ssl/s3_pkt.c

   1 /* ssl/s3_pkt.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58 /* ====================================================================
  59  * Copyright (c) 1998-2002 The OpenSSL Project.  All rights reserved.
  60  *
  61  * Redistribution and use in source and binary forms, with or without
  62  * modification, are permitted provided that the following conditions
  63  * are met:
  64  *
  65  * 1. Redistributions of source code must retain the above copyright
  66  *    notice, this list of conditions and the following disclaimer.
  67  *
  68  * 2. Redistributions in binary form must reproduce the above copyright
  69  *    notice, this list of conditions and the following disclaimer in
  70  *    the documentation and/or other materials provided with the
  71  *    distribution.
  72  *
  73  * 3. All advertising materials mentioning features or use of this
  74  *    software must display the following acknowledgment:
  75  *    "This product includes software developed by the OpenSSL Project
  76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  77  *
  78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  79  *    endorse or promote products derived from this software without
  80  *    prior written permission. For written permission, please contact
  81  *    openssl-core@openssl.org.
  82  *
  83  * 5. Products derived from this software may not be called "OpenSSL"
  84  *    nor may "OpenSSL" appear in their names without prior written
  85  *    permission of the OpenSSL Project.
  86  *
  87  * 6. Redistributions of any form whatsoever must retain the following
  88  *    acknowledgment:
  89  *    "This product includes software developed by the OpenSSL Project
  90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  91  *
  92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 103  * OF THE POSSIBILITY OF SUCH DAMAGE.
 104  * ====================================================================
 105  *
 106  * This product includes cryptographic software written by Eric Young
 107  * (eay@cryptsoft.com).  This product includes software written by Tim
 108  * Hudson (tjh@cryptsoft.com).
 109  *
 110  */
 111
 112 #include <stdio.h>
 113 #include <errno.h>
 114 #define USE_SOCKETS
 115 #include "ssl_locl.h"
 116 #include <openssl/evp.h>
 117 #include <openssl/buffer.h>
 118 #include <openssl/rand.h>
 119
 120 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 121                          unsigned int len, int create_empty_fragment);
 122 static int ssl3_get_record(SSL *s);
 123
 124 int ssl3_read_n(SSL *s, int n, int max, int extend)
 125         {
 126         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
 127          * packet by another n bytes.
 128          * The packet will be in the sub-array of s->s3->rbuf.buf specified
 129          * by s->packet and s->packet_length.
 130          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
 131          * [plus s->packet_length bytes if extend == 1].)
 132          */
 133         int i,len,left;
 134         long align=0;
 135         unsigned char *pkt;
 136         SSL3_BUFFER *rb;
 137
 138         if (n <= 0) return n;
 139
 140         rb    = &(s->s3->rbuf);
 141         if (rb->buf == NULL)
 142                 if (!ssl3_setup_read_buffer(s))
 143                         return -1;
 144
 145         left  = rb->left;
 146 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
 147         align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
 148         align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
 149 #endif
 150
 151         if (!extend)
 152                 {
 153                 /* start with empty packet ... */
 154                 if (left == 0)
 155                         rb->offset = align;
 156                 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
 157                         {
 158                         /* check if next packet length is large
 159                          * enough to justify payload alignment... */
 160                         pkt = rb->buf + rb->offset;
 161                         if (pkt[0] == SSL3_RT_APPLICATION_DATA
 162                             && (pkt[3]<<8|pkt[4]) >= 128)
 163                                 {
 164                                 /* Note that even if packet is corrupted
 165                                  * and its length field is insane, we can
 166                                  * only be led to wrong decision about
 167                                  * whether memmove will occur or not.
 168                                  * Header values has no effect on memmove
 169                                  * arguments and therefore no buffer
 170                                  * overrun can be triggered. */
 171                                 memmove (rb->buf+align,pkt,left);
 172                                 rb->offset = align;
 173                                 }
 174                         }
 175                 s->packet = rb->buf + rb->offset;
 176                 s->packet_length = 0;
 177                 /* ... now we can act as if 'extend' was set */
 178                 }
 179
 180         /* For DTLS/UDP reads should not span multiple packets
 181          * because the read operation returns the whole packet
 182          * at once (as long as it fits into the buffer). */
 183         if (SSL_IS_DTLS(s))
 184                 {
 185                 if (left > 0 && n > left)
 186                         n = left;
 187                 }
 188
 189         /* if there is enough in the buffer from a previous read, take some */
 190         if (left >= n)
 191                 {
 192                 s->packet_length+=n;
 193                 rb->left=left-n;
 194                 rb->offset+=n;
 195                 return(n);
 196                 }
 197
 198         /* else we need to read more data */
 199
 200         len = s->packet_length;
 201         pkt = rb->buf+align;
 202         /* Move any available bytes to front of buffer:
 203          * 'len' bytes already pointed to by 'packet',
 204          * 'left' extra ones at the end */
 205         if (s->packet != pkt) /* len > 0 */
 206                 {
 207                 memmove(pkt, s->packet, len+left);
 208                 s->packet = pkt;
 209                 rb->offset = len + align;
 210                 }
 211
 212         if (n > (int)(rb->len - rb->offset)) /* does not happen */
 213                 {
 214                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 215                 return -1;
 216                 }
 217
 218         if (!s->read_ahead)
 219                 /* ignore max parameter */
 220                 max = n;
 221         else
 222                 {
 223                 if (max < n)
 224                         max = n;
 225                 if (max > (int)(rb->len - rb->offset))
 226                         max = rb->len - rb->offset;
 227                 }
 228
 229         while (left < n)
 230                 {
 231                 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
 232                  * and need to read in more until we have len+n (up to
 233                  * len+max if possible) */
 234
 235                 clear_sys_error();
 236                 if (s->rbio != NULL)
 237                         {
 238                         s->rwstate=SSL_READING;
 239                         i=BIO_read(s->rbio,pkt+len+left, max-left);
 240                         }
 241                 else
 242                         {
 243                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 244                         i = -1;
 245                         }
 246
 247                 if (i <= 0)
 248                         {
 249                         rb->left = left;
 250                         if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
 251                                 !SSL_IS_DTLS(s))
 252                                 if (len+left == 0)
 253                                         ssl3_release_read_buffer(s);
 254                         return(i);
 255                         }
 256                 left+=i;
 257                 /* reads should *never* span multiple packets for DTLS because
 258                  * the underlying transport protocol is message oriented as opposed
 259                  * to byte oriented as in the TLS case. */
 260                 if (SSL_IS_DTLS(s))
 261                         {
 262                         if (n > left)
 263                                 n = left; /* makes the while condition false */
 264                         }
 265                 }
 266
 267         /* done reading, now the book-keeping */
 268         rb->offset += n;
 269         rb->left = left - n;
 270         s->packet_length += n;
 271         s->rwstate=SSL_NOTHING;
 272         return(n);
 273         }
 274
 275 /* Call this to get a new input record.
