1 /* 2 * The AEGIS-128 Authenticated-Encryption Algorithm 3 * Glue for AES-NI + SSE2 implementation 4 * 5 * Copyright (c) 2017-2018 Ondrej Mosnacek <omosnacek@gmail.com> 6 * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved. 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the Free 10 * Software Foundation; either version 2 of the License, or (at your option) 11 * any later version. 12 */ 13 14 #include <crypto/internal/aead.h> 15 #include <crypto/internal/simd.h> 16 #include <crypto/internal/skcipher.h> 17 #include <crypto/scatterwalk.h> 18 #include <linux/module.h> 19 #include <asm/fpu/api.h> 20 #include <asm/cpu_device_id.h> 21 22 #define AEGIS128_BLOCK_ALIGN 16 23 #define AEGIS128_BLOCK_SIZE 16 24 #define AEGIS128_NONCE_SIZE 16 25 #define AEGIS128_STATE_BLOCKS 5 26 #define AEGIS128_KEY_SIZE 16 27 #define AEGIS128_MIN_AUTH_SIZE 8 28 #define AEGIS128_MAX_AUTH_SIZE 16 29 30 asmlinkage void crypto_aegis128_aesni_init(void *state, void *key, void *iv); 31 32 asmlinkage void crypto_aegis128_aesni_ad( 33 void *state, unsigned int length, const void *data); 34 35 asmlinkage void crypto_aegis128_aesni_enc( 36 void *state, unsigned int length, const void *src, void *dst); 37 38 asmlinkage void crypto_aegis128_aesni_dec( 39 void *state, unsigned int length, const void *src, void *dst); 40 41 asmlinkage void crypto_aegis128_aesni_enc_tail( 42 void *state, unsigned int length, const void *src, void *dst); 43 44 asmlinkage void crypto_aegis128_aesni_dec_tail( 45 void *state, unsigned int length, const void *src, void *dst); 46 47 asmlinkage void crypto_aegis128_aesni_final( 48 void *state, void *tag_xor, unsigned int cryptlen, 49 unsigned int assoclen); 50 51 struct aegis_block { 52 u8 bytes[AEGIS128_BLOCK_SIZE] __aligned(AEGIS128_BLOCK_ALIGN); 53 }; 54 55 struct aegis_state { 56 struct aegis_block blocks[AEGIS128_STATE_BLOCKS]; 57 }; 58 59 struct aegis_ctx { 60 struct aegis_block key; 61 }; 62 63 struct aegis_crypt_ops { 64 int (*skcipher_walk_init)(struct skcipher_walk *walk, 65 struct aead_request *req, bool atomic); 66 67 void (*crypt_blocks)(void *state, unsigned int length, const void *src, 68 void *dst); 69 void (*crypt_tail)(void *state, unsigned int length, const void *src, 70 void *dst); 71 }; 72 73 static void crypto_aegis128_aesni_process_ad( 74 struct aegis_state *state, struct scatterlist *sg_src, 75 unsigned int assoclen) 76 { 77 struct scatter_walk walk; 78 struct aegis_block buf; 79 unsigned int pos = 0; 80 81 scatterwalk_start(&walk, sg_src); 82 while (assoclen != 0) { 83 unsigned int size = scatterwalk_clamp(&walk, assoclen); 84 unsigned int left = size; 85 void *mapped = scatterwalk_map(&walk); 86 const u8 *src = (const u8 *)mapped; 87 88 if (pos + size >= AEGIS128_BLOCK_SIZE) { 89 if (pos > 0) { 90 unsigned int fill = AEGIS128_BLOCK_SIZE - pos; 91 memcpy(buf.bytes + pos, src, fill); 92 crypto_aegis128_aesni_ad(state, 93 AEGIS128_BLOCK_SIZE, 94 buf.bytes); 95 pos = 0; 96 left -= fill; 97 src += fill; 98 } 99 100 