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
crypto_akcipher_show(struct seq_file * m,struct crypto_alg * alg)49 static void __maybe_unused crypto_akcipher_show(struct seq_file *m,
50 struct crypto_alg *alg)
51 {
52 seq_puts(m, "type : akcipher\n");
53 }
54
crypto_akcipher_exit_tfm(struct crypto_tfm * tfm)55 static void crypto_akcipher_exit_tfm(struct crypto_tfm *tfm)
56 {
57 struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
58 struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
59
60 alg->exit(akcipher);
61 }
62
crypto_akcipher_init_tfm(struct crypto_tfm * tfm)63 static int crypto_akcipher_init_tfm(struct crypto_tfm *tfm)
64 {
65 struct crypto_akcipher *akcipher = __crypto_akcipher_tfm(tfm);
66 struct akcipher_alg *alg = crypto_akcipher_alg(akcipher);
67
68 if (alg->exit)
69 akcipher->base.exit = crypto_akcipher_exit_tfm;
70
71 if (alg->init)
72 return alg->init(akcipher);
73
74 return 0;
75 }
76
crypto_akcipher_free_instance(struct crypto_instance * inst)77 static void crypto_akcipher_free_instance(struct crypto_instance *inst)
78 {
79 struct akcipher_instance *akcipher = akcipher_instance(inst);
80
81 akcipher->free(akcipher);
82 }
83
84 static const struct crypto_type crypto_akcipher_type = {
85 .extsize = crypto_alg_extsize,
86 .init_tfm = crypto_akcipher_init_tfm,
87 .free = crypto_akcipher_free_instance,
88 #ifdef CONFIG_PROC_FS
89 .show = crypto_akcipher_show,
90 #endif
91 #if IS_ENABLED(CONFIG_CRYPTO_USER)
92 .report = crypto_akcipher_report,
93 #endif
94 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
95 .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
96 .type = CRYPTO_ALG_TYPE_AKCIPHER,
97 .tfmsize = offsetof(struct crypto_akcipher, base),
98 .algsize = offsetof(struct akcipher_alg, base),
99 };
100
crypto_grab_akcipher(struct crypto_akcipher_spawn * spawn,struct crypto_instance * inst,const char * name,u32 type,u32 mask)101 int crypto_grab_akcipher(struct crypto_akcipher_spawn *spawn,
102 struct crypto_instance *inst,
103 const char *name, u32 type, u32 mask)
104 {
105 spawn->base.frontend = &crypto_akcipher_type;
106 return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
107 }
108 EXPORT_SYMBOL_GPL(crypto_grab_akcipher);
109
crypto_alloc_akcipher(const char * alg_name,u32 type,u32 mask)110 struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type,
111 u32 mask)
112 {
113 return crypto_alloc_tfm(alg_name, &crypto_akcipher_type, type, mask);
114 }
115 EXPORT_SYMBOL_GPL(crypto_alloc_akcipher);
116
akcipher_prepare_alg(struct akcipher_alg * alg)117 static void akcipher_prepare_alg(struct akcipher_alg *alg)
118 {
119 struct crypto_alg *base = &alg->base;
120
121 base->cra_type = &crypto_akcipher_type;
122 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
123 base->cra_flags |= CRYPTO_ALG_TYPE_AKCIPHER;
124 }
125
akcipher_default_op(struct akcipher_request * req)126 static int akcipher_default_op(struct akcipher_request *req)
127 {
128 return -ENOSYS;
129 }
130
akcipher_default_set_key(struct crypto_akcipher * tfm,const void * key,unsigned int keylen)131 static int akcipher_default_set_key(struct crypto_akcipher *tfm,
132 const void *key, unsigned int keylen)
133 {
134 return -ENOSYS;
135 }
136
crypto_register_akcipher(struct akcipher_alg * alg)137 int crypto_register_akcipher(struct akcipher_alg *alg)
138 {
139 struct crypto_alg *base = &alg->base;
140
141 if (!alg->encrypt)
142 alg->encrypt = akcipher_default_op;
143 if (!alg->decrypt)
144 alg->decrypt = akcipher_default_op;
145 if (!alg->set_priv_key)
