1/*
2 * Copyright 2016-2020 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
34void engine_load_afalg_int(void);
35void 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# ifdef OPENSSL_NO_DYNAMIC_ENGINE
67void engine_load_afalg_int(void);
68# endif
69
70/* Local Linkage Functions */
71static int afalg_init_aio(afalg_aio *aio);
72static int afalg_fin_cipher_aio(afalg_aio *ptr, int sfd,
73                                unsigned char *buf, size_t len);
74static int afalg_create_sk(afalg_ctx *actx, const char *ciphertype,
75                                const char *ciphername);
76static int afalg_destroy(ENGINE *e);
77static int afalg_init(ENGINE *e);
78static int afalg_finish(ENGINE *e);
79static const EVP_CIPHER *afalg_aes_cbc(int nid);
80static cbc_handles *get_cipher_handle(int nid);
81static int afalg_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
82                         const int **nids, int nid);
83static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
84                             const unsigned char *iv, int enc);
85static int afalg_do_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
86                           const unsigned char *in, size_t inl);
87static int afalg_cipher_cleanup(EVP_CIPHER_CTX *ctx);
88static int afalg_chk_platform(void);
89
90/* Engine Id and Name */
91static const char *engine_afalg_id = "afalg";
92static const char *engine_afalg_name = "AFALG engine support";
93
94static int afalg_cipher_nids[] = {
95    NID_aes_128_cbc,
96    NID_aes_192_cbc,
97    NID_aes_256_cbc,
98};
99
100static cbc_handles cbc_handle[] = {{AES_KEY_SIZE_128, NULL},
101                                    {AES_KEY_SIZE_192, NULL},
102                                    {AES_KEY_SIZE_256, NULL}};
103
104static ossl_inline int io_setup(unsigned n, aio_context_t *ctx)
105{
106    return syscall(__NR_io_setup, n, ctx);
107}
108
109static ossl_inline int eventfd(int n)
110{
111    return syscall(__NR_eventfd2, n, 0);
112}
113
114static ossl_inline int io_destroy(aio_context_t ctx)
115{
116    return syscall(__NR_io_destroy, ctx);
117}
118
119static ossl_inline int io_read(aio_context_t ctx, long n, struct iocb **iocb)
120{
121    return syscall(__NR_io_submit, ctx, n, iocb);
122}
123
124static ossl_inline int io_getevents(aio_context_t ctx, long min, long max,
125                               struct io_event *events,
126                               struct timespec *timeout)
127{
128    return syscall(__NR_io_getevents, ctx, min, max, events, timeout);
129}
130
131static void afalg_waitfd_cleanup(ASYNC_WAIT_CTX *ctx, const void *key,
132                                 OSSL_ASYNC_FD waitfd, void *custom)
133{
134    close(waitfd);
135}
136
137static int afalg_setup_async_event_notification(afalg_aio *aio)
138{
139    ASYNC_JOB *job;
140    ASYNC_WAIT_CTX *waitctx;
141    void *custom = NULL;
142    int ret;
143
144    if ((job = ASYNC_get_current_job()) != NULL) {
145        /* Async mode */
146        waitctx = ASYNC_get_wait_ctx(job);
147        if (waitctx == NULL) {
148            ALG_WARN("%s(%d): ASYNC_get_wait_ctx error", __FILE__, __LINE__);
149            return 0;
150        }
151        /* Get waitfd from ASYNC_WAIT_CTX if it is already set */
152        ret = ASYNC_WAIT_CTX_get_fd(waitctx, engine_afalg_id,
153                                    &aio->efd, &custom);
154        if (ret == 0) {
155            /*
156             * waitfd is not set in ASYNC_WAIT_CTX, create a new one
157             * and set it. efd will be signaled when AIO operation completes
158             */
159            aio->efd = eventfd(0);
160            if (aio->efd == -1) {
161                ALG_PERR("%s(%d): Failed to get eventfd : ", __FILE__,
162                         __LINE__);
163                AFALGerr(AFALG_F_AFALG_SETUP_ASYNC_EVENT_NOTIFICATION,
164                         AFALG_R_EVENTFD_FAILED);
165                return 0;
166            }
167            ret = ASYNC_WAIT_CTX_set_wait_fd(waitctx, engine_afalg_id,
168                                             aio->efd, custom,
169                                             afalg_waitfd_cleanup);
