1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Public Key Encryption
4 *
5 * Copyright (c) 2015, Intel Corporation
6 * Authors: Tadeusz Struk <tadeusz.struk@intel.com>
7 */
8 #include <crypto/internal/akcipher.h>
9 #include <linux/cryptouser.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/scatterlist.h>
14 #include <linux/seq_file.h>
15 #include <linux/slab.h>
16 #include <linux/string.h>
17 #include <net/netlink.h>
18
19 #include "internal.h"
20
21 #define CRYPTO_ALG_TYPE_AHASH_MASK 0x0000000e
22
23 struct crypto_akcipher_sync_data {
24 struct crypto_akcipher *tfm;
25 const void *src;
26 void *dst;
27 unsigned int slen;
28 unsigned int dlen;
29
30 struct akcipher_request *req;
31 struct crypto_wait cwait;
32 struct scatterlist sg;
33 u8 *buf;
34 };
35
crypto_akcipher_report(struct sk_buff * skb,struct crypto_alg * alg)36 static int __maybe_unused crypto_akcipher_report(
37 struct sk_buff *skb, struct crypto_alg *alg)
38 {
39 struct crypto_report_akcipher rakcipher;
40
41 memset(&rakcipher, 0, sizeof(rakcipher));
42
43 strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
44
45 return nla_put(skb, CRYPTOCFGA_REPORT_AKCIPHER,
46 sizeof(rakcipher), &rakcipher);
47 }
48
49 static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
50 __maybe_unused;
51
crypto_akcipher_show(struct seq_file * m,struct crypto_alg * alg)52 static void crypto_akcipher_show(struct seq_file *m, struct crypto_alg *alg)
53 {
54 seq_puts(m, "type : akcipher\n");
55 }
56
crypto_akcipher_exit_tfm(struct crypto_tfm * tfm)57 static void crypto_akcipher_exit_tfm(struct crypto_tfm *tfm)
58 {
59 struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
60 struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
61
62 alg->exit(akcipher);
63 }
64
crypto_akcipher_init_tfm(struct crypto_tfm * tfm)65 static int crypto_akcipher_init_tfm(struct crypto_tfm *tfm)
66 {
67 struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
68 struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
69
70 if (alg->exit)
71 akcipher->base.exit = crypto_akcipher_exit_tfm;
72
73 if (alg->init)
74 return alg->init(akcipher);
75
76 return 0;
77 }
78
crypto_akcipher_free_instance(struct crypto_instance * inst)79 static void crypto_akcipher_free_instance(struct crypto_instance *inst)
80 {
81 struct akcipher_instance *akcipher = akcipher_instance(inst);
82
83 akcipher->free(akcipher);
84 }
85
86 static const struct crypto_type crypto_akcipher_type = {
87 .extsize = crypto_alg_extsize,
88 .init_tfm = crypto_akcipher_init_tfm,
89 .free = crypto_akcipher_free_instance,
90 #ifdef CONFIG_PROC_FS
91 .show = crypto_akcipher_show,
92 #endif
93 #if IS_ENABLED(CONFIG_CRYPTO_USER)
94 .report = crypto_akcipher_report,
95 #endif
96 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
97 .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
98 .type = CRYPTO_ALG_TYPE_AKCIPHER,
99 .tfmsize = offsetof(struct crypto_akcipher, base),
100 .algsize = offsetof(struct akcipher_alg, base),
101 };
102
crypto_grab_akcipher(struct crypto_akcipher_spawn * spawn,struct crypto_instance * inst,const char * name,u32 type,u32 mask)103 int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn,
104 struct crypto_instance *inst,
105 const char *name, u32 type, u32 mask)
106 {
107 spawn->base.frontend = &crypto_akcipher_type;
108 return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
109 }
110 EXPORT_SYMBOL_GPL(crypto_grab_akcipher);
111
crypto_alloc_akcipher(const char * alg_name,u32 type,u32 mask)112 struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
113 u32 mask)
114 {
115 return crypto_alloc_tfm(alg_name, &crypto_akcipher_type, type, mask);
116 }
117 EXPORT_SYMBOL_GPL(crypto_alloc_akcipher);
118
akcipher_prepare_alg(struct akcipher_alg * alg)119 static void akcipher_prepare_alg(struct akcipher_alg *alg)
120 {
121 struct crypto_alg *base = &alg->base;
122
123 base->cra_type = &crypto_akcipher_type;
124 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
125 base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER;
126 }
127
akcipher_default_op(struct akcipher_request * req)128 static int akcipher_default_op(struct akcipher_request *req)
