xref: /freebsd/crypto/openssl/engines/e_afalg.c (revision 5e3190f700637fcfc1a52daeaa4a031fdd2557c7)
1 /*
2  * Copyright 2016-2021 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (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 /* We need to use some deprecated APIs */
11 #define OPENSSL_SUPPRESS_DEPRECATED
12 
13 /* Required for vmsplice */
14 #ifndef _GNU_SOURCE
15 # define _GNU_SOURCE
16 #endif
17 #include <stdio.h>
18 #include <string.h>
19 #include <unistd.h>
20 
21 #include <openssl/engine.h>
22 #include <openssl/async.h>
23 #include <openssl/err.h>
24 #include "internal/nelem.h"
25 
26 #include <sys/socket.h>
27 #include <linux/version.h>
28 #define K_MAJ   4
29 #define K_MIN1  1
30 #define K_MIN2  0
31 #if LINUX_VERSION_CODE < KERNEL_VERSION(K_MAJ, K_MIN1, K_MIN2) || \
32     !defined(AF_ALG)
33 # ifndef PEDANTIC
34 #  warning "AFALG ENGINE requires Kernel Headers >= 4.1.0"
35 #  warning "Skipping Compilation of AFALG engine"
36 # endif
37 void engine_load_afalg_int(void);
38 void engine_load_afalg_int(void)
39 {
40 }
41 #else
42 
43 # include <linux/if_alg.h>
44 # include <fcntl.h>
45 # include <sys/utsname.h>
46 
47 # include <linux/aio_abi.h>
48 # include <sys/syscall.h>
49 # include <errno.h>
50 
51 # include "e_afalg.h"
52 # include "e_afalg_err.c"
53 
54 # ifndef SOL_ALG
55 #  define SOL_ALG 279
56 # endif
57 
58 # ifdef ALG_ZERO_COPY
59 #  ifndef SPLICE_F_GIFT
60 #   define SPLICE_F_GIFT    (0x08)
61 #  endif
62 # endif
63 
64 # define ALG_AES_IV_LEN 16
65 # define ALG_IV_LEN(len) (sizeof(struct af_alg_iv) + (len))
66 # define ALG_OP_TYPE     unsigned int
67 # define ALG_OP_LEN      (sizeof(ALG_OP_TYPE))
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 /* A version of 'struct timespec' with 32-bit time_t and nanoseconds.  */
128 struct __timespec32
129 {
130   __kernel_long_t tv_sec;
131   __kernel_long_t tv_nsec;
132 };
133 
134 static ossl_inline int io_getevents(aio_context_t ctx, long min, long max,
135                                struct io_event *events,
136                                struct timespec *timeout)
137 {
138 #if defined(__NR_io_pgetevents_time64)
139     /* Check if we are a 32-bit architecture with a 64-bit time_t */
140     if (sizeof(*timeout) != sizeof(struct __timespec32)) {
141         int ret = syscall(__NR_io_pgetevents_time64, ctx, min, max, events,
142                           timeout, NULL);
143         if (ret == 0 || errno != ENOSYS)
144             return ret;
145     }
146 #endif
147 
148 #if defined(__NR_io_getevents)
149     if (sizeof(*timeout) == sizeof(struct __timespec32))
150         /*
151          * time_t matches our architecture length, we can just use
152          * __NR_io_getevents
153          */
154         return syscall(__NR_io_getevents, ctx, min, max, events, timeout);
155     else {
156         /*
157          * We don't have __NR_io_pgetevents_time64, but we are using a
158          * 64-bit time_t on a 32-bit architecture. If we can fit the
159          * timeout value in a 32-bit time_t, then let's do that
160          * and then use the __NR_io_getevents syscall.
