feat(wasm-builder): Check all gear requirements for code at compile time

utils/wasm-builder/src/checks.rs

@@ -0,0 +1,48 @@
+use gear_wasm_instrument::parity_wasm::elements::{Internal, Module, Type};
+
+#[derive(Debug)]
+pub enum Error {
+    ExportSectionMissing,
+    ImportSectionMissing,
+    FunctionSectionMissing,
+    TypeSectionMissing,
+    CodeSectionMissing,
+    UnexpectedFunctionExport(String),
+    MissingEntryFunction,
+    InvalidExportFunctionSignature,
+}
+
+pub fn do_checks(module: Module) -> Result<(), Error> {
+
+    let exports = module.export_section().ok_or(Error::ExportSectionMissing)?;
+    let imports = module.import_section().ok_or(Error::ImportSectionMissing)?;
+    let functions = module.function_section().ok_or(Error::FunctionSectionMissing)?;
+    let types = module.type_section().ok_or(Error::TypeSectionMissing)?;
+    let code = module.code_section().ok_or(Error::CodeSectionMissing)?;
+
+    let imported_functions = imports.functions();
+
+    // While this is checked in Code::new, we might as well check it when building wasm program
+    let mut entry = false;
+    for e in exports.entries() {
+        if let Internal::Function(i) = e.internal() {
+            match e.field() {
+                "init" | "handle" | "handle_reply" | "handle_signal" | "state" | "meta" => {
+                    entry = true;
+                    let Type::Function(ref t) = types.types()[functions.entries()[*i as usize - imported_functions]];
+                    if !t.params().is_empty() || !t.results().is_empty() {
+                        return Err(Error::InvalidExportFunctionSignature);
+                    }
+                },
+                _ => return Err(Error::UnexpectedFunctionExport(e.field().to_string()))
+            }
+        }
+    }
+    if !entry {
+        return Err(Error::MissingEntryFunction)
+    }
+
+
+
+    Ok(())
+}

utils/wasm-builder/src/lib.rs

@@ -36,6 +36,7 @@ pub mod optimize;
 mod smart_fs;
 mod stack_end;
 mod wasm_project;
+mod checks;
 
 pub const TARGET: &str = env!("TARGET");
 

utils/wasm-builder/src/wasm_project.rs

@@ -30,6 +30,8 @@ use std::{
     path::{Path, PathBuf},
 };
 use toml::value::Table;
+use crate::checks::do_checks;
+use crate::optimize::do_optimization;
 
 const OPT_LEVEL: &str = "z";
 
@@ -371,6 +373,10 @@ extern "C" fn metahash() {{
                 .context("Failed to write optimized WASM binary")?;
         }
 
+        // Generate module from optimized wasm file to run gear checks
+        let module = parity_wasm::elements::Module::from_bytes(fs::read(opt_wasm_path.clone()).expect("Failed to read optimized wasm binary")).expect("Invalid wasm generated by wasm-opt");
+        do_checks(module).expect("Wasm code did not pass gear checks");
+
         // Create path string in `.binpath` file.
         let relative_path_to_wasm = pathdiff::diff_paths(&self.wasm_target_dir, &self.original_dir)
             .with_context(|| {