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 && extend)
 201                         return 0;
 202                 if (left > 0 && n > left)
 203                         n = left;
 204                 }
 205
 206         /* if there is enough in the buffer from a previous read, take some */
 207         if (left >= n)
 208                 {
 209                 s->packet_length+=n;
 210                 rb->left=left-n;
 211                 rb->offset+=n;
 212                 return(n);
 213                 }
 214
 215         /* else we need to read more data */
 216
 217         len = s->packet_length;
 218         pkt = rb->buf+align;
 219         /* Move any available bytes to front of buffer:
 220          * 'len' bytes already pointed to by 'packet',
 221          * 'left' extra ones at the end */
 222         if (s->packet != pkt) /* len > 0 */
 223                 {
 224                 memmove(pkt, s->packet, len+left);
 225                 s->packet = pkt;
 226                 rb->offset = len + align;
 227                 }
 228
 229         if (n > (int)(rb->len - rb->offset)) /* does not happen */
 230                 {
 231                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 232                 return -1;
 233                 }
 234
 235         if (!s->read_ahead)
 236                 /* ignore max parameter */
 237                 max = n;
 238         else
 239                 {
 240                 if (max < n)
 241                         max = n;
 242                 if (max > (int)(rb->len - rb->offset))
 243                         max = rb->len - rb->offset;
 244                 }
 245
 246         while (left < n)
 247                 {
 248                 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
 249                  * and need to read in more until we have len+n (up to
 250                  * len+max if possible) */
 251
 252                 clear_sys_error();
 253                 if (s->rbio != NULL)
 254                         {
 255                         s->rwstate=SSL_READING;
 256                         i=BIO_read(s->rbio,pkt+len+left, max-left);
 257                         }
 258                 else
 259                         {
 260                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 261                         i = -1;
 262                         }
 263
 264                 if (i <= 0)
 265                         {
 266                         rb->left = left;
 267                         if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
 268                                 !SSL_IS_DTLS(s))
 269                                 if (len+left == 0)
 270                                         ssl3_release_read_buffer(s);
 271                         return(i);
 272                         }
 273                 left+=i;
 274                 /* reads should *never* span multiple packets for DTLS because
 275                  * the underlying transport protocol is message oriented as opposed
 276                  * to byte oriented as in the TLS case. */
 277                 if (SSL_IS_DTLS(s))
 278                         {
 279                         if (n > left)
 280                                 n = left; /* makes the while condition false */
 281                         }
 282                 }
 283
 284         /* done reading, now the book-keeping */
 285         rb->offset += n;
 286         rb->left = left - n;
 287         s->packet_length += n;
 288         s->rwstate=SSL_NOTHING;
 289         return(n);
 290         }
 291
 292 /* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will
 293  * be processed per call to ssl3_get_record. Without this limit an attacker
 294  * could send empty records at a faster rate than we can process and cause
 295  * ssl3_get_record to loop forever. */
 296 #define MAX_EMPTY_RECORDS 32
 297
 298 /*-
 299  * Call this to get a new input record.
 300  * It will return <= 0 if more data is needed, normally due to an error
 301  * or non-blocking IO.
 302  * When it finishes, one packet has been decoded and can be found in
 303  * ssl->s3->rrec.type    - is the type of record
 304  * ssl->s3->rrec.data,   - data
 305  * ssl->s3->rrec.length, - number of bytes
 306  */
 307 /* used only by ssl3_read_bytes */
 308 static int ssl3_get_record(SSL *s)
 309         {
 310         int ssl_major,ssl_minor,al;
 311         int enc_err,n,i,ret= -1;
 312         SSL3_RECORD *rr;
 313         SSL_SESSION *sess;
 314         unsigned char *p;
 315         unsigned char md[EVP_MAX_MD_SIZE];
 316         short version;
 317         unsigned mac_size, orig_len;
 318         size_t extra;
 319         unsigned empty_record_count = 0;
 320
 321         rr= &(s->s3->rrec);
 322         sess=s->session;
 323
 324         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 325                 extra=SSL3_RT_MAX_EXTRA;
 326         else
 327                 extra=0;
 328         if (extra && !s->s3->init_extra)
 329                 {
 330                 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
 331                  * set after ssl3_setup_buffers() was done */
 332                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
 333                 return -1;
 334                 }
 335
 336 again:
 337         /* check if we have the header */
 338         if (    (s->rstate != SSL_ST_READ_BODY) ||
 339                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 340                 {
 341                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 342                 if (n <= 0) return(n); /* error or non-blocking */
 343                 s->rstate=SSL_ST_READ_BODY;
 344
 345                 p=s->packet;
 346                 if (s->msg_callback)
 347                         s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s, s->msg_callback_arg);
 348
 349                 /* Pull apart the header into the SSL3_RECORD */
 350                 rr->type= *(p++);
 351                 ssl_major= *(p++);
 352                 ssl_minor= *(p++);
 353                 version=(ssl_major<<8)|ssl_minor;
 354                 n2s(p,rr->length);
 355 #if 0
 356 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
 357 #endif
 358
 359                 /* Lets check version */
 360                 if (!s->first_packet)
 361                         {
 362                         if (version != s->version)
 363                                 {
 364                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 365                                 if ((s->version & 0xFF00) == (version & 0xFF00) && !s->enc_write_ctx && !s->write_hash)
 366                                         /* Send back error using their minor version number :-) */
 367                                         s->version = (unsigned short)version;
 368                                 al=SSL_AD_PROTOCOL_VERSION;
 369                                 goto f_err;
 370                                 }
 371                         }
 372
 373                 if ((version>>8) != SSL3_VERSION_MAJOR)
 374                         {
 375                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 376                         goto err;
 377                         }
 378
 379                 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
 380                         {
 381                         al=SSL_AD_RECORD_OVERFLOW;
 382                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 383                         goto f_err;
 384                         }
 385
 386                 /* now s->rstate == SSL_ST_READ_BODY */
 387                 }
 388
 389         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 390
 391         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
 392                 {
 393                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
 394                 i=rr->length;
 395                 n=ssl3_read_n(s,i,i,1);
 396                 if (n <= 0) return(n); /* error or non-blocking io */
 397                 /* now n == rr->length,
 398                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
 399                 }
 400
 401         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 402
 403         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 404          * and we have that many bytes in s->packet
 405          */
 406         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 407
 408         /* ok, we can now read from 's->packet' data into 'rr'
 409          * rr->input points at rr->length bytes, which
 410          * need to be copied into rr->data by either
 411          * the decryption or by the decompression
 412          * When the data is 'copied' into the rr->data buffer,
 413          * rr->input will be pointed at the new buffer */
 414
 415         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 416          * rr->length bytes of encrypted compressed stuff. */
 417
 418         /* check is not needed I believe */
 419         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 420                 {
 421                 al=SSL_AD_RECORD_OVERFLOW;
 422                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 423                 goto f_err;
 424                 }
 425
 426         /* decrypt in place in 'rr->input' */
 427         rr->data=rr->input;
 428
 429         enc_err = s->method->ssl3_enc->enc(s,0);
 430         /*-
 431          * enc_err is:
 432          *    0: (in non-constant time) if the record is publically invalid.
