dddf7bbd4e
This makes the implementation less likely to provide useful timing information to potential attackers from comparisons of information received from a remote device and private material known only by the authorized devices. Signed-off-by: Jouni Malinen <j@w1.fi>
768 lines
18 KiB
C
768 lines
18 KiB
C
/*
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* EAP server/peer: EAP-EKE shared routines
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* Copyright (c) 2011-2013, Jouni Malinen <j@w1.fi>
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*
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* This software may be distributed under the terms of the BSD license.
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* See README 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 "crypto/aes.h"
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#include "crypto/aes_wrap.h"
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#include "crypto/crypto.h"
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#include "crypto/dh_groups.h"
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#include "crypto/random.h"
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#include "crypto/sha1.h"
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#include "crypto/sha256.h"
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#include "eap_common/eap_defs.h"
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#include "eap_eke_common.h"
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static int eap_eke_dh_len(u8 group)
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{
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switch (group) {
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case EAP_EKE_DHGROUP_EKE_2:
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return 128;
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case EAP_EKE_DHGROUP_EKE_5:
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return 192;
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case EAP_EKE_DHGROUP_EKE_14:
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return 256;
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case EAP_EKE_DHGROUP_EKE_15:
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return 384;
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case EAP_EKE_DHGROUP_EKE_16:
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return 512;
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}
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return -1;
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}
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static int eap_eke_dhcomp_len(u8 dhgroup, u8 encr)
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{
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int dhlen;
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dhlen = eap_eke_dh_len(dhgroup);
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if (dhlen < 0)
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return -1;
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if (encr != EAP_EKE_ENCR_AES128_CBC)
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return -1;
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return AES_BLOCK_SIZE + dhlen;
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}
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static const struct dh_group * eap_eke_dh_group(u8 group)
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{
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switch (group) {
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case EAP_EKE_DHGROUP_EKE_2:
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return dh_groups_get(2);
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case EAP_EKE_DHGROUP_EKE_5:
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return dh_groups_get(5);
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case EAP_EKE_DHGROUP_EKE_14:
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return dh_groups_get(14);
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case EAP_EKE_DHGROUP_EKE_15:
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return dh_groups_get(15);
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case EAP_EKE_DHGROUP_EKE_16:
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return dh_groups_get(16);
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}
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return NULL;
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}
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static int eap_eke_dh_generator(u8 group)
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{
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switch (group) {
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case EAP_EKE_DHGROUP_EKE_2:
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return 5;
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case EAP_EKE_DHGROUP_EKE_5:
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return 31;
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case EAP_EKE_DHGROUP_EKE_14:
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return 11;
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case EAP_EKE_DHGROUP_EKE_15:
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return 5;
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case EAP_EKE_DHGROUP_EKE_16:
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return 5;
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}
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return -1;
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}
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static int eap_eke_pnonce_len(u8 mac)
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{
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int mac_len;
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if (mac == EAP_EKE_MAC_HMAC_SHA1)
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mac_len = SHA1_MAC_LEN;
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else if (mac == EAP_EKE_MAC_HMAC_SHA2_256)
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mac_len = SHA256_MAC_LEN;
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else
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return -1;
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return AES_BLOCK_SIZE + 16 + mac_len;
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}
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static int eap_eke_pnonce_ps_len(u8 mac)
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{
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int mac_len;
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if (mac == EAP_EKE_MAC_HMAC_SHA1)
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mac_len = SHA1_MAC_LEN;
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else if (mac == EAP_EKE_MAC_HMAC_SHA2_256)
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mac_len = SHA256_MAC_LEN;
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else
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return -1;
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return AES_BLOCK_SIZE + 2 * 16 + mac_len;
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}
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static int eap_eke_prf_len(u8 prf)
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{
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if (prf == EAP_EKE_PRF_HMAC_SHA1)
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return 20;
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if (prf == EAP_EKE_PRF_HMAC_SHA2_256)
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return 32;
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return -1;
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}
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static int eap_eke_nonce_len(u8 prf)
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{
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int prf_len;
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prf_len = eap_eke_prf_len(prf);
