d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
freebsd-nq/crypto/openssl/ssl/d1_both.c
Simon L. B. Nielsen 6a599222bb Merge OpenSSL 0.9.8m into head. 
This also "reverts" some FreeBSD local changes so we should now
be back to using entirely stock OpenSSL.  The local changes were
simple $FreeBSD$ lines additions, which were required in the CVS
days, and the patch for FreeBSD-SA-09:15.ssl which has been
superseded with OpenSSL 0.9.8m's RFC5746 'TLS renegotiation
extension' support.

MFC after:	3 weeks
2010-03-13 19:22:41 +00:00

1271 lines
35 KiB
C
Raw Blame History

/* ssl/d1_both.c */
/*
* DTLS implementation written by Nagendra Modadugu
* (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
*/
/* ====================================================================
* Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <limits.h>
#include <string.h>
#include <stdio.h>
#include "ssl_locl.h"
#include <openssl/buffer.h>
#include <openssl/rand.h>
#include <openssl/objects.h>
#include <openssl/evp.h>
#include <openssl/x509.h>
/* XDTLS: figure out the right values */
static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28};
static unsigned int dtls1_min_mtu(void);
static unsigned int dtls1_guess_mtu(unsigned int curr_mtu);
static void dtls1_fix_message_header(SSL *s, unsigned long frag_off,
unsigned long frag_len);
static unsigned char *dtls1_write_message_header(SSL *s,
unsigned char *p);
static void dtls1_set_message_header_int(SSL *s, unsigned char mt,
unsigned long len, unsigned short seq_num, unsigned long frag_off,
unsigned long frag_len);
static long dtls1_get_message_fragment(SSL *s, int st1, int stn,
long max, int *ok);
static hm_fragment *
dtls1_hm_fragment_new(unsigned long frag_len)
{
hm_fragment *frag = NULL;
unsigned char *buf = NULL;
frag = (hm_fragment *)OPENSSL_malloc(sizeof(hm_fragment));
if ( frag == NULL)
return NULL;
if (frag_len)
{
buf = (unsigned char *)OPENSSL_malloc(frag_len);
if ( buf == NULL)
{
OPENSSL_free(frag);
return NULL;
}
}
/* zero length fragment gets zero frag->fragment */
frag->fragment = buf;
return frag;
}
static void
dtls1_hm_fragment_free(hm_fragment *frag)
{
if (frag->fragment) OPENSSL_free(frag->fragment);
OPENSSL_free(frag);
}
/* send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */
int dtls1_do_write(SSL *s, int type)
{
int ret;
int curr_mtu;
unsigned int len, frag_off, mac_size, blocksize;
/* AHA! Figure out the MTU, and stick to the right size */
if ( ! (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU))
{
s->d1->mtu =
BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
/* I've seen the kernel return bogus numbers when it doesn't know
* (initial write), so just make sure we have a reasonable number */
if ( s->d1->mtu < dtls1_min_mtu())
{
s->d1->mtu = 0;
s->d1->mtu = dtls1_guess_mtu(s->d1->mtu);
BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU,
s->d1->mtu, NULL);
}
}
#if 0
mtu = s->d1->mtu;
fprintf(stderr, "using MTU = %d\n", mtu);
mtu -= (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH);
curr_mtu = mtu - BIO_wpending(SSL_get_wbio(s));
if ( curr_mtu > 0)
mtu = curr_mtu;
else if ( ( ret = BIO_flush(SSL_get_wbio(s))) <= 0)
return ret;
if ( BIO_wpending(SSL_get_wbio(s)) + s->init_num >= mtu)
{
ret = BIO_flush(SSL_get_wbio(s));
if ( ret <= 0)
return ret;
mtu = s->d1->mtu - (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH);
}
OPENSSL_assert(mtu > 0); /* should have something reasonable now */
#endif
if ( s->init_off == 0 && type == SSL3_RT_HANDSHAKE)
OPENSSL_assert(s->init_num ==
(int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH);
if (s->write_hash)
mac_size = EVP_MD_size(s->write_hash);
else
mac_size = 0;
if (s->enc_write_ctx &&
(EVP_CIPHER_mode( s->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE))
blocksize = 2 * EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
else
blocksize = 0;
frag_off = 0;
while( s->init_num)
{
curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) -
DTLS1_RT_HEADER_LENGTH - mac_size - blocksize;
