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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * AMD Cryptographic Coprocessor (CCP) AES GCM crypto API support4 *5 * Copyright (C) 2016,2017 Advanced Micro Devices, Inc.6 *7 * Author: Gary R Hook <gary.hook@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/internal/aead.h>16#include <crypto/algapi.h>17#include <crypto/aes.h>18#include <crypto/ctr.h>19#include <crypto/gcm.h>20#include <crypto/scatterwalk.h>21 22#include "ccp-crypto.h"23 24static int ccp_aes_gcm_complete(struct crypto_async_request *async_req, int ret)25{26 return ret;27}28 29static int ccp_aes_gcm_setkey(struct crypto_aead *tfm, const u8 *key,30 unsigned int key_len)31{32 struct ccp_ctx *ctx = crypto_aead_ctx_dma(tfm);33 34 switch (key_len) {35 case AES_KEYSIZE_128:36 ctx->u.aes.type = CCP_AES_TYPE_128;37 break;38 case AES_KEYSIZE_192:39 ctx->u.aes.type = CCP_AES_TYPE_192;40 break;41 case AES_KEYSIZE_256:42 ctx->u.aes.type = CCP_AES_TYPE_256;43 break;44 default:45 return -EINVAL;46 }47 48 ctx->u.aes.mode = CCP_AES_MODE_GCM;49 ctx->u.aes.key_len = key_len;50 51 memcpy(ctx->u.aes.key, key, key_len);52 sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);53 54 return 0;55}56 57static int ccp_aes_gcm_setauthsize(struct crypto_aead *tfm,58 unsigned int authsize)59{60 switch (authsize) {61 case 16:62 case 15:63 case 14:64 case 13:65 case 12:66 case 8:67 case 4:68 break;69 default:70 return -EINVAL;71 }72 73 return 0;74}75 76static int ccp_aes_gcm_crypt(struct aead_request *req, bool encrypt)77{78 struct crypto_aead *tfm = crypto_aead_reqtfm(req);79 struct ccp_ctx *ctx = crypto_aead_ctx_dma(tfm);80 struct ccp_aes_req_ctx *rctx = aead_request_ctx_dma(req);81 struct scatterlist *iv_sg = NULL;82 unsigned int iv_len = 0;83 int i;84 int ret = 0;85 86 if (!ctx->u.aes.key_len)87 return -EINVAL;88 89 if (ctx->u.aes.mode != CCP_AES_MODE_GCM)90 return -EINVAL;91 92 if (!req->iv)93 return -EINVAL;94 95 /*96 * 5 parts:97 * plaintext/ciphertext input98 * AAD99 * key100 * IV101 * Destination+tag buffer102 */103 104 /* Prepare the IV: 12 bytes + an integer (counter) */105 memcpy(rctx->iv, req->iv, GCM_AES_IV_SIZE);106 for (i = 0; i < 3; i++)107 rctx->iv[i + GCM_AES_IV_SIZE] = 0;108 rctx->iv[AES_BLOCK_SIZE - 1] = 1;109 110 /* Set up a scatterlist for the IV */111 iv_sg = &rctx->iv_sg;112 iv_len = AES_BLOCK_SIZE;113 sg_init_one(iv_sg, rctx->iv, iv_len);114 115 /* The AAD + plaintext are concatenated in the src buffer */116 memset(&rctx->cmd, 0, sizeof(rctx->cmd));117 INIT_LIST_HEAD(&rctx->cmd.entry);118 rctx->cmd.engine = CCP_ENGINE_AES;119 rctx->cmd.u.aes.authsize = crypto_aead_authsize(tfm);120 rctx->cmd.u.aes.type = ctx->u.aes.type;121 rctx->cmd.u.aes.mode = ctx->u.aes.mode;122 rctx->cmd.u.aes.action = encrypt;123 rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;124 rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;125 rctx->cmd.u.aes.iv = iv_sg;126 rctx->cmd.u.aes.iv_len = iv_len;127 rctx->cmd.u.aes.src = req->src;128 rctx->cmd.u.aes.src_len = req->cryptlen;129 rctx->cmd.u.aes.aad_len = req->assoclen;130 131 /* The cipher text + the tag are in the dst buffer */132 