3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
6 /* ====================================================================
7 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
21 * 3. All advertising materials mentioning features or use of this
22 * software must display the following acknowledgment:
23 * "This product includes software developed by the OpenSSL Project
24 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 * endorse or promote products derived from this software without
28 * prior written permission. For written permission, please contact
29 * openssl-core@openssl.org.
31 * 5. Products derived from this software may not be called "OpenSSL"
32 * nor may "OpenSSL" appear in their names without prior written
33 * permission of the OpenSSL Project.
35 * 6. Redistributions of any form whatsoever must retain the following
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com). This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60 * All rights reserved.
62 * This package is an SSL implementation written
63 * by Eric Young (eay@cryptsoft.com).
64 * The implementation was written so as to conform with Netscapes SSL.
66 * This library is free for commercial and non-commercial use as long as
67 * the following conditions are aheared to. The following conditions
68 * apply to all code found in this distribution, be it the RC4, RSA,
69 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
70 * included with this distribution is covered by the same copyright terms
71 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
73 * Copyright remains Eric Young's, and as such any Copyright notices in
74 * the code are not to be removed.
75 * If this package is used in a product, Eric Young should be given attribution
76 * as the author of the parts of the library used.
77 * This can be in the form of a textual message at program startup or
78 * in documentation (online or textual) provided with the package.
80 * Redistribution and use in source and binary forms, with or without
81 * modification, are permitted provided that the following conditions
83 * 1. Redistributions of source code must retain the copyright
84 * notice, this list of conditions and the following disclaimer.
85 * 2. Redistributions in binary form must reproduce the above copyright
86 * notice, this list of conditions and the following disclaimer in the
87 * documentation and/or other materials provided with the distribution.
88 * 3. All advertising materials mentioning features or use of this software
89 * must display the following acknowledgement:
90 * "This product includes cryptographic software written by
91 * Eric Young (eay@cryptsoft.com)"
92 * The word 'cryptographic' can be left out if the rouines from the library
93 * being used are not cryptographic related :-).
94 * 4. If you include any Windows specific code (or a derivative thereof) from
95 * the apps directory (application code) you must include an acknowledgement:
96 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
98 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
110 * The licence and distribution terms for any publically available version or
111 * derivative of this code cannot be changed. i.e. this code cannot simply be
112 * copied and put under another distribution licence
113 * [including the GNU Public Licence.]
119 #include "ssl_locl.h"
120 #include <openssl/buffer.h>
121 #include <openssl/rand.h>
122 #include <openssl/objects.h>
123 #include <openssl/evp.h>
124 #include <openssl/x509.h>
127 /* XDTLS: figure out the right values */
128 static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28};
130 static unsigned int dtls1_min_mtu(void);
131 static unsigned int dtls1_guess_mtu(unsigned int curr_mtu);
132 static void dtls1_fix_message_header(SSL *s, unsigned long frag_off,
133 unsigned long frag_len);
134 static unsigned char *dtls1_write_message_header(SSL *s,
136 static void dtls1_set_message_header_int(SSL *s, unsigned char mt,
137 unsigned long len, unsigned short seq_num, unsigned long frag_off,
138 unsigned long frag_len);
