crypto/openssl/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 <limits.h>
 114 #include <errno.h>
 115 #define USE_SOCKETS
 116 #include "ssl_locl.h"
 117 #include <openssl/evp.h>
 118 #include <openssl/buffer.h>
 119
 120 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 121                          unsigned int len, int create_empty_fragment);
 122 static int ssl3_get_record(SSL *s);
 123
 124 int ssl3_read_n(SSL *s, int n, int max, int extend)
 125         {
 126         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
 127          * packet by another n bytes.
 128          * The packet will be in the sub-array of s->s3->rbuf.buf specified
 129          * by s->packet and s->packet_length.
 130          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
 131          * [plus s->packet_length bytes if extend == 1].)
 132          */
 133         int i,off,newb;
 134
 135         if (!extend)
 136                 {
 137                 /* start with empty packet ... */
 138                 if (s->s3->rbuf.left == 0)
 139                         s->s3->rbuf.offset = 0;
 140                 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
 141                 s->packet_length = 0;
 142                 /* ... now we can act as if 'extend' was set */
 143                 }
 144
 145         /* For DTLS/UDP reads should not span multiple packets
 146          * because the read operation returns the whole packet
 147          * at once (as long as it fits into the buffer). */
 148         if (SSL_version(s) == DTLS1_VERSION)
 149                 {
 150                 if ( s->s3->rbuf.left > 0 && n > s->s3->rbuf.left)
 151                         n = s->s3->rbuf.left;
 152                 }
 153
 154         /* if there is enough in the buffer from a previous read, take some */
 155         if (s->s3->rbuf.left >= (int)n)
 156                 {
 157                 s->packet_length+=n;
 158                 s->s3->rbuf.left-=n;
 159                 s->s3->rbuf.offset+=n;
 160                 return(n);
 161                 }
 162
 163         /* else we need to read more data */
 164         if (!s->read_ahead)
 165                 max=n;
 166
 167         {
 168                 /* avoid buffer overflow */
 169                 int max_max = s->s3->rbuf.len - s->packet_length;
 170                 if (max > max_max)
 171                         max = max_max;
 172         }
 173         if (n > max) /* does not happen */
 174                 {
 175                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 176                 return -1;
 177                 }
 178
 179         off = s->packet_length;
 180         newb = s->s3->rbuf.left;
 181         /* Move any available bytes to front of buffer:
 182          * 'off' bytes already pointed to by 'packet',
 183          * 'newb' extra ones at the end */
 184         if (s->packet != s->s3->rbuf.buf)
 185                 {
 186                 /*  off > 0 */
 187                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
 188                 s->packet = s->s3->rbuf.buf;
 189                 }
 190
 191         while (newb < n)
 192                 {
 193                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
 194                  * to read in more until we have off+n (up to off+max if possible) */
 195
 196                 clear_sys_error();
 197                 if (s->rbio != NULL)
 198                         {
 199                         s->rwstate=SSL_READING;
 200                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
 201                         }
 202                 else
 203                         {
 204                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 205                         i = -1;
 206                         }
 207
 208                 if (i <= 0)
 209                         {
 210                         s->s3->rbuf.left = newb;
 211                         return(i);
 212                         }
 213                 newb+=i;
 214                 /* reads should *never* span multiple packets for DTLS because
 215                  * the underlying transport protocol is message oriented as opposed
 216                  * to byte oriented as in the TLS case. */
 217                 if (SSL_version(s) == DTLS1_VERSION)
 218                         {
 219                         if (n > newb)
 220                                 n = newb; /* makes the while condition false */
 221                         }
 222                 }
 223
 224         /* done reading, now the book-keeping */
 225         s->s3->rbuf.offset = off + n;
 226         s->s3->rbuf.left = newb - n;
 227         s->packet_length += n;
 228         s->rwstate=SSL_NOTHING;
 229         return(n);
 230         }
 231
 232 /* Call this to get a new input record.
 233  * It will return <= 0 if more data is needed, normally due to an error
 234  * or non-blocking IO.
