crypto: ccp - Add support for valid authsize values less than 16
[linux-2.6-block.git] / drivers / crypto / ccp / ccp-crypto-aes-galois.c
CommitLineData
600bac00 1// SPDX-License-Identifier: GPL-2.0
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2/*
3 * AMD Cryptographic Coprocessor (CCP) AES GCM crypto API support
4 *
68cc652f 5 * Copyright (C) 2016,2017 Advanced Micro Devices, Inc.
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6 *
7 * Author: Gary R Hook <gary.hook@amd.com>
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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>
cf0bd0ae 19#include <crypto/gcm.h>
36cf515b 20#include <crypto/scatterwalk.h>
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21
22#include "ccp-crypto.h"
23
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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(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 crypto_aead_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
46 return -EINVAL;
47 }
48
49 ctx->u.aes.mode = CCP_AES_MODE_GCM;
50 ctx->u.aes.key_len = key_len;
51
52 memcpy(ctx->u.aes.key, key, key_len);
53 sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
54
55 return 0;
56}
57
58static int ccp_aes_gcm_setauthsize(struct crypto_aead *tfm,
59 unsigned int authsize)
60{
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61 switch (authsize) {
62 case 16:
63 case 15:
64 case 14:
65 case 13:
66 case 12:
67 case 8:
68 case 4:
69 break;
70 default:
71 return -EINVAL;
72 }
73
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74 return 0;
75}
76
77static int ccp_aes_gcm_crypt(struct aead_request *req, bool encrypt)
78{
79 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
80 struct ccp_ctx *ctx = crypto_aead_ctx(tfm);
81 struct ccp_aes_req_ctx *rctx = aead_request_ctx(req);
82 struct scatterlist *iv_sg = NULL;
83 unsigned int iv_len = 0;
84 int i;
85 int ret = 0;
86
87 if (!ctx->u.aes.key_len)
88 return -EINVAL;
89
90 if (ctx->u.aes.mode != CCP_AES_MODE_GCM)
91 return -EINVAL;
92
93 if (!req->iv)
94 return -EINVAL;
95
96 /*
97 * 5 parts:
98 * plaintext/ciphertext input
99 * AAD
100 * key
101 * IV
102 * Destination+tag buffer
103 */
104
105 /* Prepare the IV: 12 bytes + an integer (counter) */
cf0bd0ae 106 memcpy(rctx->iv, req->iv, GCM_AES_IV_SIZE);
36cf515b 107 for (i = 0; i < 3; i++)
cf0bd0ae 108 rctx->iv[i + GCM_AES_IV_SIZE] = 0;
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109 rctx->iv[AES_BLOCK_SIZE - 1] = 1;
110
111 /* Set up a scatterlist for the IV */
112 iv_sg = &rctx->iv_sg;
113 iv_len = AES_BLOCK_SIZE;
114 sg_init_one(iv_sg, rctx->iv, iv_len);
115
116 /* The AAD + plaintext are concatenated in the src buffer */
117 memset(&rctx->cmd, 0, sizeof(rctx->cmd));
118 INIT_LIST_HEAD(&rctx->cmd.entry);
119 rctx->cmd.engine = CCP_ENGINE_AES;
9f00baf7 120 rctx->cmd.u.aes.authsize = crypto_aead_authsize(tfm);
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121 rctx->cmd.u.aes.type = ctx->u.aes.type;
122 rctx->cmd.u.aes.mode = ctx->u.aes.mode;
123 rctx->cmd.u.aes.action = encrypt;
124 rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;
125 rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;
126 rctx->cmd.u.aes.iv = iv_sg;
127 rctx->cmd.u.aes.iv_len = iv_len;
128 rctx->cmd.u.aes.src = req->src;
129 rctx->cmd.u.aes.src_len = req->cryptlen;
130 rctx->cmd.u.aes.aad_len = req->assoclen;
131
