a1a701458527fd5b3da13fc357875580df7342e4
[oweals/openssl.git] / ssl / s3_pkt.c
1 /* ssl/s3_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) 1998-1999 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 <errno.h>
114 #define USE_SOCKETS
115 #include <openssl/evp.h>
116 #include <openssl/buffer.h>
117 #include "ssl_locl.h"
118
119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
120                          unsigned int len);
121 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
122                               unsigned int len);
123 static int ssl3_get_record(SSL *s);
124 static int do_compress(SSL *ssl);
125 static int do_uncompress(SSL *ssl);
126 static int do_change_cipher_spec(SSL *ssl);
127
128 static int ssl3_read_n(SSL *s, int n, int max, int extend)
129         {
130         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
131          * packet by another n bytes.
132          * The packet will be in the sub-array of s->s3->rbuf.buf specified
133          * by s->packet and s->packet_length.
134          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
135          * [plus s->packet_length bytes if extend == 1].)
136          */
137         int i,off,newb;
138
139         if (!extend)
140                 {
141                 /* start with empty packet ... */
142                 if (s->s3->rbuf.left == 0)
143                         s->s3->rbuf.offset = 0;
144                 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
145                 s->packet_length = 0;
146                 /* ... now we can act as if 'extend' was set */
147                 }
148
149         /* if there is enough in the buffer from a previous read, take some */
150         if (s->s3->rbuf.left >= (int)n)
151                 {
152                 s->packet_length+=n;
153                 s->s3->rbuf.left-=n;
154                 s->s3->rbuf.offset+=n;
155                 return(n);
156                 }
157
158         /* else we need to read more data */
159         if (!s->read_ahead)
160                 max=n;
161
162         {
163                 /* avoid buffer overflow */
164                 int max_max = SSL3_RT_MAX_PACKET_SIZE - s->packet_length;
165                 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
166                         max_max += SSL3_RT_MAX_EXTRA;
167                 if (max > max_max)
168                         max = max_max;
169         }
170         if (n > max) /* does not happen */
171                 {
172                 SSLerr(SSL_F_SSL3_READ_N,SSL_R_INTERNAL_ERROR);
173                 return -1;
174                 }
175
176         off = s->packet_length;
177         newb = s->s3->rbuf.left;
178         /* Move any available bytes to front of buffer:
179          * 'off' bytes already pointed to by 'packet',
180          * 'newb' extra ones at the end */
181         if (s->packet != s->s3->rbuf.buf)
182                 {
183                 /*  off > 0 */
184                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
185                 s->packet = s->s3->rbuf.buf;
186                 }
187         
188         while (newb < n)
189                 {
190                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
191                  * to read in more until we have off+n (up to off+max if possible) */
192
193                 clear_sys_error();
194                 if (s->rbio != NULL)
195                         {
196                         s->rwstate=SSL_READING;
197                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
198                         }
199                 else
200                         {
201                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
202                         i = -1;
203                         }
204
205                 if (i <= 0)
206                         {
207                         s->s3->rbuf.left = newb;
208                         return(i);
209                         }
210                 newb+=i;
211                 }
212
213         /* done reading, now the book-keeping */
214         s->s3->rbuf.offset = off + n;
215         s->s3->rbuf.left = newb - n;
216         s->packet_length += n;
217         s->rwstate=SSL_NOTHING;
218         return(n);
219         }
220
221 /* Call this to get a new input record.
222  * It will return <= 0 if more data is needed, normally due to an error
223  * or non-blocking IO.
