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-rw-r--r--src/gprs/oap_client.c280
1 files changed, 0 insertions, 280 deletions
diff --git a/src/gprs/oap_client.c b/src/gprs/oap_client.c
deleted file mode 100644
index 9ff84a6e..00000000
--- a/src/gprs/oap_client.c
+++ /dev/null
@@ -1,280 +0,0 @@
-/* Osmocom Authentication Protocol API */
-
-/* (C) 2015 by Sysmocom s.f.m.c. GmbH
- * All Rights Reserved
- *
- * Author: Neels Hofmeyr
- *
- * 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 <http://www.gnu.org/licenses/>.
- *
- */
-
-#include <string.h>
-#include <errno.h>
-
-#include <osmocom/core/utils.h>
-#include <osmocom/crypt/auth.h>
-#include <osmocom/gsm/oap.h>
-
-#include <osmocom/sgsn/oap_client.h>
-#include <osmocom/sgsn/debug.h>
-
-int oap_client_init(struct oap_client_config *config,
- struct oap_client_state *state)
-{
- OSMO_ASSERT(state->state == OAP_UNINITIALIZED);
-
- if (!config)
- goto disable;
-
- if (config->client_id == 0)
- goto disable;
-
- if (config->secret_k_present == 0) {
- LOGP(DLOAP, LOGL_NOTICE, "OAP: client ID set, but secret K missing.\n");
- goto disable;
- }
-
- if (config->secret_opc_present == 0) {
- LOGP(DLOAP, LOGL_NOTICE, "OAP: client ID set, but secret OPC missing.\n");
- goto disable;
- }
-
- state->client_id = config->client_id;
- memcpy(state->secret_k, config->secret_k, sizeof(state->secret_k));
- memcpy(state->secret_opc, config->secret_opc, sizeof(state->secret_opc));
- state->state = OAP_INITIALIZED;
- return 0;
-
-disable:
- state->state = OAP_DISABLED;
- return 0;
-}
-
-/* From the given state and received RAND and AUTN octets, validate the
- * server's authenticity and formulate the matching milenage reply octets in
- * *tx_xres. The state is not modified.
- * On success, and if tx_res is not NULL, exactly 8 octets will be written to
- * *tx_res. If not NULL, tx_res must point at allocated memory of at least 8
- * octets. The caller will want to send XRES back to the server in a challenge
- * response message and update the state.
- * Return 0 on success; -1 if OAP is disabled; -2 if rx_random and rx_autn fail
- * the authentication check; -3 for any other errors. */
-static int oap_evaluate_challenge(const struct oap_client_state *state,
- const uint8_t *rx_random,
- const uint8_t *rx_autn,
- uint8_t *tx_xres)
-{
- struct osmo_auth_vector vec;
-
- struct osmo_sub_auth_data auth = {
- .type = OSMO_AUTH_TYPE_UMTS,
- .algo = OSMO_AUTH_ALG_MILENAGE,
- };
-
- osmo_static_assert(sizeof(((struct osmo_sub_auth_data*)0)->u.umts.k)
- == sizeof(state->secret_k), _secret_k_size_match);
- osmo_static_assert(sizeof(((struct osmo_sub_auth_data*)0)->u.umts.opc)
- == sizeof(state->secret_opc), _secret_opc_size_match);
-
- switch (state->state) {
- case OAP_UNINITIALIZED:
- case OAP_DISABLED:
- return -1;
- default:
- break;
- }
-
- memcpy(auth.u.umts.k, state->secret_k, sizeof(auth.u.umts.k));
- memcpy(auth.u.umts.opc, state->secret_opc, sizeof(auth.u.umts.opc));
- memset(auth.u.umts.amf, '\0', sizeof(auth.u.umts.amf));
- auth.u.umts.sqn = 41; /* TODO use incrementing sequence nr */
-
- memset(&vec, 0, sizeof(vec));
- osmo_auth_gen_vec(&vec, &auth, rx_random);
-
- if (vec.res_len != 8) {
- LOGP(DLOAP, LOGL_ERROR, "OAP: Expected XRES to be 8 octets, got %d\n",
- vec.res_len);
- return -3;
- }
-
- if (osmo_constant_time_cmp(vec.autn, rx_autn, sizeof(vec.autn)) != 0) {
- LOGP(DLOAP, LOGL_ERROR, "OAP: AUTN mismatch!\n");
- LOGP(DLOAP, LOGL_INFO, "OAP: AUTN from server: %s\n",
- osmo_hexdump_nospc(rx_autn, sizeof(vec.autn)));
- LOGP(DLOAP, LOGL_INFO, "OAP: AUTN expected: %s\n",
- osmo_hexdump_nospc(vec.autn, sizeof(vec.autn)));
- return -2;
- }
-
- if (tx_xres != NULL)
- memcpy(tx_xres, vec.res, 8);
- return 0;
-}
-
-struct msgb *oap_client_encoded(const struct osmo_oap_message *oap_msg)
-{
- struct msgb *msg = msgb_alloc_headroom(1000, 64, __func__);
- OSMO_ASSERT(msg);
- osmo_oap_encode(msg, oap_msg);
- return msg;
-}
-
-/* Create a new msgb containing an OAP registration message.
