xref: /freebsd/crypto/openssl/ssl/t1_enc.c (revision c4f6a2a9e1b1879b618c436ab4f56ff75c73a0f5)
1 /* ssl/t1_enc.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 /* ====================================================================
59  * Copyright (c) 1998-2002 The OpenSSL Project.  All rights reserved.
60  *
61  * Redistribution and use in source and binary forms, with or without
62  * modification, are permitted provided that the following conditions
63  * are met:
64  *
65  * 1. Redistributions of source code must retain the above copyright
66  *    notice, this list of conditions and the following disclaimer.
67  *
68  * 2. Redistributions in binary form must reproduce the above copyright
69  *    notice, this list of conditions and the following disclaimer in
70  *    the documentation and/or other materials provided with the
71  *    distribution.
72  *
73  * 3. All advertising materials mentioning features or use of this
74  *    software must display the following acknowledgment:
75  *    "This product includes software developed by the OpenSSL Project
76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77  *
78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79  *    endorse or promote products derived from this software without
80  *    prior written permission. For written permission, please contact
81  *    openssl-core@openssl.org.
82  *
83  * 5. Products derived from this software may not be called "OpenSSL"
84  *    nor may "OpenSSL" appear in their names without prior written
85  *    permission of the OpenSSL Project.
86  *
87  * 6. Redistributions of any form whatsoever must retain the following
88  *    acknowledgment:
89  *    "This product includes software developed by the OpenSSL Project
90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91  *
92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103  * OF THE POSSIBILITY OF SUCH DAMAGE.
104  * ====================================================================
105  *
106  * This product includes cryptographic software written by Eric Young
107  * (eay@cryptsoft.com).  This product includes software written by Tim
108  * Hudson (tjh@cryptsoft.com).
109  *
110  */
111 
112 #include <stdio.h>
113 #include <openssl/comp.h>
114 #include <openssl/md5.h>
115 #include <openssl/sha.h>
116 #include <openssl/evp.h>
117 #include <openssl/hmac.h>
118 #include "ssl_locl.h"
119 
120 static void tls1_P_hash(const EVP_MD *md, const unsigned char *sec,
121 			int sec_len, unsigned char *seed, int seed_len,
122 			unsigned char *out, int olen)
123 	{
124 	int chunk,n;
125 	unsigned int j;
126 	HMAC_CTX ctx;
127 	HMAC_CTX ctx_tmp;
128 	unsigned char A1[HMAC_MAX_MD_CBLOCK];
129 	unsigned int A1_len;
130 
131 	chunk=EVP_MD_size(md);
132 
133 	HMAC_Init(&ctx,sec,sec_len,md);
134 	HMAC_Update(&ctx,seed,seed_len);
135 	HMAC_Final(&ctx,A1,&A1_len);
136 
137 	n=0;
138 	for (;;)
139 		{
140 		HMAC_Init(&ctx,NULL,0,NULL); /* re-init */
141 		HMAC_Update(&ctx,A1,A1_len);
142 		memcpy(&ctx_tmp,&ctx,sizeof(ctx)); /* Copy for A2 */ /* not needed for last one */
143 		HMAC_Update(&ctx,seed,seed_len);
144 
145 		if (olen > chunk)
146 			{
147 			HMAC_Final(&ctx,out,&j);
148 			out+=j;
149 			olen-=j;
150 			HMAC_Final(&ctx_tmp,A1,&A1_len); /* calc the next A1 value */
151 			}
152 		else	/* last one */
153 			{
154 			HMAC_Final(&ctx,A1,&A1_len);
155 			memcpy(out,A1,olen);
156 			break;
157 			}
158 		}
159 	HMAC_cleanup(&ctx);
160 	HMAC_cleanup(&ctx_tmp);
161 	memset(A1,0,sizeof(A1));
162 	}
163 
164 static void tls1_PRF(const EVP_MD *md5, const EVP_MD *sha1,
165 		     unsigned char *label, int label_len,
166 		     const unsigned char *sec, int slen, unsigned char *out1,
