7bb04e6f8ede2ebc587e0bbeda510909102c1374
[openssl.git] / ssl / t1_enc.c
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 #include <stdio.h>
60 #include <openssl/comp.h>
61 #include <openssl/evp.h>
62 #include <openssl/hmac.h>
63 #include "ssl_locl.h"
64 #include <openssl/md5.h>
65
66 static void tls1_P_hash(const EVP_MD *md, const unsigned char *sec,
67                         int sec_len, unsigned char *seed, int seed_len,
68                         unsigned char *out, int olen)
69         {
70         int chunk,n;
71         unsigned int j;
72         HMAC_CTX ctx;
73         HMAC_CTX ctx_tmp;
74         unsigned char A1[HMAC_MAX_MD_CBLOCK];
75         unsigned int A1_len;
76         
77         chunk=EVP_MD_size(md);
78
79         HMAC_CTX_init(&ctx);
80         HMAC_CTX_init(&ctx_tmp);
81         HMAC_Init(&ctx,sec,sec_len,md);
82         HMAC_Init(&ctx_tmp,sec,sec_len,md);
83         HMAC_Update(&ctx,seed,seed_len);
84         HMAC_Final(&ctx,A1,&A1_len);
85
86         n=0;
87         for (;;)
88                 {
89                 HMAC_Init(&ctx,NULL,0,NULL); /* re-init */
90                 HMAC_Init(&ctx_tmp,NULL,0,NULL); /* re-init */
91                 HMAC_Update(&ctx,A1,A1_len);
92                 HMAC_Update(&ctx_tmp,A1,A1_len);
93                 HMAC_Update(&ctx,seed,seed_len);
94
95                 if (olen > chunk)
96                         {
97                         HMAC_Final(&ctx,out,&j);
98                         out+=j;
99                         olen-=j;
100                         HMAC_Final(&ctx_tmp,A1,&A1_len); /* calc the next A1 value */
101                         }
102                 else    /* last one */
103                         {
104                         HMAC_Final(&ctx,A1,&A1_len);
105                         memcpy(out,A1,olen);
106                         break;
107                         }
108                 }
109         HMAC_CTX_cleanup(&ctx);
110         HMAC_CTX_cleanup(&ctx_tmp);
111         memset(A1,0,sizeof(A1));
112         }
113
114 static void tls1_PRF(const EVP_MD *md5, const EVP_MD *sha1,
115                      unsigned char *label, int label_len,
116                      const unsigned char *sec, int slen, unsigned char *out1,
117                      unsigned char *out2, int olen)
118         {
119         int len,i;
120         const unsigned char *S1,*S2;
121
122         len=slen/2;
123         S1=sec;
124         S2= &(sec[len]);
125         len+=(slen&1); /* add for odd, make longer */
126
127         
128         tls1_P_hash(md5 ,S1,len,label,label_len,out1,olen);
129         tls1_P_hash(sha1,S2,len,label,label_len,out2,olen);
130
131         for (i=0; i<olen; i++)
132                 out1[i]^=out2[i];
133         }
134
135 static void tls1_generate_key_block(SSL *s, unsigned char *km,
136              unsigned char *tmp, int num)
137         {
138         unsigned char *p;
139         unsigned char buf[SSL3_RANDOM_SIZE*2+
140                 TLS_MD_MAX_CONST_SIZE];
141         p=buf;
142
143         memcpy(p,TLS_MD_KEY_EXPANSION_CONST,
144                 TLS_MD_KEY_EXPANSION_CONST_SIZE);
145         p+=TLS_MD_KEY_EXPANSION_CONST_SIZE;
146         memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
147         p+=SSL3_RANDOM_SIZE;
148         memcpy(p,s->s3->client_random,SSL3_RANDOM_SIZE);
149         p+=SSL3_RANDOM_SIZE;
150
151         tls1_PRF(s->ctx->md5,s->ctx->sha1,buf,(int)(p-buf),
152                  s->session->master_key,s->session->master_key_length,
153                  km,tmp,num);
154 #ifdef KSSL_DEBUG
155         printf("tls1_generate_key_block() ==> %d byte master_key =\n\t",
156                 s->session->master_key_length);
157         {
158         int i;
159         for (i=0; i < s->session->master_key_length; i++)
160                 {
161                 printf("%02X", s->session->master_key[i]);
162                 }
163         printf("\n");  }
164 #endif    /* KSSL_DEBUG */
165         }
166
167 int tls1_change_cipher_state(SSL *s, int which)
168         {
169         static const unsigned char empty[]="";
170         unsigned char *p,*key_block,*mac_secret;
171         unsigned char *exp_label,buf[TLS_MD_MAX_CONST_SIZE+
172                 SSL3_RANDOM_SIZE*2];
