Cope with invalid hash algorithms in RECORD

- raise an InvalidRecordEntry
- catch such things during wheel validation and include them in the
  issues reported

Author: dimbleby

src/installer/records.py

@@ -175,13 +175,15 @@ def from_elements(cls, path: str, hash_: str, size: str) -> "RecordEntry":
         if not path:
             issues.append("`path` cannot be empty")
 
+        hash_value: Optional[Hash] = None
         if hash_:
             try:
-                hash_value: Optional[Hash] = Hash.parse(hash_)
+                hash_value = Hash.parse(hash_)
+                if hash_value.name not in hashlib.algorithms_available:
+                    issues.append(f"invalid hash algorithm '{hash_value.name}'")
+                    hash_value = None
             except ValueError:
                 issues.append("`hash` does not follow the required format")
-        else:
-            hash_value = None
 
         if size:
             try:

src/installer/sources.py

@@ -8,7 +8,7 @@
 from typing import BinaryIO, ClassVar, Iterator, List, Optional, Tuple, Type, cast
 
 from installer.exceptions import InstallerError
-from installer.records import RecordEntry, parse_record_file
+from installer.records import InvalidRecordEntry, RecordEntry, parse_record_file
 from installer.utils import canonicalize_name, parse_wheel_filename
 
 WheelContentElement = Tuple[Tuple[str, str, str], BinaryIO, bool]
@@ -271,7 +271,15 @@ def validate_record(self, *, validate_contents: bool = True) -> None:
                 )
                 continue
 
-            record = RecordEntry.from_elements(*record_args)
+            try:
+                record = RecordEntry.from_elements(*record_args)
+            except InvalidRecordEntry as e:
+                for issue in e.issues:
+                    issues.append(
+                        f"In {self._zipfile.filename}, entry in RECORD file for "
+                        f"{item.filename} is invalid: {issue}"
+                    )
+                continue
 
             if item.filename == f"{self.dist_info_dir}/RECORD":
                 # Assert that RECORD doesn't have size and hash.

tests/test_sources.py

@@ -325,3 +325,24 @@ def test_rejects_record_validation_failed(self, fancy_wheel):
                 match="hash / size of (.+) didn't match RECORD",
             ):
                 source.validate_record()
+
+    def test_rejects_record_containing_unknown_hash(self, fancy_wheel):
+        with WheelFile.open(fancy_wheel) as source:
+            record_file_contents = source.read_dist_info("RECORD")
+
+        new_record_file_contents = record_file_contents.replace("sha256=", "sha=")
+        replace_file_in_zip(
+            fancy_wheel,
+            filename="fancy-1.0.0.dist-info/RECORD",
+            content=new_record_file_contents,
+        )
+
+        with WheelFile.open(fancy_wheel) as source:
+            with pytest.raises(
+                WheelFile.validation_error,
+                match=(
+                    "In .+, entry in RECORD file for .+ is invalid: "
+                    "invalid hash algorithm 'sha'"
+                ),
+            ):
+                source.validate_record(validate_contents=True)