 276  * It will return <= 0 if more data is needed, normally due to an error
 277  * or non-blocking IO.
 278  * When it finishes, one packet has been decoded and can be found in
 279  * ssl->s3->rrec.type    - is the type of record
 280  * ssl->s3->rrec.data,   - data
 281  * ssl->s3->rrec.length, - number of bytes
 282  */
 283 /* used only by ssl3_read_bytes */
 284 static int ssl3_get_record(SSL *s)
 285         {
 286         int ssl_major,ssl_minor,al;
 287         int enc_err,n,i,ret= -1;
 288         SSL3_RECORD *rr;
 289         SSL_SESSION *sess;
 290         unsigned char *p;
 291         unsigned char md[EVP_MAX_MD_SIZE];
 292         short version;
 293         unsigned mac_size, orig_len;
 294         size_t extra;
 295
 296         rr= &(s->s3->rrec);
 297         sess=s->session;
 298
 299         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 300                 extra=SSL3_RT_MAX_EXTRA;
 301         else
 302                 extra=0;
 303         if (extra && !s->s3->init_extra)
 304                 {
 305                 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
 306                  * set after ssl3_setup_buffers() was done */
 307                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
 308                 return -1;
 309                 }
 310
 311 again:
 312         /* check if we have the header */
 313         if (    (s->rstate != SSL_ST_READ_BODY) ||
 314                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 315                 {
 316                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 317                 if (n <= 0) return(n); /* error or non-blocking */
 318                 s->rstate=SSL_ST_READ_BODY;
 319
 320                 p=s->packet;
 321                 if (s->msg_callback)
 322                         s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s, s->msg_callback_arg);
 323
 324                 /* Pull apart the header into the SSL3_RECORD */
 325                 rr->type= *(p++);
 326                 ssl_major= *(p++);
 327                 ssl_minor= *(p++);
 328                 version=(ssl_major<<8)|ssl_minor;
 329                 n2s(p,rr->length);
 330 #if 0
 331 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
 332 #endif
 333
 334                 /* Lets check version */
 335                 if (!s->first_packet)
 336                         {
 337                         if (version != s->version)
 338                                 {
 339                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 340                                 if ((s->version & 0xFF00) == (version & 0xFF00))
 341                                         /* Send back error using their minor version number :-) */
 342                                         s->version = (unsigned short)version;
 343                                 al=SSL_AD_PROTOCOL_VERSION;
 344                                 goto f_err;
 345                                 }
 346                         }
 347
 348                 if ((version>>8) != SSL3_VERSION_MAJOR)
 349                         {
 350                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 351                         goto err;
 352                         }
 353
 354                 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
 355                         {
 356                         al=SSL_AD_RECORD_OVERFLOW;
 357                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 358                         goto f_err;
 359                         }
 360
 361                 /* now s->rstate == SSL_ST_READ_BODY */
 362                 }
 363
 364         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 365
 366         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
 367                 {
 368                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
 369                 i=rr->length;
 370                 n=ssl3_read_n(s,i,i,1);
 371                 if (n <= 0) return(n); /* error or non-blocking io */
 372                 /* now n == rr->length,
 373                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
 374                 }
 375
 376         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 377
 378         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 379          * and we have that many bytes in s->packet
 380          */
 381         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 382
 383         /* ok, we can now read from 's->packet' data into 'rr'
 384          * rr->input points at rr->length bytes, which
 385          * need to be copied into rr->data by either
 386          * the decryption or by the decompression
 387          * When the data is 'copied' into the rr->data buffer,
 388          * rr->input will be pointed at the new buffer */
 389
 390         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 391          * rr->length bytes of encrypted compressed stuff. */
 392
 393         /* check is not needed I believe */
 394         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 395                 {
 396                 al=SSL_AD_RECORD_OVERFLOW;
 397                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 398                 goto f_err;
 399                 }
 400
 401         /* decrypt in place in 'rr->input' */
 402         rr->data=rr->input;
 403
 404         enc_err = s->method->ssl3_enc->enc(s,0);
 405         /* enc_err is:
 406          *    0: (in non-constant time) if the record is publically invalid.
