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 && extend)
 151                         return 0;
 152                 if ( s->s3->rbuf.left > 0 && n > s->s3->rbuf.left)
 153                         n = s->s3->rbuf.left;
 154                 }
 155
 156         /* if there is enough in the buffer from a previous read, take some */
 157         if (s->s3->rbuf.left >= (int)n)
 158                 {
 159                 s->packet_length+=n;
 160                 s->s3->rbuf.left-=n;
 161                 s->s3->rbuf.offset+=n;
 162                 return(n);
 163                 }
 164
 165         /* else we need to read more data */
 166         if (!s->read_ahead)
 167                 max=n;
 168
 169         {
 170                 /* avoid buffer overflow */
 171                 int max_max = s->s3->rbuf.len - s->packet_length;
 172                 if (max > max_max)
 173                         max = max_max;
 174         }
 175         if (n > max) /* does not happen */
 176                 {
 177                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 178                 return -1;
 179                 }
 180
 181         off = s->packet_length;
 182         newb = s->s3->rbuf.left;
 183         /* Move any available bytes to front of buffer:
 184          * 'off' bytes already pointed to by 'packet',
 185          * 'newb' extra ones at the end */
 186         if (s->packet != s->s3->rbuf.buf)
 187                 {
 188                 /*  off > 0 */
 189                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
 190                 s->packet = s->s3->rbuf.buf;
 191                 }
 192
 193         while (newb < n)
 194                 {
 195                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
 196                  * to read in more until we have off+n (up to off+max if possible) */
 197
 198                 clear_sys_error();
 199                 if (s->rbio != NULL)
 200                         {
 201                         s->rwstate=SSL_READING;
 202                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
 203                         }
 204                 else
 205                         {
 206                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 207                         i = -1;
 208                         }
 209
 210                 if (i <= 0)
 211                         {
 212                         s->s3->rbuf.left = newb;
 213                         return(i);
 214                         }
 215                 newb+=i;
 216                 /* reads should *never* span multiple packets for DTLS because
 217                  * the underlying transport protocol is message oriented as opposed
 218                  * to byte oriented as in the TLS case. */
 219                 if (SSL_version(s) == DTLS1_VERSION)
 220                         {
 221                         if (n > newb)
 222                                 n = newb; /* makes the while condition false */
 223                         }
 224                 }
 225
 226         /* done reading, now the book-keeping */
 227         s->s3->rbuf.offset = off + n;
 228         s->s3->rbuf.left = newb - n;
 229         s->packet_length += n;
 230         s->rwstate=SSL_NOTHING;
 231         return(n);
 232         }
 233
 234 /* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will
 235  * be processed per call to ssl3_get_record. Without this limit an attacker
 236  * could send empty records at a faster rate than we can process and cause
 237  * ssl3_get_record to loop forever. */
 238 #define MAX_EMPTY_RECORDS 32
 239
 240 /* Call this to get a new input record.
 241  * It will return <= 0 if more data is needed, normally due to an error
 242  * or non-blocking IO.
 243  * When it finishes, one packet has been decoded and can be found in
 244  * ssl->s3->rrec.type    - is the type of record
 245  * ssl->s3->rrec.data,   - data
 246  * ssl->s3->rrec.length, - number of bytes
 247  */
 248 /* used only by ssl3_read_bytes */
 249 static int ssl3_get_record(SSL *s)
 250         {
 251         int ssl_major,ssl_minor,al;
 252         int enc_err,n,i,ret= -1;
 253         SSL3_RECORD *rr;
 254         SSL_SESSION *sess;
 255         unsigned char *p;
 256         unsigned char md[EVP_MAX_MD_SIZE];
 257         short version;
 258         unsigned mac_size, orig_len;
 259         size_t extra;
 260         unsigned empty_record_count = 0;
 261
 262         rr= &(s->s3->rrec);
 263         sess=s->session;
 264
 265         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 266                 extra=SSL3_RT_MAX_EXTRA;
 267         else
 268                 extra=0;
 269         if (extra != s->s3->rbuf.len - SSL3_RT_MAX_PACKET_SIZE)
 270                 {
 271                 /* actually likely an application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
 272                  * set after ssl3_setup_buffers() was done */
 273                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
 274                 return -1;
 275                 }
 276
 277 again:
 278         /* check if we have the header */
 279         if (    (s->rstate != SSL_ST_READ_BODY) ||
 280                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 281                 {
 282                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 283                 if (n <= 0) return(n); /* error or non-blocking */
 284                 s->rstate=SSL_ST_READ_BODY;
 285
 286                 p=s->packet;
 287
 288                 /* Pull apart the header into the SSL3_RECORD */
 289                 rr->type= *(p++);
 290                 ssl_major= *(p++);
 291                 ssl_minor= *(p++);
 292                 version=(ssl_major<<8)|ssl_minor;
 293                 n2s(p,rr->length);
 294
 295                 /* Lets check version */
 296                 if (!s->first_packet)
 297                         {
 298                         if (version != s->version)
 299                                 {
 300                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 301                                 if ((s->version & 0xFF00) == (version & 0xFF00))
 302                                         /* Send back error using their minor version number :-) */
 303                                         s->version = (unsigned short)version;
 304                                 al=SSL_AD_PROTOCOL_VERSION;
 305                                 goto f_err;
 306                                 }
 307                         }
 308
 309                 if ((version>>8) != SSL3_VERSION_MAJOR)
 310                         {
 311                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 312                         goto err;
 313                         }
 314
 315                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 316                         {
 317                         al=SSL_AD_RECORD_OVERFLOW;
 318                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 319                         goto f_err;
 320                         }
 321
 322                 /* now s->rstate == SSL_ST_READ_BODY */
 323                 }
 324
 325         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 326
