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) 1998-2001 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 <openssl/evp.h>
 116 #include <openssl/buffer.h>
 117 #include "ssl_locl.h"
 118
 119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 120                          unsigned int len);
 121 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 122                               unsigned int len);
 123 static int ssl3_get_record(SSL *s);
 124 static int do_compress(SSL *ssl);
 125 static int do_uncompress(SSL *ssl);
 126 static int do_change_cipher_spec(SSL *ssl);
 127
 128 /* used only by ssl3_get_record */
 129 static int ssl3_read_n(SSL *s, int n, int max, int extend)
 130         {
 131         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
 132          * packet by another n bytes.
 133          * The packet will be in the sub-array of s->s3->rbuf.buf specified
 134          * by s->packet and s->packet_length.
 135          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
 136          * [plus s->packet_length bytes if extend == 1].)
 137          */
 138         int i,off,newb;
 139
 140         if (!extend)
 141                 {
 142                 /* start with empty packet ... */
 143                 if (s->s3->rbuf.left == 0)
 144                         s->s3->rbuf.offset = 0;
 145                 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
 146                 s->packet_length = 0;
 147                 /* ... now we can act as if 'extend' was set */
 148                 }
 149
 150         /* if there is enough in the buffer from a previous read, take some */
 151         if (s->s3->rbuf.left >= (int)n)
 152                 {
 153                 s->packet_length+=n;
 154                 s->s3->rbuf.left-=n;
 155                 s->s3->rbuf.offset+=n;
 156                 return(n);
 157                 }
 158
 159         /* else we need to read more data */
 160         if (!s->read_ahead)
 161                 max=n;
 162
 163         {
 164                 /* avoid buffer overflow */
 165                 int max_max = SSL3_RT_MAX_PACKET_SIZE - s->packet_length;
 166                 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 167                         max_max += SSL3_RT_MAX_EXTRA;
 168                 if (max > max_max)
 169                         max = max_max;
 170         }
 171         if (n > max) /* does not happen */
 172                 {
 173                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 174                 return -1;
 175                 }
 176
 177         off = s->packet_length;
 178         newb = s->s3->rbuf.left;
 179         /* Move any available bytes to front of buffer:
 180          * 'off' bytes already pointed to by 'packet',
 181          * 'newb' extra ones at the end */
 182         if (s->packet != s->s3->rbuf.buf)
 183                 {
 184                 /*  off > 0 */
 185                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
 186                 s->packet = s->s3->rbuf.buf;
 187                 }
 188
 189         while (newb < n)
 190                 {
 191                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
 192                  * to read in more until we have off+n (up to off+max if possible) */
 193
 194                 clear_sys_error();
 195                 if (s->rbio != NULL)
 196                         {
 197                         s->rwstate=SSL_READING;
 198                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
 199                         }
 200                 else
 201                         {
 202                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 203                         i = -1;
 204                         }
 205
 206                 if (i <= 0)
 207                         {
 208                         s->s3->rbuf.left = newb;
 209                         return(i);
 210                         }
 211                 newb+=i;
 212                 }
 213
 214         /* done reading, now the book-keeping */
 215         s->s3->rbuf.offset = off + n;
 216         s->s3->rbuf.left = newb - n;
 217         s->packet_length += n;
 218         s->rwstate=SSL_NOTHING;
 219         return(n);
 220         }
 221
 222 /* Call this to get a new input record.
 223  * It will return <= 0 if more data is needed, normally due to an error
 224  * or non-blocking IO.
