ec847cea9b
It has size 7. There's no need for a priority queue structure, especially one that's O(N^2) anyway. Change-Id: I7609794aac1925c9bbf3015744cae266dcb79bff Reviewed-on: https://boringssl-review.googlesource.com/8437 Reviewed-by: Adam Langley <agl@google.com>
780 lines
26 KiB
C
780 lines
26 KiB
C
/*
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* DTLS implementation written by Nagendra Modadugu
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* (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
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*/
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/* ====================================================================
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* Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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*
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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*
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* 3. All advertising materials mentioning features or use of this
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* software must display the following acknowledgment:
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* "This product includes software developed by the OpenSSL Project
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* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
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*
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* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
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* endorse or promote products derived from this software without
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* prior written permission. For written permission, please contact
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* openssl-core@openssl.org.
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*
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* 5. Products derived from this software may not be called "OpenSSL"
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* nor may "OpenSSL" appear in their names without prior written
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* permission of the OpenSSL Project.
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*
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* 6. Redistributions of any form whatsoever must retain the following
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* acknowledgment:
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* "This product includes software developed by the OpenSSL Project
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* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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*
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* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
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* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
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* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
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* OF THE POSSIBILITY OF SUCH DAMAGE.
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* ====================================================================
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*
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* This product includes cryptographic software written by Eric Young
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* (eay@cryptsoft.com). This product includes software written by Tim
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* Hudson (tjh@cryptsoft.com).
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*
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*/
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/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
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* All rights reserved.
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*
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* This package is an SSL implementation written
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* by Eric Young (eay@cryptsoft.com).
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* The implementation was written so as to conform with Netscapes SSL.
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*
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* This library is free for commercial and non-commercial use as long as
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* the following conditions are aheared to. The following conditions
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* apply to all code found in this distribution, be it the RC4, RSA,
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* lhash, DES, etc., code; not just the SSL code. The SSL documentation
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* included with this distribution is covered by the same copyright terms
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* except that the holder is Tim Hudson (tjh@cryptsoft.com).
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*
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* Copyright remains Eric Young's, and as such any Copyright notices in
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* the code are not to be removed.
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* If this package is used in a product, Eric Young should be given attribution
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* as the author of the parts of the library used.
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* This can be in the form of a textual message at program startup or
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* in documentation (online or textual) provided with the package.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* "This product includes cryptographic software written by
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* Eric Young (eay@cryptsoft.com)"
