1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AMD Cryptographic Coprocessor (CCP) crypto API support 4 * 5 * Copyright (C) 2013,2017 Advanced Micro Devices, Inc. 6 * 7 * Author: Tom Lendacky <thomas.lendacky@amd.com> 8 */ 9 10 #include <linux/module.h> 11 #include <linux/moduleparam.h> 12 #include <linux/kernel.h> 13 #include <linux/list.h> 14 #include <linux/ccp.h> 15 #include <linux/scatterlist.h> 16 #include <crypto/internal/hash.h> 17 #include <crypto/internal/akcipher.h> 18 19 #include "ccp-crypto.h" 20 21 MODULE_AUTHOR("Tom Lendacky <thomas.lendacky@amd.com>"); 22 MODULE_LICENSE("GPL"); 23 MODULE_VERSION("1.0.0"); 24 MODULE_DESCRIPTION("AMD Cryptographic Coprocessor crypto API support"); 25 26 static unsigned int aes_disable; 27 module_param(aes_disable, uint, 0444); 28 MODULE_PARM_DESC(aes_disable, "Disable use of AES - any non-zero value"); 29 30 static unsigned int sha_disable; 31 module_param(sha_disable, uint, 0444); 32 MODULE_PARM_DESC(sha_disable, "Disable use of SHA - any non-zero value"); 33 34 static unsigned int des3_disable; 35 module_param(des3_disable, uint, 0444); 36 MODULE_PARM_DESC(des3_disable, "Disable use of 3DES - any non-zero value"); 37 38 static unsigned int rsa_disable; 39 module_param(rsa_disable, uint, 0444); 40 MODULE_PARM_DESC(rsa_disable, "Disable use of RSA - any non-zero value"); 41 42 /* List heads for the supported algorithms */ 43 static LIST_HEAD(hash_algs); 44 static LIST_HEAD(skcipher_algs); 45 static LIST_HEAD(aead_algs); 46 static LIST_HEAD(akcipher_algs); 47 48 /* For any tfm, requests for that tfm must be returned on the order 49 * received. With multiple queues available, the CCP can process more 50 * than one cmd at a time. Therefore we must maintain a cmd list to insure 51 * the proper ordering of requests on a given tfm. 52 */ 53 struct ccp_crypto_queue { 54 struct list_head cmds; 55 struct list_head *backlog; 56 unsigned int cmd_count; 57 }; 58 59 #define CCP_CRYPTO_MAX_QLEN 100 60 61 static struct ccp_crypto_queue req_queue; 62 static DEFINE_SPINLOCK(req_queue_lock); 63 64 struct ccp_crypto_cmd { 65 struct list_head entry; 66 67 struct ccp_cmd *cmd; 68 69 /* Save the crypto_tfm and crypto_async_request addresses 70 * separately to avoid any reference to a possibly invalid 71 * crypto_async_request structure after invoking the request 72 * callback 73 */ 74 struct crypto_async_request *req; 75 struct crypto_tfm *tfm; 76 77 /* Used for held command processing to determine state */ 78 int ret; 79 }; 80 81 static inline bool ccp_crypto_success(int err) 82 { 83 if (err && (err != -EINPROGRESS) && (err != -EBUSY)) 84 return false; 85 86 return true; 87 } 88 89 static struct ccp_crypto_cmd *ccp_crypto_cmd_complete( 90 struct ccp_crypto_cmd *crypto_cmd, struct ccp_crypto_cmd **backlog) 91 { 92 struct ccp_crypto_cmd *held = NULL, *tmp; 93 unsigned long flags; 94 95 *backlog = NULL; 96 97 spin_lock_irqsave(&req_queue_lock, flags); 98 99 /* Held cmds will be after the current cmd in the queue so start 100 * searching for a cmd with a matching tfm for submission. 101 */ 102 tmp = crypto_cmd; 103 list_for_each_entry_continue(tmp, &req_queue.cmds, entry) { 104 if (crypto_cmd->tfm != tmp->tfm) 105 continue; 106 held = tmp; 107 break; 108 } 109 110 /* Process the backlog: 111 * Because cmds can be executed from any point in the cmd list 112 * special precautions have to be taken when handling the backlog. 