 327         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
 328                 {
 329                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
 330                 i=rr->length;
 331                 n=ssl3_read_n(s,i,i,1);
 332                 if (n <= 0) return(n); /* error or non-blocking io */
 333                 /* now n == rr->length,
 334                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
 335                 }
 336
 337         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 338
 339         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 340          * and we have that many bytes in s->packet
 341          */
 342         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 343
 344         /* ok, we can now read from 's->packet' data into 'rr'
 345          * rr->input points at rr->length bytes, which
 346          * need to be copied into rr->data by either
 347          * the decryption or by the decompression
 348          * When the data is 'copied' into the rr->data buffer,
 349          * rr->input will be pointed at the new buffer */
 350
 351         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 352          * rr->length bytes of encrypted compressed stuff. */
 353
 354         /* check is not needed I believe */
 355         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 356                 {
 357                 al=SSL_AD_RECORD_OVERFLOW;
 358                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 359                 goto f_err;
 360                 }
 361
 362         /* decrypt in place in 'rr->input' */
 363         rr->data=rr->input;
 364
 365         enc_err = s->method->ssl3_enc->enc(s,0);
 366         /* enc_err is:
 367          *    0: (in non-constant time) if the record is publically invalid.
 368          *    1: if the padding is valid
 369          *    -1: if the padding is invalid */
 370         if (enc_err == 0)
 371                 {
 372                 al=SSL_AD_DECRYPTION_FAILED;
 373                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
 374                 goto f_err;
 375                 }
 376
 377 #ifdef TLS_DEBUG
 378 printf("dec %d\n",rr->length);
 379 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 380 printf("\n");
 381 #endif
 382
 383         /* r->length is now the compressed data plus mac */
 384         if ((sess != NULL) &&
 385             (s->enc_read_ctx != NULL) &&
 386             (s->read_hash != NULL))
 387                 {
 388                 /* s->read_hash != NULL => mac_size != -1 */
 389                 unsigned char *mac = NULL;
 390                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 391                 mac_size=EVP_MD_size(s->read_hash);
 392                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 393
 394                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 395                 orig_len = rr->length+((unsigned int)rr->type>>8);
 396
 397                 /* orig_len is the length of the record before any padding was
 398                  * removed. This is public information, as is the MAC in use,
 399                  * therefore we can safely process the record in a different
 400                  * amount of time if it's too short to possibly contain a MAC.
 401                  */
 402                 if (orig_len < mac_size ||
 403                     /* CBC records must have a padding length byte too. */
 404                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 405                      orig_len < mac_size+1))
 406                         {
 407                         al=SSL_AD_DECODE_ERROR;
 408                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 409                         goto f_err;
 410                         }
 411
 412                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 413                         {
 414                         /* We update the length so that the TLS header bytes
 415                          * can be constructed correctly but we need to extract
 416                          * the MAC in constant time from within the record,
 417                          * without leaking the contents of the padding bytes.
 418                          * */
 419                         mac = mac_tmp;
 420                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 421                         rr->length -= mac_size;
 422                         }
 423                 else
 424                         {
 425                         /* In this case there's no padding, so |orig_len|
 426                          * equals |rec->length| and we checked that there's
 427                          * enough bytes for |mac_size| above. */
 428                         rr->length -= mac_size;
 429                         mac = &rr->data[rr->length];
 430                         }
 431
 432                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 433                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 434                         enc_err = -1;
 435                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 436                         enc_err = -1;
 437                 }
 438
 439         if (enc_err < 0)
 440                 {
 441                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
 442                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
 443                  * failure is directly visible from the ciphertext anyway,
 444                  * we should not reveal which kind of error occured -- this
 445                  * might become visible to an attacker (e.g. via a logfile) */
 446                 al=SSL_AD_BAD_RECORD_MAC;
 447                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
 448                 goto f_err;
 449                 }
 450
 451         /* r->length is now just compressed */
 452         if (s->expand != NULL)
 453                 {
 454                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 455                         {
 456                         al=SSL_AD_RECORD_OVERFLOW;
 457                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 458                         goto f_err;
 459                         }
 460                 if (!ssl3_do_uncompress(s))
 461                         {
 462                         al=SSL_AD_DECOMPRESSION_FAILURE;
 463                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 464                         goto f_err;
 465                         }
 466                 }
 467
 468         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
 469                 {
 470                 al=SSL_AD_RECORD_OVERFLOW;
 471                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 472                 goto f_err;
 473                 }
 474
 475         rr->off=0;
 476         /* So at this point the following is true
 477          * ssl->s3->rrec.type   is the type of record
 478          * ssl->s3->rrec.length == number of bytes in record
 479          * ssl->s3->rrec.off    == offset to first valid byte
 480          * ssl->s3->rrec.data   == where to take bytes from, increment
 481          *                         after use :-).