 235  * When it finishes, one packet has been decoded and can be found in
 236  * ssl->s3->rrec.type    - is the type of record
 237  * ssl->s3->rrec.data,   - data
 238  * ssl->s3->rrec.length, - number of bytes
 239  */
 240 /* used only by ssl3_read_bytes */
 241 static int ssl3_get_record(SSL *s)
 242         {
 243         int ssl_major,ssl_minor,al;
 244         int enc_err,n,i,ret= -1;
 245         SSL3_RECORD *rr;
 246         SSL_SESSION *sess;
 247         unsigned char *p;
 248         unsigned char md[EVP_MAX_MD_SIZE];
 249         short version;
 250         unsigned mac_size, orig_len;
 251         size_t extra;
 252
 253         rr= &(s->s3->rrec);
 254         sess=s->session;
 255
 256         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 257                 extra=SSL3_RT_MAX_EXTRA;
 258         else
 259                 extra=0;
 260         if (extra != s->s3->rbuf.len - SSL3_RT_MAX_PACKET_SIZE)
 261                 {
 262                 /* actually likely an application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
 263                  * set after ssl3_setup_buffers() was done */
 264                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
 265                 return -1;
 266                 }
 267
 268 again:
 269         /* check if we have the header */
 270         if (    (s->rstate != SSL_ST_READ_BODY) ||
 271                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 272                 {
 273                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 274                 if (n <= 0) return(n); /* error or non-blocking */
 275                 s->rstate=SSL_ST_READ_BODY;
 276
 277                 p=s->packet;
 278
 279                 /* Pull apart the header into the SSL3_RECORD */
 280                 rr->type= *(p++);
 281                 ssl_major= *(p++);
 282                 ssl_minor= *(p++);
 283                 version=(ssl_major<<8)|ssl_minor;
 284                 n2s(p,rr->length);
 285
 286                 /* Lets check version */
 287                 if (!s->first_packet)
 288                         {
 289                         if (version != s->version)
 290                                 {
 291                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 292                                 if ((s->version & 0xFF00) == (version & 0xFF00))
 293                                         /* Send back error using their minor version number :-) */
 294                                         s->version = (unsigned short)version;
 295                                 al=SSL_AD_PROTOCOL_VERSION;
 296                                 goto f_err;
 297                                 }
 298                         }
 299
 300                 if ((version>>8) != SSL3_VERSION_MAJOR)
 301                         {
 302                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 303                         goto err;
 304                         }
 305
 306                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 307                         {
 308                         al=SSL_AD_RECORD_OVERFLOW;
 309                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 310                         goto f_err;
 311                         }
 312
 313                 /* now s->rstate == SSL_ST_READ_BODY */
 314                 }
 315
 316         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 317
 318         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
 319                 {
 320                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
 321                 i=rr->length;
 322                 n=ssl3_read_n(s,i,i,1);
 323                 if (n <= 0) return(n); /* error or non-blocking io */
 324                 /* now n == rr->length,
 325                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
 326                 }
 327
 328         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 329
 330         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 331          * and we have that many bytes in s->packet
 332          */
 333         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 334
 335         /* ok, we can now read from 's->packet' data into 'rr'
 336          * rr->input points at rr->length bytes, which
 337          * need to be copied into rr->data by either
 338          * the decryption or by the decompression
 339          * When the data is 'copied' into the rr->data buffer,
 340          * rr->input will be pointed at the new buffer */
 341
 342         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 343          * rr->length bytes of encrypted compressed stuff. */
 344
 345         /* check is not needed I believe */
 346         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 347                 {
 348                 al=SSL_AD_RECORD_OVERFLOW;
 349                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 350                 goto f_err;
 351                 }
 352
 353         /* decrypt in place in 'rr->input' */
 354         rr->data=rr->input;
 355
 356         enc_err = s->method->ssl3_enc->enc(s,0);
 357         /* enc_err is:
 358          *    0: (in non-constant time) if the record is publically invalid.
 359          *    1: if the padding is valid
 360          *    -1: if the padding is invalid */
 361         if (enc_err == 0)
 362                 {
 363                 al=SSL_AD_DECRYPTION_FAILED;
 364                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
 365                 goto f_err;
 366                 }
 367
 368 #ifdef TLS_DEBUG
 369 printf("dec %d\n",rr->length);
 370 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 371 printf("\n");
 372 #endif
 373
 374         /* r->length is now the compressed data plus mac */
 375         if ((sess != NULL) &&
 376             (s->enc_read_ctx != NULL) &&
 377             (s->read_hash != NULL))
 378                 {
 379                 /* s->read_hash != NULL => mac_size != -1 */
 380                 unsigned char *mac = NULL;
 381                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 382                 mac_size=EVP_MD_size(s->read_hash);
 383                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 384
 385                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 386                 orig_len = rr->length+((unsigned int)rr->type>>8);
 387
 388                 /* orig_len is the length of the record before any padding was
 389                  * removed. This is public information, as is the MAC in use,
 390                  * therefore we can safely process the record in a different
 391                  * amount of time if it's too short to possibly contain a MAC.
 392                  */
 393                 if (orig_len < mac_size ||
 394                     /* CBC records must have a padding length byte too. */
 395                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 396                      orig_len < mac_size+1))
 397                         {
 398                         al=SSL_AD_DECODE_ERROR;
 399                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 400                         goto f_err;
 401                         }
 402
 403                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 404                         {
 405                         /* We update the length so that the TLS header bytes
 406                          * can be constructed correctly but we need to extract
 407                          * the MAC in constant time from within the record,
 408                          * without leaking the contents of the padding bytes.
