feat(starknet_os): verify syscall_ptr

crates/blockifier/src/execution/deprecated_syscalls/hint_processor.rs

@@ -103,6 +103,11 @@ use crate::transaction::objects::TransactionInfo;
 pub enum DeprecatedSyscallExecutionError {
     #[error("Bad syscall_ptr; expected: {expected_ptr:?}, got: {actual_ptr:?}.")]
     BadSyscallPointer { expected_ptr: Relocatable, actual_ptr: Relocatable },
+    #[error("Bad syscall selector; expected: {expected_selector:?}, got: {actual_selector:?}.")]
+    BadSyscallSelector {
+        expected_selector: DeprecatedSyscallSelector,
+        actual_selector: DeprecatedSyscallSelector,
+    },
     #[error(transparent)]
     EntryPointExecutionError(#[from] EntryPointExecutionError),
     #[error(transparent)]

crates/starknet_os/src/hint_processor/snos_deprecated_syscall_executor.rs

@@ -55,7 +55,6 @@ impl DeprecatedSyscallExecutor for DeprecatedSyscallHintProcessor {
                 actual_ptr,
             });
         }
-
         Ok(())
     }
 

crates/starknet_os/src/hints/error.rs

@@ -1,3 +1,4 @@
+use blockifier::execution::deprecated_syscalls::hint_processor::DeprecatedSyscallExecutionError;
 use blockifier::state::errors::StateError;
 use cairo_vm::hint_processor::hint_processor_definition::HintExtension;
 use cairo_vm::types::errors::math_errors::MathError;
@@ -39,6 +40,8 @@ pub enum OsHintError {
     BooleanIdExpected { id: Ids, felt: Felt },
     #[error("Failed to convert {variant:?} felt value {felt:?} to type {ty}: {reason:?}.")]
     ConstConversion { variant: Const, felt: Felt, ty: String, reason: String },
+    #[error(transparent)]
+    DeprecatedSyscallExecution(#[from] DeprecatedSyscallExecutionError),
     #[error("Tried to iterate past the end of {item_type}.")]
     EndOfIterator { item_type: String },
     #[error(transparent)]

crates/starknet_os/src/hints/hint_implementation/syscalls.rs

@@ -1,7 +1,12 @@
 use blockifier::execution::deprecated_syscalls::deprecated_syscall_executor::execute_next_deprecated_syscall;
+use blockifier::execution::deprecated_syscalls::hint_processor::DeprecatedSyscallExecutionError;
+use blockifier::execution::deprecated_syscalls::DeprecatedSyscallSelector;
+use blockifier::execution::execution_utils::felt_from_ptr;
 use blockifier::state::state_api::StateReader;
 use cairo_vm::hint_processor::builtin_hint_processor::hint_utils::get_ptr_from_var_name;
+use paste::paste;
 
+use crate::hints::error::OsHintError::DeprecatedSyscallExecution;
 use crate::hints::error::OsHintResult;
 use crate::hints::types::HintArgs;
 use crate::hints::vars::{Ids, Scope};
@@ -27,18 +32,38 @@ macro_rules! create_syscall_func {
     ($($name:ident),+) => {
         $(
             pub(crate) fn $name<S: StateReader>(
-                HintArgs { hint_processor, vm, ids_data, ap_tracking, exec_scopes, .. }: HintArgs<'_, '_, S>
+                HintArgs {
+                    hint_processor,
+                    vm,
+                    ids_data,
+                    ap_tracking,
+                    exec_scopes,
+                    ..
+                }: HintArgs<'_, '_, S>
             ) -> OsHintResult {
                 assert_eq!(
                     exec_scopes.get::<SyscallHandlerType>(Scope::SyscallHandlerType.into())?,
                     SyscallHandlerType::DeprecatedSyscallHandler
                 );
                 let syscall_hint_processor = &mut hint_processor.deprecated_syscall_hint_processor;
-                // TODO(Aner): need to verify that the correct syscall is being called (i.e.,
-                //   syscall_ptr matches the fn name). E.g., set syscall_ptr from fn name.
-                syscall_hint_processor.set_syscall_ptr(
-                    get_ptr_from_var_name(Ids::SyscallPtr.into(), vm, ids_data, ap_tracking)?
-                );
+                let syscall_ptr = get_ptr_from_var_name(
+                    Ids::SyscallPtr.into(), vm, ids_data, ap_tracking
+                )?;
+                let syscall_selector = DeprecatedSyscallSelector::try_from(
+                    vm.get_integer(syscall_ptr)?.into_owned()
+                )?;
+                let expected_selector = paste! { DeprecatedSyscallSelector::[<$name:camel>] };
+                if syscall_selector != expected_selector {
+                    return Err(
+                        DeprecatedSyscallExecution(
+                            DeprecatedSyscallExecutionError::BadSyscallSelector {
+                                expected_selector,
+                                actual_selector: syscall_selector,
+                            }
+                        )
+                    );
+                }
+                syscall_hint_processor.set_syscall_ptr(syscall_ptr);
                 Ok(
                     execute_next_deprecated_syscall(
                         syscall_hint_processor,