161          */
162         if (timeout && timeout->tv_sec == (long)timeout->tv_sec) {
163             struct __timespec32 ts32;
164 
165             ts32.tv_sec = (__kernel_long_t) timeout->tv_sec;
166             ts32.tv_nsec = (__kernel_long_t) timeout->tv_nsec;
167 
168             return syscall(__NR_io_getevents, ctx, min, max, events, ts32);
169         } else {
170             return syscall(__NR_io_getevents, ctx, min, max, events, NULL);
171         }
172     }
173 #endif
174 
175     errno = ENOSYS;
176     return -1;
177 }
178 
179 static void afalg_waitfd_cleanup(ASYNC_WAIT_CTX *ctx, const void *key,
180                                  OSSL_ASYNC_FD waitfd, void *custom)
181 {
182     close(waitfd);
183 }
184 
185 static int afalg_setup_async_event_notification(afalg_aio *aio)
186 {
187     ASYNC_JOB *job;
188     ASYNC_WAIT_CTX *waitctx;
189     void *custom = NULL;
190     int ret;
191 
192     if ((job = ASYNC_get_current_job()) != NULL) {
193         /* Async mode */
194         waitctx = ASYNC_get_wait_ctx(job);
195         if (waitctx == NULL) {
196             ALG_WARN("%s(%d): ASYNC_get_wait_ctx error", __FILE__, __LINE__);
197             return 0;
198         }
199         /* Get waitfd from ASYNC_WAIT_CTX if it is already set */
200         ret = ASYNC_WAIT_CTX_get_fd(waitctx, engine_afalg_id,
201                                     &aio->efd, &custom);
202         if (ret == 0) {
203             /*
204              * waitfd is not set in ASYNC_WAIT_CTX, create a new one
205              * and set it. efd will be signaled when AIO operation completes
206              */
207             aio->efd = eventfd(0);
208             if (aio->efd == -1) {
209                 ALG_PERR("%s(%d): Failed to get eventfd : ", __FILE__,
210                          __LINE__);
211                 AFALGerr(AFALG_F_AFALG_SETUP_ASYNC_EVENT_NOTIFICATION,
212                          AFALG_R_EVENTFD_FAILED);
213                 return 0;
214             }
215             ret = ASYNC_WAIT_CTX_set_wait_fd(waitctx, engine_afalg_id,
216                                              aio->efd, custom,
217                                              afalg_waitfd_cleanup);
218             if (ret == 0) {
219                 ALG_WARN("%s(%d): Failed to set wait fd", __FILE__, __LINE__);
220                 close(aio->efd);
221                 return 0;
222             }
223             /* make fd non-blocking in async mode */
224             if (fcntl(aio->efd, F_SETFL, O_NONBLOCK) != 0) {
225                 ALG_WARN("%s(%d): Failed to set event fd as NONBLOCKING",
226                          __FILE__, __LINE__);
227             }
228         }
229         aio->mode = MODE_ASYNC;
230     } else {
231         /* Sync mode */
232         aio->efd = eventfd(0);
233         if (aio->efd == -1) {
234             ALG_PERR("%s(%d): Failed to get eventfd : ", __FILE__, __LINE__);
235             AFALGerr(AFALG_F_AFALG_SETUP_ASYNC_EVENT_NOTIFICATION,
236                      AFALG_R_EVENTFD_FAILED);
237             return 0;
238         }
239         aio->mode = MODE_SYNC;
240     }
241     return 1;
242 }
243 
244 static int afalg_init_aio(afalg_aio *aio)
245 {
246     int r = -1;
247 
248     /* Initialise for AIO */
249     aio->aio_ctx = 0;
250     r = io_setup(MAX_INFLIGHTS, &aio->aio_ctx);
251     if (r < 0) {
252         ALG_PERR("%s(%d): io_setup error : ", __FILE__, __LINE__);
253         AFALGerr(AFALG_F_AFALG_INIT_AIO, AFALG_R_IO_SETUP_FAILED);
254         return 0;
255     }
256 
257     memset(aio->cbt, 0, sizeof(aio->cbt));
258     aio->efd = -1;
259     aio->mode = MODE_UNINIT;
260 
261     return 1;
262 }
263 
264 static int afalg_fin_cipher_aio(afalg_aio *aio, int sfd, unsigned char *buf,