if ( curr_mtu <= DTLS1_HM_HEADER_LENGTH)
{
/* grr.. we could get an error if MTU picked was wrong */
ret = BIO_flush(SSL_get_wbio(s));
if ( ret <= 0)
return ret;
curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH -
mac_size - blocksize;
}
if ( s->init_num > curr_mtu)
len = curr_mtu;
else
len = s->init_num;
/* XDTLS: this function is too long. split out the CCS part */
if ( type == SSL3_RT_HANDSHAKE)
{
if ( s->init_off != 0)
{
OPENSSL_assert(s->init_off > DTLS1_HM_HEADER_LENGTH);
s->init_off -= DTLS1_HM_HEADER_LENGTH;
s->init_num += DTLS1_HM_HEADER_LENGTH;
/* write atleast DTLS1_HM_HEADER_LENGTH bytes */
if ( len <= DTLS1_HM_HEADER_LENGTH)
len += DTLS1_HM_HEADER_LENGTH;
}
dtls1_fix_message_header(s, frag_off,
len - DTLS1_HM_HEADER_LENGTH);
dtls1_write_message_header(s, (unsigned char *)&s->init_buf->data[s->init_off]);
OPENSSL_assert(len >= DTLS1_HM_HEADER_LENGTH);
}
ret=dtls1_write_bytes(s,type,&s->init_buf->data[s->init_off],
len);
if (ret < 0)
{
/* might need to update MTU here, but we don't know
* which previous packet caused the failure -- so can't
* really retransmit anything. continue as if everything
* is fine and wait for an alert to handle the
* retransmit
*/
if ( BIO_ctrl(SSL_get_wbio(s),
BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL) > 0 )
s->d1->mtu = BIO_ctrl(SSL_get_wbio(s),
BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
else
return(-1);
}
else
{
/* bad if this assert fails, only part of the handshake
* message got sent. but why would this happen? */
OPENSSL_assert(len == (unsigned int)ret);
if (type == SSL3_RT_HANDSHAKE && ! s->d1->retransmitting)
{
/* should not be done for 'Hello Request's, but in that case
* we'll ignore the result anyway */
unsigned char *p = (unsigned char *)&s->init_buf->data[s->init_off];
const struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr;
int xlen;
if (frag_off == 0 && s->client_version != DTLS1_BAD_VER)
{
/* reconstruct message header is if it
* is being sent in single fragment */
*p++ = msg_hdr->type;
l2n3(msg_hdr->msg_len,p);
s2n (msg_hdr->seq,p);
l2n3(0,p);
l2n3(msg_hdr->msg_len,p);
p -= DTLS1_HM_HEADER_LENGTH;
xlen = ret;
}
else
{
p += DTLS1_HM_HEADER_LENGTH;
xlen = ret - DTLS1_HM_HEADER_LENGTH;
}
ssl3_finish_mac(s, p, xlen);
}
if (ret == s->init_num)
{
if (s->msg_callback)
s->msg_callback(1, s->version, type, s->init_buf->data,
(size_t)(s->init_off + s->init_num), s,
s->msg_callback_arg);
s->init_off = 0; /* done writing this message */
s->init_num = 0;
return(1);
}
s->init_off+=ret;
s->init_num-=ret;
frag_off += (ret -= DTLS1_HM_HEADER_LENGTH);
}
}
return(0);
}
/* Obtain handshake message of message type 'mt' (any if mt == -1),
* maximum acceptable body length 'max'.
* Read an entire handshake message. Handshake messages arrive in
* fragments.
*/
long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok)
{
int i, al;
struct hm_header_st *msg_hdr;
/* s3->tmp is used to store messages that are unexpected, caused
* by the absence of an optional handshake message */
if (s->s3->tmp.reuse_message)
{
s->s3->tmp.reuse_message=0;
if ((mt >= 0) && (s->s3->tmp.message_type != mt))
{
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_DTLS1_GET_MESSAGE,SSL_R_UNEXPECTED_MESSAGE);
goto f_err;
}
*ok=1;
s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH;
s->init_num = (int)s->s3->tmp.message_size;
return s->init_num;
}
msg_hdr = &s->d1->r_msg_hdr;
do
{
if ( msg_hdr->frag_off == 0)
{
/* s->d1->r_message_header.msg_len = 0; */
memset(msg_hdr, 0x00, sizeof(struct hm_header_st));
}
i = dtls1_get_message_fragment(s, st1, stn, max, ok);
if ( i == DTLS1_HM_BAD_FRAGMENT ||
i == DTLS1_HM_FRAGMENT_RETRY) /* bad fragment received */
continue;
else if ( i <= 0 && !*ok)
return i;
/* Note that s->init_sum is used as a counter summing
* up fragments' lengths: as soon as they sum up to
* handshake packet length, we assume we have got all
* the fragments. Overlapping fragments would cause
* premature termination, so we don't expect overlaps.
