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 n,nw;
 533         int i,tot;
 534
 535         s->rwstate=SSL_NOTHING;
 536         OPENSSL_assert(s->s3->wnum < INT_MAX);
 537         tot=s->s3->wnum;
 538         s->s3->wnum=0;
 539
 540         if (SSL_in_init(s) && !s->in_handshake)
 541                 {
 542                 i=s->handshake_func(s);
 543                 if (i < 0) return(i);
 544                 if (i == 0)
 545                         {
 546                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 547                         return -1;
 548                         }
 549                 }
 550
 551         /* ensure that if we end up with a smaller value of data to write
 552          * out than the the original len from a write which didn't complete
 553          * for non-blocking I/O and also somehow ended up avoiding
 554          * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
 555          * it must never be possible to end up with (len-tot) as a large
 556          * number that will then promptly send beyond the end of the users
 557          * buffer ... so we trap and report the error in a way the user
 558          * will notice
 559          */
 560         if (len < tot)
 561                 {
 562                 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
 563                 return(-1);
 564                 }
 565
 566
 567         n=(len-tot);
 568         for (;;)
 569                 {
 570                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
 571                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
 572                 else
 573                         nw=n;
 574
 575                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
 576                 if (i <= 0)
 577                         {
 578                         s->s3->wnum=tot;
 579                         return i;
 580                         }
 581
 582                 if ((i == (int)n) ||
 583                         (type == SSL3_RT_APPLICATION_DATA &&
 584                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 585                         {
 586                         /* next chunk of data should get another prepended empty fragment
 587                          * in ciphersuites with known-IV weakness: */
 588                         s->s3->empty_fragment_done = 0;
 589
 590                         return tot+i;
 591                         }
 592
 593                 n-=i;
 594                 tot+=i;
 595                 }
 596         }
 597
 598 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 599                          unsigned int len, int create_empty_fragment)
 600         {
 601         unsigned char *p,*plen;
 602         int i,mac_size,clear=0;
 603         int prefix_len = 0;
 604         SSL3_RECORD *wr;
 605         SSL3_BUFFER *wb;
 606         SSL_SESSION *sess;
 607
 608         /* first check if there is a SSL3_BUFFER still being written
 609          * out.  This will happen with non blocking IO */
 610         if (s->s3->wbuf.left != 0)
 611                 return(ssl3_write_pending(s,type,buf,len));
 612
 613         /* If we have an alert to send, lets send it */
 614         if (s->s3->alert_dispatch)
 615                 {
 616                 i=s->method->ssl_dispatch_alert(s);
 617                 if (i <= 0)
 618                         return(i);
 619                 /* if it went, fall through and send more stuff */
 620                 }
 621
 622         if (len == 0 && !create_empty_fragment)
 623                 return 0;
 624
 625         wr= &(s->s3->wrec);
 626         wb= &(s->s3->wbuf);
 627         sess=s->session;
 628
 629         if (    (sess == NULL) ||
 630                 (s->enc_write_ctx == NULL) ||
 631                 (s->write_hash == NULL))
 632                 clear=1;
 633
 634         if (clear)
 635                 mac_size=0;
 636         else
 637                 mac_size=EVP_MD_size(s->write_hash);
 638
 639         /* 'create_empty_fragment' is true only when this function calls itself */
 640         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
 641                 {
 642                 /* countermeasure against known-IV weakness in CBC ciphersuites
 643                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
 644
 645                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
 646                         {
 647                         /* recursive function call with 'create_empty_fragment' set;
 648                          * this prepares and buffers the data for an empty fragment
 649                          * (these 'prefix_len' bytes are sent out later
 650                          * together with the actual payload) */
 651                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
 652                         if (prefix_len <= 0)
 653                                 goto err;
 654
 655                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
 656                                 {
 657                                 /* insufficient space */
 658                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
 659                                 goto err;
 660                                 }
 661                         }
 662
 663                 s->s3->empty_fragment_done = 1;
 664                 }
 665
 666         p = wb->buf + prefix_len;
 667
 668         /* write the header */
 669
 670         *(p++)=type&0xff;
 671         wr->type=type;
 672
 673         *(p++)=(s->version>>8);
 674         *(p++)=s->version&0xff;
 675
 676         /* field where we are to write out packet length */
 677         plen=p;
 678         p+=2;
 679
 680         /* lets setup the record stuff. */
 681         wr->data=p;
 682         wr->length=(int)len;
 683         wr->input=(unsigned char *)buf;
 684
 685         /* we now 'read' from wr->input, wr->length bytes into
 686          * wr->data */
 687
 688         /* first we compress */
 689         if (s->compress != NULL)
 690                 {
 691                 if (!ssl3_do_compress(s))
 692                         {
 693                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 694                         goto err;
 695                         }
 696                 }
 697         else
 698                 {
 699                 memcpy(wr->data,wr->input,wr->length);
 700                 wr->input=wr->data;
 701                 }
 702
 703         /* we should still have the output to wr->data and the input
 704          * from wr->input.  Length should be wr->length.
