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 #include <stdio.h>
  60 #include <errno.h>
  61 #define USE_SOCKETS
  62 #include <openssl/evp.h>
  63 #include <openssl/buffer.h>
  64 #include "ssl_locl.h"
  65
  66 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
  67                          unsigned int len);
  68 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
  69                               unsigned int len);
  70 static int ssl3_get_record(SSL *s);
  71 static int do_compress(SSL *ssl);
  72 static int do_uncompress(SSL *ssl);
  73 static int do_change_cipher_spec(SSL *ssl);
  74 static int ssl3_read_n(SSL *s, int n, int max, int extend)
  75         {
  76         int i,off,newb;
  77
  78         /* if there is stuff still in the buffer from a previous read,
  79          * and there is more than we want, take some. */
  80         if (s->s3->rbuf.left >= (int)n)
  81                 {
  82                 if (extend)
  83                         s->packet_length+=n;
  84                 else
  85                         {
  86                         s->packet= &(s->s3->rbuf.buf[s->s3->rbuf.offset]);
  87                         s->packet_length=n;
  88                         }
  89                 s->s3->rbuf.left-=n;
  90                 s->s3->rbuf.offset+=n;
  91                 return(n);
  92                 }
  93
  94         /* else we need to read more data */
  95         if (!s->read_ahead) max=n;
  96         if (max > SSL3_RT_MAX_PACKET_SIZE)
  97                 max=SSL3_RT_MAX_PACKET_SIZE;
  98
  99         /* First check if there is some left or we want to extend */
 100         off=0;
 101         if (    (s->s3->rbuf.left != 0) ||
 102                 ((s->packet_length != 0) && extend))
 103                 {
 104                 newb=s->s3->rbuf.left;
 105                 if (extend)
 106                         {
 107                         /* Copy bytes back to the front of the buffer
 108                          * Take the bytes already pointed to by 'packet'
 109                          * and take the extra ones on the end. */
 110                         off=s->packet_length;
 111                         if (s->packet != s->s3->rbuf.buf)
 112                                 memcpy(s->s3->rbuf.buf,s->packet,newb+off);
 113                         }
 114                 else if (s->s3->rbuf.offset != 0)
 115                         { /* so the data is not at the start of the buffer */
 116                         memcpy(s->s3->rbuf.buf,
 117                                 &(s->s3->rbuf.buf[s->s3->rbuf.offset]),newb);
 118                         s->s3->rbuf.offset=0;
 119                         }
 120
 121                 s->s3->rbuf.left=0;
 122                 }
 123         else
 124                 newb=0;
 125
 126         /* So we now have 'newb' bytes at the front of
 127          * s->s3->rbuf.buf and need to read some more in on the end
 128          * We start reading into the buffer at 's->s3->rbuf.offset'
 129          */
 130         s->packet=s->s3->rbuf.buf;
 131
 132         while (newb < n)
 133                 {
 134                 clear_sys_error();
 135                 if (s->rbio != NULL)
 136                         {
 137                         s->rwstate=SSL_READING;
 138                         i=BIO_read(s->rbio,
 139                                 (char *)&(s->s3->rbuf.buf[off+newb]),
 140                                 max-newb);
 141                         }
 142                 else
 143                         {
 144                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
 145                         i= -1;
 146                         }
 147
 148                 if (i <= 0)
 149                         {
 150                         s->s3->rbuf.left+=newb;
 151                         return(i);
 152                         }
 153                 newb+=i;
 154                 }
 155
 156         /* record used data read */
 157         if (newb > n)
 158                 {
 159                 s->s3->rbuf.offset=n+off;
 160                 s->s3->rbuf.left=newb-n;
 161                 }
 162         else
 163                 {
 164                 s->s3->rbuf.offset=0;
 165                 s->s3->rbuf.left=0;
 166                 }
 167
 168         if (extend)
 169                 s->packet_length+=n;
 170         else
 171                 s->packet_length+=n;
 172         return(n);
 173         }
 174
 175 /* Call this to get a new input record.
