--- /dev/null
+/*
+ * hostapd / EAP-AKA (RFC 4187) and EAP-AKA' (draft-arkko-eap-aka-kdf)
+ * Copyright (c) 2005-2008, Jouni Malinen <j@w1.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "crypto/sha256.h"
+#include "crypto/crypto.h"
+#include "eap_common/eap_sim_common.h"
+#include "eap_server/eap_i.h"
+#include "eap_server/eap_sim_db.h"
+
+
+struct eap_aka_data {
+ u8 mk[EAP_SIM_MK_LEN];
+ u8 nonce_s[EAP_SIM_NONCE_S_LEN];
+ u8 k_aut[EAP_AKA_PRIME_K_AUT_LEN];
+ u8 k_encr[EAP_SIM_K_ENCR_LEN];
+ u8 k_re[EAP_AKA_PRIME_K_RE_LEN]; /* EAP-AKA' only */
+ u8 msk[EAP_SIM_KEYING_DATA_LEN];
+ u8 emsk[EAP_EMSK_LEN];
+ u8 rand[EAP_AKA_RAND_LEN];
+ u8 autn[EAP_AKA_AUTN_LEN];
+ u8 ck[EAP_AKA_CK_LEN];
+ u8 ik[EAP_AKA_IK_LEN];
+ u8 res[EAP_AKA_RES_MAX_LEN];
+ size_t res_len;
+ enum {
+ IDENTITY, CHALLENGE, REAUTH, NOTIFICATION, SUCCESS, FAILURE
+ } state;
+ char *next_pseudonym;
+ char *next_reauth_id;
+ u16 counter;
+ struct eap_sim_reauth *reauth;
+ int auts_reported; /* whether the current AUTS has been reported to the
+ * eap_sim_db */
+ u16 notification;
+ int use_result_ind;
+
+ struct wpabuf *id_msgs;
+ int pending_id;
+ u8 eap_method;
+ u8 *network_name;
+ size_t network_name_len;
+ u16 kdf;
+};
+
+
+static void eap_aka_determine_identity(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ int before_identity, int after_reauth);
+
+
+static const char * eap_aka_state_txt(int state)
+{
+ switch (state) {
+ case IDENTITY:
+ return "IDENTITY";
+ case CHALLENGE:
+ return "CHALLENGE";
+ case REAUTH:
+ return "REAUTH";
+ case SUCCESS:
+ return "SUCCESS";
+ case FAILURE:
+ return "FAILURE";
+ case NOTIFICATION:
+ return "NOTIFICATION";
+ default:
+ return "Unknown?!";
+ }
+}
+
+
+static void eap_aka_state(struct eap_aka_data *data, int state)
+{
+ wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
+ eap_aka_state_txt(data->state),
+ eap_aka_state_txt(state));
+ data->state = state;
+}
+
+
+static void * eap_aka_init(struct eap_sm *sm)
+{
+ struct eap_aka_data *data;
+
+ if (sm->eap_sim_db_priv == NULL) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: eap_sim_db not configured");
+ return NULL;
+ }
+
+ data = os_zalloc(sizeof(*data));
+ if (data == NULL)
+ return NULL;
+
+ data->eap_method = EAP_TYPE_AKA;
+
+ data->state = IDENTITY;
+ eap_aka_determine_identity(sm, data, 1, 0);
+ data->pending_id = -1;
+
+ return data;
+}
+
+
+#ifdef EAP_SERVER_AKA_PRIME
+static void * eap_aka_prime_init(struct eap_sm *sm)
+{
+ struct eap_aka_data *data;
+ /* TODO: make ANID configurable; see 3GPP TS 24.302 */
+ char *network_name = "WLAN";
+
+ if (sm->eap_sim_db_priv == NULL) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: eap_sim_db not configured");
+ return NULL;
+ }
+
+ data = os_zalloc(sizeof(*data));
+ if (data == NULL)
+ return NULL;
+
+ data->eap_method = EAP_TYPE_AKA_PRIME;
+ data->network_name = os_malloc(os_strlen(network_name));
+ if (data->network_name == NULL) {
+ os_free(data);
+ return NULL;
+ }
+
+ data->network_name_len = os_strlen(network_name);
+ os_memcpy(data->network_name, network_name, data->network_name_len);
+
+ data->state = IDENTITY;
+ eap_aka_determine_identity(sm, data, 1, 0);
+ data->pending_id = -1;
+
+ return data;
+}
+#endif /* EAP_SERVER_AKA_PRIME */
+
+
+static void eap_aka_reset(struct eap_sm *sm, void *priv)
+{
+ struct eap_aka_data *data = priv;
+ os_free(data->next_pseudonym);
+ os_free(data->next_reauth_id);
+ wpabuf_free(data->id_msgs);
+ os_free(data->network_name);
+ os_free(data);
+}
+
+
+static int eap_aka_add_id_msg(struct eap_aka_data *data,
+ const struct wpabuf *msg)
+{
+ if (msg == NULL)
+ return -1;
+
+ if (data->id_msgs == NULL) {
+ data->id_msgs = wpabuf_dup(msg);
+ return data->id_msgs == NULL ? -1 : 0;
+ }
+
+ if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
+ return -1;
+ wpabuf_put_buf(data->id_msgs, msg);
+
+ return 0;
+}
+
+
+static void eap_aka_add_checkcode(struct eap_aka_data *data,
+ struct eap_sim_msg *msg)
+{
+ const u8 *addr;
+ size_t len;
+ u8 hash[SHA256_MAC_LEN];
+
+ wpa_printf(MSG_DEBUG, " AT_CHECKCODE");
+
+ if (data->id_msgs == NULL) {
+ /*
+ * No EAP-AKA/Identity packets were exchanged - send empty
+ * checkcode.
