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400c40cf SM |
1 | /* |
2 | * algif_aead: User-space interface for AEAD algorithms | |
3 | * | |
4 | * Copyright (C) 2014, Stephan Mueller <smueller@chronox.de> | |
5 | * | |
6 | * This file provides the user-space API for AEAD ciphers. | |
7 | * | |
8 | * This file is derived from algif_skcipher.c. | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify it | |
11 | * under the terms of the GNU General Public License as published by the Free | |
12 | * Software Foundation; either version 2 of the License, or (at your option) | |
13 | * any later version. | |
14 | */ | |
15 | ||
83094e5e | 16 | #include <crypto/internal/aead.h> |
400c40cf SM |
17 | #include <crypto/scatterwalk.h> |
18 | #include <crypto/if_alg.h> | |
19 | #include <linux/init.h> | |
20 | #include <linux/list.h> | |
21 | #include <linux/kernel.h> | |
22 | #include <linux/mm.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/net.h> | |
25 | #include <net/sock.h> | |
26 | ||
27 | struct aead_sg_list { | |
28 | unsigned int cur; | |
29 | struct scatterlist sg[ALG_MAX_PAGES]; | |
30 | }; | |
31 | ||
83094e5e TS |
32 | struct aead_async_rsgl { |
33 | struct af_alg_sgl sgl; | |
34 | struct list_head list; | |
35 | }; | |
36 | ||
37 | struct aead_async_req { | |
38 | struct scatterlist *tsgl; | |
39 | struct aead_async_rsgl first_rsgl; | |
40 | struct list_head list; | |
41 | struct kiocb *iocb; | |
42 | unsigned int tsgls; | |
43 | char iv[]; | |
44 | }; | |
45 | ||
400c40cf SM |
46 | struct aead_ctx { |
47 | struct aead_sg_list tsgl; | |
83094e5e TS |
48 | struct aead_async_rsgl first_rsgl; |
49 | struct list_head list; | |
400c40cf SM |
50 | |
51 | void *iv; | |
52 | ||
53 | struct af_alg_completion completion; | |
54 | ||
55 | unsigned long used; | |
56 | ||
57 | unsigned int len; | |
58 | bool more; | |
59 | bool merge; | |
60 | bool enc; | |
61 | ||
62 | size_t aead_assoclen; | |
63 | struct aead_request aead_req; | |
64 | }; | |
65 | ||
66 | static inline int aead_sndbuf(struct sock *sk) | |
67 | { | |
68 | struct alg_sock *ask = alg_sk(sk); | |
69 | struct aead_ctx *ctx = ask->private; | |
70 | ||
71 | return max_t(int, max_t(int, sk->sk_sndbuf & PAGE_MASK, PAGE_SIZE) - | |
72 | ctx->used, 0); | |
73 | } | |
74 | ||
75 | static inline bool aead_writable(struct sock *sk) | |
76 | { | |
77 | return PAGE_SIZE <= aead_sndbuf(sk); | |
78 | } | |
79 | ||
80 | static inline bool aead_sufficient_data(struct aead_ctx *ctx) | |
81 | { | |
82 | unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req)); | |
83 | ||
19fa7752 | 84 | return ctx->used >= ctx->aead_assoclen + as; |
400c40cf SM |
85 | } |
86 | ||
83094e5e TS |
87 | static void aead_reset_ctx(struct aead_ctx *ctx) |
88 | { | |
89 | struct aead_sg_list *sgl = &ctx->tsgl; | |
90 | ||
91 | sg_init_table(sgl->sg, ALG_MAX_PAGES); | |
92 | sgl->cur = 0; | |
93 | ctx->used = 0; | |
94 | ctx->more = 0; | |
95 | ctx->merge = 0; | |
96 | } | |
97 | ||
400c40cf SM |
98 | static void aead_put_sgl(struct sock *sk) |
99 | { | |
100 | struct alg_sock *ask = alg_sk(sk); | |
101 | struct aead_ctx *ctx = ask->private; | |
102 | struct aead_sg_list *sgl = &ctx->tsgl; | |
103 | struct scatterlist *sg = sgl->sg; | |
104 | unsigned int i; | |
105 | ||
106 | for (i = 0; i < sgl->cur; i++) { | |
107 | if (!sg_page(sg + i)) | |
108 | continue; | |