 176  * It will return <= 0 if more data is needed, normally due to an error
 177  * or non-blocking IO.
 178  * When it finishes, one packet has been decoded and can be found in
 179  * ssl->s3->rrec.type   - is the type of record
 180  * ssl->s3->rrec.data,  - data
 181  * ssl->s3->rrec.length, - number of bytes
 182  */
 183 static int ssl3_get_record(SSL *s)
 184         {
 185         int ssl_major,ssl_minor,al;
 186         int n,i,ret= -1;
 187         SSL3_BUFFER *rb;
 188         SSL3_RECORD *rr;
 189         SSL_SESSION *sess;
 190         unsigned char *p;
 191         unsigned char md[EVP_MAX_MD_SIZE];
 192         short version;
 193         unsigned int mac_size;
 194         int clear=0,extra;
 195
 196         rr= &(s->s3->rrec);
 197         rb= &(s->s3->rbuf);
 198         sess=s->session;
 199
 200         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
 201                 extra=SSL3_RT_MAX_EXTRA;
 202         else
 203                 extra=0;
 204
 205 again:
 206         /* check if we have the header */
 207         if (    (s->rstate != SSL_ST_READ_BODY) ||
 208                 (s->packet_length < SSL3_RT_HEADER_LENGTH))
 209                 {
 210                 n=ssl3_read_n(s,SSL3_RT_HEADER_LENGTH,
 211                         SSL3_RT_MAX_PACKET_SIZE,0);
 212                 if (n <= 0) return(n); /* error or non-blocking */
 213                 s->rstate=SSL_ST_READ_BODY;
 214
 215                 p=s->packet;
 216
 217                 /* Pull apart the header into the SSL3_RECORD */
 218                 rr->type= *(p++);
 219                 ssl_major= *(p++);
 220                 ssl_minor= *(p++);
 221                 version=(ssl_major<<8)|ssl_minor;
 222                 n2s(p,rr->length);
 223
 224                 /* Lets check version */
 225                 if (s->first_packet)
 226                         {
 227                         s->first_packet=0;
 228                         }
 229                 else
 230                         {
 231                         if (version != s->version)
 232                                 {
 233                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 234                                 /* Send back error using their
 235                                  * version number :-) */
 236                                 s->version=version;
 237                                 al=SSL_AD_PROTOCOL_VERSION;
 238                                 goto f_err;
 239                                 }
 240                         }
 241
 242                 if ((version>>8) != SSL3_VERSION_MAJOR)
 243                         {
 244                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
 245                         goto err;
 246                         }
 247
 248                 if (rr->length >
 249                         (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 250                         {
 251                         al=SSL_AD_RECORD_OVERFLOW;
 252                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
 253                         goto f_err;
 254                         }
 255
 256                 s->rstate=SSL_ST_READ_BODY;
 257                 }
 258
 259         /* get and decode the data */
 260         if (s->rstate == SSL_ST_READ_BODY)
 261                 {
 262                 if (rr->length > (s->packet_length-SSL3_RT_HEADER_LENGTH))
 263                         {
 264                         i=rr->length;
 265                         /*-(s->packet_length-SSL3_RT_HEADER_LENGTH); */
 266                         n=ssl3_read_n(s,i,i,1);
 267                         if (n <= 0) return(n); /* error or non-blocking io */
 268                         }
 269                 s->rstate=SSL_ST_READ_HEADER;
 270                 }
 271
 272         /* At this point, we have the data in s->packet and there should be
 273          * s->packet_length bytes, we must not 'overrun' this buffer :-)
 274          * One of the following functions will copy the data from the
 275          * s->packet buffer */
 276
 277         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
 278
 279         /* ok, we can now read from 's->packet' data into 'rr'
 280          * rr->input points at rr->length bytes, which
 281          * need to be copied into rr->data by either
 282          * the decryption or by the decompression
 283          * When the data is 'copied' into the rr->data buffer,
 284          * rr->input will be pointed at the new buffer */
 285
 286         /* Set the state for the following operations */
 287         s->rstate=SSL_ST_READ_HEADER;
 288
 289         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 290          * rr->length bytes of encrypted compressed stuff. */
 291
 292         /* check is not needed I belive */
 293         if (rr->length > (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
 294                 {