170            if (ret == 0) {
171                ALG_WARN("%s(%d): Failed to set wait fd", __FILE__, __LINE__);
172                close(aio->efd);
173                return 0;
174            }
175            /* make fd non-blocking in async mode */
176            if (fcntl(aio->efd, F_SETFL, O_NONBLOCK) != 0) {
177                ALG_WARN("%s(%d): Failed to set event fd as NONBLOCKING",
178                         __FILE__, __LINE__);
179            }
180        }
181        aio->mode = MODE_ASYNC;
182    } else {
183        /* Sync mode */
184        aio->efd = eventfd(0);
185        if (aio->efd == -1) {
186            ALG_PERR("%s(%d): Failed to get eventfd : ", __FILE__, __LINE__);
187            AFALGerr(AFALG_F_AFALG_SETUP_ASYNC_EVENT_NOTIFICATION,
188                     AFALG_R_EVENTFD_FAILED);
189            return 0;
190        }
191        aio->mode = MODE_SYNC;
192    }
193    return 1;
194}
195
196static int afalg_init_aio(afalg_aio *aio)
197{
198    int r = -1;
199
200    /* Initialise for AIO */
201    aio->aio_ctx = 0;
202    r = io_setup(MAX_INFLIGHTS, &aio->aio_ctx);
203    if (r < 0) {
204        ALG_PERR("%s(%d): io_setup error : ", __FILE__, __LINE__);
205        AFALGerr(AFALG_F_AFALG_INIT_AIO, AFALG_R_IO_SETUP_FAILED);
206        return 0;
207    }
208
209    memset(aio->cbt, 0, sizeof(aio->cbt));
210    aio->efd = -1;
211    aio->mode = MODE_UNINIT;
212
213    return 1;
214}
215
216static int afalg_fin_cipher_aio(afalg_aio *aio, int sfd, unsigned char *buf,
217                                size_t len)
218{
219    int r;
220    int retry = 0;
221    unsigned int done = 0;
222    struct iocb *cb;
223    struct timespec timeout;
224    struct io_event events[MAX_INFLIGHTS];
225    u_int64_t eval = 0;
226
227    timeout.tv_sec = 0;
228    timeout.tv_nsec = 0;
229
230    /* if efd has not been initialised yet do it here */
231    if (aio->mode == MODE_UNINIT) {
232        r = afalg_setup_async_event_notification(aio);
233        if (r == 0)
234            return 0;
235    }
236
237    cb = &(aio->cbt[0 % MAX_INFLIGHTS]);
238    memset(cb, '\0', sizeof(*cb));
239    cb->aio_fildes = sfd;
240    cb->aio_lio_opcode = IOCB_CMD_PREAD;
241    /*
242     * The pointer has to be converted to unsigned value first to avoid
243     * sign extension on cast to 64 bit value in 32-bit builds
244     */
245    cb->aio_buf = (size_t)buf;
246    cb->aio_offset = 0;
247    cb->aio_data = 0;
248    cb->aio_nbytes = len;
249    cb->aio_flags = IOCB_FLAG_RESFD;
250    cb->aio_resfd = aio->efd;
251
252    /*
253     * Perform AIO read on AFALG socket, this in turn performs an async
254     * crypto operation in kernel space
255     */
256    r = io_read(aio->aio_ctx, 1, &cb);
257    if (r < 0) {
258        ALG_PWARN("%s(%d): io_read failed : ", __FILE__, __LINE__);
259        return 0;
260    }
261
262    do {
263        /* While AIO read is being performed pause job */
264        ASYNC_pause_job();
265
266        /* Check for completion of AIO read */
267        r = read(aio->efd, &eval, sizeof(eval));
268        if (r < 0) {
269            if (errno == EAGAIN || errno == EWOULDBLOCK)
270                continue;
271            ALG_PERR("%s(%d): read failed for event fd : ", __FILE__, __LINE__);
272            return 0;
273        } else if (r == 0 || eval <= 0) {
274            ALG_WARN("%s(%d): eventfd read %d bytes, eval = %lu\n", __FILE__,
275                     __LINE__, r, eval);
276        }
277        if (eval > 0) {
278
279            /* Get results of AIO read */
280            r = io_getevents(aio->aio_ctx, 1, MAX_INFLIGHTS,
281                             events, &timeout);
282            if (r > 0) {
283                /*
284                 * events.res indicates the actual status of the operation.
285                 * Handle the error condition first.
286                 */
287                if (events[0].res < 0) {
288                    /*
289                     * Underlying operation cannot be completed at the time
290                     * of previous submission. Resubmit for the operation.
