validator: fixed minor encoding/decoding bugs

src/runtime/import/util.rs

@@ -311,7 +311,7 @@ pub(crate) fn get_last_block_info(mut ctx: FunctionEnvMut<Env>) -> i64 {
 
     // Create the return object
     let mut ret = Vec::with_capacity(8 + 32 + blake3::OUT_LEN);
-    ret.extend_from_slice(&block.header.height.to_be_bytes());
+    ret.extend_from_slice(&darkfi_serial::serialize(&block.header.height));
     ret.extend_from_slice(&block.header.nonce.to_repr());
     ret.extend_from_slice(block.header.previous.as_bytes());
 

src/validator/utils.rs

@@ -124,7 +124,7 @@ pub async fn block_rank(block: &BlockInfo, previous_previous: &BlockInfo) -> Res
     let data = &tx.calls[0].data.data;
     let mut decoder = Cursor::new(&data);
     // PoW uses MoneyPoWRewardParamsV1
-    decoder.set_position(563);
+    decoder.set_position(499);
     let vrf_proof: VrfProof = AsyncDecodable::decode_async(&mut decoder).await?;
 
     // Compute VRF u64