From ed651d2485a51b57bf6090f4f58fd356118c6835 Mon Sep 17 00:00:00 2001 From: Max Date: Wed, 7 Nov 2018 15:25:05 +0100 Subject: Support cipher mode reject with extended cause * add function to generate cipher mode reject with extended (2-byte) Cause IE * add function to get (extended) Cause value * add corresponding (extended cause) test * update existing (non-extended cause) test * use enum as a parameter for existing non-extended version to make interface more unified Change-Id: Id5509b94a18180a44f45300caaa02b843c166fa3 Related: OS#3187 --- include/osmocom/gsm/gsm0808.h | 1 + include/osmocom/gsm/gsm0808_utils.h | 2 ++ src/gsm/gsm0808.c | 24 ++++++++++++++++++++ src/gsm/gsm0808_utils.c | 16 ++++++++++++++ src/gsm/libosmogsm.map | 2 ++ tests/gsm0808/gsm0808_test.c | 44 ++++++++++++++++++++++++++++++++++++- tests/gsm0808/gsm0808_test.ok | 1 + 7 files changed, 89 insertions(+), 1 deletion(-) diff --git a/include/osmocom/gsm/gsm0808.h b/include/osmocom/gsm/gsm0808.h index 66f7c277..9b19d691 100644 --- a/include/osmocom/gsm/gsm0808.h +++ b/include/osmocom/gsm/gsm0808.h @@ -51,6 +51,7 @@ struct msgb *gsm0808_create_cipher(const struct gsm0808_encrypt_info *ei, const uint8_t *cipher_response_mode); struct msgb *gsm0808_create_cipher_complete(struct msgb *layer3, uint8_t alg_id); struct msgb *gsm0808_create_cipher_reject(enum gsm0808_cause cause); +struct msgb *gsm0808_create_cipher_reject_ext(enum gsm0808_cause_class class, uint8_t ext); struct msgb *gsm0808_create_classmark_request(); struct msgb *gsm0808_create_classmark_update(const uint8_t *cm2, uint8_t cm2_len, const uint8_t *cm3, uint8_t cm3_len); diff --git a/include/osmocom/gsm/gsm0808_utils.h b/include/osmocom/gsm/gsm0808_utils.h index b56e2635..c22d0a9b 100644 --- a/include/osmocom/gsm/gsm0808_utils.h +++ b/include/osmocom/gsm/gsm0808_utils.h @@ -120,6 +120,8 @@ static inline bool gsm0808_cause_ext(enum gsm0808_cause cause) return (cause & 0x80) && !(cause & 0x0F); } +int gsm0808_get_cipher_reject_cause(const struct tlv_parsed *tp); + /*! \returns 3GPP TS 48.008 3.2.2.49 Current Channel Type 1 from enum gsm_chan_t. */ static inline uint8_t gsm0808_current_channel_type_1(enum gsm_chan_t type) { diff --git a/src/gsm/gsm0808.c b/src/gsm/gsm0808.c index c413688c..a84e717d 100644 --- a/src/gsm/gsm0808.c +++ b/src/gsm/gsm0808.c @@ -283,6 +283,30 @@ struct msgb *gsm0808_create_cipher_reject(enum gsm0808_cause cause) return msg; } +/*! Create BSSMAP Cipher Mode Reject message + * \param[in] class 3GPP TS 08.08 §3.2.2.5 cause's class + * \param[in] ext 3GPP TS 08.08 §3.2.2.5 cause value (national application extension) + * \returns callee-allocated msgb with BSSMAP Cipher Mode Reject message */ +struct msgb *gsm0808_create_cipher_reject_ext(enum gsm0808_cause_class class, uint8_t ext) +{ + uint8_t c[2]; + struct msgb *msg = msgb_alloc_headroom(BSSMAP_MSG_SIZE, BSSMAP_MSG_HEADROOM, + "bssmap: cipher mode reject"); + if (!msg) + return NULL; + + c[0] = 0x80 | (class << 4); /* set the high bit to indicate extended cause */ + c[1] = ext; + + msgb_v_put(msg, BSS_MAP_MSG_CIPHER_MODE_REJECT); + + msgb_tlv_put(msg, GSM0808_IE_CAUSE, 2, c); + + msg->l3h = msgb_tv_push(msg, BSSAP_MSG_BSS_MANAGEMENT, msgb_length(msg)); + + return msg; +} + /*! Create BSSMAP LCLS CONNECT CONTROL message (TS 48.008 3.2.1.91). * \param[in] config LCLS Configuration * \param[in] control LCLS Connection Status Control diff --git a/src/gsm/gsm0808_utils.c b/src/gsm/gsm0808_utils.c index 2348105d..c58d8284 100644 --- a/src/gsm/gsm0808_utils.c +++ b/src/gsm/gsm0808_utils.c @@ -1235,6 +1235,22 @@ void gsm48_mr_cfg_from_gsm0808_sc_cfg(struct