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 <errno.h>
 114 #define USE_SOCKETS
 115 #include "ssl_locl.h"
 116 #include <openssl/evp.h>
 117 #include <openssl/buffer.h>
 118
 119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 120                          unsigned int len, int create_empty_fragment);
 121 static int ssl3_get_record(SSL *s);
 122
 123 int ssl3_read_n(SSL *s, int n, int max, int extend)
 124         {
 125         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
 126          * packet by another n bytes.
 127          * The packet will be in the sub-array of s->s3->rbuf.buf specified
 128          * by s->packet and s->packet_length.
 129          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
 130          * [plus s->packet_length bytes if extend == 1].)
 131          */
 132         int i,off,newb;
 133
 134         if (!extend)
 135                 {
 136                 /* start with empty packet ... */
 137                 if (s->s3->rbuf.left == 0)
 138                         s->s3->rbuf.offset = 0;
 139                 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
 140                 s->packet_length = 0;
 141                 /* ... now we can act as if 'extend' was set */
 142                 }
 143
 144         /* For DTLS/UDP reads should not span multiple packets
 145          * because the read operation returns the whole packet
 146          * at once (as long as it fits into the buffer). */
 147         if (SSL_version(s) == DTLS1_VERSION)
 148                 {
 149                 if (s->s3->rbuf.left == 0 && extend)
 150                         return 0;
 151                 if ( s->s3->rbuf.left > 0 && n > s->s3->rbuf.left)
 152                         n = s->s3->rbuf.left;
 153                 }
 154
 155         /* if there is enough in the buffer from a previous read, take some */
 156         if (s->s3->rbuf.left >= (int)n)
 157                 {
 158                 s->packet_length+=n;
 159                 s->s3->rbuf.left-=n;
 160                 s->s3->rbuf.offset+=n;
 161                 return(n);
 162                 }
 163
 164         /* else we need to read more data */
 165         if (!s->read_ahead)
 166                 max=n;
 167
 168         {
 169                 /* avoid buffer overflow */
 170                 int max_max = s->s3->rbuf.len - s->packet_length;
 171                 if (max > max_max)
 172                         max = max_max;
 173         }
 174         if (n > max) /* does not happen */
 175                 {
 176                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 177                 return -1;
 178                 }
 179
 180         off = s->packet_length;
 181         newb = s->s3->rbuf.left;
 182         /* Move any available bytes to front of buffer:
 183          * 'off' bytes already pointed to by 'packet',
 184          * 'newb' extra ones at the end */
 185         if (s->packet != s->s3->rbuf.buf)
 186                 {
 187                 /*  off > 0 */
 188                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
 189                 s->packet = s->s3->rbuf.buf;
 190                 }
 191
 192         while (newb < n)
 193                 {
 194                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
 195                  * to read in more until we have off+n (up to off+max if possible) */
 196
 197                 clear_sys_error();
 198                 if (s->rbio != NULL)
 199                         {
 200                         s->rwstate=SSL_READING;
 201                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
 202                         }
 203                 else
 204                         {
 205                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 206                         i = -1;
 207                         }
 208
 209                 if (i <= 0)
 210                         {
 211                         s->s3->rbuf.left = newb;
 212                         return(i);
 213                         }
 214                 newb+=i;
 215                 /* reads should *never* span multiple packets for DTLS because
 216                  * the underlying transport protocol is message oriented as opposed
 217                  * to byte oriented as in the TLS case. */
 218                 if (SSL_version(s) == DTLS1_VERSION)
 219                         {
 220                         if (n > newb)
 221                                 n = newb; /* makes the while condition false */
 222                         }
 223                 }
 224
 225         /* done reading, now the book-keeping */
 226         s->s3->rbuf.offset = off + n;
 227         s->s3->rbuf.left = newb - n;
 228         s->packet_length += n;
 229         s->rwstate=SSL_NOTHING;
 230         return(n);
 231         }
 232
 233 /* Call this to get a new input record.
 234  * It will return <= 0 if more data is needed, normally due to an error
 235  * or non-blocking IO.
