EAP-pwd: Add support for EAP-pwd server and peer functionality
This adds an initial EAP-pwd (RFC 5931) implementation. For now, this requires OpenSSL.
This commit is contained in:
Dan Harkins
Jouni Malinen
parent
ea184114ca
commit
df684d82ff
23 changed files with 2038 additions and 0 deletions
730
src/eap_peer/eap_pwd.c
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730
src/eap_peer/eap_pwd.c
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@ -0,0 +1,730 @@
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/*
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* EAP peer method: EAP-pwd (RFC 5931)
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* Copyright (c) 2010, Dan Harkins <dharkins@lounge.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the BSD license.
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*
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* Alternatively, this software may be distributed under the terms of the
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* GNU General Public License version 2 as published by the Free Software
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* Foundation.
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*
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* See README and COPYING for more details.
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*/
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#include "includes.h"
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#include "common.h"
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#include "eap_peer/eap_i.h"
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#include "eap_common/eap_pwd_common.h"
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struct eap_pwd_data {
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enum {
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PWD_ID_Req, PWD_Commit_Req, PWD_Confirm_Req, SUCCESS, FAILURE
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} state;
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u8 *id_peer;
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size_t id_peer_len;
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u8 *id_server;
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size_t id_server_len;
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u8 *password;
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size_t password_len;
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u16 group_num;
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EAP_PWD_group *grp;
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BIGNUM *k;
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BIGNUM *private_value;
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BIGNUM *server_scalar;
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BIGNUM *my_scalar;
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EC_POINT *my_element;
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EC_POINT *server_element;
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u8 msk[EAP_MSK_LEN];
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u8 emsk[EAP_EMSK_LEN];
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};
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static BN_CTX *bnctx;
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#ifndef CONFIG_NO_STDOUT_DEBUG
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static const char * eap_pwd_state_txt(int state)
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{
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switch (state) {
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case PWD_ID_Req:
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return "PWD-ID-Req";
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case PWD_Commit_Req:
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return "PWD-Commit-Req";
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case PWD_Confirm_Req:
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return "PWD-Confirm-Req";
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case SUCCESS:
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return "SUCCESS";
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case FAILURE:
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return "FAILURE";
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default:
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return "PWD-UNK";
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}
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}
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#endif /* CONFIG_NO_STDOUT_DEBUG */
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static void eap_pwd_state(struct eap_pwd_data *data, int state)
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{
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wpa_printf(MSG_INFO, "EAP-PWD: %s -> %s",
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eap_pwd_state_txt(data->state), eap_pwd_state_txt(state));
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data->state = state;
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}
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static void * eap_pwd_init(struct eap_sm *sm)
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{
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struct eap_pwd_data *data;
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const u8 *identity, *password;
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size_t identity_len, password_len;
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password = eap_get_config_password(sm, &password_len);
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if (password == NULL) {
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wpa_printf(MSG_INFO, "EAP-PWD: No password configured!");
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return NULL;
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}
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identity = eap_get_config_identity(sm, &identity_len);
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if (identity == NULL) {
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wpa_printf(MSG_INFO, "EAP-PWD: No identity configured!");
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return NULL;
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}
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if ((bnctx = BN_CTX_new()) == NULL) {
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wpa_printf(MSG_INFO, "EAP-PWD: bn context allocation fail");
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return NULL;
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}
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if ((data = os_zalloc(sizeof(*data))) == NULL) {
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wpa_printf(MSG_INFO, "EAP-PWD: memory allocation data fail");
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return NULL;
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}
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if ((data->id_peer = os_malloc(identity_len)) == NULL) {
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wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
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os_free(data);
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return NULL;
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}
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os_memcpy(data->id_peer, identity, identity_len);
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data->id_peer_len = identity_len;
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if ((data->password = os_malloc(password_len)) == NULL) {
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wpa_printf(MSG_INFO, "EAP-PWD: memory allocation psk fail");
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os_free(data->id_peer);
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os_free(data);
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return NULL;
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}
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os_memcpy(data->password, password, password_len);
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data->password_len = password_len;
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data->state = PWD_ID_Req;
