blob: 3bc0e76eaaefe740154dab41d3f09ed75194ec9a
1 | /* |
2 | * Asynchronous block chaining cipher operations. |
3 | * |
4 | * This is the asynchronous version of blkcipher.c indicating completion |
5 | * via a callback. |
6 | * |
7 | * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> |
8 | * |
9 | * This program is free software; you can redistribute it and/or modify it |
10 | * under the terms of the GNU General Public License as published by the Free |
11 | * Software Foundation; either version 2 of the License, or (at your option) |
12 | * any later version. |
13 | * |
14 | */ |
15 | |
16 | #include <crypto/internal/skcipher.h> |
17 | #include <linux/err.h> |
18 | #include <linux/kernel.h> |
19 | #include <linux/slab.h> |
20 | #include <linux/seq_file.h> |
21 | #include <linux/cryptouser.h> |
22 | #include <net/netlink.h> |
23 | |
24 | #include <crypto/scatterwalk.h> |
25 | |
26 | #include "internal.h" |
27 | |
28 | struct ablkcipher_buffer { |
29 | struct list_head entry; |
30 | struct scatter_walk dst; |
31 | unsigned int len; |
32 | void *data; |
33 | }; |
34 | |
35 | enum { |
36 | ABLKCIPHER_WALK_SLOW = 1 << 0, |
37 | }; |
38 | |
39 | static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p) |
40 | { |
41 | scatterwalk_copychunks(p->data, &p->dst, p->len, 1); |
42 | } |
43 | |
44 | void __ablkcipher_walk_complete(struct ablkcipher_walk *walk) |
45 | { |
46 | struct ablkcipher_buffer *p, *tmp; |
47 | |
48 | list_for_each_entry_safe(p, tmp, &walk->buffers, entry) { |
49 | ablkcipher_buffer_write(p); |
50 | list_del(&p->entry); |
51 | kfree(p); |
52 | } |
53 | } |
54 | EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete); |
55 | |
56 | static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk, |
57 | struct ablkcipher_buffer *p) |
58 | { |
59 | p->dst = walk->out; |
60 | list_add_tail(&p->entry, &walk->buffers); |
61 | } |
62 | |
63 | /* Get a spot of the specified length that does not straddle a page. |
64 | * The caller needs to ensure that there is enough space for this operation. |
65 | */ |
66 | static inline u8 *ablkcipher_get_spot(u8 *start, unsigned int len) |
67 | { |
68 | u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK); |
69 | |
70 | return max(start, end_page); |
71 | } |
72 | |
73 | static inline void ablkcipher_done_slow(struct ablkcipher_walk *walk, |
74 | unsigned int n) |
75 | { |
76 | for (;;) { |
77 | unsigned int len_this_page = scatterwalk_pagelen(&walk->out); |
78 | |
79 | if (len_this_page > n) |
80 | len_this_page = n; |
81 | scatterwalk_advance(&walk->out, n); |
82 | if (n == len_this_page) |
83 | break; |
84 | n -= len_this_page; |
85 | scatterwalk_start(&walk->out, sg_next(walk->out.sg)); |
86 | } |
87 | } |
88 | |
89 | static inline void ablkcipher_done_fast(struct ablkcipher_walk *walk, |
90 | unsigned int n) |
91 | { |
92 | scatterwalk_advance(&walk->in, n); |
93 | scatterwalk_advance(&walk->out, n); |
94 | } |
95 | |
96 | static int ablkcipher_walk_next(struct ablkcipher_request *req, |
97 | struct ablkcipher_walk *walk); |
98 | |
99 | int ablkcipher_walk_done(struct ablkcipher_request *req, |
100 | struct ablkcipher_walk *walk, int err) |
101 | { |
102 | struct crypto_tfm *tfm = req->base.tfm; |
103 | unsigned int n; /* bytes processed */ |
104 | bool more; |
105 | |
106 | if (unlikely(err < 0)) |
107 | goto finish; |
108 | |
109 | n = walk->nbytes - err; |
110 | walk->total -= n; |
111 | more = (walk->total != 0); |
112 | |
113 | if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW))) { |
114 | ablkcipher_done_fast(walk, n); |
115 | } else { |
116 | if (WARN_ON(err)) { |
117 | /* unexpected case; didn't process all bytes */ |
118 | err = -EINVAL; |
119 | goto finish; |
120 | } |
121 | ablkcipher_done_slow(walk, n); |
122 | } |
123 | |
124 | scatterwalk_done(&walk->in, 0, more); |
125 | scatterwalk_done(&walk->out, 1, more); |
126 | |
127 | if (more) { |
128 | crypto_yield(req->base.flags); |
129 | return ablkcipher_walk_next(req, walk); |
130 | } |
131 | err = 0; |
132 | finish: |
133 | walk->nbytes = 0; |
134 | if (walk->iv != req->info) |
