Merge tag 'hwmon-for-linus-v4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel...
[sfrench/cifs-2.6.git] / crypto / aead.c
1 /*
2  * AEAD: Authenticated Encryption with Associated Data
3  *
4  * This file provides API support for AEAD algorithms.
5  *
6  * Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License as published by the Free
10  * Software Foundation; either version 2 of the License, or (at your option)
11  * any later version.
12  *
13  */
14
15 #include <crypto/internal/geniv.h>
16 #include <crypto/internal/rng.h>
17 #include <crypto/null.h>
18 #include <crypto/scatterwalk.h>
19 #include <linux/err.h>
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/rtnetlink.h>
24 #include <linux/slab.h>
25 #include <linux/seq_file.h>
26 #include <linux/cryptouser.h>
27 #include <linux/compiler.h>
28 #include <net/netlink.h>
29
30 #include "internal.h"
31
32 static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key,
33                             unsigned int keylen)
34 {
35         unsigned long alignmask = crypto_aead_alignmask(tfm);
36         int ret;
37         u8 *buffer, *alignbuffer;
38         unsigned long absize;
39
40         absize = keylen + alignmask;
41         buffer = kmalloc(absize, GFP_ATOMIC);
42         if (!buffer)
43                 return -ENOMEM;
44
45         alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
46         memcpy(alignbuffer, key, keylen);
47         ret = crypto_aead_alg(tfm)->setkey(tfm, alignbuffer, keylen);
48         memset(alignbuffer, 0, keylen);
49         kfree(buffer);
50         return ret;
51 }
52
53 int crypto_aead_setkey(struct crypto_aead *tfm,
54                        const u8 *key, unsigned int keylen)
55 {
56         unsigned long alignmask = crypto_aead_alignmask(tfm);
57
58         if ((unsigned long)key & alignmask)
59                 return setkey_unaligned(tfm, key, keylen);
60
61         return crypto_aead_alg(tfm)->setkey(tfm, key, keylen);
62 }
63 EXPORT_SYMBOL_GPL(crypto_aead_setkey);
64
65 int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
66 {
67         int err;
68
69         if (authsize > crypto_aead_maxauthsize(tfm))
70                 return -EINVAL;
71
72         if (crypto_aead_alg(tfm)->setauthsize) {
73                 err = crypto_aead_alg(tfm)->setauthsize(tfm, authsize);
74                 if (err)
75                         return err;
76         }
77
78         tfm->authsize = authsize;
79         return 0;
80 }
81 EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);
82
83 static void crypto_aead_exit_tfm(struct crypto_tfm *tfm)
84 {
85         struct crypto_aead *aead = __crypto_aead_cast(tfm);
86         struct aead_alg *alg = crypto_aead_alg(aead);
87
88         alg->exit(aead);
89 }
90
91 static int crypto_aead_init_tfm(struct crypto_tfm *tfm)
92 {
93         struct crypto_aead *aead = __crypto_aead_cast(tfm);
94         struct aead_alg *alg = crypto_aead_alg(aead);
95
96         aead->authsize = alg->maxauthsize;
97
98         if (alg->exit)
99                 aead->base.exit = crypto_aead_exit_tfm;
100
101         if (alg->init)
102                 return alg->init(aead);
103
104         return 0;
105 }
106
107 #ifdef CONFIG_NET
108 static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
109 {
110         struct crypto_report_aead raead;
111         struct aead_alg *aead = container_of(alg, struct aead_alg, base);
112
113         strncpy(raead.type, "aead", sizeof(raead.type));
114         strncpy(raead.geniv, "<none>", sizeof(raead.geniv));
115
116         raead.blocksize = alg->cra_blocksize;
117         raead.maxauthsize = aead->maxauthsize;
118         raead.ivsize = aead->ivsize;
119
120         if (nla_put(skb, CRYPTOCFGA_REPORT_AEAD,
121                     sizeof(struct crypto_report_aead), &raead))
122                 goto nla_put_failure;
123         return 0;
124
125 nla_put_failure:
126         return -EMSGSIZE;
127 }
128 #else
129 static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
130 {
131         return -ENOSYS;
132 }
133 #endif
134
135 static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
136         __maybe_unused;
137 static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
138 {
139         struct aead_alg *aead = container_of(alg, struct aead_alg, base);
140
141         seq_printf(m, "type         : aead\n");
142         seq_printf(m, "async        : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
143                                              "yes" : "no");