173         unsigned char tmp1[EVP_MAX_KEY_LENGTH];
174         unsigned char tmp2[EVP_MAX_KEY_LENGTH];
175         unsigned char iv1[EVP_MAX_IV_LENGTH*2];
176         unsigned char iv2[EVP_MAX_IV_LENGTH*2];
177         unsigned char *ms,*key,*iv,*er1,*er2;
178         int client_write;
179         EVP_CIPHER_CTX *dd;
180         const EVP_CIPHER *c;
181         const SSL_COMP *comp;
182         const EVP_MD *m;
183         int _exp,n,i,j,k,exp_label_len,cl;
184
185         _exp=SSL_C_IS_EXPORT(s->s3->tmp.new_cipher);
186         c=s->s3->tmp.new_sym_enc;
187         m=s->s3->tmp.new_hash;
188         comp=s->s3->tmp.new_compression;
189         key_block=s->s3->tmp.key_block;
190
191 #ifdef KSSL_DEBUG
192         printf("tls1_change_cipher_state(which= %d) w/\n", which);
193         printf("\talg= %ld, comp= %p\n", s->s3->tmp.new_cipher->algorithms,
194                 comp);
195         printf("\tevp_cipher == %p ==? &d_cbc_ede_cipher3\n", c);
196         printf("\tevp_cipher: nid, blksz= %d, %d, keylen=%d, ivlen=%d\n",
197                 c->nid,c->block_size,c->key_len,c->iv_len);
198         printf("\tkey_block: len= %d, data= ", s->s3->tmp.key_block_length);
199         {
200         int i;
201         for (i=0; i<s->s3->tmp.key_block_length; i++)
202                 printf("%02x", key_block[i]);  printf("\n");
203         }
204 #endif  /* KSSL_DEBUG */
205
206         if (which & SSL3_CC_READ)
207                 {
208                 if ((s->enc_read_ctx == NULL) &&
209                         ((s->enc_read_ctx=(EVP_CIPHER_CTX *)
210                         OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
211                         goto err;
212                 dd= s->enc_read_ctx;
213                 s->read_hash=m;
214                 if (s->expand != NULL)
215                         {
216                         COMP_CTX_free(s->expand);
217                         s->expand=NULL;
218                         }
219                 if (comp != NULL)
220                         {
221                         s->expand=COMP_CTX_new(comp->method);
222                         if (s->expand == NULL)
223                                 {
224                                 SSLerr(SSL_F_TLS1_CHANGE_CIPHER_STATE,SSL_R_COMPRESSION_LIBRARY_ERROR);
225                                 goto err2;
226                                 }
227                         if (s->s3->rrec.comp == NULL)
228                                 s->s3->rrec.comp=(unsigned char *)
229                                         OPENSSL_malloc(SSL3_RT_MAX_ENCRYPTED_LENGTH);
230                         if (s->s3->rrec.comp == NULL)
231                                 goto err;
232                         }
233                 memset(&(s->s3->read_sequence[0]),0,8);
234                 mac_secret= &(s->s3->read_mac_secret[0]);
235                 }
236         else
237                 {
238                 if ((s->enc_write_ctx == NULL) &&
239                         ((s->enc_write_ctx=(EVP_CIPHER_CTX *)
240                         OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
241                         goto err;
242                 dd= s->enc_write_ctx;
243                 s->write_hash=m;
244                 if (s->compress != NULL)
245                         {
246                         COMP_CTX_free(s->compress);
247                         s->compress=NULL;
248                         }
249                 if (comp != NULL)
250                         {
251                         s->compress=COMP_CTX_new(comp->method);
252                         if (s->compress == NULL)
253                                 {
254                                 SSLerr(SSL_F_TLS1_CHANGE_CIPHER_STATE,SSL_R_COMPRESSION_LIBRARY_ERROR);
255                                 goto err2;
256                                 }
257                         }
258                 memset(&(s->s3->write_sequence[0]),0,8);
259                 mac_secret= &(s->s3->write_mac_secret[0]);
260                 }
261
262         EVP_CIPHER_CTX_init(dd);
263
264         p=s->s3->tmp.key_block;
265         i=EVP_MD_size(m);
266         cl=EVP_CIPHER_key_length(c);
267         j=_exp ? (cl < SSL_C_EXPORT_KEYLENGTH(s->s3->tmp.new_cipher) ?
