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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * AMD Cryptographic Coprocessor (CCP) AES CMAC crypto API support4 *5 * Copyright (C) 2013,2018 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/hash.h>18#include <crypto/internal/hash.h>19#include <crypto/scatterwalk.h>20 21#include "ccp-crypto.h"22 23static int ccp_aes_cmac_complete(struct crypto_async_request *async_req,24 int ret)25{26 struct ahash_request *req = ahash_request_cast(async_req);27 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);28 struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx_dma(req);29 unsigned int digest_size = crypto_ahash_digestsize(tfm);30 31 if (ret)32 goto e_free;33 34 if (rctx->hash_rem) {35 /* Save remaining data to buffer */36 unsigned int offset = rctx->nbytes - rctx->hash_rem;37 38 scatterwalk_map_and_copy(rctx->buf, rctx->src,39 offset, rctx->hash_rem, 0);40 rctx->buf_count = rctx->hash_rem;41 } else {42 rctx->buf_count = 0;43 }44 45 /* Update result area if supplied */46 if (req->result && rctx->final)47 memcpy(req->result, rctx->iv, digest_size);48 49e_free:50 sg_free_table(&rctx->data_sg);51 52 return ret;53}54 55static int ccp_do_cmac_update(struct ahash_request *req, unsigned int nbytes,56 unsigned int final)57{58 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);59 struct ccp_ctx *ctx = crypto_ahash_ctx_dma(tfm);60 struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx_dma(req);61 struct scatterlist *sg, *cmac_key_sg = NULL;62 unsigned int block_size =63 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));64 unsigned int need_pad, sg_count;65 gfp_t gfp;66 u64 len;67 int ret;68 69 if (!ctx->u.aes.key_len)70 return -EINVAL;71 72 if (nbytes)73 rctx->null_msg = 0;74 75 len = (u64)rctx->buf_count + (u64)nbytes;76 77 if (!final && (len <= block_size)) {78 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,79 0, nbytes, 0);80 rctx->buf_count += nbytes;81 82 return 0;83 }84 85 rctx->src = req->src;86 rctx->nbytes = nbytes;87 88 rctx->final = final;89 rctx->hash_rem = final ? 0 : len & (block_size - 1);90 rctx->hash_cnt = len - rctx->hash_rem;91 if (!final && !rctx->hash_rem) {92 /* CCP can't do zero length final, so keep some data around */93 rctx->hash_cnt -= block_size;94 rctx->hash_rem = block_size;95 }96 97 if (final && (rctx->null_msg || (len & (block_size - 1))))98 need_pad = 1;99 else100 need_pad = 0;101 102 sg_init_one(&rctx->iv_sg, rctx->iv, sizeof(rctx->iv));103 104 /* Build the data scatterlist table - allocate enough entries for all105 * possible data pieces (buffer, input data, padding)106 */107 sg_count = (nbytes) ? sg_nents(req->src) + 2 : 2;108 gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?109 GFP_KERNEL : GFP_ATOMIC;110 ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp);111 if (ret)112 return ret;113 114 sg = NULL;115 if (rctx->buf_count) {116 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);117 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg);118 if (!sg) {119 ret = -EINVAL;120 goto e_free;121 }122 }123 124 if (nbytes) {125 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src);126 if (!sg) {127 ret = -EINVAL;128 goto e_free;129 }130 }131 132 if (need_pad) {133 int pad_length = block_size - (len & (block_size - 1));134 135 rctx->hash_cnt += pad_length;136 137 memset(rctx->pad, 0, sizeof(rctx->pad));138 rctx->pad[0] = 0x80;139 sg_init_one(&rctx->pad_sg, rctx->pad, pad_length);140 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->pad_sg);141 if (!sg) {142 ret = -EINVAL;143 