lib/braintree/digest.rb in braintree-2.15.0 vs lib/braintree/digest.rb in braintree-2.16.0

@@ -2,13 +2,26 @@
   module Digest # :nodoc:
     def self.hexdigest(private_key, string)
       _hmac_sha1(private_key, string)
     end
 
+    def self.secure_compare(left, right)
+      return false unless left && right
+
+      left_bytes = left.unpack("C*")
+      right_bytes = right.unpack("C*")
+      return false if left_bytes.size != right_bytes.size
+
+      result = 0
+      left_bytes.zip(right_bytes).each do |left_byte, right_byte|
+        result |= left_byte ^ right_byte
+      end
+      result == 0
+    end
+
     def self._hmac_sha1(key, message)
       key_digest = ::Digest::SHA1.digest(key)
       sha1 = OpenSSL::Digest::Digest.new("sha1")
       OpenSSL::HMAC.hexdigest(sha1, key_digest, message.to_s)
     end
   end
 end
-