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 /* 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 (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 /* Return up to 'len' payload bytes received in 'type' records.
 684  * 'type' is one of the following:
 685  *
 686  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 687  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 688  *   -  0 (during a shutdown, no data has to be returned)
 689  *
 690  * If we don't have stored data to work from, read a SSL/TLS record first
 691  * (possibly multiple records if we still don't have anything to return).
 692  *
 693  * This function must handle any surprises the peer may have for us, such as
 694  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 695  * a surprise, but handled as if it were), or renegotiation requests.
 696  * Also if record payloads contain fragments too small to process, we store
 697  * them until there is enough for the respective protocol (the record protocol
 698  * may use arbitrary fragmentation and even interleaving):
 699  *     Change cipher spec protocol
 700  *             just 1 byte needed, no need for keeping anything stored
 701  *     Alert protocol
 702  *             2 bytes needed (AlertLevel, AlertDescription)
 703  *     Handshake protocol
 704  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 705  *             to detect unexpected Client Hello and Hello Request messages
 706  *             here, anything else is handled by higher layers
 707  *     Application data protocol
 708  *             none of our business
 709  */
 710 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len)
 711         {
 712         int al,i,j,n,ret;
 713         SSL3_RECORD *rr;
 714         void (*cb)()=NULL;
 715         BIO *bio;
 716
 717         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 718                 if (!ssl3_setup_buffers(s))
 719                         return(-1);
 720
 721         if ((type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type)
 722                 {
 723                 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_INTERNAL_ERROR);
 724                 return -1;
 725                 }
 726
 727         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 728                 /* (partially) satisfy request from storage */
 729                 {
 730                 unsigned char *src = s->s3->handshake_fragment;
 731                 unsigned char *dst = buf;
 732
 733                 n = 0;
 734                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 735                         {
 736                         *dst++ = *src++;
 737                         len--; s->s3->handshake_fragment_len--;
 738                         n++;
 739                         }
 740                 /* move any remaining fragment bytes: */
 741                 for (i = 0; i < s->s3->handshake_fragment_len; i++)
 742                         s->s3->handshake_fragment[i] = *src++;
 743                 ssl3_finish_mac(s, buf, n);
 744                 return n;
 745         }
 746
 747         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 748
 749         if (!s->in_handshake && SSL_in_init(s))
 750                 {
 751                 /* type == SSL3_RT_APPLICATION_DATA */
 752                 i=s->handshake_func(s);
 753                 if (i < 0) return(i);
 754                 if (i == 0)
 755                         {
 756                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 757                         return(-1);
 758                         }
 759                 }
 760 start:
 761         s->rwstate=SSL_NOTHING;
 762
 763         /* s->s3->rrec.type         - is the type of record
 764          * s->s3->rrec.data,    - data
 765          * s->s3->rrec.off,     - offset into 'data' for next read
 766          * s->s3->rrec.length,  - number of bytes. */
 767         rr = &(s->s3->rrec);
 768
 769         /* get new packet */
 770         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 771                 {
 772                 ret=ssl3_get_record(s);
 773                 if (ret <= 0) return(ret);
 774                 }
 775
 776         /* we now have a packet which can be read and processed */
 777
 778         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 779                                        * reset by ssl3_get_finished */
 780                 && (rr->type != SSL3_RT_HANDSHAKE))
 781                 {
 782                 al=SSL_AD_UNEXPECTED_MESSAGE;
 783                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 784                 goto err;
 785                 }
 786
 787         /* If the other end has shutdown, throw anything we read away */
 788         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 789                 {
 790                 rr->length=0;
 791                 s->rwstate=SSL_NOTHING;
 792                 return(0);
 793                 }
 794
 795
 796         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 797                 {
 798                 /* make sure that we are not getting application data when we
 799                  * are doing a handshake for the first time */
 800                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 801                         (s->enc_read_ctx == NULL))
 802                         {
 803                         al=SSL_AD_UNEXPECTED_MESSAGE;
 804                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 805                         goto f_err;
 806                         }
 807
 808                 if (len <= 0) return(len);
 809
 810                 if ((unsigned int)len > rr->length)
 811                         n=rr->length;
 812                 else
 813                         n=len;
 814
 815                 memcpy(buf,&(rr->data[rr->off]),(unsigned int)n);
 816                 rr->length-=n;
 817                 rr->off+=n;
 818                 if (rr->length == 0)
 819                         {
 820                         s->rstate=SSL_ST_READ_HEADER;
 821                         rr->off=0;
 822                         }
 823
 824                 if (type == SSL3_RT_HANDSHAKE)
 825                         ssl3_finish_mac(s,buf,n);
 826                 return(n);
 827                 }
 828
 829
 830         /* If we get here, then type != rr->type; if we have a handshake
 831          * message, then it was unexpected (Hello Request or Client Hello). */
 832
 833         /* In case of record types for which we have 'fragment' storage,
 834          * fill that so that we can process the data at a fixed place.
