| /* |
| * EAP server/peer: EAP-PSK shared routines |
| * Copyright (c) 2004-2006, Jouni Malinen <j@w1.fi> |
| * |
| * This software may be distributed under the terms of the BSD license. |
| * See README for more details. |
| */ |
| |
| #include "includes.h" |
| |
| #include "common.h" |
| #include "crypto/aes_wrap.h" |
| #include "eap_defs.h" |
| #include "eap_psk_common.h" |
| |
| #define aes_block_size 16 |
| |
| |
| int eap_psk_key_setup(const u8 *psk, u8 *ak, u8 *kdk) |
| { |
| os_memset(ak, 0, aes_block_size); |
| if (aes_128_encrypt_block(psk, ak, ak)) |
| return -1; |
| os_memcpy(kdk, ak, aes_block_size); |
| ak[aes_block_size - 1] ^= 0x01; |
| kdk[aes_block_size - 1] ^= 0x02; |
| if (aes_128_encrypt_block(psk, ak, ak) || |
| aes_128_encrypt_block(psk, kdk, kdk)) |
| return -1; |
| return 0; |
| } |
| |
| |
| int eap_psk_derive_keys(const u8 *kdk, const u8 *rand_p, u8 *tek, u8 *msk, |
| u8 *emsk) |
| { |
| u8 hash[aes_block_size]; |
| u8 counter = 1; |
| int i; |
| |
| if (aes_128_encrypt_block(kdk, rand_p, hash)) |
| return -1; |
| |
| hash[aes_block_size - 1] ^= counter; |
| if (aes_128_encrypt_block(kdk, hash, tek)) |
| return -1; |
| hash[aes_block_size - 1] ^= counter; |
| counter++; |
| |
| for (i = 0; i < EAP_MSK_LEN / aes_block_size; i++) { |
| hash[aes_block_size - 1] ^= counter; |
| if (aes_128_encrypt_block(kdk, hash, &msk[i * aes_block_size])) |
| return -1; |
| hash[aes_block_size - 1] ^= counter; |
| counter++; |
| } |
| |
| for (i = 0; i < EAP_EMSK_LEN / aes_block_size; i++) { |
| hash[aes_block_size - 1] ^= counter; |
| if (aes_128_encrypt_block(kdk, hash, |
| &emsk[i * aes_block_size])) |
| return -1; |
| hash[aes_block_size - 1] ^= counter; |
| counter++; |
| } |
| |
| return 0; |
| } |
