feat(block validation): ledger

Author: cong-or

rust/immutable-ledger/src/validate.rs

@@ -2,11 +2,89 @@
 //!
 //! Facilitates validation for immutable ledger
 
-use crate::serialize::EncodedBlock;
+use crate::serialize::blake3;
+use anyhow::Ok;
 
-/// Validate block
-pub fn validate_block(_current_block: EncodedBlock, _previous_block: EncodedBlock) -> bool {
-    todo!()
+use crate::serialize::{blake2b_512, decode_block, EncodedBlock, HashFunction};
+
+/// Validate current block against previous block.
+pub fn validate_block(
+    current_block: EncodedBlock, previous_block: EncodedBlock, hasher: HashFunction,
+) -> anyhow::Result<()> {
+    let current_block = decode_block(current_block)?;
+
+    let hashed_previous_block = match hasher {
+        HashFunction::Blake3 => blake3(&previous_block)?.to_vec(),
+        HashFunction::Blake2b => blake2b_512(&previous_block)?.to_vec(),
+    };
+    let previous_block = decode_block(previous_block)?;
+
+    // chain_id MUST be the same as for the previous block (except for genesis).
+    if current_block.0 .0 != previous_block.0 .0 {
+        return Err(anyhow::anyhow!(
+            "Module: Immutable ledger,  Message: Chain_id MUST be NOT the same as for the previous block {:?} {:?}",
+            current_block.0 .0,
+            previous_block.0 .0
+        ));
+    };
+
+    // height MUST be incremented by 1 from the previous block height value (except for genesis and final block).
+    // Genesis block MUST have 0 value. Final block MUST hash be incremented by 1 from the previous block height
+    // and changed the sign to negative. E.g. previous block height is 9 and the Final block height is -10.
+    if current_block.0 .1 .0 != previous_block.0 .1 .0 + 1 {
+        return Err(anyhow::anyhow!(
+            "Module: Immutable ledger,  Message: height validation failed: {:?} {:?}",
+            current_block.0 .1 .0,
+            previous_block.0 .1 .0
+        ));
+    }
+
+    // timestamp MUST be greater or equals than the timestamp of the previous block (except for genesis)
+    if current_block.0 .2 .0 <= previous_block.0 .2 .0 {
+        return Err(anyhow::anyhow!(
+            "Module: Immutable ledger,  Message: timestamp validation failed: {:?} {:?}",
+            current_block.0 .2 .0,
+            previous_block.0 .2 .0
+        ));
+    }
+
+    // prev_block_id MUST be a hash of the previous block bytes (except for genesis).
+    if current_block.0 .3 .0 != hashed_previous_block {
+        return Err(anyhow::anyhow!(
+            "Module: Immutable ledger,  Message: previous hash validation failed: {:?} {:?}",
+            current_block.0 .3 .0,
+            previous_block.0 .3 .0
+        ));
+    }
+
+    // ledger_type MUST be the same as for the previous block if present (except for genesis).
+    if current_block.0 .4 .0 != previous_block.0 .4 .0 {
+        return Err(anyhow::anyhow!(
+            "Module: Immutable ledger,  Message: ledger type validation failed: {:?} {:?}",
+            current_block.0 .4 .0,
+            previous_block.0 .4 .0
+        ));
+    }
+
+    // purpose_id MUST be the same as for the previous block if present (except for genesis).
+    if current_block.0 .5 .0 != previous_block.0 .5 .0 {
+        return Err(anyhow::anyhow!(
+            "Module: Immutable ledger,  Message: purpose id validation failed: {:?} {:?}",
+            current_block.0 .5 .0,
+            previous_block.0 .5 .0
+        ));
+    }
+
+    // validator MUST be the same as for the previous block if present (except for genesis)
+    if current_block.0 .6 .0 != previous_block.0 .6 .0 {
+        return Err(anyhow::anyhow!(
+            "Module: Immutable ledger,  Message: validator validation failed: {:?} {:?}",
+            current_block.0 .6 .0,
+            previous_block.0 .6 .0
+        ));
+    }
+
+    Ok(())
 }
 