291                     */
292                    if (events[0].res == -EBUSY && retry++ < 3) {
293                        r = io_read(aio->aio_ctx, 1, &cb);
294                        if (r < 0) {
295                            ALG_PERR("%s(%d): retry %d for io_read failed : ",
296                                     __FILE__, __LINE__, retry);
297                            return 0;
298                        }
299                        continue;
300                    } else {
301                        /*
302                         * Retries exceed for -EBUSY or unrecoverable error
303                         * condition for this instance of operation.
304                         */
305                        ALG_WARN
306                            ("%s(%d): Crypto Operation failed with code %lld\n",
307                             __FILE__, __LINE__, events[0].res);
308                        return 0;
309                    }
310                }
311                /* Operation successful. */
312                done = 1;
313            } else if (r < 0) {
314                ALG_PERR("%s(%d): io_getevents failed : ", __FILE__, __LINE__);
315                return 0;
316            } else {
317                ALG_WARN("%s(%d): io_geteventd read 0 bytes\n", __FILE__,
318                         __LINE__);
319            }
320        }
321    } while (!done);
322
323    return 1;
324}
325
326static ossl_inline void afalg_set_op_sk(struct cmsghdr *cmsg,
327                                   const ALG_OP_TYPE op)
328{
329    cmsg->cmsg_level = SOL_ALG;
330    cmsg->cmsg_type = ALG_SET_OP;
331    cmsg->cmsg_len = CMSG_LEN(ALG_OP_LEN);
332    memcpy(CMSG_DATA(cmsg), &op, ALG_OP_LEN);
333}
334
335static void afalg_set_iv_sk(struct cmsghdr *cmsg, const unsigned char *iv,
336                            const unsigned int len)
337{
338    struct af_alg_iv *aiv;
339
340    cmsg->cmsg_level = SOL_ALG;
341    cmsg->cmsg_type = ALG_SET_IV;
342    cmsg->cmsg_len = CMSG_LEN(ALG_IV_LEN(len));
343    aiv = (struct af_alg_iv *)CMSG_DATA(cmsg);
344    aiv->ivlen = len;
345    memcpy(aiv->iv, iv, len);
346}
347
348static ossl_inline int afalg_set_key(afalg_ctx *actx, const unsigned char *key,
349                                const int klen)
350{
351    int ret;
352    ret = setsockopt(actx->bfd, SOL_ALG, ALG_SET_KEY, key, klen);
353    if (ret < 0) {
354        ALG_PERR("%s(%d): Failed to set socket option : ", __FILE__, __LINE__);
355        AFALGerr(AFALG_F_AFALG_SET_KEY, AFALG_R_SOCKET_SET_KEY_FAILED);
356        return 0;
357    }
358    return 1;
359}
360
361static int afalg_create_sk(afalg_ctx *actx, const char *ciphertype,
362                                const char *ciphername)
363{
364    struct sockaddr_alg sa;
365    int r = -1;
366
367    actx->bfd = actx->sfd = -1;
368
369    memset(&sa, 0, sizeof(sa));
370    sa.salg_family = AF_ALG;
371    OPENSSL_strlcpy((char *) sa.salg_type, ciphertype, sizeof(sa.salg_type));
372    OPENSSL_strlcpy((char *) sa.salg_name, ciphername, sizeof(sa.salg_name));
373
374    actx->bfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
375    if (actx->bfd == -1) {
376        ALG_PERR("%s(%d): Failed to open socket : ", __FILE__, __LINE__);
377        AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_CREATE_FAILED);
378        goto err;
379    }
380
381    r = bind(actx->bfd, (struct sockaddr *)&sa, sizeof(sa));
382    if (r < 0) {
383        ALG_PERR("%s(%d): Failed to bind socket : ", __FILE__, __LINE__);
384        AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_BIND_FAILED);
385        goto err;
386    }
387
388    actx->sfd = accept(actx->bfd, NULL, 0);
389    if (actx->sfd < 0) {
390        ALG_PERR("%s(%d): Socket Accept Failed : ", __FILE__, __LINE__);
391        AFALGerr(AFALG_F_AFALG_CREATE_SK, AFALG_R_SOCKET_ACCEPT_FAILED);
392        goto err;
393    }
394
395    return 1;
396
397 err:
398    if (actx->bfd >= 0)
399        close(actx->bfd);
400    if (actx->sfd >= 0)
401        close(actx->sfd);
402    actx->bfd = actx->sfd = -1;
403    return 0;
404}
405
406static int afalg_start_cipher_sk(afalg_ctx *actx, const unsigned char *in,
407                                 size_t inl, const unsigned char *iv,
408                                 unsigned int enc)
409{
410    struct msghdr msg = { 0 };
411    struct cmsghdr *cmsg;
412    struct iovec iov;
