2 * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 /* Required for vmsplice */
18 #include <openssl/engine.h>
19 #include <openssl/async.h>
20 #include <openssl/err.h>
21 #include "internal/nelem.h"
23 #include <sys/socket.h>
24 #include <linux/version.h>
28 #if LINUX_VERSION_CODE < KERNEL_VERSION(K_MAJ, K_MIN1, K_MIN2) || \
31 # warning "AFALG ENGINE requires Kernel Headers >= 4.1.0"
32 # warning "Skipping Compilation of AFALG engine"
34 void engine_load_afalg_int(void);
35 void engine_load_afalg_int(void)
40 # include <linux/if_alg.h>
42 # include <sys/utsname.h>
44 # include <linux/aio_abi.h>
45 # include <sys/syscall.h>
49 # include "e_afalg_err.c"
56 # ifndef SPLICE_F_GIFT
57 # define SPLICE_F_GIFT (0x08)
61 # define ALG_AES_IV_LEN 16
62 # define ALG_IV_LEN(len) (sizeof(struct af_alg_iv) + (len))
63 # define ALG_OP_TYPE unsigned int
64 # define ALG_OP_LEN (sizeof(ALG_OP_TYPE))
66 #define ALG_MAX_SALG_NAME 64
67 #define ALG_MAX_SALG_TYPE 14
69 # ifdef OPENSSL_NO_DYNAMIC_ENGINE
70 void engine_load_afalg_int(void);
73 /* Local Linkage Functions */
74 static int afalg_init_aio(afalg_aio *aio);
75 static int afalg_fin_cipher_aio(afalg_aio *ptr, int sfd,
76 unsigned char *buf, size_t len);
77 static int afalg_create_sk(afalg_ctx *actx, const char *ciphertype,
78 const char *ciphername);
79 static int afalg_destroy(ENGINE *e);
80 static int afalg_init(ENGINE *e);
81 static int afalg_finish(ENGINE *e);
82 const EVP_CIPHER *afalg_aes_cbc(int nid);
83 static cbc_handles *get_cipher_handle(int nid);
84 static int afalg_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
85 const int **nids, int nid);
86 static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
87 const unsigned char *iv, int enc);
88 static int afalg_do_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
89 const unsigned char *in, size_t inl);
90 static int afalg_cipher_cleanup(EVP_CIPHER_CTX *ctx);
91 static int afalg_chk_platform(void);
93 /* Engine Id and Name */
94 static const char *engine_afalg_id = "afalg";
95 static const char *engine_afalg_name = "AFALG engine support";
97 static int afalg_cipher_nids[] = {
103 static cbc_handles cbc_handle[] = {{AES_KEY_SIZE_128, NULL},
104 {AES_KEY_SIZE_192, NULL},
105 {AES_KEY_SIZE_256, NULL}};
107 static ossl_inline int io_setup(unsigned n, aio_context_t *ctx)
109 return syscall(__NR_io_setup, n, ctx);
112 static ossl_inline int eventfd(int n)
114 return syscall(__NR_eventfd2, n, 0);
117 static ossl_inline int io_destroy(aio_context_t ctx)
119 return syscall(__NR_io_destroy, ctx);
122 static ossl_inline int io_read(aio_context_t ctx, long n, struct iocb **iocb)
124 return syscall(__NR_io_submit, ctx, n, iocb);
127 static ossl_inline int io_getevents(aio_context_t ctx, long min, long max,
128 struct io_event *events,
129 struct timespec *timeout)
131 return syscall(__NR_io_getevents, ctx, min, max, events, timeout);
134 static void afalg_waitfd_cleanup(ASYNC_WAIT_CTX *ctx, const void *key,
135 OSSL_ASYNC_FD waitfd, void *custom)
140 static int afalg_setup_async_event_notification(afalg_aio *aio)
143 ASYNC_WAIT_CTX *waitctx;
147 if ((job = ASYNC_get_current_job()) != NULL) {
149 waitctx = ASYNC_get_wait_ctx(job);
150 if (waitctx == NULL) {
151 ALG_WARN("%s: ASYNC_get_wait_ctx error", __func__);
154 /* Get waitfd from ASYNC_WAIT_CTX if it is already set */
155 ret = ASYNC_WAIT_CTX_get_fd(waitctx, engine_afalg_id,
159 * waitfd is not set in ASYNC_WAIT_CTX, create a new one
160 * and set it. efd will be signaled when AIO operation completes
162 aio->efd = eventfd(0);
163 if (aio->efd == -1) {
164 ALG_PERR("%s: Failed to get eventfd : ", __func__);
165 AFALGerr(AFALG_F_AFALG_SETUP_ASYNC_EVENT_NOTIFICATION,
166 AFALG_R_EVENTFD_FAILED);
169 ret = ASYNC_WAIT_CTX_set_wait_fd(waitctx, engine_afalg_id,
171 afalg_waitfd_cleanup);
173 ALG_WARN("%s: Failed to set wait fd", __func__);
177 /* make fd non-blocking in async mode */
178 if (fcntl(aio->efd, F_SETFL, O_NONBLOCK) != 0) {
179 ALG_WARN("%s: Failed to set event fd as NONBLOCKING",
183 aio->mode = MODE_ASYNC;
186 aio->efd = eventfd(0);
187 if (aio->efd == -1) {
188 ALG_PERR("%s: Failed to get eventfd : ", __func__);
189 AFALGerr(AFALG_F_AFALG_SETUP_ASYNC_EVENT_NOTIFICATION,
190 AFALG_R_EVENTFD_FAILED);
193 aio->mode = MODE_SYNC;
198 int afalg_init_aio(afalg_aio *aio)
202 /* Initialise for AIO */
204 r = io_setup(MAX_INFLIGHTS, &aio->aio_ctx);
206 ALG_PERR("%s: io_setup error : ", __func__);
207 AFALGerr(AFALG_F_AFALG_INIT_AIO, AFALG_R_IO_SETUP_FAILED);
211 memset(aio->cbt, 0, sizeof(aio->cbt));
213 aio->mode = MODE_UNINIT;
218 int afalg_fin_cipher_aio(afalg_aio *aio, int sfd, unsigned char *buf,
223 unsigned int done = 0;
225 struct timespec timeout;
226 struct io_event events[MAX_INFLIGHTS];
232 /* if efd has not been initialised yet do it here */
233 if (aio->mode == MODE_UNINIT) {
234 r = afalg_setup_async_event_notification(aio);
239 cb = &(aio->cbt[0 % MAX_INFLIGHTS]);
240 memset(cb, '\0', sizeof(*cb));
241 cb->aio_fildes = sfd;
242 cb->aio_lio_opcode = IOCB_CMD_PREAD;
244 * The pointer has to be converted to unsigned value first to avoid
245 * sign extension on cast to 64 bit value in 32-bit builds
247 cb->aio_buf = (size_t)buf;
250 cb->aio_nbytes = len;
251 cb->aio_flags = IOCB_FLAG_RESFD;
252 cb->aio_resfd = aio->efd;
255 * Perform AIO read on AFALG socket, this in turn performs an async
256 * crypto operation in kernel space
258 r = io_read(aio->aio_ctx, 1, &cb);
260 ALG_PWARN("%s: io_read failed : ", __func__);
265 /* While AIO read is being performed pause job */
268 /* Check for completion of AIO read */
269 r = read(aio->efd, &eval, sizeof(eval));
271 if (errno == EAGAIN || errno == EWOULDBLOCK)
273 ALG_PERR("%s: read failed for event fd : ", __func__);
275 } else if (r == 0 || eval <= 0) {
276 ALG_WARN("%s: eventfd read %d bytes, eval = %lu\n", __func__, r,
281 /* Get results of AIO read */
282 r = io_getevents(aio->aio_ctx, 1, MAX_INFLIGHTS,
286 * events.res indicates the actual status of the operation.
287 * Handle the error condition first.
289 if (events[0].res < 0) {
291 * Underlying operation cannot be completed at the time
292 * of previous submission. Resubmit for the operation.
294 if (events[0].res == -EBUSY && retry++ < 3) {
295 r = io_read(aio->aio_ctx, 1, &cb);
297 ALG_PERR("%s: retry %d for io_read failed : ",
304 * Retries exceed for -EBUSY or unrecoverable error
305 * condition for this instance of operation.
308 ("%s: Crypto Operation failed with code %lld\n",
309 __func__, events[0].res);
313 /* Operation successful. */
316 ALG_PERR("%s: io_getevents failed : ", __func__);
319 ALG_WARN("%s: io_geteventd read 0 bytes\n", __func__);
327 static ossl_inline void afalg_set_op_sk(struct cmsghdr *cmsg,
328 const ALG_OP_TYPE op)
330 cmsg->cmsg_level = SOL_ALG;
331 cmsg->cmsg_type = ALG_SET_OP;
332 cmsg->cmsg_len = CMSG_LEN(ALG_OP_LEN);
333 memcpy(CMSG_DATA(cmsg), &op, ALG_OP_LEN);
336 static void afalg_set_iv_sk(struct cmsghdr *cmsg, const unsigned char *iv,
337 const unsigned int len)
339 struct af_alg_iv *aiv;
341 cmsg->cmsg_level = SOL_ALG;
342 cmsg->cmsg_type = ALG_SET_IV;
343 cmsg->cmsg_len = CMSG_LEN(ALG_IV_LEN(len));
344 aiv = (struct af_alg_iv *)CMSG_DATA(cmsg);
346 memcpy(aiv->iv, iv, len);
349 static ossl_inline int afalg_set_key(afalg_ctx *actx, const unsigned char *key,
353 ret = setsockopt(actx->bfd, SOL_ALG, ALG_SET_KEY, key, klen);
355 ALG_PERR("%s: Failed to set socket option : ", __func__);
356 AFALGerr(AFALG_F_AFALG_SET_KEY, AFALG_R_SOCKET_SET_KEY_FAILED);
362 static int afalg_create_sk(afalg_ctx *actx, const char *ciphertype,
363 const char *ciphername)
365 struct sockaddr_alg sa;
368 actx->bfd = actx->sfd = -1;
370 memset(&sa, 0, sizeof(sa));
371 sa.salg_family = AF_ALG;
372 strncpy((char *) sa.salg_type, ciphertype, ALG_MAX_SALG_TYPE);
373 sa.salg_type[ALG_MAX_SALG_TYPE-1] = '\0';
374 strncpy((char *) sa.salg_name, ciphername, ALG_MAX_SALG_NAME);
375 sa.salg_name[ALG_MAX_SALG_NAME-1] = '\0';
377 actx->bfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
378 if (actx->bfd == -1) {
379 ALG_PERR("%s: Failed to open socket : ", __func__);
380 AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_CREATE_FAILED);
384 r = bind(actx->bfd, (struct sockaddr *)&sa, sizeof(sa));
386 ALG_PERR("%s: Failed to bind socket : ", __func__);
387 AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_BIND_FAILED);
391 actx->sfd = accept(actx->bfd, NULL, 0);
393 ALG_PERR("%s: Socket Accept Failed : ", __func__);
394 AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_ACCEPT_FAILED);
405 actx->bfd = actx->sfd = -1;
409 static int afalg_start_cipher_sk(afalg_ctx *actx, const unsigned char *in,
410 size_t inl, const unsigned char *iv,
413 struct msghdr msg = { 0 };
414 struct cmsghdr *cmsg;
417 # ifdef ALG_ZERO_COPY
420 char cbuf[CMSG_SPACE(ALG_IV_LEN(ALG_AES_IV_LEN)) + CMSG_SPACE(ALG_OP_LEN)];
422 memset(cbuf, 0, sizeof(cbuf));
423 msg.msg_control = cbuf;
424 msg.msg_controllen = sizeof(cbuf);
427 * cipher direction (i.e. encrypt or decrypt) and iv are sent to the
428 * kernel as part of sendmsg()'s ancillary data
430 cmsg = CMSG_FIRSTHDR(&msg);
431 afalg_set_op_sk(cmsg, enc);
432 cmsg = CMSG_NXTHDR(&msg, cmsg);
433 afalg_set_iv_sk(cmsg, iv, ALG_AES_IV_LEN);
435 /* iov that describes input data */
436 iov.iov_base = (unsigned char *)in;
439 msg.msg_flags = MSG_MORE;
441 # ifdef ALG_ZERO_COPY
444 * Works best when buffer is 4k aligned
445 * OPENS: out of place processing (i.e. out != in)
448 /* Input data is not sent as part of call to sendmsg() */
452 /* Sendmsg() sends iv and cipher direction to the kernel */
453 sbytes = sendmsg(actx->sfd, &msg, 0);
455 ALG_PERR("%s: sendmsg failed for zero copy cipher operation : ",
461 * vmsplice and splice are used to pin the user space input buffer for
462 * kernel space processing avoiding copys from user to kernel space
464 ret = vmsplice(actx->zc_pipe[1], &iov, 1, SPLICE_F_GIFT);
466 ALG_PERR("%s: vmsplice failed : ", __func__);
470 ret = splice(actx->zc_pipe[0], NULL, actx->sfd, NULL, inl, 0);
472 ALG_PERR("%s: splice failed : ", __func__);
479 /* Sendmsg() sends iv, cipher direction and input data to the kernel */
480 sbytes = sendmsg(actx->sfd, &msg, 0);
482 ALG_PERR("%s: sendmsg failed for cipher operation : ", __func__);
486 if (sbytes != (ssize_t) inl) {
487 ALG_WARN("Cipher operation send bytes %zd != inlen %zd\n", sbytes,
496 static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
497 const unsigned char *iv, int enc)
502 char ciphername[ALG_MAX_SALG_NAME];
504 if (ctx == NULL || key == NULL) {
505 ALG_WARN("%s: Null Parameter\n", __func__);
509 if (EVP_CIPHER_CTX_cipher(ctx) == NULL) {
510 ALG_WARN("%s: Cipher object NULL\n", __func__);
514 actx = EVP_CIPHER_CTX_get_cipher_data(ctx);
516 ALG_WARN("%s: Cipher data NULL\n", __func__);
520 ciphertype = EVP_CIPHER_CTX_nid(ctx);
521 switch (ciphertype) {
522 case NID_aes_128_cbc:
523 case NID_aes_192_cbc:
524 case NID_aes_256_cbc:
525 strncpy(ciphername, "cbc(aes)", ALG_MAX_SALG_NAME);
528 ALG_WARN("%s: Unsupported Cipher type %d\n", __func__, ciphertype);
531 ciphername[ALG_MAX_SALG_NAME-1]='\0';
533 if (ALG_AES_IV_LEN != EVP_CIPHER_CTX_iv_length(ctx)) {
534 ALG_WARN("%s: Unsupported IV length :%d\n", __func__,
535 EVP_CIPHER_CTX_iv_length(ctx));
539 /* Setup AFALG socket for crypto processing */
540 ret = afalg_create_sk(actx, "skcipher", ciphername);
545 ret = afalg_set_key(actx, key, EVP_CIPHER_CTX_key_length(ctx));
549 /* Setup AIO ctx to allow async AFALG crypto processing */
550 if (afalg_init_aio(&actx->aio) == 0)
553 # ifdef ALG_ZERO_COPY
557 actx->init_done = MAGIC_INIT_NUM;
567 static int afalg_do_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
568 const unsigned char *in, size_t inl)
572 char nxtiv[ALG_AES_IV_LEN] = { 0 };
574 if (ctx == NULL || out == NULL || in == NULL) {
575 ALG_WARN("NULL parameter passed to function %s\n", __func__);
579 actx = (afalg_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
580 if (actx == NULL || actx->init_done != MAGIC_INIT_NUM) {
581 ALG_WARN("%s afalg ctx passed\n",
582 ctx == NULL ? "NULL" : "Uninitialised");
587 * set iv now for decrypt operation as the input buffer can be
588 * overwritten for inplace operation where in = out.
590 if (EVP_CIPHER_CTX_encrypting(ctx) == 0) {
591 memcpy(nxtiv, in + (inl - ALG_AES_IV_LEN), ALG_AES_IV_LEN);
594 /* Send input data to kernel space */
595 ret = afalg_start_cipher_sk(actx, (unsigned char *)in, inl,
596 EVP_CIPHER_CTX_iv(ctx),
597 EVP_CIPHER_CTX_encrypting(ctx));
602 /* Perform async crypto operation in kernel space */
603 ret = afalg_fin_cipher_aio(&actx->aio, actx->sfd, out, inl);
607 if (EVP_CIPHER_CTX_encrypting(ctx)) {
608 memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), out + (inl - ALG_AES_IV_LEN),
611 memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), nxtiv, ALG_AES_IV_LEN);
617 static int afalg_cipher_cleanup(EVP_CIPHER_CTX *ctx)
622 ALG_WARN("NULL parameter passed to function %s\n", __func__);
626 actx = (afalg_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
627 if (actx == NULL || actx->init_done != MAGIC_INIT_NUM) {
628 ALG_WARN("%s afalg ctx passed\n",
629 ctx == NULL ? "NULL" : "Uninitialised");
635 # ifdef ALG_ZERO_COPY
636 close(actx->zc_pipe[0]);
637 close(actx->zc_pipe[1]);
639 /* close efd in sync mode, async mode is closed in afalg_waitfd_cleanup() */
640 if (actx->aio.mode == MODE_SYNC)
641 close(actx->aio.efd);
642 io_destroy(actx->aio.aio_ctx);
647 static cbc_handles *get_cipher_handle(int nid)
650 case NID_aes_128_cbc:
651 return &cbc_handle[AES_CBC_128];
652 case NID_aes_192_cbc:
653 return &cbc_handle[AES_CBC_192];
654 case NID_aes_256_cbc:
655 return &cbc_handle[AES_CBC_256];
661 const EVP_CIPHER *afalg_aes_cbc(int nid)
663 cbc_handles *cipher_handle = get_cipher_handle(nid);
664 if (cipher_handle->_hidden == NULL
665 && ((cipher_handle->_hidden =
666 EVP_CIPHER_meth_new(nid,
668 cipher_handle->key_size)) == NULL
669 || !EVP_CIPHER_meth_set_iv_length(cipher_handle->_hidden,
671 || !EVP_CIPHER_meth_set_flags(cipher_handle->_hidden,
673 EVP_CIPH_FLAG_DEFAULT_ASN1)
674 || !EVP_CIPHER_meth_set_init(cipher_handle->_hidden,
676 || !EVP_CIPHER_meth_set_do_cipher(cipher_handle->_hidden,
678 || !EVP_CIPHER_meth_set_cleanup(cipher_handle->_hidden,
679 afalg_cipher_cleanup)
680 || !EVP_CIPHER_meth_set_impl_ctx_size(cipher_handle->_hidden,
681 sizeof(afalg_ctx)))) {
682 EVP_CIPHER_meth_free(cipher_handle->_hidden);
683 cipher_handle->_hidden= NULL;
685 return cipher_handle->_hidden;
688 static int afalg_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
689 const int **nids, int nid)
693 if (cipher == NULL) {
694 *nids = afalg_cipher_nids;
695 return (sizeof(afalg_cipher_nids) / sizeof(afalg_cipher_nids[0]));
699 case NID_aes_128_cbc:
700 case NID_aes_192_cbc:
701 case NID_aes_256_cbc:
702 *cipher = afalg_aes_cbc(nid);
711 static int bind_afalg(ENGINE *e)
713 /* Ensure the afalg error handling is set up */
715 ERR_load_AFALG_strings();
717 if (!ENGINE_set_id(e, engine_afalg_id)
718 || !ENGINE_set_name(e, engine_afalg_name)
719 || !ENGINE_set_destroy_function(e, afalg_destroy)
720 || !ENGINE_set_init_function(e, afalg_init)
721 || !ENGINE_set_finish_function(e, afalg_finish)) {
722 AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
727 * Create _hidden_aes_xxx_cbc by calling afalg_aes_xxx_cbc
728 * now, as bind_aflag can only be called by one thread at a
731 for(i = 0; i < OSSL_NELEM(afalg_cipher_nids); i++) {
732 if (afalg_aes_cbc(afalg_cipher_nids[i]) == NULL) {
733 AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
738 if (!ENGINE_set_ciphers(e, afalg_ciphers)) {
739 AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
746 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
747 static int bind_helper(ENGINE *e, const char *id)
749 if (id && (strcmp(id, engine_afalg_id) != 0))
752 if (!afalg_chk_platform())
760 IMPLEMENT_DYNAMIC_CHECK_FN()
761 IMPLEMENT_DYNAMIC_BIND_FN(bind_helper)
764 static int afalg_chk_platform(void)
768 int kver[3] = { -1, -1, -1 };
775 AFALGerr(AFALG_F_AFALG_CHK_PLATFORM,
776 AFALG_R_FAILED_TO_GET_PLATFORM_INFO);
780 str = strtok(ut.release, ".");
781 for (i = 0; i < 3 && str != NULL; i++) {
783 str = strtok(NULL, ".");
786 if (KERNEL_VERSION(kver[0], kver[1], kver[2])
787 < KERNEL_VERSION(K_MAJ, K_MIN1, K_MIN2)) {
788 ALG_ERR("ASYNC AFALG not supported this kernel(%d.%d.%d)\n",
789 kver[0], kver[1], kver[2]);
790 ALG_ERR("ASYNC AFALG requires kernel version %d.%d.%d or later\n",
791 K_MAJ, K_MIN1, K_MIN2);
792 AFALGerr(AFALG_F_AFALG_CHK_PLATFORM,
793 AFALG_R_KERNEL_DOES_NOT_SUPPORT_ASYNC_AFALG);
797 /* Test if we can actually create an AF_ALG socket */
798 sock = socket(AF_ALG, SOCK_SEQPACKET, 0);
800 AFALGerr(AFALG_F_AFALG_CHK_PLATFORM, AFALG_R_SOCKET_CREATE_FAILED);
808 # ifdef OPENSSL_NO_DYNAMIC_ENGINE
809 static ENGINE *engine_afalg(void)
811 ENGINE *ret = ENGINE_new();
814 if (!bind_afalg(ret)) {
821 void engine_load_afalg_int(void)
825 if (!afalg_chk_platform())
828 toadd = engine_afalg();
837 static int afalg_init(ENGINE *e)
842 static int afalg_finish(ENGINE *e)
847 static int free_cbc(void)
849 short unsigned int i;
850 for(i = 0; i < OSSL_NELEM(afalg_cipher_nids); i++) {
851 EVP_CIPHER_meth_free(cbc_handle[i]._hidden);
852 cbc_handle[i]._hidden = NULL;
857 static int afalg_destroy(ENGINE *e)
859 ERR_unload_AFALG_strings();
864 #endif /* KERNEL VERSION */