 433          *    1: if the padding is valid
 434          *    -1: if the padding is invalid
 435          */
 436         if (enc_err == 0)
 437                 {
 438                 al=SSL_AD_DECRYPTION_FAILED;
 439                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
 440                 goto f_err;
 441                 }
 442
 443 #ifdef TLS_DEBUG
 444 printf("dec %d\n",rr->length);
 445 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 446 printf("\n");
 447 #endif
 448
 449         /* r->length is now the compressed data plus mac */
 450         if ((sess != NULL) &&
 451             (s->enc_read_ctx != NULL) &&
 452             (EVP_MD_CTX_md(s->read_hash) != NULL))
 453                 {
 454                 /* s->read_hash != NULL => mac_size != -1 */
 455                 unsigned char *mac = NULL;
 456                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 457                 mac_size=EVP_MD_CTX_size(s->read_hash);
 458                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 459
 460                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 461                 orig_len = rr->length+((unsigned int)rr->type>>8);
 462
 463                 /* orig_len is the length of the record before any padding was
 464                  * removed. This is public information, as is the MAC in use,
 465                  * therefore we can safely process the record in a different
 466                  * amount of time if it's too short to possibly contain a MAC.
 467                  */
 468                 if (orig_len < mac_size ||
 469                     /* CBC records must have a padding length byte too. */
 470                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 471                      orig_len < mac_size+1))
 472                         {
 473                         al=SSL_AD_DECODE_ERROR;
 474                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 475                         goto f_err;
 476                         }
 477
 478                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 479                         {
 480                         /* We update the length so that the TLS header bytes
 481                          * can be constructed correctly but we need to extract
 482                          * the MAC in constant time from within the record,
 483                          * without leaking the contents of the padding bytes.
 484                          * */
 485                         mac = mac_tmp;
 486                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 487                         rr->length -= mac_size;
 488                         }
 489                 else
 490                         {
 491                         /* In this case there's no padding, so |orig_len|
 492                          * equals |rec->length| and we checked that there's
 493                          * enough bytes for |mac_size| above. */
 494                         rr->length -= mac_size;
 495                         mac = &rr->data[rr->length];
 496                         }
 497
 498                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 499                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 500                         enc_err = -1;
 501                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 502                         enc_err = -1;
 503                 }
 504
 505         if (enc_err < 0)
 506                 {
 507                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
 508                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
 509                  * failure is directly visible from the ciphertext anyway,
 510                  * we should not reveal which kind of error occured -- this
 511                  * might become visible to an attacker (e.g. via a logfile) */
 512                 al=SSL_AD_BAD_RECORD_MAC;
 513                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
 514                 goto f_err;
 515                 }
 516
 517         /* r->length is now just compressed */
 518         if (s->expand != NULL)
 519                 {
 520                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 521                         {
 522                         al=SSL_AD_RECORD_OVERFLOW;
 523                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 524                         goto f_err;
 525                         }
 526                 if (!ssl3_do_uncompress(s))
 527                         {
 528                         al=SSL_AD_DECOMPRESSION_FAILURE;
 529                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 530                         goto f_err;
 531                         }
 532                 }
 533
 534         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
 535                 {
 536                 al=SSL_AD_RECORD_OVERFLOW;
 537                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 538                 goto f_err;
 539                 }
 540
 541         rr->off=0;
 542         /*-
 543          * So at this point the following is true
 544          * ssl->s3->rrec.type   is the type of record
 545          * ssl->s3->rrec.length == number of bytes in record
 546          * ssl->s3->rrec.off    == offset to first valid byte
 547          * ssl->s3->rrec.data   == where to take bytes from, increment
 548          *                         after use :-).
 549          */
 550
 551         /* we have pulled in a full packet so zero things */
 552         s->packet_length=0;
 553
 554         /* just read a 0 length packet */
 555         if (rr->length == 0)
 556                 {
 557                 empty_record_count++;
 558                 if (empty_record_count > MAX_EMPTY_RECORDS)
 559                         {
 560                         al=SSL_AD_UNEXPECTED_MESSAGE;
 561                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL);
 562                         goto f_err;
 563                         }
 564                 goto again;
 565                 }
 566
 567 #if 0
 568 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
 569 #endif
 570
 571         return(1);
 572
 573 f_err:
 574         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 575 err:
 576         return(ret);
 577         }
 578
 579 int ssl3_do_uncompress(SSL *ssl)
 580         {
 581 #ifndef OPENSSL_NO_COMP
 582         int i;
 583         SSL3_RECORD *rr;
 584
 585         rr= &(ssl->s3->rrec);
 586         i=COMP_expand_block(ssl->expand,rr->comp,
 587                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 588         if (i < 0)
 589                 return(0);
 590         else
 591                 rr->length=i;
 592         rr->data=rr->comp;
 593 #endif
 594         return(1);
 595         }
 596
 597 int ssl3_do_compress(SSL *ssl)
 598         {
 599 #ifndef OPENSSL_NO_COMP
 600         int i;
 601         SSL3_RECORD *wr;
 602
 603         wr= &(ssl->s3->wrec);
 604         i=COMP_compress_block(ssl->compress,wr->data,
 605                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 606                 wr->input,(int)wr->length);
 607         if (i < 0)
 608                 return(0);
 609         else
 610                 wr->length=i;
 611
 612         wr->input=wr->data;
 613 #endif
 614         return(1);
 615         }
 616
 617 /* Call this to write data in records of type 'type'
 618  * It will return <= 0 if not all data has been sent or non-blocking IO.
