diff options
Diffstat (limited to 'gpxe/src/net/80211/wpa_tkip.c')
| -rw-r--r-- | gpxe/src/net/80211/wpa_tkip.c | 586 |
1 files changed, 0 insertions, 586 deletions
diff --git a/gpxe/src/net/80211/wpa_tkip.c b/gpxe/src/net/80211/wpa_tkip.c deleted file mode 100644 index 0cb697fa..00000000 --- a/gpxe/src/net/80211/wpa_tkip.c +++ /dev/null @@ -1,586 +0,0 @@ -/* - * Copyright (c) 2009 Joshua Oreman <oremanj@rwcr.net>. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of the - * License, or any later version. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - */ - -FILE_LICENCE ( GPL2_OR_LATER ); - -#include <gpxe/net80211.h> -#include <gpxe/crypto.h> -#include <gpxe/hmac.h> -#include <gpxe/sha1.h> -#include <gpxe/md5.h> -#include <gpxe/crc32.h> -#include <gpxe/arc4.h> -#include <gpxe/wpa.h> -#include <byteswap.h> -#include <errno.h> - -/** @file - * - * Backend for WPA using the TKIP encryption standard. - */ - -/** Context for one direction of TKIP, either encryption or decryption */ -struct tkip_dir_ctx -{ - /** High 32 bits of last sequence counter value used */ - u32 tsc_hi; - - /** Low 32 bits of last sequence counter value used */ - u16 tsc_lo; - - /** MAC address used to derive TTAK */ - u8 mac[ETH_ALEN]; - - /** If TRUE, TTAK is valid */ - u16 ttak_ok; - - /** TKIP-mixed transmit address and key, depends on tsc_hi and MAC */ - u16 ttak[5]; -}; - -/** Context for TKIP encryption and decryption */ -struct tkip_ctx -{ - /** Temporal key to use */ - struct tkip_tk tk; - - /** State for encryption */ - struct tkip_dir_ctx enc; - - /** State for decryption */ - struct tkip_dir_ctx dec; -}; - -/** Header structure at the beginning of TKIP frame data */ -struct tkip_head -{ - u8 tsc1; /**< High byte of low 16 bits of TSC */ - u8 seed1; /**< Second byte of WEP seed */ - u8 tsc0; /**< Low byte of TSC */ - u8 kid; /**< Key ID and ExtIV byte */ - u32 tsc_hi; /**< High 32 bits of TSC, as an ExtIV */ -} __attribute__ (( packed )); - - -/** TKIP header overhead (IV + KID + ExtIV) */ -#define TKIP_HEAD_LEN 8 - -/** TKIP trailer overhead (MIC + ICV) [assumes unfragmented] */ -#define TKIP_FOOT_LEN 12 - -/** TKIP MIC length */ -#define TKIP_MIC_LEN 8 - -/** TKIP ICV length */ -#define TKIP_ICV_LEN 4 - - -/** TKIP S-box */ -static const u16 Sbox[256] = { - 0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154, - 0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A, - 0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B, - 0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B, - 0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F, - 0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F, - 0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5, - 0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F, - 0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB, - 0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397, - 0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED, - 0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A, - 0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194, - 0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3, - 0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104, - 0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D, - 0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39, - 