139 static int dtls1_retransmit_buffered_messages(SSL *s);
140 static long dtls1_get_message_fragment(SSL *s, int st1, int stn,
142 static void dtls1_process_handshake_fragment(SSL *s, int frag_len);
145 dtls1_hm_fragment_new(unsigned long frag_len)
147 hm_fragment *frag = NULL;
148 unsigned char *buf = NULL;
150 frag = (hm_fragment *)OPENSSL_malloc(sizeof(hm_fragment));
154 buf = (unsigned char *)OPENSSL_malloc(frag_len
155 + DTLS1_HM_HEADER_LENGTH);
162 frag->fragment = buf;
168 dtls1_hm_fragment_free(hm_fragment *frag)
170 OPENSSL_free(frag->fragment);
174 /* send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */
175 int dtls1_do_write(SSL *s, int type)
179 unsigned int len, frag_off;
181 /* AHA! Figure out the MTU, and stick to the right size */
182 if ( ! (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU))
185 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
187 /* I've seen the kernel return bogus numbers when it doesn't know
188 * (initial write), so just make sure we have a reasonable number */
189 if ( s->d1->mtu < dtls1_min_mtu())
192 s->d1->mtu = dtls1_guess_mtu(s->d1->mtu);
193 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU,
200 fprintf(stderr, "using MTU = %d\n", mtu);
202 mtu -= (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH);
204 curr_mtu = mtu - BIO_wpending(SSL_get_wbio(s));
208 else if ( ( ret = BIO_flush(SSL_get_wbio(s))) <= 0)
211 if ( BIO_wpending(SSL_get_wbio(s)) + s->init_num >= mtu)
213 ret = BIO_flush(SSL_get_wbio(s));
216 mtu = s->d1->mtu - (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH);
219 OPENSSL_assert(mtu > 0); /* should have something reasonable now */
223 if ( s->init_off == 0 && type == SSL3_RT_HANDSHAKE)
224 OPENSSL_assert(s->init_num ==
225 (int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH);
230 curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) -
231 DTLS1_RT_HEADER_LENGTH;
233 if ( curr_mtu <= DTLS1_HM_HEADER_LENGTH)
235 /* grr.. we could get an error if MTU picked was wrong */
236 ret = BIO_flush(SSL_get_wbio(s));
239 curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH;
242 if ( s->init_num > curr_mtu)
248 /* XDTLS: this function is too long. split out the CCS part */
249 if ( type == SSL3_RT_HANDSHAKE)
251 if ( s->init_off != 0)
253 OPENSSL_assert(s->init_off > DTLS1_HM_HEADER_LENGTH);
254 s->init_off -= DTLS1_HM_HEADER_LENGTH;
255 s->init_num += DTLS1_HM_HEADER_LENGTH;
257 /* write atleast DTLS1_HM_HEADER_LENGTH bytes */
258 if ( len <= DTLS1_HM_HEADER_LENGTH)
259 len += DTLS1_HM_HEADER_LENGTH;
262 dtls1_fix_message_header(s, frag_off,
263 len - DTLS1_HM_HEADER_LENGTH);
265 dtls1_write_message_header(s, (unsigned char *)&s->init_buf->data[s->init_off]);
267 OPENSSL_assert(len >= DTLS1_HM_HEADER_LENGTH);
270 ret=dtls1_write_bytes(s,type,&s->init_buf->data[s->init_off],
274 /* might need to update MTU here, but we don't know
275 * which previous packet caused the failure -- so can't
276 * really retransmit anything. continue as if everything
277 * is fine and wait for an alert to handle the
280 if ( BIO_ctrl(SSL_get_wbio(s),
281 BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL))
282 s->d1->mtu = BIO_ctrl(SSL_get_wbio(s),
283 BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
290 /* bad if this assert fails, only part of the handshake
291 * message got sent. but why would this happen? */
292 OPENSSL_assert(len == (unsigned int)ret);
294 if (type == SSL3_RT_HANDSHAKE && ! s->d1->retransmitting)
295 /* should not be done for 'Hello Request's, but in that case
296 * we'll ignore the result anyway */
298 (unsigned char *)&s->init_buf->data[s->init_off +
299 DTLS1_HM_HEADER_LENGTH], ret - DTLS1_HM_HEADER_LENGTH);
301 if (ret == s->init_num)
304 s->msg_callback(1, s->version, type, s->init_buf->data,
305 (size_t)(s->init_off + s->init_num), s,
306 s->msg_callback_arg);
308 s->init_off = 0; /* done writing this message */
315 frag_off += (ret -= DTLS1_HM_HEADER_LENGTH);
322 /* Obtain handshake message of message type 'mt' (any if mt == -1),
323 * maximum acceptable body length 'max'.