167 		     unsigned char *out2, int olen)
168 	{
169 	int len,i;
170 	const unsigned char *S1,*S2;
171 
172 	len=slen/2;
173 	S1=sec;
174 	S2= &(sec[len]);
175 	len+=(slen&1); /* add for odd, make longer */
176 
177 
178 	tls1_P_hash(md5 ,S1,len,label,label_len,out1,olen);
179 	tls1_P_hash(sha1,S2,len,label,label_len,out2,olen);
180 
181 	for (i=0; i<olen; i++)
182 		out1[i]^=out2[i];
183 	}
184 
185 static void tls1_generate_key_block(SSL *s, unsigned char *km,
186 	     unsigned char *tmp, int num)
187 	{
188 	unsigned char *p;
189 	unsigned char buf[SSL3_RANDOM_SIZE*2+
190 		TLS_MD_MAX_CONST_SIZE];
191 	p=buf;
192 
193 	memcpy(p,TLS_MD_KEY_EXPANSION_CONST,
194 		TLS_MD_KEY_EXPANSION_CONST_SIZE);
195 	p+=TLS_MD_KEY_EXPANSION_CONST_SIZE;
196 	memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
197 	p+=SSL3_RANDOM_SIZE;
198 	memcpy(p,s->s3->client_random,SSL3_RANDOM_SIZE);
199 	p+=SSL3_RANDOM_SIZE;
200 
201 	tls1_PRF(s->ctx->md5,s->ctx->sha1,buf,(int)(p-buf),
202 		 s->session->master_key,s->session->master_key_length,
203 		 km,tmp,num);
204 	}
205 
206 int tls1_change_cipher_state(SSL *s, int which)
207 	{
208 	static const unsigned char empty[]="";
209 	unsigned char *p,*key_block,*mac_secret;
210 	unsigned char *exp_label,buf[TLS_MD_MAX_CONST_SIZE+
211 		SSL3_RANDOM_SIZE*2];
212 	unsigned char tmp1[EVP_MAX_KEY_LENGTH];
213 	unsigned char tmp2[EVP_MAX_KEY_LENGTH];
214 	unsigned char iv1[EVP_MAX_IV_LENGTH*2];
215 	unsigned char iv2[EVP_MAX_IV_LENGTH*2];
216 	unsigned char *ms,*key,*iv,*er1,*er2;
217 	int client_write;
218 	EVP_CIPHER_CTX *dd;
219 	const EVP_CIPHER *c;
220 	const SSL_COMP *comp;
221 	const EVP_MD *m;
222 	int _exp,n,i,j,k,exp_label_len,cl;
223 
224 	_exp=SSL_C_IS_EXPORT(s->s3->tmp.new_cipher);
225 	c=s->s3->tmp.new_sym_enc;
226 	m=s->s3->tmp.new_hash;
227 	comp=s->s3->tmp.new_compression;
228 	key_block=s->s3->tmp.key_block;
229 
230 	if (which & SSL3_CC_READ)
231 		{
232 		if ((s->enc_read_ctx == NULL) &&
233 			((s->enc_read_ctx=(EVP_CIPHER_CTX *)
234 			OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
235 			goto err;
236 		dd= s->enc_read_ctx;
237 		s->read_hash=m;
238 		if (s->expand != NULL)
239 			{
240 			COMP_CTX_free(s->expand);
241 			s->expand=NULL;
242 			}
243 		if (comp != NULL)
244 			{
245 			s->expand=COMP_CTX_new(comp->method);
246 			if (s->expand == NULL)
247 				{
248 				SSLerr(SSL_F_TLS1_CHANGE_CIPHER_STATE,SSL_R_COMPRESSION_LIBRARY_ERROR);
249 				goto err2;
250 				}
251 			if (s->s3->rrec.comp == NULL)
252 				s->s3->rrec.comp=(unsigned char *)
253 					OPENSSL_malloc(SSL3_RT_MAX_ENCRYPTED_LENGTH);
254 			if (s->s3->rrec.comp == NULL)
255 				goto err;
256 			}
257 		memset(&(s->s3->read_sequence[0]),0,8);
258 		mac_secret= &(s->s3->read_mac_secret[0]);
259 		}
260 	else
261 		{
262 		if ((s->enc_write_ctx == NULL) &&
263 			((s->enc_write_ctx=(EVP_CIPHER_CTX *)
264 			OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
265 			goto err;
266 		dd= s->enc_write_ctx;
267 		s->write_hash=m;
268 		if (s->compress != NULL)
269 			{
270 			COMP_CTX_free(s->compress);
271 			s->compress=NULL;
272 			}
273 		if (comp != NULL)
274 			{
275 			s->compress=COMP_CTX_new(comp->method);
276 			if (s->compress == NULL)
277 				{
278 				SSLerr(SSL_F_TLS1_CHANGE_CIPHER_STATE,SSL_R_COMPRESSION_LIBRARY_ERROR);
279 				goto err2;
280 				}
281 			}
282 		memset(&(s->s3->write_sequence[0]),0,8);
283 		mac_secret= &(s->s3->write_mac_secret[0]);
284 		}
285 
286 	EVP_CIPHER_CTX_init(dd);
287 
288 	p=s->s3->tmp.key_block;
289 	i=EVP_MD_size(m);
290 	cl=EVP_CIPHER_key_length(c);
291 	j=_exp ? (cl < SSL_C_EXPORT_KEYLENGTH(s->s3->tmp.new_cipher) ?
