Fix more bls v4 issue

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "milagro-bls-binding"
-version = "1.4.0"
+version = "1.5.0"
 edition = "2018"
 authors = ["[email protected]"]
 

src/lib.rs

@@ -7,6 +7,16 @@ use pyo3::wrap_pyfunction;
 
 use milagro_bls::{AggregatePublicKey, AggregateSignature, PublicKey, SecretKey, Signature};
 
+fn is_zilch(w: &[u8]) -> bool {
+    for i in 0..32 {
+        if w[i] != 0 {
+            return false;
+        }
+    }
+    true
+}
+
+
 #[pyfunction]
 fn SkToPk(_py: Python, SK: &PyBytes) -> PyResult<PyObject> {
     let sk_bytes: Vec<u8> = SK.extract()?;
@@ -19,6 +29,9 @@ fn SkToPk(_py: Python, SK: &PyBytes) -> PyResult<PyObject> {
 #[pyfunction]
 fn Sign(_py: Python, SK: &PyBytes, message: &PyBytes) -> PyResult<PyObject> {
     let sk_bytes: Vec<u8> = SK.extract()?;
+    if is_zilch(&sk_bytes) {
+        return Err(PyErr::new::<ValueError, _>("Zero key"));
+    }
     let msg_bytes: Vec<u8> = message.extract()?;
     let sk = SecretKey::from_bytes(&sk_bytes)
         .map_err(|e| PyErr::new::<ValueError, _>(format!("Bad key: {:?}", e)))?;
@@ -104,7 +117,13 @@ fn FastAggregateVerify(
             Err(_) => return false,
         };
         match PublicKey::from_bytes(pubkey_bytes) {
-            Ok(_pk) => pks.push(_pk),
+            Ok(_pk) => {
+                if _pk.key_validate() {
+                    pks.push(_pk);
+                } else {
+                    return false;
+                }
+            },
             Err(_) => return false,
         };
     }

test.py

@@ -59,14 +59,6 @@ def test_sign_verify(privkey_int):
     assert bls.Verify(pub, msg, sig)
 
 
-def test_sign_verify_zero():
-    privkey = to_bytes(0)
-    msg = "foooooo".encode('utf-8')
-    pub = bls.SkToPk(privkey)
-    sig = bls.Sign(privkey, msg)
-    assert not bls.Verify(pub, msg, sig)
-
-
 @pytest.mark.parametrize(
     'signature_points,result_point',
     [
@@ -94,6 +86,11 @@ def test_fast_aggregate_verify(SKs, message):
 
 
 def test_weird_cases():
-    bad_signature = b'\x00' * 96
-    assert not bls.AggregateVerify([], [], bad_signature)
-    assert bls.Aggregate([]) == b'\xc0' + b'\x00' * 95
+    Z1_PUBKEY = b'\xc0' + b'\x00' * 47
+    Z2_SIGNATURE = b'\xc0' + b'\x00' * 95
+    assert not bls.AggregateVerify([], [], Z2_SIGNATURE)
+    assert bls.Aggregate([]) == Z2_SIGNATURE
+    with pytest.raises(ValueError , match=r"Zero*"):
+        bls.Sign(to_bytes(0), b'abcd')
+    assert not bls.Verify(Z1_PUBKEY, b'abcd', Z2_SIGNATURE)
+    assert not bls.FastAggregateVerify([Z1_PUBKEY], b'abcd', Z2_SIGNATURE)