 295                 al=SSL_AD_RECORD_OVERFLOW;
 296                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 297                 goto f_err;
 298                 }
 299
 300         /* decrypt in place in 'rr->input' */
 301         rr->data=rr->input;
 302
 303         if (!s->method->ssl3_enc->enc(s,0))
 304                 {
 305                 al=SSL_AD_DECRYPT_ERROR;
 306                 goto f_err;
 307                 }
 308 #ifdef TLS_DEBUG
 309 printf("dec %d\n",rr->length);
 310 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 311 printf("\n");
 312 #endif
 313         /* r->length is now the compressed data plus mac */
 314         if (    (sess == NULL) ||
 315                 (s->enc_read_ctx == NULL) ||
 316                 (s->read_hash == NULL))
 317                 clear=1;
 318
 319         if (!clear)
 320                 {
 321                 mac_size=EVP_MD_size(s->read_hash);
 322
 323                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
 324                         {
 325                         al=SSL_AD_RECORD_OVERFLOW;
 326                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
 327                         goto f_err;
 328                         }
 329                 /* check MAC for rr->input' */
 330                 if (rr->length < mac_size)
 331                         {
 332                         al=SSL_AD_DECODE_ERROR;
 333                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 334                         goto f_err;
 335                         }
 336                 rr->length-=mac_size;
 337                 i=s->method->ssl3_enc->mac(s,md,0);
 338                 if (memcmp(md,&(rr->data[rr->length]),mac_size) != 0)
 339                         {
 340                         al=SSL_AD_BAD_RECORD_MAC;
 341                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_MAC_DECODE);
 342                         ret= -1;
 343                         goto f_err;
 344                         }
 345                 }
 346
 347         /* r->length is now just compressed */
 348         if (s->expand != NULL)
 349                 {
 350                 if (rr->length >
 351                         (unsigned int)SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
 352                         {
 353                         al=SSL_AD_RECORD_OVERFLOW;
 354                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 355                         goto f_err;
 356                         }
 357                 if (!do_uncompress(s))
 358                         {
 359                         al=SSL_AD_DECOMPRESSION_FAILURE;
 360                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
 361                         goto f_err;
 362                         }
 363                 }
 364
 365         if (rr->length > (unsigned int)SSL3_RT_MAX_PLAIN_LENGTH+extra)
 366                 {
 367                 al=SSL_AD_RECORD_OVERFLOW;
 368                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 369                 goto f_err;
 370                 }
 371
 372         rr->off=0;
 373         /* So at this point the following is true
 374          * ssl->s3->rrec.type   is the type of record
 375          * ssl->s3->rrec.length == number of bytes in record
 376          * ssl->s3->rrec.off    == offset to first valid byte
 377          * ssl->s3->rrec.data   == where to take bytes from, increment
 378          *                         after use :-).
 379          */
 380
 381         /* we have pulled in a full packet so zero things */
 382         s->packet_length=0;
 383
 384         /* just read a 0 length packet */
 385         if (rr->length == 0) goto again;
 386
 387         return(1);
 388 f_err:
 389         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 390 err:
 391         return(ret);
 392         }
 393
 394 static int do_uncompress(SSL *ssl)
 395         {
 396         int i;
 397         SSL3_RECORD *rr;
 398
 399         rr= &(ssl->s3->rrec);
 400         i=COMP_expand_block(ssl->expand,rr->comp,
 401                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
 402         if (i < 0)
 403                 return(0);
 404         else
 405                 rr->length=i;
 406         rr->data=rr->comp;
 407
 408         return(1);
 409         }
 410
 411 static int do_compress(SSL *ssl)
 412         {
 413         int i;
 414         SSL3_RECORD *wr;
 415
 416         wr= &(ssl->s3->wrec);
 417         i=COMP_compress_block(ssl->compress,wr->data,
 418                 SSL3_RT_MAX_COMPRESSED_LENGTH,
 419                 wr->input,(int)wr->length);
 420         if (i < 0)
 421                 return(0);
 422         else
 423                 wr->length=i;
 424
 425         wr->input=wr->data;
 426         return(1);
 427         }
 428
 429 /* Call this to write data
 430  * It will return <= 0 if not all data has been sent or non-blocking IO.
