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) 1998-2002 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 "ssl_locl.h"
 116 #include <openssl/evp.h>
 117 #include <openssl/buffer.h>
 118
 119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 120                          unsigned int len, int create_empty_fragment);
 121 static int ssl3_get_record(SSL *s);
 122
 123 int ssl3_read_n(SSL *s, int n, int max, int extend)
 124         {
 125         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
 126          * packet by another n bytes.
 127          * The packet will be in the sub-array of s->s3->rbuf.buf specified
 128          * by s->packet and s->packet_length.
 129          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
 130          * [plus s->packet_length bytes if extend == 1].)
 131          */
 132         int i,off,newb;
 133
 134         if (!extend)
 135                 {
 136                 /* start with empty packet ... */
 137                 if (s->s3->rbuf.left == 0)
 138                         s->s3->rbuf.offset = 0;
 139                 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
 140                 s->packet_length = 0;
 141                 /* ... now we can act as if 'extend' was set */
 142                 }
 143
 144         /* For DTLS/UDP reads should not span multiple packets
 145          * because the read operation returns the whole packet
 146          * at once (as long as it fits into the buffer). */
 147         if (SSL_version(s) == DTLS1_VERSION)
 148                 {
 149                 if ( s->s3->rbuf.left > 0 && n > s->s3->rbuf.left)
 150                         n = s->s3->rbuf.left;
 151                 }
 152
 153         /* if there is enough in the buffer from a previous read, take some */
 154         if (s->s3->rbuf.left >= (int)n)
 155                 {
 156                 s->packet_length+=n;
 157                 s->s3->rbuf.left-=n;
 158                 s->s3->rbuf.offset+=n;
 159                 return(n);
 160                 }
 161
 162         /* else we need to read more data */
 163         if (!s->read_ahead)
 164                 max=n;
 165
 166         {
 167                 /* avoid buffer overflow */
 168                 int max_max = s->s3->rbuf.len - s->packet_length;
 169                 if (max > max_max)
 170                         max = max_max;
 171         }
 172         if (n > max) /* does not happen */
 173                 {
 174                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 175                 return -1;
 176                 }
 177
 178         off = s->packet_length;
 179         newb = s->s3->rbuf.left;
 180         /* Move any available bytes to front of buffer:
 181          * 'off' bytes already pointed to by 'packet',
 182          * 'newb' extra ones at the end */
 183         if (s->packet != s->s3->rbuf.buf)
 184                 {
 185                 /*  off > 0 */
 186                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
 187                 s->packet = s->s3->rbuf.buf;
 188                 }
 189
 190         while (newb < n)
 191                 {
 192                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
 193                  * to read in more until we have off+n (up to off+max if possible) */
 194
 195                 clear_sys_error();
 196                 if (s->rbio != NULL)
 197                         {
 198                         s->rwstate=SSL_READING;
 199                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
 200                         }
 201                 else
 202                         {
 203                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 204                         i = -1;
 205                         }
 206
 207                 if (i <= 0)
 208                         {
 209                         s->s3->rbuf.left = newb;
 210                         return(i);
 211                         }
 212                 newb+=i;
 213                 /* reads should *never* span multiple packets for DTLS because
 214                  * the underlying transport protocol is message oriented as opposed
 215                  * to byte oriented as in the TLS case. */
 216                 if (SSL_version(s) == DTLS1_VERSION)
 217                         {
 218                         if (n > newb)
 219                                 n = newb; /* makes the while condition false */
 220                         }
 221                 }
 222
 223         /* done reading, now the book-keeping */
 224         s->s3->rbuf.offset = off + n;
 225         s->s3->rbuf.left = newb - n;
 226         s->packet_length += n;
 227         s->rwstate=SSL_NOTHING;
 228         return(n);
 229         }
 230
 231 /* Call this to get a new input record.
 232  * It will return <= 0 if more data is needed, normally due to an error
 233  * or non-blocking IO.