324 * Read an entire handshake message. Handshake messages arrive in
327 long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok)
331 /* s3->tmp is used to store messages that are unexpected, caused
332 * by the absence of an optional handshake message */
333 if (s->s3->tmp.reuse_message)
335 s->s3->tmp.reuse_message=0;
336 if ((mt >= 0) && (s->s3->tmp.message_type != mt))
338 al=SSL_AD_UNEXPECTED_MESSAGE;
339 SSLerr(SSL_F_DTLS1_GET_MESSAGE,SSL_R_UNEXPECTED_MESSAGE);
343 s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH;
344 s->init_num = (int)s->s3->tmp.message_size;
350 if ( s->d1->r_msg_hdr.frag_off == 0)
352 /* s->d1->r_message_header.msg_len = 0; */
353 memset(&(s->d1->r_msg_hdr), 0x00, sizeof(struct hm_header_st));
356 i = dtls1_get_message_fragment(s, st1, stn, max, ok);
357 if ( i == DTLS1_HM_BAD_FRAGMENT ||
358 i == DTLS1_HM_FRAGMENT_RETRY) /* bad fragment received */
360 else if ( i <= 0 && !*ok)
363 if (s->d1->r_msg_hdr.msg_len == (unsigned int)s->init_num - DTLS1_HM_HEADER_LENGTH)
365 memset(&(s->d1->r_msg_hdr), 0x00, sizeof(struct hm_header_st));
367 s->d1->handshake_read_seq++;
368 /* we just read a handshake message from the other side:
369 * this means that we don't need to retransmit of the
371 * XDTLS: may be able clear out this
372 * buffer a little sooner (i.e if an out-of-order
373 * handshake message/record is received at the record
375 * XDTLS: exception is that the server needs to
376 * know that change cipher spec and finished messages
377 * have been received by the client before clearing this
378 * buffer. this can simply be done by waiting for the
379 * first data segment, but is there a better way? */
380 dtls1_clear_record_buffer(s);
382 s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH;
383 return s->init_num - DTLS1_HM_HEADER_LENGTH;
386 s->d1->r_msg_hdr.frag_off = i;
390 ssl3_send_alert(s,SSL3_AL_FATAL,al);
397 dtls1_retrieve_buffered_fragment(SSL *s, unsigned long *copied)
399 /* (0) check whether the desired fragment is available
401 * (1) copy over the fragment to s->init_buf->data[]
402 * (2) update s->init_num
406 unsigned long overlap;
409 item = pqueue_peek(s->d1->buffered_messages);
413 frag = (hm_fragment *)item->data;
415 if ( s->d1->handshake_read_seq == frag->msg_header.seq &&
416 frag->msg_header.frag_off <= (unsigned int)s->init_num - DTLS1_HM_HEADER_LENGTH)
418 pqueue_pop(s->d1->buffered_messages);
419 overlap = s->init_num - DTLS1_HM_HEADER_LENGTH
420 - frag->msg_header.frag_off;
424 memcpy(&s->init_buf->data[s->init_num],
425 p + DTLS1_HM_HEADER_LENGTH + overlap,
426 frag->msg_header.frag_len - overlap);
428 OPENSSL_free(frag->fragment);
432 *copied = frag->msg_header.frag_len - overlap;
441 dtls1_buffer_handshake_fragment(SSL *s, struct hm_header_st* msg_hdr)
443 hm_fragment *frag = NULL;
445 unsigned char seq64be[8];
447 frag = dtls1_hm_fragment_new(msg_hdr->frag_len);
451 memcpy(frag->fragment, &(s->init_buf->data[s->init_num]),
452 msg_hdr->frag_len + DTLS1_HM_HEADER_LENGTH);
454 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr));
456 memset(seq64be,0,sizeof(seq64be));
457 seq64be[6] = (unsigned char)(msg_hdr->seq>>8);
458 seq64be[7] = (unsigned char)(msg_hdr->seq);
460 item = pitem_new(seq64be, frag);
464 pqueue_insert(s->d1->buffered_messages, item);
468 if ( frag != NULL) dtls1_hm_fragment_free(frag);
469 if ( item != NULL) OPENSSL_free(item);
