fix: validate proof length during deserialization

ipa-multipoint/src/ipa.rs

@@ -27,8 +27,17 @@ impl IPAProof {
         let mut L_vec = Vec::with_capacity(num_points as usize);
         let mut R_vec = Vec::with_capacity(num_points as usize);
 
-        assert_eq!(((num_points * 2) + 1) * 32, bytes.len() as u32);
-        assert!(bytes.len().is_multiple_of(32));
+        let expected_len = ((num_points * 2) + 1) * 32;
+        if bytes.len() != expected_len as usize {
+            return Err(IOError::new(
+                IOErrorKind::InvalidData,
+                format!(
+                    "invalid proof length, expected {} bytes, got {} bytes",
+                    expected_len,
+                    bytes.len()
+                ),
+            ));
+        }
 
         // Chunk the byte slice into 32 bytes
         let mut chunks = bytes.chunks_exact(32);

ipa-multipoint/src/multiproof.rs

@@ -239,8 +239,15 @@ impl MultiPointProof {
     pub fn from_bytes(bytes: &[u8], poly_degree: usize) -> crate::IOResult<MultiPointProof> {
         use crate::{IOError, IOErrorKind};
 
+        if bytes.len() < 32 {
+            return Err(IOError::new(
+                IOErrorKind::InvalidData,
+                "bytes length is less than 32",
+            ));
+        }
+
         let g_x_comm_bytes = &bytes[0..32];
-        let ipa_bytes = &bytes[32..]; // TODO: we should return a Result here incase the user gives us bad bytes
+        let ipa_bytes = &bytes[32..];
         let point: Element = Element::from_bytes(g_x_comm_bytes.try_into().unwrap())
             .map_err(|_| IOError::from(IOErrorKind::InvalidData))?;
         let g_x_comm = point;
@@ -661,4 +668,12 @@ mod tests {
         }
         transcript.state
     }
+
+    #[test]
+    fn test_from_bytes_invalid_length() {
+        let bytes = [0u8; 31];
+        let result = MultiPointProof::from_bytes(&bytes, 256);
+        assert!(result.is_err());
+        assert_eq!(result.unwrap_err().kind(), std::io::ErrorKind::InvalidData);
+    }
 }