1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AMD Cryptographic Coprocessor (CCP) AES crypto API support 4 * 5 * Copyright (C) 2013-2019 Advanced Micro Devices, Inc. 6 * 7 * Author: Tom Lendacky <thomas.lendacky@amd.com> 8 */ 9 10 #include <linux/module.h> 11 #include <linux/sched.h> 12 #include <linux/delay.h> 13 #include <linux/scatterlist.h> 14 #include <linux/crypto.h> 15 #include <crypto/algapi.h> 16 #include <crypto/aes.h> 17 #include <crypto/ctr.h> 18 #include <crypto/scatterwalk.h> 19 20 #include "ccp-crypto.h" 21 22 static int ccp_aes_complete(struct crypto_async_request *async_req, int ret) 23 { 24 struct skcipher_request *req = skcipher_request_cast(async_req); 25 struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm); 26 struct ccp_aes_req_ctx *rctx = skcipher_request_ctx(req); 27 28 if (ret) 29 return ret; 30 31 if (ctx->u.aes.mode != CCP_AES_MODE_ECB) 32 memcpy(req->iv, rctx->iv, AES_BLOCK_SIZE); 33 34 return 0; 35 } 36 37 static int ccp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key, 38 unsigned int key_len) 39 { 40 struct ccp_crypto_skcipher_alg *alg = ccp_crypto_skcipher_alg(tfm); 41 struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm); 42 43 switch (key_len) { 44 case AES_KEYSIZE_128: 45 ctx->u.aes.type = CCP_AES_TYPE_128; 46 break; 47 case AES_KEYSIZE_192: 48 ctx->u.aes.type = CCP_AES_TYPE_192; 49 break; 50 case AES_KEYSIZE_256: 51 ctx->u.aes.type = CCP_AES_TYPE_256; 52 break; 53 default: 54 return -EINVAL; 55 } 56 ctx->u.aes.mode = alg->mode; 57 ctx->u.aes.key_len = key_len; 58 59 memcpy(ctx->u.aes.key, key, key_len); 60 sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len); 61 62 return 0; 63 } 64 65 static int ccp_aes_crypt(struct skcipher_request *req, bool encrypt) 66 { 67 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 68 struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm); 69 struct ccp_aes_req_ctx *rctx = skcipher_request_ctx(req); 70 struct scatterlist *iv_sg = NULL; 71 unsigned int iv_len = 0; 72 73 if (!ctx->u.aes.key_len) 74 return -EINVAL; 75 76 if (((ctx->u.aes.mode == CCP_AES_MODE_ECB) || 77 (ctx->u.aes.mode == CCP_AES_MODE_CBC)) && 78 (req->cryptlen & (AES_BLOCK_SIZE - 1))) 79 return -EINVAL; 80 81 if (ctx->u.aes.mode != CCP_AES_MODE_ECB) { 82 if (!req->iv) 83 return -EINVAL; 84 85 memcpy(rctx->iv, req->iv, AES_BLOCK_SIZE); 86 iv_sg = &rctx->iv_sg; 87 iv_len = AES_BLOCK_SIZE; 88 sg_init_one(iv_sg, rctx->iv, iv_len); 89 } 90 91 memset(&rctx->cmd, 0, sizeof(rctx->cmd)); 92 INIT_LIST_HEAD(&rctx->cmd.entry); 93 rctx->cmd.engine = CCP_ENGINE_AES; 94 rctx->cmd.u.aes.type = ctx->u.aes.type; 95 rctx->cmd.u.aes.mode = ctx->u.aes.mode; 96 rctx->cmd.u.aes.action = 97 (encrypt) ? CCP_AES_ACTION_ENCRYPT : CCP_AES_ACTION_DECRYPT; 98 rctx->cmd.u.aes.key = &ctx->u.aes.key_sg; 99 rctx->cmd.u.aes.key_len = ctx->u.aes.key_len; 100 rctx->cmd.u.aes.iv = iv_sg; 101 rctx->cmd.u.aes.iv_len = iv_len; 102 rctx->cmd.u.aes.src = req->src; 103 rctx->cmd.u.aes.src_len = req->cryptlen; 104 rctx->cmd.u.aes.dst = req->dst; 105 106 return ccp_crypto_enqueue_request(&req->base, &rctx->cmd); 107 } 108 109 static int ccp_aes_encrypt(struct skcipher_request *req) 110 { 111 return ccp_aes_crypt(req, true); 112 } 113 114 static int ccp_aes_decrypt(struct skcipher_request *req) 115 { 116 return ccp_aes_crypt(req, false); 117 } 118 119 