randomized blob generation and testing

src/kzg.rs

@@ -565,28 +565,27 @@ fn test_compute_kzg_proof_rand(){
     ).unwrap();
 
     let mut rng = rand::thread_rng();
-    let random_blob: Vec<u8> = (0..4095).map(|_| rng.gen_range(32..=126) as u8).collect();
-    let input = Blob::from_bytes_and_pad(&random_blob);
-    let input_poly = input.to_polynomial().unwrap();
-
-    for index in 0..10 {
-        // let index = rand::thread_rng().gen_range(0..input_poly.len());
+
+    for _ in 0..10 {
+
+        let blob_length = rand::thread_rng().gen_range(0..65000);
+        let random_blob: Vec<u8> = (0..blob_length).map(|_| rng.gen_range(32..=126) as u8).collect();
+        println!("generating blob of length is {}", blob_length);
+
+        let input = Blob::from_bytes_and_pad(&random_blob);
+        let input_poly = input.to_polynomial().unwrap();
         kzg.data_setup_custom(4, input.len().try_into().unwrap()).unwrap();
-        let mut rand_index = rand::thread_rng().gen_range(0..kzg.expanded_roots_of_unity.len());
-        loop {
-            if index == rand_index{
-                rand_index = rand::thread_rng().gen_range(0..kzg.expanded_roots_of_unity.len());
-            } else {
-                break;
-            }
-        }
+
+        let index = rand::thread_rng().gen_range(0..input_poly.get_length_of_padded_blob_as_fr_vector());
         let commitment = kzg.commit(&input_poly.clone()).unwrap();
         let proof = kzg.compute_kzg_proof_with_roots_of_unity(&input_poly, index.try_into().unwrap()).unwrap();
         let value_fr = input_poly.get_at_index(index).unwrap();
         let z_fr = kzg.get_nth_root_of_unity(index).unwrap();
         let pairing_result = kzg.verify_kzg_proof(commitment, proof, value_fr.clone(), z_fr.clone());
         assert_eq!(pairing_result, true);
-        assert_eq!(kzg.verify_kzg_proof(commitment, proof, value_fr.clone(), kzg.get_nth_root_of_unity(rand_index).unwrap().clone()), false)
+
+        // take random index, not the same index and check
+        assert_eq!(kzg.verify_kzg_proof(commitment, proof, value_fr.clone(), kzg.get_nth_root_of_unity((index+1)%input_poly.get_length_of_padded_blob_as_fr_vector()).unwrap().clone()), false)
     }
 }
 

src/polynomial.rs

@@ -26,6 +26,10 @@ impl Polynomial {
         Ok(Polynomial { elements: padded_input_fr, length_of_padded_blob, length_of_padded_blob_as_fr_vector: elements.len() })
     }
 
+    pub fn get_length_of_padded_blob_as_fr_vector(&self) -> usize {
+        self.length_of_padded_blob_as_fr_vector
+    }
+
     /// Returns the number of elements in the polynomial.
     pub fn len(&self) -> usize {
         self.elements.len()