 407          *    1: if the padding is valid
 408          *    -1: if the padding is invalid */
 409         if (enc_err == 0)
 410                 {
 411                 al=SSL_AD_DECRYPTION_FAILED;
 412                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
 413                 goto f_err;
 414                 }
 415
 416 #ifdef TLS_DEBUG
 417 printf("dec %d\n",rr->length);
 418 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 419 printf("\n");
 420 #endif
 421
 422         /* r->length is now the compressed data plus mac */
 423         if ((sess != NULL) &&
 424             (s->enc_read_ctx != NULL) &&
 425             (EVP_MD_CTX_md(s->read_hash) != NULL))
 426                 {
 427                 /* s->read_hash != NULL => mac_size != -1 */
 428                 unsigned char *mac = NULL;
 429                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 430                 mac_size=EVP_MD_CTX_size(s->read_hash);
 431                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 432
 433                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 434                 orig_len = rr->length+((unsigned int)rr->type>>8);
 435
 436                 /* orig_len is the length of the record before any padding was
 437                  * removed. This is public information, as is the MAC in use,
 438                  * therefore we can safely process the record in a different
 439                  * amount of time if it's too short to possibly contain a MAC.
 440                  */
 441                 if (orig_len < mac_size ||
 442                     /* CBC records must have a padding length byte too. */
 443                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 444                      orig_len < mac_size+1))
 445                         {
 446                         al=SSL_AD_DECODE_ERROR;
 447                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 448                         goto f_err;
 449                         }
 450
 451                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 452                         {
 453                         /* We update the length so that the TLS header bytes
 454                          * can be constructed correctly but we need to extract
 455                          * the MAC in constant time from within the record,
 456                          * without leaking the contents of the padding bytes.
 457                          * */
 458                         mac = mac_tmp;
 459                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 460                         rr->length -= mac_size;
 461                         }
 462                 else
 463                         {
 464                         /* In this case there's no padding, so |orig_len|
 465                          * equals |rec->length| and we checked that there's
 466                          * enough bytes for |mac_size| above. */
 467                         rr->length -= mac_size;
 468                         mac = &rr->data[rr->length];
 469                         }
 470
 471                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 472                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 473                         enc_err = -1;
 474                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 475                         enc_err = -1;
 476                 }
 477
 478         if (enc_err < 0)
 479                 {
 480                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
 481                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
 482                  * failure is directly visible from the ciphertext anyway,
 483                  * we should not reveal which kind of error occured -- this
 484                  * might become visible to an attacker (e.g. via a logfile) */
 485                 al=SSL_AD_BAD_RECORD_MAC;
 486                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
 487                 goto f_err;
 488                 }
 489
 490         /* r->length is now just compressed */
 491         if (s->expand != NULL)
 492                 {
 493                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 494                         {
 495                         al=SSL_AD_RECORD_OVERFLOW;
 496                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 497                         goto f_err;
 498                         }
 499                 if (!ssl3_do_uncompress(s))
 500                         {
 501                         al=SSL_AD_DECOMPRESSION_FAILURE;
 502                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 503                         goto f_err;
 504                         }
 505                 }
 506
 507         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
 508                 {
 509                 al=SSL_AD_RECORD_OVERFLOW;
 510                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 511                 goto f_err;
 512                 }
 513
 514         rr->off=0;
 515         /* So at this point the following is true
 516          * ssl->s3->rrec.type   is the type of record
 517          * ssl->s3->rrec.length == number of bytes in record
 518          * ssl->s3->rrec.off    == offset to first valid byte
 519          * ssl->s3->rrec.data   == where to take bytes from, increment
 520          *                         after use :-).
 521          */
 522
 523         /* we have pulled in a full packet so zero things */
 524         s->packet_length=0;
 525
 526         /* just read a 0 length packet */
 527         if (rr->length == 0) goto again;
 528
 529 #if 0
 530 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
 531 #endif
 532
 533         return(1);
 534
 535 f_err:
 536         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 537 err:
 538         return(ret);
 539         }
 540
 541 int ssl3_do_uncompress(SSL *ssl)
 542         {
 543 #ifndef OPENSSL_NO_COMP
 544         int i;
 545         SSL3_RECORD *rr;
 546
 547         rr= &(ssl->s3->rrec);
 548         i=COMP_expand_block(ssl->expand,rr->comp,
 549                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 550         if (i < 0)
 551                 return(0);
 552         else
 553                 rr->length=i;
 554         rr->data=rr->comp;
 555 #endif
 556         return(1);
 557         }
 558
 559 int ssl3_do_compress(SSL *ssl)
 560         {
 561 #ifndef OPENSSL_NO_COMP
 562         int i;
 563         SSL3_RECORD *wr;
 564
 565         wr= &(ssl->s3->wrec);
 566         i=COMP_compress_block(ssl->compress,wr->data,
 567                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 568                 wr->input,(int)wr->length);
 569         if (i < 0)
 570                 return(0);
 571         else
 572                 wr->length=i;
 573
 574         wr->input=wr->data;
 575 #endif
 576         return(1);
 577         }
 578
 579 /* Call this to write data in records of type 'type'
 580  * It will return <= 0 if not all data has been sent or non-blocking IO.