265                                 size_t len)
266 {
267     int r;
268     int retry = 0;
269     unsigned int done = 0;
270     struct iocb *cb;
271     struct timespec timeout;
272     struct io_event events[MAX_INFLIGHTS];
273     u_int64_t eval = 0;
274 
275     timeout.tv_sec = 0;
276     timeout.tv_nsec = 0;
277 
278     /* if efd has not been initialised yet do it here */
279     if (aio->mode == MODE_UNINIT) {
280         r = afalg_setup_async_event_notification(aio);
281         if (r == 0)
282             return 0;
283     }
284 
285     cb = &(aio->cbt[0 % MAX_INFLIGHTS]);
286     memset(cb, '\0', sizeof(*cb));
287     cb->aio_fildes = sfd;
288     cb->aio_lio_opcode = IOCB_CMD_PREAD;
289     /*
290      * The pointer has to be converted to unsigned value first to avoid
291      * sign extension on cast to 64 bit value in 32-bit builds
292      */
293     cb->aio_buf = (size_t)buf;
294     cb->aio_offset = 0;
295     cb->aio_data = 0;
296     cb->aio_nbytes = len;
297     cb->aio_flags = IOCB_FLAG_RESFD;
298     cb->aio_resfd = aio->efd;
299 
300     /*
301      * Perform AIO read on AFALG socket, this in turn performs an async
302      * crypto operation in kernel space
303      */
304     r = io_read(aio->aio_ctx, 1, &cb);
305     if (r < 0) {
306         ALG_PWARN("%s(%d): io_read failed : ", __FILE__, __LINE__);
307         return 0;
308     }
309 
310     do {
311         /* While AIO read is being performed pause job */
312         ASYNC_pause_job();
313 
314         /* Check for completion of AIO read */
315         r = read(aio->efd, &eval, sizeof(eval));
316         if (r < 0) {
317             if (errno == EAGAIN || errno == EWOULDBLOCK)
318                 continue;
319             ALG_PERR("%s(%d): read failed for event fd : ", __FILE__, __LINE__);
320             return 0;
321         } else if (r == 0 || eval <= 0) {
322             ALG_WARN("%s(%d): eventfd read %d bytes, eval = %lu\n", __FILE__,
323                      __LINE__, r, eval);
324         }
325         if (eval > 0) {
326 
327 #ifdef OSSL_SANITIZE_MEMORY
328             /*
329              * In a memory sanitiser build, the changes to memory made by the
330              * system call aren't reliably detected.  By initialising the
331              * memory here, the sanitiser is told that they are okay.
332              */
333             memset(events, 0, sizeof(events));
334 #endif
335 
336             /* Get results of AIO read */
337             r = io_getevents(aio->aio_ctx, 1, MAX_INFLIGHTS,
338                              events, &timeout);
339             if (r > 0) {
340                 /*
341                  * events.res indicates the actual status of the operation.
342                  * Handle the error condition first.
343                  */
344                 if (events[0].res < 0) {
345                     /*
346                      * Underlying operation cannot be completed at the time
347                      * of previous submission. Resubmit for the operation.
348                      */
349                     if (events[0].res == -EBUSY && retry++ < 3) {
350                         r = io_read(aio->aio_ctx, 1, &cb);
351                         if (r < 0) {
352                             ALG_PERR("%s(%d): retry %d for io_read failed : ",
353                                      __FILE__, __LINE__, retry);
354                             return 0;
355                         }
356                         continue;
357                     } else {
358                         /*
359                          * Retries exceed for -EBUSY or unrecoverable error
360                          * condition for this instance of operation.