475 dtls1_process_handshake_fragment(SSL *s, int frag_len)
479 p = (unsigned char *)s->init_buf->data;
481 ssl3_finish_mac(s, &p[s->init_num - frag_len], frag_len);
486 dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st *msg_hdr, int *ok)
491 /* make sure there's enough room to read this fragment */
492 if ( (int)msg_hdr->frag_len && !BUF_MEM_grow_clean(s->init_buf,
493 (int)msg_hdr->frag_len + DTLS1_HM_HEADER_LENGTH + s->init_num))
495 SSLerr(SSL_F_DTLS1_PROCESS_OUT_OF_SEQ_MESSAGE,ERR_R_BUF_LIB);
499 p = (unsigned char *)s->init_buf->data;
501 /* read the body of the fragment (header has already been read */
502 if ( msg_hdr->frag_len > 0)
504 i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,
506 msg_hdr->frag_len,0);
514 if ( msg_hdr->seq > s->d1->handshake_read_seq)
515 dtls1_buffer_handshake_fragment(s, msg_hdr);
517 OPENSSL_assert(msg_hdr->seq < s->d1->handshake_read_seq);
519 return DTLS1_HM_FRAGMENT_RETRY;
527 dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, int *ok)
530 unsigned long l, frag_off, frag_len;
532 struct hm_header_st msg_hdr;
533 unsigned long overlap;
535 /* see if we have the required fragment already */
536 if (dtls1_retrieve_buffered_fragment(s, &l))
538 /* compute MAC, remove fragment headers */
539 dtls1_process_handshake_fragment(s, l);
540 s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH;
545 /* get a handshake fragment from the record layer */
546 p = (unsigned char *)s->init_buf->data;
548 /* read handshake message header */
549 i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,&p[s->init_num],
550 DTLS1_HM_HEADER_LENGTH, 0);
551 if (i <= 0) /* nbio, or an error */
553 s->rwstate=SSL_READING;
558 OPENSSL_assert(i == DTLS1_HM_HEADER_LENGTH);
561 /* parse the message fragment header */
563 dtls1_get_message_header(p, &msg_hdr);
566 * if this is a future (or stale) message it gets buffered
567 * (or dropped)--no further processing at this time
569 if ( msg_hdr.seq != s->d1->handshake_read_seq)
570 return dtls1_process_out_of_seq_message(s, &msg_hdr, ok);
573 frag_off = msg_hdr.frag_off;
574 frag_len = msg_hdr.frag_len;
576 /* sanity checking */
577 if ( frag_off + frag_len > l)
579 al=SSL_AD_ILLEGAL_PARAMETER;
580 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE);
584 if (!s->server && s->d1->r_msg_hdr.frag_off == 0 &&
585 p[0] == SSL3_MT_HELLO_REQUEST)
587 /* The server may always send 'Hello Request' messages --
588 * we are doing a handshake anyway now, so ignore them
589 * if their format is correct. Does not count for
591 if (p[1] == 0 && p[2] == 0 &&p[3] == 0)
594 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
595 p, DTLS1_HM_HEADER_LENGTH, s,
596 s->msg_callback_arg);
599 return dtls1_get_message_fragment(s, st1, stn,
602 else /* Incorrectly formated Hello request */
604 al=SSL_AD_UNEXPECTED_MESSAGE;
605 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_UNEXPECTED_MESSAGE);
610 /* XDTLS: do a sanity check on the fragment */
614 if ( s->d1->r_msg_hdr.frag_off == 0) /* first fragment */
616 /* BUF_MEM_grow takes an 'int' parameter */
617 if (l > (INT_MAX-DTLS1_HM_HEADER_LENGTH))
619 al=SSL_AD_ILLEGAL_PARAMETER;
620 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE);
623 if (l && !BUF_MEM_grow_clean(s->init_buf,(int)l
624 + DTLS1_HM_HEADER_LENGTH))
626 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,ERR_R_BUF_LIB);
629 /* Only do this test when we're reading the expected message.
