2 * AMD Cryptographic Coprocessor (CCP) AES CMAC crypto API support
4 * Copyright (C) 2013 Advanced Micro Devices, Inc.
6 * Author: Tom Lendacky <thomas.lendacky@amd.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/module.h>
14 #include <linux/sched.h>
15 #include <linux/delay.h>
16 #include <linux/scatterlist.h>
17 #include <linux/crypto.h>
18 #include <crypto/algapi.h>
19 #include <crypto/aes.h>
20 #include <crypto/hash.h>
21 #include <crypto/internal/hash.h>
22 #include <crypto/scatterwalk.h>
24 #include "ccp-crypto.h"
27 static int ccp_aes_cmac_complete(struct crypto_async_request *async_req,
30 struct ahash_request *req = ahash_request_cast(async_req);
31 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
32 struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx(req);
33 unsigned int digest_size = crypto_ahash_digestsize(tfm);
39 /* Save remaining data to buffer */
40 scatterwalk_map_and_copy(rctx->buf, rctx->cmd.u.aes.src,
41 rctx->hash_cnt, rctx->hash_rem, 0);
42 rctx->buf_count = rctx->hash_rem;
46 memcpy(req->result, rctx->iv, digest_size);
49 sg_free_table(&rctx->data_sg);
54 static int ccp_do_cmac_update(struct ahash_request *req, unsigned int nbytes,
57 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
58 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
59 struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx(req);
60 struct scatterlist *sg, *cmac_key_sg = NULL;
61 unsigned int block_size =
62 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
63 unsigned int len, need_pad, sg_count;
66 if (!ctx->u.aes.key_len) {
67 pr_err("AES key not set\n");
74 if (!final && ((nbytes + rctx->buf_count) <= block_size)) {
75 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,
77 rctx->buf_count += nbytes;
82 len = rctx->buf_count + nbytes;
85 rctx->hash_cnt = final ? len : len & ~(block_size - 1);
86 rctx->hash_rem = final ? 0 : len & (block_size - 1);
87 if (!final && (rctx->hash_cnt == len)) {
88 /* CCP can't do zero length final, so keep some data around */
89 rctx->hash_cnt -= block_size;
90 rctx->hash_rem = block_size;
93 if (final && (rctx->null_msg || (len & (block_size - 1))))
98 sg_init_one(&rctx->iv_sg, rctx->iv, sizeof(rctx->iv));
100 /* Build the data scatterlist table - allocate enough entries for all
101 * possible data pieces (buffer, input data, padding)
103 sg_count = (nbytes) ? sg_nents(req->src) + 2 : 2;
104 ret = sg_alloc_table(&rctx->data_sg, sg_count, GFP_KERNEL);
109 if (rctx->buf_count) {
110 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
111 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg);
115 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src);
118 int pad_length = block_size - (len & (block_size - 1));
120 rctx->hash_cnt += pad_length;
122 memset(rctx->pad, 0, sizeof(rctx->pad));
124 sg_init_one(&rctx->pad_sg, rctx->pad, pad_length);
125 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->pad_sg);
130 /* Initialize the K1/K2 scatterlist */
132 cmac_key_sg = (need_pad) ? &ctx->u.aes.k2_sg
135 memset(&rctx->cmd, 0, sizeof(rctx->cmd));
136 INIT_LIST_HEAD(&rctx->cmd.entry);
137 rctx->cmd.engine = CCP_ENGINE_AES;
138 rctx->cmd.u.aes.type = ctx->u.aes.type;
139 rctx->cmd.u.aes.mode = ctx->u.aes.mode;
140 rctx->cmd.u.aes.action = CCP_AES_ACTION_ENCRYPT;
141 rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;
142 rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;
143 rctx->cmd.u.aes.iv = &rctx->iv_sg;
144 rctx->cmd.u.aes.iv_len = AES_BLOCK_SIZE;
145 rctx->cmd.u.aes.src = (sg) ? rctx->data_sg.sgl : NULL;
146 rctx->cmd.u.aes.src_len = rctx->hash_cnt;
147 rctx->cmd.u.aes.dst = NULL;
148 rctx->cmd.u.aes.cmac_key = cmac_key_sg;
149 rctx->cmd.u.aes.cmac_key_len = ctx->u.aes.kn_len;
150 rctx->cmd.u.aes.cmac_final = final;
152 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
157 static int ccp_aes_cmac_init(struct ahash_request *req)
159 struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx(req);
161 memset(rctx, 0, sizeof(*rctx));
168 static int ccp_aes_cmac_update(struct ahash_request *req)
170 return ccp_do_cmac_update(req, req->nbytes, 0);
173 static int ccp_aes_cmac_final(struct ahash_request *req)
175 return ccp_do_cmac_update(req, 0, 1);
178 static int ccp_aes_cmac_finup(struct ahash_request *req)