 225  * When it finishes, one packet has been decoded and can be found in
 226  * ssl->s3->rrec.type    - is the type of record
 227  * ssl->s3->rrec.data,   - data
 228  * ssl->s3->rrec.length, - number of bytes
 229  */
 230 /* used only by ssl3_read_bytes */
 231 static int ssl3_get_record(SSL *s)
 232         {
 233         int ssl_major,ssl_minor,al;
 234         int enc_err,n,i,ret= -1;
 235         SSL3_RECORD *rr;
 236         SSL_SESSION *sess;
 237         unsigned char *p;
 238         unsigned char md[EVP_MAX_MD_SIZE];
 239         short version;
 240         unsigned int mac_size;
 241         int clear=0,extra;
 242
 243         rr= &(s->s3->rrec);
 244         sess=s->session;
 245
 246         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 247                 extra=SSL3_RT_MAX_EXTRA;
 248         else
 249                 extra=0;
 250
 251 again:
 252         /* check if we have the header */
 253         if (    (s->rstate != SSL_ST_READ_BODY) ||
 254                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 255                 {
 256                 n=ssl3_read_n(s,SSL3_RT_HEADER_LENGTH,
 257                         SSL3_RT_MAX_PACKET_SIZE,0);
 258                 if (n <= 0) return(n); /* error or non-blocking */
 259                 s->rstate=SSL_ST_READ_BODY;
 260
 261                 p=s->packet;
 262
 263                 /* Pull apart the header into the SSL3_RECORD */
 264                 rr->type= *(p++);
 265                 ssl_major= *(p++);
 266                 ssl_minor= *(p++);
 267                 version=(ssl_major<<8)|ssl_minor;
 268                 n2s(p,rr->length);
 269
 270                 /* Lets check version */
 271                 if (s->first_packet)
 272                         {
 273                         s->first_packet=0;
 274                         }
 275                 else
 276                         {
 277                         if (version != s->version)
 278                                 {
 279                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 280                                 /* Send back error using their
 281                                  * version number :-) */
 282                                 s->version=version;
 283                                 al=SSL_AD_PROTOCOL_VERSION;
 284                                 goto f_err;
 285                                 }
 286                         }
 287
 288                 if ((version>>8) != SSL3_VERSION_MAJOR)
 289                         {
 290                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 291                         goto err;
 292                         }
 293
 294                 if (rr->length >
 295                         (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 296                         {
 297                         al=SSL_AD_RECORD_OVERFLOW;
 298                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 299                         goto f_err;
 300                         }
 301
 302                 /* now s->rstate == SSL_ST_READ_BODY */
 303                 }
 304
 305         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 306
 307         if (rr->length > (s->packet_length-SSL3_RT_HEADER_LENGTH))
 308                 {
 309                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
 310                 i=rr->length;
 311                 n=ssl3_read_n(s,i,i,1);
 312                 if (n <= 0) return(n); /* error or non-blocking io */
 313                 /* now n == rr->length,
 314                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
 315                 }
 316
 317         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 318
 319         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 320          * and we have that many bytes in s->packet
 321          */
 322         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 323
 324         /* ok, we can now read from 's->packet' data into 'rr'
 325          * rr->input points at rr->length bytes, which
 326          * need to be copied into rr->data by either
 327          * the decryption or by the decompression
 328          * When the data is 'copied' into the rr->data buffer,
 329          * rr->input will be pointed at the new buffer */
 330
 331         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 332          * rr->length bytes of encrypted compressed stuff. */
 333
 334         /* check is not needed I believe */
 335         if (rr->length > (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 336                 {
 337                 al=SSL_AD_RECORD_OVERFLOW;
 338                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 339                 goto f_err;
 340                 }
 341
 342         /* decrypt in place in 'rr->input' */
 343         rr->data=rr->input;
 344
 345         enc_err = s->method->ssl3_enc->enc(s,0);
 346         if (enc_err <= 0)
 347                 {
 348                 if (enc_err == 0)
 349                         /* SSLerr() and ssl3_send_alert() have been called */
 350                         goto err;
 351
 352                 /* otherwise enc_err == -1 */
 353                 goto decryption_failed_or_bad_record_mac;