rctx->cmd.u.aes.dst = req->dst;133 134 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);135 136 return ret;137}138 139static int ccp_aes_gcm_encrypt(struct aead_request *req)140{141 return ccp_aes_gcm_crypt(req, CCP_AES_ACTION_ENCRYPT);142}143 144static int ccp_aes_gcm_decrypt(struct aead_request *req)145{146 return ccp_aes_gcm_crypt(req, CCP_AES_ACTION_DECRYPT);147}148 149static int ccp_aes_gcm_cra_init(struct crypto_aead *tfm)150{151 struct ccp_ctx *ctx = crypto_aead_ctx_dma(tfm);152 153 ctx->complete = ccp_aes_gcm_complete;154 ctx->u.aes.key_len = 0;155 156 crypto_aead_set_reqsize_dma(tfm, sizeof(struct ccp_aes_req_ctx));157 158 return 0;159}160 161static void ccp_aes_gcm_cra_exit(struct crypto_tfm *tfm)162{163}164 165static struct aead_alg ccp_aes_gcm_defaults = {166 .setkey = ccp_aes_gcm_setkey,167 .setauthsize = ccp_aes_gcm_setauthsize,168 .encrypt = ccp_aes_gcm_encrypt,169 .decrypt = ccp_aes_gcm_decrypt,170 .init = ccp_aes_gcm_cra_init,171 .ivsize = GCM_AES_IV_SIZE,172 .maxauthsize = AES_BLOCK_SIZE,173 .base = {174 .cra_flags = CRYPTO_ALG_ASYNC |175 CRYPTO_ALG_ALLOCATES_MEMORY |176 CRYPTO_ALG_KERN_DRIVER_ONLY |177 CRYPTO_ALG_NEED_FALLBACK,178 .cra_blocksize = AES_BLOCK_SIZE,179 .cra_ctxsize = sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,180 .cra_priority = CCP_CRA_PRIORITY,181 .cra_exit = ccp_aes_gcm_cra_exit,182 .cra_module = THIS_MODULE,183 },184};185 186struct ccp_aes_aead_def {187 enum ccp_aes_mode mode;188 unsigned int version;189 const char *name;190 const char *driver_name;191 unsigned int blocksize;192 unsigned int ivsize;193 struct aead_alg *alg_defaults;194};195 196static struct ccp_aes_aead_def aes_aead_algs[] = {197 {198 .mode = CCP_AES_MODE_GHASH,199 .version = CCP_VERSION(5, 0),200 .name = "gcm(aes)",201 .driver_name = "gcm-aes-ccp",202 .blocksize = 1,203 .ivsize = AES_BLOCK_SIZE,204 .alg_defaults = &ccp_aes_gcm_defaults,205 },206};207 208static int ccp_register_aes_aead(struct list_head *head,209 const struct ccp_aes_aead_def *def)210{211 struct ccp_crypto_aead *ccp_aead;212 struct aead_alg *alg;213 int ret;214 215 ccp_aead = kzalloc(sizeof(*ccp_aead), GFP_KERNEL);216 if (!ccp_aead)217 return -ENOMEM;218 219 INIT_LIST_HEAD(&ccp_aead->entry);220 221 ccp_aead->mode = def->mode;222 223 /* Copy the defaults and override as necessary */224 alg = &ccp_aead->alg;225 *alg = *def->alg_defaults;226 snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);227 snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",228 def->driver_name);229 alg->base.cra_blocksize = def->blocksize;230 231 ret = crypto_register_aead(alg);232 if (ret) {233 pr_err("%s aead algorithm registration error (%d)\n",234 alg->base.cra_name, ret);235 kfree(ccp_aead);236 return ret;237 }238 239 list_add(&ccp_aead->entry, head);240 241 return 0;242}243 244int ccp_register_aes_aeads(struct list_head *head)245{246 int i, ret;247 unsigned int ccpversion = ccp_version();248 249 for (i = 0; i < ARRAY_SIZE(aes_aead_algs); i++) {250 if (aes_aead_algs[i].version > ccpversion)251 continue;252 ret = ccp_register_aes_aead(head, &aes_aead_algs[i]);253 if (ret)254 return ret;255 }256 257 return 0;258}259