1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * The AEGIS-128 Authenticated-Encryption Algorithm 4 * Glue for AES-NI + SSE2 implementation 5 * 6 * Copyright (c) 2017-2018 Ondrej Mosnacek <omosnacek@gmail.com> 7 * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved. 8 */ 9 10 #include <crypto/internal/aead.h> 11 #include <crypto/internal/simd.h> 12 #include <crypto/internal/skcipher.h> 13 #include <crypto/scatterwalk.h> 14 #include <linux/module.h> 15 #include <asm/fpu/api.h> 16 #include <asm/cpu_device_id.h> 17 18 #define AEGIS128_BLOCK_ALIGN 16 19 #define AEGIS128_BLOCK_SIZE 16 20 #define AEGIS128_NONCE_SIZE 16 21 #define AEGIS128_STATE_BLOCKS 5 22 #define AEGIS128_KEY_SIZE 16 23 #define AEGIS128_MIN_AUTH_SIZE 8 24 #define AEGIS128_MAX_AUTH_SIZE 16 25 26 asmlinkage void crypto_aegis128_aesni_init(void *state, void *key, void *iv); 27 28 asmlinkage void crypto_aegis128_aesni_ad( 29 void *state, unsigned int length, const void *data); 30 31 asmlinkage void crypto_aegis128_aesni_enc( 32 void *state, unsigned int length, const void *src, void *dst); 33 34 asmlinkage void crypto_aegis128_aesni_dec( 35 void *state, unsigned int length, const void *src, void *dst); 36 37 asmlinkage void crypto_aegis128_aesni_enc_tail( 38 void *state, unsigned int length, const void *src, void *dst); 39 40 asmlinkage void crypto_aegis128_aesni_dec_tail( 41 void *state, unsigned int length, const void *src, void *dst); 42 43 asmlinkage void crypto_aegis128_aesni_final( 44 void *state, void *tag_xor, unsigned int cryptlen, 45 unsigned int assoclen); 46 47 struct aegis_block { 48 u8 bytes[AEGIS128_BLOCK_SIZE] __aligned(AEGIS128_BLOCK_ALIGN); 49 }; 50 51 struct aegis_state { 52 struct aegis_block blocks[AEGIS128_STATE_BLOCKS]; 53 }; 54 55 struct aegis_ctx { 56 struct aegis_block key; 57 }; 58 59 struct aegis_crypt_ops { 60 int (*skcipher_walk_init)(struct skcipher_walk *walk, 61 struct aead_request *req, bool atomic); 62 63 void (*crypt_blocks)(void *state, unsigned int length, const void *src, 64 void *dst); 65 void (*crypt_tail)(void *state, unsigned int length, const void *src, 66 void *dst); 67 }; 68 69 static void crypto_aegis128_aesni_process_ad( 70 struct aegis_state *state, struct scatterlist *sg_src, 71 unsigned int assoclen) 72 { 73 struct scatter_walk walk; 74 struct aegis_block buf; 75 unsigned int pos = 0; 76 77 scatterwalk_start(&walk, sg_src); 78 while (assoclen != 0) { 79 unsigned int size = scatterwalk_clamp(&walk, assoclen); 80 unsigned int left = size; 81 void *mapped = scatterwalk_map(&walk); 82 const u8 *src = (const u8 *)mapped; 83 84 if (pos + size >= AEGIS128_BLOCK_SIZE) { 85 if (pos > 0) { 86 unsigned int fill = AEGIS128_BLOCK_SIZE - pos; 87 memcpy(buf.bytes + pos, src, fill); 88 crypto_aegis128_aesni_ad(state, 89 AEGIS128_BLOCK_SIZE, 90 buf.bytes); 91 pos = 0; 92 left -= fill; 93 src += fill; 94 } 95 96 crypto_aegis128_aesni_ad(state, left, src); 97 98 src += left & ~(AEGIS128_BLOCK_SIZE - 1); 99 left &= AEGIS128_BLOCK_SIZE - 1; 100 } 101 102 memcpy(buf.bytes + pos, src, left); 103 pos += left; 104 assoclen -= size; 105 106 scatterwalk_unmap(mapped); 107 scatterwalk_advance(&walk, size); 108 scatterwalk_done(&walk, 0, assoclen); 109 } 110 111 if (pos > 0) { 112 memset(buf.bytes + pos, 0, AEGIS128_BLOCK_SIZE - pos); 113 crypto_aegis128_aesni_ad(state, AEGIS128_BLOCK_SIZE, buf.bytes); 114 } 115 } 116 117 static void crypto_aegis128_aesni_process_crypt( 118 struct aegis_state *state, struct skcipher_walk *walk, 119 const struct aegis_crypt_ops *ops) 120 { 121 while (walk->nbytes >= AEGIS128_BLOCK_SIZE) { 122 ops->crypt_blocks(state, 123 round_down(walk->nbytes, AEGIS128_BLOCK_SIZE), 124 walk->src.virt.addr, walk->dst.virt.addr); 125 skcipher_walk_done(walk, walk->nbytes % AEGIS128_BLOCK_SIZE); 126 } 127 128 if (walk->nbytes) { 129 ops->crypt_tail(state, walk->nbytes, walk->src.virt.addr, 130 walk->dst.virt.addr); 131 skcipher_walk_done(walk, 0); 132 } 133 } 134 135 static struct aegis_ctx *crypto_aegis128_aesni_ctx(struct crypto_aead *aead) 136 { 137 u8 *ctx = crypto_aead_ctx(aead); 138 ctx = PTR_ALIGN(ctx, __alignof__(struct aegis_ctx)); 139 return (void *)ctx; 140 } 141 142 static int crypto_aegis128_aesni_setkey(struct crypto_aead *aead, const u8 *key, 143 unsigned int keylen) 144 { 145 struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(aead); 146 147 if (keylen != AEGIS128_KEY_SIZE) 148 return -EINVAL; 149 150 memcpy(ctx->key.bytes, key, AEGIS128_KEY_SIZE); 151 152 return 0; 153 } 154 155 static int crypto_aegis128_aesni_setauthsize(struct crypto_aead *tfm, 156 unsigned int authsize) 157 { 158 if (authsize > AEGIS128_MAX_AUTH_SIZE) 159 return -EINVAL; 160 if (authsize < AEGIS128_MIN_AUTH_SIZE) 161 return -EINVAL; 162 return 0; 163 } 164 165 static void crypto_aegis128_aesni_crypt(struct aead_request *req, 166 struct aegis_block *tag_xor, 167 unsigned int cryptlen, 168 const struct aegis_crypt_ops *ops) 169 { 170 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 171 struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(tfm); 172 struct skcipher_walk walk; 173 struct aegis_state state; 174 175 ops->skcipher_walk_init(&walk, req, true); 176 177 kernel_fpu_begin(); 178 179 crypto_aegis128_aesni_init(&state, ctx->key.bytes, req->iv); 180 crypto_aegis128_aesni_process_ad(&state, req->src, req->assoclen); 181 crypto_aegis128_aesni_process_crypt(&state, &walk, ops); 182 crypto_aegis128_aesni_final(&state, tag_xor, req->assoclen, cryptlen); 183 184 kernel_fpu_end(); 185 } 186 187 static int crypto_aegis128_aesni_encrypt(struct aead_request *req) 188 { 189 static const struct aegis_crypt_ops OPS = { 190 .skcipher_walk_init = skcipher_walk_aead_encrypt, 191 .crypt_blocks = crypto_aegis128_aesni_enc, 192 .crypt_tail = crypto_aegis128_aesni_enc_tail, 193 }; 194 195 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 196 struct aegis_block tag = {}; 