 354                 }
 355
 356 #ifdef TLS_DEBUG
 357 printf("dec %d\n",rr->length);
 358 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 359 printf("\n");
 360 #endif
 361
 362         /* r->length is now the compressed data plus mac */
 363         if (    (sess == NULL) ||
 364                 (s->enc_read_ctx == NULL) ||
 365                 (s->read_hash == NULL))
 366                 clear=1;
 367
 368         if (!clear)
 369                 {
 370                 mac_size=EVP_MD_size(s->read_hash);
 371
 372                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 373                         {
 374 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
 375                         al=SSL_AD_RECORD_OVERFLOW;
 376                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
 377                         goto f_err;
 378 #else
 379                         goto decryption_failed_or_bad_record_mac;
 380 #endif
 381                         }
 382                 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
 383                 if (rr->length < mac_size)
 384                         {
 385 #if 0 /* OK only for stream ciphers */
 386                         al=SSL_AD_DECODE_ERROR;
 387                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 388                         goto f_err;
 389 #else
 390                         goto decryption_failed_or_bad_record_mac;
 391 #endif
 392                         }
 393                 rr->length-=mac_size;
 394                 i=s->method->ssl3_enc->mac(s,md,0);
 395                 if (memcmp(md,&(rr->data[rr->length]),mac_size) != 0)
 396                         {
 397                         goto decryption_failed_or_bad_record_mac;
 398                         }
 399                 }
 400
 401         /* r->length is now just compressed */
 402         if (s->expand != NULL)
 403                 {
 404                 if (rr->length >
 405                         (unsigned int)SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 406                         {
 407                         al=SSL_AD_RECORD_OVERFLOW;
 408                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 409                         goto f_err;
 410                         }
 411                 if (!do_uncompress(s))
 412                         {
 413                         al=SSL_AD_DECOMPRESSION_FAILURE;
 414                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 415                         goto f_err;
 416                         }
 417                 }
 418
 419         if (rr->length > (unsigned int)SSL3_RT_MAX_PLAIN_LENGTH+extra)
 420                 {
 421                 al=SSL_AD_RECORD_OVERFLOW;
 422                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 423                 goto f_err;
 424                 }
 425
 426         rr->off=0;
 427         /* So at this point the following is true
 428          * ssl->s3->rrec.type   is the type of record
 429          * ssl->s3->rrec.length == number of bytes in record
 430          * ssl->s3->rrec.off    == offset to first valid byte
 431          * ssl->s3->rrec.data   == where to take bytes from, increment
 432          *                         after use :-).
 433          */
 434
 435         /* we have pulled in a full packet so zero things */
 436         s->packet_length=0;
 437
 438         /* just read a 0 length packet */
 439         if (rr->length == 0) goto again;
 440
 441         return(1);
 442
 443 decryption_failed_or_bad_record_mac:
 444         /* Separate 'decryption_failed' alert was introduced with TLS 1.0,
 445          * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
 446          * failure is directly visible from the ciphertext anyway,
 447          * we should not reveal which kind of error occured -- this
 448          * might become visible to an attacker (e.g. via logfile) */
 449         al=SSL_AD_BAD_RECORD_MAC;
 450         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
 451 f_err:
 452         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 453 err:
 454         return(ret);
 455         }
 456
 457 static int do_uncompress(SSL *ssl)
 458         {
 459         int i;
 460         SSL3_RECORD *rr;
 461
 462         rr= &(ssl->s3->rrec);
 463         i=COMP_expand_block(ssl->expand,rr->comp,
 464                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 465         if (i < 0)
 466                 return(0);
 467         else
 468                 rr->length=i;
 469         rr->data=rr->comp;
 470
 471         return(1);
 472         }
 473
 474 static int do_compress(SSL *ssl)
 475         {
 476         int i;
 477         SSL3_RECORD *wr;
 478
 479         wr= &(ssl->s3->wrec);
 480         i=COMP_compress_block(ssl->compress,wr->data,
 481                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 482                 wr->input,(int)wr->length);
 483         if (i < 0)
 484                 return(0);
 485         else
 486                 wr->length=i;
 487
 488         wr->input=wr->data;
 489         return(1);
 490         }
 491
 492 /* Call this to write data in records of type 'type'
 493  * It will return <= 0 if not all data has been sent or non-blocking IO.