268                   cl : SSL_C_EXPORT_KEYLENGTH(s->s3->tmp.new_cipher)) : cl;
269         /* Was j=(exp)?5:EVP_CIPHER_key_length(c); */
270         k=EVP_CIPHER_iv_length(c);
271         er1= &(s->s3->client_random[0]);
272         er2= &(s->s3->server_random[0]);
273         if (    (which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
274                 (which == SSL3_CHANGE_CIPHER_SERVER_READ))
275                 {
276                 ms=  &(p[ 0]); n=i+i;
277                 key= &(p[ n]); n+=j+j;
278                 iv=  &(p[ n]); n+=k+k;
279                 exp_label=(unsigned char *)TLS_MD_CLIENT_WRITE_KEY_CONST;
280                 exp_label_len=TLS_MD_CLIENT_WRITE_KEY_CONST_SIZE;
281                 client_write=1;
282                 }
283         else
284                 {
285                 n=i;
286                 ms=  &(p[ n]); n+=i+j;
287                 key= &(p[ n]); n+=j+k;
288                 iv=  &(p[ n]); n+=k;
289                 exp_label=(unsigned char *)TLS_MD_SERVER_WRITE_KEY_CONST;
290                 exp_label_len=TLS_MD_SERVER_WRITE_KEY_CONST_SIZE;
291                 client_write=0;
292                 }
293
294         if (n > s->s3->tmp.key_block_length)
295                 {
296                 SSLerr(SSL_F_TLS1_CHANGE_CIPHER_STATE,ERR_R_INTERNAL_ERROR);
297                 goto err2;
298                 }
299
300         memcpy(mac_secret,ms,i);
301 #ifdef TLS_DEBUG
302 printf("which = %04X\nmac key=",which);
303 { int z; for (z=0; z<i; z++) printf("%02X%c",ms[z],((z+1)%16)?' ':'\n'); }
304 #endif
305         if (_exp)
306                 {
307                 /* In here I set both the read and write key/iv to the
308                  * same value since only the correct one will be used :-).
309                  */
310                 p=buf;
311                 memcpy(p,exp_label,exp_label_len);
312                 p+=exp_label_len;
313                 memcpy(p,s->s3->client_random,SSL3_RANDOM_SIZE);
314                 p+=SSL3_RANDOM_SIZE;
315                 memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
316                 p+=SSL3_RANDOM_SIZE;
317                 tls1_PRF(s->ctx->md5,s->ctx->sha1,buf,(int)(p-buf),key,j,
318                          tmp1,tmp2,EVP_CIPHER_key_length(c));
319                 key=tmp1;
320
321                 if (k > 0)
322                         {
323                         p=buf;
324                         memcpy(p,TLS_MD_IV_BLOCK_CONST,
325                                 TLS_MD_IV_BLOCK_CONST_SIZE);
326                         p+=TLS_MD_IV_BLOCK_CONST_SIZE;
327                         memcpy(p,s->s3->client_random,SSL3_RANDOM_SIZE);
328                         p+=SSL3_RANDOM_SIZE;
329                         memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
330                         p+=SSL3_RANDOM_SIZE;
331                         tls1_PRF(s->ctx->md5,s->ctx->sha1,buf,p-buf,empty,0,
332                                  iv1,iv2,k*2);
333                         if (client_write)
334                                 iv=iv1;
335                         else
336                                 iv= &(iv1[k]);
337                         }
338                 }
339
340         s->session->key_arg_length=0;
341 #ifdef KSSL_DEBUG
342         {
343         int i;
344         printf("EVP_CipherInit_ex(dd,c,key=,iv=,which)\n");
345         printf("\tkey= "); for (i=0; i<c->key_len; i++) printf("%02x", key[i]);
346         printf("\n");
347         printf("\t iv= "); for (i=0; i<c->iv_len; i++) printf("%02x", iv[i]);
348         printf("\n");
349         }
350 #endif  /* KSSL_DEBUG */
351
352         EVP_CipherInit_ex(dd,c,NULL,key,iv,(which & SSL3_CC_WRITE));
353 #ifdef TLS_DEBUG
354 printf("which = %04X\nkey=",which);