135 | memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize); |
136 | kfree(walk->iv_buffer); |
137 | return err; |
138 | } |
139 | EXPORT_SYMBOL_GPL(ablkcipher_walk_done); |
140 | |
141 | static inline int ablkcipher_next_slow(struct ablkcipher_request *req, |
142 | struct ablkcipher_walk *walk, |
143 | unsigned int bsize, |
144 | unsigned int alignmask, |
145 | void **src_p, void **dst_p) |
146 | { |
147 | unsigned aligned_bsize = ALIGN(bsize, alignmask + 1); |
148 | struct ablkcipher_buffer *p; |
149 | void *src, *dst, *base; |
150 | unsigned int n; |
151 | |
152 | n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1); |
153 | n += (aligned_bsize * 3 - (alignmask + 1) + |
154 | (alignmask & ~(crypto_tfm_ctx_alignment() - 1))); |
155 | |
156 | p = kmalloc(n, GFP_ATOMIC); |
157 | if (!p) |
158 | return ablkcipher_walk_done(req, walk, -ENOMEM); |
159 | |
160 | base = p + 1; |
161 | |
162 | dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1); |
163 | src = dst = ablkcipher_get_spot(dst, bsize); |
164 | |
165 | p->len = bsize; |
166 | p->data = dst; |
167 | |
168 | scatterwalk_copychunks(src, &walk->in, bsize, 0); |
169 | |
170 | ablkcipher_queue_write(walk, p); |
171 | |
172 | walk->nbytes = bsize; |
173 | walk->flags |= ABLKCIPHER_WALK_SLOW; |
174 | |
175 | *src_p = src; |
176 | *dst_p = dst; |
177 | |
178 | return 0; |
179 | } |
180 | |
181 | static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk, |
182 | struct crypto_tfm *tfm, |
183 | unsigned int alignmask) |
184 | { |
185 | unsigned bs = walk->blocksize; |
186 | unsigned int ivsize = tfm->crt_ablkcipher.ivsize; |
187 | unsigned aligned_bs = ALIGN(bs, alignmask + 1); |
188 | unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) - |
189 | (alignmask + 1); |
190 | u8 *iv; |
191 | |
192 | size += alignmask & ~(crypto_tfm_ctx_alignment() - 1); |
193 | walk->iv_buffer = kmalloc(size, GFP_ATOMIC); |
194 | if (!walk->iv_buffer) |
195 | return -ENOMEM; |
196 | |
197 | iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1); |
198 | iv = ablkcipher_get_spot(iv, bs) + aligned_bs; |
199 | iv = ablkcipher_get_spot(iv, bs) + aligned_bs; |
200 | iv = ablkcipher_get_spot(iv, ivsize); |
201 | |
202 | walk->iv = memcpy(iv, walk->iv, ivsize); |
203 | return 0; |
204 | } |
205 | |
206 | static inline int ablkcipher_next_fast(struct ablkcipher_request *req, |
207 | struct ablkcipher_walk *walk) |
208 | { |
209 | walk->src.page = scatterwalk_page(&walk->in); |
210 | walk->src.offset = offset_in_page(walk->in.offset); |
211 | walk->dst.page = scatterwalk_page(&walk->out); |
212 | walk->dst.offset = offset_in_page(walk->out.offset); |
213 | |
214 | return 0; |
215 | } |
216 | |
217 | static int ablkcipher_walk_next(struct ablkcipher_request *req, |
218 | struct ablkcipher_walk *walk) |
219 | { |
220 | struct crypto_tfm *tfm = req->base.tfm; |
221 | unsigned int alignmask, bsize, n; |
222 | void *src, *dst; |
223 | int err; |
224 | |
225 | alignmask = crypto_tfm_alg_alignmask(tfm); |
226 | n = walk->total; |
227 | if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) { |
228 | req->base.flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN; |
229 | return ablkcipher_walk_done(req, walk, -EINVAL); |
230 | } |
231 | |
232 | walk->flags &= ~ABLKCIPHER_WALK_SLOW; |
233 | src = dst = NULL; |
234 | |
235 | bsize = min(walk->blocksize, n); |
236 | n = scatterwalk_clamp(&walk->in, n); |
237 | n = scatterwalk_clamp(&walk->out, n); |
238 | |
239 | if (n < bsize || |
240 | !scatterwalk_aligned(&walk->in, alignmask) || |
241 | !scatterwalk_aligned(&walk->out, alignmask)) { |
242 | err = ablkcipher_next_slow(req, walk, bsize, alignmask, |
243 | &src, &dst); |
244 | goto set_phys_lowmem; |
245 | } |
246 | |
247 | walk->nbytes = n; |
248 | |
249 | return ablkcipher_next_fast(req, walk); |
250 | |
251 | set_phys_lowmem: |
252 | if (err >= 0) { |
253 | walk->src.page = virt_to_page(src); |
254 | walk->dst.page = virt_to_page(dst); |
255 | walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1)); |
256 | walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1)); |
257 | } |
