diff options
Diffstat (limited to 'crypto/aegis128-core.c')
| -rw-r--r-- | crypto/aegis128-core.c | 581 |
1 files changed, 581 insertions, 0 deletions
diff --git a/crypto/aegis128-core.c b/crypto/aegis128-core.c new file mode 100644 index 000000000..c4f1bfa1d --- /dev/null +++ b/crypto/aegis128-core.c @@ -0,0 +1,581 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * The AEGIS-128 Authenticated-Encryption Algorithm + * + * Copyright (c) 2017-2018 Ondrej Mosnacek <omosnacek@gmail.com> + * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved. + */ + +#include <crypto/algapi.h> +#include <crypto/internal/aead.h> +#include <crypto/internal/simd.h> +#include <crypto/internal/skcipher.h> +#include <crypto/scatterwalk.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/jump_label.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/scatterlist.h> + +#include <asm/simd.h> + +#include "aegis.h" + +#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_state { + union aegis_block blocks[AEGIS128_STATE_BLOCKS]; +}; + +struct aegis_ctx { + union aegis_block key; +}; + +static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_simd); + +static const union aegis_block crypto_aegis_const[2] = { + { .words64 = { + cpu_to_le64(U64_C(0x0d08050302010100)), + cpu_to_le64(U64_C(0x6279e99059372215)), + } }, + { .words64 = { + cpu_to_le64(U64_C(0xf12fc26d55183ddb)), + cpu_to_le64(U64_C(0xdd28b57342311120)), + } }, +}; + +static bool aegis128_do_simd(void) +{ +#ifdef CONFIG_CRYPTO_AEGIS128_SIMD + if (static_branch_likely(&have_simd)) + return crypto_simd_usable(); +#endif + return false; +} + +static void crypto_aegis128_update(struct aegis_state *state) +{ + union aegis_block tmp; + unsigned int i; + + tmp = state->blocks[AEGIS128_STATE_BLOCKS - 1]; + for (i = AEGIS128_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_aegis128_update_a(struct aegis_state *state, + const union aegis_block *msg, + bool do_simd) +{ + if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) && do_simd) { + crypto_aegis128_update_simd(state, msg); + return; + } + + crypto_aegis128_update(state); + crypto_aegis_block_xor(&state->blocks[0], msg); +} + +static void crypto_aegis128_update_u(struct aegis_state *state, const void *msg, + bool do_simd) +{ + if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) && do_simd) { + crypto_aegis128_update_simd(state, msg); + return; + } + + crypto_aegis128_update(state); + crypto_xor(state->blocks[0].bytes, msg, AEGIS_BLOCK_SIZE); +} + +static void crypto_aegis128_init(struct aegis_state *state, + const union aegis_block *key, + const u8 *iv) +{ + union aegis_block key_iv; + unsigned int i; + + key_iv = *key; + crypto_xor(key_iv.bytes, iv, AEGIS_BLOCK_SIZE); + + state->blocks[0] = key_iv; + state->blocks[1] = crypto_aegis_const[1]; + state->blocks[2] = crypto_aegis_const[0]; + state->blocks[3] = *key; + state->blocks[4] = *key; + + crypto_aegis_block_xor(&state->blocks[3], &crypto_aegis_const[0]); + crypto_aegis_block_xor(&state->blocks[4], &crypto_aegis_const[1]); + + for (i = 0; i < 5; i++) { + crypto_aegis128_update_a(state, key, false); + crypto_aegis128_update_a(state, &key_iv, false); + } +} + +static void crypto_aegis128_ad(struct aegis_state *state, + const u8 *src, unsigned int size, + bool do_simd) +{ + if (AEGIS_ALIGNED(src)) { + const union aegis_block *src_blk = + (const union aegis_block *)src; + + while (size >= AEGIS_BLOCK_SIZE) { + crypto_aegis128_update_a(state, src_blk, do_simd); + + size -= AEGIS_BLOCK_SIZE; + src_blk++; + } + } else { + while (size >= AEGIS_BLOCK_SIZE) { + crypto_aegis128_update_u(state, src, do_simd); + + size -= AEGIS_BLOCK_SIZE; + src += AEGIS_BLOCK_SIZE; + } + } +} + +static void crypto_aegis128_wipe_chunk(struct aegis_state *state, u8 *dst, + const u8 *src, unsigned int size) +{ + memzero_explicit(dst, size); +} + +static void crypto_aegis128_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[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_aegis_block_xor(&tmp, src_blk); + + crypto_aegis128_update_a(state, src_blk, false); + + *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[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_xor(tmp.bytes, src, AEGIS_BLOCK_SIZE); + + crypto_aegis128_update_u(state, src, false); + + 