 494  */
 495 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 496         {
 497         const unsigned char *buf=buf_;
 498         unsigned int tot,n,nw;
 499         int i;
 500
 501         s->rwstate=SSL_NOTHING;
 502         tot=s->s3->wnum;
 503         s->s3->wnum=0;
 504
 505         if (SSL_in_init(s) && !s->in_handshake)
 506                 {
 507                 i=s->handshake_func(s);
 508                 if (i < 0) return(i);
 509                 if (i == 0)
 510                         {
 511                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 512                         return(-1);
 513                         }
 514                 }
 515
 516         n=(len-tot);
 517         for (;;)
 518                 {
 519                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
 520                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
 521                 else
 522                         nw=n;
 523
 524                 i=do_ssl3_write(s,type,&(buf[tot]),nw);
 525                 if (i <= 0)
 526                         {
 527                         s->s3->wnum=tot;
 528                         return(i);
 529                         }
 530
 531                 if ((i == (int)n) ||
 532                         (type == SSL3_RT_APPLICATION_DATA &&
 533                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
 534                         {
 535                         return(tot+i);
 536                         }
 537
 538                 n-=i;
 539                 tot+=i;
 540                 }
 541         }
 542
 543 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 544                          unsigned int len)
 545         {
 546         unsigned char *p,*plen;
 547         int i,mac_size,clear=0;
 548         SSL3_RECORD *wr;
 549         SSL3_BUFFER *wb;
 550         SSL_SESSION *sess;
 551
 552         /* first check is there is a SSL3_RECORD still being written
 553          * out.  This will happen with non blocking IO */
 554         if (s->s3->wbuf.left != 0)
 555                 return(ssl3_write_pending(s,type,buf,len));
 556
 557         /* If we have an alert to send, lets send it */
 558         if (s->s3->alert_dispatch)
 559                 {
 560                 i=ssl3_dispatch_alert(s);
 561                 if (i <= 0)
 562                         return(i);
 563                 /* if it went, fall through and send more stuff */
 564                 }
 565
 566         if (len == 0) return(len);
 567
 568         wr= &(s->s3->wrec);
 569         wb= &(s->s3->wbuf);
 570         sess=s->session;
 571
 572         if (    (sess == NULL) ||
 573                 (s->enc_write_ctx == NULL) ||
 574                 (s->write_hash == NULL))
 575                 clear=1;
 576
 577         if (clear)
 578                 mac_size=0;
 579         else
 580                 mac_size=EVP_MD_size(s->write_hash);
 581
 582         p=wb->buf;
 583
 584         /* write the header */
 585         *(p++)=type&0xff;
 586         wr->type=type;
 587
 588         *(p++)=(s->version>>8);
 589         *(p++)=s->version&0xff;
 590
 591         /* record where we are to write out packet length */
 592         plen=p;
 593         p+=2;
 594
 595         /* lets setup the record stuff. */
 596         wr->data=p;
 597         wr->length=(int)len;
 598         wr->input=(unsigned char *)buf;
 599
 600         /* we now 'read' from wr->input, wr->length bytes into
 601          * wr->data */
 602
 603         /* first we compress */
 604         if (s->compress != NULL)
 605                 {
 606                 if (!do_compress(s))
 607                         {
 608                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 609                         goto err;
 610                         }
 611                 }
 612         else
 613                 {
 614                 memcpy(wr->data,wr->input,wr->length);
 615                 wr->input=wr->data;
 616                 }
 617
 618         /* we should still have the output to wr->data and the input
 619          * from wr->input.  Length should be wr->length.
 620          * wr->data still points in the wb->buf */
 621
 622         if (mac_size != 0)
 623                 {
 624                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
 625                 wr->length+=mac_size;
 626                 wr->input=p;
 627                 wr->data=p;
 628                 }
 629
 630         /* ssl3_enc can only have an error on read */
 631         s->method->ssl3_enc->enc(s,1);
 632
 633         /* record length after mac and block padding */
 634         s2n(wr->length,plen);
 635
 636         /* we should now have
 637          * wr->data pointing to the encrypted data, which is
 638          * wr->length long */
 639         wr->type=type; /* not needed but helps for debugging */
 640         wr->length+=SSL3_RT_HEADER_LENGTH;
 641
 642         /* Now lets setup wb */
 643         wb->left=wr->length;
 644         wb->offset=0;
 645
 646         s->s3->wpend_tot=len;
 647         s->s3->wpend_buf=buf;
 648         s->s3->wpend_type=type;
 649         s->s3->wpend_ret=len;
 650
 651         /* we now just need to write the buffer */
 652         return(ssl3_write_pending(s,type,buf,len));
 653 err:
 654         return(-1);
 655         }
 656
 657 /* if s->s3->wbuf.left != 0, we need to call this */
 658 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 659                               unsigned int len)
 660         {
 661         int i;
 662
 663 /* XXXX */
 664         if ((s->s3->wpend_tot > (int)len)
 665                 || ((s->s3->wpend_buf != buf) &&
 666                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 667                 || (s->s3->wpend_type != type))
 668                 {
 669                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 670                 return(-1);
 671                 }
 672
 673         for (;;)
 674                 {
 675                 clear_sys_error();
 676                 if (s->wbio != NULL)
 677                         {
 678                         s->rwstate=SSL_WRITING;
 679                         i=BIO_write(s->wbio,
 680                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
 681                                 (unsigned int)s->s3->wbuf.left);
 682                         }
 683                 else
 684                         {
 685                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 686                         i= -1;
 687                         }
 688                 if (i == s->s3->wbuf.left)
 689                         {
 690                         s->s3->wbuf.left=0;
 691                         s->rwstate=SSL_NOTHING;
 692                         return(s->s3->wpend_ret);
 693                         }
 694                 else if (i <= 0)
 695                         return(i);
 696                 s->s3->wbuf.offset+=i;
 697                 s->s3->wbuf.left-=i;
 698                 }
 699         }
 700
 701 /* Return up to 'len' payload bytes received in 'type' records.
