https://github.com/torvalds/linux
Tip revision: 2595646791c319cadfdbf271563aac97d0843dc7 authored by Linus Torvalds on 02 December 2018, 23:07:55 UTC
Linux 4.20-rc5
Linux 4.20-rc5
Tip revision: 2595646
aegis128l.c
/*
* The AEGIS-128L Authenticated-Encryption Algorithm
*
* Copyright (c) 2017-2018 Ondrej Mosnacek <omosnacek@gmail.com>
* Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
*
* 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.
*/
#include <crypto/algapi.h>
#include <crypto/internal/aead.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include "aegis.h"
#define AEGIS128L_CHUNK_BLOCKS 2
#define AEGIS128L_CHUNK_SIZE (AEGIS128L_CHUNK_BLOCKS * AEGIS_BLOCK_SIZE)
#define AEGIS128L_NONCE_SIZE 16
#define AEGIS128L_STATE_BLOCKS 8
#define AEGIS128L_KEY_SIZE 16
#define AEGIS128L_MIN_AUTH_SIZE 8
#define AEGIS128L_MAX_AUTH_SIZE 16
union aegis_chunk {
union aegis_block blocks[AEGIS128L_CHUNK_BLOCKS];
u8 bytes[AEGIS128L_CHUNK_SIZE];
};
struct aegis_state {
union aegis_block blocks[AEGIS128L_STATE_BLOCKS];
};
struct aegis_ctx {
union aegis_block key;
};
struct aegis128l_ops {
int (*skcipher_walk_init)(struct skcipher_walk *walk,
struct aead_request *req, bool atomic);
void (*crypt_chunk)(struct aegis_state *state, u8 *dst,
const u8 *src, unsigned int size);
};
static void crypto_aegis128l_update(struct aegis_state *state)
{
union aegis_block tmp;
unsigned int i;
tmp = state->blocks[AEGIS128L_STATE_BLOCKS - 1];
for (i = AEGIS128L_STATE_BLOCKS - 1; i > 0; i--)
crypto_aegis_aesenc(&state->blocks[i], &state->blocks[i - 1],
&state->blocks[i]);
crypto_aegis_aesenc(&state->blocks[0], &tmp, &state->blocks[0]);
}
static void crypto_aegis128l_update_a(struct aegis_state *state,
const union aegis_chunk *msg)
{
crypto_aegis128l_update(state);
crypto_aegis_block_xor(&state->blocks[0], &msg->blocks[0]);
crypto_aegis_block_xor(&state->blocks[4], &msg->blocks[1]);
}
static void crypto_aegis128l_update_u(struct aegis_state *state,
const void *msg)
{
crypto_aegis128l_update(state);
crypto_xor(state->blocks[0].bytes, msg + 0 * AEGIS_BLOCK_SIZE,
AEGIS_BLOCK_SIZE);
crypto_xor(state->blocks[4].bytes, msg + 1 * AEGIS_BLOCK_SIZE,
AEGIS_BLOCK_SIZE);
}
static void crypto_aegis128l_init(struct aegis_state *state,
const union aegis_block *key,
const u8 *iv)
{
union aegis_block key_iv;
union aegis_chunk chunk;
unsigned int i;
memcpy(chunk.blocks[0].bytes, iv, AEGIS_BLOCK_SIZE);
chunk.blocks[1] = *key;
key_iv = *key;
crypto_aegis_block_xor(&key_iv, &chunk.blocks[0]);
state->blocks[0] = key_iv;
state->blocks[1] = crypto_aegis_const[1];
state->blocks[2] = crypto_aegis_const[0];
state->blocks[3] = crypto_aegis_const[1];
state->blocks[4] = key_iv;
state->blocks[5] = *key;
state->blocks[6] = *key;
state->blocks[7] = *key;
crypto_aegis_block_xor(&state->blocks[5], &crypto_aegis_const[0]);
crypto_aegis_block_xor(&state->blocks[6], &crypto_aegis_const[1]);
crypto_aegis_block_xor(&state->blocks[7], &crypto_aegis_const[0]);
for (i = 0; i < 10; i++) {
crypto_aegis128l_update_a(state, &chunk);
}
}
static void crypto_aegis128l_ad(struct aegis_state *state,
const u8 *src, unsigned int size)
{
if (AEGIS_ALIGNED(src)) {
const union aegis_chunk *src_chunk =
(const union aegis_chunk *)src;
while (size >= AEGIS128L_CHUNK_SIZE) {
crypto_aegis128l_update_a(state, src_chunk);
size -= AEGIS128L_CHUNK_SIZE;
src_chunk += 1;
}
} else {
while (size >= AEGIS128L_CHUNK_SIZE) {