146 alg->set_priv_key = akcipher_default_set_key;
147
148 akcipher_prepare_alg(alg);
149 return crypto_register_alg(base);
150 }
151 EXPORT_SYMBOL_GPL(crypto_register_akcipher);
152
crypto_unregister_akcipher(struct akcipher_alg * alg)153 void crypto_unregister_akcipher(struct akcipher_alg *alg)
154 {
155 crypto_unregister_alg(&alg->base);
156 }
157 EXPORT_SYMBOL_GPL(crypto_unregister_akcipher);
158
akcipher_register_instance(struct crypto_template * tmpl,struct akcipher_instance * inst)159 int akcipher_register_instance(struct crypto_template *tmpl,
160 struct akcipher_instance *inst)
161 {
162 if (WARN_ON(!inst->free))
163 return -EINVAL;
164 akcipher_prepare_alg(&inst->alg);
165 return crypto_register_instance(tmpl, akcipher_crypto_instance(inst));
166 }
167 EXPORT_SYMBOL_GPL(akcipher_register_instance);
168
crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data * data)169 static int crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data *data)
170 {
171 unsigned int reqsize = crypto_akcipher_reqsize(data->tfm);
172 struct akcipher_request *req;
173 struct scatterlist *sg;
174 unsigned int mlen;
175 unsigned int len;
176 u8 *buf;
177
178 mlen = max(data->slen, data->dlen);
179
180 len = sizeof(*req) + reqsize + mlen;
181 if (len < mlen)
182 return -EOVERFLOW;
183
184 req = kzalloc(len, GFP_KERNEL);
185 if (!req)
186 return -ENOMEM;
187
188 data->req = req;
189 akcipher_request_set_tfm(req, data->tfm);
190
191 buf = (u8 *)(req + 1) + reqsize;
192 data->buf = buf;
193 memcpy(buf, data->src, data->slen);
194
195 sg = &data->sg;
196 sg_init_one(sg, buf, mlen);
197 akcipher_request_set_crypt(req, sg, sg, data->slen, data->dlen);
198
199 crypto_init_wait(&data->cwait);
200 akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
201 crypto_req_done, &data->cwait);
202
203 return 0;
204 }
205
crypto_akcipher_sync_post(struct crypto_akcipher_sync_data * data,int err)206 static int crypto_akcipher_sync_post(struct crypto_akcipher_sync_data *data,
207 int err)
208 {
209 err = crypto_wait_req(err, &data->cwait);
210 memcpy(data->dst, data->buf, data->dlen);
211 data->dlen = data->req->dst_len;
212 kfree_sensitive(data->req);
213 return err;
214 }
215
crypto_akcipher_sync_encrypt(struct crypto_akcipher * tfm,const void * src,unsigned int slen,void * dst,unsigned int dlen)216 int crypto_akcipher_sync_encrypt(struct crypto_akcipher *tfm,
217 const void *src, unsigned int slen,
218 void *dst, unsigned int dlen)
219 {
220 struct crypto_akcipher_sync_data data = {
221 .tfm = tfm,
222 .src = src,
223 .dst = dst,
224 .slen = slen,
225 .dlen = dlen,
226 };
227
228 return crypto_akcipher_sync_prep(&data) ?:
229 crypto_akcipher_sync_post(&data,
230 crypto_akcipher_encrypt(data.req));
231 }
232 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_encrypt);
233
crypto_akcipher_sync_decrypt(struct crypto_akcipher * tfm,const void * src,unsigned int slen,void * dst,unsigned int dlen)234 int crypto_akcipher_sync_decrypt(struct crypto_akcipher *tfm,
235 const void *src, unsigned int slen,
236 void *dst, unsigned int dlen)
237 {
238 struct crypto_akcipher_sync_data data = {
239 .tfm = tfm,
240 .src = src,
241 .dst = dst,
242 .slen = slen,
243 .dlen = dlen,
244 };
245
246 return crypto_akcipher_sync_prep(&data) ?:
247 crypto_akcipher_sync_post(&data,
248 crypto_akcipher_decrypt(data.req)) ?:
249 data.dlen;
250 }
251 EXPORT_SYMBOL_GPL(crypto_akcipher_sync_decrypt);
252
253 MODULE_LICENSE("GPL");
254 MODULE_DESCRIPTION("Generic public key cipher type");
255