checksum: drop pycrypto/pycryptodome fallback for BLAKE2/SHA3

Included with >= Python 3.6 and we weren't testing these codepaths anyway.

Signed-off-by: Sam James <[email protected]>

lib/portage/checksum.py

@@ -27,10 +27,10 @@
 # SHA512: hashlib
 # RMD160: hashlib, pycrypto, mhash
 # WHIRLPOOL: hashlib, mhash, bundled (C), bundled (Python)
-# BLAKE2B (512): hashlib, pycrypto
-# BLAKE2S (512): hashlib,pycrypto
-# SHA3_256: hashlib, pycrypto
-# SHA3_512: hashlib, pycrypto
+# BLAKE2B (512): hashlib
+# BLAKE2S (512): hashlib
+# SHA3_256: hashlib
+# SHA3_512: hashlib
 
 
 # Dict of all available hash functions
@@ -138,53 +138,6 @@ def checksum_file(self, filename):
     except ImportError:
         pass
 
-# The following hashes were added in pycryptodome (pycrypto fork)
-if "BLAKE2B" not in hashfunc_map:
-    try:
-        from Crypto.Hash import BLAKE2b
-
-        blake2bhash_ = getattr(BLAKE2b, "new", None)
-        if blake2bhash_ is not None:
-            _generate_hash_function(
-                "BLAKE2B",
-                functools.partial(blake2bhash_, digest_bytes=64),
-                origin="pycrypto",
-            )
-    except ImportError:
-        pass
-
-if "BLAKE2S" not in hashfunc_map:
-    try:
-        from Crypto.Hash import BLAKE2s
-
-        blake2shash_ = getattr(BLAKE2s, "new", None)
-        if blake2shash_ is not None:
-            _generate_hash_function(
-                "BLAKE2S",
-                functools.partial(blake2shash_, digest_bytes=32),
-                origin="pycrypto",
-            )
-    except ImportError:
-        pass
-
-if "SHA3_256" not in hashfunc_map:
-    try:
-        from Crypto.Hash import SHA3_256
-
-        sha3_256hash_ = getattr(SHA3_256, "new", None)
-        if sha3_256hash_ is not None:
-            _generate_hash_function("SHA3_256", sha3_256hash_, origin="pycrypto")
-    except ImportError:
-        pass
-
-if "SHA3_512" not in hashfunc_map:
-    try:
-        from Crypto.Hash import SHA3_512
-
-        sha3_512hash_ = getattr(SHA3_512, "new", None)
-        if sha3_512hash_ is not None:
-            _generate_hash_function("SHA3_512", sha3_512hash_, origin="pycrypto")
-    except ImportError:
         pass