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if (prf_len < 0)
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return -1;
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if (prf_len > 2 * 16)
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return (prf_len + 1) / 2;
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return 16;
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}
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static int eap_eke_auth_len(u8 prf)
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{
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switch (prf) {
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case EAP_EKE_PRF_HMAC_SHA1:
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return SHA1_MAC_LEN;
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case EAP_EKE_PRF_HMAC_SHA2_256:
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return SHA256_MAC_LEN;
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}
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return -1;
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}
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int eap_eke_dh_init(u8 group, u8 *ret_priv, u8 *ret_pub)
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{
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int generator;
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u8 gen;
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const struct dh_group *dh;
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size_t pub_len, i;
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generator = eap_eke_dh_generator(group);
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if (generator < 0 || generator > 255)
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return -1;
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gen = generator;
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dh = eap_eke_dh_group(group);
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if (dh == NULL)
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return -1;
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/* x = random number 2 .. p-1 */
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if (random_get_bytes(ret_priv, dh->prime_len))
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return -1;
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if (os_memcmp(ret_priv, dh->prime, dh->prime_len) > 0) {
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/* Make sure private value is smaller than prime */
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ret_priv[0] = 0;
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}
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for (i = 0; i < dh->prime_len - 1; i++) {
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if (ret_priv[i])
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break;
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}
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if (i == dh->prime_len - 1 && (ret_priv[i] == 0 || ret_priv[i] == 1))
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return -1;
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wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: DH private value",
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ret_priv, dh->prime_len);
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/* y = g ^ x (mod p) */
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pub_len = dh->prime_len;
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if (crypto_mod_exp(&gen, 1, ret_priv, dh->prime_len,
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dh->prime, dh->prime_len, ret_pub, &pub_len) < 0)
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return -1;
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if (pub_len < dh->prime_len) {
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size_t pad = dh->prime_len - pub_len;
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os_memmove(ret_pub + pad, ret_pub, pub_len);
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os_memset(ret_pub, 0, pad);
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}
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wpa_hexdump(MSG_DEBUG, "EAP-EKE: DH public value",
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ret_pub, dh->prime_len);
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return 0;
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}
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static int eap_eke_prf(u8 prf, const u8 *key, size_t key_len, const u8 *data,
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size_t data_len, const u8 *data2, size_t data2_len,
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u8 *res)
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{
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const u8 *addr[2];
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size_t len[2];
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size_t num_elem = 1;
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addr[0] = data;
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len[0] = data_len;
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if (data2) {
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num_elem++;
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addr[1] = data2;
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len[1] = data2_len;
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}
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if (prf == EAP_EKE_PRF_HMAC_SHA1)
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return hmac_sha1_vector(key, key_len, num_elem, addr, len, res);
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if (prf == EAP_EKE_PRF_HMAC_SHA2_256)
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return hmac_sha256_vector(key, key_len, num_elem, addr, len,
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res);
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return -1;
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}
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static int eap_eke_prf_hmac_sha1(const u8 *key, size_t key_len, const u8 *data,
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size_t data_len, u8 *res, size_t len)
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{
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u8 hash[SHA1_MAC_LEN];
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u8 idx;
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const u8 *addr[3];
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size_t vlen[3];
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int ret;
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idx = 0;
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addr[0] = hash;
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vlen[0] = SHA1_MAC_LEN;
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addr[1] = data;
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vlen[1] = data_len;
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addr[2] = &idx;
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vlen[2] = 1;
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while (len > 0) {
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idx++;
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if (idx == 1)
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ret = hmac_sha1_vector(key, key_len, 2, &addr[1],
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&vlen[1], hash);
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else
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ret = hmac_sha1_vector(key, key_len, 3, addr, vlen,
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hash);
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if (ret < 0)
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return -1;
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if (len > SHA1_MAC_LEN) {
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os_memcpy(res, hash, SHA1_MAC_LEN);
