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