 705          * wr->data still points in the wb->buf */
 706
 707         if (mac_size != 0)
 708                 {
 709                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
 710                 wr->length+=mac_size;
 711                 wr->input=p;
 712                 wr->data=p;
 713                 }
 714
 715         /* ssl3_enc can only have an error on read */
 716         s->method->ssl3_enc->enc(s,1);
 717
 718         /* record length after mac and block padding */
 719         s2n(wr->length,plen);
 720
 721         /* we should now have
 722          * wr->data pointing to the encrypted data, which is
 723          * wr->length long */
 724         wr->type=type; /* not needed but helps for debugging */
 725         wr->length+=SSL3_RT_HEADER_LENGTH;
 726
 727         if (create_empty_fragment)
 728                 {
 729                 /* we are in a recursive call;
 730                  * just return the length, don't write out anything here
 731                  */
 732                 return wr->length;
 733                 }
 734
 735         /* now let's set up wb */
 736         wb->left = prefix_len + wr->length;
 737         wb->offset = 0;
 738
 739         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
 740         s->s3->wpend_tot=len;
 741         s->s3->wpend_buf=buf;
 742         s->s3->wpend_type=type;
 743         s->s3->wpend_ret=len;
 744
 745         /* we now just need to write the buffer */
 746         return ssl3_write_pending(s,type,buf,len);
 747 err:
 748         return -1;
 749         }
 750
 751 /* if s->s3->wbuf.left != 0, we need to call this */
 752 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 753         unsigned int len)
 754         {
 755         int i;
 756
 757 /* XXXX */
 758         if ((s->s3->wpend_tot > (int)len)
 759                 || ((s->s3->wpend_buf != buf) &&
 760                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 761                 || (s->s3->wpend_type != type))
 762                 {
 763                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 764                 return(-1);
 765                 }
 766
 767         for (;;)
 768                 {
 769                 clear_sys_error();
 770                 if (s->wbio != NULL)
 771                         {
 772                         s->rwstate=SSL_WRITING;
 773                         i=BIO_write(s->wbio,
 774                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
 775                                 (unsigned int)s->s3->wbuf.left);
 776                         }
 777                 else
 778                         {
 779                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 780                         i= -1;
 781                         }
 782                 if (i == s->s3->wbuf.left)
 783                         {
 784                         s->s3->wbuf.left=0;
 785                         s->rwstate=SSL_NOTHING;
 786                         return(s->s3->wpend_ret);
 787                         }
 788                 else if (i <= 0) {
 789                         if (s->version == DTLS1_VERSION ||
 790                             s->version == DTLS1_BAD_VER) {
 791                                 /* For DTLS, just drop it. That's kind of the whole
 792                                    point in using a datagram service */
 793                                 s->s3->wbuf.left = 0;
 794                         }
 795                         return(i);
 796                 }
 797                 s->s3->wbuf.offset+=i;
 798                 s->s3->wbuf.left-=i;
 799                 }
 800         }
 801
 802 /* Return up to 'len' payload bytes received in 'type' records.
 803  * 'type' is one of the following:
 804  *
 805  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 806  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 807  *   -  0 (during a shutdown, no data has to be returned)
 808  *
 809  * If we don't have stored data to work from, read a SSL/TLS record first
 810  * (possibly multiple records if we still don't have anything to return).
 811  *
 812  * This function must handle any surprises the peer may have for us, such as
 813  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 814  * a surprise, but handled as if it were), or renegotiation requests.