+ */
+ eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
+ return;
+ }
+
+ /* Checkcode is SHA1 hash over all EAP-AKA/Identity packets. */
+ addr = wpabuf_head(data->id_msgs);
+ len = wpabuf_len(data->id_msgs);
+ wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
+ if (data->eap_method == EAP_TYPE_AKA_PRIME)
+ sha256_vector(1, &addr, &len, hash);
+ else
+ sha1_vector(1, &addr, &len, hash);
+
+ eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
+ data->eap_method == EAP_TYPE_AKA_PRIME ?
+ EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
+}
+
+
+static int eap_aka_verify_checkcode(struct eap_aka_data *data,
+ const u8 *checkcode, size_t checkcode_len)
+{
+ const u8 *addr;
+ size_t len;
+ u8 hash[SHA256_MAC_LEN];
+ size_t hash_len;
+
+ if (checkcode == NULL)
+ return -1;
+
+ if (data->id_msgs == NULL) {
+ if (checkcode_len != 0) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from peer "
+ "indicates that AKA/Identity messages were "
+ "used, but they were not");
+ return -1;
+ }
+ return 0;
+ }
+
+ hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
+ EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
+
+ if (checkcode_len != hash_len) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from peer indicates "
+ "that AKA/Identity message were not used, but they "
+ "were");
+ return -1;
+ }
+
+ /* Checkcode is SHA1 hash over all EAP-AKA/Identity packets. */
+ addr = wpabuf_head(data->id_msgs);
+ len = wpabuf_len(data->id_msgs);
+ if (data->eap_method == EAP_TYPE_AKA_PRIME)
+ sha256_vector(1, &addr, &len, hash);
+ else
+ sha1_vector(1, &addr, &len, hash);
+
+ if (os_memcmp(hash, checkcode, hash_len) != 0) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
+ return -1;
+ }
+
+ return 0;
+}
+
+
+static struct wpabuf * eap_aka_build_identity(struct eap_sm *sm,
+ struct eap_aka_data *data, u8 id)
+{
+ struct eap_sim_msg *msg;
+ struct wpabuf *buf;
+
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Identity");
+ msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
+ EAP_AKA_SUBTYPE_IDENTITY);
+ if (eap_sim_db_identity_known(sm->eap_sim_db_priv, sm->identity,
+ sm->identity_len)) {
+ wpa_printf(MSG_DEBUG, " AT_PERMANENT_ID_REQ");
+ eap_sim_msg_add(msg, EAP_SIM_AT_PERMANENT_ID_REQ, 0, NULL, 0);
+ } else {
+ /*
+ * RFC 4187, Chap. 4.1.4 recommends that identity from EAP is
+ * ignored and the AKA/Identity is used to request the
+ * identity.
