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) 1998-2000 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 /* used only by ssl3_get_record */
 129 static int ssl3_read_n(SSL *s, int n, int max, int extend)
 130         {
 131         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
 132          * packet by another n bytes.
 133          * The packet will be in the sub-array of s->s3->rbuf.buf specified
 134          * by s->packet and s->packet_length.
 135          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
 136          * [plus s->packet_length bytes if extend == 1].)
 137          */
 138         int i,off,newb;
 139
 140         if (!extend)
 141                 {
 142                 /* start with empty packet ... */
 143                 if (s->s3->rbuf.left == 0)
 144                         s->s3->rbuf.offset = 0;
 145                 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
 146                 s->packet_length = 0;
 147                 /* ... now we can act as if 'extend' was set */
 148                 }
 149
 150         /* if there is enough in the buffer from a previous read, take some */
 151         if (s->s3->rbuf.left >= (int)n)
 152                 {
 153                 s->packet_length+=n;
 154                 s->s3->rbuf.left-=n;
 155                 s->s3->rbuf.offset+=n;
 156                 return(n);
 157                 }
 158
 159         /* else we need to read more data */
 160         if (!s->read_ahead)
 161                 max=n;
 162
 163         {
 164                 /* avoid buffer overflow */
 165                 int max_max = SSL3_RT_MAX_PACKET_SIZE - s->packet_length;
 166                 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 167                         max_max += SSL3_RT_MAX_EXTRA;
 168                 if (max > max_max)
 169                         max = max_max;
 170         }
 171         if (n > max) /* does not happen */
 172                 {
 173                 SSLerr(SSL_F_SSL3_READ_N,SSL_R_INTERNAL_ERROR);
 174                 return -1;
 175                 }
 176
 177         off = s->packet_length;
 178         newb = s->s3->rbuf.left;
 179         /* Move any available bytes to front of buffer:
 180          * 'off' bytes already pointed to by 'packet',
 181          * 'newb' extra ones at the end */
 182         if (s->packet != s->s3->rbuf.buf)
 183                 {
 184                 /*  off > 0 */
 185                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
 186                 s->packet = s->s3->rbuf.buf;
 187                 }
 188
 189         while (newb < n)
 190                 {
 191                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
 192                  * to read in more until we have off+n (up to off+max if possible) */
 193
 194                 clear_sys_error();
 195                 if (s->rbio != NULL)
 196                         {
 197                         s->rwstate=SSL_READING;
 198                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
 199                         }
 200                 else
 201                         {
 202                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 203                         i = -1;
 204                         }
 205
 206                 if (i <= 0)
 207                         {
 208                         s->s3->rbuf.left = newb;
 209                         return(i);
 210                         }
 211                 newb+=i;
 212                 }
 213
 214         /* done reading, now the book-keeping */
 215         s->s3->rbuf.offset = off + n;
 216         s->s3->rbuf.left = newb - n;
 217         s->packet_length += n;
 218         s->rwstate=SSL_NOTHING;
 219         return(n);
 220         }
 221
 222 /* Call this to get a new input record.
 223  * It will return <= 0 if more data is needed, normally due to an error
 224  * or non-blocking IO.
