1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * The AEGIS-128 Authenticated-Encryption Algorithm 4 * Glue for AES-NI + SSE4.1 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/skcipher.h> 12 #include <crypto/scatterwalk.h> 13 #include <linux/module.h> 14 #include <asm/fpu/api.h> 15 #include <asm/cpu_device_id.h> 16 17 #define AEGIS128_BLOCK_ALIGN 16 18 #define AEGIS128_BLOCK_SIZE 16 19 #define AEGIS128_NONCE_SIZE 16 20 #define AEGIS128_STATE_BLOCKS 5 21 #define AEGIS128_KEY_SIZE 16 22 #define AEGIS128_MIN_AUTH_SIZE 8 23 #define AEGIS128_MAX_AUTH_SIZE 16 24 25 struct aegis_block { 26 u8 bytes[AEGIS128_BLOCK_SIZE] __aligned(AEGIS128_BLOCK_ALIGN); 27 }; 28 29 struct aegis_state { 30 struct aegis_block blocks[AEGIS128_STATE_BLOCKS]; 31 }; 32 33 struct aegis_ctx { 34 struct aegis_block key; 35 }; 36 37 asmlinkage void aegis128_aesni_init(struct aegis_state *state, 38 const struct aegis_block *key, 39 const u8 iv[AEGIS128_NONCE_SIZE]); 40 41 asmlinkage void aegis128_aesni_ad(struct aegis_state *state, const u8 *data, 42 unsigned int len); 43 44 asmlinkage void aegis128_aesni_enc(struct aegis_state *state, const u8 *src, 45 u8 *dst, unsigned int len); 46 47 asmlinkage void aegis128_aesni_dec(struct aegis_state *state, const u8 *src, 48 u8 *dst, unsigned int len); 49 50 asmlinkage void aegis128_aesni_enc_tail(struct aegis_state *state, 51 const u8 *src, u8 *dst, 52 unsigned int len); 53 54 asmlinkage void aegis128_aesni_dec_tail(struct aegis_state *state, 55 const u8 *src, u8 *dst, 56 unsigned int len); 57 58 asmlinkage void aegis128_aesni_final(struct aegis_state *state, 59 struct aegis_block *tag_xor, 60 unsigned int assoclen, 61 unsigned int cryptlen); 62 63 static void crypto_aegis128_aesni_process_ad( 64 struct aegis_state *state, struct scatterlist *sg_src, 65 unsigned int assoclen) 66 { 67 struct scatter_walk walk; 68 struct aegis_block buf; 69 unsigned int pos = 0; 70 71 scatterwalk_start(&walk, sg_src); 72 while (assoclen != 0) { 73 unsigned int size = scatterwalk_next(&walk, assoclen); 74 const u8 *src = walk.addr; 75 unsigned int left = size; 76 77 if (pos + size >= AEGIS128_BLOCK_SIZE) { 78 if (pos > 0) { 79 unsigned int fill = AEGIS128_BLOCK_SIZE - pos; 80 memcpy(buf.bytes + pos, src, fill); 81 aegis128_aesni_ad(state, buf.bytes, 82 AEGIS128_BLOCK_SIZE); 83 pos = 0; 84 left -= fill; 85 src += fill; 86 } 87 88 aegis128_aesni_ad(state, src, 89 left & ~(AEGIS128_BLOCK_SIZE - 1)); 90 src += left & ~(AEGIS128_BLOCK_SIZE - 1); 91 left &= AEGIS128_BLOCK_SIZE - 1; 92 } 93 94 memcpy(buf.bytes + pos, src, left); 95 pos += left; 96 assoclen -= size; 97 98 scatterwalk_done_src(&walk, size); 99 } 100 101 if (pos > 0) { 102 memset(buf.bytes + pos, 0, AEGIS128_BLOCK_SIZE - pos); 103 aegis128_aesni_ad(state, buf.bytes, AEGIS128_BLOCK_SIZE); 104 } 105 } 106 107 static __always_inline void 108 crypto_aegis128_aesni_process_crypt(struct aegis_state *state, 109 struct skcipher_walk *walk, bool enc) 110 { 111 while (walk->nbytes >= AEGIS128_BLOCK_SIZE) { 112 if (enc) 113 aegis128_aesni_enc(state, walk->src.virt.addr, 114 walk->dst.virt.addr, 115 round_down(walk->nbytes, 116 AEGIS128_BLOCK_SIZE)); 117 else 118 aegis128_aesni_dec(state, walk->src.virt.addr, 119 walk->dst.virt.addr, 120 round_down(walk->nbytes, 121 AEGIS128_BLOCK_SIZE)); 122 skcipher_walk_done(walk, walk->nbytes % AEGIS128_BLOCK_SIZE); 123 } 124 125 if (walk->nbytes) { 126 if (enc) 127 aegis128_aesni_enc_tail(state, walk->src.virt.addr, 128 walk->dst.virt.addr, 129 walk->nbytes); 130 else 131 aegis128_aesni_dec_tail(state, walk->src.virt.addr, 132 walk->dst.virt.addr, 133 walk->nbytes); 