diff options
Diffstat (limited to 'contrib/wpa_supplicant/eap_aka.c')
| -rw-r--r-- | contrib/wpa_supplicant/eap_aka.c | 915 |
1 files changed, 915 insertions, 0 deletions
diff --git a/contrib/wpa_supplicant/eap_aka.c b/contrib/wpa_supplicant/eap_aka.c new file mode 100644 index 0000000..7fe6449 --- /dev/null +++ b/contrib/wpa_supplicant/eap_aka.c @@ -0,0 +1,915 @@ +/* + * WPA Supplicant / EAP-AKA (draft-arkko-pppext-eap-aka-12.txt) + * Copyright (c) 2004-2005, Jouni Malinen <jkmaline@cc.hut.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 <stdlib.h> +#include <stdio.h> +#include <string.h> + +#include "common.h" +#include "eap_i.h" +#include "wpa_supplicant.h" +#include "config_ssid.h" +#include "sha1.h" +#include "pcsc_funcs.h" +#include "eap_sim_common.h" + +/* EAP-AKA Subtypes */ +#define EAP_AKA_SUBTYPE_CHALLENGE 1 +#define EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT 2 +#define EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE 4 +#define EAP_AKA_SUBTYPE_IDENTITY 5 +#define EAP_AKA_SUBTYPE_NOTIFICATION 12 +#define EAP_AKA_SUBTYPE_REAUTHENTICATION 13 +#define EAP_AKA_SUBTYPE_CLIENT_ERROR 14 + +/* AT_CLIENT_ERROR_CODE error codes */ +#define EAP_AKA_UNABLE_TO_PROCESS_PACKET 0 + +#define AKA_AUTS_LEN 14 +#define RES_MAX_LEN 16 +#define IK_LEN 16 +#define CK_LEN 16 +#define EAP_AKA_MAX_FAST_REAUTHS 1000 + +struct eap_aka_data { + u8 ik[IK_LEN], ck[CK_LEN], res[RES_MAX_LEN]; + size_t res_len; + u8 nonce_s[EAP_SIM_NONCE_S_LEN]; + u8 mk[EAP_SIM_MK_LEN]; + u8 k_aut[EAP_SIM_K_AUT_LEN]; + u8 k_encr[EAP_SIM_K_ENCR_LEN]; + u8 msk[EAP_SIM_KEYING_DATA_LEN]; + u8 rand[AKA_RAND_LEN], autn[AKA_AUTN_LEN]; + u8 auts[AKA_AUTS_LEN]; + + int num_id_req, num_notification; + u8 *pseudonym; + size_t pseudonym_len; + u8 *reauth_id; + size_t reauth_id_len; + int reauth; + unsigned int counter, counter_too_small; + u8 *last_eap_identity; + size_t last_eap_identity_len; + enum { CONTINUE, SUCCESS, FAILURE } state; +}; + + +static void * eap_aka_init(struct eap_sm *sm) +{ + struct eap_aka_data *data; + data = malloc(sizeof(*data)); + if (data == NULL) + return NULL; + memset(data, 0, sizeof(*data)); + + data->state = CONTINUE; + + return data; +} + + +static void eap_aka_deinit(struct eap_sm *sm, void *priv) +{ + struct eap_aka_data *data = priv; + if (data) { + free(data->pseudonym); + free(data->reauth_id); + free(data->last_eap_identity); + free(data); + } +} + + +static int eap_aka_umts_auth(struct eap_sm *sm, struct eap_aka_data *data) +{ + wpa_printf(MSG_DEBUG, "EAP-AKA: UMTS authentication algorithm"); +#ifdef PCSC_FUNCS + return scard_umts_auth(sm->scard_ctx, data->rand, + data->autn, data->res, &data->res_len, + data->ik, data->ck, data->auts); +#else /* PCSC_FUNCS */ + /* These hardcoded Kc and SRES values are used for testing. + * Could consider making them configurable. */ + memset(data->res, '2', RES_MAX_LEN); + data->res_len = 16; + memset(data->ik, '3', IK_LEN); + memset(data->ck, '4', CK_LEN); + { + u8 autn[AKA_AUTN_LEN]; + memset(autn, '1', AKA_AUTN_LEN); + if (memcmp(autn, data->autn, AKA_AUTN_LEN) != 0) { + wpa_printf(MSG_WARNING, "EAP-AKA: AUTN did not match " + "with expected value"); + return -1; + } + } + return 0; +#endif /* PCSC_FUNCS */ +} + + +static void eap_aka_derive_mk(struct eap_aka_data *data, + const u8 *identity, size_t identity_len) +{ + const u8 *addr[3]; + size_t len[3]; + + addr[0] = identity; + len[0] = identity_len; + addr[1] = data->ik; + len[1] = IK_LEN; + addr[2] = data->ck; + len[2] = CK_LEN; + + /* MK = SHA1(Identity|IK|CK) */ + sha1_vector(3, addr, len, data->mk); + wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", data->ik, IK_LEN); + wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", data->ck, CK_LEN); + wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: MK", data->mk, EAP_SIM_MK_LEN); +} + + +#define CLEAR_PSEUDONYM 0x01 +#define CLEAR_REAUTH_ID 0x02 +#define CLEAR_EAP_ID 0x04 + +static void eap_aka_clear_identities(struct eap_aka_data *data, int id) +{ + wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old%s%s%s", + id & CLEAR_PSEUDONYM ? " pseudonym" : "", + id & CLEAR_REAUTH_ID ? " reauth_id" : "", + id & CLEAR_EAP_ID ? " eap_id" : ""); + if (id & CLEAR_PSEUDONYM) { + free(data->pseudonym); + data->pseudonym = NULL; + data->pseudonym_len = 0; + } + if (id & CLEAR_REAUTH_ID) { + free(data->reauth_id); + data->reauth_id = NULL; + data->reauth_id_len = 0; + } + if (id & CLEAR_EAP_ID) { + free(data->last_eap_identity); + data->last_eap_identity = NULL; + data->last_eap_identity_len = 0; + } +} + + +static int eap_aka_learn_ids(struct eap_aka_data *data, + struct eap_sim_attrs *attr) +{ + if (attr->next_pseudonym) { + free(data->pseudonym); + data->pseudonym = malloc(attr->next_pseudonym_len); + if (data->pseudonym == NULL) { + wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for " + "next pseudonym"); + return -1; + } + memcpy(data->pseudonym, attr->next_pseudonym, + attr->next_pseudonym_len); + data->pseudonym_len = attr->next_pseudonym_len; + wpa_hexdump_ascii(MSG_DEBUG, + "EAP-AKA: (encr) AT_NEXT_PSEUDONYM", + data->pseudonym, + data->pseudonym_len); + } + + if (attr->next_reauth_id) { + free(data->reauth_id); + data->reauth_id = malloc(attr->next_reauth_id_len); + if (data->reauth_id == NULL) { + wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for " + "next reauth_id"); + return -1; + } + memcpy(data->reauth_id, attr->next_reauth_id, + attr->next_reauth_id_len); + data->reauth_id_len = attr->next_reauth_id_len; + wpa_hexdump_ascii(MSG_DEBUG, + "EAP-AKA: (encr) AT_NEXT_REAUTH_ID", + data->reauth_id, + data->reauth_id_len); + } + + return 0; +} + + +static u8 * eap_aka_client_error(struct eap_sm *sm, struct eap_aka_data *data, + struct eap_hdr *req, + size_t *respDataLen, int err) +{ + struct eap_sim_msg *msg; + + data->state = FAILURE; + data->num_id_req = 0; + data->num_notification = 0; + + msg = eap_sim_msg_init(EAP_CODE_RESPONSE, req->identifier, + EAP_TYPE_AKA, EAP_AKA_SUBTYPE_CLIENT_ERROR); + eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0); + return eap_sim_msg_finish(msg, respDataLen, NULL, NULL, 0); +} + + +static u8 * eap_aka_authentication_reject(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, + size_t *respDataLen) +{ + struct eap_sim_msg *msg; + + data->state = FAILURE; + data->num_id_req = 0; + data->num_notification = 0; + + wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject " + "(id=%d)", req->identifier); + msg = eap_sim_msg_init(EAP_CODE_RESPONSE, req->identifier, + EAP_TYPE_AKA, + EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT); + return eap_sim_msg_finish(msg, respDataLen, NULL, NULL, 0); +} + + +static u8 * eap_aka_synchronization_failure(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, + size_t *respDataLen) +{ + struct eap_sim_msg *msg; + + data->state = FAILURE; + data->num_id_req = 0; + data->num_notification = 0; + + wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure " + "(id=%d)", req->identifier); + msg = eap_sim_msg_init(EAP_CODE_RESPONSE, req->identifier, + EAP_TYPE_AKA, + EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE); + wpa_printf(MSG_DEBUG, " AT_AUTS"); + eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts, AKA_AUTS_LEN); + return eap_sim_msg_finish(msg, respDataLen, NULL, NULL, 0); +} + + +static u8 * eap_aka_response_identity(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, + size_t *respDataLen, + enum eap_sim_id_req id_req) +{ + struct wpa_ssid *config = eap_get_config(sm); + u8 *identity = NULL; + size_t identity_len = 0; + struct eap_sim_msg *msg; + + data->reauth = 0; + if (id_req == ANY_ID && data->reauth_id) { + identity = data->reauth_id; + identity_len = data->reauth_id_len; + data->reauth = 1; + } else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) && + data->pseudonym) { + identity = data->pseudonym; + identity_len = data->pseudonym_len; + eap_aka_clear_identities(data, CLEAR_REAUTH_ID); + } else if (id_req != NO_ID_REQ && config && config->identity) { + identity = config->identity; + identity_len = config->identity_len; + eap_aka_clear_identities(data, + CLEAR_PSEUDONYM | CLEAR_REAUTH_ID); + } + if (id_req != NO_ID_REQ) + eap_aka_clear_identities(data, CLEAR_EAP_ID); + + wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", + req->identifier); + msg = eap_sim_msg_init(EAP_CODE_RESPONSE, req->identifier, + EAP_TYPE_AKA, EAP_AKA_SUBTYPE_IDENTITY); + + if (identity) { + wpa_hexdump_ascii(MSG_DEBUG, " AT_IDENTITY", + identity, identity_len); + eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len, + identity, identity_len); + } + + return eap_sim_msg_finish(msg, respDataLen, NULL, NULL, 0); +} + + +static u8 * eap_aka_response_challenge(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, + size_t *respDataLen) +{ + struct eap_sim_msg *msg; + + wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", + req->identifier); + msg = eap_sim_msg_init(EAP_CODE_RESPONSE, req->identifier, + EAP_TYPE_AKA, EAP_AKA_SUBTYPE_CHALLENGE); + wpa_printf(MSG_DEBUG, " AT_RES"); + eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len, + data->res, data->res_len); + wpa_printf(MSG_DEBUG, " AT_MAC"); + eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC); + return eap_sim_msg_finish(msg, respDataLen, data->k_aut, (u8 *) "", 0); +} + + +static u8 * eap_aka_response_reauth(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, + size_t *respDataLen, int counter_too_small) +{ + struct eap_sim_msg *msg; + unsigned int counter; + + wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)", + req->identifier); + msg = eap_sim_msg_init(EAP_CODE_RESPONSE, req->identifier, + EAP_TYPE_AKA, + EAP_AKA_SUBTYPE_REAUTHENTICATION); + 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_too_small) { + wpa_printf(MSG_DEBUG, " *AT_COUNTER_TOO_SMALL"); + eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0); + counter = data->counter_too_small; + } else + counter = data->counter; + + wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", counter); + eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, 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, respDataLen, data->k_aut, data->nonce_s, + EAP_SIM_NONCE_S_LEN); +} + + +static u8 * eap_aka_response_notification(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, + size_t *respDataLen, + u16 notification) +{ + struct eap_sim_msg *msg; + u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL; + + wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", + req->identifier); + msg = eap_sim_msg_init(EAP_CODE_RESPONSE, req->identifier, + EAP_TYPE_AKA, EAP_AKA_SUBTYPE_NOTIFICATION); + wpa_printf(MSG_DEBUG, " AT_NOTIFICATION"); + eap_sim_msg_add(msg, EAP_SIM_AT_NOTIFICATION, notification, NULL, 0); + if (k_aut && 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 %d", 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; + } + } + if (k_aut) { + wpa_printf(MSG_DEBUG, " AT_MAC"); + eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC); + } + return eap_sim_msg_finish(msg, respDataLen, k_aut, (u8 *) "", 0); +} + + +static u8 * eap_aka_process_identity(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, size_t reqDataLen, + size_t *respDataLen, + struct eap_sim_attrs *attr) +{ + int id_error; + + wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity"); + + id_error = 0; + switch (attr->id_req) { + case NO_ID_REQ: + break; + case ANY_ID: + if (data->num_id_req > 0) + id_error++; + data->num_id_req++; + break; + case FULLAUTH_ID: + if (data->num_id_req > 1) + id_error++; + data->num_id_req++; + break; + case PERMANENT_ID: + if (data->num_id_req > 2) + id_error++; + data->num_id_req++; + break; + } + if (id_error) { + wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests " + "used within one authentication"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + return eap_aka_response_identity(sm, data, req, respDataLen, + attr->id_req); +} + + +static u8 * eap_aka_process_challenge(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, size_t reqDataLen, + size_t *respDataLen, + struct eap_sim_attrs *attr) +{ + struct wpa_ssid *config = eap_get_config(sm); + u8 *identity; + size_t identity_len; + int res; + struct eap_sim_attrs eattr; + + wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge"); + data->reauth = 0; + if (!attr->mac || !attr->rand || !attr->autn) { + wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message " + "did not include%s%s%s", + !attr->mac ? " AT_MAC" : "", + !attr->rand ? " AT_RAND" : "", + !attr->autn ? " AT_AUTN" : ""); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + memcpy(data->rand, attr->rand, AKA_RAND_LEN); + memcpy(data->autn, attr->autn, AKA_AUTN_LEN); + + res = eap_aka_umts_auth(sm, data); + if (res == -1) { + wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication " + "failed (AUTN)"); + return eap_aka_authentication_reject(sm, data, req, + respDataLen); + } else if (res == -2) { + wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication " + "failed (AUTN seq# -> AUTS)"); + return eap_aka_synchronization_failure(sm, data, req, + respDataLen); + } else if (res) { + wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + if (data->last_eap_identity) { + identity = data->last_eap_identity; + identity_len = data->last_eap_identity_len; + } else if (data->pseudonym) { + identity = data->pseudonym; + identity_len = data->pseudonym_len; + } else { + identity = config->identity; + identity_len = config->identity_len; + } + wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK " + "derivation", identity, identity_len); + eap_aka_derive_mk(data, identity, identity_len); + eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk); + if (eap_sim_verify_mac(data->k_aut, (u8 *) req, reqDataLen, attr->mac, + (u8 *) "", 0)) { + wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message " + "used invalid AT_MAC"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + /* Old reauthentication and pseudonym identities must not be used + * anymore. In other words, if no new identities are received, full + * authentication will be used on next reauthentication. */ + eap_aka_clear_identities(data, CLEAR_PSEUDONYM | CLEAR_REAUTH_ID | + CLEAR_EAP_ID); + + if (attr->encr_data) { + if (eap_sim_parse_encr(data->k_encr, attr->encr_data, + attr->encr_data_len, attr->iv, &eattr, + 0)) { + return eap_aka_client_error( + sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + eap_aka_learn_ids(data, &eattr); + } + + if (data->state != FAILURE) + data->state = SUCCESS; + + data->num_id_req = 0; + data->num_notification = 0; + /* draft-arkko-pppext-eap-aka-12.txt specifies that counter + * is initialized to one after fullauth, but initializing it to + * zero makes it easier to implement reauth verification. */ + data->counter = 0; + return eap_aka_response_challenge(sm, data, req, respDataLen); +} + + +static int eap_aka_process_notification_reauth(struct eap_aka_data *data, + struct eap_hdr *req, + size_t reqDataLen, + struct eap_sim_attrs *attr) +{ + struct eap_sim_attrs eattr; + + if (attr->encr_data == NULL || attr->iv == NULL) { + wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after " + "reauth did not include encrypted data"); + return -1; + } + + if (eap_sim_parse_encr(data->k_encr, attr->encr_data, + attr->encr_data_len, attr->iv, &eattr, 0)) { + wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted " + "data from notification message"); + return -1; + } + + if (eattr.counter != data->counter) { + wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification " + "message does not match with counter in reauth " + "message"); + return -1; + } + + return 0; +} + + +static int eap_aka_process_notification_auth(struct eap_aka_data *data, + struct eap_hdr *req, + size_t reqDataLen, + struct eap_sim_attrs *attr) +{ + if (attr->mac == NULL) { + wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth " + "Notification message"); + return -1; + } + + if (eap_sim_verify_mac(data->k_aut, (u8 *) req, reqDataLen, attr->mac, + (u8 *) "", 0)) { + wpa_printf(MSG_WARNING, "EAP-AKA: Notification message " + "used invalid AT_MAC"); + return -1; + } + + if (data->reauth && + eap_aka_process_notification_reauth(data, req, reqDataLen, attr)) { + wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification " + "message after reauth"); + return -1; + } + + return 0; +} + + +static u8 * eap_aka_process_notification(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, + size_t