109 | ||
110 | put_page(sg_page(sg + i)); | |
111 | sg_assign_page(sg + i, NULL); | |
112 | } | |
83094e5e | 113 | aead_reset_ctx(ctx); |
400c40cf SM |
114 | } |
115 | ||
116 | static void aead_wmem_wakeup(struct sock *sk) | |
117 | { | |
118 | struct socket_wq *wq; | |
119 | ||
120 | if (!aead_writable(sk)) | |
121 | return; | |
122 | ||
123 | rcu_read_lock(); | |
124 | wq = rcu_dereference(sk->sk_wq); | |
1ce0bf50 | 125 | if (skwq_has_sleeper(wq)) |
400c40cf SM |
126 | wake_up_interruptible_sync_poll(&wq->wait, POLLIN | |
127 | POLLRDNORM | | |
128 | POLLRDBAND); | |
129 | sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); | |
130 | rcu_read_unlock(); | |
131 | } | |
132 | ||
133 | static int aead_wait_for_data(struct sock *sk, unsigned flags) | |
134 | { | |
135 | struct alg_sock *ask = alg_sk(sk); | |
136 | struct aead_ctx *ctx = ask->private; | |
137 | long timeout; | |
138 | DEFINE_WAIT(wait); | |
139 | int err = -ERESTARTSYS; | |
140 | ||
141 | if (flags & MSG_DONTWAIT) | |
142 | return -EAGAIN; | |
143 | ||
9cd3e072 | 144 | sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); |
400c40cf SM |
145 | |
146 | for (;;) { | |
147 | if (signal_pending(current)) | |
148 | break; | |
149 | prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); | |
150 | timeout = MAX_SCHEDULE_TIMEOUT; | |
151 | if (sk_wait_event(sk, &timeout, !ctx->more)) { | |
152 | err = 0; | |
153 | break; | |
154 | } | |
155 | } | |
156 | finish_wait(sk_sleep(sk), &wait); | |
157 | ||
9cd3e072 | 158 | sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); |
400c40cf SM |
159 | |
160 | return err; | |
161 | } | |
162 | ||
163 | static void aead_data_wakeup(struct sock *sk) | |
164 | { | |
165 | struct alg_sock *ask = alg_sk(sk); | |
166 | struct aead_ctx *ctx = ask->private; | |
167 | struct socket_wq *wq; | |
168 | ||
169 | if (ctx->more) | |
170 | return; | |
171 | if (!ctx->used) | |
172 | return; | |
173 | ||
174 | rcu_read_lock(); | |
175 | wq = rcu_dereference(sk->sk_wq); | |
1ce0bf50 | 176 | if (skwq_has_sleeper(wq)) |
400c40cf SM |
177 | wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | |
178 | POLLRDNORM | | |
179 | POLLRDBAND); | |
180 | sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); | |
181 | rcu_read_unlock(); | |
182 | } | |
183 | ||
eccd02f3 | 184 | static int aead_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) |
400c40cf SM |
185 | { |
186 | struct sock *sk = sock->sk; | |
187 | struct alg_sock *ask = alg_sk(sk); | |
188 | struct aead_ctx *ctx = ask->private; | |
189 | unsigned ivsize = | |
190 | crypto_aead_ivsize(crypto_aead_reqtfm(&ctx->aead_req)); | |
191 | struct aead_sg_list *sgl = &ctx->tsgl; | |
192 | struct af_alg_control con = {}; | |
193 | long copied = 0; | |
194 | bool enc = 0; | |
195 | bool init = 0; | |
196 | int err = -EINVAL; | |
197 | ||
198 | if (msg->msg_controllen) { | |
199 | err = af_alg_cmsg_send(msg, &con); | |
200 | if (err) | |
201 | return err; | |
202 | ||
203 | init = 1; | |
204 | switch (con.op) { | |
205 | case ALG_OP_ENCRYPT: | |
206 | enc = 1; | |
207 | break; | |
208 | case ALG_OP_DECRYPT: | |
209 | enc = 0; | |
210 | break; | |
211 | default: | |
212 | return -EINVAL; | |
213 | } | |
214 | ||
215 | if (con.iv && con.iv->ivlen != ivsize) | |
216 | return -EINVAL; | |
217 | } | |
218 | ||
219 | lock_sock(sk); | |
220 | if (!ctx->more && ctx->used) | |