 236  * When it finishes, one packet has been decoded and can be found in
 237  * ssl->s3->rrec.type    - is the type of record
 238  * ssl->s3->rrec.data,   - data
 239  * ssl->s3->rrec.length, - number of bytes
 240  */
 241 /* used only by ssl3_read_bytes */
 242 static int ssl3_get_record(SSL *s)
 243         {
 244         int ssl_major,ssl_minor,al;
 245         int enc_err,n,i,ret= -1;
 246         SSL3_RECORD *rr;
 247         SSL_SESSION *sess;
 248         unsigned char *p;
 249         unsigned char md[EVP_MAX_MD_SIZE];
 250         short version;
 251         unsigned mac_size, orig_len;
 252         size_t extra;
 253
 254         rr= &(s->s3->rrec);
 255         sess=s->session;
 256
 257         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 258                 extra=SSL3_RT_MAX_EXTRA;
 259         else
 260                 extra=0;
 261         if (extra != s->s3->rbuf.len - SSL3_RT_MAX_PACKET_SIZE)
 262                 {
 263                 /* actually likely an application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
 264                  * set after ssl3_setup_buffers() was done */
 265                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
 266                 return -1;
 267                 }
 268
 269 again:
 270         /* check if we have the header */
 271         if (    (s->rstate != SSL_ST_READ_BODY) ||
 272                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 273                 {
 274                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 275                 if (n <= 0) return(n); /* error or non-blocking */
 276                 s->rstate=SSL_ST_READ_BODY;
 277
 278                 p=s->packet;
 279
 280                 /* Pull apart the header into the SSL3_RECORD */
 281                 rr->type= *(p++);
 282                 ssl_major= *(p++);
 283                 ssl_minor= *(p++);
 284                 version=(ssl_major<<8)|ssl_minor;
 285                 n2s(p,rr->length);
 286
 287                 /* Lets check version */
 288                 if (!s->first_packet)
 289                         {
 290                         if (version != s->version)
 291                                 {
 292                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 293                                 if ((s->version & 0xFF00) == (version & 0xFF00))
 294                                         /* Send back error using their minor version number :-) */
 295                                         s->version = (unsigned short)version;
 296                                 al=SSL_AD_PROTOCOL_VERSION;
 297                                 goto f_err;
 298                                 }
 299                         }
 300
 301                 if ((version>>8) != SSL3_VERSION_MAJOR)
 302                         {
 303                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 304                         goto err;
 305                         }
 306
 307                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 308                         {
 309                         al=SSL_AD_RECORD_OVERFLOW;
 310                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 311                         goto f_err;
 312                         }
 313
 314                 /* now s->rstate == SSL_ST_READ_BODY */
 315                 }
 316
 317         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 318
 319         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
 320                 {
 321                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
 322                 i=rr->length;
 323                 n=ssl3_read_n(s,i,i,1);
 324                 if (n <= 0) return(n); /* error or non-blocking io */
 325                 /* now n == rr->length,
 326                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
 327                 }
 328
 329         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 330
 331         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 332          * and we have that many bytes in s->packet
 333          */
 334         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 335
 336         /* ok, we can now read from 's->packet' data into 'rr'
 337          * rr->input points at rr->length bytes, which
 338          * need to be copied into rr->data by either
 339          * the decryption or by the decompression
 340          * When the data is 'copied' into the rr->data buffer,
 341          * rr->input will be pointed at the new buffer */
 342
 343         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 344          * rr->length bytes of encrypted compressed stuff. */
 345
 346         /* check is not needed I believe */
 347         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 348                 {
 349                 al=SSL_AD_RECORD_OVERFLOW;
 350                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 351                 goto f_err;
 352                 }
 353
 354         /* decrypt in place in 'rr->input' */
 355         rr->data=rr->input;
 356
 357         enc_err = s->method->ssl3_enc->enc(s,0);
 358         /* enc_err is:
 359          *    0: (in non-constant time) if the record is publically invalid.
 360          *    1: if the padding is valid
 361          *    -1: if the padding is invalid */
 362         if (enc_err == 0)
 363                 {
 364                 al=SSL_AD_DECRYPTION_FAILED;
 365                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
 366                 goto f_err;
 367                 }
 368
 369 #ifdef TLS_DEBUG
 370 printf("dec %d\n",rr->length);
 371 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 372 printf("\n");
 373 #endif
 374
 375         /* r->length is now the compressed data plus mac */
 376         if ((sess != NULL) &&
 377             (s->enc_read_ctx != NULL) &&
 378             (s->read_hash != NULL))
 379                 {
 380                 /* s->read_hash != NULL => mac_size != -1 */
 381                 unsigned char *mac = NULL;
 382                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 383                 mac_size=EVP_MD_size(s->read_hash);
 384                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 385
 386                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 387                 orig_len = rr->length+((unsigned int)rr->type>>8);
 388
 389                 /* orig_len is the length of the record before any padding was
 390                  * removed. This is public information, as is the MAC in use,
 391                  * therefore we can safely process the record in a different
 392                  * amount of time if it's too short to possibly contain a MAC.
 393                  */
 394                 if (orig_len < mac_size ||
 395                     /* CBC records must have a padding length byte too. */
 396                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 397                      orig_len < mac_size+1))
 398                         {
 399                         al=SSL_AD_DECODE_ERROR;
 400                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 401                         goto f_err;
 402                         }
 403
 404                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 405                         {
 406                         /* We update the length so that the TLS header bytes
 407                          * can be constructed correctly but we need to extract
 408                          * the MAC in constant time from within the record,
 409                          * without leaking the contents of the padding bytes.
