static u8 * eap_sim_process_challenge(struct eap_sm *sm, struct eap_sim_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; struct eap_sim_attrs eattr; wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Challenge"); data->reauth = 0; if (!attr->mac || !attr->rand) { wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message " "did not include%s%s", !attr->mac ? " AT_MAC" : "", !attr->rand ? " AT_RAND" : ""); return eap_sim_client_error(sm, data, req, respDataLen, EAP_SIM_UNABLE_TO_PROCESS_PACKET); } wpa_printf(MSG_DEBUG, "EAP-SIM: %lu challenges", (unsigned long) attr->num_chal); if (attr->num_chal < data->min_num_chal) { wpa_printf(MSG_INFO, "EAP-SIM: Insufficient number of " "challenges (%lu)", (unsigned long) attr->num_chal); return eap_sim_client_error(sm, data, req, respDataLen, EAP_SIM_INSUFFICIENT_NUM_OF_CHAL); } if (attr->num_chal > 3) { wpa_printf(MSG_INFO, "EAP-SIM: Too many challenges " "(%lu)", (unsigned long) attr->num_chal); return eap_sim_client_error(sm, data, req, respDataLen, EAP_SIM_UNABLE_TO_PROCESS_PACKET); } /* Verify that RANDs are different */ if (memcmp(attr->rand, attr->rand + GSM_RAND_LEN, GSM_RAND_LEN) == 0 || (attr->num_chal > 2 && (memcmp(attr->rand, attr->rand + 2 * GSM_RAND_LEN, GSM_RAND_LEN) == 0 || memcmp(attr->rand + GSM_RAND_LEN, attr->rand + 2 * GSM_RAND_LEN, GSM_RAND_LEN) == 0))) { wpa_printf(MSG_INFO, "EAP-SIM: Same RAND used multiple times"); return eap_sim_client_error(sm, data, req, respDataLen, EAP_SIM_RAND_NOT_FRESH); } memcpy(data->rand, attr->rand, attr->num_chal * GSM_RAND_LEN); data->num_chal = attr->num_chal; if (eap_sim_gsm_auth(sm, data)) { wpa_printf(MSG_WARNING, "EAP-SIM: GSM authentication failed"); return eap_sim_client_error(sm, data, req, respDataLen, EAP_SIM_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-SIM: Selected identity for MK " "derivation", identity, identity_len); eap_sim_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, data->nonce_mt, EAP_SIM_NONCE_MT_LEN)) { wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message " "used invalid AT_MAC"); return eap_sim_client_error(sm, data, req, respDataLen, EAP_SIM_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_sim_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_sim_client_error( sm, data, req, respDataLen, EAP_SIM_UNABLE_TO_PROCESS_PACKET); } eap_sim_learn_ids(data, &eattr); } if (data->state != FAILURE) data->state = SUCCESS; data->num_id_req = 0; data->num_notification = 0; /* draft-haverinen-pppext-eap-sim-13.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_sim_response_challenge(sm, data, req, respDataLen); }
static struct wpabuf * eap_sim_process_challenge(struct eap_sm *sm, struct eap_sim_data *data, u8 id, const struct wpabuf *reqData, struct eap_sim_attrs *attr) { const u8 *identity; size_t identity_len; struct eap_sim_attrs eattr; wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Challenge"); data->reauth = 0; if (!attr->mac || !attr->rand) { wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message " "did not include%s%s", !attr->mac ? " AT_MAC" : "", !attr->rand ? " AT_RAND" : ""); return eap_sim_client_error(data, id, EAP_SIM_UNABLE_TO_PROCESS_PACKET); } wpa_printf(MSG_DEBUG, "EAP-SIM: %lu challenges", (unsigned long) attr->num_chal); if (attr->num_chal < data->min_num_chal) { wpa_printf(MSG_INFO, "EAP-SIM: Insufficient number of " "challenges (%lu)", (unsigned long) attr->num_chal); return eap_sim_client_error(data, id, EAP_SIM_INSUFFICIENT_NUM_OF_CHAL); } if (attr->num_chal > 3) { wpa_printf(MSG_INFO, "EAP-SIM: Too many challenges " "(%lu)", (unsigned long) attr->num_chal); return eap_sim_client_error(data, id, EAP_SIM_UNABLE_TO_PROCESS_PACKET); } /* Verify that RANDs are different */ if (os_memcmp(attr->rand, attr->rand + GSM_RAND_LEN, GSM_RAND_LEN) == 0 || (attr->num_chal > 2 && (os_memcmp(attr->rand, attr->rand + 2 * GSM_RAND_LEN, GSM_RAND_LEN) == 0 || os_memcmp(attr->rand + GSM_RAND_LEN, attr->rand + 2 * GSM_RAND_LEN, GSM_RAND_LEN) == 0))) { wpa_printf(MSG_INFO, "EAP-SIM: Same RAND used multiple times"); return eap_sim_client_error(data, id, EAP_SIM_RAND_NOT_FRESH); } os_memcpy(data->rand, attr->rand, attr->num_chal * GSM_RAND_LEN); data->num_chal = attr->num_chal; if (eap_sim_gsm_auth(sm, data)) { wpa_printf(MSG_WARNING, "EAP-SIM: GSM authentication failed"); return eap_sim_client_error(data, id, EAP_SIM_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 = eap_get_config_identity(sm, &identity_len); wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Selected identity for MK " "derivation", identity, identity_len); eap_sim_derive_mk(identity, identity_len, data->nonce_mt, data->selected_version, data->ver_list, data->ver_list_len, data->num_chal, (const u8 *) data->kc, data->mk); eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk, data->emsk); if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, data->nonce_mt, EAP_SIM_NONCE_MT_LEN)) { wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message " "used invalid AT_MAC"); return eap_sim_client_error(data, id, EAP_SIM_UNABLE_TO_PROCESS_PACKET); } /* Old reauthentication identity must not be used anymore. In * other words, if no new reauth identity is received, full * authentication will be used on next reauthentication (using * pseudonym identity or permanent identity). */ eap_sim_clear_identities(data, CLEAR_REAUTH_ID | CLEAR_EAP_ID); if (attr->encr_data) { u8 *decrypted; decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data, attr->encr_data_len, attr->iv, &eattr, 0); if (decrypted == NULL) { return eap_sim_client_error( data, id, EAP_SIM_UNABLE_TO_PROCESS_PACKET); } eap_sim_learn_ids(sm, data, &eattr); os_free(decrypted); } if (data->result_ind && attr->result_ind) data->use_result_ind = 1; if (data->state != FAILURE && data->state != RESULT_FAILURE) { eap_sim_state(data, data->use_result_ind ? RESULT_SUCCESS : SUCCESS); } data->num_id_req = 0; data->num_notification = 0; /* RFC 4186 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_sim_response_challenge(data, id); }