 234  * When it finishes, one packet has been decoded and can be found in
 235  * ssl->s3->rrec.type    - is the type of record
 236  * ssl->s3->rrec.data,   - data
 237  * ssl->s3->rrec.length, - number of bytes
 238  */
 239 /* used only by ssl3_read_bytes */
 240 static int ssl3_get_record(SSL *s)
 241         {
 242         int ssl_major,ssl_minor,al;
 243         int enc_err,n,i,ret= -1;
 244         SSL3_RECORD *rr;
 245         SSL_SESSION *sess;
 246         unsigned char *p;
 247         unsigned char md[EVP_MAX_MD_SIZE];
 248         short version;
 249         unsigned mac_size, orig_len;
 250         size_t extra;
 251
 252         rr= &(s->s3->rrec);
 253         sess=s->session;
 254
 255         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 256                 extra=SSL3_RT_MAX_EXTRA;
 257         else
 258                 extra=0;
 259         if (extra != s->s3->rbuf.len - SSL3_RT_MAX_PACKET_SIZE)
 260                 {
 261                 /* actually likely an application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
 262                  * set after ssl3_setup_buffers() was done */
 263                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
 264                 return -1;
 265                 }
 266
 267 again:
 268         /* check if we have the header */
 269         if (    (s->rstate != SSL_ST_READ_BODY) ||
 270                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 271                 {
 272                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 273                 if (n <= 0) return(n); /* error or non-blocking */
 274                 s->rstate=SSL_ST_READ_BODY;
 275
 276                 p=s->packet;
 277
 278                 /* Pull apart the header into the SSL3_RECORD */
 279                 rr->type= *(p++);
 280                 ssl_major= *(p++);
 281                 ssl_minor= *(p++);
 282                 version=(ssl_major<<8)|ssl_minor;
 283                 n2s(p,rr->length);
 284
 285                 /* Lets check version */
 286                 if (!s->first_packet)
 287                         {
 288                         if (version != s->version)
 289                                 {
 290                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 291                                 if ((s->version & 0xFF00) == (version & 0xFF00))
 292                                         /* Send back error using their minor version number :-) */
 293                                         s->version = (unsigned short)version;
 294                                 al=SSL_AD_PROTOCOL_VERSION;
 295                                 goto f_err;
 296                                 }
 297                         }
 298
 299                 if ((version>>8) != SSL3_VERSION_MAJOR)
 300                         {
 301                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 302                         goto err;
 303                         }
 304
 305                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 306                         {
 307                         al=SSL_AD_RECORD_OVERFLOW;
 308                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 309                         goto f_err;
 310                         }
 311
 312                 /* now s->rstate == SSL_ST_READ_BODY */
 313                 }
 314
 315         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 316
 317         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
 318                 {
 319                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
 320                 i=rr->length;
 321                 n=ssl3_read_n(s,i,i,1);
 322                 if (n <= 0) return(n); /* error or non-blocking io */
 323                 /* now n == rr->length,
 324                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
 325                 }
 326
 327         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 328
 329         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 330          * and we have that many bytes in s->packet
 331          */
 332         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 333
 334         /* ok, we can now read from 's->packet' data into 'rr'
 335          * rr->input points at rr->length bytes, which
 336          * need to be copied into rr->data by either
 337          * the decryption or by the decompression
 338          * When the data is 'copied' into the rr->data buffer,
 339          * rr->input will be pointed at the new buffer */
 340
 341         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 342          * rr->length bytes of encrypted compressed stuff. */
 343
 344         /* check is not needed I believe */
 345         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 346                 {
 347                 al=SSL_AD_RECORD_OVERFLOW;
 348                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 349                 goto f_err;
 350                 }
 351
 352         /* decrypt in place in 'rr->input' */
 353         rr->data=rr->input;
 354
 355         enc_err = s->method->ssl3_enc->enc(s,0);
 356         /* enc_err is:
 357          *    0: (in non-constant time) if the record is publically invalid.
 358          *    1: if the padding is valid
 359          *    -1: if the padding is invalid */
 360         if (enc_err == 0)
 361                 {
 362                 al=SSL_AD_DECRYPTION_FAILED;
 363                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
 364                 goto f_err;
 365                 }
 366
 367 #ifdef TLS_DEBUG
 368 printf("dec %d\n",rr->length);
 369 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 370 printf("\n");
 371 #endif
 372
 373         /* r->length is now the compressed data plus mac */
 374         if ((sess != NULL) &&
 375             (s->enc_read_ctx != NULL) &&
 376             (s->read_hash != NULL))
 377                 {
 378                 /* s->read_hash != NULL => mac_size != -1 */
 379                 unsigned char *mac = NULL;
 380                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 381                 mac_size=EVP_MD_size(s->read_hash);
 382                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 383
 384                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 385                 orig_len = rr->length+((unsigned int)rr->type>>8);
 386
 387                 /* orig_len is the length of the record before any padding was
 388                  * removed. This is public information, as is the MAC in use,
 389                  * therefore we can safely process the record in a different
 390                  * amount of time if it's too short to possibly contain a MAC.
 391                  */
 392                 if (orig_len < mac_size ||
 393                     /* CBC records must have a padding length byte too. */
 394                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 395                      orig_len < mac_size+1))
 396                         {
 397                         al=SSL_AD_DECODE_ERROR;
 398                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 399                         goto f_err;
 400                         }
 401
 402                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 403                         {
 404                         /* We update the length so that the TLS header bytes
 405                          * can be constructed correctly but we need to extract
 406                          * the MAC in constant time from within the record,
 407                          * without leaking the contents of the padding bytes.
