Commit | Line | Data |
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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> | |
174cd4b1 | 22 | #include <linux/sched/signal.h> |
400c40cf SM |
23 | #include <linux/mm.h> |
24 | #include <linux/module.h> | |
25 | #include <linux/net.h> | |
26 | #include <net/sock.h> | |
27 | ||
28 | struct aead_sg_list { | |
29 | unsigned int cur; | |
30 | struct scatterlist sg[ALG_MAX_PAGES]; | |
31 | }; | |
32 | ||
83094e5e TS |
33 | struct aead_async_rsgl { |
34 | struct af_alg_sgl sgl; | |
35 | struct list_head list; | |
36 | }; | |
37 | ||
38 | struct aead_async_req { | |
39 | struct scatterlist *tsgl; | |
40 | struct aead_async_rsgl first_rsgl; | |
41 | struct list_head list; | |
42 | struct kiocb *iocb; | |
e6534aeb | 43 | struct sock *sk; |
83094e5e TS |
44 | unsigned int tsgls; |
45 | char iv[]; | |
46 | }; | |
47 | ||
2a2a251f SM |
48 | struct aead_tfm { |
49 | struct crypto_aead *aead; | |
50 | bool has_key; | |
51 | }; | |
52 | ||
400c40cf SM |
53 | struct aead_ctx { |
54 | struct aead_sg_list tsgl; | |
83094e5e TS |
55 | struct aead_async_rsgl first_rsgl; |
56 | struct list_head list; | |
400c40cf SM |
57 | |
58 | void *iv; | |
59 | ||
60 | struct af_alg_completion completion; | |
61 | ||
62 | unsigned long used; | |
63 | ||
64 | unsigned int len; | |
65 | bool more; | |
66 | bool merge; | |
67 | bool enc; | |
68 | ||
69 | size_t aead_assoclen; | |
70 | struct aead_request aead_req; | |
71 | }; | |
72 | ||
73 | static inline int aead_sndbuf(struct sock *sk) | |
74 | { | |
75 | struct alg_sock *ask = alg_sk(sk); | |
76 | struct aead_ctx *ctx = ask->private; | |
77 | ||
78 | return max_t(int, max_t(int, sk->sk_sndbuf & PAGE_MASK, PAGE_SIZE) - | |
79 | ctx->used, 0); | |
80 | } | |
81 | ||
82 | static inline bool aead_writable(struct sock *sk) | |
83 | { | |
84 | return PAGE_SIZE <= aead_sndbuf(sk); | |
85 | } | |
86 | ||
87 | static inline bool aead_sufficient_data(struct aead_ctx *ctx) | |
88 | { | |
89 | unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req)); | |
90 | ||
0c1e16cd SM |
91 | /* |
92 | * The minimum amount of memory needed for an AEAD cipher is | |
93 | * the AAD and in case of decryption the tag. | |
94 | */ | |
95 | return ctx->used >= ctx->aead_assoclen + (ctx->enc ? 0 : as); | |
400c40cf SM |
96 | } |
97 | ||
83094e5e TS |
98 | static void aead_reset_ctx(struct aead_ctx *ctx) |
99 | { | |
100 | struct aead_sg_list *sgl = &ctx->tsgl; | |
101 | ||
102 | sg_init_table(sgl->sg, ALG_MAX_PAGES); | |
103 | sgl->cur = 0; | |
104 | ctx->used = 0; | |
105 | ctx->more = 0; | |
106 | ctx->merge = 0; | |
107 | } | |
108 | ||
400c40cf SM |
109 | static void aead_put_sgl(struct sock *sk) |
110 | { | |
111 | struct alg_sock *ask = alg_sk(sk); | |
112 | struct aead_ctx *ctx = ask->private; | |
113 | struct aead_sg_list *sgl = &ctx->tsgl; | |
114 | struct scatterlist *sg = sgl->sg; | |
115 | unsigned int i; | |
116 | ||
117 | for (i = 0; i < sgl->cur; i++) { | |
118 | if (!sg_page(sg + i)) | |
119 | continue; | |
120 | ||
121 | put_page(sg_page(sg + i)); | |
122 | sg_assign_page(sg + i, NULL); | |
123 | } | |
83094e5e | 124 | aead_reset_ctx(ctx); |
400c40cf SM |
125 | } |
126 | ||
127 | static void aead_wmem_wakeup(struct sock *sk) | |
128 | { | |
129 | struct socket_wq *wq; | |
130 | ||
131 | if (!aead_writable(sk)) | |
132 | return; | |
133 | ||
134 | rcu_read_lock(); | |
135 | wq = rcu_dereference(sk->sk_wq); | |
1ce0bf50 | 136 | if (skwq_has_sleeper(wq)) |
400c40cf SM |
137 | wake_up_interruptible_sync_poll(&wq->wait, POLLIN | |
138 | POLLRDNORM | | |
139 | POLLRDBAND); | |
140 | sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); | |
141 | rcu_read_unlock(); | |
142 | } | |
143 | ||
144 | static int aead_wait_for_data(struct sock *sk, unsigned flags) | |
145 | { | |
d9dc8b0f | 146 | DEFINE_WAIT_FUNC(wait, woken_wake_function); |
