Files
strongswan-ext/src/libstrongswan/plugins/aesni/aesni_ctr.c
T
Martin Willi 93f0080265 aesni: Align all class instances to 16 byte boundaries
While the required members are aligned in the struct as required, on 32-bit
platforms the allocator aligns the structures itself to 8 bytes only. This
results in non-aligned struct members, and invalid memory accesses.
2015-04-15 13:44:40 +02:00

683 lines
17 KiB
C

/*
* Copyright (C) 2015 Martin Willi
* Copyright (C) 2015 revosec AG
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*/
#include "aesni_ctr.h"
#include "aesni_key.h"
#include <tmmintrin.h>
/**
* Pipeline parallelism we use for CTR en/decryption
*/
#define CTR_CRYPT_PARALLELISM 4
typedef struct private_aesni_ctr_t private_aesni_ctr_t;
/**
* CTR en/decryption method type
*/
typedef void (*aesni_ctr_fn_t)(private_aesni_ctr_t*, size_t, u_char*, u_char*);
/**
* Private data of an aesni_ctr_t object.
*/
struct private_aesni_ctr_t {
/**
* Public aesni_ctr_t interface.
*/
aesni_ctr_t public;
/**
* Key size
*/
u_int key_size;
/**
* Key schedule
*/
aesni_key_t *key;
/**
* Encryption method
*/
aesni_ctr_fn_t crypt;
/**
* Counter state
*/
struct {
char nonce[4];
char iv[8];
u_int32_t counter;
} __attribute__((packed, aligned(sizeof(__m128i)))) state;
};
/**
* Do big-endian increment on x
*/
static inline __m128i increment_be(__m128i x)
{
__m128i swap;
swap = _mm_setr_epi8(15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0);
x = _mm_shuffle_epi8(x, swap);
x = _mm_add_epi64(x, _mm_set_epi32(0, 0, 0, 1));
x = _mm_shuffle_epi8(x, swap);
return x;
}
/**
* AES-128 CTR encryption
*/
static void encrypt_ctr128(private_aesni_ctr_t *this,
size_t len, u_char *in, u_char *out)
{
__m128i k0, k1, k2, k3, k4, k5, k6, k7, k8, k9, k10;
__m128i t1, t2, t3, t4;
__m128i d1, d2, d3, d4;
__m128i state, b, *bi, *bo;
u_int i, blocks, pblocks, rem;
state = _mm_load_si128((__m128i*)&this->state);
blocks = len / AES_BLOCK_SIZE;
pblocks = blocks - (blocks % CTR_CRYPT_PARALLELISM);
rem = len % AES_BLOCK_SIZE;
bi = (__m128i*)in;
bo = (__m128i*)out;
k0 = this->key->schedule[0];
k1 = this->key->schedule[1];
k2 = this->key->schedule[2];
k3 = this->key->schedule[3];
k4 = this->key->schedule[4];
k5 = this->key->schedule[5];
k6 = this->key->schedule[6];
k7 = this->key->schedule[7];
k8 = this->key->schedule[8];
k9 = this->key->schedule[9];
k10 = this->key->schedule[10];
for (i = 0; i < pblocks; i += CTR_CRYPT_PARALLELISM)
{
d1 = _mm_loadu_si128(bi + i + 0);
d2 = _mm_loadu_si128(bi + i + 1);
d3 = _mm_loadu_si128(bi + i + 2);
d4 = _mm_loadu_si128(bi + i + 3);
t1 = _mm_xor_si128(state, k0);
state = increment_be(state);
t2 = _mm_xor_si128(state, k0);
state = increment_be(state);