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res += SHA1_MAC_LEN;
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len -= SHA1_MAC_LEN;
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} else {
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os_memcpy(res, hash, len);
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len = 0;
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}
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}
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return 0;
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}
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static int eap_eke_prf_hmac_sha256(const u8 *key, size_t key_len, const u8 *data,
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size_t data_len, u8 *res, size_t len)
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{
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u8 hash[SHA256_MAC_LEN];
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u8 idx;
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const u8 *addr[3];
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size_t vlen[3];
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int ret;
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idx = 0;
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addr[0] = hash;
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vlen[0] = SHA256_MAC_LEN;
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addr[1] = data;
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vlen[1] = data_len;
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addr[2] = &idx;
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vlen[2] = 1;
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while (len > 0) {
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idx++;
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if (idx == 1)
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ret = hmac_sha256_vector(key, key_len, 2, &addr[1],
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&vlen[1], hash);
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else
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ret = hmac_sha256_vector(key, key_len, 3, addr, vlen,
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hash);
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if (ret < 0)
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return -1;
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if (len > SHA256_MAC_LEN) {
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os_memcpy(res, hash, SHA256_MAC_LEN);
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res += SHA256_MAC_LEN;
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len -= SHA256_MAC_LEN;
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} else {
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os_memcpy(res, hash, len);
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len = 0;
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}
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}
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return 0;
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}
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static int eap_eke_prfplus(u8 prf, const u8 *key, size_t key_len,
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const u8 *data, size_t data_len, u8 *res, size_t len)
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{
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if (prf == EAP_EKE_PRF_HMAC_SHA1)
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return eap_eke_prf_hmac_sha1(key, key_len, data, data_len, res,
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len);
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if (prf == EAP_EKE_PRF_HMAC_SHA2_256)
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return eap_eke_prf_hmac_sha256(key, key_len, data, data_len,
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res, len);
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return -1;
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}
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int eap_eke_derive_key(struct eap_eke_session *sess,
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const u8 *password, size_t password_len,
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const u8 *id_s, size_t id_s_len, const u8 *id_p,
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size_t id_p_len, u8 *key)
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{
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u8 zeros[EAP_EKE_MAX_HASH_LEN];
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u8 temp[EAP_EKE_MAX_HASH_LEN];
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size_t key_len = 16; /* Only AES-128-CBC is used here */
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u8 *id;
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/* temp = prf(0+, password) */
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os_memset(zeros, 0, sess->prf_len);
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if (eap_eke_prf(sess->prf, zeros, sess->prf_len,
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password, password_len, NULL, 0, temp) < 0)
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return -1;
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wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: temp = prf(0+, password)",
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temp, sess->prf_len);
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/* key = prf+(temp, ID_S | ID_P) */
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id = os_malloc(id_s_len + id_p_len);
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if (id == NULL)
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return -1;
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os_memcpy(id, id_s, id_s_len);
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os_memcpy(id + id_s_len, id_p, id_p_len);
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wpa_hexdump_ascii(MSG_DEBUG, "EAP-EKE: ID_S | ID_P",
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id, id_s_len + id_p_len);
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if (eap_eke_prfplus(sess->prf, temp, sess->prf_len,
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id, id_s_len + id_p_len, key, key_len) < 0) {
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os_free(id);
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return -1;
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}
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os_free(id);
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wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: key = prf+(temp, ID_S | ID_P)",
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key, key_len);
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return 0;
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}
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int eap_eke_dhcomp(struct eap_eke_session *sess, const u8 *key, const u8 *dhpub,
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u8 *ret_dhcomp)
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{
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u8 pub[EAP_EKE_MAX_DH_LEN];
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int dh_len;
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u8 iv[AES_BLOCK_SIZE];
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dh_len = eap_eke_dh_len(sess->dhgroup);
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if (dh_len < 0)
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return -1;
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/*
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* DHComponent = Encr(key, y)
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*
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* All defined DH groups use primes that have length devisible by 16, so
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* no need to do extra padding for y (= pub).