 408                          * */
 409                         mac = mac_tmp;
 410                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 411                         rr->length -= mac_size;
 412                         }
 413                 else
 414                         {
 415                         /* In this case there's no padding, so |orig_len|
 416                          * equals |rec->length| and we checked that there's
 417                          * enough bytes for |mac_size| above. */
 418                         rr->length -= mac_size;
 419                         mac = &rr->data[rr->length];
 420                         }
 421
 422                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 423                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 424                         enc_err = -1;
 425                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 426                         enc_err = -1;
 427                 }
 428
 429         if (enc_err < 0)
 430                 {
 431                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
 432                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
 433                  * failure is directly visible from the ciphertext anyway,
 434                  * we should not reveal which kind of error occured -- this
 435                  * might become visible to an attacker (e.g. via a logfile) */
 436                 al=SSL_AD_BAD_RECORD_MAC;
 437                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
 438                 goto f_err;
 439                 }
 440
 441         /* r->length is now just compressed */
 442         if (s->expand != NULL)
 443                 {
 444                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 445                         {
 446                         al=SSL_AD_RECORD_OVERFLOW;
 447                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 448                         goto f_err;
 449                         }
 450                 if (!ssl3_do_uncompress(s))
 451                         {
 452                         al=SSL_AD_DECOMPRESSION_FAILURE;
 453                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 454                         goto f_err;
 455                         }
 456                 }
 457
 458         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
 459                 {
 460                 al=SSL_AD_RECORD_OVERFLOW;
 461                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 462                 goto f_err;
 463                 }
 464
 465         rr->off=0;
 466         /* So at this point the following is true
 467          * ssl->s3->rrec.type   is the type of record
 468          * ssl->s3->rrec.length == number of bytes in record
 469          * ssl->s3->rrec.off    == offset to first valid byte
 470          * ssl->s3->rrec.data   == where to take bytes from, increment
 471          *                         after use :-).
 472          */
 473
 474         /* we have pulled in a full packet so zero things */
 475         s->packet_length=0;
 476
 477         /* just read a 0 length packet */
 478         if (rr->length == 0) goto again;
 479
 480         return(1);
 481
 482 f_err:
 483         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 484 err:
 485         return(ret);
 486         }
 487
 488 int ssl3_do_uncompress(SSL *ssl)
 489         {
 490 #ifndef OPENSSL_NO_COMP
 491         int i;
 492         SSL3_RECORD *rr;
 493
 494         rr= &(ssl->s3->rrec);
 495         i=COMP_expand_block(ssl->expand,rr->comp,
 496                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 497         if (i < 0)
 498                 return(0);
 499         else
 500                 rr->length=i;
 501         rr->data=rr->comp;
 502 #endif
 503         return(1);
 504         }
 505
 506 int ssl3_do_compress(SSL *ssl)
 507         {
 508 #ifndef OPENSSL_NO_COMP
 509         int i;
 510         SSL3_RECORD *wr;
 511
 512         wr= &(ssl->s3->wrec);
 513         i=COMP_compress_block(ssl->compress,wr->data,
 514                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 515                 wr->input,(int)wr->length);
 516         if (i < 0)
 517                 return(0);
 518         else
 519                 wr->length=i;
 520
 521         wr->input=wr->data;
 522 #endif
 523         return(1);
 524         }
 525
 526 /* Call this to write data in records of type 'type'
 527  * It will return <= 0 if not all data has been sent or non-blocking IO.
 528  */
 529 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 530         {
 531         const unsigned char *buf=buf_;
 532         unsigned int tot,n,nw;
 533         int i;
 534
 535         s->rwstate=SSL_NOTHING;
 536         tot=s->s3->wnum;
 537         s->s3->wnum=0;
 538
 539         if (SSL_in_init(s) && !s->in_handshake)
 540                 {
 541                 i=s->handshake_func(s);
 542                 if (i < 0) return(i);
 543                 if (i == 0)
 544                         {
 545                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 546                         return -1;
 547                         }
 548                 }
 549
 550         n=(len-tot);
 551         for (;;)
 552                 {
 553                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
 554                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
 555                 else
 556                         nw=n;
 557
 558                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
 559                 if (i <= 0)
 560                         {
 561                         s->s3->wnum=tot;
 562                         return i;
 563                         }
 564
 565                 if ((i == (int)n) ||
 566                         (type == SSL3_RT_APPLICATION_DATA &&
 567                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 568                         {
 569                         /* next chunk of data should get another prepended empty fragment
 570                          * in ciphersuites with known-IV weakness: */
 571                         s->s3->empty_fragment_done = 0;
 572
 573                         return tot+i;
 574                         }
 575
 576                 n-=i;
 577                 tot+=i;
 578                 }
 579         }
 580
 581 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 582                          unsigned int len, int create_empty_fragment)
 583         {
 584         unsigned char *p,*plen;
 585         int i,mac_size,clear=0;
 586         int prefix_len = 0;
 587         SSL3_RECORD *wr;
 588         SSL3_BUFFER *wb;
 589         SSL_SESSION *sess;
 590
 591         /* first check if there is a SSL3_BUFFER still being written
 592          * out.  This will happen with non blocking IO */
 593         if (s->s3->wbuf.left != 0)
 594                 return(ssl3_write_pending(s,type,buf,len));
 595
 596         /* If we have an alert to send, lets send it */
 597         if (s->s3->alert_dispatch)
