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 <crypto/internal/des.h>
11 #include <crypto/internal/skcipher.h>
12 #include <linux/err.h>
13 #include <linux/kernel.h>
14 #include <linux/list.h>
15 #include <linux/module.h>
16 #include <linux/scatterlist.h>
17 #include <linux/slab.h>
18 #include <linux/string.h>
19 
20 #include "ccp-crypto.h"
21 
22 static int ccp_des3_complete(struct crypto_async_request *async_req, int ret)
23 {
24 	struct skcipher_request *req = skcipher_request_cast(async_req);
25 	struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(
26 		crypto_skcipher_reqtfm(req));
27 	struct ccp_des3_req_ctx *rctx = skcipher_request_ctx_dma(req);
28 
29 	if (ret)
30 		return ret;
31 
32 	if (ctx->u.des3.mode != CCP_DES3_MODE_ECB)
33 		memcpy(req->iv, rctx->iv, DES3_EDE_BLOCK_SIZE);
34 
35 	return 0;
36 }
37 
38 static int ccp_des3_setkey(struct crypto_skcipher *tfm, const u8 *key,
39 		unsigned int key_len)
40 {
41 	struct ccp_crypto_skcipher_alg *alg = ccp_crypto_skcipher_alg(tfm);
42 	struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
43 	int err;
44 
45 	err = verify_skcipher_des3_key(tfm, key);
46 	if (err)
47 		return err;
48 
49 	/* It's not clear that there is any support for a keysize of 112.
50 	 * If needed, the caller should make K1 == K3
51 	 */
52 	ctx->u.des3.type = CCP_DES3_TYPE_168;
53 	ctx->u.des3.mode = alg->mode;
54 	ctx->u.des3.key_len = key_len;
55 
56 	memcpy(ctx->u.des3.key, key, key_len);
57 	sg_init_one(&ctx->u.des3.key_sg, ctx->u.des3.key, key_len);
58 
59 	return 0;
60 }
61 
62 static int ccp_des3_crypt(struct skcipher_request *req, bool encrypt)
63 {
64 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
65 	struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
66 	struct ccp_des3_req_ctx *rctx = skcipher_request_ctx_dma(req);
67 	struct scatterlist *iv_sg = NULL;
68 	unsigned int iv_len = 0;
69 
70 	if (!ctx->u.des3.key_len)
71 		return -EINVAL;
72 
73 	if (((ctx->u.des3.mode == CCP_DES3_MODE_ECB) ||
74 	     (ctx->u.des3.mode == CCP_DES3_MODE_CBC)) &&
75 	    (req->cryptlen & (DES3_EDE_BLOCK_SIZE - 1)))
76 		return -EINVAL;
77 
78 	if (ctx->u.des3.mode != CCP_DES3_MODE_ECB) {
79 		if (!req->iv)
80 			return -EINVAL;
81 
82 		memcpy(rctx->iv, req->iv, DES3_EDE_BLOCK_SIZE);
83 		iv_sg = &rctx->iv_sg;
84 		iv_len = DES3_EDE_BLOCK_SIZE;
85 		sg_init_one(iv_sg, rctx->iv, iv_len);
86 	}
87 
88 	memset(&rctx->cmd, 0, sizeof(rctx->cmd));
89 	INIT_LIST_HEAD(&rctx->cmd.entry);
90 	rctx->cmd.engine = CCP_ENGINE_DES3;
91 	rctx->cmd.u.des3.type = ctx->u.des3.type;
92 	rctx->cmd.u.des3.mode = ctx->u.des3.mode;
93 	rctx->cmd.u.des3.action = (encrypt)
94 				  ? CCP_DES3_ACTION_ENCRYPT
95 				  : CCP_DES3_ACTION_DECRYPT;
96 	rctx->cmd.u.des3.key = &ctx->u.des3.key_sg;
97 	rctx->cmd.u.des3.key_len = ctx->u.des3.key_len;
98 	rctx->cmd.u.des3.iv = iv_sg;
99 	rctx->cmd.u.des3.iv_len = iv_len;
100 	rctx->cmd.u.des3.src = req->src;
101 	rctx->cmd.u.des3.src_len = req->cryptlen;
102 	rctx->cmd.u.des3.dst = req->dst;
103 
104 	return ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
105 }
106 
107 static int ccp_des3_encrypt(struct skcipher_request *req)
108 {
109 	return ccp_des3_crypt(req, true);
110 }
111 
112 static int ccp_des3_decrypt(struct skcipher_request *req)