 835          */
 836                 {
 837                 int dest_maxlen = 0;
 838                 unsigned char *dest;
 839                 int *dest_len;
 840
 841                 if (rr->type == SSL3_RT_HANDSHAKE)
 842                         {
 843                         dest_maxlen = sizeof s->s3->handshake_fragment;
 844                         dest = s->s3->handshake_fragment;
 845                         dest_len = &s->s3->handshake_fragment_len;
 846                         }
 847                 else if (rr->type == SSL3_RT_ALERT)
 848                         {
 849                         dest_maxlen = sizeof s->s3->alert_fragment;
 850                         dest = s->s3->alert_fragment;
 851                         dest_len = &s->s3->alert_fragment_len;
 852                         }
 853
 854                 if (dest_maxlen > 0)
 855                         {
 856                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
 857                         if (rr->length < n)
 858                                 n = rr->length; /* available bytes */
 859
 860                         /* now move 'n' bytes: */
 861                         while (n-- > 0)
 862                                 {
 863                                 dest[(*dest_len)++] = rr->data[rr->off++];
 864                                 rr->length--;
 865                                 }
 866
 867                         if (*dest_len < dest_maxlen)
 868                                 goto start; /* fragment was too small */
 869                         }
 870                 }
 871
 872         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
 873          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
 874          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
 875
 876         /* If we are a client, check for an incoming 'Hello Request': */
 877         if ((!s->server) &&
 878                 (s->s3->handshake_fragment_len >= 4) &&
 879                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
 880                 (s->session != NULL) && (s->session->cipher != NULL))
 881                 {
 882                 s->s3->handshake_fragment_len = 0;
 883
 884                 if ((s->s3->handshake_fragment[1] != 0) ||
 885                         (s->s3->handshake_fragment[2] != 0) ||
 886                         (s->s3->handshake_fragment[3] != 0))
 887                         {
 888                         al=SSL_AD_DECODE_ERROR;
 889                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
 890                         goto err;
 891                         }
 892
 893                 if (SSL_is_init_finished(s) &&
 894                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
 895                         !s->s3->renegotiate)
 896                         {
 897                         ssl3_renegotiate(s);
 898                         if (ssl3_renegotiate_check(s))
 899                                 {
 900                                 n=s->handshake_func(s);
 901                                 if (n < 0) return(n);
 902                                 if (n == 0)
 903                                         {
 904                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 905                                         return(-1);
 906                                         }
 907                                 }
 908                         }
 909                 /* we either finished a handshake or ignored the request,
 910                  * now try again to obtain the (application) data we were asked for */
 911                 goto start;
 912                 }
 913
 914         if (s->s3->alert_fragment_len >= 2)
 915                 {
 916                 i = s->s3->alert_fragment[0];
 917                 n = s->s3->alert_fragment[1];
 918
 919                 s->s3->alert_fragment_len = 0;
 920
 921                 if (s->info_callback != NULL)
 922                         cb=s->info_callback;
 923                 else if (s->ctx->info_callback != NULL)
 924                         cb=s->ctx->info_callback;
 925
 926                 if (cb != NULL)
 927                         {
 928                         j=(i<<8)|n;
 929                         cb(s,SSL_CB_READ_ALERT,j);
 930                         }
 931
 932                 if (i == 1) /* warning */
 933                         {
 934                         s->s3->warn_alert=n;
 935                         if (n == SSL_AD_CLOSE_NOTIFY)
 936                                 {
 937                                 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
 938                                 return(0);
 939                                 }
 940                         }
 941                 else if (i == 2) /* fatal */
 942                         {
 943                         char tmp[16];
 944