 598                 {
 599                 i=s->method->ssl_dispatch_alert(s);
 600                 if (i <= 0)
 601                         return(i);
 602                 /* if it went, fall through and send more stuff */
 603                 }
 604
 605         if (len == 0 && !create_empty_fragment)
 606                 return 0;
 607
 608         wr= &(s->s3->wrec);
 609         wb= &(s->s3->wbuf);
 610         sess=s->session;
 611
 612         if (    (sess == NULL) ||
 613                 (s->enc_write_ctx == NULL) ||
 614                 (s->write_hash == NULL))
 615                 clear=1;
 616
 617         if (clear)
 618                 mac_size=0;
 619         else
 620                 mac_size=EVP_MD_size(s->write_hash);
 621
 622         /* 'create_empty_fragment' is true only when this function calls itself */
 623         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
 624                 {
 625                 /* countermeasure against known-IV weakness in CBC ciphersuites
 626                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
 627
 628                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
 629                         {
 630                         /* recursive function call with 'create_empty_fragment' set;
 631                          * this prepares and buffers the data for an empty fragment
 632                          * (these 'prefix_len' bytes are sent out later
 633                          * together with the actual payload) */
 634                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
 635                         if (prefix_len <= 0)
 636                                 goto err;
 637
 638                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
 639                                 {
 640                                 /* insufficient space */
 641                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
 642                                 goto err;
 643                                 }
 644                         }
 645
 646                 s->s3->empty_fragment_done = 1;
 647                 }
 648
 649         p = wb->buf + prefix_len;
 650
 651         /* write the header */
 652
 653         *(p++)=type&0xff;
 654         wr->type=type;
 655
 656         *(p++)=(s->version>>8);
 657         *(p++)=s->version&0xff;
 658
 659         /* field where we are to write out packet length */
 660         plen=p;
 661         p+=2;
 662
 663         /* lets setup the record stuff. */
 664         wr->data=p;
 665         wr->length=(int)len;
 666         wr->input=(unsigned char *)buf;
 667
 668         /* we now 'read' from wr->input, wr->length bytes into
 669          * wr->data */
 670
 671         /* first we compress */
 672         if (s->compress != NULL)
 673                 {
 674                 if (!ssl3_do_compress(s))
 675                         {
 676                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 677                         goto err;
 678                         }
 679                 }
 680         else
 681                 {
 682                 memcpy(wr->data,wr->input,wr->length);
 683                 wr->input=wr->data;
 684                 }
 685
 686         /* we should still have the output to wr->data and the input
 687          * from wr->input.  Length should be wr->length.
 688          * wr->data still points in the wb->buf */
 689
 690         if (mac_size != 0)
 691                 {
 692                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
 693                 wr->length+=mac_size;
 694                 wr->input=p;
 695                 wr->data=p;
 696                 }
 697
 698         /* ssl3_enc can only have an error on read */
 699         s->method->ssl3_enc->enc(s,1);
 700
 701         /* record length after mac and block padding */
 702         s2n(wr->length,plen);
 703
 704         /* we should now have
 705          * wr->data pointing to the encrypted data, which is
 706          * wr->length long */
 707         wr->type=type; /* not needed but helps for debugging */
 708         wr->length+=SSL3_RT_HEADER_LENGTH;
 709
 710         if (create_empty_fragment)
 711                 {
 712                 /* we are in a recursive call;
 713                  * just return the length, don't write out anything here
 714                  */
 715                 return wr->length;
 716                 }
 717
 718         /* now let's set up wb */
 719         wb->left = prefix_len + wr->length;
 720         wb->offset = 0;
 721
 722         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
 723         s->s3->wpend_tot=len;
 724         s->s3->wpend_buf=buf;
 725         s->s3->wpend_type=type;
 726         s->s3->wpend_ret=len;
 727
 728         /* we now just need to write the buffer */
 729         return ssl3_write_pending(s,type,buf,len);
 730 err:
 731         return -1;
 732         }
 733
 734 /* if s->s3->wbuf.left != 0, we need to call this */
 735 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 736         unsigned int len)
 737         {
 738         int i;
 739
 740 /* XXXX */
 741         if ((s->s3->wpend_tot > (int)len)
 742                 || ((s->s3->wpend_buf != buf) &&
 743                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 744                 || (s->s3->wpend_type != type))
 745                 {
 746                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 747                 return(-1);
 748                 }
 749
 750         for (;;)
 751                 {
 752                 clear_sys_error();
 753                 if (s->wbio != NULL)
 754                         {
 755                         s->rwstate=SSL_WRITING;
 756                         i=BIO_write(s->wbio,
 757                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
 758                                 (unsigned int)s->s3->wbuf.left);
 759                         }
 760                 else
 761                         {
 762                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 763                         i= -1;
 764                         }
 765                 if (i == s->s3->wbuf.left)
 766                         {
 767                         s->s3->wbuf.left=0;
 768                         s->rwstate=SSL_NOTHING;
 769                         return(s->s3->wpend_ret);
 770                         }
 771                 else if (i <= 0) {
 772                         if (s->version == DTLS1_VERSION ||
 773                             s->version == DTLS1_BAD_VER) {
 774                                 /* For DTLS, just drop it. That's kind of the whole
 775                                    point in using a datagram service */
 776                                 s->s3->wbuf.left = 0;
 777                         }
 778                         return(i);
 779                 }
 780                 s->s3->wbuf.offset+=i;
 781                 s->s3->wbuf.left-=i;
 782                 }
 783         }
 784
 785 /* Return up to 'len' payload bytes received in 'type' records.