crypto_aegis128_aesni_ad(state, left, src); 101 102 src += left & ~(AEGIS128_BLOCK_SIZE - 1); 103 left &= AEGIS128_BLOCK_SIZE - 1; 104 } 105 106 memcpy(buf.bytes + pos, src, left); 107 pos += left; 108 assoclen -= size; 109 110 scatterwalk_unmap(mapped); 111 scatterwalk_advance(&walk, size); 112 scatterwalk_done(&walk, 0, assoclen); 113 } 114 115 if (pos > 0) { 116 memset(buf.bytes + pos, 0, AEGIS128_BLOCK_SIZE - pos); 117 crypto_aegis128_aesni_ad(state, AEGIS128_BLOCK_SIZE, buf.bytes); 118 } 119 } 120 121 static void crypto_aegis128_aesni_process_crypt( 122 struct aegis_state *state, struct skcipher_walk *walk, 123 const struct aegis_crypt_ops *ops) 124 { 125 while (walk->nbytes >= AEGIS128_BLOCK_SIZE) { 126 ops->crypt_blocks(state, 127 round_down(walk->nbytes, AEGIS128_BLOCK_SIZE), 128 walk->src.virt.addr, walk->dst.virt.addr); 129 skcipher_walk_done(walk, walk->nbytes % AEGIS128_BLOCK_SIZE); 130 } 131 132 if (walk->nbytes) { 133 ops->crypt_tail(state, walk->nbytes, walk->src.virt.addr, 134 walk->dst.virt.addr); 135 skcipher_walk_done(walk, 0); 136 } 137 } 138 139 static struct aegis_ctx *crypto_aegis128_aesni_ctx(struct crypto_aead *aead) 140 { 141 u8 *ctx = crypto_aead_ctx(aead); 142 ctx = PTR_ALIGN(ctx, __alignof__(struct aegis_ctx)); 143 return (void *)ctx; 144 } 145 146 static int crypto_aegis128_aesni_setkey(struct crypto_aead *aead, const u8 *key, 147 unsigned int keylen) 148 { 149 struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(aead); 150 151 if (keylen != AEGIS128_KEY_SIZE) { 152 crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN); 153 return -EINVAL; 154 } 155 156 memcpy(ctx->key.bytes, key, AEGIS128_KEY_SIZE); 157 158 return 0; 159 } 160 161 static int crypto_aegis128_aesni_setauthsize(struct crypto_aead *tfm, 162 unsigned int authsize) 163 { 164 if (authsize > AEGIS128_MAX_AUTH_SIZE) 165 return -EINVAL; 166 if (authsize < AEGIS128_MIN_AUTH_SIZE) 167 return -EINVAL; 168 return 0; 169 } 170 171 static void crypto_aegis128_aesni_crypt(struct aead_request *req, 172 struct aegis_block *tag_xor, 173 unsigned int cryptlen, 174 const struct aegis_crypt_ops *ops) 175 { 176 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 177 struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(tfm); 178 struct skcipher_walk walk; 179 struct aegis_state state; 180 181 ops->skcipher_walk_init(&walk, req, true); 182 183 kernel_fpu_begin(); 184 185 crypto_aegis128_aesni_init(&state, ctx->key.bytes, req->iv); 186 crypto_aegis128_aesni_process_ad(&state, req->src, req->assoclen); 187 crypto_aegis128_aesni_process_crypt(&state, &walk, ops); 188 crypto_aegis128_aesni_final(&state, tag_xor, req->assoclen, cryptlen); 189 190 kernel_fpu_end(); 191 } 192 193 static int crypto_aegis128_aesni_encrypt(struct aead_request *req) 194 { 195 static const struct aegis_crypt_ops OPS = { 196 .skcipher_walk_init = skcipher_walk_aead_encrypt, 197 .crypt_blocks = crypto_aegis128_aesni_enc, 198 .crypt_tail = crypto_aegis128_aesni_enc_tail, 199 }; 200 201 