+ */
+ wpa_printf(MSG_DEBUG, " AT_ANY_ID_REQ");
+ eap_sim_msg_add(msg, EAP_SIM_AT_ANY_ID_REQ, 0, NULL, 0);
+ }
+ buf = eap_sim_msg_finish(msg, NULL, NULL, 0);
+ if (eap_aka_add_id_msg(data, buf) < 0) {
+ wpabuf_free(buf);
+ return NULL;
+ }
+ data->pending_id = id;
+ return buf;
+}
+
+
+static int eap_aka_build_encr(struct eap_sm *sm, struct eap_aka_data *data,
+ struct eap_sim_msg *msg, u16 counter,
+ const u8 *nonce_s)
+{
+ os_free(data->next_pseudonym);
+ data->next_pseudonym =
+ eap_sim_db_get_next_pseudonym(sm->eap_sim_db_priv, 1);
+ os_free(data->next_reauth_id);
+ if (data->counter <= EAP_AKA_MAX_FAST_REAUTHS) {
+ data->next_reauth_id =
+ eap_sim_db_get_next_reauth_id(sm->eap_sim_db_priv, 1);
+ } else {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Max fast re-authentication "
+ "count exceeded - force full authentication");
+ data->next_reauth_id = NULL;
+ }
+
+ if (data->next_pseudonym == NULL && data->next_reauth_id == NULL &&
+ counter == 0 && nonce_s == NULL)
+ return 0;
+
+ wpa_printf(MSG_DEBUG, " AT_IV");
+ wpa_printf(MSG_DEBUG, " AT_ENCR_DATA");
+ eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
+
+ if (counter > 0) {
+ wpa_printf(MSG_DEBUG, " *AT_COUNTER (%u)", counter);
+ eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
+ }
+
+ if (nonce_s) {
+ wpa_printf(MSG_DEBUG, " *AT_NONCE_S");
+ eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_S, 0, nonce_s,
+ EAP_SIM_NONCE_S_LEN);
+ }
+
+ if (data->next_pseudonym) {
+ wpa_printf(MSG_DEBUG, " *AT_NEXT_PSEUDONYM (%s)",
+ data->next_pseudonym);
+ eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_PSEUDONYM,
+ os_strlen(data->next_pseudonym),
+ (u8 *) data->next_pseudonym,
+ os_strlen(data->next_pseudonym));
+ }
+
+ if (data->next_reauth_id) {
+ wpa_printf(MSG_DEBUG, " *AT_NEXT_REAUTH_ID (%s)",
+ data->next_reauth_id);
+ eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_REAUTH_ID,
+ os_strlen(data->next_reauth_id),
+ (u8 *) data->next_reauth_id,
+ os_strlen(data->next_reauth_id));
+ }
+
+ if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
+ "AT_ENCR_DATA");
+ return -1;
+ }
+
+ return 0;
+}
+
+
+static struct wpabuf * eap_aka_build_challenge(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ u8 id)
+{
+ struct eap_sim_msg *msg;
+
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Challenge");
+ msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
+ EAP_AKA_SUBTYPE_CHALLENGE);
+ wpa_printf(MSG_DEBUG, " AT_RAND");
+ eap_sim_msg_add(msg, EAP_SIM_AT_RAND, 0, data->rand, EAP_AKA_RAND_LEN);
+ wpa_printf(MSG_DEBUG, " AT_AUTN");
+ eap_sim_msg_add(msg, EAP_SIM_AT_AUTN, 0, data->autn, EAP_AKA_AUTN_LEN);
+ if (data->eap_method == EAP_TYPE_AKA_PRIME) {
+ if (data->kdf) {
+ /* Add the selected KDF into the beginning */
+ wpa_printf(MSG_DEBUG, " AT_KDF");
+ eap_sim_msg_add(msg, EAP_SIM_AT_KDF, data->kdf,
+ NULL, 0);
+ }
+ wpa_printf(MSG_DEBUG, " AT_KDF");
+ eap_sim_msg_add(msg, EAP_SIM_AT_KDF, EAP_AKA_PRIME_KDF,
+ NULL, 0);
+ wpa_printf(MSG_DEBUG, " AT_KDF_INPUT");
+ eap_sim_msg_add(msg, EAP_SIM_AT_KDF_INPUT,
+ data->network_name_len,
+ data->network_name, data->network_name_len);
+ }
+
+ if (eap_aka_build_encr(sm, data, msg, 0, NULL)) {
+ eap_sim_msg_free(msg);
+ return NULL;
+ }
+
+ eap_aka_add_checkcode(data, msg);
+
+ if (sm->eap_sim_aka_result_ind) {
+ wpa_printf(MSG_DEBUG, " AT_RESULT_IND");
+ eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
+ }
+
+#ifdef EAP_SERVER_AKA_PRIME
+ if (data->eap_method == EAP_TYPE_AKA) {
+ u16 flags = 0;
+ int i;
+ int aka_prime_preferred = 0;
+
+ i = 0;
+ while (sm->user && i < EAP_MAX_METHODS &&
+ (sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
+ sm->user->methods[i].method != EAP_TYPE_NONE)) {
+ if (sm->user->methods[i].vendor == EAP_VENDOR_IETF) {
+ if (sm->user->methods[i].method ==
+ EAP_TYPE_AKA)
+ break;
+ if (sm->user->methods[i].method ==
+ EAP_TYPE_AKA_PRIME) {
+ aka_prime_preferred = 1;
+ break;
+ }
+ }
+ i++;
+ }
+
+ if (aka_prime_preferred)
+ flags |= EAP_AKA_BIDDING_FLAG_D;
+ eap_sim_msg_add(msg, EAP_SIM_AT_BIDDING, flags, NULL, 0);
+ }
+#endif /* EAP_SERVER_AKA_PRIME */
+
+ wpa_printf(MSG_DEBUG, " AT_MAC");
+ eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
+ return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
+}
+
+
+static struct wpabuf * eap_aka_build_reauth(struct eap_sm *sm,
+ struct eap_aka_data *data, u8 id)
+{
+ struct eap_sim_msg *msg;
+
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Re-authentication");