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* The word 'cryptographic' can be left out if the rouines from the library
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* being used are not cryptographic related :-).
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* 4. If you include any Windows specific code (or a derivative thereof) from
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* the apps directory (application code) you must include an acknowledgement:
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* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
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*
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* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* The licence and distribution terms for any publically available version or
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* derivative of this code cannot be changed. i.e. this code cannot simply be
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* copied and put under another distribution licence
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* [including the GNU Public Licence.] */
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#include <openssl/ssl.h>
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#include <assert.h>
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#include <limits.h>
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#include <string.h>
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#include <openssl/buf.h>
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#include <openssl/err.h>
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#include <openssl/evp.h>
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#include <openssl/mem.h>
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#include <openssl/rand.h>
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#include <openssl/x509.h>
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#include "internal.h"
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/* TODO(davidben): 28 comes from the size of IP + UDP header. Is this reasonable
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* for these values? Notably, why is kMinMTU a function of the transport
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* protocol's overhead rather than, say, what's needed to hold a minimally-sized
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* handshake fragment plus protocol overhead. */
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/* kMinMTU is the minimum acceptable MTU value. */
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static const unsigned int kMinMTU = 256 - 28;
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/* kDefaultMTU is the default MTU value to use if neither the user nor
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* the underlying BIO supplies one. */
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static const unsigned int kDefaultMTU = 1500 - 28;
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static void dtls1_hm_fragment_free(hm_fragment *frag) {
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if (frag == NULL) {
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return;
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}
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OPENSSL_free(frag->fragment);
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OPENSSL_free(frag->reassembly);
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OPENSSL_free(frag);
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}
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static hm_fragment *dtls1_hm_fragment_new(size_t frag_len) {
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hm_fragment *frag = OPENSSL_malloc(sizeof(hm_fragment));
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if (frag == NULL) {
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OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
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return NULL;
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}
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memset(frag, 0, sizeof(hm_fragment));
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/* If the handshake message is empty, |frag->fragment| and |frag->reassembly|
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* are NULL. */
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if (frag_len > 0) {
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frag->fragment = OPENSSL_malloc(frag_len);
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if (frag->fragment == NULL) {
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OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
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goto err;
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}
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/* Initialize reassembly bitmask. */
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if (frag_len + 7 < frag_len) {
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OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
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goto err;
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}
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size_t bitmask_len = (frag_len + 7) / 8;
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frag->reassembly = OPENSSL_malloc(bitmask_len);
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if (frag->reassembly == NULL) {
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OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
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goto err;
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}
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memset(frag->reassembly, 0, bitmask_len);
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}
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return frag;
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err:
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dtls1_hm_fragment_free(frag);
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return NULL;
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}
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#if !defined(inline)
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#define inline __inline
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#endif
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/* bit_range returns a |uint8_t| with bits |start|, inclusive, to |end|,
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* exclusive, set. */
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static inline uint8_t bit_range(size_t start, size_t end) {
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return (uint8_t)(~((1u << start) - 1) & ((1u << end) - 1));
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}
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/* dtls1_hm_fragment_mark marks bytes |start|, inclusive, to |end|, exclusive,
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* as received in |frag|. If |frag| becomes complete, it clears
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* |frag->reassembly|. The range must be within the bounds of |frag|'s message
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* and |frag->reassembly| must not be NULL. */
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static void dtls1_hm_fragment_mark(hm_fragment *frag, size_t start,
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size_t end) {
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size_t i;
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size_t msg_len = frag->msg_header.msg_len;
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if (frag->reassembly == NULL || start > end || end > msg_len) {
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assert(0);
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return;
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}
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/* A zero-length message will never have a pending reassembly. */
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assert(msg_len > 0);
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if ((start >> 3) == (end >> 3)) {
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frag->reassembly[start >> 3] |= bit_range(start & 7, end & 7);
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} else {
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frag->reassembly[start >> 3] |= bit_range(start & 7, 8);
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for (i = (start >> 3) + 1; i < (end >> 3); i++) {
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frag->reassembly[i] = 0xff;
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}
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if ((end & 7) != 0) {
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frag->reassembly[end >> 3] |= bit_range(0, end & 7);
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}
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}
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/* Check if the fragment is complete. */
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for (i = 0; i < (msg_len >> 3); i++) {
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if (frag->reassembly[i] != 0xff) {
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return;
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}
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}
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if ((msg_len & 7) != 0 &&
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frag->reassembly[msg_len >> 3] != bit_range(0, msg_len & 7)) {
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return;
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}
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OPENSSL_free(frag->reassembly);
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frag->reassembly = NULL;
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}
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static void dtls1_update_mtu(SSL *ssl) {
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/* TODO(davidben): What is this code doing and do we need it? */
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if (ssl->d1->mtu < dtls1_min_mtu() &&
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!(SSL_get_options(ssl) & SSL_OP_NO_QUERY_MTU)) {
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long mtu = BIO_ctrl(ssl->wbio, BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
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if (mtu >= 0 && mtu <= (1 << 30) && (unsigned)mtu >= dtls1_min_mtu()) {
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ssl->d1->mtu = (unsigned)mtu;
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} else {
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ssl->d1->mtu = kDefaultMTU;
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BIO_ctrl(ssl->wbio, BIO_CTRL_DGRAM_SET_MTU, ssl->d1->mtu, NULL);
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}
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}
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/* The MTU should be above the minimum now. */
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assert(ssl->d1->mtu >= dtls1_min_mtu());
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}
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/* dtls1_max_record_size returns the maximum record body length that may be
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* written without exceeding the MTU. It accounts for any buffering installed on
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* the write BIO. If no record may be written, it returns zero. */
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static size_t dtls1_max_record_size(SSL *ssl) {
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size_t ret = ssl->d1->mtu;
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size_t overhead = ssl_max_seal_overhead(ssl);