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return data;
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}
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static void eap_pwd_deinit(struct eap_sm *sm, void *priv)
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{
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struct eap_pwd_data *data = priv;
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BN_free(data->private_value);
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BN_free(data->server_scalar);
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BN_free(data->my_scalar);
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BN_free(data->k);
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BN_CTX_free(bnctx);
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EC_POINT_free(data->my_element);
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EC_POINT_free(data->server_element);
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os_free(data->id_peer);
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os_free(data->password);
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os_free(data->grp);
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os_free(data);
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}
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static u8 * eap_pwd_getkey(struct eap_sm *sm, void *priv, size_t *len)
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{
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struct eap_pwd_data *data = priv;
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u8 *key;
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if (data->state != SUCCESS)
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return NULL;
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key = os_malloc(EAP_MSK_LEN);
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if (key == NULL)
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return NULL;
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os_memcpy(key, data->msk, EAP_MSK_LEN);
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*len = EAP_MSK_LEN;
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return key;
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}
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static struct wpabuf *
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eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
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struct eap_method_ret *ret,
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const struct wpabuf *reqData,
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const u8 *payload, size_t payload_len)
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{
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struct eap_pwd_id *id;
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struct wpabuf *resp;
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if (data->state != PWD_ID_Req) {
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ret->ignore = TRUE;
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return NULL;
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}
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if (payload_len < sizeof(struct eap_pwd_id)) {
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ret->ignore = TRUE;
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return NULL;
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}
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id = (struct eap_pwd_id *) payload;
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data->group_num = be_to_host16(id->group_num);
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if ((id->random_function != EAP_PWD_DEFAULT_RAND_FUNC) ||
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(id->prf != EAP_PWD_DEFAULT_PRF)) {
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ret->ignore = TRUE;
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return NULL;
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}
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wpa_printf(MSG_DEBUG, "EAP-PWD (peer): server said group %d",
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data->group_num);
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data->id_server = os_malloc(payload_len - sizeof(struct eap_pwd_id));
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if (data->id_server == NULL) {
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wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
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return NULL;
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}
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data->id_server_len = payload_len - sizeof(struct eap_pwd_id);
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os_memcpy(data->id_server, id->identity, data->id_server_len);
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wpa_hexdump_ascii(MSG_INFO, "EAP-PWD (peer): server sent id of",
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data->id_server, data->id_server_len);
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if ((data->grp = (EAP_PWD_group *) os_malloc(sizeof(EAP_PWD_group))) ==
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NULL) {
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wpa_printf(MSG_INFO, "EAP-PWD: failed to allocate memory for "
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"group");
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return NULL;
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}
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/* compute PWE */
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if (compute_password_element(data->grp, data->group_num,
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data->password, data->password_len,
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data->id_server, data->id_server_len,
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data->id_peer, data->id_peer_len,
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id->token)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute PWE");
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return NULL;
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}
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wpa_printf(MSG_INFO, "EAP-PWD (peer): computed %d bit PWE...",
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BN_num_bits(data->grp->prime));
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resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
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1 + sizeof(struct eap_pwd_id) + data->id_peer_len,
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EAP_CODE_RESPONSE, eap_get_id(reqData));
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if (resp == NULL)
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return NULL;
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wpabuf_put_u8(resp, EAP_PWD_OPCODE_ID_EXCH);
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wpabuf_put_be16(resp, data->group_num);
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wpabuf_put_u8(resp, EAP_PWD_DEFAULT_RAND_FUNC);
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wpabuf_put_u8(resp, EAP_PWD_DEFAULT_PRF);
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wpabuf_put_data(resp, id->token, sizeof(id->token));
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wpabuf_put_u8(resp, EAP_PWD_PREP_NONE);
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wpabuf_put_data(resp, data->id_peer, data->id_peer_len);
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eap_pwd_state(data, PWD_Commit_Req);
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return resp;
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}
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static struct wpabuf *
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eap_pwd_perform_commit_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
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struct eap_method_ret *ret,
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const struct wpabuf *reqData,
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const u8 *payload, size_t payload_len)
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{
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struct wpabuf *resp = NULL;
