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# Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
#
# Licensed under the OpenSSL license (the "License"). You may not use
# this file except in compliance with the License. You can obtain a copy
# in the file LICENSE in the source distribution or at
# https://www.openssl.org/source/license.html
use strict;
package TLSProxy::ClientHello;
use vars '@ISA';
push @ISA, 'TLSProxy::Message';
sub new
{
my $class = shift;
my ($server,
$data,
$records,
$startoffset,
$message_frag_lens) = @_;
my $self = $class->SUPER::new(
$server,
1,
$data,
$records,
$startoffset,
$message_frag_lens);
$self->{client_version} = 0;
$self->{random} = [];
$self->{session_id_len} = 0;
$self->{session} = "";
$self->{ciphersuite_len} = 0;
$self->{ciphersuites} = [];
$self->{comp_meth_len} = 0;
$self->{comp_meths} = [];
$self->{extensions_len} = 0;
$self->{extension_data} = "";
return $self;
}
sub parse
{
my $self = shift;
my $ptr = 2;
my ($client_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 $ciphersuite_len = unpack('n', substr($self->data, $ptr));
$ptr += 2;
my @ciphersuites = unpack('n*', substr($self->data, $ptr,
$ciphersuite_len));
$ptr += $ciphersuite_len;
my $comp_meth_len = unpack('C', substr($self->data, $ptr));
$ptr++;
my @comp_meths = unpack('C*', substr($self->data, $ptr, $comp_meth_len));
$ptr += $comp_meth_len;
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;
}
$self->client_version($client_version);
$self->random($random);
$self->session_id_len($session_id_len);
$self->session($session);
$self->ciphersuite_len($ciphersuite_len);
$self->ciphersuites(\@ciphersuites);
$self->comp_meth_len($comp_meth_len);
$self->comp_meths(\@comp_meths);
$self->extensions_len($extensions_len);
$self->extension_data(\%extensions);
$self->process_extensions();
print " Client Version:".$client_version."\n";
print " Session ID Len:".$session_id_len."\n";
print " Ciphersuite len:".$ciphersuite_len."\n";
print " Compression Method Len:".$comp_meth_len."\n";
print " Extensions Len:".$extensions_len."\n";
}
#Perform any actions necessary based on the extensions we've seen
sub process_extensions
{
my $self = shift;
my %extensions = %{$self->extension_data};
#Clear any state from a previous run
TLSProxy::Record->etm(0);
if (exists $extensions{TLSProxy::Message::EXT_ENCRYPT_THEN_MAC}) {
TLSProxy::Record->etm(1);
}
}
sub extension_contents
{
my $self = shift;
my $key = shift;
my $extension = "";
my $extdata = ${$self->extension_data}{$key};
$extension .= pack("n", $key);
$extension .= pack("n", length($extdata));
$extension .= $extdata;
return $extension;
}
#Reconstruct the on-the-wire message data following changes
sub set_message_contents
{
my $self = shift;
my $data;
my $extensions = "";
$data = pack('n', $self->client_version);
$data .= $self->random;
$data .= pack('C', $self->session_id_len);
$data .= $self->session;
$data .= pack('n', $self->ciphersuite_len);
$data .= pack("n*", @{$self->ciphersuites});
$data .= pack('C', $self->comp_meth_len);
$data .= pack("C*", @{$self->comp_meths});
foreach my $key (keys %{$self->extension_data}) {
next if ($key == TLSProxy::Message::EXT_PSK);
$extensions .= $self->extension_contents($key);
#Add extension twice if we are duplicating that extension
$extensions .= $self->extension_contents($key) if ($key == $self->dupext);
}
#PSK extension always goes last...
if (defined ${$self->extension_data}{TLSProxy::Message::EXT_PSK}) {
$extensions .= $self->extension_contents(TLSProxy::Message::EXT_PSK);
}
#unless we have EXT_FORCE_LAST
if (defined ${$self->extension_data}{TLSProxy::Message::EXT_FORCE_LAST}) {
$extensions .= $self->extension_contents(TLSProxy::Message::EXT_FORCE_LAST);
}
$data .= pack('n', length($extensions));
$data .= $extensions;
$self->data($data);
}
#Read/write accessors
sub client_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_len
{
my $self = shift;
if (@_) {
$self->{ciphersuite_len} = shift;
}
return $self->{ciphersuite_len};
}
sub ciphersuites
{
my $self = shift;
if (@_) {
$self->{ciphersuites} = shift;
}
return $self->{ciphersuites};
}
sub comp_meth_len
{
my $self = shift;
if (@_) {
$self->{comp_meth_len} = shift;
}
return $self->{comp_meth_len};
}
sub comp_meths
{
my $self = shift;
if (@_) {
$self->{comp_meths} = shift;
}
return $self->{comp_meths};
}
sub extensions_len
{
my $self = shift;
if (@_) {
$self->{extensions_len} = shift;
}
return $self->{extensions_len};
}
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;
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