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[dragonfly.git] / crypto / openssl / crypto / evp / e_aes_cbc_hmac_sha1.c
1 /* ====================================================================
2  * Copyright (c) 2011-2013 The OpenSSL Project.  All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in
13  *    the documentation and/or other materials provided with the
14  *    distribution.
15  *
16  * 3. All advertising materials mentioning features or use of this
17  *    software must display the following acknowledgment:
18  *    "This product includes software developed by the OpenSSL Project
19  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
20  *
21  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
22  *    endorse or promote products derived from this software without
23  *    prior written permission. For written permission, please contact
24  *    licensing@OpenSSL.org.
25  *
26  * 5. Products derived from this software may not be called "OpenSSL"
27  *    nor may "OpenSSL" appear in their names without prior written
28  *    permission of the OpenSSL Project.
29  *
30  * 6. Redistributions of any form whatsoever must retain the following
31  *    acknowledgment:
32  *    "This product includes software developed by the OpenSSL Project
33  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
34  *
35  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
36  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
37  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
38  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
39  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
41  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
42  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
44  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
45  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
46  * OF THE POSSIBILITY OF SUCH DAMAGE.
47  * ====================================================================
48  */
49
50 #include <openssl/opensslconf.h>
51
52 #include <stdio.h>
53 #include <string.h>
54
55 #if !defined(OPENSSL_NO_AES) && !defined(OPENSSL_NO_SHA1)
56
57 #include <openssl/evp.h>
58 #include <openssl/objects.h>
59 #include <openssl/aes.h>
60 #include <openssl/sha.h>
61 #include "evp_locl.h"
62
63 #ifndef EVP_CIPH_FLAG_AEAD_CIPHER
64 #define EVP_CIPH_FLAG_AEAD_CIPHER       0x200000
65 #define EVP_CTRL_AEAD_TLS1_AAD          0x16
66 #define EVP_CTRL_AEAD_SET_MAC_KEY       0x17
67 #endif
68
69 #if !defined(EVP_CIPH_FLAG_DEFAULT_ASN1)
70 #define EVP_CIPH_FLAG_DEFAULT_ASN1 0
71 #endif
72
73 #define TLS1_1_VERSION 0x0302
74
75 typedef struct
76     {
77     AES_KEY             ks;
78     SHA_CTX             head,tail,md;
79     size_t              payload_length; /* AAD length in decrypt case */
80     union {
81         unsigned int    tls_ver;
82         unsigned char   tls_aad[16];    /* 13 used */
83     } aux;
84     } EVP_AES_HMAC_SHA1;
85
86 #define NO_PAYLOAD_LENGTH       ((size_t)-1)
87
88 #if     defined(AES_ASM) &&     ( \
89         defined(__x86_64)       || defined(__x86_64__)  || \
90         defined(_M_AMD64)       || defined(_M_X64)      || \
91         defined(__INTEL__)      )
92
93 #if defined(__GNUC__) && __GNUC__>=2 && !defined(PEDANTIC)
94 # define BSWAP(x) ({ unsigned int r=(x); asm ("bswapl %0":"=r"(r):"0"(r)); r; })
95 #endif
96
97 extern unsigned int OPENSSL_ia32cap_P[2];
98 #define AESNI_CAPABLE   (1<<(57-32))
99
100 int aesni_set_encrypt_key(const unsigned char *userKey, int bits,
101                               AES_KEY *key);
102 int aesni_set_decrypt_key(const unsigned char *userKey, int bits,
103                               AES_KEY *key);
104
105 void aesni_cbc_encrypt(const unsigned char *in,
106                            unsigned char *out,
107                            size_t length,
108                            const AES_KEY *key,