221 | goto unlock; | |
222 | ||
223 | if (init) { | |
224 | ctx->enc = enc; | |
225 | if (con.iv) | |
226 | memcpy(ctx->iv, con.iv->iv, ivsize); | |
227 | ||
228 | ctx->aead_assoclen = con.aead_assoclen; | |
229 | } | |
230 | ||
231 | while (size) { | |
652d5b8a | 232 | size_t len = size; |
400c40cf SM |
233 | struct scatterlist *sg = NULL; |
234 | ||
235 | /* use the existing memory in an allocated page */ | |
236 | if (ctx->merge) { | |
237 | sg = sgl->sg + sgl->cur - 1; | |
238 | len = min_t(unsigned long, len, | |
239 | PAGE_SIZE - sg->offset - sg->length); | |
240 | err = memcpy_from_msg(page_address(sg_page(sg)) + | |
241 | sg->offset + sg->length, | |
242 | msg, len); | |
243 | if (err) | |
244 | goto unlock; | |
245 | ||
246 | sg->length += len; | |
247 | ctx->merge = (sg->offset + sg->length) & | |
248 | (PAGE_SIZE - 1); | |
249 | ||
250 | ctx->used += len; | |
251 | copied += len; | |
252 | size -= len; | |
253 | continue; | |
254 | } | |
255 | ||
256 | if (!aead_writable(sk)) { | |
257 | /* user space sent too much data */ | |
258 | aead_put_sgl(sk); | |
259 | err = -EMSGSIZE; | |
260 | goto unlock; | |
261 | } | |
262 | ||
263 | /* allocate a new page */ | |
264 | len = min_t(unsigned long, size, aead_sndbuf(sk)); | |
265 | while (len) { | |
652d5b8a | 266 | size_t plen = 0; |
400c40cf SM |
267 | |
268 | if (sgl->cur >= ALG_MAX_PAGES) { | |
269 | aead_put_sgl(sk); | |
270 | err = -E2BIG; | |
271 | goto unlock; | |
272 | } | |
273 | ||
274 | sg = sgl->sg + sgl->cur; | |
652d5b8a | 275 | plen = min_t(size_t, len, PAGE_SIZE); |
400c40cf SM |
276 | |
277 | sg_assign_page(sg, alloc_page(GFP_KERNEL)); | |
278 | err = -ENOMEM; | |
279 | if (!sg_page(sg)) | |
280 | goto unlock; | |
281 | ||
282 | err = memcpy_from_msg(page_address(sg_page(sg)), | |
283 | msg, plen); | |
284 | if (err) { | |
285 | __free_page(sg_page(sg)); | |
286 | sg_assign_page(sg, NULL); | |
287 | goto unlock; | |
288 | } | |
289 | ||
290 | sg->offset = 0; | |
291 | sg->length = plen; | |
292 | len -= plen; | |
293 | ctx->used += plen; | |
294 | copied += plen; | |
295 | sgl->cur++; | |
296 | size -= plen; | |
297 | ctx->merge = plen & (PAGE_SIZE - 1); | |
298 | } | |
299 | } | |
300 | ||
301 | err = 0; | |
302 | ||
303 | ctx->more = msg->msg_flags & MSG_MORE; | |
304 | if (!ctx->more && !aead_sufficient_data(ctx)) { | |
305 | aead_put_sgl(sk); | |
306 | err = -EMSGSIZE; | |
307 | } | |
308 | ||
309 | unlock: | |
310 | aead_data_wakeup(sk); | |
311 | release_sock(sk); | |
312 | ||
313 | return err ?: copied; | |
314 | } | |
315 | ||
316 | static ssize_t aead_sendpage(struct socket *sock, struct page *page, | |
317 | int offset, size_t size, int flags) | |
318 | { | |
319 | struct sock *sk = sock->sk; | |
320 | struct alg_sock *ask = alg_sk(sk); | |
321 | struct aead_ctx *ctx = ask->private; | |
322 | struct aead_sg_list *sgl = &ctx->tsgl; | |
323 | int err = -EINVAL; | |
324 | ||
325 | if (flags & MSG_SENDPAGE_NOTLAST) | |
326 | flags |= MSG_MORE; | |
327 | ||
328 | if (sgl->cur >= ALG_MAX_PAGES) | |
329 | return -E2BIG; | |
330 | ||
331 | lock_sock(sk); | |
332 | if (!ctx->more && ctx->used) | |
333 | goto unlock; | |
334 | ||
335 | if (!size) | |
336 | goto done; | |
337 | ||
338 | if (!aead_writable(sk)) { | |
339 | /* user space sent too much data */ | |
340 | aead_put_sgl(sk); | |
341 | err = -EMSGSIZE; | |