361                          */
362                         ALG_WARN
363                             ("%s(%d): Crypto Operation failed with code %lld\n",
364                              __FILE__, __LINE__, events[0].res);
365                         return 0;
366                     }
367                 }
368                 /* Operation successful. */
369                 done = 1;
370             } else if (r < 0) {
371                 ALG_PERR("%s(%d): io_getevents failed : ", __FILE__, __LINE__);
372                 return 0;
373             } else {
374                 ALG_WARN("%s(%d): io_geteventd read 0 bytes\n", __FILE__,
375                          __LINE__);
376             }
377         }
378     } while (!done);
379 
380     return 1;
381 }
382 
383 static ossl_inline void afalg_set_op_sk(struct cmsghdr *cmsg,
384                                    const ALG_OP_TYPE op)
385 {
386     cmsg->cmsg_level = SOL_ALG;
387     cmsg->cmsg_type = ALG_SET_OP;
388     cmsg->cmsg_len = CMSG_LEN(ALG_OP_LEN);
389     memcpy(CMSG_DATA(cmsg), &op, ALG_OP_LEN);
390 }
391 
392 static void afalg_set_iv_sk(struct cmsghdr *cmsg, const unsigned char *iv,
393                             const unsigned int len)
394 {
395     struct af_alg_iv *aiv;
396 
397     cmsg->cmsg_level = SOL_ALG;
398     cmsg->cmsg_type = ALG_SET_IV;
399     cmsg->cmsg_len = CMSG_LEN(ALG_IV_LEN(len));
400     aiv = (struct af_alg_iv *)CMSG_DATA(cmsg);
401     aiv->ivlen = len;
402     memcpy(aiv->iv, iv, len);
403 }
404 
405 static ossl_inline int afalg_set_key(afalg_ctx *actx, const unsigned char *key,
406                                 const int klen)
407 {
408     int ret;
409     ret = setsockopt(actx->bfd, SOL_ALG, ALG_SET_KEY, key, klen);
410     if (ret < 0) {
411         ALG_PERR("%s(%d): Failed to set socket option : ", __FILE__, __LINE__);
412         AFALGerr(AFALG_F_AFALG_SET_KEY, AFALG_R_SOCKET_SET_KEY_FAILED);
413         return 0;
414     }
415     return 1;
416 }
417 
418 static int afalg_create_sk(afalg_ctx *actx, const char *ciphertype,
419                                 const char *ciphername)
420 {
421     struct sockaddr_alg sa;
422     int r = -1;
423 
424     actx->bfd = actx->sfd = -1;
425 
426     memset(&sa, 0, sizeof(sa));
427     sa.salg_family = AF_ALG;
428     OPENSSL_strlcpy((char *) sa.salg_type, ciphertype, sizeof(sa.salg_type));
429     OPENSSL_strlcpy((char *) sa.salg_name, ciphername, sizeof(sa.salg_name));
430 
431     actx->bfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
432     if (actx->bfd == -1) {
433         ALG_PERR("%s(%d): Failed to open socket : ", __FILE__, __LINE__);
434         AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_CREATE_FAILED);
435         goto err;
436     }
437 
438     r = bind(actx->bfd, (struct sockaddr *)&sa, sizeof(sa));
439     if (r < 0) {
440         ALG_PERR("%s(%d): Failed to bind socket : ", __FILE__, __LINE__);
441         AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_BIND_FAILED);
442         goto err;
443     }
444 
445     actx->sfd = accept(actx->bfd, NULL, 0);
446     if (actx->sfd < 0) {
447         ALG_PERR("%s(%d): Socket Accept Failed : ", __FILE__, __LINE__);
448         AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_ACCEPT_FAILED);
449         goto err;
450     }
451 
452     return 1;
453 
454  err:
455     if (actx->bfd >= 0)
456         close(actx->bfd);
457     if (actx->sfd >= 0)
458         close(actx->sfd);
459     actx->bfd = actx->sfd = -1;
460     return 0;
461 }
462 
463 static int afalg_start_cipher_sk(afalg_ctx *actx, const unsigned char *in,