630 * Stale messages will be dropped and future messages will be buffered */
631 if ( l > (unsigned long)max)
633 al=SSL_AD_ILLEGAL_PARAMETER;
634 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE);
638 s->s3->tmp.message_size=l;
641 if ( frag_len > (unsigned long)max)
643 al=SSL_AD_ILLEGAL_PARAMETER;
644 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE);
647 if ( frag_len + s->init_num > (INT_MAX - DTLS1_HM_HEADER_LENGTH))
649 al=SSL_AD_ILLEGAL_PARAMETER;
650 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE);
654 if ( frag_len & !BUF_MEM_grow_clean(s->init_buf, (int)frag_len
655 + DTLS1_HM_HEADER_LENGTH + s->init_num))
657 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,ERR_R_BUF_LIB);
661 if ( s->d1->r_msg_hdr.frag_off == 0)
663 s->s3->tmp.message_type = msg_hdr.type;
664 s->d1->r_msg_hdr.type = msg_hdr.type;
665 s->d1->r_msg_hdr.msg_len = l;
666 /* s->d1->r_msg_hdr.seq = seq_num; */
669 /* XDTLS: ressurect this when restart is in place */
672 /* next state (stn) */
673 p = (unsigned char *)s->init_buf->data;
677 i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,
680 /* XDTLS: fix this--message fragments cannot span multiple packets */
683 s->rwstate=SSL_READING;
691 /* XDTLS: an incorrectly formatted fragment should cause the
692 * handshake to fail */
693 OPENSSL_assert(i == (int)frag_len);
696 /* Successfully read a fragment.
697 * It may be (1) out of order, or
698 * (2) it's a repeat, in which case we dump it
699 * (3) the one we are expecting next (maybe with overlap)
700 * If it is next one, it may overlap with previously read bytes
703 /* case (1): buffer the future fragment
704 * (we can treat fragments from a future message the same
705 * as future fragments from the message being currently read, since
706 * they are sematically simply out of order.
708 if ( msg_hdr.seq > s->d1->handshake_read_seq ||
709 frag_off > s->init_num - DTLS1_HM_HEADER_LENGTH)
711 dtls1_buffer_handshake_fragment(s, &msg_hdr);
712 return DTLS1_HM_FRAGMENT_RETRY;
715 /* case (2): drop the entire fragment, and try again */
716 if ( msg_hdr.seq < s->d1->handshake_read_seq ||
717 frag_off + frag_len < s->init_num - DTLS1_HM_HEADER_LENGTH)
719 s->init_num -= DTLS1_HM_HEADER_LENGTH;
720 return DTLS1_HM_FRAGMENT_RETRY;
724 /* case (3): received a immediately useful fragment. Determine the
725 * possible overlap and copy the fragment.
727 overlap = (s->init_num - DTLS1_HM_HEADER_LENGTH) - frag_off;
729 /* retain the header for the first fragment */
730 if ( s->init_num > DTLS1_HM_HEADER_LENGTH)
732 memmove(&(s->init_buf->data[s->init_num]),
733 &(s->init_buf->data[s->init_num + DTLS1_HM_HEADER_LENGTH + overlap]),
736 s->init_num += frag_len - overlap;
739 s->init_num += frag_len;
741 dtls1_process_handshake_fragment(s, frag_len - overlap);
744 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->init_buf->data,
745 (size_t)s->init_num, s,
746 s->msg_callback_arg);
752 ssl3_send_alert(s,SSL3_AL_FATAL,al);
759 int dtls1_send_finished(SSL *s, int a, int b, const char *sender, int slen)
767 d=(unsigned char *)s->init_buf->data;
768 p= &(d[DTLS1_HM_HEADER_LENGTH]);
770 i=s->method->ssl3_enc->final_finish_mac(s,
771 &(s->s3->finish_dgst1),
772 &(s->s3->finish_dgst2),
773 sender,slen,s->s3->tmp.finish_md);
774 s->s3->tmp.finish_md_len = i;
775 memcpy(p, s->s3->tmp.finish_md, i);
779 #ifdef OPENSSL_SYS_WIN16
780 /* MSVC 1.5 does not clear the top bytes of the word unless
786 d = dtls1_set_message_header(s, d, SSL3_MT_FINISHED, l, 0, l);
787 s->init_num=(int)l+DTLS1_HM_HEADER_LENGTH;
