This source file includes following definitions.
- public_key_describe
- public_key_free
- public_key_destroy
- software_key_determine_akcipher
- pkey_pack_u32
- software_key_query
- software_key_eds_op
- public_key_verify_signature
- public_key_verify_signature_2
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10 #define pr_fmt(fmt) "PKEY: "fmt
11 #include <linux/module.h>
12 #include <linux/export.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/seq_file.h>
16 #include <linux/scatterlist.h>
17 #include <keys/asymmetric-subtype.h>
18 #include <crypto/public_key.h>
19 #include <crypto/akcipher.h>
20
21 MODULE_DESCRIPTION("In-software asymmetric public-key subtype");
22 MODULE_AUTHOR("Red Hat, Inc.");
23 MODULE_LICENSE("GPL");
24
25
26
27
28 static void public_key_describe(const struct key *asymmetric_key,
29 struct seq_file *m)
30 {
31 struct public_key *key = asymmetric_key->payload.data[asym_crypto];
32
33 if (key)
34 seq_printf(m, "%s.%s", key->id_type, key->pkey_algo);
35 }
36
37
38
39
40 void public_key_free(struct public_key *key)
41 {
42 if (key) {
43 kfree(key->key);
44 kfree(key->params);
45 kfree(key);
46 }
47 }
48 EXPORT_SYMBOL_GPL(public_key_free);
49
50
51
52
53 static void public_key_destroy(void *payload0, void *payload3)
54 {
55 public_key_free(payload0);
56 public_key_signature_free(payload3);
57 }
58
59
60
61
62 static
63 int software_key_determine_akcipher(const char *encoding,
64 const char *hash_algo,
65 const struct public_key *pkey,
66 char alg_name[CRYPTO_MAX_ALG_NAME])
67 {
68 int n;
69
70 if (strcmp(encoding, "pkcs1") == 0) {
71
72
73
74
75 if (!hash_algo)
76 n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
77 "pkcs1pad(%s)",
78 pkey->pkey_algo);
79 else
80 n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
81 "pkcs1pad(%s,%s)",
82 pkey->pkey_algo, hash_algo);
83 return n >= CRYPTO_MAX_ALG_NAME ? -EINVAL : 0;
84 }
85
86 if (strcmp(encoding, "raw") == 0) {
87 strcpy(alg_name, pkey->pkey_algo);
88 return 0;
89 }
90
91 return -ENOPKG;
92 }
93
94 static u8 *pkey_pack_u32(u8 *dst, u32 val)
95 {
96 memcpy(dst, &val, sizeof(val));
97 return dst + sizeof(val);
98 }
99
100
101
102
103 static int software_key_query(const struct kernel_pkey_params *params,
104 struct kernel_pkey_query *info)
105 {
106 struct crypto_akcipher *tfm;
107 struct public_key *pkey = params->key->payload.data[asym_crypto];
108 char alg_name[CRYPTO_MAX_ALG_NAME];
109 u8 *key, *ptr;
110 int ret, len;
111
112 ret = software_key_determine_akcipher(params->encoding,
113 params->hash_algo,
114 pkey, alg_name);
115 if (ret < 0)
116 return ret;
117
118 tfm = crypto_alloc_akcipher(alg_name, 0, 0);
119 if (IS_ERR(tfm))
120 return PTR_ERR(tfm);
121
122 key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
123 GFP_KERNEL);
124 if (!key)
125 goto error_free_tfm;
126 memcpy(key, pkey->key, pkey->keylen);
127 ptr = key + pkey->keylen;
128 ptr = pkey_pack_u32(ptr, pkey->algo);
129 ptr = pkey_pack_u32(ptr, pkey->paramlen);
130 memcpy(ptr, pkey->params, pkey->paramlen);
131
132 if (pkey->key_is_private)
133 ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
134 else
135 ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
136 if (ret < 0)
137 goto error_free_key;
138
139 len = crypto_akcipher_maxsize(tfm);
140 info->key_size = len * 8;
141 info->max_data_size = len;
142 info->max_sig_size = len;
143 info->max_enc_size = len;
144 info->max_dec_size = len;
145 info->supported_ops = (KEYCTL_SUPPORTS_ENCRYPT |
146 KEYCTL_SUPPORTS_VERIFY);
147 if (pkey->key_is_private)
148 info->supported_ops |= (KEYCTL_SUPPORTS_DECRYPT |
149 KEYCTL_SUPPORTS_SIGN);
150 ret = 0;
151
152 error_free_key:
153 kfree(key);
154 error_free_tfm:
155 crypto_free_akcipher(tfm);
156 pr_devel("<==%s() = %d\n", __func__, ret);
157 return ret;
158 }
159
160
161
162
163 static int software_key_eds_op(struct kernel_pkey_params *params,
164 const void *in, void *out)
165 {
166 const struct public_key *pkey = params->key->payload.data[asym_crypto];
167 struct akcipher_request *req;
168 struct crypto_akcipher *tfm;
169 struct crypto_wait cwait;
170 struct scatterlist in_sg, out_sg;
171 char alg_name[CRYPTO_MAX_ALG_NAME];
172 char *key, *ptr;
173 int ret;
174
175 pr_devel("==>%s()\n", __func__);
176
177 ret = software_key_determine_akcipher(params->encoding,
178 params->hash_algo,
179 pkey, alg_name);
180 if (ret < 0)
181 return ret;
182