355 { int z; for (z=0; z<EVP_CIPHER_key_length(c); z++) printf("%02X%c",key[z],((z+1)%16)?' ':'\n'); }
356 printf("\niv=");
357 { int z; for (z=0; z<k; z++) printf("%02X%c",iv[z],((z+1)%16)?' ':'\n'); }
358 printf("\n");
359 #endif
360
361         memset(tmp1,0,sizeof(tmp1));
362         memset(tmp2,0,sizeof(tmp1));
363         memset(iv1,0,sizeof(iv1));
364         memset(iv2,0,sizeof(iv2));
365         return(1);
366 err:
367         SSLerr(SSL_F_TLS1_CHANGE_CIPHER_STATE,ERR_R_MALLOC_FAILURE);
368 err2:
369         return(0);
370         }
371
372 int tls1_setup_key_block(SSL *s)
373         {
374         unsigned char *p1,*p2;
375         const EVP_CIPHER *c;
376         const EVP_MD *hash;
377         int num;
378         SSL_COMP *comp;
379
380 #ifdef KSSL_DEBUG
381         printf ("tls1_setup_key_block()\n");
382 #endif  /* KSSL_DEBUG */
383
384         if (s->s3->tmp.key_block_length != 0)
385                 return(1);
386
387         if (!ssl_cipher_get_evp(s->session,&c,&hash,&comp))
388                 {
389                 SSLerr(SSL_F_TLS1_SETUP_KEY_BLOCK,SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
390                 return(0);
391                 }
392
393         s->s3->tmp.new_sym_enc=c;
394         s->s3->tmp.new_hash=hash;
395
396         num=EVP_CIPHER_key_length(c)+EVP_MD_size(hash)+EVP_CIPHER_iv_length(c);
397         num*=2;
398
399         ssl3_cleanup_key_block(s);
400
401         if ((p1=(unsigned char *)OPENSSL_malloc(num)) == NULL)
402                 goto err;
403         if ((p2=(unsigned char *)OPENSSL_malloc(num)) == NULL)
404                 goto err;
405
406         s->s3->tmp.key_block_length=num;
407         s->s3->tmp.key_block=p1;
408
409
410 #ifdef TLS_DEBUG
411 printf("client random\n");
412 { int z; for (z=0; z<SSL3_RANDOM_SIZE; z++) printf("%02X%c",s->s3->client_random[z],((z+1)%16)?' ':'\n'); }
413 printf("server random\n");
414 { int z; for (z=0; z<SSL3_RANDOM_SIZE; z++) printf("%02X%c",s->s3->server_random[z],((z+1)%16)?' ':'\n'); }
415 printf("pre-master\n");
416 { int z; for (z=0; z<s->session->master_key_length; z++) printf("%02X%c",s->session->master_key[z],((z+1)%16)?' ':'\n'); }
417 #endif
418         tls1_generate_key_block(s,p1,p2,num);
419         memset(p2,0,num);
420         OPENSSL_free(p2);
421 #ifdef TLS_DEBUG
422 printf("\nkey block\n");
423 { int z; for (z=0; z<num; z++) printf("%02X%c",p1[z],((z+1)%16)?' ':'\n'); }
424 #endif
425
426         return(1);
427 err:
428         SSLerr(SSL_F_TLS1_SETUP_KEY_BLOCK,ERR_R_MALLOC_FAILURE);
429         return(0);
430         }
431
432 int tls1_enc(SSL *s, int send)
433         {
434         SSL3_RECORD *rec;
435         EVP_CIPHER_CTX *ds;
436         unsigned long l;
437         int bs,i,ii,j,k,n=0;
438         const EVP_CIPHER *enc;
439
440         if (send)
441                 {
442                 if (s->write_hash != NULL)
443                         n=EVP_MD_size(s->write_hash);
444                 ds=s->enc_write_ctx;
445                 rec= &(s->s3->wrec);
446                 if (s->enc_write_ctx == NULL)
447                         enc=NULL;
448                 else
449                         enc=EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
450                 }
451         else
452                 {
453                 if (s->read_hash != NULL)
454                         n=EVP_MD_size(s->read_hash);
455                 ds=s->enc_read_ctx;
456                 rec= &(s->s3->rrec);
457                 if (s->enc_read_ctx == NULL)
458                         enc=NULL;
459                 else
460                         enc=EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
461                 }
462
463 #ifdef KSSL_DEBUG
464         printf("tls1_enc(%d)\n", send);
465 #endif    /* KSSL_DEBUG */
466