292 		  cl : SSL_C_EXPORT_KEYLENGTH(s->s3->tmp.new_cipher)) : cl;
293 	/* Was j=(exp)?5:EVP_CIPHER_key_length(c); */
294 	k=EVP_CIPHER_iv_length(c);
295 	er1= &(s->s3->client_random[0]);
296 	er2= &(s->s3->server_random[0]);
297 	if (	(which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
298 		(which == SSL3_CHANGE_CIPHER_SERVER_READ))
299 		{
300 		ms=  &(p[ 0]); n=i+i;
301 		key= &(p[ n]); n+=j+j;
302 		iv=  &(p[ n]); n+=k+k;
303 		exp_label=(unsigned char *)TLS_MD_CLIENT_WRITE_KEY_CONST;
304 		exp_label_len=TLS_MD_CLIENT_WRITE_KEY_CONST_SIZE;
305 		client_write=1;
306 		}
307 	else
308 		{
309 		n=i;
310 		ms=  &(p[ n]); n+=i+j;
311 		key= &(p[ n]); n+=j+k;
312 		iv=  &(p[ n]); n+=k;
313 		exp_label=(unsigned char *)TLS_MD_SERVER_WRITE_KEY_CONST;
314 		exp_label_len=TLS_MD_SERVER_WRITE_KEY_CONST_SIZE;
315 		client_write=0;
316 		}
317 
318 	if (n > s->s3->tmp.key_block_length)
319 		{
320 		SSLerr(SSL_F_TLS1_CHANGE_CIPHER_STATE,SSL_R_INTERNAL_ERROR);
321 		goto err2;
322 		}
323 
324 	memcpy(mac_secret,ms,i);
325 #ifdef TLS_DEBUG
326 printf("which = %04X\nmac key=",which);
327 { int z; for (z=0; z<i; z++) printf("%02X%c",ms[z],((z+1)%16)?' ':'\n'); }
328 #endif
329 	if (_exp)
330 		{
331 		/* In here I set both the read and write key/iv to the
332 		 * same value since only the correct one will be used :-).