183 tfm = crypto_alloc_akcipher(alg_name, 0, 0);
184 if (IS_ERR(tfm))
185 return PTR_ERR(tfm);
186
187 ret = -ENOMEM;
188 req = akcipher_request_alloc(tfm, GFP_KERNEL);
189 if (!req)
190 goto error_free_tfm;
191
192 key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
193 GFP_KERNEL);
194 if (!key)
195 goto error_free_req;
196
197 memcpy(key, pkey->key, pkey->keylen);
198 ptr = key + pkey->keylen;
199 ptr = pkey_pack_u32(ptr, pkey->algo);
200 ptr = pkey_pack_u32(ptr, pkey->paramlen);
201 memcpy(ptr, pkey->params, pkey->paramlen);
202
203 if (pkey->key_is_private)
204 ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
205 else
206 ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
207 if (ret)
208 goto error_free_key;
209
210 sg_init_one(&in_sg, in, params->in_len);
211 sg_init_one(&out_sg, out, params->out_len);
212 akcipher_request_set_crypt(req, &in_sg, &out_sg, params->in_len,
213 params->out_len);
214 crypto_init_wait(&cwait);
215 akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
216 CRYPTO_TFM_REQ_MAY_SLEEP,
217 crypto_req_done, &cwait);
218
219
220 switch (params->op) {
221 case kernel_pkey_encrypt:
222 ret = crypto_akcipher_encrypt(req);
223 break;
224 case kernel_pkey_decrypt:
225 ret = crypto_akcipher_decrypt(req);
226 break;
227 case kernel_pkey_sign:
228 ret = crypto_akcipher_sign(req);
229 break;
230 default:
231 BUG();
232 }
233
234 ret = crypto_wait_req(ret, &cwait);
235 if (ret == 0)
236 ret = req->dst_len;
237
238 error_free_key:
239 kfree(key);
240 error_free_req:
241 akcipher_request_free(req);
242 error_free_tfm:
243 crypto_free_akcipher(tfm);
244 pr_devel("<==%s() = %d\n", __func__, ret);
245 return ret;
246 }
247
248
249
250
251 int public_key_verify_signature(const struct public_key *pkey,
252 const struct public_key_signature *sig)
253 {
254 struct crypto_wait cwait;
255 struct crypto_akcipher *tfm;
256 struct akcipher_request *req;
257 struct scatterlist src_sg[2];
258 char alg_name[CRYPTO_MAX_ALG_NAME];
259 char *key, *ptr;
260 int ret;
261
262 pr_devel("==>%s()\n", __func__);
263
264 BUG_ON(!pkey);
265 BUG_ON(!sig);
266 BUG_ON(!sig->s);
267
268 ret = software_key_determine_akcipher(sig->encoding,
269 sig->hash_algo,
270 pkey, alg_name);
271 if (ret < 0)
272 return ret;
273
274 tfm = crypto_alloc_akcipher(alg_name, 0, 0);
275 if (IS_ERR(tfm))
276 return PTR_ERR(tfm);
277
278 ret = -ENOMEM;
279 req = akcipher_request_alloc(tfm, GFP_KERNEL);
280 if (!req)
281 goto error_free_tfm;
282
283 key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
284 GFP_KERNEL);
285 if (!key)
286 goto error_free_req;
287
288 memcpy(key, pkey->key, pkey->keylen);
289 ptr = key + pkey->keylen;
290 ptr = pkey_pack_u32(ptr, pkey->algo);
291 ptr = pkey_pack_u32(ptr, pkey->paramlen);
292 memcpy(ptr, pkey->params, pkey->paramlen);
293
294 if (pkey->key_is_private)
295 ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
296 else
297 ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
298 if (ret)
299 goto error_free_key;
300
301 sg_init_table(src_sg, 2);
302 sg_set_buf(&src_sg[0], sig->s, sig->s_size);
303 sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
304 akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size,
305 sig->digest_size);
306 crypto_init_wait(&cwait);
307 akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
308 CRYPTO_TFM_REQ_MAY_SLEEP,
309 crypto_req_done, &cwait);
310 ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
311
312 error_free_key:
313 kfree(key);
314 error_free_req:
315 akcipher_request_free(req);
316 error_free_tfm:
317 crypto_free_akcipher(tfm);
318 pr_devel("<==%s() = %d\n", __func__, ret);
319 if (WARN_ON_ONCE(ret > 0))
320 ret = -EINVAL;
321 return ret;
322 }
323 EXPORT_SYMBOL_GPL(public_key_verify_signature);
324
325 static int public_key_verify_signature_2(const struct key *key,
326 const struct public_key_signature *sig)
327 {
328 const struct public_key *pk = key->payload.data[asym_crypto];
329 return public_key_verify_signature(pk, sig);
330 }
331
332
333
334
335 struct asymmetric_key_subtype public_key_subtype = {
336 .owner = THIS_MODULE,
337 .name = "public_key",
338 .name_len = sizeof("public_key") - 1,
339 .describe = public_key_describe,
340 .destroy = public_key_destroy,
341 .query = software_key_query,
342 .eds_op = software_key_eds_op,
343 .verify_signature = public_key_verify_signature_2,
344 };
345 EXPORT_SYMBOL_GPL(public_key_subtype);