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authorNeels Hofmeyr <nhofmeyr@sysmocom.de>2015-10-12 11:57:34 +0200
committerHolger Hans Peter Freyther <holger@moiji-mobile.com>2015-11-02 12:56:41 +0100
commitd739f092be82fb01e53404b0a67bc0158063a843 (patch)
tree2e24dd5b48400c87fa97f577f1a148e122cacea0
parentd48f057328cfb82b192d935325eb5af1162c0ecc (diff)
oap: implement initial OAP API.
Add oap.[hc] and oap_messages.[hc]. Sponsored-by: On-Waves ehf
-rw-r--r--openbsc/include/openbsc/Makefile.am3
-rw-r--r--openbsc/include/openbsc/oap.h78
-rw-r--r--openbsc/include/openbsc/oap_messages.h70
-rw-r--r--openbsc/src/gprs/Makefile.am3
-rw-r--r--openbsc/src/gprs/oap.c256
-rw-r--r--openbsc/src/gprs/oap_messages.c178
6 files changed, 586 insertions, 2 deletions
diff --git a/openbsc/include/openbsc/Makefile.am b/openbsc/include/openbsc/Makefile.am
index 828f5bd..8a074c2 100644
--- a/openbsc/include/openbsc/Makefile.am
+++ b/openbsc/include/openbsc/Makefile.am
@@ -16,7 +16,8 @@ noinst_HEADERS = abis_nm.h abis_rsl.h db.h gsm_04_08.h gsm_data.h \
arfcn_range_encode.h nat_rewrite_trie.h bsc_nat_callstats.h \
osmux.h mgcp_transcode.h gprs_utils.h utils.h \
gprs_gb_parse.h smpp.h meas_feed.h gprs_gsup_messages.h \
- gprs_gsup_client.h bsc_msg_filter.h
+ gprs_gsup_client.h bsc_msg_filter.h \
+ oap.h oap_messages.h
openbsc_HEADERS = gsm_04_08.h meas_rep.h bsc_api.h
openbscdir = $(includedir)/openbsc
diff --git a/openbsc/include/openbsc/oap.h b/openbsc/include/openbsc/oap.h
new file mode 100644
index 0000000..2370cbe
--- /dev/null
+++ b/openbsc/include/openbsc/oap.h
@@ -0,0 +1,78 @@
+/* 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/>.
+ *
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+struct msgb;
+struct oap_message;
+
+/* This is the config part for vty. It is essentially copied in oap_state,
+ * where values are copied over once the config is considered valid. */
+struct oap_config {
+ uint16_t client_id;
+ int secret_k_present;
+ uint8_t secret_k[16];
+ int secret_opc_present;
+ uint8_t secret_opc[16];
+};
+
+/* The runtime state of the OAP client. client_id and the secrets are in fact
+ * duplicated from oap_config, so that a separate validation of the config data
+ * is possible, and so that only a struct oap_state* is passed around. */
+struct oap_state {
+ enum {
+ OAP_UNINITIALIZED = 0, /* just allocated. */
+ OAP_DISABLED, /* disabled by config. */
+ OAP_INITIALIZED, /* enabled, config is valid. */
+ OAP_REQUESTED_CHALLENGE,
+ OAP_SENT_CHALLENGE_RESULT,
+ OAP_REGISTERED
+ } state;
+ uint16_t client_id;
+ uint8_t secret_k[16];
+ uint8_t secret_opc[16];
+ int registration_failures;
+};
+
+/* From config, initialize state. Return 0 on success. */
+int oap_init(struct oap_config *config, struct oap_state *state);
+
+/* Construct an OAP registration message and return in *msg_tx. Use
+ * state->client_id and update state->state.
+ * Return 0 on success, or a negative value on error.