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EC_POINT *K = NULL, *point = NULL;
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BIGNUM *mask = NULL, *x = NULL, *y = NULL, *cofactor = NULL;
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u16 offset;
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u8 *ptr, *scalar = NULL, *element = NULL;
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if (((data->private_value = BN_new()) == NULL) ||
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((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
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((cofactor = BN_new()) == NULL) ||
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((data->my_scalar = BN_new()) == NULL) ||
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((mask = BN_new()) == NULL)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): scalar allocation fail");
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goto fin;
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}
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if (!EC_GROUP_get_cofactor(data->grp->group, cofactor, NULL)) {
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wpa_printf(MSG_INFO, "EAP-pwd (peer): unable to get cofactor "
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"for curve");
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goto fin;
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}
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BN_rand_range(data->private_value, data->grp->order);
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BN_rand_range(mask, data->grp->order);
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BN_add(data->my_scalar, data->private_value, mask);
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BN_mod(data->my_scalar, data->my_scalar, data->grp->order, bnctx);
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if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
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data->grp->pwe, mask, bnctx)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): element allocation "
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"fail");
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eap_pwd_state(data, FAILURE);
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goto fin;
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}
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if (!EC_POINT_invert(data->grp->group, data->my_element, bnctx)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): element inversion fail");
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goto fin;
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}
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BN_free(mask);
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if (((x = BN_new()) == NULL) ||
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((y = BN_new()) == NULL)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): point allocation fail");
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goto fin;
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}
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/* process the request */
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if (((data->server_scalar = BN_new()) == NULL) ||
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((data->k = BN_new()) == NULL) ||
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((K = EC_POINT_new(data->grp->group)) == NULL) ||
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((point = EC_POINT_new(data->grp->group)) == NULL) ||
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((data->server_element = EC_POINT_new(data->grp->group)) == NULL))
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{
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wpa_printf(MSG_INFO, "EAP-PWD (peer): peer data allocation "
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"fail");
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goto fin;
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}
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/* element, x then y, followed by scalar */
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ptr = (u8 *) payload;
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BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), x);
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ptr += BN_num_bytes(data->grp->prime);
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BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), y);
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ptr += BN_num_bytes(data->grp->prime);
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BN_bin2bn(ptr, BN_num_bytes(data->grp->order), data->server_scalar);
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if (!EC_POINT_set_affine_coordinates_GFp(data->grp->group,
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data->server_element, x, y,
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bnctx)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): setting peer element "
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"fail");
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goto fin;
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}
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/* check to ensure server's element is not in a small sub-group */
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if (BN_cmp(cofactor, BN_value_one())) {
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if (!EC_POINT_mul(data->grp->group, point, NULL,
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data->server_element, cofactor, NULL)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
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"server element by order!\n");
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goto fin;
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}
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if (EC_POINT_is_at_infinity(data->grp->group, point)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): server element "
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"is at infinity!\n");
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goto fin;
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}
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}
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/* compute the shared key, k */
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if ((!EC_POINT_mul(data->grp->group, K, NULL, data->grp->pwe,
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data->server_scalar, bnctx)) ||
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(!EC_POINT_add(data->grp->group, K, K, data->server_element,
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bnctx)) ||
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(!EC_POINT_mul(data->grp->group, K, NULL, K, data->private_value,
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bnctx))) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): computing shared key "
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"fail");
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goto fin;
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}
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/* ensure that the shared key isn't in a small sub-group */
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if (BN_cmp(cofactor, BN_value_one())) {
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if (!EC_POINT_mul(data->grp->group, K, NULL, K, cofactor,
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NULL)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
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"shared key point by order");
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goto fin;
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}
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}
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/*
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* This check is strictly speaking just for the case above where
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* co-factor > 1 but it was suggested that even though this is probably
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* never going to happen it is a simple and safe check "just to be
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* sure" so let's be safe.