333 		 */
334 		p=buf;
335 		memcpy(p,exp_label,exp_label_len);
336 		p+=exp_label_len;
337 		memcpy(p,s->s3->client_random,SSL3_RANDOM_SIZE);
338 		p+=SSL3_RANDOM_SIZE;
339 		memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
340 		p+=SSL3_RANDOM_SIZE;
341 		tls1_PRF(s->ctx->md5,s->ctx->sha1,buf,(int)(p-buf),key,j,
342 			 tmp1,tmp2,EVP_CIPHER_key_length(c));
343 		key=tmp1;
344 
345 		if (k > 0)
346 			{
347 			p=buf;
348 			memcpy(p,TLS_MD_IV_BLOCK_CONST,
349 				TLS_MD_IV_BLOCK_CONST_SIZE);
350 			p+=TLS_MD_IV_BLOCK_CONST_SIZE;
351 			memcpy(p,s->s3->client_random,SSL3_RANDOM_SIZE);
352 			p+=SSL3_RANDOM_SIZE;
353 			memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
354 			p+=SSL3_RANDOM_SIZE;
355 			tls1_PRF(s->ctx->md5,s->ctx->sha1,buf,p-buf,empty,0,
356 				 iv1,iv2,k*2);
357 			if (client_write)
358 				iv=iv1;
359 			else
360 				iv= &(iv1[k]);
361 			}
362 		}
363 
364 	s->session->key_arg_length=0;
365 
366 	EVP_CipherInit(dd,c,key,iv,(which & SSL3_CC_WRITE));
367 #ifdef TLS_DEBUG
368 printf("which = %04X\nkey=",which);
369 { int z; for (z=0; z<EVP_CIPHER_key_length(c); z++) printf("%02X%c",key[z],((z+1)%16)?' ':'\n'); }
370 printf("\niv=");
371 { int z; for (z=0; z<k; z++) printf("%02X%c",iv[z],((z+1)%16)?' ':'\n'); }
372 printf("\n");
373 #endif
374 
375 	memset(tmp1,0,sizeof(tmp1));
376 	memset(tmp2,0,sizeof(tmp1));
377 	memset(iv1,0,sizeof(iv1));
378 	memset(iv2,0,sizeof(iv2));
379 	return(1);
380 err:
381 	SSLerr(SSL_F_TLS1_CHANGE_CIPHER_STATE,ERR_R_MALLOC_FAILURE);
382 err2:
383 	return(0);
384 	}
385 
386 int tls1_setup_key_block(SSL *s)
387 	{
388 	unsigned char *p1,*p2;
389 	const EVP_CIPHER *c;
390 	const EVP_MD *hash;
391 	int num;
392 	SSL_COMP *comp;
393 
394 	if (s->s3->tmp.key_block_length != 0)
395 		return(1);
396 
397 	if (!ssl_cipher_get_evp(s->session,&c,&hash,&comp))
398 		{
399 		SSLerr(SSL_F_TLS1_SETUP_KEY_BLOCK,SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
400 		return(0);
401 		}
402 
403 	s->s3->tmp.new_sym_enc=c;
404 	s->s3->tmp.new_hash=hash;
405 
406 	num=EVP_CIPHER_key_length(c)+EVP_MD_size(hash)+EVP_CIPHER_iv_length(c);
407 	num*=2;
408 
409 	ssl3_cleanup_key_block(s);
410 
411 	if ((p1=(unsigned char *)OPENSSL_malloc(num)) == NULL)
412 		goto err;
413 	if ((p2=(unsigned char *)OPENSSL_malloc(num)) == NULL)
414 		goto err;
415 
416 	s->s3->tmp.key_block_length=num;
417 	s->s3->tmp.key_block=p1;
418 
419 
420 #ifdef TLS_DEBUG
421 printf("client random\n");
422 { int z; for (z=0; z<SSL3_RANDOM_SIZE; z++) printf("%02X%c",s->s3->client_random[z],((z+1)%16)?' ':'\n'); }
423 printf("server random\n");
424 { int z; for (z=0; z<SSL3_RANDOM_SIZE; z++) printf("%02X%c",s->s3->server_random[z],((z+1)%16)?' ':'\n'); }
425 printf("pre-master\n");
426 { int z; for (z=0; z<s->session->master_key_length; z++) printf("%02X%c",s->session->master_key[z],((z+1)%16)?' ':'\n'); }
427 #endif
428 	tls1_generate_key_block(s,p1,p2,num);
429 	memset(p2,0,num);
430 	OPENSSL_free(p2);
431 #ifdef TLS_DEBUG
432 printf("\nkey block\n");
433 { int z; for (z=0; z<num; z++) printf("%02X%c",p1[z],((z+1)%16)?' ':'\n'); }