goto e_free;144 }145 }146 if (sg) {147 sg_mark_end(sg);148 sg = rctx->data_sg.sgl;149 }150 151 /* Initialize the K1/K2 scatterlist */152 if (final)153 cmac_key_sg = (need_pad) ? &ctx->u.aes.k2_sg154 : &ctx->u.aes.k1_sg;155 156 memset(&rctx->cmd, 0, sizeof(rctx->cmd));157 INIT_LIST_HEAD(&rctx->cmd.entry);158 rctx->cmd.engine = CCP_ENGINE_AES;159 rctx->cmd.u.aes.type = ctx->u.aes.type;160 rctx->cmd.u.aes.mode = ctx->u.aes.mode;161 rctx->cmd.u.aes.action = CCP_AES_ACTION_ENCRYPT;162 rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;163 rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;164 rctx->cmd.u.aes.iv = &rctx->iv_sg;165 rctx->cmd.u.aes.iv_len = AES_BLOCK_SIZE;166 rctx->cmd.u.aes.src = sg;167 rctx->cmd.u.aes.src_len = rctx->hash_cnt;168 rctx->cmd.u.aes.dst = NULL;169 rctx->cmd.u.aes.cmac_key = cmac_key_sg;170 rctx->cmd.u.aes.cmac_key_len = ctx->u.aes.kn_len;171 rctx->cmd.u.aes.cmac_final = final;172 173 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);174 175 return ret;176 177e_free:178 sg_free_table(&rctx->data_sg);179 180 return ret;181}182 183static int ccp_aes_cmac_init(struct ahash_request *req)184{185 struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx_dma(req);186 187 memset(rctx, 0, sizeof(*rctx));188 189 rctx->null_msg = 1;190 191 return 0;192}193 194static int ccp_aes_cmac_update(struct ahash_request *req)195{196 return ccp_do_cmac_update(req, req->nbytes, 0);197}198 199static int ccp_aes_cmac_final(struct ahash_request *req)200{201 return ccp_do_cmac_update(req, 0, 1);202}203 204static int ccp_aes_cmac_finup(struct ahash_request *req)205{206 return ccp_do_cmac_update(req, req->nbytes, 1);207}208 209static int ccp_aes_cmac_digest(struct ahash_request *req)210{211 int ret;212 213 ret = ccp_aes_cmac_init(req);214 if (ret)215 return ret;216 217 return ccp_aes_cmac_finup(req);218}219 220static int ccp_aes_cmac_export(struct ahash_request *req, void *out)221{222 struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx_dma(req);223 struct ccp_aes_cmac_exp_ctx state;224 225 /* Don't let anything leak to 'out' */226 memset(&state, 0, sizeof(state));227 228 state.null_msg = rctx->null_msg;229 memcpy(state.iv, rctx->iv, sizeof(state.iv));230 state.buf_count = rctx->buf_count;231 memcpy(state.buf, rctx->buf, sizeof(state.buf));232 233 /* 'out' may not be aligned so memcpy from local variable */234 memcpy(out, &state, sizeof(state));235 236 return 0;237}238 239static int ccp_aes_cmac_import(struct ahash_request *req, const void *in)240{241 struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx_dma(req);242 struct ccp_aes_cmac_exp_ctx state;243 244 /* 'in' may not be aligned so memcpy to local variable */245 memcpy(&state, in, sizeof(state));246 247 memset(rctx, 0, sizeof(*rctx));248 rctx->null_msg = state.null_msg;249 memcpy(rctx->iv, state.iv, sizeof(rctx->iv));250 rctx->buf_count = state.buf_count;251 memcpy(rctx->buf, state.buf, sizeof(rctx->buf));252 253 return 0;254}255 256static int ccp_aes_cmac_setkey(struct crypto_ahash *tfm, const u8 *key,257 unsigned int key_len)258{259 struct ccp_ctx *ctx = crypto_ahash_ctx_dma(tfm);260 struct ccp_crypto_ahash_alg *alg =261 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm));262 u64 k0_hi, k0_lo, k1_hi, k1_lo, k2_hi, k2_lo;263 u64 rb_hi = 0x00, rb_lo = 0x87;264 struct crypto_aes_ctx aes;265 __be64 *gk;266 int ret;267 268 switch (key_len) {269 case AES_KEYSIZE_128:270 ctx->u.aes.type = CCP_AES_TYPE_128;271 break;272 case AES_KEYSIZE_192:273 ctx->u.aes.type = CCP_AES_TYPE_192;274 break;275 case AES_KEYSIZE_256:276 