134 skcipher_walk_done(walk, 0); 135 } 136 } 137 138 static struct aegis_ctx *crypto_aegis128_aesni_ctx(struct crypto_aead *aead) 139 { 140 u8 *ctx = crypto_aead_ctx(aead); 141 ctx = PTR_ALIGN(ctx, __alignof__(struct aegis_ctx)); 142 return (void *)ctx; 143 } 144 145 static int crypto_aegis128_aesni_setkey(struct crypto_aead *aead, const u8 *key, 146 unsigned int keylen) 147 { 148 struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(aead); 149 150 if (keylen != AEGIS128_KEY_SIZE) 151 return -EINVAL; 152 153 memcpy(ctx->key.bytes, key, AEGIS128_KEY_SIZE); 154 155 return 0; 156 } 157 158 static int crypto_aegis128_aesni_setauthsize(struct crypto_aead *tfm, 159 unsigned int authsize) 160 { 161 if (authsize > AEGIS128_MAX_AUTH_SIZE) 162 return -EINVAL; 163 if (authsize < AEGIS128_MIN_AUTH_SIZE) 164 return -EINVAL; 165 return 0; 166 } 167 168 static __always_inline void 169 crypto_aegis128_aesni_crypt(struct aead_request *req, 170 struct aegis_block *tag_xor, 171 unsigned int cryptlen, bool enc) 172 { 173 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 174 struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(tfm); 175 struct skcipher_walk walk; 176 struct aegis_state state; 177 178 if (enc) 179 skcipher_walk_aead_encrypt(&walk, req, true); 180 else 181 skcipher_walk_aead_decrypt(&walk, req, true); 182 183 kernel_fpu_begin(); 184 185 aegis128_aesni_init(&state, &ctx->key, req->iv); 186 crypto_aegis128_aesni_process_ad(&state, req->src, req->assoclen); 187 crypto_aegis128_aesni_process_crypt(&state, &walk, enc); 188 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 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, true); 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 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 212 struct aegis_block tag; 213 unsigned int authsize = crypto_aead_authsize(tfm); 214 unsigned int cryptlen = req->cryptlen - authsize; 215 216 scatterwalk_map_and_copy(tag.bytes, req->src, 217 req->assoclen + cryptlen, authsize, 0); 218 219 crypto_aegis128_aesni_crypt(req, &tag, cryptlen, false); 220 221 return crypto_memneq(tag.bytes, zeros.bytes, authsize) ? -EBADMSG : 0; 222 } 223 224 static struct aead_alg crypto_aegis128_aesni_alg = { 225 .setkey = crypto_aegis128_aesni_setkey, 226 .setauthsize = crypto_aegis128_aesni_setauthsize, 227 .encrypt = crypto_aegis128_aesni_encrypt, 228 .decrypt = crypto_aegis128_aesni_decrypt, 229 230 .ivsize = AEGIS128_NONCE_SIZE, 231 .maxauthsize = AEGIS128_MAX_AUTH_SIZE, 232 .chunksize = AEGIS128_BLOCK_SIZE, 233 234 .base = { 235 .cra_blocksize = 1, 236 .cra_ctxsize = sizeof(struct aegis_ctx) + 237 __alignof__(struct aegis_ctx), 238 .cra_priority = 400, 239 240 .cra_name = "aegis128", 241 .cra_driver_name = "aegis128-aesni", 242 243 .cra_module = THIS_MODULE, 244 } 245 }; 246 247 static int __init crypto_aegis128_aesni_module_init(void) 248 { 249 if (!boot_cpu_has(X86_FEATURE_XMM4_1) || 250 !boot_cpu_has(X86_FEATURE_AES) || 251 !cpu_has_xfeatures(XFEATURE_MASK_SSE, NULL)) 252 return -ENODEV; 253 254 return crypto_register_aead(&crypto_aegis128_aesni_alg); 255 } 256 257 static void __exit crypto_aegis128_aesni_module_exit(void) 258 { 259 crypto_unregister_aead(&crypto_aegis128_aesni_alg); 260 } 261 262 module_init(crypto_aegis128_aesni_module_init); 263 module_exit(crypto_aegis128_aesni_module_exit); 264 265 MODULE_LICENSE("GPL"); 266 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>"); 267 MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm -- AESNI+SSE4.1 implementation"); 268 MODULE_ALIAS_CRYPTO("aegis128"); 269 MODULE_ALIAS_CRYPTO("aegis128-aesni"); 270