 786  * 'type' is one of the following:
 787  *
 788  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 789  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 790  *   -  0 (during a shutdown, no data has to be returned)
 791  *
 792  * If we don't have stored data to work from, read a SSL/TLS record first
 793  * (possibly multiple records if we still don't have anything to return).
 794  *
 795  * This function must handle any surprises the peer may have for us, such as
 796  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 797  * a surprise, but handled as if it were), or renegotiation requests.
 798  * Also if record payloads contain fragments too small to process, we store
 799  * them until there is enough for the respective protocol (the record protocol
 800  * may use arbitrary fragmentation and even interleaving):
 801  *     Change cipher spec protocol
 802  *             just 1 byte needed, no need for keeping anything stored
 803  *     Alert protocol
 804  *             2 bytes needed (AlertLevel, AlertDescription)
 805  *     Handshake protocol
 806  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 807  *             to detect unexpected Client Hello and Hello Request messages
 808  *             here, anything else is handled by higher layers
 809  *     Application data protocol
 810  *             none of our business
 811  */
 812 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 813         {
 814         int al,i,j,ret;
 815         unsigned int n;
 816         SSL3_RECORD *rr;
 817         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 818
 819         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 820                 if (!ssl3_setup_buffers(s))
 821                         return(-1);
 822
 823         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
 824             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 825                 {
 826                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
 827                 return -1;
 828                 }
 829
 830         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 831                 /* (partially) satisfy request from storage */
 832                 {
 833                 unsigned char *src = s->s3->handshake_fragment;
 834                 unsigned char *dst = buf;
 835                 unsigned int k;
 836
 837                 /* peek == 0 */
 838                 n = 0;
 839                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 840                         {
 841                         *dst++ = *src++;
 842                         len--; s->s3->handshake_fragment_len--;
 843                         n++;
 844                         }
 845                 /* move any remaining fragment bytes: */
 846                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
 847                         s->s3->handshake_fragment[k] = *src++;
 848                 return n;
 849         }
 850
 851         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 852
 853         if (!s->in_handshake && SSL_in_init(s))
 854                 {
 855                 /* type == SSL3_RT_APPLICATION_DATA */
 856                 i=s->handshake_func(s);
 857                 if (i < 0) return(i);
 858                 if (i == 0)
 859                         {
 860                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 861                         return(-1);
 862                         }
 863                 }
 864 start:
 865         s->rwstate=SSL_NOTHING;
 866
 867         /* s->s3->rrec.type         - is the type of record
 868          * s->s3->rrec.data,    - data
 869          * s->s3->rrec.off,     - offset into 'data' for next read
 870          * s->s3->rrec.length,  - number of bytes. */
 871         rr = &(s->s3->rrec);
 872
 873         /* get new packet if necessary */
 874         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 875                 {
 876                 ret=ssl3_get_record(s);
 877                 if (ret <= 0) return(ret);
 878                 }
 879
 880         /* we now have a packet which can be read and processed */
 881
 882         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 883                                        * reset by ssl3_get_finished */
 884                 && (rr->type != SSL3_RT_HANDSHAKE))
 885                 {
 886                 al=SSL_AD_UNEXPECTED_MESSAGE;
 887                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 888                 goto f_err;
 889                 }
 890
 891         /* If the other end has shut down, throw anything we read away
 892          * (even in 'peek' mode) */
 893         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 894                 {
 895                 rr->length=0;
 896                 s->rwstate=SSL_NOTHING;
 897                 return(0);
 898                 }
 899
 900
 901         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 902                 {
 903                 /* make sure that we are not getting application data when we
 904                  * are doing a handshake for the first time */
 905                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 906                         (s->enc_read_ctx == NULL))
 907                         {
 908                         al=SSL_AD_UNEXPECTED_MESSAGE;
 909                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 910                         goto f_err;
 911                         }
 912
 913                 if (len <= 0) return(len);
 914
 915                 if ((unsigned int)len > rr->length)
 916                         n = rr->length;
 917                 else
 918                         n = (unsigned int)len;
 919
 920                 memcpy(buf,&(rr->data[rr->off]),n);
 921                 if (!peek)
 922                         {
 923                         rr->length-=n;
 924                         rr->off+=n;
 925                         if (rr->length == 0)
 926                                 {
 927                                 s->rstate=SSL_ST_READ_HEADER;
 928                                 rr->off=0;
 929                                 }
 930                         }
 931                 return(n);
 932                 }
 933
 934
 935         /* If we get here, then type != rr->type; if we have a handshake
 936          * message, then it was unexpected (Hello Request or Client Hello). */
 937
 938         /* In case of record types for which we have 'fragment' storage,
 939          * fill that so that we can process the data at a fixed place.