 225  * When it finishes, one packet has been decoded and can be found in
 226  * ssl->s3->rrec.type    - is the type of record
 227  * ssl->s3->rrec.data,   - data
 228  * ssl->s3->rrec.length, - number of bytes
 229  */
 230 /* used only by ssl3_read_bytes */
 231 static int ssl3_get_record(SSL *s)
 232         {
 233         int ssl_major,ssl_minor,al;
 234         int n,i,ret= -1;
 235         SSL3_RECORD *rr;
 236         SSL_SESSION *sess;
 237         unsigned char *p;
 238         unsigned char md[EVP_MAX_MD_SIZE];
 239         short version;
 240         unsigned int mac_size;
 241         int clear=0,extra;
 242
 243         rr= &(s->s3->rrec);
 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 believe */
 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 ((i == (int)n) ||
 511                         (type == SSL3_RT_APPLICATION_DATA &&
 512                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 513                         {
 514                         return(tot+i);
 515                         }
 516
 517                 n-=i;
 518                 tot+=i;
 519                 }
 520         }
 521
 522 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 523                          unsigned int len)
 524         {
 525         unsigned char *p,*plen;
 526         int i,mac_size,clear=0;
 527         SSL3_RECORD *wr;
 528         SSL3_BUFFER *wb;
 529         SSL_SESSION *sess;
 530
 531         /* first check is there is a SSL3_RECORD still being written
 532          * out.  This will happen with non blocking IO */
 533         if (s->s3->wbuf.left != 0)
 534                 return(ssl3_write_pending(s,type,buf,len));
 535
 536         /* If we have an alert to send, lets send it */
 537         if (s->s3->alert_dispatch)
 538                 {
 539                 i=ssl3_dispatch_alert(s);
 540                 if (i <= 0)
 541                         return(i);
 542                 /* if it went, fall through and send more stuff */
 543                 }
 544
 545         if (len == 0) return(len);
 546
 547         wr= &(s->s3->wrec);
 548         wb= &(s->s3->wbuf);
 549         sess=s->session;
 550
 551         if (    (sess == NULL) ||
 552                 (s->enc_write_ctx == NULL) ||
 553                 (s->write_hash == NULL))
 554                 clear=1;
 555
 556         if (clear)
 557                 mac_size=0;
 558         else
 559                 mac_size=EVP_MD_size(s->write_hash);
 560
 561         p=wb->buf;
 562
 563         /* write the header */
 564         *(p++)=type&0xff;
 565         wr->type=type;
 566
 567         *(p++)=(s->version>>8);
 568         *(p++)=s->version&0xff;
 569
 570         /* record where we are to write out packet length */
 571         plen=p;
 572         p+=2;
 573
 574         /* lets setup the record stuff. */
 575         wr->data=p;
 576         wr->length=(int)len;
 577         wr->input=(unsigned char *)buf;
 578
 579         /* we now 'read' from wr->input, wr->length bytes into
 580          * wr->data */
 581
 582         /* first we compress */
 583         if (s->compress != NULL)
 584                 {
 585                 if (!do_compress(s))
 586                         {
 587                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 588                         goto err;
 589                         }
 590                 }
 591         else
 592                 {
 593                 memcpy(wr->data,wr->input,wr->length);
 594                 wr->input=wr->data;
 595                 }
 596
 597         /* we should still have the output to wr->data and the input
 598          * from wr->input.  Length should be wr->length.
 599          * wr->data still points in the wb->buf */
 600
 601         if (mac_size != 0)
 602                 {
 603                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
 604                 wr->length+=mac_size;
 605                 wr->input=p;
 606                 wr->data=p;
 607                 }
 608
 609         /* ssl3_enc can only have an error on read */
 610         s->method->ssl3_enc->enc(s,1);
 611
 612         /* record length after mac and block padding */
 613         s2n(wr->length,plen);
 614
 615         /* we should now have
 616          * wr->data pointing to the encrypted data, which is
 617          * wr->length long */
 618         wr->type=type; /* not needed but helps for debugging */
 619         wr->length+=SSL3_RT_HEADER_LENGTH;
 620
 621         /* Now lets setup wb */
 622         wb->left=wr->length;
 623         wb->offset=0;
 624
 625         s->s3->wpend_tot=len;
 626         s->s3->wpend_buf=buf;
 627         s->s3->wpend_type=type;
 628         s->s3->wpend_ret=len;
 629
 630         /* we now just need to write the buffer */
 631         return(ssl3_write_pending(s,type,buf,len));
 632 err:
 633         return(-1);
 634         }
 635
 636 /* if s->s3->wbuf.left != 0, we need to call this */
 637 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 638                               unsigned int len)
 639         {
 640         int i;
 641
 642 /* XXXX */
 643         if ((s->s3->wpend_tot > (int)len)
 644                 || ((s->s3->wpend_buf != buf) &&
 645                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 646                 || (s->s3->wpend_type != type))
 647                 {
 648                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 649                 return(-1);
 650                 }
 651
 652         for (;;)
 653                 {
 654                 clear_sys_error();
 655                 if (s->wbio != NULL)
 656                         {
 657                         s->rwstate=SSL_WRITING;
 658                         i=BIO_write(s->wbio,
 659                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
 660                                 (unsigned int)s->s3->wbuf.left);
 661                         }
 662                 else
 663                         {
 664                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 665                         i= -1;
 666                         }
 667                 if (i == s->s3->wbuf.left)
 668                         {
 669                         s->s3->wbuf.left=0;
 670                         s->rwstate=SSL_NOTHING;
 671                         return(s->s3->wpend_ret);
 672                         }
 673                 else if (i <= 0)
 674                         return(i);
 675                 s->s3->wbuf.offset+=i;
 676                 s->s3->wbuf.left-=i;
 677                 }
 678         }
 679
 680 /* Return up to 'len' payload bytes received in 'type' records.
