From 3b6fb0880c3ab1e23a3d7d738d073b00c2a794c2 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Mon, 25 Apr 2016 18:46:22 +0200 Subject: import gprs_gsup_message.[ch] from openbsc as gsup.[ch] Move those routines from OpenBSC to libosmogsm, so they can be re-used from other programs. I think it was a mistake to add them only inside the openbsc repository in the first place. We need to pay more attention to this in the future. --- src/gsm/Makefile.am | 3 +- src/gsm/gsup.c | 472 +++++++++++++++++++++++++++++++++++++++++++++++++ src/gsm/libosmogsm.map | 3 + 3 files changed, 477 insertions(+), 1 deletion(-) create mode 100644 src/gsm/gsup.c (limited to 'src') diff --git a/src/gsm/Makefile.am b/src/gsm/Makefile.am index 4326b357..781f153a 100644 --- a/src/gsm/Makefile.am +++ b/src/gsm/Makefile.am @@ -26,7 +26,8 @@ libgsmint_la_SOURCES = a5.c rxlev_stat.c tlv_parser.c comp128.c comp128v23.c \ auth_core.c auth_comp128v1.c auth_comp128v23.c \ auth_milenage.c milenage/aes-encblock.c \ milenage/aes-internal.c milenage/aes-internal-enc.c \ - milenage/milenage.c gan.c ipa.c gsm0341.c apn.c + milenage/milenage.c gan.c ipa.c gsm0341.c apn.c \ + gsup.c libgsmint_la_LDFLAGS = -no-undefined libgsmint_la_LIBADD = ../libosmocore.la diff --git a/src/gsm/gsup.c b/src/gsm/gsup.c new file mode 100644 index 00000000..7a439d48 --- /dev/null +++ b/src/gsm/gsup.c @@ -0,0 +1,472 @@ +/* Osmocom Subscriber Update Protocol message encoder/decoder */ + +/* + * (C) 2014 by Sysmocom s.f.m.c. GmbH + * (C) 2015 by Holger Hans Peter Freyther + * (C) 2016 by Harald Welte + * All Rights Reserved + * + * Author: Jacob Erlbeck + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see . + * + */ + +#include +#include +#include +#include +#include + +#include + +static int decode_pdp_info(uint8_t *data, size_t data_len, + struct osmo_gsup_pdp_info *pdp_info) +{ + int rc; + uint8_t tag; + uint8_t *value; + size_t value_len; + + /* specific parts */ + while (data_len > 0) { + enum osmo_gsup_iei iei; + + rc = osmo_shift_tlv(&data, &data_len, &tag, &value, &value_len); + if (rc < 0) + return -GMM_CAUSE_PROTO_ERR_UNSPEC; + + iei = tag; + + switch (iei) { + case OSMO_GSUP_PDP_CONTEXT_ID_IE: + pdp_info->context_id = osmo_decode_big_endian(value, value_len); + break; + + case OSMO_GSUP_PDP_TYPE_IE: + pdp_info->pdp_type = + osmo_decode_big_endian(value, value_len) & 0x0fff; + break; + + case OSMO_GSUP_ACCESS_POINT_NAME_IE: + pdp_info->apn_enc = value; + pdp_info->apn_enc_len = value_len; + break; + + case OSMO_GSUP_PDP_QOS_IE: + pdp_info->qos_enc = value; + pdp_info->qos_enc_len = value_len; + break; + + default: + LOGP(DLGSUP, LOGL_ERROR, + "GSUP IE type %d not expected in PDP info\n", iei); + continue; + } + } + + return 0; +} + +static int decode_auth_info(uint8_t *data, size_t data_len, + struct osmo_auth_vector *auth_vector) +{ + int rc; + uint8_t tag; + uint8_t *value; + size_t value_len; + enum osmo_gsup_iei iei; + uint8_t presence = 0; + + /* specific parts */ + while (data_len > 0) { + rc = osmo_shift_tlv(&data, &data_len, &tag, &value, &value_len); + if (rc < 0) + return -GMM_CAUSE_PROTO_ERR_UNSPEC; + + iei = tag; + + switch (iei) { + case OSMO_GSUP_RAND_IE: + if (value_len != sizeof(auth_vector->rand)) + goto