113 */ 114 if (req_queue.backlog != &req_queue.cmds) { 115 /* Skip over this cmd if it is the next backlog cmd */ 116 if (req_queue.backlog == &crypto_cmd->entry) 117 req_queue.backlog = crypto_cmd->entry.next; 118 119 *backlog = container_of(req_queue.backlog, 120 struct ccp_crypto_cmd, entry); 121 req_queue.backlog = req_queue.backlog->next; 122 123 /* Skip over this cmd if it is now the next backlog cmd */ 124 if (req_queue.backlog == &crypto_cmd->entry) 125 req_queue.backlog = crypto_cmd->entry.next; 126 } 127 128 /* Remove the cmd entry from the list of cmds */ 129 req_queue.cmd_count--; 130 list_del(&crypto_cmd->entry); 131 132 spin_unlock_irqrestore(&req_queue_lock, flags); 133 134 return held; 135 } 136 137 static void ccp_crypto_complete(void *data, int err) 138 { 139 struct ccp_crypto_cmd *crypto_cmd = data; 140 struct ccp_crypto_cmd *held, *next, *backlog; 141 struct crypto_async_request *req = crypto_cmd->req; 142 struct ccp_ctx *ctx = crypto_tfm_ctx_dma(req->tfm); 143 int ret; 144 145 if (err == -EINPROGRESS) { 146 /* Only propagate the -EINPROGRESS if necessary */ 147 if (crypto_cmd->ret == -EBUSY) { 148 crypto_cmd->ret = -EINPROGRESS; 149 req->complete(req, -EINPROGRESS); 150 } 151 152 return; 153 } 154 155 /* Operation has completed - update the queue before invoking 156 * the completion callbacks and retrieve the next cmd (cmd with 157 * a matching tfm) that can be submitted to the CCP. 158 */ 159 held = ccp_crypto_cmd_complete(crypto_cmd, &backlog); 160 if (backlog) { 161 backlog->ret = -EINPROGRESS; 162 backlog->req->complete(backlog->req, -EINPROGRESS); 163 } 164 165 /* Transition the state from -EBUSY to -EINPROGRESS first */ 166 if (crypto_cmd->ret == -EBUSY) 167 req->complete(req, -EINPROGRESS); 168 169 /* Completion callbacks */ 170 ret = err; 171 if (ctx->complete) 172 ret = ctx->complete(req, ret); 173 req->complete(req, ret); 174 175 /* Submit the next cmd */ 176 while (held) { 177 /* Since we have already queued the cmd, we must indicate that 178 * we can backlog so as not to "lose" this request. 179 */ 180 held->cmd->flags |= CCP_CMD_MAY_BACKLOG; 181 ret = ccp_enqueue_cmd(held->cmd); 182 if (ccp_crypto_success(ret)) 183 break; 184 185 /* Error occurred, report it and get the next entry */ 186 ctx = crypto_tfm_ctx_dma(held->req->tfm); 187 if (ctx->complete) 188 ret = ctx->complete(held->req, ret); 189 held->req->complete(held->req, ret); 190 191 next = ccp_crypto_cmd_complete(held, &backlog); 192 if (backlog) { 193 backlog->ret = -EINPROGRESS; 194 backlog->req->complete(backlog->req, -EINPROGRESS); 195 } 196 197 kfree(held); 198 held = next; 199 } 200 201 kfree(crypto_cmd); 202 } 203 204 static int ccp_crypto_enqueue_cmd(struct ccp_crypto_cmd *crypto_cmd) 205 { 206 struct ccp_crypto_cmd *active = NULL, *tmp; 207 unsigned long flags; 208 bool free_cmd = true; 209 int ret; 210 211 spin_lock_irqsave(&req_queue_lock, flags); 212 213 /* Check if the cmd can/should be queued */ 214 if (req_queue.cmd_count >= CCP_CRYPTO_MAX_QLEN) { 215 if (!(crypto_cmd->cmd->flags & CCP_CMD_MAY_BACKLOG)) { 216 ret = -ENOSPC; 217 goto e_lock; 218 } 219 } 220 221 /* Look for an entry with the same tfm. If there is a cmd 222 * with the same tfm in the list then the current cmd cannot 223 * be submitted to the CCP yet. 224 */ 225 list_for_each_entry(tmp, &req_queue.cmds, entry) { 226 if (crypto_cmd->tfm != tmp->tfm) 227 continue; 228 active = tmp; 229 break; 230 } 231 232 ret = -EINPROGRESS; 233 if (!active) { 234 ret = ccp_enqueue_cmd(crypto_cmd->cmd); 235 if (!ccp_crypto_success(ret)) 236 goto e_lock; /* Error, don't queue it */ 237 } 238 239 if (req_queue.cmd_count >= CCP_CRYPTO_MAX_QLEN) { 240 ret = -EBUSY; 241 if (req_queue.backlog == &req_queue.cmds) 242 req_queue.backlog = &crypto_cmd->entry; 243 } 244 crypto_cmd->ret = ret; 245 246 req_queue.cmd_count++; 247 list_add_tail(&crypto_cmd->entry, &req_queue.cmds); 248 249 free_cmd = false; 250 251 e_lock: 252 spin_unlock_irqrestore(&req_queue_lock, flags); 253 254 if (free_cmd) 255 kfree(crypto_cmd); 256 257 return ret; 258 } 259 260 /** 261 * ccp_crypto_enqueue_request - queue an crypto async request for processing 262 * by the CCP 263 * 264 * @req: crypto_async_request struct to be processed 265 * @cmd: ccp_cmd struct to be sent