464                                  size_t inl, const unsigned char *iv,
465                                  unsigned int enc)
466 {
467     struct msghdr msg;
468     struct cmsghdr *cmsg;
469     struct iovec iov;
470     ssize_t sbytes;
471 # ifdef ALG_ZERO_COPY
472     int ret;
473 # endif
474     char cbuf[CMSG_SPACE(ALG_IV_LEN(ALG_AES_IV_LEN)) + CMSG_SPACE(ALG_OP_LEN)];
475 
476     memset(&msg, 0, sizeof(msg));
477     memset(cbuf, 0, sizeof(cbuf));
478     msg.msg_control = cbuf;
479     msg.msg_controllen = sizeof(cbuf);
480 
481     /*
482      * cipher direction (i.e. encrypt or decrypt) and iv are sent to the
483      * kernel as part of sendmsg()'s ancillary data
484      */
485     cmsg = CMSG_FIRSTHDR(&msg);
486     afalg_set_op_sk(cmsg, enc);
487     cmsg = CMSG_NXTHDR(&msg, cmsg);
488     afalg_set_iv_sk(cmsg, iv, ALG_AES_IV_LEN);
489 
490     /* iov that describes input data */
491     iov.iov_base = (unsigned char *)in;
492     iov.iov_len = inl;
493 
494     msg.msg_flags = MSG_MORE;
495 
496 # ifdef ALG_ZERO_COPY
497     /*
498      * ZERO_COPY mode
499      * Works best when buffer is 4k aligned
500      * OPENS: out of place processing (i.e. out != in)
501      */
502 
503     /* Input data is not sent as part of call to sendmsg() */
504     msg.msg_iovlen = 0;
505     msg.msg_iov = NULL;
506 
507     /* Sendmsg() sends iv and cipher direction to the kernel */
508     sbytes = sendmsg(actx->sfd, &msg, 0);
509     if (sbytes < 0) {
510         ALG_PERR("%s(%d): sendmsg failed for zero copy cipher operation : ",
511                  __FILE__, __LINE__);
512         return 0;
513     }
514 
515     /*
516      * vmsplice and splice are used to pin the user space input buffer for
517      * kernel space processing avoiding copies from user to kernel space
518      */
519     ret = vmsplice(actx->zc_pipe[1], &iov, 1, SPLICE_F_GIFT);
520     if (ret < 0) {
521         ALG_PERR("%s(%d): vmsplice failed : ", __FILE__, __LINE__);
522         return 0;
523     }
524 
525     ret = splice(actx->zc_pipe[0], NULL, actx->sfd, NULL, inl, 0);
526     if (ret < 0) {
527         ALG_PERR("%s(%d): splice failed : ", __FILE__, __LINE__);
528         return 0;
529     }
530 # else
531     msg.msg_iovlen = 1;
532     msg.msg_iov = &iov;
533 
534     /* Sendmsg() sends iv, cipher direction and input data to the kernel */
535     sbytes = sendmsg(actx->sfd, &msg, 0);
536     if (sbytes < 0) {
537         ALG_PERR("%s(%d): sendmsg failed for cipher operation : ", __FILE__,
538                  __LINE__);
539         return 0;
540     }
541 
542     if (sbytes != (ssize_t) inl) {
543         ALG_WARN("Cipher operation send bytes %zd != inlen %zd\n", sbytes,
544                 inl);
545         return 0;
546     }
547 # endif
548 
549     return 1;
550 }
551 
552 static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
553                              const unsigned char *iv, int enc)
554 {
555     int ciphertype;
556     int ret, len;
557     afalg_ctx *actx;
558     const char *ciphername;
559 
560     if (ctx == NULL || key == NULL) {
561         ALG_WARN("%s(%d): Null Parameter\n", __FILE__, __LINE__);
562         return 0;
563     }
564 
565     if (EVP_CIPHER_CTX_get0_cipher(ctx) == NULL) {
566         ALG_WARN("%s(%d): Cipher object NULL\n", __FILE__, __LINE__);
567         return 0;
568     }
569 
570     actx = EVP_CIPHER_CTX_get_cipher_data(ctx);
571     if (actx == NULL) {
572         ALG_WARN("%s(%d): Cipher data NULL\n", __FILE__, __LINE__);
573         return 0;
574     }