* Well, handling overlaps would require something more
* drastic. Indeed, as it is now there is no way to
* tell if out-of-order fragment from the middle was
* the last. '>=' is the best/least we can do to control
* the potential damage caused by malformed overlaps. */
if ((unsigned int)s->init_num >= msg_hdr->msg_len)
{
unsigned char *p = (unsigned char *)s->init_buf->data;
unsigned long msg_len = msg_hdr->msg_len;
/* reconstruct message header as if it was
* sent in single fragment */
*(p++) = msg_hdr->type;
l2n3(msg_len,p);
s2n (msg_hdr->seq,p);
l2n3(0,p);
l2n3(msg_len,p);
if (s->client_version != DTLS1_BAD_VER)
p -= DTLS1_HM_HEADER_LENGTH,
msg_len += DTLS1_HM_HEADER_LENGTH;
ssl3_finish_mac(s, p, msg_len);
if (s->msg_callback)
s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
p, msg_len,
s, s->msg_callback_arg);
memset(msg_hdr, 0x00, sizeof(struct hm_header_st));
s->d1->handshake_read_seq++;
/* we just read a handshake message from the other side:
* this means that we don't need to retransmit of the
* buffered messages.
* XDTLS: may be able clear out this
* buffer a little sooner (i.e if an out-of-order
* handshake message/record is received at the record
* layer.
* XDTLS: exception is that the server needs to
* know that change cipher spec and finished messages
* have been received by the client before clearing this
* buffer. this can simply be done by waiting for the
* first data segment, but is there a better way? */
dtls1_clear_record_buffer(s);
s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH;
return s->init_num;
}
else
msg_hdr->frag_off = i;
} while(1) ;
f_err:
ssl3_send_alert(s,SSL3_AL_FATAL,al);
*ok = 0;
return -1;
}
static int dtls1_preprocess_fragment(SSL *s,struct hm_header_st *msg_hdr,int max)
{
size_t frag_off,frag_len,msg_len;
msg_len = msg_hdr->msg_len;
frag_off = msg_hdr->frag_off;
frag_len = msg_hdr->frag_len;
/* sanity checking */
if ( (frag_off+frag_len) > msg_len)
{
SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE);
return SSL_AD_ILLEGAL_PARAMETER;
}
if ( (frag_off+frag_len) > (unsigned long)max)
{
SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE);
return SSL_AD_ILLEGAL_PARAMETER;
}
if ( s->d1->r_msg_hdr.frag_off == 0) /* first fragment */
{
/* msg_len is limited to 2^24, but is effectively checked
* against max above */
if (!BUF_MEM_grow_clean(s->init_buf,(int)msg_len+DTLS1_HM_HEADER_LENGTH))
{
SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,ERR_R_BUF_LIB);
return SSL_AD_INTERNAL_ERROR;
}
s->s3->tmp.message_size = msg_len;
s->d1->r_msg_hdr.msg_len = msg_len;
s->s3->tmp.message_type = msg_hdr->type;
s->d1->r_msg_hdr.type = msg_hdr->type;
s->d1->r_msg_hdr.seq = msg_hdr->seq;
}
else if (msg_len != s->d1->r_msg_hdr.msg_len)
{
/* They must be playing with us! BTW, failure to enforce
* upper limit would open possibility for buffer overrun. */
SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,SSL_R_EXCESSIVE_MESSAGE_SIZE);
return SSL_AD_ILLEGAL_PARAMETER;
}
return 0; /* no error */
}
static int
dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok)
{
/* (0) check whether the desired fragment is available
* if so:
* (1) copy over the fragment to s->init_buf->data[]
* (2) update s->init_num
*/
pitem *item;
hm_fragment *frag;
int al;
*ok = 0;
item = pqueue_peek(s->d1->buffered_messages);
if ( item == NULL)
return 0;
frag = (hm_fragment *)item->data;