790 /* buffer the message to handle re-xmits */
791 dtls1_buffer_message(s, 0);
796 /* SSL3_ST_SEND_xxxxxx_HELLO_B */
797 return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
800 /* for these 2 messages, we need to
801 * ssl->enc_read_ctx re-init
802 * ssl->s3->read_sequence zero
803 * ssl->s3->read_mac_secret re-init
804 * ssl->session->read_sym_enc assign
805 * ssl->session->read_compression assign
806 * ssl->session->read_hash assign
808 int dtls1_send_change_cipher_spec(SSL *s, int a, int b)
814 p=(unsigned char *)s->init_buf->data;
816 s->d1->handshake_write_seq = s->d1->next_handshake_write_seq;
817 s->d1->next_handshake_write_seq++;
818 s2n(s->d1->handshake_write_seq,p);
820 s->init_num=DTLS1_CCS_HEADER_LENGTH;
823 dtls1_set_message_header_int(s, SSL3_MT_CCS, 0,
824 s->d1->handshake_write_seq, 0, 0);
826 /* buffer the message to handle re-xmits */
827 dtls1_buffer_message(s, 1);
832 /* SSL3_ST_CW_CHANGE_B */
833 return(dtls1_do_write(s,SSL3_RT_CHANGE_CIPHER_SPEC));
836 unsigned long dtls1_output_cert_chain(SSL *s, X509 *x)
840 unsigned long l= 3 + DTLS1_HM_HEADER_LENGTH;
842 X509_STORE_CTX xs_ctx;
845 /* TLSv1 sends a chain with nothing in it, instead of an alert */
847 if (!BUF_MEM_grow_clean(buf,10))
849 SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB);
854 if(!X509_STORE_CTX_init(&xs_ctx,s->ctx->cert_store,NULL,NULL))
856 SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_X509_LIB);
863 if (!BUF_MEM_grow_clean(buf,(int)(n+l+3)))
865 SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB);
868 p=(unsigned char *)&(buf->data[l]);
872 if (X509_NAME_cmp(X509_get_subject_name(x),
873 X509_get_issuer_name(x)) == 0) break;
875 i=X509_STORE_get_by_subject(&xs_ctx,X509_LU_X509,
876 X509_get_issuer_name(x),&obj);
879 /* Count is one too high since the X509_STORE_get uped the
884 X509_STORE_CTX_cleanup(&xs_ctx);
887 /* Thawte special :-) */
888 if (s->ctx->extra_certs != NULL)
889 for (i=0; i<sk_X509_num(s->ctx->extra_certs); i++)
891 x=sk_X509_value(s->ctx->extra_certs,i);
893 if (!BUF_MEM_grow_clean(buf,(int)(n+l+3)))
895 SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB);
898 p=(unsigned char *)&(buf->data[l]);
904 l-= (3 + DTLS1_HM_HEADER_LENGTH);
906 p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);
909 p=(unsigned char *)&(buf->data[0]);
910 p = dtls1_set_message_header(s, p, SSL3_MT_CERTIFICATE, l, 0, l);
912 l+=DTLS1_HM_HEADER_LENGTH;
916 int dtls1_read_failed(SSL *s, int code)
924 fprintf( stderr, "invalid state reached %s:%d", __FILE__, __LINE__);
928 bio = SSL_get_rbio(s);
929 if ( ! BIO_dgram_recv_timedout(bio))
931 /* not a timeout, none of our business,
932 let higher layers handle this. in fact it's probably an error */
936 if ( ! SSL_in_init(s)) /* done, no need to send a retransmit */
938 BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ);
943 state->timeout.num_alerts++;
944 if ( state->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT)
946 /* fail the connection, enough alerts have been sent */
947 SSLerr(SSL_F_DTLS1_READ_FAILED,SSL_R_READ_TIMEOUT_EXPIRED);
951 state->timeout.read_timeouts++;
952 if ( state->timeout.read_timeouts > DTLS1_TMO_READ_COUNT)
955 state->timeout.read_timeouts = 1;
959 #if 0 /* for now, each alert contains only one record number */
960 item = pqueue_peek(state->rcvd_records);
963 /* send an alert immediately for all the missing records */
968 #if 0 /* no more alert sending, just retransmit the last set of messages */
970 ssl3_send_alert(s,SSL3_AL_WARNING,