400c40cf SM |
147 | struct alg_sock *ask = alg_sk(sk); |
148 | struct aead_ctx *ctx = ask->private; | |
149 | long timeout; | |
400c40cf SM |
150 | int err = -ERESTARTSYS; |
151 | ||
152 | if (flags & MSG_DONTWAIT) | |
153 | return -EAGAIN; | |
154 | ||
9cd3e072 | 155 | sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); |
d9dc8b0f | 156 | add_wait_queue(sk_sleep(sk), &wait); |
400c40cf SM |
157 | for (;;) { |
158 | if (signal_pending(current)) | |
159 | break; | |
400c40cf | 160 | timeout = MAX_SCHEDULE_TIMEOUT; |
d9dc8b0f | 161 | if (sk_wait_event(sk, &timeout, !ctx->more, &wait)) { |
400c40cf SM |
162 | err = 0; |
163 | break; | |
164 | } | |
165 | } | |
d9dc8b0f | 166 | remove_wait_queue(sk_sleep(sk), &wait); |
400c40cf | 167 | |
9cd3e072 | 168 | sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); |
400c40cf SM |
169 | |
170 | return err; | |
171 | } | |
172 | ||
173 | static void aead_data_wakeup(struct sock *sk) | |
174 | { | |
175 | struct alg_sock *ask = alg_sk(sk); | |
176 | struct aead_ctx *ctx = ask->private; | |
177 | struct socket_wq *wq; | |
178 | ||
179 | if (ctx->more) | |
180 | return; | |
181 | if (!ctx->used) | |
182 | return; | |
183 | ||
184 | rcu_read_lock(); | |
185 | wq = rcu_dereference(sk->sk_wq); | |
1ce0bf50 | 186 | if (skwq_has_sleeper(wq)) |
400c40cf SM |
187 | wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | |
188 | POLLRDNORM | | |
189 | POLLRDBAND); | |
190 | sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); | |
191 | rcu_read_unlock(); | |
192 | } | |
193 | ||
eccd02f3 | 194 | static int aead_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) |
400c40cf SM |
195 | { |
196 | struct sock *sk = sock->sk; | |
197 | struct alg_sock *ask = alg_sk(sk); | |
198 | struct aead_ctx *ctx = ask->private; | |
199 | unsigned ivsize = | |
200 | crypto_aead_ivsize(crypto_aead_reqtfm(&ctx->aead_req)); | |
201 | struct aead_sg_list *sgl = &ctx->tsgl; | |
202 | struct af_alg_control con = {}; | |
203 | long copied = 0; | |
204 | bool enc = 0; | |
205 | bool init = 0; | |
206 | int err = -EINVAL; | |
207 | ||
208 | if (msg->msg_controllen) { | |
209 | err = af_alg_cmsg_send(msg, &con); | |
210 | if (err) | |
211 | return err; | |
212 | ||
213 | init = 1; | |
214 | switch (con.op) { | |
215 | case ALG_OP_ENCRYPT: | |
216 | enc = 1; | |
217 | break; | |
218 | case ALG_OP_DECRYPT: | |
219 | enc = 0; | |
220 | break; | |
221 | default: | |
222 | return -EINVAL; | |
223 | } | |
224 | ||
225 | if (con.iv && con.iv->ivlen != ivsize) | |
226 | return -EINVAL; | |
227 | } | |
228 | ||
229 | lock_sock(sk); | |
230 | if (!ctx->more && ctx->used) | |
231 | goto unlock; | |
232 | ||
233 | if (init) { | |
234 | ctx->enc = enc; | |
235 | if (con.iv) | |
236 | memcpy(ctx->iv, con.iv->iv, ivsize); | |
237 | ||
238 | ctx->aead_assoclen = con.aead_assoclen; | |
239 | } | |
240 | ||
241 | while (size) { | |
652d5b8a | 242 | size_t len = size; |
400c40cf SM |
243 | struct scatterlist *sg = NULL; |
244 | ||
245 | /* use the existing memory in an allocated page */ | |
246 | if (ctx->merge) { | |
247 | sg = sgl->sg + sgl->cur - 1; | |
248 | len = min_t(unsigned long, len, | |
249 | PAGE_SIZE - sg->offset - sg->length); | |
250 | err = memcpy_from_msg(page_address(sg_page(sg)) + | |
251 | sg->offset + sg->length, | |
252 | msg, len); | |
253 | if (err) | |
254 | goto unlock; | |
255 | ||
256 | sg->length += len; | |
257 | ctx->merge = (sg->offset + sg->length) & | |
258 | (PAGE_SIZE - 1); | |
259 | ||
260 | ctx->used += len; | |
261 | copied += len; | |
262 | size -= len; | |
263 | continue; | |
264 | } | |
265 | ||
266 | if (!aead_writable(sk)) { | |
267 | /* user space sent too much data */ | |
268 | aead_put_sgl(sk); | |
269 | err = -EMSGSIZE; | |
270 | goto unlock; | |
271 | } | |
272 | ||
273 | /* allocate a new page */ | |