 619  */
 620 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 621         {
 622         const unsigned char *buf=buf_;
 623         int tot;
 624         unsigned int n,nw;
 625 #if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
 626         unsigned int max_send_fragment;
 627 #endif
 628         SSL3_BUFFER *wb=&(s->s3->wbuf);
 629         int i;
 630
 631         s->rwstate=SSL_NOTHING;
 632         OPENSSL_assert(s->s3->wnum <= INT_MAX);
 633         tot=s->s3->wnum;
 634         s->s3->wnum=0;
 635
 636         if (SSL_in_init(s) && !s->in_handshake)
 637                 {
 638                 i=s->handshake_func(s);
 639                 if (i < 0) return(i);
 640                 if (i == 0)
 641                         {
 642                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 643                         return -1;
 644                         }
 645                 }
 646
 647         /* ensure that if we end up with a smaller value of data to write
 648          * out than the the original len from a write which didn't complete
 649          * for non-blocking I/O and also somehow ended up avoiding
 650          * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
 651          * it must never be possible to end up with (len-tot) as a large
 652          * number that will then promptly send beyond the end of the users
 653          * buffer ... so we trap and report the error in a way the user
 654          * will notice
 655          */
 656         if (len < tot)
 657                 {
 658                 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
 659                 return(-1);
 660                 }
 661
 662         /* first check if there is a SSL3_BUFFER still being written
 663          * out.  This will happen with non blocking IO */
 664         if (wb->left != 0)
 665                 {
 666                 i = ssl3_write_pending(s,type,&buf[tot],s->s3->wpend_tot);
 667                 if (i<=0)
 668                         {
 669                         /* XXX should we ssl3_release_write_buffer if i<0? */
 670                         s->s3->wnum=tot;
 671                         return i;
 672                         }
 673                 tot += i;       /* this might be last fragment */
 674                 }
 675
 676 #if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
 677         /*
 678          * Depending on platform multi-block can deliver several *times*
 679          * better performance. Downside is that it has to allocate
 680          * jumbo buffer to accomodate up to 8 records, but the
 681          * compromise is considered worthy.
 682          */
 683         if (type==SSL3_RT_APPLICATION_DATA &&
 684             len >= 4*(int)(max_send_fragment=s->max_send_fragment) &&
 685             s->compress==NULL && s->msg_callback==NULL &&
 686             SSL_USE_EXPLICIT_IV(s) &&
 687             EVP_CIPHER_flags(s->enc_write_ctx->cipher)&EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK)
 688                 {
 689                 unsigned char aad[13];
 690                 EVP_CTRL_TLS1_1_MULTIBLOCK_PARAM mb_param;
 691                 int packlen;
 692
 693                 /* minimize address aliasing conflicts */
 694                 if ((max_send_fragment&0xfff) == 0)
 695                         max_send_fragment -= 512;
 696
 697                 if (tot==0 || wb->buf==NULL)    /* allocate jumbo buffer */
 698                         {
 699                         ssl3_release_write_buffer(s);
 700
 701                         packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
 702                                         EVP_CTRL_TLS1_1_MULTIBLOCK_MAX_BUFSIZE,
 703                                         max_send_fragment,NULL);
 704
 705                         if (len>=8*(int)max_send_fragment)      packlen *= 8;
 706                         else                            packlen *= 4;
 707
 708                         wb->buf=OPENSSL_malloc(packlen);
 709                         wb->len=packlen;
 710                         }
 711                 else if (tot==len)              /* done? */
 712                         {
 713                         OPENSSL_free(wb->buf);  /* free jumbo buffer */
 714                         wb->buf = NULL;
 715                         return tot;
 716                         }
 717
 718                 n=(len-tot);
 719                 for (;;)
 720                         {
 721                         if (n < 4*max_send_fragment)
 722                                 {
 723                                 OPENSSL_free(wb->buf);  /* free jumbo buffer */
 724                                 wb->buf = NULL;
 725                                 break;
 726                                 }
 727
 728                         if (s->s3->alert_dispatch)
 729                                 {
 730                                 i=s->method->ssl_dispatch_alert(s);
 731                                 if (i <= 0)
 732                                         {
 733                                         s->s3->wnum=tot;
 734                                         return i;
 735                                         }
 736                                 }
 737
 738                         if (n >= 8*max_send_fragment)
 739                                 nw = max_send_fragment*(mb_param.interleave=8);
 740                         else
 741                                 nw = max_send_fragment*(mb_param.interleave=4);
 742
 743                         memcpy(aad,s->s3->write_sequence,8);
 744                         aad[8]=type;
 745                         aad[9]=(unsigned char)(s->version>>8);
 746                         aad[10]=(unsigned char)(s->version);
 747                         aad[11]=0;
 748                         aad[12]=0;
 749                         mb_param.out = NULL;
 750                         mb_param.inp = aad;
 751                         mb_param.len = nw;
 752
 753                         packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
 754                                         EVP_CTRL_TLS1_1_MULTIBLOCK_AAD,
 755                                         sizeof(mb_param),&mb_param);
 756
 757                         if (packlen<=0 || packlen>(int)wb->len) /* never happens */
 758                                 {
 759                                 OPENSSL_free(wb->buf);  /* free jumbo buffer */
 760                                 wb->buf = NULL;
 761                                 break;
 762                                 }
 763
 764                         mb_param.out = wb->buf;
 765                         mb_param.inp = &buf[tot];
 766                         mb_param.len = nw;
 767
 768                         if (EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
 769                                         EVP_CTRL_TLS1_1_MULTIBLOCK_ENCRYPT,
 770                                         sizeof(mb_param),&mb_param)<=0)
 771                                 return -1;
 772
 773                         s->s3->write_sequence[7] += mb_param.interleave;
 774                         if (s->s3->write_sequence[7] < mb_param.interleave)
 775                                 {
 776                                 int j=6;
 777                                 while (j>=0 && (++s->s3->write_sequence[j--])==0) ;
 778                                 }
 779
 780                         wb->offset = 0;
 781                         wb->left = packlen;
 782
 783                         s->s3->wpend_tot = nw;
 784                         s->s3->wpend_buf = &buf[tot];
 785                         s->s3->wpend_type= type;
 786                         s->s3->wpend_ret = nw;
 787
 788                         i = ssl3_write_pending(s,type,&buf[tot],nw);
 789                         if (i<=0)
 790                                 {
 791                                 if (i<0)
 792                                         {
 793                                         OPENSSL_free(wb->buf);
 794                                         wb->buf = NULL;
 795                                         }
 796                                 s->s3->wnum=tot;
 797                                 return i;
 798                                 }
 799                         if (i==(int)n)
 800                                 {
 801                                 OPENSSL_free(wb->buf);  /* free jumbo buffer */
 802                                 wb->buf = NULL;
 803                                 return tot+i;
 804                                 }
 805                         n-=i;
 806                         tot+=i;
 807                         }
 808                 }