224  * When it finishes, one packet has been decoded and can be found in
225  * ssl->s3->rrec.type    - is the type of record
226  * ssl->s3->rrec.data,   - data
227  * ssl->s3->rrec.length, - number of bytes
228  */
229 static int ssl3_get_record(SSL *s)
230         {
231         int ssl_major,ssl_minor,al;
232         int n,i,ret= -1;
233         SSL3_BUFFER *rb;
234         SSL3_RECORD *rr;
235         SSL_SESSION *sess;
236         unsigned char *p;
237         unsigned char md[EVP_MAX_MD_SIZE];
238         short version;
239         unsigned int mac_size;
240         int clear=0,extra;
241
242         rr= &(s->s3->rrec);
243         rb= &(s->s3->rbuf);
244         sess=s->session;
245
246         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
247                 extra=SSL3_RT_MAX_EXTRA;
248         else
249                 extra=0;
250
251 again:
252         /* check if we have the header */
253         if (    (s->rstate != SSL_ST_READ_BODY) ||
254                 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 
255                 {
256                 n=ssl3_read_n(s,SSL3_RT_HEADER_LENGTH,
257                         SSL3_RT_MAX_PACKET_SIZE,0);
258                 if (n <= 0) return(n); /* error or non-blocking */
259                 s->rstate=SSL_ST_READ_BODY;
260
261                 p=s->packet;
262
263                 /* Pull apart the header into the SSL3_RECORD */
264                 rr->type= *(p++);
265                 ssl_major= *(p++);
266                 ssl_minor= *(p++);
267                 version=(ssl_major<<8)|ssl_minor;
268                 n2s(p,rr->length);
269
270                 /* Lets check version */
271                 if (s->first_packet)
272                         {
273                         s->first_packet=0;
274                         }
275                 else
276                         {
277                         if (version != s->version)
278                                 {
279                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
280                                 /* Send back error using their
281                                  * version number :-) */
282                                 s->version=version;
283                                 al=SSL_AD_PROTOCOL_VERSION;
284                                 goto f_err;
285                                 }
286                         }
287
288                 if ((version>>8) != SSL3_VERSION_MAJOR)
289                         {
290                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
291                         goto err;
292                         }
293
294                 if (rr->length > 
295                         (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
296                         {
297                         al=SSL_AD_RECORD_OVERFLOW;
298                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
299                         goto f_err;
300                         }
301
302                 /* now s->rstate == SSL_ST_READ_BODY */
303                 }
304
305         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
306
307         if (rr->length > (s->packet_length-SSL3_RT_HEADER_LENGTH))
308                 {
309                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
310                 i=rr->length;
311                 n=ssl3_read_n(s,i,i,1);
312                 if (n <= 0) return(n); /* error or non-blocking io */
313                 /* now n == rr->length,
314                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
315                 }
316
317         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
318
319         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
320          * and we have that many bytes in s->packet
321          */
322         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
323
324         /* ok, we can now read from 's->packet' data into 'rr'
325          * rr->input points at rr->length bytes, which
326          * need to be copied into rr->data by either
327          * the decryption or by the decompression
328          * When the data is 'copied' into the rr->data buffer,
329          * rr->input will be pointed at the new buffer */ 
330
331         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
332          * rr->length bytes of encrypted compressed stuff. */
333
334         /* check is not needed I belive */
335         if (rr->length > (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
336                 {
337                 al=SSL_AD_RECORD_OVERFLOW;
338                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
339                 goto f_err;
340                 }
341
342         /* decrypt in place in 'rr->input' */
343         rr->data=rr->input;
344
345         if (!s->method->ssl3_enc->enc(s,0))
346                 {
347                 al=SSL_AD_DECRYPT_ERROR;
348                 goto f_err;
349                 }
350 #ifdef TLS_DEBUG
351 printf("dec %d\n",rr->length);
352 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
353 printf("\n");
354 #endif
355         /* r->length is now the compressed data plus mac */
356         if (    (sess == NULL) ||
357                 (s->enc_read_ctx == NULL) ||
358                 (s->read_hash == NULL))
359                 clear=1;
360
361         if (!clear)
362                 {
363                 mac_size=EVP_MD_size(s->read_hash);
364
365                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
366                         {
367                         al=SSL_AD_RECORD_OVERFLOW;
368                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
369                         goto f_err;
370                         }
371                 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
372                 if (rr->length < mac_size)
373                         {
374                         al=SSL_AD_DECODE_ERROR;
375                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
376                         goto f_err;
377                         }
378                 rr->length-=mac_size;
379                 i=s->method->ssl3_enc->mac(s,md,0);
380                 if (memcmp(md,&(rr->data[rr->length]),mac_size) != 0)
381                         {
382                         al=SSL_AD_BAD_RECORD_MAC;
383                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_MAC_DECODE);
384                         ret= -1;
385                         goto f_err;
386                         }
387                 }
388
389         /* r->length is now just compressed */
390         if (s->expand != NULL)
391                 {
392                 if (rr->length > 
393                         (unsigned int)SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
394                         {
395                         al=SSL_AD_RECORD_OVERFLOW;
396                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
397                         goto f_err;
398                         }
399                 if (!do_uncompress(s))
400                         {
401                         al=SSL_AD_DECOMPRESSION_FAILURE;
402                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
403                         goto f_err;
404                         }
405                 }
406
407         if (rr->length > (unsigned int)SSL3_RT_MAX_PLAIN_LENGTH+extra)
408                 {
409                 al=SSL_AD_RECORD_OVERFLOW;
410                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
411                 goto f_err;
412                 }
413
414         rr->off=0;
415         /* So at this point the following is true
416          * ssl->s3->rrec.type   is the type of record
417          * ssl->s3->rrec.length == number of bytes in record
418          * ssl->s3->rrec.off    == offset to first valid byte
419          * ssl->s3->rrec.data   == where to take bytes from, increment
420          *                         after use :-).