274 | len = min_t(unsigned long, size, aead_sndbuf(sk)); | |
275 | while (len) { | |
652d5b8a | 276 | size_t plen = 0; |
400c40cf SM |
277 | |
278 | if (sgl->cur >= ALG_MAX_PAGES) { | |
279 | aead_put_sgl(sk); | |
280 | err = -E2BIG; | |
281 | goto unlock; | |
282 | } | |
283 | ||
284 | sg = sgl->sg + sgl->cur; | |
652d5b8a | 285 | plen = min_t(size_t, len, PAGE_SIZE); |
400c40cf SM |
286 | |
287 | sg_assign_page(sg, alloc_page(GFP_KERNEL)); | |
288 | err = -ENOMEM; | |
289 | if (!sg_page(sg)) | |
290 | goto unlock; | |
291 | ||
292 | err = memcpy_from_msg(page_address(sg_page(sg)), | |
293 | msg, plen); | |
294 | if (err) { | |
295 | __free_page(sg_page(sg)); | |
296 | sg_assign_page(sg, NULL); | |
297 | goto unlock; | |
298 | } | |
299 | ||
300 | sg->offset = 0; | |
301 | sg->length = plen; | |
302 | len -= plen; | |
303 | ctx->used += plen; | |
304 | copied += plen; | |
305 | sgl->cur++; | |
306 | size -= plen; | |
307 | ctx->merge = plen & (PAGE_SIZE - 1); | |
308 | } | |
309 | } | |
310 | ||
311 | err = 0; | |
312 | ||
313 | ctx->more = msg->msg_flags & MSG_MORE; | |
314 | if (!ctx->more && !aead_sufficient_data(ctx)) { | |
315 | aead_put_sgl(sk); | |
316 | err = -EMSGSIZE; | |
317 | } | |
318 | ||
319 | unlock: | |
320 | aead_data_wakeup(sk); | |
321 | release_sock(sk); | |
322 | ||
323 | return err ?: copied; | |
324 | } | |
325 | ||
326 | static ssize_t aead_sendpage(struct socket *sock, struct page *page, | |
327 | int offset, size_t size, int flags) | |
328 | { | |
329 | struct sock *sk = sock->sk; | |
330 | struct alg_sock *ask = alg_sk(sk); | |
331 | struct aead_ctx *ctx = ask->private; | |
332 | struct aead_sg_list *sgl = &ctx->tsgl; | |
333 | int err = -EINVAL; | |
334 | ||
335 | if (flags & MSG_SENDPAGE_NOTLAST) | |
336 | flags |= MSG_MORE; | |
337 | ||
338 | if (sgl->cur >= ALG_MAX_PAGES) | |
339 | return -E2BIG; | |
340 | ||
341 | lock_sock(sk); | |
342 | if (!ctx->more && ctx->used) | |
343 | goto unlock; | |
344 | ||
345 | if (!size) | |
346 | goto done; | |
347 | ||
348 | if (!aead_writable(sk)) { | |
349 | /* user space sent too much data */ | |
350 | aead_put_sgl(sk); | |
351 | err = -EMSGSIZE; | |
352 | goto unlock; | |
353 | } | |
354 | ||
355 | ctx->merge = 0; | |
356 | ||
357 | get_page(page); | |
358 | sg_set_page(sgl->sg + sgl->cur, page, size, offset); | |
359 | sgl->cur++; | |
360 | ctx->used += size; | |
361 | ||
362 | err = 0; | |
363 | ||
364 | done: | |
365 | ctx->more = flags & MSG_MORE; | |
366 | if (!ctx->more && !aead_sufficient_data(ctx)) { | |
367 | aead_put_sgl(sk); | |
368 | err = -EMSGSIZE; | |
369 | } | |
370 | ||
371 | unlock: | |
372 | aead_data_wakeup(sk); | |
373 | release_sock(sk); | |
374 | ||
375 | return err ?: size; | |
376 | } | |
377 | ||
83094e5e TS |
378 | #define GET_ASYM_REQ(req, tfm) (struct aead_async_req *) \ |
379 | ((char *)req + sizeof(struct aead_request) + \ | |
380 | crypto_aead_reqsize(tfm)) | |
381 | ||
382 | #define GET_REQ_SIZE(tfm) sizeof(struct aead_async_req) + \ | |
383 | crypto_aead_reqsize(tfm) + crypto_aead_ivsize(tfm) + \ | |
384 | sizeof(struct aead_request) | |
385 | ||
386 | static void aead_async_cb(struct crypto_async_request *_req, int err) | |
387 | { | |
e6534aeb HX |
388 | struct aead_request *req = _req->data; |
389 | struct crypto_aead *tfm = crypto_aead_reqtfm(req); | |
83094e5e | 390 | struct aead_async_req *areq = GET_ASYM_REQ(req, tfm); |
e6534aeb | 391 | struct sock *sk = areq->sk; |
83094e5e TS |
392 | struct scatterlist *sg = areq->tsgl; |
393 | struct aead_async_rsgl *rsgl; | |
394 | struct kiocb *iocb = areq->iocb; | |
395 | unsigned int i, reqlen = GET_REQ_SIZE(tfm); | |
396 | ||
397 | list_for_each_entry(rsgl, &areq->list, list) { | |
398 | af_alg_free_sg(&rsgl->sgl); | |
399 | if (rsgl != &areq->first_rsgl) | |
400 | sock_kfree_s(sk, rsgl, sizeof(*rsgl)); | |
401 | } | |
402 | ||