144         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
145         seq_printf(m, "ivsize       : %u\n", aead->ivsize);
146         seq_printf(m, "maxauthsize  : %u\n", aead->maxauthsize);
147         seq_printf(m, "geniv        : <none>\n");
148 }
149
150 static void crypto_aead_free_instance(struct crypto_instance *inst)
151 {
152         struct aead_instance *aead = aead_instance(inst);
153
154         if (!aead->free) {
155                 inst->tmpl->free(inst);
156                 return;
157         }
158
159         aead->free(aead);
160 }
161
162 static const struct crypto_type crypto_aead_type = {
163         .extsize = crypto_alg_extsize,
164         .init_tfm = crypto_aead_init_tfm,
165         .free = crypto_aead_free_instance,
166 #ifdef CONFIG_PROC_FS
167         .show = crypto_aead_show,
168 #endif
169         .report = crypto_aead_report,
170         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
171         .maskset = CRYPTO_ALG_TYPE_MASK,
172         .type = CRYPTO_ALG_TYPE_AEAD,
173         .tfmsize = offsetof(struct crypto_aead, base),
174 };
175
176 static int aead_geniv_setkey(struct crypto_aead *tfm,
177                              const u8 *key, unsigned int keylen)
178 {
179         struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
180
181         return crypto_aead_setkey(ctx->child, key, keylen);
182 }
183
184 static int aead_geniv_setauthsize(struct crypto_aead *tfm,
185                                   unsigned int authsize)
186 {
187         struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
188
189         return crypto_aead_setauthsize(ctx->child, authsize);
190 }
191
192 struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl,
193                                        struct rtattr **tb, u32 type, u32 mask)
194 {
195         const char *name;
196         struct crypto_aead_spawn *spawn;
197         struct crypto_attr_type *algt;
198         struct aead_instance *inst;
199         struct aead_alg *alg;
200         unsigned int ivsize;
201         unsigned int maxauthsize;
202         int err;
203
204         algt = crypto_get_attr_type(tb);
205         if (IS_ERR(algt))
206                 return ERR_CAST(algt);
207
208         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
209                 return ERR_PTR(-EINVAL);
210
211         name = crypto_attr_alg_name(tb[1]);
212         if (IS_ERR(name))
213                 return ERR_CAST(name);
214
215         inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
216         if (!inst)
217                 return ERR_PTR(-ENOMEM);
218
219         spawn = aead_instance_ctx(inst);
220
221         /* Ignore async algorithms if necessary. */
222         mask |= crypto_requires_sync(algt->type, algt->mask);
223
224         crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
225         err = crypto_grab_aead(spawn, name, type, mask);
226         if (err)
227                 goto err_free_inst;
228
229         alg = crypto_spawn_aead_alg(spawn);
230
231         ivsize = crypto_aead_alg_ivsize(alg);
232         maxauthsize = crypto_aead_alg_maxauthsize(alg);
233
234         err = -EINVAL;
235         if (ivsize < sizeof(u64))
236                 goto err_drop_alg;
237
238         err = -ENAMETOOLONG;
239         if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
240                      "%s(%s)", tmpl->name, alg->base.cra_name) >=
241             CRYPTO_MAX_ALG_NAME)
242                 goto err_drop_alg;
243         if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
244                      "%s(%s)", tmpl->name, alg->base.cra_driver_name) >=
245             CRYPTO_MAX_ALG_NAME)
246                 goto err_drop_alg;
247
248         inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
249         inst->alg.base.cra_priority = alg->base.cra_priority;
250         inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
251         inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
252         inst->alg.base.cra_ctxsize = sizeof(struct aead_geniv_ctx);
253
254         inst->alg.setkey = aead_geniv_setkey;
255         inst->alg.setauthsize = aead_geniv_setauthsize;
256
257         inst->alg.ivsize = ivsize;
258         inst->alg.maxauthsize = maxauthsize;
259
260 out:
261         return inst;
262
263 err_drop_alg:
264         crypto_drop_aead(spawn);
265 err_free_inst:
266         kfree(inst);
267         inst = ERR_PTR(err);
268         goto out;
269 }
270 EXPORT_SYMBOL_GPL(aead_geniv_alloc);
271
272 void aead_geniv_free(struct aead_instance *inst)