 410                          * */
 411                         mac = mac_tmp;
 412                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 413                         rr->length -= mac_size;
 414                         }
 415                 else
 416                         {
 417                         /* In this case there's no padding, so |orig_len|
 418                          * equals |rec->length| and we checked that there's
 419                          * enough bytes for |mac_size| above. */
 420                         rr->length -= mac_size;
 421                         mac = &rr->data[rr->length];
 422                         }
 423
 424                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 425                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 426                         enc_err = -1;
 427                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 428                         enc_err = -1;
 429                 }
 430
 431         if (enc_err < 0)
 432                 {
 433                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
 434                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
 435                  * failure is directly visible from the ciphertext anyway,
 436                  * we should not reveal which kind of error occured -- this
 437                  * might become visible to an attacker (e.g. via a logfile) */
 438                 al=SSL_AD_BAD_RECORD_MAC;
 439                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
 440                 goto f_err;
 441                 }
 442
 443         /* r->length is now just compressed */
 444         if (s->expand != NULL)
 445                 {
 446                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 447                         {
 448                         al=SSL_AD_RECORD_OVERFLOW;
 449                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 450                         goto f_err;
 451                         }
 452                 if (!ssl3_do_uncompress(s))
 453                         {
 454                         al=SSL_AD_DECOMPRESSION_FAILURE;
 455                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 456                         goto f_err;
 457                         }
 458                 }
 459
 460         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
 461                 {
 462                 al=SSL_AD_RECORD_OVERFLOW;
 463                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 464                 goto f_err;
 465                 }
 466
 467         rr->off=0;
 468         /* So at this point the following is true
 469          * ssl->s3->rrec.type   is the type of record
 470          * ssl->s3->rrec.length == number of bytes in record
 471          * ssl->s3->rrec.off    == offset to first valid byte
 472          * ssl->s3->rrec.data   == where to take bytes from, increment
 473          *                         after use :-).
 474          */
 475
 476         /* we have pulled in a full packet so zero things */
 477         s->packet_length=0;
 478
 479         /* just read a 0 length packet */
 480         if (rr->length == 0) goto again;
 481
 482         return(1);
 483
 484 f_err:
 485         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 486 err:
 487         return(ret);
 488         }
 489
 490 int ssl3_do_uncompress(SSL *ssl)
 491         {
 492 #ifndef OPENSSL_NO_COMP
 493         int i;
 494         SSL3_RECORD *rr;
 495
 496         rr= &(ssl->s3->rrec);
 497         i=COMP_expand_block(ssl->expand,rr->comp,
 498                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 499         if (i < 0)
 500                 return(0);
 501         else
 502                 rr->length=i;
 503         rr->data=rr->comp;
 504 #endif
 505         return(1);
 506         }
 507
 508 int ssl3_do_compress(SSL *ssl)
 509         {
 510 #ifndef OPENSSL_NO_COMP
 511         int i;
 512         SSL3_RECORD *wr;
 513
 514         wr= &(ssl->s3->wrec);
 515         i=COMP_compress_block(ssl->compress,wr->data,
 516                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 517                 wr->input,(int)wr->length);
 518         if (i < 0)
 519                 return(0);
 520         else
 521                 wr->length=i;
 522
 523         wr->input=wr->data;
 524 #endif
 525         return(1);
 526         }
 527
 528 /* Call this to write data in records of type 'type'
 529  * It will return <= 0 if not all data has been sent or non-blocking IO.
 530  */
 531 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 532         {
 533         const unsigned char *buf=buf_;
 534         unsigned int n,nw;
 535         int i,tot;
 536
 537         s->rwstate=SSL_NOTHING;
 538         OPENSSL_assert(s->s3->wnum < INT_MAX);
 539         tot=s->s3->wnum;
 540         s->s3->wnum=0;
 541
 542         if (SSL_in_init(s) && !s->in_handshake)
 543                 {
 544                 i=s->handshake_func(s);
 545                 if (i < 0) return(i);
 546                 if (i == 0)
 547                         {
 548                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 549                         return -1;
 550                         }
 551                 }
 552
 553         /* ensure that if we end up with a smaller value of data to write
 554          * out than the the original len from a write which didn't complete
 555          * for non-blocking I/O and also somehow ended up avoiding
 556          * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
 557          * it must never be possible to end up with (len-tot) as a large
 558          * number that will then promptly send beyond the end of the users
 559          * buffer ... so we trap and report the error in a way the user
 560          * will notice
 561          */
 562         if (len < tot)
 563                 {
 564                 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
 565                 return(-1);
 566                 }
 567
 568
 569         n=(len-tot);
 570         for (;;)
 571                 {
 572                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
 573                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
 574                 else
 575                         nw=n;
 576
 577                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
 578                 if (i <= 0)
 579                         {
 580                         s->s3->wnum=tot;
 581                         return i;
 582                         }
 583
 584                 if ((i == (int)n) ||
 585                         (type == SSL3_RT_APPLICATION_DATA &&
 586                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 587                         {
 588                         /* next chunk of data should get another prepended empty fragment
 589                          * in ciphersuites with known-IV weakness: */
 590                         s->s3->empty_fragment_done = 0;
 591
 592                         return tot+i;
 593                         }
 594
 595                 n-=i;
 596                 tot+=i;
 597                 }
 598         }
 599
 600 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 601                          unsigned int len, int create_empty_fragment)
 602         {
 603         unsigned char *p,*plen;
 604         int i,mac_size,clear=0;
 605         int prefix_len = 0;
 606         SSL3_RECORD *wr;