403 | for (i = 0; i < areq->tsgls; i++) | |
404 | put_page(sg_page(sg + i)); | |
405 | ||
406 | sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls); | |
407 | sock_kfree_s(sk, req, reqlen); | |
408 | __sock_put(sk); | |
409 | iocb->ki_complete(iocb, err, err); | |
410 | } | |
411 | ||
412 | static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg, | |
413 | int flags) | |
414 | { | |
415 | struct sock *sk = sock->sk; | |
416 | struct alg_sock *ask = alg_sk(sk); | |
417 | struct aead_ctx *ctx = ask->private; | |
418 | struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req); | |
419 | struct aead_async_req *areq; | |
420 | struct aead_request *req = NULL; | |
421 | struct aead_sg_list *sgl = &ctx->tsgl; | |
422 | struct aead_async_rsgl *last_rsgl = NULL, *rsgl; | |
423 | unsigned int as = crypto_aead_authsize(tfm); | |
424 | unsigned int i, reqlen = GET_REQ_SIZE(tfm); | |
425 | int err = -ENOMEM; | |
426 | unsigned long used; | |
678b5c6b | 427 | size_t outlen = 0; |
83094e5e TS |
428 | size_t usedpages = 0; |
429 | ||
430 | lock_sock(sk); | |
431 | if (ctx->more) { | |
432 | err = aead_wait_for_data(sk, flags); | |
433 | if (err) | |
434 | goto unlock; | |
435 | } | |
436 | ||
83094e5e TS |
437 | if (!aead_sufficient_data(ctx)) |
438 | goto unlock; | |
439 | ||
0c1e16cd SM |
440 | used = ctx->used; |
441 | if (ctx->enc) | |
442 | outlen = used + as; | |
443 | else | |
444 | outlen = used - as; | |
445 | ||
83094e5e TS |
446 | req = sock_kmalloc(sk, reqlen, GFP_KERNEL); |
447 | if (unlikely(!req)) | |
448 | goto unlock; | |
449 | ||
450 | areq = GET_ASYM_REQ(req, tfm); | |
451 | memset(&areq->first_rsgl, '\0', sizeof(areq->first_rsgl)); | |
452 | INIT_LIST_HEAD(&areq->list); | |
453 | areq->iocb = msg->msg_iocb; | |
e6534aeb | 454 | areq->sk = sk; |
83094e5e TS |
455 | memcpy(areq->iv, ctx->iv, crypto_aead_ivsize(tfm)); |
456 | aead_request_set_tfm(req, tfm); | |
457 | aead_request_set_ad(req, ctx->aead_assoclen); | |
458 | aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, | |
e6534aeb | 459 | aead_async_cb, req); |
0c1e16cd | 460 | used -= ctx->aead_assoclen; |
83094e5e TS |
461 | |
462 | /* take over all tx sgls from ctx */ | |
5937d81a SM |
463 | areq->tsgl = sock_kmalloc(sk, |
464 | sizeof(*areq->tsgl) * max_t(u32, sgl->cur, 1), | |
83094e5e TS |
465 | GFP_KERNEL); |
466 | if (unlikely(!areq->tsgl)) | |
467 | goto free; | |
468 | ||
5937d81a | 469 | sg_init_table(areq->tsgl, max_t(u32, sgl->cur, 1)); |
83094e5e TS |
470 | for (i = 0; i < sgl->cur; i++) |
471 | sg_set_page(&areq->tsgl[i], sg_page(&sgl->sg[i]), | |
472 | sgl->sg[i].length, sgl->sg[i].offset); | |
473 | ||
474 | areq->tsgls = sgl->cur; | |
475 | ||
476 | /* create rx sgls */ | |
0c1e16cd | 477 | while (outlen > usedpages && iov_iter_count(&msg->msg_iter)) { |
83094e5e TS |
478 | size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter), |
479 | (outlen - usedpages)); | |
480 | ||
481 | if (list_empty(&areq->list)) { | |
482 | rsgl = &areq->first_rsgl; | |
483 | ||
484 | } else { | |
485 | rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL); | |
486 | if (unlikely(!rsgl)) { | |
487 | err = -ENOMEM; | |
488 | goto free; | |
489 | } | |
490 | } | |
491 | rsgl->sgl.npages = 0; | |
492 | list_add_tail(&rsgl->list, &areq->list); | |
493 | ||
494 | /* make one iovec available as scatterlist */ | |
495 | err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen); | |
496 | if (err < 0) | |
497 | goto free; | |
498 | ||
499 | usedpages += err; | |
500 | ||
501 | /* chain the new scatterlist with previous one */ | |
502 | if (last_rsgl) | |
503 | af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl); | |
504 | ||
505 | last_rsgl = rsgl; | |
506 | ||
83094e5e TS |
507 | iov_iter_advance(&msg->msg_iter, err); |
508 | } | |
0c1e16cd | 509 | |
83094e5e | 510 | /* ensure output buffer is sufficiently large */ |