 815  * Also if record payloads contain fragments too small to process, we store
 816  * them until there is enough for the respective protocol (the record protocol
 817  * may use arbitrary fragmentation and even interleaving):
 818  *     Change cipher spec protocol
 819  *             just 1 byte needed, no need for keeping anything stored
 820  *     Alert protocol
 821  *             2 bytes needed (AlertLevel, AlertDescription)
 822  *     Handshake protocol
 823  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 824  *             to detect unexpected Client Hello and Hello Request messages
 825  *             here, anything else is handled by higher layers
 826  *     Application data protocol
 827  *             none of our business
 828  */
 829 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 830         {
 831         int al,i,j,ret;
 832         unsigned int n;
 833         SSL3_RECORD *rr;
 834         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 835
 836         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 837                 if (!ssl3_setup_buffers(s))
 838                         return(-1);
 839
 840         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
 841             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 842                 {
 843                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
 844                 return -1;
 845                 }
 846
 847         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 848                 /* (partially) satisfy request from storage */
 849                 {
 850                 unsigned char *src = s->s3->handshake_fragment;
 851                 unsigned char *dst = buf;
 852                 unsigned int k;
 853
 854                 /* peek == 0 */
 855                 n = 0;
 856                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 857                         {
 858                         *dst++ = *src++;
 859                         len--; s->s3->handshake_fragment_len--;
 860                         n++;
 861                         }
 862                 /* move any remaining fragment bytes: */
 863                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
 864                         s->s3->handshake_fragment[k] = *src++;
 865                 return n;
 866         }
 867
 868         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 869
 870         if (!s->in_handshake && SSL_in_init(s))
 871                 {
 872                 /* type == SSL3_RT_APPLICATION_DATA */
 873                 i=s->handshake_func(s);
 874                 if (i < 0) return(i);
 875                 if (i == 0)
 876                         {
 877                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 878                         return(-1);
 879                         }
 880                 }
 881 start:
 882         s->rwstate=SSL_NOTHING;
 883
 884         /* s->s3->rrec.type         - is the type of record
 885          * s->s3->rrec.data,    - data
 886          * s->s3->rrec.off,     - offset into 'data' for next read
 887          * s->s3->rrec.length,  - number of bytes. */
 888         rr = &(s->s3->rrec);
 889
 890         /* get new packet if necessary */
 891         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 892                 {
 893                 ret=ssl3_get_record(s);
 894                 if (ret <= 0) return(ret);
 895                 }
 896
 897         /* we now have a packet which can be read and processed */
 898
 899         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 900                                        * reset by ssl3_get_finished */
 901                 && (rr->type != SSL3_RT_HANDSHAKE))
 902                 {
 903                 al=SSL_AD_UNEXPECTED_MESSAGE;
 904                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 905                 goto f_err;
 906                 }
 907
 908         /* If the other end has shut down, throw anything we read away
 909          * (even in 'peek' mode) */
 910         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 911                 {
 912                 rr->length=0;
 913                 s->rwstate=SSL_NOTHING;
 914                 return(0);
 915                 }
 916
 917
 918         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 919                 {
 920                 /* make sure that we are not getting application data when we
 921                  * are doing a handshake for the first time */
 922                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 923                         (s->enc_read_ctx == NULL))
 924                         {
 925                         al=SSL_AD_UNEXPECTED_MESSAGE;
 926                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 927                         goto f_err;
 928                         }
 929
 930                 if (len <= 0) return(len);
 931
 932                 if ((unsigned int)len > rr->length)
 933                         n = rr->length;
 934                 else
 935                         n = (unsigned int)len;
 936
 937                 memcpy(buf,&(rr->data[rr->off]),n);
 938                 if (!peek)
 939                         {
 940                         rr->length-=n;
 941                         rr->off+=n;
 942                         if (rr->length == 0)
 943                                 {
 944                                 s->rstate=SSL_ST_READ_HEADER;
 945                                 rr->off=0;
 946                                 }
 947                         }
 948                 return(n);
 949                 }
 950
 951
 952         /* If we get here, then type != rr->type; if we have a handshake
 953          * message, then it was unexpected (Hello Request or Client Hello). */
 954
 955         /* In case of record types for which we have 'fragment' storage,
 956          * fill that so that we can process the data at a fixed place.