gsm48_multi_rate_conf *cfg, cfg->icmi = 1; } +int gsm0808_get_cipher_reject_cause(const struct tlv_parsed *tp) +{ + const uint8_t *buf = TLVP_VAL_MINLEN(tp, GSM0808_IE_CAUSE, 1); + + if (!buf) + return -EBADMSG; + + if (TLVP_LEN(tp, GSM0808_IE_CAUSE) > 1) { + if (!gsm0808_cause_ext(buf[0])) + return -EINVAL; + return buf[1]; + } + + return buf[0]; +} + /*! Print a human readable name of the cell identifier to the char buffer. * This is useful both for struct gsm0808_cell_id and struct gsm0808_cell_id_list2. * See also gsm0808_cell_id_name() and gsm0808_cell_id_list_name(). diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map index 32e4ce95..217dcc39 100644 --- a/src/gsm/libosmogsm.map +++ b/src/gsm/libosmogsm.map @@ -157,6 +157,8 @@ gsm0808_create_ass_fail; gsm0808_create_cipher; gsm0808_create_cipher_complete; gsm0808_create_cipher_reject; +gsm0808_create_cipher_reject_ext; +gsm0808_get_cipher_reject_cause; gsm0808_create_classmark_request; gsm0808_create_classmark_update; gsm0808_create_clear_command; diff --git a/tests/gsm0808/gsm0808_test.c b/tests/gsm0808/gsm0808_test.c index 671b8399..197ec06d 100644 --- a/tests/gsm0808/gsm0808_test.c +++ b/tests/gsm0808/gsm0808_test.c @@ -250,14 +250,55 @@ static void test_create_cipher_complete() msgb_free(l3); } +static inline void parse_cipher_reject(struct msgb *msg, uint8_t exp) +{ + struct tlv_parsed tp; + int rc; + + /* skip header and message type so we can parse Cause IE directly */ + msg->l2h = msgb_data(msg) + sizeof(struct bssmap_header) + 1; + + rc = osmo_bssap_tlv_parse(&tp, msg->l2h, msgb_l2len(msg)); + if (rc < 0) + printf("FIXME: failed (%d) to parse created message %s\n", rc, msgb_hexdump(msg)); + + rc = gsm0808_get_cipher_reject_cause(&tp); + if (rc < 0) + printf("FIXME: failed (%s) to extract Cause from created message %s\n", + strerror(-rc), msgb_hexdump(msg)); + + if (exp != (enum gsm0808_cause)rc) + printf("FIXME: wrong Cause %d != %u (" OSMO_BIN_SPEC ") extracted from created message %s\n", + rc, exp, OSMO_BIT_PRINT(exp), msgb_hexdump(msg)); +} + static void test_create_cipher_reject() { static const uint8_t res[] = { 0x00, 0x04, 0x59, 0x04, 0x01, 0x23 }; + enum gsm0808_cause cause = GSM0808_CAUSE_CCCH_OVERLOAD; struct msgb *msg; printf("Testing creating Cipher Reject\n"); - msg = gsm0808_create_cipher_reject(GSM0808_CAUSE_CCCH_OVERLOAD); + msg = gsm0808_create_cipher_reject(cause); + VERIFY(msg, res, ARRAY_SIZE(res)); + + parse_cipher_reject(msg, cause); + + msgb_free(msg); +} + +static void test_create_cipher_reject_ext() +{ + static const uint8_t res[] = { 0x00, 0x05, 0x59, 0x04, 0x02, 0xd0, 0xFA }; + uint8_t cause = 0xFA; + struct msgb *msg; + + printf("Testing creating Cipher Reject (extended)\n"); + msg = gsm0808_create_cipher_reject_ext(GSM0808_CAUSE_CLASS_INVAL, cause); VERIFY(msg, res, ARRAY_SIZE(res)); + + parse_cipher_reject(msg, cause); + msgb_free(msg); } @@ -1738,6 +1779,7 @@ int main(int argc, char **argv) test_create_cipher(); test_create_cipher_complete(); test_create_cipher_reject(); + test_create_cipher_reject_ext(); test_create_cm_u(); test_create_sapi_reject(); test_create_ass(); diff --git a/tests/gsm0808/gsm0808_test.ok b/tests/gsm0808/gsm0808_test.ok index 58bc5099..a48cf1d5 100644 --- a/tests/gsm0808/gsm0808_test.ok +++ b/tests/gsm0808/gsm0808_test.ok @@ -8,6 +8,7 @@ Testing creating Clear Complete Testing creating Chipher Mode Command Testing creating Cipher Complete Testing creating Cipher Reject +Testing creating Cipher Reject (extended) Testing creating CM U Testing creating SAPI Reject Testing creating Assignment Request -- cgit v1.2.3