Guard against PKCS1 PEM-encoded public keys

CHANGELOG.md

@@ -7,11 +7,20 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 [Unreleased][unreleased]
 -------------------------------------------------------------------------
 ### Changed
+### Fixed
+### Added
+
+[v1.5.1][1.5.1]
+-------------------------------------------------------------------------
+### Changed
 
 - Change optparse for argparse. [#238][238]
 
 ### Fixed
 
+- Guard against PKCS1 PEM encododed public keys
+- Add deprecation warning when decoding without specifying `algorithms`
+
 ### Added
 
 - Support for Python 3.6 [#262][262]
@@ -132,6 +141,7 @@ rarely used. Users affected by this should upgrade to 3.3+.
 [1.4.1]: https://github.com/jpadilla/pyjwt/compare/1.4.0...1.4.1
 [1.4.2]: https://github.com/jpadilla/pyjwt/compare/1.4.1...1.4.2
 [1.5.0]: https://github.com/jpadilla/pyjwt/compare/1.4.2...1.5.0
+[1.5.1]: https://github.com/jpadilla/pyjwt/compare/1.5.0...1.5.1
 
 [109]: https://github.com/jpadilla/pyjwt/pull/109
 [110]: https://github.com/jpadilla/pyjwt/pull/110

jwt/algorithms.py

@@ -142,6 +142,7 @@ def prepare_key(self, key):
         invalid_strings = [
             b'-----BEGIN PUBLIC KEY-----',
             b'-----BEGIN CERTIFICATE-----',
+            b'-----BEGIN RSA PUBLIC KEY-----',
             b'ssh-rsa'
         ]
 

jwt/api_jws.py

@@ -117,6 +117,15 @@ def encode(self, payload, key, algorithm='HS256', headers=None,
 
     def decode(self, jws, key='', verify=True, algorithms=None, options=None,
                **kwargs):
+
+        if not algorithms:
+            warnings.warn(
+                'It is strongly recommended that you pass in a ' +
+                'value for the "algorithms" argument when calling decode(). ' +
+                'This argument will be mandatory in a future version.',
+                DeprecationWarning
+            )
+
         payload, signing_input, header, signature = self._load(jws)
 
         if verify:

jwt/api_jwt.py

@@ -58,6 +58,15 @@ def encode(self, payload, key, algorithm='HS256', headers=None,
 
     def decode(self, jwt, key='', verify=True, algorithms=None, options=None,
                **kwargs):
+
+        if not algorithms:
+            warnings.warn(
+                'It is strongly recommended that you pass in a ' +
+                'value for the "algorithms" argument when calling decode(). ' +
+                'This argument will be mandatory in a future version.',
+                DeprecationWarning
+            )
+
         payload, signing_input, header, signature = self._load(jwt)
 
         decoded = super(PyJWT, self).decode(jwt, key, verify, algorithms,

tests/keys/testkey_pkcs1.pub.pem

@@ -0,0 +1,5 @@
+-----BEGIN RSA PUBLIC KEY-----
+MIGHAoGBAOV/0Vl/5VdHcYpnILYzBGWo5JQVzo9wBkbxzjAStcAnTwvv1ZJTMXs6
+fjz91f9hiMM4Z/5qNTE/EHlDWxVdj1pyRaQulZPUs0r9qJ02ogRRGLG3jjrzzbzF
+yj/pdNBwym0UJYC/Jmn/kMLwGiWI2nfa9vM5SovqZiAy2FD7eOtVAgED
+-----END RSA PUBLIC KEY-----

tests/test_algorithms.py

@@ -97,6 +97,13 @@ def test_hmac_should_throw_exception_if_key_is_x509_cert(self):
             with open(key_path('testkey2_rsa.pub.pem'), 'r') as keyfile:
                 algo.prepare_key(keyfile.read())
 
+    def test_hmac_should_throw_exception_if_key_is_pkcs1_pem_public(self):
+        algo = HMACAlgorithm(HMACAlgorithm.SHA256)
+
+        with pytest.raises(InvalidKeyError):
+            with open(key_path('testkey_pkcs1.pub.pem'), 'r') as keyfile:
+                algo.prepare_key(keyfile.read())
+
     def test_hmac_jwk_should_parse_and_verify(self):
         algo = HMACAlgorithm(HMACAlgorithm.SHA256)
 

tests/test_api_jws.py

@@ -265,6 +265,16 @@ def test_verify_false_deprecated(self, jws, recwarn):
 
         pytest.deprecated_call(jws.decode, example_jws, verify=False)
 
+    def test_decode_with_optional_algorithms(self, jws):
+        example_secret = 'secret'
+        example_jws = (
+            b'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.'
+            b'aGVsbG8gd29ybGQ.'
+            b'SIr03zM64awWRdPrAM_61QWsZchAtgDV3pphfHPPWkI'
+        )
+
+        pytest.deprecated_call(jws.decode, example_jws, key=example_secret)
+
     def test_load_no_verification(self, jws, payload):
         right_secret = 'foo'
         jws_message = jws.encode(payload, right_secret)

tests/test_api_jwt.py

@@ -472,3 +472,13 @@ def test_decode_with_verify_expiration_kwarg(self, jwt, payload):
                 secret,
                 verify_expiration=True
             )
+
+    def test_decode_with_optional_algorithms(self, jwt, payload):
+        secret = 'secret'
+        jwt_message = jwt.encode(payload, secret)
+
+        pytest.deprecated_call(
+            jwt.decode,
+            jwt_message,
+            secret
+        )