+ * If an error is returned, *msg_tx is guaranteed to be NULL. */
+int oap_register(struct oap_state *state, struct msgb **msg_tx);
+
+/* Decode and act on a received OAP message msg_rx. Update state->state. If a
+ * non-NULL pointer is returned in *msg_tx, that msgb should be sent to the OAP
+ * server (and freed) by the caller. The received msg_rx is not freed.
+ * Return 0 on success, or a negative value on error.
+ * If an error is returned, *msg_tx is guaranteed to be NULL. */
+int oap_handle(struct oap_state *state, const struct msgb *msg_rx, struct msgb **msg_tx);
+
+/* Allocate a msgb and in it, return the encoded oap_msg. Return NULL on
+ * error. (Like oap_encode(), but also allocates a msgb.)
+ * About the name: the idea is do_something(oap_encoded(my_struct)) */
+struct msgb *oap_encoded(const struct oap_message *oap_msg);
+
diff --git a/openbsc/include/openbsc/oap_messages.h b/openbsc/include/openbsc/oap_messages.h
new file mode 100644
index 0000000..a7a254c
--- /dev/null
+++ b/openbsc/include/openbsc/oap_messages.h
@@ -0,0 +1,70 @@
+/* Osmocom Authentication Protocol message encoder/decoder */
+
+/* (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/>.
+ *
+ */
+#pragma once
+
+#include <stdint.h>
+#include <openbsc/gsm_04_08_gprs.h>
+#include <openbsc/gsm_data.h>
+
+/* Some numbers are out of sequence because (so far) they match gprs_gsup_iei.
+ */
+enum oap_iei {
+ OAP_CAUSE_IE = 0x02,
+ OAP_RAND_IE = 0x20,
+ OAP_AUTN_IE = 0x23,
+ OAP_XRES_IE = 0x24,
+ OAP_AUTS_IE = 0x25,
+ OAP_CLIENT_ID_IE = 0x30,
+};
+
+enum oap_message_type {
+ OAP_MSGT_REGISTER_REQUEST = 0b00000100,
+ OAP_MSGT_REGISTER_ERROR = 0b00000101,
+ OAP_MSGT_REGISTER_RESULT = 0b00000110,
+
+ OAP_MSGT_CHALLENGE_REQUEST = 0b00001000,
+ OAP_MSGT_CHALLENGE_ERROR = 0b00001001,
+ OAP_MSGT_CHALLENGE_RESULT = 0b00001010,
+
+ OAP_MSGT_SYNC_REQUEST = 0b00001100,
+ OAP_MSGT_SYNC_ERROR = 0b00001101,
+ OAP_MSGT_SYNC_RESULT = 0b00001110,
+};
+
+struct oap_message {
+ enum oap_message_type message_type;
+ enum gsm48_gmm_cause cause;
+ uint16_t client_id;
+ int rand_present;
+ uint8_t rand[16];
+ int autn_present;
+ uint8_t autn[16];
+ int xres_present;
+ uint8_t xres[8];
+ int auts_present;
+ uint8_t auts[16];
+};
+
+int oap_decode(const uint8_t *data, size_t data_len,
+ struct oap_message *oap_msg);
+void oap_encode(struct msgb *msg, const struct oap_message *oap_msg);
+
diff --git a/openbsc/src/gprs/Makefile.am b/openbsc/src/gprs/Makefile.am
index f012003..c8e3696 100644
--- a/openbsc/src/gprs/Makefile.am
+++ b/openbsc/src/gprs/Makefile.am
@@ -27,7 +27,8 @@ osmo_sgsn_SOURCES = gprs_gmm.c gprs_sgsn.c gprs_sndcp.c gprs_sndcp_vty.c \
gprs_llc.c gprs_llc_parse.c gprs_llc_vty.c crc24.c \
sgsn_ctrl.c sgsn_auth.c gprs_subscriber.c \