0c1e16cd SM |
511 | if (usedpages < outlen) { |
512 | err = -EINVAL; | |
513 | goto unlock; | |
514 | } | |
83094e5e TS |
515 | |
516 | aead_request_set_crypt(req, areq->tsgl, areq->first_rsgl.sgl.sg, used, | |
517 | areq->iv); | |
518 | err = ctx->enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req); | |
519 | if (err) { | |
520 | if (err == -EINPROGRESS) { | |
521 | sock_hold(sk); | |
522 | err = -EIOCBQUEUED; | |
523 | aead_reset_ctx(ctx); | |
524 | goto unlock; | |
525 | } else if (err == -EBADMSG) { | |
526 | aead_put_sgl(sk); | |
527 | } | |
528 | goto free; | |
529 | } | |
530 | aead_put_sgl(sk); | |
531 | ||
532 | free: | |
533 | list_for_each_entry(rsgl, &areq->list, list) { | |
534 | af_alg_free_sg(&rsgl->sgl); | |
535 | if (rsgl != &areq->first_rsgl) | |
536 | sock_kfree_s(sk, rsgl, sizeof(*rsgl)); | |
537 | } | |
538 | if (areq->tsgl) | |
539 | sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls); | |
540 | if (req) | |
541 | sock_kfree_s(sk, req, reqlen); | |
542 | unlock: | |
543 | aead_wmem_wakeup(sk); | |
544 | release_sock(sk); | |
545 | return err ? err : outlen; | |
546 | } | |
547 | ||
548 | static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags) | |
400c40cf SM |
549 | { |
550 | struct sock *sk = sock->sk; | |
551 | struct alg_sock *ask = alg_sk(sk); | |
552 | struct aead_ctx *ctx = ask->private; | |
400c40cf SM |
553 | unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req)); |
554 | struct aead_sg_list *sgl = &ctx->tsgl; | |
83094e5e TS |
555 | struct aead_async_rsgl *last_rsgl = NULL; |
556 | struct aead_async_rsgl *rsgl, *tmp; | |
400c40cf SM |
557 | int err = -EINVAL; |
558 | unsigned long used = 0; | |
559 | size_t outlen = 0; | |
560 | size_t usedpages = 0; | |
400c40cf SM |
561 | |
562 | lock_sock(sk); | |
563 | ||
564 | /* | |
3f692d5f SM |
565 | * Please see documentation of aead_request_set_crypt for the |
566 | * description of the AEAD memory structure expected from the caller. | |
400c40cf SM |
567 | */ |
568 | ||
569 | if (ctx->more) { | |
570 | err = aead_wait_for_data(sk, flags); | |
571 | if (err) | |
572 | goto unlock; | |
573 | } | |
574 | ||
0c1e16cd | 575 | /* data length provided by caller via sendmsg/sendpage */ |
400c40cf SM |
576 | used = ctx->used; |
577 | ||
578 | /* | |
579 | * Make sure sufficient data is present -- note, the same check is | |
580 | * is also present in sendmsg/sendpage. The checks in sendpage/sendmsg | |
581 | * shall provide an information to the data sender that something is | |
582 | * wrong, but they are irrelevant to maintain the kernel integrity. | |
583 | * We need this check here too in case user space decides to not honor | |
584 | * the error message in sendmsg/sendpage and still call recvmsg. This | |
585 | * check here protects the kernel integrity. | |
586 | */ | |
587 | if (!aead_sufficient_data(ctx)) | |
588 | goto unlock; | |
589 | ||
0c1e16cd SM |
590 | /* |
591 | * Calculate the minimum output buffer size holding the result of the | |
592 | * cipher operation. When encrypting data, the receiving buffer is | |
593 | * larger by the tag length compared to the input buffer as the | |
594 | * encryption operation generates the tag. For decryption, the input | |
595 | * buffer provides the tag which is consumed resulting in only the | |
596 | * plaintext without a buffer for the tag returned to the caller. | |
597 | */ | |
598 | if (ctx->enc) | |
599 | outlen = used + as; | |
600 | else | |
601 | outlen = used - as; | |
19fa7752 | 602 | |
400c40cf SM |
603 | /* |
604 | * The cipher operation input data is reduced by the associated data | |
605 | * length as this data is processed separately later on. | |
606 | */ | |
0c1e16cd | 607 | used -= ctx->aead_assoclen; |
400c40cf SM |
608 | |
609 | /* convert iovecs of output buffers into scatterlists */ | |