 809         else
 810 #endif
 811         if (tot==len)           /* done? */
 812                 {
 813                 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
 814                         !SSL_IS_DTLS(s))
 815                         ssl3_release_write_buffer(s);
 816
 817                 return tot;
 818                 }
 819
 820
 821         n=(len-tot);
 822         for (;;)
 823                 {
 824                 if (n > s->max_send_fragment)
 825                         nw=s->max_send_fragment;
 826                 else
 827                         nw=n;
 828
 829                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
 830                 if (i <= 0)
 831                         {
 832                         /* XXX should we ssl3_release_write_buffer if i<0? */
 833                         s->s3->wnum=tot;
 834                         return i;
 835                         }
 836
 837                 if ((i == (int)n) ||
 838                         (type == SSL3_RT_APPLICATION_DATA &&
 839                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 840                         {
 841                         /* next chunk of data should get another prepended empty fragment
 842                          * in ciphersuites with known-IV weakness: */
 843                         s->s3->empty_fragment_done = 0;
 844
 845                         if ((i==(int)n) && s->mode & SSL_MODE_RELEASE_BUFFERS &&
 846                                 !SSL_IS_DTLS(s))
 847                                 ssl3_release_write_buffer(s);
 848
 849                         return tot+i;
 850                         }
 851
 852                 n-=i;
 853                 tot+=i;
 854                 }
 855         }
 856
 857 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 858                          unsigned int len, int create_empty_fragment)
 859         {
 860         unsigned char *p,*plen;
 861         int i,mac_size,clear=0;
 862         int prefix_len=0;
 863         int eivlen;
 864         long align=0;
 865         SSL3_RECORD *wr;
 866         SSL3_BUFFER *wb=&(s->s3->wbuf);
 867         SSL_SESSION *sess;
 868
 869
 870         /* first check if there is a SSL3_BUFFER still being written
 871          * out.  This will happen with non blocking IO */
 872         if (wb->left != 0)
 873                 return(ssl3_write_pending(s,type,buf,len));
 874
 875         /* If we have an alert to send, lets send it */
 876         if (s->s3->alert_dispatch)
 877                 {
 878                 i=s->method->ssl_dispatch_alert(s);
 879                 if (i <= 0)
 880                         return(i);
 881                 /* if it went, fall through and send more stuff */
 882                 }
 883
 884         if (wb->buf == NULL)
 885                 if (!ssl3_setup_write_buffer(s))
 886                         return -1;
 887
 888         if (len == 0 && !create_empty_fragment)
 889                 return 0;
 890
 891         wr= &(s->s3->wrec);
 892         sess=s->session;
 893
 894         if (    (sess == NULL) ||
 895                 (s->enc_write_ctx == NULL) ||
 896                 (EVP_MD_CTX_md(s->write_hash) == NULL))
 897                 {
 898 #if 1
 899                 clear=s->enc_write_ctx?0:1;     /* must be AEAD cipher */
 900 #else
 901                 clear=1;
 902 #endif
 903                 mac_size=0;
 904                 }
 905         else
 906                 {
 907                 mac_size=EVP_MD_CTX_size(s->write_hash);
 908                 if (mac_size < 0)
 909                         goto err;
 910                 }
 911
 912         /* 'create_empty_fragment' is true only when this function calls itself */
 913         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
 914                 {
 915                 /* countermeasure against known-IV weakness in CBC ciphersuites
 916                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
 917
 918                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
 919                         {
 920                         /* recursive function call with 'create_empty_fragment' set;
 921                          * this prepares and buffers the data for an empty fragment
 922                          * (these 'prefix_len' bytes are sent out later
 923                          * together with the actual payload) */
 924                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
 925                         if (prefix_len <= 0)
 926                                 goto err;
 927
 928                         if (prefix_len >
 929                 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
 930                                 {
 931                                 /* insufficient space */
 932                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
 933                                 goto err;
 934                                 }
 935                         }
 936
 937                 s->s3->empty_fragment_done = 1;
 938                 }
 939
 940         if (create_empty_fragment)
 941                 {
 942 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
 943                 /* extra fragment would be couple of cipher blocks,
 944                  * which would be multiple of SSL3_ALIGN_PAYLOAD, so
 945                  * if we want to align the real payload, then we can
 946                  * just pretent we simply have two headers. */
 947                 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
 948                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
 949 #endif
 950                 p = wb->buf + align;
 951                 wb->offset  = align;
 952                 }
 953         else if (prefix_len)
 954                 {
 955                 p = wb->buf + wb->offset + prefix_len;
 956                 }
 957         else
 958                 {
 959 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
 960                 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
 961                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
 962 #endif
 963                 p = wb->buf + align;
 964                 wb->offset  = align;
 965                 }
 966
 967         /* write the header */
 968
 969         *(p++)=type&0xff;
 970         wr->type=type;
 971
 972         *(p++)=(s->version>>8);
 973         /* Some servers hang if iniatial client hello is larger than 256
 974          * bytes and record version number > TLS 1.0
 975          */
 976         if (s->state == SSL3_ST_CW_CLNT_HELLO_B
 977                                 && !s->renegotiate
 978                                 && TLS1_get_version(s) > TLS1_VERSION)
 979                 *(p++) = 0x1;
 980         else
 981                 *(p++)=s->version&0xff;
 982
 983         /* field where we are to write out packet length */
 984         plen=p;
 985         p+=2;
 986         /* Explicit IV length, block ciphers appropriate version flag */
 987         if (s->enc_write_ctx && SSL_USE_EXPLICIT_IV(s))
 988                 {
 989                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
 990                 if (mode == EVP_CIPH_CBC_MODE)
 991                         {
 992                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
 993                         if (eivlen <= 1)
 994                                 eivlen = 0;
 995                         }
 996                 /* Need explicit part of IV for GCM mode */
 997                 else if (mode == EVP_CIPH_GCM_MODE)
 998                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
 999                 else
1000                         eivlen = 0;
1001                 }
1002         else
1003                 eivlen = 0;
1004
1005         /* lets setup the record stuff. */
1006         wr->data=p + eivlen;
1007         wr->length=(int)len;
1008         wr->input=(unsigned char *)buf;
1009
1010         /* we now 'read' from wr->input, wr->length bytes into
1011          * wr->data */
1012
1013         /* first we compress */
1014         if (s->compress != NULL)
1015                 {
1016                 if (!ssl3_do_compress(s))
1017                         {
1018                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
1019                         goto err;
1020                         }
1021                 }
1022         else
1023                 {
1024                 memcpy(wr->data,wr->input,wr->length);
1025                 wr->input=wr->data;
1026                 }
1027
1028         /* we should still have the output to wr->data and the input
1029          * from wr->input.  Length should be wr->length.
