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 #include <openssl/rand.h>
 120
 121 #ifndef  EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
 122 # define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0
 123 #endif
 124
 125 #if     defined(OPENSSL_SMALL_FOOTPRINT) || \
 126         !(      defined(AES_ASM) &&     ( \
 127                 defined(__x86_64)       || defined(__x86_64__)  || \
 128                 defined(_M_AMD64)       || defined(_M_X64)      || \
 129                 defined(__INTEL__)      ) \
 130         )
 131 # undef EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
 132 # define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0
 133 #endif
 134
 135 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 136                          unsigned int len, int create_empty_fragment);
 137 static int ssl3_get_record(SSL *s);
 138
 139 int ssl3_read_n(SSL *s, int n, int max, int extend)
 140         {
 141         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
 142          * packet by another n bytes.
 143          * The packet will be in the sub-array of s->s3->rbuf.buf specified
 144          * by s->packet and s->packet_length.
 145          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
 146          * [plus s->packet_length bytes if extend == 1].)
 147          */
 148         int i,len,left;
 149         long align=0;
 150         unsigned char *pkt;
 151         SSL3_BUFFER *rb;
 152
 153         if (n <= 0) return n;
 154
 155         rb    = &(s->s3->rbuf);
 156         if (rb->buf == NULL)
 157                 if (!ssl3_setup_read_buffer(s))
 158                         return -1;
 159
 160         left  = rb->left;
 161 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
 162         align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
 163         align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
 164 #endif
 165
 166         if (!extend)
 167                 {
 168                 /* start with empty packet ... */
 169                 if (left == 0)
 170                         rb->offset = align;
 171                 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
 172                         {
 173                         /* check if next packet length is large
 174                          * enough to justify payload alignment... */
 175                         pkt = rb->buf + rb->offset;
 176                         if (pkt[0] == SSL3_RT_APPLICATION_DATA
 177                             && (pkt[3]<<8|pkt[4]) >= 128)
 178                                 {
 179                                 /* Note that even if packet is corrupted
 180                                  * and its length field is insane, we can
 181                                  * only be led to wrong decision about
 182                                  * whether memmove will occur or not.
 183                                  * Header values has no effect on memmove
 184                                  * arguments and therefore no buffer
 185                                  * overrun can be triggered. */
 186                                 memmove (rb->buf+align,pkt,left);
 187                                 rb->offset = align;
 188                                 }
 189                         }
 190                 s->packet = rb->buf + rb->offset;
 191                 s->packet_length = 0;
 192                 /* ... now we can act as if 'extend' was set */
 193                 }
 194
 195         /* For DTLS/UDP reads should not span multiple packets
 196          * because the read operation returns the whole packet
 197          * at once (as long as it fits into the buffer). */
 198         if (SSL_IS_DTLS(s))
 199                 {
 200                 if (left > 0 && n > left)
 201                         n = left;
 202                 }
 203
 204         /* if there is enough in the buffer from a previous read, take some */
 205         if (left >= n)
 206                 {
 207                 s->packet_length+=n;
 208                 rb->left=left-n;
 209                 rb->offset+=n;
 210                 return(n);
 211                 }
 212
 213         /* else we need to read more data */
 214
 215         len = s->packet_length;
 216         pkt = rb->buf+align;
 217         /* Move any available bytes to front of buffer:
 218          * 'len' bytes already pointed to by 'packet',
 219          * 'left' extra ones at the end */
 220         if (s->packet != pkt) /* len > 0 */
 221                 {
 222                 memmove(pkt, s->packet, len+left);
 223                 s->packet = pkt;
 224                 rb->offset = len + align;
 225                 }
 226
 227         if (n > (int)(rb->len - rb->offset)) /* does not happen */
 228                 {
 229                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 230                 return -1;
 231                 }
 232
 233         if (!s->read_ahead)
 234                 /* ignore max parameter */
 235                 max = n;
 236         else
 237                 {
 238                 if (max < n)
 239                         max = n;
 240                 if (max > (int)(rb->len - rb->offset))
 241                         max = rb->len - rb->offset;
 242                 }
 243
 244         while (left < n)
 245                 {
 246                 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
 247                  * and need to read in more until we have len+n (up to
 248                  * len+max if possible) */
 249
 250                 clear_sys_error();
 251                 if (s->rbio != NULL)
 252                         {
 253                         s->rwstate=SSL_READING;
 254                         i=BIO_read(s->rbio,pkt+len+left, max-left);
 255                         }
 256                 else
 257                         {
 258                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 259                         i = -1;
 260                         }
 261
 262                 if (i <= 0)
 263                         {
 264                         rb->left = left;
 265                         if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
 266                                 !SSL_IS_DTLS(s))
 267                                 if (len+left == 0)
 268                                         ssl3_release_read_buffer(s);
 269                         return(i);
 270                         }
 271                 left+=i;
 272                 /* reads should *never* span multiple packets for DTLS because
 273                  * the underlying transport protocol is message oriented as opposed
 274                  * to byte oriented as in the TLS case. */
 275                 if (SSL_IS_DTLS(s))
 276                         {
 277                         if (n > left)
 278                                 n = left; /* makes the while condition false */
 279                         }
 280                 }
 281
 282         /* done reading, now the book-keeping */
 283         rb->offset += n;
 284         rb->left = left - n;
 285         s->packet_length += n;
 286         s->rwstate=SSL_NOTHING;
 287         return(n);
 288         }
 289
 290 /* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will
 291  * be processed per call to ssl3_get_record. Without this limit an attacker
 292  * could send empty records at a faster rate than we can process and cause
 293  * ssl3_get_record to loop forever. */
 294 #define MAX_EMPTY_RECORDS 32
 295
 296 /* Call this to get a new input record.
 297  * It will return <= 0 if more data is needed, normally due to an error
 298  * or non-blocking IO.