0c1e16cd | 610 | while (outlen > usedpages && iov_iter_count(&msg->msg_iter)) { |
400c40cf SM |
611 | size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter), |
612 | (outlen - usedpages)); | |
613 | ||
83094e5e TS |
614 | if (list_empty(&ctx->list)) { |
615 | rsgl = &ctx->first_rsgl; | |
616 | } else { | |
617 | rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL); | |
618 | if (unlikely(!rsgl)) { | |
619 | err = -ENOMEM; | |
620 | goto unlock; | |
621 | } | |
622 | } | |
623 | rsgl->sgl.npages = 0; | |
624 | list_add_tail(&rsgl->list, &ctx->list); | |
625 | ||
400c40cf | 626 | /* make one iovec available as scatterlist */ |
83094e5e | 627 | err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen); |
400c40cf SM |
628 | if (err < 0) |
629 | goto unlock; | |
630 | usedpages += err; | |
7b2a18e0 | 631 | /* chain the new scatterlist with previous one */ |
83094e5e TS |
632 | if (last_rsgl) |
633 | af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl); | |
634 | ||
635 | last_rsgl = rsgl; | |
7b2a18e0 | 636 | |
400c40cf | 637 | iov_iter_advance(&msg->msg_iter, err); |
400c40cf SM |
638 | } |
639 | ||
400c40cf | 640 | /* ensure output buffer is sufficiently large */ |
0c1e16cd SM |
641 | if (usedpages < outlen) { |
642 | err = -EINVAL; | |
400c40cf | 643 | goto unlock; |
0c1e16cd | 644 | } |
400c40cf | 645 | |
19fa7752 | 646 | sg_mark_end(sgl->sg + sgl->cur - 1); |
83094e5e | 647 | aead_request_set_crypt(&ctx->aead_req, sgl->sg, ctx->first_rsgl.sgl.sg, |
19fa7752 HX |
648 | used, ctx->iv); |
649 | aead_request_set_ad(&ctx->aead_req, ctx->aead_assoclen); | |
400c40cf SM |
650 | |
651 | err = af_alg_wait_for_completion(ctx->enc ? | |
652 | crypto_aead_encrypt(&ctx->aead_req) : | |
653 | crypto_aead_decrypt(&ctx->aead_req), | |
654 | &ctx->completion); | |
655 | ||
656 | if (err) { | |
657 | /* EBADMSG implies a valid cipher operation took place */ | |
658 | if (err == -EBADMSG) | |
659 | aead_put_sgl(sk); | |
83094e5e | 660 | |
400c40cf SM |
661 | goto unlock; |
662 | } | |
663 | ||
664 | aead_put_sgl(sk); | |
400c40cf SM |
665 | err = 0; |
666 | ||
667 | unlock: | |
83094e5e TS |
668 | list_for_each_entry_safe(rsgl, tmp, &ctx->list, list) { |
669 | af_alg_free_sg(&rsgl->sgl); | |
0b529f14 | 670 | list_del(&rsgl->list); |
83094e5e TS |
671 | if (rsgl != &ctx->first_rsgl) |
672 | sock_kfree_s(sk, rsgl, sizeof(*rsgl)); | |
83094e5e TS |
673 | } |
674 | INIT_LIST_HEAD(&ctx->list); | |
400c40cf SM |
675 | aead_wmem_wakeup(sk); |
676 | release_sock(sk); | |
677 | ||
678 | return err ? err : outlen; | |
679 | } | |
680 | ||
83094e5e TS |
681 | static int aead_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored, |
682 | int flags) | |
683 | { | |
684 | return (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) ? | |
685 | aead_recvmsg_async(sock, msg, flags) : | |
686 | aead_recvmsg_sync(sock, msg, flags); | |
687 | } | |
688 | ||
400c40cf SM |
689 | static unsigned int aead_poll(struct file *file, struct socket *sock, |
690 | poll_table *wait) | |
691 | { | |
692 | struct sock *sk = sock->sk; | |
693 | struct alg_sock *ask = alg_sk(sk); | |
694 | struct aead_ctx *ctx = ask->private; | |
695 | unsigned int mask; | |
696 | ||
697 | sock_poll_wait(file, sk_sleep(sk), wait); | |
698 | mask = 0; | |
699 | ||
700 | if (!ctx->more) | |
701 | mask |= POLLIN | POLLRDNORM; | |
702 | ||
703 | if (aead_writable(sk)) | |
704 | mask |= POLLOUT | POLLWRNORM | POLLWRBAND; | |
705 | ||
706 | return mask; | |
707 | } | |
708 | ||
709 | static struct proto_ops algif_aead_ops = { | |
710 | .family = PF_ALG, | |
711 | ||
712 | .connect = sock_no_connect, | |
713 | .socketpair = sock_no_socketpair, | |
714 | .getname = sock_no_getname, | |
715 | .ioctl = sock_no_ioctl, | |
716 | .listen = sock_no_listen, | |
717 | .shutdown = sock_no_shutdown, | |
718 | .getsockopt = sock_no_getsockopt, | |
719 | .mmap = sock_no_mmap, | |