1030          * wr->data still points in the wb->buf */
1031
1032         if (mac_size != 0)
1033                 {
1034                 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
1035                         goto err;
1036                 wr->length+=mac_size;
1037                 }
1038
1039         wr->input=p;
1040         wr->data=p;
1041
1042         if (eivlen)
1043                 {
1044         /*      if (RAND_pseudo_bytes(p, eivlen) <= 0)
1045                         goto err; */
1046                 wr->length += eivlen;
1047                 }
1048
1049         if(s->method->ssl3_enc->enc(s,1)<1) goto err;
1050
1051         /* record length after mac and block padding */
1052         s2n(wr->length,plen);
1053
1054         if (s->msg_callback)
1055                 s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s, s->msg_callback_arg);
1056
1057         /* we should now have
1058          * wr->data pointing to the encrypted data, which is
1059          * wr->length long */
1060         wr->type=type; /* not needed but helps for debugging */
1061         wr->length+=SSL3_RT_HEADER_LENGTH;
1062
1063         if (create_empty_fragment)
1064                 {
1065                 /* we are in a recursive call;
1066                  * just return the length, don't write out anything here
1067                  */
1068                 return wr->length;
1069                 }
1070
1071         /* now let's set up wb */
1072         wb->left = prefix_len + wr->length;
1073
1074         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1075         s->s3->wpend_tot=len;
1076         s->s3->wpend_buf=buf;
1077         s->s3->wpend_type=type;
1078         s->s3->wpend_ret=len;
1079
1080         /* we now just need to write the buffer */
1081         return ssl3_write_pending(s,type,buf,len);
1082 err:
1083         return -1;
1084         }
1085
1086 /* if s->s3->wbuf.left != 0, we need to call this */
1087 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
1088         unsigned int len)
1089         {
1090         int i;
1091         SSL3_BUFFER *wb=&(s->s3->wbuf);
1092
1093 /* XXXX */
1094         if ((s->s3->wpend_tot > (int)len)
1095                 || ((s->s3->wpend_buf != buf) &&
1096                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
1097                 || (s->s3->wpend_type != type))
1098                 {
1099                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
1100                 return(-1);
1101                 }
1102
1103         for (;;)
1104                 {
1105                 clear_sys_error();
1106                 if (s->wbio != NULL)
1107                         {
1108                         s->rwstate=SSL_WRITING;
1109                         i=BIO_write(s->wbio,
1110                                 (char *)&(wb->buf[wb->offset]),
1111                                 (unsigned int)wb->left);
1112                         }
1113                 else
1114                         {
1115                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
1116                         i= -1;
1117                         }
1118                 if (i == wb->left)
1119                         {
1120                         wb->left=0;
1121                         wb->offset+=i;
1122                         s->rwstate=SSL_NOTHING;
1123                         return(s->s3->wpend_ret);
1124                         }
1125                 else if (i <= 0) {
1126                         if (s->version == DTLS1_VERSION ||
1127                             s->version == DTLS1_BAD_VER) {
1128                                 /* For DTLS, just drop it. That's kind of the whole
1129                                    point in using a datagram service */
1130                                 wb->left = 0;
1131                         }
1132                         return(i);
1133                 }
1134                 wb->offset+=i;
1135                 wb->left-=i;
1136                 }
1137         }
1138
1139 /*-
1140  * Return up to 'len' payload bytes received in 'type' records.
1141  * 'type' is one of the following:
1142  *
1143  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
1144  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
1145  *   -  0 (during a shutdown, no data has to be returned)
1146  *
1147  * If we don't have stored data to work from, read a SSL/TLS record first
1148  * (possibly multiple records if we still don't have anything to return).
1149  *
1150  * This function must handle any surprises the peer may have for us, such as
1151  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
1152  * a surprise, but handled as if it were), or renegotiation requests.