 409                          * */
 410                         mac = mac_tmp;
 411                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 412                         rr->length -= mac_size;
 413                         }
 414                 else
 415                         {
 416                         /* In this case there's no padding, so |orig_len|
 417                          * equals |rec->length| and we checked that there's
 418                          * enough bytes for |mac_size| above. */
 419                         rr->length -= mac_size;
 420                         mac = &rr->data[rr->length];
 421                         }
 422
 423                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 424                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 425                         enc_err = -1;
 426                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 427                         enc_err = -1;
 428                 }
 429
 430         if (enc_err < 0)
 431                 {
 432                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
 433                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
 434                  * failure is directly visible from the ciphertext anyway,
 435                  * we should not reveal which kind of error occured -- this
 436                  * might become visible to an attacker (e.g. via a logfile) */
 437                 al=SSL_AD_BAD_RECORD_MAC;
 438                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
 439                 goto f_err;
 440                 }
 441
 442         /* r->length is now just compressed */
 443         if (s->expand != NULL)
 444                 {
 445                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 446                         {
 447                         al=SSL_AD_RECORD_OVERFLOW;
 448                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 449                         goto f_err;
 450                         }
 451                 if (!ssl3_do_uncompress(s))
 452                         {
 453                         al=SSL_AD_DECOMPRESSION_FAILURE;
 454                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 455                         goto f_err;
 456                         }
 457                 }
 458
 459         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
 460                 {
 461                 al=SSL_AD_RECORD_OVERFLOW;
 462                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 463                 goto f_err;
 464                 }
 465
 466         rr->off=0;
 467         /* So at this point the following is true
 468          * ssl->s3->rrec.type   is the type of record
 469          * ssl->s3->rrec.length == number of bytes in record
 470          * ssl->s3->rrec.off    == offset to first valid byte
 471          * ssl->s3->rrec.data   == where to take bytes from, increment
 472          *                         after use :-).
 473          */
 474
 475         /* we have pulled in a full packet so zero things */
 476         s->packet_length=0;
 477
 478         /* just read a 0 length packet */
 479         if (rr->length == 0) goto again;
 480
 481         return(1);
 482
 483 f_err:
 484         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 485 err:
 486         return(ret);
 487         }
 488
 489 int ssl3_do_uncompress(SSL *ssl)
 490         {
 491 #ifndef OPENSSL_NO_COMP
 492         int i;
 493         SSL3_RECORD *rr;
 494
 495         rr= &(ssl->s3->rrec);
 496         i=COMP_expand_block(ssl->expand,rr->comp,
 497                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 498         if (i < 0)
 499                 return(0);
 500         else
 501                 rr->length=i;
 502         rr->data=rr->comp;
 503 #endif
 504         return(1);
 505         }
 506
 507 int ssl3_do_compress(SSL *ssl)
 508         {
 509 #ifndef OPENSSL_NO_COMP
 510         int i;
 511         SSL3_RECORD *wr;
 512
 513         wr= &(ssl->s3->wrec);
 514         i=COMP_compress_block(ssl->compress,wr->data,
 515                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 516                 wr->input,(int)wr->length);
 517         if (i < 0)
 518                 return(0);
 519         else
 520                 wr->length=i;
 521
 522         wr->input=wr->data;
 523 #endif
 524         return(1);
 525         }
 526
 527 /* Call this to write data in records of type 'type'
 528  * It will return <= 0 if not all data has been sent or non-blocking IO.
 529  */
 530 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 531         {
 532         const unsigned char *buf=buf_;
 533         unsigned int n,nw;
 534         int i,tot;
 535
 536         s->rwstate=SSL_NOTHING;
 537         OPENSSL_assert(s->s3->wnum <= INT_MAX);
 538         tot=s->s3->wnum;
 539         s->s3->wnum=0;
 540
 541         if (SSL_in_init(s) && !s->in_handshake)
 542                 {
 543                 i=s->handshake_func(s);
 544                 if (i < 0) return(i);
 545                 if (i == 0)
 546                         {
 547                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 548                         return -1;
 549                         }
 550                 }
 551
 552         /* ensure that if we end up with a smaller value of data to write
 553          * out than the the original len from a write which didn't complete
 554          * for non-blocking I/O and also somehow ended up avoiding
 555          * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
 556          * it must never be possible to end up with (len-tot) as a large
 557          * number that will then promptly send beyond the end of the users
 558          * buffer ... so we trap and report the error in a way the user
 559          * will notice
 560          */
 561         if (len < tot)
 562                 {
 563                 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
 564                 return(-1);
 565                 }
 566
 567
 568         n=(len-tot);
 569         for (;;)
 570                 {
 571                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
 572                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
 573                 else
 574                         nw=n;
 575
 576                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
 577                 if (i <= 0)
 578                         {
 579                         s->s3->wnum=tot;
 580                         return i;
 581                         }
 582
 583                 if ((i == (int)n) ||
 584                         (type == SSL3_RT_APPLICATION_DATA &&
 585                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 586                         {
 587                         /* next chunk of data should get another prepended empty fragment
 588                          * in ciphersuites with known-IV weakness: */
 589                         s->s3->empty_fragment_done = 0;
 590
 591                         return tot+i;
 592                         }
 593
 594                 n-=i;
 595                 tot+=i;
 596                 }
 597         }
 598
 599 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 600                          unsigned int len, int create_empty_fragment)
 601         {
 602         unsigned char *p,*plen;
 603         int i,mac_size,clear=0;
 604         int prefix_len = 0;
 605         SSL3_RECORD *wr;
