1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AMD Cryptographic Coprocessor (CCP) DES3 crypto API support
4  *
5  * Copyright (C) 2016,2017 Advanced Micro Devices, Inc.
6  *
7  * Author: Gary R Hook <ghook@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/scatterwalk.h>
17 #include <crypto/internal/des.h>
18 
19 #include "ccp-crypto.h"
20 
21 static int ccp_des3_complete(struct crypto_async_request *async_req, int ret)
22 {
23 	struct skcipher_request *req = skcipher_request_cast(async_req);
24 	struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(
25 		crypto_skcipher_reqtfm(req));
26 	struct ccp_des3_req_ctx *rctx = skcipher_request_ctx_dma(req);
27 
28 	if (ret)
29 		return ret;
30 
31 	if (ctx->u.des3.mode != CCP_DES3_MODE_ECB)
32 		memcpy(req->iv, rctx->iv, DES3_EDE_BLOCK_SIZE);
33 
34 	return 0;
35 }
36 
37 static int ccp_des3_setkey(struct crypto_skcipher *tfm, const u8 *key,
38 		unsigned int key_len)
39 {
40 	struct ccp_crypto_skcipher_alg *alg = ccp_crypto_skcipher_alg(tfm);
41 	struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
42 	int err;
43 
44 	err = verify_skcipher_des3_key(tfm, key);
45 	if (err)
46 		return err;
47 
48 	/* It's not clear that there is any support for a keysize of 112.
49 	 * If needed, the caller should make K1 == K3
50 	 */
51 	ctx->u.des3.type = CCP_DES3_TYPE_168;
52 	ctx->u.des3.mode = alg->mode;
53 	ctx->u.des3.key_len = key_len;
54 
55 	memcpy(ctx->u.des3.key, key, key_len);
56 	sg_init_one(&ctx->u.des3.key_sg, ctx->u.des3.key, key_len);
57 
58 	return 0;
59 }
60 
61 static int ccp_des3_crypt(struct skcipher_request *req, bool encrypt)
62 {
63 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
64 	struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
65 	struct ccp_des3_req_ctx *rctx = skcipher_request_ctx_dma(req);
66 	struct scatterlist *iv_sg = NULL;
67 	unsigned int iv_len = 0;
68 
69 	if (!ctx->u.des3.key_len)
70 		return -EINVAL;
71 
72 	if (((ctx->u.des3.mode == CCP_DES3_MODE_ECB) ||
73 	     (ctx->u.des3.mode == CCP_DES3_MODE_CBC)) &&
74 	    (req->cryptlen & (DES3_EDE_BLOCK_SIZE - 1)))
75 		return -EINVAL;
76 
77 	if (ctx->u.des3.mode != CCP_DES3_MODE_ECB) {
78 		if (!req->iv)
79 			return -EINVAL;
80 
81 		memcpy(rctx->iv, req->iv, DES3_EDE_BLOCK_SIZE);
82 		iv_sg = &rctx->iv_sg;
83 		iv_len = DES3_EDE_BLOCK_SIZE;
84 		sg_init_one(iv_sg, rctx->iv, iv_len);
85 	}
86 
87 	memset(&rctx->cmd, 0, sizeof(rctx->cmd));
88 	INIT_LIST_HEAD(&rctx->cmd.entry);
89 	rctx->cmd.engine = CCP_ENGINE_DES3;
90 	rctx->cmd.u.des3.type = ctx->u.des3.type;
91 	rctx->cmd.u.des3.mode = ctx->u.des3.mode;
92 	rctx->cmd.u.des3.action = (encrypt)
93 				  ? CCP_DES3_ACTION_ENCRYPT
94 				  : CCP_DES3_ACTION_DECRYPT;
95 	rctx->cmd.u.des3.key = &ctx->u.des3.key_sg;
96 	rctx->cmd.u.des3.key_len = ctx->u.des3.key_len;
97 	rctx->cmd.u.des3.iv = iv_sg;
98 	rctx->cmd.u.des3.iv_len = iv_len;
99 	rctx->cmd.u.des3.src = req->src;
100 	rctx->cmd.u.des3.src_len = req->cryptlen;
101 	rctx->cmd.u.des3.dst = req->dst;
102 
103 	return ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
104 }
105 
106 static int ccp_des3_encrypt(struct skcipher_request *req)
107 {
108 	return ccp_des3_crypt(req, true);
109 }
110 
111 static int ccp_des3_decrypt(struct skcipher_request *req)
