diff options
Diffstat (limited to 'www/rt42/files/patch-lib_RT_Util.pm')
-rw-r--r-- | www/rt42/files/patch-lib_RT_Util.pm | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/www/rt42/files/patch-lib_RT_Util.pm b/www/rt42/files/patch-lib_RT_Util.pm new file mode 100644 index 0000000..4784c49 --- /dev/null +++ b/www/rt42/files/patch-lib_RT_Util.pm @@ -0,0 +1,70 @@ +--- lib/RT/Util.pm.orig 2016-06-08 21:49:02 UTC ++++ lib/RT/Util.pm +@@ -54,6 +54,8 @@ use warnings; + use base 'Exporter'; + our @EXPORT = qw/safe_run_child mime_recommended_filename/; + ++use Encode qw/encode/; ++ + sub safe_run_child (&) { + my $our_pid = $$; + +@@ -150,6 +152,58 @@ sub assert_bytes { + } + + ++=head2 C<constant_time_eq($a, $b)> ++ ++Compares two strings for equality in constant-time. Replacement for the C<eq> ++operator designed to avoid timing side-channel vulnerabilities. Returns zero ++or one. ++ ++This is intended for use in cryptographic subsystems for comparing well-formed ++data such as hashes - not for direct use with user input or as a general ++replacement for the C<eq> operator. ++ ++The two string arguments B<MUST> be of equal length. If the lengths differ, ++this function will call C<die()>, as proceeding with execution would create ++a timing vulnerability. Length is defined by characters, not bytes. ++ ++This code has been tested to do what it claims. Do not change it without ++thorough statistical timing analysis to validate the changes. ++ ++Added to resolve CVE-2017-5361 ++ ++For more on timing attacks, see this Wikipedia article: ++B<https://en.wikipedia.org/wiki/Timing_attack> ++ ++=cut ++ ++sub constant_time_eq { ++ my ($a, $b) = @_; ++ ++ my $result = 0; ++ ++ # generic error message avoids potential information leaks ++ my $generic_error = "Cannot compare values"; ++ die $generic_error unless defined $a and defined $b; ++ die $generic_error unless length $a == length $b; ++ die $generic_error if ref($a) or ref($b); ++ ++ for (my $i = 0; $i < length($a); $i++) { ++ my $a_char = substr($a, $i, 1); ++ my $b_char = substr($b, $i, 1); ++ ++ # encode() is set to die on malformed ++ my @a_octets = unpack("C*", encode('UTF-8', $a_char, Encode::FB_CROAK)); ++ my @b_octets = unpack("C*", encode('UTF-8', $b_char, Encode::FB_CROAK)); ++ die $generic_error if (scalar @a_octets) != (scalar @b_octets); ++ ++ for (my $j = 0; $j < scalar @a_octets; $j++) { ++ $result |= $a_octets[$j] ^ $b_octets[$j]; ++ } ++ } ++ return 0 + not $result; ++} ++ ++ + RT::Base->_ImportOverlays(); + + 1; |