Use registers parsed from Ghidra on the Rust side.

Makefile

@@ -4,7 +4,6 @@ GHIDRA_PATH =
 all:
 	cargo build --release
 	mkdir -p ${HOME}/.config/cwe_checker
-	cp src/utils/registers.json ${HOME}/.config/cwe_checker/registers.json
 	cp src/config.json ${HOME}/.config/cwe_checker/config.json
 ifdef GHIDRA_PATH
 	cargo install --path caller --locked

cwe_checker_rs/src/analysis/pointer_inference/context/mod.rs

@@ -291,12 +291,13 @@ impl<'a> Context<'a> {
             new_state.clear_stack_parameter(extern_symbol, &self.project.stack_pointer_register),
             Some(&call.tid),
         );
+        let calling_conv = extern_symbol.get_calling_convention(&self.project);
         let mut possible_referenced_ids = BTreeSet::new();
         if extern_symbol.parameters.is_empty() && extern_symbol.return_values.is_empty() {
             // We assume here that we do not know the parameters and approximate them by all possible parameter registers.
             // This approximation is wrong if the function is known but has neither parameters nor return values.
             // We cannot distinguish these two cases yet.
-            for parameter_register_name in self.project.parameter_registers.iter() {
+            for parameter_register_name in calling_conv.parameter_register.iter() {
                 if let Some(register_value) = state.get_register_by_name(parameter_register_name) {
                     possible_referenced_ids.append(&mut register_value.referenced_ids());
                 }

cwe_checker_rs/src/analysis/pointer_inference/context/tests.rs

@@ -12,7 +12,7 @@ fn new_id(time: &str, reg_name: &str) -> AbstractIdentifier {
 }
 
 fn mock_extern_symbol(name: &str) -> ExternSymbol {
-    let arg = Arg::Register(register("RAX"));
+    let arg = Arg::Register(register("RDX"));
     ExternSymbol {
         tid: Tid::new("extern_".to_string() + name),
         name: name.into(),
@@ -80,13 +80,18 @@ fn mock_project() -> (Project, Config) {
         tid: Tid::new("program"),
         term: program,
     };
+    let cconv = CallingConvention {
+        name: "default".to_string(),
+        parameter_register: vec!["RDX".to_string()],
+        return_register: vec!["RDX".to_string()],
+        callee_saved_register: vec!["callee_saved_reg".to_string()],
+    };
     (
         Project {
             program: program_term,
             cpu_architecture: "x86_64".to_string(),
             stack_pointer_register: register("RSP"),
-            callee_saved_registers: vec!["callee_saved_reg".to_string()],
-            parameter_registers: vec!["RAX".to_string()],
+            calling_conventions: vec![cconv],
         },
         Config {
             allocation_symbols: vec!["malloc".into()],
@@ -186,9 +191,9 @@ fn context_problem_implementation() {
     let malloc = call_term("extern_malloc");
     let mut state_after_malloc = context.update_call_stub(&state, &malloc).unwrap();
     assert_eq!(
-        state_after_malloc.get_register(&register("RAX")).unwrap(),
+        state_after_malloc.get_register(&register("RDX")).unwrap(),
         Data::Pointer(PointerDomain::new(
-            new_id("call_extern_malloc", "RAX"),
+            new_id("call_extern_malloc", "RDX"),
             bv(0)
         ))
     );
@@ -214,7 +219,7 @@ fn context_problem_implementation() {
     state_after_malloc.set_register(
         &register("callee_saved_reg"),
         Data::Pointer(PointerDomain::new(
-            new_id("call_extern_malloc", "RAX"),
+            new_id("call_extern_malloc", "RDX"),
             bv(0),
         )),
     );
@@ -223,7 +228,7 @@ fn context_problem_implementation() {
         .update_call_stub(&state_after_malloc, &free)
         .unwrap();
     assert!(state_after_free
-        .get_register(&register("RAX"))
+        .get_register(&register("RDX"))
         .unwrap()
         .is_top());
     assert_eq!(state_after_free.memory.get_num_objects(), 2);
@@ -232,7 +237,7 @@ fn context_problem_implementation() {
             .get_register(&register("callee_saved_reg"))
             .unwrap(),
         Data::Pointer(PointerDomain::new(
-            new_id("call_extern_malloc", "RAX"),
+            new_id("call_extern_malloc", "RDX"),
             bv(0)
         ))
     );
@@ -304,7 +309,7 @@ fn update_return() {
         .ids_known_to_caller
         .insert(other_callsite_id.clone());
     state_before_return.set_register(
-        &register("RAX"),
+        &register("RDX"),
         Data::Pointer(PointerDomain::new(
             new_id("call_callee_other", "RSP"),
             bv(-32),