1153  * Also if record payloads contain fragments too small to process, we store
1154  * them until there is enough for the respective protocol (the record protocol
1155  * may use arbitrary fragmentation and even interleaving):
1156  *     Change cipher spec protocol
1157  *             just 1 byte needed, no need for keeping anything stored
1158  *     Alert protocol
1159  *             2 bytes needed (AlertLevel, AlertDescription)
1160  *     Handshake protocol
1161  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
1162  *             to detect unexpected Client Hello and Hello Request messages
1163  *             here, anything else is handled by higher layers
1164  *     Application data protocol
1165  *             none of our business
1166  */
1167 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
1168         {
1169         int al,i,j,ret;
1170         unsigned int n;
1171         SSL3_RECORD *rr;
1172         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
1173
1174         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
1175                 if (!ssl3_setup_read_buffer(s))
1176                         return(-1);
1177
1178         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) ||
1179             (peek && (type != SSL3_RT_APPLICATION_DATA)))
1180                 {
1181                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1182                 return -1;
1183                 }
1184
1185         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
1186                 /* (partially) satisfy request from storage */
1187                 {
1188                 unsigned char *src = s->s3->handshake_fragment;
1189                 unsigned char *dst = buf;
1190                 unsigned int k;
1191
1192                 /* peek == 0 */
1193                 n = 0;
1194                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
1195                         {
1196                         *dst++ = *src++;
1197                         len--; s->s3->handshake_fragment_len--;
1198                         n++;
1199                         }
1200                 /* move any remaining fragment bytes: */
1201                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
1202                         s->s3->handshake_fragment[k] = *src++;
1203                 return n;
1204         }
1205
1206         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
1207
1208         if (!s->in_handshake && SSL_in_init(s))
1209                 {
1210                 /* type == SSL3_RT_APPLICATION_DATA */
1211                 i=s->handshake_func(s);
1212                 if (i < 0) return(i);
1213                 if (i == 0)
1214                         {
1215                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1216                         return(-1);
1217                         }
1218                 }
1219 start:
1220         s->rwstate=SSL_NOTHING;
1221
1222         /*-
1223          * s->s3->rrec.type         - is the type of record
1224          * s->s3->rrec.data,    - data
1225          * s->s3->rrec.off,     - offset into 'data' for next read
1226          * s->s3->rrec.length,  - number of bytes.
1227          */
1228         rr = &(s->s3->rrec);
1229
1230         /* get new packet if necessary */
1231         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1232                 {
1233                 ret=ssl3_get_record(s);
1234                 if (ret <= 0) return(ret);
1235                 }
1236
1237         /* we now have a packet which can be read and processed */
1238
1239         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1240                                        * reset by ssl3_get_finished */
1241                 && (rr->type != SSL3_RT_HANDSHAKE))
1242                 {
1243                 al=SSL_AD_UNEXPECTED_MESSAGE;
1244                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1245                 goto f_err;
1246                 }
1247
1248         /* If the other end has shut down, throw anything we read away
1249          * (even in 'peek' mode) */
1250         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1251                 {
1252                 rr->length=0;
1253                 s->rwstate=SSL_NOTHING;
1254                 return(0);
1255                 }
1256
1257
1258         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1259                 {
1260                 /* make sure that we are not getting application data when we
1261                  * are doing a handshake for the first time */
1262                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1263                         (s->enc_read_ctx == NULL))
1264                         {
1265                         al=SSL_AD_UNEXPECTED_MESSAGE;
1266                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1267                         goto f_err;
1268                         }
1269
1270                 if (len <= 0) return(len);
1271
1272                 if ((unsigned int)len > rr->length)
1273                         n = rr->length;
1274                 else
1275                         n = (unsigned int)len;
1276
1277                 memcpy(buf,&(rr->data[rr->off]),n);
1278                 if (!peek)
1279                         {
1280                         rr->length-=n;
1281                         rr->off+=n;
1282                         if (rr->length == 0)
1283                                 {
1284                                 s->rstate=SSL_ST_READ_HEADER;
1285                                 rr->off=0;
1286                                 if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0)
1287                                         ssl3_release_read_buffer(s);
1288                                 }
1289                         }
1290                 return(n);
1291                 }
1292
1293
1294         /* If we get here, then type != rr->type; if we have a handshake
1295          * message, then it was unexpected (Hello Request or Client Hello). */
1296
1297         /* In case of record types for which we have 'fragment' storage,
1298          * fill that so that we can process the data at a fixed place.
1299          */
1300                 {
1301                 unsigned int dest_maxlen = 0;
1302                 unsigned char *dest = NULL;
1303                 unsigned int *dest_len = NULL;
1304
1305                 if (rr->type == SSL3_RT_HANDSHAKE)
1306                         {
1307                         dest_maxlen = sizeof s->s3->handshake_fragment;
1308                         dest = s->s3->handshake_fragment;
1309                         dest_len = &s->s3->handshake_fragment_len;
1310                         }
1311                 else if (rr->type == SSL3_RT_ALERT)
1312                         {
1313                         dest_maxlen = sizeof s->s3->alert_fragment;
1314                         dest = s->s3->alert_fragment;
1315                         dest_len = &s->s3->alert_fragment_len;
1316                         }
1317 #ifndef OPENSSL_NO_HEARTBEATS
1318                 else if (rr->type == TLS1_RT_HEARTBEAT)
1319                         {
1320                         tls1_process_heartbeat(s);
1321
1322                         /* Exit and notify application to read again */
1323                         rr->length = 0;
1324                         s->rwstate=SSL_READING;
1325                         BIO_clear_retry_flags(SSL_get_rbio(s));
1326                         BIO_set_retry_read(SSL_get_rbio(s));
1327                         return(-1);
1328                         }
1329 #endif
1330
1331                 if (dest_maxlen > 0)
1332                         {
1333                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
1334                         if (rr->length < n)
1335                                 n = rr->length; /* available bytes */
1336
1337                         /* now move 'n' bytes: */
1338                         while (n-- > 0)
1339                                 {
1340                                 dest[(*dest_len)++] = rr->data[rr->off++];
1341                                 rr->length--;
1342                                 }
1343
1344                         if (*dest_len < dest_maxlen)
1345                                 goto start; /* fragment was too small */
1346                         }
1347                 }
1348
1349         /*-
1350          * s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1351          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1352          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1353          */
1354
1355         /* If we are a client, check for an incoming 'Hello Request': */
1356         if ((!s->server) &&
1357                 (s->s3->handshake_fragment_len >= 4) &&
1358                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1359                 (s->session != NULL) && (s->session->cipher != NULL))
1360                 {
1361                 s->s3->handshake_fragment_len = 0;
1362
1363                 if ((s->s3->handshake_fragment[1] != 0) ||
1364                         (s->s3->handshake_fragment[2] != 0) ||
1365                         (s->s3->handshake_fragment[3] != 0))
1366                         {
1367                         al=SSL_AD_DECODE_ERROR;
1368                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1369                         goto f_err;
1370                         }
1371
1372                 if (s->msg_callback)
1373                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1374
1375                 if (SSL_is_init_finished(s) &&
1376                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1377                         !s->s3->renegotiate)
1378                         {
1379                         ssl3_renegotiate(s);
1380                         if (ssl3_renegotiate_check(s))
1381                                 {
1382                                 i=s->handshake_func(s);
1383                                 if (i < 0) return(i);
1384                                 if (i == 0)
1385                                         {
1386                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1387                                         return(-1);
1388                                         }
1389
1390                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1391                                         {
1392                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1393                                                 {
1394                                                 BIO *bio;
1395                                                 /* In the case where we try to read application data,
1396                                                  * but we trigger an SSL handshake, we return -1 with
1397                                                  * the retry option set.  Otherwise renegotiation may
1398                                                  * cause nasty problems in the blocking world */
1399                                                 s->rwstate=SSL_READING;
1400                                                 bio=SSL_get_rbio(s);
1401                                                 BIO_clear_retry_flags(bio);
1402                                                 BIO_set_retry_read(bio);
1403                                                 return(-1);
1404                                                 }
1405                                         }
1406                                 }
1407                         }
1408                 /* we either finished a handshake or ignored the request,
1409                  * now try again to obtain the (application) data we were asked for */
1410                 goto start;
1411                 }
1412         /* If we are a server and get a client hello when renegotiation isn't
1413          * allowed send back a no renegotiation alert and carry on.