 431  */
 432 int ssl3_write_bytes(SSL *s, int type, const void *_buf, int len)
 433         {
 434         const unsigned char *buf=_buf;
 435         unsigned int tot,n,nw;
 436         int i;
 437
 438         s->rwstate=SSL_NOTHING;
 439         tot=s->s3->wnum;
 440         s->s3->wnum=0;
 441
 442         if (SSL_in_init(s) && !s->in_handshake)
 443                 {
 444                 i=s->handshake_func(s);
 445                 if (i < 0) return(i);
 446                 if (i == 0)
 447                         {
 448                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 449                         return(-1);
 450                         }
 451                 }
 452
 453         n=(len-tot);
 454         for (;;)
 455                 {
 456                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
 457                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
 458                 else
 459                         nw=n;
 460
 461                 i=do_ssl3_write(s,type,&(buf[tot]),nw);
 462                 if (i <= 0)
 463                         {
 464                         s->s3->wnum=tot;
 465                         return(i);
 466                         }
 467
 468                 if (type == SSL3_RT_HANDSHAKE)
 469                         ssl3_finish_mac(s,&(buf[tot]),i);
 470
 471                 if ((i == (int)n) ||
 472                         (type == SSL3_RT_APPLICATION_DATA &&
 473                         (s->mode | SSL_MODE_ENABLE_PARTIAL_WRITE)))
 474                         {
 475                         return(tot+i);
 476                         }
 477
 478                 n-=i;
 479                 tot+=i;
 480                 }
 481         }
 482
 483 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 484                          unsigned int len)
 485         {
 486         unsigned char *p,*plen;
 487         int i,mac_size,clear=0;
 488         SSL3_RECORD *wr;
 489         SSL3_BUFFER *wb;
 490         SSL_SESSION *sess;
 491
 492         /* first check is there is a SSL3_RECORD still being written
 493          * out.  This will happen with non blocking IO */
 494         if (s->s3->wbuf.left != 0)
 495                 return(ssl3_write_pending(s,type,buf,len));
 496
 497         /* If we have an alert to send, lets send it */
 498         if (s->s3->alert_dispatch)
 499                 {
 500                 i=ssl3_dispatch_alert(s);
 501                 if (i <= 0)
 502                         return(i);
 503                 /* if it went, fall through and send more stuff */
 504                 }
 505
 506         if (len <= 0) return(len);
 507
 508         wr= &(s->s3->wrec);
 509         wb= &(s->s3->wbuf);
 510         sess=s->session;
 511
 512         if (    (sess == NULL) ||
 513                 (s->enc_write_ctx == NULL) ||
 514                 (s->write_hash == NULL))
 515                 clear=1;
 516
 517         if (clear)
 518                 mac_size=0;
 519         else
 520                 mac_size=EVP_MD_size(s->write_hash);
 521
 522         p=wb->buf;
 523
 524         /* write the header */
 525         *(p++)=type&0xff;
 526         wr->type=type;
 527
 528         *(p++)=(s->version>>8);
 529         *(p++)=s->version&0xff;
 530
 531         /* record where we are to write out packet length */
 532         plen=p;
 533         p+=2;
 534
 535         /* lets setup the record stuff. */
 536         wr->data=p;
 537         wr->length=(int)len;
 538         wr->input=(unsigned char *)buf;
 539
 540         /* we now 'read' from wr->input, wr->length bytes into
 541          * wr->data */
 542
 543         /* first we compress */
 544         if (s->compress != NULL)
 545                 {
 546                 if (!do_compress(s))
 547                         {
 548                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
 549                         goto err;
 550                         }
 551                 }
 552         else
 553                 {
 554                 memcpy(wr->data,wr->input,wr->length);
 555                 wr->input=wr->data;
 556                 }
 557
 558         /* we should still have the output to wr->data and the input
 559          * from wr->input.  Length should be wr->length.