258 | |
259 | return err; |
260 | } |
261 | |
262 | static int ablkcipher_walk_first(struct ablkcipher_request *req, |
263 | struct ablkcipher_walk *walk) |
264 | { |
265 | struct crypto_tfm *tfm = req->base.tfm; |
266 | unsigned int alignmask; |
267 | |
268 | alignmask = crypto_tfm_alg_alignmask(tfm); |
269 | if (WARN_ON_ONCE(in_irq())) |
270 | return -EDEADLK; |
271 | |
272 | walk->iv = req->info; |
273 | walk->nbytes = walk->total; |
274 | if (unlikely(!walk->total)) |
275 | return 0; |
276 | |
277 | walk->iv_buffer = NULL; |
278 | if (unlikely(((unsigned long)walk->iv & alignmask))) { |
279 | int err = ablkcipher_copy_iv(walk, tfm, alignmask); |
280 | |
281 | if (err) |
282 | return err; |
283 | } |
284 | |
285 | scatterwalk_start(&walk->in, walk->in.sg); |
286 | scatterwalk_start(&walk->out, walk->out.sg); |
287 | |
288 | return ablkcipher_walk_next(req, walk); |
289 | } |
290 | |
291 | int ablkcipher_walk_phys(struct ablkcipher_request *req, |
292 | struct ablkcipher_walk *walk) |
293 | { |
294 | walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm); |
295 | return ablkcipher_walk_first(req, walk); |
296 | } |
297 | EXPORT_SYMBOL_GPL(ablkcipher_walk_phys); |
298 | |
299 | static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key, |
300 | unsigned int keylen) |
301 | { |
302 | struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm); |
303 | unsigned long alignmask = crypto_ablkcipher_alignmask(tfm); |
304 | int ret; |
305 | u8 *buffer, *alignbuffer; |
306 | unsigned long absize; |
307 | |
308 | absize = keylen + alignmask; |
309 | buffer = kmalloc(absize, GFP_ATOMIC); |
310 | if (!buffer) |
311 | return -ENOMEM; |
312 | |
313 | alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); |
314 | memcpy(alignbuffer, key, keylen); |
315 | ret = cipher->setkey(tfm, alignbuffer, keylen); |
316 | memset(alignbuffer, 0, keylen); |
317 | kfree(buffer); |
318 | return ret; |
319 | } |
320 | |
321 | static int setkey(struct crypto_ablkcipher *tfm, const u8 *key, |
322 | unsigned int keylen) |
323 | { |
324 | struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm); |
325 | unsigned long alignmask = crypto_ablkcipher_alignmask(tfm); |
326 | |
327 | if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) { |
328 | crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); |
329 | return -EINVAL; |
330 | } |
331 | |
332 | if ((unsigned long)key & alignmask) |
333 | return setkey_unaligned(tfm, key, keylen); |
334 | |
335 | return cipher->setkey(tfm, key, keylen); |
336 | } |
337 | |
338 | static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type, |
339 | u32 mask) |
340 | { |
341 | return alg->cra_ctxsize; |
342 | } |
343 | |
344 | static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type, |
345 | u32 mask) |
346 | { |
347 | struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher; |
348 | struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher; |
349 | |
350 | if (alg->ivsize > PAGE_SIZE / 8) |
351 | return -EINVAL; |
352 | |
353 | crt->setkey = setkey; |
354 | crt->encrypt = alg->encrypt; |
355 | crt->decrypt = alg->decrypt; |
356 | crt->base = __crypto_ablkcipher_cast(tfm); |
357 | crt->ivsize = alg->ivsize; |
358 | |
359 | return 0; |
360 | } |
361 | |
362 | #ifdef CONFIG_NET |
363 | static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg) |
364 | { |
365 | struct crypto_report_blkcipher rblkcipher; |
366 | |
367 | strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type)); |
368 | strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>", |
369 | sizeof(rblkcipher.geniv)); |
370 | rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0'; |
371 | |
372 | rblkcipher.blocksize = alg->cra_blocksize; |
373 | rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize; |
374 | rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize; |
375 | rblkcipher.ivsize = alg->cra_ablkcipher.ivsize; |
376 | |
377 | if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER, |
378 | sizeof(struct crypto_report_blkcipher), &rblkcipher)) |
379 | goto nla_put_failure; |
380 | return 0; |
381 | |