 607         SSL3_BUFFER *wb;
 608         SSL_SESSION *sess;
 609
 610         /* first check if there is a SSL3_BUFFER still being written
 611          * out.  This will happen with non blocking IO */
 612         if (s->s3->wbuf.left != 0)
 613                 return(ssl3_write_pending(s,type,buf,len));
 614
 615         /* If we have an alert to send, lets send it */
 616         if (s->s3->alert_dispatch)
 617                 {
 618                 i=s->method->ssl_dispatch_alert(s);
 619                 if (i <= 0)
 620                         return(i);
 621                 /* if it went, fall through and send more stuff */
 622                 }
 623
 624         if (len == 0 && !create_empty_fragment)
 625                 return 0;
 626
 627         wr= &(s->s3->wrec);
 628         wb= &(s->s3->wbuf);
 629         sess=s->session;
 630
 631         if (    (sess == NULL) ||
 632                 (s->enc_write_ctx == NULL) ||
 633                 (s->write_hash == NULL))
 634                 clear=1;
 635
 636         if (clear)
 637                 mac_size=0;
 638         else
 639                 mac_size=EVP_MD_size(s->write_hash);
 640
 641         /* 'create_empty_fragment' is true only when this function calls itself */
 642         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
 643                 {
 644                 /* countermeasure against known-IV weakness in CBC ciphersuites
 645                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
 646
 647                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
 648                         {
 649                         /* recursive function call with 'create_empty_fragment' set;
 650                          * this prepares and buffers the data for an empty fragment
 651                          * (these 'prefix_len' bytes are sent out later
 652                          * together with the actual payload) */
 653                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
 654                         if (prefix_len <= 0)
 655                                 goto err;
 656
 657                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
 658                                 {
 659                                 /* insufficient space */
 660                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
 661                                 goto err;
 662                                 }
 663                         }
 664
 665                 s->s3->empty_fragment_done = 1;
 666                 }
 667
 668         p = wb->buf + prefix_len;
 669
 670         /* write the header */
 671
 672         *(p++)=type&0xff;
 673         wr->type=type;
 674
 675         *(p++)=(s->version>>8);
 676         *(p++)=s->version&0xff;
 677
 678         /* field where we are to write out packet length */
 679         plen=p;
 680         p+=2;
 681
 682         /* lets setup the record stuff. */
 683         wr->data=p;
 684         wr->length=(int)len;
 685         wr->input=(unsigned char *)buf;
 686
 687         /* we now 'read' from wr->input, wr->length bytes into
 688          * wr->data */
 689
 690         /* first we compress */
 691         if (s->compress != NULL)
 692                 {
 693                 if (!ssl3_do_compress(s))
 694                         {
 695                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 696                         goto err;
 697                         }
 698                 }
 699         else
 700                 {
 701                 memcpy(wr->data,wr->input,wr->length);
 702                 wr->input=wr->data;
 703                 }
 704
 705         /* we should still have the output to wr->data and the input
 706          * from wr->input.  Length should be wr->length.
 707          * wr->data still points in the wb->buf */
 708
 709         if (mac_size != 0)
 710                 {
 711                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
 712                 wr->length+=mac_size;
 713                 wr->input=p;
 714                 wr->data=p;
 715                 }
 716
 717         /* ssl3_enc can only have an error on read */
 718         s->method->ssl3_enc->enc(s,1);
 719
 720         /* record length after mac and block padding */
 721         s2n(wr->length,plen);
 722
 723         /* we should now have
 724          * wr->data pointing to the encrypted data, which is
 725          * wr->length long */
 726         wr->type=type; /* not needed but helps for debugging */
 727         wr->length+=SSL3_RT_HEADER_LENGTH;
 728
 729         if (create_empty_fragment)
 730                 {
 731                 /* we are in a recursive call;
 732                  * just return the length, don't write out anything here
 733                  */
 734                 return wr->length;
 735                 }
 736
 737         /* now let's set up wb */
 738         wb->left = prefix_len + wr->length;
 739         wb->offset = 0;
 740
 741         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
 742         s->s3->wpend_tot=len;
 743         s->s3->wpend_buf=buf;
 744         s->s3->wpend_type=type;
 745         s->s3->wpend_ret=len;
 746
 747         /* we now just need to write the buffer */
 748         return ssl3_write_pending(s,type,buf,len);
 749 err:
 750         return -1;
 751         }
 752
 753 /* if s->s3->wbuf.left != 0, we need to call this */
 754 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 755         unsigned int len)
 756         {
 757         int i;
 758
 759 /* XXXX */
 760         if ((s->s3->wpend_tot > (int)len)
 761                 || ((s->s3->wpend_buf != buf) &&
 762                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 763                 || (s->s3->wpend_type != type))
 764                 {
 765                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 766                 return(-1);
 767                 }
 768
 769         for (;;)
 770                 {
 771                 clear_sys_error();
 772                 if (s->wbio != NULL)
 773                         {
 774                         s->rwstate=SSL_WRITING;
 775                         i=BIO_write(s->wbio,
 776                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
 777                                 (unsigned int)s->s3->wbuf.left);
 778                         }
 779                 else
 780                         {
 781                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 782                         i= -1;
 783                         }
 784                 if (i == s->s3->wbuf.left)
 785                         {
 786                         s->s3->wbuf.left=0;
 787                         s->rwstate=SSL_NOTHING;
 788                         return(s->s3->wpend_ret);
 789                         }
 790                 else if (i <= 0) {
 791                         if (s->version == DTLS1_VERSION ||
 792                             s->version == DTLS1_BAD_VER) {
 793                                 /* For DTLS, just drop it. That's kind of the whole
 794                                    point in using a datagram service */
 795                                 s->s3->wbuf.left = 0;
 796                         }
 797                         return(i);
 798                 }
 799                 s->s3->wbuf.offset+=i;
 800                 s->s3->wbuf.left-=i;
 801                 }
 802         }
 803
 804 /* Return up to 'len' payload bytes received in 'type' records.