+
+ if (os_get_random(data->nonce_s, EAP_SIM_NONCE_S_LEN))
+ return NULL;
+ wpa_hexdump_key(MSG_MSGDUMP, "EAP-AKA: NONCE_S",
+ data->nonce_s, EAP_SIM_NONCE_S_LEN);
+
+ if (data->eap_method == EAP_TYPE_AKA_PRIME) {
+ eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
+ sm->identity,
+ sm->identity_len,
+ data->nonce_s,
+ data->msk, data->emsk);
+ } else {
+ eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
+ data->msk, data->emsk);
+ eap_sim_derive_keys_reauth(data->counter, sm->identity,
+ sm->identity_len, data->nonce_s,
+ data->mk, data->msk, data->emsk);
+ }
+
+ msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
+ EAP_AKA_SUBTYPE_REAUTHENTICATION);
+
+ if (eap_aka_build_encr(sm, data, msg, data->counter, data->nonce_s)) {
+ eap_sim_msg_free(msg);
+ return NULL;
+ }
+
+ eap_aka_add_checkcode(data, msg);
+
+ if (sm->eap_sim_aka_result_ind) {
+ wpa_printf(MSG_DEBUG, " AT_RESULT_IND");
+ eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
+ }
+
+ wpa_printf(MSG_DEBUG, " AT_MAC");
+ eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
+ return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
+}
+
+
+static struct wpabuf * eap_aka_build_notification(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ u8 id)
+{
+ struct eap_sim_msg *msg;
+
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Notification");
+ msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
+ EAP_AKA_SUBTYPE_NOTIFICATION);
+ wpa_printf(MSG_DEBUG, " AT_NOTIFICATION (%d)", data->notification);
+ eap_sim_msg_add(msg, EAP_SIM_AT_NOTIFICATION, data->notification,
+ NULL, 0);
+ if (data->use_result_ind) {
+ if (data->reauth) {
+ wpa_printf(MSG_DEBUG, " AT_IV");
+ wpa_printf(MSG_DEBUG, " AT_ENCR_DATA");
+ eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
+ EAP_SIM_AT_ENCR_DATA);
+ wpa_printf(MSG_DEBUG, " *AT_COUNTER (%u)",
+ data->counter);
+ eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
+ NULL, 0);
+
+ if (eap_sim_msg_add_encr_end(msg, data->k_encr,
+ EAP_SIM_AT_PADDING)) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Failed to "
+ "encrypt AT_ENCR_DATA");
+ eap_sim_msg_free(msg);
+ return NULL;
+ }
+ }
+
+ wpa_printf(MSG_DEBUG, " AT_MAC");
+ eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
+ }
+ return eap_sim_msg_finish(msg, data->k_aut, NULL, 0);
+}
+
+
+static struct wpabuf * eap_aka_buildReq(struct eap_sm *sm, void *priv, u8 id)
+{
+ struct eap_aka_data *data = priv;
+
+ data->auts_reported = 0;
+ switch (data->state) {
+ case IDENTITY:
+ return eap_aka_build_identity(sm, data, id);
+ case CHALLENGE:
+ return eap_aka_build_challenge(sm, data, id);
+ case REAUTH:
+ return eap_aka_build_reauth(sm, data, id);
+ case NOTIFICATION:
+ return eap_aka_build_notification(sm, data, id);
+ default:
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown state %d in "
+ "buildReq", data->state);
+ break;
+ }
+ return NULL;
+}
+
+
+static Boolean eap_aka_check(struct eap_sm *sm, void *priv,
+ struct wpabuf *respData)
+{
+ struct eap_aka_data *data = priv;
+ const u8 *pos;
+ size_t len;
+
+ pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, respData,
+ &len);
+ if (pos == NULL || len < 3) {
+ wpa_printf(MSG_INFO, "EAP-AKA: Invalid frame");
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+
+static Boolean eap_aka_subtype_ok(struct eap_aka_data *data, u8 subtype)
+{
+ if (subtype == EAP_AKA_SUBTYPE_CLIENT_ERROR ||
+ subtype == EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT)
+ return FALSE;
+
+ switch (data->state) {
+ case IDENTITY:
+ if (subtype != EAP_AKA_SUBTYPE_IDENTITY) {
+ wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
+ "subtype %d", subtype);
+ return TRUE;
+ }
+ break;
+ case CHALLENGE:
+ if (subtype != EAP_AKA_SUBTYPE_CHALLENGE &&
+ subtype != EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE) {
+ wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
+ "subtype %d", subtype);
+ return TRUE;
+ }
+ break;
+ case REAUTH:
+ if (subtype != EAP_AKA_SUBTYPE_REAUTHENTICATION) {
+ wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
+ "subtype %d", subtype);
+ return TRUE;
+ }
+ break;
+ case NOTIFICATION:
+ if (subtype != EAP_AKA_SUBTYPE_NOTIFICATION) {
+ wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
+ "subtype %d", subtype);
+ return TRUE;
+ }
+ break;
+ default:
+ wpa_printf(MSG_INFO, "EAP-AKA: Unexpected state (%d) for "
+ "processing a response", data->state);
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+