129 {
130 return -ENOSYS;
131 }
132
akcipher_default_set_key(struct crypto_akcipher * tfm,const void * key,unsigned int keylen)133 static int akcipher_default_set_key(struct crypto_akcipher *tfm,
134 const void *key, unsigned int keylen)
135 {
136 return -ENOSYS;
137 }
138
crypto_register_akcipher(struct akcipher_alg * alg)139 int crypto_register_akcipher(struct akcipher_alg *alg)
140 {
141 struct crypto_alg *base = &alg->base;
142
143 if (!alg->encrypt)
144 alg->encrypt = akcipher_default_op;
145 if (!alg->decrypt)
146 alg->decrypt = akcipher_default_op;
147 if (!alg->set_priv_key)
148 alg->set_priv_key = akcipher_default_set_key;
149
150 akcipher_prepare_alg(alg);
151 return crypto_register_alg(base);
152 }
153 EXPORT_SYMBOL_GPL(crypto_register_akcipher);
154
crypto_unregister_akcipher(struct akcipher_alg * alg)155 void crypto_unregister_akcipher(struct akcipher_alg *alg)
156 {
157 crypto_unregister_alg(&alg->base);
158 }
159 EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);
160
akcipher_register_instance(struct crypto_template * tmpl,struct akcipher_instance * inst)161 int akcipher_register_instance(struct crypto_template *tmpl,
162 struct akcipher_instance *inst)
163 {
164 if (WARN_ON(!inst->free))
165 return -EINVAL;
166 akcipher_prepare_alg(&inst->alg);
167 return crypto_register_instance(tmpl, akcipher_crypto_instance(inst));
168 }
169 EXPORT_SYMBOL_GPL(akcipher_register_instance);
170
crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data * data)171 static int crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data *data)
172 {
173 unsigned int reqsize = crypto_akcipher_reqsize(data->tfm);
174 struct akcipher_request *req;
175 struct scatterlist *sg;
176 unsigned int mlen;
177 unsigned int len;
178 u8 *buf;
179
180 mlen = max(data->slen, data->dlen);
181
182 len = sizeof(*req) + reqsize + mlen;
183 if (len < mlen)
184 return -EOVERFLOW;
185
186 req = kzalloc(len, GFP_KERNEL);
187 if (!req)
188 return -ENOMEM;
189
190 data->req = req;
191 akcipher_request_set_tfm(req, data->tfm);
192
193 buf = (u8 *)(req + 1) + reqsize;
194 data->buf = buf;
195 memcpy(buf, data->src, data->slen);
196
197 sg = &data->sg;
198 sg_init_one(sg, buf, mlen);
199 akcipher_request_set_crypt(req, sg, sg, data->slen, data->dlen);
200
201 crypto_init_wait(&data->cwait);
202 akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
203 crypto_req_done, &data->cwait);
204
205 return 0;
206 }
207
crypto_akcipher_sync_post(struct crypto_akcipher_sync_data * data,int err)208 static int crypto_akcipher_sync_post(struct crypto_akcipher_sync_data *data,
209 int err)
210 {
211 err = crypto_wait_req(err, &data->cwait);
212 memcpy(data->dst, data->buf, data->dlen);
213 data->dlen = data->req->dst_len;
214 kfree_sensitive(data->req);
215 return err;
216 }
217
crypto_akcipher_sync_encrypt(struct crypto_akcipher * tfm,const void * src,unsigned int slen,void * dst,unsigned int dlen)218 int crypto_akcipher_sync_encrypt(struct crypto_akcipher *tfm,
219 const void *src, unsigned int slen,
220 void *dst, unsigned int dlen)
221 {
222 struct crypto_akcipher_sync_data data = {
223 .tfm = tfm,
224 .src = src,
225 .dst = dst,
226 .slen = slen,
227 .dlen = dlen,
228 };
229
230 return crypto_akcipher_sync_prep(&data) ?:
231 crypto_akcipher_sync_post(&data,
232 crypto_akcipher_encrypt(data.req));
233 }
234 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_encrypt);
235
crypto_akcipher_sync_decrypt(struct crypto_akcipher * tfm,const void * src,unsigned int slen,void * dst,unsigned int dlen)236 int crypto_akcipher_sync_decrypt(struct crypto_akcipher *tfm,
237 const void *src, unsigned int slen,
238 void *dst, unsigned int dlen)
239 {
240 struct crypto_akcipher_sync_data data = {
241 .tfm = tfm,
242 .src = src,
243 .dst = dst,
244 .slen = slen,
245 .dlen = dlen,
246 };
247
248 return crypto_akcipher_sync_prep(&data) ?:
249 crypto_akcipher_sync_post(&data,
250 crypto_akcipher_decrypt(data.req)) ?:
251 data.dlen;
252 }
253 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_decrypt);
254
255 MODULE_LICENSE("GPL");
256 MODULE_DESCRIPTION("Generic public key cipher type");
257