 681  * 'type' is one of the following:
 682  *
 683  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 684  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 685  *   -  0 (during a shutdown, no data has to be returned)
 686  *
 687  * If we don't have stored data to work from, read a SSL/TLS record first
 688  * (possibly multiple records if we still don't have anything to return).
 689  *
 690  * This function must handle any surprises the peer may have for us, such as
 691  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 692  * a surprise, but handled as if it were), or renegotiation requests.
 693  * Also if record payloads contain fragments too small to process, we store
 694  * them until there is enough for the respective protocol (the record protocol
 695  * may use arbitrary fragmentation and even interleaving):
 696  *     Change cipher spec protocol
 697  *             just 1 byte needed, no need for keeping anything stored
 698  *     Alert protocol
 699  *             2 bytes needed (AlertLevel, AlertDescription)
 700  *     Handshake protocol
 701  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 702  *             to detect unexpected Client Hello and Hello Request messages
 703  *             here, anything else is handled by higher layers
 704  *     Application data protocol
 705  *             none of our business
 706  */
 707 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len)
 708         {
 709         int al,i,j,ret;
 710         unsigned int n;
 711         SSL3_RECORD *rr;
 712         void (*cb)()=NULL;
 713
 714         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 715                 if (!ssl3_setup_buffers(s))
 716                         return(-1);
 717
 718         if ((type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type)
 719                 {
 720                 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_INTERNAL_ERROR);
 721                 return -1;
 722                 }
 723
 724         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 725                 /* (partially) satisfy request from storage */
 726                 {
 727                 unsigned char *src = s->s3->handshake_fragment;
 728                 unsigned char *dst = buf;
 729                 unsigned int k;
 730
 731                 n = 0;
 732                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 733                         {
 734                         *dst++ = *src++;
 735                         len--; s->s3->handshake_fragment_len--;
 736                         n++;
 737                         }
 738                 /* move any remaining fragment bytes: */
 739                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
 740                         s->s3->handshake_fragment[k] = *src++;
 741                 return n;
 742         }
 743
 744         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 745
 746         if (!s->in_handshake && SSL_in_init(s))
 747                 {
 748                 /* type == SSL3_RT_APPLICATION_DATA */
 749                 i=s->handshake_func(s);
 750                 if (i < 0) return(i);
 751                 if (i == 0)
 752                         {
 753                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 754                         return(-1);
 755                         }
 756                 }
 757 start:
 758         s->rwstate=SSL_NOTHING;
 759
 760         /* s->s3->rrec.type         - is the type of record
 761          * s->s3->rrec.data,    - data
 762          * s->s3->rrec.off,     - offset into 'data' for next read
 763          * s->s3->rrec.length,  - number of bytes. */
 764         rr = &(s->s3->rrec);
 765
 766         /* get new packet */
 767         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 768                 {
 769                 ret=ssl3_get_record(s);
 770                 if (ret <= 0) return(ret);
 771                 }
 772
 773         /* we now have a packet which can be read and processed */
 774
 775         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 776                                        * reset by ssl3_get_finished */
 777                 && (rr->type != SSL3_RT_HANDSHAKE))
 778                 {
 779                 al=SSL_AD_UNEXPECTED_MESSAGE;
 780                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 781                 goto err;
 782                 }
 783
 784         /* If the other end has shutdown, throw anything we read away */
 785         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 786                 {
 787                 rr->length=0;
 788                 s->rwstate=SSL_NOTHING;
 789                 return(0);
 790                 }
 791
 792
 793         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 794                 {
 795                 /* make sure that we are not getting application data when we
 796                  * are doing a handshake for the first time */
 797                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 798                         (s->enc_read_ctx == NULL))
 799                         {
 800                         al=SSL_AD_UNEXPECTED_MESSAGE;
 801                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 802                         goto f_err;
 803                         }
 804
 805                 if (len <= 0) return(len);
 806
 807                 if ((unsigned int)len > rr->length)
 808                         n = rr->length;
 809                 else
 810                         n = (unsigned int)len;
 811
 812                 memcpy(buf,&(rr->data[rr->off]),n);
 813                 rr->length-=n;
 814                 rr->off+=n;
 815                 if (rr->length == 0)
 816                         {
 817                         s->rstate=SSL_ST_READ_HEADER;
 818                         rr->off=0;
 819                         }
 820                 return(n);
 821                 }
 822
 823
 824         /* If we get here, then type != rr->type; if we have a handshake
 825          * message, then it was unexpected (Hello Request or Client Hello). */
 826
 827         /* In case of record types for which we have 'fragment' storage,
 828          * fill that so that we can process the data at a fixed place.
