lib/jwt.rb in jwt-1.5.0 vs lib/jwt.rb in jwt-1.5.1

@@ -1,15 +1,15 @@
-#
-# JSON Web Token implementation
-#
-# Should be up to date with the latest spec:
-# http://self-issued.info/docs/draft-jones-json-web-token-06.html
+# encoding: utf-8
 
 require 'base64'
 require 'openssl'
 require 'jwt/json'
 
+# JSON Web Token implementation
+#
+# Should be up to date with the latest spec:
+# http://self-issued.info/docs/draft-jones-json-web-token-06.html
 module JWT
   class DecodeError < StandardError; end
   class VerificationError < DecodeError; end
   class ExpiredSignature < DecodeError; end
   class IncorrectAlgorithm < DecodeError; end
@@ -22,11 +22,11 @@
   extend JWT::Json
 
   NAMED_CURVES = {
     'prime256v1' => 'ES256',
     'secp384r1' => 'ES384',
-    'secp521r1' => 'ES512',
+    'secp521r1' => 'ES512'
   }
 
   module_function
 
   def sign(algorithm, msg, key)
@@ -35,40 +35,40 @@
     elsif ['RS256', 'RS384', 'RS512'].include?(algorithm)
       sign_rsa(algorithm, msg, key)
     elsif ['ES256', 'ES384', 'ES512'].include?(algorithm)
       sign_ecdsa(algorithm, msg, key)
     else
-      raise NotImplementedError.new('Unsupported signing method')
+      fail NotImplementedError.new('Unsupported signing method')
     end
   end
 
   def sign_rsa(algorithm, msg, private_key)
     private_key.sign(OpenSSL::Digest.new(algorithm.sub('RS', 'sha')), msg)
   end
 
   def sign_ecdsa(algorithm, msg, private_key)
     key_algorithm = NAMED_CURVES[private_key.group.curve_name]
     if algorithm != key_algorithm
-      raise IncorrectAlgorithm.new("payload algorithm is #{algorithm} but #{key_algorithm} signing key was provided")
+      fail IncorrectAlgorithm.new("payload algorithm is #{algorithm} but #{key_algorithm} signing key was provided")
     end
 
     digest = OpenSSL::Digest.new(algorithm.sub('ES', 'sha'))
-    private_key.dsa_sign_asn1(digest.digest(msg))
+    asn1_to_raw(private_key.dsa_sign_asn1(digest.digest(msg)), private_key)
   end
 
   def verify_rsa(algorithm, public_key, signing_input, signature)
     public_key.verify(OpenSSL::Digest.new(algorithm.sub('RS', 'sha')), signature, signing_input)
   end
 
   def verify_ecdsa(algorithm, public_key, signing_input, signature)
     key_algorithm = NAMED_CURVES[public_key.group.curve_name]
     if algorithm != key_algorithm
-      raise IncorrectAlgorithm.new("payload algorithm is #{algorithm} but #{key_algorithm} verification key was provided")
+      fail IncorrectAlgorithm.new("payload algorithm is #{algorithm} but #{key_algorithm} verification key was provided")
     end
 
     digest = OpenSSL::Digest.new(algorithm.sub('ES', 'sha'))
-    public_key.dsa_verify_asn1(digest.digest(signing_input), signature)
+    public_key.dsa_verify_asn1(digest.digest(signing_input), raw_to_asn1(signature, public_key))
   end
 
   def sign_hmac(algorithm, msg, key)
     OpenSSL::HMAC.digest(OpenSSL::Digest.new(algorithm.sub('HS', 'sha')), key, msg)
   end
@@ -81,11 +81,11 @@
   def base64url_encode(str)
     Base64.encode64(str).tr('+/', '-_').gsub(/[\n=]/, '')
   end
 
   def encoded_header(algorithm='HS256', header_fields={})
-    header = {'typ' => 'JWT', 'alg' => algorithm}.merge(header_fields)
+    header = { 'typ' => 'JWT', 'alg' => algorithm }.merge(header_fields)
     base64url_encode(encode_json(header))
   end
 
   def encoded_payload(payload)
     base64url_encode(encode_json(payload))
@@ -109,12 +109,12 @@
     segments.join('.')
   end
 
