua_msg_get_u32(xua, SUA_IEI_CAUSE) & 0xff; /* Optional Part */ @@ -1141,12 +1163,17 @@ static int sua_to_sccp_rlc(struct msgb *msg, struct xua_msg *xua) { struct sccp_connection_release_complete *rlc; + int rc; rlc = (struct sccp_connection_release_complete *) msgb_put(msg, sizeof(*rlc)); /* Fixed Part */ rlc->type = SCCP_MSG_TYPE_RLC; - store_local_ref(&rlc->destination_local_reference, xua, SUA_IEI_DEST_REF); - store_local_ref(&rlc->source_local_reference, xua, SUA_IEI_SRC_REF); + rc = store_local_ref(&rlc->destination_local_reference, xua, SUA_IEI_DEST_REF); + if (rc < 0) + return rc; + rc = store_local_ref(&rlc->source_local_reference, xua, SUA_IEI_SRC_REF); + if (rc < 0) + return rc; return 0; } @@ -1168,11 +1195,14 @@ static int sua_to_sccp_dt1(struct msgb *msg, struct xua_msg *xua) { struct sccp_data_form1 *dt1; + int rc; dt1 = (struct sccp_data_form1 *) msgb_put(msg, sizeof(*dt1)); /* Fixed Part */ dt1->type = SCCP_MSG_TYPE_DT1; - store_local_ref(&dt1->destination_local_reference, xua, SUA_IEI_DEST_REF); + rc = store_local_ref(&dt1->destination_local_reference, xua, SUA_IEI_DEST_REF); + if (rc < 0) + return rc; dt1->segmenting = xua_msg_get_u32(xua, SUA_IEI_SEGMENTATION); /* Variable Part */ sccp_add_variable_part(msg, &dt1->variable_start, xua, SUA_IEI_DATA); @@ -1365,13 +1395,18 @@ static int sua_to_sccp_it(struct msgb *msg, struct xua_msg *xua) { struct sccp_data_it *it; + int rc; it = (struct sccp_data_it *) msgb_put(msg, sizeof(*it)); /* Fixed Part */ it->type = SCCP_MSG_TYPE_IT; it->proto_class = xua_msg_get_u32(xua, SUA_IEI_PROTO_CLASS); - store_local_ref(&it->destination_local_reference, xua, SUA_IEI_DEST_REF); - store_local_ref(&it->source_local_reference, xua, SUA_IEI_SRC_REF); + rc = store_local_ref(&it->destination_local_reference, xua, SUA_IEI_DEST_REF); + if (rc < 0) + return rc; + rc = store_local_ref(&it->source_local_reference, xua, SUA_IEI_SRC_REF); + if (rc < 0) + return rc; if ((it->proto_class & 0xF) == 3) { //it->sequencing it->credit = xua_msg_get_u32(xua, SUA_IEI_CREDIT); @@ -1394,11 +1429,14 @@ static int sua_to_sccp_err(struct msgb *msg, struct xua_msg *xua) { struct sccp_proto_err *err; + int rc; err = (struct sccp_proto_err *) msgb_put(msg, sizeof(*err)); /* Fixed Part */ err->type = SCCP_MSG_TYPE_ERR; - store_local_ref(&err->destination_local_reference, xua, SUA_IEI_DEST_REF); + rc = store_local_ref(&err->destination_local_reference, xua, SUA_IEI_DEST_REF); + if (rc < 0) + return rc; err->error_cause = xua_msg_get_u32(xua, SUA_IEI_CAUSE) & 0xff; return 0; } -- To view, visit https://gerrit.osmocom.org/c/libosmo-sccp/+/30284 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: libosmo-sccp Gerrit-Branch: master Gerrit-Change-Id: Ia547346bdae54a032d2198ecd4972fb3f8dd073e Gerrit-Change-Number: 30284 Gerrit-PatchSet: 1 Gerrit-Owner: pespin <pespin@sysmocom.de> Gerrit-MessageType: newchange