if ( s->d1->handshake_read_seq == frag->msg_header.seq)
{
unsigned long frag_len = frag->msg_header.frag_len;
pqueue_pop(s->d1->buffered_messages);
al=dtls1_preprocess_fragment(s,&frag->msg_header,max);
if (al==0) /* no alert */
{
unsigned char *p = (unsigned char *)s->init_buf->data+DTLS1_HM_HEADER_LENGTH;
memcpy(&p[frag->msg_header.frag_off],
frag->fragment,frag->msg_header.frag_len);
}
dtls1_hm_fragment_free(frag);
pitem_free(item);
if (al==0)
{
*ok = 1;
return frag_len;
}
ssl3_send_alert(s,SSL3_AL_FATAL,al);
s->init_num = 0;
*ok = 0;
return -1;
}
else
return 0;
}
static int
dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok)
{
int i=-1;
hm_fragment *frag = NULL;
pitem *item = NULL;
PQ_64BIT seq64;
unsigned long frag_len = msg_hdr->frag_len;
if ((msg_hdr->frag_off+frag_len) > msg_hdr->msg_len)
goto err;
/* Try to find item in queue, to prevent duplicate entries */
pq_64bit_init(&seq64);
pq_64bit_assign_word(&seq64, msg_hdr->seq);
item = pqueue_find(s->d1->buffered_messages, seq64);
pq_64bit_free(&seq64);
/* Discard the message if sequence number was already there, is
* too far in the future, already in the queue or if we received
* a FINISHED before the SERVER_HELLO, which then must be a stale
* retransmit.
*/
if (msg_hdr->seq <= s->d1->handshake_read_seq ||
msg_hdr->seq > s->d1->handshake_read_seq + 10 || item != NULL ||
(s->d1->handshake_read_seq == 0 && msg_hdr->type == SSL3_MT_FINISHED))
{
unsigned char devnull [256];
while (frag_len)
{
i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,
devnull,
frag_len>sizeof(devnull)?sizeof(devnull):frag_len,0);
if (i<=0) goto err;
frag_len -= i;
}
}
if (frag_len)
{
frag = dtls1_hm_fragment_new(frag_len);
if ( frag == NULL)
goto err;
memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr));
/* read the body of the fragment (header has already been read) */
i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,
frag->fragment,frag_len,0);
if (i<=0 || (unsigned long)i!=frag_len)
goto err;
pq_64bit_init(&seq64);
pq_64bit_assign_word(&seq64, msg_hdr->seq);
item = pitem_new(seq64, frag);
pq_64bit_free(&seq64);
if ( item == NULL)
goto err;
pqueue_insert(s->d1->buffered_messages, item);
}
return DTLS1_HM_FRAGMENT_RETRY;
err:
if ( frag != NULL) dtls1_hm_fragment_free(frag);
if ( item != NULL) OPENSSL_free(item);
*ok = 0;
return i;
}
static long
dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, int *ok)
{
unsigned char wire[DTLS1_HM_HEADER_LENGTH];
unsigned long l, frag_off, frag_len;
int i,al;
struct hm_header_st msg_hdr;
/* see if we have the required fragment already */
if ((frag_len = dtls1_retrieve_buffered_fragment(s,max,ok)) || *ok)
{
if (*ok) s->init_num += frag_len;
return frag_len;
}
/* read handshake message header */
i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,wire,
DTLS1_HM_HEADER_LENGTH, 0);
if (i <= 0) /* nbio, or an error */
{
s->rwstate=SSL_READING;
*ok = 0;
return i;
}
OPENSSL_assert(i == DTLS1_HM_HEADER_LENGTH);
/* parse the message fragment header */
dtls1_get_message_header(wire, &msg_hdr);
/*
* if this is a future (or stale) message it gets buffered
* (or dropped)--no further processing at this time
*/
if ( msg_hdr.seq != s->d1->handshake_read_seq)
return dtls1_process_out_of_seq_message(s, &msg_hdr, ok);
l = msg_hdr.msg_len;
frag_off = msg_hdr.frag_off;
frag_len = msg_hdr.frag_len;
if (!s->server && s->d1->r_msg_hdr.frag_off == 0 &&