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if (ret <= overhead) {
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return 0;
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}
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ret -= overhead;
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size_t pending = BIO_wpending(ssl->wbio);
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if (ret <= pending) {
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return 0;
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}
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ret -= pending;
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return ret;
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}
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static int dtls1_write_change_cipher_spec(SSL *ssl,
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enum dtls1_use_epoch_t use_epoch) {
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dtls1_update_mtu(ssl);
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/* During the handshake, wbio is buffered to pack messages together. Flush the
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* buffer if the ChangeCipherSpec would not fit in a packet. */
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if (dtls1_max_record_size(ssl) == 0) {
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int ret = BIO_flush(ssl->wbio);
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if (ret <= 0) {
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ssl->rwstate = SSL_WRITING;
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return ret;
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}
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}
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static const uint8_t kChangeCipherSpec[1] = {SSL3_MT_CCS};
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int ret =
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dtls1_write_record(ssl, SSL3_RT_CHANGE_CIPHER_SPEC, kChangeCipherSpec,
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sizeof(kChangeCipherSpec), use_epoch);
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if (ret <= 0) {
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return ret;
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}
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ssl_do_msg_callback(ssl, 1 /* write */, ssl->version,
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SSL3_RT_CHANGE_CIPHER_SPEC, kChangeCipherSpec,
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sizeof(kChangeCipherSpec));
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return 1;
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}
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int dtls1_do_handshake_write(SSL *ssl, size_t *out_offset, const uint8_t *in,
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size_t offset, size_t len,
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enum dtls1_use_epoch_t use_epoch) {
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dtls1_update_mtu(ssl);
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int ret = -1;
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CBB cbb;
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CBB_zero(&cbb);
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/* Allocate a temporary buffer to hold the message fragments to avoid
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* clobbering the message. */
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uint8_t *buf = OPENSSL_malloc(ssl->d1->mtu);
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if (buf == NULL) {
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goto err;
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}
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/* Although it may be sent as multiple fragments, a DTLS message must be sent
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* serialized as a single fragment for purposes of |ssl_do_msg_callback| and
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* the handshake hash. */
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CBS cbs, body;
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struct hm_header_st hdr;
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CBS_init(&cbs, in, len);
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if (!dtls1_parse_fragment(&cbs, &hdr, &body) ||
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hdr.frag_off != 0 ||
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hdr.frag_len != CBS_len(&body) ||
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hdr.msg_len != CBS_len(&body) ||
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!CBS_skip(&body, offset) ||
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CBS_len(&cbs) != 0) {
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OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
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goto err;
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}
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do {
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/* During the handshake, wbio is buffered to pack messages together. Flush
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* the buffer if there isn't enough room to make progress. */
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if (dtls1_max_record_size(ssl) < DTLS1_HM_HEADER_LENGTH + 1) {
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int flush_ret = BIO_flush(ssl->wbio);
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if (flush_ret <= 0) {
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ssl->rwstate = SSL_WRITING;
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ret = flush_ret;
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goto err;
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}
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assert(BIO_wpending(ssl->wbio) == 0);
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}