720 | .bind = sock_no_bind, | |
721 | .accept = sock_no_accept, | |
722 | .setsockopt = sock_no_setsockopt, | |
723 | ||
724 | .release = af_alg_release, | |
725 | .sendmsg = aead_sendmsg, | |
726 | .sendpage = aead_sendpage, | |
727 | .recvmsg = aead_recvmsg, | |
728 | .poll = aead_poll, | |
729 | }; | |
730 | ||
2a2a251f SM |
731 | static int aead_check_key(struct socket *sock) |
732 | { | |
733 | int err = 0; | |
734 | struct sock *psk; | |
735 | struct alg_sock *pask; | |
736 | struct aead_tfm *tfm; | |
737 | struct sock *sk = sock->sk; | |
738 | struct alg_sock *ask = alg_sk(sk); | |
739 | ||
740 | lock_sock(sk); | |
741 | if (ask->refcnt) | |
742 | goto unlock_child; | |
743 | ||
744 | psk = ask->parent; | |
745 | pask = alg_sk(ask->parent); | |
746 | tfm = pask->private; | |
747 | ||
748 | err = -ENOKEY; | |
749 | lock_sock_nested(psk, SINGLE_DEPTH_NESTING); | |
750 | if (!tfm->has_key) | |
751 | goto unlock; | |
752 | ||
753 | if (!pask->refcnt++) | |
754 | sock_hold(psk); | |
755 | ||
756 | ask->refcnt = 1; | |
757 | sock_put(psk); | |
758 | ||
759 | err = 0; | |
760 | ||
761 | unlock: | |
762 | release_sock(psk); | |
763 | unlock_child: | |
764 | release_sock(sk); | |
765 | ||
766 | return err; | |
767 | } | |
768 | ||
769 | static int aead_sendmsg_nokey(struct socket *sock, struct msghdr *msg, | |
770 | size_t size) | |
771 | { | |
772 | int err; | |
773 | ||
774 | err = aead_check_key(sock); | |
775 | if (err) | |
776 | return err; | |
777 | ||
778 | return aead_sendmsg(sock, msg, size); | |
779 | } | |
780 | ||
781 | static ssize_t aead_sendpage_nokey(struct socket *sock, struct page *page, | |
782 | int offset, size_t size, int flags) | |
783 | { | |
784 | int err; | |
785 | ||
786 | err = aead_check_key(sock); | |
787 | if (err) | |
788 | return err; | |
789 | ||
790 | return aead_sendpage(sock, page, offset, size, flags); | |
791 | } | |
792 | ||
793 | static int aead_recvmsg_nokey(struct socket *sock, struct msghdr *msg, | |
794 | size_t ignored, int flags) | |
795 | { | |
796 | int err; | |
797 | ||
798 | err = aead_check_key(sock); | |
799 | if (err) | |
800 | return err; | |
801 | ||
802 | return aead_recvmsg(sock, msg, ignored, flags); | |
803 | } | |
804 | ||
805 | static struct proto_ops algif_aead_ops_nokey = { | |
806 | .family = PF_ALG, | |
807 | ||
808 | .connect = sock_no_connect, | |
809 | .socketpair = sock_no_socketpair, | |
810 | .getname = sock_no_getname, | |
811 | .ioctl = sock_no_ioctl, | |
812 | .listen = sock_no_listen, | |
813 | .shutdown = sock_no_shutdown, | |
814 | .getsockopt = sock_no_getsockopt, | |
815 | .mmap = sock_no_mmap, | |
816 | .bind = sock_no_bind, | |
817 | .accept = sock_no_accept, | |
818 | .setsockopt = sock_no_setsockopt, | |
819 | ||
820 | .release = af_alg_release, | |
821 | .sendmsg = aead_sendmsg_nokey, | |
822 | .sendpage = aead_sendpage_nokey, | |
823 | .recvmsg = aead_recvmsg_nokey, | |
824 | .poll = aead_poll, | |
825 | }; | |
826 | ||
400c40cf SM |
827 | static void *aead_bind(const char *name, u32 type, u32 mask) |
828 | { | |
2a2a251f SM |
829 | struct aead_tfm *tfm; |
830 | struct crypto_aead *aead; | |
831 | ||
832 | tfm = kzalloc(sizeof(*tfm), GFP_KERNEL); | |
833 | if (!tfm) | |
834 | return ERR_PTR(-ENOMEM); | |
835 | ||
836 | aead = crypto_alloc_aead(name, type, mask); | |
837 | if (IS_ERR(aead)) { | |
838 | kfree(tfm); | |
839 | return ERR_CAST(aead); | |
840 | } | |
841 | ||
842 | tfm->aead = aead; | |
843 | ||
844 | return tfm; | |
400c40cf SM |
845 | } |
846 | ||
847 | static void aead_release(void *private) | |
848 | { | |
2a2a251f SM |
849 | struct aead_tfm *tfm = private; |
850 | ||
851 | crypto_free_aead(tfm->aead); | |
852 | kfree(tfm); | |
400c40cf SM |
853 | } |
854 | ||
855 | static int aead_setauthsize(void *private, unsigned int authsize) | |
856 | { | |
2a2a251f SM |