 940          */
 941                 {
 942                 unsigned int dest_maxlen = 0;
 943                 unsigned char *dest = NULL;
 944                 unsigned int *dest_len = NULL;
 945
 946                 if (rr->type == SSL3_RT_HANDSHAKE)
 947                         {
 948                         dest_maxlen = sizeof s->s3->handshake_fragment;
 949                         dest = s->s3->handshake_fragment;
 950                         dest_len = &s->s3->handshake_fragment_len;
 951                         }
 952                 else if (rr->type == SSL3_RT_ALERT)
 953                         {
 954                         dest_maxlen = sizeof s->s3->alert_fragment;
 955                         dest = s->s3->alert_fragment;
 956                         dest_len = &s->s3->alert_fragment_len;
 957                         }
 958
 959                 if (dest_maxlen > 0)
 960                         {
 961                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
 962                         if (rr->length < n)
 963                                 n = rr->length; /* available bytes */
 964
 965                         /* now move 'n' bytes: */
 966                         while (n-- > 0)
 967                                 {
 968                                 dest[(*dest_len)++] = rr->data[rr->off++];
 969                                 rr->length--;
 970                                 }
 971
 972                         if (*dest_len < dest_maxlen)
 973                                 goto start; /* fragment was too small */
 974                         }
 975                 }
 976
 977         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
 978          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
 979          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
 980
 981         /* If we are a client, check for an incoming 'Hello Request': */
 982         if ((!s->server) &&
 983                 (s->s3->handshake_fragment_len >= 4) &&
 984                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
 985                 (s->session != NULL) && (s->session->cipher != NULL))
 986                 {
 987                 s->s3->handshake_fragment_len = 0;
 988
 989                 if ((s->s3->handshake_fragment[1] != 0) ||
 990                         (s->s3->handshake_fragment[2] != 0) ||
 991                         (s->s3->handshake_fragment[3] != 0))
 992                         {
 993                         al=SSL_AD_DECODE_ERROR;
 994                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
 995                         goto f_err;
 996                         }
 997
 998                 if (s->msg_callback)
 999                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1000
1001                 if (SSL_is_init_finished(s) &&
1002                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1003                         !s->s3->renegotiate)
1004                         {
1005                         ssl3_renegotiate(s);
1006                         if (ssl3_renegotiate_check(s))
1007                                 {
1008                                 i=s->handshake_func(s);
1009                                 if (i < 0) return(i);
1010                                 if (i == 0)
1011                                         {
1012                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1013                                         return(-1);
1014                                         }
1015
1016                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1017                                         {
1018                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1019                                                 {
1020                                                 BIO *bio;
1021                                                 /* In the case where we try to read application data,
1022                                                  * but we trigger an SSL handshake, we return -1 with
1023                                                  * the retry option set.  Otherwise renegotiation may
1024                                                  * cause nasty problems in the blocking world */
1025                                                 s->rwstate=SSL_READING;
1026                                                 bio=SSL_get_rbio(s);
1027                                                 BIO_clear_retry_flags(bio);
1028                                                 BIO_set_retry_read(bio);
1029                                                 return(-1);
1030                                                 }
1031                                         }
1032                                 }
1033                         }
1034                 /* we either finished a handshake or ignored the request,
1035                  * now try again to obtain the (application) data we were asked for */
1036                 goto start;
1037                 }
1038         /* If we are a server and get a client hello when renegotiation isn't
1039          * allowed send back a no renegotiation alert and carry on.