575 
576     ciphertype = EVP_CIPHER_CTX_get_nid(ctx);
577     switch (ciphertype) {
578     case NID_aes_128_cbc:
579     case NID_aes_192_cbc:
580     case NID_aes_256_cbc:
581         ciphername = "cbc(aes)";
582         break;
583     default:
584         ALG_WARN("%s(%d): Unsupported Cipher type %d\n", __FILE__, __LINE__,
585                  ciphertype);
586         return 0;
587     }
588 
589     if (ALG_AES_IV_LEN != EVP_CIPHER_CTX_get_iv_length(ctx)) {
590         ALG_WARN("%s(%d): Unsupported IV length :%d\n", __FILE__, __LINE__,
591                  EVP_CIPHER_CTX_get_iv_length(ctx));
592         return 0;
593     }
594 
595     /* Setup AFALG socket for crypto processing */
596     ret = afalg_create_sk(actx, "skcipher", ciphername);
597     if (ret < 1)
598         return 0;
599 
600     if ((len = EVP_CIPHER_CTX_get_key_length(ctx)) <= 0)
601         goto err;
602     ret = afalg_set_key(actx, key, len);
603     if (ret < 1)
604         goto err;
605 
606     /* Setup AIO ctx to allow async AFALG crypto processing */
607     if (afalg_init_aio(&actx->aio) == 0)
608         goto err;
609 
610 # ifdef ALG_ZERO_COPY
611     pipe(actx->zc_pipe);
612 # endif
613 
614     actx->init_done = MAGIC_INIT_NUM;
615 
616     return 1;
617 
618 err:
619     close(actx->sfd);
620     close(actx->bfd);
621     return 0;
622 }
623 
624 static int afalg_do_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
625                            const unsigned char *in, size_t inl)
626 {
627     afalg_ctx *actx;
628     int ret;
629     char nxtiv[ALG_AES_IV_LEN] = { 0 };
630 
631     if (ctx == NULL || out == NULL || in == NULL) {
632         ALG_WARN("NULL parameter passed to function %s(%d)\n", __FILE__,
633                  __LINE__);
634         return 0;
635     }
636 
637     actx = (afalg_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
638     if (actx == NULL || actx->init_done != MAGIC_INIT_NUM) {
639         ALG_WARN("%s afalg ctx passed\n",
640                  ctx == NULL ? "NULL" : "Uninitialised");
641         return 0;
642     }
643 
644     /*
645      * set iv now for decrypt operation as the input buffer can be
646      * overwritten for inplace operation where in = out.
647      */
648     if (EVP_CIPHER_CTX_is_encrypting(ctx) == 0) {
649         memcpy(nxtiv, in + (inl - ALG_AES_IV_LEN), ALG_AES_IV_LEN);
650     }
651 
652     /* Send input data to kernel space */
653     ret = afalg_start_cipher_sk(actx, (unsigned char *)in, inl,
654                                 EVP_CIPHER_CTX_iv(ctx),
655                                 EVP_CIPHER_CTX_is_encrypting(ctx));
656     if (ret < 1) {
657         return 0;
658     }
659 
660     /* Perform async crypto operation in kernel space */
661     ret = afalg_fin_cipher_aio(&actx->aio, actx->sfd, out, inl);
662     if (ret < 1)
663         return 0;
664 
665     if (EVP_CIPHER_CTX_is_encrypting(ctx)) {
666         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), out + (inl - ALG_AES_IV_LEN),
667                ALG_AES_IV_LEN);
668     } else {
669         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), nxtiv, ALG_AES_IV_LEN);
670     }
671 
672     return 1;
673 }
674 
675 static int afalg_cipher_cleanup(EVP_CIPHER_CTX *ctx)
676 {
677     afalg_ctx *actx;
678 
679     if (ctx == NULL) {
680         ALG_WARN("NULL parameter passed to function %s(%d)\n", __FILE__,
681                  __LINE__);
682         return 0;
683     }
684 
685     actx = (afalg_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
686     if (actx == NULL || actx->init_done != MAGIC_INIT_NUM)