cwe_checker_rs/src/analysis/pointer_inference/context/trait_impls.rs

@@ -209,8 +209,10 @@ impl<'a> crate::analysis::interprocedural_fixpoint::Context<'a> for Context<'a>
             Jmp::CallInd { .. } => panic!("Indirect calls to extern symbols not yet supported."),
             _ => panic!("Malformed control flow graph encountered."),
         };
+        if let Some(extern_symbol) = self.extern_symbol_map.get(call_target) {
             // Clear non-callee-saved registers from the state.
-        new_state.clear_non_callee_saved_register(&self.project.callee_saved_registers[..]);
+            let cconv = extern_symbol.get_calling_convention(&self.project);
+            new_state.clear_non_callee_saved_register(&cconv.callee_saved_register[..]);
             // On x86, remove the return address from the stack (other architectures pass the return address in a register, not on the stack).
             // Note that in some calling conventions the callee also clears function parameters from the stack.
             // We do not detect and handle these cases yet.
@@ -228,7 +230,6 @@ impl<'a> crate::analysis::interprocedural_fixpoint::Context<'a> for Context<'a>
                 }
                 _ => new_state.set_register(stack_register, stack_pointer),
             }
-        if let Some(extern_symbol) = self.extern_symbol_map.get(call_target) {
             // Check parameter for possible use-after-frees
             self.check_parameter_register_for_dangling_pointer(state, call, extern_symbol);
 

cwe_checker_rs/src/intermediate_representation/term.rs

@@ -203,6 +203,19 @@ impl ExternSymbol {
             Err(anyhow!("Wrong number of parameter values"))
         }
     }
+
+    /// Get the calling convention corresponding to the extern symbol.
+    pub fn get_calling_convention<'a>(&self, project: &'a Project) -> &'a CallingConvention {
+        let cconv_name = match self.calling_convention {
+            Some(ref name) => name,
+            None => "default",
+        };
+        project
+            .calling_conventions
+            .iter()
+            .find(|cconv| cconv.name == cconv_name)
+            .unwrap()
+    }
 }
 
 /// The `Program` structure represents a disassembled binary.
@@ -230,6 +243,21 @@ impl Program {
     }
 }
 
+/// Calling convention related data
+#[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Hash, Clone)]
+pub struct CallingConvention {
+    /// The name of the calling convention
+    #[serde(rename = "calling_convention")]
+    pub name: String,
+    /// A list of possible parameter register
+    pub parameter_register: Vec<String>,
+    /// A list of possible return register
+    pub return_register: Vec<String>,
+    /// A list of callee-saved register,
+    /// i.e. the values of these registers should be the same after the call as they were before the call.
+    pub callee_saved_register: Vec<String>,
+}
+
 /// The `Project` struct is the main data structure representing a binary.
 ///
 /// It contains information about the disassembled binary
@@ -242,14 +270,8 @@ pub struct Project {
     pub cpu_architecture: String,
     /// The stack pointer register for the given CPU architecture.
     pub stack_pointer_register: Variable,
-    /// The names of callee-saved registers for the standard calling convention
-    /// for the given CPU architecture.
-    /// Note that this field may be removed in the future.
-    pub callee_saved_registers: Vec<String>,
-    /// The names of parameter registers for the standard calling convention
-    /// for the given CPU architecture.
-    /// Note that this field may be removed in the future.
-    pub parameter_registers: Vec<String>,
+    /// The known calling conventions that may be used for calls to extern functions.
+    pub calling_conventions: Vec<CallingConvention>,
 }
 