 581  */
 582 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 583         {
 584         const unsigned char *buf=buf_;
 585         unsigned int tot,n,nw;
 586         int i;
 587
 588         s->rwstate=SSL_NOTHING;
 589         tot=s->s3->wnum;
 590         s->s3->wnum=0;
 591
 592         if (SSL_in_init(s) && !s->in_handshake)
 593                 {
 594                 i=s->handshake_func(s);
 595                 if (i < 0) return(i);
 596                 if (i == 0)
 597                         {
 598                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 599                         return -1;
 600                         }
 601                 }
 602
 603         n=(len-tot);
 604         for (;;)
 605                 {
 606                 if (n > s->max_send_fragment)
 607                         nw=s->max_send_fragment;
 608                 else
 609                         nw=n;
 610
 611                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
 612                 if (i <= 0)
 613                         {
 614                         s->s3->wnum=tot;
 615                         return i;
 616                         }
 617
 618                 if ((i == (int)n) ||
 619                         (type == SSL3_RT_APPLICATION_DATA &&
 620                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 621                         {
 622                         /* next chunk of data should get another prepended empty fragment
 623                          * in ciphersuites with known-IV weakness: */
 624                         s->s3->empty_fragment_done = 0;
 625
 626                         return tot+i;
 627                         }
 628
 629                 n-=i;
 630                 tot+=i;
 631                 }
 632         }
 633
 634 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 635                          unsigned int len, int create_empty_fragment)
 636         {
 637         unsigned char *p,*plen;
 638         int i,mac_size,clear=0;
 639         int prefix_len=0;
 640         int eivlen;
 641         long align=0;
 642         SSL3_RECORD *wr;
 643         SSL3_BUFFER *wb=&(s->s3->wbuf);
 644         SSL_SESSION *sess;
 645
 646         if (wb->buf == NULL)
 647                 if (!ssl3_setup_write_buffer(s))
 648                         return -1;
 649
 650         /* first check if there is a SSL3_BUFFER still being written
 651          * out.  This will happen with non blocking IO */
 652         if (wb->left != 0)
 653                 return(ssl3_write_pending(s,type,buf,len));
 654
 655         /* If we have an alert to send, lets send it */
 656         if (s->s3->alert_dispatch)
 657                 {
 658                 i=s->method->ssl_dispatch_alert(s);
 659                 if (i <= 0)
 660                         return(i);
 661                 /* if it went, fall through and send more stuff */
 662                 }
 663
 664         if (len == 0 && !create_empty_fragment)
 665                 return 0;
 666
 667         wr= &(s->s3->wrec);
 668         sess=s->session;
 669
 670         if (    (sess == NULL) ||
 671                 (s->enc_write_ctx == NULL) ||
 672                 (EVP_MD_CTX_md(s->write_hash) == NULL))
 673                 {
 674 #if 1
 675                 clear=s->enc_write_ctx?0:1;     /* must be AEAD cipher */
 676 #else
 677                 clear=1;
 678 #endif
 679                 mac_size=0;
 680                 }
 681         else
 682                 {
 683                 mac_size=EVP_MD_CTX_size(s->write_hash);
 684                 if (mac_size < 0)
 685                         goto err;
 686                 }
 687
 688         /* 'create_empty_fragment' is true only when this function calls itself */
 689         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
 690                 {
 691                 /* countermeasure against known-IV weakness in CBC ciphersuites
 692                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
 693
 694                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
 695                         {
 696                         /* recursive function call with 'create_empty_fragment' set;
 697                          * this prepares and buffers the data for an empty fragment
 698                          * (these 'prefix_len' bytes are sent out later
 699                          * together with the actual payload) */
 700                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
 701                         if (prefix_len <= 0)
 702                                 goto err;
 703
 704                         if (prefix_len >
 705                 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
 706                                 {
 707                                 /* insufficient space */
 708                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
 709                                 goto err;
 710                                 }
 711                         }
 712
 713                 s->s3->empty_fragment_done = 1;
 714                 }
 715
 716         if (create_empty_fragment)
 717                 {
 718 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
 719                 /* extra fragment would be couple of cipher blocks,
 720                  * which would be multiple of SSL3_ALIGN_PAYLOAD, so
 721                  * if we want to align the real payload, then we can
 722                  * just pretent we simply have two headers. */
 723                 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
 724                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
 725 #endif
 726                 p = wb->buf + align;
 727                 wb->offset  = align;
 728                 }
 729         else if (prefix_len)
 730                 {
 731                 p = wb->buf + wb->offset + prefix_len;
 732                 }
 733         else
 734                 {
 735 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
 736                 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
 737                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
 738 #endif
 739                 p = wb->buf + align;
 740                 wb->offset  = align;
 741                 }
 742
 743         /* write the header */
 744
 745         *(p++)=type&0xff;
 746         wr->type=type;
 747
 748         *(p++)=(s->version>>8);
 749         /* Some servers hang if iniatial client hello is larger than 256
 750          * bytes and record version number > TLS 1.0
 751          */
 752         if (s->state == SSL3_ST_CW_CLNT_HELLO_B
 753                                 && !s->renegotiate
 754                                 && TLS1_get_version(s) > TLS1_VERSION)
 755                 *(p++) = 0x1;
 756         else
 757                 *(p++)=s->version&0xff;
 758
 759         /* field where we are to write out packet length */
 760         plen=p;
 761         p+=2;
 762         /* Explicit IV length, block ciphers appropriate version flag */
 763         if (s->enc_write_ctx && SSL_USE_EXPLICIT_IV(s))
 764                 {
 765                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
 766                 if (mode == EVP_CIPH_CBC_MODE)
 767                         {
 768                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
 769                         if (eivlen <= 1)
 770                                 eivlen = 0;
 771                         }
 772                 /* Need explicit part of IV for GCM mode */
 773                 else if (mode == EVP_CIPH_GCM_MODE)
 774                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
 775                 else
 776                         eivlen = 0;
 777                 }
 778         else if (s->aead_write_ctx != NULL &&
 779                  s->aead_write_ctx->variable_nonce_included_in_record)
 780                 {
 781                 eivlen = s->aead_write_ctx->variable_nonce_len;
 782                 }
 783         else
 784                 eivlen = 0;
 785
 786         /* lets setup the record stuff. */
 787         wr->data=p + eivlen;
 788         wr->length=(int)len;
 789         wr->input=(unsigned char *)buf;
 790
 791         /* we now 'read' from wr->input, wr->length bytes into
 792          * wr->data */
 793
 794         /* first we compress */
 795         if (s->compress != NULL)
 796                 {
 797                 if (!ssl3_do_compress(s))
 798                         {
 799                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 800                         goto err;
 801                         }
 802                 }
 803         else
 804                 {
 805                 memcpy(wr->data,wr->input,wr->length);
 806                 wr->input=wr->data;
 807                 }
 808
 809         /* we should still have the output to wr->data and the input
 810          * from wr->input.  Length should be wr->length.