413    ssize_t sbytes;
414# ifdef ALG_ZERO_COPY
415    int ret;
416# endif
417    char cbuf[CMSG_SPACE(ALG_IV_LEN(ALG_AES_IV_LEN)) + CMSG_SPACE(ALG_OP_LEN)];
418
419    memset(cbuf, 0, sizeof(cbuf));
420    msg.msg_control = cbuf;
421    msg.msg_controllen = sizeof(cbuf);
422
423    /*
424     * cipher direction (i.e. encrypt or decrypt) and iv are sent to the
425     * kernel as part of sendmsg()'s ancillary data
426     */
427    cmsg = CMSG_FIRSTHDR(&msg);
428    afalg_set_op_sk(cmsg, enc);
429    cmsg = CMSG_NXTHDR(&msg, cmsg);
430    afalg_set_iv_sk(cmsg, iv, ALG_AES_IV_LEN);
431
432    /* iov that describes input data */
433    iov.iov_base = (unsigned char *)in;
434    iov.iov_len = inl;
435
436    msg.msg_flags = MSG_MORE;
437
438# ifdef ALG_ZERO_COPY
439    /*
440     * ZERO_COPY mode
441     * Works best when buffer is 4k aligned
442     * OPENS: out of place processing (i.e. out != in)
443     */
444
445    /* Input data is not sent as part of call to sendmsg() */
446    msg.msg_iovlen = 0;
447    msg.msg_iov = NULL;
448
449    /* Sendmsg() sends iv and cipher direction to the kernel */
450    sbytes = sendmsg(actx->sfd, &msg, 0);
451    if (sbytes < 0) {
452        ALG_PERR("%s(%d): sendmsg failed for zero copy cipher operation : ",
453                 __FILE__, __LINE__);
454        return 0;
455    }
456
457    /*
458     * vmsplice and splice are used to pin the user space input buffer for
459     * kernel space processing avoiding copies from user to kernel space
460     */
461    ret = vmsplice(actx->zc_pipe[1], &iov, 1, SPLICE_F_GIFT);
462    if (ret < 0) {
463        ALG_PERR("%s(%d): vmsplice failed : ", __FILE__, __LINE__);
464        return 0;
465    }
466
467    ret = splice(actx->zc_pipe[0], NULL, actx->sfd, NULL, inl, 0);
468    if (ret < 0) {
469        ALG_PERR("%s(%d): splice failed : ", __FILE__, __LINE__);
470        return 0;
471    }
472# else
473    msg.msg_iovlen = 1;
474    msg.msg_iov = &iov;
475
476    /* Sendmsg() sends iv, cipher direction and input data to the kernel */
477    sbytes = sendmsg(actx->sfd, &msg, 0);
478    if (sbytes < 0) {
479        ALG_PERR("%s(%d): sendmsg failed for cipher operation : ", __FILE__,
480                 __LINE__);
481        return 0;
482    }
483
484    if (sbytes != (ssize_t) inl) {
485        ALG_WARN("Cipher operation send bytes %zd != inlen %zd\n", sbytes,
486                inl);
487        return 0;
488    }
489# endif
490
491    return 1;
492}
493
494static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
495                             const unsigned char *iv, int enc)
496{
497    int ciphertype;
498    int ret;
499    afalg_ctx *actx;
500    const char *ciphername;
501
502    if (ctx == NULL || key == NULL) {
503        ALG_WARN("%s(%d): Null Parameter\n", __FILE__, __LINE__);
504        return 0;
505    }
506
507    if (EVP_CIPHER_CTX_cipher(ctx) == NULL) {
508        ALG_WARN("%s(%d): Cipher object NULL\n", __FILE__, __LINE__);
509        return 0;
510    }
511
512    actx = EVP_CIPHER_CTX_get_cipher_data(ctx);
513    if (actx == NULL) {
514        ALG_WARN("%s(%d): Cipher data NULL\n", __FILE__, __LINE__);
515        return 0;
516    }
517
518    ciphertype = EVP_CIPHER_CTX_nid(ctx);
519    switch (ciphertype) {
520    case NID_aes_128_cbc:
521    case NID_aes_192_cbc:
522    case NID_aes_256_cbc:
523        ciphername = "cbc(aes)";
524        break;
525    default:
526        ALG_WARN("%s(%d): Unsupported Cipher type %d\n", __FILE__, __LINE__,
527                 ciphertype);
528        return 0;
529    }
530
531    if (ALG_AES_IV_LEN != EVP_CIPHER_CTX_iv_length(ctx)) {
532        ALG_WARN("%s(%d): Unsupported IV length :%d\n", __FILE__, __LINE__,
533                 EVP_CIPHER_CTX_iv_length(ctx));
534        return 0;
535    }
536
537    /* Setup AFALG socket for crypto processing */
538    ret = afalg_create_sk(actx, "skcipher", ciphername);
539    if (ret < 1)
540        return 0;
541
542
543    ret = afalg_set_key(actx, key, EVP_CIPHER_CTX_key_length(ctx));
544    if (ret < 1)
545        goto err;
546
547    /* Setup AIO ctx to allow async AFALG crypto processing */
548    if (afalg_init_aio(&actx->aio) == 0)
549        goto err;
550
551# ifdef ALG_ZERO_COPY
552    pipe(actx->zc_pipe);
553# endif
554
555    actx->init_done = MAGIC_INIT_NUM;
556
557    return 1;
558
559err:
560    close(actx->sfd);
561    close(actx->bfd);