197 unsigned int authsize = crypto_aead_authsize(tfm); 198 unsigned int cryptlen = req->cryptlen; 199 200 crypto_aegis128_aesni_crypt(req, &tag, cryptlen, &OPS); 201 202 scatterwalk_map_and_copy(tag.bytes, req->dst, 203 req->assoclen + cryptlen, authsize, 1); 204 return 0; 205 } 206 207 static int crypto_aegis128_aesni_decrypt(struct aead_request *req) 208 { 209 static const struct aegis_block zeros = {}; 210 211 static const struct aegis_crypt_ops OPS = { 212 .skcipher_walk_init = skcipher_walk_aead_decrypt, 213 .crypt_blocks = crypto_aegis128_aesni_dec, 214 .crypt_tail = crypto_aegis128_aesni_dec_tail, 215 }; 216 217 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 218 struct aegis_block tag; 219 unsigned int authsize = crypto_aead_authsize(tfm); 220 unsigned int cryptlen = req->cryptlen - authsize; 221 222 scatterwalk_map_and_copy(tag.bytes, req->src, 223 req->assoclen + cryptlen, authsize, 0); 224 225 crypto_aegis128_aesni_crypt(req, &tag, cryptlen, &OPS); 226 227 return crypto_memneq(tag.bytes, zeros.bytes, authsize) ? -EBADMSG : 0; 228 } 229 230 static int crypto_aegis128_aesni_init_tfm(struct crypto_aead *aead) 231 { 232 return 0; 233 } 234 235 static void crypto_aegis128_aesni_exit_tfm(struct crypto_aead *aead) 236 { 237 } 238 239 static struct aead_alg crypto_aegis128_aesni_alg = { 240 .setkey = crypto_aegis128_aesni_setkey, 241 .setauthsize = crypto_aegis128_aesni_setauthsize, 242 .encrypt = crypto_aegis128_aesni_encrypt, 243 .decrypt = crypto_aegis128_aesni_decrypt, 244 .init = crypto_aegis128_aesni_init_tfm, 245 .exit = crypto_aegis128_aesni_exit_tfm, 246 247 .ivsize = AEGIS128_NONCE_SIZE, 248 .maxauthsize = AEGIS128_MAX_AUTH_SIZE, 249 .chunksize = AEGIS128_BLOCK_SIZE, 250 251 .base = { 252 .cra_flags = CRYPTO_ALG_INTERNAL, 253 .cra_blocksize = 1, 254 .cra_ctxsize = sizeof(struct aegis_ctx) + 255 __alignof__(struct aegis_ctx), 256 .cra_alignmask = 0, 257 .cra_priority = 400, 258 259 .cra_name = "__aegis128", 260 .cra_driver_name = "__aegis128-aesni", 261 262 .cra_module = THIS_MODULE, 263 } 264 }; 265 266 static struct simd_aead_alg *simd_alg; 267 268 static int __init crypto_aegis128_aesni_module_init(void) 269 { 270 if (!boot_cpu_has(X86_FEATURE_XMM2) || 271 !boot_cpu_has(X86_FEATURE_AES) || 272 !cpu_has_xfeatures(XFEATURE_MASK_SSE, NULL)) 273 return -ENODEV; 274 275 return simd_register_aeads_compat(&crypto_aegis128_aesni_alg, 1, 276 &simd_alg); 277 } 278 279 static void __exit crypto_aegis128_aesni_module_exit(void) 280 { 281 simd_unregister_aeads(&crypto_aegis128_aesni_alg, 1, &simd_alg); 282 } 283 284 module_init(crypto_aegis128_aesni_module_init); 285 module_exit(crypto_aegis128_aesni_module_exit); 286 287 MODULE_LICENSE("GPL"); 288 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>"); 289 MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm -- AESNI+SSE2 implementation"); 290 MODULE_ALIAS_CRYPTO("aegis128"); 291 MODULE_ALIAS_CRYPTO("aegis128-aesni"); 292