0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695, - 0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83, - 0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76, - 0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4, - 0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B, - 0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0, - 0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018, - 0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751, - 0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85, - 0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12, - 0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9, - 0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7, - 0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A, - 0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8, - 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A, -}; - -/** - * Perform S-box mapping on a 16-bit value - * - * @v v Value to perform S-box mapping on - * @ret Sv S-box mapped value - */ -static inline u16 S ( u16 v ) -{ - return Sbox[v & 0xFF] ^ swap16 ( Sbox[v >> 8] ); -} - -/** - * Rotate 16-bit value right - * - * @v v Value to rotate - * @v bits Number of bits to rotate by - * @ret rotv Rotated value - */ -static inline u16 ror16 ( u16 v, int bits ) -{ - return ( v >> bits ) | ( v << ( 16 - bits ) ); -} - -/** - * Rotate 32-bit value right - * - * @v v Value to rotate - * @v bits Number of bits to rotate by - * @ret rotv Rotated value - */ -static inline u32 ror32 ( u32 v, int bits ) -{ - return ( v >> bits ) | ( v << ( 32 - bits ) ); -} - -/** - * Rotate 32-bit value left - * - * @v v Value to rotate - * @v bits Number of bits to rotate by - * @ret rotv Rotated value - */ -static inline u32 rol32 ( u32 v, int bits ) -{ - return ( v << bits ) | ( v >> ( 32 - bits ) ); -} - - -/** - * Initialise TKIP state and install key - * - * @v crypto TKIP cryptosystem structure - * @v key Pointer to tkip_tk to install - * @v keylen Length of key (32 bytes) - * @v rsc Initial receive sequence counter - */ -static int tkip_init ( struct net80211_crypto *crypto, const void *key, - int keylen, const void *rsc ) -{ - struct tkip_ctx *ctx = crypto->priv; - const u8 *rscb = rsc; - - if ( keylen != sizeof ( ctx->tk ) ) - return -EINVAL; - - if ( rscb ) { - ctx->dec.tsc_lo = ( rscb[1] << 8 ) | rscb[0]; - ctx->dec.tsc_hi = ( ( rscb[5] << 24 ) | ( rscb[4] << 16 ) | - ( rscb[3] << 8 ) | rscb[2] ); - } - - memcpy ( &ctx->tk, key, sizeof ( ctx->tk ) ); - - return 0; -} - -/** - * Perform TKIP key mixing, phase 1 - * - * @v dctx TKIP directional context - * @v tk TKIP temporal key - * @v mac MAC address of transmitter - * - * This recomputes the TTAK in @a dctx if necessary, and sets - * @c dctx->ttak_ok. - */ -static void tkip_mix_1 ( struct tkip_dir_ctx *dctx, struct tkip_tk *tk, u8 *mac ) -{ - int i, j; - - if ( dctx->ttak_ok && ! memcmp ( mac, dctx->mac, ETH_ALEN ) ) - return; - - memcpy ( dctx->mac, mac, ETH_ALEN ); - - dctx->ttak[0] = dctx->tsc_hi & 0xFFFF; - dctx->ttak[1] = dctx->tsc_hi >> 16; - dctx->ttak[2] = ( mac[1] << 8 ) | mac[0]; - dctx->ttak[3] = ( mac[3] << 8 ) | mac[2]; - dctx->ttak[4] = ( mac[5] << 8 ) | mac[4]; - - for ( i = 0; i < 8; i++ ) { - j = 2 * ( i & 1 ); - - dctx->ttak[0] += S ( dctx->ttak[4] ^ ( ( tk->key[1 + j] << 8 ) | - tk->key[0 + j] ) ); - dctx->ttak[1] += S ( dctx->ttak[0] ^ ( ( tk->key[5 + j] << 8 ) | - tk->key[4 + j] ) ); - dctx->ttak[2] += S ( dctx->ttak[1] ^ ( ( tk->key[9 + j] << 8 ) | - tk->key[8 + j] ) ); - dctx->ttak[3] += S ( dctx->ttak[2] ^ ( ( tk->key[13+ j] << 8 ) | - tk->key[12+ j] ) ); - dctx->ttak[4] += S ( dctx->ttak[3] ^ ( ( tk->key[1 + j] << 8 ) | - tk->key[0 + j] ) ) + i; - } - - dctx->ttak_ok = 1; -} - -/** - * Perform TKIP key mixing, phase 2 - * - * @v dctx TKIP directional context - * @v tk TKIP temporal key - * @ret key ARC4 key, 16 bytes long - */ -static void tkip_mix_2 ( struct tkip_dir_ctx *dctx, struct tkip_tk *tk, - void *key ) -{ - u8 *kb = key; - u16 ppk[6]; - int i; - - memcpy ( ppk, dctx->ttak, sizeof ( dctx->ttak ) ); - ppk[5] = dctx->ttak[4] + dctx->tsc_lo; - - ppk[0] += S ( ppk[5] ^ ( ( tk->key[1] << 8 ) | tk->key[0] ) ); - ppk[1] += S ( ppk[0] ^ ( ( tk->key[3] << 8 ) | tk->key[2] ) ); - ppk[2] += S ( ppk[1] ^ ( ( tk->key[5] << 8 ) | tk->key[4] ) ); - ppk[3] += S ( ppk[2] ^ ( ( tk->key[7] << 8 ) | tk->key[6] ) ); - ppk[4] += S ( ppk[3] ^ ( ( tk->key[9] << 8 ) | tk->key[8] ) ); - ppk[5] += S ( ppk[4] ^ ( ( tk->key[11] << 8 ) | tk->key[10] ) ); - - ppk[0] += ror16 ( ppk[5] ^ ( ( tk->key[13] << 8 ) | tk->key[12] ), 1 ); - ppk[1] += ror16 ( ppk[0] ^ ( ( tk->key[15] << 8 ) | tk->key[14] ), 1 ); - ppk[2] += ror16 ( ppk[1], 1 ); - ppk[3] += ror16 ( ppk[2], 1 ); - ppk[4] += ror16 ( ppk[3], 1 ); - ppk[5] += ror16 ( ppk[4], 1 ); - - kb[0] = dctx->tsc_lo >> 8; - kb[1] = ( ( dctx->tsc_lo >> 8 ) | 0x20 ) & 0x7F; - kb[2] = dctx->tsc_lo & 0xFF; - kb[3] = ( ( ppk[5] ^ ( ( tk->key[1] << 8 ) | tk->key[0] ) ) >> 1 ) - & 0xFF; - - for ( i = 0; i < 6; i++ ) { - kb[4 + 2*i] = ppk[i] & 0xFF; - kb[5 + 2*i] = ppk[i] >> 8; - } -} - -/** - * Update Michael message integrity code based on next 32-bit word of data - * - * @v V Michael code state (two 32-bit words) - * @v word Next 32-bit word of data - */ -static void tkip_feed_michael ( u32 *V, u32 word ) -{ - V[0] ^= word; - V[1] ^= rol32 ( V[0], 17 ); - V[0] += V[1]; - V[1] ^= ( ( V[0] & 0xFF00FF00 ) >> 8 ) | ( ( V[0] & 0x00FF00FF ) << 8 ); - V[0] += V[1]; - V[1] ^= rol32 ( V[0], 3 ); - V[0] += V[1]; - V[1] ^= ror32 ( V[0], 2 ); - V[0] += V[1]; -} - -/** - * Calculate Michael message integrity code - * - * @v key MIC key to use (8 bytes) - * @v da Destination link-layer address - * @v sa Source link-layer address - * @v data Start of data to calculate over - * @v len Length of header + data - * @ret mic Calculated Michael MIC (8 bytes) - */ -static void tkip_michael ( const void *key, const void *da, const void *sa, - const void *data, size_t len, void *mic ) -{ - u32 V[2]; /* V[0] = "l", V[1] = "r" in 802.11 */ - union { - u8 byte[12]; - u32 word[3]; - } cap; - const u8 *ptr = data; - const u8 *end = ptr + len; - int i; - - memcpy ( V, key, sizeof ( V ) ); - V[0] = le32_to_cpu ( V[0] ); - V[1] = le32_to_cpu ( V[1] ); - - /* Feed in header (we assume non-QoS, so Priority = 0) */ - memcpy ( &cap.byte[0], da, ETH_ALEN ); - memcpy ( &cap.byte[6], sa, ETH_ALEN ); - tkip_feed_michael ( V, le32_to_cpu ( cap.word[0] ) ); - tkip_feed_michael ( V, le32_to_cpu ( cap.word[1] ) ); - tkip_feed_michael ( V, le32_to_cpu ( cap.word[2] ) ); - tkip_feed_michael ( V, 0 ); - - /* Feed in data */ - while ( ptr + 