Merge pull request #935 from scrtlabs/analyze-code

AnalyzeCode functionality

cosmwasm/packages/sgx-vm/src/cache.rs

@@ -45,6 +45,12 @@ pub struct CosmCache<S: Storage + 'static, A: Api + 'static, Q: Querier + 'stati
     type_querier: PhantomData<Q>,
 }
 
+#[derive(PartialEq, Debug)]
+pub struct AnalysisReport {
+    pub has_ibc_entry_points: bool,
+    pub required_features: HashSet<String>,
+}
+
 impl<S, A, Q> CosmCache<S, A, Q>
 where
     S: Storage + 'static,
@@ -115,6 +121,39 @@ where
         }
     }
 
+    pub fn deserialize_wasm(wasm_code: &[u8]) -> VmResult<Module> {
+        deserialize_buffer(wasm_code).map_err(|err| {
+            VmError::static_validation_err(format!(
+                "Wasm bytecode could not be deserialized. Deserialization error: \"{}\"",
+                err
+            ))
+        })
+    }
+
+    /// Returns true if and only if all IBC entry points ([`REQUIRED_IBC_EXPORTS`])
+    /// exist as exported functions. This does not guarantee the entry points
+    /// are functional and for simplicity does not even check their signatures.
+    pub fn has_ibc_entry_points(module: &impl ExportInfo) -> bool {
+        let available_exports = module.exported_function_names(None);
+        REQUIRED_IBC_EXPORTS
+            .iter()
+            .all(|required| available_exports.contains(*required))
+    }
+
+    /// Performs static anlyzation on this Wasm without compiling or instantiating it.
+    ///
+    /// Once the contract was stored via [`save_wasm`], this can be called at any point in time.
+    /// It does not depend on any caching of the contract.
+    pub fn analyze(&self, checksum: &Checksum) -> VmResult<AnalysisReport> {
+        // Here we could use a streaming deserializer to slightly improve performance. However, this way it is DRYer.
+        let wasm = self.load_wasm(checksum)?;
+        let module = deserialize_wasm(&wasm)?;
+        Ok(AnalysisReport {
+            has_ibc_entry_points: has_ibc_entry_points(&module),
+            required_features: required_features_from_module(&module),
+        })
+    }
+
     /// Returns an Instance tied to a previously saved Wasm.
     /// Depending on availability, this is either generated from a cached instance, a cached module or Wasm code.
     pub fn get_instance(

go-cosmwasm/api/bindings.h

@@ -53,6 +53,22 @@ typedef struct Buffer {
   uintptr_t cap;
 } Buffer;
 
+/**
+ * The result type of the FFI function analyze_code.
+ *
+ * Please note that the unmanaged vector in `required_features`
+ * has to be destroyed exactly once. When calling `analyze_code`
+ * from Go this is done via `C.destroy_unmanaged_vector`.
+ */
+typedef struct AnalysisReport {
+  bool has_ibc_entry_points;
+  /**
+   * An UTF-8 encoded comma separated list of reqired features.
+   * This is never None/nil.
+   */
+  Buffer required_features;
+} AnalysisReport;
+
 typedef struct EnclaveRuntimeConfig {
   uint8_t module_cache_size;
 } EnclaveRuntimeConfig;
@@ -186,6 +202,10 @@ Buffer query(cache_t *cache,
              uint64_t *gas_used,
              Buffer *err);
 
+AnalysisReport analyze_code(cache_t *cache,
+                            ByteSliceView checksum,
+                            Buffer *error_msg);
+
 /**
  * frees a cache reference
  *

go-cosmwasm/api/lib.go

@@ -258,6 +258,25 @@ func Query(
 	return receiveVector(res), uint64(gasUsed), nil
 }
 
+func AnalyzeCode(
+	cache Cache,
+	codeHash []byte,
+) (*v1types.AnalysisReport, error) {
+	cs := sendSlice(codeHash)
+	defer runtime.KeepAlive(codeHash)
+	errMsg := C.Buffer{}
+	report, err := C.analyze_code(cache.ptr, cs, &errMsg)
+
+	if err != nil {
+		return nil, errorWithMessage(err, errMsg)
+	}
+	res := v1types.AnalysisReport{
+		HasIBCEntryPoints: bool(report.has_ibc_entry_points),
+		RequiredFeatures:  string(receiveVector(report.required_features)),
+	}
+	return &res, nil
+}
+
 // KeyGen Send KeyGen request to enclave
 func KeyGen() ([]byte, error) {
 	errmsg := C.Buffer{}
@@ -307,18 +326,3 @@ func errorWithMessage(err error, b C.Buffer) error {
 	}
 	return fmt.Errorf("%s", string(msg))
 }
-
-func AnalyzeCode(cache Cache, checksum []byte) (*v1types.AnalysisReport, error) {
-	cs := makeView(checksum)
-	defer runtime.KeepAlive(checksum)
-	errmsg := newUnmanagedVector(nil)
-	report, err := C.analyze_code(cache.ptr, cs, &errmsg)
-	if err != nil {
-		return nil, errorWithMessage(err, errmsg)
-	}
-	res := types.AnalysisReport{
-		HasIBCEntryPoints: bool(report.has_ibc_entry_points),
-		RequiredFeatures:  string(copyAndDestroyUnmanagedVector(report.required_features)),
-	}
-	return &res, nil
-}