 299  * When it finishes, one packet has been decoded and can be found in
 300  * ssl->s3->rrec.type    - is the type of record
 301  * ssl->s3->rrec.data,   - data
 302  * ssl->s3->rrec.length, - number of bytes
 303  */
 304 /* used only by ssl3_read_bytes */
 305 static int ssl3_get_record(SSL *s)
 306         {
 307         int ssl_major,ssl_minor,al;
 308         int enc_err,n,i,ret= -1;
 309         SSL3_RECORD *rr;
 310         SSL_SESSION *sess;
 311         unsigned char *p;
 312         unsigned char md[EVP_MAX_MD_SIZE];
 313         short version;
 314         unsigned mac_size, orig_len;
 315         size_t extra;
 316         unsigned empty_record_count = 0;
 317
 318         rr= &(s->s3->rrec);
 319         sess=s->session;
 320
 321         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 322                 extra=SSL3_RT_MAX_EXTRA;
 323         else
 324                 extra=0;
 325         if (extra && !s->s3->init_extra)
 326                 {
 327                 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
 328                  * set after ssl3_setup_buffers() was done */
 329                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
 330                 return -1;
 331                 }
 332
 333 again:
 334         /* check if we have the header */
 335         if (    (s->rstate != SSL_ST_READ_BODY) ||
 336                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 337                 {
 338                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 339                 if (n <= 0) return(n); /* error or non-blocking */
 340                 s->rstate=SSL_ST_READ_BODY;
 341
 342                 p=s->packet;
 343                 if (s->msg_callback)
 344                         s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s, s->msg_callback_arg);
 345
 346                 /* Pull apart the header into the SSL3_RECORD */
 347                 rr->type= *(p++);
 348                 ssl_major= *(p++);
 349                 ssl_minor= *(p++);
 350                 version=(ssl_major<<8)|ssl_minor;
 351                 n2s(p,rr->length);
 352 #if 0
 353 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
 354 #endif
 355
 356                 /* Lets check version */
 357                 if (!s->first_packet)
 358                         {
 359                         if (version != s->version)
 360                                 {
 361                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 362                                 if ((s->version & 0xFF00) == (version & 0xFF00) && !s->enc_write_ctx && !s->write_hash)
 363                                         /* Send back error using their minor version number :-) */
 364                                         s->version = (unsigned short)version;
 365                                 al=SSL_AD_PROTOCOL_VERSION;
 366                                 goto f_err;
 367                                 }
 368                         }
 369
 370                 if ((version>>8) != SSL3_VERSION_MAJOR)
 371                         {
 372                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 373                         goto err;
 374                         }
 375
 376                 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
 377                         {
 378                         al=SSL_AD_RECORD_OVERFLOW;
 379                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 380                         goto f_err;
 381                         }
 382
 383                 /* now s->rstate == SSL_ST_READ_BODY */
 384                 }
 385
 386         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 387
 388         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
 389                 {
 390                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
 391                 i=rr->length;
 392                 n=ssl3_read_n(s,i,i,1);
 393                 if (n <= 0) return(n); /* error or non-blocking io */
 394                 /* now n == rr->length,
 395                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
 396                 }
 397
 398         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 399
 400         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 401          * and we have that many bytes in s->packet
 402          */
 403         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 404
 405         /* ok, we can now read from 's->packet' data into 'rr'
 406          * rr->input points at rr->length bytes, which
 407          * need to be copied into rr->data by either
 408          * the decryption or by the decompression
 409          * When the data is 'copied' into the rr->data buffer,
 410          * rr->input will be pointed at the new buffer */
 411
 412         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 413          * rr->length bytes of encrypted compressed stuff. */
 414
 415         /* check is not needed I believe */
 416         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 417                 {
 418                 al=SSL_AD_RECORD_OVERFLOW;
 419                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 420                 goto f_err;
 421                 }
 422
 423         /* decrypt in place in 'rr->input' */
 424         rr->data=rr->input;
 425
 426         enc_err = s->method->ssl3_enc->enc(s,0);
 427         /* enc_err is:
 428          *    0: (in non-constant time) if the record is publically invalid.
 429          *    1: if the padding is valid
 430          *    -1: if the padding is invalid */
 431         if (enc_err == 0)
 432                 {
 433                 al=SSL_AD_DECRYPTION_FAILED;
 434                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
 435                 goto f_err;
 436                 }
 437
 438 #ifdef TLS_DEBUG
 439 printf("dec %d\n",rr->length);
 440 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 441 printf("\n");
 442 #endif
 443
 444         /* r->length is now the compressed data plus mac */
 445         if ((sess != NULL) &&
 446             (s->enc_read_ctx != NULL) &&
 447             (EVP_MD_CTX_md(s->read_hash) != NULL))
 448                 {
 449                 /* s->read_hash != NULL => mac_size != -1 */
 450                 unsigned char *mac = NULL;
 451                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 452                 mac_size=EVP_MD_CTX_size(s->read_hash);
 453                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 454
 455                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 456                 orig_len = rr->length+((unsigned int)rr->type>>8);
 457
 458                 /* orig_len is the length of the record before any padding was
 459                  * removed. This is public information, as is the MAC in use,
 460                  * therefore we can safely process the record in a different
 461                  * amount of time if it's too short to possibly contain a MAC.
 462                  */
 463                 if (orig_len < mac_size ||
 464                     /* CBC records must have a padding length byte too. */
 465                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 466                      orig_len < mac_size+1))
 467                         {
 468                         al=SSL_AD_DECODE_ERROR;
 469                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 470                         goto f_err;
 471                         }
 472
 473                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 474                         {
 475                         /* We update the length so that the TLS header bytes
 476                          * can be constructed correctly but we need to extract
 477                          * the MAC in constant time from within the record,
 478                          * without leaking the contents of the padding bytes.
 479                          * */
 480                         mac = mac_tmp;
 481                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 482                         rr->length -= mac_size;
 483                         }
 484                 else
 485                         {
 486                         /* In this case there's no padding, so |orig_len|
 487                          * equals |rec->length| and we checked that there's
 488                          * enough bytes for |mac_size| above. */
 489                         rr->length -= mac_size;
 490                         mac = &rr->data[rr->length];
 491                         }
 492
 493                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 494                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 495                         enc_err = -1;
 496                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 497                         enc_err = -1;
 498                 }
 499
 500         if (enc_err < 0)
 501                 {
 502                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
 503                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
 504                  * failure is directly visible from the ciphertext anyway,
 505                  * we should not reveal which kind of error occured -- this
 506                  * might become visible to an attacker (e.g. via a logfile) */
 507                 al=SSL_AD_BAD_RECORD_MAC;
 508                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
 509                 goto f_err;
 510                 }
 511
 512         /* r->length is now just compressed */
 513         if (s->expand != NULL)
 514                 {
 515                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 516                         {
 517                         al=SSL_AD_RECORD_OVERFLOW;
 518                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 519                         goto f_err;
 520                         }
 521                 if (!ssl3_do_uncompress(s))
 522                         {
 523                         al=SSL_AD_DECOMPRESSION_FAILURE;
 524                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 525                         goto f_err;
 526                         }
 527                 }
 528
 529         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
 530                 {
 531                 al=SSL_AD_RECORD_OVERFLOW;
 532                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 533                 goto f_err;
 534                 }
 535
 536         rr->off=0;
 537         /* So at this point the following is true
 538          * ssl->s3->rrec.type   is the type of record
 539          * ssl->s3->rrec.length == number of bytes in record
 540          * ssl->s3->rrec.off    == offset to first valid byte
 541          * ssl->s3->rrec.data   == where to take bytes from, increment
 542          *                         after use :-).