113 {
114 	return ccp_des3_crypt(req, false);
115 }
116 
117 static int ccp_des3_init_tfm(struct crypto_skcipher *tfm)
118 {
119 	struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
120 
121 	ctx->complete = ccp_des3_complete;
122 	ctx->u.des3.key_len = 0;
123 
124 	crypto_skcipher_set_reqsize_dma(tfm, sizeof(struct ccp_des3_req_ctx));
125 
126 	return 0;
127 }
128 
129 static const struct skcipher_alg ccp_des3_defaults = {
130 	.setkey			= ccp_des3_setkey,
131 	.encrypt		= ccp_des3_encrypt,
132 	.decrypt		= ccp_des3_decrypt,
133 	.min_keysize		= DES3_EDE_KEY_SIZE,
134 	.max_keysize		= DES3_EDE_KEY_SIZE,
135 	.init			= ccp_des3_init_tfm,
136 
137 	.base.cra_flags		= CRYPTO_ALG_ASYNC |
138 				  CRYPTO_ALG_ALLOCATES_MEMORY |
139 				  CRYPTO_ALG_KERN_DRIVER_ONLY |
140 				  CRYPTO_ALG_NEED_FALLBACK,
141 	.base.cra_blocksize	= DES3_EDE_BLOCK_SIZE,
142 	.base.cra_ctxsize	= sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,
143 	.base.cra_priority	= CCP_CRA_PRIORITY,
144 	.base.cra_module	= THIS_MODULE,
145 };
146 
147 struct ccp_des3_def {
148 	enum ccp_des3_mode mode;
149 	unsigned int version;
150 	const char *name;
151 	const char *driver_name;
152 	unsigned int blocksize;
153 	unsigned int ivsize;
154 	const struct skcipher_alg *alg_defaults;
155 };
156 
157 static const struct ccp_des3_def des3_algs[] = {
158 	{
159 		.mode		= CCP_DES3_MODE_ECB,
160 		.version	= CCP_VERSION(5, 0),
161 		.name		= "ecb(des3_ede)",
162 		.driver_name	= "ecb-des3-ccp",
163 		.blocksize	= DES3_EDE_BLOCK_SIZE,
164 		.ivsize		= 0,
165 		.alg_defaults	= &ccp_des3_defaults,
166 	},
167 	{
168 		.mode		= CCP_DES3_MODE_CBC,
169 		.version	= CCP_VERSION(5, 0),
170 		.name		= "cbc(des3_ede)",
171 		.driver_name	= "cbc-des3-ccp",
172 		.blocksize	= DES3_EDE_BLOCK_SIZE,
173 		.ivsize		= DES3_EDE_BLOCK_SIZE,
174 		.alg_defaults	= &ccp_des3_defaults,
175 	},
176 };
177 
178 static int ccp_register_des3_alg(struct list_head *head,
179 				 const struct ccp_des3_def *def)
180 {
181 	struct ccp_crypto_skcipher_alg *ccp_alg;
182 	struct skcipher_alg *alg;
183 	int ret;
184 
185 	ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
186 	if (!ccp_alg)
187 		return -ENOMEM;
188 
189 	INIT_LIST_HEAD(&ccp_alg->entry);
190 
191 	ccp_alg->mode = def->mode;
192 
193 	/* Copy the defaults and override as necessary */
194 	alg = &ccp_alg->alg;
195 	*alg = *def->alg_defaults;
196 	snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
197 	snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
198 			def->driver_name);
199 	alg->base.cra_blocksize = def->blocksize;
200 	alg->ivsize = def->ivsize;
201 
202 	ret = crypto_register_skcipher(alg);
203 	if (ret) {
204 		pr_err("%s skcipher algorithm registration error (%d)\n",
205 				alg->base.cra_name, ret);
206 		kfree(ccp_alg);
207 		return ret;
208 	}
209 
210 	list_add(&ccp_alg->entry, head);
211 
212 	return 0;
213 }
214 
215 int ccp_register_des3_algs(struct list_head *head)
216 {
217 	int i, ret;
218 	unsigned int ccpversion = ccp_version();
219 
220 	for (i = 0; i < ARRAY_SIZE(des3_algs); i++) {
221 		if (des3_algs[i].version > ccpversion)
222 			continue;
223 		ret = ccp_register_des3_alg(head, &des3_algs[i]);
224 		if (ret)
225 			return ret;
226 	}
227 
228 	return 0;
229 }
230