342 | goto unlock; | |
343 | } | |
344 | ||
345 | ctx->merge = 0; | |
346 | ||
347 | get_page(page); | |
348 | sg_set_page(sgl->sg + sgl->cur, page, size, offset); | |
349 | sgl->cur++; | |
350 | ctx->used += size; | |
351 | ||
352 | err = 0; | |
353 | ||
354 | done: | |
355 | ctx->more = flags & MSG_MORE; | |
356 | if (!ctx->more && !aead_sufficient_data(ctx)) { | |
357 | aead_put_sgl(sk); | |
358 | err = -EMSGSIZE; | |
359 | } | |
360 | ||
361 | unlock: | |
362 | aead_data_wakeup(sk); | |
363 | release_sock(sk); | |
364 | ||
365 | return err ?: size; | |
366 | } | |
367 | ||
83094e5e TS |
368 | #define GET_ASYM_REQ(req, tfm) (struct aead_async_req *) \ |
369 | ((char *)req + sizeof(struct aead_request) + \ | |
370 | crypto_aead_reqsize(tfm)) | |
371 | ||
372 | #define GET_REQ_SIZE(tfm) sizeof(struct aead_async_req) + \ | |
373 | crypto_aead_reqsize(tfm) + crypto_aead_ivsize(tfm) + \ | |
374 | sizeof(struct aead_request) | |
375 | ||
376 | static void aead_async_cb(struct crypto_async_request *_req, int err) | |
377 | { | |
378 | struct sock *sk = _req->data; | |
379 | struct alg_sock *ask = alg_sk(sk); | |
380 | struct aead_ctx *ctx = ask->private; | |
381 | struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req); | |
382 | struct aead_request *req = aead_request_cast(_req); | |
383 | struct aead_async_req *areq = GET_ASYM_REQ(req, tfm); | |
384 | struct scatterlist *sg = areq->tsgl; | |
385 | struct aead_async_rsgl *rsgl; | |
386 | struct kiocb *iocb = areq->iocb; | |
387 | unsigned int i, reqlen = GET_REQ_SIZE(tfm); | |
388 | ||
389 | list_for_each_entry(rsgl, &areq->list, list) { | |
390 | af_alg_free_sg(&rsgl->sgl); | |
391 | if (rsgl != &areq->first_rsgl) | |
392 | sock_kfree_s(sk, rsgl, sizeof(*rsgl)); | |
393 | } | |
394 | ||
395 | for (i = 0; i < areq->tsgls; i++) | |
396 | put_page(sg_page(sg + i)); | |
397 | ||
398 | sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls); | |
399 | sock_kfree_s(sk, req, reqlen); | |
400 | __sock_put(sk); | |
401 | iocb->ki_complete(iocb, err, err); | |
402 | } | |
403 | ||
404 | static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg, | |
405 | int flags) | |
406 | { | |
407 | struct sock *sk = sock->sk; | |
408 | struct alg_sock *ask = alg_sk(sk); | |
409 | struct aead_ctx *ctx = ask->private; | |
410 | struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req); | |
411 | struct aead_async_req *areq; | |
412 | struct aead_request *req = NULL; | |
413 | struct aead_sg_list *sgl = &ctx->tsgl; | |
414 | struct aead_async_rsgl *last_rsgl = NULL, *rsgl; | |
415 | unsigned int as = crypto_aead_authsize(tfm); | |
416 | unsigned int i, reqlen = GET_REQ_SIZE(tfm); | |
417 | int err = -ENOMEM; | |
418 | unsigned long used; | |
419 | size_t outlen; | |
420 | size_t usedpages = 0; | |
421 | ||
422 | lock_sock(sk); | |
423 | if (ctx->more) { | |
424 | err = aead_wait_for_data(sk, flags); | |
425 | if (err) | |
426 | goto unlock; | |
427 | } | |
428 | ||
429 | used = ctx->used; | |
430 | outlen = used; | |
431 | ||
432 | if (!aead_sufficient_data(ctx)) | |
433 | goto unlock; | |
434 | ||
435 | req = sock_kmalloc(sk, reqlen, GFP_KERNEL); | |
436 | if (unlikely(!req)) | |
437 | goto unlock; | |
438 | ||
439 | areq = GET_ASYM_REQ(req, tfm); | |
440 | memset(&areq->first_rsgl, '\0', sizeof(areq->first_rsgl)); | |
441 | INIT_LIST_HEAD(&areq->list); | |