 957          */
 958                 {
 959                 unsigned int dest_maxlen = 0;
 960                 unsigned char *dest = NULL;
 961                 unsigned int *dest_len = NULL;
 962
 963                 if (rr->type == SSL3_RT_HANDSHAKE)
 964                         {
 965                         dest_maxlen = sizeof s->s3->handshake_fragment;
 966                         dest = s->s3->handshake_fragment;
 967                         dest_len = &s->s3->handshake_fragment_len;
 968                         }
 969                 else if (rr->type == SSL3_RT_ALERT)
 970                         {
 971                         dest_maxlen = sizeof s->s3->alert_fragment;
 972                         dest = s->s3->alert_fragment;
 973                         dest_len = &s->s3->alert_fragment_len;
 974                         }
 975
 976                 if (dest_maxlen > 0)
 977                         {
 978                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
 979                         if (rr->length < n)
 980                                 n = rr->length; /* available bytes */
 981
 982                         /* now move 'n' bytes: */
 983                         while (n-- > 0)
 984                                 {
 985                                 dest[(*dest_len)++] = rr->data[rr->off++];
 986                                 rr->length--;
 987                                 }
 988
 989                         if (*dest_len < dest_maxlen)
 990                                 goto start; /* fragment was too small */
 991                         }
 992                 }
 993
 994         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
 995          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
 996          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
 997
 998         /* If we are a client, check for an incoming 'Hello Request': */
 999         if ((!s->server) &&
1000                 (s->s3->handshake_fragment_len >= 4) &&
1001                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1002                 (s->session != NULL) && (s->session->cipher != NULL))
1003                 {
1004                 s->s3->handshake_fragment_len = 0;
1005
1006                 if ((s->s3->handshake_fragment[1] != 0) ||
1007                         (s->s3->handshake_fragment[2] != 0) ||
1008                         (s->s3->handshake_fragment[3] != 0))
1009                         {
1010                         al=SSL_AD_DECODE_ERROR;
1011                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1012                         goto f_err;
1013                         }
1014
1015                 if (s->msg_callback)
1016                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1017
1018                 if (SSL_is_init_finished(s) &&
1019                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1020                         !s->s3->renegotiate)
1021                         {
1022                         ssl3_renegotiate(s);
1023                         if (ssl3_renegotiate_check(s))
1024                                 {
1025                                 i=s->handshake_func(s);
1026                                 if (i < 0) return(i);
1027                                 if (i == 0)
1028                                         {
1029                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1030                                         return(-1);
1031                                         }
1032
1033                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1034                                         {
1035                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1036                                                 {
1037                                                 BIO *bio;
1038                                                 /* In the case where we try to read application data,
1039                                                  * but we trigger an SSL handshake, we return -1 with
1040                                                  * the retry option set.  Otherwise renegotiation may
1041                                                  * cause nasty problems in the blocking world */
1042                                                 s->rwstate=SSL_READING;
1043                                                 bio=SSL_get_rbio(s);
1044                                                 BIO_clear_retry_flags(bio);
1045                                                 BIO_set_retry_read(bio);
1046                                                 return(-1);
1047                                                 }
1048                                         }
1049                                 }
1050                         }
1051                 /* we either finished a handshake or ignored the request,
1052                  * now try again to obtain the (application) data we were asked for */
1053                 goto start;
1054                 }
1055         /* If we are a server and get a client hello when renegotiation isn't
1056          * allowed send back a no renegotiation alert and carry on.
1057          * WARNING: experimental code, needs reviewing (steve)
1058          */
1059         if (s->server &&
1060                 SSL_is_init_finished(s) &&
1061                 !s->s3->send_connection_binding &&
1062                 (s->version > SSL3_VERSION) &&
1063                 (s->s3->handshake_fragment_len >= 4) &&
1064                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1065                 (s->session != NULL) && (s->session->cipher != NULL) &&
1066                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1067
1068                 {
1069                 /*s->s3->handshake_fragment_len = 0;*/
1070                 rr->length = 0;
1071                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1072                 goto start;
1073                 }
1074         if (s->s3->alert_fragment_len >= 2)
1075                 {
1076                 int alert_level = s->s3->alert_fragment[0];
1077                 int alert_descr = s->s3->alert_fragment[1];
1078
1079                 s->s3->alert_fragment_len = 0;
1080
1081                 if (s->msg_callback)
1082                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1083
1084                 if (s->info_callback != NULL)
1085                         cb=s->info_callback;
1086                 else if (s->ctx->info_callback != NULL)
1087                         cb=s->ctx->info_callback;
1088
1089                 if (cb != NULL)
1090                         {
1091                         j = (alert_level << 8) | alert_descr;
1092                         cb(s, SSL_CB_READ_ALERT, j);
1093                         }
1094
1095                 if (alert_level == 1) /* warning */
1096                         {
1097                         s->s3->warn_alert = alert_descr;
1098                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1099                                 {
1100                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1101                                 return(0);
1102                                 }
1103                         /* This is a warning but we receive it if we requested
1104                          * renegotiation and the peer denied it. Terminate with
1105                          * a fatal alert because if application tried to
1106                          * renegotiatie it presumably had a good reason and
1107                          * expects it to succeed.