 543          */
 544
 545         /* we have pulled in a full packet so zero things */
 546         s->packet_length=0;
 547
 548         /* just read a 0 length packet */
 549         if (rr->length == 0)
 550                 {
 551                 empty_record_count++;
 552                 if (empty_record_count > MAX_EMPTY_RECORDS)
 553                         {
 554                         al=SSL_AD_UNEXPECTED_MESSAGE;
 555                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL);
 556                         goto f_err;
 557                         }
 558                 goto again;
 559                 }
 560
 561 #if 0
 562 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
 563 #endif
 564
 565         return(1);
 566
 567 f_err:
 568         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 569 err:
 570         return(ret);
 571         }
 572
 573 int ssl3_do_uncompress(SSL *ssl)
 574         {
 575 #ifndef OPENSSL_NO_COMP
 576         int i;
 577         SSL3_RECORD *rr;
 578
 579         rr= &(ssl->s3->rrec);
 580         i=COMP_expand_block(ssl->expand,rr->comp,
 581                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 582         if (i < 0)
 583                 return(0);
 584         else
 585                 rr->length=i;
 586         rr->data=rr->comp;
 587 #endif
 588         return(1);
 589         }
 590
 591 int ssl3_do_compress(SSL *ssl)
 592         {
 593 #ifndef OPENSSL_NO_COMP
 594         int i;
 595         SSL3_RECORD *wr;
 596
 597         wr= &(ssl->s3->wrec);
 598         i=COMP_compress_block(ssl->compress,wr->data,
 599                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 600                 wr->input,(int)wr->length);
 601         if (i < 0)
 602                 return(0);
 603         else
 604                 wr->length=i;
 605
 606         wr->input=wr->data;
 607 #endif
 608         return(1);
 609         }
 610
 611 /* Call this to write data in records of type 'type'
 612  * It will return <= 0 if not all data has been sent or non-blocking IO.
 613  */
 614 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 615         {
 616         const unsigned char *buf=buf_;
 617         int tot;
 618         unsigned int n,nw;
 619 #if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
 620         unsigned int max_send_fragment;
 621 #endif
 622         SSL3_BUFFER *wb=&(s->s3->wbuf);
 623         int i;
 624
 625         s->rwstate=SSL_NOTHING;
 626         OPENSSL_assert(s->s3->wnum <= INT_MAX);
 627         tot=s->s3->wnum;
 628         s->s3->wnum=0;
 629
 630         if (SSL_in_init(s) && !s->in_handshake)
 631                 {
 632                 i=s->handshake_func(s);
 633                 if (i < 0) return(i);
 634                 if (i == 0)
 635                         {
 636                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 637                         return -1;
 638                         }
 639                 }
 640
 641         /* ensure that if we end up with a smaller value of data to write
 642          * out than the the original len from a write which didn't complete
 643          * for non-blocking I/O and also somehow ended up avoiding
 644          * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
 645          * it must never be possible to end up with (len-tot) as a large
 646          * number that will then promptly send beyond the end of the users
 647          * buffer ... so we trap and report the error in a way the user
 648          * will notice
 649          */
 650         if (len < tot)
 651                 {
 652                 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
 653                 return(-1);
 654                 }
 655
 656         /* first check if there is a SSL3_BUFFER still being written
 657          * out.  This will happen with non blocking IO */
 658         if (wb->left != 0)
 659                 {
 660                 i = ssl3_write_pending(s,type,&buf[tot],s->s3->wpend_tot);
 661                 if (i<=0)
 662                         {
 663                         /* XXX should we ssl3_release_write_buffer if i<0? */
 664                         s->s3->wnum=tot;
 665                         return i;
 666                         }
 667                 tot += i;       /* this might be last fragment */
 668                 }
 669
 670 #if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
 671         /*
 672          * Depending on platform multi-block can deliver several *times*
 673          * better performance. Downside is that it has to allocate
 674          * jumbo buffer to accomodate up to 8 records, but the
 675          * compromise is considered worthy.
 676          */
 677         if (type==SSL3_RT_APPLICATION_DATA &&
 678             len >= 4*(int)(max_send_fragment=s->max_send_fragment) &&
 679             s->compress==NULL && s->msg_callback==NULL &&
 680             SSL_USE_EXPLICIT_IV(s) &&
 681             EVP_CIPHER_flags(s->enc_write_ctx->cipher)&EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK)
 682                 {
 683                 unsigned char aad[13];
 684                 EVP_CTRL_TLS1_1_MULTIBLOCK_PARAM mb_param;
 685                 int packlen;
 686
 687                 /* minimize address aliasing conflicts */
 688                 if ((max_send_fragment&0xfff) == 0)
 689                         max_send_fragment -= 512;
 690
 691                 if (tot==0 || wb->buf==NULL)    /* allocate jumbo buffer */
 692                         {
 693                         ssl3_release_write_buffer(s);
 694
 695                         packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
 696                                         EVP_CTRL_TLS1_1_MULTIBLOCK_MAX_BUFSIZE,
 697                                         max_send_fragment,NULL);
 698
 699                         if (len>=8*(int)max_send_fragment)      packlen *= 8;
 700                         else                            packlen *= 4;
 701
 702                         wb->buf=OPENSSL_malloc(packlen);
 703                         wb->len=packlen;
 704                         }
 705                 else if (tot==len)              /* done? */
 706                         {
 707                         OPENSSL_free(wb->buf);  /* free jumbo buffer */
 708                         wb->buf = NULL;
 709                         return tot;
 710                         }
 711
 712                 n=(len-tot);
 713                 for (;;)
 714                         {
 715                         if (n < 4*max_send_fragment)
 716                                 {
 717                                 OPENSSL_free(wb->buf);  /* free jumbo buffer */
 718                                 wb->buf = NULL;
 719                                 break;
 720                                 }
 721
 722                         if (s->s3->alert_dispatch)
 723                                 {
 724                                 i=s->method->ssl_dispatch_alert(s);
 725                                 if (i <= 0)
 726                                         {
 727                                         s->s3->wnum=tot;
 728                                         return i;
 729                                         }
 730                                 }
 731
 732                         if (n >= 8*max_send_fragment)
 733                                 nw = max_send_fragment*(mb_param.interleave=8);
 734                         else
 735                                 nw = max_send_fragment*(mb_param.interleave=4);
 736
 737                         memcpy(aad,s->s3->write_sequence,8);
 738                         aad[8]=type;
 739                         aad[9]=(unsigned char)(s->version>>8);
 740                         aad[10]=(unsigned char)(s->version);
 741                         aad[11]=0;
 742                         aad[12]=0;
 743                         mb_param.out = NULL;
 744                         mb_param.inp = aad;