1414          * WARNING: experimental code, needs reviewing (steve)
1415          */
1416         if (s->server &&
1417                 SSL_is_init_finished(s) &&
1418                 !s->s3->send_connection_binding &&
1419                 (s->version > SSL3_VERSION) &&
1420                 (s->s3->handshake_fragment_len >= 4) &&
1421                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1422                 (s->session != NULL) && (s->session->cipher != NULL) &&
1423                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1424
1425                 {
1426                 /*s->s3->handshake_fragment_len = 0;*/
1427                 rr->length = 0;
1428                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1429                 goto start;
1430                 }
1431         if (s->s3->alert_fragment_len >= 2)
1432                 {
1433                 int alert_level = s->s3->alert_fragment[0];
1434                 int alert_descr = s->s3->alert_fragment[1];
1435
1436                 s->s3->alert_fragment_len = 0;
1437
1438                 if (s->msg_callback)
1439                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1440
1441                 if (s->info_callback != NULL)
1442                         cb=s->info_callback;
1443                 else if (s->ctx->info_callback != NULL)
1444                         cb=s->ctx->info_callback;
1445
1446                 if (cb != NULL)
1447                         {
1448                         j = (alert_level << 8) | alert_descr;
1449                         cb(s, SSL_CB_READ_ALERT, j);
1450                         }
1451
1452                 if (alert_level == 1) /* warning */
1453                         {
1454                         s->s3->warn_alert = alert_descr;
1455                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1456                                 {
1457                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1458                                 return(0);
1459                                 }
1460                         /* This is a warning but we receive it if we requested
1461                          * renegotiation and the peer denied it. Terminate with
1462                          * a fatal alert because if application tried to
1463                          * renegotiatie it presumably had a good reason and
1464                          * expects it to succeed.
1465                          *
1466                          * In future we might have a renegotiation where we
1467                          * don't care if the peer refused it where we carry on.
1468                          */
1469                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1470                                 {
1471                                 al = SSL_AD_HANDSHAKE_FAILURE;
1472                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1473                                 goto f_err;
1474                                 }
1475 #ifdef SSL_AD_MISSING_SRP_USERNAME
1476                         else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1477                                 return(0);
1478 #endif
1479                         }
1480                 else if (alert_level == 2) /* fatal */
1481                         {
1482                         char tmp[16];
1483
1484                         s->rwstate=SSL_NOTHING;
1485                         s->s3->fatal_alert = alert_descr;
1486                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1487                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1488                         ERR_add_error_data(2,"SSL alert number ",tmp);
1489                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1490                         SSL_CTX_remove_session(s->ctx,s->session);
1491                         return(0);
1492                         }
1493                 else
1494                         {
1495                         al=SSL_AD_ILLEGAL_PARAMETER;
1496                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1497                         goto f_err;
1498                         }
1499
1500                 goto start;
1501                 }
1502
1503         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1504                 {
1505                 s->rwstate=SSL_NOTHING;
1506                 rr->length=0;
1507                 return(0);
1508                 }
1509
1510         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1511                 {
1512                 /* 'Change Cipher Spec' is just a single byte, so we know
1513                  * exactly what the record payload has to look like */
1514                 if (    (rr->length != 1) || (rr->off != 0) ||
1515                         (rr->data[0] != SSL3_MT_CCS))
1516                         {
1517                         al=SSL_AD_ILLEGAL_PARAMETER;
1518                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1519                         goto f_err;
1520                         }
1521
1522                 /* Check we have a cipher to change to */
1523                 if (s->s3->tmp.new_cipher == NULL)
1524                         {
1525                         al=SSL_AD_UNEXPECTED_MESSAGE;
1526                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1527                         goto f_err;
1528                         }
1529
1530                 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1531                         {
1532                         al=SSL_AD_UNEXPECTED_MESSAGE;
1533                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1534                         goto f_err;
1535                         }
1536
1537                 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1538
1539                 rr->length=0;
1540
1541                 if (s->msg_callback)
1542                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1543
1544                 s->s3->change_cipher_spec=1;
1545                 if (!ssl3_do_change_cipher_spec(s))
1546                         goto err;
1547                 else
1548                         goto start;
1549                 }
1550
1551         /* Unexpected handshake message (Client Hello, or protocol violation) */
1552         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1553                 {
1554                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1555                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1556                         {
1557 #if 0 /* worked only because C operator preferences are not as expected (and
1558        * because this is not really needed for clients except for detecting
1559        * protocol violations): */
1560                         s->state=SSL_ST_BEFORE|(s->server)
1561                                 ?SSL_ST_ACCEPT
1562                                 :SSL_ST_CONNECT;
1563 #else
1564                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1565 #endif
1566                         s->renegotiate=1;
1567                         s->new_session=1;
1568                         }
1569                 i=s->handshake_func(s);
1570                 if (i < 0) return(i);
1571                 if (i == 0)
1572                         {
1573                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1574                         return(-1);
1575                         }
1576
1577                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1578                         {
1579                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1580                                 {
1581                                 BIO *bio;
1582                                 /* In the case where we try to read application data,
1583                                  * but we trigger an SSL handshake, we return -1 with
1584                                  * the retry option set.  Otherwise renegotiation may
1585                                  * cause nasty problems in the blocking world */
1586                                 s->rwstate=SSL_READING;
1587                                 bio=SSL_get_rbio(s);
1588                                 BIO_clear_retry_flags(bio);
1589                                 BIO_set_retry_read(bio);
1590                                 return(-1);
1591                                 }
1592                         }
1593                 goto start;
1594                 }
1595
1596         switch (rr->type)
1597                 {
1598         default:
1599 #ifndef OPENSSL_NO_TLS
1600                 /* TLS up to v1.1 just ignores unknown message types:
1601                  * TLS v1.2 give an unexpected message alert.