 811          * wr->data still points in the wb->buf */
 812
 813         if (mac_size != 0)
 814                 {
 815                 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
 816                         goto err;
 817                 wr->length+=mac_size;
 818                 }
 819
 820         wr->input=p;
 821         wr->data=p;
 822
 823         if (eivlen)
 824                 {
 825         /*      if (RAND_pseudo_bytes(p, eivlen) <= 0)
 826                         goto err; */
 827                 wr->length += eivlen;
 828                 }
 829
 830         /* ssl3_enc can only have an error on read */
 831         s->method->ssl3_enc->enc(s,1);
 832
 833         /* record length after mac and block padding */
 834         s2n(wr->length,plen);
 835
 836         if (s->msg_callback)
 837                 s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s, s->msg_callback_arg);
 838
 839         /* we should now have
 840          * wr->data pointing to the encrypted data, which is
 841          * wr->length long */
 842         wr->type=type; /* not needed but helps for debugging */
 843         wr->length+=SSL3_RT_HEADER_LENGTH;
 844
 845         if (create_empty_fragment)
 846                 {
 847                 /* we are in a recursive call;
 848                  * just return the length, don't write out anything here
 849                  */
 850                 return wr->length;
 851                 }
 852
 853         /* now let's set up wb */
 854         wb->left = prefix_len + wr->length;
 855
 856         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
 857         s->s3->wpend_tot=len;
 858         s->s3->wpend_buf=buf;
 859         s->s3->wpend_type=type;
 860         s->s3->wpend_ret=len;
 861
 862         /* we now just need to write the buffer */
 863         return ssl3_write_pending(s,type,buf,len);
 864 err:
 865         return -1;
 866         }
 867
 868 /* if s->s3->wbuf.left != 0, we need to call this */
 869 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 870         unsigned int len)
 871         {
 872         int i;
 873         SSL3_BUFFER *wb=&(s->s3->wbuf);
 874
 875 /* XXXX */
 876         if ((s->s3->wpend_tot > (int)len)
 877                 || ((s->s3->wpend_buf != buf) &&
 878                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 879                 || (s->s3->wpend_type != type))
 880                 {
 881                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 882                 return(-1);
 883                 }
 884
 885         for (;;)
 886                 {
 887                 clear_sys_error();
 888                 if (s->wbio != NULL)
 889                         {
 890                         s->rwstate=SSL_WRITING;
 891                         i=BIO_write(s->wbio,
 892                                 (char *)&(wb->buf[wb->offset]),
 893                                 (unsigned int)wb->left);
 894                         }
 895                 else
 896                         {
 897                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 898                         i= -1;
 899                         }
 900                 if (i == wb->left)
 901                         {
 902                         wb->left=0;
 903                         wb->offset+=i;
 904                         if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
 905                                 !SSL_IS_DTLS(s))
 906                                 ssl3_release_write_buffer(s);
 907                         s->rwstate=SSL_NOTHING;
 908                         return(s->s3->wpend_ret);
 909                         }
 910                 else if (i <= 0) {
 911                         if (s->version == DTLS1_VERSION ||
 912                             s->version == DTLS1_BAD_VER) {
 913                                 /* For DTLS, just drop it. That's kind of the whole
 914                                    point in using a datagram service */
 915                                 wb->left = 0;
 916                         }
 917                         return(i);
 918                 }
 919                 wb->offset+=i;
 920                 wb->left-=i;
 921                 }
 922         }
 923
 924 /* Return up to 'len' payload bytes received in 'type' records.
 925  * 'type' is one of the following:
 926  *
 927  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 928  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 929  *   -  0 (during a shutdown, no data has to be returned)
 930  *
 931  * If we don't have stored data to work from, read a SSL/TLS record first
 932  * (possibly multiple records if we still don't have anything to return).
 933  *
 934  * This function must handle any surprises the peer may have for us, such as
 935  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 936  * a surprise, but handled as if it were), or renegotiation requests.