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size_t todo = dtls1_max_record_size(ssl);
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if (todo < DTLS1_HM_HEADER_LENGTH + 1) {
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/* To make forward progress, the MTU must, at minimum, fit the handshake
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* header and one byte of handshake body. */
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OPENSSL_PUT_ERROR(SSL, SSL_R_MTU_TOO_SMALL);
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goto err;
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}
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todo -= DTLS1_HM_HEADER_LENGTH;
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if (todo > CBS_len(&body)) {
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todo = CBS_len(&body);
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}
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if (todo >= (1u << 24)) {
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todo = (1u << 24) - 1;
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}
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size_t buf_len;
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if (!CBB_init_fixed(&cbb, buf, ssl->d1->mtu) ||
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!CBB_add_u8(&cbb, hdr.type) ||
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!CBB_add_u24(&cbb, hdr.msg_len) ||
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!CBB_add_u16(&cbb, hdr.seq) ||
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!CBB_add_u24(&cbb, offset) ||
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!CBB_add_u24(&cbb, todo) ||
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!CBB_add_bytes(&cbb, CBS_data(&body), todo) ||
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!CBB_finish(&cbb, NULL, &buf_len)) {
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OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
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goto err;
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}
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int write_ret =
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dtls1_write_record(ssl, SSL3_RT_HANDSHAKE, buf, buf_len, use_epoch);
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if (write_ret <= 0) {
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ret = write_ret;
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goto err;
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}
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if (!CBS_skip(&body, todo)) {
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OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
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goto err;
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}
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offset += todo;
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} while (CBS_len(&body) != 0);
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ssl_do_msg_callback(ssl, 1 /* write */, ssl->version, SSL3_RT_HANDSHAKE, in,
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len);
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ret = 1;
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err:
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*out_offset = offset;
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CBB_cleanup(&cbb);
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OPENSSL_free(buf);
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return ret;
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}
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/* dtls1_is_next_message_complete returns one if the next handshake message is
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* complete and zero otherwise. */
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static int dtls1_is_next_message_complete(SSL *ssl) {
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hm_fragment *frag = ssl->d1->incoming_messages[ssl->d1->handshake_read_seq %
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SSL_MAX_HANDSHAKE_FLIGHT];
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return frag != NULL && frag->reassembly == NULL;
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}
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/* dtls1_get_buffered_message returns the buffered message corresponding to
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* |msg_hdr|. If none exists, it creates a new one and inserts it in the
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* queue. Otherwise, it checks |msg_hdr| is consistent with the existing one. It
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* returns NULL on failure. The caller does not take ownership of the result. */
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static hm_fragment *dtls1_get_buffered_message(
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SSL *ssl, const struct hm_header_st *msg_hdr) {
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if (msg_hdr->seq < ssl->d1->handshake_read_seq ||
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msg_hdr->seq - ssl->d1->handshake_read_seq >= SSL_MAX_HANDSHAKE_FLIGHT) {
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return NULL;
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}
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size_t idx = msg_hdr->seq % SSL_MAX_HANDSHAKE_FLIGHT;
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hm_fragment *frag = ssl->d1->incoming_messages[idx];
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if (frag != NULL) {
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assert(frag->msg_header.seq == msg_hdr->seq);
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/* The new fragment must be compatible with the previous fragments from this
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* message. */
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if (frag->msg_header.type != msg_hdr->type ||
