Set TLS padding extension value.
[openssl.git] / ssl / s2_pkt.c
1 /* ssl/s2_pkt.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) 1998-2001 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 "ssl_locl.h"
113 #ifndef OPENSSL_NO_SSL2
114 #include <stdio.h>
115 #include <errno.h>
116 #define USE_SOCKETS
117
118 static int read_n(SSL *s,unsigned int n,unsigned int max,unsigned int extend);
119 static int n_do_ssl_write(SSL *s, const unsigned char *buf, unsigned int len);
120 static int write_pending(SSL *s, const unsigned char *buf, unsigned int len);
121 static int ssl_mt_error(int n);
122
123
124 /* SSL 2.0 imlementation for SSL_read/SSL_peek -
125  * This routine will return 0 to len bytes, decrypted etc if required.
126  */
127 static int ssl2_read_internal(SSL *s, void *buf, int len, int peek)
128         {
129         int n;
130         unsigned char mac[MAX_MAC_SIZE];
131         unsigned char *p;
132         int i;
133         int mac_size;
134
135  ssl2_read_again:
136         if (SSL_in_init(s) && !s->in_handshake)
137                 {
138                 n=s->handshake_func(s);
139                 if (n < 0) return(n);
140                 if (n == 0)
141                         {
142                         SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_SSL_HANDSHAKE_FAILURE);
143                         return(-1);
144                         }
145                 }
146
147         clear_sys_error();
148         s->rwstate=SSL_NOTHING;
149         if (len <= 0) return(len);
150
151         if (s->s2->ract_data_length != 0) /* read from buffer */
152                 {
153                 if (len > s->s2->ract_data_length)
154                         n=s->s2->ract_data_length;
155                 else
156                         n=len;
157
158                 memcpy(buf,s->s2->ract_data,(unsigned int)n);
159                 if (!peek)
160                         {
161                         s->s2->ract_data_length-=n;
162                         s->s2->ract_data+=n;
163                         if (s->s2->ract_data_length == 0)
164                                 s->rstate=SSL_ST_READ_HEADER;
165                         }
166
167                 return(n);
168                 }
169
170         /* s->s2->ract_data_length == 0
171          * 
172          * Fill the buffer, then goto ssl2_read_again.
173          */
174
175         if (s->rstate == SSL_ST_READ_HEADER)
176                 {
177                 if (s->first_packet)
178                         {
179                         n=read_n(s,5,SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER+2,0);
180                         if (n <= 0) return(n); /* error or non-blocking */
181                         s->first_packet=0;
182                         p=s->packet;
183                         if (!((p[0] & 0x80) && (
184                                 (p[2] == SSL2_MT_CLIENT_HELLO) ||
185                                 (p[2] == SSL2_MT_SERVER_HELLO))))
186                                 {
187                                 SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_NON_SSLV2_INITIAL_PACKET);
188                                 return(-1);
189                                 }
190                         }
191                 else
192                         {
193                         n=read_n(s,2,SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER+2,0);
194                         if (n <= 0) return(n); /* error or non-blocking */
195                         }
196                 /* part read stuff */
197
198                 s->rstate=SSL_ST_READ_BODY;
199                 p=s->packet;
200                 /* Do header */
201                 /*s->s2->padding=0;*/
202                 s->s2->escape=0;
203                 s->s2->rlength=(((unsigned int)p[0])<<8)|((unsigned int)p[1]);
204                 if ((p[0] & TWO_BYTE_BIT))              /* Two byte header? */
205                         {
206                         s->s2->three_byte_header=0;
207                         s->s2->rlength&=TWO_BYTE_MASK;  
208                         }
209                 else
210                         {
211                         s->s2->three_byte_header=1;
212                         s->s2->rlength&=THREE_BYTE_MASK;
213
214                         /* security >s2->escape */
215                         s->s2->escape=((p[0] & SEC_ESC_BIT))?1:0;
216                         }
217                 }
218
219         if (s->rstate == SSL_ST_READ_BODY)
220                 {
221                 n=s->s2->rlength+2+s->s2->three_byte_header;
222                 if (n > (int)s->packet_length)
223                         {
224                         n-=s->packet_length;
225                         i=read_n(s,(unsigned int)n,(unsigned int)n,1);
226                         if (i <= 0) return(i); /* ERROR */
227                         }
228
229                 p= &(s->packet[2]);
230                 s->rstate=SSL_ST_READ_HEADER;
231                 if (s->s2->three_byte_header)
232                         s->s2->padding= *(p++);
233                 else    s->s2->padding=0;
234
235                 /* Data portion */
236                 if (s->s2->clear_text)