wire[0] == SSL3_MT_HELLO_REQUEST)
{
/* The server may always send 'Hello Request' messages --
* we are doing a handshake anyway now, so ignore them
* if their format is correct. Does not count for
* 'Finished' MAC. */
if (wire[1] == 0 && wire[2] == 0 && wire[3] == 0)
{
if (s->msg_callback)
s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
wire, DTLS1_HM_HEADER_LENGTH, s,
s->msg_callback_arg);
s->init_num = 0;
return dtls1_get_message_fragment(s, st1, stn,
max, ok);
}
else /* Incorrectly formated Hello request */
{
al=SSL_AD_UNEXPECTED_MESSAGE;
SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT,SSL_R_UNEXPECTED_MESSAGE);
goto f_err;
}
}
if ((al=dtls1_preprocess_fragment(s,&msg_hdr,max)))
goto f_err;
/* XDTLS: ressurect this when restart is in place */
s->state=stn;
if ( frag_len > 0)
{
unsigned char *p=(unsigned char *)s->init_buf->data+DTLS1_HM_HEADER_LENGTH;
i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,
&p[frag_off],frag_len,0);
/* XDTLS: fix this--message fragments cannot span multiple packets */
if (i <= 0)
{
s->rwstate=SSL_READING;
*ok = 0;
return i;
}
}
else
i = 0;
/* XDTLS: an incorrectly formatted fragment should cause the
* handshake to fail */
OPENSSL_assert(i == (int)frag_len);
*ok = 1;
/* Note that s->init_num is *not* used as current offset in
* s->init_buf->data, but as a counter summing up fragments'
* lengths: as soon as they sum up to handshake packet
* length, we assume we have got all the fragments. */
s->init_num += frag_len;
return frag_len;
f_err:
ssl3_send_alert(s,SSL3_AL_FATAL,al);
s->init_num = 0;
*ok=0;
return(-1);
}
int dtls1_send_finished(SSL *s, int a, int b, const char *sender, int slen)
{
unsigned char *p,*d;
int i;
unsigned long l;
if (s->state == a)
{
d=(unsigned char *)s->init_buf->data;
p= &(d[DTLS1_HM_HEADER_LENGTH]);
i=s->method->ssl3_enc->final_finish_mac(s,
&(s->s3->finish_dgst1),
&(s->s3->finish_dgst2),
sender,slen,s->s3->tmp.finish_md);
s->s3->tmp.finish_md_len = i;
memcpy(p, s->s3->tmp.finish_md, i);
p+=i;
l=i;
/* Copy the finished so we can use it for
* renegotiation checks
*/
if(s->type == SSL_ST_CONNECT)
{
OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
memcpy(s->s3->previous_client_finished,
s->s3->tmp.finish_md, i);
s->s3->previous_client_finished_len=i;
}
else
{
OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
memcpy(s->s3->previous_server_finished,
s->s3->tmp.finish_md, i);
s->s3->previous_server_finished_len=i;
}
#ifdef OPENSSL_SYS_WIN16
/* MSVC 1.5 does not clear the top bytes of the word unless
* I do this.
*/
l&=0xffff;
#endif
d = dtls1_set_message_header(s, d, SSL3_MT_FINISHED, l, 0, l);
s->init_num=(int)l+DTLS1_HM_HEADER_LENGTH;
s->init_off=0;
/* buffer the message to handle re-xmits */
dtls1_buffer_message(s, 0);
s->state=b;
}
/* SSL3_ST_SEND_xxxxxx_HELLO_B */
return(dtls1_do_write(s,SSL3_RT_HANDSHAKE));
}
/* for these 2 messages, we need to
* ssl->enc_read_ctx re-init
* ssl->s3->read_sequence zero
* ssl->s3->read_mac_secret re-init
* ssl->session->read_sym_enc assign
* ssl->session->read_compression assign
* ssl->session->read_hash assign
*/
int dtls1_send_change_cipher_spec(SSL *s, int a, int b)
{
unsigned char *p;
if (s->state == a)
{
p=(unsigned char *)s->init_buf->data;
*p++=SSL3_MT_CCS;
s->d1->handshake_write_seq = s->d1->next_handshake_write_seq;
s->init_num=DTLS1_CCS_HEADER_LENGTH;
if (s->client_version == DTLS1_BAD_VER)