467         if ((s->session == NULL) || (ds == NULL) ||
468                 (enc == NULL))
469                 {
470                 memmove(rec->data,rec->input,rec->length);
471                 rec->input=rec->data;
472                 }
473         else
474                 {
475                 l=rec->length;
476                 bs=EVP_CIPHER_block_size(ds->cipher);
477
478                 if ((bs != 1) && send)
479                         {
480                         i=bs-((int)l%bs);
481
482                         /* Add weird padding of upto 256 bytes */
483
484                         /* we need to add 'i' padding bytes of value j */
485                         j=i-1;
486                         if (s->options & SSL_OP_TLS_BLOCK_PADDING_BUG)
487                                 {
488                                 if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
489                                         j++;
490                                 }
491                         for (k=(int)l; k<(int)(l+i); k++)
492                                 rec->input[k]=j;
493                         l+=i;
494                         rec->length+=i;
495                         }
496
497 #ifdef KSSL_DEBUG
498                 {
499                 unsigned long ui;
500                 printf("EVP_Cipher(ds=%p,rec->data=%p,rec->input=%p,l=%ld) ==>\n",
501                         ds,rec->data,rec->input,l);
502                 printf("\tEVP_CIPHER_CTX: %d buf_len, %d key_len [%d %d], %d iv_len\n",
503                         ds->buf_len, ds->cipher->key_len,
504                         DES_KEY_SZ, DES_SCHEDULE_SZ,
505                         ds->cipher->iv_len);
506                 printf("\t\tIV: ");
507                 for (i=0; i<ds->cipher->iv_len; i++) printf("%02X", ds->iv[i]);
508                 printf("\n");
509                 printf("\trec->input=");
510                 for (ui=0; ui<l; ui++) printf(" %02x", rec->input[ui]);
511                 printf("\n");
512                 }
513 #endif  /* KSSL_DEBUG */
514
515                 if (!send)
516                         {
517                         if (l == 0 || l%bs != 0)
518                                 {
519                                 SSLerr(SSL_F_TLS1_ENC,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
520                                 ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_DECRYPTION_FAILED);
521                                 return 0;
522                                 }
523                         }
524                 
525                 EVP_Cipher(ds,rec->data,rec->input,l);
526
527 #ifdef KSSL_DEBUG
528                 {
529                 unsigned long i;
530                 printf("\trec->data=");
531                 for (i=0; i<l; i++)
532                         printf(" %02x", rec->data[i]);  printf("\n");
533                 }
534 #endif  /* KSSL_DEBUG */
535
536                 if ((bs != 1) && !send)
537                         {
538                         ii=i=rec->data[l-1]; /* padding_length */
539                         i++;
540                         if (s->options&SSL_OP_TLS_BLOCK_PADDING_BUG)
541                                 {
542                                 /* First packet is even in size, so check */
543                                 if ((memcmp(s->s3->read_sequence,
544                                         "\0\0\0\0\0\0\0\0",8) == 0) && !(ii & 1))
545                                         s->s3->flags|=TLS1_FLAGS_TLS_PADDING_BUG;
546                                 if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
547                                         i--;
548                                 }
549                         /* TLS 1.0 does not bound the number of padding bytes by the block size.