 805  * 'type' is one of the following:
 806  *
 807  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 808  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 809  *   -  0 (during a shutdown, no data has to be returned)
 810  *
 811  * If we don't have stored data to work from, read a SSL/TLS record first
 812  * (possibly multiple records if we still don't have anything to return).
 813  *
 814  * This function must handle any surprises the peer may have for us, such as
 815  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 816  * a surprise, but handled as if it were), or renegotiation requests.
 817  * Also if record payloads contain fragments too small to process, we store
 818  * them until there is enough for the respective protocol (the record protocol
 819  * may use arbitrary fragmentation and even interleaving):
 820  *     Change cipher spec protocol
 821  *             just 1 byte needed, no need for keeping anything stored
 822  *     Alert protocol
 823  *             2 bytes needed (AlertLevel, AlertDescription)
 824  *     Handshake protocol
 825  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 826  *             to detect unexpected Client Hello and Hello Request messages
 827  *             here, anything else is handled by higher layers
 828  *     Application data protocol
 829  *             none of our business
 830  */
 831 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 832         {
 833         int al,i,j,ret;
 834         unsigned int n;
 835         SSL3_RECORD *rr;
 836         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 837
 838         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 839                 if (!ssl3_setup_buffers(s))
 840                         return(-1);
 841
 842         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
 843             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 844                 {
 845                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
 846                 return -1;
 847                 }
 848
 849         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 850                 /* (partially) satisfy request from storage */
 851                 {
 852                 unsigned char *src = s->s3->handshake_fragment;
 853                 unsigned char *dst = buf;
 854                 unsigned int k;
 855
 856                 /* peek == 0 */
 857                 n = 0;
 858                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 859                         {
 860                         *dst++ = *src++;
 861                         len--; s->s3->handshake_fragment_len--;
 862                         n++;
 863                         }
 864                 /* move any remaining fragment bytes: */
 865                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
 866                         s->s3->handshake_fragment[k] = *src++;
 867                 return n;
 868         }
 869
 870         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 871
 872         if (!s->in_handshake && SSL_in_init(s))
 873                 {
 874                 /* type == SSL3_RT_APPLICATION_DATA */
 875                 i=s->handshake_func(s);
 876                 if (i < 0) return(i);
 877                 if (i == 0)
 878                         {
 879                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 880                         return(-1);
 881                         }
 882                 }
 883 start:
 884         s->rwstate=SSL_NOTHING;
 885
 886         /* s->s3->rrec.type         - is the type of record
 887          * s->s3->rrec.data,    - data
 888          * s->s3->rrec.off,     - offset into 'data' for next read
 889          * s->s3->rrec.length,  - number of bytes. */
 890         rr = &(s->s3->rrec);
 891
 892         /* get new packet if necessary */
 893         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 894                 {
 895                 ret=ssl3_get_record(s);
 896                 if (ret <= 0) return(ret);
 897                 }
 898
 899         /* we now have a packet which can be read and processed */
 900
 901         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 902                                        * reset by ssl3_get_finished */
 903                 && (rr->type != SSL3_RT_HANDSHAKE))
 904                 {
 905                 al=SSL_AD_UNEXPECTED_MESSAGE;
 906                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 907                 goto f_err;
 908                 }
 909
 910         /* If the other end has shut down, throw anything we read away
 911          * (even in 'peek' mode) */
 912         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 913                 {
 914                 rr->length=0;
 915                 s->rwstate=SSL_NOTHING;
 916                 return(0);
 917                 }
 918
 919
 920         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 921                 {
 922                 /* make sure that we are not getting application data when we
 923                  * are doing a handshake for the first time */
 924                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 925                         (s->enc_read_ctx == NULL))
 926                         {
 927                         al=SSL_AD_UNEXPECTED_MESSAGE;
 928                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 929                         goto f_err;
 930                         }
 931
 932                 if (len <= 0) return(len);
 933
 934                 if ((unsigned int)len > rr->length)
 935                         n = rr->length;
 936                 else
 937                         n = (unsigned int)len;
 938
 939                 memcpy(buf,&(rr->data[rr->off]),n);
 940                 if (!peek)
 941                         {
 942                         rr->length-=n;
 943                         rr->off+=n;
 944                         if (rr->length == 0)
 945                                 {
 946                                 s->rstate=SSL_ST_READ_HEADER;
 947                                 rr->off=0;
 948                                 }
 949                         }
 950                 return(n);
 951                 }
 952
 953
 954         /* If we get here, then type != rr->type; if we have a handshake
 955          * message, then it was unexpected (Hello Request or Client Hello). */
 956
 957         /* In case of record types for which we have 'fragment' storage,
 958          * fill that so that we can process the data at a fixed place.