 702  * 'type' is one of the following:
 703  *
 704  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 705  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 706  *   -  0 (during a shutdown, no data has to be returned)
 707  *
 708  * If we don't have stored data to work from, read a SSL/TLS record first
 709  * (possibly multiple records if we still don't have anything to return).
 710  *
 711  * This function must handle any surprises the peer may have for us, such as
 712  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 713  * a surprise, but handled as if it were), or renegotiation requests.
 714  * Also if record payloads contain fragments too small to process, we store
 715  * them until there is enough for the respective protocol (the record protocol
 716  * may use arbitrary fragmentation and even interleaving):
 717  *     Change cipher spec protocol
 718  *             just 1 byte needed, no need for keeping anything stored
 719  *     Alert protocol
 720  *             2 bytes needed (AlertLevel, AlertDescription)
 721  *     Handshake protocol
 722  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 723  *             to detect unexpected Client Hello and Hello Request messages
 724  *             here, anything else is handled by higher layers
 725  *     Application data protocol
 726  *             none of our business
 727  */
 728 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 729         {
 730         int al,i,j,ret;
 731         unsigned int n;
 732         SSL3_RECORD *rr;
 733         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 734
 735         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 736                 if (!ssl3_setup_buffers(s))
 737                         return(-1);
 738
 739         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
 740             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 741                 {
 742                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
 743                 return -1;
 744                 }
 745
 746         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
 747                 /* (partially) satisfy request from storage */
 748                 {
 749                 unsigned char *src = s->s3->handshake_fragment;
 750                 unsigned char *dst = buf;
 751                 unsigned int k;
 752
 753                 /* peek == 0 */
 754                 n = 0;
 755                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
 756                         {
 757                         *dst++ = *src++;
 758                         len--; s->s3->handshake_fragment_len--;
 759                         n++;
 760                         }
 761                 /* move any remaining fragment bytes: */
 762                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
 763                         s->s3->handshake_fragment[k] = *src++;
 764                 return n;
 765         }
 766
 767         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 768
 769         if (!s->in_handshake && SSL_in_init(s))
 770                 {
 771                 /* type == SSL3_RT_APPLICATION_DATA */
 772                 i=s->handshake_func(s);
 773                 if (i < 0) return(i);
 774                 if (i == 0)
 775                         {
 776                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 777                         return(-1);
 778                         }
 779                 }
 780 start:
 781         s->rwstate=SSL_NOTHING;
 782
 783         /* s->s3->rrec.type         - is the type of record
 784          * s->s3->rrec.data,    - data
 785          * s->s3->rrec.off,     - offset into 'data' for next read
 786          * s->s3->rrec.length,  - number of bytes. */
 787         rr = &(s->s3->rrec);
 788
 789         /* get new packet if necessary */
 790         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 791                 {
 792                 ret=ssl3_get_record(s);
 793                 if (ret <= 0) return(ret);
 794                 }
 795
 796         /* we now have a packet which can be read and processed */
 797
 798         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 799                                        * reset by ssl3_get_finished */
 800                 && (rr->type != SSL3_RT_HANDSHAKE))
 801                 {
 802                 al=SSL_AD_UNEXPECTED_MESSAGE;
 803                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 804                 goto err;
 805                 }
 806
 807         /* If the other end has shut down, throw anything we read away
 808          * (even in 'peek' mode) */
 809         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 810                 {
 811                 rr->length=0;
 812                 s->rwstate=SSL_NOTHING;
 813                 return(0);
 814                 }
 815
 816
 817         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 818                 {
 819                 /* make sure that we are not getting application data when we
 820                  * are doing a handshake for the first time */
 821                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 822                         (s->enc_read_ctx == NULL))
 823                         {
 824                         al=SSL_AD_UNEXPECTED_MESSAGE;
 825                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 826                         goto f_err;
 827                         }
 828
 829                 if (len <= 0) return(len);
 830
 831                 if ((unsigned int)len > rr->length)
 832                         n = rr->length;
 833                 else
 834                         n = (unsigned int)len;
 835
 836                 memcpy(buf,&(rr->data[rr->off]),n);
 837                 if (!peek)
 838                         {
 839                         rr->length-=n;
 840                         rr->off+=n;
 841                         if (rr->length == 0)
 842                                 {
 843                                 s->rstate=SSL_ST_READ_HEADER;
 844                                 rr->off=0;
 845                                 }
 846                         }
 847                 return(n);
 848                 }
 849
 850
 851         /* If we get here, then type != rr->type; if we have a handshake
 852          * message, then it was unexpected (Hello Request or Client Hello). */
 853
 854         /* In case of record types for which we have 'fragment' storage,
 855          * fill that so that we can process the data at a fixed place.