421          */
422
423         /* we have pulled in a full packet so zero things */
424         s->packet_length=0;
425
426         /* just read a 0 length packet */
427         if (rr->length == 0) goto again;
428
429         return(1);
430 f_err:
431         ssl3_send_alert(s,SSL3_AL_FATAL,al);
432 err:
433         return(ret);
434         }
435
436 static int do_uncompress(SSL *ssl)
437         {
438         int i;
439         SSL3_RECORD *rr;
440
441         rr= &(ssl->s3->rrec);
442         i=COMP_expand_block(ssl->expand,rr->comp,
443                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
444         if (i < 0)
445                 return(0);
446         else
447                 rr->length=i;
448         rr->data=rr->comp;
449
450         return(1);
451         }
452
453 static int do_compress(SSL *ssl)
454         {
455         int i;
456         SSL3_RECORD *wr;
457
458         wr= &(ssl->s3->wrec);
459         i=COMP_compress_block(ssl->compress,wr->data,
460                 SSL3_RT_MAX_COMPRESSED_LENGTH,
461                 wr->input,(int)wr->length);
462         if (i < 0)
463                 return(0);
464         else
465                 wr->length=i;
466
467         wr->input=wr->data;
468         return(1);
469         }
470
471 /* Call this to write data in records of type 'type'
472  * It will return <= 0 if not all data has been sent or non-blocking IO.
473  */
474 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
475         {
476         const unsigned char *buf=buf_;
477         unsigned int tot,n,nw;
478         int i;
479
480         s->rwstate=SSL_NOTHING;
481         tot=s->s3->wnum;
482         s->s3->wnum=0;
483
484         if (SSL_in_init(s) && !s->in_handshake)
485                 {
486                 i=s->handshake_func(s);
487                 if (i < 0) return(i);
488                 if (i == 0)
489                         {
490                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
491                         return(-1);
492                         }
493                 }
494
495         n=(len-tot);
496         for (;;)
497                 {
498                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
499                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
500                 else
501                         nw=n;
502                         
503                 i=do_ssl3_write(s,type,&(buf[tot]),nw);
504                 if (i <= 0)
505                         {
506                         s->s3->wnum=tot;
507                         return(i);
508                         }
509
510                 if (type == SSL3_RT_HANDSHAKE)
511                         ssl3_finish_mac(s,&(buf[tot]),i);
512
513                 if ((i == (int)n) ||
514                         (type == SSL3_RT_APPLICATION_DATA &&
515                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
516                         {
517                         return(tot+i);
518                         }
519
520                 n-=i;
521                 tot+=i;
522                 }
523         }
524
525 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
526                          unsigned int len)
527         {
528         unsigned char *p,*plen;
529         int i,mac_size,clear=0;
530         SSL3_RECORD *wr;
531         SSL3_BUFFER *wb;
532         SSL_SESSION *sess;
533
534         /* first check is there is a SSL3_RECORD still being written
535          * out.  This will happen with non blocking IO */
536         if (s->s3->wbuf.left != 0)
537                 return(ssl3_write_pending(s,type,buf,len));
538
539         /* If we have an alert to send, lets send it */
540         if (s->s3->alert_dispatch)
541                 {
542                 i=ssl3_dispatch_alert(s);
543                 if (i <= 0)
544                         return(i);
545                 /* if it went, fall through and send more stuff */
546                 }
547
548         if (len == 0) return(len);
549         
550         wr= &(s->s3->wrec);
551         wb= &(s->s3->wbuf);
552         sess=s->session;
553
554         if (    (sess == NULL) ||
555                 (s->enc_write_ctx == NULL) ||
556                 (s->write_hash == NULL))
557                 clear=1;
558
559         if (clear)
560                 mac_size=0;
561         else
562                 mac_size=EVP_MD_size(s->write_hash);
563
564         p=wb->buf;
565
566         /* write the header */
567         *(p++)=type&0xff;
568         wr->type=type;
569
570         *(p++)=(s->version>>8);
571         *(p++)=s->version&0xff;
572         
573         /* record where we are to write out packet length */
574         plen=p; 
575         p+=2;
576         