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*/
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if (sess->encr != EAP_EKE_ENCR_AES128_CBC)
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return -1;
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if (random_get_bytes(iv, AES_BLOCK_SIZE))
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return -1;
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wpa_hexdump(MSG_DEBUG, "EAP-EKE: IV for Encr(key, y)",
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iv, AES_BLOCK_SIZE);
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os_memcpy(pub, dhpub, dh_len);
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if (aes_128_cbc_encrypt(key, iv, pub, dh_len) < 0)
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return -1;
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os_memcpy(ret_dhcomp, iv, AES_BLOCK_SIZE);
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os_memcpy(ret_dhcomp + AES_BLOCK_SIZE, pub, dh_len);
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wpa_hexdump(MSG_DEBUG, "EAP-EKE: DHComponent = Encr(key, y)",
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ret_dhcomp, AES_BLOCK_SIZE + dh_len);
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return 0;
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}
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int eap_eke_shared_secret(struct eap_eke_session *sess, const u8 *key,
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const u8 *dhpriv, const u8 *peer_dhcomp)
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{
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u8 zeros[EAP_EKE_MAX_HASH_LEN];
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u8 peer_pub[EAP_EKE_MAX_DH_LEN];
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u8 modexp[EAP_EKE_MAX_DH_LEN];
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size_t len;
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const struct dh_group *dh;
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if (sess->encr != EAP_EKE_ENCR_AES128_CBC)
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return -1;
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dh = eap_eke_dh_group(sess->dhgroup);
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if (dh == NULL)
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return -1;
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/* Decrypt peer DHComponent */
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os_memcpy(peer_pub, peer_dhcomp + AES_BLOCK_SIZE, dh->prime_len);
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if (aes_128_cbc_decrypt(key, peer_dhcomp, peer_pub, dh->prime_len) < 0) {
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wpa_printf(MSG_INFO, "EAP-EKE: Failed to decrypt DHComponent");
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return -1;
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}
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wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Decrypted peer DH pubkey",
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peer_pub, dh->prime_len);
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/* SharedSecret = prf(0+, g ^ (x_s * x_p) (mod p)) */
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len = dh->prime_len;
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if (crypto_mod_exp(peer_pub, dh->prime_len, dhpriv, dh->prime_len,
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dh->prime, dh->prime_len, modexp, &len) < 0)
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return -1;
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if (len < dh->prime_len) {
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size_t pad = dh->prime_len - len;
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os_memmove(modexp + pad, modexp, len);
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os_memset(modexp, 0, pad);
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}
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os_memset(zeros, 0, sess->auth_len);
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if (eap_eke_prf(sess->prf, zeros, sess->auth_len, modexp, dh->prime_len,
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NULL, 0, sess->shared_secret) < 0)
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return -1;
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wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: SharedSecret",
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sess->shared_secret, sess->auth_len);
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return 0;
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}
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int eap_eke_derive_ke_ki(struct eap_eke_session *sess,
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const u8 *id_s, size_t id_s_len,
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const u8 *id_p, size_t id_p_len)
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{
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u8 buf[EAP_EKE_MAX_KE_LEN + EAP_EKE_MAX_KI_LEN];
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size_t ke_len, ki_len;
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u8 *data;
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size_t data_len;
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const char *label = "EAP-EKE Keys";
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size_t label_len;
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/*
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* Ke | Ki = prf+(SharedSecret, "EAP-EKE Keys" | ID_S | ID_P)
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* Ke = encryption key
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* Ki = integrity protection key
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* Length of each key depends on the selected algorithms.