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 202 struct aegis_block tag = {}; 203 unsigned int authsize = crypto_aead_authsize(tfm); 204 unsigned int cryptlen = req->cryptlen; 205 206 crypto_aegis128_aesni_crypt(req, &tag, cryptlen, &OPS); 207 208 scatterwalk_map_and_copy(tag.bytes, req->dst, 209 req->assoclen + cryptlen, authsize, 1); 210 return 0; 211 } 212 213 static int crypto_aegis128_aesni_decrypt(struct aead_request *req) 214 { 215 static const struct aegis_block zeros = {}; 216 217 static const struct aegis_crypt_ops OPS = { 218 .skcipher_walk_init = skcipher_walk_aead_decrypt, 219 .crypt_blocks = crypto_aegis128_aesni_dec, 220 .crypt_tail = crypto_aegis128_aesni_dec_tail, 221 }; 222 223 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 224 struct aegis_block tag; 225 unsigned int authsize = crypto_aead_authsize(tfm); 226 unsigned int cryptlen = req->cryptlen - authsize; 227 228 scatterwalk_map_and_copy(tag.bytes, req->src, 229 req->assoclen + cryptlen, authsize, 0); 230 231 crypto_aegis128_aesni_crypt(req, &tag, cryptlen, &OPS); 232 233 return crypto_memneq(tag.bytes, zeros.bytes, authsize) ? -EBADMSG : 0; 234 } 235 236 static int crypto_aegis128_aesni_init_tfm(struct crypto_aead *aead) 237 { 238 return 0; 239 } 240 241 static void crypto_aegis128_aesni_exit_tfm(struct crypto_aead *aead) 242 { 243 } 244 245 static struct aead_alg crypto_aegis128_aesni_alg = { 246 .setkey = crypto_aegis128_aesni_setkey, 247 .setauthsize = crypto_aegis128_aesni_setauthsize, 248 .encrypt = crypto_aegis128_aesni_encrypt, 249 .decrypt = crypto_aegis128_aesni_decrypt, 250 .init = crypto_aegis128_aesni_init_tfm, 251 .exit = crypto_aegis128_aesni_exit_tfm, 252 253 .ivsize = AEGIS128_NONCE_SIZE, 254 .maxauthsize = AEGIS128_MAX_AUTH_SIZE, 255 .chunksize = AEGIS128_BLOCK_SIZE, 256 257 .base = { 258 .cra_flags = CRYPTO_ALG_INTERNAL, 259 .cra_blocksize = 1, 260 .cra_ctxsize = sizeof(struct aegis_ctx) + 261 __alignof__(struct aegis_ctx), 262 .cra_alignmask = 0, 263 .cra_priority = 400, 264 265 .cra_name = "__aegis128", 266 .cra_driver_name = "__aegis128-aesni", 267 268 .cra_module = THIS_MODULE, 269 } 270 }; 271 272 static struct simd_aead_alg *simd_alg; 273 274 static int __init crypto_aegis128_aesni_module_init(void) 275 { 276 if (!boot_cpu_has(X86_FEATURE_XMM2) || 277 !boot_cpu_has(X86_FEATURE_AES) || 278 !cpu_has_xfeatures(XFEATURE_MASK_SSE, NULL)) 279 return -ENODEV; 280 281 return simd_register_aeads_compat(&crypto_aegis128_aesni_alg, 1, 282 &simd_alg); 283 } 284 285 static void __exit crypto_aegis128_aesni_module_exit(void) 286 { 287 simd_unregister_aeads(&crypto_aegis128_aesni_alg, 1, &simd_alg); 288 } 289 290 module_init(crypto_aegis128_aesni_module_init); 291 module_exit(crypto_aegis128_aesni_module_exit); 292 293 MODULE_LICENSE("GPL"); 294 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>"); 295 MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm -- AESNI+SSE2 implementation"); 296 MODULE_ALIAS_CRYPTO("aegis128"); 297 MODULE_ALIAS_CRYPTO("aegis128-aesni"); 298