442 | areq->iocb = msg->msg_iocb; | |
443 | memcpy(areq->iv, ctx->iv, crypto_aead_ivsize(tfm)); | |
444 | aead_request_set_tfm(req, tfm); | |
445 | aead_request_set_ad(req, ctx->aead_assoclen); | |
446 | aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, | |
447 | aead_async_cb, sk); | |
448 | used -= ctx->aead_assoclen + (ctx->enc ? as : 0); | |
449 | ||
450 | /* take over all tx sgls from ctx */ | |
451 | areq->tsgl = sock_kmalloc(sk, sizeof(*areq->tsgl) * sgl->cur, | |
452 | GFP_KERNEL); | |
453 | if (unlikely(!areq->tsgl)) | |
454 | goto free; | |
455 | ||
456 | sg_init_table(areq->tsgl, sgl->cur); | |
457 | for (i = 0; i < sgl->cur; i++) | |
458 | sg_set_page(&areq->tsgl[i], sg_page(&sgl->sg[i]), | |
459 | sgl->sg[i].length, sgl->sg[i].offset); | |
460 | ||
461 | areq->tsgls = sgl->cur; | |
462 | ||
463 | /* create rx sgls */ | |
464 | while (iov_iter_count(&msg->msg_iter)) { | |
465 | size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter), | |
466 | (outlen - usedpages)); | |
467 | ||
468 | if (list_empty(&areq->list)) { | |
469 | rsgl = &areq->first_rsgl; | |
470 | ||
471 | } else { | |
472 | rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL); | |
473 | if (unlikely(!rsgl)) { | |
474 | err = -ENOMEM; | |
475 | goto free; | |
476 | } | |
477 | } | |
478 | rsgl->sgl.npages = 0; | |
479 | list_add_tail(&rsgl->list, &areq->list); | |
480 | ||
481 | /* make one iovec available as scatterlist */ | |
482 | err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen); | |
483 | if (err < 0) | |
484 | goto free; | |
485 | ||
486 | usedpages += err; | |
487 | ||
488 | /* chain the new scatterlist with previous one */ | |
489 | if (last_rsgl) | |
490 | af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl); | |
491 | ||
492 | last_rsgl = rsgl; | |
493 | ||
494 | /* we do not need more iovecs as we have sufficient memory */ | |
495 | if (outlen <= usedpages) | |
496 | break; | |
497 | ||
498 | iov_iter_advance(&msg->msg_iter, err); | |
499 | } | |
500 | err = -EINVAL; | |
501 | /* ensure output buffer is sufficiently large */ | |
502 | if (usedpages < outlen) | |
503 | goto free; | |
504 | ||
505 | aead_request_set_crypt(req, areq->tsgl, areq->first_rsgl.sgl.sg, used, | |
506 | areq->iv); | |
507 | err = ctx->enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req); | |
508 | if (err) { | |
509 | if (err == -EINPROGRESS) { | |
510 | sock_hold(sk); | |
511 | err = -EIOCBQUEUED; | |
512 | aead_reset_ctx(ctx); | |
513 | goto unlock; | |
514 | } else if (err == -EBADMSG) { | |
515 | aead_put_sgl(sk); | |
516 | } | |
517 | goto free; | |
518 | } | |
519 | aead_put_sgl(sk); | |
520 | ||
521 | free: | |
522 | list_for_each_entry(rsgl, &areq->list, list) { | |
523 | af_alg_free_sg(&rsgl->sgl); | |
524 | if (rsgl != &areq->first_rsgl) | |
525 | sock_kfree_s(sk, rsgl, sizeof(*rsgl)); | |
526 | } | |
527 | if (areq->tsgl) | |
528 | sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls); | |
529 | if (req) | |
530 | sock_kfree_s(sk, req, reqlen); | |
531 | unlock: | |
532 | aead_wmem_wakeup(sk); | |
533 | release_sock(sk); | |
534 | return err ? err : outlen; | |
535 | } | |
536 | ||
537 | static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags) | |
400c40cf SM |
538 | { |
539 | struct sock *sk = sock->sk; | |
540 | struct alg_sock *ask = alg_sk(sk); | |