gprs_gsup_messages.c gprs_utils.c gprs_gsup_client.c \
- gsm_04_08_gprs.c sgsn_cdr.c sgsn_ares.c
+ gsm_04_08_gprs.c sgsn_cdr.c sgsn_ares.c \
+ oap.c oap_messages.c
osmo_sgsn_LDADD = \
$(top_builddir)/src/libcommon/libcommon.a \
-lgtp $(OSMO_LIBS) $(LIBOSMOABIS_LIBS) $(LIBCARES_LIBS) \
diff --git a/openbsc/src/gprs/oap.c b/openbsc/src/gprs/oap.c
new file mode 100644
index 0000000..1426702
--- /dev/null
+++ b/openbsc/src/gprs/oap.c
@@ -0,0 +1,256 @@
+/* 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 <osmocom/crypt/auth.h>
+
+#include <openbsc/oap.h>
+#include <openbsc/utils.h>
+#include <openbsc/debug.h>
+#include <openbsc/oap_messages.h>
+
+int oap_init(struct oap_config *config, struct oap_state *state)
+{
+ OSMO_ASSERT(state->state == OAP_UNINITIALIZED);
+
+ if (config->client_id == 0)
+ goto disable;
+
+ if (config->secret_k_present == 0) {
+ LOGP(DGPRS, LOGL_NOTICE, "OAP: client ID set, but secret K missing.\n");
+ goto disable;
+ }
+
+ if (config->secret_opc_present == 0) {
+ LOGP(DGPRS, 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_state *state,
+ const uint8_t *rx_random,
+ const uint8_t *rx_autn,
+ uint8_t *tx_xres)
+{
+ 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;
+ }
+
+ struct osmo_auth_vector vec;
+
+ struct osmo_sub_auth_data auth = {
+ .type = OSMO_AUTH_TYPE_UMTS,
+ .algo = OSMO_AUTH_ALG_MILENAGE,
+ };
+
+ 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 = 42; /* TODO use incrementing sequence nr */
+
+ memset(&vec, 0, sizeof(vec));
+ osmo_auth_gen_vec(&vec, &auth, rx_random);
+
+ if (vec.res_len != 8) {
+ LOGP(DGPRS, LOGL_ERROR, "OAP: Expected XRES to be 8 octets, got %d\n",
+ vec.res_len);
+ return -3;
+ }
+
+ if (constant_time_cmp(vec.autn, rx_autn, sizeof(vec.autn)) != 0) {
+ LOGP(DGPRS, LOGL_ERROR, "OAP: AUTN mismatch!\n");
+ LOGP(DGPRS, LOGL_INFO, "OAP: AUTN from server: %s\n",
+ osmo_hexdump_nospc(rx_autn, sizeof(vec.autn)));
+ LOGP(DGPRS, 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_encoded(const struct oap_message *oap_msg)
+{
+ struct msgb *msg = msgb_alloc_headroom(1000, 64, __func__);
+ OSMO_ASSERT(msg);
+ 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)
+{
+ if (client_id < 1) {
+ LOGP(DGPRS, LOGL_ERROR, "OAP: Invalid client ID: %d\n", client_id);
+ return NULL;
+ }
+
+ struct oap_message oap_msg = {0};
+ oap_msg.message_type = OAP_MSGT_REGISTER_REQUEST;
+ oap_msg.client_id = client_id;
+ return oap_encoded(&oap_msg);
+}
+
+int oap_register(struct oap_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 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_encoded(&oap_reply);
+}
+
+static int handle_challenge(struct oap_state *state,
+ struct oap_message *oap_rx,
+ struct msgb **msg_tx)
+{
+ int rc;
+ if (!(oap_rx->rand_present && oap_rx->autn_present)) {