109                            unsigned char *ivec, int enc);
110
111 void aesni_cbc_sha1_enc (const void *inp, void *out, size_t blocks,
112                 const AES_KEY *key, unsigned char iv[16],
113                 SHA_CTX *ctx,const void *in0);
114
115 #define data(ctx) ((EVP_AES_HMAC_SHA1 *)(ctx)->cipher_data)
116
117 static int aesni_cbc_hmac_sha1_init_key(EVP_CIPHER_CTX *ctx,
118                         const unsigned char *inkey,
119                         const unsigned char *iv, int enc)
120         {
121         EVP_AES_HMAC_SHA1 *key = data(ctx);
122         int ret;
123
124         if (enc)
125                 ret=aesni_set_encrypt_key(inkey,ctx->key_len*8,&key->ks);
126         else
127                 ret=aesni_set_decrypt_key(inkey,ctx->key_len*8,&key->ks);
128
129         SHA1_Init(&key->head);  /* handy when benchmarking */
130         key->tail = key->head;
131         key->md   = key->head;
132
133         key->payload_length = NO_PAYLOAD_LENGTH;
134
135         return ret<0?0:1;
136         }
137
138 #define STITCHED_CALL
139
140 #if !defined(STITCHED_CALL)
141 #define aes_off 0
142 #endif
143
144 void sha1_block_data_order (void *c,const void *p,size_t len);
145
146 static void sha1_update(SHA_CTX *c,const void *data,size_t len)
147 {       const unsigned char *ptr = data;
148         size_t res;
149
150         if ((res = c->num)) {
151                 res = SHA_CBLOCK-res;
152                 if (len<res) res=len;
153                 SHA1_Update (c,ptr,res);
154                 ptr += res;
155                 len -= res;
156         }
157
158         res = len % SHA_CBLOCK;
159         len -= res;
160
161         if (len) {
162                 sha1_block_data_order(c,ptr,len/SHA_CBLOCK);
163
164                 ptr += len;
165                 c->Nh += len>>29;
166                 c->Nl += len<<=3;
167                 if (c->Nl<(unsigned int)len) c->Nh++;
168         }
169
170         if (res)
171                 SHA1_Update(c,ptr,res);
172 }
173
174 #ifdef SHA1_Update
175 #undef SHA1_Update
176 #endif
177 #define SHA1_Update sha1_update
178
179 static int aesni_cbc_hmac_sha1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
180                       const unsigned char *in, size_t len)
181         {
182         EVP_AES_HMAC_SHA1 *key = data(ctx);
183         unsigned int l;
184         size_t  plen = key->payload_length,
185                 iv = 0,         /* explicit IV in TLS 1.1 and later */
186                 sha_off = 0;
187 #if defined(STITCHED_CALL)
188         size_t  aes_off = 0,
189                 blocks;
190
191         sha_off = SHA_CBLOCK-key->md.num;
192 #endif
193
194         key->payload_length = NO_PAYLOAD_LENGTH;
195
196         if (len%AES_BLOCK_SIZE) return 0;
197
198         if (ctx->encrypt) {
199                 if (plen==NO_PAYLOAD_LENGTH)
200                         plen = len;
201                 else if (len!=((plen+SHA_DIGEST_LENGTH+AES_BLOCK_SIZE)&-AES_BLOCK_SIZE))
202                         return 0;
203                 else if (key->aux.tls_ver >= TLS1_1_VERSION)
204                         iv = AES_BLOCK_SIZE;
205
206 #if defined(STITCHED_CALL)
207                 if (plen>(sha_off+iv) && (blocks=(plen-(sha_off+iv))/SHA_CBLOCK)) {
208                         SHA1_Update(&key->md,in+iv,sha_off);
209
210                         aesni_cbc_sha1_enc(in,out,blocks,&key->ks,
211                                 ctx->iv,&key->md,in+iv+sha_off);
212                         blocks *= SHA_CBLOCK;
213                         aes_off += blocks;
214                         sha_off += blocks;
215                         key->md.Nh += blocks>>29;
216                         key->md.Nl += blocks<<=3;
217                         if (key->md.Nl<(unsigned int)blocks) key->md.Nh++;
218                 } else {
219                         sha_off = 0;