1040          * WARNING: experimental code, needs reviewing (steve)
1041          */
1042         if (s->server &&
1043                 SSL_is_init_finished(s) &&
1044                 !s->s3->send_connection_binding &&
1045                 (s->version > SSL3_VERSION) &&
1046                 (s->s3->handshake_fragment_len >= 4) &&
1047                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1048                 (s->session != NULL) && (s->session->cipher != NULL) &&
1049                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1050
1051                 {
1052                 /*s->s3->handshake_fragment_len = 0;*/
1053                 rr->length = 0;
1054                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1055                 goto start;
1056                 }
1057         if (s->s3->alert_fragment_len >= 2)
1058                 {
1059                 int alert_level = s->s3->alert_fragment[0];
1060                 int alert_descr = s->s3->alert_fragment[1];
1061
1062                 s->s3->alert_fragment_len = 0;
1063
1064                 if (s->msg_callback)
1065                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1066
1067                 if (s->info_callback != NULL)
1068                         cb=s->info_callback;
1069                 else if (s->ctx->info_callback != NULL)
1070                         cb=s->ctx->info_callback;
1071
1072                 if (cb != NULL)
1073                         {
1074                         j = (alert_level << 8) | alert_descr;
1075                         cb(s, SSL_CB_READ_ALERT, j);
1076                         }
1077
1078                 if (alert_level == 1) /* warning */
1079                         {
1080                         s->s3->warn_alert = alert_descr;
1081                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1082                                 {
1083                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1084                                 return(0);
1085                                 }
1086                         /* This is a warning but we receive it if we requested
1087                          * renegotiation and the peer denied it. Terminate with
1088                          * a fatal alert because if application tried to
1089                          * renegotiatie it presumably had a good reason and
1090                          * expects it to succeed.
1091                          *
1092                          * In future we might have a renegotiation where we
1093                          * don't care if the peer refused it where we carry on.
1094                          */
1095                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1096                                 {
1097                                 al = SSL_AD_HANDSHAKE_FAILURE;
1098                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1099                                 goto f_err;
1100                                 }
1101                         }
1102                 else if (alert_level == 2) /* fatal */
1103                         {
1104                         char tmp[16];
1105
1106                         s->rwstate=SSL_NOTHING;
1107                         s->s3->fatal_alert = alert_descr;
1108                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1109                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1110                         ERR_add_error_data(2,"SSL alert number ",tmp);
1111                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1112                         SSL_CTX_remove_session(s->ctx,s->session);
1113                         return(0);
1114                         }
1115                 else
1116                         {
1117                         al=SSL_AD_ILLEGAL_PARAMETER;
1118                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1119                         goto f_err;
1120                         }
1121
1122                 goto start;
1123                 }
1124
1125         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1126                 {
1127                 s->rwstate=SSL_NOTHING;
1128                 rr->length=0;
1129                 return(0);
1130                 }
1131
1132         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1133                 {
1134                 /* 'Change Cipher Spec' is just a single byte, so we know
1135                  * exactly what the record payload has to look like */
1136                 if (    (rr->length != 1) || (rr->off != 0) ||
1137                         (rr->data[0] != SSL3_MT_CCS))
1138                         {
1139                         al=SSL_AD_ILLEGAL_PARAMETER;
1140                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1141                         goto f_err;
1142                         }
1143
1144                 /* Check we have a cipher to change to */
1145                 if (s->s3->tmp.new_cipher == NULL)
1146                         {
1147                         al=SSL_AD_UNEXPECTED_MESSAGE;
1148                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1149                         goto f_err;
1150                         }
1151
1152                 rr->length=0;
1153
1154                 if (s->msg_callback)
1155                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1156
1157                 s->s3->change_cipher_spec=1;
1158                 if (!ssl3_do_change_cipher_spec(s))
1159                         goto err;
1160                 else
1161                         goto start;
1162                 }
1163
1164         /* Unexpected handshake message (Client Hello, or protocol violation) */
1165         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1166                 {
1167                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1168                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1169                         {
1170 #if 0 /* worked only because C operator preferences are not as expected (and
1171        * because this is not really needed for clients except for detecting
1172        * protocol violations): */
1173                         s->state=SSL_ST_BEFORE|(s->server)
1174                                 ?SSL_ST_ACCEPT
1175                                 :SSL_ST_CONNECT;
1176 #else
1177                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1178 #endif
1179                         s->new_session=1;
1180                         }
1181                 i=s->handshake_func(s);
1182                 if (i < 0) return(i);
1183                 if (i == 0)
1184                         {
1185                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1186                         return(-1);
1187                         }
1188
1189                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1190                         {
1191                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1192                                 {
1193                                 BIO *bio;
1194                                 /* In the case where we try to read application data,
1195                                  * but we trigger an SSL handshake, we return -1 with
1196                                  * the retry option set.  Otherwise renegotiation may
1197                                  * cause nasty problems in the blocking world */
1198                                 s->rwstate=SSL_READING;
1199                                 bio=SSL_get_rbio(s);
1200                                 BIO_clear_retry_flags(bio);
1201                                 BIO_set_retry_read(bio);
1202                                 return(-1);
1203                                 }
1204                         }
1205                 goto start;
1206                 }
1207
1208         switch (rr->type)
1209                 {
1210         default:
1211 #ifndef OPENSSL_NO_TLS
1212                 /* TLS just ignores unknown message types */
1213                 if (s->version == TLS1_VERSION)
1214                         {
1215                         rr->length = 0;
1216                         goto start;
1217                         }
1218 #endif
1219                 al=SSL_AD_UNEXPECTED_MESSAGE;
1220                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1221                 goto f_err;
1222         case SSL3_RT_CHANGE_CIPHER_SPEC:
1223         case SSL3_RT_ALERT:
1224         case SSL3_RT_HANDSHAKE:
1225                 /* we already handled all of these, with the possible exception
1226                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1227                  * should not happen when type != rr->type */
1228                 al=SSL_AD_UNEXPECTED_MESSAGE;
1229                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1230                 goto f_err;
1231         case SSL3_RT_APPLICATION_DATA:
1232                 /* At this point, we were expecting handshake data,
1233                  * but have application data.  If the library was
1234                  * running inside ssl3_read() (i.e. in_read_app_data
1235                  * is set) and it makes sense to read application data
1236                  * at this point (session renegotiation not yet started),
1237                  * we will indulge it.