t3 = _mm_xor_si128(state, k0);
state = increment_be(state);
t4 = _mm_xor_si128(state, k0);
state = increment_be(state);
t1 = _mm_aesenc_si128(t1, k1);
t2 = _mm_aesenc_si128(t2, k1);
t3 = _mm_aesenc_si128(t3, k1);
t4 = _mm_aesenc_si128(t4, k1);
t1 = _mm_aesenc_si128(t1, k2);
t2 = _mm_aesenc_si128(t2, k2);
t3 = _mm_aesenc_si128(t3, k2);
t4 = _mm_aesenc_si128(t4, k2);
t1 = _mm_aesenc_si128(t1, k3);
t2 = _mm_aesenc_si128(t2, k3);
t3 = _mm_aesenc_si128(t3, k3);
t4 = _mm_aesenc_si128(t4, k3);
t1 = _mm_aesenc_si128(t1, k4);
t2 = _mm_aesenc_si128(t2, k4);
t3 = _mm_aesenc_si128(t3, k4);
t4 = _mm_aesenc_si128(t4, k4);
t1 = _mm_aesenc_si128(t1, k5);
t2 = _mm_aesenc_si128(t2, k5);
t3 = _mm_aesenc_si128(t3, k5);
t4 = _mm_aesenc_si128(t4, k5);
t1 = _mm_aesenc_si128(t1, k6);
t2 = _mm_aesenc_si128(t2, k6);
t3 = _mm_aesenc_si128(t3, k6);
t4 = _mm_aesenc_si128(t4, k6);
t1 = _mm_aesenc_si128(t1, k7);
t2 = _mm_aesenc_si128(t2, k7);
t3 = _mm_aesenc_si128(t3, k7);
t4 = _mm_aesenc_si128(t4, k7);
t1 = _mm_aesenc_si128(t1, k8);
t2 = _mm_aesenc_si128(t2, k8);
t3 = _mm_aesenc_si128(t3, k8);
t4 = _mm_aesenc_si128(t4, k8);
t1 = _mm_aesenc_si128(t1, k9);
t2 = _mm_aesenc_si128(t2, k9);
t3 = _mm_aesenc_si128(t3, k9);
t4 = _mm_aesenc_si128(t4, k9);
t1 = _mm_aesenclast_si128(t1, k10);
t2 = _mm_aesenclast_si128(t2, k10);
t3 = _mm_aesenclast_si128(t3, k10);
t4 = _mm_aesenclast_si128(t4, k10);
t1 = _mm_xor_si128(t1, d1);
t2 = _mm_xor_si128(t2, d2);
t3 = _mm_xor_si128(t3, d3);
t4 = _mm_xor_si128(t4, d4);
_mm_storeu_si128(bo + i + 0, t1);
_mm_storeu_si128(bo + i + 1, t2);
_mm_storeu_si128(bo + i + 2, t3);
_mm_storeu_si128(bo + i + 3, t4);
}
for (i = pblocks; i < blocks; i++)
{
d1 = _mm_loadu_si128(bi + i);
t1 = _mm_xor_si128(state, k0);
state = increment_be(state);
t1 = _mm_aesenc_si128(t1, k1);
t1 = _mm_aesenc_si128(t1, k2);
t1 = _mm_aesenc_si128(t1, k3);
t1 = _mm_aesenc_si128(t1, k4);
t1 = _mm_aesenc_si128(t1, k5);
t1 = _mm_aesenc_si128(t1, k6);
t1 = _mm_aesenc_si128(t1, k7);
t1 = _mm_aesenc_si128(t1, k8);
t1 = _mm_aesenc_si128(t1, k9);
t1 = _mm_aesenclast_si128(t1, k10);
t1 = _mm_xor_si128(t1, d1);
_mm_storeu_si128(bo + i, t1);
}
if (rem)
{
memset(&b, 0, sizeof(b));
memcpy(&b, bi + blocks, rem);
d1 = _mm_loadu_si128(&b);
t1 = _mm_xor_si128(state, k0);
t1 = _mm_aesenc_si128(t1, k1);
t1 = _mm_aesenc_si128(t1, k2);
t1 = _mm_aesenc_si128(t1, k3);
t1 = _mm_aesenc_si128(t1, k4);
t1 = _mm_aesenc_si128(t1, k5);
t1 = _mm_aesenc_si128(t1, k6);
t1 = _mm_aesenc_si128(t1, k7);
t1 = _mm_aesenc_si128(t1, k8);
t1 = _mm_aesenc_si128(t1, k9);
t1 = _mm_aesenclast_si128(t1, k10);
t1 = _mm_xor_si128(t1, d1);
_mm_storeu_si128(&b, t1);
memcpy(bo + blocks, &b, rem);
}
}
/**
* AES-192 CTR encryption
*/