237                         {
238                         mac_size = 0;
239                         s->s2->mac_data=p;
240                         s->s2->ract_data=p;
241                         if (s->s2->padding)
242                                 {
243                                 SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_ILLEGAL_PADDING);
244                                 return(-1);
245                                 }
246                         }
247                 else
248                         {
249                         mac_size=EVP_MD_CTX_size(s->read_hash);
250                         if (mac_size < 0)
251                                 return -1;
252                         OPENSSL_assert(mac_size <= MAX_MAC_SIZE);
253                         s->s2->mac_data=p;
254                         s->s2->ract_data= &p[mac_size];
255                         if (s->s2->padding + mac_size > s->s2->rlength)
256                                 {
257                                 SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_ILLEGAL_PADDING);
258                                 return(-1);
259                                 }
260                         }
261
262                 s->s2->ract_data_length=s->s2->rlength;
263                 /* added a check for length > max_size in case
264                  * encryption was not turned on yet due to an error */
265                 if ((!s->s2->clear_text) &&
266                         (s->s2->rlength >= (unsigned int)mac_size))
267                         {
268                         ssl2_enc(s,0);
269                         s->s2->ract_data_length-=mac_size;
270                         ssl2_mac(s,mac,0);
271                         s->s2->ract_data_length-=s->s2->padding;
272                         if (    (CRYPTO_memcmp(mac,s->s2->mac_data,mac_size) != 0) ||
273                                 (s->s2->rlength%EVP_CIPHER_CTX_block_size(s->enc_read_ctx) != 0))
274                                 {
275                                 SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_BAD_MAC_DECODE);
276                                 return(-1);
277                                 }
278                         }
279                 INC32(s->s2->read_sequence); /* expect next number */
280                 /* s->s2->ract_data is now available for processing */
281
282                 /* Possibly the packet that we just read had 0 actual data bytes.
283                  * (SSLeay/OpenSSL itself never sends such packets; see ssl2_write.)
284                  * In this case, returning 0 would be interpreted by the caller
285                  * as indicating EOF, so it's not a good idea.  Instead, we just
286                  * continue reading; thus ssl2_read_internal may have to process
287                  * multiple packets before it can return.
288                  *
289                  * [Note that using select() for blocking sockets *never* guarantees
290                  * that the next SSL_read will not block -- the available
291                  * data may contain incomplete packets, and except for SSL 2,
292                  * renegotiation can confuse things even more.] */
293
294                 goto ssl2_read_again; /* This should really be
295                                        * "return ssl2_read(s,buf,len)",
296                                        * but that would allow for
297                                        * denial-of-service attacks if a
298                                        * C compiler is used that does not
299                                        * recognize end-recursion. */
300                 }
301         else
302                 {
303                 SSLerr(SSL_F_SSL2_READ_INTERNAL,SSL_R_BAD_STATE);
304                         return(-1);
305                 }
306         }
307
308 int ssl2_read(SSL *s, void *buf, int len)
309         {
310         return ssl2_read_internal(s, buf, len, 0);
311         }
312
313 int ssl2_peek(SSL *s, void *buf, int len)
314         {
315         return ssl2_read_internal(s, buf, len, 1);
316         }
317
318 static int read_n(SSL *s, unsigned int n, unsigned int max,
319              unsigned int extend)
320         {
321         int i,off,newb;
322
323         /* if there is stuff still in the buffer from a previous read,
324          * and there is more than we want, take some. */
325         if (s->s2->rbuf_left >= (int)n)
326                 {
327                 if (extend)
328                         s->packet_length+=n;
329                 else
330                         {
331                         s->packet= &(s->s2->rbuf[s->s2->rbuf_offs]);
332                         s->packet_length=n;
333                         }
334                 s->s2->rbuf_left-=n;
335                 s->s2->rbuf_offs+=n;
336                 return(n);
337                 }
338
339         if (!s->read_ahead) max=n;
340         if (max > (unsigned int)(SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER+2))
341                 max=SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER+2;
342         
343
344         /* Else we want more than we have.
