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.biesheuvel@xxxxxxxxxx>
---
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