1108                          *
1109                          * In future we might have a renegotiation where we
1110                          * don't care if the peer refused it where we carry on.
1111                          */
1112                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1113                                 {
1114                                 al = SSL_AD_HANDSHAKE_FAILURE;
1115                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1116                                 goto f_err;
1117                                 }
1118                         }
1119                 else if (alert_level == 2) /* fatal */
1120                         {
1121                         char tmp[16];
1122
1123                         s->rwstate=SSL_NOTHING;
1124                         s->s3->fatal_alert = alert_descr;
1125                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1126                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1127                         ERR_add_error_data(2,"SSL alert number ",tmp);
1128                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1129                         SSL_CTX_remove_session(s->ctx,s->session);
1130                         return(0);
1131                         }
1132                 else
1133                         {
1134                         al=SSL_AD_ILLEGAL_PARAMETER;
1135                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1136                         goto f_err;
1137                         }
1138
1139                 goto start;
1140                 }
1141
1142         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1143                 {
1144                 s->rwstate=SSL_NOTHING;
1145                 rr->length=0;
1146                 return(0);
1147                 }
1148
1149         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1150                 {
1151                 /* 'Change Cipher Spec' is just a single byte, so we know
1152                  * exactly what the record payload has to look like */
1153                 if (    (rr->length != 1) || (rr->off != 0) ||
1154                         (rr->data[0] != SSL3_MT_CCS))
1155                         {
1156                         al=SSL_AD_ILLEGAL_PARAMETER;
1157                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1158                         goto f_err;
1159                         }
1160
1161                 /* Check we have a cipher to change to */
1162                 if (s->s3->tmp.new_cipher == NULL)
1163                         {
1164                         al=SSL_AD_UNEXPECTED_MESSAGE;
1165                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1166                         goto f_err;
1167                         }
1168
1169                 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1170                         {
1171                         al=SSL_AD_UNEXPECTED_MESSAGE;
1172                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1173                         goto f_err;
1174                         }
1175
1176                 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1177
1178                 rr->length=0;
1179
1180                 if (s->msg_callback)
1181                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1182
1183                 s->s3->change_cipher_spec=1;
1184                 if (!ssl3_do_change_cipher_spec(s))
1185                         goto err;
1186                 else
1187                         goto start;
1188                 }
1189
1190         /* Unexpected handshake message (Client Hello, or protocol violation) */
1191         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1192                 {
1193                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1194                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1195                         {
1196 #if 0 /* worked only because C operator preferences are not as expected (and
1197        * because this is not really needed for clients except for detecting
1198        * protocol violations): */
1199                         s->state=SSL_ST_BEFORE|(s->server)
1200                                 ?SSL_ST_ACCEPT
1201                                 :SSL_ST_CONNECT;
1202 #else
1203                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1204 #endif
1205                         s->new_session=1;
1206                         }
1207                 i=s->handshake_func(s);
1208                 if (i < 0) return(i);
1209                 if (i == 0)
1210                         {
1211                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1212                         return(-1);
1213                         }
1214
1215                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1216                         {
1217                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1218                                 {
1219                                 BIO *bio;
1220                                 /* In the case where we try to read application data,
1221                                  * but we trigger an SSL handshake, we return -1 with
1222                                  * the retry option set.  Otherwise renegotiation may
1223                                  * cause nasty problems in the blocking world */
1224                                 s->rwstate=SSL_READING;
1225                                 bio=SSL_get_rbio(s);
1226                                 BIO_clear_retry_flags(bio);
1227                                 BIO_set_retry_read(bio);
1228                                 return(-1);
1229                                 }
1230                         }
1231                 goto start;
1232                 }
1233
1234         switch (rr->type)
1235                 {
1236         default:
1237 #ifndef OPENSSL_NO_TLS
1238                 /* TLS just ignores unknown message types */
1239                 if (s->version == TLS1_VERSION)
1240                         {
1241                         rr->length = 0;
1242                         goto start;
1243                         }
1244 #endif
1245                 al=SSL_AD_UNEXPECTED_MESSAGE;
1246                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1247                 goto f_err;
1248         case SSL3_RT_CHANGE_CIPHER_SPEC:
1249         case SSL3_RT_ALERT:
1250         case SSL3_RT_HANDSHAKE:
1251                 /* we already handled all of these, with the possible exception
1252                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1253                  * should not happen when type != rr->type */
1254                 al=SSL_AD_UNEXPECTED_MESSAGE;
1255                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1256                 goto f_err;
1257         case SSL3_RT_APPLICATION_DATA:
1258                 /* At this point, we were expecting handshake data,
1259                  * but have application data.  If the library was
1260                  * running inside ssl3_read() (i.e. in_read_app_data
1261                  * is set) and it makes sense to read application data
1262                  * at this point (session renegotiation not yet started),
1263                  * we will indulge it.