to the CCP 266 */ 267 int ccp_crypto_enqueue_request(struct crypto_async_request *req, 268 struct ccp_cmd *cmd) 269 { 270 struct ccp_crypto_cmd *crypto_cmd; 271 gfp_t gfp; 272 273 gfp = req->flags & CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL : GFP_ATOMIC; 274 275 crypto_cmd = kzalloc(sizeof(*crypto_cmd), gfp); 276 if (!crypto_cmd) 277 return -ENOMEM; 278 279 /* The tfm pointer must be saved and not referenced from the 280 * crypto_async_request (req) pointer because it is used after 281 * completion callback for the request and the req pointer 282 * might not be valid anymore. 283 */ 284 crypto_cmd->cmd = cmd; 285 crypto_cmd->req = req; 286 crypto_cmd->tfm = req->tfm; 287 288 cmd->callback = ccp_crypto_complete; 289 cmd->data = crypto_cmd; 290 291 if (req->flags & CRYPTO_TFM_REQ_MAY_BACKLOG) 292 cmd->flags |= CCP_CMD_MAY_BACKLOG; 293 else 294 cmd->flags &= ~CCP_CMD_MAY_BACKLOG; 295 296 return ccp_crypto_enqueue_cmd(crypto_cmd); 297 } 298 299 struct scatterlist *ccp_crypto_sg_table_add(struct sg_table *table, 300 struct scatterlist *sg_add) 301 { 302 struct scatterlist *sg, *sg_last = NULL; 303 304 for (sg = table->sgl; sg; sg = sg_next(sg)) 305 if (!sg_page(sg)) 306 break; 307 if (WARN_ON(!sg)) 308 return NULL; 309 310 for (; sg && sg_add; sg = sg_next(sg), sg_add = sg_next(sg_add)) { 311 sg_set_page(sg, sg_page(sg_add), sg_add->length, 312 sg_add->offset); 313 sg_last = sg; 314 } 315 if (WARN_ON(sg_add)) 316 return NULL; 317 318 return sg_last; 319 } 320 321 static int ccp_register_algs(void) 322 { 323 int ret; 324 325 if (!aes_disable) { 326 ret = ccp_register_aes_algs(&skcipher_algs); 327 if (ret) 328 return ret; 329 330 ret = ccp_register_aes_cmac_algs(&hash_algs); 331 if (ret) 332 return ret; 333 334 ret = ccp_register_aes_xts_algs(&skcipher_algs); 335 if (ret) 336 return ret; 337 338 ret = ccp_register_aes_aeads(&aead_algs); 339 if (ret) 340 return ret; 341 } 342 343 if (!des3_disable) { 344 ret = ccp_register_des3_algs(&skcipher_algs); 345 if (ret) 346 return ret; 347 } 348 349 if (!sha_disable) { 350 ret = ccp_register_sha_algs(&hash_algs); 351 if (ret) 352 return ret; 353 } 354 355 if (!rsa_disable) { 356 ret = ccp_register_rsa_algs(&akcipher_algs); 357 if (ret) 358 return ret; 359 } 360 361 return 0; 362 } 363 364 static void ccp_unregister_algs(void) 365 { 366 struct ccp_crypto_ahash_alg *ahash_alg, *ahash_tmp; 367 struct ccp_crypto_skcipher_alg *ablk_alg, *ablk_tmp; 368 struct ccp_crypto_aead *aead_alg, *aead_tmp; 369 struct ccp_crypto_akcipher_alg *akc_alg, *akc_tmp; 370 371 list_for_each_entry_safe(ahash_alg, ahash_tmp, &hash_algs, entry) { 372 crypto_unregister_ahash(&ahash_alg->alg); 373 list_del(&ahash_alg->entry); 374 kfree(ahash_alg); 375 } 376 377 list_for_each_entry_safe(ablk_alg, ablk_tmp, &skcipher_algs, entry) { 378 crypto_unregister_skcipher(&ablk_alg->alg); 379 list_del(&ablk_alg->entry); 380 kfree(ablk_alg); 381 } 382 383 list_for_each_entry_safe(aead_alg, aead_tmp, &aead_algs, entry) { 384 crypto_unregister_aead(&aead_alg->alg); 385 list_del(&aead_alg->entry); 386 kfree(aead_alg); 387 } 388 389 list_for_each_entry_safe(akc_alg, akc_tmp, &akcipher_algs, entry) { 390 crypto_unregister_akcipher(&akc_alg->alg); 391 list_del(&akc_alg->entry); 392 kfree(akc_alg); 393 } 394 } 395 396 static int __init ccp_crypto_init(void) 397 { 398 int ret; 399 400 ret = ccp_present(); 401 if (ret) { 402 pr_err("Cannot load: there are no available CCPs\n"); 403 return ret; 404 } 405 406 INIT_LIST_HEAD(&req_queue.cmds); 407 req_queue.backlog = &req_queue.cmds; 408 req_queue.cmd_count = 0; 409 410 ret = ccp_register_algs(); 411 if (ret) 412 ccp_unregister_algs(); 413 414 return ret; 415 } 416 417 static void __exit ccp_crypto_exit(void) 418 { 419 ccp_unregister_algs(); 420 } 421 422 module_init(ccp_crypto_init); 423 module_exit(ccp_crypto_exit); 424