132 /* The cipher text + the tag are in the dst buffer */
133 rctx->cmd.u.aes.dst = req->dst;
134
135 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
136
137 return ret;
138}
139
140static int ccp_aes_gcm_encrypt(struct aead_request *req)
141{
142 return ccp_aes_gcm_crypt(req, CCP_AES_ACTION_ENCRYPT);
143}
144
145static int ccp_aes_gcm_decrypt(struct aead_request *req)
146{
147 return ccp_aes_gcm_crypt(req, CCP_AES_ACTION_DECRYPT);
148}
149
150static int ccp_aes_gcm_cra_init(struct crypto_aead *tfm)
151{
152 struct ccp_ctx *ctx = crypto_aead_ctx(tfm);
153
154 ctx->complete = ccp_aes_gcm_complete;
155 ctx->u.aes.key_len = 0;
156
157 crypto_aead_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx));
158
159 return 0;
160}
161
162static void ccp_aes_gcm_cra_exit(struct crypto_tfm *tfm)
163{
164}
165
166static struct aead_alg ccp_aes_gcm_defaults = {
167 .setkey = ccp_aes_gcm_setkey,
168 .setauthsize = ccp_aes_gcm_setauthsize,
169 .encrypt = ccp_aes_gcm_encrypt,
170 .decrypt = ccp_aes_gcm_decrypt,
171 .init = ccp_aes_gcm_cra_init,
cf0bd0ae 172 .ivsize = GCM_AES_IV_SIZE,
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173 .maxauthsize = AES_BLOCK_SIZE,
174 .base = {
175 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
176 CRYPTO_ALG_ASYNC |
177 CRYPTO_ALG_KERN_DRIVER_ONLY |
178 CRYPTO_ALG_NEED_FALLBACK,
179 .cra_blocksize = AES_BLOCK_SIZE,
180 .cra_ctxsize = sizeof(struct ccp_ctx),
181 .cra_priority = CCP_CRA_PRIORITY,
182 .cra_type = &crypto_ablkcipher_type,
183 .cra_exit = ccp_aes_gcm_cra_exit,
184 .cra_module = THIS_MODULE,
185 },
186};
187
188struct ccp_aes_aead_def {
189 enum ccp_aes_mode mode;
190 unsigned int version;
191 const char *name;
192 const char *driver_name;
193 unsigned int blocksize;
194 unsigned int ivsize;
195 struct aead_alg *alg_defaults;
196};
197
198static struct ccp_aes_aead_def aes_aead_algs[] = {
199 {
200 .mode = CCP_AES_MODE_GHASH,
201 .version = CCP_VERSION(5, 0),
202 .name = "gcm(aes)",
203 .driver_name = "gcm-aes-ccp",
204 .blocksize = 1,
205 .ivsize = AES_BLOCK_SIZE,
206 .alg_defaults = &ccp_aes_gcm_defaults,
207 },
208};
209
210static int ccp_register_aes_aead(struct list_head *head,
211 const struct ccp_aes_aead_def *def)
212{
213 struct ccp_crypto_aead *ccp_aead;
214 struct aead_alg *alg;
215 int ret;
216
217 ccp_aead = kzalloc(sizeof(*ccp_aead), GFP_KERNEL);
218 if (!ccp_aead)
219 return -ENOMEM;
220
221 INIT_LIST_HEAD(&ccp_aead->entry);
222
223 ccp_aead->mode = def->mode;
224
225 /* Copy the defaults and override as necessary */
226 alg = &ccp_aead->alg;
227 *alg = *def->alg_defaults;
228 snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
229 snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
230 def->driver_name);
231 alg->base.cra_blocksize = def->blocksize;
232 alg->base.cra_ablkcipher.ivsize = def->ivsize;
233
234 ret = crypto_register_aead(alg);
235 if (ret) {
236 pr_err("%s ablkcipher algorithm registration error (%d)\n",
237 alg->base.cra_name, ret);
238 kfree(ccp_aead);
239 return ret;
240 }
241
242 list_add(&ccp_aead->entry, head);
243
244 return 0;
245}
246
247int ccp_register_aes_aeads(struct list_head *head)
248{
249 int i, ret;
250 unsigned int ccpversion = ccp_version();
251
252 for (i = 0; i < ARRAY_SIZE(aes_aead_algs); i++) {
253 if (aes_aead_algs[i].version > ccpversion)
254 continue;
255 ret = ccp_register_aes_aead(head, &aes_aead_algs[i]);
256 if (ret)
257 return ret;
258 }
259
260 return 0;
261}