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*/
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if (EC_POINT_is_at_infinity(data->grp->group, K)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): shared key point is at "
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"infinity!\n");
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goto fin;
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}
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if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group, K, data->k,
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NULL, bnctx)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to extract "
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"shared secret from point");
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goto fin;
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}
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/* now do the response */
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if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
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data->my_element, x, y,
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bnctx)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): point assignment fail");
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goto fin;
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}
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if (((scalar = os_malloc(BN_num_bytes(data->grp->order))) == NULL) ||
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((element = os_malloc(BN_num_bytes(data->grp->prime) * 2)) ==
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NULL)) {
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wpa_printf(MSG_INFO, "EAP-PWD (peer): data allocation fail");
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goto fin;
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}
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/*
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* bignums occupy as little memory as possible so one that is
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* sufficiently smaller than the prime or order might need pre-pending
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* with zeros.
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*/
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os_memset(scalar, 0, BN_num_bytes(data->grp->order));
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os_memset(element, 0, BN_num_bytes(data->grp->prime) * 2);
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offset = BN_num_bytes(data->grp->order) -
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BN_num_bytes(data->my_scalar);
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BN_bn2bin(data->my_scalar, scalar + offset);
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offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
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BN_bn2bin(x, element + offset);
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offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
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BN_bn2bin(y, element + BN_num_bytes(data->grp->prime) + offset);
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resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
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sizeof(struct eap_pwd_hdr) +
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BN_num_bytes(data->grp->order) +
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(2 * BN_num_bytes(data->grp->prime)),
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EAP_CODE_RESPONSE, eap_get_id(reqData));
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if (resp == NULL)
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goto fin;
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wpabuf_put_u8(resp, EAP_PWD_OPCODE_COMMIT_EXCH);
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/* we send the element as (x,y) follwed by the scalar */
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wpabuf_put_data(resp, element, (2 * BN_num_bytes(data->grp->prime)));
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wpabuf_put_data(resp, scalar, BN_num_bytes(data->grp->order));
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fin:
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os_free(scalar);
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os_free(element);
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BN_free(x);
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BN_free(y);
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BN_free(cofactor);
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EC_POINT_free(K);
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EC_POINT_free(point);
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if (resp == NULL)
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eap_pwd_state(data, FAILURE);
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else
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eap_pwd_state(data, PWD_Confirm_Req);
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return resp;
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}
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static struct wpabuf *
|
||||
eap_pwd_perform_confirm_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
|
||||
struct eap_method_ret *ret,
|
||||
const struct wpabuf *reqData,
|
||||
const u8 *payload, size_t payload_len)
|
||||
{
|
||||
struct wpabuf *resp = NULL;
|
||||
BIGNUM *x = NULL, *y = NULL;
|
||||
HMAC_CTX ctx;
|
||||
u32 cs;
|
||||
u8 conf[SHA256_DIGEST_LENGTH], *cruft = NULL, *ptr;
|
||||
|
||||
/*
|
||||
* first build up the ciphersuite which is group | random_function |
|
||||
* prf
|
||||
*/
|
||||
ptr = (u8 *) &cs;
|
||||
os_memcpy(ptr, &data->group_num, sizeof(u16));
|
||||
ptr += sizeof(u16);
|
||||
*ptr = EAP_PWD_DEFAULT_RAND_FUNC;
|
||||
ptr += sizeof(u8);
|
||||
*ptr = EAP_PWD_DEFAULT_PRF;
|
||||
|
||||
/* each component of the cruft will be at most as big as the prime */
|
||||
if (((cruft = os_malloc(BN_num_bytes(data->grp->prime))) == NULL) ||
|
||||
((x = BN_new()) == NULL) || ((y = BN_new()) == NULL)) {
|
||||
wpa_printf(MSG_INFO, "EAP-PWD (server): debug allocation "
|
||||
"fail");
|
||||
goto fin;
|
||||
}
|
||||
|
||||
/*
|
||||
* server's commit is H(k | server_element | server_scalar |
|
||||
* peer_element | peer_scalar | ciphersuite)
|
||||
*/
|
||||
H_Init(&ctx);
|
||||
|
||||
/*
|
||||
* zero the memory each time because this is mod prime math and some
|
||||
* value may start with a few zeros and the previous one did not.