 482          */
 483
 484         /* we have pulled in a full packet so zero things */
 485         s->packet_length=0;
 486
 487         /* just read a 0 length packet */
 488         if (rr->length == 0)
 489                 {
 490                 empty_record_count++;
 491                 if (empty_record_count > MAX_EMPTY_RECORDS)
 492                         {
 493                         al=SSL_AD_UNEXPECTED_MESSAGE;
 494                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL);
 495                         goto f_err;
 496                         }
 497                 goto again;
 498                 }
 499
 500         return(1);
 501
 502 f_err:
 503         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 504 err:
 505         return(ret);
 506         }
 507
 508 int ssl3_do_uncompress(SSL *ssl)
 509         {
 510 #ifndef OPENSSL_NO_COMP
 511         int i;
 512         SSL3_RECORD *rr;
 513
 514         rr= &(ssl->s3->rrec);
 515         i=COMP_expand_block(ssl->expand,rr->comp,
 516                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 517         if (i < 0)
 518                 return(0);
 519         else
 520                 rr->length=i;
 521         rr->data=rr->comp;
 522 #endif
 523         return(1);
 524         }
 525
 526 int ssl3_do_compress(SSL *ssl)
 527         {
 528 #ifndef OPENSSL_NO_COMP
 529         int i;
 530         SSL3_RECORD *wr;
 531
 532         wr= &(ssl->s3->wrec);
 533         i=COMP_compress_block(ssl->compress,wr->data,
 534                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 535                 wr->input,(int)wr->length);
 536         if (i < 0)
 537                 return(0);
 538         else
 539                 wr->length=i;
 540
 541         wr->input=wr->data;
 542 #endif
 543         return(1);
 544         }
 545
 546 /* Call this to write data in records of type 'type'
 547  * It will return <= 0 if not all data has been sent or non-blocking IO.
 548  */
 549 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 550         {
 551         const unsigned char *buf=buf_;
 552         unsigned int n,nw;
 553         int i,tot;
 554
 555         s->rwstate=SSL_NOTHING;
 556         OPENSSL_assert(s->s3->wnum <= INT_MAX);
 557         tot=s->s3->wnum;
 558         s->s3->wnum=0;
 559
 560         if (SSL_in_init(s) && !s->in_handshake)
 561                 {
 562                 i=s->handshake_func(s);
 563                 if (i < 0) return(i);
 564                 if (i == 0)
 565                         {
 566                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 567                         return -1;
 568                         }
 569                 }
 570
 571         /* ensure that if we end up with a smaller value of data to write
 572          * out than the the original len from a write which didn't complete
 573          * for non-blocking I/O and also somehow ended up avoiding
 574          * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
 575          * it must never be possible to end up with (len-tot) as a large
 576          * number that will then promptly send beyond the end of the users
 577          * buffer ... so we trap and report the error in a way the user
 578          * will notice
 579          */
 580         if (len < tot)
 581                 {
 582                 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
 583                 return(-1);
 584                 }
 585
 586
 587         n=(len-tot);
 588         for (;;)
 589                 {
 590                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
 591                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
 592                 else
 593                         nw=n;
 594
 595                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
 596                 if (i <= 0)
 597                         {
 598                         s->s3->wnum=tot;
 599                         return i;
 600                         }
 601
 602                 if ((i == (int)n) ||
 603                         (type == SSL3_RT_APPLICATION_DATA &&
 604                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 605                         {
 606                         /* next chunk of data should get another prepended empty fragment
 607                          * in ciphersuites with known-IV weakness: */
 608                         s->s3->empty_fragment_done = 0;
 609
 610                         return tot+i;
 611                         }
 612
 613                 n-=i;
 614                 tot+=i;
 615                 }
 616         }
 617
 618 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 619                          unsigned int len, int create_empty_fragment)
 620         {
 621         unsigned char *p,*plen;
 622         int i,mac_size,clear=0;
 623         int prefix_len = 0;
 624         SSL3_RECORD *wr;
 625         SSL3_BUFFER *wb;
 626         SSL_SESSION *sess;
 627
 628         /* first check if there is a SSL3_BUFFER still being written
 629          * out.  This will happen with non blocking IO */
 630         if (s->s3->wbuf.left != 0)
 631                 return(ssl3_write_pending(s,type,buf,len));
 632
 633         /* If we have an alert to send, lets send it */
 634         if (s->s3->alert_dispatch)
 635                 {
 636                 i=s->method->ssl_dispatch_alert(s);
 637                 if (i <= 0)
 638                         return(i);
 639                 /* if it went, fall through and send more stuff */
 640                 }
 641
 642         if (len == 0 && !create_empty_fragment)
 643                 return 0;
 644
 645         wr= &(s->s3->wrec);
 646         wb= &(s->s3->wbuf);
 647         sess=s->session;
 648
 649         if (    (sess == NULL) ||
 650                 (s->enc_write_ctx == NULL) ||
 651                 (s->write_hash == NULL))
 652                 clear=1;
 653
 654         if (clear)
 655                 mac_size=0;
 656         else
 657                 mac_size=EVP_MD_size(s->write_hash);
 658
 659         /* 'create_empty_fragment' is true only when this function calls itself */
 660         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