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*/
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if (sess->encr == EAP_EKE_ENCR_AES128_CBC)
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ke_len = 16;
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else
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return -1;
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if (sess->mac == EAP_EKE_PRF_HMAC_SHA1)
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ki_len = 20;
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else if (sess->mac == EAP_EKE_PRF_HMAC_SHA2_256)
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ki_len = 32;
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else
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return -1;
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label_len = os_strlen(label);
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data_len = label_len + id_s_len + id_p_len;
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data = os_malloc(data_len);
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if (data == NULL)
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return -1;
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os_memcpy(data, label, label_len);
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os_memcpy(data + label_len, id_s, id_s_len);
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os_memcpy(data + label_len + id_s_len, id_p, id_p_len);
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if (eap_eke_prfplus(sess->prf, sess->shared_secret, sess->prf_len,
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data, data_len, buf, ke_len + ki_len) < 0) {
|
|
os_free(data);
|
|
return -1;
|
|
}
|
|
|
|
os_memcpy(sess->ke, buf, ke_len);
|
|
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Ke", sess->ke, ke_len);
|
|
os_memcpy(sess->ki, buf + ke_len, ki_len);
|
|
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Ki", sess->ki, ki_len);
|
|
|
|
os_free(data);
|
|
return 0;
|
|
}
|
|
|
|
|
|
int eap_eke_derive_ka(struct eap_eke_session *sess,
|
|
const u8 *id_s, size_t id_s_len,
|
|
const u8 *id_p, size_t id_p_len,
|
|
const u8 *nonce_p, const u8 *nonce_s)
|
|
{
|
|
u8 *data, *pos;
|
|
size_t data_len;
|
|
const char *label = "EAP-EKE Ka";
|
|
size_t label_len;
|
|
|
|
/*
|
|
* Ka = prf+(SharedSecret, "EAP-EKE Ka" | ID_S | ID_P | Nonce_P |
|
|
* Nonce_S)
|
|
* Ka = authentication key
|
|
* Length of the key depends on the selected algorithms.
|
|
*/
|
|
|
|
label_len = os_strlen(label);
|
|
data_len = label_len + id_s_len + id_p_len + 2 * sess->nonce_len;
|
|
data = os_malloc(data_len);
|
|
if (data == NULL)
|
|
return -1;
|
|
pos = data;
|
|
os_memcpy(pos, label, label_len);
|
|
pos += label_len;
|
|
os_memcpy(pos, id_s, id_s_len);
|
|
pos += id_s_len;
|
|
os_memcpy(pos, id_p, id_p_len);
|
|
pos += id_p_len;
|
|
os_memcpy(pos, nonce_p, sess->nonce_len);
|
|
pos += sess->nonce_len;
|
|
os_memcpy(pos, nonce_s, sess->nonce_len);
|
|
if (eap_eke_prfplus(sess->prf, sess->shared_secret, sess->prf_len,
|
|
data, data_len, sess->ka, sess->prf_len) < 0) {
|
|
os_free(data);
|
|
return -1;
|
|
}
|
|
os_free(data);