434 #endif
435 
436 	if (!(s->options & SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS))
437 		{
438 		/* enable vulnerability countermeasure for CBC ciphers with
439 		 * known-IV problem (http://www.openssl.org/~bodo/tls-cbc.txt)
440 		 */
441 		s->s3->need_empty_fragments = 1;
442 
443 		if (s->session->cipher != NULL)
444 			{
445 			if ((s->session->cipher->algorithms & SSL_ENC_MASK) == SSL_eNULL)
446 				s->s3->need_empty_fragments = 0;
447 
448 #ifndef NO_RC4
449 			if ((s->session->cipher->algorithms & SSL_ENC_MASK) == SSL_RC4)
450 				s->s3->need_empty_fragments = 0;
451 #endif
452 			}
453 		}
454 
455 	return(1);
456 err:
457 	SSLerr(SSL_F_TLS1_SETUP_KEY_BLOCK,ERR_R_MALLOC_FAILURE);
458 	return(0);
459 	}
460 
461 int tls1_enc(SSL *s, int send)
462 	{
463 	SSL3_RECORD *rec;
464 	EVP_CIPHER_CTX *ds;
465 	unsigned long l;
466 	int bs,i,ii,j,k,n=0;
467 	const EVP_CIPHER *enc;
468 
469 	if (send)
470 		{
471 		if (s->write_hash != NULL)
472 			n=EVP_MD_size(s->write_hash);
473 		ds=s->enc_write_ctx;
474 		rec= &(s->s3->wrec);
475 		if (s->enc_write_ctx == NULL)
476 			enc=NULL;
477 		else
478 			enc=EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
479 		}
480 	else
481 		{
482 		if (s->read_hash != NULL)
483 			n=EVP_MD_size(s->read_hash);
484 		ds=s->enc_read_ctx;
485 		rec= &(s->s3->rrec);
486 		if (s->enc_read_ctx == NULL)
487 			enc=NULL;
488 		else
489 			enc=EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
490 		}
491 
492 	if ((s->session == NULL) || (ds == NULL) ||
493 		(enc == NULL))
494 		{
495 		memmove(rec->data,rec->input,rec->length);
496 		rec->input=rec->data;
497 		}
498 	else
499 		{
500 		l=rec->length;
501 		bs=EVP_CIPHER_block_size(ds->cipher);
502 
503 		if ((bs != 1) && send)
504 			{
505 			i=bs-((int)l%bs);
506 
507 			/* Add weird padding of upto 256 bytes */
508 
509 			/* we need to add 'i' padding bytes of value j */
510 			j=i-1;
511 			if (s->options & SSL_OP_TLS_BLOCK_PADDING_BUG)
512 				{
513 				if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
514 					j++;
515 				}
516 			for (k=(int)l; k<(int)(l+i); k++)
517 				rec->input[k]=j;
518 			l+=i;
519 			rec->length+=i;
520 			}
521 
522 		if (!send)
523 			{
524 			if (l == 0 || l%bs != 0)
525 				{
526 				SSLerr(SSL_F_TLS1_ENC,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
527 				ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_DECRYPTION_FAILED);
528 				return 0;
529 				}
530 			}
531 
532 		EVP_Cipher(ds,rec->data,rec->input,l);
533 
534 		if ((bs != 1) && !send)
535 			{
536 			ii=i=rec->data[l-1]; /* padding_length */
537 			i++;
538 			if (s->options&SSL_OP_TLS_BLOCK_PADDING_BUG)
539 				{
540 				/* First packet is even in size, so check */
541 				if ((memcmp(s->s3->read_sequence,
542 					"\0\0\0\0\0\0\0\0",8) == 0) && !(ii & 1))
543 					s->s3->flags|=TLS1_FLAGS_TLS_PADDING_BUG;
544 				if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
545 					i--;
546 				}
547 			/* TLS 1.0 does not bound the number of padding bytes by the block size.