 606         SSL3_BUFFER *wb;
 607         SSL_SESSION *sess;
 608
 609         /* first check if there is a SSL3_BUFFER still being written
 610          * out.  This will happen with non blocking IO */
 611         if (s->s3->wbuf.left != 0)
 612                 return(ssl3_write_pending(s,type,buf,len));
 613
 614         /* If we have an alert to send, lets send it */
 615         if (s->s3->alert_dispatch)
 616                 {
 617                 i=s->method->ssl_dispatch_alert(s);
 618                 if (i <= 0)
 619                         return(i);
 620                 /* if it went, fall through and send more stuff */
 621                 }
 622
 623         if (len == 0 && !create_empty_fragment)
 624                 return 0;
 625
 626         wr= &(s->s3->wrec);
 627         wb= &(s->s3->wbuf);
 628         sess=s->session;
 629
 630         if (    (sess == NULL) ||
 631                 (s->enc_write_ctx == NULL) ||
 632                 (s->write_hash == NULL))
 633                 clear=1;
 634
 635         if (clear)
 636                 mac_size=0;
 637         else
 638                 mac_size=EVP_MD_size(s->write_hash);
 639
 640         /* 'create_empty_fragment' is true only when this function calls itself */
 641         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
 642                 {
 643                 /* countermeasure against known-IV weakness in CBC ciphersuites
 644                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
 645
 646                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
 647                         {
 648                         /* recursive function call with 'create_empty_fragment' set;
 649                          * this prepares and buffers the data for an empty fragment
 650                          * (these 'prefix_len' bytes are sent out later
 651                          * together with the actual payload) */
 652                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
 653                         if (prefix_len <= 0)
 654                                 goto err;
 655
 656                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
 657                                 {
 658                                 /* insufficient space */
 659                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
 660                                 goto err;
 661                                 }
 662                         }
 663
 664                 s->s3->empty_fragment_done = 1;
 665                 }
 666
 667         p = wb->buf + prefix_len;
 668
 669         /* write the header */
 670
 671         *(p++)=type&0xff;
 672         wr->type=type;
 673
 674         *(p++)=(s->version>>8);
 675         *(p++)=s->version&0xff;
 676
 677         /* field where we are to write out packet length */
 678         plen=p;
 679         p+=2;
 680
 681         /* lets setup the record stuff. */
 682         wr->data=p;
 683         wr->length=(int)len;
 684         wr->input=(unsigned char *)buf;
 685
 686         /* we now 'read' from wr->input, wr->length bytes into
 687          * wr->data */
 688
 689         /* first we compress */
 690         if (s->compress != NULL)
 691                 {
 692                 if (!ssl3_do_compress(s))
 693                         {
 694                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 695                         goto err;
 696                         }
 697                 }
 698         else
 699                 {
 700                 memcpy(wr->data,wr->input,wr->length);
 701                 wr->input=wr->data;
 702                 }
 703
 704         /* we should still have the output to wr->data and the input
 705          * from wr->input.  Length should be wr->length.
 706          * wr->data still points in the wb->buf */
 707
 708         if (mac_size != 0)
 709                 {
 710                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
 711                 wr->length+=mac_size;
 712                 wr->input=p;
 713                 wr->data=p;
 714                 }
 715
 716         /* ssl3_enc can only have an error on read */
 717         s->method->ssl3_enc->enc(s,1);
 718
 719         /* record length after mac and block padding */
 720         s2n(wr->length,plen);
 721
 722         /* we should now have
 723          * wr->data pointing to the encrypted data, which is
 724          * wr->length long */
 725         wr->type=type; /* not needed but helps for debugging */
 726         wr->length+=SSL3_RT_HEADER_LENGTH;
 727
 728         if (create_empty_fragment)
 729                 {
 730                 /* we are in a recursive call;
 731                  * just return the length, don't write out anything here
 732                  */
 733                 return wr->length;
 734                 }
 735
 736         /* now let's set up wb */
 737         wb->left = prefix_len + wr->length;
 738         wb->offset = 0;
 739
 740         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
 741         s->s3->wpend_tot=len;
 742         s->s3->wpend_buf=buf;
 743         s->s3->wpend_type=type;
 744         s->s3->wpend_ret=len;
 745
 746         /* we now just need to write the buffer */
 747         return ssl3_write_pending(s,type,buf,len);
 748 err:
 749         return -1;
 750         }
 751
 752 /* if s->s3->wbuf.left != 0, we need to call this */
 753 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 754         unsigned int len)
 755         {
 756         int i;
 757
 758 /* XXXX */
 759         if ((s->s3->wpend_tot > (int)len)
 760                 || ((s->s3->wpend_buf != buf) &&
 761                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 762                 || (s->s3->wpend_type != type))
 763                 {
 764                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 765                 return(-1);
 766                 }
 767
 768         for (;;)
 769                 {
 770                 clear_sys_error();
 771                 if (s->wbio != NULL)
 772                         {
 773                         s->rwstate=SSL_WRITING;
 774                         i=BIO_write(s->wbio,
 775                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
 776                                 (unsigned int)s->s3->wbuf.left);
 777                         }
 778                 else
 779                         {
 780                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 781                         i= -1;
 782                         }
 783                 if (i == s->s3->wbuf.left)
 784                         {
 785                         s->s3->wbuf.left=0;
 786                         s->rwstate=SSL_NOTHING;
 787                         return(s->s3->wpend_ret);
 788                         }
 789                 else if (i <= 0) {
 790                         if (s->version == DTLS1_VERSION ||
 791                             s->version == DTLS1_BAD_VER) {
 792                                 /* For DTLS, just drop it. That's kind of the whole
 793                                    point in using a datagram service */
 794                                 s->s3->wbuf.left = 0;
 795                         }
 796                         return(i);
 797                 }
 798                 s->s3->wbuf.offset+=i;
 799                 s->s3->wbuf.left-=i;
 800                 }
 801         }
 802
 803 /* Return up to 'len' payload bytes received in 'type' records.
