openssl/util/TLSProxy/ServerHello.pm
Emilia Kasper aa474d1fb1 TLS: reject duplicate extensions
Adapted from BoringSSL. Added a test.

The extension parsing code is already attempting to already handle this for
some individual extensions, but it is doing so inconsistently. Duplicate
efforts in individual extension parsing will be cleaned up in a follow-up.

Reviewed-by: Stephen Henson <steve@openssl.org>
2016-02-19 17:24:44 +01:00

244 lines
7.0 KiB
Perl

# Written by Matt Caswell for the OpenSSL project.
# ====================================================================
# Copyright (c) 1998-2015 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).
use strict;
package TLSProxy::ServerHello;
use parent 'TLSProxy::Message';
sub new
{
my $class = shift;
my ($server,
$data,
$records,
$startoffset,
$message_frag_lens) = @_;
my $self = $class->SUPER::new(
$server,
TLSProxy::Message::MT_SERVER_HELLO,
$data,
$records,
$startoffset,
$message_frag_lens);
$self->{server_version} = 0;
$self->{random} = [];
$self->{session_id_len} = 0;
$self->{session} = "";
$self->{ciphersuite} = 0;
$self->{comp_meth} = 0;
$self->{extension_data} = "";
return $self;
}
sub parse
{
my $self = shift;
my $ptr = 2;
my ($server_version) = unpack('n', $self->data);
my $random = substr($self->data, $ptr, 32);
$ptr += 32;
my $session_id_len = unpack('C', substr($self->data, $ptr));
$ptr++;
my $session = substr($self->data, $ptr, $session_id_len);
$ptr += $session_id_len;
my $ciphersuite = unpack('n', substr($self->data, $ptr));
$ptr += 2;
my $comp_meth = unpack('C', substr($self->data, $ptr));
$ptr++;
my $extensions_len = unpack('n', substr($self->data, $ptr));
$ptr += 2;
#For now we just deal with this as a block of data. In the future we will
#want to parse this
my $extension_data = substr($self->data, $ptr);
if (length($extension_data) != $extensions_len) {
die "Invalid extension length\n";
}
my %extensions = ();
while (length($extension_data) >= 4) {
my ($type, $size) = unpack("nn", $extension_data);
my $extdata = substr($extension_data, 4, $size);
$extension_data = substr($extension_data, 4 + $size);
$extensions{$type} = $extdata;
}
$self->server_version($server_version);
$self->random($random);
$self->session_id_len($session_id_len);
$self->session($session);
$self->ciphersuite($ciphersuite);
$self->comp_meth($comp_meth);
$self->extension_data(\%extensions);
$self->process_data();
print " Server Version:".$server_version."\n";
print " Session ID Len:".$session_id_len."\n";
print " Ciphersuite:".$ciphersuite."\n";
print " Compression Method:".$comp_meth."\n";
print " Extensions Len:".$extensions_len."\n";
}
#Perform any actions necessary based on the data we've seen
sub process_data
{
my $self = shift;
TLSProxy::Message->ciphersuite($self->ciphersuite);
}
#Reconstruct the on-the-wire message data following changes
sub set_message_contents
{
my $self = shift;
my $data;
my $extensions = "";
$data = pack('n', $self->server_version);
$data .= $self->random;
$data .= pack('C', $self->session_id_len);
$data .= $self->session;
$data .= pack('n', $self->ciphersuite);
$data .= pack('C', $self->comp_meth);
foreach my $key (keys %{$self->extension_data}) {
my $extdata = ${$self->extension_data}{$key};
$extensions .= pack("n", $key);
$extensions .= pack("n", length($extdata));
$extensions .= $extdata;
if ($key == TLSProxy::Message::EXT_DUPLICATE_EXTENSION) {
$extensions .= pack("n", $key);
$extensions .= pack("n", length($extdata));
$extensions .= $extdata;
}
}
$data .= pack('n', length($extensions));
$data .= $extensions;
$self->data($data);
}
#Read/write accessors
sub server_version
{
my $self = shift;
if (@_) {
$self->{client_version} = shift;
}
return $self->{client_version};
}
sub random
{
my $self = shift;
if (@_) {
$self->{random} = shift;
}
return $self->{random};
}
sub session_id_len
{
my $self = shift;
if (@_) {
$self->{session_id_len} = shift;
}
return $self->{session_id_len};
}
sub session
{
my $self = shift;
if (@_) {
$self->{session} = shift;
}
return $self->{session};
}
sub ciphersuite
{
my $self = shift;
if (@_) {
$self->{ciphersuite} = shift;
}
return $self->{ciphersuite};
}
sub comp_meth
{
my $self = shift;
if (@_) {
$self->{comp_meth} = shift;
}
return $self->{comp_meth};
}
sub extension_data
{
my $self = shift;
if (@_) {
$self->{extension_data} = shift;
}
return $self->{extension_data};
}
sub set_extension
{
my ($self, $ext_type, $ext_data) = @_;
$self->{extension_data}{$ext_type} = $ext_data;
}
sub delete_extension
{
my ($self, $ext_type) = @_;
delete $self->{extension_data}{$ext_type};
}
1;