From cdcfc80176118ab7de338bdaa0f5719c15b1cdac Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Wed, 9 Jun 2021 22:26:11 +0200 Subject: [PATCH] ran_msg_a.c: use gsm0808_create_cipher2() Use new API in Cipher Mode Command to prepare for A5/4 support. Depends: Ib3906085e0c6e5a496a9f755f0f786238a86ca34 (libosmocore) Related: SYS#5324 Change-Id: Ib238d367b8d5d07b6ab4cb2e48fbf4ce22ca4476 --- TODO-RELEASE | 1 + src/libmsc/ran_msg_a.c | 29 ++++++++++++++++------------- 2 files changed, 17 insertions(+), 13 deletions(-) diff --git a/TODO-RELEASE b/TODO-RELEASE index d0852fc9b..229706346 100644 --- a/TODO-RELEASE +++ b/TODO-RELEASE @@ -7,3 +7,4 @@ # If any interfaces have been added since the last public release: c:r:a + 1. # If any interfaces have been removed or changed since the last public release: c:r:0. #library what description / commit summary line +libosmocore >1.5.1 A5/4 support requires new API gsm0808_create_cipher2() diff --git a/src/libmsc/ran_msg_a.c b/src/libmsc/ran_msg_a.c index 4cce2899e..61e5024b9 100644 --- a/src/libmsc/ran_msg_a.c +++ b/src/libmsc/ran_msg_a.c @@ -1058,14 +1058,17 @@ osmo_static_assert(sizeof(((struct gsm0808_encrypt_info*)0)->key) >= sizeof(((st gsm0808_encrypt_info_key_fits_osmo_auth_vec_kc); static struct msgb *ran_a_make_cipher_mode_command(struct osmo_fsm_inst *fi, const struct ran_cipher_mode_command *cm) { - struct gsm0808_encrypt_info ei = {}; + struct gsm0808_cipher_mode_command cmc = { + .cipher_response_mode_present = true, + .cipher_response_mode = 1, /* 1: include IMEISV (3GPP TS 48.008 3.2.2.34) */ + }; + struct gsm0808_encrypt_info *ei = &cmc.ei; char buf[16 * 2 + 1]; - const uint8_t cipher_response_mode = 1; - if (make_encrypt_info_perm_algo(fi, &ei, cm->geran.a5_encryption_mask, cm->classmark)) + if (make_encrypt_info_perm_algo(fi, ei, cm->geran.a5_encryption_mask, cm->classmark)) return NULL; - if (ei.perm_algo_len == 0) { + if (ei->perm_algo_len == 0) { LOG_RAN_A_ENC(fi, LOGL_ERROR, "cannot start ciphering, no intersection between MSC-configured" " and MS-supported A5 algorithms. MSC: 0x%02x MS: %s\n", cm->geran.a5_encryption_mask, osmo_gsm48_classmark_a5_name(cm->classmark)); @@ -1076,26 +1079,26 @@ static struct msgb *ran_a_make_cipher_mode_command(struct osmo_fsm_inst *fi, con * tokens. vec->kc was calculated from the GSM algorithm and is not * necessarily a match for the UMTS AKA tokens. */ if (cm->geran.umts_aka) - osmo_auth_c3(ei.key, cm->vec->ck, cm->vec->ik); + osmo_auth_c3(ei->key, cm->vec->ck, cm->vec->ik); else - memcpy(ei.key, cm->vec->kc, sizeof(cm->vec->kc)); - ei.key_len = sizeof(cm->vec->kc); + memcpy(ei->key, cm->vec->kc, sizeof(cm->vec->kc)); + ei->key_len = sizeof(cm->vec->kc); /* Store chosen GERAN key where the caller asked it to be stored. * alg_id remains unknown until we receive a Cipher Mode Complete from the BSC */ if (cm->geran.chosen_key) { - if (ei.key_len > sizeof(cm->geran.chosen_key->key)) { + if (ei->key_len > sizeof(cm->geran.chosen_key->key)) { LOG_RAN_A_ENC(fi, LOGL_ERROR, "Chosen key is larger than I can store\n"); return NULL; } - memcpy(cm->geran.chosen_key->key, ei.key, ei.key_len); - cm->geran.chosen_key->key_len = ei.key_len; + memcpy(cm->geran.chosen_key->key, ei->key, ei->key_len); + cm->geran.chosen_key->key_len = ei->key_len; } LOG_RAN_A_ENC(fi, LOGL_DEBUG, "Tx BSSMAP CIPHER MODE COMMAND to BSC, %u ciphers (%s) key %s\n", - ei.perm_algo_len, osmo_hexdump_nospc(ei.perm_algo, ei.perm_algo_len), - osmo_hexdump_buf(buf, sizeof(buf), ei.key, ei.key_len, NULL, false)); - return gsm0808_create_cipher(&ei, cm->geran.retrieve_imeisv ? &cipher_response_mode : NULL); + ei->perm_algo_len, osmo_hexdump_nospc(ei->perm_algo, ei->perm_algo_len), + osmo_hexdump_buf(buf, sizeof(buf), ei->key, ei->key_len, NULL, false)); + return gsm0808_create_cipher2(&cmc); } struct msgb *ran_a_make_handover_request(struct osmo_fsm_inst *log_fi, const struct ran_handover_request *n)