971 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
974 return dtls1_retransmit_buffered_messages(s) ;
979 dtls1_retransmit_buffered_messages(SSL *s)
981 pqueue sent = s->d1->sent_messages;
987 iter = pqueue_iterator(sent);
989 for ( item = pqueue_next(&iter); item != NULL; item = pqueue_next(&iter))
991 frag = (hm_fragment *)item->data;
992 if ( dtls1_retransmit_message(s, frag->msg_header.seq, 0, &found) <= 0 &&
995 fprintf(stderr, "dtls1_retransmit_message() failed\n");
1004 static dtls1_message_buffer *
1005 dtls1_message_buffer_new(unsigned int len)
1007 dtls1_message_buffer *msg_buf;
1009 msg_buf = (dtls1_message_buffer *)
1010 OPENSSL_malloc(sizeof(dtls1_message_buffer));
1011 if ( msg_buf == NULL)
1014 memset(msg_buf, 0x00, sizeof(dtls1_message_buffer));
1016 msg_buf->data = (unsigned char *) OPENSSL_malloc(len);
1017 if ( msg_buf->data == NULL)
1019 OPENSSL_free(msg_buf);
1023 memset(msg_buf->data, 0x00, len);
1030 dtls1_message_buffer_free(dtls1_message_buffer *msg_buf)
1032 if (msg_buf != NULL)
1034 OPENSSL_free(msg_buf->data);
1035 OPENSSL_free(msg_buf);
1041 dtls1_buffer_message(SSL *s, int is_ccs)
1045 unsigned char seq64be[8];
1047 /* this function is called immediately after a message has
1048 * been serialized */
1049 OPENSSL_assert(s->init_off == 0);
1051 frag = dtls1_hm_fragment_new(s->init_num);
1053 memcpy(frag->fragment, s->init_buf->data, s->init_num);
1057 OPENSSL_assert(s->d1->w_msg_hdr.msg_len +
1058 DTLS1_CCS_HEADER_LENGTH == (unsigned int)s->init_num);
1062 OPENSSL_assert(s->d1->w_msg_hdr.msg_len +
1063 DTLS1_HM_HEADER_LENGTH == (unsigned int)s->init_num);
1066 frag->msg_header.msg_len = s->d1->w_msg_hdr.msg_len;
1067 frag->msg_header.seq = s->d1->w_msg_hdr.seq;
1068 frag->msg_header.type = s->d1->w_msg_hdr.type;
1069 frag->msg_header.frag_off = 0;
1070 frag->msg_header.frag_len = s->d1->w_msg_hdr.msg_len;
1071 frag->msg_header.is_ccs = is_ccs;
1073 memset(seq64be,0,sizeof(seq64be));
1074 seq64be[6] = (unsigned char)(frag->msg_header.seq>>8);
1075 seq64be[7] = (unsigned char)(frag->msg_header.seq);
1077 item = pitem_new(seq64be, frag);
1080 dtls1_hm_fragment_free(frag);
1085 fprintf( stderr, "buffered messge: \ttype = %xx\n", msg_buf->type);
1086 fprintf( stderr, "\t\t\t\t\tlen = %d\n", msg_buf->len);
1087 fprintf( stderr, "\t\t\t\t\tseq_num = %d\n", msg_buf->seq_num);
1090 pqueue_insert(s->d1->sent_messages, item);
1095 dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off,
1099 /* XDTLS: for now assuming that read/writes are blocking */
1102 unsigned long header_length;
1103 unsigned char seq64be[8];
1106 OPENSSL_assert(s->init_num == 0);
1107 OPENSSL_assert(s->init_off == 0);
1110 /* XDTLS: the requested message ought to be found, otherwise error */
1111 memset(seq64be,0,sizeof(seq64be));
1112 seq64be[6] = (unsigned char)(seq>>8);
1113 seq64be[7] = (unsigned char)seq;
1115 item = pqueue_find(s->d1->sent_messages, seq64be);
1118 fprintf(stderr, "retransmit: message %d non-existant\n", seq);
1124 frag = (hm_fragment *)item->data;
1126 if ( frag->msg_header.is_ccs)
1127 header_length = DTLS1_CCS_HEADER_LENGTH;
1129 header_length = DTLS1_HM_HEADER_LENGTH;
1131 memcpy(s->init_buf->data, frag->fragment,
1132 frag->msg_header.msg_len + header_length);
1133 s->init_num = frag->msg_header.msg_len + header_length;
1135 dtls1_set_message_header_int(s, frag->msg_header.type,
1136 frag->msg_header.msg_len, frag->msg_header.seq, 0,
1137 frag->msg_header.frag_len);
1139 s->d1->retransmitting = 1;
1140 ret = dtls1_do_write(s, frag->msg_header.is_ccs ?
