util/perl/TLSProxy/ServerHello.pm

   1 # Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
   2 #
   3 # Licensed under the Apache License 2.0 (the "License").  You may not use
   4 # this file except in compliance with the License.  You can obtain a copy
   5 # in the file LICENSE in the source distribution or at
   6 # https://www.openssl.org/source/license.html
   7
   8 use strict;
   9
  10 package TLSProxy::ServerHello;
  11
  12 use TLSProxy::Record;
  13
  14 use vars '@ISA';
  15 push @ISA, 'TLSProxy::Message';
  16
  17 my $hrrrandom = pack("C*", 0xCF, 0x21, 0xAD, 0x74, 0xE5, 0x9A, 0x61, 0x11, 0xBE,
  18                            0x1D, 0x8C, 0x02, 0x1E, 0x65, 0xB8, 0x91, 0xC2, 0xA2,
  19                            0x11, 0x16, 0x7A, 0xBB, 0x8C, 0x5E, 0x07, 0x9E, 0x09,
  20                            0xE2, 0xC8, 0xA8, 0x33, 0x9C);
  21
  22 sub new
  23 {
  24     my $class = shift;
  25     my ($isdtls,
  26         $server,
  27         $msgseq,
  28         $msgfrag,
  29         $msgfragoffs,
  30         $data,
  31         $records,
  32         $startoffset,
  33         $message_frag_lens) = @_;
  34
  35     my $self = $class->SUPER::new(
  36         $isdtls,
  37         $server,
  38         TLSProxy::Message::MT_SERVER_HELLO,
  39         $msgseq,
  40         $msgfrag,
  41         $msgfragoffs,
  42         $data,
  43         $records,
  44         $startoffset,
  45         $message_frag_lens);
  46
  47     $self->{server_version} = 0;
  48     $self->{random} = [];
  49     $self->{session_id_len} = 0;
  50     $self->{session} = "";
  51     $self->{ciphersuite} = 0;
  52     $self->{comp_meth} = 0;
  53     $self->{extension_data} = "";
  54
  55     return $self;
  56 }
  57
  58 sub parse
  59 {
  60     my $self = shift;
  61     my $ptr = 2;
  62     my ($server_version) = unpack('n', $self->data);
  63     my $neg_version = $server_version;
  64
  65     my $random = substr($self->data, $ptr, 32);
  66     $ptr += 32;
  67     my $session_id_len = 0;
  68     my $session = "";
  69     $session_id_len = unpack('C', substr($self->data, $ptr));
  70     $ptr++;
  71     $session = substr($self->data, $ptr, $session_id_len);
  72     $ptr += $session_id_len;
  73
  74     my $ciphersuite = unpack('n', substr($self->data, $ptr));
  75     $ptr += 2;
  76     my $comp_meth = 0;
  77     $comp_meth = unpack('C', substr($self->data, $ptr));
  78     $ptr++;
  79
  80     my $extensions_len = unpack('n', substr($self->data, $ptr));
  81     if (!defined $extensions_len) {
  82         $extensions_len = 0;
  83     } else {
  84         $ptr += 2;
  85     }
  86     #For now we just deal with this as a block of data. In the future we will
  87     #want to parse this
  88     my $extension_data;
  89     if ($extensions_len != 0) {
  90         $extension_data = substr($self->data, $ptr);
  91
  92         if (length($extension_data) != $extensions_len) {
  93             die "Invalid extension length\n";
  94         }
  95     } else {
  96         if (length($self->data) != $ptr) {
  97             die "Invalid extension length\n";
  98         }
  99         $extension_data = "";
 100     }
 101     my %extensions = ();
 102     while (length($extension_data) >= 4) {
 103         my ($type, $size) = unpack("nn", $extension_data);
 104         my $extdata = substr($extension_data, 4, $size);
 105         $extension_data = substr($extension_data, 4 + $size);
 106         $extensions{$type} = $extdata;
 107         if ($type == TLSProxy::Message::EXT_SUPPORTED_VERSIONS) {
 108             $neg_version = unpack('n', $extdata);
 109         }
 110     }
 111
 112     if ($random eq $hrrrandom) {
 113         TLSProxy::Proxy->is_tls13(1);