577         /* lets setup the record stuff. */
578         wr->data=p;
579         wr->length=(int)len;
580         wr->input=(unsigned char *)buf;
581
582         /* we now 'read' from wr->input, wr->length bytes into
583          * wr->data */
584
585         /* first we compress */
586         if (s->compress != NULL)
587                 {
588                 if (!do_compress(s))
589                         {
590                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
591                         goto err;
592                         }
593                 }
594         else
595                 {
596                 memcpy(wr->data,wr->input,wr->length);
597                 wr->input=wr->data;
598                 }
599
600         /* we should still have the output to wr->data and the input
601          * from wr->input.  Length should be wr->length.
602          * wr->data still points in the wb->buf */
603
604         if (mac_size != 0)
605                 {
606                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
607                 wr->length+=mac_size;
608                 wr->input=p;
609                 wr->data=p;
610                 }
611
612         /* ssl3_enc can only have an error on read */
613         s->method->ssl3_enc->enc(s,1);
614
615         /* record length after mac and block padding */
616         s2n(wr->length,plen);
617
618         /* we should now have
619          * wr->data pointing to the encrypted data, which is
620          * wr->length long */
621         wr->type=type; /* not needed but helps for debugging */
622         wr->length+=SSL3_RT_HEADER_LENGTH;
623
624         /* Now lets setup wb */
625         wb->left=wr->length;
626         wb->offset=0;
627
628         s->s3->wpend_tot=len;
629         s->s3->wpend_buf=buf;
630         s->s3->wpend_type=type;
631         s->s3->wpend_ret=len;
632
633         /* we now just need to write the buffer */
634         return(ssl3_write_pending(s,type,buf,len));
635 err:
636         return(-1);
637         }
638
639 /* if s->s3->wbuf.left != 0, we need to call this */
640 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
641                               unsigned int len)
642         {
643         int i;
644
645 /* XXXX */
646         if ((s->s3->wpend_tot > (int)len)
647                 || ((s->s3->wpend_buf != buf) &&
648                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
649                 || (s->s3->wpend_type != type))
650                 {
651                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
652                 return(-1);
653                 }
654
655         for (;;)
656                 {
657                 clear_sys_error();
658                 if (s->wbio != NULL)
659                         {
660                         s->rwstate=SSL_WRITING;
661                         i=BIO_write(s->wbio,
662                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
663                                 (unsigned int)s->s3->wbuf.left);
664                         }
665                 else
666                         {
667                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
668                         i= -1;
669                         }
670                 if (i == s->s3->wbuf.left)
671                         {
672                         s->s3->wbuf.left=0;
673                         s->rwstate=SSL_NOTHING;
674                         return(s->s3->wpend_ret);
675                         }
676                 else if (i <= 0)
677                         return(i);
678                 s->s3->wbuf.offset+=i;
679                 s->s3->wbuf.left-=i;
680                 }
681         }
682
683 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len)
684         {
685         int al,i,j,n,ret;
686         SSL3_RECORD *rr;
687         void (*cb)()=NULL;
688         BIO *bio;
689
690         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
691                 if (!ssl3_setup_buffers(s))
692                         return(-1);
693
694         if (!s->in_handshake && SSL_in_init(s))
695                 {
696                 i=s->handshake_func(s);
697                 if (i < 0) return(i);
698                 if (i == 0)
699                         {
700                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
701                         return(-1);
702                         }
703                 }
704 start:
705         s->rwstate=SSL_NOTHING;
706
707         /* s->s3->rrec.type         - is the type of record
708          * s->s3->rrec.data,    - data
709          * s->s3->rrec.off,     - offset into 'data' for next read
710          * s->s3->rrec.length,  - number of bytes. */
711         rr= &(s->s3->rrec);
