lynxis lazus has submitted this change. ( https://gerrit.osmocom.org/c/osmo-sgsn/+/40975?usp=email )
(
3 is the latest approved patch-set. No files were changed between the latest approved patch-set and the submitted one. )Change subject: ranap: Improve error handling in Rx RESET ......................................................................
ranap: Improve error handling in Rx RESET
* Verify the CN Indicator is set to PS to avoid reacting on content from unexpected peers (eg. IuCS). If none is set, be permissive on rx and assume PS.
* If GlobalRNC-ID IE is missing, reject the RESET with an Error Indication towards the peer to notify about the rejection. Same if we couldn't decode properly it.
* Introduce Tx helpers for generic SCCP UNITDATA.req and RANAP Error Indication helpers to simplify code and avoid duplication.
Depends: osmo-iuh.git Change-Id I58c75b3e0e0f33f48d077385ffac820a6b2be59e Change-Id: I2a53e10c3903992a42d081e3ec300fbdb9b3c34c --- M TODO-RELEASE M include/osmocom/sgsn/gprs_ranap.h M src/sgsn/gprs_ranap.c 3 files changed, 68 insertions(+), 5 deletions(-)
Approvals: lynxis lazus: Looks good to me, approved Jenkins Builder: Verified
diff --git a/TODO-RELEASE b/TODO-RELEASE index 1dfbdb0..09e8951 100644 --- a/TODO-RELEASE +++ b/TODO-RELEASE @@ -12,3 +12,4 @@ libosmocore >1.10.0 enum gsm48_gprs_ie_mm: GSM48_IE_GMM_UE_NET_CAP, GSM48_IE_GMM_VD_PREF_UE_USAGE libosmo-gsup-client >1.8.0 osmo_gsup_client_is_connected(), osmo_gsup_client_get_rem_addr(), osmo_gsup_client_get_rem_port() osmo-iuh >1.7.0 ranap multiple params are constified, see osmo-iuh Change-Id I667dc2ef377c1ceb5b11315458f00b282c143c81 +osmo-iuh >1.7.0 ranap_new_msg_error_ind() \ No newline at end of file diff --git a/include/osmocom/sgsn/gprs_ranap.h b/include/osmocom/sgsn/gprs_ranap.h index 491ef6c..3c4f593 100644 --- a/include/osmocom/sgsn/gprs_ranap.h +++ b/include/osmocom/sgsn/gprs_ranap.h @@ -33,6 +33,13 @@ const struct RANAP_Cause *cause, int timeout);
+int sgsn_ranap_iu_tx_cl(struct sgsn_sccp_user_iups *scu_iups, + const struct osmo_sccp_addr *dst_addr, + struct msgb *msg); +int sgsn_ranap_iu_tx_error_ind(struct sgsn_sccp_user_iups *scu_iups, + const struct osmo_sccp_addr *dst_addr, + const RANAP_Cause_t *cause); + int sgsn_ranap_iu_rx_cl_msg(struct sgsn_sccp_user_iups *scu_iups, const struct osmo_scu_unitdata_param *ud_prim, const uint8_t *data, size_t len); diff --git a/src/sgsn/gprs_ranap.c b/src/sgsn/gprs_ranap.c index 38d3c34..f68e5e0 100644 --- a/src/sgsn/gprs_ranap.c +++ b/src/sgsn/gprs_ranap.c @@ -329,6 +329,30 @@ return sgsn_scu_iups_tx_data_req(uectx->scu_iups, uectx->conn_id, msg); }
+/* Send CL RANAP message over SCCP: */ +int sgsn_ranap_iu_tx_cl(struct sgsn_sccp_user_iups *scu_iups, + const struct osmo_sccp_addr *dst_addr, + struct msgb *msg) +{ + msg->l2h = msg->data; + return osmo_sccp_tx_unitdata_msg(scu_iups->scu, &scu_iups->local_sccp_addr, dst_addr, msg); +} + +/* Send RANAP Error Indication */ +int sgsn_ranap_iu_tx_error_ind(struct sgsn_sccp_user_iups *scu_iups, + const struct osmo_sccp_addr *dst_addr, + const RANAP_Cause_t *cause) +{ + RANAP_CN_DomainIndicator_t domain = RANAP_CN_DomainIndicator_ps_domain; + struct msgb *ranap_msg; + + ranap_msg = ranap_new_msg_error_ind(cause, NULL, &domain, NULL); + if (!ranap_msg) + return -ENOMEM; + + return sgsn_ranap_iu_tx_cl(scu_iups, dst_addr, ranap_msg); +} + /* Send Iu Release for the given UE connection. * If cause is NULL, Normal Release cause is sent, otherwise * the provided cause. */ @@ -647,19 +671,50 @@ const RANAP_ResetIEs_t *ies) { const RANAP_GlobalRNC_ID_t *grnc_id = NULL; + RANAP_Cause_t cause; + struct osmo_rnc_id rnc_id = {}; struct msgb *resp;
- /* FIXME: verify ies.cN_DomainIndicator */ + if (ies->presenceMask & ERRORINDICATIONIES_RANAP_CN_DOMAININDICATOR_PRESENT) { + if (ies->cN_DomainIndicator != RANAP_CN_DomainIndicator_ps_domain) { + LOGP(DRANAP, LOGL_ERROR, "Rx RESET: Unexpected CN Domain Indicator %d\n", + (int)ies->cN_DomainIndicator); + cause = (RANAP_Cause_t){ + .present = RANAP_Cause_PR_protocol, + .choice.protocol = RANAP_CauseProtocol_semantic_error, + }; + return sgsn_ranap_iu_tx_error_ind(scu_iups, &ud_prim->calling_addr, &cause); + } + } /* else: assume PS */
- if (ies->presenceMask & RESETIES_RANAP_GLOBALRNC_ID_PRESENT) - grnc_id = &ies->globalRNC_ID; + /* FIXME: support handling Extended RNC-ID instead of Global RNC-ID */ + + if (!(ies->presenceMask & RESETIES_RANAP_GLOBALRNC_ID_PRESENT)) { + LOGP(DRANAP, LOGL_ERROR, + "Rx RESET: Missing RANAP Global-RNC-ID IE\n"); + cause = (RANAP_Cause_t){ + .present = RANAP_Cause_PR_protocol, + .choice.protocol = RANAP_CauseProtocol_transfer_syntax_error, + }; + return sgsn_ranap_iu_tx_error_ind(scu_iups, &ud_prim->calling_addr, &cause); + } + grnc_id = &ies->globalRNC_ID; + + if (iu_grnc_id_parse(&rnc_id, &ies->globalRNC_ID) != 0) { + LOGP(DRANAP, LOGL_ERROR, + "Rx RESET: Failed to parse RANAP Global-RNC-ID IE\n"); + cause = (RANAP_Cause_t){ + .present = RANAP_Cause_PR_protocol, + .choice.protocol = RANAP_CauseProtocol_transfer_syntax_error, + }; + return sgsn_ranap_iu_tx_error_ind(scu_iups, &ud_prim->calling_addr, &cause); + }
/* send reset response */ resp = ranap_new_msg_reset_ack(ies->cN_DomainIndicator, grnc_id); if (!resp) return -ENOMEM; - resp->l2h = resp->data; - return osmo_sccp_tx_unitdata_msg(scu_iups->scu, &scu_iups->local_sccp_addr, &ud_prim->calling_addr, resp); + return sgsn_ranap_iu_tx_cl(scu_iups, &ud_prim->calling_addr, resp); }
static int ranap_handle_cl_err_ind(struct sgsn_sccp_user_iups *scu_iups,