 661                 {
 662                 /* countermeasure against known-IV weakness in CBC ciphersuites
 663                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
 664
 665                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
 666                         {
 667                         /* recursive function call with 'create_empty_fragment' set;
 668                          * this prepares and buffers the data for an empty fragment
 669                          * (these 'prefix_len' bytes are sent out later
 670                          * together with the actual payload) */
 671                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
 672                         if (prefix_len <= 0)
 673                                 goto err;
 674
 675                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
 676                                 {
 677                                 /* insufficient space */
 678                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
 679                                 goto err;
 680                                 }
 681                         }
 682
 683                 s->s3->empty_fragment_done = 1;
 684                 }
 685
 686         p = wb->buf + prefix_len;
 687
 688         /* write the header */
 689
 690         *(p++)=type&0xff;
 691         wr->type=type;
 692
 693         *(p++)=(s->version>>8);
 694         *(p++)=s->version&0xff;
 695
 696         /* field where we are to write out packet length */
 697         plen=p;
 698         p+=2;
 699
 700         /* lets setup the record stuff. */
 701         wr->data=p;
 702         wr->length=(int)len;
 703         wr->input=(unsigned char *)buf;
 704
 705         /* we now 'read' from wr->input, wr->length bytes into
 706          * wr->data */
 707
 708         /* first we compress */
 709         if (s->compress != NULL)
 710                 {
 711                 if (!ssl3_do_compress(s))
 712                         {
 713                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 714                         goto err;
 715                         }
 716                 }
 717         else
 718                 {
 719                 memcpy(wr->data,wr->input,wr->length);
 720                 wr->input=wr->data;
 721                 }
 722
 723         /* we should still have the output to wr->data and the input
 724          * from wr->input.  Length should be wr->length.
 725          * wr->data still points in the wb->buf */
 726
 727         if (mac_size != 0)
 728                 {
 729                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
 730                 wr->length+=mac_size;
 731                 wr->input=p;
 732                 wr->data=p;
 733                 }
 734
 735         /* ssl3_enc can only have an error on read */
 736         s->method->ssl3_enc->enc(s,1);
 737
 738         /* record length after mac and block padding */
 739         s2n(wr->length,plen);
 740
 741         /* we should now have
 742          * wr->data pointing to the encrypted data, which is
 743          * wr->length long */
 744         wr->type=type; /* not needed but helps for debugging */
 745         wr->length+=SSL3_RT_HEADER_LENGTH;
 746
 747         if (create_empty_fragment)
 748                 {
 749                 /* we are in a recursive call;
 750                  * just return the length, don't write out anything here
 751                  */
 752                 return wr->length;
 753                 }
 754
 755         /* now let's set up wb */
 756         wb->left = prefix_len + wr->length;
 757         wb->offset = 0;
 758
 759         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
 760         s->s3->wpend_tot=len;
 761         s->s3->wpend_buf=buf;
 762         s->s3->wpend_type=type;
 763         s->s3->wpend_ret=len;
 764
 765         /* we now just need to write the buffer */
 766         return ssl3_write_pending(s,type,buf,len);
 767 err:
 768         return -1;
 769         }
 770
 771 /* if s->s3->wbuf.left != 0, we need to call this */
 772 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 773         unsigned int len)
 774         {
 775         int i;
 776
 777 /* XXXX */
 778         if ((s->s3->wpend_tot > (int)len)
 779                 || ((s->s3->wpend_buf != buf) &&
 780                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 781                 || (s->s3->wpend_type != type))
 782                 {
 783                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 784                 return(-1);
 785                 }
 786
 787         for (;;)
 788                 {
 789                 clear_sys_error();
 790                 if (s->wbio != NULL)
 791                         {
 792                         s->rwstate=SSL_WRITING;
 793                         i=BIO_write(s->wbio,
 794                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
 795                                 (unsigned int)s->s3->wbuf.left);
 796                         }
 797                 else
 798                         {
 799                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 800                         i= -1;
 801                         }
 802                 if (i == s->s3->wbuf.left)
 803                         {
 804                         s->s3->wbuf.left=0;
 805                         s->rwstate=SSL_NOTHING;
 806                         return(s->s3->wpend_ret);
 807                         }
 808                 else if (i <= 0) {
 809                         if (s->version == DTLS1_VERSION ||
 810                             s->version == DTLS1_BAD_VER) {
 811                                 /* For DTLS, just drop it. That's kind of the whole
 812                                    point in using a datagram service */
 813                                 s->s3->wbuf.left = 0;
 814                         }
 815                         return(i);
 816                 }
 817                 s->s3->wbuf.offset+=i;
 818                 s->s3->wbuf.left-=i;
 819                 }
 820         }
 821
 822 /* Return up to 'len' payload bytes received in 'type' records.