+static void eap_aka_determine_identity(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ int before_identity, int after_reauth)
+{
+ const u8 *identity;
+ size_t identity_len;
+ int res;
+
+ identity = NULL;
+ identity_len = 0;
+
+ if (after_reauth && data->reauth) {
+ identity = data->reauth->identity;
+ identity_len = data->reauth->identity_len;
+ } else if (sm->identity && sm->identity_len > 0 &&
+ sm->identity[0] == EAP_AKA_PERMANENT_PREFIX) {
+ identity = sm->identity;
+ identity_len = sm->identity_len;
+ } else {
+ identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv,
+ sm->identity,
+ sm->identity_len,
+ &identity_len);
+ if (identity == NULL) {
+ data->reauth = eap_sim_db_get_reauth_entry(
+ sm->eap_sim_db_priv, sm->identity,
+ sm->identity_len);
+ if (data->reauth &&
+ data->reauth->aka_prime !=
+ (data->eap_method == EAP_TYPE_AKA_PRIME)) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Reauth data "
+ "was for different AKA version");
+ data->reauth = NULL;
+ }
+ if (data->reauth) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Using fast "
+ "re-authentication");
+ identity = data->reauth->identity;
+ identity_len = data->reauth->identity_len;
+ data->counter = data->reauth->counter;
+ if (data->eap_method == EAP_TYPE_AKA_PRIME) {
+ os_memcpy(data->k_encr,
+ data->reauth->k_encr,
+ EAP_SIM_K_ENCR_LEN);
+ os_memcpy(data->k_aut,
+ data->reauth->k_aut,
+ EAP_AKA_PRIME_K_AUT_LEN);
+ os_memcpy(data->k_re,
+ data->reauth->k_re,
+ EAP_AKA_PRIME_K_RE_LEN);
+ } else {
+ os_memcpy(data->mk, data->reauth->mk,
+ EAP_SIM_MK_LEN);
+ }
+ }
+ }
+ }
+
+ if (identity == NULL ||
+ eap_sim_db_identity_known(sm->eap_sim_db_priv, sm->identity,
+ sm->identity_len) < 0) {
+ if (before_identity) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Permanent user name "
+ "not known - send AKA-Identity request");
+ eap_aka_state(data, IDENTITY);
+ return;
+ } else {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown whether the "
+ "permanent user name is known; try to use "
+ "it");
+ /* eap_sim_db_get_aka_auth() will report failure, if
+ * this identity is not known. */
+ }
+ }
+
+ wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Identity",
+ identity, identity_len);
+
+ if (!after_reauth && data->reauth) {
+ eap_aka_state(data, REAUTH);
+ return;
+ }
+
+ res = eap_sim_db_get_aka_auth(sm->eap_sim_db_priv, identity,
+ identity_len, data->rand, data->autn,
+ data->ik, data->ck, data->res,
+ &data->res_len, sm);
+ if (res == EAP_SIM_DB_PENDING) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: AKA authentication data "
+ "not yet available - pending request");
+ sm->method_pending = METHOD_PENDING_WAIT;
+ return;
+ }
+
+#ifdef EAP_SERVER_AKA_PRIME
+ if (data->eap_method == EAP_TYPE_AKA_PRIME) {
+ /* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
+ * needed 6-octet SQN ^AK for CK',IK' derivation */
+ eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
+ data->autn,
+ data->network_name,
+ data->network_name_len);
+ }
+#endif /* EAP_SERVER_AKA_PRIME */
+
+ data->reauth = NULL;
+ data->counter = 0; /* reset re-auth counter since this is full auth */
+
+ if (res != 0) {
+ wpa_printf(MSG_INFO, "EAP-AKA: Failed to get AKA "
+ "authentication data for the peer");
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+ if (sm->method_pending == METHOD_PENDING_WAIT) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: AKA authentication data "
+ "available - abort pending wait");
+ sm->method_pending = METHOD_PENDING_NONE;
+ }
+
+ identity_len = sm->identity_len;
+ while (identity_len > 0 && sm->identity[identity_len - 1] == '\0') {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Workaround - drop last null "
+ "character from identity");
+ identity_len--;
+ }
+ wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Identity for MK derivation",
+ sm->identity, identity_len);
+
+ if (data->eap_method == EAP_TYPE_AKA_PRIME) {
+ eap_aka_prime_derive_keys(identity, identity_len, data->ik,
+ data->ck, data->k_encr, data->k_aut,
+ data->k_re, data->msk, data->emsk);
+ } else {
+ eap_aka_derive_mk(sm->identity, identity_len, data->ik,
+ data->ck, data->mk);
+ eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
+ data->msk, data->emsk);
+ }
+
+ eap_aka_state(data, CHALLENGE);
+}
+
+
+static void eap_aka_process_identity(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ struct wpabuf *respData,
+ struct eap_sim_attrs *attr)
+{