 856          */
 857                 {
 858                 unsigned int dest_maxlen = 0;
 859                 unsigned char *dest = NULL;
 860                 unsigned int *dest_len = NULL;
 861
 862                 if (rr->type == SSL3_RT_HANDSHAKE)
 863                         {
 864                         dest_maxlen = sizeof s->s3->handshake_fragment;
 865                         dest = s->s3->handshake_fragment;
 866                         dest_len = &s->s3->handshake_fragment_len;
 867                         }
 868                 else if (rr->type == SSL3_RT_ALERT)
 869                         {
 870                         dest_maxlen = sizeof s->s3->alert_fragment;
 871                         dest = s->s3->alert_fragment;
 872                         dest_len = &s->s3->alert_fragment_len;
 873                         }
 874
 875                 if (dest_maxlen > 0)
 876                         {
 877                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
 878                         if (rr->length < n)
 879                                 n = rr->length; /* available bytes */
 880
 881                         /* now move 'n' bytes: */
 882                         while (n-- > 0)
 883                                 {
 884                                 dest[(*dest_len)++] = rr->data[rr->off++];
 885                                 rr->length--;
 886                                 }
 887
 888                         if (*dest_len < dest_maxlen)
 889                                 goto start; /* fragment was too small */
 890                         }
 891                 }
 892
 893         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
 894          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
 895          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
 896
 897         /* If we are a client, check for an incoming 'Hello Request': */
 898         if ((!s->server) &&
 899                 (s->s3->handshake_fragment_len >= 4) &&
 900                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
 901                 (s->session != NULL) && (s->session->cipher != NULL))
 902                 {
 903                 s->s3->handshake_fragment_len = 0;
 904
 905                 if ((s->s3->handshake_fragment[1] != 0) ||
 906                         (s->s3->handshake_fragment[2] != 0) ||
 907                         (s->s3->handshake_fragment[3] != 0))
 908                         {
 909                         al=SSL_AD_DECODE_ERROR;
 910                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
 911                         goto err;
 912                         }
 913
 914                 if (s->msg_callback)
 915                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
 916
 917                 if (SSL_is_init_finished(s) &&
 918                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
 919                         !s->s3->renegotiate)
 920                         {
 921                         ssl3_renegotiate(s);
 922                         if (ssl3_renegotiate_check(s))
 923                                 {
 924                                 i=s->handshake_func(s);
 925                                 if (i < 0) return(i);
 926                                 if (i == 0)
 927                                         {
 928                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 929                                         return(-1);
 930                                         }
 931
 932                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
 933                                         {
 934                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
 935                                                 {
 936                                                 BIO *bio;
 937                                                 /* In the case where we try to read application data,
 938                                                  * but we trigger an SSL handshake, we return -1 with
 939                                                  * the retry option set.  Otherwise renegotiation may
 940                                                  * cause nasty problems in the blocking world */
 941                                                 s->rwstate=SSL_READING;
 942                                                 bio=SSL_get_rbio(s);
 943                                                 BIO_clear_retry_flags(bio);
 944                                                 BIO_set_retry_read(bio);
 945                                                 return(-1);
 946                                                 }
 947                                         }
 948                                 }
 949                         }
 950                 /* we either finished a handshake or ignored the request,
 951                  * now try again to obtain the (application) data we were asked for */
 952                 goto start;
 953                 }
 954
 955         if (s->s3->alert_fragment_len >= 2)
 956                 {
 957                 int alert_level = s->s3->alert_fragment[0];
 958                 int alert_descr = s->s3->alert_fragment[1];
 959
 960                 s->s3->alert_fragment_len = 0;
 961
 962                 if (s->msg_callback)
 963                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
 964
 965                 if (s->info_callback != NULL)
 966                         cb=s->info_callback;
 967                 else if (s->ctx->info_callback != NULL)
 968                         cb=s->ctx->info_callback;
 969
 970                 if (cb != NULL)
 971                         {
 972                         j = (alert_level << 8) | alert_descr;
 973                         cb(s, SSL_CB_READ_ALERT, j);
 974                         }
 975
 976                 if (alert_level == 1) /* warning */
 977                         {
 978                         s->s3->warn_alert = alert_descr;
 979                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
 980                                 {