687         return 1;
688 
689     close(actx->sfd);
690     close(actx->bfd);
691 # ifdef ALG_ZERO_COPY
692     close(actx->zc_pipe[0]);
693     close(actx->zc_pipe[1]);
694 # endif
695     /* close efd in sync mode, async mode is closed in afalg_waitfd_cleanup() */
696     if (actx->aio.mode == MODE_SYNC)
697         close(actx->aio.efd);
698     io_destroy(actx->aio.aio_ctx);
699 
700     return 1;
701 }
702 
703 static cbc_handles *get_cipher_handle(int nid)
704 {
705     switch (nid) {
706     case NID_aes_128_cbc:
707         return &cbc_handle[AES_CBC_128];
708     case NID_aes_192_cbc:
709         return &cbc_handle[AES_CBC_192];
710     case NID_aes_256_cbc:
711         return &cbc_handle[AES_CBC_256];
712     default:
713         return NULL;
714     }
715 }
716 
717 static const EVP_CIPHER *afalg_aes_cbc(int nid)
718 {
719     cbc_handles *cipher_handle = get_cipher_handle(nid);
720 
721     if (cipher_handle == NULL)
722             return NULL;
723     if (cipher_handle->_hidden == NULL
724         && ((cipher_handle->_hidden =
725          EVP_CIPHER_meth_new(nid,
726                              AES_BLOCK_SIZE,
727                              cipher_handle->key_size)) == NULL
728         || !EVP_CIPHER_meth_set_iv_length(cipher_handle->_hidden,
729                                           AES_IV_LEN)
730         || !EVP_CIPHER_meth_set_flags(cipher_handle->_hidden,
731                                       EVP_CIPH_CBC_MODE |
732                                       EVP_CIPH_FLAG_DEFAULT_ASN1)
733         || !EVP_CIPHER_meth_set_init(cipher_handle->_hidden,
734                                      afalg_cipher_init)
735         || !EVP_CIPHER_meth_set_do_cipher(cipher_handle->_hidden,
736                                           afalg_do_cipher)
737         || !EVP_CIPHER_meth_set_cleanup(cipher_handle->_hidden,
738                                         afalg_cipher_cleanup)
739         || !EVP_CIPHER_meth_set_impl_ctx_size(cipher_handle->_hidden,
740                                               sizeof(afalg_ctx)))) {
741         EVP_CIPHER_meth_free(cipher_handle->_hidden);
742         cipher_handle->_hidden= NULL;
743     }
744     return cipher_handle->_hidden;
745 }
746 
747 static int afalg_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
748                          const int **nids, int nid)
749 {
750     int r = 1;
751 
752     if (cipher == NULL) {
753         *nids = afalg_cipher_nids;
754         return (sizeof(afalg_cipher_nids) / sizeof(afalg_cipher_nids[0]));
755     }
756 
757     switch (nid) {
758     case NID_aes_128_cbc:
759     case NID_aes_192_cbc:
760     case NID_aes_256_cbc:
761         *cipher = afalg_aes_cbc(nid);
762         break;
763     default:
764         *cipher = NULL;
765         r = 0;
766     }
767     return r;
768 }
769 
770 static int bind_afalg(ENGINE *e)
771 {
772     /* Ensure the afalg error handling is set up */
773     unsigned short i;
774     ERR_load_AFALG_strings();
775 
776     if (!ENGINE_set_id(e, engine_afalg_id)
777         || !ENGINE_set_name(e, engine_afalg_name)
778         || !ENGINE_set_destroy_function(e, afalg_destroy)
779         || !ENGINE_set_init_function(e, afalg_init)
780         || !ENGINE_set_finish_function(e, afalg_finish)) {
781         AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
782         return 0;
783     }
784 
785     /*
786      * Create _hidden_aes_xxx_cbc by calling afalg_aes_xxx_cbc
787      * now, as bind_aflag can only be called by one thread at a
788      * time.