 560          * wr->data still points in the wb->buf */
 561
 562         if (mac_size != 0)
 563                 {
 564                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
 565                 wr->length+=mac_size;
 566                 wr->input=p;
 567                 wr->data=p;
 568                 }
 569
 570         /* ssl3_enc can only have an error on read */
 571         s->method->ssl3_enc->enc(s,1);
 572
 573         /* record length after mac and block padding */
 574         s2n(wr->length,plen);
 575
 576         /* we should now have
 577          * wr->data pointing to the encrypted data, which is
 578          * wr->length long */
 579         wr->type=type; /* not needed but helps for debugging */
 580         wr->length+=SSL3_RT_HEADER_LENGTH;
 581
 582         /* Now lets setup wb */
 583         wb->left=wr->length;
 584         wb->offset=0;
 585
 586         s->s3->wpend_tot=len;
 587         s->s3->wpend_buf=buf;
 588         s->s3->wpend_type=type;
 589         s->s3->wpend_ret=len;
 590
 591         /* we now just need to write the buffer */
 592         return(ssl3_write_pending(s,type,buf,len));
 593 err:
 594         return(-1);
 595         }
 596
 597 /* if s->s3->wbuf.left != 0, we need to call this */
 598 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 599                               unsigned int len)
 600         {
 601         int i;
 602
 603 /* XXXX */
 604         if ((s->s3->wpend_tot > (int)len)
 605                 || ((s->s3->wpend_buf != buf) &&
 606                         (!s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
 607                 || (s->s3->wpend_type != type))
 608                 {
 609                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
 610                 return(-1);
 611                 }
 612
 613         for (;;)
 614                 {
 615                 clear_sys_error();
 616                 if (s->wbio != NULL)
 617                         {
 618                         s->rwstate=SSL_WRITING;
 619                         i=BIO_write(s->wbio,
 620                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
 621                                 (unsigned int)s->s3->wbuf.left);
 622                         }
 623                 else
 624                         {
 625                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 626                         i= -1;
 627                         }
 628                 if (i == s->s3->wbuf.left)
 629                         {
 630                         s->s3->wbuf.left=0;
 631                         s->rwstate=SSL_NOTHING;
 632                         return(s->s3->wpend_ret);
 633                         }
 634                 else if (i <= 0)
 635                         return(i);
 636                 s->s3->wbuf.offset+=i;
 637                 s->s3->wbuf.left-=i;
 638                 }
 639         }
 640
 641 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len)
 642         {
 643         int al,i,j,n,ret;
 644         SSL3_RECORD *rr;
 645         void (*cb)()=NULL;
 646         BIO *bio;
 647
 648         if (s->s3->rbuf.buf == NULL) /* Not initialize yet */
 649                 if (!ssl3_setup_buffers(s))
 650                         return(-1);
 651
 652         if (!s->in_handshake && SSL_in_init(s))
 653                 {
 654                 i=s->handshake_func(s);
 655                 if (i < 0) return(i);
 656                 if (i == 0)
 657                         {
 658                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 659                         return(-1);
 660                         }
 661                 }
 662 start:
 663         s->rwstate=SSL_NOTHING;
 664
 665         /* s->s3->rrec.type     - is the type of record
 666          * s->s3->rrec.data,    - data
 667          * s->s3->rrec.off,     - ofset into 'data' for next read
 668          * s->s3->rrec.length,  - number of bytes. */
 669         rr= &(s->s3->rrec);
 670
 671         /* get new packet */
 672         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 673                 {
 674                 ret=ssl3_get_record(s);
 675                 if (ret <= 0) return(ret);
 676                 }
 677
 678         /* we now have a packet which can be read and processed */
 679
 680         if (s->s3->change_cipher_spec && (rr->type != SSL3_RT_HANDSHAKE))
 681                 {
 682                 al=SSL_AD_UNEXPECTED_MESSAGE;
 683                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
 684                 goto err;
 685                 }
 686
 687         /* If the other end has shutdown, throw anything we read away */
 688         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 689                 {
 690                 rr->length=0;
 691                 s->rwstate=SSL_NOTHING;
 692                 return(0);
 693                 }
 694
 695         /* Check for an incoming 'Client Request' message */
 696         if ((rr->type == SSL3_RT_HANDSHAKE) && (rr->length == 4) &&