|
|
|
|
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Ka", sess->ka, sess->prf_len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
int eap_eke_derive_msk(struct eap_eke_session *sess,
|
|
const u8 *id_s, size_t id_s_len,
|
|
const u8 *id_p, size_t id_p_len,
|
|
const u8 *nonce_p, const u8 *nonce_s,
|
|
u8 *msk, u8 *emsk)
|
|
{
|
|
u8 *data, *pos;
|
|
size_t data_len;
|
|
const char *label = "EAP-EKE Exported Keys";
|
|
size_t label_len;
|
|
u8 buf[EAP_MSK_LEN + EAP_EMSK_LEN];
|
|
|
|
/*
|
|
* MSK | EMSK = prf+(SharedSecret, "EAP-EKE Exported Keys" | ID_S |
|
|
* ID_P | Nonce_P | Nonce_S)
|
|
*/
|
|
|
|
label_len = os_strlen(label);
|
|
data_len = label_len + id_s_len + id_p_len + 2 * sess->nonce_len;
|
|
data = os_malloc(data_len);
|
|
if (data == NULL)
|
|
return -1;
|
|
pos = data;
|
|
os_memcpy(pos, label, label_len);
|
|
pos += label_len;
|
|
os_memcpy(pos, id_s, id_s_len);
|
|
pos += id_s_len;
|
|
os_memcpy(pos, id_p, id_p_len);
|
|
pos += id_p_len;
|
|
os_memcpy(pos, nonce_p, sess->nonce_len);
|
|
pos += sess->nonce_len;
|
|
os_memcpy(pos, nonce_s, sess->nonce_len);
|
|
if (eap_eke_prfplus(sess->prf, sess->shared_secret, sess->prf_len,
|
|
data, data_len, buf, EAP_MSK_LEN + EAP_EMSK_LEN) <
|
|
0) {
|
|
os_free(data);
|
|
return -1;
|
|
}
|
|
os_free(data);
|
|
|
|
os_memcpy(msk, buf, EAP_MSK_LEN);
|
|
os_memcpy(emsk, buf + EAP_MSK_LEN, EAP_EMSK_LEN);
|
|
os_memset(buf, 0, sizeof(buf));
|
|
|
|
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: MSK", msk, EAP_MSK_LEN);
|
|
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: EMSK", msk, EAP_EMSK_LEN);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int eap_eke_mac(u8 mac, const u8 *key, const u8 *data, size_t data_len,
|
|
u8 *res)
|
|
{
|
|
if (mac == EAP_EKE_MAC_HMAC_SHA1)
|
|
return hmac_sha1(key, SHA1_MAC_LEN, data, data_len, res);
|
|
if (mac == EAP_EKE_MAC_HMAC_SHA2_256)
|
|
return hmac_sha256(key, SHA256_MAC_LEN, data, data_len, res);
|
|
return -1;
|
|
}
|
|
|
|
|
|
int eap_eke_prot(struct eap_eke_session *sess,
|
|
const u8 *data, size_t data_len,
|
|
u8 *prot, size_t *prot_len)
|
|
{
|
|
size_t block_size, icv_len, pad;
|
|
u8 *pos, *iv, *e;
|
|
|
|
if (sess->encr == EAP_EKE_ENCR_AES128_CBC)
|
|
block_size = AES_BLOCK_SIZE;
|
|
else
|
|
return -1;
|
|
|
|
if (sess->mac == EAP_EKE_PRF_HMAC_SHA1)
|
|
icv_len = SHA1_MAC_LEN;
|
|
else if (sess->mac == EAP_EKE_PRF_HMAC_SHA2_256)
|
|
icv_len = SHA256_MAC_LEN;
|
|
else
|
|
return -1;
|
|
|
|
pad = data_len % block_size;
|
|
if (pad)
|
|
pad = block_size - pad;
|
|
|
|
if (*prot_len < block_size + data_len + pad + icv_len) {
|
|
wpa_printf(MSG_INFO, "EAP-EKE: Not enough room for Prot() data");
|
|
}
|
|
pos = prot;
|
|
|
|
if (random_get_bytes(pos, block_size))
|
|
return -1;
|
|
iv = pos;
|
|
wpa_hexdump(MSG_DEBUG, "EAP-EKE: IV for Prot()", iv, block_size);
|
|
pos += block_size;
|
|
|
|
e = pos;
|
|
os_memcpy(pos, data, data_len);
|
|
pos += data_len;
|
|
if (pad) {
|
|
if (random_get_bytes(pos, pad))
|
|
return -1;
|
|
pos += pad;
|
|
}
|
|
|
|
if (aes_128_cbc_encrypt(sess->ke, iv, e, data_len + pad) < 0)
|
|
return -1;
|
|
|
|
if (eap_eke_mac(sess->mac, sess->ki, e, data_len + pad, pos) < 0)