   def raw_segments(jwt, verify=true)
     segments = jwt.split('.')
-    required_num_segments = verify ? [3] : [2,3]
-    raise JWT::DecodeError.new('Not enough or too many segments') unless required_num_segments.include? segments.length
+    required_num_segments = verify ? [3] : [2, 3]
+    fail JWT::DecodeError.new('Not enough or too many segments') unless required_num_segments.include? segments.length
     segments
   end
 
   def decode_header_and_payload(header_segment, payload_segment)
     header = decode_json(base64url_decode(header_segment))
@@ -129,14 +129,14 @@
     signing_input = [header_segment, payload_segment].join('.')
     [header, payload, signature, signing_input]
   end
 
   def decode(jwt, key=nil, verify=true, options={}, &keyfinder)
-    raise JWT::DecodeError.new('Nil JSON web token') unless jwt
+    fail JWT::DecodeError.new('Nil JSON web token') unless jwt
 
     header, payload, signature, signing_input = decoded_segments(jwt, verify)
-    raise JWT::DecodeError.new('Not enough or too many segments') unless header && payload
+    fail JWT::DecodeError.new('Not enough or too many segments') unless header && payload
 
     default_options = {
       :verify_expiration => true,
       :verify_not_before => true,
       :verify_iss => false,
@@ -150,68 +150,64 @@
     options = default_options.merge(options)
 
     if verify
       algo, key = signature_algorithm_and_key(header, key, &keyfinder)
       if options[:algorithm] && algo != options[:algorithm]
-        raise JWT::IncorrectAlgorithm.new('Expected a different algorithm')
+        fail JWT::IncorrectAlgorithm.new('Expected a different algorithm')
       end
       verify_signature(algo, key, signing_input, signature)
     end
 
     if options[:verify_expiration] && payload.include?('exp')
-      raise JWT::ExpiredSignature.new('Signature has expired') unless payload['exp'].to_i > (Time.now.to_i - options[:leeway])
+      fail JWT::ExpiredSignature.new('Signature has expired') unless payload['exp'].to_i > (Time.now.to_i - options[:leeway])
     end
     if options[:verify_not_before] && payload.include?('nbf')
-      raise JWT::ImmatureSignature.new('Signature nbf has not been reached') unless payload['nbf'].to_i < (Time.now.to_i + options[:leeway])
+      fail JWT::ImmatureSignature.new('Signature nbf has not been reached') unless payload['nbf'].to_i < (Time.now.to_i + options[:leeway])
     end
-    if options[:verify_iss] && payload.include?('iss')
-      raise JWT::InvalidIssuerError.new("Invalid issuer. Expected #{options['iss']}, received #{payload['iss']}") unless payload['iss'].to_s == options['iss'].to_s
+    if options[:verify_iss] && options['iss']
+      fail JWT::InvalidIssuerError.new("Invalid issuer. Expected #{options['iss']}, received #{payload['iss'] || '<none>'}") unless payload['iss'].to_s == options['iss'].to_s
     end
     if options[:verify_iat] && payload.include?('iat')
-      raise JWT::InvalidIatError.new('Invalid iat') unless (payload['iat'].is_a?(Integer) and payload['iat'].to_i <= Time.now.to_i)
+      fail JWT::InvalidIatError.new('Invalid iat') unless payload['iat'].is_a?(Integer) && payload['iat'].to_i <= Time.now.to_i
     end
-    if options[:verify_aud] && payload.include?('aud')
+    if options[:verify_aud] && options['aud']
       if payload['aud'].is_a?(Array)
-        raise JWT::InvalidAudError.new('Invalid audience') unless payload['aud'].include?(options['aud'])
+        fail JWT::InvalidAudError.new('Invalid audience') unless payload['aud'].include?(options['aud'].to_s)
       else
-        raise JWT::InvalidAudError.new("Invalid audience. Expected #{options['aud']}, received #{payload['aud']}") unless payload['aud'].to_s == options['aud'].to_s
+        fail JWT::InvalidAudError.new("Invalid audience. Expected #{options['aud']}, received #{payload['aud'] || '<none>'}") unless payload['aud'].to_s == options['aud'].to_s
       end
     end
     if options[:verify_sub] && payload.include?('sub')
-      raise JWT::InvalidSubError.new("Invalid subject. Expected #{options['sub']}, received #{payload['sub']}") unless payload['sub'].to_s == options['sub'].to_s
+      fail JWT::InvalidSubError.new("Invalid subject. Expected #{options['sub']}, received #{payload['sub']}") unless payload['sub'].to_s == options['sub'].to_s
     end
     if options[:verify_jti] && payload.include?('jti')
-      raise JWT::InvalidJtiError.new('need iat for verify jwt id') unless payload.include?('iat')
-      raise JWT::InvalidJtiError.new('Not a uniq jwt id') unless options['jti'].to_s == Digest::MD5.hexdigest("#{key}:#{payload['iat']}")
+      fail JWT::InvalidJtiError.new('need iat for verify jwt id') unless payload.include?('iat')
+      fail JWT::InvalidJtiError.new('Not a uniq jwt id') unless options['jti'].to_s == Digest::MD5.hexdigest("#{key}:#{payload['iat']}")
     end
 