 959          */
 960                 {
 961                 unsigned int dest_maxlen = 0;
 962                 unsigned char *dest = NULL;
 963                 unsigned int *dest_len = NULL;
 964
 965                 if (rr->type == SSL3_RT_HANDSHAKE)
 966                         {
 967                         dest_maxlen = sizeof s->s3->handshake_fragment;
 968                         dest = s->s3->handshake_fragment;
 969                         dest_len = &s->s3->handshake_fragment_len;
 970                         }
 971                 else if (rr->type == SSL3_RT_ALERT)
 972                         {
 973                         dest_maxlen = sizeof s->s3->alert_fragment;
 974                         dest = s->s3->alert_fragment;
 975                         dest_len = &s->s3->alert_fragment_len;
 976                         }
 977
 978                 if (dest_maxlen > 0)
 979                         {
 980                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
 981                         if (rr->length < n)
 982                                 n = rr->length; /* available bytes */
 983
 984                         /* now move 'n' bytes: */
 985                         while (n-- > 0)
 986                                 {
 987                                 dest[(*dest_len)++] = rr->data[rr->off++];
 988                                 rr->length--;
 989                                 }
 990
 991                         if (*dest_len < dest_maxlen)
 992                                 goto start; /* fragment was too small */
 993                         }
 994                 }
 995
 996         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
 997          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
 998          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
 999
1000         /* If we are a client, check for an incoming 'Hello Request': */
1001         if ((!s->server) &&
1002                 (s->s3->handshake_fragment_len >= 4) &&
1003                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1004                 (s->session != NULL) && (s->session->cipher != NULL))
1005                 {
1006                 s->s3->handshake_fragment_len = 0;
1007
1008                 if ((s->s3->handshake_fragment[1] != 0) ||
1009                         (s->s3->handshake_fragment[2] != 0) ||
1010                         (s->s3->handshake_fragment[3] != 0))
1011                         {
1012                         al=SSL_AD_DECODE_ERROR;
1013                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1014                         goto f_err;
1015                         }
1016
1017                 if (s->msg_callback)
1018                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1019
1020                 if (SSL_is_init_finished(s) &&
1021                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1022                         !s->s3->renegotiate)
1023                         {
1024                         ssl3_renegotiate(s);
1025                         if (ssl3_renegotiate_check(s))
1026                                 {
1027                                 i=s->handshake_func(s);
1028                                 if (i < 0) return(i);
1029                                 if (i == 0)
1030                                         {
1031                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1032                                         return(-1);
1033                                         }
1034
1035                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1036                                         {
1037                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1038                                                 {
1039                                                 BIO *bio;
1040                                                 /* In the case where we try to read application data,
1041                                                  * but we trigger an SSL handshake, we return -1 with
1042                                                  * the retry option set.  Otherwise renegotiation may
1043                                                  * cause nasty problems in the blocking world */
1044                                                 s->rwstate=SSL_READING;
1045                                                 bio=SSL_get_rbio(s);
1046                                                 BIO_clear_retry_flags(bio);
1047                                                 BIO_set_retry_read(bio);
1048                                                 return(-1);
1049                                                 }
1050                                         }
1051                                 }
1052                         }
1053                 /* we either finished a handshake or ignored the request,
1054                  * now try again to obtain the (application) data we were asked for */
1055                 goto start;
1056                 }
1057         /* If we are a server and get a client hello when renegotiation isn't
1058          * allowed send back a no renegotiation alert and carry on.