220                 }
221 #endif
222                 sha_off += iv;
223                 SHA1_Update(&key->md,in+sha_off,plen-sha_off);
224
225                 if (plen!=len)  {       /* "TLS" mode of operation */
226                         if (in!=out)
227                                 memcpy(out+aes_off,in+aes_off,plen-aes_off);
228
229                         /* calculate HMAC and append it to payload */
230                         SHA1_Final(out+plen,&key->md);
231                         key->md = key->tail;
232                         SHA1_Update(&key->md,out+plen,SHA_DIGEST_LENGTH);
233                         SHA1_Final(out+plen,&key->md);
234
235                         /* pad the payload|hmac */
236                         plen += SHA_DIGEST_LENGTH;
237                         for (l=len-plen-1;plen<len;plen++) out[plen]=l;
238                         /* encrypt HMAC|padding at once */
239                         aesni_cbc_encrypt(out+aes_off,out+aes_off,len-aes_off,
240                                         &key->ks,ctx->iv,1);
241                 } else {
242                         aesni_cbc_encrypt(in+aes_off,out+aes_off,len-aes_off,
243                                         &key->ks,ctx->iv,1);
244                 }
245         } else {
246                 union { unsigned int  u[SHA_DIGEST_LENGTH/sizeof(unsigned int)];
247                         unsigned char c[SHA_DIGEST_LENGTH]; } mac;
248
249                 /* decrypt HMAC|padding at once */
250                 aesni_cbc_encrypt(in,out,len,
251                                 &key->ks,ctx->iv,0);
252
253                 if (plen) {     /* "TLS" mode of operation */
254                         size_t inp_len, mask, j, i;
255                         unsigned int res, maxpad, pad, bitlen;
256                         int ret = 1;
257                         union { unsigned int  u[SHA_LBLOCK];
258                                 unsigned char c[SHA_CBLOCK]; }
259                                 *data = (void *)key->md.data;
260
261                         if ((key->aux.tls_aad[plen-4]<<8|key->aux.tls_aad[plen-3])
262                             >= TLS1_1_VERSION)
263                                 iv = AES_BLOCK_SIZE;
264
265                         if (len<(iv+SHA_DIGEST_LENGTH+1))
266                                 return 0;
267
268                         /* omit explicit iv */
269                         out += iv;
270                         len -= iv;
271
272                         /* figure out payload length */
273                         pad = out[len-1];
274                         maxpad = len-(SHA_DIGEST_LENGTH+1);
275                         maxpad |= (255-maxpad)>>(sizeof(maxpad)*8-8);
276                         maxpad &= 255;
277
278                         inp_len = len - (SHA_DIGEST_LENGTH+pad+1);
279                         mask = (0-((inp_len-len)>>(sizeof(inp_len)*8-1)));
280                         inp_len &= mask;
281                         ret &= (int)mask;
282
283                         key->aux.tls_aad[plen-2] = inp_len>>8;
284                         key->aux.tls_aad[plen-1] = inp_len;
285
286                         /* calculate HMAC */
287                         key->md = key->head;
288                         SHA1_Update(&key->md,key->aux.tls_aad,plen);
289
290 #if 1
291                         len -= SHA_DIGEST_LENGTH;               /* amend mac */
292                         if (len>=(256+SHA_CBLOCK)) {
293                                 j = (len-(256+SHA_CBLOCK))&(0-SHA_CBLOCK);
294                                 j += SHA_CBLOCK-key->md.num;
295                                 SHA1_Update(&key->md,out,j);
296                                 out += j;
297                                 len -= j;
298                                 inp_len -= j;
299                         }
300