parse_error; + + memcpy(auth_vector->rand, value, value_len); + presence |= (1 << 0); + break; + + case OSMO_GSUP_SRES_IE: + if (value_len != sizeof(auth_vector->sres)) + goto parse_error; + + memcpy(auth_vector->sres, value, value_len); + presence |= (1 << 1); + break; + + case OSMO_GSUP_KC_IE: + if (value_len != sizeof(auth_vector->kc)) + goto parse_error; + + memcpy(auth_vector->kc, value, value_len); + presence |= (1 << 2); + break; + + case OSMO_GSUP_IK_IE: + if (value_len != sizeof(auth_vector->ik)) + goto parse_error; + memcpy(auth_vector->ik, value, value_len); + presence |= (1 << 4); + break; + + case OSMO_GSUP_CK_IE: + if (value_len != sizeof(auth_vector->ck)) + goto parse_error; + memcpy(auth_vector->ck, value, value_len); + presence |= (1 << 5); + break; + + case OSMO_GSUP_AUTN_IE: + if (value_len != sizeof(auth_vector->autn)) + goto parse_error; + memcpy(auth_vector->autn, value, value_len); + presence |= (1 << 6); + break; + case OSMO_GSUP_RES_IE: + if (value_len > sizeof(auth_vector->res)) + goto parse_error; + memcpy(auth_vector->res, value, value_len); + auth_vector->res_len = value_len; + presence |= (1 << 7); + break; + + default: + LOGP(DLGSUP, LOGL_ERROR, + "GSUP IE type %d not expected in PDP info\n", iei); + continue; + } + } + + if (presence & 0x07) + auth_vector->auth_types |= OSMO_AUTH_TYPE_GSM; + if (presence & 0xf0) + auth_vector->auth_types |= OSMO_AUTH_TYPE_UMTS; + + return 0; + +parse_error: + LOGP(DLGSUP, LOGL_ERROR, + "GSUP IE type %d, length %zu invalid in PDP info\n", iei, value_len); + + return -1; +} + +/*! Decode (parse) a GSUP message + * \param[in] const_data input data to be parsed + * \param[in] data_len length of input (\a const_data) + * \param[out] gsup_msg callee-allocated output data structure + * \returns 0 on success; negative otherwise + */ +int osmo_gsup_decode(const uint8_t *const_data, size_t data_len, + struct osmo_gsup_message *gsup_msg) +{ + int rc; + uint8_t tag; + /* the shift/match functions expect non-const pointers, but we'll + * either copy the data or cast pointers back to const before returning + * them + */ + uint8_t *data = (uint8_t *)const_data; + uint8_t *value; + size_t value_len; + static const struct osmo_gsup_pdp_info empty_pdp_info = {0}; + static const struct osmo_auth_vector empty_auth_info = {0}; + static const struct osmo_gsup_message empty_gsup_message = {0}; + + *gsup_msg = empty_gsup_message; + + /* generic part */ + rc = osmo_shift_v_fixed(&data, &data_len, 1, &value); + if (rc < 0) + return -GMM_CAUSE_INV_MAND_INFO; + + gsup_msg->message_type = osmo_decode_big_endian(value, 1); + + rc = osmo_match_shift_tlv(&data, &data_len, OSMO_GSUP_IMSI_IE, + &value, &value_len); + + if (rc <= 0) + return -GMM_CAUSE_INV_MAND_INFO; + + if (value_len * 2 + 1 > sizeof(gsup_msg->imsi)) + return -GMM_CAUSE_INV_MAND_INFO; + + /* Note that gsm48_decode_bcd_number expects the number of encoded IMSI + * octets in the first octet. By coincidence (the TLV encoding) the byte + * before the value part already contains this length so we can use it + * here. + */ + OSMO_ASSERT(value[-1] == value_len); + gsm48_decode_bcd_number(gsup_msg->imsi, sizeof(gsup_msg->imsi), + value - 1, 0); + + /* specific parts */ + while (data_len > 0) { + enum osmo_gsup_iei iei; + struct