1059          * WARNING: experimental code, needs reviewing (steve)
1060          */
1061         if (s->server &&
1062                 SSL_is_init_finished(s) &&
1063                 !s->s3->send_connection_binding &&
1064                 (s->version > SSL3_VERSION) &&
1065                 (s->s3->handshake_fragment_len >= 4) &&
1066                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1067                 (s->session != NULL) && (s->session->cipher != NULL) &&
1068                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1069
1070                 {
1071                 /*s->s3->handshake_fragment_len = 0;*/
1072                 rr->length = 0;
1073                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1074                 goto start;
1075                 }
1076         if (s->s3->alert_fragment_len >= 2)
1077                 {
1078                 int alert_level = s->s3->alert_fragment[0];
1079                 int alert_descr = s->s3->alert_fragment[1];
1080
1081                 s->s3->alert_fragment_len = 0;
1082
1083                 if (s->msg_callback)
1084                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1085
1086                 if (s->info_callback != NULL)
1087                         cb=s->info_callback;
1088                 else if (s->ctx->info_callback != NULL)
1089                         cb=s->ctx->info_callback;
1090
1091                 if (cb != NULL)
1092                         {
1093                         j = (alert_level << 8) | alert_descr;
1094                         cb(s, SSL_CB_READ_ALERT, j);
1095                         }
1096
1097                 if (alert_level == 1) /* warning */
1098                         {
1099                         s->s3->warn_alert = alert_descr;
1100                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1101                                 {
1102                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1103                                 return(0);
1104                                 }
1105                         /* This is a warning but we receive it if we requested
1106                          * renegotiation and the peer denied it. Terminate with
1107                          * a fatal alert because if application tried to
1108                          * renegotiatie it presumably had a good reason and
1109                          * expects it to succeed.
1110                          *
1111                          * In future we might have a renegotiation where we
1112                          * don't care if the peer refused it where we carry on.
1113                          */
1114                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1115                                 {
1116                                 al = SSL_AD_HANDSHAKE_FAILURE;
1117                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1118                                 goto f_err;
1119                                 }
1120                         }
1121                 else if (alert_level == 2) /* fatal */
1122                         {
1123                         char tmp[16];
1124
1125                         s->rwstate=SSL_NOTHING;
1126                         s->s3->fatal_alert = alert_descr;
1127                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1128                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1129                         ERR_add_error_data(2,"SSL alert number ",tmp);
1130                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1131                         SSL_CTX_remove_session(s->ctx,s->session);
1132                         return(0);
1133                         }
1134                 else
1135                         {
1136                         al=SSL_AD_ILLEGAL_PARAMETER;
1137                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1138                         goto f_err;
1139                         }
1140
1141                 goto start;
1142                 }
1143
1144         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1145                 {
1146                 s->rwstate=SSL_NOTHING;
1147                 rr->length=0;
1148                 return(0);
1149                 }
1150
1151         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1152                 {
1153                 /* 'Change Cipher Spec' is just a single byte, so we know
1154                  * exactly what the record payload has to look like */
1155                 if (    (rr->length != 1) || (rr->off != 0) ||
1156                         (rr->data[0] != SSL3_MT_CCS))
1157                         {
1158                         al=SSL_AD_ILLEGAL_PARAMETER;
1159                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1160                         goto f_err;
1161                         }
1162
1163                 /* Check we have a cipher to change to */
1164                 if (s->s3->tmp.new_cipher == NULL)
1165                         {
1166                         al=SSL_AD_UNEXPECTED_MESSAGE;
1167                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1168                         goto f_err;
1169                         }
1170
1171                 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1172                         {
1173                         al=SSL_AD_UNEXPECTED_MESSAGE;
1174                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1175                         goto f_err;
1176                         }
1177
1178                 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1179
1180                 rr->length=0;
1181
1182                 if (s->msg_callback)
1183                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1184
1185                 s->s3->change_cipher_spec=1;
1186                 if (!ssl3_do_change_cipher_spec(s))
1187                         goto err;
1188                 else
1189                         goto start;
1190                 }
1191
1192         /* Unexpected handshake message (Client Hello, or protocol violation) */
1193         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1194                 {
1195                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1196                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1197                         {
1198 #if 0 /* worked only because C operator preferences are not as expected (and
1199        * because this is not really needed for clients except for detecting
1200        * protocol violations): */
1201                         s->state=SSL_ST_BEFORE|(s->server)
1202                                 ?SSL_ST_ACCEPT
1203                                 :SSL_ST_CONNECT;
1204 #else
1205                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1206 #endif
1207                         s->new_session=1;
1208                         }
1209                 i=s->handshake_func(s);
1210                 if (i < 0) return(i);
1211                 if (i == 0)
1212                         {
1213                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1214                         return(-1);
1215                         }
1216
1217                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1218                         {
1219                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1220                                 {
1221                                 BIO *bio;
1222                                 /* In the case where we try to read application data,
1223                                  * but we trigger an SSL handshake, we return -1 with
1224                                  * the retry option set.  Otherwise renegotiation may
1225                                  * cause nasty problems in the blocking world */
1226                                 s->rwstate=SSL_READING;
1227                                 bio=SSL_get_rbio(s);
1228                                 BIO_clear_retry_flags(bio);
1229                                 BIO_set_retry_read(bio);
1230                                 return(-1);
1231                                 }
1232                         }
1233                 goto start;
1234                 }
1235
1236         switch (rr->type)
1237                 {
1238         default:
1239 #ifndef OPENSSL_NO_TLS
1240                 /* TLS just ignores unknown message types */
1241                 if (s->version == TLS1_VERSION)
1242                         {
1243                         rr->length = 0;
1244                         goto start;
1245                         }
1246 #endif
1247                 al=SSL_AD_UNEXPECTED_MESSAGE;
1248                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1249                 goto f_err;
1250         case SSL3_RT_CHANGE_CIPHER_SPEC:
1251         case SSL3_RT_ALERT:
1252         case SSL3_RT_HANDSHAKE:
1253                 /* we already handled all of these, with the possible exception
1254                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1255                  * should not happen when type != rr->type */
1256                 al=SSL_AD_UNEXPECTED_MESSAGE;
1257                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1258                 goto f_err;
1259         case SSL3_RT_APPLICATION_DATA:
1260                 /* At this point, we were expecting handshake data,
1261                  * but have application data.  If the library was
1262                  * running inside ssl3_read() (i.e. in_read_app_data
1263                  * is set) and it makes sense to read application data
1264                  * at this point (session renegotiation not yet started),
1265                  * we will indulge it.