|
||||
*/
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(data->k, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
|
||||
/* server element: x, y */
|
||||
if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
|
||||
data->server_element, x, y,
|
||||
bnctx)) {
|
||||
wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
|
||||
"assignment fail");
|
||||
goto fin;
|
||||
}
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(x, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(y, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
|
||||
/* server scalar */
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(data->server_scalar, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
|
||||
|
||||
/* my element: x, y */
|
||||
if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
|
||||
data->my_element, x, y,
|
||||
bnctx)) {
|
||||
wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
|
||||
"assignment fail");
|
||||
goto fin;
|
||||
}
|
||||
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(x, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(y, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
|
||||
/* my scalar */
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(data->my_scalar, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
|
||||
|
||||
/* the ciphersuite */
|
||||
H_Update(&ctx, (u8 *) &cs, sizeof(u32));
|
||||
|
||||
/* random function fin */
|
||||
H_Final(&ctx, conf);
|
||||
|
||||
ptr = (u8 *) payload;
|
||||
if (os_memcmp(conf, ptr, SHA256_DIGEST_LENGTH)) {
|
||||
wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm did not verify");
|
||||
goto fin;
|
||||
}
|
||||
|
||||
wpa_printf(MSG_DEBUG, "EAP-pwd (peer): confirm verified");
|
||||
|
||||
/*
|
||||
* compute confirm:
|
||||
* H(k | peer_element | peer_scalar | server_element | server_scalar |
|
||||
* ciphersuite)
|
||||
*/
|
||||
H_Init(&ctx);
|
||||
|
||||
/* k */
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(data->k, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
|
||||
/* my element */
|
||||
if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
|
||||
data->my_element, x, y,
|
||||
bnctx)) {
|
||||
wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm point "
|
||||
"assignment fail");
|
||||
goto fin;
|
||||
}
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(x, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(y, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
|
||||
/* my scalar */
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(data->my_scalar, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
|
||||
|
||||
/* server element: x, y */
|
||||
if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
|
||||
data->server_element, x, y,
|
||||
bnctx)) {
|
||||
wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm point "
|
||||
"assignment fail");
|
||||
goto fin;
|
||||
}
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(x, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(y, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
|
||||
|
||||
/* server scalar */
|
||||
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
|
||||
BN_bn2bin(data->server_scalar, cruft);
|
||||
H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
|
||||
|
||||
/* the ciphersuite */
|
||||
H_Update(&ctx, (u8 *) &cs, sizeof(u32));
|
||||
|
||||
/* all done */
|
||||
H_Final(&ctx, conf);
|
||||
|
||||
resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
|
||||
sizeof(struct eap_pwd_hdr) + SHA256_DIGEST_LENGTH,
|
||||
EAP_CODE_RESPONSE, eap_get_id(reqData));