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[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + + crypto_aegis128_update_a(state, &msg, false); + + crypto_aegis_block_xor(&msg, &tmp); + + memcpy(dst, msg.bytes, size); + } +} + +static void crypto_aegis128_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[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_aegis_block_xor(&tmp, src_blk); + + crypto_aegis128_update_a(state, &tmp, false); + + *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[4]); + crypto_aegis_block_xor(&tmp, &state->blocks[1]); + crypto_xor(tmp.bytes, src, AEGIS_BLOCK_SIZE); + + crypto_aegis128_update_a(state, &tmp, false); + + 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[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_aegis128_update_a(state, &msg, false); + + memcpy(dst, msg.bytes, size); + } +} + +static void crypto_aegis128_process_ad(struct aegis_state *state, + struct scatterlist *sg_src, + unsigned int assoclen, + bool do_simd) +{ + 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_aegis128_update_a(state, &buf, do_simd); + pos = 0; + left -= fill; + src += fill; + } + + crypto_aegis128_ad(state, src, left, do_simd); + 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_aegis128_update_a(state, &buf, do_simd); + } +} + +static __always_inline +int crypto_aegis128_process_crypt(struct aegis_state *state, + struct skcipher_walk *walk, + void (*crypt)(struct aegis_state *state, + u8 *dst, const u8 *src, + unsigned int size)) +{ + int err = 0; + + while (walk->nbytes) { + unsigned int nbytes = walk->nbytes; + + if (nbytes < walk->total) + nbytes = round_down(nbytes, walk->stride); + + crypt(state, walk->dst.virt.addr, walk->src.virt.addr, nbytes); + + err = skcipher_walk_done(walk, walk->nbytes - nbytes); + } + return err; +} + +static void crypto_aegis128_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_aegis128_update_a(state, &tmp, false); + + for (i = 0; i < AEGIS128_STATE_BLOCKS; i++) + crypto_aegis_block_xor(tag_xor, &state->blocks[i]); +} + +static int crypto_aegis128_setkey(struct crypto_aead *aead, const u8 *key, + unsigned int keylen) +{ + struct aegis_ctx *ctx = crypto_aead_ctx(aead); + + if (keylen != AEGIS128_KEY_SIZE) + return -EINVAL; + + memcpy(ctx->key.bytes, key, AEGIS128_KEY_SIZE); + return 0; +} + +static int crypto_aegis128_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 int crypto_aegis128_encrypt_generic(struct aead_request *req) +{ + struct crypto_aead *tfm = crypto_aead_reqtfm(req); + union aegis_block tag = {}; + unsigned int authsize = crypto_aead_authsize(tfm); + struct aegis_ctx *ctx = crypto_aead_ctx(tfm); + unsigned int cryptlen = req->cryptlen; + struct skcipher_walk walk; + struct aegis_state state; + + skcipher_walk_aead_encrypt(&walk, req, false); + crypto_aegis128_init(&state, &ctx->key, req->iv); + crypto_aegis128_process_ad(&state, req->src, req->assoclen, false); + crypto_aegis128_process_crypt(&state, &walk, + crypto_aegis128_encrypt_chunk); + crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen); + + scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen, + authsize, 1); + return 0; +} + +static int crypto_aegis128_decrypt_generic(struct aead_request *req) +{ + static const u8 zeros[AEGIS128_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; + struct aegis_ctx *ctx = crypto_aead_ctx(tfm); + struct skcipher_walk walk; + struct aegis_state state; + + scatterwalk_map_and_copy(tag.bytes, req->src, req->assoclen + cryptlen, + authsize, 0); + + skcipher_walk_aead_decrypt(&walk, req, false); + crypto_aegis128_init(&state, &ctx->key, req->iv); + crypto_aegis128_process_ad(&state, req->src, req->assoclen, false); + crypto_aegis128_process_crypt(&state, &walk, + crypto_aegis128_decrypt_chunk); + crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen); + + if (unlikely(crypto_memneq(tag.bytes, zeros, authsize))) { + /* + * From Chapter 4. 