712
713         /* get new packet */
714         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
715                 {
716                 ret=ssl3_get_record(s);
717                 if (ret <= 0) return(ret);
718                 }
719
720         /* we now have a packet which can be read and processed */
721
722         if (s->s3->change_cipher_spec && (rr->type != SSL3_RT_HANDSHAKE))
723                 {
724                 al=SSL_AD_UNEXPECTED_MESSAGE;
725                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
726                 goto err;
727                 }
728
729         /* If the other end has shutdown, throw anything we read away */
730         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
731                 {
732                 rr->length=0;
733                 s->rwstate=SSL_NOTHING;
734                 return(0);
735                 }
736
737         /* Check for an incoming 'Hello Request' message from client */
738         if ((rr->type == SSL3_RT_HANDSHAKE) && (rr->length == 4) &&
739                 (rr->data[0] == SSL3_MT_HELLO_REQUEST) &&
740                 (s->session != NULL) && (s->session->cipher != NULL))
741                 {
742                 if ((rr->data[1] != 0) || (rr->data[2] != 0) ||
743                         (rr->data[3] != 0))
744                         {
745                         al=SSL_AD_DECODE_ERROR;
746                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
747                         goto err;
748                         }
749
750                 if (SSL_is_init_finished(s) &&
751                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
752                         !s->s3->renegotiate)
753                         {
754                         ssl3_renegotiate(s);
755                         if (ssl3_renegotiate_check(s))
756                                 {
757                                 n=s->handshake_func(s);
758                                 if (n < 0) return(n);
759                                 if (n == 0)
760                                         {
761                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
762                                         return(-1);
763                                         }
764                                 }
765                         }
766                 rr->length=0;
767 /* ZZZ */       goto start;
768                 }
769
770         /* if it is not the type we want, or we have shutdown and want
771          * the peer shutdown */
772         if ((rr->type != type) || (s->shutdown & SSL_SENT_SHUTDOWN))
773                 {
774                 if (rr->type == SSL3_RT_ALERT)
775                         {
776                         if ((rr->length != 2) || (rr->off != 0))
777                                 {
778                                 al=SSL_AD_DECODE_ERROR;
779                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_ALERT_RECORD);
780                                 goto f_err;
781                                 }
782
783                         i=rr->data[0];
784                         n=rr->data[1];
785
786                         /* clear from buffer */
787                         rr->length=0;
788
789                         if (s->info_callback != NULL)
790                                 cb=s->info_callback;
791                         else if (s->ctx->info_callback != NULL)
792                                 cb=s->ctx->info_callback;
793
794                         if (cb != NULL)
795                                 {
796                                 j=(i<<8)|n;
797                                 cb(s,SSL_CB_READ_ALERT,j);
798                                 }
799
800                         if (i == 1) /* warning */
801                                 {
802                                 s->s3->warn_alert=n;
803                                 if (n == SSL_AD_CLOSE_NOTIFY)
804                                         {
805                                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
806                                         return(0);
807                                         }
808                                 }
809                         else if (i == 2) /* fatal */
810                                 {
811                                 char tmp[16];
812
813                                 s->rwstate=SSL_NOTHING;
814                                 s->s3->fatal_alert=n;
815                                 SSLerr(SSL_F_SSL3_READ_BYTES,
816                                         SSL_AD_REASON_OFFSET+n);
817                                 sprintf(tmp,"%d",n);
818                                 ERR_add_error_data(2,"SSL alert number ",tmp);