 745                         mb_param.len = nw;
 746
 747                         packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
 748                                         EVP_CTRL_TLS1_1_MULTIBLOCK_AAD,
 749                                         sizeof(mb_param),&mb_param);
 750
 751                         if (packlen<=0 || packlen>(int)wb->len) /* never happens */
 752                                 {
 753                                 OPENSSL_free(wb->buf);  /* free jumbo buffer */
 754                                 wb->buf = NULL;
 755                                 break;
 756                                 }
 757
 758                         mb_param.out = wb->buf;
 759                         mb_param.inp = &buf[tot];
 760                         mb_param.len = nw;
 761
 762                         if (EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
 763                                         EVP_CTRL_TLS1_1_MULTIBLOCK_ENCRYPT,
 764                                         sizeof(mb_param),&mb_param)<=0)
 765                                 return -1;
 766
 767                         s->s3->write_sequence[7] += mb_param.interleave;
 768                         if (s->s3->write_sequence[7] < mb_param.interleave)
 769                                 {
 770                                 int j=6;
 771                                 while (j>=0 && (++s->s3->write_sequence[j--])==0) ;
 772                                 }
 773
 774                         wb->offset = 0;
 775                         wb->left = packlen;
 776
 777                         s->s3->wpend_tot = nw;
 778                         s->s3->wpend_buf = &buf[tot];
 779                         s->s3->wpend_type= type;
 780                         s->s3->wpend_ret = nw;
 781
 782                         i = ssl3_write_pending(s,type,&buf[tot],nw);
 783                         if (i<=0)
 784                                 {
 785                                 if (i<0)
 786                                         {
 787                                         OPENSSL_free(wb->buf);
 788                                         wb->buf = NULL;
 789                                         }
 790                                 s->s3->wnum=tot;
 791                                 return i;
 792                                 }
 793                         if (i==(int)n)
 794                                 {
 795                                 OPENSSL_free(wb->buf);  /* free jumbo buffer */
 796                                 wb->buf = NULL;
 797                                 return tot+i;
 798                                 }
 799                         n-=i;
 800                         tot+=i;
 801                         }
 802                 }
 803         else
 804 #endif
 805         if (tot==len)           /* done? */
 806                 {
 807                 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
 808                         !SSL_IS_DTLS(s))
 809                         ssl3_release_write_buffer(s);
 810
 811                 return tot;
 812                 }
 813
 814
 815         n=(len-tot);
 816         for (;;)
 817                 {
 818                 if (n > s->max_send_fragment)
 819                         nw=s->max_send_fragment;
 820                 else
 821                         nw=n;
 822
 823                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
 824                 if (i <= 0)
 825                         {
 826                         /* XXX should we ssl3_release_write_buffer if i<0? */
 827                         s->s3->wnum=tot;
 828                         return i;
 829                         }
 830
 831                 if ((i == (int)n) ||
 832                         (type == SSL3_RT_APPLICATION_DATA &&
 833                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 834                         {
 835                         /* next chunk of data should get another prepended empty fragment
 836                          * in ciphersuites with known-IV weakness: */
 837                         s->s3->empty_fragment_done = 0;
 838
 839                         if ((i==(int)n) && s->mode & SSL_MODE_RELEASE_BUFFERS &&
 840                                 !SSL_IS_DTLS(s))
 841                                 ssl3_release_write_buffer(s);
 842
 843                         return tot+i;
 844                         }
 845
 846                 n-=i;
 847                 tot+=i;
 848                 }
 849         }
 850
 851 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 852                          unsigned int len, int create_empty_fragment)
 853         {
 854         unsigned char *p,*plen;
 855         int i,mac_size,clear=0;
 856         int prefix_len=0;
 857         int eivlen;
 858         long align=0;
 859         SSL3_RECORD *wr;
 860         SSL3_BUFFER *wb=&(s->s3->wbuf);
 861         SSL_SESSION *sess;
 862
 863
 864         /* first check if there is a SSL3_BUFFER still being written
 865          * out.  This will happen with non blocking IO */
 866         if (wb->left != 0)
 867                 return(ssl3_write_pending(s,type,buf,len));
 868
 869         /* If we have an alert to send, lets send it */
 870         if (s->s3->alert_dispatch)
 871                 {
 872                 i=s->method->ssl_dispatch_alert(s);
 873                 if (i <= 0)
 874                         return(i);
 875                 /* if it went, fall through and send more stuff */
 876                 }
 877
 878         if (wb->buf == NULL)
 879                 if (!ssl3_setup_write_buffer(s))
 880                         return -1;
 881
 882         if (len == 0 && !create_empty_fragment)
 883                 return 0;
 884
 885         wr= &(s->s3->wrec);
 886         sess=s->session;
 887
 888         if (    (sess == NULL) ||
 889                 (s->enc_write_ctx == NULL) ||
 890                 (EVP_MD_CTX_md(s->write_hash) == NULL))
 891                 {
 892 #if 1
 893                 clear=s->enc_write_ctx?0:1;     /* must be AEAD cipher */
 894 #else
 895                 clear=1;
 896 #endif
 897                 mac_size=0;
 898                 }
 899         else
 900                 {
 901                 mac_size=EVP_MD_CTX_size(s->write_hash);
 902                 if (mac_size < 0)
 903                         goto err;
 904                 }
 905
 906         /* 'create_empty_fragment' is true only when this function calls itself */
 907         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
 908                 {
 909                 /* countermeasure against known-IV weakness in CBC ciphersuites
 910                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
 911
 912                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
 913                         {
 914                         /* recursive function call with 'create_empty_fragment' set;
 915                          * this prepares and buffers the data for an empty fragment
 916                          * (these 'prefix_len' bytes are sent out later
 917                          * together with the actual payload) */
 918                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
 919                         if (prefix_len <= 0)
 920                                 goto err;
 921
 922                         if (prefix_len >
 923                 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
 924                                 {
 925                                 /* insufficient space */
 926                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
 927                                 goto err;
 928                                 }
 929                         }
 930
 931                 s->s3->empty_fragment_done = 1;
 932                 }
 933
 934         if (create_empty_fragment)
 935                 {
 936 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