|
||||
if (resp == NULL)
|
||||
goto fin;
|
||||
|
||||
wpabuf_put_u8(resp, EAP_PWD_OPCODE_CONFIRM_EXCH);
|
||||
wpabuf_put_data(resp, conf, SHA256_DIGEST_LENGTH);
|
||||
|
||||
if (compute_keys(data->grp, bnctx, data->k, data->server_element,
|
||||
data->my_element, data->server_scalar,
|
||||
data->my_scalar, &cs, data->msk, data->emsk) < 0) {
|
||||
wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute MSK | "
|
||||
"EMSK");
|
||||
goto fin;
|
||||
}
|
||||
|
||||
fin:
|
||||
os_free(cruft);
|
||||
BN_free(x);
|
||||
BN_free(y);
|
||||
ret->methodState = METHOD_DONE;
|
||||
if (resp == NULL) {
|
||||
ret->decision = DECISION_FAIL;
|
||||
eap_pwd_state(data, FAILURE);
|
||||
} else {
|
||||
ret->decision = DECISION_UNCOND_SUCC;
|
||||
eap_pwd_state(data, SUCCESS);
|
||||
}
|
||||
|
||||
return resp;
|
||||
}
|
||||
|
||||
|
||||
static struct wpabuf *
|
||||
eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
|
||||
const struct wpabuf *reqData)
|
||||
{
|
||||
struct eap_pwd_data *data = priv;
|
||||
struct wpabuf *resp = NULL;
|
||||
const u8 *pos;
|
||||
size_t len;
|
||||
u8 exch;
|
||||
|
||||
pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PWD, reqData, &len);
|
||||
if ((pos == NULL) || (len < 1)) {
|
||||
ret->ignore = TRUE;
|
||||
return NULL;
|
||||
}
|
||||
|
||||
wpa_printf(MSG_INFO, "EAP-pwd: Received frame: opcode %d", *pos);
|
||||
|
||||
ret->ignore = FALSE;
|
||||
ret->methodState = METHOD_MAY_CONT;
|
||||
ret->decision = DECISION_FAIL;
|
||||
ret->allowNotifications = FALSE;
|
||||
|
||||
exch = *pos & 0x3f;
|
||||
switch (exch) {
|
||||
case EAP_PWD_OPCODE_ID_EXCH:
|
||||
resp = eap_pwd_perform_id_exchange(sm, data, ret, reqData,
|
||||
pos + 1, len - 1);
|
||||
break;
|
||||
case EAP_PWD_OPCODE_COMMIT_EXCH:
|
||||
resp = eap_pwd_perform_commit_exchange(sm, data, ret, reqData,
|
||||
pos + 1, len - 1);
|
||||
break;
|
||||
case EAP_PWD_OPCODE_CONFIRM_EXCH:
|
||||
resp = eap_pwd_perform_confirm_exchange(sm, data, ret, reqData,
|
||||
pos + 1, len - 1);
|
||||
break;
|
||||
default:
|
||||
wpa_printf(MSG_INFO, "EAP-pwd: Ignoring message with unknown "
|
||||
"opcode %d", exch);
|
||||
break;
|
||||
}
|
||||
|
||||
return resp;
|
||||
}
|
||||
|
||||
|
||||
static Boolean eap_pwd_key_available(struct eap_sm *sm, void *priv)
|
||||
{
|
||||
struct eap_pwd_data *data = priv;
|
||||
return data->state == SUCCESS;
|
||||
}
|
||||
|
||||
|
||||
static u8 * eap_pwd_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
|
||||
{
|
||||
struct eap_pwd_data *data = priv;
|
||||
u8 *key;
|
||||
|
||||
if (data->state != SUCCESS)
|
||||
return NULL;
|
||||
|
||||
if ((key = os_malloc(EAP_EMSK_LEN)) == NULL)
|
||||
return NULL;
|
||||
|
||||
os_memcpy(key, data->emsk, EAP_EMSK_LEN);
|
||||
*len = EAP_EMSK_LEN;
|
||||
|
||||
return key;
|
||||
}
|
||||
|
||||
|
||||
int eap_peer_pwd_register(void)
|
||||
{
|
||||
struct eap_method *eap;
|
||||
int ret;
|
||||
|
||||
EVP_add_digest(EVP_sha256());
|
||||
eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
|
||||
EAP_VENDOR_IETF, EAP_TYPE_PWD, "PWD");
|
||||
if (eap == NULL)
|
||||
return -1;
|
||||
|
||||
eap->init = eap_pwd_init;
|
||||
eap->deinit = eap_pwd_deinit;
|
||||
eap->process = eap_pwd_process;
|
||||
eap->isKeyAvailable = eap_pwd_key_available;
|
||||
eap->getKey = eap_pwd_getkey;
|
||||
eap->get_emsk = eap_pwd_get_emsk;
|
||||
|
||||
ret = eap_peer_method_register(eap);
|
||||
if (ret)
|
||||
eap_peer_method_free(eap);
|
||||
return ret;
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue