xref: /freebsd/crypto/openssl/engines/e_afalg.c (revision 1da7787f71f19e32f5123904324c67a564a950cd)
1 /*
2  * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
3  *
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
8  */
9 
10 /* Required for vmsplice */
11 #ifndef _GNU_SOURCE
12 # define _GNU_SOURCE
13 #endif
14 #include <stdio.h>
15 #include <string.h>
16 #include <unistd.h>
17 
18 #include <openssl/engine.h>
19 #include <openssl/async.h>
20 #include <openssl/err.h>
21 #include "internal/nelem.h"
22 
23 #include <sys/socket.h>
24 #include <linux/version.h>
25 #define K_MAJ   4
26 #define K_MIN1  1
27 #define K_MIN2  0
28 #if LINUX_VERSION_CODE < KERNEL_VERSION(K_MAJ, K_MIN1, K_MIN2) || \
29     !defined(AF_ALG)
30 # ifndef PEDANTIC
31 #  warning "AFALG ENGINE requires Kernel Headers >= 4.1.0"
32 #  warning "Skipping Compilation of AFALG engine"
33 # endif
34 void engine_load_afalg_int(void);
35 void engine_load_afalg_int(void)
36 {
37 }
38 #else
39 
40 # include <linux/if_alg.h>
41 # include <fcntl.h>
42 # include <sys/utsname.h>
43 
44 # include <linux/aio_abi.h>
45 # include <sys/syscall.h>
46 # include <errno.h>
47 
48 # include "e_afalg.h"
49 # include "e_afalg_err.c"
50 
51 # ifndef SOL_ALG
52 #  define SOL_ALG 279
53 # endif
54 
55 # ifdef ALG_ZERO_COPY
56 #  ifndef SPLICE_F_GIFT
57 #   define SPLICE_F_GIFT    (0x08)
58 #  endif
59 # endif
60 
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))
65 
66 #define ALG_MAX_SALG_NAME       64
67 #define ALG_MAX_SALG_TYPE       14
68 
69 # ifdef OPENSSL_NO_DYNAMIC_ENGINE
70 void engine_load_afalg_int(void);
71 # endif
72 
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 static 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);
92 
93 /* Engine Id and Name */
94 static const char *engine_afalg_id = "afalg";
95 static const char *engine_afalg_name = "AFALG engine support";
96 
97 static int afalg_cipher_nids[] = {
98     NID_aes_128_cbc,
99     NID_aes_192_cbc,
100     NID_aes_256_cbc,
101 };
102 
103 static cbc_handles cbc_handle[] = {{AES_KEY_SIZE_128, NULL},
104                                     {AES_KEY_SIZE_192, NULL},
105                                     {AES_KEY_SIZE_256, NULL}};
106 
107 static ossl_inline int io_setup(unsigned n, aio_context_t *ctx)
108 {
109     return syscall(__NR_io_setup, n, ctx);
110 }
111 
112 static ossl_inline int eventfd(int n)
113 {
114     return syscall(__NR_eventfd2, n, 0);
115 }
116 
117 static ossl_inline int io_destroy(aio_context_t ctx)
118 {
119     return syscall(__NR_io_destroy, ctx);
120 }
121 
122 static ossl_inline int io_read(aio_context_t ctx, long n, struct iocb **iocb)
123 {
124     return syscall(__NR_io_submit, ctx, n, iocb);
125 }
126 
127 static ossl_inline int io_getevents(aio_context_t ctx, long min, long max,
128                                struct io_event *events,
129                                struct timespec *timeout)
130 {
131     return syscall(__NR_io_getevents, ctx, min, max, events, timeout);
132 }
133 
134 static void afalg_waitfd_cleanup(ASYNC_WAIT_CTX *ctx, const void *key,
135                                  OSSL_ASYNC_FD waitfd, void *custom)
136 {
137     close(waitfd);
138 }
139 
140 static int afalg_setup_async_event_notification(afalg_aio *aio)
141 {
142     ASYNC_JOB *job;
143     ASYNC_WAIT_CTX *waitctx;
144     void *custom = NULL;
145     int ret;
146 
147     if ((job = ASYNC_get_current_job()) != NULL) {
148         /* Async mode */
149         waitctx = ASYNC_get_wait_ctx(job);
150         if (waitctx == NULL) {
151             ALG_WARN("%s(%d): ASYNC_get_wait_ctx error", __FILE__, __LINE__);
152             return 0;
153         }
154         /* Get waitfd from ASYNC_WAIT_CTX if it is already set */
155         ret = ASYNC_WAIT_CTX_get_fd(waitctx, engine_afalg_id,
156                                     &aio->efd, &custom);
157         if (ret == 0) {
158             /*
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
161              */
162             aio->efd = eventfd(0);
163             if (aio->efd == -1) {
164                 ALG_PERR("%s(%d): Failed to get eventfd : ", __FILE__,
165                          __LINE__);
166                 AFALGerr(AFALG_F_AFALG_SETUP_ASYNC_EVENT_NOTIFICATION,
167                          AFALG_R_EVENTFD_FAILED);
168                 return 0;
169             }
170             ret = ASYNC_WAIT_CTX_set_wait_fd(waitctx, engine_afalg_id,
171                                              aio->efd, custom,
172                                              afalg_waitfd_cleanup);
173             if (ret == 0) {
174                 ALG_WARN("%s(%d): Failed to set wait fd", __FILE__, __LINE__);
175                 close(aio->efd);
176                 return 0;
177             }
178             /* make fd non-blocking in async mode */
179             if (fcntl(aio->efd, F_SETFL, O_NONBLOCK) != 0) {
180                 ALG_WARN("%s(%d): Failed to set event fd as NONBLOCKING",
181                          __FILE__, __LINE__);
182             }
183         }
184         aio->mode = MODE_ASYNC;
185     } else {
186         /* Sync mode */
187         aio->efd = eventfd(0);
188         if (aio->efd == -1) {
189             ALG_PERR("%s(%d): Failed to get eventfd : ", __FILE__, __LINE__);
190             AFALGerr(AFALG_F_AFALG_SETUP_ASYNC_EVENT_NOTIFICATION,
191                      AFALG_R_EVENTFD_FAILED);
192             return 0;
193         }
194         aio->mode = MODE_SYNC;
195     }
196     return 1;
197 }
198 
199 static int afalg_init_aio(afalg_aio *aio)
200 {
201     int r = -1;
202 
203     /* Initialise for AIO */
204     aio->aio_ctx = 0;
205     r = io_setup(MAX_INFLIGHTS, &aio->aio_ctx);
206     if (r < 0) {
207         ALG_PERR("%s(%d): io_setup error : ", __FILE__, __LINE__);
208         AFALGerr(AFALG_F_AFALG_INIT_AIO, AFALG_R_IO_SETUP_FAILED);
209         return 0;
210     }
211 
212     memset(aio->cbt, 0, sizeof(aio->cbt));
213     aio->efd = -1;
214     aio->mode = MODE_UNINIT;
215 
216     return 1;
217 }
218 
219 static int afalg_fin_cipher_aio(afalg_aio *aio, int sfd, unsigned char *buf,
220                                 size_t len)
221 {
222     int r;
223     int retry = 0;
224     unsigned int done = 0;
225     struct iocb *cb;
226     struct timespec timeout;
227     struct io_event events[MAX_INFLIGHTS];
228     u_int64_t eval = 0;
229 
230     timeout.tv_sec = 0;
231     timeout.tv_nsec = 0;
232 
233     /* if efd has not been initialised yet do it here */
234     if (aio->mode == MODE_UNINIT) {
235         r = afalg_setup_async_event_notification(aio);
236         if (r == 0)
237             return 0;
238     }
239 
240     cb = &(aio->cbt[0 % MAX_INFLIGHTS]);
241     memset(cb, '\0', sizeof(*cb));
242     cb->aio_fildes = sfd;
243     cb->aio_lio_opcode = IOCB_CMD_PREAD;
244     /*
245      * The pointer has to be converted to unsigned value first to avoid
246      * sign extension on cast to 64 bit value in 32-bit builds
247      */
248     cb->aio_buf = (size_t)buf;
249     cb->aio_offset = 0;
250     cb->aio_data = 0;
251     cb->aio_nbytes = len;
252     cb->aio_flags = IOCB_FLAG_RESFD;
253     cb->aio_resfd = aio->efd;
254 
255     /*
256      * Perform AIO read on AFALG socket, this in turn performs an async
257      * crypto operation in kernel space
258      */
259     r = io_read(aio->aio_ctx, 1, &cb);
260     if (r < 0) {
261         ALG_PWARN("%s(%d): io_read failed : ", __FILE__, __LINE__);
262         return 0;
263     }
264 
265     do {
266         /* While AIO read is being performed pause job */
267         ASYNC_pause_job();
268 
269         /* Check for completion of AIO read */
270         r = read(aio->efd, &eval, sizeof(eval));
271         if (r < 0) {
272             if (errno == EAGAIN || errno == EWOULDBLOCK)
273                 continue;
274             ALG_PERR("%s(%d): read failed for event fd : ", __FILE__, __LINE__);
275             return 0;
276         } else if (r == 0 || eval <= 0) {
277             ALG_WARN("%s(%d): eventfd read %d bytes, eval = %lu\n", __FILE__,
278                      __LINE__, r, eval);
279         }
280         if (eval > 0) {
281 
282             /* Get results of AIO read */
283             r = io_getevents(aio->aio_ctx, 1, MAX_INFLIGHTS,
284                              events, &timeout);
285             if (r > 0) {
286                 /*
287                  * events.res indicates the actual status of the operation.
288                  * Handle the error condition first.
289                  */
290                 if (events[0].res < 0) {
291                     /*
292                      * Underlying operation cannot be completed at the time
293                      * of previous submission. Resubmit for the operation.
294                      */
295                     if (events[0].res == -EBUSY && retry++ < 3) {
296                         r = io_read(aio->aio_ctx, 1, &cb);
297                         if (r < 0) {
298                             ALG_PERR("%s(%d): retry %d for io_read failed : ",
299                                      __FILE__, __LINE__, retry);
300                             return 0;
301                         }
302                         continue;
303                     } else {
304                         /*
305                          * Retries exceed for -EBUSY or unrecoverable error
306                          * condition for this instance of operation.
307                          */
308                         ALG_WARN
309                             ("%s(%d): Crypto Operation failed with code %lld\n",
310                              __FILE__, __LINE__, events[0].res);
311                         return 0;
312                     }
313                 }
314                 /* Operation successful. */
315                 done = 1;
316             } else if (r < 0) {
317                 ALG_PERR("%s(%d): io_getevents failed : ", __FILE__, __LINE__);
318                 return 0;
319             } else {
320                 ALG_WARN("%s(%d): io_geteventd read 0 bytes\n", __FILE__,
321                          __LINE__);
322             }
323         }
324     } while (!done);
325 
326     return 1;
327 }
328 
329 static ossl_inline void afalg_set_op_sk(struct cmsghdr *cmsg,
330                                    const ALG_OP_TYPE op)
331 {
332     cmsg->cmsg_level = SOL_ALG;
333     cmsg->cmsg_type = ALG_SET_OP;
334     cmsg->cmsg_len = CMSG_LEN(ALG_OP_LEN);
335     memcpy(CMSG_DATA(cmsg), &op, ALG_OP_LEN);
336 }
337 
338 static void afalg_set_iv_sk(struct cmsghdr *cmsg, const unsigned char *iv,
339                             const unsigned int len)
340 {
341     struct af_alg_iv *aiv;
342 
343     cmsg->cmsg_level = SOL_ALG;
344     cmsg->cmsg_type = ALG_SET_IV;
345     cmsg->cmsg_len = CMSG_LEN(ALG_IV_LEN(len));
346     aiv = (struct af_alg_iv *)CMSG_DATA(cmsg);
347     aiv->ivlen = len;
348     memcpy(aiv->iv, iv, len);
349 }
350 
351 static ossl_inline int afalg_set_key(afalg_ctx *actx, const unsigned char *key,
352                                 const int klen)
353 {
354     int ret;
355     ret = setsockopt(actx->bfd, SOL_ALG, ALG_SET_KEY, key, klen);
356     if (ret < 0) {
357         ALG_PERR("%s(%d): Failed to set socket option : ", __FILE__, __LINE__);
358         AFALGerr(AFALG_F_AFALG_SET_KEY, AFALG_R_SOCKET_SET_KEY_FAILED);
359         return 0;
360     }
361     return 1;
362 }
363 
364 static int afalg_create_sk(afalg_ctx *actx, const char *ciphertype,
365                                 const char *ciphername)
366 {
367     struct sockaddr_alg sa;
368     int r = -1;
369 
370     actx->bfd = actx->sfd = -1;
371 
372     memset(&sa, 0, sizeof(sa));
373     sa.salg_family = AF_ALG;
374     strncpy((char *) sa.salg_type, ciphertype, ALG_MAX_SALG_TYPE);
375     sa.salg_type[ALG_MAX_SALG_TYPE-1] = '\0';
376     strncpy((char *) sa.salg_name, ciphername, ALG_MAX_SALG_NAME);
377     sa.salg_name[ALG_MAX_SALG_NAME-1] = '\0';
378 
379     actx->bfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
380     if (actx->bfd == -1) {
381         ALG_PERR("%s(%d): Failed to open socket : ", __FILE__, __LINE__);
382         AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_CREATE_FAILED);
383         goto err;
384     }
385 
386     r = bind(actx->bfd, (struct sockaddr *)&sa, sizeof(sa));
387     if (r < 0) {
388         ALG_PERR("%s(%d): Failed to bind socket : ", __FILE__, __LINE__);
389         AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_BIND_FAILED);
390         goto err;
391     }
392 
393     actx->sfd = accept(actx->bfd, NULL, 0);
394     if (actx->sfd < 0) {
395         ALG_PERR("%s(%d): Socket Accept Failed : ", __FILE__, __LINE__);
396         AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_ACCEPT_FAILED);
397         goto err;
398     }
399 
400     return 1;
401 
402  err:
403     if (actx->bfd >= 0)
404         close(actx->bfd);
405     if (actx->sfd >= 0)
406         close(actx->sfd);
407     actx->bfd = actx->sfd = -1;
408     return 0;
409 }
410 
411 static int afalg_start_cipher_sk(afalg_ctx *actx, const unsigned char *in,
412                                  size_t inl, const unsigned char *iv,
413                                  unsigned int enc)
414 {
415     struct msghdr msg = { 0 };
416     struct cmsghdr *cmsg;
417     struct iovec iov;
418     ssize_t sbytes;
419 # ifdef ALG_ZERO_COPY
420     int ret;
421 # endif
422     char cbuf[CMSG_SPACE(ALG_IV_LEN(ALG_AES_IV_LEN)) + CMSG_SPACE(ALG_OP_LEN)];
423 
424     memset(cbuf, 0, sizeof(cbuf));
425     msg.msg_control = cbuf;
426     msg.msg_controllen = sizeof(cbuf);
427 
428     /*
429      * cipher direction (i.e. encrypt or decrypt) and iv are sent to the
430      * kernel as part of sendmsg()'s ancillary data
431      */
432     cmsg = CMSG_FIRSTHDR(&msg);
433     afalg_set_op_sk(cmsg, enc);
434     cmsg = CMSG_NXTHDR(&msg, cmsg);
435     afalg_set_iv_sk(cmsg, iv, ALG_AES_IV_LEN);
436 
437     /* iov that describes input data */
438     iov.iov_base = (unsigned char *)in;
439     iov.iov_len = inl;
440 
441     msg.msg_flags = MSG_MORE;
442 
443 # ifdef ALG_ZERO_COPY
444     /*
445      * ZERO_COPY mode
446      * Works best when buffer is 4k aligned
447      * OPENS: out of place processing (i.e. out != in)
448      */
449 
450     /* Input data is not sent as part of call to sendmsg() */
451     msg.msg_iovlen = 0;
452     msg.msg_iov = NULL;
453 
454     /* Sendmsg() sends iv and cipher direction to the kernel */
455     sbytes = sendmsg(actx->sfd, &msg, 0);
456     if (sbytes < 0) {
457         ALG_PERR("%s(%d): sendmsg failed for zero copy cipher operation : ",
458                  __FILE__, __LINE__);
459         return 0;
460     }
461 
462     /*
463      * vmsplice and splice are used to pin the user space input buffer for
464      * kernel space processing avoiding copys from user to kernel space
465      */
466     ret = vmsplice(actx->zc_pipe[1], &iov, 1, SPLICE_F_GIFT);
467     if (ret < 0) {
468         ALG_PERR("%s(%d): vmsplice failed : ", __FILE__, __LINE__);
469         return 0;
470     }
471 
472     ret = splice(actx->zc_pipe[0], NULL, actx->sfd, NULL, inl, 0);
473     if (ret < 0) {
474         ALG_PERR("%s(%d): splice failed : ", __FILE__, __LINE__);
475         return 0;
476     }
477 # else
478     msg.msg_iovlen = 1;
479     msg.msg_iov = &iov;
480 
481     /* Sendmsg() sends iv, cipher direction and input data to the kernel */
482     sbytes = sendmsg(actx->sfd, &msg, 0);
483     if (sbytes < 0) {
484         ALG_PERR("%s(%d): sendmsg failed for cipher operation : ", __FILE__,
485                  __LINE__);
486         return 0;
487     }
488 
489     if (sbytes != (ssize_t) inl) {
490         ALG_WARN("Cipher operation send bytes %zd != inlen %zd\n", sbytes,
491                 inl);
492         return 0;
493     }
494 # endif
495 
496     return 1;
497 }
498 
499 static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
500                              const unsigned char *iv, int enc)
501 {
502     int ciphertype;
503     int ret;
504     afalg_ctx *actx;
505     char ciphername[ALG_MAX_SALG_NAME];
506 
507     if (ctx == NULL || key == NULL) {
508         ALG_WARN("%s(%d): Null Parameter\n", __FILE__, __LINE__);
509         return 0;
510     }
511 
512     if (EVP_CIPHER_CTX_cipher(ctx) == NULL) {
513         ALG_WARN("%s(%d): Cipher object NULL\n", __FILE__, __LINE__);
514         return 0;
515     }
516 
517     actx = EVP_CIPHER_CTX_get_cipher_data(ctx);
518     if (actx == NULL) {
519         ALG_WARN("%s(%d): Cipher data NULL\n", __FILE__, __LINE__);
520         return 0;
521     }
522 
523     ciphertype = EVP_CIPHER_CTX_nid(ctx);
524     switch (ciphertype) {
525     case NID_aes_128_cbc:
526     case NID_aes_192_cbc:
527     case NID_aes_256_cbc:
528         strncpy(ciphername, "cbc(aes)", ALG_MAX_SALG_NAME);
529         break;
530     default:
531         ALG_WARN("%s(%d): Unsupported Cipher type %d\n", __FILE__, __LINE__,
532                  ciphertype);
533         return 0;
534     }
535     ciphername[ALG_MAX_SALG_NAME-1]='\0';
536 
537     if (ALG_AES_IV_LEN != EVP_CIPHER_CTX_iv_length(ctx)) {
538         ALG_WARN("%s(%d): Unsupported IV length :%d\n", __FILE__, __LINE__,
539                  EVP_CIPHER_CTX_iv_length(ctx));
540         return 0;
541     }
542 
543     /* Setup AFALG socket for crypto processing */
544     ret = afalg_create_sk(actx, "skcipher", ciphername);
545     if (ret < 1)
546         return 0;
547 
548 
549     ret = afalg_set_key(actx, key, EVP_CIPHER_CTX_key_length(ctx));
550     if (ret < 1)
551         goto err;
552 
553     /* Setup AIO ctx to allow async AFALG crypto processing */
554     if (afalg_init_aio(&actx->aio) == 0)
555         goto err;
556 
557 # ifdef ALG_ZERO_COPY
558     pipe(actx->zc_pipe);
559 # endif
560 
561     actx->init_done = MAGIC_INIT_NUM;
562 
563     return 1;
564 
565 err:
566     close(actx->sfd);
567     close(actx->bfd);
568     return 0;
569 }
570 
571 static int afalg_do_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
572                            const unsigned char *in, size_t inl)
573 {
574     afalg_ctx *actx;
575     int ret;
576     char nxtiv[ALG_AES_IV_LEN] = { 0 };
577 
578     if (ctx == NULL || out == NULL || in == NULL) {
579         ALG_WARN("NULL parameter passed to function %s(%d)\n", __FILE__,
580                  __LINE__);
581         return 0;
582     }
583 
584     actx = (afalg_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
585     if (actx == NULL || actx->init_done != MAGIC_INIT_NUM) {
586         ALG_WARN("%s afalg ctx passed\n",
587                  ctx == NULL ? "NULL" : "Uninitialised");
588         return 0;
589     }
590 
591     /*
592      * set iv now for decrypt operation as the input buffer can be
593      * overwritten for inplace operation where in = out.
594      */
595     if (EVP_CIPHER_CTX_encrypting(ctx) == 0) {
596         memcpy(nxtiv, in + (inl - ALG_AES_IV_LEN), ALG_AES_IV_LEN);
597     }
598 
599     /* Send input data to kernel space */
600     ret = afalg_start_cipher_sk(actx, (unsigned char *)in, inl,
601                                 EVP_CIPHER_CTX_iv(ctx),
602                                 EVP_CIPHER_CTX_encrypting(ctx));
603     if (ret < 1) {
604         return 0;
605     }
606 
607     /* Perform async crypto operation in kernel space */
608     ret = afalg_fin_cipher_aio(&actx->aio, actx->sfd, out, inl);
609     if (ret < 1)
610         return 0;
611 
612     if (EVP_CIPHER_CTX_encrypting(ctx)) {
613         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), out + (inl - ALG_AES_IV_LEN),
614                ALG_AES_IV_LEN);
615     } else {
616         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), nxtiv, ALG_AES_IV_LEN);
617     }
618 
619     return 1;
620 }
621 
622 static int afalg_cipher_cleanup(EVP_CIPHER_CTX *ctx)
623 {
624     afalg_ctx *actx;
625 
626     if (ctx == NULL) {
627         ALG_WARN("NULL parameter passed to function %s(%d)\n", __FILE__,
628                  __LINE__);
629         return 0;
630     }
631 
632     actx = (afalg_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
633     if (actx == NULL || actx->init_done != MAGIC_INIT_NUM) {
634         ALG_WARN("%s afalg ctx passed\n",
635                  ctx == NULL ? "NULL" : "Uninitialised");
636         return 0;
637     }
638 
639     close(actx->sfd);
640     close(actx->bfd);
641 # ifdef ALG_ZERO_COPY
642     close(actx->zc_pipe[0]);
643     close(actx->zc_pipe[1]);
644 # endif
645     /* close efd in sync mode, async mode is closed in afalg_waitfd_cleanup() */
646     if (actx->aio.mode == MODE_SYNC)
647         close(actx->aio.efd);
648     io_destroy(actx->aio.aio_ctx);
649 
650     return 1;
651 }
652 
653 static cbc_handles *get_cipher_handle(int nid)
654 {
655     switch (nid) {
656     case NID_aes_128_cbc:
657         return &cbc_handle[AES_CBC_128];
658     case NID_aes_192_cbc:
659         return &cbc_handle[AES_CBC_192];
660     case NID_aes_256_cbc:
661         return &cbc_handle[AES_CBC_256];
662     default:
663         return NULL;
664     }
665 }
666 
667 static const EVP_CIPHER *afalg_aes_cbc(int nid)
668 {
669     cbc_handles *cipher_handle = get_cipher_handle(nid);
670     if (cipher_handle->_hidden == NULL
671         && ((cipher_handle->_hidden =
672          EVP_CIPHER_meth_new(nid,
673                              AES_BLOCK_SIZE,
674                              cipher_handle->key_size)) == NULL
675         || !EVP_CIPHER_meth_set_iv_length(cipher_handle->_hidden,
676                                           AES_IV_LEN)
677         || !EVP_CIPHER_meth_set_flags(cipher_handle->_hidden,
678                                       EVP_CIPH_CBC_MODE |
679                                       EVP_CIPH_FLAG_DEFAULT_ASN1)
680         || !EVP_CIPHER_meth_set_init(cipher_handle->_hidden,
681                                      afalg_cipher_init)
682         || !EVP_CIPHER_meth_set_do_cipher(cipher_handle->_hidden,
683                                           afalg_do_cipher)
684         || !EVP_CIPHER_meth_set_cleanup(cipher_handle->_hidden,
685                                         afalg_cipher_cleanup)
686         || !EVP_CIPHER_meth_set_impl_ctx_size(cipher_handle->_hidden,
687                                               sizeof(afalg_ctx)))) {
688         EVP_CIPHER_meth_free(cipher_handle->_hidden);
689         cipher_handle->_hidden= NULL;
690     }
691     return cipher_handle->_hidden;
692 }
693 
694 static int afalg_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
695                          const int **nids, int nid)
696 {
697     int r = 1;
698 
699     if (cipher == NULL) {
700         *nids = afalg_cipher_nids;
701         return (sizeof(afalg_cipher_nids) / sizeof(afalg_cipher_nids[0]));
702     }
703 
704     switch (nid) {
705     case NID_aes_128_cbc:
706     case NID_aes_192_cbc:
707     case NID_aes_256_cbc:
708         *cipher = afalg_aes_cbc(nid);
709         break;
710     default:
711         *cipher = NULL;
712         r = 0;
713     }
714     return r;
715 }
716 
717 static int bind_afalg(ENGINE *e)
718 {
719     /* Ensure the afalg error handling is set up */
720     unsigned short i;
721     ERR_load_AFALG_strings();
722 
723     if (!ENGINE_set_id(e, engine_afalg_id)
724         || !ENGINE_set_name(e, engine_afalg_name)
725         || !ENGINE_set_destroy_function(e, afalg_destroy)
726         || !ENGINE_set_init_function(e, afalg_init)
727         || !ENGINE_set_finish_function(e, afalg_finish)) {
728         AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
729         return 0;
730     }
731 
732     /*
733      * Create _hidden_aes_xxx_cbc by calling afalg_aes_xxx_cbc
734      * now, as bind_aflag can only be called by one thread at a
735      * time.
736      */
737     for(i = 0; i < OSSL_NELEM(afalg_cipher_nids); i++) {
738         if (afalg_aes_cbc(afalg_cipher_nids[i]) == NULL) {
739             AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
740             return 0;
741         }
742     }
743 
744     if (!ENGINE_set_ciphers(e, afalg_ciphers)) {
745         AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
746         return 0;
747     }
748 
749     return 1;
750 }
751 
752 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
753 static int bind_helper(ENGINE *e, const char *id)
754 {
755     if (id && (strcmp(id, engine_afalg_id) != 0))
756         return 0;
757 
758     if (!afalg_chk_platform())
759         return 0;
760 
761     if (!bind_afalg(e))
762         return 0;
763     return 1;
764 }
765 
766 IMPLEMENT_DYNAMIC_CHECK_FN()
767     IMPLEMENT_DYNAMIC_BIND_FN(bind_helper)
768 # endif
769 
770 static int afalg_chk_platform(void)
771 {
772     int ret;
773     int i;
774     int kver[3] = { -1, -1, -1 };
775     int sock;
776     char *str;
777     struct utsname ut;
778 
779     ret = uname(&ut);
780     if (ret != 0) {
781         AFALGerr(AFALG_F_AFALG_CHK_PLATFORM,
782                  AFALG_R_FAILED_TO_GET_PLATFORM_INFO);
783         return 0;
784     }
785 
786     str = strtok(ut.release, ".");
787     for (i = 0; i < 3 && str != NULL; i++) {
788         kver[i] = atoi(str);
789         str = strtok(NULL, ".");
790     }
791 
792     if (KERNEL_VERSION(kver[0], kver[1], kver[2])
793         < KERNEL_VERSION(K_MAJ, K_MIN1, K_MIN2)) {
794         ALG_ERR("ASYNC AFALG not supported this kernel(%d.%d.%d)\n",
795                  kver[0], kver[1], kver[2]);
796         ALG_ERR("ASYNC AFALG requires kernel version %d.%d.%d or later\n",
797                  K_MAJ, K_MIN1, K_MIN2);
798         AFALGerr(AFALG_F_AFALG_CHK_PLATFORM,
799                  AFALG_R_KERNEL_DOES_NOT_SUPPORT_ASYNC_AFALG);
800         return 0;
801     }
802 
803     /* Test if we can actually create an AF_ALG socket */
804     sock = socket(AF_ALG, SOCK_SEQPACKET, 0);
805     if (sock == -1) {
806         AFALGerr(AFALG_F_AFALG_CHK_PLATFORM, AFALG_R_SOCKET_CREATE_FAILED);
807         return 0;
808     }
809     close(sock);
810 
811     return 1;
812 }
813 
814 # ifdef OPENSSL_NO_DYNAMIC_ENGINE
815 static ENGINE *engine_afalg(void)
816 {
817     ENGINE *ret = ENGINE_new();
818     if (ret == NULL)
819         return NULL;
820     if (!bind_afalg(ret)) {
821         ENGINE_free(ret);
822         return NULL;
823     }
824     return ret;
825 }
826 
827 void engine_load_afalg_int(void)
828 {
829     ENGINE *toadd;
830 
831     if (!afalg_chk_platform())
832         return;
833 
834     toadd = engine_afalg();
835     if (toadd == NULL)
836         return;
837     ENGINE_add(toadd);
838     ENGINE_free(toadd);
839     ERR_clear_error();
840 }
841 # endif
842 
843 static int afalg_init(ENGINE *e)
844 {
845     return 1;
846 }
847 
848 static int afalg_finish(ENGINE *e)
849 {
850     return 1;
851 }
852 
853 static int free_cbc(void)
854 {
855     short unsigned int i;
856     for(i = 0; i < OSSL_NELEM(afalg_cipher_nids); i++) {
857         EVP_CIPHER_meth_free(cbc_handle[i]._hidden);
858         cbc_handle[i]._hidden = NULL;
859     }
860     return 1;
861 }
862 
863 static int afalg_destroy(ENGINE *e)
864 {
865     ERR_unload_AFALG_strings();
866     free_cbc();
867     return 1;
868 }
869 
870 #endif                          /* KERNEL VERSION */
871