crypto_aegis128l_update_u(state, src);
size -= AEGIS128L_CHUNK_SIZE;
src += AEGIS128L_CHUNK_SIZE;
}
}
}
static void crypto_aegis128l_encrypt_chunk(struct aegis_state *state, u8 *dst,
const u8 *src, unsigned int size)
{
union aegis_chunk tmp;
union aegis_block *tmp0 = &tmp.blocks[0];
union aegis_block *tmp1 = &tmp.blocks[1];
if (AEGIS_ALIGNED(src) && AEGIS_ALIGNED(dst)) {
while (size >= AEGIS128L_CHUNK_SIZE) {
union aegis_chunk *dst_blk =
(union aegis_chunk *)dst;
const union aegis_chunk *src_blk =
(const union aegis_chunk *)src;
*tmp0 = state->blocks[2];
crypto_aegis_block_and(tmp0, &state->blocks[3]);
crypto_aegis_block_xor(tmp0, &state->blocks[6]);
crypto_aegis_block_xor(tmp0, &state->blocks[1]);
crypto_aegis_block_xor(tmp0, &src_blk->blocks[0]);
*tmp1 = state->blocks[6];
crypto_aegis_block_and(tmp1, &state->blocks[7]);
crypto_aegis_block_xor(tmp1, &state->blocks[5]);
crypto_aegis_block_xor(tmp1, &state->blocks[2]);
crypto_aegis_block_xor(tmp1, &src_blk->blocks[1]);
crypto_aegis128l_update_a(state, src_blk);
*dst_blk = tmp;
size -= AEGIS128L_CHUNK_SIZE;
src += AEGIS128L_CHUNK_SIZE;
dst += AEGIS128L_CHUNK_SIZE;
}
} else {
while (size >= AEGIS128L_CHUNK_SIZE) {
*tmp0 = state->blocks[2];
crypto_aegis_block_and(tmp0, &state->blocks[3]);
crypto_aegis_block_xor(tmp0, &state->blocks[6]);
crypto_aegis_block_xor(tmp0, &state->blocks[1]);
crypto_xor(tmp0->bytes, src + 0 * AEGIS_BLOCK_SIZE,
AEGIS_BLOCK_SIZE);
*tmp1 = state->blocks[6];
crypto_aegis_block_and(tmp1, &state->blocks[7]);
crypto_aegis_block_xor(tmp1, &state->blocks[5]);
crypto_aegis_block_xor(tmp1, &state->blocks[2]);
crypto_xor(tmp1->bytes, src + 1 * AEGIS_BLOCK_SIZE,
AEGIS_BLOCK_SIZE);
crypto_aegis128l_update_u(state, src);
memcpy(dst, tmp.bytes, AEGIS128L_CHUNK_SIZE);
size -= AEGIS128L_CHUNK_SIZE;
src += AEGIS128L_CHUNK_SIZE;
dst += AEGIS128L_CHUNK_SIZE;
}
}
if (size > 0) {
union aegis_chunk msg = {};
memcpy(msg.bytes, src, size);
*tmp0 = state->blocks[2];
crypto_aegis_block_and(tmp0, &state->blocks[3]);
crypto_aegis_block_xor(tmp0, &state->blocks[6]);
crypto_aegis_block_xor(tmp0, &state->blocks[1]);
*tmp1 = state->blocks[6];
crypto_aegis_block_and(tmp1, &state->blocks[7]);
crypto_aegis_block_xor(tmp1, &state->blocks[5]);
crypto_aegis_block_xor(tmp1, &state->blocks[2]);
crypto_aegis128l_update_a(state, &msg);
crypto_aegis_block_xor(&msg.blocks[0], tmp0);
crypto_aegis_block_xor(&msg.blocks[1], tmp1);
memcpy(dst, msg.bytes, size);
}
}
static void crypto_aegis128l_decrypt_chunk(struct aegis_state *state, u8 *dst,
const u8 *src, unsigned int size)
{
union aegis_chunk tmp;
union aegis_block *tmp0 = &tmp.blocks[0];
union aegis_block *tmp1 = &tmp.blocks[1];
if (AEGIS_ALIGNED(src) && AEGIS_ALIGNED(dst)) {
while (size >= AEGIS128L_CHUNK_SIZE) {
union aegis_chunk *dst_blk =
(union aegis_chunk *)dst;
const union aegis_chunk *src_blk =
(const union aegis_chunk *)src;
*tmp0 = state->blocks[2];
crypto_aegis_block_and(tmp0, &state->blocks[3]);
crypto_aegis_block_xor(tmp0, &state->blocks[6]);
crypto_aegis_block_xor(tmp0, &state->blocks[1]);
crypto_aegis_block_xor(tmp0, &src_blk->blocks[0]);
*tmp1 = state->blocks[6];
crypto_aegis_block_and(tmp1, &state->blocks[7]);
crypto_aegis_block_xor(tmp1, &state->blocks[5]);
crypto_aegis_block_xor(tmp1, &state->blocks[2]);
crypto_aegis_block_xor(tmp1, &src_blk->blocks[1]);
crypto_aegis128l_update_a(state, &tmp);
*dst_blk = tmp;
size -= AEGIS128L_CHUNK_SIZE;