static void encrypt_ctr192(private_aesni_ctr_t *this,
size_t len, u_char *in, u_char *out)
{
__m128i k0, k1, k2, k3, k4, k5, k6, k7, k8, k9, k10, k11, k12;
__m128i t1, t2, t3, t4;
__m128i d1, d2, d3, d4;
__m128i state, b, *bi, *bo;
u_int i, blocks, pblocks, rem;
state = _mm_load_si128((__m128i*)&this->state);
blocks = len / AES_BLOCK_SIZE;
pblocks = blocks - (blocks % CTR_CRYPT_PARALLELISM);
rem = len % AES_BLOCK_SIZE;
bi = (__m128i*)in;
bo = (__m128i*)out;
k0 = this->key->schedule[0];
k1 = this->key->schedule[1];
k2 = this->key->schedule[2];
k3 = this->key->schedule[3];
k4 = this->key->schedule[4];
k5 = this->key->schedule[5];
k6 = this->key->schedule[6];
k7 = this->key->schedule[7];
k8 = this->key->schedule[8];
k9 = this->key->schedule[9];
k10 = this->key->schedule[10];
k11 = this->key->schedule[11];
k12 = this->key->schedule[12];
for (i = 0; i < pblocks; i += CTR_CRYPT_PARALLELISM)
{
d1 = _mm_loadu_si128(bi + i + 0);
d2 = _mm_loadu_si128(bi + i + 1);
d3 = _mm_loadu_si128(bi + i + 2);
d4 = _mm_loadu_si128(bi + i + 3);
t1 = _mm_xor_si128(state, k0);
state = increment_be(state);
t2 = _mm_xor_si128(state, k0);
state = increment_be(state);
t3 = _mm_xor_si128(state, k0);
state = increment_be(state);
t4 = _mm_xor_si128(state, k0);
state = increment_be(state);
t1 = _mm_aesenc_si128(t1, k1);
t2 = _mm_aesenc_si128(t2, k1);
t3 = _mm_aesenc_si128(t3, k1);
t4 = _mm_aesenc_si128(t4, k1);
t1 = _mm_aesenc_si128(t1, k2);
t2 = _mm_aesenc_si128(t2, k2);
t3 = _mm_aesenc_si128(t3, k2);
t4 = _mm_aesenc_si128(t4, k2);
t1 = _mm_aesenc_si128(t1, k3);
t2 = _mm_aesenc_si128(t2, k3);
t3 = _mm_aesenc_si128(t3, k3);
t4 = _mm_aesenc_si128(t4, k3);
t1 = _mm_aesenc_si128(t1, k4);
t2 = _mm_aesenc_si128(t2, k4);
t3 = _mm_aesenc_si128(t3, k4);
t4 = _mm_aesenc_si128(t4, k4);
t1 = _mm_aesenc_si128(t1, k5);
t2 = _mm_aesenc_si128(t2, k5);
t3 = _mm_aesenc_si128(t3, k5);
t4 = _mm_aesenc_si128(t4, k5);
t1 = _mm_aesenc_si128(t1, k6);
t2 = _mm_aesenc_si128(t2, k6);
t3 = _mm_aesenc_si128(t3, k6);
t4 = _mm_aesenc_si128(t4, k6);
t1 = _mm_aesenc_si128(t1, k7);
t2 = _mm_aesenc_si128(t2, k7);
t3 = _mm_aesenc_si128(t3, k7);
t4 = _mm_aesenc_si128(t4, k7);
t1 = _mm_aesenc_si128(t1, k8);
t2 = _mm_aesenc_si128(t2, k8);
t3 = _mm_aesenc_si128(t3, k8);
t4 = _mm_aesenc_si128(t4, k8);
t1 = _mm_aesenc_si128(t1, k9);
t2 = _mm_aesenc_si128(t2, k9);
t3 = _mm_aesenc_si128(t3, k9);
t4 = _mm_aesenc_si128(t4, k9);
t1 = _mm_aesenc_si128(t1, k10);
t2 = _mm_aesenc_si128(t2, k10);
t3 = _mm_aesenc_si128(t3, k10);
t4 = _mm_aesenc_si128(t4, k10);
t1 = _mm_aesenc_si128(t1, k11);
t2 = _mm_aesenc_si128(t2, k11);
t3 = _mm_aesenc_si128(t3, k11);
t4 = _mm_aesenc_si128(t4, k11);
t1 = _mm_aesenclast_si128(t1, k12);