301                         /* but pretend as if we hashed padded payload */
302                         bitlen = key->md.Nl+(inp_len<<3);       /* at most 18 bits */
303                         mac.c[0] = 0;
304                         mac.c[1] = (unsigned char)(bitlen>>16);
305                         mac.c[2] = (unsigned char)(bitlen>>8);
306                         mac.c[3] = (unsigned char)bitlen;
307                         bitlen = mac.u[0];
308
309                         mac.u[0]=0;
310                         mac.u[1]=0;
311                         mac.u[2]=0;
312                         mac.u[3]=0;
313                         mac.u[4]=0;
314
315                         for (res=key->md.num, j=0;j<len;j++) {
316                                 size_t c = out[j];
317                                 mask = (j-inp_len)>>(sizeof(j)*8-8);
318                                 c &= mask;
319                                 c |= 0x80&~mask&~((inp_len-j)>>(sizeof(j)*8-8));
320                                 data->c[res++]=(unsigned char)c;
321
322                                 if (res!=SHA_CBLOCK) continue;
323
324                                 mask = 0-((inp_len+8-j)>>(sizeof(j)*8-1));
325                                 data->u[SHA_LBLOCK-1] |= bitlen&mask;
326                                 sha1_block_data_order(&key->md,data,1);
327                                 mask &= 0-((j-inp_len-73)>>(sizeof(j)*8-1));
328                                 mac.u[0] |= key->md.h0 & mask;
329                                 mac.u[1] |= key->md.h1 & mask;
330                                 mac.u[2] |= key->md.h2 & mask;
331                                 mac.u[3] |= key->md.h3 & mask;
332                                 mac.u[4] |= key->md.h4 & mask;
333                                 res=0;
334                         }
335
336                         for(i=res;i<SHA_CBLOCK;i++,j++) data->c[i]=0;
337
338                         if (res>SHA_CBLOCK-8) {
339                                 mask = 0-((inp_len+8-j)>>(sizeof(j)*8-1));
340                                 data->u[SHA_LBLOCK-1] |= bitlen&mask;
341                                 sha1_block_data_order(&key->md,data,1);
342                                 mask &= 0-((j-inp_len-73)>>(sizeof(j)*8-1));
343                                 mac.u[0] |= key->md.h0 & mask;
344                                 mac.u[1] |= key->md.h1 & mask;
345                                 mac.u[2] |= key->md.h2 & mask;
346                                 mac.u[3] |= key->md.h3 & mask;
347                                 mac.u[4] |= key->md.h4 & mask;
348
349                                 memset(data,0,SHA_CBLOCK);
350                                 j+=64;
351                         }
352                         data->u[SHA_LBLOCK-1] = bitlen;
353                         sha1_block_data_order(&key->md,data,1);
354                         mask = 0-((j-inp_len-73)>>(sizeof(j)*8-1));
355                         mac.u[0] |= key->md.h0 & mask;
356                         mac.u[1] |= key->md.h1 & mask;
357                         mac.u[2] |= key->md.h2 & mask;
358                         mac.u[3] |= key->md.h3 & mask;
359                         mac.u[4] |= key->md.h4 & mask;
360
361 #ifdef BSWAP
362                         mac.u[0] = BSWAP(mac.u[0]);
363                         mac.u[1] = BSWAP(mac.u[1]);
364                         mac.u[2] = BSWAP(mac.u[2]);
365                         mac.u[3] = BSWAP(mac.u[3]);
366                         mac.u[4] = BSWAP(mac.u[4]);
367 #else
368                         for (i=0;i<5;i++) {
369                                 res = mac.u[i];
370                                 mac.c[4*i+0]=(unsigned char)(res>>24);
371                                 mac.c[4*i+1]=(unsigned char)(res>>16);
372                                 mac.c[4*i+2]=(unsigned char)(res>>8);