 829          */
 830                 {
 831                 unsigned int dest_maxlen = 0;
 832                 unsigned char *dest = NULL;
 833                 unsigned int *dest_len = NULL;
 834
 835                 if (rr->type == SSL3_RT_HANDSHAKE)
 836                         {
 837                         dest_maxlen = sizeof s->s3->handshake_fragment;
 838                         dest = s->s3->handshake_fragment;
 839                         dest_len = &s->s3->handshake_fragment_len;
 840                         }
 841                 else if (rr->type == SSL3_RT_ALERT)
 842                         {
 843                         dest_maxlen = sizeof s->s3->alert_fragment;
 844                         dest = s->s3->alert_fragment;
 845                         dest_len = &s->s3->alert_fragment_len;
 846                         }
 847
 848                 if (dest_maxlen > 0)
 849                         {
 850                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
 851                         if (rr->length < n)
 852                                 n = rr->length; /* available bytes */
 853
 854                         /* now move 'n' bytes: */
 855                         while (n-- > 0)
 856                                 {
 857                                 dest[(*dest_len)++] = rr->data[rr->off++];
 858                                 rr->length--;
 859                                 }
 860
 861                         if (*dest_len < dest_maxlen)
 862                                 goto start; /* fragment was too small */
 863                         }
 864                 }
 865
 866         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
 867          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
 868          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
 869
 870         /* If we are a client, check for an incoming 'Hello Request': */
 871         if ((!s->server) &&
 872                 (s->s3->handshake_fragment_len >= 4) &&
 873                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
 874                 (s->session != NULL) && (s->session->cipher != NULL))
 875                 {
 876                 s->s3->handshake_fragment_len = 0;
 877
 878                 if ((s->s3->handshake_fragment[1] != 0) ||
 879                         (s->s3->handshake_fragment[2] != 0) ||
 880                         (s->s3->handshake_fragment[3] != 0))
 881                         {
 882                         al=SSL_AD_DECODE_ERROR;
 883                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
 884                         goto err;
 885                         }
 886
 887                 if (SSL_is_init_finished(s) &&
 888                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
 889                         !s->s3->renegotiate)
 890                         {
 891                         ssl3_renegotiate(s);
 892                         if (ssl3_renegotiate_check(s))
 893                                 {
 894                                 i=s->handshake_func(s);
 895                                 if (i < 0) return(i);
 896                                 if (i == 0)
 897                                         {
 898                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 899                                         return(-1);
 900                                         }
 901
 902                                 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
 903                                         {
 904                                         BIO *bio;
 905                                         /* In the case where we try to read application data
 906                                          * the first time, but we trigger an SSL handshake, we
 907                                          * return -1 with the retry option set.  I do this
 908                                          * otherwise renegotiation can cause nasty problems
 909                                          * in the blocking world */ /* ? */
 910                                         s->rwstate=SSL_READING;
 911                                         bio=SSL_get_rbio(s);
 912                                         BIO_clear_retry_flags(bio);
 913                                         BIO_set_retry_read(bio);
 914                                         return(-1);
 915                                         }
 916                                 }
 917                         }
 918                 /* we either finished a handshake or ignored the request,
 919                  * now try again to obtain the (application) data we were asked for */
 920                 goto start;
 921                 }
 922
 923         if (s->s3->alert_fragment_len >= 2)
 924                 {
 925                 int alert_level = s->s3->alert_fragment[0];
 926                 int alert_descr = s->s3->alert_fragment[1];
 927
 928                 s->s3->alert_fragment_len = 0;
 929
 930                 if (s->info_callback != NULL)
 931                         cb=s->info_callback;
 932                 else if (s->ctx->info_callback != NULL)
 933                         cb=s->ctx->info_callback;
 934
 935                 if (cb != NULL)
 936                         {
 937                         j = (alert_level << 8) | alert_descr;
 938                         cb(s, SSL_CB_READ_ALERT, j);
 939                         }
 940
 941                 if (alert_level == 1) /* warning */
 942                         {
 943                         s->s3->warn_alert = alert_descr;
 944                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
 945                                 {
 946                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