 697                 (rr->data[0] == SSL3_MT_CLIENT_REQUEST) &&
 698                 (s->session != NULL) && (s->session->cipher != NULL))
 699                 {
 700                 if ((rr->data[1] != 0) || (rr->data[2] != 0) ||
 701                         (rr->data[3] != 0))
 702                         {
 703                         al=SSL_AD_DECODE_ERROR;
 704                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CLIENT_REQUEST);
 705                         goto err;
 706                         }
 707
 708                 if (SSL_is_init_finished(s) &&
 709                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
 710                         !s->s3->renegotiate)
 711                         {
 712                         ssl3_renegotiate(s);
 713                         if (ssl3_renegotiate_check(s))
 714                                 {
 715                                 n=s->handshake_func(s);
 716                                 if (n < 0) return(n);
 717                                 if (n == 0)
 718                                         {
 719                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 720                                         return(-1);
 721                                         }
 722                                 }
 723                         }
 724                 rr->length=0;
 725 /* ZZZ */       goto start;
 726                 }
 727
 728         /* if it is not the type we want, or we have shutdown and want
 729          * the peer shutdown */
 730         if ((rr->type != type) || (s->shutdown & SSL_SENT_SHUTDOWN))
 731                 {
 732                 if (rr->type == SSL3_RT_ALERT)
 733                         {
 734                         if ((rr->length != 2) || (rr->off != 0))
 735                                 {
 736                                 al=SSL_AD_DECODE_ERROR;
 737                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_ALERT_RECORD);
 738                                 goto f_err;
 739                                 }
 740
 741                         i=rr->data[0];
 742                         n=rr->data[1];
 743
 744                         /* clear from buffer */
 745                         rr->length=0;
 746
 747                         if (s->info_callback != NULL)
 748                                 cb=s->info_callback;
 749                         else if (s->ctx->info_callback != NULL)
 750                                 cb=s->ctx->info_callback;
 751
 752                         if (cb != NULL)
 753                                 {
 754                                 j=(i<<8)|n;
 755                                 cb(s,SSL_CB_READ_ALERT,j);
 756                                 }
 757
 758                         if (i == 1)
 759                                 {
 760                                 s->s3->warn_alert=n;
 761                                 if (n == SSL_AD_CLOSE_NOTIFY)
 762                                         {
 763                                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
 764                                         return(0);
 765                                         }
 766                                 }
 767                         else if (i == 2)
 768                                 {
 769                                 char tmp[16];
 770
 771                                 s->rwstate=SSL_NOTHING;
 772                                 s->s3->fatal_alert=n;
 773                                 SSLerr(SSL_F_SSL3_READ_BYTES,
 774                                         SSL_AD_REASON_OFFSET+n);
 775                                 sprintf(tmp,"%d",n);
 776                                 ERR_add_error_data(2,"SSL alert number ",tmp);
 777                                 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
 778                                 SSL_CTX_remove_session(s->ctx,s->session);
 779                                 return(0);
 780                                 }
 781                         else
 782                                 {
 783                                 al=SSL_AD_ILLEGAL_PARAMETER;
 784                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
 785                                 goto f_err;
 786                                 }
 787
 788                         rr->length=0;
 789                         goto start;
 790                         }
 791
 792                 if (s->shutdown & SSL_SENT_SHUTDOWN)
 793                         {
 794                         s->rwstate=SSL_NOTHING;
 795                         rr->length=0;
 796                         return(0);
 797                         }
 798
 799                 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
 800                         {
 801                         if (    (rr->length != 1) || (rr->off != 0) ||
 802                                 (rr->data[0] != SSL3_MT_CCS))
 803                                 {