 937                 /* extra fragment would be couple of cipher blocks,
 938                  * which would be multiple of SSL3_ALIGN_PAYLOAD, so
 939                  * if we want to align the real payload, then we can
 940                  * just pretent we simply have two headers. */
 941                 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
 942                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
 943 #endif
 944                 p = wb->buf + align;
 945                 wb->offset  = align;
 946                 }
 947         else if (prefix_len)
 948                 {
 949                 p = wb->buf + wb->offset + prefix_len;
 950                 }
 951         else
 952                 {
 953 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
 954                 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
 955                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
 956 #endif
 957                 p = wb->buf + align;
 958                 wb->offset  = align;
 959                 }
 960
 961         /* write the header */
 962
 963         *(p++)=type&0xff;
 964         wr->type=type;
 965
 966         *(p++)=(s->version>>8);
 967         /* Some servers hang if iniatial client hello is larger than 256
 968          * bytes and record version number > TLS 1.0
 969          */
 970         if (s->state == SSL3_ST_CW_CLNT_HELLO_B
 971                                 && !s->renegotiate
 972                                 && TLS1_get_version(s) > TLS1_VERSION)
 973                 *(p++) = 0x1;
 974         else
 975                 *(p++)=s->version&0xff;
 976
 977         /* field where we are to write out packet length */
 978         plen=p;
 979         p+=2;
 980         /* Explicit IV length, block ciphers appropriate version flag */
 981         if (s->enc_write_ctx && SSL_USE_EXPLICIT_IV(s))
 982                 {
 983                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
 984                 if (mode == EVP_CIPH_CBC_MODE)
 985                         {
 986                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
 987                         if (eivlen <= 1)
 988                                 eivlen = 0;
 989                         }
 990                 /* Need explicit part of IV for GCM mode */
 991                 else if (mode == EVP_CIPH_GCM_MODE)
 992                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
 993                 else
 994                         eivlen = 0;
 995                 }
 996         else
 997                 eivlen = 0;
 998
 999         /* lets setup the record stuff. */
1000         wr->data=p + eivlen;
1001         wr->length=(int)len;
1002         wr->input=(unsigned char *)buf;
1003
1004         /* we now 'read' from wr->input, wr->length bytes into
1005          * wr->data */
1006
1007         /* first we compress */
1008         if (s->compress != NULL)
1009                 {
1010                 if (!ssl3_do_compress(s))
1011                         {
1012                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
1013                         goto err;
1014                         }
1015                 }
1016         else
1017                 {
1018                 memcpy(wr->data,wr->input,wr->length);
1019                 wr->input=wr->data;
1020                 }
1021
1022         /* we should still have the output to wr->data and the input
1023          * from wr->input.  Length should be wr->length.
1024          * wr->data still points in the wb->buf */
1025
1026         if (mac_size != 0)
1027                 {
1028                 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
1029                         goto err;
1030                 wr->length+=mac_size;
1031                 }
1032
1033         wr->input=p;
1034         wr->data=p;
1035
1036         if (eivlen)
1037                 {
1038         /*      if (RAND_pseudo_bytes(p, eivlen) <= 0)
1039                         goto err; */
1040                 wr->length += eivlen;
1041                 }
1042
1043         if(s->method->ssl3_enc->enc(s,1)<1) goto err;
1044
1045         /* record length after mac and block padding */
1046         s2n(wr->length,plen);
1047
1048         if (s->msg_callback)
1049                 s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s, s->msg_callback_arg);
1050
1051         /* we should now have
1052          * wr->data pointing to the encrypted data, which is
1053          * wr->length long */
1054         wr->type=type; /* not needed but helps for debugging */
1055         wr->length+=SSL3_RT_HEADER_LENGTH;
1056
1057         if (create_empty_fragment)
1058                 {
1059                 /* we are in a recursive call;
1060                  * just return the length, don't write out anything here
1061                  */
1062                 return wr->length;
1063                 }
1064
1065         /* now let's set up wb */
1066         wb->left = prefix_len + wr->length;
1067
1068         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1069         s->s3->wpend_tot=len;
1070         s->s3->wpend_buf=buf;
1071         s->s3->wpend_type=type;
1072         s->s3->wpend_ret=len;
1073
1074         /* we now just need to write the buffer */
1075         return ssl3_write_pending(s,type,buf,len);
1076 err:
1077         return -1;
1078         }
1079
1080 /* if s->s3->wbuf.left != 0, we need to call this */
1081 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
1082         unsigned int len)
1083         {
1084         int i;
1085         SSL3_BUFFER *wb=&(s->s3->wbuf);
1086
1087 /* XXXX */
1088         if ((s->s3->wpend_tot > (int)len)
1089                 || ((s->s3->wpend_buf != buf) &&
1090                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
1091                 || (s->s3->wpend_type != type))
1092                 {
1093                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
1094                 return(-1);
1095                 }
1096
1097         for (;;)
1098                 {
1099                 clear_sys_error();
1100                 if (s->wbio != NULL)
1101                         {
1102                         s->rwstate=SSL_WRITING;
1103                         i=BIO_write(s->wbio,
1104                                 (char *)&(wb->buf[wb->offset]),
1105                                 (unsigned int)wb->left);
1106                         }
1107                 else
1108                         {
1109                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
1110                         i= -1;
1111                         }
1112                 if (i == wb->left)
1113                         {
1114                         wb->left=0;
1115                         wb->offset+=i;
1116                         s->rwstate=SSL_NOTHING;
1117                         return(s->s3->wpend_ret);
1118                         }
1119                 else if (i <= 0) {
1120                         if (s->version == DTLS1_VERSION ||
1121                             s->version == DTLS1_BAD_VER) {
1122                                 /* For DTLS, just drop it. That's kind of the whole
1123                                    point in using a datagram service */
1124                                 wb->left = 0;
1125                         }
1126                         return(i);
1127                 }
1128                 wb->offset+=i;
1129                 wb->left-=i;
1130                 }
1131         }
1132
1133 /* Return up to 'len' payload bytes received in 'type' records.
1134  * 'type' is one of the following:
1135  *
1136  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
1137  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
1138  *   -  0 (during a shutdown, no data has to be returned)
1139  *
1140  * If we don't have stored data to work from, read a SSL/TLS record first
1141  * (possibly multiple records if we still don't have anything to return).
1142  *
1143  * This function must handle any surprises the peer may have for us, such as
1144  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
1145  * a surprise, but handled as if it were), or renegotiation requests.
1146  * Also if record payloads contain fragments too small to process, we store
1147  * them until there is enough for the respective protocol (the record protocol
1148  * may use arbitrary fragmentation and even interleaving):
1149  *     Change cipher spec protocol
1150  *             just 1 byte needed, no need for keeping anything stored
1151  *     Alert protocol
1152  *             2 bytes needed (AlertLevel, AlertDescription)
1153  *     Handshake protocol
1154  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
1155  *             to detect unexpected Client Hello and Hello Request messages
1156  *             here, anything else is handled by higher layers
1157  *     Application data protocol
1158  *             none of our business
1159  */
1160 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
1161         {
1162         int al,i,j,ret;
1163         unsigned int n;
1164         SSL3_RECORD *rr;
1165         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
1166
1167         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
1168                 if (!ssl3_setup_read_buffer(s))
1169                         return(-1);
1170
1171         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) ||
1172             (peek && (type != SSL3_RT_APPLICATION_DATA)))
1173                 {
1174                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1175                 return -1;
1176                 }
1177
1178         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
1179                 /* (partially) satisfy request from storage */
1180                 {
1181                 unsigned char *src = s->s3->handshake_fragment;
1182                 unsigned char *dst = buf;
1183                 unsigned int k;
1184
1185                 /* peek == 0 */
1186                 n = 0;
1187                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
1188                         {
1189                         *dst++ = *src++;
1190                         len--; s->s3->handshake_fragment_len--;
1191                         n++;
1192                         }
1193                 /* move any remaining fragment bytes: */
1194                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
1195                         s->s3->handshake_fragment[k] = *src++;
1196                 return n;
1197         }
1198
1199         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
1200
1201         if (!s->in_handshake && SSL_in_init(s))
1202                 {
1203                 /* type == SSL3_RT_APPLICATION_DATA */
1204                 i=s->handshake_func(s);
1205                 if (i < 0) return(i);
1206                 if (i == 0)
1207                         {
1208                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1209                         return(-1);
1210                         }
1211                 }
1212 start:
1213         s->rwstate=SSL_NOTHING;
1214
1215         /* s->s3->rrec.type         - is the type of record
1216          * s->s3->rrec.data,    - data
1217          * s->s3->rrec.off,     - offset into 'data' for next read
1218          * s->s3->rrec.length,  - number of bytes. */
1219         rr = &(s->s3->rrec);
1220
1221         /* get new packet if necessary */
1222         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1223                 {
1224                 ret=ssl3_get_record(s);
1225                 if (ret <= 0) return(ret);
1226                 }
1227
1228         /* we now have a packet which can be read and processed */
1229
1230         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1231                                        * reset by ssl3_get_finished */
1232                 && (rr->type != SSL3_RT_HANDSHAKE))
1233                 {
1234                 al=SSL_AD_UNEXPECTED_MESSAGE;
1235                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1236                 goto f_err;
1237                 }
1238
1239         /* If the other end has shut down, throw anything we read away
1240          * (even in 'peek' mode) */
1241         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1242                 {
1243                 rr->length=0;
1244                 s->rwstate=SSL_NOTHING;
1245                 return(0);
1246                 }
1247
1248
1249         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1250                 {
1251                 /* make sure that we are not getting application data when we
1252                  * are doing a handshake for the first time */
1253                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1254                         (s->enc_read_ctx == NULL))
1255                         {
1256                         al=SSL_AD_UNEXPECTED_MESSAGE;
1257                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1258                         goto f_err;
1259                         }
1260
1261                 if (len <= 0) return(len);
1262
1263                 if ((unsigned int)len > rr->length)
1264                         n = rr->length;
1265                 else
1266                         n = (unsigned int)len;
1267
1268                 memcpy(buf,&(rr->data[rr->off]),n);
1269                 if (!peek)
1270                         {
1271                         rr->length-=n;
1272                         rr->off+=n;
1273                         if (rr->length == 0)
1274                                 {
1275                                 s->rstate=SSL_ST_READ_HEADER;
1276                                 rr->off=0;
1277                                 if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0)
1278                                         ssl3_release_read_buffer(s);
1279                                 }
1280                         }
1281                 return(n);
1282                 }
1283
1284
1285         /* If we get here, then type != rr->type; if we have a handshake
1286          * message, then it was unexpected (Hello Request or Client Hello). */
1287
1288         /* In case of record types for which we have 'fragment' storage,
1289          * fill that so that we can process the data at a fixed place.