 945                         s->rwstate=SSL_NOTHING;
 946                         s->s3->fatal_alert=n;
 947                         SSLerr(SSL_F_SSL3_READ_BYTES,
 948                                 SSL_AD_REASON_OFFSET+n);
 949                         sprintf(tmp,"%d",n);
 950                         ERR_add_error_data(2,"SSL alert number ",tmp);
 951                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
 952                         SSL_CTX_remove_session(s->ctx,s->session);
 953                         return(0);
 954                         }
 955                 else
 956                         {
 957                         al=SSL_AD_ILLEGAL_PARAMETER;
 958                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
 959                         goto f_err;
 960                         }
 961
 962                 goto start;
 963                 }
 964
 965         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
 966                 {
 967                 s->rwstate=SSL_NOTHING;
 968                 rr->length=0;
 969                 return(0);
 970                 }
 971
 972         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
 973                 {
 974                 /* 'Change Cipher Spec' is just a single byte, so we know
 975                  * exactly what the record payload has to look like */
 976                 if (    (rr->length != 1) || (rr->off != 0) ||
 977                         (rr->data[0] != SSL3_MT_CCS))
 978                         {
 979                         i=SSL_AD_ILLEGAL_PARAMETER;
 980                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
 981                         goto err;
 982                         }
 983
 984                 rr->length=0;
 985                 s->s3->change_cipher_spec=1;
 986                 if (!do_change_cipher_spec(s))
 987                         goto err;
 988                 else
 989                         goto start;
 990                 }
 991
 992         /* Unexpected handshake message (Client Hello, or protocol violation) */
 993         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
 994                 {
 995                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
 996                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
 997                         {
 998                         s->state=SSL_ST_BEFORE|(s->server)
 999                                 ?SSL_ST_ACCEPT
1000                                 :SSL_ST_CONNECT;
1001                         s->new_session=1;
1002                         }
1003                 n=s->handshake_func(s);
1004                 if (n < 0) return(n);
1005                 if (n == 0)
1006                         {
1007                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1008                         return(-1);
1009                         }
1010
1011                 /* In the case where we try to read application data
1012                  * the first time, but we trigger an SSL handshake, we
1013                  * return -1 with the retry option set.  I do this
1014                  * otherwise renegotiation can cause nasty problems
1015                  * in the non-blocking world */
1016
1017                 s->rwstate=SSL_READING;
1018                 bio=SSL_get_rbio(s);
1019                 BIO_clear_retry_flags(bio);
1020                 BIO_set_retry_read(bio);
1021                 return(-1);
1022                 }
1023
1024         switch (rr->type)
1025                 {
1026         default:
1027 #ifndef NO_TLS
1028                 /* TLS just ignores unknown message types */
1029                 if (s->version == TLS1_VERSION)
1030                         {
1031                         goto start;
1032                         }
1033 #endif
1034                 al=SSL_AD_UNEXPECTED_MESSAGE;
1035                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1036                 goto f_err;
1037         case SSL3_RT_CHANGE_CIPHER_SPEC:
1038         case SSL3_RT_ALERT:
1039         case SSL3_RT_HANDSHAKE:
1040                 /* we already handled all of these, with the possible exception
1041                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1042                  * should not happen when type != rr->type */
1043                 al=SSL_AD_UNEXPECTED_MESSAGE;
1044                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_INTERNAL_ERROR);
1045                 goto f_err;
1046         case SSL3_RT_APPLICATION_DATA:
1047                 /* At this point, we were expecting handshake data,
1048                  * but have application data.  If the library was
1049                  * running inside ssl3_read() (i.e. in_read_app_data
1050                  * is set) and it makes sense to read application data
1051                  * at this point (session renegotation not yet started),
1052                  * we will indulge it.