273 {
274         crypto_drop_aead(aead_instance_ctx(inst));
275         kfree(inst);
276 }
277 EXPORT_SYMBOL_GPL(aead_geniv_free);
278
279 int aead_init_geniv(struct crypto_aead *aead)
280 {
281         struct aead_geniv_ctx *ctx = crypto_aead_ctx(aead);
282         struct aead_instance *inst = aead_alg_instance(aead);
283         struct crypto_aead *child;
284         int err;
285
286         spin_lock_init(&ctx->lock);
287
288         err = crypto_get_default_rng();
289         if (err)
290                 goto out;
291
292         err = crypto_rng_get_bytes(crypto_default_rng, ctx->salt,
293                                    crypto_aead_ivsize(aead));
294         crypto_put_default_rng();
295         if (err)
296                 goto out;
297
298         ctx->sknull = crypto_get_default_null_skcipher2();
299         err = PTR_ERR(ctx->sknull);
300         if (IS_ERR(ctx->sknull))
301                 goto out;
302
303         child = crypto_spawn_aead(aead_instance_ctx(inst));
304         err = PTR_ERR(child);
305         if (IS_ERR(child))
306                 goto drop_null;
307
308         ctx->child = child;
309         crypto_aead_set_reqsize(aead, crypto_aead_reqsize(child) +
310                                       sizeof(struct aead_request));
311
312         err = 0;
313
314 out:
315         return err;
316
317 drop_null:
318         crypto_put_default_null_skcipher2();
319         goto out;
320 }
321 EXPORT_SYMBOL_GPL(aead_init_geniv);
322
323 void aead_exit_geniv(struct crypto_aead *tfm)
324 {
325         struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
326
327         crypto_free_aead(ctx->child);
328         crypto_put_default_null_skcipher2();
329 }
330 EXPORT_SYMBOL_GPL(aead_exit_geniv);
331
332 int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name,
333                      u32 type, u32 mask)
334 {
335         spawn->base.frontend = &crypto_aead_type;
336         return crypto_grab_spawn(&spawn->base, name, type, mask);
337 }
338 EXPORT_SYMBOL_GPL(crypto_grab_aead);
339
340 struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask)
341 {
342         return crypto_alloc_tfm(alg_name, &crypto_aead_type, type, mask);
343 }
344 EXPORT_SYMBOL_GPL(crypto_alloc_aead);
345
346 static int aead_prepare_alg(struct aead_alg *alg)
347 {
348         struct crypto_alg *base = &alg->base;
349
350         if (max3(alg->maxauthsize, alg->ivsize, alg->chunksize) >
351             PAGE_SIZE / 8)
352                 return -EINVAL;
353
354         if (!alg->chunksize)
355                 alg->chunksize = base->cra_blocksize;
356
357         base->cra_type = &crypto_aead_type;
358         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
359         base->cra_flags |= CRYPTO_ALG_TYPE_AEAD;
360
361         return 0;
362 }
363
364 int crypto_register_aead(struct aead_alg *alg)
365 {
366         struct crypto_alg *base = &alg->base;
367         int err;
368
369         err = aead_prepare_alg(alg);
370         if (err)
371                 return err;
372
373         return crypto_register_alg(base);
374 }
375 EXPORT_SYMBOL_GPL(crypto_register_aead);
376
377 void crypto_unregister_aead(struct aead_alg *alg)
378 {
379         crypto_unregister_alg(&alg->base);
380 }
381 EXPORT_SYMBOL_GPL(crypto_unregister_aead);
382
383 int crypto_register_aeads(struct aead_alg *algs, int count)
384 {
385         int i, ret;
386
387         for (i = 0; i < count; i++) {
388                 ret = crypto_register_aead(&algs[i]);
389                 if (ret)
390                         goto err;
391         }
392
393         return 0;
394
395 err:
396         for (--i; i >= 0; --i)
397                 crypto_unregister_aead(&algs[i]);
398
399         return ret;
400 }
401 EXPORT_SYMBOL_GPL(crypto_register_aeads);
402
403 void crypto_unregister_aeads(struct aead_alg *algs, int count)
404 {
405         int i;
406
407         for (i = count - 1; i >= 0; --i)
408                 crypto_unregister_aead(&algs[i]);
409 }
410 EXPORT_SYMBOL_GPL(crypto_unregister_aeads);
411
412 int aead_register_instance(struct crypto_template *tmpl,
413                            struct aead_instance *inst)
414 {
415         int err;
416
417         err = aead_prepare_alg(&inst->alg);
418         if (err)
419                 return err;
420
421         return crypto_register_instance(tmpl, aead_crypto_instance(inst));
422 }
423 EXPORT_SYMBOL_GPL(aead_register_instance);
424
425 MODULE_LICENSE("GPL");
426 MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");