+ LOGP(DGPRS, LOGL_ERROR,
+ "OAP challenge incomplete (rand_present: %d, autn_present: %d)\n",
+ oap_rx->rand_present, oap_rx->autn_present);
+ rc = -2;
+ goto failure;
+ }
+
+ uint8_t xres[8];
+ 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_handle(struct oap_state *state, const struct msgb *msg_rx, struct msgb **msg_tx)
+{
+ *msg_tx = NULL;
+
+ uint8_t *data = msgb_l2(msg_rx);
+ size_t data_len = msgb_l2len(msg_rx);
+ int rc = 0;
+
+ struct oap_message oap_msg = {0};
+
+ OSMO_ASSERT(data);
+
+ rc = oap_decode(data, data_len, &oap_msg);
+ if (rc < 0) {
+ LOGP(DGPRS, LOGL_ERROR,
+ "Decoding OAP message failed with error '%s' (%d)\n",
+ get_value_string(gsm48_gmm_cause_names, -rc), -rc);
+ return -10;
+ }
+
+ 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(DGPRS, LOGL_ERROR,
+ "OAP registration failed\n");
+ state->state = OAP_INITIALIZED;
+ if (state->registration_failures < 3) {
+ state->registration_failures ++;
+ return oap_register(state, msg_tx);
+ }
+ return -11;
+
+ case OAP_MSGT_REGISTER_REQUEST:
+ case OAP_MSGT_CHALLENGE_RESULT:
+ LOGP(DGPRS, LOGL_ERROR,
+ "Received invalid OAP message type for OAP client side: %d\n",
+ (int)oap_msg.message_type);
+ return -12;
+
+ default:
+ LOGP(DGPRS, LOGL_ERROR,
+ "Unknown OAP message type: %d\n",
+ (int)oap_msg.message_type);
+ return -13;
+ }
+
+ return 0;
+}
diff --git a/openbsc/src/gprs/oap_messages.c b/openbsc/src/gprs/oap_messages.c
new file mode 100644
index 0000000..eb52053
--- /dev/null
+++ b/openbsc/src/gprs/oap_messages.c
@@ -0,0 +1,178 @@
+/* Osmocom Authentication Protocol message encoder/decoder */
+
+/* (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 <openbsc/oap_messages.h>
+
+#include <openbsc/debug.h>
+#include <openbsc/gprs_utils.h>
+#include <openbsc/utils.h>
+
+#include <osmocom/gsm/tlv.h>
+#include <osmocom/core/msgb.h>
+
+#include <stdint.h>
+
+
+int oap_decode(const uint8_t *const_data, size_t data_len,
+ struct oap_message *oap_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;
+
+ memset(oap_msg, 0, sizeof(*oap_msg));
+
+ /* message type */
+ rc = gprs_shift_v_fixed(&data, &data_len, 1, &value);
+ if (rc < 0)
+ return -GMM_CAUSE_INV_MAND_INFO;
+ oap_msg->message_type = decode_big_endian(value, 1);
+
+ /* specific parts */
+ while (data_len > 0) {
+ enum oap_iei iei;
+
+ rc = gprs_shift_tlv(&data, &data_len, &tag, &value, &value_len);
+ if (rc < 0)
+ return -GMM_CAUSE_PROTO_ERR_UNSPEC;
+
+ iei = tag;
+
+ switch (iei) {
+ case OAP_CLIENT_ID_IE:
+ if (value_len != 2) {
+ LOGP(DGPRS, LOGL_NOTICE,
+ "OAP IE type client ID (%d) should be 2 octets, but has %d\n",
+ (int)iei, (int)value_len);
+ return -GMM_CAUSE_PROTO_ERR_UNSPEC;
+ }
+
+ oap_msg->client_id = decode_big_endian(value, value_len);
+
+ if (oap_msg->client_id == 0) {