{
s->d1->next_handshake_write_seq++;
s2n(s->d1->handshake_write_seq,p);
s->init_num+=2;
}
s->init_off=0;
dtls1_set_message_header_int(s, SSL3_MT_CCS, 0,
s->d1->handshake_write_seq, 0, 0);
/* buffer the message to handle re-xmits */
dtls1_buffer_message(s, 1);
s->state=b;
}
/* SSL3_ST_CW_CHANGE_B */
return(dtls1_do_write(s,SSL3_RT_CHANGE_CIPHER_SPEC));
}
static int dtls1_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x)
{
int n;
unsigned char *p;
n=i2d_X509(x,NULL);
if (!BUF_MEM_grow_clean(buf,(int)(n+(*l)+3)))
{
SSLerr(SSL_F_DTLS1_ADD_CERT_TO_BUF,ERR_R_BUF_LIB);
return 0;
}
p=(unsigned char *)&(buf->data[*l]);
l2n3(n,p);
i2d_X509(x,&p);
*l+=n+3;
return 1;
}
unsigned long dtls1_output_cert_chain(SSL *s, X509 *x)
{
unsigned char *p;
int i;
unsigned long l= 3 + DTLS1_HM_HEADER_LENGTH;
BUF_MEM *buf;
/* TLSv1 sends a chain with nothing in it, instead of an alert */
buf=s->init_buf;
if (!BUF_MEM_grow_clean(buf,10))
{
SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB);
return(0);
}
if (x != NULL)
{
X509_STORE_CTX xs_ctx;
if (!X509_STORE_CTX_init(&xs_ctx,s->ctx->cert_store,x,NULL))
{
SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_X509_LIB);
return(0);
}
X509_verify_cert(&xs_ctx);
for (i=0; i < sk_X509_num(xs_ctx.chain); i++)
{
x = sk_X509_value(xs_ctx.chain, i);
if (!dtls1_add_cert_to_buf(buf, &l, x))
{
X509_STORE_CTX_cleanup(&xs_ctx);
return 0;
}
}
X509_STORE_CTX_cleanup(&xs_ctx);
}
/* Thawte special :-) */
for (i=0; i<sk_X509_num(s->ctx->extra_certs); i++)
{
x=sk_X509_value(s->ctx->extra_certs,i);
if (!dtls1_add_cert_to_buf(buf, &l, x))
return 0;
}
l-= (3 + DTLS1_HM_HEADER_LENGTH);
p=(unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]);
l2n3(l,p);
l+=3;
p=(unsigned char *)&(buf->data[0]);
p = dtls1_set_message_header(s, p, SSL3_MT_CERTIFICATE, l, 0, l);
l+=DTLS1_HM_HEADER_LENGTH;
return(l);
}
int dtls1_read_failed(SSL *s, int code)
{
if ( code > 0)
{
fprintf( stderr, "invalid state reached %s:%d", __FILE__, __LINE__);
return 1;
}
if (!dtls1_is_timer_expired(s))
{
/* not a timeout, none of our business,
let higher layers handle this. in fact it's probably an error */
return code;
}
if ( ! SSL_in_init(s)) /* done, no need to send a retransmit */
{
BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ);
return code;
}
#if 0 /* for now, each alert contains only one record number */
item = pqueue_peek(state->rcvd_records);
if ( item )
{
/* send an alert immediately for all the missing records */
}
else
#endif
#if 0 /* no more alert sending, just retransmit the last set of messages */
if ( state->timeout.read_timeouts >= DTLS1_TMO_READ_COUNT)
ssl3_send_alert(s,SSL3_AL_WARNING,
DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
#endif
return dtls1_handle_timeout(s);
}
int
dtls1_get_queue_priority(unsigned short seq, int is_ccs)
{
/* The index of the retransmission queue actually is the message sequence number,
* since the queue only contains messages of a single handshake. However, the
* ChangeCipherSpec has no message sequence number and so using only the sequence
* will result in the CCS and Finished having the same index. To prevent this,
* the sequence number is multiplied by 2. In case of a CCS 1 is subtracted.
* This does not only differ CSS and Finished, it also maintains the order of the
* index (important for priority queues) and fits in the unsigned short variable.