 804  * 'type' is one of the following:
 805  *
 806  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 807  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 808  *   -  0 (during a shutdown, no data has to be returned)
 809  *
 810  * If we don't have stored data to work from, read a SSL/TLS record first
 811  * (possibly multiple records if we still don't have anything to return).
 812  *
 813  * This function must handle any surprises the peer may have for us, such as
 814  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 815  * a surprise, but handled as if it were), or renegotiation requests.
 816  * Also if record payloads contain fragments too small to process, we store
 817  * them until there is enough for the respective protocol (the record protocol
 818  * may use arbitrary fragmentation and even interleaving):
 819  *     Change cipher spec protocol
 820  *             just 1 byte needed, no need for keeping anything stored
 821  *     Alert protocol
 822  *             2 bytes needed (AlertLevel, AlertDescription)
 823  *     Handshake protocol
 824  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 825  *             to detect unexpected Client Hello and Hello Request messages
 826  *             here, anything else is handled by higher layers
 827  *     Application data protocol
 828  *             none of our business
 829  */
 830 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 831         {
 832         int al,i,j,ret;
 833         unsigned int n;
 834         SSL3_RECORD *rr;
 835         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 836
 837         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 838                 if (!ssl3_setup_buffers(s))
 839                         return(-1);
 840
 841         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) ||
 842             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 843                 {
 844                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
 845                 return -1;
 846                 }
 847
 848         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 849                 /* (partially) satisfy request from storage */
 850                 {
 851                 unsigned char *src = s->s3->handshake_fragment;
 852                 unsigned char *dst = buf;
 853                 unsigned int k;
 854
 855                 /* peek == 0 */
 856                 n = 0;
 857                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 858                         {
 859                         *dst++ = *src++;
 860                         len--; s->s3->handshake_fragment_len--;
 861                         n++;
 862                         }
 863                 /* move any remaining fragment bytes: */
 864                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
 865                         s->s3->handshake_fragment[k] = *src++;
 866                 return n;
 867         }
 868
 869         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 870
 871         if (!s->in_handshake && SSL_in_init(s))
 872                 {
 873                 /* type == SSL3_RT_APPLICATION_DATA */
 874                 i=s->handshake_func(s);
 875                 if (i < 0) return(i);
 876                 if (i == 0)
 877                         {
 878                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 879                         return(-1);
 880                         }
 881                 }
 882 start:
 883         s->rwstate=SSL_NOTHING;
 884
 885         /* s->s3->rrec.type         - is the type of record
 886          * s->s3->rrec.data,    - data
 887          * s->s3->rrec.off,     - offset into 'data' for next read
 888          * s->s3->rrec.length,  - number of bytes. */
 889         rr = &(s->s3->rrec);
 890
 891         /* get new packet if necessary */
 892         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 893                 {
 894                 ret=ssl3_get_record(s);
 895                 if (ret <= 0) return(ret);
 896                 }
 897
 898         /* we now have a packet which can be read and processed */
 899
 900         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 901                                        * reset by ssl3_get_finished */
 902                 && (rr->type != SSL3_RT_HANDSHAKE))
 903                 {
 904                 al=SSL_AD_UNEXPECTED_MESSAGE;
 905                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 906                 goto f_err;
 907                 }
 908
 909         /* If the other end has shut down, throw anything we read away
 910          * (even in 'peek' mode) */
 911         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 912                 {
 913                 rr->length=0;
 914                 s->rwstate=SSL_NOTHING;
 915                 return(0);
 916                 }
 917
 918
 919         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 920                 {
 921                 /* make sure that we are not getting application data when we
 922                  * are doing a handshake for the first time */
 923                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 924                         (s->enc_read_ctx == NULL))
 925                         {
 926                         al=SSL_AD_UNEXPECTED_MESSAGE;
 927                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 928                         goto f_err;
 929                         }
 930
 931                 if (len <= 0) return(len);
 932
 933                 if ((unsigned int)len > rr->length)
 934                         n = rr->length;
 935                 else
 936                         n = (unsigned int)len;
 937
 938                 memcpy(buf,&(rr->data[rr->off]),n);
 939                 if (!peek)
 940                         {
 941                         rr->length-=n;
 942                         rr->off+=n;
 943                         if (rr->length == 0)
 944                                 {
 945                                 s->rstate=SSL_ST_READ_HEADER;
 946                                 rr->off=0;
 947                                 }
 948                         }
 949                 return(n);
 950                 }
 951
 952
 953         /* If we get here, then type != rr->type; if we have a handshake
 954          * message, then it was unexpected (Hello Request or Client Hello). */
 955
 956         /* In case of record types for which we have 'fragment' storage,
 957          * fill that so that we can process the data at a fixed place.
