From 9c1e04e5802dfa25fcab3ca2c947897a1b7e7485 Mon Sep 17 00:00:00 2001 From: Alexander Couzens Date: Wed, 20 Jan 2021 14:50:31 +0100 Subject: gprs_ns2_vc_fsm: check NSVCI match the NSE The NSVCI must match the PDUs. The only exception is a RESET with dialect ipaccess. However those will be handled later. Change-Id: I8518bdb03e9e33b04b77a2a346d04c5d29544a6c --- src/gb/gprs_ns2_vc_fsm.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/src/gb/gprs_ns2_vc_fsm.c b/src/gb/gprs_ns2_vc_fsm.c index 3ec69097..d4f43207 100644 --- a/src/gb/gprs_ns2_vc_fsm.c +++ b/src/gb/gprs_ns2_vc_fsm.c @@ -750,11 +750,10 @@ int gprs_ns2_vc_rx(struct gprs_ns2_vc *nsvc, struct msgb *msg, struct tlv_parsed struct osmo_fsm_inst *fi = nsvc->fi; int rc = 0; uint8_t cause; - uint16_t nsei; + uint16_t nsei, nsvci; /* TODO: 7.2: on UNBLOCK/BLOCK: check if NS-VCI is correct, * if not answer STATUS with "NS-VC unknown" */ - /* TODO: handle RESET with different VCI */ /* TODO: handle BLOCK/UNBLOCK/ALIVE with different VCI */ if (gprs_ns2_validate(nsvc, nsh->pdu_type, msg, tp, &cause)) { @@ -777,6 +776,19 @@ int gprs_ns2_vc_rx(struct gprs_ns2_vc *nsvc, struct msgb *msg, struct tlv_parsed } } + if (nsvc->nsvci_is_valid && TLVP_PRESENT(tp, NS_IE_VCI)) { + nsvci = tlvp_val16be(tp, NS_IE_VCI); + if (nsvci != nsvc->nsvci) { + /* 48.016 ยง 7.3.1 send RESET_ACK to wrong NSVCI + ignore */ + if (nsh->pdu_type == NS_PDUT_RESET) + ns2_tx_reset_ack(nsvc); + + LOGNSVC(nsvc, LOGL_ERROR, "Rx %s with wrong NSVCI=%05u. Ignoring PDU.\n", + get_value_string(gprs_ns_pdu_strings, nsh->pdu_type), nsvci); + goto out; + } + } + switch (nsh->pdu_type) { case NS_PDUT_RESET: osmo_fsm_inst_dispatch(fi, GPRS_NS2_EV_RX_RESET, tp); -- cgit v1.2.3