345          * First, if there is some left or we want to extend */
346         off=0;
347         if ((s->s2->rbuf_left != 0) || ((s->packet_length != 0) && extend))
348                 {
349                 newb=s->s2->rbuf_left;
350                 if (extend)
351                         {
352                         off=s->packet_length;
353                         if (s->packet != s->s2->rbuf)
354                                 memcpy(s->s2->rbuf,s->packet,
355                                         (unsigned int)newb+off);
356                         }
357                 else if (s->s2->rbuf_offs != 0)
358                         {
359                         memcpy(s->s2->rbuf,&(s->s2->rbuf[s->s2->rbuf_offs]),
360                                 (unsigned int)newb);
361                         s->s2->rbuf_offs=0;
362                         }
363                 s->s2->rbuf_left=0;
364                 }
365         else
366                 newb=0;
367
368         /* off is the offset to start writing too.
369          * r->s2->rbuf_offs is the 'unread data', now 0. 
370          * newb is the number of new bytes so far
371          */
372         s->packet=s->s2->rbuf;
373         while (newb < (int)n)
374                 {
375                 clear_sys_error();
376                 if (s->rbio != NULL)
377                         {
378                         s->rwstate=SSL_READING;
379                         i=BIO_read(s->rbio,(char *)&(s->s2->rbuf[off+newb]),
380                                 max-newb);
381                         }
382                 else
383                         {
384                         SSLerr(SSL_F_READ_N,SSL_R_READ_BIO_NOT_SET);
385                         i= -1;
386                         }
387 #ifdef PKT_DEBUG
388                 if (s->debug & 0x01) sleep(1);
389 #endif
390                 if (i <= 0)
391                         {
392                         s->s2->rbuf_left+=newb;
393                         return(i);
394                         }
395                 newb+=i;
396                 }
397
398         /* record unread data */
399         if (newb > (int)n)
400                 {
401                 s->s2->rbuf_offs=n+off;
402                 s->s2->rbuf_left=newb-n;
403                 }
404         else
405                 {
406                 s->s2->rbuf_offs=0;
407                 s->s2->rbuf_left=0;
408                 }
409         if (extend)
410                 s->packet_length+=n;
411         else
412                 s->packet_length=n;
413         s->rwstate=SSL_NOTHING;
414         return(n);
415         }
416
417 int ssl2_write(SSL *s, const void *_buf, int len)
418         {
419         const unsigned char *buf=_buf;
420         unsigned int n,tot;
421         int i;
422
423         if (SSL_in_init(s) && !s->in_handshake)
424                 {
425                 i=s->handshake_func(s);
426                 if (i < 0) return(i);
427                 if (i == 0)
428                         {
429                         SSLerr(SSL_F_SSL2_WRITE,SSL_R_SSL_HANDSHAKE_FAILURE);
430                         return(-1);
431                         }
432                 }
433
434         if (s->error)
435                 {
436                 ssl2_write_error(s);
437                 if (s->error)
438                         return(-1);
439                 }
440
441         clear_sys_error();
442         s->rwstate=SSL_NOTHING;
443         if (len <= 0) return(len);
444
445         tot=s->s2->wnum;
446         s->s2->wnum=0;
447
448         n=(len-tot);
449         for (;;)
450                 {
451                 i=n_do_ssl_write(s,&(buf[tot]),n);
452                 if (i <= 0)
453                         {
454                         s->s2->wnum=tot;
455                         return(i);
456                         }
457                 if ((i == (int)n) ||
458                         (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))
459                         {
460                         return(tot+i);
461                         }
462                 
463                 n-=i;
464                 tot+=i;
465                 }
466         }
467
468 static int write_pending(SSL *s, const unsigned char *buf, unsigned int len)
469         {
470         int i;
471
472         /* s->s2->wpend_len != 0 MUST be true. */
473
474         /* check that they have given us the same buffer to
475          * write */
476         if ((s->s2->wpend_tot > (int)len) ||
477                 ((s->s2->wpend_buf != buf) &&
478                  !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)))
479                 {
480                 SSLerr(SSL_F_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
481                 return(-1);
482                 }
483
484         for (;;)
485                 {
486                 clear_sys_error();
487                 if (s->wbio != NULL)
488                         {
489                         s->rwstate=SSL_WRITING;
490                         i=BIO_write(s->wbio,
491                                 (char *)&(s->s2->write_ptr[s->s2->wpend_off]),
492                                 (unsigned int)s->s2->wpend_len);
493                         }
494                 else
495                         {
496                         SSLerr(SSL_F_WRITE_PENDING,SSL_R_WRITE_BIO_NOT_SET);
497                         i= -1;
498                         }
499 #ifdef PKT_DEBUG
500                 if (s->debug & 0x01) sleep(1);
501 #endif
502                 if (i == s->s2->wpend_len)
503                         {
504                         s->s2->wpend_len=0;
505                         s->rwstate=SSL_NOTHING;
506                         return(s->s2->wpend_ret);
507                         }
508                 else if (i <= 0)
509                         return(i);
510                 s->s2->wpend_off+=i;
511                 s->s2->wpend_len-=i;
512                 }
513         }
514
515 static int n_do_ssl_write(SSL *s, const unsigned char *buf, unsigned int len)
516         {
517         unsigned int j,k,olen,p,bs;
518         int mac_size;
519         register unsigned char *pp;
520
521         olen=len;
522
523         /* first check if there is data from an encryption waiting to
524          * be sent - it must be sent because the other end is waiting.