-    return payload,header
+    [payload, header]
   end
 
   def signature_algorithm_and_key(header, key, &keyfinder)
-    if keyfinder
-      key = keyfinder.call(header)
-    end
+    key = keyfinder.call(header) if keyfinder
     [header['alg'], key]
   end
 
   def verify_signature(algo, key, signing_input, signature)
-    begin
-      if ['HS256', 'HS384', 'HS512'].include?(algo)
-        raise JWT::VerificationError.new('Signature verification failed') unless secure_compare(signature, sign_hmac(algo, signing_input, key))
-      elsif ['RS256', 'RS384', 'RS512'].include?(algo)
-        raise JWT::VerificationError.new('Signature verification failed') unless verify_rsa(algo, key, signing_input, signature)
-      elsif ['ES256', 'ES384', 'ES512'].include?(algo)
-        raise JWT::VerificationError.new('Signature verification failed') unless verify_ecdsa(algo, key, signing_input, signature)
-      else
-        raise JWT::VerificationError.new('Algorithm not supported')
-      end
-    rescue OpenSSL::PKey::PKeyError
-      raise JWT::VerificationError.new('Signature verification failed')
-    ensure
-      OpenSSL.errors.clear
+    if ['HS256', 'HS384', 'HS512'].include?(algo)
+      fail JWT::VerificationError.new('Signature verification failed') unless secure_compare(signature, sign_hmac(algo, signing_input, key))
+    elsif ['RS256', 'RS384', 'RS512'].include?(algo)
+      fail JWT::VerificationError.new('Signature verification failed') unless verify_rsa(algo, key, signing_input, signature)
+    elsif ['ES256', 'ES384', 'ES512'].include?(algo)
+      fail JWT::VerificationError.new('Signature verification failed') unless verify_ecdsa(algo, key, signing_input, signature)
+    else
+      fail JWT::VerificationError.new('Algorithm not supported')
     end
+  rescue OpenSSL::PKey::PKeyError
+    raise JWT::VerificationError.new('Signature verification failed')
+  ensure
+    OpenSSL.errors.clear
   end
 
   # From devise
   # constant-time comparison algorithm to prevent timing attacks
   def secure_compare(a, b)
@@ -221,6 +217,17 @@
     res = 0
     b.each_byte { |byte| res |= byte ^ l.shift }
     res == 0
   end
 
+  def raw_to_asn1(signature, private_key)
+    byte_size = (private_key.group.degree + 7) / 8
+    r = signature[0..(byte_size - 1)]
+    s = signature[byte_size..-1]
+    OpenSSL::ASN1::Sequence.new([r, s].map { |int| OpenSSL::ASN1::Integer.new(OpenSSL::BN.new(int, 2)) }).to_der
+  end
+
+  def asn1_to_raw(signature, public_key)
+    byte_size = (public_key.group.degree + 7) / 8
+    OpenSSL::ASN1.decode(signature).value.map { |value| value.value.to_s(2).rjust(byte_size, "\x00") }.join
+  end
 end