Version:  2.0.40 2.2.26 2.4.37 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10

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

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