 823  * 'type' is one of the following:
 824  *
 825  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 826  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 827  *   -  0 (during a shutdown, no data has to be returned)
 828  *
 829  * If we don't have stored data to work from, read a SSL/TLS record first
 830  * (possibly multiple records if we still don't have anything to return).
 831  *
 832  * This function must handle any surprises the peer may have for us, such as
 833  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 834  * a surprise, but handled as if it were), or renegotiation requests.
 835  * Also if record payloads contain fragments too small to process, we store
 836  * them until there is enough for the respective protocol (the record protocol
 837  * may use arbitrary fragmentation and even interleaving):
 838  *     Change cipher spec protocol
 839  *             just 1 byte needed, no need for keeping anything stored
 840  *     Alert protocol
 841  *             2 bytes needed (AlertLevel, AlertDescription)
 842  *     Handshake protocol
 843  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 844  *             to detect unexpected Client Hello and Hello Request messages
 845  *             here, anything else is handled by higher layers
 846  *     Application data protocol
 847  *             none of our business
 848  */
 849 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 850         {
 851         int al,i,j,ret;
 852         unsigned int n;
 853         SSL3_RECORD *rr;
 854         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 855
 856         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 857                 if (!ssl3_setup_buffers(s))
 858                         return(-1);
 859
 860         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) ||
 861             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 862                 {
 863                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
 864                 return -1;
 865                 }
 866
 867         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 868                 /* (partially) satisfy request from storage */
 869                 {
 870                 unsigned char *src = s->s3->handshake_fragment;
 871                 unsigned char *dst = buf;
 872                 unsigned int k;
 873
 874                 /* peek == 0 */
 875                 n = 0;
 876                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 877                         {
 878                         *dst++ = *src++;
 879                         len--; s->s3->handshake_fragment_len--;
 880                         n++;
 881                         }
 882                 /* move any remaining fragment bytes: */
 883                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
 884                         s->s3->handshake_fragment[k] = *src++;
 885                 return n;
 886         }
 887
 888         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 889
 890         if (!s->in_handshake && SSL_in_init(s))
 891                 {
 892                 /* type == SSL3_RT_APPLICATION_DATA */
 893                 i=s->handshake_func(s);
 894                 if (i < 0) return(i);
 895                 if (i == 0)
 896                         {
 897                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 898                         return(-1);
 899                         }
 900                 }
 901 start:
 902         s->rwstate=SSL_NOTHING;
 903
 904         /* s->s3->rrec.type         - is the type of record
 905          * s->s3->rrec.data,    - data
 906          * s->s3->rrec.off,     - offset into 'data' for next read
 907          * s->s3->rrec.length,  - number of bytes. */
 908         rr = &(s->s3->rrec);
 909
 910         /* get new packet if necessary */
 911         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 912                 {
 913                 ret=ssl3_get_record(s);
 914                 if (ret <= 0) return(ret);
 915                 }
 916
 917         /* we now have a packet which can be read and processed */
 918
 919         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 920                                        * reset by ssl3_get_finished */
 921                 && (rr->type != SSL3_RT_HANDSHAKE))
 922                 {
 923                 al=SSL_AD_UNEXPECTED_MESSAGE;
 924                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 925                 goto f_err;
 926                 }
 927
 928         /* If the other end has shut down, throw anything we read away
 929          * (even in 'peek' mode) */
 930         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 931                 {
 932                 rr->length=0;
 933                 s->rwstate=SSL_NOTHING;
 934                 return(0);
 935                 }
 936
 937
 938         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 939                 {
 940                 /* make sure that we are not getting application data when we
 941                  * are doing a handshake for the first time */
 942                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 943                         (s->enc_read_ctx == NULL))
 944                         {
 945                         al=SSL_AD_UNEXPECTED_MESSAGE;
 946                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 947                         goto f_err;
 948                         }
 949
 950                 if (len <= 0) return(len);
 951
 952                 if ((unsigned int)len > rr->length)
 953                         n = rr->length;
 954                 else
 955                         n = (unsigned int)len;
 956
 957                 memcpy(buf,&(rr->data[rr->off]),n);
 958                 if (!peek)
 959                         {
 960                         rr->length-=n;
 961                         rr->off+=n;
 962                         if (rr->length == 0)
 963                                 {
 964                                 s->rstate=SSL_ST_READ_HEADER;
 965                                 rr->off=0;
 966                                 }
 967                         }
 968                 return(n);
 969                 }
 970
 971
 972         /* If we get here, then type != rr->type; if we have a handshake
 973          * message, then it was unexpected (Hello Request or Client Hello). */
 974
 975         /* In case of record types for which we have 'fragment' storage,
 976          * fill that so that we can process the data at a fixed place.
