feat: declare post compilation builtin validation (#296)

crates/gateway/Cargo.toml

@@ -18,6 +18,7 @@ blockifier= { workspace = true , features = ["testing"] }
 cairo-lang-starknet-classes.workspace = true
 cairo-vm.workspace = true
 hyper.workspace = true
+lazy_static.workspace = true
 papyrus_config.workspace = true
 papyrus_rpc.workspace = true
 reqwest.workspace = true

crates/gateway/src/errors.rs

@@ -23,7 +23,7 @@ pub enum GatewayError {
     CompilationError(#[from] CompilationUtilError),
     #[error(
         "The supplied compiled class hash {supplied:?} does not match the hash of the Casm class \
-         compiled from the supplied Sierra {hash_result:?}."
+         compiled from the supplied Sierra {hash_result:?}"
     )]
     CompiledClassHashMismatch { supplied: CompiledClassHash, hash_result: CompiledClassHash },
     #[error(transparent)]
@@ -38,6 +38,8 @@ pub enum GatewayError {
     StatefulTransactionValidatorError(#[from] StatefulTransactionValidatorError),
     #[error(transparent)]
     StatelessTransactionValidatorError(#[from] StatelessTransactionValidatorError),
+    #[error("{builtins:?} is not a subsquence of {supported_builtins:?}")]
+    UnsupportedBuiltins { builtins: Vec<String>, supported_builtins: Vec<String> },
 }
 
 impl IntoResponse for GatewayError {

crates/gateway/src/gateway.rs

@@ -9,6 +9,10 @@ use axum::routing::{get, post};
 use axum::{Json, Router};
 use blockifier::execution::contract_class::{ClassInfo, ContractClass, ContractClassV1};
 use blockifier::execution::execution_utils::felt_to_stark_felt;
+use cairo_lang_starknet_classes::casm_contract_class::{
+    CasmContractClass, CasmContractEntryPoints,
+};
+use lazy_static::lazy_static;
 use starknet_api::core::CompiledClassHash;
 use starknet_api::rpc_transaction::{RPCDeclareTransaction, RPCTransaction};
 use starknet_api::transaction::TransactionHash;
@@ -25,7 +29,7 @@ use crate::rpc_state_reader::RpcStateReaderFactory;
 use crate::state_reader::StateReaderFactory;
 use crate::stateful_transaction_validator::StatefulTransactionValidator;
 use crate::stateless_transaction_validator::StatelessTransactionValidator;
-use crate::utils::{external_tx_to_thin_tx, get_sender_address};
+use crate::utils::{external_tx_to_thin_tx, get_sender_address, is_subsequence};
 
 #[cfg(test)]
 #[path = "gateway_test.rs"]
@@ -161,6 +165,7 @@ pub fn compile_contract_class(declare_tx: &RPCDeclareTransaction) -> GatewayResu
             return Err(GatewayError::CompilationError(CompilationUtilError::CompilationPanic));
         }
     };
+    validate_casm_class(&casm_contract_class)?;
 
     let hash_result =
         CompiledClassHash(felt_to_stark_felt(&casm_contract_class.compiled_class_hash()));
@@ -199,3 +204,33 @@ impl ComponentRunner for Gateway {
         Ok(())
     }
 }
+
+// TODO(Arni): Add to a config.
+// TODO(Arni): Use the Builtin enum from Starknet-api, and explicitly tag each builtin as supported
+// or unsupported so that the compiler would alert us on new builtins.
+lazy_static! {
+    static ref SUPPORTED_BUILTINS: Vec<String> = {
+        // The OS expects this order for the builtins.
+        const SUPPORTED_BUILTIN_NAMES: [&str; 7] =
+            ["pedersen", "range_check", "ecdsa", "bitwise", "ec_op", "poseidon", "segment_arena"];
+        SUPPORTED_BUILTIN_NAMES.iter().map(|builtin| builtin.to_string()).collect::<Vec<String>>()
+    };
+}
+
+// TODO(Arni): Add test.
+fn validate_casm_class(contract_class: &CasmContractClass) -> Result<(), GatewayError> {
+    let CasmContractEntryPoints { external, l1_handler, constructor } =
+        &contract_class.entry_points_by_type;
+    let entry_points_iterator = external.iter().chain(l1_handler.iter()).chain(constructor.iter());
+
+    for entry_point in entry_points_iterator {
+        let builtins = &entry_point.builtins;
+        if !is_subsequence(builtins, &SUPPORTED_BUILTINS) {
+            return Err(GatewayError::UnsupportedBuiltins {
+                builtins: builtins.clone(),
+                supported_builtins: SUPPORTED_BUILTINS.to_vec(),
+            });
+        }
+    }
+    Ok(())
+}