reqDataLen, + size_t *respDataLen, + struct eap_sim_attrs *attr) +{ + wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification"); + if (data->num_notification > 0) { + wpa_printf(MSG_INFO, "EAP-AKA: too many notification " + "rounds (only one allowed)"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + data->num_notification++; + if (attr->notification == -1) { + wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in " + "Notification message"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + if ((attr->notification & 0x4000) == 0 && + eap_aka_process_notification_auth(data, req, reqDataLen, attr)) { + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + eap_sim_report_notification(sm->msg_ctx, attr->notification, 1); + if (attr->notification >= 0 && attr->notification < 32768) { + data->state = FAILURE; + } + return eap_aka_response_notification(sm, data, req, respDataLen, + attr->notification); +} + + +static u8 * eap_aka_process_reauthentication(struct eap_sm *sm, + struct eap_aka_data *data, + struct eap_hdr *req, + size_t reqDataLen, + size_t *respDataLen, + struct eap_sim_attrs *attr) +{ + struct eap_sim_attrs eattr; + + wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication"); + + if (data->reauth_id == NULL) { + wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying " + "reauthentication, but no reauth_id available"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + data->reauth = 1; + if (eap_sim_verify_mac(data->k_aut, (u8 *) req, reqDataLen, + attr->mac, (u8 *) "", 0)) { + wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication " + "did not have valid AT_MAC"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + if (attr->encr_data == NULL || attr->iv == NULL) { + wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication " + "message did not include encrypted data"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + if (eap_sim_parse_encr(data->k_encr, attr->encr_data, + attr->encr_data_len, attr->iv, &eattr, 0)) { + wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted " + "data from reauthentication message"); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + if (eattr.nonce_s == NULL || eattr.counter < 0) { + wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet", + !eattr.nonce_s ? " AT_NONCE_S" : "", + eattr.counter < 0 ? " AT_COUNTER" : ""); + return eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + } + + if (eattr.counter <= data->counter) { + wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter " + "(%d <= %d)", eattr.counter, data->counter); + data->counter_too_small = eattr.counter; + /* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current + * reauth_id must not be used to start a new reauthentication. + * However, since it was used in the last EAP-Response-Identity + * packet, it has to saved for the following fullauth to be + * used in MK derivation. */ + free(data->last_eap_identity); + data->last_eap_identity = data->reauth_id; + data->last_eap_identity_len = data->reauth_id_len; + data->reauth_id = NULL; + data->reauth_id_len = 0; + return eap_aka_response_reauth(sm, data, req, respDataLen, 1); + } + data->counter = eattr.counter; + + memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN); + wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S", + data->nonce_s, EAP_SIM_NONCE_S_LEN); + + eap_sim_derive_keys_reauth(data->counter, + data->reauth_id, data->reauth_id_len, + data->nonce_s, data->mk, data->msk); + eap_aka_clear_identities(data, CLEAR_REAUTH_ID | CLEAR_EAP_ID); + eap_aka_learn_ids(data, &eattr); + + if (data->state != FAILURE) + data->state = SUCCESS; + + data->num_id_req = 0; + data->num_notification = 0; + if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) { + wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of " + "fast reauths performed - force fullauth"); + eap_aka_clear_identities(data, CLEAR_REAUTH_ID | CLEAR_EAP_ID); + } + return eap_aka_response_reauth(sm, data, req, respDataLen, 0); +} + + +static u8 * eap_aka_process(struct eap_sm *sm, void *priv, + struct