525          * This will happen with non-blocking IO.  We print it and then
526          * return.
527          */
528         if (s->s2->wpend_len != 0) return(write_pending(s,buf,len));
529
530         /* set mac_size to mac size */
531         if (s->s2->clear_text)
532                 mac_size=0;
533         else
534                 {
535                 mac_size=EVP_MD_CTX_size(s->write_hash);
536                 if (mac_size < 0)
537                         return -1;
538                 }
539
540         /* lets set the pad p */
541         if (s->s2->clear_text)
542                 {
543                 if (len > SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER)
544                         len=SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER;
545                 p=0;
546                 s->s2->three_byte_header=0;
547                 /* len=len; */
548                 }
549         else
550                 {
551                 bs=EVP_CIPHER_CTX_block_size(s->enc_read_ctx);
552                 j=len+mac_size;
553                 /* Two-byte headers allow for a larger record length than
554                  * three-byte headers, but we can't use them if we need
555                  * padding or if we have to set the escape bit. */
556                 if ((j > SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER) &&
557                         (!s->s2->escape))
558                         {
559                         if (j > SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER)
560                                 j=SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER;
561                         /* set k to the max number of bytes with 2
562                          * byte header */
563                         k=j-(j%bs);
564                         /* how many data bytes? */
565                         len=k-mac_size; 
566                         s->s2->three_byte_header=0;
567                         p=0;
568                         }
569                 else if ((bs <= 1) && (!s->s2->escape))
570                         {
571                         /* j <= SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER, thus
572                          * j < SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER */
573                         s->s2->three_byte_header=0;
574                         p=0;
575                         }
576                 else /* we may have to use a 3 byte header */
577                         {
578                         /* If s->s2->escape is not set, then
579                          * j <= SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER, and thus
580                          * j < SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER. */
581                         p=(j%bs);
582                         p=(p == 0)?0:(bs-p);
583                         if (s->s2->escape)
584                                 {
585                                 s->s2->three_byte_header=1;
586                                 if (j > SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER)
587                                         j=SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER;
588                                 }
589                         else
590                                 s->s2->three_byte_header=(p == 0)?0:1;
591                         }
592                 }
593
594         /* Now
595          *      j <= SSL2_MAX_RECORD_LENGTH_2_BYTE_HEADER
596          * holds, and if s->s2->three_byte_header is set, then even
597          *      j <= SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER.