541 | struct aead_ctx *ctx = ask->private; | |
400c40cf SM |
542 | unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req)); |
543 | struct aead_sg_list *sgl = &ctx->tsgl; | |
83094e5e TS |
544 | struct aead_async_rsgl *last_rsgl = NULL; |
545 | struct aead_async_rsgl *rsgl, *tmp; | |
400c40cf SM |
546 | int err = -EINVAL; |
547 | unsigned long used = 0; | |
548 | size_t outlen = 0; | |
549 | size_t usedpages = 0; | |
400c40cf SM |
550 | |
551 | lock_sock(sk); | |
552 | ||
553 | /* | |
554 | * AEAD memory structure: For encryption, the tag is appended to the | |
555 | * ciphertext which implies that the memory allocated for the ciphertext | |
556 | * must be increased by the tag length. For decryption, the tag | |
557 | * is expected to be concatenated to the ciphertext. The plaintext | |
558 | * therefore has a memory size of the ciphertext minus the tag length. | |
559 | * | |
560 | * The memory structure for cipher operation has the following | |
561 | * structure: | |
562 | * AEAD encryption input: assoc data || plaintext | |
563 | * AEAD encryption output: cipherntext || auth tag | |
564 | * AEAD decryption input: assoc data || ciphertext || auth tag | |
565 | * AEAD decryption output: plaintext | |
566 | */ | |
567 | ||
568 | if (ctx->more) { | |
569 | err = aead_wait_for_data(sk, flags); | |
570 | if (err) | |
571 | goto unlock; | |
572 | } | |
573 | ||
574 | used = ctx->used; | |
575 | ||
576 | /* | |
577 | * Make sure sufficient data is present -- note, the same check is | |
578 | * is also present in sendmsg/sendpage. The checks in sendpage/sendmsg | |
579 | * shall provide an information to the data sender that something is | |
580 | * wrong, but they are irrelevant to maintain the kernel integrity. | |
581 | * We need this check here too in case user space decides to not honor | |
582 | * the error message in sendmsg/sendpage and still call recvmsg. This | |
583 | * check here protects the kernel integrity. | |
584 | */ | |
585 | if (!aead_sufficient_data(ctx)) | |
586 | goto unlock; | |
587 | ||
19fa7752 HX |
588 | outlen = used; |
589 | ||
400c40cf SM |
590 | /* |
591 | * The cipher operation input data is reduced by the associated data | |
592 | * length as this data is processed separately later on. | |
593 | */ | |
19fa7752 | 594 | used -= ctx->aead_assoclen + (ctx->enc ? as : 0); |
400c40cf SM |
595 | |
596 | /* convert iovecs of output buffers into scatterlists */ | |
597 | while (iov_iter_count(&msg->msg_iter)) { | |
598 | size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter), | |
599 | (outlen - usedpages)); | |
600 | ||
83094e5e TS |
601 | if (list_empty(&ctx->list)) { |
602 | rsgl = &ctx->first_rsgl; | |
603 | } else { | |
604 | rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL); | |
605 | if (unlikely(!rsgl)) { | |
606 | err = -ENOMEM; | |
607 | goto unlock; | |
608 | } | |
609 | } | |
610 | rsgl->sgl.npages = 0; | |
611 | list_add_tail(&rsgl->list, &ctx->list); | |
612 | ||
400c40cf | 613 | /* make one iovec available as scatterlist */ |
83094e5e | 614 | err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen); |
400c40cf SM |
615 | if (err < 0) |
616 | goto unlock; | |
617 | usedpages += err; | |
7b2a18e0 | 618 | /* chain the new scatterlist with previous one */ |
83094e5e TS |
619 | if (last_rsgl) |
620 | af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl); | |