crates/gateway/src/utils.rs

@@ -17,6 +17,10 @@ use starknet_mempool_types::mempool_types::ThinTransaction;
 
 use crate::errors::StatefulTransactionValidatorResult;
 
+#[cfg(test)]
+#[path = "utils_test.rs"]
+mod utils_test;
+
 macro_rules! implement_ref_getters {
     ($(($member_name:ident, $member_type:ty));* $(;)?) => {
         $(fn $member_name(&self) -> &$member_type {
@@ -155,3 +159,20 @@ pub fn get_tx_hash(tx: &AccountTransaction) -> TransactionHash {
         AccountTransaction::Invoke(tx) => tx.tx_hash,
     }
 }
+
+/// Checks whether 'subsequence' is a subsequence of 'sequence'.
+pub fn is_subsequence<T: Eq>(subsequence: &[T], sequence: &[T]) -> bool {
+    let mut offset = 0;
+
+    for item in sequence {
+        if offset == subsequence.len() {
+            return true;
+        }
+
+        if item == &subsequence[offset] {
+            offset += 1;
+        }
+    }
+
+    offset == subsequence.len()
+}

crates/gateway/src/utils_test.rs

@@ -0,0 +1,78 @@
+use pretty_assertions::assert_eq;
+use rstest::rstest;
+
+use crate::utils::is_subsequence;
+
+#[rstest]
+#[case::empty(
+    &[],
+    &[],
+    true
+)]
+#[case::empty_subsequence(
+    &[],
+    &["a", "b"],
+    true
+)]
+#[case::empty_sequence(
+    &["a"],
+    &[],
+    false
+)]
+#[case::subsequence_1(
+    &["a"],
+    &["a", "b", "c"],
+    true
+)]
+#[case::subsequence_2(
+    &["b"],
+    &["a", "b", "c"],
+    true
+)]
+#[case::subsequence_3(
+    &["c"],
+    &["a", "b", "c"],
+    true
+)]
+#[case::subsequence_4(
+    &["a", "b"],
+    &["a", "b", "c"],
+    true
+)]
+#[case::subsequence_5(
+    &["a", "c"],
+    &["a", "b", "c"],
+    true
+)]
+#[case::subsequence_6(
+    &["b", "c"],
+    &["a", "b", "c"],
+    true
+)]
+#[case::subsequence_7(
+    &["a", "b", "c"],
+    &["a", "b", "c"],
+    true
+)]
+#[case::out_of_order_1(
+    &["b", "a"],
+    &["a", "b", "c"],
+    false
+)]
+#[case::out_of_order_2(
+    &["b", "a", "c"],
+    &["a", "b", "c"],
+    false
+)]
+#[case::unrelated(
+    &["a", "b", "d"],
+    &["a", "b", "c"],
+    false
+)]
+fn test_is_subsequence(
+    #[case] subsequence: &[&str],
+    #[case] sequence: &[&str],
+    #[case] expected_result: bool,
+) {
+    assert_eq!(is_subsequence(subsequence, sequence), expected_result);
+}