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frag->msg_header.msg_len != msg_hdr->msg_len) {
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OPENSSL_PUT_ERROR(SSL, SSL_R_FRAGMENT_MISMATCH);
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ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
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return NULL;
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}
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return frag;
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}
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/* This is the first fragment from this message. */
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frag = dtls1_hm_fragment_new(msg_hdr->msg_len);
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if (frag == NULL) {
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return NULL;
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}
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memcpy(&frag->msg_header, msg_hdr, sizeof(*msg_hdr));
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ssl->d1->incoming_messages[idx] = frag;
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return frag;
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}
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/* dtls1_process_handshake_record reads a handshake record and processes it. It
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* returns one if the record was successfully processed and 0 or -1 on error. */
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static int dtls1_process_handshake_record(SSL *ssl) {
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SSL3_RECORD *rr = &ssl->s3->rrec;
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start:
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if (rr->length == 0) {
|
|
int ret = dtls1_get_record(ssl);
|
|
if (ret <= 0) {
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* Cross-epoch records are discarded, but we may receive out-of-order
|
|
* application data between ChangeCipherSpec and Finished or a ChangeCipherSpec
|
|
* before the appropriate point in the handshake. Those must be silently
|
|
* discarded.
|
|
*
|
|
* However, only allow the out-of-order records in the correct epoch.
|
|
* Application data must come in the encrypted epoch, and ChangeCipherSpec in
|
|
* the unencrypted epoch (we never renegotiate). Other cases fall through and
|
|
* fail with a fatal error. */
|
|
if ((rr->type == SSL3_RT_APPLICATION_DATA &&
|
|
ssl->s3->aead_read_ctx != NULL) ||
|
|
(rr->type == SSL3_RT_CHANGE_CIPHER_SPEC &&
|
|
ssl->s3->aead_read_ctx == NULL)) {
|
|
rr->length = 0;
|
|
goto start;
|
|
}
|
|
|
|
if (rr->type != SSL3_RT_HANDSHAKE) {
|
|
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
|
|
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_RECORD);
|
|
return -1;
|
|
}
|
|
|
|
CBS cbs;
|
|
CBS_init(&cbs, rr->data, rr->length);
|
|
|
|
while (CBS_len(&cbs) > 0) {
|
|
/* Read a handshake fragment. */
|
|
struct hm_header_st msg_hdr;
|
|
CBS body;
|
|
if (!dtls1_parse_fragment(&cbs, &msg_hdr, &body)) {
|
|
OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_HANDSHAKE_RECORD);
|
|
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
|
|
return -1;
|
|
}
|
|
|
|
const size_t frag_off = msg_hdr.frag_off;
|
|
const size_t frag_len = msg_hdr.frag_len;
|
|
const size_t msg_len = msg_hdr.msg_len;
|
|
if (frag_off > msg_len || frag_off + frag_len < frag_off ||
|
|
frag_off + frag_len > msg_len ||
|
|
msg_len > ssl_max_handshake_message_len(ssl)) {
|
|
OPENSSL_PUT_ERROR(SSL, SSL_R_EXCESSIVE_MESSAGE_SIZE);
|
|
ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
|
|
return -1;
|
|
}
|
|
|
|
if (msg_hdr.seq < ssl->d1->handshake_read_seq ||
|
|
msg_hdr.seq >
|
|
(unsigned)ssl->d1->handshake_read_seq + SSL_MAX_HANDSHAKE_FLIGHT) {
|
|
/* Ignore fragments from the past, or ones too far in the future. */
|
|
continue;
|
|
}
|
|
|
|
hm_fragment *frag = dtls1_get_buffered_message(ssl, &msg_hdr);
|
|
if (frag == NULL) {
|
|
return -1;
|
|
}
|
|
assert(frag->msg_header.msg_len == msg_len);
|
|
|
|
if (frag->reassembly == NULL) {
|
|
/* The message is already assembled. */
|
|
continue;
|
|
}
|
|
assert(msg_len > 0);
|
|
|
|
/* Copy the body into the fragment. */
|
|
memcpy(frag->fragment + frag_off, CBS_data(&body), CBS_len(&body));
|
|
dtls1_hm_fragment_mark(frag, frag_off, frag_off + frag_len);
|
|
}
|
|
|
|
rr->length = 0;
|
|
ssl_read_buffer_discard(ssl);
|
|
return 1;
|
|
}
|
|
|
|
/* dtls1_get_message reads a handshake message of message type |msg_type| (any
|
|
* if |msg_type| == -1). Read an entire handshake message. Handshake messages
|
|
* arrive in fragments. */
|
|
long dtls1_get_message(SSL *ssl, int msg_type,
|
|
enum ssl_hash_message_t hash_message, int *ok) {
|
|
hm_fragment *frag = NULL;
|
|
int al;
|
|
|
|
/* s3->tmp is used to store messages that are unexpected, caused
|
|
* by the absence of an optional handshake message */
|
|
if (ssl->s3->tmp.reuse_message) {
|
|
/* A ssl_dont_hash_message call cannot be combined with reuse_message; the
|
|
* ssl_dont_hash_message would have to have been applied to the previous
|
|
* call. */
|
|
assert(hash_message == ssl_hash_message);
|
|
ssl->s3->tmp.reuse_message = 0;
|
|
if (msg_type >= 0 && ssl->s3->tmp.message_type != msg_type) {
|
|
al = SSL_AD_UNEXPECTED_MESSAGE;
|
|
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
|
|
goto f_err;
|
|
}
|
|
*ok = 1;
|
|
assert(ssl->init_buf->length >= DTLS1_HM_HEADER_LENGTH);
|
|
ssl->init_msg = (uint8_t *)ssl->init_buf->data + DTLS1_HM_HEADER_LENGTH;
|
|
ssl->init_num = (int)ssl->init_buf->length - DTLS1_HM_HEADER_LENGTH;
|
|
return ssl->init_num;
|
|
}
|
|
|
|
/* Process handshake records until the next message is ready. */
|
|
while (!dtls1_is_next_message_complete(ssl)) {
|
|
int ret = dtls1_process_handshake_record(ssl);
|
|
if (ret <= 0) {
|
|
*ok = 0;
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* Pop an entry from the ring buffer. */
|
|
frag = ssl->d1->incoming_messages[ssl->d1->handshake_read_seq %
