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author | Ondrej Mosnacek <omosnacek@gmail.com> | 2018-05-11 14:12:49 +0200 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2018-05-18 18:13:58 +0200 |
commit | f606a88e58230c30f5d56a53eff8da6fdbf1e4ee (patch) | |
tree | 18c37d9d32d953978f5e88ed0ee8b414afa50b05 /crypto/aegis256.c | |
parent | crypto: testmgr - reorder paes test lexicographically (diff) | |
download | linux-f606a88e58230c30f5d56a53eff8da6fdbf1e4ee.tar.xz linux-f606a88e58230c30f5d56a53eff8da6fdbf1e4ee.zip |
crypto: aegis - Add generic AEGIS AEAD implementations
This patch adds the generic implementation of the AEGIS family of AEAD
algorithms (AEGIS-128, AEGIS-128L, and AEGIS-256). The original
authors of AEGIS are Hongjun Wu and Bart Preneel.
At the time of writing, AEGIS is one of the finalists in CAESAR, an
open competition intended to select a portfolio of alternatives to
the problematic AES-GCM:
https://competitions.cr.yp.to/caesar-submissions.html
https://competitions.cr.yp.to/round3/aegisv11.pdf
Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/aegis256.c')
-rw-r--r-- | crypto/aegis256.c | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/crypto/aegis256.c b/crypto/aegis256.c new file mode 100644 index 000000000000..a489d741d33a --- /dev/null +++ b/crypto/aegis256.c @@ -0,0 +1,478 @@ +/* + * The AEGIS-256 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 AEGIS256_NONCE_SIZE 32 +#define AEGIS256_STATE_BLOCKS 6 +#define AEGIS256_KEY_SIZE 32 +#define AEGIS256_MIN_AUTH_SIZE 8 +#define AEGIS256_MAX_AUTH_SIZE 16 + +struct aegis_state { + union aegis_block blocks[AEGIS256_STATE_BLOCKS]; +}; + +struct aegis_ctx { + union aegis_block key[AEGIS256_KEY_SIZE / AEGIS_BLOCK_SIZE]; +}; + +struct aegis256_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_aegis256_update(struct aegis_state *state) +{ + union aegis_block tmp; + unsigned int i; + + tmp = state->blocks[AEGIS256_STATE_BLOCKS - 1]; + for (i = AEGIS256_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_aegis256_update_a(struct aegis_state *state, + const union aegis_block *msg) +{ + crypto_aegis256_update(state); + crypto_aegis_block_xor(&state->blocks[0], msg); +} + +static void crypto_aegis256_update_u(struct aegis_state *state, const void *msg) +{ + crypto_aegis256_update(state); + crypto_xor(state->blocks[0].bytes, msg, AEGIS_BLOCK_SIZE); +} + +static void crypto_aegis256_init(struct aegis_state *state, + const union aegis_block *key, + const u8 *iv) +{ + union aegis_block key_iv[2]; + unsigned int i; + + key_iv[0] = key[0]; + key_iv[1] = key[1]; + crypto_xor(key_iv[0].bytes, iv + 0 * AEGIS_BLOCK_SIZE, + AEGIS_BLOCK_SIZE); + crypto_xor(key_iv[1].bytes, iv + 1 * AEGIS_BLOCK_SIZE, + AEGIS_BLOCK_SIZE); + + state->blocks[0] = key_iv[0]; + state->blocks[1] = key_iv[1]; + state->blocks[2] = crypto_aegis_const[1]; + state->blocks[3] = crypto_aegis_const[0]; + state->blocks[4] = key[0]; + state->blocks[5] = key[1]; + + crypto_aegis_block_xor(&state->blocks[4], &crypto_aegis_const[0]); + crypto_aegis_block_xor(&state->blocks[5], &crypto_aegis_const[1]); + + for (i = 0; i < 4; i++) { + crypto_aegis256_update_a(state, &key[0]); + crypto_aegis256_update_a(state, &key[1]); + crypto_aegis256_update_a(state, &key_iv[0]); + crypto_aegis256_update_a(state, &key_iv[1]); + } +} + +static void crypto_aegis256_ad(struct aegis_state *state, + const u8 *src, unsigned int size) +{ + if (AEGIS_ALIGNED(src)) { + const union aegis_block *src_blk = + (const union aegis_block *)src; + + while (size >= AEGIS_BLOCK_SIZE) { + crypto_aegis256_update_a(state, src_blk); + + size -= AEGIS_BLOCK_SIZE; + src_blk++; + } + } else { + while (size >= AEGIS_BLOCK_SIZE) { + crypto_aegis256_update_u(state, src); + + size -= AEGIS_BLOCK_SIZE; + src += AEGIS_BLOCK_SIZE; + } + } +} + +static void crypto_aegis256_encrypt_chunk(struct aegis_state *state, u8 *dst, + const u8 *src, unsigned int size) +{ + union aegis_block tmp; + + if (AEGIS_ALIGNED(src) && AEGIS_ALIGNED(dst)) { + while (size >= AEGIS_BLOCK_SIZE) { + union aegis_block *dst_blk = + (union aegis_block *)dst; + const union aegis_block *src_blk = + (const union aegis_block *)src; + + tmp = state->blocks[2]; + crypto_aegis_block_and(&tmp, &state->blocks[3]); + crypto_aegis_block_xor(&tmp, &state->blocks[5]); + crypto_aegis_block_xor(&tmp, &state->blocks[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_aegis_block_xor(&tmp, src_blk); + + crypto_aegis256_update_a(state, src_blk); + + *dst_blk = tmp; + + size -= AEGIS_BLOCK_SIZE; + src += AEGIS_BLOCK_SIZE; + dst += AEGIS_BLOCK_SIZE; + } + } else { + while (size >= AEGIS_BLOCK_SIZE) { + tmp = state->blocks[2]; + crypto_aegis_block_and(&tmp, &state->blocks[3]); + crypto_aegis_block_xor(&tmp, &state->blocks[5]); + crypto_aegis_block_xor(&tmp, &state->blocks[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_xor(tmp.bytes, src, AEGIS_BLOCK_SIZE); + + crypto_aegis256_update_u(state, src); + + memcpy(dst, tmp.bytes, AEGIS_BLOCK_SIZE); + + size -= AEGIS_BLOCK_SIZE; + src += AEGIS_BLOCK_SIZE; + dst += AEGIS_BLOCK_SIZE; + } + } + + if (size > 0) { + union aegis_block msg = {}; + memcpy(msg.bytes, src, size); + + tmp = state->blocks[2]; + crypto_aegis_block_and(&tmp, &state->blocks[3]); + crypto_aegis_block_xor(&tmp, &state->blocks[5]); + crypto_aegis_block_xor(&tmp, &state->blocks[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + + crypto_aegis256_update_a(state, &msg); + + crypto_aegis_block_xor(&msg, &tmp); + + memcpy(dst, msg.bytes, size); + } +} + +static void crypto_aegis256_decrypt_chunk(struct aegis_state *state, u8 *dst, + const u8 *src, unsigned int size) +{ + union aegis_block tmp; + + if (AEGIS_ALIGNED(src) && AEGIS_ALIGNED(dst)) { + while (size >= AEGIS_BLOCK_SIZE) { + union aegis_block *dst_blk = + (union aegis_block *)dst; + const union aegis_block *src_blk = + (const union aegis_block *)src; + + tmp = state->blocks[2]; + crypto_aegis_block_and(&tmp, &state->blocks[3]); + crypto_aegis_block_xor(&tmp, &state->blocks[5]); + crypto_aegis_block_xor(&tmp, &state->blocks[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_aegis_block_xor(&tmp, src_blk); + + crypto_aegis256_update_a(state, &tmp); + + *dst_blk = tmp; + + size -= AEGIS_BLOCK_SIZE; + src += AEGIS_BLOCK_SIZE; + dst += AEGIS_BLOCK_SIZE; + } + } else { + while (size >= AEGIS_BLOCK_SIZE) { + tmp = state->blocks[2]; + crypto_aegis_block_and(&tmp, &state->blocks[3]); + crypto_aegis_block_xor(&tmp, &state->blocks[5]); + crypto_aegis_block_xor(&tmp, &state->blocks[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_xor(tmp.bytes, src, AEGIS_BLOCK_SIZE); + + crypto_aegis256_update_a(state, &tmp); + + memcpy(dst, tmp.bytes, AEGIS_BLOCK_SIZE); + + size -= AEGIS_BLOCK_SIZE; + src += AEGIS_BLOCK_SIZE; + dst += AEGIS_BLOCK_SIZE; + } + } + + if (size > 0) { + union aegis_block msg = {}; + memcpy(msg.bytes, src, size); + + tmp = state->blocks[2]; + crypto_aegis_block_and(&tmp, &state->blocks[3]); + crypto_aegis_block_xor(&tmp, &state->blocks[5]); + crypto_aegis_block_xor(&tmp, &state->blocks[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_aegis_block_xor(&msg, &tmp); + + memset(msg.bytes + size, 0, AEGIS_BLOCK_SIZE - size); + + crypto_aegis256_update_a(state, &msg); + + memcpy(dst, msg.bytes, size); + } +} + +static void crypto_aegis256_process_ad(struct aegis_state *state, + struct scatterlist *sg_src, + unsigned int assoclen) +{ + struct scatter_walk walk; + union aegis_block 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 >= AEGIS_BLOCK_SIZE) { + if (pos > 0) { + unsigned int fill = AEGIS_BLOCK_SIZE - pos; + memcpy(buf.bytes + pos, src, fill); + crypto_aegis256_update_a(state, &buf); + pos = 0; + left -= fill; + src += fill; + } + + crypto_aegis256_ad(state, src, left); + src += left & ~(AEGIS_BLOCK_SIZE - 1); + left &= AEGIS_BLOCK_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, AEGIS_BLOCK_SIZE - pos); + crypto_aegis256_update_a(state, &buf); + } +} + +static