562    return 0;
563}
564
565static int afalg_do_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
566                           const unsigned char *in, size_t inl)
567{
568    afalg_ctx *actx;
569    int ret;
570    char nxtiv[ALG_AES_IV_LEN] = { 0 };
571
572    if (ctx == NULL || out == NULL || in == NULL) {
573        ALG_WARN("NULL parameter passed to function %s(%d)\n", __FILE__,
574                 __LINE__);
575        return 0;
576    }
577
578    actx = (afalg_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
579    if (actx == NULL || actx->init_done != MAGIC_INIT_NUM) {
580        ALG_WARN("%s afalg ctx passed\n",
581                 ctx == NULL ? "NULL" : "Uninitialised");
582        return 0;
583    }
584
585    /*
586     * set iv now for decrypt operation as the input buffer can be
587     * overwritten for inplace operation where in = out.
588     */
589    if (EVP_CIPHER_CTX_encrypting(ctx) == 0) {
590        memcpy(nxtiv, in + (inl - ALG_AES_IV_LEN), ALG_AES_IV_LEN);
591    }
592
593    /* Send input data to kernel space */
594    ret = afalg_start_cipher_sk(actx, (unsigned char *)in, inl,
595                                EVP_CIPHER_CTX_iv(ctx),
596                                EVP_CIPHER_CTX_encrypting(ctx));
597    if (ret < 1) {
598        return 0;
599    }
600
601    /* Perform async crypto operation in kernel space */
602    ret = afalg_fin_cipher_aio(&actx->aio, actx->sfd, out, inl);
603    if (ret < 1)
604        return 0;
605
606    if (EVP_CIPHER_CTX_encrypting(ctx)) {
607        memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), out + (inl - ALG_AES_IV_LEN),
608               ALG_AES_IV_LEN);
609    } else {
610        memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), nxtiv, ALG_AES_IV_LEN);
611    }
612
613    return 1;
614}
615
616static int afalg_cipher_cleanup(EVP_CIPHER_CTX *ctx)
617{
618    afalg_ctx *actx;
619
620    if (ctx == NULL) {
621        ALG_WARN("NULL parameter passed to function %s(%d)\n", __FILE__,
622                 __LINE__);
623        return 0;
624    }
625
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");
630        return 0;
631    }
632
633    close(actx->sfd);
634    close(actx->bfd);
635# ifdef ALG_ZERO_COPY
636    close(actx->zc_pipe[0]);
637    close(actx->zc_pipe[1]);
638# endif
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);
643
644    return 1;
645}
646
647static cbc_handles *get_cipher_handle(int nid)
648{
649    switch (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];
656    default:
657        return NULL;
658    }
659}
660
661static const EVP_CIPHER *afalg_aes_cbc(int nid)
662{
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,
667                             AES_BLOCK_SIZE,
668                             cipher_handle->key_size)) == NULL
669        || !EVP_CIPHER_meth_set_iv_length(cipher_handle->_hidden,
670                                          AES_IV_LEN)
671        || !EVP_CIPHER_meth_set_flags(cipher_handle->_hidden,
672                                      EVP_CIPH_CBC_MODE |
673                                      EVP_CIPH_FLAG_DEFAULT_ASN1)
674        || !EVP_CIPHER_meth_set_init(cipher_handle->_hidden,
675                                     afalg_cipher_init)
676        || !EVP_CIPHER_meth_set_do_cipher(cipher_handle->_hidden,
677                                          afalg_do_cipher)
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;
684    }
685    return cipher_handle->_hidden;
686}
687
688static int afalg_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
689                         const int **nids, int nid)
690{
691    int r = 1;
692
693    if (cipher == NULL) {
694        *nids = afalg_cipher_nids;
695        return (sizeof(afalg_cipher_nids) / sizeof(afalg_cipher_nids[0]));
696    }
697
698    switch (nid) {
699    case NID_aes_128_cbc:
700    case NID_aes_192_cbc:
701    case NID_aes_256_cbc:
702        *cipher = afalg_aes_cbc(nid);
703        break;
704    default:
705        *cipher = NULL;
706        r = 0;
707    }
708    return r;
709}
710
711static int bind_afalg(ENGINE *e)
712{
713    /* Ensure the afalg error handling is set up */
714    unsigned short i;
715    ERR_load_AFALG_strings();
716
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);
723        return 0;
724    }
725
726    /*
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
729     * time.
