diff options
| author | Neels Hofmeyr <neels@hofmeyr.de> | 2021-06-15 01:10:39 +0200 |
|---|---|---|
| committer | laforge <laforge@osmocom.org> | 2021-06-22 05:56:09 +0000 |
| commit | 68536ccf8b5d7ca6e29792c370bf5a6b275d9cf7 (patch) | |
| tree | c6db2dab25da36507889d551d1405e9eaa5fcf72 | |
| parent | 5ec7b65eed04bd1b26d92dc184ace1f1687410b6 (diff) | |
support A5/4 in inter-BSC Handover
inter-BSC into this BSC: from BSSMAP Handover Request, parse and store
Kc128. All else is already implemented: depending on the chosen
encryption algorithm, Kc128 will end up in the Channel Activation.
inter-BSC out of this BSC: nothing is needed to support A5/4, the BSSMAP
Handover Required message does not contain any encryption related
information. The MSC already knows the chosen algorithm.
Related: SYS#5324
Change-Id: I7e9590e8c96aa50086148863ad9a2741b978e614
| -rw-r--r-- | include/osmocom/bsc/gsm_data.h | 2 | ||||
| -rw-r--r-- | src/osmo-bsc/handover_fsm.c | 22 |
2 files changed, 21 insertions, 3 deletions
diff --git a/include/osmocom/bsc/gsm_data.h b/include/osmocom/bsc/gsm_data.h index 1755b92d7..c5d2b8612 100644 --- a/include/osmocom/bsc/gsm_data.h +++ b/include/osmocom/bsc/gsm_data.h @@ -241,6 +241,8 @@ struct handover_in_req { struct gsm0808_channel_type ct; struct gsm0808_speech_codec_list scl; struct gsm0808_encrypt_info ei; + bool kc128_present; + uint8_t kc128[16]; struct gsm_classmark classmark; /* chosen_encr_alg reflects the encoded value as in RSL_ENC_ALG_A5(a5_numer): * chosen_encr_alg == 1 means A5/0 i.e. no encryption, chosen_encr_alg == 4 means A5/3. diff --git a/src/osmo-bsc/handover_fsm.c b/src/osmo-bsc/handover_fsm.c index cae5167b4..5f4b8928a 100644 --- a/src/osmo-bsc/handover_fsm.c +++ b/src/osmo-bsc/handover_fsm.c @@ -454,6 +454,7 @@ static bool parse_ho_request(struct gsm_subscriber_connection *conn, const struc int payload_length; bool aoip = gscon_is_aoip(conn); bool sccplite = gscon_is_sccplite(conn); + bool has_a54 = false; if ((aoip && sccplite) || !(aoip || sccplite)) { LOG_HO(conn, LOGL_ERROR, "Received BSSMAP Handover Request, but conn is not" @@ -485,6 +486,15 @@ static bool parse_ho_request(struct gsm_subscriber_connection *conn, const struc return false; } + if ((e = TLVP_GET(tp, GSM0808_IE_KC_128))) { + if (e->len != 16) { + LOG_HO(conn, LOGL_ERROR, "Invalid length in Kc128 IE: %u bytes (expected 16)\n", e->len); + return false; + } + memcpy(req->kc128, e->val, 16); + req->kc128_present = true; + } + if ((e = TLVP_GET(tp, GSM0808_IE_CLASSMARK_INFORMATION_TYPE_1))) { if (e->len != sizeof(req->classmark.classmark1)) { LOG_HO(conn, LOGL_ERROR, "Classmark Information 1 has wrong size\n"); @@ -513,9 +523,10 @@ static bool parse_ho_request(struct gsm_subscriber_connection *conn, const struc req->chosen_encr_alg); } - LOG_HO(conn, LOGL_DEBUG, "Handover Request encryption info: chosen=A5/%u key=%s\n", - (req->chosen_encr_alg ? : 1) - 1, req->ei.key_len? - osmo_hexdump_nospc(req->ei.key, req->ei.key_len) : "none"); + LOG_HO(conn, LOGL_DEBUG, "Handover Request encryption info: chosen=A5/%u key=%s kc128=%s\n", + (req->chosen_encr_alg ? : 1) - 1, + req->ei.key_len ? osmo_hexdump_nospc(req->ei.key, req->ei.key_len) : "none", + has_a54 ? osmo_hexdump_nospc(req->kc128, 16) : "none"); if (TLVP_PRESENT(tp, GSM0808_IE_AOIP_TRASP_ADDR)) { int rc; @@ -720,6 +731,11 @@ void handover_start_inter_bsc_in(struct gsm_subscriber_connection *conn, info.encr.key_len = req->ei.key_len; } + if (req->kc128_present) { + memcpy(info.encr.kc128, req->kc128, 16); + info.encr.kc128_present = true; + } + if (req->last_eutran_plmn_valid) { conn->fast_return.allowed = ho->new_bts->srvcc_fast_return_allowed; conn->fast_return.last_eutran_plmn_valid = true; |