1266                  */
1267                 if (s->s3->in_read_app_data &&
1268                         (s->s3->total_renegotiations != 0) &&
1269                         ((
1270                                 (s->state & SSL_ST_CONNECT) &&
1271                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1272                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1273                                 ) || (
1274                                         (s->state & SSL_ST_ACCEPT) &&
1275                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1276                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1277                                         )
1278                                 ))
1279                         {
1280                         s->s3->in_read_app_data=2;
1281                         return(-1);
1282                         }
1283                 else
1284                         {
1285                         al=SSL_AD_UNEXPECTED_MESSAGE;
1286                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1287                         goto f_err;
1288                         }
1289                 }
1290         /* not reached */
1291
1292 f_err:
1293         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1294 err:
1295         return(-1);
1296         }
1297
1298 int ssl3_do_change_cipher_spec(SSL *s)
1299         {
1300         int i;
1301         const char *sender;
1302         int slen;
1303
1304         if (s->state & SSL_ST_ACCEPT)
1305                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1306         else
1307                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1308
1309         if (s->s3->tmp.key_block == NULL)
1310                 {
1311                 if (s->session == NULL || s->session->master_key_length == 0)
1312                         {
1313                         /* might happen if dtls1_read_bytes() calls this */
1314                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1315                         return (0);
1316                         }
1317
1318                 s->session->cipher=s->s3->tmp.new_cipher;
1319                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1320                 }
1321
1322         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1323                 return(0);
1324
1325         /* we have to record the message digest at
1326          * this point so we can get it before we read
1327          * the finished message */
1328         if (s->state & SSL_ST_CONNECT)
1329                 {
1330                 sender=s->method->ssl3_enc->server_finished_label;
1331                 slen=s->method->ssl3_enc->server_finished_label_len;
1332                 }
1333         else
1334                 {
1335                 sender=s->method->ssl3_enc->client_finished_label;
1336                 slen=s->method->ssl3_enc->client_finished_label_len;
1337                 }
1338
1339         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1340                 &(s->s3->finish_dgst1),
1341                 &(s->s3->finish_dgst2),
1342                 sender,slen,s->s3->tmp.peer_finish_md);
1343
1344         return(1);
1345         }
1346
1347 int ssl3_send_alert(SSL *s, int level, int desc)
1348         {
1349         /* Map tls/ssl alert value to correct one */
1350         desc=s->method->ssl3_enc->alert_value(desc);
1351         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1352                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1353         if (desc < 0) return -1;
1354         /* If a fatal one, remove from cache */
1355         if ((level == 2) && (s->session != NULL))
1356                 SSL_CTX_remove_session(s->ctx,s->session);
1357
1358         s->s3->alert_dispatch=1;
1359         s->s3->send_alert[0]=level;
1360         s->s3->send_alert[1]=desc;
1361         if (s->s3->wbuf.left == 0) /* data still being written out? */
1362                 return s->method->ssl_dispatch_alert(s);
1363         /* else data is still being written out, we will get written
1364          * some time in the future */
1365         return -1;
1366         }
1367
1368 int ssl3_dispatch_alert(SSL *s)
1369         {
1370         int i,j;
1371         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1372
1373         s->s3->alert_dispatch=0;
1374         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1375         if (i <= 0)
1376                 {
1377                 s->s3->alert_dispatch=1;
1378                 }
1379         else
1380                 {
1381                 /* Alert sent to BIO.  If it is important, flush it now.
1382                  * If the message does not get sent due to non-blocking IO,
1383                  * we will not worry too much. */
1384                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1385                         (void)BIO_flush(s->wbio);
1386
1387                 if (s->msg_callback)
1388                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1389
1390                 if (s->info_callback != NULL)
1391                         cb=s->info_callback;
1392                 else if (s->ctx->info_callback != NULL)
1393                         cb=s->ctx->info_callback;
1394
1395                 if (cb != NULL)
1396                         {
1397                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1398                         cb(s,SSL_CB_WRITE_ALERT,j);
1399                         }
1400                 }
1401         return(i);
1402         }