 947                                 return(0);
 948                                 }
 949                         }
 950                 else if (alert_level == 2) /* fatal */
 951                         {
 952                         char tmp[16];
 953
 954                         s->rwstate=SSL_NOTHING;
 955                         s->s3->fatal_alert = alert_descr;
 956                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
 957                         sprintf(tmp,"%d",alert_descr);
 958                         ERR_add_error_data(2,"SSL alert number ",tmp);
 959                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
 960                         SSL_CTX_remove_session(s->ctx,s->session);
 961                         return(0);
 962                         }
 963                 else
 964                         {
 965                         al=SSL_AD_ILLEGAL_PARAMETER;
 966                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
 967                         goto f_err;
 968                         }
 969
 970                 goto start;
 971                 }
 972
 973         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
 974                 {
 975                 s->rwstate=SSL_NOTHING;
 976                 rr->length=0;
 977                 return(0);
 978                 }
 979
 980         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
 981                 {
 982                 /* 'Change Cipher Spec' is just a single byte, so we know
 983                  * exactly what the record payload has to look like */
 984                 if (    (rr->length != 1) || (rr->off != 0) ||
 985                         (rr->data[0] != SSL3_MT_CCS))
 986                         {
 987                         i=SSL_AD_ILLEGAL_PARAMETER;
 988                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
 989                         goto err;
 990                         }
 991
 992                 rr->length=0;
 993                 s->s3->change_cipher_spec=1;
 994                 if (!do_change_cipher_spec(s))
 995                         goto err;
 996                 else
 997                         goto start;
 998                 }
 999
1000         /* Unexpected handshake message (Client Hello, or protocol violation) */
1001         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1002                 {
1003                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1004                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1005                         {
1006 #if 0 /* worked only because C operator preferences are not as expected (and
1007        * because this is not really needed for clients except for detecting
1008        * protocol violations): */
1009                         s->state=SSL_ST_BEFORE|(s->server)
1010                                 ?SSL_ST_ACCEPT
1011                                 :SSL_ST_CONNECT;
1012 #else
1013                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1014 #endif
1015                         s->new_session=1;
1016                         }
1017                 i=s->handshake_func(s);
1018                 if (i < 0) return(i);
1019                 if (i == 0)
1020                         {
1021                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1022                         return(-1);
1023                         }
1024
1025                 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1026                         {
1027                         BIO *bio;
1028                         /* In the case where we try to read application data
1029                          * the first time, but we trigger an SSL handshake, we
1030                          * return -1 with the retry option set.  I do this
1031                          * otherwise renegotiation can cause nasty problems
1032                          * in the blocking world */ /* ? */
1033                         s->rwstate=SSL_READING;
1034                         bio=SSL_get_rbio(s);
1035                         BIO_clear_retry_flags(bio);
1036                         BIO_set_retry_read(bio);
1037                         return(-1);
1038                         }
1039                 goto start;
1040                 }
1041
1042         switch (rr->type)
1043                 {
1044         default:
1045 #ifndef NO_TLS
1046                 /* TLS just ignores unknown message types */
1047                 if (s->version == TLS1_VERSION)
1048                         {
1049                         goto start;
1050                         }
1051 #endif
1052                 al=SSL_AD_UNEXPECTED_MESSAGE;
1053                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1054                 goto f_err;
1055         case SSL3_RT_CHANGE_CIPHER_SPEC:
1056         case SSL3_RT_ALERT:
1057         case SSL3_RT_HANDSHAKE:
1058                 /* we already handled all of these, with the possible exception
1059                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1060                  * should not happen when type != rr->type */
1061                 al=SSL_AD_UNEXPECTED_MESSAGE;
1062                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_INTERNAL_ERROR);
1063                 goto f_err;
1064         case SSL3_RT_APPLICATION_DATA:
1065                 /* At this point, we were expecting handshake data,
1066                  * but have application data.  If the library was
1067                  * running inside ssl3_read() (i.e. in_read_app_data
1068                  * is set) and it makes sense to read application data
1069                  * at this point (session renegotiation not yet started),
1070                  * we will indulge it.