 impl Project {

cwe_checker_rs/src/pcode/term.rs

@@ -2,6 +2,7 @@ use super::{Expression, ExpressionType, Variable};
 use crate::intermediate_representation::Arg as IrArg;
 use crate::intermediate_representation::Blk as IrBlk;
 use crate::intermediate_representation::ByteSize;
+use crate::intermediate_representation::CallingConvention as IrCallingConvention;
 use crate::intermediate_representation::Def as IrDef;
 use crate::intermediate_representation::Expression as IrExpression;
 use crate::intermediate_representation::ExternSymbol as IrExternSymbol;
@@ -387,10 +388,32 @@ impl From<Program> for IrProgram {
 }
 
 #[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Hash, Clone)]
+pub struct CallingConvention {
+    #[serde(rename = "calling_convention")]
+    pub name: String,
+    parameter_register: Vec<String>,
+    return_register: Vec<String>,
+    unaffected_register: Vec<String>,
+    killed_by_call_register: Vec<String>,
+}
+
+impl From<CallingConvention> for IrCallingConvention {
+    fn from(cconv: CallingConvention) -> IrCallingConvention {
+        IrCallingConvention {
+            name: cconv.name,
+            parameter_register: cconv.parameter_register,
+            return_register: cconv.return_register,
+            callee_saved_register: cconv.unaffected_register,
+        }
+    }
+}
+
+#[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Hash, Clone)]
 pub struct Project {
     pub program: Term<Program>,
     pub cpu_architecture: String,
     pub stack_pointer_register: Variable,
+    pub register_calling_convention: Vec<CallingConvention>,
 }
 
 impl From<Project> for IrProject {
@@ -400,15 +423,15 @@ impl From<Project> for IrProject {
             tid: project.program.tid,
             term: project.program.term.into(),
         };
-        let (params, callee_saved) = crate::utils::get_generic_parameter_and_callee_saved_register(
-            &project.cpu_architecture,
-        );
         IrProject {
             program,
             cpu_architecture: project.cpu_architecture,
             stack_pointer_register: project.stack_pointer_register.into(),
-            callee_saved_registers: callee_saved,
-            parameter_registers: params,
+            calling_conventions: project
+                .register_calling_convention
+                .into_iter()
+                .map(|cconv| cconv.into())
+                .collect(),
         }
     }
 }
@@ -691,7 +714,16 @@ mod tests {
                 "size": 8,
                 "is_virtual": false
             },
-            "cpu_architecture": "x86_64"
+            "cpu_architecture": "x86_64",
+            "register_calling_convention": [
+                {
+                    "calling_convention": "default",
+                    "parameter_register": [],
+                    "return_register": [],
+                    "unaffected_register": [],
+                    "killed_by_call_register": []
+                }
+            ]
         }
         "#,
         )

cwe_checker_rs/src/term/mod.rs

 use crate::bil::*;
 use crate::intermediate_representation::Arg as IrArg;
 use crate::intermediate_representation::Blk as IrBlk;
+use crate::intermediate_representation::CallingConvention as IrCallingConvention;
 use crate::intermediate_representation::Def as IrDef;
 use crate::intermediate_representation::Expression as IrExpression;
 use crate::intermediate_representation::Jmp as IrJmp;
@@ -308,6 +309,7 @@ pub struct Project {
     pub stack_pointer_register: Variable,
     pub callee_saved_registers: Vec<String>,
     pub parameter_registers: Vec<String>,
+    pub return_registers: Vec<String>,
 }
 