 977          */
 978                 {
 979                 unsigned int dest_maxlen = 0;
 980                 unsigned char *dest = NULL;
 981                 unsigned int *dest_len = NULL;
 982
 983                 if (rr->type == SSL3_RT_HANDSHAKE)
 984                         {
 985                         dest_maxlen = sizeof s->s3->handshake_fragment;
 986                         dest = s->s3->handshake_fragment;
 987                         dest_len = &s->s3->handshake_fragment_len;
 988                         }
 989                 else if (rr->type == SSL3_RT_ALERT)
 990                         {
 991                         dest_maxlen = sizeof s->s3->alert_fragment;
 992                         dest = s->s3->alert_fragment;
 993                         dest_len = &s->s3->alert_fragment_len;
 994                         }
 995
 996                 if (dest_maxlen > 0)
 997                         {
 998                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
 999                         if (rr->length < n)
1000                                 n = rr->length; /* available bytes */
1001
1002                         /* now move 'n' bytes: */
1003                         while (n-- > 0)
1004                                 {
1005                                 dest[(*dest_len)++] = rr->data[rr->off++];
1006                                 rr->length--;
1007                                 }
1008
1009                         if (*dest_len < dest_maxlen)
1010                                 goto start; /* fragment was too small */
1011                         }
1012                 }
1013
1014         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1015          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1016          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1017
1018         /* If we are a client, check for an incoming 'Hello Request': */
1019         if ((!s->server) &&
1020                 (s->s3->handshake_fragment_len >= 4) &&
1021                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1022                 (s->session != NULL) && (s->session->cipher != NULL))
1023                 {
1024                 s->s3->handshake_fragment_len = 0;
1025
1026                 if ((s->s3->handshake_fragment[1] != 0) ||
1027                         (s->s3->handshake_fragment[2] != 0) ||
1028                         (s->s3->handshake_fragment[3] != 0))
1029                         {
1030                         al=SSL_AD_DECODE_ERROR;
1031                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1032                         goto f_err;
1033                         }
1034
1035                 if (s->msg_callback)
1036                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1037
1038                 if (SSL_is_init_finished(s) &&
1039                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1040                         !s->s3->renegotiate)
1041                         {
1042                         ssl3_renegotiate(s);
1043                         if (ssl3_renegotiate_check(s))
1044                                 {
1045                                 i=s->handshake_func(s);
1046                                 if (i < 0) return(i);
1047                                 if (i == 0)
1048                                         {
1049                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1050                                         return(-1);
1051                                         }
1052
1053                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1054                                         {
1055                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1056                                                 {
1057                                                 BIO *bio;
1058                                                 /* In the case where we try to read application data,
1059                                                  * but we trigger an SSL handshake, we return -1 with
1060                                                  * the retry option set.  Otherwise renegotiation may
1061                                                  * cause nasty problems in the blocking world */
1062                                                 s->rwstate=SSL_READING;
1063                                                 bio=SSL_get_rbio(s);
1064                                                 BIO_clear_retry_flags(bio);
1065                                                 BIO_set_retry_read(bio);
1066                                                 return(-1);
1067                                                 }
1068                                         }
1069                                 }
1070                         }
1071                 /* we either finished a handshake or ignored the request,
1072                  * now try again to obtain the (application) data we were asked for */
1073                 goto start;
1074                 }
1075         /* If we are a server and get a client hello when renegotiation isn't
1076          * allowed send back a no renegotiation alert and carry on.