src += AEGIS128L_CHUNK_SIZE;
dst += AEGIS128L_CHUNK_SIZE;
}
} else {
while (size >= AEGIS128L_CHUNK_SIZE) {
*tmp0 = state->blocks[2];
crypto_aegis_block_and(tmp0, &state->blocks[3]);
crypto_aegis_block_xor(tmp0, &state->blocks[6]);
crypto_aegis_block_xor(tmp0, &state->blocks[1]);
crypto_xor(tmp0->bytes, src + 0 * AEGIS_BLOCK_SIZE,
AEGIS_BLOCK_SIZE);
*tmp1 = state->blocks[6];
crypto_aegis_block_and(tmp1, &state->blocks[7]);
crypto_aegis_block_xor(tmp1, &state->blocks[5]);
crypto_aegis_block_xor(tmp1, &state->blocks[2]);
crypto_xor(tmp1->bytes, src + 1 * AEGIS_BLOCK_SIZE,
AEGIS_BLOCK_SIZE);
crypto_aegis128l_update_a(state, &tmp);
memcpy(dst, tmp.bytes, AEGIS128L_CHUNK_SIZE);
size -= AEGIS128L_CHUNK_SIZE;
src += AEGIS128L_CHUNK_SIZE;
dst += AEGIS128L_CHUNK_SIZE;
}
}
if (size > 0) {
union aegis_chunk msg = {};
memcpy(msg.bytes, src, size);
*tmp0 = state->blocks[2];
crypto_aegis_block_and(tmp0, &state->blocks[3]);
crypto_aegis_block_xor(tmp0, &state->blocks[6]);
crypto_aegis_block_xor(tmp0, &state->blocks[1]);
crypto_aegis_block_xor(&msg.blocks[0], tmp0);
*tmp1 = state->blocks[6];
crypto_aegis_block_and(tmp1, &state->blocks[7]);
crypto_aegis_block_xor(tmp1, &state->blocks[5]);
crypto_aegis_block_xor(tmp1, &state->blocks[2]);
crypto_aegis_block_xor(&msg.blocks[1], tmp1);
memset(msg.bytes + size, 0, AEGIS128L_CHUNK_SIZE - size);
crypto_aegis128l_update_a(state, &msg);
memcpy(dst, msg.bytes, size);
}
}
static void crypto_aegis128l_process_ad(struct aegis_state *state,
struct scatterlist *sg_src,
unsigned int assoclen)
{
struct scatter_walk walk;
union aegis_chunk buf;
unsigned int pos = 0;
scatterwalk_start(&walk, sg_src);
while (assoclen != 0) {
unsigned int size = scatterwalk_clamp(&walk, assoclen);
unsigned int left = size;
void *mapped = scatterwalk_map(&walk);
const u8 *src = (const u8 *)mapped;
if (pos + size >= AEGIS128L_CHUNK_SIZE) {
if (pos > 0) {
unsigned int fill = AEGIS128L_CHUNK_SIZE - pos;
memcpy(buf.bytes + pos, src, fill);
crypto_aegis128l_update_a(state, &buf);
pos = 0;
left -= fill;
src += fill;
}
crypto_aegis128l_ad(state, src, left);
src += left & ~(AEGIS128L_CHUNK_SIZE - 1);
left &= AEGIS128L_CHUNK_SIZE - 1;
}
memcpy(buf.bytes + pos, src, left);
pos += left;
assoclen -= size;
scatterwalk_unmap(mapped);
scatterwalk_advance(&walk, size);
scatterwalk_done(&walk, 0, assoclen);
}
if (pos > 0) {
memset(buf.bytes + pos, 0, AEGIS128L_CHUNK_SIZE - pos);
crypto_aegis128l_update_a(state, &buf);
}
}
static void crypto_aegis128l_process_crypt(struct aegis_state *state,
struct aead_request *req,
const struct aegis128l_ops *ops)
{
struct skcipher_walk walk;
u8 *src, *dst;
unsigned int chunksize;
ops->skcipher_walk_init(&walk, req, false);
while (walk.nbytes) {
src = walk.src.virt.addr;
dst = walk.dst.virt.addr;
chunksize = walk.nbytes;
ops->crypt_chunk(state, dst, src, chunksize);
skcipher_walk_done(&walk, 0);
}
}
static void crypto_aegis128l_final(struct aegis_state *state,
union aegis_block *tag_xor,
u64 assoclen, u64 cryptlen)
{
u64 assocbits = assoclen * 8;
u64 cryptbits = cryptlen * 8;
union aegis_chunk tmp;
unsigned int i;
tmp.blocks[0].words64[0] = cpu_to_le64(assocbits);
tmp.blocks[0].words64[1] = cpu_to_le64(cryptbits);
crypto_aegis_block_xor(&tmp.blocks[0], &state->blocks[2]);
tmp.blocks[1] = tmp.blocks[0];
for (i = 0; i < 7; i++)
crypto_aegis128l_update_a(state, &tmp);
for (i = 0; i < 7; i++)