 981                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
 982                                 return(0);
 983                                 }
 984                         }
 985                 else if (alert_level == 2) /* fatal */
 986                         {
 987                         char tmp[16];
 988
 989                         s->rwstate=SSL_NOTHING;
 990                         s->s3->fatal_alert = alert_descr;
 991                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
 992                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
 993                         ERR_add_error_data(2,"SSL alert number ",tmp);
 994                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
 995                         SSL_CTX_remove_session(s->ctx,s->session);
 996                         return(0);
 997                         }
 998                 else
 999                         {
1000                         al=SSL_AD_ILLEGAL_PARAMETER;
1001                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1002                         goto f_err;
1003                         }
1004
1005                 goto start;
1006                 }
1007
1008         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1009                 {
1010                 s->rwstate=SSL_NOTHING;
1011                 rr->length=0;
1012                 return(0);
1013                 }
1014
1015         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1016                 {
1017                 /* 'Change Cipher Spec' is just a single byte, so we know
1018                  * exactly what the record payload has to look like */
1019                 if (    (rr->length != 1) || (rr->off != 0) ||
1020                         (rr->data[0] != SSL3_MT_CCS))
1021                         {
1022                         i=SSL_AD_ILLEGAL_PARAMETER;
1023                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1024                         goto err;
1025                         }
1026
1027                 rr->length=0;
1028
1029                 if (s->msg_callback)
1030                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1031
1032                 s->s3->change_cipher_spec=1;
1033                 if (!do_change_cipher_spec(s))
1034                         goto err;
1035                 else
1036                         goto start;
1037                 }
1038
1039         /* Unexpected handshake message (Client Hello, or protocol violation) */
1040         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1041                 {
1042                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1043                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1044                         {
1045 #if 0 /* worked only because C operator preferences are not as expected (and
1046        * because this is not really needed for clients except for detecting
1047        * protocol violations): */
1048                         s->state=SSL_ST_BEFORE|(s->server)
1049                                 ?SSL_ST_ACCEPT
1050                                 :SSL_ST_CONNECT;
1051 #else
1052                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1053 #endif
1054                         s->new_session=1;
1055                         }
1056                 i=s->handshake_func(s);
1057                 if (i < 0) return(i);
1058                 if (i == 0)
1059                         {
1060                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1061                         return(-1);
1062                         }
1063
1064                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1065                         {
1066                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1067                                 {
1068                                 BIO *bio;
1069                                 /* In the case where we try to read application data,
1070                                  * but we trigger an SSL handshake, we return -1 with
1071                                  * the retry option set.  Otherwise renegotiation may
1072                                  * cause nasty problems in the blocking world */
1073                                 s->rwstate=SSL_READING;
1074                                 bio=SSL_get_rbio(s);
1075                                 BIO_clear_retry_flags(bio);
1076                                 BIO_set_retry_read(bio);
1077                                 return(-1);
1078                                 }
1079                         }
1080                 goto start;
1081                 }
1082
1083         switch (rr->type)
1084                 {
1085         default:
1086 #ifndef OPENSSL_NO_TLS
1087                 /* TLS just ignores unknown message types */
1088                 if (s->version == TLS1_VERSION)
1089                         {
1090                         rr->length = 0;
1091                         goto start;
1092                         }
1093 #endif
1094                 al=SSL_AD_UNEXPECTED_MESSAGE;
1095                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1096                 goto f_err;
1097         case SSL3_RT_CHANGE_CIPHER_SPEC:
1098         case SSL3_RT_ALERT:
1099         case SSL3_RT_HANDSHAKE:
1100                 /* we already handled all of these, with the possible exception
1101                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1102                  * should not happen when type != rr->type */
1103                 al=SSL_AD_UNEXPECTED_MESSAGE;
1104                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1105                 goto f_err;
1106         case SSL3_RT_APPLICATION_DATA:
1107                 /* At this point, we were expecting handshake data,
1108                  * but have application data.  If the library was
1109                  * running inside ssl3_read() (i.e. in_read_app_data
1110                  * is set) and it makes sense to read application data
1111                  * at this point (session renegotiation not yet started),
1112                  * we will indulge it.