819                                 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
820                                 SSL_CTX_remove_session(s->ctx,s->session);
821                                 return(0);
822                                 }
823                         else
824                                 {
825                                 al=SSL_AD_ILLEGAL_PARAMETER;
826                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
827                                 goto f_err;
828                                 }
829
830                         rr->length=0;
831                         goto start;
832                         }
833
834                 if (s->shutdown & SSL_SENT_SHUTDOWN)
835                         {
836                         s->rwstate=SSL_NOTHING;
837                         rr->length=0;
838                         return(0);
839                         }
840
841                 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
842                         {
843                         if (    (rr->length != 1) || (rr->off != 0) ||
844                                 (rr->data[0] != SSL3_MT_CCS))
845                                 {
846                                 i=SSL_AD_ILLEGAL_PARAMETER;
847                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
848                                 goto err;
849                                 }
850
851                         rr->length=0;
852                         s->s3->change_cipher_spec=1;
853                         if (!do_change_cipher_spec(s))
854                                 goto err;
855                         else
856                                 goto start;
857                         }
858
859                 /* else we have a handshake */
860                 if ((rr->type == SSL3_RT_HANDSHAKE) &&
861                         !s->in_handshake)
862                         {
863                         if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
864                                 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
865                                 {
866                                 s->state=SSL_ST_BEFORE|(s->server)
867                                                 ?SSL_ST_ACCEPT
868                                                 :SSL_ST_CONNECT;
869                                 s->new_session=1;
870                                 }
871                         n=s->handshake_func(s);
872                         if (n < 0) return(n);
873                         if (n == 0)
874                                 {
875                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
876                                 return(-1);
877                                 }
878
879                         /* In the case where we try to read application data
880                          * the first time, but we trigger an SSL handshake, we
881                          * return -1 with the retry option set.  I do this
882                          * otherwise renegotiation can cause nasty problems 
883                          * in the non-blocking world */
884
885                         s->rwstate=SSL_READING;
886                         bio=SSL_get_rbio(s);
887                         BIO_clear_retry_flags(bio);
888                         BIO_set_retry_read(bio);
889                         return(-1);
890                         }
891
892                 switch (rr->type)
893                         {
894                 default:
895 #ifndef NO_TLS
896                         /* TLS just ignores unknown message types */
897                         if (s->version == TLS1_VERSION)
898                                 {
899                                 goto start;
900                                 }
901 #endif
902                 case SSL3_RT_CHANGE_CIPHER_SPEC:
903                 case SSL3_RT_ALERT:
904                 case SSL3_RT_HANDSHAKE:
905                         al=SSL_AD_UNEXPECTED_MESSAGE;
906                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
907                         goto f_err;
908                 case SSL3_RT_APPLICATION_DATA:
909                         /* At this point, we were expecting something else,
910                          * but have application data.  What we do is set the
911                          * error, and return -1.  On the way out, if the
912                          * library was running inside ssl3_read() and it makes
913                          * sense to read application data at this point, we
914                          * will indulge it.  This will mostly happen during
915                          * session renegotiation.
