Module: RbNaCl::KeyComparator

Includes:
Comparable
Included in:
Boxes::Curve25519XSalsa20Poly1305::PrivateKey, Boxes::Curve25519XSalsa20Poly1305::PublicKey, GroupElements::Curve25519, Signatures::Ed25519::SigningKey, Signatures::Ed25519::VerifyKey
Defined in:
lib/rbnacl/key_comparator.rb

Overview

Implements comparisons of keys

This permits both timing invariant equality tests, as well as lexicographical sorting.

Instance Method Summary collapse

Instance Method Details

#<=>(other) ⇒ 0, ...

spaceship operator

Parameters:

Returns:

  • (0) —

    if the keys are equal

  • (1) —

    if the key is larger than the other key

  • (-1) —

    if the key is smaller than the other key

  • (nil) —

    if comparison doesn't make sense



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# File 'lib/rbnacl/key_comparator.rb', line 17

def <=>(other)
  if KeyComparator > other.class
    other = other.to_bytes
  elsif other.respond_to?(:to_str)
    other = other.to_str
  else
    return nil
  end

  if Util.verify32(self.to_bytes, other)
    return 0
  elsif self.to_bytes > other
    return 1
  else
    return -1
  end
end

#==(other) ⇒ true, false

equality operator

The equality operator is explicity defined, despite including Comparable and having a spaceship operator, so that if equality tests are desired, they can be timing invariant, without any chance that the further comparisons for greater than and less than can leak information. Maybe this is too paranoid, but I don't know how ruby works under the hood with comparable.

Parameters:

Returns:

  • (true) —

    if the keys are equal

  • (false) —

    if they keys are not equal



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# File 'lib/rbnacl/key_comparator.rb', line 48

def ==(other)
  if KeyComparator > other.class
    other = other.to_bytes
  elsif other.respond_to?(:to_str)
    other = other.to_str
  else
    return false
  end
  Util.verify32(self.to_bytes, other)
end