Fix: oer enumerated de handled zero padding when it should not (libra…

…sn#249)
koxu1996 · May 13, 2024 · 9e889ba · 9e889ba
1 parent 9476bae
commit 9e889ba
Show file tree

Hide file tree

Showing 2 changed files with 19 additions and 4 deletions.
diff --git a/src/oer.rs b/src/oer.rs
@@ -93,11 +93,26 @@ mod tests {
             A = 1,
             B = 2,
         }
+        #[derive(AsnType, Decode, Encode, Debug, Clone, Copy, PartialEq)]
+        #[rasn(enumerated)]
+        enum TestDefaults {
+            A,
+            B,
+        }
         // Leading zeroes
         decode_error!(coer, Test, &[0x00, 0x00, 0x00, 0x01, 0x01]);
-        decode_ok!(oer, Test, &[0x00, 0x00, 0x00, 0x01, 0x01], Test::A);
+        // Leading zeros not allowed for enumerated values in any case
+        round_trip!(oer, Test, Test::A, &[0x01]);
+        round_trip!(oer, TestDefaults, TestDefaults::A, &[0x00]);
+        // Unfortunately, below is correct since we just parse the first byte and do not chek the
+        // remainder in reality
+        decode_ok!(oer, TestDefaults, &[0x00, 0x00], TestDefaults::A);
+        decode_error!(oer, Test, &[0x00, 0x01]);
+        decode_error!(oer, Test, &[0x00, 0x81, 0x01]);
+        decode_ok!(oer, Test, &[0x81, 0x01], Test::A);
+        decode_ok!(oer, Test, &[0x01], Test::A);
         // Long form when not needed
-        decode_error!(coer, Test, &[0b1000_0001, 0x01, 0x01]);
-        decode_ok!(oer, Test, &[0b1000_0001, 0x01, 0x01], Test::A);
+        decode_error!(coer, Test, &[0b1000_0001, 0x01]);
+        decode_ok!(oer, Test, &[0b1000_0001, 0x01], Test::A);
     }
 }
diff --git a/src/oer/de.rs b/src/oer/de.rs
@@ -497,7 +497,7 @@ impl<'input> crate::Decoder for Decoder<'input> {
     }
 
     fn decode_enumerated<E: Enumerated>(&mut self, _: Tag) -> Result<E, Self::Error> {
-        let byte = self.parse_byte_and_leading_zeros()?;
+        let byte = self.parse_one_byte()?;
         if byte < 128 {
             // Short form, use value directly as unsigned integer
             E::from_discriminant(isize::from(byte))