Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 16 | #include <crypto/internal/aead.h> |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 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 | |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 46 | struct aead_ctx { |
| 47 | struct aead_sg_list tsgl; |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 48 | struct aead_async_rsgl first_rsgl; |
| 49 | struct list_head list; |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Herbert Xu | 19fa775 | 2015-05-27 17:24:41 +0800 | [diff] [blame] | 84 | return ctx->used >= ctx->aead_assoclen + as; |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 85 | } |
| 86 | |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 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 | |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | } |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 113 | aead_reset_ctx(ctx); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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); |
Herbert Xu | 1ce0bf5 | 2015-11-26 13:55:39 +0800 | [diff] [blame] | 125 | if (skwq_has_sleeper(wq)) |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Eric Dumazet | 9cd3e07 | 2015-11-29 20:03:10 -0800 | [diff] [blame] | 144 | sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Eric Dumazet | 9cd3e07 | 2015-11-29 20:03:10 -0800 | [diff] [blame] | 158 | sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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); |
Herbert Xu | 1ce0bf5 | 2015-11-26 13:55:39 +0800 | [diff] [blame] | 176 | if (skwq_has_sleeper(wq)) |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Linus Torvalds | eccd02f | 2015-04-15 14:09:46 -0700 | [diff] [blame] | 184 | static int aead_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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) { |
LABBE Corentin | 652d5b8 | 2015-10-23 14:10:36 +0200 | [diff] [blame] | 232 | size_t len = size; |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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) { |
LABBE Corentin | 652d5b8 | 2015-10-23 14:10:36 +0200 | [diff] [blame] | 266 | size_t plen = 0; |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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; |
LABBE Corentin | 652d5b8 | 2015-10-23 14:10:36 +0200 | [diff] [blame] | 275 | plen = min_t(size_t, len, PAGE_SIZE); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 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) |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 538 | { |
| 539 | struct sock *sk = sock->sk; |
| 540 | struct alg_sock *ask = alg_sk(sk); |
| 541 | struct aead_ctx *ctx = ask->private; |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 542 | unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req)); |
| 543 | struct aead_sg_list *sgl = &ctx->tsgl; |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 544 | struct aead_async_rsgl *last_rsgl = NULL; |
| 545 | struct aead_async_rsgl *rsgl, *tmp; |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 546 | int err = -EINVAL; |
| 547 | unsigned long used = 0; |
| 548 | size_t outlen = 0; |
| 549 | size_t usedpages = 0; |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Herbert Xu | 19fa775 | 2015-05-27 17:24:41 +0800 | [diff] [blame] | 588 | outlen = used; |
| 589 | |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 590 | /* |
| 591 | * The cipher operation input data is reduced by the associated data |
| 592 | * length as this data is processed separately later on. |
| 593 | */ |
Herbert Xu | 19fa775 | 2015-05-27 17:24:41 +0800 | [diff] [blame] | 594 | used -= ctx->aead_assoclen + (ctx->enc ? as : 0); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 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 | |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 613 | /* make one iovec available as scatterlist */ |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 614 | err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 615 | if (err < 0) |
| 616 | goto unlock; |
| 617 | usedpages += err; |
Tadeusz Struk | 7b2a18e | 2015-05-15 10:18:37 -0700 | [diff] [blame] | 618 | /* chain the new scatterlist with previous one */ |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 619 | if (last_rsgl) |
| 620 | af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl); |
| 621 | |
| 622 | last_rsgl = rsgl; |
Tadeusz Struk | 7b2a18e | 2015-05-15 10:18:37 -0700 | [diff] [blame] | 623 | |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 628 | } |
| 629 | |
| 630 | err = -EINVAL; |
| 631 | /* ensure output buffer is sufficiently large */ |
| 632 | if (usedpages < outlen) |
| 633 | goto unlock; |
| 634 | |
Herbert Xu | 19fa775 | 2015-05-27 17:24:41 +0800 | [diff] [blame] | 635 | sg_mark_end(sgl->sg + sgl->cur - 1); |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 636 | aead_request_set_crypt(&ctx->aead_req, sgl->sg, ctx->first_rsgl.sgl.sg, |
Herbert Xu | 19fa775 | 2015-05-27 17:24:41 +0800 | [diff] [blame] | 637 | used, ctx->iv); |
| 638 | aead_request_set_ad(&ctx->aead_req, ctx->aead_assoclen); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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); |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 649 | |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 650 | goto unlock; |
| 651 | } |
| 652 | |
| 653 | aead_put_sgl(sk); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 654 | err = 0; |
| 655 | |
| 656 | unlock: |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 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); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 664 | aead_wmem_wakeup(sk); |
| 665 | release_sock(sk); |
| 666 | |
| 667 | return err ? err : outlen; |
| 668 | } |
| 669 | |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 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 | |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | { |
Herbert Xu | 5e4b8c1 | 2015-08-13 17:29:06 +0800 | [diff] [blame] | 722 | return crypto_alloc_aead(name, type, mask); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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 | |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 747 | WARN_ON(atomic_read(&sk->sk_refcnt) != 0); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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); |
Tadeusz Struk | 83094e5e | 2016-03-11 11:50:33 -0800 | [diff] [blame] | 782 | INIT_LIST_HEAD(&ctx->list); |
Stephan Mueller | 400c40c | 2015-02-28 20:50:00 +0100 | [diff] [blame] | 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"); |