373                                 mac.c[4*i+3]=(unsigned char)res;
374                         }
375 #endif
376                         len += SHA_DIGEST_LENGTH;
377 #else
378                         SHA1_Update(&key->md,out,inp_len);
379                         res = key->md.num;
380                         SHA1_Final(mac.c,&key->md);
381
382                         {
383                         unsigned int inp_blocks, pad_blocks;
384
385                         /* but pretend as if we hashed padded payload */
386                         inp_blocks = 1+((SHA_CBLOCK-9-res)>>(sizeof(res)*8-1));
387                         res += (unsigned int)(len-inp_len);
388                         pad_blocks = res / SHA_CBLOCK;
389                         res %= SHA_CBLOCK;
390                         pad_blocks += 1+((SHA_CBLOCK-9-res)>>(sizeof(res)*8-1));
391                         for (;inp_blocks<pad_blocks;inp_blocks++)
392                                 sha1_block_data_order(&key->md,data,1);
393                         }
394 #endif
395                         key->md = key->tail;
396                         SHA1_Update(&key->md,mac.c,SHA_DIGEST_LENGTH);
397                         SHA1_Final(mac.c,&key->md);
398
399                         /* verify HMAC */
400                         out += inp_len;
401                         len -= inp_len;
402 #if 1
403                         {
404                         unsigned char *p = out+len-1-maxpad-SHA_DIGEST_LENGTH;
405                         size_t off = out-p;
406                         unsigned int c, cmask;
407
408                         maxpad += SHA_DIGEST_LENGTH;
409                         for (res=0,i=0,j=0;j<maxpad;j++) {
410                                 c = p[j];
411                                 cmask = ((int)(j-off-SHA_DIGEST_LENGTH))>>(sizeof(int)*8-1);
412                                 res |= (c^pad)&~cmask;  /* ... and padding */
413                                 cmask &= ((int)(off-1-j))>>(sizeof(int)*8-1);
414                                 res |= (c^mac.c[i])&cmask;
415                                 i += 1&cmask;
416                         }
417                         maxpad -= SHA_DIGEST_LENGTH;
418
419                         res = 0-((0-res)>>(sizeof(res)*8-1));
420                         ret &= (int)~res;
421                         }
422 #else
423                         for (res=0,i=0;i<SHA_DIGEST_LENGTH;i++)
424                                 res |= out[i]^mac.c[i];
425                         res = 0-((0-res)>>(sizeof(res)*8-1));
426                         ret &= (int)~res;
427
428                         /* verify padding */
429                         pad = (pad&~res) | (maxpad&res);
430                         out = out+len-1-pad;
431                         for (res=0,i=0;i<pad;i++)
432                                 res |= out[i]^pad;
433
434                         res = (0-res)>>(sizeof(res)*8-1);
435                         ret &= (int)~res;
436 #endif
437                         return ret;
438                 } else {
439                         SHA1_Update(&key->md,out,len);
440                 }
441         }
442
443         return 1;
444         }
445
446 static int aesni_cbc_hmac_sha1_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
447         {
448         EVP_AES_HMAC_SHA1 *key = data(ctx);
449
450         switch (type)
451                 {
452         case EVP_CTRL_AEAD_SET_MAC_KEY:
453                 {
454                 unsigned int  i;
455                 unsigned char hmac_key[64];
456
457                 memset (hmac_key,0,sizeof(hmac_key));
458
459                 if (arg > (int)sizeof(hmac_key)) {
460                         SHA1_Init(&key->head);
461                         SHA1_Update(&key->head,ptr,arg);
462                         SHA1_Final(hmac_key,&key->head);
463                 } else {