1290          */
1291                 {
1292                 unsigned int dest_maxlen = 0;
1293                 unsigned char *dest = NULL;
1294                 unsigned int *dest_len = NULL;
1295
1296                 if (rr->type == SSL3_RT_HANDSHAKE)
1297                         {
1298                         dest_maxlen = sizeof s->s3->handshake_fragment;
1299                         dest = s->s3->handshake_fragment;
1300                         dest_len = &s->s3->handshake_fragment_len;
1301                         }
1302                 else if (rr->type == SSL3_RT_ALERT)
1303                         {
1304                         dest_maxlen = sizeof s->s3->alert_fragment;
1305                         dest = s->s3->alert_fragment;
1306                         dest_len = &s->s3->alert_fragment_len;
1307                         }
1308 #ifndef OPENSSL_NO_HEARTBEATS
1309                 else if (rr->type == TLS1_RT_HEARTBEAT)
1310                         {
1311                         tls1_process_heartbeat(s);
1312
1313                         /* Exit and notify application to read again */
1314                         rr->length = 0;
1315                         s->rwstate=SSL_READING;
1316                         BIO_clear_retry_flags(SSL_get_rbio(s));
1317                         BIO_set_retry_read(SSL_get_rbio(s));
1318                         return(-1);
1319                         }
1320 #endif
1321
1322                 if (dest_maxlen > 0)
1323                         {
1324                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
1325                         if (rr->length < n)
1326                                 n = rr->length; /* available bytes */
1327
1328                         /* now move 'n' bytes: */
1329                         while (n-- > 0)
1330                                 {
1331                                 dest[(*dest_len)++] = rr->data[rr->off++];
1332                                 rr->length--;
1333                                 }
1334
1335                         if (*dest_len < dest_maxlen)
1336                                 goto start; /* fragment was too small */
1337                         }
1338                 }
1339
1340         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1341          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1342          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1343
1344         /* If we are a client, check for an incoming 'Hello Request': */
1345         if ((!s->server) &&
1346                 (s->s3->handshake_fragment_len >= 4) &&
1347                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1348                 (s->session != NULL) && (s->session->cipher != NULL))
1349                 {
1350                 s->s3->handshake_fragment_len = 0;
1351
1352                 if ((s->s3->handshake_fragment[1] != 0) ||
1353                         (s->s3->handshake_fragment[2] != 0) ||
1354                         (s->s3->handshake_fragment[3] != 0))
1355                         {
1356                         al=SSL_AD_DECODE_ERROR;
1357                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1358                         goto f_err;
1359                         }
1360
1361                 if (s->msg_callback)
1362                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1363
1364                 if (SSL_is_init_finished(s) &&
1365                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1366                         !s->s3->renegotiate)
1367                         {
1368                         ssl3_renegotiate(s);
1369                         if (ssl3_renegotiate_check(s))
1370                                 {
1371                                 i=s->handshake_func(s);
1372                                 if (i < 0) return(i);
1373                                 if (i == 0)
1374                                         {
1375                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1376                                         return(-1);
1377                                         }
1378
1379                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1380                                         {
1381                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1382                                                 {
1383                                                 BIO *bio;
1384                                                 /* In the case where we try to read application data,
1385                                                  * but we trigger an SSL handshake, we return -1 with
1386                                                  * the retry option set.  Otherwise renegotiation may
1387                                                  * cause nasty problems in the blocking world */
1388                                                 s->rwstate=SSL_READING;
1389                                                 bio=SSL_get_rbio(s);
1390                                                 BIO_clear_retry_flags(bio);
1391                                                 BIO_set_retry_read(bio);
1392                                                 return(-1);
1393                                                 }
1394                                         }
1395                                 }
1396                         }
1397                 /* we either finished a handshake or ignored the request,
1398                  * now try again to obtain the (application) data we were asked for */
1399                 goto start;
1400                 }
1401         /* If we are a server and get a client hello when renegotiation isn't
1402          * allowed send back a no renegotiation alert and carry on.
1403          * WARNING: experimental code, needs reviewing (steve)
1404          */
1405         if (s->server &&
1406                 SSL_is_init_finished(s) &&
1407                 !s->s3->send_connection_binding &&
1408                 (s->version > SSL3_VERSION) &&
1409                 (s->s3->handshake_fragment_len >= 4) &&
1410                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1411                 (s->session != NULL) && (s->session->cipher != NULL) &&
1412                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1413
1414                 {
1415                 /*s->s3->handshake_fragment_len = 0;*/
1416                 rr->length = 0;
1417                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1418                 goto start;
1419                 }
1420         if (s->s3->alert_fragment_len >= 2)
1421                 {
1422                 int alert_level = s->s3->alert_fragment[0];
1423                 int alert_descr = s->s3->alert_fragment[1];
1424
1425                 s->s3->alert_fragment_len = 0;
1426
1427                 if (s->msg_callback)
1428                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1429
1430                 if (s->info_callback != NULL)
1431                         cb=s->info_callback;
1432                 else if (s->ctx->info_callback != NULL)
1433                         cb=s->ctx->info_callback;
1434
1435                 if (cb != NULL)
1436                         {
1437                         j = (alert_level << 8) | alert_descr;
1438                         cb(s, SSL_CB_READ_ALERT, j);
1439                         }
1440
1441                 if (alert_level == 1) /* warning */
1442                         {
1443                         s->s3->warn_alert = alert_descr;
1444                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1445                                 {
1446                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1447                                 return(0);
1448                                 }
1449                         /* This is a warning but we receive it if we requested
1450                          * renegotiation and the peer denied it. Terminate with
1451                          * a fatal alert because if application tried to
1452                          * renegotiatie it presumably had a good reason and
1453                          * expects it to succeed.
1454                          *
1455                          * In future we might have a renegotiation where we
1456                          * don't care if the peer refused it where we carry on.
1457                          */
1458                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1459                                 {
1460                                 al = SSL_AD_HANDSHAKE_FAILURE;
1461                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1462                                 goto f_err;
1463                                 }
1464 #ifdef SSL_AD_MISSING_SRP_USERNAME
1465                         else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1466                                 return(0);
1467 #endif
1468                         }
1469                 else if (alert_level == 2) /* fatal */
1470                         {
1471                         char tmp[16];
1472
1473                         s->rwstate=SSL_NOTHING;
1474                         s->s3->fatal_alert = alert_descr;
1475                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1476                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1477                         ERR_add_error_data(2,"SSL alert number ",tmp);
1478                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1479                         SSL_CTX_remove_session(s->ctx,s->session);
1480                         return(0);
1481                         }
1482                 else
1483                         {
1484                         al=SSL_AD_ILLEGAL_PARAMETER;
1485                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1486                         goto f_err;
1487                         }
1488
1489                 goto start;
1490                 }
1491
1492         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1493                 {
1494                 s->rwstate=SSL_NOTHING;
1495                 rr->length=0;
1496                 return(0);
1497                 }
1498
1499         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1500                 {
1501                 /* 'Change Cipher Spec' is just a single byte, so we know
1502                  * exactly what the record payload has to look like */
1503                 if (    (rr->length != 1) || (rr->off != 0) ||
1504                         (rr->data[0] != SSL3_MT_CCS))
1505                         {
1506                         al=SSL_AD_ILLEGAL_PARAMETER;
1507                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1508                         goto f_err;
1509                         }
1510
1511                 /* Check we have a cipher to change to */
1512                 if (s->s3->tmp.new_cipher == NULL)
1513                         {
1514                         al=SSL_AD_UNEXPECTED_MESSAGE;
1515                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1516                         goto f_err;
1517                         }
1518
1519                 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1520                         {
1521                         al=SSL_AD_UNEXPECTED_MESSAGE;
1522                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1523                         goto f_err;
1524                         }
1525
1526                 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1527
1528                 rr->length=0;
1529
1530                 if (s->msg_callback)
1531                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1532
1533                 s->s3->change_cipher_spec=1;
1534                 if (!ssl3_do_change_cipher_spec(s))
1535                         goto err;
1536                 else
1537                         goto start;
1538                 }
1539
1540         /* Unexpected handshake message (Client Hello, or protocol violation) */
1541         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1542                 {
1543                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1544                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1545                         {
1546 #if 0 /* worked only because C operator preferences are not as expected (and
1547        * because this is not really needed for clients except for detecting
1548        * protocol violations): */
1549                         s->state=SSL_ST_BEFORE|(s->server)
1550                                 ?SSL_ST_ACCEPT
1551                                 :SSL_ST_CONNECT;
1552 #else
1553                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1554 #endif
1555                         s->renegotiate=1;
1556                         s->new_session=1;
1557                         }
1558                 i=s->handshake_func(s);
1559                 if (i < 0) return(i);
1560                 if (i == 0)
1561                         {
1562                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1563                         return(-1);
1564                         }
1565
1566                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1567                         {
1568                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1569                                 {
1570                                 BIO *bio;
1571                                 /* In the case where we try to read application data,
1572                                  * but we trigger an SSL handshake, we return -1 with
1573                                  * the retry option set.  Otherwise renegotiation may
1574                                  * cause nasty problems in the blocking world */
1575                                 s->rwstate=SSL_READING;
1576                                 bio=SSL_get_rbio(s);
1577                                 BIO_clear_retry_flags(bio);
1578                                 BIO_set_retry_read(bio);
1579                                 return(-1);
1580                                 }
1581                         }
1582                 goto start;
1583                 }
1584
1585         switch (rr->type)
1586                 {
1587         default:
1588 #ifndef OPENSSL_NO_TLS
1589                 /* TLS up to v1.1 just ignores unknown message types:
1590                  * TLS v1.2 give an unexpected message alert.