4 <= end ) { - tkip_feed_michael ( V, le32_to_cpu ( *( u32 * ) ptr ) ); - ptr += 4; - } - - /* Add unaligned part and padding */ - for ( i = 0; ptr < end; i++ ) - cap.byte[i] = *ptr++; - cap.byte[i++] = 0x5a; - for ( ; i < 8; i++ ) - cap.byte[i] = 0; - - /* Feed in padding */ - tkip_feed_michael ( V, le32_to_cpu ( cap.word[0] ) ); - tkip_feed_michael ( V, le32_to_cpu ( cap.word[1] ) ); - - /* Output MIC */ - V[0] = cpu_to_le32 ( V[0] ); - V[1] = cpu_to_le32 ( V[1] ); - memcpy ( mic, V, sizeof ( V ) ); -} - -/** - * Encrypt a packet using TKIP - * - * @v crypto TKIP cryptosystem - * @v iob I/O buffer containing cleartext packet - * @ret eiob I/O buffer containing encrypted packet - */ -static struct io_buffer * tkip_encrypt ( struct net80211_crypto *crypto, - struct io_buffer *iob ) -{ - struct tkip_ctx *ctx = crypto->priv; - struct ieee80211_frame *hdr = iob->data; - struct io_buffer *eiob; - struct arc4_ctx arc4; - u8 key[16]; - struct tkip_head head; - u8 mic[8]; - u32 icv; - const int hdrlen = IEEE80211_TYP_FRAME_HEADER_LEN; - int datalen = iob_len ( iob ) - hdrlen; - - ctx->enc.tsc_lo++; - if ( ctx->enc.tsc_lo == 0 ) { - ctx->enc.tsc_hi++; - ctx->enc.ttak_ok = 0; - } - - tkip_mix_1 ( &ctx->enc, &ctx->tk, hdr->addr2 ); - tkip_mix_2 ( &ctx->enc, &ctx->tk, key ); - - eiob = alloc_iob ( iob_len ( iob ) + TKIP_HEAD_LEN + TKIP_FOOT_LEN ); - if ( ! eiob ) - return NULL; - - /* Copy frame header */ - memcpy ( iob_put ( eiob, hdrlen ), iob->data, hdrlen ); - hdr = eiob->data; - hdr->fc |= IEEE80211_FC_PROTECTED; - - /* Fill in IV and key ID byte, and extended IV */ - memcpy ( &head, key, 3 ); - head.kid = 0x20; /* have Extended IV, key ID 0 */ - head.tsc_hi = cpu_to_le32 ( ctx->enc.tsc_hi ); - memcpy ( iob_put ( eiob, sizeof ( head ) ), &head, sizeof ( head ) ); - - /* Copy and encrypt the data */ - cipher_setkey ( &arc4_algorithm, &arc4, key, 16 ); - cipher_encrypt ( &arc4_algorithm, &arc4, iob->data + hdrlen, - iob_put ( eiob, datalen ), datalen ); - - /* Add MIC */ - hdr = iob->data; - tkip_michael ( &ctx->tk.mic.tx, hdr->addr3, hdr->addr2, - iob->data + hdrlen, datalen, mic ); - cipher_encrypt ( &arc4_algorithm, &arc4, mic, - iob_put ( eiob, sizeof ( mic ) ), sizeof ( mic ) ); - - /* Add ICV */ - icv = crc32_le ( ~0, iob->data + hdrlen, datalen ); - icv = crc32_le ( icv, mic, sizeof ( mic ) ); - icv = cpu_to_le32 ( ~icv ); - cipher_encrypt ( &arc4_algorithm, &arc4, &icv, - iob_put ( eiob, TKIP_ICV_LEN ), TKIP_ICV_LEN ); - - DBGC2 ( ctx, "WPA-TKIP %p: encrypted packet %p -> %p\n", ctx, - iob, eiob ); - - return eiob; -} - -/** - * Decrypt a packet using TKIP - * - * @v crypto TKIP cryptosystem - * @v eiob I/O buffer containing encrypted packet - * @ret iob I/O buffer containing cleartext packet - */ -static struct io_buffer * tkip_decrypt ( struct net80211_crypto *crypto, - struct io_buffer *eiob ) -{ - struct tkip_ctx *ctx = crypto->priv; - struct ieee80211_frame *hdr; - struct io_buffer *iob; - const int hdrlen = IEEE80211_TYP_FRAME_HEADER_LEN; - int datalen = iob_len ( eiob ) - hdrlen - TKIP_HEAD_LEN - TKIP_FOOT_LEN; - struct tkip_head *head; - struct arc4_ctx arc4; - u16 rx_tsc_lo; - u8 key[16]; - u8 mic[8]; - u32 icv, crc; - - iob = alloc_iob ( hdrlen + datalen + TKIP_FOOT_LEN ); - if ( ! iob ) - return NULL; - - /* Copy frame header */ - memcpy ( iob_put ( iob, hdrlen ), eiob->data, hdrlen ); - hdr = iob->data; - hdr->fc &= ~IEEE80211_FC_PROTECTED; - - /* Check and update TSC */ - head = eiob->data + hdrlen; - rx_tsc_lo = ( head->tsc1 << 8 ) | head->tsc0; - - if ( head->tsc_hi < ctx->dec.tsc_hi || - ( head->tsc_hi == ctx->dec.tsc_hi && - rx_tsc_lo <= ctx->dec.tsc_lo ) ) { - DBGC ( ctx, "WPA-TKIP %p: packet received out of order " - "(%08x:%04x <= %08x:%04x)\n", ctx, head->tsc_hi, - rx_tsc_lo, ctx->dec.tsc_hi, ctx->dec.tsc_lo ); - free_iob ( iob ); - return NULL; - } - ctx->dec.tsc_lo = rx_tsc_lo; - if ( ctx->dec.tsc_hi != head->tsc_hi ) { - ctx->dec.ttak_ok = 0; - ctx->dec.tsc_hi = head->tsc_hi; - } - - /* Calculate key */ - tkip_mix_1 ( &ctx->dec, &ctx->tk, hdr->addr2 ); - tkip_mix_2 ( &ctx->dec, &ctx->tk, key ); - - /* Copy-decrypt data, MIC, ICV */ - cipher_setkey ( &arc4_algorithm, &arc4, key, 16 ); - cipher_decrypt ( &arc4_algorithm, &arc4, - eiob->data + hdrlen + TKIP_HEAD_LEN, - iob_put ( iob, datalen ), datalen + TKIP_FOOT_LEN ); - - /* Check ICV */ - icv = le32_to_cpu ( *( u32 * ) ( iob->tail + TKIP_MIC_LEN ) ); - crc = ~crc32_le ( ~0, iob->data + hdrlen, datalen + TKIP_MIC_LEN ); - if ( crc != icv ) { - DBGC ( ctx, "WPA-TKIP %p CRC mismatch: expect %08x, get %08x\n", - ctx, icv, crc ); - free_iob ( iob ); - return NULL; - } - - /* Check MIC */ - tkip_michael ( &ctx->tk.mic.rx, hdr->addr1, hdr->addr3, - iob->data + hdrlen, datalen, mic ); - if ( memcmp ( mic, iob->tail, TKIP_MIC_LEN ) != 0 ) { - DBGC ( ctx, "WPA-TKIP %p ALERT! MIC failure\n", ctx ); - /* XXX we should do the countermeasures here */ - free_iob ( iob ); - return NULL; - } - - DBGC2 ( ctx, "WPA-TKIP %p: decrypted packet %p -> %p\n", ctx, - eiob, iob ); - - return iob; -} - -/** TKIP cryptosystem */ -struct net80211_crypto tkip_crypto __net80211_crypto = { - .algorithm = NET80211_CRYPT_TKIP, - .init = tkip_init, - .encrypt = tkip_encrypt, - .decrypt = tkip_decrypt, - .priv_len = sizeof ( struct tkip_ctx ), -}; - - - - -/** - * Calculate HMAC-MD5 MIC for EAPOL-Key frame - * - * @v kck Key Confirmation Key, 16 bytes - * @v msg Message to calculate MIC over - * @v len Number of bytes to calculate MIC over - * @ret mic Calculated MIC, 16 bytes long - */ -static void tkip_kie_mic ( const void *kck, const void *msg, size_t len, - void *mic ) -{ - struct md5_ctx md5; - u8 kckb[16]; - size_t kck_len = 16; - - memcpy ( kckb, kck, kck_len ); - - hmac_init ( &md5_algorithm, &md5, kckb, &kck_len ); - hmac_update ( &md5_algorithm, &md5, msg, len ); - hmac_final ( &md5_algorithm, &md5, kckb, &kck_len, mic ); -} - -/** - * Decrypt key data in EAPOL-Key frame - * - * @v kek Key Encryption Key, 16 bytes - * @v iv Initialisation vector, 16 bytes - * @v msg Message to decrypt - * @v len Length of message - * @ret msg Decrypted message in place of original - * @ret len Unchanged - * @ret rc Always 0 for success - */ -static int tkip_kie_decrypt ( const void *kek, const void *iv, - void *msg, u16 *len ) -{ - u8 key[32]; - memcpy ( key, iv, 16 ); - memcpy ( key + 16, kek, 16 ); - - arc4_skip ( key, 32, 256, msg, msg, *len ); - - return 0; -} - - -/** TKIP-style key integrity and encryption handler */ -struct wpa_kie tkip_kie __wpa_kie = { - .version = EAPOL_KEY_VERSION_WPA, - .mic = tkip_kie_mic, - .decrypt = tkip_kie_decrypt, -}; |