Before reworking the AES CMAC mac80211 code, clone the routines that it shares with the FILS AEAD driver into its own source file, and remove the external declaration from aes_cmac.h. This will allow us to carry over one user at a time from the open coded CMAC code to the crypto API.
Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org> --- net/mac80211/aes_cmac.h | 4 -- net/mac80211/fils_aead.c | 68 ++++++++++++++++++++ 2 files changed, 68 insertions(+), 4 deletions(-) diff --git a/net/mac80211/aes_cmac.h b/net/mac80211/aes_cmac.h index c827e1d5de8b..3702041f44fd 100644 --- a/net/mac80211/aes_cmac.h +++ b/net/mac80211/aes_cmac.h @@ -11,10 +11,6 @@ #include <linux/crypto.h> -void gf_mulx(u8 *pad); -void aes_cmac_vector(struct crypto_cipher *tfm, size_t num_elem, - const u8 *addr[], const size_t *len, u8 *mac, - size_t mac_len); struct crypto_cipher *ieee80211_aes_cmac_key_setup(const u8 key[], size_t key_len); void ieee80211_aes_cmac(struct crypto_cipher *tfm, const u8 *aad, diff --git a/net/mac80211/fils_aead.c b/net/mac80211/fils_aead.c index ecfdd97758a3..ec493e68957c 100644 --- a/net/mac80211/fils_aead.c +++ b/net/mac80211/fils_aead.c @@ -15,6 +15,74 @@ #include "aes_cmac.h" #include "fils_aead.h" +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_cmac_vector(struct crypto_cipher *tfm, size_t num_elem, + const u8 *addr[], const size_t *len, u8 *mac, + size_t mac_len) +{ + u8 cbc[AES_BLOCK_SIZE], pad[AES_BLOCK_SIZE]; + const u8 *pos, *end; + size_t i, e, left, total_len; + + 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, mac_len); +} + static int aes_s2v(struct crypto_cipher *tfm, size_t num_elem, const u8 *addr[], size_t len[], u8 *v) { -- 2.7.4