1591                  */
1592                 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1593                         {
1594                         rr->length = 0;
1595                         goto start;
1596                         }
1597 #endif
1598                 al=SSL_AD_UNEXPECTED_MESSAGE;
1599                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1600                 goto f_err;
1601         case SSL3_RT_CHANGE_CIPHER_SPEC:
1602         case SSL3_RT_ALERT:
1603         case SSL3_RT_HANDSHAKE:
1604                 /* we already handled all of these, with the possible exception
1605                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1606                  * should not happen when type != rr->type */
1607                 al=SSL_AD_UNEXPECTED_MESSAGE;
1608                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1609                 goto f_err;
1610         case SSL3_RT_APPLICATION_DATA:
1611                 /* At this point, we were expecting handshake data,
1612                  * but have application data.  If the library was
1613                  * running inside ssl3_read() (i.e. in_read_app_data
1614                  * is set) and it makes sense to read application data
1615                  * at this point (session renegotiation not yet started),
1616                  * we will indulge it.
1617                  */
1618                 if (s->s3->in_read_app_data &&
1619                         (s->s3->total_renegotiations != 0) &&
1620                         ((
1621                                 (s->state & SSL_ST_CONNECT) &&
1622                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1623                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1624                                 ) || (
1625                                         (s->state & SSL_ST_ACCEPT) &&
1626                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1627                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1628                                         )
1629                                 ))
1630                         {
1631                         s->s3->in_read_app_data=2;
1632                         return(-1);
1633                         }
1634                 else
1635                         {
1636                         al=SSL_AD_UNEXPECTED_MESSAGE;
1637                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1638                         goto f_err;
1639                         }
1640                 }
1641         /* not reached */
1642
1643 f_err:
1644         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1645 err:
1646         return(-1);
1647         }
1648
1649 int ssl3_do_change_cipher_spec(SSL *s)
1650         {
1651         int i;
1652         const char *sender;
1653         int slen;
1654
1655         if (s->state & SSL_ST_ACCEPT)
1656                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1657         else
1658                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1659
1660         if (s->s3->tmp.key_block == NULL)
1661                 {
1662                 if (s->session == NULL || s->session->master_key_length == 0)
1663                         {
1664                         /* might happen if dtls1_read_bytes() calls this */
1665                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1666                         return (0);
1667                         }
1668
1669                 s->session->cipher=s->s3->tmp.new_cipher;
1670                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1671                 }
1672
1673         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1674                 return(0);
1675
1676         /* we have to record the message digest at
1677          * this point so we can get it before we read
1678          * the finished message */
1679         if (s->state & SSL_ST_CONNECT)
1680                 {
1681                 sender=s->method->ssl3_enc->server_finished_label;
1682                 slen=s->method->ssl3_enc->server_finished_label_len;
1683                 }
1684         else
1685                 {
1686                 sender=s->method->ssl3_enc->client_finished_label;
1687                 slen=s->method->ssl3_enc->client_finished_label_len;
1688                 }
1689
1690         i = s->method->ssl3_enc->final_finish_mac(s,
1691                 sender,slen,s->s3->tmp.peer_finish_md);
1692         if (i == 0)
1693                 {
1694                 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
1695                 return 0;
1696                 }
1697         s->s3->tmp.peer_finish_md_len = i;
1698
1699         return(1);
1700         }
1701
1702 int ssl3_send_alert(SSL *s, int level, int desc)
1703         {
1704         /* Map tls/ssl alert value to correct one */
1705         desc=s->method->ssl3_enc->alert_value(desc);
1706         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1707                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1708         if (desc < 0) return -1;
1709         /* If a fatal one, remove from cache */
1710         if ((level == 2) && (s->session != NULL))
1711                 SSL_CTX_remove_session(s->ctx,s->session);
1712
1713         s->s3->alert_dispatch=1;
1714         s->s3->send_alert[0]=level;
1715         s->s3->send_alert[1]=desc;
1716         if (s->s3->wbuf.left == 0) /* data still being written out? */
1717                 return s->method->ssl_dispatch_alert(s);
1718         /* else data is still being written out, we will get written
1719          * some time in the future */
1720         return -1;
1721         }
1722
1723 int ssl3_dispatch_alert(SSL *s)
1724         {
1725         int i,j;
1726         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1727
1728         s->s3->alert_dispatch=0;
1729         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1730         if (i <= 0)
1731                 {
1732                 s->s3->alert_dispatch=1;
1733                 }
1734         else
1735                 {
1736                 /* Alert sent to BIO.  If it is important, flush it now.
1737                  * If the message does not get sent due to non-blocking IO,
1738                  * we will not worry too much. */
1739                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1740                         (void)BIO_flush(s->wbio);
1741
1742                 if (s->msg_callback)
1743                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1744
1745                 if (s->info_callback != NULL)
1746                         cb=s->info_callback;
1747                 else if (s->ctx->info_callback != NULL)
1748                         cb=s->ctx->info_callback;
1749
1750                 if (cb != NULL)
1751                         {
1752                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1753                         cb(s,SSL_CB_WRITE_ALERT,j);
1754                         }
1755                 }
1756         return(i);
1757         }