 #[cfg(test)]
@@ -18,8 +96,8 @@ mod tests {
     use uuid::Uuid;
 
     use crate::serialize::{
-        encode_block, encode_block_header, BlockTimeStamp, ChainId, EncodedBlockData, Height, Kid,
-        LedgerType, Metadata, PreviousBlockHash, PurposeId, Validator, ValidatorKeys,
+        blake2b_512, encode_block, encode_block_header, BlockTimeStamp, ChainId, EncodedBlockData,
+        Height, Kid, LedgerType, Metadata, PreviousBlockHash, PurposeId, Validator, ValidatorKeys,
     };
 
     use crate::serialize::HashFunction::Blake2b;
@@ -29,7 +107,7 @@ mod tests {
     #[test]
     fn validate_block_test() {
         //
-        // CURRENT BLOCK
+        // PREVIOUS BLOCK
         //
         //
         let kid_a: [u8; 16] = hex::decode("00112233445566778899aabbccddeeff")
@@ -82,7 +160,7 @@ mod tests {
 
         block_data.bytes(block_data_bytes).unwrap();
 
-        let current_block = encode_block(
+        let previous_block = encode_block(
             encoded_block_hdr.clone(),
             EncodedBlockData(block_data_bytes.to_vec()),
             ValidatorKeys(vec![validator_secret_key_bytes, validator_secret_key_bytes]),
@@ -91,60 +169,30 @@ mod tests {
         .unwrap();
 
         //
-        // PREVIOUS B
-        //
+        // CURRENT BLOCK
         //
-        let kid_a: [u8; 16] = hex::decode("00112233445566778899aabbccddeeff")
-            .unwrap()
-            .try_into()
-            .unwrap();
 
-        let kid_b: [u8; 16] = hex::decode("00112233445566778899aabbccddeeff")
-            .unwrap()
-            .try_into()
-            .unwrap();
-
-        let chain_id = ChainId(Ulid::new());
-        let block_height = Height(5);
-        let block_ts = BlockTimeStamp(1728474515);
-        let prev_block_height = PreviousBlockHash(vec![0; 64]);
-        let ledger_type = LedgerType(Uuid::new_v4());
-        let purpose_id = PurposeId(Ulid::new());
+        let block_height = Height(6);
+        let block_ts = BlockTimeStamp(1728474518);
+        let prev_block_hash = PreviousBlockHash(blake2b_512(&previous_block).unwrap().to_vec());
         let validators = Validator(vec![Kid(kid_a), Kid(kid_b)]);
         let metadata = Some(Metadata(vec![1; 128]));
 
         let encoded_block_hdr = encode_block_header(
             chain_id,
             block_height,
             block_ts,
-            prev_block_height.clone(),
+            prev_block_hash,
             ledger_type.clone(),
             purpose_id.clone(),
             validators.clone(),
             metadata.clone(),
         )
         .unwrap();
 
-        // validators
-        let validator_secret_key_bytes: [u8; SECRET_KEY_LENGTH] = [
-            157, 097, 177, 157, 239, 253, 090, 096, 186, 132, 074, 244, 146, 236, 044, 196, 068,
-            073, 197, 105, 123, 050, 105, 025, 112, 059, 172, 003, 028, 174, 127, 096,
-        ];
-
-        let out: Vec<u8> = Vec::new();
-        let mut block_data = minicbor::Encoder::new(out);
-
-        let block_data_bytes = &[
-            157, 097, 177, 157, 239, 253, 090, 096, 186, 132, 074, 244, 146, 236, 044, 196, 157,
-            239, 253, 090, 096, 186, 132, 074, 244, 146, 236, 044, 196, 157, 239, 253, 090, 096,
-            186, 132, 074, 244, 146, 236, 044, 196, 157, 239, 253, 090, 096, 186, 132, 074, 244,
-            146, 236, 044, 196, 157, 239, 253, 090, 096, 186, 132, 074, 244, 146, 236, 044, 196,
-            157,
-        ];
-
         block_data.bytes(block_data_bytes).unwrap();
 
-        let previous_block = encode_block(
+        let current_block = encode_block(
             encoded_block_hdr.clone(),
             EncodedBlockData(block_data_bytes.to_vec()),
             ValidatorKeys(vec![validator_secret_key_bytes, validator_secret_key_bytes]),
@@ -156,6 +204,9 @@ mod tests {
         // VALIDATE BLOCK
         //
 
-        validate_block(current_block, previous_block);
+        match validate_block(current_block, previous_block, Blake2b) {
+            Ok(_) => (),
+            Err(err) => panic!("Block validation failed: {:?}", err),
+        };
     }
 }