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author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2009-03-28 21:29:51 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-03-28 21:29:51 +0100 |
commit | ed40d0c472b136682b2fcba05f89762859c7374f (patch) | |
tree | 076b83a26bcd63d6158463735dd34c10bbc591dc /net/mac80211/aes_cmac.c | |
parent | [ARM] 5434/1: ARM: OMAP: Fix mailbox compile for 24xx (diff) | |
parent | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 (diff) | |
download | linux-ed40d0c472b136682b2fcba05f89762859c7374f.tar.xz linux-ed40d0c472b136682b2fcba05f89762859c7374f.zip |
Merge branch 'origin' into devel
Conflicts:
sound/soc/pxa/pxa2xx-i2s.c
Diffstat (limited to 'net/mac80211/aes_cmac.c')
-rw-r--r-- | net/mac80211/aes_cmac.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/net/mac80211/aes_cmac.c b/net/mac80211/aes_cmac.c new file mode 100644 index 000000000000..3d097b3d7b62 --- /dev/null +++ b/net/mac80211/aes_cmac.c @@ -0,0 +1,135 @@ +/* + * AES-128-CMAC with TLen 16 for IEEE 802.11w BIP + * Copyright 2008, Jouni Malinen <j@w1.fi> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/crypto.h> +#include <linux/err.h> + +#include <net/mac80211.h> +#include "key.h" +#include "aes_cmac.h" + +#define AES_BLOCK_SIZE 16 +#define AES_CMAC_KEY_LEN 16 +#define CMAC_TLEN 8 /* CMAC TLen = 64 bits (8 octets) */ +#define AAD_LEN 20 + + +static void gf_mulx(u8 *pad) +{ + int i, carry; + + carry = pad[0] & 0x80; + for (i = 0; i < AES_BLOCK_SIZE - 1; i++) + pad[i] = (pad[i] << 1) | (pad[i + 1] >> 7); + pad[AES_BLOCK_SIZE - 1] <<= 1; + if (carry) + pad[AES_BLOCK_SIZE - 1] ^= 0x87; +} + + +static void aes_128_cmac_vector(struct crypto_cipher *tfm, u8 *scratch, + size_t num_elem, + const u8 *addr[], const size_t *len, u8 *mac) +{ + u8 *cbc, *pad; + const u8 *pos, *end; + size_t i, e, left, total_len; + + cbc = scratch; + pad = scratch + AES_BLOCK_SIZE; + + memset(cbc, 0, AES_BLOCK_SIZE); + + total_len = 0; + for (e = 0; e < num_elem; e++) + total_len += len[e]; + left = total_len; + + e = 0; + pos = addr[0]; + end = pos + len[0]; + + while (left >= AES_BLOCK_SIZE) { + for (i = 0; i < AES_BLOCK_SIZE; i++) { + cbc[i] ^= *pos++; + if (pos >= end) { + e++; + pos = addr[e]; + end = pos + len[e]; + } + } + if (left > AES_BLOCK_SIZE) + crypto_cipher_encrypt_one(tfm, cbc, cbc); + left -= AES_BLOCK_SIZE; + } + + memset(pad, 0, AES_BLOCK_SIZE); + crypto_cipher_encrypt_one(tfm, pad, pad); + gf_mulx(pad); + + if (left || total_len == 0) { + for (i = 0; i < left; i++) { + cbc[i] ^= *pos++; + if (pos >= end) { + e++; + pos = addr[e]; + end = pos + len[e]; + } + } + cbc[left] ^= 0x80; + gf_mulx(pad); + } + + for (i = 0; i < AES_BLOCK_SIZE; i++) + pad[i] ^= cbc[i]; + crypto_cipher_encrypt_one(tfm, pad, pad); + memcpy(mac, pad, CMAC_TLEN); +} + + +void ieee80211_aes_cmac(struct crypto_cipher *tfm, u8 *scratch, const u8 *aad, + const u8 *data, size_t data_len, u8 *mic) +{ + const u8 *addr[3]; + size_t len[3]; + u8 zero[CMAC_TLEN]; + + memset(zero, 0, CMAC_TLEN); + addr[0] = aad; + len[0] = AAD_LEN; + addr[1] = data; + len[1] = data_len - CMAC_TLEN; + addr[2] = zero; + len[2] = CMAC_TLEN; + + aes_128_cmac_vector(tfm, scratch, 3, addr, len, mic); +} + + +struct crypto_cipher * ieee80211_aes_cmac_key_setup(const u8 key[]) +{ + struct crypto_cipher *tfm; + + tfm = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(tfm)) + return NULL; + + crypto_cipher_setkey(tfm, key, AES_CMAC_KEY_LEN); + + return tfm; +} + + +void ieee80211_aes_cmac_key_free(struct crypto_cipher *tfm) +{ + if (tfm) + crypto_free_cipher(tfm); +} |