t2 = _mm_aesenclast_si128(t2, k12);
t3 = _mm_aesenclast_si128(t3, k12);
t4 = _mm_aesenclast_si128(t4, k12);
t1 = _mm_xor_si128(t1, d1);
t2 = _mm_xor_si128(t2, d2);
t3 = _mm_xor_si128(t3, d3);
t4 = _mm_xor_si128(t4, d4);
_mm_storeu_si128(bo + i + 0, t1);
_mm_storeu_si128(bo + i + 1, t2);
_mm_storeu_si128(bo + i + 2, t3);
_mm_storeu_si128(bo + i + 3, t4);
}
for (i = pblocks; i < blocks; i++)
{
d1 = _mm_loadu_si128(bi + i);
t1 = _mm_xor_si128(state, k0);
state = increment_be(state);
t1 = _mm_aesenc_si128(t1, k1);
t1 = _mm_aesenc_si128(t1, k2);
t1 = _mm_aesenc_si128(t1, k3);
t1 = _mm_aesenc_si128(t1, k4);
t1 = _mm_aesenc_si128(t1, k5);
t1 = _mm_aesenc_si128(t1, k6);
t1 = _mm_aesenc_si128(t1, k7);
t1 = _mm_aesenc_si128(t1, k8);
t1 = _mm_aesenc_si128(t1, k9);
t1 = _mm_aesenc_si128(t1, k10);
t1 = _mm_aesenc_si128(t1, k11);
t1 = _mm_aesenclast_si128(t1, k12);
t1 = _mm_xor_si128(t1, d1);
_mm_storeu_si128(bo + i, t1);
}
if (rem)
{
memset(&b, 0, sizeof(b));
memcpy(&b, bi + blocks, rem);
d1 = _mm_loadu_si128(&b);
t1 = _mm_xor_si128(state, k0);
t1 = _mm_aesenc_si128(t1, k1);
t1 = _mm_aesenc_si128(t1, k2);
t1 = _mm_aesenc_si128(t1, k3);
t1 = _mm_aesenc_si128(t1, k4);
t1 = _mm_aesenc_si128(t1, k5);
t1 = _mm_aesenc_si128(t1, k6);
t1 = _mm_aesenc_si128(t1, k7);
t1 = _mm_aesenc_si128(t1, k8);
t1 = _mm_aesenc_si128(t1, k9);
t1 = _mm_aesenc_si128(t1, k10);
t1 = _mm_aesenc_si128(t1, k11);
t1 = _mm_aesenclast_si128(t1, k12);
t1 = _mm_xor_si128(t1, d1);
_mm_storeu_si128(&b, t1);
memcpy(bo + blocks, &b, rem);
}
}
/**
* AES-256 CTR encryption
*/
static void encrypt_ctr256(private_aesni_ctr_t *this,
size_t len, u_char *in, u_char *out)
{
__m128i k0, k1, k2, k3, k4, k5, k6, k7, k8, k9, k10, k11, k12, k13, k14;
__m128i t1, t2, t3, t4;
__m128i d1, d2, d3, d4;
__m128i state, b, *bi, *bo;
u_int i, blocks, pblocks, rem;
state = _mm_load_si128((__m128i*)&this->state);
blocks = len / AES_BLOCK_SIZE;
pblocks = blocks - (blocks % CTR_CRYPT_PARALLELISM);
rem = len % AES_BLOCK_SIZE;
bi = (__m128i*)in;
bo = (__m128i*)out;
k0 = this->key->schedule[0];
k1 = this->key->schedule[1];
k2 = this->key->schedule[2];
k3 = this->key->schedule[3];
k4 = this->key->schedule[4];
k5 = this->key->schedule[5];
k6 = this->key->schedule[6];
k7 = this->key->schedule[7];
k8 = this->key->schedule[8];
k9 = this->key->schedule[9];
k10 = this->key->schedule[10];
k11 = this->key->schedule[11];
k12 = this->key->schedule[12];
k13 = this->key->schedule[13];
k14 = this->key->schedule[14];
for (i = 0; i < pblocks; i += CTR_CRYPT_PARALLELISM)
{
d1 = _mm_loadu_si128(bi + i + 0);
d2 = _mm_loadu_si128(bi + i + 1);
d3 = _mm_loadu_si128(bi + i + 2);
d4 = _mm_loadu_si128(bi + i + 3);
t1 = _mm_xor_si128(state, k0);