112 {
113 	return ccp_des3_crypt(req, false);
114 }
115 
116 static int ccp_des3_init_tfm(struct crypto_skcipher *tfm)
117 {
118 	struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
119 
120 	ctx->complete = ccp_des3_complete;
121 	ctx->u.des3.key_len = 0;
122 
123 	crypto_skcipher_set_reqsize_dma(tfm, sizeof(struct ccp_des3_req_ctx));
124 
125 	return 0;
126 }
127 
128 static const struct skcipher_alg ccp_des3_defaults = {
129 	.setkey			= ccp_des3_setkey,
130 	.encrypt		= ccp_des3_encrypt,
131 	.decrypt		= ccp_des3_decrypt,
132 	.min_keysize		= DES3_EDE_KEY_SIZE,
133 	.max_keysize		= DES3_EDE_KEY_SIZE,
134 	.init			= ccp_des3_init_tfm,
135 
136 	.base.cra_flags		= CRYPTO_ALG_ASYNC |
137 				  CRYPTO_ALG_ALLOCATES_MEMORY |
138 				  CRYPTO_ALG_KERN_DRIVER_ONLY |
139 				  CRYPTO_ALG_NEED_FALLBACK,
140 	.base.cra_blocksize	= DES3_EDE_BLOCK_SIZE,
141 	.base.cra_ctxsize	= sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,
142 	.base.cra_priority	= CCP_CRA_PRIORITY,
143 	.base.cra_module	= THIS_MODULE,
144 };
145 
146 struct ccp_des3_def {
147 	enum ccp_des3_mode mode;
148 	unsigned int version;
149 	const char *name;
150 	const char *driver_name;
151 	unsigned int blocksize;
152 	unsigned int ivsize;
153 	const struct skcipher_alg *alg_defaults;
154 };
155 
156 static const struct ccp_des3_def des3_algs[] = {
157 	{
158 		.mode		= CCP_DES3_MODE_ECB,
159 		.version	= CCP_VERSION(5, 0),
160 		.name		= "ecb(des3_ede)",
161 		.driver_name	= "ecb-des3-ccp",
162 		.blocksize	= DES3_EDE_BLOCK_SIZE,
163 		.ivsize		= 0,
164 		.alg_defaults	= &ccp_des3_defaults,
165 	},
166 	{
167 		.mode		= CCP_DES3_MODE_CBC,
168 		.version	= CCP_VERSION(5, 0),
169 		.name		= "cbc(des3_ede)",
170 		.driver_name	= "cbc-des3-ccp",
171 		.blocksize	= DES3_EDE_BLOCK_SIZE,
172 		.ivsize		= DES3_EDE_BLOCK_SIZE,
173 		.alg_defaults	= &ccp_des3_defaults,
174 	},
175 };
176 
177 static int ccp_register_des3_alg(struct list_head *head,
178 				 const struct ccp_des3_def *def)
179 {
180 	struct ccp_crypto_skcipher_alg *ccp_alg;
181 	struct skcipher_alg *alg;
182 	int ret;
183 
184 	ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
185 	if (!ccp_alg)
186 		return -ENOMEM;
187 
188 	INIT_LIST_HEAD(&ccp_alg->entry);
189 
190 	ccp_alg->mode = def->mode;
191 
192 	/* Copy the defaults and override as necessary */
193 	alg = &ccp_alg->alg;
194 	*alg = *def->alg_defaults;
195 	snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
196 	snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
197 			def->driver_name);
198 	alg->base.cra_blocksize = def->blocksize;
199 	alg->ivsize = def->ivsize;
200 
201 	ret = crypto_register_skcipher(alg);
202 	if (ret) {
203 		pr_err("%s skcipher algorithm registration error (%d)\n",
204 				alg->base.cra_name, ret);
205 		kfree(ccp_alg);
206 		return ret;
207 	}
208 
209 	list_add(&ccp_alg->entry, head);
210 
211 	return 0;
212 }
213 
214 int ccp_register_des3_algs(struct list_head *head)
215 {
216 	int i, ret;
217 	unsigned int ccpversion = ccp_version();
218 
219 	for (i = 0; i < ARRAY_SIZE(des3_algs); i++) {
220 		if (des3_algs[i].version > ccpversion)
221 			continue;
222 		ret = ccp_register_des3_alg(head, &des3_algs[i]);
223 		if (ret)
224 			return ret;
225 	}
226 
227 	return 0;
228 }
229