[PATCH 2/3] staging: rtl8723bs: use in-kernel aes encryption in OMAC1 routines

From: Fabio Aiuto
Date: Tue May 04 2021 - 09:13:08 EST


replace private aes encryption subroutines with
public in-kernel ones in OMAC1 computation routines.

Signed-off-by: Fabio Aiuto <fabioaiuto83@xxxxxxxxx>
---
drivers/staging/rtl8723bs/core/rtw_security.c | 113 ++----------------
.../staging/rtl8723bs/include/rtw_security.h | 1 +
2 files changed, 9 insertions(+), 105 deletions(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_security.c b/drivers/staging/rtl8723bs/core/rtw_security.c
index 0cb603aa4ee6..4f82dc9a3642 100644
--- a/drivers/staging/rtl8723bs/core/rtw_security.c
+++ b/drivers/staging/rtl8723bs/core/rtw_security.c
@@ -1931,99 +1931,6 @@ const u8 rcons[] = {
/* for 128-bit blocks, Rijndael never uses more than 10 rcon values */
};

-/*
- * Expand the cipher key into the encryption key schedule.
- *
- * @return the number of rounds for the given cipher key size.
- */
-static void rijndaelKeySetupEnc(u32 rk[/*44*/], const u8 cipherKey[])
-{
- int i;
- u32 temp;
-
- rk[0] = GETU32(cipherKey);
- rk[1] = GETU32(cipherKey + 4);
- rk[2] = GETU32(cipherKey + 8);
- rk[3] = GETU32(cipherKey + 12);
- for (i = 0; i < 10; i++) {
- temp = rk[3];
- rk[4] = rk[0] ^
- TE421(temp) ^ TE432(temp) ^ TE443(temp) ^ TE414(temp) ^
- RCON(i);
- rk[5] = rk[1] ^ rk[4];
- rk[6] = rk[2] ^ rk[5];
- rk[7] = rk[3] ^ rk[6];
- rk += 4;
- }
-}
-
-static void rijndaelEncrypt(u32 rk[/*44*/], u8 pt[16], u8 ct[16])
-{
- u32 s0, s1, s2, s3, t0, t1, t2, t3;
- int Nr = 10;
- int r;
-
- /*
- * map byte array block to cipher state
- * and add initial round key:
- */
- s0 = GETU32(pt) ^ rk[0];
- s1 = GETU32(pt + 4) ^ rk[1];
- s2 = GETU32(pt + 8) ^ rk[2];
- s3 = GETU32(pt + 12) ^ rk[3];
-
-#define ROUND(i, d, s) \
- do { \
- d##0 = TE0(s##0) ^ TE1(s##1) ^ TE2(s##2) ^ TE3(s##3) ^ rk[4 * i]; \
- d##1 = TE0(s##1) ^ TE1(s##2) ^ TE2(s##3) ^ TE3(s##0) ^ rk[4 * i + 1]; \
- d##2 = TE0(s##2) ^ TE1(s##3) ^ TE2(s##0) ^ TE3(s##1) ^ rk[4 * i + 2]; \
- d##3 = TE0(s##3) ^ TE1(s##0) ^ TE2(s##1) ^ TE3(s##2) ^ rk[4 * i + 3]; \
- } while (0)
-
- /* Nr - 1 full rounds: */
- r = Nr >> 1;
- for (;;) {
- ROUND(1, t, s);
- rk += 8;
- if (--r == 0)
- break;
- ROUND(0, s, t);
- }
-
-#undef ROUND
-
- /*
- * apply last round and
- * map cipher state to byte array block:
- */
- s0 = TE41(t0) ^ TE42(t1) ^ TE43(t2) ^ TE44(t3) ^ rk[0];
- PUTU32(ct, s0);
- s1 = TE41(t1) ^ TE42(t2) ^ TE43(t3) ^ TE44(t0) ^ rk[1];
- PUTU32(ct + 4, s1);
- s2 = TE41(t2) ^ TE42(t3) ^ TE43(t0) ^ TE44(t1) ^ rk[2];
- PUTU32(ct + 8, s2);
- s3 = TE41(t3) ^ TE42(t0) ^ TE43(t1) ^ TE44(t2) ^ rk[3];
- PUTU32(ct + 12, s3);
-}
-
-static void *aes_encrypt_init(u8 *key, size_t len)
-{
- u32 *rk;
-
- if (len != 16)
- return NULL;
- rk = rtw_malloc(AES_PRIV_SIZE);
- if (rk == NULL)
- return NULL;
- rijndaelKeySetupEnc(rk, key);
- return rk;
-}
-
-static void aes_128_encrypt(void *ctx, u8 *plain, u8 *crypt)
-{
- rijndaelEncrypt(ctx, plain, crypt);
-}
-
static void gf_mulx(u8 *pad)
{
int i, carry;
@@ -2037,11 +1944,6 @@ static void gf_mulx(u8 *pad)
pad[AES_BLOCK_SIZE - 1] ^= 0x87;
}

-static void aes_encrypt_deinit(void *ctx)
-{
- kfree_sensitive(ctx);
-}
-
/**
* omac1_aes_128_vector - One-Key CBC MAC (OMAC1) hash with AES-128
* @key: 128-bit key for the hash operation
@@ -2058,13 +1960,14 @@ static void aes_encrypt_deinit(void *ctx)
static int omac1_aes_128_vector(u8 *key, size_t num_elem,
u8 *addr[], size_t *len, u8 *mac)
{
- void *ctx;
+ struct crypto_aes_ctx ctx;
u8 cbc[AES_BLOCK_SIZE], pad[AES_BLOCK_SIZE];
u8 *pos, *end;
size_t i, e, left, total_len;
+ int ret;

- ctx = aes_encrypt_init(key, 16);
- if (ctx == NULL)
+ ret = aes_expandkey(&ctx, key, 16);
+ if (ret)
return -1;
memset(cbc, 0, AES_BLOCK_SIZE);

@@ -2087,12 +1990,12 @@ static int omac1_aes_128_vector(u8 *key, size_t num_elem,
}
}
if (left > AES_BLOCK_SIZE)
- aes_128_encrypt(ctx, cbc, cbc);
+ aes_encrypt(&ctx, cbc, cbc);
left -= AES_BLOCK_SIZE;
}

memset(pad, 0, AES_BLOCK_SIZE);
- aes_128_encrypt(ctx, pad, pad);
+ aes_encrypt(&ctx, pad, pad);
gf_mulx(pad);

if (left || total_len == 0) {
@@ -2110,8 +2013,8 @@ static int omac1_aes_128_vector(u8 *key, size_t num_elem,

for (i = 0; i < AES_BLOCK_SIZE; i++)
pad[i] ^= cbc[i];
- aes_128_encrypt(ctx, pad, mac);
- aes_encrypt_deinit(ctx);
+ aes_encrypt(&ctx, pad, mac);
+ memzero_explicit(&ctx, sizeof(ctx));
return 0;
}

diff --git a/drivers/staging/rtl8723bs/include/rtw_security.h b/drivers/staging/rtl8723bs/include/rtw_security.h
index 5c787e999aab..032e520317e7 100644
--- a/drivers/staging/rtl8723bs/include/rtw_security.h
+++ b/drivers/staging/rtl8723bs/include/rtw_security.h
@@ -7,6 +7,7 @@
#ifndef __RTW_SECURITY_H_
#define __RTW_SECURITY_H_

+#include <crypto/aes.h>

#define _NO_PRIVACY_ 0x0
#define _WEP40_ 0x1
--
2.20.1