state = increment_be(state);
t2 = _mm_xor_si128(state, k0);
state = increment_be(state);
t3 = _mm_xor_si128(state, k0);
state = increment_be(state);
t4 = _mm_xor_si128(state, k0);
state = increment_be(state);
t1 = _mm_aesenc_si128(t1, k1);
t2 = _mm_aesenc_si128(t2, k1);
t3 = _mm_aesenc_si128(t3, k1);
t4 = _mm_aesenc_si128(t4, k1);
t1 = _mm_aesenc_si128(t1, k2);
t2 = _mm_aesenc_si128(t2, k2);
t3 = _mm_aesenc_si128(t3, k2);
t4 = _mm_aesenc_si128(t4, k2);
t1 = _mm_aesenc_si128(t1, k3);
t2 = _mm_aesenc_si128(t2, k3);
t3 = _mm_aesenc_si128(t3, k3);
t4 = _mm_aesenc_si128(t4, k3);
t1 = _mm_aesenc_si128(t1, k4);
t2 = _mm_aesenc_si128(t2, k4);
t3 = _mm_aesenc_si128(t3, k4);
t4 = _mm_aesenc_si128(t4, k4);
t1 = _mm_aesenc_si128(t1, k5);
t2 = _mm_aesenc_si128(t2, k5);
t3 = _mm_aesenc_si128(t3, k5);
t4 = _mm_aesenc_si128(t4, k5);
t1 = _mm_aesenc_si128(t1, k6);
t2 = _mm_aesenc_si128(t2, k6);
t3 = _mm_aesenc_si128(t3, k6);
t4 = _mm_aesenc_si128(t4, k6);
t1 = _mm_aesenc_si128(t1, k7);
t2 = _mm_aesenc_si128(t2, k7);
t3 = _mm_aesenc_si128(t3, k7);
t4 = _mm_aesenc_si128(t4, k7);
t1 = _mm_aesenc_si128(t1, k8);
t2 = _mm_aesenc_si128(t2, k8);
t3 = _mm_aesenc_si128(t3, k8);
t4 = _mm_aesenc_si128(t4, k8);
t1 = _mm_aesenc_si128(t1, k9);
t2 = _mm_aesenc_si128(t2, k9);
t3 = _mm_aesenc_si128(t3, k9);
t4 = _mm_aesenc_si128(t4, k9);
t1 = _mm_aesenc_si128(t1, k10);
t2 = _mm_aesenc_si128(t2, k10);
t3 = _mm_aesenc_si128(t3, k10);
t4 = _mm_aesenc_si128(t4, k10);
t1 = _mm_aesenc_si128(t1, k11);
t2 = _mm_aesenc_si128(t2, k11);
t3 = _mm_aesenc_si128(t3, k11);
t4 = _mm_aesenc_si128(t4, k11);
t1 = _mm_aesenc_si128(t1, k12);
t2 = _mm_aesenc_si128(t2, k12);
t3 = _mm_aesenc_si128(t3, k12);
t4 = _mm_aesenc_si128(t4, k12);
t1 = _mm_aesenc_si128(t1, k13);
t2 = _mm_aesenc_si128(t2, k13);
t3 = _mm_aesenc_si128(t3, k13);
t4 = _mm_aesenc_si128(t4, k13);
t1 = _mm_aesenclast_si128(t1, k14);
t2 = _mm_aesenclast_si128(t2, k14);
t3 = _mm_aesenclast_si128(t3, k14);
t4 = _mm_aesenclast_si128(t4, k14);
t1 = _mm_xor_si128(t1, d1);
t2 = _mm_xor_si128(t2, d2);
t3 = _mm_xor_si128(t3, d3);
t4 = _mm_xor_si128(t4, d4);
_mm_storeu_si128(bo + i + 0, t1);
_mm_storeu_si128(bo + i + 1, t2);
_mm_storeu_si128(bo + i + 2, t3);
_mm_storeu_si128(bo + i + 3, t4);
}
for (i = pblocks; i < blocks; i++)
{
d1 = _mm_loadu_si128(bi + i);
t1 = _mm_xor_si128(state, k0);
state = increment_be(state);
t1 = _mm_aesenc_si128(t1, k1);
t1 = _mm_aesenc_si128(t1, k2);
t1 = _mm_aesenc_si128(t1, k3);
t1 = _mm_aesenc_si128(t1, k4);
t1 = _mm_aesenc_si128(t1, k5);
t1 = _mm_aesenc_si128(t1, k6);
t1 = _mm_aesenc_si128(t1, k7);
t1 = _mm_aesenc_si128(t1, k8);
t1 = _mm_aesenc_si128(t1, k9);
t1 = _mm_aesenc_si128(t1, k10);
t1 = _mm_aesenc_si128(t1, k11);
