Support key agreement

Key agreement algorithms were excluded back when they were constructed
with a macro conveying the key agreement itself taking the KDF as an
argument, because that was hard to support. Now the encoding has
changed and key agreement algorithms are constructed with
PSA_ALG_KEY_AGREEMENT taking two arguments, one that identifies the
raw key agreement and one that identifies the KDF. This is easy to
process, so add support.

Author: gilles-peskine-arm

tests/scripts/test_psa_constant_names.py

@@ -186,10 +186,6 @@ def _argument_split(cls, arguments):
         # Auxiliary macro whose name doesn't fit the usual patterns for
         # auxiliary macros.
         'PSA_ALG_AEAD_WITH_DEFAULT_TAG_LENGTH_CASE',
-        # PSA_ALG_ECDH and PSA_ALG_FFDH are excluded for now as the script
-        # currently doesn't support them.
-        'PSA_ALG_ECDH',
-        'PSA_ALG_FFDH',
         # Deprecated aliases.
         'PSA_ERROR_UNKNOWN_ERROR',
         'PSA_ERROR_OCCUPIED_SLOT',
@@ -237,17 +233,20 @@ def add_test_case_line(self, function, argument):
         """Parse a test case data line, looking for algorithm metadata tests."""
         sets = []
         if function.endswith('_algorithm'):
-            # As above, ECDH and FFDH algorithms are excluded for now.
-            # Support for them will be added in the future.
-            if 'ECDH' in argument or 'FFDH' in argument:
-                return
             sets.append(self.algorithms)
             if function == 'hash_algorithm':
                 sets.append(self.hash_algorithms)
             elif function in ['mac_algorithm', 'hmac_algorithm']:
                 sets.append(self.mac_algorithms)
             elif function == 'aead_algorithm':
                 sets.append(self.aead_algorithms)
+            elif function == 'key_derivation_algorithm':
+                sets.append(self.kdf_algorithms)
+            elif function == 'key_agreement_algorithm':
+                # We only want *raw* key agreement algorithms here, so
+                # exclude ones that are already chained with a KDF.
+                if not argument.startswith('PSA_ALG_KEY_AGREEMENT('):
+                    sets.append(self.ka_algorithms)
         elif function == 'key_type':
             sets.append(self.key_types)
         elif function == 'ecc_key_types':