1141 SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE);
1142 s->d1->retransmitting = 0;
1144 BIO_flush(SSL_get_wbio(s));
1148 /* call this function when the buffered messages are no longer needed */
1150 dtls1_clear_record_buffer(SSL *s)
1154 for(item = pqueue_pop(s->d1->sent_messages);
1155 item != NULL; item = pqueue_pop(s->d1->sent_messages))
1157 dtls1_hm_fragment_free((hm_fragment *)item->data);
1164 dtls1_set_message_header(SSL *s, unsigned char *p, unsigned char mt,
1165 unsigned long len, unsigned long frag_off, unsigned long frag_len)
1169 s->d1->handshake_write_seq = s->d1->next_handshake_write_seq;
1170 s->d1->next_handshake_write_seq++;
1173 dtls1_set_message_header_int(s, mt, len, s->d1->handshake_write_seq,
1174 frag_off, frag_len);
1176 return p += DTLS1_HM_HEADER_LENGTH;
1180 /* don't actually do the writing, wait till the MTU has been retrieved */
1182 dtls1_set_message_header_int(SSL *s, unsigned char mt,
1183 unsigned long len, unsigned short seq_num, unsigned long frag_off,
1184 unsigned long frag_len)
1186 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr;
1189 msg_hdr->msg_len = len;
1190 msg_hdr->seq = seq_num;
1191 msg_hdr->frag_off = frag_off;
1192 msg_hdr->frag_len = frag_len;
1196 dtls1_fix_message_header(SSL *s, unsigned long frag_off,
1197 unsigned long frag_len)
1199 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr;
1201 msg_hdr->frag_off = frag_off;
1202 msg_hdr->frag_len = frag_len;
1205 static unsigned char *
1206 dtls1_write_message_header(SSL *s, unsigned char *p)
1208 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr;
1210 *p++ = msg_hdr->type;
1211 l2n3(msg_hdr->msg_len, p);
1213 s2n(msg_hdr->seq, p);
1214 l2n3(msg_hdr->frag_off, p);
1215 l2n3(msg_hdr->frag_len, p);
1224 g_probable_mtu[(sizeof(g_probable_mtu) /
1225 sizeof(g_probable_mtu[0])) - 1];
1229 dtls1_guess_mtu(unsigned int curr_mtu)
1233 if ( curr_mtu == 0 )
1234 return g_probable_mtu[0] ;
1236 for ( i = 0; i < sizeof(g_probable_mtu)/sizeof(g_probable_mtu[0]); i++)
1237 if ( curr_mtu > g_probable_mtu[i])
1238 return g_probable_mtu[i];
1244 dtls1_get_message_header(unsigned char *data, struct hm_header_st *msg_hdr)
1246 memset(msg_hdr, 0x00, sizeof(struct hm_header_st));
1247 msg_hdr->type = *(data++);
1248 n2l3(data, msg_hdr->msg_len);
1250 n2s(data, msg_hdr->seq);
1251 n2l3(data, msg_hdr->frag_off);
1252 n2l3(data, msg_hdr->frag_len);
1256 dtls1_get_ccs_header(unsigned char *data, struct ccs_header_st *ccs_hdr)
1258 memset(ccs_hdr, 0x00, sizeof(struct ccs_header_st));
1260 ccs_hdr->type = *(data++);
1261 n2s(data, ccs_hdr->seq);