t1 = _mm_aesenc_si128(t1, k12);
t1 = _mm_aesenc_si128(t1, k13);
t1 = _mm_aesenclast_si128(t1, k14);
t1 = _mm_xor_si128(t1, d1);
_mm_storeu_si128(bo + i, t1);
}
if (rem)
{
memset(&b, 0, sizeof(b));
memcpy(&b, bi + blocks, rem);
d1 = _mm_loadu_si128(&b);
t1 = _mm_xor_si128(state, k0);
t1 = _mm_aesenc_si128(t1, k1);
t1 = _mm_aesenc_si128(t1, k2);
t1 = _mm_aesenc_si128(t1, k3);
t1 = _mm_aesenc_si128(t1, k4);
t1 = _mm_aesenc_si128(t1, k5);
t1 = _mm_aesenc_si128(t1, k6);
t1 = _mm_aesenc_si128(t1, k7);
t1 = _mm_aesenc_si128(t1, k8);
t1 = _mm_aesenc_si128(t1, k9);
t1 = _mm_aesenc_si128(t1, k10);
t1 = _mm_aesenc_si128(t1, k11);
t1 = _mm_aesenc_si128(t1, k12);
t1 = _mm_aesenc_si128(t1, k13);
t1 = _mm_aesenclast_si128(t1, k14);
t1 = _mm_xor_si128(t1, d1);
_mm_storeu_si128(&b, t1);
memcpy(bo + blocks, &b, rem);
}
}
METHOD(crypter_t, crypt, bool,
private_aesni_ctr_t *this, chunk_t in, chunk_t iv, chunk_t *out)
{
u_char *buf;
if (!this->key || iv.len != sizeof(this->state.iv))
{
return FALSE;
}
memcpy(this->state.iv, iv.ptr, sizeof(this->state.iv));
this->state.counter = htonl(1);
buf = in.ptr;
if (out)
{
*out = chunk_alloc(in.len);
buf = out->ptr;
}
this->crypt(this, in.len, in.ptr, buf);
return TRUE;
}
METHOD(crypter_t, get_block_size, size_t,
private_aesni_ctr_t *this)
{
return 1;
}
METHOD(crypter_t, get_iv_size, size_t,
private_aesni_ctr_t *this)
{
return sizeof(this->state.iv);
}
METHOD(crypter_t, get_key_size, size_t,
private_aesni_ctr_t *this)
{
return this->key_size + sizeof(this->state.nonce);
}
METHOD(crypter_t, set_key, bool,
private_aesni_ctr_t *this, chunk_t key)
{
if (key.len != get_key_size(this))
{
return FALSE;
}
memcpy(this->state.nonce, key.ptr + key.len - sizeof(this->state.nonce),
sizeof(this->state.nonce));
key.len -= sizeof(this->state.nonce);
DESTROY_IF(this->key);
this->key = aesni_key_create(TRUE, key);
return this->key;
}
METHOD(crypter_t, destroy, void,
private_aesni_ctr_t *this)
{
DESTROY_IF(this->key);
free_align(this);
}
/**
* See header
*/
aesni_ctr_t *aesni_ctr_create(encryption_algorithm_t algo, size_t key_size)
{
private_aesni_ctr_t *this;
if (algo != ENCR_AES_CTR)
{
return NULL;
}
switch (key_size)
{
case 0:
key_size = 16;
break;
case 16:
case 24:
case 32:
break;
default:
return NULL;
}
INIT_ALIGN(this, sizeof(__m128i),
.public = {
.crypter = {
.encrypt = _crypt,
.decrypt = _crypt,
.get_block_size = _get_block_size,
.get_iv_size = _get_iv_size,
.get_key_size = _get_key_size,
.set_key = _set_key,
.destroy = _destroy,
},
},
.key_size = key_size,
);
switch (key_size)
{
case 16:
this->crypt = encrypt_ctr128;
break;
case 24:
this->crypt = encrypt_ctr192;
break;
case 32:
this->crypt = encrypt_ctr256;
break;
}
return &this->public;
}