*/
return seq * 2 - is_ccs;
}
int
dtls1_retransmit_buffered_messages(SSL *s)
{
pqueue sent = s->d1->sent_messages;
piterator iter;
pitem *item;
hm_fragment *frag;
int found = 0;
iter = pqueue_iterator(sent);
for ( item = pqueue_next(&iter); item != NULL; item = pqueue_next(&iter))
{
frag = (hm_fragment *)item->data;
if ( dtls1_retransmit_message(s,
(unsigned short)dtls1_get_queue_priority(frag->msg_header.seq, frag->msg_header.is_ccs),
0, &found) <= 0 && found)
{
fprintf(stderr, "dtls1_retransmit_message() failed\n");
return -1;
}
}
return 1;
}
int
dtls1_buffer_message(SSL *s, int is_ccs)
{
pitem *item;
hm_fragment *frag;
PQ_64BIT seq64;
/* this function is called immediately after a message has
* been serialized */
OPENSSL_assert(s->init_off == 0);
frag = dtls1_hm_fragment_new(s->init_num);
memcpy(frag->fragment, s->init_buf->data, s->init_num);
if ( is_ccs)
{
OPENSSL_assert(s->d1->w_msg_hdr.msg_len +
DTLS1_CCS_HEADER_LENGTH <= (unsigned int)s->init_num);
}
else
{
OPENSSL_assert(s->d1->w_msg_hdr.msg_len +
DTLS1_HM_HEADER_LENGTH == (unsigned int)s->init_num);
}
frag->msg_header.msg_len = s->d1->w_msg_hdr.msg_len;
frag->msg_header.seq = s->d1->w_msg_hdr.seq;
frag->msg_header.type = s->d1->w_msg_hdr.type;
frag->msg_header.frag_off = 0;
frag->msg_header.frag_len = s->d1->w_msg_hdr.msg_len;
frag->msg_header.is_ccs = is_ccs;
/* save current state*/
frag->msg_header.saved_retransmit_state.enc_write_ctx = s->enc_write_ctx;
frag->msg_header.saved_retransmit_state.write_hash = s->write_hash;
frag->msg_header.saved_retransmit_state.compress = s->compress;
frag->msg_header.saved_retransmit_state.session = s->session;
frag->msg_header.saved_retransmit_state.epoch = s->d1->w_epoch;
pq_64bit_init(&seq64);
pq_64bit_assign_word(&seq64,
dtls1_get_queue_priority(frag->msg_header.seq,
frag->msg_header.is_ccs));
item = pitem_new(seq64, frag);
pq_64bit_free(&seq64);
if ( item == NULL)
{
dtls1_hm_fragment_free(frag);
return 0;
}
#if 0
fprintf( stderr, "buffered messge: \ttype = %xx\n", msg_buf->type);
fprintf( stderr, "\t\t\t\t\tlen = %d\n", msg_buf->len);
fprintf( stderr, "\t\t\t\t\tseq_num = %d\n", msg_buf->seq_num);
#endif
pqueue_insert(s->d1->sent_messages, item);
return 1;
}
int
dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off,
int *found)
{
int ret;
/* XDTLS: for now assuming that read/writes are blocking */
pitem *item;
hm_fragment *frag ;
unsigned long header_length;
PQ_64BIT seq64;
struct dtls1_retransmit_state saved_state;
unsigned char save_write_sequence[8];
/*
OPENSSL_assert(s->init_num == 0);
OPENSSL_assert(s->init_off == 0);
*/
/* XDTLS: the requested message ought to be found, otherwise error */
pq_64bit_init(&seq64);
pq_64bit_assign_word(&seq64, seq);
item = pqueue_find(s->d1->sent_messages, seq64);
pq_64bit_free(&seq64);
if ( item == NULL)
{
fprintf(stderr, "retransmit: message %d non-existant\n", seq);
*found = 0;
return 0;
}
*found = 1;
frag = (hm_fragment *)item->data;
if ( frag->msg_header.is_ccs)
header_length = DTLS1_CCS_HEADER_LENGTH;
else
header_length = DTLS1_HM_HEADER_LENGTH;
memcpy(s->init_buf->data, frag->fragment,
frag->msg_header.msg_len + header_length);
s->init_num = frag->msg_header.msg_len + header_length;
dtls1_set_message_header_int(s, frag->msg_header.type,
frag->msg_header.msg_len, frag->msg_header.seq, 0,
frag->msg_header.frag_len);
/* save current state */
saved_state.enc_write_ctx = s->enc_write_ctx;
saved_state.write_hash = s->write_hash;
saved_state.compress = s->compress;
saved_state.session = s->session;
saved_state.epoch = s->d1->w_epoch;
saved_state.epoch = s->d1->w_epoch;
s->d1->retransmitting = 1;
/* restore state in which the message was originally sent */
s->enc_write_ctx = frag->msg_header.saved_retransmit_state.enc_write_ctx;
s->write_hash = frag->msg_header.saved_retransmit_state.write_hash;
s->compress = frag->msg_header.saved_retransmit_state.compress;
s->session = frag->msg_header.saved_retransmit_state.session;
s->d1->w_epoch = frag->msg_header.saved_retransmit_state.epoch;
if (frag->msg_header.saved_retransmit_state.epoch == saved_state.epoch - 1)
{
memcpy(save_write_sequence, s->s3->write_sequence, sizeof(s->s3->write_sequence));
memcpy(s->s3->write_sequence, s->d1->last_write_sequence, sizeof(s->s3->write_sequence));
}
ret = dtls1_do_write(s, frag->msg_header.is_ccs ?
SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE);
/* restore current state */
s->enc_write_ctx = saved_state.enc_write_ctx;
s->write_hash = saved_state.write_hash;
s->compress = saved_state.compress;
s->session = saved_state.session;
s->d1->w_epoch = saved_state.epoch;
if (frag->msg_header.saved_retransmit_state.epoch == saved_state.epoch - 1)
{
memcpy(s->d1->last_write_sequence, s->s3->write_sequence, sizeof(s->s3->write_sequence));
memcpy(s->s3->write_sequence, save_write_sequence, sizeof(s->s3->write_sequence));
}
s->d1->retransmitting = 0;
(void)BIO_flush(SSL_get_wbio(s));
return ret;
}
/* call this function when the buffered messages are no longer needed */
void
dtls1_clear_record_buffer(SSL *s)
{
pitem *item;
for(item = pqueue_pop(s->d1->sent_messages);
item != NULL; item = pqueue_pop(s->d1->sent_messages))
{
dtls1_hm_fragment_free((hm_fragment *)item->data);
pitem_free(item);
}
}
unsigned char *
dtls1_set_message_header(SSL *s, unsigned char *p, unsigned char mt,
unsigned long len, unsigned long frag_off, unsigned long frag_len)
{
if ( frag_off == 0)
{
s->d1->handshake_write_seq = s->d1->next_handshake_write_seq;
s->d1->next_handshake_write_seq++;
}
dtls1_set_message_header_int(s, mt, len, s->d1->handshake_write_seq,
frag_off, frag_len);
return p += DTLS1_HM_HEADER_LENGTH;
}
/* don't actually do the writing, wait till the MTU has been retrieved */
static void
dtls1_set_message_header_int(SSL *s, unsigned char mt,
unsigned long len, unsigned short seq_num, unsigned long frag_off,
unsigned long frag_len)
{
struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr;
msg_hdr->type = mt;
msg_hdr->msg_len = len;
msg_hdr->seq = seq_num;
msg_hdr->frag_off = frag_off;
msg_hdr->frag_len = frag_len;
}
static void
dtls1_fix_message_header(SSL *s, unsigned long frag_off,
unsigned long frag_len)
{
struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr;
msg_hdr->frag_off = frag_off;
msg_hdr->frag_len = frag_len;
}
static unsigned char *
dtls1_write_message_header(SSL *s, unsigned char *p)
{
struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr;
*p++ = msg_hdr->type;
l2n3(msg_hdr->msg_len, p);
s2n(msg_hdr->seq, p);
l2n3(msg_hdr->frag_off, p);
l2n3(msg_hdr->frag_len, p);
return p;
}
static unsigned int
dtls1_min_mtu(void)
{
return (g_probable_mtu[(sizeof(g_probable_mtu) /
sizeof(g_probable_mtu[0])) - 1]);
}
static unsigned int
dtls1_guess_mtu(unsigned int curr_mtu)
{
size_t i;
if ( curr_mtu == 0 )
return g_probable_mtu[0] ;
for ( i = 0; i < sizeof(g_probable_mtu)/sizeof(g_probable_mtu[0]); i++)
if ( curr_mtu > g_probable_mtu[i])
return g_probable_mtu[i];
return curr_mtu;
}
void
dtls1_get_message_header(unsigned char *data, struct hm_header_st *msg_hdr)
{
memset(msg_hdr, 0x00, sizeof(struct hm_header_st));
msg_hdr->type = *(data++);
n2l3(data, msg_hdr->msg_len);
n2s(data, msg_hdr->seq);
n2l3(data, msg_hdr->frag_off);
n2l3(data, msg_hdr->frag_len);
}
void
dtls1_get_ccs_header(unsigned char *data, struct ccs_header_st *ccs_hdr)
{
memset(ccs_hdr, 0x00, sizeof(struct ccs_header_st));
ccs_hdr->type = *(data++);
}
Reference in New Issue View Git Blame Copy Permalink