 114     } elsif ($neg_version == TLSProxy::Record::VERS_TLS_1_3) {
 115         TLSProxy::Proxy->is_tls13(1);
 116
 117         TLSProxy::Record->server_encrypting(1);
 118         TLSProxy::Record->client_encrypting(1);
 119     }
 120
 121     $self->server_version($server_version);
 122     $self->random($random);
 123     $self->session_id_len($session_id_len);
 124     $self->session($session);
 125     $self->ciphersuite($ciphersuite);
 126     TLSProxy::Proxy->ciphersuite($ciphersuite);
 127     $self->comp_meth($comp_meth);
 128     $self->extension_data(\%extensions);
 129
 130     $self->process_data();
 131
 132
 133     print "    Server Version:".$TLSProxy::Record::tls_version{$server_version}."\n";
 134     print "    Session ID Len:".$session_id_len."\n";
 135     print "    Ciphersuite:".$ciphersuite."\n";
 136     print "    Compression Method:".$comp_meth."\n";
 137     print "    Extensions Len:".$extensions_len."\n";
 138 }
 139
 140 #Perform any actions necessary based on the data we've seen
 141 sub process_data
 142 {
 143     my $self = shift;
 144
 145     TLSProxy::Message->ciphersuite($self->ciphersuite);
 146 }
 147
 148 #Reconstruct the on-the-wire message data following changes
 149 sub set_message_contents
 150 {
 151     my $self = shift;
 152     my $data;
 153     my $extensions = "";
 154
 155     $data = pack('n', $self->server_version);
 156     $data .= $self->random;
 157     $data .= pack('C', $self->session_id_len);
 158     $data .= $self->session;
 159     $data .= pack('n', $self->ciphersuite);
 160     $data .= pack('C', $self->comp_meth);
 161
 162     foreach my $key (keys %{$self->extension_data}) {
 163         my $extdata = ${$self->extension_data}{$key};
 164         $extensions .= pack("n", $key);
 165         $extensions .= pack("n", length($extdata));
 166         $extensions .= $extdata;
 167         if ($key == $self->dupext) {
 168           $extensions .= pack("n", $key);
 169           $extensions .= pack("n", length($extdata));
 170           $extensions .= $extdata;
 171         }
 172     }
 173
 174     $data .= pack('n', length($extensions));
 175     $data .= $extensions;
 176     $self->data($data);
 177 }
 178
 179 #Read/write accessors
 180 sub server_version
 181 {
 182     my $self = shift;
 183     if (@_) {
 184       $self->{server_version} = shift;
 185     }
 186     return $self->{server_version};
 187 }
 188 sub random
 189 {
 190     my $self = shift;
 191     if (@_) {
 192       $self->{random} = shift;
 193     }
 194     return $self->{random};
 195 }
 196 sub session_id_len
 197 {
 198     my $self = shift;
 199     if (@_) {
 200       $self->{session_id_len} = shift;
 201     }
 202     return $self->{session_id_len};
 203 }
 204 sub session
 205 {
 206     my $self = shift;
 207     if (@_) {
 208       $self->{session} = shift;
 209     }
 210     return $self->{session};
 211 }
 212 sub ciphersuite
 213 {
 214     my $self = shift;
 215     if (@_) {
 216       $self->{ciphersuite} = shift;
 217     }
 218     return $self->{ciphersuite};
 219 }
 220 sub comp_meth
 221 {
 222     my $self = shift;
 223     if (@_) {
 224       $self->{comp_meth} = shift;
 225     }
 226     return $self->{comp_meth};
 227 }
 228 sub extension_data
 229 {
 230     my $self = shift;
 231     if (@_) {
 232       $self->{extension_data} = shift;
 233     }
 234     return $self->{extension_data};
 235 }
 236 sub set_extension
 237 {
 238     my ($self, $ext_type, $ext_data) = @_;
 239     $self->{extension_data}{$ext_type} = $ext_data;
 240 }
 241 sub delete_extension
 242 {
 243     my ($self, $ext_type) = @_;
 244     delete $self->{extension_data}{$ext_type};
 245 }
 246 1;