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Identity");
+
+ if (attr->mac || attr->iv || attr->encr_data) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Unexpected attribute "
+ "received in EAP-Response/AKA-Identity");
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+
+ if (attr->identity) {
+ os_free(sm->identity);
+ sm->identity = os_malloc(attr->identity_len);
+ if (sm->identity) {
+ os_memcpy(sm->identity, attr->identity,
+ attr->identity_len);
+ sm->identity_len = attr->identity_len;
+ }
+ }
+
+ eap_aka_determine_identity(sm, data, 0, 0);
+ if (eap_get_id(respData) == data->pending_id) {
+ data->pending_id = -1;
+ eap_aka_add_id_msg(data, respData);
+ }
+}
+
+
+static int eap_aka_verify_mac(struct eap_aka_data *data,
+ const struct wpabuf *req,
+ const u8 *mac, const u8 *extra,
+ size_t extra_len)
+{
+ if (data->eap_method == EAP_TYPE_AKA_PRIME)
+ return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
+ extra_len);
+ return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
+}
+
+
+static void eap_aka_process_challenge(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ struct wpabuf *respData,
+ struct eap_sim_attrs *attr)
+{
+ const u8 *identity;
+ size_t identity_len;
+
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Challenge");
+
+#ifdef EAP_SERVER_AKA_PRIME
+#if 0
+ /* KDF negotiation; to be enabled only after more than one KDF is
+ * supported */
+ if (data->eap_method == EAP_TYPE_AKA_PRIME &&
+ attr->kdf_count == 1 && attr->mac == NULL) {
+ if (attr->kdf[0] != EAP_AKA_PRIME_KDF) {
+ wpa_printf(MSG_WARNING, "EAP-AKA': Peer selected "
+ "unknown KDF");
+ data->notification =
+ EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+
+ data->kdf = attr->kdf[0];
+
+ /* Allow negotiation to continue with the selected KDF by
+ * sending another Challenge message */
+ wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
+ return;
+ }
+#endif
+#endif /* EAP_SERVER_AKA_PRIME */
+
+ if (attr->checkcode &&
+ eap_aka_verify_checkcode(data, attr->checkcode,
+ attr->checkcode_len)) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
+ "message");
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+ if (attr->mac == NULL ||
+ eap_aka_verify_mac(data, respData, attr->mac, NULL, 0)) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
+ "did not include valid AT_MAC");
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+
+ /*
+ * AT_RES is padded, so verify that there is enough room for RES and
+ * that the RES length in bits matches with the expected RES.
+ */
+ if (attr->res == NULL || attr->res_len < data->res_len ||
+ attr->res_len_bits != data->res_len * 8 ||
+ os_memcmp(attr->res, data->res, data->res_len) != 0) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message did not "
+ "include valid AT_RES (attr len=%lu, res len=%lu "
+ "bits, expected %lu bits)",
+ (unsigned long) attr->res_len,
+ (unsigned long) attr->res_len_bits,
+ (unsigned long) data->res_len * 8);
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Challenge response includes the "
+ "correct AT_MAC");
+ if (sm->eap_sim_aka_result_ind && attr->result_ind) {
+ data->use_result_ind = 1;
+ data->notification = EAP_SIM_SUCCESS;
+ eap_aka_state(data, NOTIFICATION);
+ } else
+ eap_aka_state(data, SUCCESS);
+
+ identity = eap_sim_db_get_permanent(sm->eap_sim_db_priv, sm->identity,
+ sm->identity_len, &identity_len);
+ if (identity == NULL) {
+ identity = sm->identity;
+ identity_len = sm->identity_len;
+ }
+
+ if (data->next_pseudonym) {
+ eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
+ identity_len,
+ data->next_pseudonym);
+ data->next_pseudonym = NULL;
+ }
+ if (data->next_reauth_id) {
+ if (data->eap_method == EAP_TYPE_AKA_PRIME) {
+#ifdef EAP_SERVER_AKA_PRIME
+ eap_sim_db_add_reauth_prime(sm->eap_sim_db_priv,
+ identity,
+ identity_len,
+ data->next_reauth_id,
+ data->counter + 1,
+ data->k_encr, data->k_aut,
+ data->k_re);
+#endif /* EAP_SERVER_AKA_PRIME */
+ } else {
+ eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
+ identity_len,
+ data->next_reauth_id,
+ data->counter + 1,
+ data->mk);
+ }
+ data->next_reauth_id = NULL;
+ }
+}
+
+
+static void eap_aka_process_sync_failure(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ struct wpabuf *respData,
+ struct eap_sim_attrs *attr)
+{
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Synchronization-Failure");
+
+ if (attr->auts == NULL) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Synchronization-Failure "