osmo_gsup_pdp_info pdp_info; + struct osmo_auth_vector auth_info; + + rc = osmo_shift_tlv(&data, &data_len, &tag, &value, &value_len); + if (rc < 0) + return -GMM_CAUSE_PROTO_ERR_UNSPEC; + + iei = tag; + + switch (iei) { + case OSMO_GSUP_IMSI_IE: + case OSMO_GSUP_PDP_TYPE_IE: + case OSMO_GSUP_ACCESS_POINT_NAME_IE: + case OSMO_GSUP_RAND_IE: + case OSMO_GSUP_SRES_IE: + case OSMO_GSUP_KC_IE: + LOGP(DLGSUP, LOGL_NOTICE, + "GSUP IE type %d not expected (ignored)\n", iei); + continue; + + case OSMO_GSUP_CAUSE_IE: + gsup_msg->cause = osmo_decode_big_endian(value, value_len); + break; + + case OSMO_GSUP_CANCEL_TYPE_IE: + gsup_msg->cancel_type = + osmo_decode_big_endian(value, value_len) + 1; + break; + + case OSMO_GSUP_PDP_INFO_COMPL_IE: + gsup_msg->pdp_info_compl = 1; + break; + + case OSMO_GSUP_FREEZE_PTMSI_IE: + gsup_msg->freeze_ptmsi = 1; + break; + + case OSMO_GSUP_PDP_CONTEXT_ID_IE: + /* When these IE appear in the top-level part of the + * message, they are used by Delete Subscr Info to delete + * single entries. We don't have an extra list for + * these but use the PDP info list instead */ + + /* fall through */ + + case OSMO_GSUP_PDP_INFO_IE: + if (gsup_msg->num_pdp_infos >= OSMO_GSUP_MAX_NUM_PDP_INFO) { + LOGP(DLGSUP, LOGL_ERROR, + "GSUP IE type %d (PDP_INFO) max exceeded\n", + iei); + return -GMM_CAUSE_COND_IE_ERR; + } + + pdp_info = empty_pdp_info; + + if (iei == OSMO_GSUP_PDP_INFO_IE) { + rc = decode_pdp_info(value, value_len, &pdp_info); + if (rc < 0) + return rc; + pdp_info.have_info = 1; + } else { + pdp_info.context_id = + osmo_decode_big_endian(value, value_len); + } + + gsup_msg->pdp_infos[gsup_msg->num_pdp_infos++] = + pdp_info; + break; + + case OSMO_GSUP_AUTH_TUPLE_IE: + if (gsup_msg->num_auth_vectors >= OSMO_GSUP_MAX_NUM_AUTH_INFO) { + LOGP(DLGSUP, LOGL_ERROR, + "GSUP IE type %d (AUTH_INFO) max exceeded\n", + iei); + return -GMM_CAUSE_INV_MAND_INFO; + } + + auth_info = empty_auth_info; + + rc = decode_auth_info(value, value_len, &auth_info); + if (rc < 0) + return rc; + + gsup_msg->auth_vectors[gsup_msg->num_auth_vectors++] = + auth_info; + break; + + case OSMO_GSUP_AUTS_IE: + if (value_len != 16) { + LOGP(DLGSUP, LOGL_ERROR, + "AUTS length != 16 received\n"); + return -GMM_CAUSE_COND_IE_ERR; + } + gsup_msg->auts = value; + break; + + case OSMO_GSUP_MSISDN_IE: + gsup_msg->msisdn_enc = value; + gsup_msg->msisdn_enc_len = value_len; + break; + + case OSMO_GSUP_HLR_NUMBER_IE: + gsup_msg->hlr_enc = value; + gsup_msg->hlr_enc_len = value_len; + break; + + default: + LOGP(DLGSUP, LOGL_NOTICE, + "GSUP IE type %d unknown\n", iei); + continue; + } + } + + return 0; +} + +static void encode_pdp_info(struct msgb *msg, enum osmo_gsup_iei iei, + const struct osmo_gsup_pdp_info *pdp_info) +{ + uint8_t *len_field; + size_t old_len; + uint8_t u8; + + len_field = msgb_tlv_put(msg, iei, 0, NULL) - 1; + old_len = msgb_length(msg); + + u8 = pdp_info->context_id; + msgb_tlv_put(msg, OSMO_GSUP_PDP_CONTEXT_ID_IE, sizeof(u8), &u8); + + if (pdp_info->pdp_type) { + msgb_tlv_put(msg, OSMO_GSUP_PDP_TYPE_IE, + OSMO_GSUP_PDP_TYPE_SIZE, + osmo_encode_big_endian(pdp_info->pdp_type | 0xf000, + OSMO_GSUP_PDP_TYPE_SIZE)); + } + + if (pdp_info->apn_enc) { + msgb_tlv_put(msg, OSMO_GSUP_ACCESS_POINT_NAME_IE, + pdp_info->apn_enc_len, pdp_info->apn_enc); + } + + if (pdp_info->qos_enc) { + msgb_tlv_put(msg, OSMO_GSUP_PDP_QOS_IE, + pdp_info->qos_enc_len, pdp_info->qos_enc); + } + + /* Update length field */ + *len_field = msgb_length(msg) - old_len; +} + +static void encode_auth_info(struct msgb *msg, enum osmo_gsup_iei iei, + const struct osmo_auth_vector *auth_vector) +{ + uint8_t *len_field; + size_t old_len; + + len_field = msgb_tlv_put(msg, iei, 0, NULL) - 1; + old_len = msgb_length(msg); + + msgb_tlv_put(msg, OSMO_GSUP_RAND_IE, + sizeof(auth_vector->rand), auth_vector->rand); + + msgb_tlv_put(msg, OSMO_GSUP_SRES_IE, + sizeof(auth_vector->sres), auth_vector->sres); + + msgb_tlv_put(msg, OSMO_GSUP_KC_IE, + sizeof(auth_vector->kc), auth_vector->kc); + + /* Update length field */ + *len_field = msgb_length(msg) - old_len; +} + +/*! Encode a GSUP message + * \param[out] msg message buffer to which encoded message is written + * \param[in] gsup_msg \ref osmo_gsup_message data to be encoded + */ +void osmo_gsup_encode(struct msgb *msg, const struct osmo_gsup_message *gsup_msg) +{ + uint8_t u8; + int idx; + uint8_t bcd_buf[GSM48_MI_SIZE] = {0}; + size_t bcd_len; + + /* generic part */ + OSMO_ASSERT(gsup_msg->message_type); + msgb_v_put(msg, gsup_msg->message_type); + + bcd_len = gsm48_encode_bcd_number(bcd_buf, sizeof(bcd_buf), 0, + gsup_msg->imsi); + + OSMO_ASSERT(bcd_len > 1); + + /* Note that gsm48_encode_bcd_number puts the length into the first + * octet. Since msgb_tlv_put will add this length byte, we'll have to + * skip it */ + msgb_tlv_put(msg, OSMO_GSUP_IMSI_IE, bcd_len - 1, &bcd_buf[1]); + + /* specific parts */ + if (gsup_msg->msisdn_enc) + msgb_tlv_put(msg, OSMO_GSUP_MSISDN_IE, + gsup_msg->msisdn_enc_len, gsup_msg->msisdn_enc); + if (gsup_msg->hlr_enc) + msgb_tlv_put(msg, OSMO_GSUP_HLR_NUMBER_IE, + gsup_msg->hlr_enc_len, gsup_msg->hlr_enc); + + if ((u8 = gsup_msg->cause)) + msgb_tlv_put(msg, OSMO_GSUP_CAUSE_IE, sizeof(u8), &u8); + + if ((u8 = gsup_msg->cancel_type)) { + u8 -= 1; + msgb_tlv_put(msg, OSMO_GSUP_CANCEL_TYPE_IE, sizeof(u8), &u8); + } + + if (gsup_msg->pdp_info_compl) + msgb_tlv_put(msg, OSMO_GSUP_PDP_INFO_COMPL_IE, 0, &u8); + + if (gsup_msg->freeze_ptmsi) + msgb_tlv_put(msg, OSMO_GSUP_FREEZE_PTMSI_IE, 0, &u8); + + for (idx = 0; idx < gsup_msg->num_pdp_infos; idx++) { + const struct osmo_gsup_pdp_info *pdp_info; + + pdp_info = &gsup_msg->pdp_infos[idx]; + + if (pdp_info->context_id == 0) + continue; + + if (pdp_info->have_info) { + encode_pdp_info(msg, OSMO_GSUP_PDP_INFO_IE, pdp_info); + } else { + u8 = pdp_info->context_id; + msgb_tlv_put(msg, OSMO_GSUP_PDP_CONTEXT_ID_IE, + sizeof(u8), &u8); + } + } + + for (idx = 0; idx < gsup_msg->num_auth_vectors; idx++) { + const struct osmo_auth_vector *auth_vector; + + auth_vector = &gsup_msg->auth_vectors[idx]; + + encode_auth_info(msg, OSMO_GSUP_AUTH_TUPLE_IE, auth_vector); + } + + if (gsup_msg->auts) + msgb_tlv_put(msg, OSMO_GSUP_AUTS_IE, 16, gsup_msg->auts); +} diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map index 8bd0dbfe..e0d9dcbd 100644 --- a/src/gsm/libosmogsm.map +++ b/src/gsm/libosmogsm.map @@ -309,5 +309,8 @@ osmo_apn_qualify_from_imsi; osmo_apn_to_str; osmo_apn_from_str; +osmo_gsup_encode; +osmo_gsup_decode; + local: *; }; -- cgit v1.2.3