Factor out generic libfuzzer task (#2214)

src/agent/onefuzz-task/src/local/libfuzzer.rs

@@ -16,8 +16,8 @@ use crate::{
     },
     tasks::{
         analysis::generic::run as run_analysis, config::CommonConfig,
-        fuzz::libfuzzer_fuzz::LibFuzzerFuzzTask, regression::libfuzzer::LibFuzzerRegressionTask,
-        report::libfuzzer_report::ReportTask,
+        fuzz::libfuzzer::generic::LibFuzzerFuzzTask,
+        regression::libfuzzer::LibFuzzerRegressionTask, report::libfuzzer_report::ReportTask,
     },
 };
 #[cfg(any(target_os = "linux", target_os = "windows"))]

src/agent/onefuzz-task/src/local/libfuzzer_fuzz.rs

@@ -9,7 +9,7 @@ use crate::{
     },
     tasks::{
         config::CommonConfig,
-        fuzz::libfuzzer_fuzz::{Config, LibFuzzerFuzzTask},
+        fuzz::libfuzzer::generic::{Config, LibFuzzerFuzzTask},
     },
 };
 use anyhow::Result;
@@ -51,6 +51,7 @@ pub fn build_fuzz_config(
         check_fuzzer_help,
         expect_crash_on_failure,
         common,
+        extra: (),
     };
 
     Ok(config)

src/agent/onefuzz-task/src/tasks/config.rs

@@ -88,7 +88,7 @@ pub enum Config {
     DotnetCoverage(coverage::dotnet::Config),
 
     #[serde(alias = "libfuzzer_fuzz")]
-    LibFuzzerFuzz(fuzz::libfuzzer_fuzz::Config),
+    LibFuzzerFuzz(fuzz::libfuzzer::generic::Config),
 
     #[serde(alias = "libfuzzer_crash_report")]
     LibFuzzerReport(report::libfuzzer_report::Config),
@@ -225,7 +225,7 @@ impl Config {
                     .await
             }
             Config::LibFuzzerFuzz(config) => {
-                fuzz::libfuzzer_fuzz::LibFuzzerFuzzTask::new(config)?
+                fuzz::libfuzzer::generic::LibFuzzerFuzzTask::new(config)?
                     .run()
                     .await
             }

src/agent/onefuzz-task/src/tasks/fuzz/libfuzzer.rs

@@ -0,0 +1,5 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+pub mod common;
+pub mod generic;

src/agent/onefuzz-task/src/tasks/fuzz/libfuzzer/common.rs

@@ -40,8 +40,20 @@ pub fn default_workers() -> usize {
     usize::max(1, cpus - 1)
 }
 
+/// LibFuzzer subtypes that share custom configuration or process initialization.
+pub trait LibFuzzerType {
+    /// Extra configuration values expected by the `Config` for this type.
+    type Config;
+
+    /// Method that constructs a `LibFuzzer` configured as appropriate for the subtype.
+    ///
+    /// This may include things like setting special environment variables, or overriding
+    /// the defaults or values of some command arguments.
+    fn from_config(config: &Config<Self>) -> LibFuzzer;
+}
+
 #[derive(Debug, Deserialize, Clone)]
-pub struct Config {
+pub struct Config<L: LibFuzzerType + ?Sized> {
     pub inputs: SyncedDir,
     pub readonly_inputs: Option<Vec<SyncedDir>>,
     pub crashes: SyncedDir,
@@ -61,14 +73,23 @@ pub struct Config {
 
     #[serde(flatten)]
     pub common: CommonConfig,
+
+    #[serde(flatten)]
+    pub extra: L::Config,
 }
 
-pub struct LibFuzzerFuzzTask {
-    config: Config,
+pub struct LibFuzzerFuzzTask<L>
+where
+    L: LibFuzzerType,
+{
+    config: Config<L>,
 }
 
-impl LibFuzzerFuzzTask {
-    pub fn new(config: Config) -> Result<Self> {
+impl<L> LibFuzzerFuzzTask<L>
+where
+    L: LibFuzzerType,
+{
+    pub fn new(config: Config<L>) -> Result<Self> {
         Ok(Self { config })
     }
 
@@ -108,12 +129,8 @@ impl LibFuzzerFuzzTask {
             directories.append(&mut dirs);
         }
 
-        let fuzzer = LibFuzzer::new(
-            &self.config.target_exe,
-            &self.config.target_options,
-            &self.config.target_env,
-            &self.config.common.setup_dir,
-        );
+        let fuzzer = L::from_config(&self.config);
+
         fuzzer
             .verify(self.config.check_fuzzer_help, Some(directories))
             .await

src/agent/onefuzz-task/src/tasks/fuzz/libfuzzer/generic.rs

@@ -0,0 +1,29 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+use onefuzz::libfuzzer::LibFuzzer;
+
+use crate::tasks::fuzz::libfuzzer::common;
+
+/// Generic LibFuzzer with no special extra configuration.
+///
+/// Its configuration is fully controlled by the user, up to the constraints of the
+/// `LibFuzzer` wrapper itself.
+#[derive(Debug)]
+pub struct GenericLibFuzzer;
+
+impl common::LibFuzzerType for GenericLibFuzzer {
+    type Config = ();
+
+    fn from_config(config: &common::Config<Self>) -> LibFuzzer {
+        LibFuzzer::new(
+            &config.target_exe,
+            &config.target_options,
+            &config.target_env,
+            &config.common.setup_dir,
+        )
+    }
+}
+
+pub type Config = common::Config<GenericLibFuzzer>;
+pub type LibFuzzerFuzzTask = common::LibFuzzerFuzzTask<GenericLibFuzzer>;

src/agent/onefuzz-task/src/tasks/fuzz/mod.rs

@@ -2,5 +2,5 @@
 // Licensed under the MIT License.
 
 pub mod generator;
-pub mod libfuzzer_fuzz;
+pub mod libfuzzer;
 pub mod supervisor;