1077          * WARNING: experimental code, needs reviewing (steve)
1078          */
1079         if (s->server &&
1080                 SSL_is_init_finished(s) &&
1081                 !s->s3->send_connection_binding &&
1082                 (s->version > SSL3_VERSION) &&
1083                 (s->s3->handshake_fragment_len >= 4) &&
1084                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1085                 (s->session != NULL) && (s->session->cipher != NULL) &&
1086                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1087
1088                 {
1089                 /*s->s3->handshake_fragment_len = 0;*/
1090                 rr->length = 0;
1091                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1092                 goto start;
1093                 }
1094         if (s->s3->alert_fragment_len >= 2)
1095                 {
1096                 int alert_level = s->s3->alert_fragment[0];
1097                 int alert_descr = s->s3->alert_fragment[1];
1098
1099                 s->s3->alert_fragment_len = 0;
1100
1101                 if (s->msg_callback)
1102                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1103
1104                 if (s->info_callback != NULL)
1105                         cb=s->info_callback;
1106                 else if (s->ctx->info_callback != NULL)
1107                         cb=s->ctx->info_callback;
1108
1109                 if (cb != NULL)
1110                         {
1111                         j = (alert_level << 8) | alert_descr;
1112                         cb(s, SSL_CB_READ_ALERT, j);
1113                         }
1114
1115                 if (alert_level == 1) /* warning */
1116                         {
1117                         s->s3->warn_alert = alert_descr;
1118                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1119                                 {
1120                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1121                                 return(0);
1122                                 }
1123                         /* This is a warning but we receive it if we requested
1124                          * renegotiation and the peer denied it. Terminate with
1125                          * a fatal alert because if application tried to
1126                          * renegotiatie it presumably had a good reason and
1127                          * expects it to succeed.
1128                          *
1129                          * In future we might have a renegotiation where we
1130                          * don't care if the peer refused it where we carry on.
1131                          */
1132                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1133                                 {
1134                                 al = SSL_AD_HANDSHAKE_FAILURE;
1135                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1136                                 goto f_err;
1137                                 }
1138                         }
1139                 else if (alert_level == 2) /* fatal */
1140                         {
1141                         char tmp[16];
1142
1143                         s->rwstate=SSL_NOTHING;
1144                         s->s3->fatal_alert = alert_descr;
1145                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1146                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1147                         ERR_add_error_data(2,"SSL alert number ",tmp);
1148                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1149                         SSL_CTX_remove_session(s->ctx,s->session);
1150                         return(0);
1151                         }
1152                 else
1153                         {
1154                         al=SSL_AD_ILLEGAL_PARAMETER;
1155                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1156                         goto f_err;
1157                         }
1158
1159                 goto start;
1160                 }
1161
1162         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1163                 {
1164                 s->rwstate=SSL_NOTHING;
1165                 rr->length=0;
1166                 return(0);
1167                 }
1168
1169         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1170                 {
1171                 /* 'Change Cipher Spec' is just a single byte, so we know
1172                  * exactly what the record payload has to look like */
1173                 if (    (rr->length != 1) || (rr->off != 0) ||
1174                         (rr->data[0] != SSL3_MT_CCS))
1175                         {
1176                         al=SSL_AD_ILLEGAL_PARAMETER;
1177                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1178                         goto f_err;
1179                         }
1180
1181                 /* Check we have a cipher to change to */
1182                 if (s->s3->tmp.new_cipher == NULL)
1183                         {
1184                         al=SSL_AD_UNEXPECTED_MESSAGE;
1185                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1186                         goto f_err;
1187                         }
1188
1189                 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1190                         {
1191                         al=SSL_AD_UNEXPECTED_MESSAGE;
1192                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1193                         goto f_err;
1194                         }
1195
1196                 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1197
1198                 rr->length=0;
1199
1200                 if (s->msg_callback)
1201                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1202
1203                 s->s3->change_cipher_spec=1;
1204                 if (!ssl3_do_change_cipher_spec(s))
1205                         goto err;
1206                 else
1207                         goto start;
1208                 }
1209
1210         /* Unexpected handshake message (Client Hello, or protocol violation) */
1211         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1212                 {
1213                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1214                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1215                         {
1216 #if 0 /* worked only because C operator preferences are not as expected (and
1217        * because this is not really needed for clients except for detecting
1218        * protocol violations): */
1219                         s->state=SSL_ST_BEFORE|(s->server)
1220                                 ?SSL_ST_ACCEPT
1221                                 :SSL_ST_CONNECT;
1222 #else
1223                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1224 #endif
1225                         s->new_session=1;
1226                         }
1227                 i=s->handshake_func(s);
1228                 if (i < 0) return(i);
1229                 if (i == 0)
1230                         {
1231                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1232                         return(-1);
1233                         }
1234
1235                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1236                         {
1237                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1238                                 {
1239                                 BIO *bio;
1240                                 /* In the case where we try to read application data,
1241                                  * but we trigger an SSL handshake, we return -1 with
1242                                  * the retry option set.  Otherwise renegotiation may
1243                                  * cause nasty problems in the blocking world */
1244                                 s->rwstate=SSL_READING;
1245                                 bio=SSL_get_rbio(s);
1246                                 BIO_clear_retry_flags(bio);
1247                                 BIO_set_retry_read(bio);
1248                                 return(-1);
1249                                 }
1250                         }
1251                 goto start;
1252                 }
1253
1254         switch (rr->type)
1255                 {
1256         default:
1257 #ifndef OPENSSL_NO_TLS
1258                 /* TLS just ignores unknown message types */
1259                 if (s->version == TLS1_VERSION)
1260                         {
1261                         rr->length = 0;
1262                         goto start;
1263                         }
1264 #endif
1265                 al=SSL_AD_UNEXPECTED_MESSAGE;
1266                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1267                 goto f_err;
1268         case SSL3_RT_CHANGE_CIPHER_SPEC:
1269         case SSL3_RT_ALERT:
1270         case SSL3_RT_HANDSHAKE:
1271                 /* we already handled all of these, with the possible exception
1272                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1273                  * should not happen when type != rr->type */
1274                 al=SSL_AD_UNEXPECTED_MESSAGE;
1275                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1276                 goto f_err;
1277         case SSL3_RT_APPLICATION_DATA:
1278                 /* At this point, we were expecting handshake data,
1279                  * but have application data.  If the library was
1280                  * running inside ssl3_read() (i.e. in_read_app_data
1281                  * is set) and it makes sense to read application data
1282                  * at this point (session renegotiation not yet started),
1283                  * we will indulge it.