+ LOGP(DGPRS, LOGL_NOTICE,
+ "OAP IE type client ID (%d): client ID must be nonzero.\n",
+ (int)iei);
+ return -GMM_CAUSE_PROTO_ERR_UNSPEC;
+ }
+ break;
+
+ case OAP_AUTN_IE:
+ if (value_len != sizeof(oap_msg->autn)) {
+ LOGP(DGPRS, LOGL_NOTICE,
+ "OAP IE type AUTN (%d) should be %d octets, but has %d\n",
+ (int)iei, (int)sizeof(oap_msg->autn), (int)value_len);
+ return -GMM_CAUSE_PROTO_ERR_UNSPEC;
+ }
+ memcpy(oap_msg->autn, value, value_len);
+ oap_msg->autn_present = value_len;
+ break;
+
+ case OAP_RAND_IE:
+ if (value_len != sizeof(oap_msg->rand)) {
+ LOGP(DGPRS, LOGL_NOTICE,
+ "OAP IE type RAND (%d) should be %d octets, but has %d\n",
+ (int)iei, (int)sizeof(oap_msg->rand), (int)value_len);
+ return -GMM_CAUSE_PROTO_ERR_UNSPEC;
+ }
+ memcpy(oap_msg->rand, value, value_len);
+ oap_msg->rand_present = value_len;
+ break;
+
+ case OAP_XRES_IE:
+ if (value_len != sizeof(oap_msg->xres)) {
+ LOGP(DGPRS, LOGL_NOTICE,
+ "OAP IE type XRES (%d) should be %d octets, but has %d\n",
+ (int)iei, (int)sizeof(oap_msg->xres), (int)value_len);
+ return -GMM_CAUSE_PROTO_ERR_UNSPEC;
+ }
+ memcpy(oap_msg->xres, value, value_len);
+ oap_msg->xres_present = value_len;
+ break;
+
+ case OAP_AUTS_IE:
+ if (value_len != sizeof(oap_msg->auts)) {
+ LOGP(DGPRS, LOGL_NOTICE,
+ "OAP IE type AUTS (%d) should be %d octets, but has %d\n",
+ (int)iei, (int)sizeof(oap_msg->auts), (int)value_len);
+ return -GMM_CAUSE_PROTO_ERR_UNSPEC;
+ }
+ memcpy(oap_msg->auts, value, value_len);
+ oap_msg->auts_present = value_len;
+ break;
+
+ case OAP_CAUSE_IE:
+ if (value_len > 1) {
+ LOGP(DGPRS, LOGL_ERROR,
+ "OAP cause may not exceed one octet, is %d", (int)value_len);
+ return -GMM_CAUSE_PROTO_ERR_UNSPEC;
+ }
+ oap_msg->cause = *value;
+ break;
+
+ default:
+ LOGP(DGPRS, LOGL_NOTICE,
+ "OAP IE type %d unknown\n", iei);
+ continue;
+ }
+ }
+
+ return 0;
+}
+
+void oap_encode(struct msgb *msg, const struct oap_message *oap_msg)
+{
+ uint8_t u8;
+
+ /* generic part */
+ OSMO_ASSERT(oap_msg->message_type);
+ msgb_v_put(msg, (uint8_t)oap_msg->message_type);
+
+ /* specific parts */
+ if ((u8 = oap_msg->cause))
+ msgb_tlv_put(msg, OAP_CAUSE_IE, sizeof(u8), &u8);
+
+ if (oap_msg->client_id > 0)
+ msgb_tlv_put(msg, OAP_CLIENT_ID_IE, sizeof(oap_msg->client_id),
+ encode_big_endian(oap_msg->client_id, sizeof(oap_msg->client_id)));
+
+ if (oap_msg->rand_present)
+ msgb_tlv_put(msg, OAP_RAND_IE, sizeof(oap_msg->rand), oap_msg->rand);
+
+ if (oap_msg->autn_present)
+ msgb_tlv_put(msg, OAP_AUTN_IE, sizeof(oap_msg->autn), oap_msg->autn);
+
+ if (oap_msg->auts_present)
+ msgb_tlv_put(msg, OAP_AUTS_IE, sizeof(oap_msg->auts), oap_msg->auts);
+
+ if (oap_msg->xres_present)
+ msgb_tlv_put(msg, OAP_XRES_IE, sizeof(oap_msg->xres), oap_msg->xres);
+
+ msg->l2h = msg->data;
+}
+