 impl Project {
@@ -354,12 +356,17 @@ impl From<Project> for IrProject {
             tid: project.program.tid,
             term: project.program.term.into(),
         };
+        let default_cconv = IrCallingConvention {
+            name: "default".to_string(),
+            parameter_register: project.parameter_registers,
+            return_register: project.return_registers,
+            callee_saved_register: project.callee_saved_registers,
+        };
         IrProject {
             program,
             cpu_architecture: project.cpu_architecture,
             stack_pointer_register: project.stack_pointer_register.into(),
-            callee_saved_registers: project.callee_saved_registers,
-            parameter_registers: project.parameter_registers,
+            calling_conventions: vec![default_cconv],
         }
     }
 }

cwe_checker_rs/src/utils/mod.rs

 pub mod log;
 
-/// Get the names of parameter registers and callee saved registers
-/// of the standard calling convention for the given architecture.
-///
-/// The registers are read from a configuration file.
-pub fn get_generic_parameter_and_callee_saved_register(
-    cpu_architecture: &str,
-) -> (Vec<String>, Vec<String>) {
-    let project_dirs = directories::ProjectDirs::from("", "", "cwe_checker")
-        .expect("Could not discern location of configuration files.");
-    let config_dir = project_dirs.config_dir();
-    let register_config_path = config_dir.join("registers.json");
-    let file = std::fs::read_to_string(register_config_path)
-        .expect("Could not read register configuration file");
-    let mut registers_json: serde_json::Value = serde_json::from_str(&file).unwrap();
-    match cpu_architecture {
-        "x86" | "x86_32" => registers_json = registers_json["elf"]["x86"]["cdecl"].clone(),
-        "ARM_32" => registers_json = registers_json["elf"]["armv7"].clone(),
-        _ => registers_json = registers_json["elf"][cpu_architecture].clone(),
-    }
-    let mut callee_saved: Vec<String> =
-        serde_json::from_value(registers_json["callee_saved"].clone()).unwrap();
-    let mut callee_saved_float: Vec<String> =
-        serde_json::from_value(registers_json["float_callee_saved"].clone()).unwrap();
-    callee_saved.append(&mut callee_saved_float);
-    let mut params: Vec<String> = serde_json::from_value(registers_json["params"].clone()).unwrap();
-    let mut params_float: Vec<String> =
-        serde_json::from_value(registers_json["float_params"].clone()).unwrap();
-    params.append(&mut params_float);
-    (params, callee_saved)
-}
-
 /// Get the contents of a configuration file.
 pub fn read_config_file(filename: &str) -> serde_json::Value {
     let project_dirs = directories::ProjectDirs::from("", "", "cwe_checker")

ghidra/p_code_extractor/internal/ParseCspecContent.java

@@ -190,7 +190,6 @@ public class ParseCspecContent {
             XmlElement languageEnter = parser.peek();
             if(languageEnter.getAttribute("id").equals(languageId.getIdAsString())) {
                 cspecName = getCompilerName(parser);
-                break;
             } else {
                 discardSubTree(parser);
             }

src/utils/serde_json.ml

@@ -308,5 +308,6 @@ let of_project (project: Project.t) (extern_symbols: extern_symbol List.t) (entr
     ("cpu_architecture", build_string (Arch.to_string (Project.arch project)));
     ("stack_pointer_register", of_var (Symbol_utils.stack_register project));
     ("callee_saved_registers", build_array (List.map (Cconv.get_register_list project "callee_saved") ~f:(fun reg_name -> build_string reg_name) ));
-    ("parameter_registers", build_array (List.map (Cconv.get_register_list project "params") ~f:(fun reg_name -> build_string reg_name) ))
+    ("parameter_registers", build_array (List.map (Cconv.get_register_list project "params") ~f:(fun reg_name -> build_string reg_name) ));
+    ("return_registers", build_array (List.map (Cconv.get_register_list project "return") ~f:(fun reg_name -> build_string reg_name) ))
   ]