ctx->u.aes.type = CCP_AES_TYPE_256;277 break;278 default:279 return -EINVAL;280 }281 ctx->u.aes.mode = alg->mode;282 283 /* Set to zero until complete */284 ctx->u.aes.key_len = 0;285 286 /* Set the key for the AES cipher used to generate the keys */287 ret = aes_expandkey(&aes, key, key_len);288 if (ret)289 return ret;290 291 /* Encrypt a block of zeroes - use key area in context */292 memset(ctx->u.aes.key, 0, sizeof(ctx->u.aes.key));293 aes_encrypt(&aes, ctx->u.aes.key, ctx->u.aes.key);294 memzero_explicit(&aes, sizeof(aes));295 296 /* Generate K1 and K2 */297 k0_hi = be64_to_cpu(*((__be64 *)ctx->u.aes.key));298 k0_lo = be64_to_cpu(*((__be64 *)ctx->u.aes.key + 1));299 300 k1_hi = (k0_hi << 1) | (k0_lo >> 63);301 k1_lo = k0_lo << 1;302 if (ctx->u.aes.key[0] & 0x80) {303 k1_hi ^= rb_hi;304 k1_lo ^= rb_lo;305 }306 gk = (__be64 *)ctx->u.aes.k1;307 *gk = cpu_to_be64(k1_hi);308 gk++;309 *gk = cpu_to_be64(k1_lo);310 311 k2_hi = (k1_hi << 1) | (k1_lo >> 63);312 k2_lo = k1_lo << 1;313 if (ctx->u.aes.k1[0] & 0x80) {314 k2_hi ^= rb_hi;315 k2_lo ^= rb_lo;316 }317 gk = (__be64 *)ctx->u.aes.k2;318 *gk = cpu_to_be64(k2_hi);319 gk++;320 *gk = cpu_to_be64(k2_lo);321 322 ctx->u.aes.kn_len = sizeof(ctx->u.aes.k1);323 sg_init_one(&ctx->u.aes.k1_sg, ctx->u.aes.k1, sizeof(ctx->u.aes.k1));324 sg_init_one(&ctx->u.aes.k2_sg, ctx->u.aes.k2, sizeof(ctx->u.aes.k2));325 326 /* Save the supplied key */327 memset(ctx->u.aes.key, 0, sizeof(ctx->u.aes.key));328 memcpy(ctx->u.aes.key, key, key_len);329 ctx->u.aes.key_len = key_len;330 sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);331 332 return ret;333}334 335static int ccp_aes_cmac_cra_init(struct crypto_tfm *tfm)336{337 struct ccp_ctx *ctx = crypto_tfm_ctx_dma(tfm);338 struct crypto_ahash *ahash = __crypto_ahash_cast(tfm);339 340 ctx->complete = ccp_aes_cmac_complete;341 ctx->u.aes.key_len = 0;342 343 crypto_ahash_set_reqsize_dma(ahash,344 sizeof(struct ccp_aes_cmac_req_ctx));345 346 return 0;347}348 349int ccp_register_aes_cmac_algs(struct list_head *head)350{351 struct ccp_crypto_ahash_alg *ccp_alg;352 struct ahash_alg *alg;353 struct hash_alg_common *halg;354 struct crypto_alg *base;355 int ret;356 357 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);358 if (!ccp_alg)359 return -ENOMEM;360 361 INIT_LIST_HEAD(&ccp_alg->entry);362 ccp_alg->mode = CCP_AES_MODE_CMAC;363 364 alg = &ccp_alg->alg;365 alg->init = ccp_aes_cmac_init;366 alg->update = ccp_aes_cmac_update;367 alg->final = ccp_aes_cmac_final;368 alg->finup = ccp_aes_cmac_finup;369 alg->digest = ccp_aes_cmac_digest;370 alg->export = ccp_aes_cmac_export;371 alg->import = ccp_aes_cmac_import;372 alg->setkey = ccp_aes_cmac_setkey;373 374 halg = &alg->halg;375 halg->digestsize = AES_BLOCK_SIZE;376 halg->statesize = sizeof(struct ccp_aes_cmac_exp_ctx);377 378 base = &halg->base;379 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "cmac(aes)");380 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "cmac-aes-ccp");381 base->cra_flags = CRYPTO_ALG_ASYNC |382 CRYPTO_ALG_ALLOCATES_MEMORY |383 CRYPTO_ALG_KERN_DRIVER_ONLY |384 CRYPTO_ALG_NEED_FALLBACK;385 base->cra_blocksize = AES_BLOCK_SIZE;386 base->cra_ctxsize = sizeof(struct ccp_ctx) + crypto_dma_padding();387 base->cra_priority = CCP_CRA_PRIORITY;388 base->cra_init = ccp_aes_cmac_cra_init;389 base->cra_module = THIS_MODULE;390 391 ret = crypto_register_ahash(alg);392 if (ret) {393 pr_err("%s ahash algorithm registration error (%d)\n",394 base->cra_name, ret);395 kfree(ccp_alg);396 return ret;397 }398 399 list_add(&ccp_alg->entry, head);400 401 return 0;402}403