 958          */
 959                 {
 960                 unsigned int dest_maxlen = 0;
 961                 unsigned char *dest = NULL;
 962                 unsigned int *dest_len = NULL;
 963
 964                 if (rr->type == SSL3_RT_HANDSHAKE)
 965                         {
 966                         dest_maxlen = sizeof s->s3->handshake_fragment;
 967                         dest = s->s3->handshake_fragment;
 968                         dest_len = &s->s3->handshake_fragment_len;
 969                         }
 970                 else if (rr->type == SSL3_RT_ALERT)
 971                         {
 972                         dest_maxlen = sizeof s->s3->alert_fragment;
 973                         dest = s->s3->alert_fragment;
 974                         dest_len = &s->s3->alert_fragment_len;
 975                         }
 976
 977                 if (dest_maxlen > 0)
 978                         {
 979                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
 980                         if (rr->length < n)
 981                                 n = rr->length; /* available bytes */
 982
 983                         /* now move 'n' bytes: */
 984                         while (n-- > 0)
 985                                 {
 986                                 dest[(*dest_len)++] = rr->data[rr->off++];
 987                                 rr->length--;
 988                                 }
 989
 990                         if (*dest_len < dest_maxlen)
 991                                 goto start; /* fragment was too small */
 992                         }
 993                 }
 994
 995         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
 996          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
 997          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
 998
 999         /* If we are a client, check for an incoming 'Hello Request': */
1000         if ((!s->server) &&
1001                 (s->s3->handshake_fragment_len >= 4) &&
1002                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1003                 (s->session != NULL) && (s->session->cipher != NULL))
1004                 {
1005                 s->s3->handshake_fragment_len = 0;
1006
1007                 if ((s->s3->handshake_fragment[1] != 0) ||
1008                         (s->s3->handshake_fragment[2] != 0) ||
1009                         (s->s3->handshake_fragment[3] != 0))
1010                         {
1011                         al=SSL_AD_DECODE_ERROR;
1012                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1013                         goto f_err;
1014                         }
1015
1016                 if (s->msg_callback)
1017                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1018
1019                 if (SSL_is_init_finished(s) &&
1020                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1021                         !s->s3->renegotiate)
1022                         {
1023                         ssl3_renegotiate(s);
1024                         if (ssl3_renegotiate_check(s))
1025                                 {
1026                                 i=s->handshake_func(s);
1027                                 if (i < 0) return(i);
1028                                 if (i == 0)
1029                                         {
1030                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1031                                         return(-1);
1032                                         }
1033
1034                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1035                                         {
1036                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1037                                                 {
1038                                                 BIO *bio;
1039                                                 /* In the case where we try to read application data,
1040                                                  * but we trigger an SSL handshake, we return -1 with
1041                                                  * the retry option set.  Otherwise renegotiation may
1042                                                  * cause nasty problems in the blocking world */
1043                                                 s->rwstate=SSL_READING;
1044                                                 bio=SSL_get_rbio(s);
1045                                                 BIO_clear_retry_flags(bio);
1046                                                 BIO_set_retry_read(bio);
1047                                                 return(-1);
1048                                                 }
1049                                         }
1050                                 }
1051                         }
1052                 /* we either finished a handshake or ignored the request,
1053                  * now try again to obtain the (application) data we were asked for */
1054                 goto start;
1055                 }
1056         /* If we are a server and get a client hello when renegotiation isn't
1057          * allowed send back a no renegotiation alert and carry on.
