#include <crypto/internal/aead.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
#include <linux/module.h>
#include <asm/fpu/api.h>
#include <asm/cpu_device_id.h>
#define AEGIS128_BLOCK_ALIGN 16
#define AEGIS128_BLOCK_SIZE 16
#define AEGIS128_NONCE_SIZE 16
#define AEGIS128_STATE_BLOCKS 5
#define AEGIS128_KEY_SIZE 16
#define AEGIS128_MIN_AUTH_SIZE 8
#define AEGIS128_MAX_AUTH_SIZE 16
struct aegis_block {
u8 bytes[AEGIS128_BLOCK_SIZE] __aligned(AEGIS128_BLOCK_ALIGN);
};
struct aegis_state {
struct aegis_block blocks[AEGIS128_STATE_BLOCKS];
};
struct aegis_ctx {
struct aegis_block key;
};
asmlinkage void aegis128_aesni_init(struct aegis_state *state,
const struct aegis_block *key,
const u8 iv[AEGIS128_NONCE_SIZE]);
asmlinkage void aegis128_aesni_ad(struct aegis_state *state, const u8 *data,
unsigned int len);
asmlinkage void aegis128_aesni_enc(struct aegis_state *state, const u8 *src,
u8 *dst, unsigned int len);
asmlinkage void aegis128_aesni_dec(struct aegis_state *state, const u8 *src,
u8 *dst, unsigned int len);
asmlinkage void aegis128_aesni_enc_tail(struct aegis_state *state,
const u8 *src, u8 *dst,
unsigned int len);
asmlinkage void aegis128_aesni_dec_tail(struct aegis_state *state,
const u8 *src, u8 *dst,
unsigned int len);
asmlinkage void aegis128_aesni_final(struct aegis_state *state,
struct aegis_block *tag_xor,
unsigned int assoclen,
unsigned int cryptlen);
static void crypto_aegis128_aesni_process_ad(
struct aegis_state *state, struct scatterlist *sg_src,
unsigned int assoclen)
{
struct scatter_walk walk;
struct aegis_block buf;
unsigned int pos = 0;
scatterwalk_start(&walk, sg_src);
while (assoclen != 0) {
unsigned int size = scatterwalk_next(&walk, assoclen);
const u8 *src = walk.addr;
unsigned int left = size;
if (pos + size >= AEGIS128_BLOCK_SIZE) {
if (pos > 0) {
unsigned int fill = AEGIS128_BLOCK_SIZE - pos;
memcpy(buf.bytes + pos, src, fill);
aegis128_aesni_ad(state, buf.bytes,
AEGIS128_BLOCK_SIZE);
pos = 0;
left -= fill;
src += fill;
}
aegis128_aesni_ad(state, src,
left & ~(AEGIS128_BLOCK_SIZE - 1));
src += left & ~(AEGIS128_BLOCK_SIZE - 1);
left &= AEGIS128_BLOCK_SIZE - 1;
}
memcpy(buf.bytes + pos, src, left);
pos += left;
assoclen -= size;
scatterwalk_done_src(&walk, size);
}
if (pos > 0) {
memset(buf.bytes + pos, 0, AEGIS128_BLOCK_SIZE - pos);
aegis128_aesni_ad(state, buf.bytes, AEGIS128_BLOCK_SIZE);
}
}
static __always_inline int
crypto_aegis128_aesni_process_crypt(struct aegis_state *state,
struct skcipher_walk *walk, bool enc)
{
int err = 0;
while (walk->nbytes >= AEGIS128_BLOCK_SIZE) {
if (enc)
aegis128_aesni_enc(state, walk->src.virt.addr,
walk->dst.virt.addr,
round_down(walk->nbytes,
AEGIS128_BLOCK_SIZE));
else
aegis128_aesni_dec(state, walk->src.virt.addr,
walk->dst.virt.addr,
round_down(walk->nbytes,
AEGIS128_BLOCK_SIZE));
kernel_fpu_end();
err = skcipher_walk_done(walk,
walk->nbytes % AEGIS128_BLOCK_SIZE);
kernel_fpu_begin();
}
if (walk->nbytes) {
if (enc)
aegis128_aesni_enc_tail(state, walk->src.virt.addr,
walk->dst.virt.addr,
walk->nbytes);
else
aegis128_aesni_dec_tail(state, walk->src.virt.addr,
walk->dst.virt.addr,
walk->nbytes);
kernel_fpu_end();
err = skcipher_walk_done(walk, 0);
kernel_fpu_begin();
}
return err;
}
static struct aegis_ctx *crypto_aegis128_aesni_ctx(struct crypto_aead *aead)
{
u8 *ctx = crypto_aead_ctx(aead);
ctx = PTR_ALIGN(ctx, __alignof__(struct aegis_ctx));