1053                  */
1054                 if (s->s3->in_read_app_data &&
1055                         (s->s3->total_renegotiations != 0) &&
1056                         ((
1057                                 (s->state & SSL_ST_CONNECT) &&
1058                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1059                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1060                                 ) || (
1061                                         (s->state & SSL_ST_ACCEPT) &&
1062                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1063                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1064                                         )
1065                                 ))
1066                         {
1067                         s->s3->in_read_app_data=0;
1068                         return(-1);
1069                         }
1070                 else
1071                         {
1072                         al=SSL_AD_UNEXPECTED_MESSAGE;
1073                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1074                         goto f_err;
1075                         }
1076                 }
1077         /* not reached */
1078
1079 f_err:
1080         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1081 err:
1082         return(-1);
1083         }
1084
1085 static int do_change_cipher_spec(SSL *s)
1086         {
1087         int i;
1088         const char *sender;
1089         int slen;
1090
1091         if (s->state & SSL_ST_ACCEPT)
1092                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1093         else
1094                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1095
1096         if (s->s3->tmp.key_block == NULL)
1097                 {
1098                 s->session->cipher=s->s3->tmp.new_cipher;
1099                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1100                 }
1101
1102         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1103                 return(0);
1104
1105         /* we have to record the message digest at
1106          * this point so we can get it before we read
1107          * the finished message */
1108         if (s->state & SSL_ST_CONNECT)
1109                 {
1110                 sender=s->method->ssl3_enc->server_finished_label;
1111                 slen=s->method->ssl3_enc->server_finished_label_len;
1112                 }
1113         else
1114                 {
1115                 sender=s->method->ssl3_enc->client_finished_label;
1116                 slen=s->method->ssl3_enc->client_finished_label_len;
1117                 }
1118
1119         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1120                 &(s->s3->finish_dgst1),
1121                 &(s->s3->finish_dgst2),
1122                 sender,slen,s->s3->tmp.peer_finish_md);
1123
1124         return(1);
1125         }
1126
1127 /* send s->init_buf in records of type 'type' */
1128 int ssl3_do_write(SSL *s, int type)
1129         {
1130         int ret;
1131
1132         ret=ssl3_write_bytes(s,type,&s->init_buf->data[s->init_off],
1133                              s->init_num);
1134         if (ret == s->init_num)
1135                 return(1);
1136         if (ret < 0) return(-1);
1137         s->init_off+=ret;
1138         s->init_num-=ret;
1139         return(0);
1140         }
1141
1142 void ssl3_send_alert(SSL *s, int level, int desc)
1143         {
1144         /* Map tls/ssl alert value to correct one */
1145         desc=s->method->ssl3_enc->alert_value(desc);
1146         if (desc < 0) return;
1147         /* If a fatal one, remove from cache */
1148         if ((level == 2) && (s->session != NULL))
1149                 SSL_CTX_remove_session(s->ctx,s->session);
1150
1151         s->s3->alert_dispatch=1;
1152         s->s3->send_alert[0]=level;
1153         s->s3->send_alert[1]=desc;
1154         if (s->s3->wbuf.left == 0) /* data still being written out */
1155                 ssl3_dispatch_alert(s);
1156         /* else data is still being written out, we will get written
1157          * some time in the future */
1158         }
1159
1160 int ssl3_dispatch_alert(SSL *s)
1161         {
1162         int i,j;
1163         void (*cb)()=NULL;
1164
1165         s->s3->alert_dispatch=0;
1166         i=do_ssl3_write(s,SSL3_RT_ALERT,&s->s3->send_alert[0],2);
1167         if (i <= 0)
1168                 {
1169                 s->s3->alert_dispatch=1;
1170                 }
1171         else
1172                 {
1173                 /* If it is important, send it now.  If the message
1174                  * does not get sent due to non-blocking IO, we will
1175                  * not worry too much. */
1176                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1177                         (void)BIO_flush(s->wbio);
1178
1179                 if (s->info_callback != NULL)
1180                         cb=s->info_callback;
1181                 else if (s->ctx->info_callback != NULL)
1182                         cb=s->ctx->info_callback;
1183
1184                 if (cb != NULL)
1185                         {
1186                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1187                         cb(s,SSL_CB_WRITE_ALERT,j);
1188                         }
1189                 }
1190         return(i);
1191         }