 804                                 i=SSL_AD_ILLEGAL_PARAMETER;
 805                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
 806                                 goto err;
 807                                 }
 808
 809                         rr->length=0;
 810                         s->s3->change_cipher_spec=1;
 811                         if (!do_change_cipher_spec(s))
 812                                 goto err;
 813                         else
 814                                 goto start;
 815                         }
 816
 817                 /* else we have a handshake */
 818                 if ((rr->type == SSL3_RT_HANDSHAKE) &&
 819                         !s->in_handshake)
 820                         {
 821                         if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
 822                                 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
 823                                 {
 824                                 s->state=SSL_ST_BEFORE|(s->server)
 825                                                 ?SSL_ST_ACCEPT
 826                                                 :SSL_ST_CONNECT;
 827                                 s->new_session=1;
 828                                 }
 829                         n=s->handshake_func(s);
 830                         if (n < 0) return(n);
 831                         if (n == 0)
 832                                 {
 833                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 834                                 return(-1);
 835                                 }
 836
 837                         /* In the case where we try to read application data
 838                          * the first time, but we trigger an SSL handshake, we
 839                          * return -1 with the retry option set.  I do this
 840                          * otherwise renegotiation can cause nasty problems
 841                          * in the non-blocking world */
 842
 843                         s->rwstate=SSL_READING;
 844                         bio=SSL_get_rbio(s);
 845                         BIO_clear_retry_flags(bio);
 846                         BIO_set_retry_read(bio);
 847                         return(-1);
 848                         }
 849
 850                 switch (rr->type)
 851                         {
 852                 default:
 853 #ifndef NO_TLS
 854                         /* TLS just ignores unknown message types */
 855                         if (s->version == TLS1_VERSION)
 856                                 {
 857                                 goto start;
 858                                 }
 859 #endif
 860                 case SSL3_RT_CHANGE_CIPHER_SPEC:
 861                 case SSL3_RT_ALERT:
 862                 case SSL3_RT_HANDSHAKE:
 863                         al=SSL_AD_UNEXPECTED_MESSAGE;
 864                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
 865                         goto f_err;
 866                 case SSL3_RT_APPLICATION_DATA:
 867                         /* At this point, we were expecting something else,
 868                          * but have application data.  What we do is set the
 869                          * error, and return -1.  On the way out, if the
 870                          * library was running inside ssl3_read() and it makes
 871                          * sense to read application data at this point, we
 872                          * will indulge it.  This will mostly happen during
 873                          * session renegotiation.
 874                          */
 875                         if (s->s3->in_read_app_data &&
 876                                 (s->s3->total_renegotiations != 0) &&
 877                                 ((
 878                                   (s->state & SSL_ST_CONNECT) &&
 879                                   (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
 880                                   (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
 881                                  ) || (
 882                                   (s->state & SSL_ST_ACCEPT) &&
 883                                   (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
 884                                   (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
 885                                  )
 886                                 ))
 887                                 {
 888                                 s->s3->in_read_app_data=0;
 889                                 return(-1);
 890                                 }
 891                         else
 892                                 {
 893                                 al=SSL_AD_UNEXPECTED_MESSAGE;
 894                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
 895                                 goto f_err;
 896                                 }
 897                         }
 898                 }
 899
 900         /* make sure that we are not getting application data when we