464                         memcpy(hmac_key,ptr,arg);
465                 }
466
467                 for (i=0;i<sizeof(hmac_key);i++)
468                         hmac_key[i] ^= 0x36;            /* ipad */
469                 SHA1_Init(&key->head);
470                 SHA1_Update(&key->head,hmac_key,sizeof(hmac_key));
471
472                 for (i=0;i<sizeof(hmac_key);i++)
473                         hmac_key[i] ^= 0x36^0x5c;       /* opad */
474                 SHA1_Init(&key->tail);
475                 SHA1_Update(&key->tail,hmac_key,sizeof(hmac_key));
476
477                 OPENSSL_cleanse(hmac_key,sizeof(hmac_key));
478
479                 return 1;
480                 }
481         case EVP_CTRL_AEAD_TLS1_AAD:
482                 {
483                 unsigned char *p=ptr;
484                 unsigned int   len=p[arg-2]<<8|p[arg-1];
485
486                 if (ctx->encrypt)
487                         {
488                         key->payload_length = len;
489                         if ((key->aux.tls_ver=p[arg-4]<<8|p[arg-3]) >= TLS1_1_VERSION) {
490                                 len -= AES_BLOCK_SIZE;
491                                 p[arg-2] = len>>8;
492                                 p[arg-1] = len;
493                         }
494                         key->md = key->head;
495                         SHA1_Update(&key->md,p,arg);
496
497                         return (int)(((len+SHA_DIGEST_LENGTH+AES_BLOCK_SIZE)&-AES_BLOCK_SIZE)
498                                 - len);
499                         }
500                 else
501                         {
502                         if (arg>13) arg = 13;
503                         memcpy(key->aux.tls_aad,ptr,arg);
504                         key->payload_length = arg;
505
506                         return SHA_DIGEST_LENGTH;
507                         }
508                 }
509         default:
510                 return -1;
511                 }
512         }
513
514 static EVP_CIPHER aesni_128_cbc_hmac_sha1_cipher =
515         {
516 #ifdef NID_aes_128_cbc_hmac_sha1
517         NID_aes_128_cbc_hmac_sha1,
518 #else
519         NID_undef,
520 #endif
521         16,16,16,
522         EVP_CIPH_CBC_MODE|EVP_CIPH_FLAG_DEFAULT_ASN1|EVP_CIPH_FLAG_AEAD_CIPHER,
523         aesni_cbc_hmac_sha1_init_key,
524         aesni_cbc_hmac_sha1_cipher,
525         NULL,
526         sizeof(EVP_AES_HMAC_SHA1),
527         EVP_CIPH_FLAG_DEFAULT_ASN1?NULL:EVP_CIPHER_set_asn1_iv,
528         EVP_CIPH_FLAG_DEFAULT_ASN1?NULL:EVP_CIPHER_get_asn1_iv,
529         aesni_cbc_hmac_sha1_ctrl,
530         NULL
531         };
532
533 static EVP_CIPHER aesni_256_cbc_hmac_sha1_cipher =
534         {
535 #ifdef NID_aes_256_cbc_hmac_sha1
536         NID_aes_256_cbc_hmac_sha1,
537 #else
538         NID_undef,
539 #endif
540         16,32,16,
541         EVP_CIPH_CBC_MODE|EVP_CIPH_FLAG_DEFAULT_ASN1|EVP_CIPH_FLAG_AEAD_CIPHER,
542         aesni_cbc_hmac_sha1_init_key,
543         aesni_cbc_hmac_sha1_cipher,
544         NULL,
545         sizeof(EVP_AES_HMAC_SHA1),
546         EVP_CIPH_FLAG_DEFAULT_ASN1?NULL:EVP_CIPHER_set_asn1_iv,
547         EVP_CIPH_FLAG_DEFAULT_ASN1?NULL:EVP_CIPHER_get_asn1_iv,
548         aesni_cbc_hmac_sha1_ctrl,
549         NULL
550         };
551
552 const EVP_CIPHER *EVP_aes_128_cbc_hmac_sha1(void)
553         {
554         return(OPENSSL_ia32cap_P[1]&AESNI_CAPABLE?
555                 &aesni_128_cbc_hmac_sha1_cipher:NULL);
556         }
557
558 const EVP_CIPHER *EVP_aes_256_cbc_hmac_sha1(void)
559         {
560         return(OPENSSL_ia32cap_P[1]&AESNI_CAPABLE?
561                 &aesni_256_cbc_hmac_sha1_cipher:NULL);
562         }
563 #else
564 const EVP_CIPHER *EVP_aes_128_cbc_hmac_sha1(void)
565         {
566         return NULL;
567         }
568 const EVP_CIPHER *EVP_aes_256_cbc_hmac_sha1(void)
569         {
570         return NULL;
571         }
572 #endif
573 #endif