|
|
SSL_MAX_HANDSHAKE_FLIGHT];
|
|
ssl->d1->incoming_messages[ssl->d1->handshake_read_seq %
|
|
SSL_MAX_HANDSHAKE_FLIGHT] = NULL;
|
|
|
|
assert(frag != NULL);
|
|
assert(frag->reassembly == NULL);
|
|
assert(ssl->d1->handshake_read_seq == frag->msg_header.seq);
|
|
|
|
ssl->d1->handshake_read_seq++;
|
|
|
|
/* Reconstruct the assembled message. */
|
|
CBB cbb;
|
|
CBB_zero(&cbb);
|
|
if (!BUF_MEM_reserve(ssl->init_buf, (size_t)frag->msg_header.msg_len +
|
|
DTLS1_HM_HEADER_LENGTH) ||
|
|
!CBB_init_fixed(&cbb, (uint8_t *)ssl->init_buf->data,
|
|
ssl->init_buf->max) ||
|
|
!CBB_add_u8(&cbb, frag->msg_header.type) ||
|
|
!CBB_add_u24(&cbb, frag->msg_header.msg_len) ||
|
|
!CBB_add_u16(&cbb, frag->msg_header.seq) ||
|
|
!CBB_add_u24(&cbb, 0 /* frag_off */) ||
|
|
!CBB_add_u24(&cbb, frag->msg_header.msg_len) ||
|
|
!CBB_add_bytes(&cbb, frag->fragment, frag->msg_header.msg_len) ||
|
|
!CBB_finish(&cbb, NULL, &ssl->init_buf->length)) {
|
|
CBB_cleanup(&cbb);
|
|
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
|
|
goto err;
|
|
}
|
|
assert(ssl->init_buf->length ==
|
|
(size_t)frag->msg_header.msg_len + DTLS1_HM_HEADER_LENGTH);
|
|
|
|
/* TODO(davidben): This function has a lot of implicit outputs. Simplify the
|
|
* |ssl_get_message| API. */
|
|
ssl->s3->tmp.message_type = frag->msg_header.type;
|
|
ssl->init_msg = (uint8_t *)ssl->init_buf->data + DTLS1_HM_HEADER_LENGTH;
|
|
ssl->init_num = frag->msg_header.msg_len;
|
|
|
|
if (msg_type >= 0 && ssl->s3->tmp.message_type != msg_type) {
|
|
al = SSL_AD_UNEXPECTED_MESSAGE;
|
|
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
|
|
goto f_err;
|
|
}
|
|
if (hash_message == ssl_hash_message && !ssl3_hash_current_message(ssl)) {
|
|
goto err;
|
|
}
|
|
|
|
ssl_do_msg_callback(ssl, 0 /* read */, ssl->version, SSL3_RT_HANDSHAKE,
|
|
ssl->init_buf->data,
|
|
ssl->init_num + DTLS1_HM_HEADER_LENGTH);
|
|
|
|
dtls1_hm_fragment_free(frag);
|
|
|
|
*ok = 1;
|
|
return ssl->init_num;
|
|
|
|
f_err:
|
|
ssl3_send_alert(ssl, SSL3_AL_FATAL, al);
|
|
err:
|
|
dtls1_hm_fragment_free(frag);
|
|
*ok = 0;
|
|
return -1;
|
|
}
|
|
|
|
static int dtls1_retransmit_message(SSL *ssl,
|
|
const DTLS_OUTGOING_MESSAGE *msg) {
|
|
/* DTLS renegotiation is unsupported, so only epochs 0 (NULL cipher) and 1
|
|
* (negotiated cipher) exist. */
|
|
assert(ssl->d1->w_epoch == 0 || ssl->d1->w_epoch == 1);
|
|
assert(msg->epoch <= ssl->d1->w_epoch);
|
|
enum dtls1_use_epoch_t use_epoch = dtls1_use_current_epoch;
|
|
if (ssl->d1->w_epoch == 1 && msg->epoch == 0) {
|
|
use_epoch = dtls1_use_previous_epoch;
|
|
}
|
|
|
|
/* TODO(davidben): This cannot handle non-blocking writes. */
|
|
int ret;
|
|
if (msg->is_ccs) {
|
|
ret = dtls1_write_change_cipher_spec(ssl, use_epoch);
|
|
} else {
|
|
size_t offset = 0;
|
|
ret = dtls1_do_handshake_write(ssl, &offset, msg->data, offset, msg->len,
|
|
use_epoch);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
int dtls1_retransmit_buffered_messages(SSL *ssl) {
|
|
/* Ensure we are packing handshake messages. */
|
|
const int was_buffered = ssl_is_wbio_buffered(ssl);
|
|
assert(was_buffered == SSL_in_init(ssl));
|
|
if (!was_buffered && !ssl_init_wbio_buffer(ssl)) {
|
|
return -1;
|
|
}
|
|
assert(ssl_is_wbio_buffered(ssl));
|
|
|
|
int ret = -1;
|
|
size_t i;
|
|
for (i = 0; i < ssl->d1->outgoing_messages_len; i++) {
|
|
if (dtls1_retransmit_message(ssl, &ssl->d1->outgoing_messages[i]) <= 0) {
|
|
goto err;
|
|
}
|
|
}
|
|
|
|
ret = BIO_flush(ssl->wbio);
|
|
if (ret <= 0) {
|
|
ssl->rwstate = SSL_WRITING;
|
|
goto err;
|
|
}
|
|
|
|
err:
|
|
if (!was_buffered) {
|
|
ssl_free_wbio_buffer(ssl);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/* dtls1_buffer_change_cipher_spec adds a ChangeCipherSpec to the current
|
|
* handshake flight. */
|
|
static int dtls1_buffer_change_cipher_spec(SSL *ssl) {
|
|
if (ssl->d1->outgoing_messages_len >= SSL_MAX_HANDSHAKE_FLIGHT) {
|
|
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
|
|
return 0;
|
|
}
|
|
|
|
DTLS_OUTGOING_MESSAGE *msg =
|
|
&ssl->d1->outgoing_messages[ssl->d1->outgoing_messages_len];
|
|
msg->data = NULL;
|
|
msg->len = 0;
|
|
msg->epoch = ssl->d1->w_epoch;
|
|
msg->is_ccs = 1;
|
|
|
|
ssl->d1->outgoing_messages_len++;
|
|
return 1;
|
|
}
|
|
|
|
int dtls1_buffer_message(SSL *ssl) {
|
|
if (ssl->d1->outgoing_messages_len >= SSL_MAX_HANDSHAKE_FLIGHT) {
|
|
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
|
|
return 0;
|
|
}
|
|
|
|
DTLS_OUTGOING_MESSAGE *msg =
|
|
&ssl->d1->outgoing_messages[ssl->d1->outgoing_messages_len];
|
|
msg->data = BUF_memdup(ssl->init_buf->data, ssl->init_num);
|
|
if (msg->data == NULL) {
|
|
return 0;
|
|
}
|
|
msg->len = ssl->init_num;
|
|
msg->epoch = ssl->d1->w_epoch;
|
|
msg->is_ccs = 0;
|
|
|
|
ssl->d1->outgoing_messages_len++;
|
|
return 1;
|
|
}
|
|
|
|
int dtls1_send_change_cipher_spec(SSL *ssl, int a, int b) {
|
|
if (ssl->state == a) {
|
|
dtls1_buffer_change_cipher_spec(ssl);
|
|
ssl->state = b;
|
|
}
|
|
|
|
return dtls1_write_change_cipher_spec(ssl, dtls1_use_current_epoch);
|
|
}
|
|
|
|
void dtls_clear_outgoing_messages(SSL *ssl) {
|
|
size_t i;
|
|
for (i = 0; i < ssl->d1->outgoing_messages_len; i++) {
|
|
OPENSSL_free(ssl->d1->outgoing_messages[i].data);
|
|
ssl->d1->outgoing_messages[i].data = NULL;
|
|
}
|
|
ssl->d1->outgoing_messages_len = 0;
|
|
}
|
|
|
|
void dtls_clear_incoming_messages(SSL *ssl) {
|
|
size_t i;
|
|
for (i = 0; i < SSL_MAX_HANDSHAKE_FLIGHT; i++) {
|
|
dtls1_hm_fragment_free(ssl->d1->incoming_messages[i]);
|
|
ssl->d1->incoming_messages[i] = NULL;
|
|
}
|
|
}
|
|
|
|
unsigned int dtls1_min_mtu(void) {
|
|
return kMinMTU;
|
|
}
|
|
|
|
int dtls1_parse_fragment(CBS *cbs, struct hm_header_st *out_hdr,
|
|
CBS *out_body) {
|
|
memset(out_hdr, 0x00, sizeof(struct hm_header_st));
|
|
|
|
if (!CBS_get_u8(cbs, &out_hdr->type) ||
|
|
!CBS_get_u24(cbs, &out_hdr->msg_len) ||
|
|
!CBS_get_u16(cbs, &out_hdr->seq) ||
|
|
!CBS_get_u24(cbs, &out_hdr->frag_off) ||
|
|
!CBS_get_u24(cbs, &out_hdr->frag_len) ||
|
|
!CBS_get_bytes(cbs, out_body, out_hdr->frag_len)) {
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|