static int ccp_aes_init_tfm(struct crypto_skcipher *tfm) 120 { 121 struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm); 122 123 ctx->complete = ccp_aes_complete; 124 ctx->u.aes.key_len = 0; 125 126 crypto_skcipher_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx)); 127 128 return 0; 129 } 130 131 static int ccp_aes_rfc3686_complete(struct crypto_async_request *async_req, 132 int ret) 133 { 134 struct skcipher_request *req = skcipher_request_cast(async_req); 135 struct ccp_aes_req_ctx *rctx = skcipher_request_ctx(req); 136 137 /* Restore the original pointer */ 138 req->iv = rctx->rfc3686_info; 139 140 return ccp_aes_complete(async_req, ret); 141 } 142 143 static int ccp_aes_rfc3686_setkey(struct crypto_skcipher *tfm, const u8 *key, 144 unsigned int key_len) 145 { 146 struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm); 147 148 if (key_len < CTR_RFC3686_NONCE_SIZE) 149 return -EINVAL; 150 151 key_len -= CTR_RFC3686_NONCE_SIZE; 152 memcpy(ctx->u.aes.nonce, key + key_len, CTR_RFC3686_NONCE_SIZE); 153 154 return ccp_aes_setkey(tfm, key, key_len); 155 } 156 157 static int ccp_aes_rfc3686_crypt(struct skcipher_request *req, bool encrypt) 158 { 159 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 160 struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm); 161 struct ccp_aes_req_ctx *rctx = skcipher_request_ctx(req); 162 u8 *iv; 163 164 /* Initialize the CTR block */ 165 iv = rctx->rfc3686_iv; 166 memcpy(iv, ctx->u.aes.nonce, CTR_RFC3686_NONCE_SIZE); 167 168 iv += CTR_RFC3686_NONCE_SIZE; 169 memcpy(iv, req->iv, CTR_RFC3686_IV_SIZE); 170 171 iv += CTR_RFC3686_IV_SIZE; 172 *(__be32 *)iv = cpu_to_be32(1); 173 174 /* Point to the new IV */ 175 rctx->rfc3686_info = req->iv; 176 req->iv = rctx->rfc3686_iv; 177 178 return ccp_aes_crypt(req, encrypt); 179 } 180 181 static int ccp_aes_rfc3686_encrypt(struct skcipher_request *req) 182 { 183 return ccp_aes_rfc3686_crypt(req, true); 184 } 185 186 static int ccp_aes_rfc3686_decrypt(struct skcipher_request *req) 187 { 188 return ccp_aes_rfc3686_crypt(req, false); 189 } 190 191 static int ccp_aes_rfc3686_init_tfm(struct crypto_skcipher *tfm) 192 { 193 struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm); 194 195 ctx->complete = ccp_aes_rfc3686_complete; 196 ctx->u.aes.key_len = 0; 197 198 crypto_skcipher_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx)); 199 200 return 0; 201 } 202 203 static const struct skcipher_alg ccp_aes_defaults = { 204 .setkey = ccp_aes_setkey, 205 .encrypt = ccp_aes_encrypt, 206 .decrypt = ccp_aes_decrypt, 207 .min_keysize = AES_MIN_KEY_SIZE, 208 .max_keysize = AES_MAX_KEY_SIZE, 209 .init = ccp_aes_init_tfm, 210 211 .base.cra_flags = CRYPTO_ALG_ASYNC | 212 CRYPTO_ALG_ALLOCATES_MEMORY | 213 CRYPTO_ALG_KERN_DRIVER_ONLY | 214 CRYPTO_ALG_NEED_FALLBACK, 215 .base.cra_blocksize = AES_BLOCK_SIZE, 216 .base.cra_ctxsize = sizeof(struct ccp_ctx), 217 .base.cra_priority = CCP_CRA_PRIORITY, 218 .base.cra_module = THIS_MODULE, 219 }; 220 221 static const struct skcipher_alg ccp_aes_rfc3686_defaults = { 222 .setkey = ccp_aes_rfc3686_setkey, 223 .encrypt = ccp_aes_rfc3686_encrypt, 224 .decrypt = ccp_aes_rfc3686_decrypt, 225 .min_keysize = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE, 226 .max_keysize = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE, 227 .init = ccp_aes_rfc3686_init_tfm, 