598          */
599
600         /* mac_size is the number of MAC bytes
601          * len is the number of data bytes we are going to send
602          * p is the number of padding bytes
603          * (if it is a two-byte header, then p == 0) */
604
605         s->s2->wlength=len;
606         s->s2->padding=p;
607         s->s2->mac_data= &(s->s2->wbuf[3]);
608         s->s2->wact_data= &(s->s2->wbuf[3+mac_size]);
609         /* we copy the data into s->s2->wbuf */
610         memcpy(s->s2->wact_data,buf,len);
611         if (p)
612                 memset(&(s->s2->wact_data[len]),0,p); /* arbitrary padding */
613
614         if (!s->s2->clear_text)
615                 {
616                 s->s2->wact_data_length=len+p;
617                 ssl2_mac(s,s->s2->mac_data,1);
618                 s->s2->wlength+=p+mac_size;
619                 ssl2_enc(s,1);
620                 }
621
622         /* package up the header */
623         s->s2->wpend_len=s->s2->wlength;
624         if (s->s2->three_byte_header) /* 3 byte header */
625                 {
626                 pp=s->s2->mac_data;
627                 pp-=3;
628                 pp[0]=(s->s2->wlength>>8)&(THREE_BYTE_MASK>>8);
629                 if (s->s2->escape) pp[0]|=SEC_ESC_BIT;
630                 pp[1]=s->s2->wlength&0xff;
631                 pp[2]=s->s2->padding;
632                 s->s2->wpend_len+=3;
633                 }
634         else
635                 {
636                 pp=s->s2->mac_data;
637                 pp-=2;
638                 pp[0]=((s->s2->wlength>>8)&(TWO_BYTE_MASK>>8))|TWO_BYTE_BIT;
639                 pp[1]=s->s2->wlength&0xff;
640                 s->s2->wpend_len+=2;
641                 }
642         s->s2->write_ptr=pp;
643         
644         INC32(s->s2->write_sequence); /* expect next number */
645
646         /* lets try to actually write the data */
647         s->s2->wpend_tot=olen;
648         s->s2->wpend_buf=buf;
649
650         s->s2->wpend_ret=len;
651
652         s->s2->wpend_off=0;
653         return(write_pending(s,buf,olen));
654         }
655
656 int ssl2_part_read(SSL *s, unsigned long f, int i)
657         {
658         unsigned char *p;
659         int j;
660
661         if (i < 0)
662                 {
663                 /* ssl2_return_error(s); */
664                 /* for non-blocking io,
665                  * this is not necessarily fatal */
666                 return(i);
667                 }
668         else
669                 {
670                 s->init_num+=i;
671
672                 /* Check for error.  While there are recoverable errors,
673                  * this function is not called when those must be expected;
674                  * any error detected here is fatal. */
675                 if (s->init_num >= 3)
676                         {
677                         p=(unsigned char *)s->init_buf->data;
678                         if (p[0] == SSL2_MT_ERROR)
679                                 {
680                                 j=(p[1]<<8)|p[2];
681                                 SSLerr((int)f,ssl_mt_error(j));
682                                 s->init_num -= 3;
683                                 if (s->init_num > 0)
684                                         memmove(p, p+3, s->init_num);
685                                 }
686                         }
687
688                 /* If it's not an error message, we have some error anyway --
689                  * the message was shorter than expected.  This too is treated
690                  * as fatal (at least if SSL_get_error is asked for its opinion). */
691                 return(0);
692                 }
693         }
694
695 int ssl2_do_write(SSL *s)
696         {
697         int ret;
698
699         ret=ssl2_write(s,&s->init_buf->data[s->init_off],s->init_num);
700         if (ret == s->init_num)
701                 {
702                 if (s->msg_callback)
703                         s->msg_callback(1, s->version, 0, s->init_buf->data, (size_t)(s->init_off + s->init_num), s, s->msg_callback_arg);
704                 return(1);
705                 }
706         if (ret < 0)
707                 return(-1);
708         s->init_off+=ret;
709         s->init_num-=ret;
710         return(0);
711         }
712
713 static int ssl_mt_error(int n)
714         {
715         int ret;
716
717         switch (n)
718                 {
719         case SSL2_PE_NO_CIPHER:
720                 ret=SSL_R_PEER_ERROR_NO_CIPHER;
721                 break;
722         case SSL2_PE_NO_CERTIFICATE:
723                 ret=SSL_R_PEER_ERROR_NO_CERTIFICATE;
724                 break;
725         case SSL2_PE_BAD_CERTIFICATE:
726                 ret=SSL_R_PEER_ERROR_CERTIFICATE;
727                 break;
728         case SSL2_PE_UNSUPPORTED_CERTIFICATE_TYPE:
729                 ret=SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE;
730                 break;
731         default:
732                 ret=SSL_R_UNKNOWN_REMOTE_ERROR_TYPE;
733                 break;
734                 }
735         return(ret);
736         }
737 #else /* !OPENSSL_NO_SSL2 */
738
739 # if PEDANTIC
740 static void *dummy=&dummy;
741 # endif
742
743 #endif