1113                  */
1114                 if (s->s3->in_read_app_data &&
1115                         (s->s3->total_renegotiations != 0) &&
1116                         ((
1117                                 (s->state & SSL_ST_CONNECT) &&
1118                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1119                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1120                                 ) || (
1121                                         (s->state & SSL_ST_ACCEPT) &&
1122                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1123                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1124                                         )
1125                                 ))
1126                         {
1127                         s->s3->in_read_app_data=0;
1128                         return(-1);
1129                         }
1130                 else
1131                         {
1132                         al=SSL_AD_UNEXPECTED_MESSAGE;
1133                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1134                         goto f_err;
1135                         }
1136                 }
1137         /* not reached */
1138
1139 f_err:
1140         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1141 err:
1142         return(-1);
1143         }
1144
1145 static int do_change_cipher_spec(SSL *s)
1146         {
1147         int i;
1148         const char *sender;
1149         int slen;
1150
1151         if (s->state & SSL_ST_ACCEPT)
1152                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1153         else
1154                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1155
1156         if (s->s3->tmp.key_block == NULL)
1157                 {
1158                 s->session->cipher=s->s3->tmp.new_cipher;
1159                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1160                 }
1161
1162         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1163                 return(0);
1164
1165         /* we have to record the message digest at
1166          * this point so we can get it before we read
1167          * the finished message */
1168         if (s->state & SSL_ST_CONNECT)
1169                 {
1170                 sender=s->method->ssl3_enc->server_finished_label;
1171                 slen=s->method->ssl3_enc->server_finished_label_len;
1172                 }
1173         else
1174                 {
1175                 sender=s->method->ssl3_enc->client_finished_label;
1176                 slen=s->method->ssl3_enc->client_finished_label_len;
1177                 }
1178
1179         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1180                 &(s->s3->finish_dgst1),
1181                 &(s->s3->finish_dgst2),
1182                 sender,slen,s->s3->tmp.peer_finish_md);
1183
1184         return(1);
1185         }
1186
1187 void ssl3_send_alert(SSL *s, int level, int desc)
1188         {
1189         /* Map tls/ssl alert value to correct one */
1190         desc=s->method->ssl3_enc->alert_value(desc);
1191         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1192                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1193         if (desc < 0) return;
1194         /* If a fatal one, remove from cache */
1195         if ((level == 2) && (s->session != NULL))
1196                 SSL_CTX_remove_session(s->ctx,s->session);
1197
1198         s->s3->alert_dispatch=1;
1199         s->s3->send_alert[0]=level;
1200         s->s3->send_alert[1]=desc;
1201         if (s->s3->wbuf.left == 0) /* data still being written out? */
1202                 ssl3_dispatch_alert(s);
1203         /* else data is still being written out, we will get written
1204          * some time in the future */
1205         }
1206
1207 int ssl3_dispatch_alert(SSL *s)
1208         {
1209         int i,j;
1210         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1211
1212         s->s3->alert_dispatch=0;
1213         i=do_ssl3_write(s,SSL3_RT_ALERT,&s->s3->send_alert[0],2);
1214         if (i <= 0)
1215                 {
1216                 s->s3->alert_dispatch=1;
1217                 }
1218         else
1219                 {
1220                 /* Alert sent to BIO.  If it is important, flush it now.
1221                  * If the message does not get sent due to non-blocking IO,
1222                  * we will not worry too much. */
1223                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1224                         (void)BIO_flush(s->wbio);
1225
1226                 if (s->msg_callback)
1227                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1228
1229                 if (s->info_callback != NULL)
1230                         cb=s->info_callback;
1231                 else if (s->ctx->info_callback != NULL)
1232                         cb=s->ctx->info_callback;
1233
1234                 if (cb != NULL)
1235                         {
1236                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1237                         cb(s,SSL_CB_WRITE_ALERT,j);
1238                         }
1239                 }
1240         return(i);
1241         }