228 229 .base.cra_flags = CRYPTO_ALG_ASYNC | 230 CRYPTO_ALG_ALLOCATES_MEMORY | 231 CRYPTO_ALG_KERN_DRIVER_ONLY | 232 CRYPTO_ALG_NEED_FALLBACK, 233 .base.cra_blocksize = CTR_RFC3686_BLOCK_SIZE, 234 .base.cra_ctxsize = sizeof(struct ccp_ctx), 235 .base.cra_priority = CCP_CRA_PRIORITY, 236 .base.cra_module = THIS_MODULE, 237 }; 238 239 struct ccp_aes_def { 240 enum ccp_aes_mode mode; 241 unsigned int version; 242 const char *name; 243 const char *driver_name; 244 unsigned int blocksize; 245 unsigned int ivsize; 246 const struct skcipher_alg *alg_defaults; 247 }; 248 249 static struct ccp_aes_def aes_algs[] = { 250 { 251 .mode = CCP_AES_MODE_ECB, 252 .version = CCP_VERSION(3, 0), 253 .name = "ecb(aes)", 254 .driver_name = "ecb-aes-ccp", 255 .blocksize = AES_BLOCK_SIZE, 256 .ivsize = 0, 257 .alg_defaults = &ccp_aes_defaults, 258 }, 259 { 260 .mode = CCP_AES_MODE_CBC, 261 .version = CCP_VERSION(3, 0), 262 .name = "cbc(aes)", 263 .driver_name = "cbc-aes-ccp", 264 .blocksize = AES_BLOCK_SIZE, 265 .ivsize = AES_BLOCK_SIZE, 266 .alg_defaults = &ccp_aes_defaults, 267 }, 268 { 269 .mode = CCP_AES_MODE_CFB, 270 .version = CCP_VERSION(3, 0), 271 .name = "cfb(aes)", 272 .driver_name = "cfb-aes-ccp", 273 .blocksize = 1, 274 .ivsize = AES_BLOCK_SIZE, 275 .alg_defaults = &ccp_aes_defaults, 276 }, 277 { 278 .mode = CCP_AES_MODE_OFB, 279 .version = CCP_VERSION(3, 0), 280 .name = "ofb(aes)", 281 .driver_name = "ofb-aes-ccp", 282 .blocksize = 1, 283 .ivsize = AES_BLOCK_SIZE, 284 .alg_defaults = &ccp_aes_defaults, 285 }, 286 { 287 .mode = CCP_AES_MODE_CTR, 288 .version = CCP_VERSION(3, 0), 289 .name = "ctr(aes)", 290 .driver_name = "ctr-aes-ccp", 291 .blocksize = 1, 292 .ivsize = AES_BLOCK_SIZE, 293 .alg_defaults = &ccp_aes_defaults, 294 }, 295 { 296 .mode = CCP_AES_MODE_CTR, 297 .version = CCP_VERSION(3, 0), 298 .name = "rfc3686(ctr(aes))", 299 .driver_name = "rfc3686-ctr-aes-ccp", 300 .blocksize = 1, 301 .ivsize = CTR_RFC3686_IV_SIZE, 302 .alg_defaults = &ccp_aes_rfc3686_defaults, 303 }, 304 }; 305 306 static int ccp_register_aes_alg(struct list_head *head, 307 const struct ccp_aes_def *def) 308 { 309 struct ccp_crypto_skcipher_alg *ccp_alg; 310 struct skcipher_alg *alg; 311 int ret; 312 313 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 314 if (!ccp_alg) 315 return -ENOMEM; 316 317 INIT_LIST_HEAD(&ccp_alg->entry); 318 319 ccp_alg->mode = def->mode; 320 321 /* Copy the defaults and override as necessary */ 322 alg = &ccp_alg->alg; 323 *alg = *def->alg_defaults; 324 snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name); 325 snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s", 326 def->driver_name); 327 alg->base.cra_blocksize = def->blocksize; 328 alg->ivsize = def->ivsize; 329 330 ret = crypto_register_skcipher(alg); 331 if (ret) { 332 pr_err("%s skcipher algorithm registration error (%d)\n", 333 alg->base.cra_name, ret); 334 kfree(ccp_alg); 335 return ret; 336 } 337 338 list_add(&ccp_alg->entry, head); 339 340 return 0; 341 } 342 343 int ccp_register_aes_algs(struct list_head *head) 344 { 345 int i, ret; 346 unsigned int ccpversion = ccp_version(); 347 348 for (i = 0; i < ARRAY_SIZE(aes_algs); i++) { 349 if (aes_algs[i].version > ccpversion) 350 continue; 351 ret = ccp_register_aes_alg(head, &aes_algs[i]); 352 if (ret) 353 return ret; 354 } 355 356 return 0; 357 } 358