denozord/strongswan-ext
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

aesni: Implement 256-bit key schedule

Browse Source
This commit is contained in:
Martin Willi
2015-04-15 11:35:27 +02:00
parent d7811415ff
commit b2d96bfe25
1 changed files with 77 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/libstrongswan/plugins/aesni/aesni_key.c
+77
View File
@@ -20,6 +20,7 @@
*/
#define AES128_ROUNDS 10
#define AES192_ROUNDS 12
#define AES256_ROUNDS 14
typedef struct private_aesni_key_t private_aesni_key_t;
@@ -169,6 +170,76 @@ static void expand192(__m128i *key, __m128i *schedule)
schedule[12] = t1;
}
/**
* Assist in creating a 256-bit round key
*/
static __m128i assist256_1(__m128i a, __m128i b)
{
__m128i x, y;
b = _mm_shuffle_epi32(b, 0xff);
y = _mm_slli_si128(a, 0x04);
x = _mm_xor_si128(a, y);
y = _mm_slli_si128(y, 0x04);
x = _mm_xor_si128 (x, y);
y = _mm_slli_si128(y, 0x04);
x = _mm_xor_si128(x, y);
x = _mm_xor_si128(x, b);
return x;
}
/**
* Assist in creating a 256-bit round key
*/
static __m128i assist256_2(__m128i a, __m128i b)
{
__m128i x, y, z;
y = _mm_aeskeygenassist_si128(a, 0x00);
z = _mm_shuffle_epi32(y, 0xaa);
y = _mm_slli_si128(b, 0x04);
x = _mm_xor_si128(b, y);
y = _mm_slli_si128(y, 0x04);
x = _mm_xor_si128(x, y);
y = _mm_slli_si128(y, 0x04);
x = _mm_xor_si128(x, y);
x = _mm_xor_si128(x, z);
return x;
}
/**
* Expand a 256-bit encryption key to round keys
*/
static void expand256(__m128i *key, __m128i *schedule)
{
__m128i t1, t2;
schedule[0] = t1 = _mm_loadu_si128(key);
schedule[1] = t2 = _mm_loadu_si128(key + 1);
schedule[2] = t1 = assist256_1(t1, _mm_aeskeygenassist_si128(t2, 0x01));
schedule[3] = t2 = assist256_2(t1, t2);
schedule[4] = t1 = assist256_1(t1, _mm_aeskeygenassist_si128(t2, 0x02));
schedule[5] = t2 = assist256_2(t1, t2);
schedule[6] = t1 = assist256_1(t1, _mm_aeskeygenassist_si128(t2, 0x04));
schedule[7] = t2 = assist256_2(t1, t2);
schedule[8] = t1 = assist256_1(t1, _mm_aeskeygenassist_si128(t2, 0x08));
schedule[9] = t2 = assist256_2(t1, t2);
schedule[10] = t1 = assist256_1(t1, _mm_aeskeygenassist_si128(t2, 0x10));
schedule[11] = t2 = assist256_2(t1, t2);
schedule[12] = t1 = assist256_1(t1, _mm_aeskeygenassist_si128(t2, 0x20));
schedule[13] = t2 = assist256_2(t1, t2);
schedule[14] = assist256_1(t1, _mm_aeskeygenassist_si128(t2, 0x40));
}
METHOD(aesni_key_t, destroy, void,
private_aesni_key_t *this)
{
@@ -192,6 +263,9 @@ aesni_key_t *aesni_key_create(bool encrypt, chunk_t key)
case 24:
rounds = AES192_ROUNDS;
break;
case 32:
rounds = AES256_ROUNDS;
break;
default:
return NULL;
}
@@ -211,6 +285,9 @@ aesni_key_t *aesni_key_create(bool encrypt, chunk_t key)
case 24:
expand192((__m128i*)key.ptr, this->public.schedule);
break;
case 32:
expand256((__m128i*)key.ptr, this->public.schedule);
break;
default:
break;
}