WIP: feat(starknet_os): verify syscall_ptr

Author: aner-starkware

Cargo.lock

@@ -171,6 +171,7 @@ chrono = "0.4.26"
 clap = "4.5.4"
 colored = "3"
 const_format = "0.2.30"
+convert_case = "0.8.0"
 criterion = "0.5.1"
 deadqueue = "0.2.4"
 defaultmap = "0.5.0"

Cargo.toml

@@ -333,7 +333,7 @@ pub fn validate_run(
     }
 
     // Validate syscall segment end.
-    syscall_handler.verify_syscall_ptr(syscall_end_ptr).map_err(|_| {
+    syscall_handler.verify_syscall_ptr(&mut runner.vm, syscall_end_ptr).map_err(|_| {
         PostExecutionError::SecurityValidationError("Syscall segment end".to_string())
     })?;
 

crates/blockifier/src/execution/deprecated_entry_point_execution.rs

@@ -59,7 +59,11 @@ pub trait DeprecatedSyscallExecutor {
 
     fn increment_syscall_count(&mut self, selector: &DeprecatedSyscallSelector);
 
-    fn verify_syscall_ptr(&self, actual_ptr: Relocatable) -> DeprecatedSyscallResult<()>;
+    fn verify_syscall_ptr(
+        &self,
+        vm: &mut VirtualMachine,
+        actual_ptr: Relocatable,
+    ) -> DeprecatedSyscallResult<()>;
 
     fn get_mut_syscall_ptr(&mut self) -> &mut Relocatable;
 
@@ -284,11 +288,9 @@ pub fn execute_next_deprecated_syscall<T: DeprecatedSyscallExecutor>(
     ap_tracking: &ApTracking,
 ) -> HintExecutionResult {
     let initial_syscall_ptr = get_ptr_from_var_name("syscall_ptr", vm, ids_data, ap_tracking)?;
-    deprecated_syscall_executor.verify_syscall_ptr(initial_syscall_ptr)?;
+    deprecated_syscall_executor.verify_syscall_ptr(vm, initial_syscall_ptr)?;
 
-    let selector = DeprecatedSyscallSelector::try_from(
-        deprecated_syscall_executor.read_next_syscall_selector(vm)?,
-    )?;
+    let selector = deprecated_syscall_executor.read_next_syscall_selector(vm)?.try_into()?;
     deprecated_syscall_executor.increment_syscall_count(&selector);
 
     execute_deprecated_syscall_from_selector(deprecated_syscall_executor, vm, selector)

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

@@ -442,7 +442,11 @@ impl HintProcessorLogic for DeprecatedSyscallHintProcessor<'_> {
 }
 
 impl DeprecatedSyscallExecutor for DeprecatedSyscallHintProcessor<'_> {
-    fn verify_syscall_ptr(&self, actual_ptr: Relocatable) -> DeprecatedSyscallResult<()> {
+    fn verify_syscall_ptr(
+        &self,
+        _vm: &mut VirtualMachine,
+        actual_ptr: Relocatable,
+    ) -> DeprecatedSyscallResult<()> {
         if actual_ptr != self.syscall_ptr {
             return Err(DeprecatedSyscallExecutionError::BadSyscallPointer {
                 expected_ptr: self.syscall_ptr,

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

@@ -32,6 +32,7 @@ cairo-vm = { workspace = true, features = [
   "cairo-0-secp-hints",
   "extensive_hints",
 ] }
+convert_case = "0.8.0"
 derive_more.workspace = true
 indexmap.workspace = true
 indoc.workspace = true

crates/starknet_os/Cargo.toml

@@ -38,6 +38,7 @@ use blockifier::execution::deprecated_syscalls::{
 };
 use cairo_vm::types::relocatable::Relocatable;
 use cairo_vm::vm::vm_core::VirtualMachine;
+use starknet_types_core::felt::FromStrError;
 
 use super::snos_hint_processor::DeprecatedSyscallHintProcessor;
 
@@ -47,14 +48,23 @@ impl DeprecatedSyscallExecutor for DeprecatedSyscallHintProcessor {
         todo!()
     }
 
-    fn verify_syscall_ptr(&self, actual_ptr: Relocatable) -> DeprecatedSyscallResult<()> {
+    fn verify_syscall_ptr(
+        &self,
+        vm: &mut VirtualMachine,
+        actual_ptr: Relocatable,
+    ) -> DeprecatedSyscallResult<()> {
         let expected_ptr = self.syscall_ptr.expect("Syscall must be set at this point.");
         if actual_ptr != expected_ptr {
             return Err(DeprecatedSyscallExecutionError::BadSyscallPointer {
                 expected_ptr,
                 actual_ptr,
             });
         }
+        if !self.syscall_matches_name(vm.get_integer(actual_ptr)?.into_owned()) {
+            // TODO(Aner): Create a new error type for this case.
+            // TODO(Aner): Add a test for this case.
+            return Err(DeprecatedSyscallExecutionError::FromStr(FromStrError {}));
+        };
 
         Ok(())
     }

crates/starknet_os/src/hint_processor/snos_deprecated_syscall_executor.rs

@@ -351,16 +351,35 @@ impl SyscallHintProcessor {
 
 pub struct DeprecatedSyscallHintProcessor {
     pub(crate) syscall_ptr: Option<Relocatable>,
+    pub(crate) syscall_name: Option<String>,
 }
 
 // TODO(Dori): remove this #[allow] after the constructor is no longer trivial.
 #[allow(clippy::new_without_default)]
 impl DeprecatedSyscallHintProcessor {
     pub fn new() -> Self {
-        Self { syscall_ptr: None }
+        Self { syscall_ptr: None, syscall_name: None }
     }
 
     pub fn set_syscall_ptr(&mut self, syscall_ptr: Relocatable) {
         self.syscall_ptr = Some(syscall_ptr);
     }
+
+    pub fn set_syscall_name(&mut self, syscall_name: String) {
+        self.syscall_name = Some(syscall_name);
+    }
+
+    // TODO(Aner): test this function.
+    pub(crate) fn syscall_matches_name(&self, syscall_raw_selector: Felt) -> bool {
+        if let Some(syscall_name) = &self.syscall_name {
+            // Remove leading zero bytes from selector.
+            let selector_bytes = syscall_raw_selector.to_bytes_be();
+            let first_non_zero =
+                selector_bytes.iter().position(|&byte| byte != b'\0').unwrap_or(32);
+
+            syscall_name.as_bytes() == &selector_bytes[first_non_zero..]
+        } else {
+            false
+        }
+    }
 }

crates/starknet_os/src/hint_processor/snos_hint_processor.rs

@@ -1,6 +1,7 @@
 use blockifier::execution::deprecated_syscalls::deprecated_syscall_executor::execute_next_deprecated_syscall;
 use blockifier::state::state_api::StateReader;
 use cairo_vm::hint_processor::builtin_hint_processor::hint_utils::get_ptr_from_var_name;
+use convert_case::{Case, Casing};
 
 use crate::hints::error::OsHintResult;
 use crate::hints::types::HintArgs;
@@ -34,8 +35,9 @@ macro_rules! create_syscall_func {
                     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_name(
+                    stringify!($name).to_string().to_case(Case::Pascal)
+                );
                 syscall_hint_processor.set_syscall_ptr(
                     get_ptr_from_var_name(Ids::SyscallPtr.into(), vm, ids_data, ap_tracking)?
                 );