1284                  */
1285                 if (s->s3->in_read_app_data &&
1286                         (s->s3->total_renegotiations != 0) &&
1287                         ((
1288                                 (s->state & SSL_ST_CONNECT) &&
1289                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1290                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1291                                 ) || (
1292                                         (s->state & SSL_ST_ACCEPT) &&
1293                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1294                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1295                                         )
1296                                 ))
1297                         {
1298                         s->s3->in_read_app_data=2;
1299                         return(-1);
1300                         }
1301                 else
1302                         {
1303                         al=SSL_AD_UNEXPECTED_MESSAGE;
1304                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1305                         goto f_err;
1306                         }
1307                 }
1308         /* not reached */
1309
1310 f_err:
1311         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1312 err:
1313         return(-1);
1314         }
1315
1316 int ssl3_do_change_cipher_spec(SSL *s)
1317         {
1318         int i;
1319         const char *sender;
1320         int slen;
1321
1322         if (s->state & SSL_ST_ACCEPT)
1323                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1324         else
1325                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1326
1327         if (s->s3->tmp.key_block == NULL)
1328                 {
1329                 if (s->session == NULL || s->session->master_key_length == 0)
1330                         {
1331                         /* might happen if dtls1_read_bytes() calls this */
1332                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1333                         return (0);
1334                         }
1335
1336                 s->session->cipher=s->s3->tmp.new_cipher;
1337                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1338                 }
1339
1340         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1341                 return(0);
1342
1343         /* we have to record the message digest at
1344          * this point so we can get it before we read
1345          * the finished message */
1346         if (s->state & SSL_ST_CONNECT)
1347                 {
1348                 sender=s->method->ssl3_enc->server_finished_label;
1349                 slen=s->method->ssl3_enc->server_finished_label_len;
1350                 }
1351         else
1352                 {
1353                 sender=s->method->ssl3_enc->client_finished_label;
1354                 slen=s->method->ssl3_enc->client_finished_label_len;
1355                 }
1356
1357         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1358                 &(s->s3->finish_dgst1),
1359                 &(s->s3->finish_dgst2),
1360                 sender,slen,s->s3->tmp.peer_finish_md);
1361
1362         return(1);
1363         }
1364
1365 int ssl3_send_alert(SSL *s, int level, int desc)
1366         {
1367         /* Map tls/ssl alert value to correct one */
1368         desc=s->method->ssl3_enc->alert_value(desc);
1369         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1370                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1371         if (desc < 0) return -1;
1372         /* If a fatal one, remove from cache */
1373         if ((level == 2) && (s->session != NULL))
1374                 SSL_CTX_remove_session(s->ctx,s->session);
1375
1376         s->s3->alert_dispatch=1;
1377         s->s3->send_alert[0]=level;
1378         s->s3->send_alert[1]=desc;
1379         if (s->s3->wbuf.left == 0) /* data still being written out? */
1380                 return s->method->ssl_dispatch_alert(s);
1381         /* else data is still being written out, we will get written
1382          * some time in the future */
1383         return -1;
1384         }
1385
1386 int ssl3_dispatch_alert(SSL *s)
1387         {
1388         int i,j;
1389         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1390
1391         s->s3->alert_dispatch=0;
1392         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1393         if (i <= 0)
1394                 {
1395                 s->s3->alert_dispatch=1;
1396                 }
1397         else
1398                 {
1399                 /* Alert sent to BIO.  If it is important, flush it now.
1400                  * If the message does not get sent due to non-blocking IO,
1401                  * we will not worry too much. */
1402                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1403                         (void)BIO_flush(s->wbio);
1404
1405                 if (s->msg_callback)
1406                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1407
1408                 if (s->info_callback != NULL)
1409                         cb=s->info_callback;
1410                 else if (s->ctx->info_callback != NULL)
1411                         cb=s->ctx->info_callback;
1412
1413                 if (cb != NULL)
1414                         {
1415                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1416                         cb(s,SSL_CB_WRITE_ALERT,j);
1417                         }
1418                 }
1419         return(i);
1420         }