1238                  */
1239                 if (s->s3->in_read_app_data &&
1240                         (s->s3->total_renegotiations != 0) &&
1241                         ((
1242                                 (s->state & SSL_ST_CONNECT) &&
1243                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1244                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1245                                 ) || (
1246                                         (s->state & SSL_ST_ACCEPT) &&
1247                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1248                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1249                                         )
1250                                 ))
1251                         {
1252                         s->s3->in_read_app_data=2;
1253                         return(-1);
1254                         }
1255                 else
1256                         {
1257                         al=SSL_AD_UNEXPECTED_MESSAGE;
1258                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1259                         goto f_err;
1260                         }
1261                 }
1262         /* not reached */
1263
1264 f_err:
1265         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1266 err:
1267         return(-1);
1268         }
1269
1270 int ssl3_do_change_cipher_spec(SSL *s)
1271         {
1272         int i;
1273         const char *sender;
1274         int slen;
1275
1276         if (s->state & SSL_ST_ACCEPT)
1277                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1278         else
1279                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1280
1281         if (s->s3->tmp.key_block == NULL)
1282                 {
1283                 if (s->session == NULL)
1284                         {
1285                         /* might happen if dtls1_read_bytes() calls this */
1286                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1287                         return (0);
1288                         }
1289
1290                 s->session->cipher=s->s3->tmp.new_cipher;
1291                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1292                 }
1293
1294         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1295                 return(0);
1296
1297         /* we have to record the message digest at
1298          * this point so we can get it before we read
1299          * the finished message */
1300         if (s->state & SSL_ST_CONNECT)
1301                 {
1302                 sender=s->method->ssl3_enc->server_finished_label;
1303                 slen=s->method->ssl3_enc->server_finished_label_len;
1304                 }
1305         else
1306                 {
1307                 sender=s->method->ssl3_enc->client_finished_label;
1308                 slen=s->method->ssl3_enc->client_finished_label_len;
1309                 }
1310
1311         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1312                 &(s->s3->finish_dgst1),
1313                 &(s->s3->finish_dgst2),
1314                 sender,slen,s->s3->tmp.peer_finish_md);
1315
1316         return(1);
1317         }
1318
1319 int ssl3_send_alert(SSL *s, int level, int desc)
1320         {
1321         /* Map tls/ssl alert value to correct one */
1322         desc=s->method->ssl3_enc->alert_value(desc);
1323         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1324                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1325         if (desc < 0) return -1;
1326         /* If a fatal one, remove from cache */
1327         if ((level == 2) && (s->session != NULL))
1328                 SSL_CTX_remove_session(s->ctx,s->session);
1329
1330         s->s3->alert_dispatch=1;
1331         s->s3->send_alert[0]=level;
1332         s->s3->send_alert[1]=desc;
1333         if (s->s3->wbuf.left == 0) /* data still being written out? */
1334                 return s->method->ssl_dispatch_alert(s);
1335         /* else data is still being written out, we will get written
1336          * some time in the future */
1337         return -1;
1338         }
1339
1340 int ssl3_dispatch_alert(SSL *s)
1341         {
1342         int i,j;
1343         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1344
1345         s->s3->alert_dispatch=0;
1346         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1347         if (i <= 0)
1348                 {
1349                 s->s3->alert_dispatch=1;
1350                 }
1351         else
1352                 {
1353                 /* Alert sent to BIO.  If it is important, flush it now.
1354                  * If the message does not get sent due to non-blocking IO,
1355                  * we will not worry too much. */
1356                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1357                         (void)BIO_flush(s->wbio);
1358
1359                 if (s->msg_callback)
1360                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1361
1362                 if (s->info_callback != NULL)
1363                         cb=s->info_callback;
1364                 else if (s->ctx->info_callback != NULL)
1365                         cb=s->ctx->info_callback;
1366
1367                 if (cb != NULL)
1368                         {
1369                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1370                         cb(s,SSL_CB_WRITE_ALERT,j);
1371                         }
1372                 }
1373         return(i);
1374         }