548 			 * All of them must have value 'padding_length'. */
549 			if (i > (int)rec->length)
550 				{
551 				/* Incorrect padding. SSLerr() and ssl3_alert are done
552 				 * by caller: we don't want to reveal whether this is
553 				 * a decryption error or a MAC verification failure
554 				 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
555 				return -1;
556 				}
557 			for (j=(int)(l-i); j<(int)l; j++)
558 				{
559 				if (rec->data[j] != ii)
560 					{
561 					/* Incorrect padding */
562 					return -1;
563 					}
564 				}
565 			rec->length-=i;
566 			}
567 		}
568 	return(1);
569 	}
570 
571 int tls1_cert_verify_mac(SSL *s, EVP_MD_CTX *in_ctx, unsigned char *out)
572 	{
573 	unsigned int ret;
574 	EVP_MD_CTX ctx;
575 
576 	EVP_MD_CTX_copy(&ctx,in_ctx);
577 	EVP_DigestFinal(&ctx,out,&ret);
578 	return((int)ret);
579 	}
580 
581 int tls1_final_finish_mac(SSL *s, EVP_MD_CTX *in1_ctx, EVP_MD_CTX *in2_ctx,
582 	     const char *str, int slen, unsigned char *out)
583 	{
584 	unsigned int i;
585 	EVP_MD_CTX ctx;
586 	unsigned char buf[TLS_MD_MAX_CONST_SIZE+MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
587 	unsigned char *q,buf2[12];
588 
589 	q=buf;
590 	memcpy(q,str,slen);
591 	q+=slen;
592 
593 	EVP_MD_CTX_copy(&ctx,in1_ctx);
594 	EVP_DigestFinal(&ctx,q,&i);
595 	q+=i;
596 	EVP_MD_CTX_copy(&ctx,in2_ctx);
597 	EVP_DigestFinal(&ctx,q,&i);
598 	q+=i;
599 
600 	tls1_PRF(s->ctx->md5,s->ctx->sha1,buf,(int)(q-buf),
601 		s->session->master_key,s->session->master_key_length,
602 		out,buf2,12);
603 	memset(&ctx,0,sizeof(EVP_MD_CTX));
604 
605 	return((int)12);
606 	}
607 
608 int tls1_mac(SSL *ssl, unsigned char *md, int send)
609 	{
610 	SSL3_RECORD *rec;
611 	unsigned char *mac_sec,*seq;
612 	const EVP_MD *hash;
613 	unsigned int md_size;
614 	int i;
615 	HMAC_CTX hmac;
616 	unsigned char buf[5];
617 
618 	if (send)
619 		{
620 		rec= &(ssl->s3->wrec);
621 		mac_sec= &(ssl->s3->write_mac_secret[0]);
622 		seq= &(ssl->s3->write_sequence[0]);
623 		hash=ssl->write_hash;
624 		}
625 	else
626 		{
627 		rec= &(ssl->s3->rrec);
628 		mac_sec= &(ssl->s3->read_mac_secret[0]);
629 		seq= &(ssl->s3->read_sequence[0]);
630 		hash=ssl->read_hash;
631 		}
632 
633 	md_size=EVP_MD_size(hash);
634 
635 	buf[0]=rec->type;
636 	buf[1]=TLS1_VERSION_MAJOR;
637 	buf[2]=TLS1_VERSION_MINOR;
638 	buf[3]=rec->length>>8;
639 	buf[4]=rec->length&0xff;
640 
641 	/* I should fix this up TLS TLS TLS TLS TLS XXXXXXXX */
642 	HMAC_Init(&hmac,mac_sec,EVP_MD_size(hash),hash);
643 	HMAC_Update(&hmac,seq,8);
644 	HMAC_Update(&hmac,buf,5);
645 	HMAC_Update(&hmac,rec->input,rec->length);
646 	HMAC_Final(&hmac,md,&md_size);
647 
648 #ifdef TLS_DEBUG
649 printf("sec=");
650 {unsigned int z; for (z=0; z<md_size; z++) printf("%02X ",mac_sec[z]); printf("\n"); }
651 printf("seq=");
652 {int z; for (z=0; z<8; z++) printf("%02X ",seq[z]); printf("\n"); }
653 printf("buf=");
654 {int z; for (z=0; z<5; z++) printf("%02X ",buf[z]); printf("\n"); }