916                          */
917                         if (s->s3->in_read_app_data &&
918                                 (s->s3->total_renegotiations != 0) &&
919                                 ((
920                                   (s->state & SSL_ST_CONNECT) &&
921                                   (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
922                                   (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
923                                  ) || (
924                                   (s->state & SSL_ST_ACCEPT) &&
925                                   (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
926                                   (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
927                                  )
928                                 ))
929                                 {
930                                 s->s3->in_read_app_data=0;
931                                 return(-1);
932                                 }
933                         else
934                                 {
935                                 al=SSL_AD_UNEXPECTED_MESSAGE;
936                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
937                                 goto f_err;
938                                 }
939                         }
940                 /* not reached */
941                 }
942
943         /* rr->type == type */
944
945         /* make sure that we are not getting application data when we
946          * are doing a handshake for the first time */
947         if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
948                 (s->enc_read_ctx == NULL))
949                 {
950                 al=SSL_AD_UNEXPECTED_MESSAGE;
951                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
952                 goto f_err;
953                 }
954
955         if (len <= 0) return(len);
956
957         if ((unsigned int)len > rr->length)
958                 n=rr->length;
959         else
960                 n=len;
961
962         memcpy(buf,&(rr->data[rr->off]),(unsigned int)n);
963         rr->length-=n;
964         rr->off+=n;
965         if (rr->length == 0)
966                 {
967                 s->rstate=SSL_ST_READ_HEADER;
968                 rr->off=0;
969                 }
970
971         if (type == SSL3_RT_HANDSHAKE)
972                 ssl3_finish_mac(s,buf,n);
973         return(n);
974 f_err:
975         ssl3_send_alert(s,SSL3_AL_FATAL,al);
976 err:
977         return(-1);
978         }
979
980 static int do_change_cipher_spec(SSL *s)
981         {
982         int i;
983         const char *sender;
984         int slen;
985
986         if (s->state & SSL_ST_ACCEPT)
987                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
988         else
989                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
990
991         if (s->s3->tmp.key_block == NULL)
992                 {
993                 s->session->cipher=s->s3->tmp.new_cipher;
994                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
995                 }
996
997         if (!s->method->ssl3_enc->change_cipher_state(s,i))
998                 return(0);
999
1000         /* we have to record the message digest at
1001          * this point so we can get it before we read
1002          * the finished message */
1003         if (s->state & SSL_ST_CONNECT)
1004                 {
1005                 sender=s->method->ssl3_enc->server_finished_label;
1006                 slen=s->method->ssl3_enc->server_finished_label_len;
1007                 }
1008         else
1009                 {
1010                 sender=s->method->ssl3_enc->client_finished_label;
1011                 slen=s->method->ssl3_enc->client_finished_label_len;
1012                 }
1013
1014         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1015                 &(s->s3->finish_dgst1),
1016                 &(s->s3->finish_dgst2),
1017                 sender,slen,s->s3->tmp.peer_finish_md);
1018
1019         return(1);
1020         }
1021
1022 /* send s->init_buf in records of type 'type' */
1023 int ssl3_do_write(SSL *s, int type)
1024         {
1025         int ret;
1026
1027         ret=ssl3_write_bytes(s,type,&s->init_buf->data[s->init_off],
1028                              s->init_num);
1029         if (ret == s->init_num)
1030                 return(1);
1031         if (ret < 0) return(-1);
1032         s->init_off+=ret;
1033         s->init_num-=ret;
1034         return(0);
1035         }
1036
1037 void ssl3_send_alert(SSL *s, int level, int desc)
1038         {
1039         /* Map tls/ssl alert value to correct one */
1040         desc=s->method->ssl3_enc->alert_value(desc);
1041         if (desc < 0) return;
1042         /* If a fatal one, remove from cache */
1043         if ((level == 2) && (s->session != NULL))
1044                 SSL_CTX_remove_session(s->ctx,s->session);
1045
1046         s->s3->alert_dispatch=1;
1047         s->s3->send_alert[0]=level;
1048         s->s3->send_alert[1]=desc;
1049         if (s->s3->wbuf.left == 0) /* data still being written out */
1050                 ssl3_dispatch_alert(s);
1051         /* else data is still being written out, we will get written
1052          * some time in the future */
1053         }
1054
1055 int ssl3_dispatch_alert(SSL *s)
1056         {
1057         int i,j;
1058         void (*cb)()=NULL;
1059
1060         s->s3->alert_dispatch=0;
1061         i=do_ssl3_write(s,SSL3_RT_ALERT,&s->s3->send_alert[0],2);
1062         if (i <= 0)
1063                 {
1064                 s->s3->alert_dispatch=1;
1065                 }
1066         else
1067                 {
1068                 /* If it is important, send it now.  If the message
1069                  * does not get sent due to non-blocking IO, we will
1070                  * not worry too much. */
1071                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1072                         (void)BIO_flush(s->wbio);
1073
1074                 if (s->info_callback != NULL)
1075                         cb=s->info_callback;
1076                 else if (s->ctx->info_callback != NULL)
1077                         cb=s->ctx->info_callback;
1078                 
1079                 if (cb != NULL)
1080                         {
1081                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1082                         cb(s,SSL_CB_WRITE_ALERT,j);
1083                         }
1084                 }
1085         return(i);
1086         }