 901          * are doing a handshake for the first time */
 902         if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 903                 (s->enc_read_ctx == NULL))
 904                 {
 905                 al=SSL_AD_UNEXPECTED_MESSAGE;
 906                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 907                 goto f_err;
 908                 }
 909
 910         if (len <= 0) return(len);
 911
 912         if ((unsigned int)len > rr->length)
 913                 n=rr->length;
 914         else
 915                 n=len;
 916
 917         memcpy(buf,&(rr->data[rr->off]),(unsigned int)n);
 918         rr->length-=n;
 919         rr->off+=n;
 920         if (rr->length <= 0)
 921                 {
 922                 s->rstate=SSL_ST_READ_HEADER;
 923                 rr->off=0;
 924                 }
 925
 926         if (type == SSL3_RT_HANDSHAKE)
 927                 ssl3_finish_mac(s,buf,n);
 928         return(n);
 929 f_err:
 930         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 931 err:
 932         return(-1);
 933         }
 934
 935 static int do_change_cipher_spec(SSL *s)
 936         {
 937         int i;
 938         unsigned char *sender;
 939         int slen;
 940
 941         if (s->state & SSL_ST_ACCEPT)
 942                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
 943         else
 944                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
 945
 946         if (s->s3->tmp.key_block == NULL)
 947                 {
 948                 s->session->cipher=s->s3->tmp.new_cipher;
 949                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
 950                 }
 951
 952         if (!s->method->ssl3_enc->change_cipher_state(s,i))
 953                 return(0);
 954
 955         /* we have to record the message digest at
 956          * this point so we can get it before we read
 957          * the finished message */
 958         if (s->state & SSL_ST_CONNECT)
 959                 {
 960                 sender=s->method->ssl3_enc->server_finished;
 961                 slen=s->method->ssl3_enc->server_finished_len;
 962                 }
 963         else
 964                 {
 965                 sender=s->method->ssl3_enc->client_finished;
 966                 slen=s->method->ssl3_enc->client_finished_len;
 967                 }
 968
 969         s->method->ssl3_enc->final_finish_mac(s,
 970                 &(s->s3->finish_dgst1),
 971                 &(s->s3->finish_dgst2),
 972                 sender,slen,&(s->s3->tmp.finish_md[0]));
 973
 974         return(1);
 975         }
 976
 977 int ssl3_do_write(SSL *s, int type)
 978         {
 979         int ret;
 980
 981         ret=ssl3_write_bytes(s,type,&s->init_buf->data[s->init_off],
 982                              s->init_num);
 983         if (ret == s->init_num)
 984                 return(1);
 985         if (ret < 0) return(-1);
 986         s->init_off+=ret;
 987         s->init_num-=ret;
 988         return(0);
 989         }
 990
 991 void ssl3_send_alert(SSL *s, int level, int desc)
 992         {
 993         /* Map tls/ssl alert value to correct one */
 994         desc=s->method->ssl3_enc->alert_value(desc);
 995         if (desc < 0) return;
 996         /* If a fatal one, remove from cache */
 997         if ((level == 2) && (s->session != NULL))
 998                 SSL_CTX_remove_session(s->ctx,s->session);
 999
1000         s->s3->alert_dispatch=1;
1001         s->s3->send_alert[0]=level;
1002         s->s3->send_alert[1]=desc;
1003         if (s->s3->wbuf.left == 0) /* data still being written out */
1004                 ssl3_dispatch_alert(s);
1005         /* else data is still being written out, we will get written
1006          * some time in the future */
1007         }
1008
1009 int ssl3_dispatch_alert(SSL *s)
1010         {
1011         int i,j;
1012         void (*cb)()=NULL;
1013
1014         s->s3->alert_dispatch=0;
1015         i=do_ssl3_write(s,SSL3_RT_ALERT,&s->s3->send_alert[0],2);
1016         if (i <= 0)
1017                 {
1018                 s->s3->alert_dispatch=1;
1019                 }
1020         else
1021                 {
1022                 /* If it is important, send it now.  If the message
1023                  * does not get sent due to non-blocking IO, we will
1024                  * not worry too much. */
1025                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1026                         (void)BIO_flush(s->wbio);
1027
1028                 if (s->info_callback != NULL)
1029                         cb=s->info_callback;
1030                 else if (s->ctx->info_callback != NULL)
1031                         cb=s->ctx->info_callback;
1032
1033                 if (cb != NULL)
1034                         {
1035                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1036                         cb(s,SSL_CB_WRITE_ALERT,j);
1037                         }
1038                 }
1039         return(i);
1040         }
1041