1058          * WARNING: experimental code, needs reviewing (steve)
1059          */
1060         if (s->server &&
1061                 SSL_is_init_finished(s) &&
1062                 !s->s3->send_connection_binding &&
1063                 (s->version > SSL3_VERSION) &&
1064                 (s->s3->handshake_fragment_len >= 4) &&
1065                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1066                 (s->session != NULL) && (s->session->cipher != NULL) &&
1067                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1068
1069                 {
1070                 /*s->s3->handshake_fragment_len = 0;*/
1071                 rr->length = 0;
1072                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1073                 goto start;
1074                 }
1075         if (s->s3->alert_fragment_len >= 2)
1076                 {
1077                 int alert_level = s->s3->alert_fragment[0];
1078                 int alert_descr = s->s3->alert_fragment[1];
1079
1080                 s->s3->alert_fragment_len = 0;
1081
1082                 if (s->msg_callback)
1083                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1084
1085                 if (s->info_callback != NULL)
1086                         cb=s->info_callback;
1087                 else if (s->ctx->info_callback != NULL)
1088                         cb=s->ctx->info_callback;
1089
1090                 if (cb != NULL)
1091                         {
1092                         j = (alert_level << 8) | alert_descr;
1093                         cb(s, SSL_CB_READ_ALERT, j);
1094                         }
1095
1096                 if (alert_level == 1) /* warning */
1097                         {
1098                         s->s3->warn_alert = alert_descr;
1099                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1100                                 {
1101                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1102                                 return(0);
1103                                 }
1104                         /* This is a warning but we receive it if we requested
1105                          * renegotiation and the peer denied it. Terminate with
1106                          * a fatal alert because if application tried to
1107                          * renegotiatie it presumably had a good reason and
1108                          * expects it to succeed.
1109                          *
1110                          * In future we might have a renegotiation where we
1111                          * don't care if the peer refused it where we carry on.
1112                          */
1113                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1114                                 {
1115                                 al = SSL_AD_HANDSHAKE_FAILURE;
1116                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1117                                 goto f_err;
1118                                 }
1119                         }
1120                 else if (alert_level == 2) /* fatal */
1121                         {
1122                         char tmp[16];
1123
1124                         s->rwstate=SSL_NOTHING;
1125                         s->s3->fatal_alert = alert_descr;
1126                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1127                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1128                         ERR_add_error_data(2,"SSL alert number ",tmp);
1129                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1130                         SSL_CTX_remove_session(s->ctx,s->session);
1131                         return(0);
1132                         }
1133                 else
1134                         {
1135                         al=SSL_AD_ILLEGAL_PARAMETER;
1136                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1137                         goto f_err;
1138                         }
1139
1140                 goto start;
1141                 }
1142
1143         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1144                 {
1145                 s->rwstate=SSL_NOTHING;
1146                 rr->length=0;
1147                 return(0);
1148                 }
1149
1150         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1151                 {
1152                 /* 'Change Cipher Spec' is just a single byte, so we know
1153                  * exactly what the record payload has to look like */
1154                 if (    (rr->length != 1) || (rr->off != 0) ||
1155                         (rr->data[0] != SSL3_MT_CCS))
1156                         {
1157                         al=SSL_AD_ILLEGAL_PARAMETER;
1158                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1159                         goto f_err;
1160                         }
1161
1162                 /* Check we have a cipher to change to */
1163                 if (s->s3->tmp.new_cipher == NULL)
1164                         {
1165                         al=SSL_AD_UNEXPECTED_MESSAGE;
1166                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1167                         goto f_err;
1168                         }
1169
1170                 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1171                         {
1172                         al=SSL_AD_UNEXPECTED_MESSAGE;
1173                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1174                         goto f_err;
1175                         }
1176
1177                 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1178
1179                 rr->length=0;
1180
1181                 if (s->msg_callback)
1182                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1183
1184                 s->s3->change_cipher_spec=1;
1185                 if (!ssl3_do_change_cipher_spec(s))
1186                         goto err;
1187                 else
1188                         goto start;
1189                 }
1190
1191         /* Unexpected handshake message (Client Hello, or protocol violation) */
1192         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1193                 {
1194                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1195                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1196                         {
1197 #if 0 /* worked only because C operator preferences are not as expected (and
1198        * because this is not really needed for clients except for detecting
1199        * protocol violations): */
1200                         s->state=SSL_ST_BEFORE|(s->server)
1201                                 ?SSL_ST_ACCEPT
1202                                 :SSL_ST_CONNECT;
1203 #else
1204                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1205 #endif
1206                         s->new_session=1;
1207                         }
1208                 i=s->handshake_func(s);
1209                 if (i < 0) return(i);
1210                 if (i == 0)
1211                         {
1212                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1213                         return(-1);
1214                         }
1215
1216                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1217                         {
1218                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1219                                 {
1220                                 BIO *bio;
1221                                 /* In the case where we try to read application data,
1222                                  * but we trigger an SSL handshake, we return -1 with
1223                                  * the retry option set.  Otherwise renegotiation may
1224                                  * cause nasty problems in the blocking world */
1225                                 s->rwstate=SSL_READING;
1226                                 bio=SSL_get_rbio(s);
1227                                 BIO_clear_retry_flags(bio);
1228                                 BIO_set_retry_read(bio);
1229                                 return(-1);
1230                                 }
1231                         }
1232                 goto start;
1233                 }
1234
1235         switch (rr->type)
1236                 {
1237         default:
1238 #ifndef OPENSSL_NO_TLS
1239                 /* TLS just ignores unknown message types */
1240                 if (s->version == TLS1_VERSION)
1241                         {
1242                         rr->length = 0;
1243                         goto start;
1244                         }
1245 #endif
1246                 al=SSL_AD_UNEXPECTED_MESSAGE;
1247                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1248                 goto f_err;
1249         case SSL3_RT_CHANGE_CIPHER_SPEC:
1250         case SSL3_RT_ALERT:
1251         case SSL3_RT_HANDSHAKE:
1252                 /* we already handled all of these, with the possible exception
1253                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1254                  * should not happen when type != rr->type */
1255                 al=SSL_AD_UNEXPECTED_MESSAGE;
1256                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1257                 goto f_err;
1258         case SSL3_RT_APPLICATION_DATA:
1259                 /* At this point, we were expecting handshake data,
1260                  * but have application data.  If the library was
1261                  * running inside ssl3_read() (i.e. in_read_app_data
1262                  * is set) and it makes sense to read application data
1263                  * at this point (session renegotiation not yet started),
1264                  * we will indulge it.