eap_method_ret *ret, + u8 *reqData, size_t reqDataLen, + size_t *respDataLen) +{ + struct eap_aka_data *data = priv; + struct wpa_ssid *config = eap_get_config(sm); + struct eap_hdr *req; + u8 *pos, subtype, *res; + struct eap_sim_attrs attr; + size_t len; + + wpa_hexdump(MSG_DEBUG, "EAP-AKA: EAP data", reqData, reqDataLen); + if (config == NULL || config->identity == NULL) { + wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured"); + eap_sm_request_identity(sm, config); + ret->ignore = TRUE; + return NULL; + } + + req = (struct eap_hdr *) reqData; + pos = (u8 *) (req + 1); + if (reqDataLen < sizeof(*req) + 4 || *pos != EAP_TYPE_AKA || + (len = be_to_host16(req->length)) > reqDataLen) { + wpa_printf(MSG_INFO, "EAP-AKA: Invalid frame"); + ret->ignore = TRUE; + return NULL; + } + + ret->ignore = FALSE; + ret->methodState = METHOD_CONT; + ret->decision = DECISION_FAIL; + ret->allowNotifications = TRUE; + + pos++; + subtype = *pos++; + wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype); + pos += 2; /* Reserved */ + + if (eap_sim_parse_attr(pos, reqData + len, &attr, 1, 0)) { + res = eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + goto done; + } + + switch (subtype) { + case EAP_AKA_SUBTYPE_IDENTITY: + res = eap_aka_process_identity(sm, data, req, len, + respDataLen, &attr); + break; + case EAP_AKA_SUBTYPE_CHALLENGE: + res = eap_aka_process_challenge(sm, data, req, len, + respDataLen, &attr); + break; + case EAP_AKA_SUBTYPE_NOTIFICATION: + res = eap_aka_process_notification(sm, data, req, len, + respDataLen, &attr); + break; + case EAP_AKA_SUBTYPE_REAUTHENTICATION: + res = eap_aka_process_reauthentication(sm, data, req, len, + respDataLen, &attr); + break; + case EAP_AKA_SUBTYPE_CLIENT_ERROR: + wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error"); + res = eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + break; + default: + wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype); + res = eap_aka_client_error(sm, data, req, respDataLen, + EAP_AKA_UNABLE_TO_PROCESS_PACKET); + break; + } + +done: + if (data->state == FAILURE) { + ret->decision = DECISION_FAIL; + ret->methodState = METHOD_DONE; + } else if (data->state == SUCCESS) { + ret->decision = DECISION_UNCOND_SUCC; + ret->methodState = METHOD_DONE; + } + + if (ret->methodState == METHOD_DONE) { + ret->allowNotifications = FALSE; + } + + return res; +} + + +static Boolean eap_aka_has_reauth_data(struct eap_sm *sm, void *priv) +{ + struct eap_aka_data *data = priv; + return data->pseudonym || data->reauth_id; +} + + +static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv) +{ + struct eap_aka_data *data = priv; + eap_aka_clear_identities(data, CLEAR_EAP_ID); +} + + +static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv) +{ + struct eap_aka_data *data = priv; + data->num_id_req = 0; + data->num_notification = 0; + data->state = CONTINUE; + return priv; +} + + +static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv, + size_t *len) +{ + struct eap_aka_data *data = priv; + + if (data->reauth_id) { + *len = data->reauth_id_len; + return data->reauth_id; + } + + if (data->pseudonym) { + *len = data->pseudonym_len; + return data->pseudonym; + } + + return NULL; +} + + +static Boolean eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv) +{ + struct eap_aka_data *data = priv; + return data->state == SUCCESS; +} + + +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 = malloc(EAP_SIM_KEYING_DATA_LEN); + if (key == NULL) + return NULL; + + *len = EAP_SIM_KEYING_DATA_LEN; + memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN); + + return key; +} + + +const struct eap_method eap_method_aka = +{ + .method = EAP_TYPE_AKA, + .name = "AKA", + .init = eap_aka_init, + .deinit = eap_aka_deinit, + .process = eap_aka_process, + .isKeyAvailable = eap_aka_isKeyAvailable, + .getKey = eap_aka_getKey, + .has_reauth_data = eap_aka_has_reauth_data, + .deinit_for_reauth = eap_aka_deinit_for_reauth, + .init_for_reauth = eap_aka_init_for_reauth, + .get_identity = eap_aka_get_identity, +}; 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