|
|
return -1;
|
|
pos += icv_len;
|
|
|
|
*prot_len = pos - prot;
|
|
return 0;
|
|
}
|
|
|
|
|
|
int eap_eke_decrypt_prot(struct eap_eke_session *sess,
|
|
const u8 *prot, size_t prot_len,
|
|
u8 *data, size_t *data_len)
|
|
{
|
|
size_t block_size, icv_len;
|
|
u8 icv[EAP_EKE_MAX_HASH_LEN];
|
|
|
|
if (sess->encr == EAP_EKE_ENCR_AES128_CBC)
|
|
block_size = AES_BLOCK_SIZE;
|
|
else
|
|
return -1;
|
|
|
|
if (sess->mac == EAP_EKE_PRF_HMAC_SHA1)
|
|
icv_len = SHA1_MAC_LEN;
|
|
else if (sess->mac == EAP_EKE_PRF_HMAC_SHA2_256)
|
|
icv_len = SHA256_MAC_LEN;
|
|
else
|
|
return -1;
|
|
|
|
if (prot_len < 2 * block_size + icv_len)
|
|
return -1;
|
|
if ((prot_len - icv_len) % block_size)
|
|
return -1;
|
|
|
|
if (eap_eke_mac(sess->mac, sess->ki, prot + block_size,
|
|
prot_len - block_size - icv_len, icv) < 0)
|
|
return -1;
|
|
if (os_memcmp_const(icv, prot + prot_len - icv_len, icv_len) != 0) {
|
|
wpa_printf(MSG_INFO, "EAP-EKE: ICV mismatch in Prot() data");
|
|
return -1;
|
|
}
|
|
|
|
if (*data_len < prot_len - block_size - icv_len) {
|
|
wpa_printf(MSG_INFO, "EAP-EKE: Not enough room for decrypted Prot() data");
|
|
return -1;
|
|
}
|
|
|
|
*data_len = prot_len - block_size - icv_len;
|
|
os_memcpy(data, prot + block_size, *data_len);
|
|
if (aes_128_cbc_decrypt(sess->ke, prot, data, *data_len) < 0) {
|
|
wpa_printf(MSG_INFO, "EAP-EKE: Failed to decrypt Prot() data");
|
|
return -1;
|
|
}
|
|
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Decrypted Prot() data",
|
|
data, *data_len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
int eap_eke_auth(struct eap_eke_session *sess, const char *label,
|
|
const struct wpabuf *msgs, u8 *auth)
|
|
{
|
|
wpa_printf(MSG_DEBUG, "EAP-EKE: Auth(%s)", label);
|
|
wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: Ka for Auth",
|
|
sess->ka, sess->auth_len);
|
|
wpa_hexdump_buf(MSG_MSGDUMP, "EAP-EKE: Messages for Auth", msgs);
|
|
return eap_eke_prf(sess->prf, sess->ka, sess->auth_len,
|
|
(const u8 *) label, os_strlen(label),
|
|
wpabuf_head(msgs), wpabuf_len(msgs), auth);
|
|
}
|
|
|
|
|
|
int eap_eke_session_init(struct eap_eke_session *sess, u8 dhgroup, u8 encr,
|
|
u8 prf, u8 mac)
|
|
{
|
|
sess->dhgroup = dhgroup;
|
|
sess->encr = encr;
|
|
sess->prf = prf;
|
|
sess->mac = mac;
|
|
|
|
sess->prf_len = eap_eke_prf_len(prf);
|
|
if (sess->prf_len < 0)
|
|
return -1;
|
|
sess->nonce_len = eap_eke_nonce_len(prf);
|
|
if (sess->nonce_len < 0)
|
|
return -1;
|
|
sess->auth_len = eap_eke_auth_len(prf);
|
|
if (sess->auth_len < 0)
|
|
return -1;
|
|
sess->dhcomp_len = eap_eke_dhcomp_len(sess->dhgroup, sess->encr);
|
|
if (sess->dhcomp_len < 0)
|
|
return -1;
|
|
sess->pnonce_len = eap_eke_pnonce_len(sess->mac);
|
|
if (sess->pnonce_len < 0)
|
|
return -1;
|
|
sess->pnonce_ps_len = eap_eke_pnonce_ps_len(sess->mac);
|
|
if (sess->pnonce_ps_len < 0)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
void eap_eke_session_clean(struct eap_eke_session *sess)
|
|
{
|
|
os_memset(sess->shared_secret, 0, EAP_EKE_MAX_HASH_LEN);
|
|
os_memset(sess->ke, 0, EAP_EKE_MAX_KE_LEN);
|
|
os_memset(sess->ki, 0, EAP_EKE_MAX_KI_LEN);
|
|
os_memset(sess->ka, 0, EAP_EKE_MAX_KA_LEN);
|
|
}
|