ssl/s3_pkt.c

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