crypto_aegis_block_xor(tag_xor, &state->blocks[i]);
}
static int crypto_aegis128l_setkey(struct crypto_aead *aead, const u8 *key,
unsigned int keylen)
{
struct aegis_ctx *ctx = crypto_aead_ctx(aead);
if (keylen != AEGIS128L_KEY_SIZE) {
crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
return -EINVAL;
}
memcpy(ctx->key.bytes, key, AEGIS128L_KEY_SIZE);
return 0;
}
static int crypto_aegis128l_setauthsize(struct crypto_aead *tfm,
unsigned int authsize)
{
if (authsize > AEGIS128L_MAX_AUTH_SIZE)
return -EINVAL;
if (authsize < AEGIS128L_MIN_AUTH_SIZE)
return -EINVAL;
return 0;
}
static void crypto_aegis128l_crypt(struct aead_request *req,
union aegis_block *tag_xor,
unsigned int cryptlen,
const struct aegis128l_ops *ops)
{
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
struct aegis_state state;
crypto_aegis128l_init(&state, &ctx->key, req->iv);
crypto_aegis128l_process_ad(&state, req->src, req->assoclen);
crypto_aegis128l_process_crypt(&state, req, ops);
crypto_aegis128l_final(&state, tag_xor, req->assoclen, cryptlen);
}
static int crypto_aegis128l_encrypt(struct aead_request *req)
{
static const struct aegis128l_ops ops = {
.skcipher_walk_init = skcipher_walk_aead_encrypt,
.crypt_chunk = crypto_aegis128l_encrypt_chunk,
};
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
union aegis_block tag = {};
unsigned int authsize = crypto_aead_authsize(tfm);
unsigned int cryptlen = req->cryptlen;
crypto_aegis128l_crypt(req, &tag, cryptlen, &ops);
scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen,
authsize, 1);
return 0;
}
static int crypto_aegis128l_decrypt(struct aead_request *req)
{
static const struct aegis128l_ops ops = {
.skcipher_walk_init = skcipher_walk_aead_decrypt,
.crypt_chunk = crypto_aegis128l_decrypt_chunk,
};
static const u8 zeros[AEGIS128L_MAX_AUTH_SIZE] = {};
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
union aegis_block tag;
unsigned int authsize = crypto_aead_authsize(tfm);
unsigned int cryptlen = req->cryptlen - authsize;
scatterwalk_map_and_copy(tag.bytes, req->src, req->assoclen + cryptlen,
authsize, 0);
crypto_aegis128l_crypt(req, &tag, cryptlen, &ops);
return crypto_memneq(tag.bytes, zeros, authsize) ? -EBADMSG : 0;
}
static int crypto_aegis128l_init_tfm(struct crypto_aead *tfm)
{
return 0;
}
static void crypto_aegis128l_exit_tfm(struct crypto_aead *tfm)
{
}
static struct aead_alg crypto_aegis128l_alg = {
.setkey = crypto_aegis128l_setkey,
.setauthsize = crypto_aegis128l_setauthsize,
.encrypt = crypto_aegis128l_encrypt,
.decrypt = crypto_aegis128l_decrypt,
.init = crypto_aegis128l_init_tfm,
.exit = crypto_aegis128l_exit_tfm,
.ivsize = AEGIS128L_NONCE_SIZE,
.maxauthsize = AEGIS128L_MAX_AUTH_SIZE,
.chunksize = AEGIS128L_CHUNK_SIZE,
.base = {
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct aegis_ctx),
.cra_alignmask = 0,
.cra_priority = 100,
.cra_name = "aegis128l",
.cra_driver_name = "aegis128l-generic",
.cra_module = THIS_MODULE,
}
};
static int __init crypto_aegis128l_module_init(void)
{
return crypto_register_aead(&crypto_aegis128l_alg);
}
static void __exit crypto_aegis128l_module_exit(void)
{
crypto_unregister_aead(&crypto_aegis128l_alg);
}
module_init(crypto_aegis128l_module_init);
module_exit(crypto_aegis128l_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
MODULE_DESCRIPTION("AEGIS-128L AEAD algorithm");
MODULE_ALIAS_CRYPTO("aegis128l");
MODULE_ALIAS_CRYPTO("aegis128l-generic");