1071                  */
1072                 if (s->s3->in_read_app_data &&
1073                         (s->s3->total_renegotiations != 0) &&
1074                         ((
1075                                 (s->state & SSL_ST_CONNECT) &&
1076                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1077                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1078                                 ) || (
1079                                         (s->state & SSL_ST_ACCEPT) &&
1080                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1081                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1082                                         )
1083                                 ))
1084                         {
1085                         s->s3->in_read_app_data=0;
1086                         return(-1);
1087                         }
1088                 else
1089                         {
1090                         al=SSL_AD_UNEXPECTED_MESSAGE;
1091                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1092                         goto f_err;
1093                         }
1094                 }
1095         /* not reached */
1096
1097 f_err:
1098         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1099 err:
1100         return(-1);
1101         }
1102
1103 static int do_change_cipher_spec(SSL *s)
1104         {
1105         int i;
1106         const char *sender;
1107         int slen;
1108
1109         if (s->state & SSL_ST_ACCEPT)
1110                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1111         else
1112                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1113
1114         if (s->s3->tmp.key_block == NULL)
1115                 {
1116                 s->session->cipher=s->s3->tmp.new_cipher;
1117                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1118                 }
1119
1120         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1121                 return(0);
1122
1123         /* we have to record the message digest at
1124          * this point so we can get it before we read
1125          * the finished message */
1126         if (s->state & SSL_ST_CONNECT)
1127                 {
1128                 sender=s->method->ssl3_enc->server_finished_label;
1129                 slen=s->method->ssl3_enc->server_finished_label_len;
1130                 }
1131         else
1132                 {
1133                 sender=s->method->ssl3_enc->client_finished_label;
1134                 slen=s->method->ssl3_enc->client_finished_label_len;
1135                 }
1136
1137         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1138                 &(s->s3->finish_dgst1),
1139                 &(s->s3->finish_dgst2),
1140                 sender,slen,s->s3->tmp.peer_finish_md);
1141
1142         return(1);
1143         }
1144
1145 void ssl3_send_alert(SSL *s, int level, int desc)
1146         {
1147         /* Map tls/ssl alert value to correct one */
1148         desc=s->method->ssl3_enc->alert_value(desc);
1149         if (desc < 0) return;
1150         /* If a fatal one, remove from cache */
1151         if ((level == 2) && (s->session != NULL))
1152                 SSL_CTX_remove_session(s->ctx,s->session);
1153
1154         s->s3->alert_dispatch=1;
1155         s->s3->send_alert[0]=level;
1156         s->s3->send_alert[1]=desc;
1157         if (s->s3->wbuf.left == 0) /* data still being written out */
1158                 ssl3_dispatch_alert(s);
1159         /* else data is still being written out, we will get written
1160          * some time in the future */
1161         }
1162
1163 int ssl3_dispatch_alert(SSL *s)
1164         {
1165         int i,j;
1166         void (*cb)()=NULL;
1167
1168         s->s3->alert_dispatch=0;
1169         i=do_ssl3_write(s,SSL3_RT_ALERT,&s->s3->send_alert[0],2);
1170         if (i <= 0)
1171                 {
1172                 s->s3->alert_dispatch=1;
1173                 }
1174         else
1175                 {
1176                 /* If it is important, send it now.  If the message
1177                  * does not get sent due to non-blocking IO, we will
1178                  * not worry too much. */
1179                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1180                         (void)BIO_flush(s->wbio);
1181
1182                 if (s->info_callback != NULL)
1183                         cb=s->info_callback;
1184                 else if (s->ctx->info_callback != NULL)
1185                         cb=s->ctx->info_callback;
1186
1187                 if (cb != NULL)
1188                         {
1189                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1190                         cb(s,SSL_CB_WRITE_ALERT,j);
1191                         }
1192                 }
1193         return(i);
1194         }