857 | struct aead_tfm *tfm = private; |
858 | ||
859 | return crypto_aead_setauthsize(tfm->aead, authsize); | |
400c40cf SM |
860 | } |
861 | ||
862 | static int aead_setkey(void *private, const u8 *key, unsigned int keylen) | |
863 | { | |
2a2a251f SM |
864 | struct aead_tfm *tfm = private; |
865 | int err; | |
866 | ||
867 | err = crypto_aead_setkey(tfm->aead, key, keylen); | |
868 | tfm->has_key = !err; | |
869 | ||
870 | return err; | |
400c40cf SM |
871 | } |
872 | ||
873 | static void aead_sock_destruct(struct sock *sk) | |
874 | { | |
875 | struct alg_sock *ask = alg_sk(sk); | |
876 | struct aead_ctx *ctx = ask->private; | |
877 | unsigned int ivlen = crypto_aead_ivsize( | |
878 | crypto_aead_reqtfm(&ctx->aead_req)); | |
879 | ||
41c6d650 | 880 | WARN_ON(refcount_read(&sk->sk_refcnt) != 0); |
400c40cf SM |
881 | aead_put_sgl(sk); |
882 | sock_kzfree_s(sk, ctx->iv, ivlen); | |
883 | sock_kfree_s(sk, ctx, ctx->len); | |
884 | af_alg_release_parent(sk); | |
885 | } | |
886 | ||
2a2a251f | 887 | static int aead_accept_parent_nokey(void *private, struct sock *sk) |
400c40cf SM |
888 | { |
889 | struct aead_ctx *ctx; | |
890 | struct alg_sock *ask = alg_sk(sk); | |
2a2a251f SM |
891 | struct aead_tfm *tfm = private; |
892 | struct crypto_aead *aead = tfm->aead; | |
893 | unsigned int len = sizeof(*ctx) + crypto_aead_reqsize(aead); | |
894 | unsigned int ivlen = crypto_aead_ivsize(aead); | |
400c40cf SM |
895 | |
896 | ctx = sock_kmalloc(sk, len, GFP_KERNEL); | |
897 | if (!ctx) | |
898 | return -ENOMEM; | |
899 | memset(ctx, 0, len); | |
900 | ||
901 | ctx->iv = sock_kmalloc(sk, ivlen, GFP_KERNEL); | |
902 | if (!ctx->iv) { | |
903 | sock_kfree_s(sk, ctx, len); | |
904 | return -ENOMEM; | |
905 | } | |
906 | memset(ctx->iv, 0, ivlen); | |
907 | ||
908 | ctx->len = len; | |
909 | ctx->used = 0; | |
910 | ctx->more = 0; | |
911 | ctx->merge = 0; | |
912 | ctx->enc = 0; | |
913 | ctx->tsgl.cur = 0; | |
914 | ctx->aead_assoclen = 0; | |
915 | af_alg_init_completion(&ctx->completion); | |
916 | sg_init_table(ctx->tsgl.sg, ALG_MAX_PAGES); | |
83094e5e | 917 | INIT_LIST_HEAD(&ctx->list); |
400c40cf SM |
918 | |
919 | ask->private = ctx; | |
920 | ||
2a2a251f | 921 | aead_request_set_tfm(&ctx->aead_req, aead); |
400c40cf SM |
922 | aead_request_set_callback(&ctx->aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG, |
923 | af_alg_complete, &ctx->completion); | |
924 | ||
925 | sk->sk_destruct = aead_sock_destruct; | |
926 | ||
927 | return 0; | |
928 | } | |
929 | ||
2a2a251f SM |
930 | static int aead_accept_parent(void *private, struct sock *sk) |
931 | { | |
932 | struct aead_tfm *tfm = private; | |
933 | ||
934 | if (!tfm->has_key) | |
935 | return -ENOKEY; | |
936 | ||
937 | return aead_accept_parent_nokey(private, sk); | |
938 | } | |
939 | ||
400c40cf SM |
940 | static const struct af_alg_type algif_type_aead = { |
941 | .bind = aead_bind, | |
942 | .release = aead_release, | |
943 | .setkey = aead_setkey, | |
944 | .setauthsize = aead_setauthsize, | |
945 | .accept = aead_accept_parent, | |
2a2a251f | 946 | .accept_nokey = aead_accept_parent_nokey, |
400c40cf | 947 | .ops = &algif_aead_ops, |
2a2a251f | 948 | .ops_nokey = &algif_aead_ops_nokey, |
400c40cf SM |
949 | .name = "aead", |
950 | .owner = THIS_MODULE | |
951 | }; | |
952 | ||
953 | static int __init algif_aead_init(void) | |
954 | { | |
955 | return af_alg_register_type(&algif_type_aead); | |
956 | } | |
957 | ||
958 | static void __exit algif_aead_exit(void) | |
959 | { | |
960 | int err = af_alg_unregister_type(&algif_type_aead); | |
961 | BUG_ON(err); | |
962 | } | |
963 | ||
964 | module_init(algif_aead_init); | |
965 | module_exit(algif_aead_exit); | |
966 | MODULE_LICENSE("GPL"); | |
967 | MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>"); | |
968 | MODULE_DESCRIPTION("AEAD kernel crypto API user space interface"); |