- * On error, return NULL. */
-static struct msgb* oap_msg_register(uint16_t client_id)
-{
- struct osmo_oap_message oap_msg = {0};
-
- if (client_id < 1) {
- LOGP(DLOAP, LOGL_ERROR, "OAP: Invalid client ID: %d\n", client_id);
- return NULL;
- }
-
- oap_msg.message_type = OAP_MSGT_REGISTER_REQUEST;
- oap_msg.client_id = client_id;
- return oap_client_encoded(&oap_msg);
-}
-
-int oap_client_register(struct oap_client_state *state, struct msgb **msg_tx)
-{
- *msg_tx = oap_msg_register(state->client_id);
- if (!(*msg_tx))
- return -1;
-
- state->state = OAP_REQUESTED_CHALLENGE;
- return 0;
-}
-
-/* Create a new msgb containing an OAP challenge response message.
- * xres must point at 8 octets to return as challenge response.
- * On error, return NULL. */
-static struct msgb* oap_msg_challenge_response(uint8_t *xres)
-{
- struct osmo_oap_message oap_reply = {0};
-
- oap_reply.message_type = OAP_MSGT_CHALLENGE_RESULT;
- memcpy(oap_reply.xres, xres, sizeof(oap_reply.xres));
- oap_reply.xres_present = 1;
- return oap_client_encoded(&oap_reply);
-}
-
-static int handle_challenge(struct oap_client_state *state,
- struct osmo_oap_message *oap_rx,
- struct msgb **msg_tx)
-{
- int rc;
- uint8_t xres[8];
-
- if (!(oap_rx->rand_present && oap_rx->autn_present)) {
- LOGP(DLOAP, LOGL_ERROR,
- "OAP challenge incomplete (rand_present: %d, autn_present: %d)\n",
- oap_rx->rand_present, oap_rx->autn_present);
- rc = -2;
- goto failure;
- }
-
- rc = oap_evaluate_challenge(state,
- oap_rx->rand,
- oap_rx->autn,
- xres);
- if (rc < 0)
- goto failure;
-
- *msg_tx = oap_msg_challenge_response(xres);
- if ((*msg_tx) == NULL) {
- rc = -1;
- goto failure;
- }
-
- state->state = OAP_SENT_CHALLENGE_RESULT;
- return 0;
-
-failure:
- OSMO_ASSERT(rc < 0);
- state->state = OAP_INITIALIZED;
- return rc;
-}
-
-int oap_client_handle(struct oap_client_state *state,
- const struct msgb *msg_rx, struct msgb **msg_tx)
-{
- uint8_t *data = msgb_l2(msg_rx);
- size_t data_len = msgb_l2len(msg_rx);
- struct osmo_oap_message oap_msg = {0};
- int rc = 0;
-
- *msg_tx = NULL;
-
- OSMO_ASSERT(data);
-
- rc = osmo_oap_decode(&oap_msg, data, data_len);
- if (rc < 0) {
- LOGP(DLOAP, LOGL_ERROR,
- "Decoding OAP message failed with error '%s' (%d)\n",
- get_value_string(gsm48_gmm_cause_names, -rc), -rc);
- return -10;
- }
-
- switch (state->state) {
- case OAP_UNINITIALIZED:
- LOGP(DLOAP, LOGL_ERROR,
- "Received OAP message %d, but the OAP client is"
- " not initialized\n", oap_msg.message_type);
- return -ENOTCONN;
- case OAP_DISABLED:
- LOGP(DLOAP, LOGL_ERROR,
- "Received OAP message %d, but the OAP client is"
- " disabled\n", oap_msg.message_type);
- return -ENOTCONN;
- default:
- break;
- }
-
- switch (oap_msg.message_type) {
- case OAP_MSGT_CHALLENGE_REQUEST:
- return handle_challenge(state, &oap_msg, msg_tx);
-
- case OAP_MSGT_REGISTER_RESULT:
- /* successfully registered */
- state->state = OAP_REGISTERED;
- break;
-
- case OAP_MSGT_REGISTER_ERROR:
- LOGP(DLOAP, LOGL_ERROR,
- "OAP registration failed\n");
- state->state = OAP_INITIALIZED;
- if (state->registration_failures < 3) {
- state->registration_failures ++;
- return oap_client_register(state, msg_tx);
- }
- return -11;
-
- case OAP_MSGT_REGISTER_REQUEST:
- case OAP_MSGT_CHALLENGE_RESULT:
- LOGP(DLOAP, LOGL_ERROR,
- "Received invalid OAP message type for OAP client side: %d\n",
- (int)oap_msg.message_type);
- return -12;
-
- default:
- LOGP(DLOAP, LOGL_ERROR,
- "Unknown OAP message type: %d\n",
- (int)oap_msg.message_type);
- return -13;
- }
-
- return 0;
-}