180 return ccp_do_cmac_update(req, req->nbytes, 1);
183 static int ccp_aes_cmac_digest(struct ahash_request *req)
187 ret = ccp_aes_cmac_init(req);
191 return ccp_do_cmac_update(req, req->nbytes, 1);
194 static int ccp_aes_cmac_setkey(struct crypto_ahash *tfm, const u8 *key,
195 unsigned int key_len)
197 struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm));
198 struct ccp_crypto_ahash_alg *alg =
199 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm));
200 u64 k0_hi, k0_lo, k1_hi, k1_lo, k2_hi, k2_lo;
201 u64 rb_hi = 0x00, rb_lo = 0x87;
206 case AES_KEYSIZE_128:
207 ctx->u.aes.type = CCP_AES_TYPE_128;
209 case AES_KEYSIZE_192:
210 ctx->u.aes.type = CCP_AES_TYPE_192;
212 case AES_KEYSIZE_256:
213 ctx->u.aes.type = CCP_AES_TYPE_256;
216 crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
219 ctx->u.aes.mode = alg->mode;
221 /* Set to zero until complete */
222 ctx->u.aes.key_len = 0;
224 /* Set the key for the AES cipher used to generate the keys */
225 ret = crypto_cipher_setkey(ctx->u.aes.tfm_cipher, key, key_len);
229 /* Encrypt a block of zeroes - use key area in context */
230 memset(ctx->u.aes.key, 0, sizeof(ctx->u.aes.key));
231 crypto_cipher_encrypt_one(ctx->u.aes.tfm_cipher, ctx->u.aes.key,
234 /* Generate K1 and K2 */
235 k0_hi = be64_to_cpu(*((__be64 *)ctx->u.aes.key));
236 k0_lo = be64_to_cpu(*((__be64 *)ctx->u.aes.key + 1));
238 k1_hi = (k0_hi << 1) | (k0_lo >> 63);
240 if (ctx->u.aes.key[0] & 0x80) {
244 gk = (__be64 *)ctx->u.aes.k1;
245 *gk = cpu_to_be64(k1_hi);
247 *gk = cpu_to_be64(k1_lo);
249 k2_hi = (k1_hi << 1) | (k1_lo >> 63);
251 if (ctx->u.aes.k1[0] & 0x80) {
255 gk = (__be64 *)ctx->u.aes.k2;
256 *gk = cpu_to_be64(k2_hi);
258 *gk = cpu_to_be64(k2_lo);
260 ctx->u.aes.kn_len = sizeof(ctx->u.aes.k1);
261 sg_init_one(&ctx->u.aes.k1_sg, ctx->u.aes.k1, sizeof(ctx->u.aes.k1));
262 sg_init_one(&ctx->u.aes.k2_sg, ctx->u.aes.k2, sizeof(ctx->u.aes.k2));
264 /* Save the supplied key */
265 memset(ctx->u.aes.key, 0, sizeof(ctx->u.aes.key));
266 memcpy(ctx->u.aes.key, key, key_len);
267 ctx->u.aes.key_len = key_len;
268 sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
273 static int ccp_aes_cmac_cra_init(struct crypto_tfm *tfm)
275 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
276 struct crypto_ahash *ahash = __crypto_ahash_cast(tfm);
277 struct crypto_cipher *cipher_tfm;
279 ctx->complete = ccp_aes_cmac_complete;
280 ctx->u.aes.key_len = 0;
282 crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_aes_cmac_req_ctx));
284 cipher_tfm = crypto_alloc_cipher("aes", 0,
285 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
286 if (IS_ERR(cipher_tfm)) {
287 pr_warn("could not load aes cipher driver\n");
288 return PTR_ERR(cipher_tfm);
290 ctx->u.aes.tfm_cipher = cipher_tfm;
295 static void ccp_aes_cmac_cra_exit(struct crypto_tfm *tfm)
297 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
299 if (ctx->u.aes.tfm_cipher)
300 crypto_free_cipher(ctx->u.aes.tfm_cipher);
301 ctx->u.aes.tfm_cipher = NULL;
304 int ccp_register_aes_cmac_algs(struct list_head *head)
306 struct ccp_crypto_ahash_alg *ccp_alg;
307 struct ahash_alg *alg;
308 struct hash_alg_common *halg;
309 struct crypto_alg *base;
312 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
316 INIT_LIST_HEAD(&ccp_alg->entry);
317 ccp_alg->mode = CCP_AES_MODE_CMAC;
320 alg->init = ccp_aes_cmac_init;
321 alg->update = ccp_aes_cmac_update;
322 alg->final = ccp_aes_cmac_final;
323 alg->finup = ccp_aes_cmac_finup;
324 alg->digest = ccp_aes_cmac_digest;
325 alg->setkey = ccp_aes_cmac_setkey;
328 halg->digestsize = AES_BLOCK_SIZE;
331 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "cmac(aes)");
332 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "cmac-aes-ccp");
333 base->cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC |
334 CRYPTO_ALG_KERN_DRIVER_ONLY |
335 CRYPTO_ALG_NEED_FALLBACK;
336 base->cra_blocksize = AES_BLOCK_SIZE;
337 base->cra_ctxsize = sizeof(struct ccp_ctx);
338 base->cra_priority = CCP_CRA_PRIORITY;
339 base->cra_type = &crypto_ahash_type;
340 base->cra_init = ccp_aes_cmac_cra_init;
341 base->cra_exit = ccp_aes_cmac_cra_exit;
342 base->cra_module = THIS_MODULE;
344 ret = crypto_register_ahash(alg);
346 pr_err("%s ahash algorithm registration error (%d)\n",
347 base->cra_name, ret);
352 list_add(&ccp_alg->entry, head);