Avoid checksum generation when not desired to circumvent FIPS problems

pyartifactory/models/artifact.py

@@ -6,7 +6,7 @@
 import hashlib
 from datetime import datetime
 from pathlib import Path
-from typing import Any, Callable, Dict, List, Literal, Optional, Union
+from typing import Callable, Dict, List, Literal, Optional, Union
 
 from pydantic import BaseModel
 
@@ -18,14 +18,28 @@ class Checksums(BaseModel):
     md5: str
     sha256: str
 
+    @staticmethod
+    def get_hasher(func: Callable[..., hashlib._Hash]) -> hashlib._Hash:
+        # In Python 3.9+, some hash algorithms (like md5, sha1, sha256) may be disabled in FIPS-compliant systems
+        # unless 'usedforsecurity=False' is specified. This flag allows the hash function to be used for non-security
+        # purposes such as checksums, even in FIPS environments.
+        try:
+            return func(usedforsecurity=False)
+        except TypeError:
+            return func()
+
     @classmethod
     def generate(cls, file_: Path) -> Checksums:
         block_size: int = 65536
-        mapping: dict[str, Callable[[], Any]] = {"md5": hashlib.md5, "sha1": hashlib.sha1, "sha256": hashlib.sha256}
+        mapping = {
+            "md5": hashlib.md5,
+            "sha1": hashlib.sha1,
+            "sha256": hashlib.sha256,
+        }
         results = {}
 
         for algorithm, hashing_function in mapping.items():
-            hasher = hashing_function()
+            hasher = cls.get_hasher(hashing_function)
             with file_.absolute().open("rb") as fd:
                 buf = fd.read(block_size)
                 while len(buf) > 0:

tests/test_artifacts.py

@@ -612,6 +612,54 @@ def test_checksum_defined_file(file_path: Path, expected_sha1: str, expected_md5
     assert result == expected
 
 
+def test_get_hasher_security_flag():
+    calls = {"kwargs": None}
+
+    class Dummy:
+        def __init__(self):
+            self._buf = b""
+
+        def update(self, b):
+            self._buf += b
+
+        def hexdigest(self):
+            return "ok"
+
+    def func(**kwargs):
+        calls["kwargs"] = kwargs
+        return Dummy()
+
+    hasher = Checksums.get_hasher(func)
+    assert isinstance(hasher, Dummy)
+    assert calls["kwargs"] == {"usedforsecurity": False}
+
+
+def test_get_hasher_type_error_thrown():
+    calls = {"with_kwargs": 0, "without_kwargs": 0}
+
+    class Dummy:
+        def __init__(self):
+            self._buf = b""
+
+        def update(self, b):
+            self._buf += b
+
+        def hexdigest(self):
+            return "ok"
+
+    def func(**kwargs):
+        if kwargs:
+            calls["with_kwargs"] += 1
+            raise TypeError("unexpected kwarg")
+        calls["without_kwargs"] += 1
+        return Dummy()
+
+    hasher = Checksums.get_hasher(func)
+    assert isinstance(hasher, Dummy)
+    assert calls["with_kwargs"] == 1
+    assert calls["without_kwargs"] == 1
+
+
 @responses.activate
 def test_deploy_artifact_with_checksum_success(mocker):
     responses.add(responses.PUT, f"{URL}/{ARTIFACT_PATH}", status=200)