 937  * Also if record payloads contain fragments too small to process, we store
 938  * them until there is enough for the respective protocol (the record protocol
 939  * may use arbitrary fragmentation and even interleaving):
 940  *     Change cipher spec protocol
 941  *             just 1 byte needed, no need for keeping anything stored
 942  *     Alert protocol
 943  *             2 bytes needed (AlertLevel, AlertDescription)
 944  *     Handshake protocol
 945  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 946  *             to detect unexpected Client Hello and Hello Request messages
 947  *             here, anything else is handled by higher layers
 948  *     Application data protocol
 949  *             none of our business
 950  */
 951 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 952         {
 953         int al,i,j,ret;
 954         unsigned int n;
 955         SSL3_RECORD *rr;
 956         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 957
 958         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 959                 if (!ssl3_setup_read_buffer(s))
 960                         return(-1);
 961
 962         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
 963             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 964                 {
 965                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
 966                 return -1;
 967                 }
 968
 969         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 970                 /* (partially) satisfy request from storage */
 971                 {
 972                 unsigned char *src = s->s3->handshake_fragment;
 973                 unsigned char *dst = buf;
 974                 unsigned int k;
 975
 976                 /* peek == 0 */
 977                 n = 0;
 978                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 979                         {
 980                         *dst++ = *src++;
 981                         len--; s->s3->handshake_fragment_len--;
 982                         n++;
 983                         }
 984                 /* move any remaining fragment bytes: */
 985                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
 986                         s->s3->handshake_fragment[k] = *src++;
 987                 return n;
 988         }
 989
 990         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 991
 992         if (!s->in_handshake && SSL_in_init(s))
 993                 {
 994                 /* type == SSL3_RT_APPLICATION_DATA */
 995                 i=s->handshake_func(s);
 996                 if (i < 0) return(i);
 997                 if (i == 0)
 998                         {
 999                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1000                         return(-1);
1001                         }
1002                 }
1003 start:
1004         s->rwstate=SSL_NOTHING;
1005
1006         /* s->s3->rrec.type         - is the type of record
1007          * s->s3->rrec.data,    - data
1008          * s->s3->rrec.off,     - offset into 'data' for next read
1009          * s->s3->rrec.length,  - number of bytes. */
1010         rr = &(s->s3->rrec);
1011
1012         /* get new packet if necessary */
1013         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1014                 {
1015                 ret=ssl3_get_record(s);
1016                 if (ret <= 0) return(ret);
1017                 }
1018
1019         /* we now have a packet which can be read and processed */
1020
1021         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1022                                        * reset by ssl3_get_finished */
1023                 && (rr->type != SSL3_RT_HANDSHAKE))
1024                 {
1025                 al=SSL_AD_UNEXPECTED_MESSAGE;
1026                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1027                 goto f_err;
1028                 }
1029
1030         /* If the other end has shut down, throw anything we read away
1031          * (even in 'peek' mode) */
1032         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1033                 {
1034                 rr->length=0;
1035                 s->rwstate=SSL_NOTHING;
1036                 return(0);
1037                 }
1038
1039
1040         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1041                 {
1042                 /* make sure that we are not getting application data when we
1043                  * are doing a handshake for the first time */
1044                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1045                         (s->enc_read_ctx == NULL))
1046                         {
1047                         al=SSL_AD_UNEXPECTED_MESSAGE;
1048                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1049                         goto f_err;
1050                         }
1051
1052                 if (len <= 0) return(len);
1053
1054                 if ((unsigned int)len > rr->length)
1055                         n = rr->length;
1056                 else
1057                         n = (unsigned int)len;
1058
1059                 memcpy(buf,&(rr->data[rr->off]),n);
1060                 if (!peek)
1061                         {
1062                         rr->length-=n;
1063                         rr->off+=n;
1064                         if (rr->length == 0)
1065                                 {
1066                                 s->rstate=SSL_ST_READ_HEADER;
1067                                 rr->off=0;
1068                                 if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1069                                         ssl3_release_read_buffer(s);
1070                                 }
1071                         }
1072                 return(n);
1073                 }
1074
1075
1076         /* If we get here, then type != rr->type; if we have a handshake
1077          * message, then it was unexpected (Hello Request or Client Hello). */
1078
1079         /* In case of record types for which we have 'fragment' storage,
1080          * fill that so that we can process the data at a fixed place.
1081          */
1082                 {
1083                 unsigned int dest_maxlen = 0;
1084                 unsigned char *dest = NULL;
1085                 unsigned int *dest_len = NULL;
1086
1087                 if (rr->type == SSL3_RT_HANDSHAKE)
1088                         {
1089                         dest_maxlen = sizeof s->s3->handshake_fragment;
1090                         dest = s->s3->handshake_fragment;
1091                         dest_len = &s->s3->handshake_fragment_len;
1092                         }
1093                 else if (rr->type == SSL3_RT_ALERT)
1094                         {
1095                         dest_maxlen = sizeof s->s3->alert_fragment;
1096                         dest = s->s3->alert_fragment;
1097                         dest_len = &s->s3->alert_fragment_len;
1098                         }
1099 #ifndef OPENSSL_NO_HEARTBEATS
1100                 else if (rr->type == TLS1_RT_HEARTBEAT)
1101                         {
1102                         tls1_process_heartbeat(s);
1103
1104                         /* Exit and notify application to read again */
1105                         rr->length = 0;
1106                         s->rwstate=SSL_READING;
1107                         BIO_clear_retry_flags(SSL_get_rbio(s));
1108                         BIO_set_retry_read(SSL_get_rbio(s));
1109                         return(-1);
1110                         }
1111 #endif
1112
1113                 if (dest_maxlen > 0)
1114                         {
1115                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
1116                         if (rr->length < n)
1117                                 n = rr->length; /* available bytes */
1118
1119                         /* now move 'n' bytes: */
1120                         while (n-- > 0)
1121                                 {
1122                                 dest[(*dest_len)++] = rr->data[rr->off++];
1123                                 rr->length--;
1124                                 }
1125
1126                         if (*dest_len < dest_maxlen)
1127                                 goto start; /* fragment was too small */
1128                         }
1129                 }
1130
1131         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1132          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1133          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1134
1135         /* If we are a client, check for an incoming 'Hello Request': */
1136         if ((!s->server) &&
1137                 (s->s3->handshake_fragment_len >= 4) &&
1138                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1139                 (s->session != NULL) && (s->session->cipher != NULL))
1140                 {
1141                 s->s3->handshake_fragment_len = 0;
1142
1143                 if ((s->s3->handshake_fragment[1] != 0) ||
1144                         (s->s3->handshake_fragment[2] != 0) ||
1145                         (s->s3->handshake_fragment[3] != 0))
1146                         {
1147                         al=SSL_AD_DECODE_ERROR;
1148                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1149                         goto f_err;
1150                         }
1151
1152                 if (s->msg_callback)
1153                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1154
1155                 if (SSL_is_init_finished(s) &&
1156                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1157                         !s->s3->renegotiate)
1158                         {
1159                         ssl3_renegotiate(s);
1160                         if (ssl3_renegotiate_check(s))
1161                                 {
1162                                 i=s->handshake_func(s);
1163                                 if (i < 0) return(i);
1164                                 if (i == 0)
1165                                         {
1166                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1167                                         return(-1);
1168                                         }
1169
1170                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1171                                         {
1172                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1173                                                 {
1174                                                 BIO *bio;
1175                                                 /* In the case where we try to read application data,
1176                                                  * but we trigger an SSL handshake, we return -1 with
1177                                                  * the retry option set.  Otherwise renegotiation may
1178                                                  * cause nasty problems in the blocking world */
1179                                                 s->rwstate=SSL_READING;
1180                                                 bio=SSL_get_rbio(s);
1181                                                 BIO_clear_retry_flags(bio);
1182                                                 BIO_set_retry_read(bio);
1183                                                 return(-1);
1184                                                 }
1185                                         }
1186                                 }
1187                         }
1188                 /* we either finished a handshake or ignored the request,
1189                  * now try again to obtain the (application) data we were asked for */
1190                 goto start;
1191                 }
1192         /* If we are a server and get a client hello when renegotiation isn't
1193          * allowed send back a no renegotiation alert and carry on.