1265                  */
1266                 if (s->s3->in_read_app_data &&
1267                         (s->s3->total_renegotiations != 0) &&
1268                         ((
1269                                 (s->state & SSL_ST_CONNECT) &&
1270                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1271                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1272                                 ) || (
1273                                         (s->state & SSL_ST_ACCEPT) &&
1274                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1275                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1276                                         )
1277                                 ))
1278                         {
1279                         s->s3->in_read_app_data=2;
1280                         return(-1);
1281                         }
1282                 else
1283                         {
1284                         al=SSL_AD_UNEXPECTED_MESSAGE;
1285                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1286                         goto f_err;
1287                         }
1288                 }
1289         /* not reached */
1290
1291 f_err:
1292         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1293 err:
1294         return(-1);
1295         }
1296
1297 int ssl3_do_change_cipher_spec(SSL *s)
1298         {
1299         int i;
1300         const char *sender;
1301         int slen;
1302
1303         if (s->state & SSL_ST_ACCEPT)
1304                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1305         else
1306                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1307
1308         if (s->s3->tmp.key_block == NULL)
1309                 {
1310                 if (s->session == NULL || s->session->master_key_length == 0)
1311                         {
1312                         /* might happen if dtls1_read_bytes() calls this */
1313                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1314                         return (0);
1315                         }
1316
1317                 s->session->cipher=s->s3->tmp.new_cipher;
1318                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1319                 }
1320
1321         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1322                 return(0);
1323
1324         /* we have to record the message digest at
1325          * this point so we can get it before we read
1326          * the finished message */
1327         if (s->state & SSL_ST_CONNECT)
1328                 {
1329                 sender=s->method->ssl3_enc->server_finished_label;
1330                 slen=s->method->ssl3_enc->server_finished_label_len;
1331                 }
1332         else
1333                 {
1334                 sender=s->method->ssl3_enc->client_finished_label;
1335                 slen=s->method->ssl3_enc->client_finished_label_len;
1336                 }
1337
1338         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1339                 &(s->s3->finish_dgst1),
1340                 &(s->s3->finish_dgst2),
1341                 sender,slen,s->s3->tmp.peer_finish_md);
1342
1343         return(1);
1344         }
1345
1346 int ssl3_send_alert(SSL *s, int level, int desc)
1347         {
1348         /* Map tls/ssl alert value to correct one */
1349         desc=s->method->ssl3_enc->alert_value(desc);
1350         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1351                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1352         if (desc < 0) return -1;
1353         /* If a fatal one, remove from cache */
1354         if ((level == 2) && (s->session != NULL))
1355                 SSL_CTX_remove_session(s->ctx,s->session);
1356
1357         s->s3->alert_dispatch=1;
1358         s->s3->send_alert[0]=level;
1359         s->s3->send_alert[1]=desc;
1360         if (s->s3->wbuf.left == 0) /* data still being written out? */
1361                 return s->method->ssl_dispatch_alert(s);
1362         /* else data is still being written out, we will get written
1363          * some time in the future */
1364         return -1;
1365         }
1366
1367 int ssl3_dispatch_alert(SSL *s)
1368         {
1369         int i,j;
1370         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1371
1372         s->s3->alert_dispatch=0;
1373         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1374         if (i <= 0)
1375                 {
1376                 s->s3->alert_dispatch=1;
1377                 }
1378         else
1379                 {
1380                 /* Alert sent to BIO.  If it is important, flush it now.
1381                  * If the message does not get sent due to non-blocking IO,
1382                  * we will not worry too much. */
1383                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1384                         (void)BIO_flush(s->wbio);
1385
1386                 if (s->msg_callback)
1387                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1388
1389                 if (s->info_callback != NULL)
1390                         cb=s->info_callback;
1391                 else if (s->ctx->info_callback != NULL)
1392                         cb=s->ctx->info_callback;
1393
1394                 if (cb != NULL)
1395                         {
1396                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1397                         cb(s,SSL_CB_WRITE_ALERT,j);
1398                         }
1399                 }
1400         return(i);
1401         }