void crypto_aegis256_process_crypt(struct aegis_state *state, + struct aead_request *req, + const struct aegis256_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_aegis256_final(struct aegis_state *state, + union aegis_block *tag_xor, + u64 assoclen, u64 cryptlen) +{ + u64 assocbits = assoclen * 8; + u64 cryptbits = cryptlen * 8; + + union aegis_block tmp; + unsigned int i; + + tmp.words64[0] = cpu_to_le64(assocbits); + tmp.words64[1] = cpu_to_le64(cryptbits); + + crypto_aegis_block_xor(&tmp, &state->blocks[3]); + + for (i = 0; i < 7; i++) + crypto_aegis256_update_a(state, &tmp); + + for (i = 0; i < AEGIS256_STATE_BLOCKS; i++) + crypto_aegis_block_xor(tag_xor, &state->blocks[i]); +} + +static int crypto_aegis256_setkey(struct crypto_aead *aead, const u8 *key, + unsigned int keylen) +{ + struct aegis_ctx *ctx = crypto_aead_ctx(aead); + + if (keylen != AEGIS256_KEY_SIZE) { + crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN); + return -EINVAL; + } + + memcpy(ctx->key[0].bytes, key, AEGIS_BLOCK_SIZE); + memcpy(ctx->key[1].bytes, key + AEGIS_BLOCK_SIZE, + AEGIS_BLOCK_SIZE); + return 0; +} + +static int crypto_aegis256_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + if (authsize > AEGIS256_MAX_AUTH_SIZE) + return -EINVAL; + if (authsize < AEGIS256_MIN_AUTH_SIZE) + return -EINVAL; + return 0; +} + +static void crypto_aegis256_crypt(struct aead_request *req, + union aegis_block *tag_xor, + unsigned int cryptlen, + const struct aegis256_ops *ops) +{ + struct crypto_aead *tfm = crypto_aead_reqtfm(req); + struct aegis_ctx *ctx = crypto_aead_ctx(tfm); + struct aegis_state state; + + crypto_aegis256_init(&state, ctx->key, req->iv); + crypto_aegis256_process_ad(&state, req->src, req->assoclen); + crypto_aegis256_process_crypt(&state, req, ops); + crypto_aegis256_final(&state, tag_xor, req->assoclen, cryptlen); +} + +static int crypto_aegis256_encrypt(struct aead_request *req) +{ + static const struct aegis256_ops ops = { + .skcipher_walk_init = skcipher_walk_aead_encrypt, + .crypt_chunk = crypto_aegis256_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_aegis256_crypt(req, &tag, cryptlen, &ops); + + scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen, + authsize, 1); + return 0; +} + +static int crypto_aegis256_decrypt(struct aead_request *req) +{ + static const struct aegis256_ops ops = { + .skcipher_walk_init = skcipher_walk_aead_decrypt, + .crypt_chunk = crypto_aegis256_decrypt_chunk, + }; + static const u8 zeros[AEGIS256_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_aegis256_crypt(req, &tag, cryptlen, &ops); + + return crypto_memneq(tag.bytes, zeros, authsize) ? -EBADMSG : 0; +} + +static int crypto_aegis256_init_tfm(struct crypto_aead *tfm) +{ + return 0; +} + +static void crypto_aegis256_exit_tfm(struct crypto_aead *tfm) +{ +} + +static struct aead_alg crypto_aegis256_alg = { + .setkey = crypto_aegis256_setkey, + .setauthsize = crypto_aegis256_setauthsize, + .encrypt = crypto_aegis256_encrypt, + .decrypt = crypto_aegis256_decrypt, + .init = crypto_aegis256_init_tfm, + .exit = crypto_aegis256_exit_tfm, + + .ivsize = AEGIS256_NONCE_SIZE, + .maxauthsize = AEGIS256_MAX_AUTH_SIZE, + .chunksize = AEGIS_BLOCK_SIZE, + + .base = { + .cra_flags = CRYPTO_ALG_TYPE_AEAD, + .cra_blocksize = 1, + .cra_ctxsize = sizeof(struct aegis_ctx), + .cra_alignmask = 0, + + .cra_priority = 100, + + .cra_name = "aegis256", + .cra_driver_name = "aegis256-generic", + + .cra_module = THIS_MODULE, + } +}; + +static int __init crypto_aegis256_module_init(void) +{ + return crypto_register_aead(&crypto_aegis256_alg); +} + +static void __exit crypto_aegis256_module_exit(void) +{ + crypto_unregister_aead(&crypto_aegis256_alg); +} + +module_init(crypto_aegis256_module_init); +module_exit(crypto_aegis256_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>"); +MODULE_DESCRIPTION("AEGIS-256 AEAD algorithm"); +MODULE_ALIAS_CRYPTO("aegis256"); +MODULE_ALIAS_CRYPTO("aegis256-generic"); |