return (void *)ctx;
}
static int crypto_aegis128_aesni_setkey(struct crypto_aead *aead, const u8 *key,
unsigned int keylen)
{
struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(aead);
if (keylen != AEGIS128_KEY_SIZE)
return -EINVAL;
memcpy(ctx->key.bytes, key, AEGIS128_KEY_SIZE);
return 0;
}
static int crypto_aegis128_aesni_setauthsize(struct crypto_aead *tfm,
unsigned int authsize)
{
if (authsize > AEGIS128_MAX_AUTH_SIZE)
return -EINVAL;
if (authsize < AEGIS128_MIN_AUTH_SIZE)
return -EINVAL;
return 0;
}
static __always_inline int
crypto_aegis128_aesni_crypt(struct aead_request *req,
struct aegis_block *tag_xor,
unsigned int cryptlen, bool enc)
{
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(tfm);
struct skcipher_walk walk;
struct aegis_state state;
int err;
if (enc)
err = skcipher_walk_aead_encrypt(&walk, req, false);
else
err = skcipher_walk_aead_decrypt(&walk, req, false);
if (err)
return err;
kernel_fpu_begin();
aegis128_aesni_init(&state, &ctx->key, req->iv);
crypto_aegis128_aesni_process_ad(&state, req->src, req->assoclen);
err = crypto_aegis128_aesni_process_crypt(&state, &walk, enc);
if (err == 0)
aegis128_aesni_final(&state, tag_xor, req->assoclen, cryptlen);
kernel_fpu_end();
return err;
}
static int crypto_aegis128_aesni_encrypt(struct aead_request *req)
{
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
struct aegis_block tag = {};
unsigned int authsize = crypto_aead_authsize(tfm);
unsigned int cryptlen = req->cryptlen;
int err;
err = crypto_aegis128_aesni_crypt(req, &tag, cryptlen, true);
if (err)
return err;
scatterwalk_map_and_copy(tag.bytes, req->dst,
req->assoclen + cryptlen, authsize, 1);
return 0;
}
static int crypto_aegis128_aesni_decrypt(struct aead_request *req)
{
static const struct aegis_block zeros = {};
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
struct aegis_block tag;
unsigned int authsize = crypto_aead_authsize(tfm);
unsigned int cryptlen = req->cryptlen - authsize;
int err;
scatterwalk_map_and_copy(tag.bytes, req->src,
req->assoclen + cryptlen, authsize, 0);
err = crypto_aegis128_aesni_crypt(req, &tag, cryptlen, false);
if (err)
return err;
return crypto_memneq(tag.bytes, zeros.bytes, authsize) ? -EBADMSG : 0;
}
static struct aead_alg crypto_aegis128_aesni_alg = {
.setkey = crypto_aegis128_aesni_setkey,
.setauthsize = crypto_aegis128_aesni_setauthsize,
.encrypt = crypto_aegis128_aesni_encrypt,
.decrypt = crypto_aegis128_aesni_decrypt,
.ivsize = AEGIS128_NONCE_SIZE,
.maxauthsize = AEGIS128_MAX_AUTH_SIZE,
.chunksize = AEGIS128_BLOCK_SIZE,
.base = {
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct aegis_ctx) +
__alignof__(struct aegis_ctx),
.cra_priority = 400,
.cra_name = "aegis128",
.cra_driver_name = "aegis128-aesni",
.cra_module = THIS_MODULE,
}
};
static int __init crypto_aegis128_aesni_module_init(void)
{
if (!boot_cpu_has(X86_FEATURE_XMM4_1) ||
!boot_cpu_has(X86_FEATURE_AES) ||
!cpu_has_xfeatures(XFEATURE_MASK_SSE, NULL))
return -ENODEV;
return crypto_register_aead(&crypto_aegis128_aesni_alg);
}
static void __exit crypto_aegis128_aesni_module_exit(void)
{
crypto_unregister_aead(&crypto_aegis128_aesni_alg);
}
module_init(crypto_aegis128_aesni_module_init);
module_exit(crypto_aegis128_aesni_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm -- AESNI+SSE4.1 implementation");
MODULE_ALIAS_CRYPTO("aegis128");
MODULE_ALIAS_CRYPTO("aegis128-aesni");