1602                  */
1603                 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1604                         {
1605                         rr->length = 0;
1606                         goto start;
1607                         }
1608 #endif
1609                 al=SSL_AD_UNEXPECTED_MESSAGE;
1610                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1611                 goto f_err;
1612         case SSL3_RT_CHANGE_CIPHER_SPEC:
1613         case SSL3_RT_ALERT:
1614         case SSL3_RT_HANDSHAKE:
1615                 /* we already handled all of these, with the possible exception
1616                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1617                  * should not happen when type != rr->type */
1618                 al=SSL_AD_UNEXPECTED_MESSAGE;
1619                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1620                 goto f_err;
1621         case SSL3_RT_APPLICATION_DATA:
1622                 /* At this point, we were expecting handshake data,
1623                  * but have application data.  If the library was
1624                  * running inside ssl3_read() (i.e. in_read_app_data
1625                  * is set) and it makes sense to read application data
1626                  * at this point (session renegotiation not yet started),
1627                  * we will indulge it.
1628                  */
1629                 if (s->s3->in_read_app_data &&
1630                         (s->s3->total_renegotiations != 0) &&
1631                         ((
1632                                 (s->state & SSL_ST_CONNECT) &&
1633                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1634                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1635                                 ) || (
1636                                         (s->state & SSL_ST_ACCEPT) &&
1637                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1638                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1639                                         )
1640                                 ))
1641                         {
1642                         s->s3->in_read_app_data=2;
1643                         return(-1);
1644                         }
1645                 else
1646                         {
1647                         al=SSL_AD_UNEXPECTED_MESSAGE;
1648                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1649                         goto f_err;
1650                         }
1651                 }
1652         /* not reached */
1653
1654 f_err:
1655         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1656 err:
1657         return(-1);
1658         }
1659
1660 int ssl3_do_change_cipher_spec(SSL *s)
1661         {
1662         int i;
1663         const char *sender;
1664         int slen;
1665
1666         if (s->state & SSL_ST_ACCEPT)
1667                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1668         else
1669                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1670
1671         if (s->s3->tmp.key_block == NULL)
1672                 {
1673                 if (s->session == NULL || s->session->master_key_length == 0)
1674                         {
1675                         /* might happen if dtls1_read_bytes() calls this */
1676                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1677                         return (0);
1678                         }
1679
1680                 s->session->cipher=s->s3->tmp.new_cipher;
1681                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1682                 }
1683
1684         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1685                 return(0);
1686
1687         /* we have to record the message digest at
1688          * this point so we can get it before we read
1689          * the finished message */
1690         if (s->state & SSL_ST_CONNECT)
1691                 {
1692                 sender=s->method->ssl3_enc->server_finished_label;
1693                 slen=s->method->ssl3_enc->server_finished_label_len;
1694                 }
1695         else
1696                 {
1697                 sender=s->method->ssl3_enc->client_finished_label;
1698                 slen=s->method->ssl3_enc->client_finished_label_len;
1699                 }
1700
1701         i = s->method->ssl3_enc->final_finish_mac(s,
1702                 sender,slen,s->s3->tmp.peer_finish_md);
1703         if (i == 0)
1704                 {
1705                 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
1706                 return 0;
1707                 }
1708         s->s3->tmp.peer_finish_md_len = i;
1709
1710         return(1);
1711         }
1712
1713 int ssl3_send_alert(SSL *s, int level, int desc)
1714         {
1715         /* Map tls/ssl alert value to correct one */
1716         desc=s->method->ssl3_enc->alert_value(desc);
1717         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1718                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1719         if (desc < 0) return -1;
1720         /* If a fatal one, remove from cache */
1721         if ((level == 2) && (s->session != NULL))
1722                 SSL_CTX_remove_session(s->ctx,s->session);
1723
1724         s->s3->alert_dispatch=1;
1725         s->s3->send_alert[0]=level;
1726         s->s3->send_alert[1]=desc;
1727         if (s->s3->wbuf.left == 0) /* data still being written out? */
1728                 return s->method->ssl_dispatch_alert(s);
1729         /* else data is still being written out, we will get written
1730          * some time in the future */
1731         return -1;
1732         }
1733
1734 int ssl3_dispatch_alert(SSL *s)
1735         {
1736         int i,j;
1737         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1738
1739         s->s3->alert_dispatch=0;
1740         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1741         if (i <= 0)
1742                 {
1743                 s->s3->alert_dispatch=1;
1744                 }
1745         else
1746                 {
1747                 /* Alert sent to BIO.  If it is important, flush it now.
1748                  * If the message does not get sent due to non-blocking IO,
1749                  * we will not worry too much. */
1750                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1751                         (void)BIO_flush(s->wbio);
1752
1753                 if (s->msg_callback)
1754                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1755
1756                 if (s->info_callback != NULL)
1757                         cb=s->info_callback;
1758                 else if (s->ctx->info_callback != NULL)
1759                         cb=s->ctx->info_callback;
1760
1761                 if (cb != NULL)
1762                         {
1763                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1764                         cb(s,SSL_CB_WRITE_ALERT,j);
1765                         }
1766                 }
1767         return(i);
1768         }