1194          * WARNING: experimental code, needs reviewing (steve)
1195          */
1196         if (s->server &&
1197                 SSL_is_init_finished(s) &&
1198                 !s->s3->send_connection_binding &&
1199                 (s->version > SSL3_VERSION) &&
1200                 (s->s3->handshake_fragment_len >= 4) &&
1201                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1202                 (s->session != NULL) && (s->session->cipher != NULL) &&
1203                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1204
1205                 {
1206                 /*s->s3->handshake_fragment_len = 0;*/
1207                 rr->length = 0;
1208                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1209                 goto start;
1210                 }
1211         if (s->s3->alert_fragment_len >= 2)
1212                 {
1213                 int alert_level = s->s3->alert_fragment[0];
1214                 int alert_descr = s->s3->alert_fragment[1];
1215
1216                 s->s3->alert_fragment_len = 0;
1217
1218                 if (s->msg_callback)
1219                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1220
1221                 if (s->info_callback != NULL)
1222                         cb=s->info_callback;
1223                 else if (s->ctx->info_callback != NULL)
1224                         cb=s->ctx->info_callback;
1225
1226                 if (cb != NULL)
1227                         {
1228                         j = (alert_level << 8) | alert_descr;
1229                         cb(s, SSL_CB_READ_ALERT, j);
1230                         }
1231
1232                 if (alert_level == 1) /* warning */
1233                         {
1234                         s->s3->warn_alert = alert_descr;
1235                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1236                                 {
1237                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1238                                 return(0);
1239                                 }
1240                         /* This is a warning but we receive it if we requested
1241                          * renegotiation and the peer denied it. Terminate with
1242                          * a fatal alert because if application tried to
1243                          * renegotiatie it presumably had a good reason and
1244                          * expects it to succeed.
1245                          *
1246                          * In future we might have a renegotiation where we
1247                          * don't care if the peer refused it where we carry on.
1248                          */
1249                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1250                                 {
1251                                 al = SSL_AD_HANDSHAKE_FAILURE;
1252                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1253                                 goto f_err;
1254                                 }
1255 #ifdef SSL_AD_MISSING_SRP_USERNAME
1256                         else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1257                                 return(0);
1258 #endif
1259                         }
1260                 else if (alert_level == 2) /* fatal */
1261                         {
1262                         char tmp[16];
1263
1264                         s->rwstate=SSL_NOTHING;
1265                         s->s3->fatal_alert = alert_descr;
1266                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1267                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1268                         ERR_add_error_data(2,"SSL alert number ",tmp);
1269                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1270                         SSL_CTX_remove_session(s->ctx,s->session);
1271                         return(0);
1272                         }
1273                 else
1274                         {
1275                         al=SSL_AD_ILLEGAL_PARAMETER;
1276                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1277                         goto f_err;
1278                         }
1279
1280                 goto start;
1281                 }
1282
1283         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1284                 {
1285                 s->rwstate=SSL_NOTHING;
1286                 rr->length=0;
1287                 return(0);
1288                 }
1289
1290         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1291                 {
1292                 /* 'Change Cipher Spec' is just a single byte, so we know
1293                  * exactly what the record payload has to look like */
1294                 if (    (rr->length != 1) || (rr->off != 0) ||
1295                         (rr->data[0] != SSL3_MT_CCS))
1296                         {
1297                         al=SSL_AD_ILLEGAL_PARAMETER;
1298                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1299                         goto f_err;
1300                         }
1301
1302                 /* Check we have a cipher to change to */
1303                 if (s->s3->tmp.new_cipher == NULL)
1304                         {
1305                         al=SSL_AD_UNEXPECTED_MESSAGE;
1306                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1307                         goto f_err;
1308                         }
1309
1310                 rr->length=0;
1311
1312                 if (s->msg_callback)
1313                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1314
1315                 s->s3->change_cipher_spec=1;
1316                 if (!ssl3_do_change_cipher_spec(s))
1317                         goto err;
1318                 else
1319                         goto start;
1320                 }
1321
1322         /* Unexpected handshake message (Client Hello, or protocol violation) */
1323         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1324                 {
1325                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1326                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1327                         {
1328 #if 0 /* worked only because C operator preferences are not as expected (and
1329        * because this is not really needed for clients except for detecting
1330        * protocol violations): */
1331                         s->state=SSL_ST_BEFORE|(s->server)
1332                                 ?SSL_ST_ACCEPT
1333                                 :SSL_ST_CONNECT;
1334 #else
1335                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1336 #endif
1337                         s->renegotiate=1;
1338                         s->new_session=1;
1339                         }
1340                 i=s->handshake_func(s);
1341                 if (i < 0) return(i);
1342                 if (i == 0)
1343                         {
1344                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1345                         return(-1);
1346                         }
1347
1348                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1349                         {
1350                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1351                                 {
1352                                 BIO *bio;
1353                                 /* In the case where we try to read application data,
1354                                  * but we trigger an SSL handshake, we return -1 with
1355                                  * the retry option set.  Otherwise renegotiation may
1356                                  * cause nasty problems in the blocking world */
1357                                 s->rwstate=SSL_READING;
1358                                 bio=SSL_get_rbio(s);
1359                                 BIO_clear_retry_flags(bio);
1360                                 BIO_set_retry_read(bio);
1361                                 return(-1);
1362                                 }
1363                         }
1364                 goto start;
1365                 }
1366
1367         switch (rr->type)
1368                 {
1369         default:
1370 #ifndef OPENSSL_NO_TLS
1371                 /* TLS up to v1.1 just ignores unknown message types:
1372                  * TLS v1.2 give an unexpected message alert.