655 printf("rec=");
656 {unsigned int z; for (z=0; z<rec->length; z++) printf("%02X ",buf[z]); printf("\n"); }
657 #endif
658 
659 	for (i=7; i>=0; i--)
660 		{
661 		++seq[i];
662 		if (seq[i] != 0) break;
663 		}
664 
665 #ifdef TLS_DEBUG
666 {unsigned int z; for (z=0; z<md_size; z++) printf("%02X ",md[z]); printf("\n"); }
667 #endif
668 	return(md_size);
669 	}
670 
671 int tls1_generate_master_secret(SSL *s, unsigned char *out, unsigned char *p,
672 	     int len)
673 	{
674 	unsigned char buf[SSL3_RANDOM_SIZE*2+TLS_MD_MASTER_SECRET_CONST_SIZE];
675 	unsigned char buff[SSL_MAX_MASTER_KEY_LENGTH];
676 
677 	/* Setup the stuff to munge */
678 	memcpy(buf,TLS_MD_MASTER_SECRET_CONST,
679 		TLS_MD_MASTER_SECRET_CONST_SIZE);
680 	memcpy(&(buf[TLS_MD_MASTER_SECRET_CONST_SIZE]),
681 		s->s3->client_random,SSL3_RANDOM_SIZE);
682 	memcpy(&(buf[SSL3_RANDOM_SIZE+TLS_MD_MASTER_SECRET_CONST_SIZE]),
683 		s->s3->server_random,SSL3_RANDOM_SIZE);
684 	tls1_PRF(s->ctx->md5,s->ctx->sha1,
685 		buf,TLS_MD_MASTER_SECRET_CONST_SIZE+SSL3_RANDOM_SIZE*2,p,len,
686 		s->session->master_key,buff,SSL3_MASTER_SECRET_SIZE);
687 	return(SSL3_MASTER_SECRET_SIZE);
688 	}
689 
690 int tls1_alert_code(int code)
691 	{
692 	switch (code)
693 		{
694 	case SSL_AD_CLOSE_NOTIFY:	return(SSL3_AD_CLOSE_NOTIFY);
695 	case SSL_AD_UNEXPECTED_MESSAGE:	return(SSL3_AD_UNEXPECTED_MESSAGE);
696 	case SSL_AD_BAD_RECORD_MAC:	return(SSL3_AD_BAD_RECORD_MAC);
697 	case SSL_AD_DECRYPTION_FAILED:	return(TLS1_AD_DECRYPTION_FAILED);
698 	case SSL_AD_RECORD_OVERFLOW:	return(TLS1_AD_RECORD_OVERFLOW);
699 	case SSL_AD_DECOMPRESSION_FAILURE:return(SSL3_AD_DECOMPRESSION_FAILURE);
700 	case SSL_AD_HANDSHAKE_FAILURE:	return(SSL3_AD_HANDSHAKE_FAILURE);
701 	case SSL_AD_NO_CERTIFICATE:	return(-1);
702 	case SSL_AD_BAD_CERTIFICATE:	return(SSL3_AD_BAD_CERTIFICATE);
703 	case SSL_AD_UNSUPPORTED_CERTIFICATE:return(SSL3_AD_UNSUPPORTED_CERTIFICATE);
704 	case SSL_AD_CERTIFICATE_REVOKED:return(SSL3_AD_CERTIFICATE_REVOKED);
705 	case SSL_AD_CERTIFICATE_EXPIRED:return(SSL3_AD_CERTIFICATE_EXPIRED);
706 	case SSL_AD_CERTIFICATE_UNKNOWN:return(SSL3_AD_CERTIFICATE_UNKNOWN);
707 	case SSL_AD_ILLEGAL_PARAMETER:	return(SSL3_AD_ILLEGAL_PARAMETER);
708 	case SSL_AD_UNKNOWN_CA:		return(TLS1_AD_UNKNOWN_CA);
709 	case SSL_AD_ACCESS_DENIED:	return(TLS1_AD_ACCESS_DENIED);
710 	case SSL_AD_DECODE_ERROR:	return(TLS1_AD_DECODE_ERROR);
711 	case SSL_AD_DECRYPT_ERROR:	return(TLS1_AD_DECRYPT_ERROR);
712 	case SSL_AD_EXPORT_RESTRICTION:	return(TLS1_AD_EXPORT_RESTRICTION);
713 	case SSL_AD_PROTOCOL_VERSION:	return(TLS1_AD_PROTOCOL_VERSION);
714 	case SSL_AD_INSUFFICIENT_SECURITY:return(TLS1_AD_INSUFFICIENT_SECURITY);
715 	case SSL_AD_INTERNAL_ERROR:	return(TLS1_AD_INTERNAL_ERROR);
716 	case SSL_AD_USER_CANCELLED:	return(TLS1_AD_USER_CANCELLED);
717 	case SSL_AD_NO_RENEGOTIATION:	return(TLS1_AD_NO_RENEGOTIATION);
718 	default:			return(-1);
719 		}
720 	}
721 
722