730     */
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);
734            return 0;
735        }
736    }
737
738    if (!ENGINE_set_ciphers(e, afalg_ciphers)) {
739        AFALGerr(AFALG_F_BIND_AFALG, AFALG_R_INIT_FAILED);
740        return 0;
741    }
742
743    return 1;
744}
745
746# ifndef OPENSSL_NO_DYNAMIC_ENGINE
747static int bind_helper(ENGINE *e, const char *id)
748{
749    if (id && (strcmp(id, engine_afalg_id) != 0))
750        return 0;
751
752    if (!afalg_chk_platform())
753        return 0;
754
755    if (!bind_afalg(e))
756        return 0;
757    return 1;
758}
759
760IMPLEMENT_DYNAMIC_CHECK_FN()
761    IMPLEMENT_DYNAMIC_BIND_FN(bind_helper)
762# endif
763
764static int afalg_chk_platform(void)
765{
766    int ret;
767    int i;
768    int kver[3] = { -1, -1, -1 };
769    int sock;
770    char *str;
771    struct utsname ut;
772
773    ret = uname(&ut);
774    if (ret != 0) {
775        AFALGerr(AFALG_F_AFALG_CHK_PLATFORM,
776                 AFALG_R_FAILED_TO_GET_PLATFORM_INFO);
777        return 0;
778    }
779
780    str = strtok(ut.release, ".");
781    for (i = 0; i < 3 && str != NULL; i++) {
782        kver[i] = atoi(str);
783        str = strtok(NULL, ".");
784    }
785
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);
794        return 0;
795    }
796
797    /* Test if we can actually create an AF_ALG socket */
798    sock = socket(AF_ALG, SOCK_SEQPACKET, 0);
799    if (sock == -1) {
800        AFALGerr(AFALG_F_AFALG_CHK_PLATFORM, AFALG_R_SOCKET_CREATE_FAILED);
801        return 0;
802    }
803    close(sock);
804
805    return 1;
806}
807
808# ifdef OPENSSL_NO_DYNAMIC_ENGINE
809static ENGINE *engine_afalg(void)
810{
811    ENGINE *ret = ENGINE_new();
812    if (ret == NULL)
813        return NULL;
814    if (!bind_afalg(ret)) {
815        ENGINE_free(ret);
816        return NULL;
817    }
818    return ret;
819}
820
821void engine_load_afalg_int(void)
822{
823    ENGINE *toadd;
824
825    if (!afalg_chk_platform())
826        return;
827
828    toadd = engine_afalg();
829    if (toadd == NULL)
830        return;
831    ENGINE_add(toadd);
832    ENGINE_free(toadd);
833    ERR_clear_error();
834}
835# endif
836
837static int afalg_init(ENGINE *e)
838{
839    return 1;
840}
841
842static int afalg_finish(ENGINE *e)
843{
844    return 1;
845}
846
847static int free_cbc(void)
848{
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;
853    }
854    return 1;
855}
856
857static int afalg_destroy(ENGINE *e)
858{
859    ERR_unload_AFALG_strings();
860    free_cbc();
861    return 1;
862}
863
864#endif                          /* KERNEL VERSION */
865