1373                  */
1374                 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1375                         {
1376                         rr->length = 0;
1377                         goto start;
1378                         }
1379 #endif
1380                 al=SSL_AD_UNEXPECTED_MESSAGE;
1381                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1382                 goto f_err;
1383         case SSL3_RT_CHANGE_CIPHER_SPEC:
1384         case SSL3_RT_ALERT:
1385         case SSL3_RT_HANDSHAKE:
1386                 /* we already handled all of these, with the possible exception
1387                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1388                  * should not happen when type != rr->type */
1389                 al=SSL_AD_UNEXPECTED_MESSAGE;
1390                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1391                 goto f_err;
1392         case SSL3_RT_APPLICATION_DATA:
1393                 /* At this point, we were expecting handshake data,
1394                  * but have application data.  If the library was
1395                  * running inside ssl3_read() (i.e. in_read_app_data
1396                  * is set) and it makes sense to read application data
1397                  * at this point (session renegotiation not yet started),
1398                  * we will indulge it.
1399                  */
1400                 if (s->s3->in_read_app_data &&
1401                         (s->s3->total_renegotiations != 0) &&
1402                         ((
1403                                 (s->state & SSL_ST_CONNECT) &&
1404                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1405                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1406                                 ) || (
1407                                         (s->state & SSL_ST_ACCEPT) &&
1408                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1409                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1410                                         )
1411                                 ))
1412                         {
1413                         s->s3->in_read_app_data=2;
1414                         return(-1);
1415                         }
1416                 else
1417                         {
1418                         al=SSL_AD_UNEXPECTED_MESSAGE;
1419                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1420                         goto f_err;
1421                         }
1422                 }
1423         /* not reached */
1424
1425 f_err:
1426         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1427 err:
1428         return(-1);
1429         }
1430
1431 int ssl3_do_change_cipher_spec(SSL *s)
1432         {
1433         int i;
1434         const char *sender;
1435         int slen;
1436
1437         if (s->state & SSL_ST_ACCEPT)
1438                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1439         else
1440                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1441
1442         if (s->s3->tmp.key_block == NULL)
1443                 {
1444                 if (s->session == NULL)
1445                         {
1446                         /* might happen if dtls1_read_bytes() calls this */
1447                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1448                         return (0);
1449                         }
1450
1451                 s->session->cipher=s->s3->tmp.new_cipher;
1452                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1453                 }
1454
1455         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1456                 return(0);
1457
1458         /* we have to record the message digest at
1459          * this point so we can get it before we read
1460          * the finished message */
1461         if (s->state & SSL_ST_CONNECT)
1462                 {
1463                 sender=s->method->ssl3_enc->server_finished_label;
1464                 slen=s->method->ssl3_enc->server_finished_label_len;
1465                 }
1466         else
1467                 {
1468                 sender=s->method->ssl3_enc->client_finished_label;
1469                 slen=s->method->ssl3_enc->client_finished_label_len;
1470                 }
1471
1472         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1473                 sender,slen,s->s3->tmp.peer_finish_md);
1474
1475         return(1);
1476         }
1477
1478 int ssl3_send_alert(SSL *s, int level, int desc)
1479         {
1480         /* Map tls/ssl alert value to correct one */
1481         desc=s->method->ssl3_enc->alert_value(desc);
1482         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1483                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1484         if (desc < 0) return -1;
1485         /* If a fatal one, remove from cache */
1486         if ((level == 2) && (s->session != NULL))
1487                 SSL_CTX_remove_session(s->ctx,s->session);
1488
1489         s->s3->alert_dispatch=1;
1490         s->s3->send_alert[0]=level;
1491         s->s3->send_alert[1]=desc;
1492         if (s->s3->wbuf.left == 0) /* data still being written out? */
1493                 return s->method->ssl_dispatch_alert(s);
1494         /* else data is still being written out, we will get written
1495          * some time in the future */
1496         return -1;
1497         }
1498
1499 int ssl3_dispatch_alert(SSL *s)
1500         {
1501         int i,j;
1502         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1503
1504         s->s3->alert_dispatch=0;
1505         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1506         if (i <= 0)
1507                 {
1508                 s->s3->alert_dispatch=1;
1509                 }
1510         else
1511                 {
1512                 /* Alert sent to BIO.  If it is important, flush it now.
1513                  * If the message does not get sent due to non-blocking IO,
1514                  * we will not worry too much. */
1515                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1516                         (void)BIO_flush(s->wbio);
1517
1518                 if (s->msg_callback)
1519                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1520
1521                 if (s->info_callback != NULL)
1522                         cb=s->info_callback;
1523                 else if (s->ctx->info_callback != NULL)
1524                         cb=s->ctx->info_callback;
1525
1526                 if (cb != NULL)
1527                         {
1528                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1529                         cb(s,SSL_CB_WRITE_ALERT,j);
1530                         }
1531                 }
1532         return(i);
1533         }