go-cosmwasm/lib.go

@@ -236,41 +236,12 @@ func (w *Wasmer) Query(
 	return resp.Ok, gasUsed, nil
 }
 
-// AnalyzeCode will statically analyze the code.
+// AnalyzeCode returns a report of static analysis of the wasm contract (uncompiled).
+// This contract must have been stored in the cache previously (via Create).
+// Only info currently returned is if it exposes all ibc entry points, but this may grow later
 // Currently just reports if it exposes all IBC entry points.
 func (w *Wasmer) AnalyzeCode(
 	codeHash []byte,
 ) (*v1types.AnalysisReport, error) {
-	data, gasUsed, err := api.AnalyzeCode(codeHash)
-	if err != nil {
-		return nil, nil, gasUsed, err
-	}
-
-	key := data[0:64]
-	data = data[64:]
-
-	var respV010 v010types.InitResult
-	jsonErrV010 := json.Unmarshal(data, &respV010)
-
-	if jsonErrV010 == nil {
-		// v0.10 response
-		if respV010.Err != nil {
-			return nil, nil, gasUsed, fmt.Errorf("%v", respV010.Err)
-		}
-		return respV010.Ok, key, gasUsed, nil
-	}
-
-	var respV1 v1types.ContractResult
-	jsonErrV1 := json.Unmarshal(data, &respV1)
-
-	if jsonErrV1 == nil {
-		// v1 response
-		if respV1.Err != "" {
-			return nil, nil, gasUsed, fmt.Errorf(respV1.Err)
-		}
-		return respV1.Ok, key, gasUsed, nil
-	}
-
-	// unidentified response 🤷
-	return nil, nil, gasUsed, fmt.Errorf("cannot detect response type, v0.10: %v or v0.16: %v", jsonErrV010, jsonErrV1)
+	return api.AnalyzeCode(w.cache, codeHash)
 }

go-cosmwasm/src/lib.rs

@@ -499,6 +499,46 @@ fn do_query(
     Ok(res?)
 }
 
+/// The result type of the FFI function analyze_code.
+///
+/// Please note that the unmanaged vector in `required_features`
+/// has to be destroyed exactly once. When calling `analyze_code`
+/// from Go this is done via `C.destroy_unmanaged_vector`.
+#[repr(C)]
+#[derive(Copy, Clone, Default, Debug, PartialEq)]
+pub struct AnalysisReport {
+    pub has_ibc_entry_points: bool,
+    /// An UTF-8 encoded comma separated list of reqired features.
+    /// This is never None/nil.
+    pub required_features: Buffer,
+}
+
+#[no_mangle]
+pub extern "C" fn analyze_code(
+    cache: *mut cache_t,
+    checksum: ByteSliceView,
+    error_msg: Option<&mut Buffer>,
+) -> AnalysisReport {
+    let r = match to_cache(cache) {
+        Some(c) => catch_unwind(AssertUnwindSafe(move || do_analyze_code(c, checksum)))
+            .unwrap_or_else(|_| Err(Error::panic())),
+        None => Err(Error::unset_arg(CACHE_ARG)),
+    };
+    handle_c_error_default(r, error_msg)
+}
+
+fn do_analyze_code(
+    cache: &mut Cache<GoApi, GoStorage, GoQuerier>,
+    checksum: ByteSliceView,
+) -> Result<AnalysisReport, Error> {
+    let checksum: Checksum = checksum
+        .read()
+        .ok_or_else(|| Error::unset_arg(CHECKSUM_ARG))?
+        .try_into()?;
+    let report = cache.analyze(&checksum)?;
+    Ok(report.into())
+}
+
 #[no_mangle]
 pub extern "C" fn key_gen(err: Option<&mut Buffer>) -> Buffer {
     match untrusted_key_gen() {