550                          * All of them must have value 'padding_length'. */
551                         if (i > (int)rec->length)
552                                 {
553                                 /* Incorrect padding. SSLerr() and ssl3_alert are done
554                                  * by caller: we don't want to reveal whether this is
555                                  * a decryption error or a MAC verification failure
556                                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
557                                 return -1;
558                                 }
559                         for (j=(int)(l-i); j<(int)l; j++)
560                                 {
561                                 if (rec->data[j] != ii)
562                                         {
563                                         /* Incorrect padding */
564                                         return -1;
565                                         }
566                                 }
567                         rec->length-=i;
568                         }
569                 }
570         return(1);
571         }
572
573 int tls1_cert_verify_mac(SSL *s, EVP_MD_CTX *in_ctx, unsigned char *out)
574         {
575         unsigned int ret;
576         EVP_MD_CTX ctx;
577
578         EVP_MD_CTX_init(&ctx);
579         EVP_MD_CTX_copy_ex(&ctx,in_ctx);
580         EVP_DigestFinal_ex(&ctx,out,&ret);
581         EVP_MD_CTX_cleanup(&ctx);
582         return((int)ret);
583         }
584
585 int tls1_final_finish_mac(SSL *s, EVP_MD_CTX *in1_ctx, EVP_MD_CTX *in2_ctx,
586              const char *str, int slen, unsigned char *out)
587         {
588         unsigned int i;
589         EVP_MD_CTX ctx;
590         unsigned char buf[TLS_MD_MAX_CONST_SIZE+MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
591         unsigned char *q,buf2[12];
592
593         q=buf;
594         memcpy(q,str,slen);
595         q+=slen;
596
597         EVP_MD_CTX_init(&ctx);
598         EVP_MD_CTX_copy_ex(&ctx,in1_ctx);
599         EVP_DigestFinal_ex(&ctx,q,&i);
600         q+=i;
601         EVP_MD_CTX_copy_ex(&ctx,in2_ctx);
602         EVP_DigestFinal_ex(&ctx,q,&i);
603         q+=i;
604
605         tls1_PRF(s->ctx->md5,s->ctx->sha1,buf,(int)(q-buf),
606                 s->session->master_key,s->session->master_key_length,
607                 out,buf2,12);
608         EVP_MD_CTX_cleanup(&ctx);
609
610         return((int)12);
611         }
612
613 int tls1_mac(SSL *ssl, unsigned char *md, int send)
614         {
615         SSL3_RECORD *rec;
616         unsigned char *mac_sec,*seq;
617         const EVP_MD *hash;
618         unsigned int md_size;
619         int i;
620         HMAC_CTX hmac;
621         unsigned char buf[5]; 
622
623         if (send)
624                 {
625                 rec= &(ssl->s3->wrec);
626                 mac_sec= &(ssl->s3->write_mac_secret[0]);
627                 seq= &(ssl->s3->write_sequence[0]);
628                 hash=ssl->write_hash;
629                 }
630         else
631                 {
632                 rec= &(ssl->s3->rrec);
633                 mac_sec= &(ssl->s3->read_mac_secret[0]);
634                 seq= &(ssl->s3->read_sequence[0]);
635                 hash=ssl->read_hash;
636                 }
637
638         md_size=EVP_MD_size(hash);
639
640         buf[0]=rec->type;
641         buf[1]=TLS1_VERSION_MAJOR;
642         buf[2]=TLS1_VERSION_MINOR;
643         buf[3]=rec->length>>8;
644         buf[4]=rec->length&0xff;
645
646         /* I should fix this up TLS TLS TLS TLS TLS XXXXXXXX */
647         HMAC_CTX_init(&hmac);
648         HMAC_Init(&hmac,mac_sec,EVP_MD_size(hash),hash);
649         HMAC_Update(&hmac,seq,8);
650         HMAC_Update(&hmac,buf,5);
651         HMAC_Update(&hmac,rec->input,rec->length);
652         HMAC_Final(&hmac,md,&md_size);
653         HMAC_CTX_cleanup(&hmac);
654
655 #ifdef TLS_DEBUG
656 printf("sec=");