1264                  */
1265                 if (s->s3->in_read_app_data &&
1266                         (s->s3->total_renegotiations != 0) &&
1267                         ((
1268                                 (s->state & SSL_ST_CONNECT) &&
1269                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1270                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1271                                 ) || (
1272                                         (s->state & SSL_ST_ACCEPT) &&
1273                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1274                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1275                                         )
1276                                 ))
1277                         {
1278                         s->s3->in_read_app_data=2;
1279                         return(-1);
1280                         }
1281                 else
1282                         {
1283                         al=SSL_AD_UNEXPECTED_MESSAGE;
1284                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1285                         goto f_err;
1286                         }
1287                 }
1288         /* not reached */
1289
1290 f_err:
1291         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1292 err:
1293         return(-1);
1294         }
1295
1296 int ssl3_do_change_cipher_spec(SSL *s)
1297         {
1298         int i;
1299         const char *sender;
1300         int slen;
1301
1302         if (s->state & SSL_ST_ACCEPT)
1303                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1304         else
1305                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1306
1307         if (s->s3->tmp.key_block == NULL)
1308                 {
1309                 if (s->session == NULL)
1310                         {
1311                         /* might happen if dtls1_read_bytes() calls this */
1312                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1313                         return (0);
1314                         }
1315
1316                 s->session->cipher=s->s3->tmp.new_cipher;
1317                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1318                 }
1319
1320         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1321                 return(0);
1322
1323         /* we have to record the message digest at
1324          * this point so we can get it before we read
1325          * the finished message */
1326         if (s->state & SSL_ST_CONNECT)
1327                 {
1328                 sender=s->method->ssl3_enc->server_finished_label;
1329                 slen=s->method->ssl3_enc->server_finished_label_len;
1330                 }
1331         else
1332                 {
1333                 sender=s->method->ssl3_enc->client_finished_label;
1334                 slen=s->method->ssl3_enc->client_finished_label_len;
1335                 }
1336
1337         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1338                 &(s->s3->finish_dgst1),
1339                 &(s->s3->finish_dgst2),
1340                 sender,slen,s->s3->tmp.peer_finish_md);
1341
1342         return(1);
1343         }
1344
1345 int ssl3_send_alert(SSL *s, int level, int desc)
1346         {
1347         /* Map tls/ssl alert value to correct one */
1348         desc=s->method->ssl3_enc->alert_value(desc);
1349         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1350                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1351         if (desc < 0) return -1;
1352         /* If a fatal one, remove from cache */
1353         if ((level == 2) && (s->session != NULL))
1354                 SSL_CTX_remove_session(s->ctx,s->session);
1355
1356         s->s3->alert_dispatch=1;
1357         s->s3->send_alert[0]=level;
1358         s->s3->send_alert[1]=desc;
1359         if (s->s3->wbuf.left == 0) /* data still being written out? */
1360                 return s->method->ssl_dispatch_alert(s);
1361         /* else data is still being written out, we will get written
1362          * some time in the future */
1363         return -1;
1364         }
1365
1366 int ssl3_dispatch_alert(SSL *s)
1367         {
1368         int i,j;
1369         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1370
1371         s->s3->alert_dispatch=0;
1372         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1373         if (i <= 0)
1374                 {
1375                 s->s3->alert_dispatch=1;
1376                 }
1377         else
1378                 {
1379                 /* Alert sent to BIO.  If it is important, flush it now.
1380                  * If the message does not get sent due to non-blocking IO,
1381                  * we will not worry too much. */
1382                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1383                         (void)BIO_flush(s->wbio);
1384
1385                 if (s->msg_callback)
1386                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1387
1388                 if (s->info_callback != NULL)
1389                         cb=s->info_callback;
1390                 else if (s->ctx->info_callback != NULL)
1391                         cb=s->ctx->info_callback;
1392
1393                 if (cb != NULL)
1394                         {
1395                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1396                         cb(s,SSL_CB_WRITE_ALERT,j);
1397                         }
1398                 }
1399         return(i);
1400         }