621 | ||
622 | last_rsgl = rsgl; | |
7b2a18e0 | 623 | |
400c40cf SM |
624 | /* we do not need more iovecs as we have sufficient memory */ |
625 | if (outlen <= usedpages) | |
626 | break; | |
627 | iov_iter_advance(&msg->msg_iter, err); | |
400c40cf SM |
628 | } |
629 | ||
630 | err = -EINVAL; | |
631 | /* ensure output buffer is sufficiently large */ | |
632 | if (usedpages < outlen) | |
633 | goto unlock; | |
634 | ||
19fa7752 | 635 | sg_mark_end(sgl->sg + sgl->cur - 1); |
83094e5e | 636 | aead_request_set_crypt(&ctx->aead_req, sgl->sg, ctx->first_rsgl.sgl.sg, |
19fa7752 HX |
637 | used, ctx->iv); |
638 | aead_request_set_ad(&ctx->aead_req, ctx->aead_assoclen); | |
400c40cf SM |
639 | |
640 | err = af_alg_wait_for_completion(ctx->enc ? | |
641 | crypto_aead_encrypt(&ctx->aead_req) : | |
642 | crypto_aead_decrypt(&ctx->aead_req), | |
643 | &ctx->completion); | |
644 | ||
645 | if (err) { | |
646 | /* EBADMSG implies a valid cipher operation took place */ | |
647 | if (err == -EBADMSG) | |
648 | aead_put_sgl(sk); | |
83094e5e | 649 | |
400c40cf SM |
650 | goto unlock; |
651 | } | |
652 | ||
653 | aead_put_sgl(sk); | |
400c40cf SM |
654 | err = 0; |
655 | ||
656 | unlock: | |
83094e5e TS |
657 | list_for_each_entry_safe(rsgl, tmp, &ctx->list, list) { |
658 | af_alg_free_sg(&rsgl->sgl); | |
659 | if (rsgl != &ctx->first_rsgl) | |
660 | sock_kfree_s(sk, rsgl, sizeof(*rsgl)); | |
661 | list_del(&rsgl->list); | |
662 | } | |
663 | INIT_LIST_HEAD(&ctx->list); | |
400c40cf SM |
664 | aead_wmem_wakeup(sk); |
665 | release_sock(sk); | |
666 | ||
667 | return err ? err : outlen; | |
668 | } | |
669 | ||
83094e5e TS |
670 | static int aead_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored, |
671 | int flags) | |
672 | { | |
673 | return (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) ? | |
674 | aead_recvmsg_async(sock, msg, flags) : | |
675 | aead_recvmsg_sync(sock, msg, flags); | |
676 | } | |
677 | ||
400c40cf SM |
678 | static unsigned int aead_poll(struct file *file, struct socket *sock, |
679 | poll_table *wait) | |
680 | { | |
681 | struct sock *sk = sock->sk; | |
682 | struct alg_sock *ask = alg_sk(sk); | |
683 | struct aead_ctx *ctx = ask->private; | |
684 | unsigned int mask; | |
685 | ||
686 | sock_poll_wait(file, sk_sleep(sk), wait); | |
687 | mask = 0; | |
688 | ||
689 | if (!ctx->more) | |
690 | mask |= POLLIN | POLLRDNORM; | |
691 | ||
692 | if (aead_writable(sk)) | |
693 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; | |
694 | ||
695 | return mask; | |
696 | } | |
697 | ||
698 | static struct proto_ops algif_aead_ops = { | |
699 | .family = PF_ALG, | |
700 | ||
701 | .connect = sock_no_connect, | |
702 | .socketpair = sock_no_socketpair, | |
703 | .getname = sock_no_getname, | |
704 | .ioctl = sock_no_ioctl, | |
705 | .listen = sock_no_listen, | |
706 | .shutdown = sock_no_shutdown, | |
707 | .getsockopt = sock_no_getsockopt, | |
708 | .mmap = sock_no_mmap, | |
709 | .bind = sock_no_bind, | |
710 | .accept = sock_no_accept, | |
711 | .setsockopt = sock_no_setsockopt, | |
712 | ||
713 | .release = af_alg_release, | |
714 | .sendmsg = aead_sendmsg, | |
715 | .sendpage = aead_sendpage, | |
716 | .recvmsg = aead_recvmsg, | |
717 | .poll = aead_poll, | |
718 | }; | |
719 | ||
720 | static void *aead_bind(const char *name, u32 type, u32 mask) | |
721 | { | |