657 {unsigned int z; for (z=0; z<md_size; z++) printf("%02X ",mac_sec[z]); printf("\n"); }
658 printf("seq=");
659 {int z; for (z=0; z<8; z++) printf("%02X ",seq[z]); printf("\n"); }
660 printf("buf=");
661 {int z; for (z=0; z<5; z++) printf("%02X ",buf[z]); printf("\n"); }
662 printf("rec=");
663 {unsigned int z; for (z=0; z<rec->length; z++) printf("%02X ",buf[z]); printf("\n"); }
664 #endif
665
666         for (i=7; i>=0; i--)
667                 {
668                 ++seq[i];
669                 if (seq[i] != 0) break; 
670                 }
671
672 #ifdef TLS_DEBUG
673 {unsigned int z; for (z=0; z<md_size; z++) printf("%02X ",md[z]); printf("\n"); }
674 #endif
675         return(md_size);
676         }
677
678 int tls1_generate_master_secret(SSL *s, unsigned char *out, unsigned char *p,
679              int len)
680         {
681         unsigned char buf[SSL3_RANDOM_SIZE*2+TLS_MD_MASTER_SECRET_CONST_SIZE];
682         unsigned char buff[SSL_MAX_MASTER_KEY_LENGTH];
683
684 #ifdef KSSL_DEBUG
685         printf ("tls1_generate_master_secret(%p,%p, %p, %d)\n", s,out, p,len);
686 #endif  /* KSSL_DEBUG */
687
688         /* Setup the stuff to munge */
689         memcpy(buf,TLS_MD_MASTER_SECRET_CONST,
690                 TLS_MD_MASTER_SECRET_CONST_SIZE);
691         memcpy(&(buf[TLS_MD_MASTER_SECRET_CONST_SIZE]),
692                 s->s3->client_random,SSL3_RANDOM_SIZE);
693         memcpy(&(buf[SSL3_RANDOM_SIZE+TLS_MD_MASTER_SECRET_CONST_SIZE]),
694                 s->s3->server_random,SSL3_RANDOM_SIZE);
695         tls1_PRF(s->ctx->md5,s->ctx->sha1,
696                 buf,TLS_MD_MASTER_SECRET_CONST_SIZE+SSL3_RANDOM_SIZE*2,p,len,
697                 s->session->master_key,buff,SSL3_MASTER_SECRET_SIZE);
698 #ifdef KSSL_DEBUG
699         printf ("tls1_generate_master_secret() complete\n");
700 #endif  /* KSSL_DEBUG */
701         return(SSL3_MASTER_SECRET_SIZE);
702         }
703
704 int tls1_alert_code(int code)
705         {
706         switch (code)
707                 {
708         case SSL_AD_CLOSE_NOTIFY:       return(SSL3_AD_CLOSE_NOTIFY);
709         case SSL_AD_UNEXPECTED_MESSAGE: return(SSL3_AD_UNEXPECTED_MESSAGE);
710         case SSL_AD_BAD_RECORD_MAC:     return(SSL3_AD_BAD_RECORD_MAC);
711         case SSL_AD_DECRYPTION_FAILED:  return(TLS1_AD_DECRYPTION_FAILED);
712         case SSL_AD_RECORD_OVERFLOW:    return(TLS1_AD_RECORD_OVERFLOW);
713         case SSL_AD_DECOMPRESSION_FAILURE:return(SSL3_AD_DECOMPRESSION_FAILURE);
714         case SSL_AD_HANDSHAKE_FAILURE:  return(SSL3_AD_HANDSHAKE_FAILURE);
715         case SSL_AD_NO_CERTIFICATE:     return(-1);
716         case SSL_AD_BAD_CERTIFICATE:    return(SSL3_AD_BAD_CERTIFICATE);
717         case SSL_AD_UNSUPPORTED_CERTIFICATE:return(SSL3_AD_UNSUPPORTED_CERTIFICATE);
718         case SSL_AD_CERTIFICATE_REVOKED:return(SSL3_AD_CERTIFICATE_REVOKED);
719         case SSL_AD_CERTIFICATE_EXPIRED:return(SSL3_AD_CERTIFICATE_EXPIRED);
720         case SSL_AD_CERTIFICATE_UNKNOWN:return(SSL3_AD_CERTIFICATE_UNKNOWN);
721         case SSL_AD_ILLEGAL_PARAMETER:  return(SSL3_AD_ILLEGAL_PARAMETER);
722         case SSL_AD_UNKNOWN_CA:         return(TLS1_AD_UNKNOWN_CA);
723         case SSL_AD_ACCESS_DENIED:      return(TLS1_AD_ACCESS_DENIED);
724         case SSL_AD_DECODE_ERROR:       return(TLS1_AD_DECODE_ERROR);
725         case SSL_AD_DECRYPT_ERROR:      return(TLS1_AD_DECRYPT_ERROR);
726         case SSL_AD_EXPORT_RESTRICTION: return(TLS1_AD_EXPORT_RESTRICTION);
727         case SSL_AD_PROTOCOL_VERSION:   return(TLS1_AD_PROTOCOL_VERSION);
728         case SSL_AD_INSUFFICIENT_SECURITY:return(TLS1_AD_INSUFFICIENT_SECURITY);
729         case SSL_AD_INTERNAL_ERROR:     return(TLS1_AD_INTERNAL_ERROR);
730         case SSL_AD_USER_CANCELLED:     return(TLS1_AD_USER_CANCELLED);
731         case SSL_AD_NO_RENEGOTIATION:   return(TLS1_AD_NO_RENEGOTIATION);
732         default:                        return(-1);
733                 }
734         }
735