'Security Analysis' of the AEGIS spec [0] + * + * "3. If verification fails, the decrypted plaintext and the + * wrong authentication tag should not be given as output." + * + * [0] https://competitions.cr.yp.to/round3/aegisv11.pdf + */ + skcipher_walk_aead_decrypt(&walk, req, false); + crypto_aegis128_process_crypt(NULL, &walk, + crypto_aegis128_wipe_chunk); + memzero_explicit(&tag, sizeof(tag)); + return -EBADMSG; + } + return 0; +} + +static int crypto_aegis128_encrypt_simd(struct aead_request *req) +{ + struct crypto_aead *tfm = crypto_aead_reqtfm(req); + union aegis_block tag = {}; + unsigned int authsize = crypto_aead_authsize(tfm); + struct aegis_ctx *ctx = crypto_aead_ctx(tfm); + unsigned int cryptlen = req->cryptlen; + struct skcipher_walk walk; + struct aegis_state state; + + if (!aegis128_do_simd()) + return crypto_aegis128_encrypt_generic(req); + + skcipher_walk_aead_encrypt(&walk, req, false); + crypto_aegis128_init_simd(&state, &ctx->key, req->iv); + crypto_aegis128_process_ad(&state, req->src, req->assoclen, true); + crypto_aegis128_process_crypt(&state, &walk, + crypto_aegis128_encrypt_chunk_simd); + crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen, 0); + + scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen, + authsize, 1); + return 0; +} + +static int crypto_aegis128_decrypt_simd(struct aead_request *req) +{ + 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; + struct aegis_ctx *ctx = crypto_aead_ctx(tfm); + struct skcipher_walk walk; + struct aegis_state state; + + if (!aegis128_do_simd()) + return crypto_aegis128_decrypt_generic(req); + + scatterwalk_map_and_copy(tag.bytes, req->src, req->assoclen + cryptlen, + authsize, 0); + + skcipher_walk_aead_decrypt(&walk, req, false); + crypto_aegis128_init_simd(&state, &ctx->key, req->iv); + crypto_aegis128_process_ad(&state, req->src, req->assoclen, true); + crypto_aegis128_process_crypt(&state, &walk, + crypto_aegis128_decrypt_chunk_simd); + + if (unlikely(crypto_aegis128_final_simd(&state, &tag, req->assoclen, + cryptlen, authsize))) { + skcipher_walk_aead_decrypt(&walk, req, false); + crypto_aegis128_process_crypt(NULL, &walk, + crypto_aegis128_wipe_chunk); + return -EBADMSG; + } + return 0; +} + +static struct aead_alg crypto_aegis128_alg_generic = { + .setkey = crypto_aegis128_setkey, + .setauthsize = crypto_aegis128_setauthsize, + .encrypt = crypto_aegis128_encrypt_generic, + .decrypt = crypto_aegis128_decrypt_generic, + + .ivsize = AEGIS128_NONCE_SIZE, + .maxauthsize = AEGIS128_MAX_AUTH_SIZE, + .chunksize = AEGIS_BLOCK_SIZE, + + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct aegis_ctx), + .base.cra_alignmask = 0, + .base.cra_priority = 100, + .base.cra_name = "aegis128", + .base.cra_driver_name = "aegis128-generic", + .base.cra_module = THIS_MODULE, +}; + +static struct aead_alg crypto_aegis128_alg_simd = { + .setkey = crypto_aegis128_setkey, + .setauthsize = crypto_aegis128_setauthsize, + .encrypt = crypto_aegis128_encrypt_simd, + .decrypt = crypto_aegis128_decrypt_simd, + + .ivsize = AEGIS128_NONCE_SIZE, + .maxauthsize = AEGIS128_MAX_AUTH_SIZE, + .chunksize = AEGIS_BLOCK_SIZE, + + .base.cra_blocksize = 1, + .base.cra_ctxsize = sizeof(struct aegis_ctx), + .base.cra_alignmask = 0, + .base.cra_priority = 200, + .base.cra_name = "aegis128", + .base.cra_driver_name = "aegis128-simd", + .base.cra_module = THIS_MODULE, +}; + +static int __init crypto_aegis128_module_init(void) +{ + int ret; + + ret = crypto_register_aead(&crypto_aegis128_alg_generic); + if (ret) + return ret; + + if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) && + crypto_aegis128_have_simd()) { + ret = crypto_register_aead(&crypto_aegis128_alg_simd); + if (ret) { + crypto_unregister_aead(&crypto_aegis128_alg_generic); + return ret; + } + static_branch_enable(&have_simd); + } + return 0; +} + +static void __exit crypto_aegis128_module_exit(void) +{ + if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) && + crypto_aegis128_have_simd()) + crypto_unregister_aead(&crypto_aegis128_alg_simd); + + crypto_unregister_aead(&crypto_aegis128_alg_generic); +} + +subsys_initcall(crypto_aegis128_module_init); +module_exit(crypto_aegis128_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>"); +MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm"); +MODULE_ALIAS_CRYPTO("aegis128"); +MODULE_ALIAS_CRYPTO("aegis128-generic"); +MODULE_ALIAS_CRYPTO("aegis128-simd"); |