5e4b8c1f | 722 | return crypto_alloc_aead(name, type, mask); |
400c40cf SM |
723 | } |
724 | ||
725 | static void aead_release(void *private) | |
726 | { | |
727 | crypto_free_aead(private); | |
728 | } | |
729 | ||
730 | static int aead_setauthsize(void *private, unsigned int authsize) | |
731 | { | |
732 | return crypto_aead_setauthsize(private, authsize); | |
733 | } | |
734 | ||
735 | static int aead_setkey(void *private, const u8 *key, unsigned int keylen) | |
736 | { | |
737 | return crypto_aead_setkey(private, key, keylen); | |
738 | } | |
739 | ||
740 | static void aead_sock_destruct(struct sock *sk) | |
741 | { | |
742 | struct alg_sock *ask = alg_sk(sk); | |
743 | struct aead_ctx *ctx = ask->private; | |
744 | unsigned int ivlen = crypto_aead_ivsize( | |
745 | crypto_aead_reqtfm(&ctx->aead_req)); | |
746 | ||
83094e5e | 747 | WARN_ON(atomic_read(&sk->sk_refcnt) != 0); |
400c40cf SM |
748 | aead_put_sgl(sk); |
749 | sock_kzfree_s(sk, ctx->iv, ivlen); | |
750 | sock_kfree_s(sk, ctx, ctx->len); | |
751 | af_alg_release_parent(sk); | |
752 | } | |
753 | ||
754 | static int aead_accept_parent(void *private, struct sock *sk) | |
755 | { | |
756 | struct aead_ctx *ctx; | |
757 | struct alg_sock *ask = alg_sk(sk); | |
758 | unsigned int len = sizeof(*ctx) + crypto_aead_reqsize(private); | |
759 | unsigned int ivlen = crypto_aead_ivsize(private); | |
760 | ||
761 | ctx = sock_kmalloc(sk, len, GFP_KERNEL); | |
762 | if (!ctx) | |
763 | return -ENOMEM; | |
764 | memset(ctx, 0, len); | |
765 | ||
766 | ctx->iv = sock_kmalloc(sk, ivlen, GFP_KERNEL); | |
767 | if (!ctx->iv) { | |
768 | sock_kfree_s(sk, ctx, len); | |
769 | return -ENOMEM; | |
770 | } | |
771 | memset(ctx->iv, 0, ivlen); | |
772 | ||
773 | ctx->len = len; | |
774 | ctx->used = 0; | |
775 | ctx->more = 0; | |
776 | ctx->merge = 0; | |
777 | ctx->enc = 0; | |
778 | ctx->tsgl.cur = 0; | |
779 | ctx->aead_assoclen = 0; | |
780 | af_alg_init_completion(&ctx->completion); | |
781 | sg_init_table(ctx->tsgl.sg, ALG_MAX_PAGES); | |
83094e5e | 782 | INIT_LIST_HEAD(&ctx->list); |
400c40cf SM |
783 | |
784 | ask->private = ctx; | |
785 | ||
786 | aead_request_set_tfm(&ctx->aead_req, private); | |
787 | aead_request_set_callback(&ctx->aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG, | |
788 | af_alg_complete, &ctx->completion); | |
789 | ||
790 | sk->sk_destruct = aead_sock_destruct; | |
791 | ||
792 | return 0; | |
793 | } | |
794 | ||
795 | static const struct af_alg_type algif_type_aead = { | |
796 | .bind = aead_bind, | |
797 | .release = aead_release, | |
798 | .setkey = aead_setkey, | |
799 | .setauthsize = aead_setauthsize, | |
800 | .accept = aead_accept_parent, | |
801 | .ops = &algif_aead_ops, | |
802 | .name = "aead", | |
803 | .owner = THIS_MODULE | |
804 | }; | |
805 | ||
806 | static int __init algif_aead_init(void) | |
807 | { | |
808 | return af_alg_register_type(&algif_type_aead); | |
809 | } | |
810 | ||
811 | static void __exit algif_aead_exit(void) | |
812 | { | |
813 | int err = af_alg_unregister_type(&algif_type_aead); | |
814 | BUG_ON(err); | |
815 | } | |
816 | ||
817 | module_init(algif_aead_init); | |
818 | module_exit(algif_aead_exit); | |
819 | MODULE_LICENSE("GPL"); | |
820 | MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>"); | |
821 | MODULE_DESCRIPTION("AEAD kernel crypto API user space interface"); |