789      */
790     for(i = 0; i < OSSL_NELEM(afalg_cipher_nids); i++) {
791         if (afalg_aes_cbc(afalg_cipher_nids[i]) == NULL) {
792             AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
793             return 0;
794         }
795     }
796 
797     if (!ENGINE_set_ciphers(e, afalg_ciphers)) {
798         AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
799         return 0;
800     }
801 
802     return 1;
803 }
804 
805 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
806 static int bind_helper(ENGINE *e, const char *id)
807 {
808     if (id && (strcmp(id, engine_afalg_id) != 0))
809         return 0;
810 
811     if (!afalg_chk_platform())
812         return 0;
813 
814     if (!bind_afalg(e))
815         return 0;
816     return 1;
817 }
818 
819 IMPLEMENT_DYNAMIC_CHECK_FN()
820     IMPLEMENT_DYNAMIC_BIND_FN(bind_helper)
821 # endif
822 
823 static int afalg_chk_platform(void)
824 {
825     int ret;
826     int i;
827     int kver[3] = { -1, -1, -1 };
828     int sock;
829     char *str;
830     struct utsname ut;
831 
832     ret = uname(&ut);
833     if (ret != 0) {
834         AFALGerr(AFALG_F_AFALG_CHK_PLATFORM,
835                  AFALG_R_FAILED_TO_GET_PLATFORM_INFO);
836         return 0;
837     }
838 
839     str = strtok(ut.release, ".");
840     for (i = 0; i < 3 && str != NULL; i++) {
841         kver[i] = atoi(str);
842         str = strtok(NULL, ".");
843     }
844 
845     if (KERNEL_VERSION(kver[0], kver[1], kver[2])
846         < KERNEL_VERSION(K_MAJ, K_MIN1, K_MIN2)) {
847         ALG_ERR("ASYNC AFALG not supported this kernel(%d.%d.%d)\n",
848                  kver[0], kver[1], kver[2]);
849         ALG_ERR("ASYNC AFALG requires kernel version %d.%d.%d or later\n",
850                  K_MAJ, K_MIN1, K_MIN2);
851         AFALGerr(AFALG_F_AFALG_CHK_PLATFORM,
852                  AFALG_R_KERNEL_DOES_NOT_SUPPORT_ASYNC_AFALG);
853         return 0;
854     }
855 
856     /* Test if we can actually create an AF_ALG socket */
857     sock = socket(AF_ALG, SOCK_SEQPACKET, 0);
858     if (sock == -1) {
859         AFALGerr(AFALG_F_AFALG_CHK_PLATFORM, AFALG_R_SOCKET_CREATE_FAILED);
860         return 0;
861     }
862     close(sock);
863 
864     return 1;
865 }
866 
867 # ifdef OPENSSL_NO_DYNAMIC_ENGINE
868 static ENGINE *engine_afalg(void)
869 {
870     ENGINE *ret = ENGINE_new();
871     if (ret == NULL)
872         return NULL;
873     if (!bind_afalg(ret)) {
874         ENGINE_free(ret);
875         return NULL;
876     }
877     return ret;
878 }
879 
880 void engine_load_afalg_int(void)
881 {
882     ENGINE *toadd;
883 
884     if (!afalg_chk_platform())
885         return;
886 
887     toadd = engine_afalg();
888     if (toadd == NULL)
889         return;
890     ERR_set_mark();
891     ENGINE_add(toadd);
892     /*
893      * If the "add" worked, it gets a structural reference. So either way, we
894      * release our just-created reference.
895      */
896     ENGINE_free(toadd);
897     /*
898      * If the "add" didn't work, it was probably a conflict because it was
899      * already added (eg. someone calling ENGINE_load_blah then calling
900      * ENGINE_load_builtin_engines() perhaps).
901      */
902     ERR_pop_to_mark();
903 }
904 # endif
905 
906 static int afalg_init(ENGINE *e)
907 {
908     return 1;
909 }
910 
911 static int afalg_finish(ENGINE *e)
912 {
913     return 1;
914 }
915 
916 static int free_cbc(void)
917 {
918     short unsigned int i;
919     for(i = 0; i < OSSL_NELEM(afalg_cipher_nids); i++) {
920         EVP_CIPHER_meth_free(cbc_handle[i]._hidden);
921         cbc_handle[i]._hidden = NULL;
922     }
923     return 1;
924 }
925 
926 static int afalg_destroy(ENGINE *e)
927 {
928     ERR_unload_AFALG_strings();
929     free_cbc();
930     return 1;
931 }
932 
933 #endif                          /* KERNEL VERSION */
934