+ "message did not include valid AT_AUTS");
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+
+ /* Avoid re-reporting AUTS when processing pending EAP packet by
+ * maintaining a local flag stating whether this AUTS has already been
+ * reported. */
+ if (!data->auts_reported &&
+ eap_sim_db_resynchronize(sm->eap_sim_db_priv, sm->identity,
+ sm->identity_len, attr->auts,
+ data->rand)) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Resynchronization failed");
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+ data->auts_reported = 1;
+
+ /* Try again after resynchronization */
+ eap_aka_determine_identity(sm, data, 0, 0);
+}
+
+
+static void eap_aka_process_reauth(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ struct wpabuf *respData,
+ struct eap_sim_attrs *attr)
+{
+ struct eap_sim_attrs eattr;
+ u8 *decrypted = NULL;
+ const u8 *identity, *id2;
+ size_t identity_len, id2_len;
+
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Reauthentication");
+
+ if (attr->mac == NULL ||
+ eap_aka_verify_mac(data, respData, attr->mac, data->nonce_s,
+ EAP_SIM_NONCE_S_LEN)) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Re-authentication message "
+ "did not include valid AT_MAC");
+ goto fail;
+ }
+
+ if (attr->encr_data == NULL || attr->iv == NULL) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
+ "message did not include encrypted data");
+ goto fail;
+ }
+
+ decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
+ attr->encr_data_len, attr->iv, &eattr,
+ 0);
+ if (decrypted == NULL) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
+ "data from reauthentication message");
+ goto fail;
+ }
+
+ if (eattr.counter != data->counter) {
+ wpa_printf(MSG_WARNING, "EAP-AKA: Re-authentication message "
+ "used incorrect counter %u, expected %u",
+ eattr.counter, data->counter);
+ goto fail;
+ }
+ os_free(decrypted);
+ decrypted = NULL;
+
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Re-authentication response includes "
+ "the correct AT_MAC");
+
+ if (eattr.counter_too_small) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Re-authentication response "
+ "included AT_COUNTER_TOO_SMALL - starting full "
+ "authentication");
+ eap_aka_determine_identity(sm, data, 0, 1);
+ return;
+ }
+
+ if (sm->eap_sim_aka_result_ind && attr->result_ind) {
+ data->use_result_ind = 1;
+ data->notification = EAP_SIM_SUCCESS;
+ eap_aka_state(data, NOTIFICATION);
+ } else
+ eap_aka_state(data, SUCCESS);
+
+ if (data->reauth) {
+ identity = data->reauth->identity;
+ identity_len = data->reauth->identity_len;
+ } else {
+ identity = sm->identity;
+ identity_len = sm->identity_len;
+ }
+
+ id2 = eap_sim_db_get_permanent(sm->eap_sim_db_priv, identity,
+ identity_len, &id2_len);
+ if (id2) {
+ identity = id2;
+ identity_len = id2_len;
+ }
+
+ if (data->next_pseudonym) {
+ eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, identity,
+ identity_len, data->next_pseudonym);
+ data->next_pseudonym = NULL;
+ }
+ if (data->next_reauth_id) {
+ if (data->eap_method == EAP_TYPE_AKA_PRIME) {
+#ifdef EAP_SERVER_AKA_PRIME
+ eap_sim_db_add_reauth_prime(sm->eap_sim_db_priv,
+ identity,
+ identity_len,
+ data->next_reauth_id,
+ data->counter + 1,
+ data->k_encr, data->k_aut,
+ data->k_re);
+#endif /* EAP_SERVER_AKA_PRIME */
+ } else {
+ eap_sim_db_add_reauth(sm->eap_sim_db_priv, identity,
+ identity_len,
+ data->next_reauth_id,
+ data->counter + 1,
+ data->mk);
+ }
+ data->next_reauth_id = NULL;
+ } else {
+ eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
+ data->reauth = NULL;
+ }
+
+ return;
+
+fail:
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
+ data->reauth = NULL;
+ os_free(decrypted);
+}
+
+
+static void eap_aka_process_client_error(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ struct wpabuf *respData,
+ struct eap_sim_attrs *attr)
+{
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Client reported error %d",
+ attr->client_error_code);
+ if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
+ eap_aka_state(data, SUCCESS);
+ else
+ eap_aka_state(data, FAILURE);
+}
+
+
+static void eap_aka_process_authentication_reject(
+ struct eap_sm *sm, struct eap_aka_data *data,
+ struct wpabuf *respData, struct eap_sim_attrs *attr)
+{
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Client rejected authentication");
+ eap_aka_state(data, FAILURE);
+}
+
+
+static void eap_aka_process_notification(struct eap_sm *sm,
+ struct eap_aka_data *data,