382 | nla_put_failure: |
383 | return -EMSGSIZE; |
384 | } |
385 | #else |
386 | static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg) |
387 | { |
388 | return -ENOSYS; |
389 | } |
390 | #endif |
391 | |
392 | static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg) |
393 | __attribute__ ((unused)); |
394 | static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg) |
395 | { |
396 | struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher; |
397 | |
398 | seq_printf(m, "type : ablkcipher\n"); |
399 | seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ? |
400 | "yes" : "no"); |
401 | seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); |
402 | seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize); |
403 | seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize); |
404 | seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize); |
405 | seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>"); |
406 | } |
407 | |
408 | const struct crypto_type crypto_ablkcipher_type = { |
409 | .ctxsize = crypto_ablkcipher_ctxsize, |
410 | .init = crypto_init_ablkcipher_ops, |
411 | #ifdef CONFIG_PROC_FS |
412 | .show = crypto_ablkcipher_show, |
413 | #endif |
414 | .report = crypto_ablkcipher_report, |
415 | }; |
416 | EXPORT_SYMBOL_GPL(crypto_ablkcipher_type); |
417 | |
418 | static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type, |
419 | u32 mask) |
420 | { |
421 | struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher; |
422 | struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher; |
423 | |
424 | if (alg->ivsize > PAGE_SIZE / 8) |
425 | return -EINVAL; |
426 | |
427 | crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ? |
428 | alg->setkey : setkey; |
429 | crt->encrypt = alg->encrypt; |
430 | crt->decrypt = alg->decrypt; |
431 | crt->base = __crypto_ablkcipher_cast(tfm); |
432 | crt->ivsize = alg->ivsize; |
433 | |
434 | return 0; |
435 | } |
436 | |
437 | #ifdef CONFIG_NET |
438 | static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg) |
439 | { |
440 | struct crypto_report_blkcipher rblkcipher; |
441 | |
442 | strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type)); |
443 | strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>", |
444 | sizeof(rblkcipher.geniv)); |
445 | rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0'; |
446 | |
447 | rblkcipher.blocksize = alg->cra_blocksize; |
448 | rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize; |
449 | rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize; |
450 | rblkcipher.ivsize = alg->cra_ablkcipher.ivsize; |
451 | |
452 | if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER, |
453 | sizeof(struct crypto_report_blkcipher), &rblkcipher)) |
454 | goto nla_put_failure; |
455 | return 0; |
456 | |
457 | nla_put_failure: |
458 | return -EMSGSIZE; |
459 | } |
460 | #else |
461 | static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg) |
462 | { |
463 | return -ENOSYS; |
464 | } |
465 | #endif |
466 | |
467 | static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg) |
468 | __attribute__ ((unused)); |
469 | static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg) |
470 | { |
471 | struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher; |
472 | |
473 | seq_printf(m, "type : givcipher\n"); |
474 | seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ? |
475 | "yes" : "no"); |
476 | seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); |
477 | seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize); |
478 | seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize); |
479 | seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize); |
480 | seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>"); |
481 | } |
482 | |
483 | const struct crypto_type crypto_givcipher_type = { |
484 | .ctxsize = crypto_ablkcipher_ctxsize, |
485 | .init = crypto_init_givcipher_ops, |
486 | #ifdef CONFIG_PROC_FS |
487 | .show = crypto_givcipher_show, |
488 | #endif |
489 | .report = crypto_givcipher_report, |
490 | }; |
491 | EXPORT_SYMBOL_GPL(crypto_givcipher_type); |
492 |