+ struct wpabuf *respData,
+ struct eap_sim_attrs *attr)
+{
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Client replied to notification");
+ if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
+ eap_aka_state(data, SUCCESS);
+ else
+ eap_aka_state(data, FAILURE);
+}
+
+
+static void eap_aka_process(struct eap_sm *sm, void *priv,
+ struct wpabuf *respData)
+{
+ struct eap_aka_data *data = priv;
+ const u8 *pos, *end;
+ u8 subtype;
+ size_t len;
+ struct eap_sim_attrs attr;
+
+ pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, respData,
+ &len);
+ if (pos == NULL || len < 3)
+ return;
+
+ end = pos + len;
+ subtype = *pos;
+ pos += 3;
+
+ if (eap_aka_subtype_ok(data, subtype)) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized or unexpected "
+ "EAP-AKA Subtype in EAP Response");
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+
+ if (eap_sim_parse_attr(pos, end, &attr,
+ data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
+ 0)) {
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Failed to parse attributes");
+ data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
+ eap_aka_state(data, NOTIFICATION);
+ return;
+ }
+
+ if (subtype == EAP_AKA_SUBTYPE_CLIENT_ERROR) {
+ eap_aka_process_client_error(sm, data, respData, &attr);
+ return;
+ }
+
+ if (subtype == EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT) {
+ eap_aka_process_authentication_reject(sm, data, respData,
+ &attr);
+ return;
+ }
+
+ switch (data->state) {
+ case IDENTITY:
+ eap_aka_process_identity(sm, data, respData, &attr);
+ break;
+ case CHALLENGE:
+ if (subtype == EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE) {
+ eap_aka_process_sync_failure(sm, data, respData,
+ &attr);
+ } else {
+ eap_aka_process_challenge(sm, data, respData, &attr);
+ }
+ break;
+ case REAUTH:
+ eap_aka_process_reauth(sm, data, respData, &attr);
+ break;
+ case NOTIFICATION:
+ eap_aka_process_notification(sm, data, respData, &attr);
+ break;
+ default:
+ wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown state %d in "
+ "process", data->state);
+ break;
+ }
+}
+
+
+static Boolean eap_aka_isDone(struct eap_sm *sm, void *priv)
+{
+ struct eap_aka_data *data = priv;
+ return data->state == SUCCESS || data->state == FAILURE;
+}
+
+
+static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
+{
+ struct eap_aka_data *data = priv;
+ u8 *key;
+
+ if (data->state != SUCCESS)
+ return NULL;
+
+ key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
+ if (key == NULL)
+ return NULL;
+ os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
+ *len = EAP_SIM_KEYING_DATA_LEN;
+ return key;
+}
+
+
+static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
+{
+ struct eap_aka_data *data = priv;
+ u8 *key;
+
+ if (data->state != SUCCESS)
+ return NULL;
+
+ key = os_malloc(EAP_EMSK_LEN);
+ if (key == NULL)
+ return NULL;
+ os_memcpy(key, data->emsk, EAP_EMSK_LEN);
+ *len = EAP_EMSK_LEN;
+ return key;
+}
+
+
+static Boolean eap_aka_isSuccess(struct eap_sm *sm, void *priv)
+{
+ struct eap_aka_data *data = priv;
+ return data->state == SUCCESS;
+}
+
+
+int eap_server_aka_register(void)
+{
+ struct eap_method *eap;
+ int ret;
+
+ eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
+ EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
+ if (eap == NULL)
+ return -1;
+
+ eap->init = eap_aka_init;
+ eap->reset = eap_aka_reset;
+ eap->buildReq = eap_aka_buildReq;
+ eap->check = eap_aka_check;
+ eap->process = eap_aka_process;
+ eap->isDone = eap_aka_isDone;
+ eap->getKey = eap_aka_getKey;
+ eap->isSuccess = eap_aka_isSuccess;
+ eap->get_emsk = eap_aka_get_emsk;
+
+ ret = eap_server_method_register(eap);
+ if (ret)
+ eap_server_method_free(eap);
+ return ret;
+}
+
+
+#ifdef EAP_SERVER_AKA_PRIME
+int eap_server_aka_prime_register(void)
+{
+ struct eap_method *eap;
+ int ret;
+
+ eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
+ EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
+ "AKA'");
+ if (eap == NULL)
+ return -1;
+
+ eap->init = eap_aka_prime_init;
+ eap->reset = eap_aka_reset;
+ eap->buildReq = eap_aka_buildReq;
+ eap->check = eap_aka_check;
+ eap->process = eap_aka_process;
+ eap->isDone = eap_aka_isDone;
+ eap->getKey = eap_aka_getKey;
+ eap->isSuccess = eap_aka_isSuccess;
+ eap->get_emsk = eap_aka_get_emsk;
+
+ ret = eap_server_method_register(eap);
+ if (ret)
+ eap_server_method_free(eap);
+
+ return ret;
+}
+#endif /* EAP_SERVER_AKA_PRIME */
projects / mech_eap.git / blobdiff