Extend fuzzing for ctap1 and ctap2 requests

Previously, we only fuzzed the deserialization of
PublicKeyCredentialUserEntity.  This patch replaces that fuzz target
with the deserialization of entire ctap1 and ctap2 requests.

.github/workflows/ci.yml

@@ -38,6 +38,20 @@ jobs:
         cargo check --features get-info-full
         cargo check --features large-blobs
 
+  check-fuzz:
+    name: Check fuzz targets
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - uses: actions-rs/toolchain@v1
+      with:
+        profile: minimal
+        toolchain: nightly
+        override: true
+    - name: Check fuzz targets
+      run: |
+        cargo check --manifest-path fuzz/Cargo.toml
+
   test:
     name: Run tests
     runs-on: ubuntu-latest

fuzz/Cargo.toml

@@ -1,16 +1,15 @@
-
 [package]
 name = "ctap-types-fuzz"
 version = "0.0.0"
-authors = ["Automatically generated"]
 publish = false
-edition = "2018"
+edition = "2021"
 
 [package.metadata]
 cargo-fuzz = true
 
 [dependencies]
-libfuzzer-sys = "0.3"
+iso7816 = "0.1.2"
+libfuzzer-sys = "0.4"
 
 [dependencies.ctap-types]
 path = ".."
@@ -20,5 +19,15 @@ path = ".."
 members = ["."]
 
 [[bin]]
-name = "example"
-path = "fuzz_targets/example.rs"
+name = "ctap1"
+path = "fuzz_targets/ctap1.rs"
+test = false
+doc = false
+bench = false
+
+[[bin]]
+name = "ctap2"
+path = "fuzz_targets/ctap2.rs"
+test = false
+doc = false
+bench = false

fuzz/fuzz_targets/ctap1.rs

@@ -0,0 +1,11 @@
+#![no_main]
+
+use ctap_types::ctap1::Request;
+use iso7816::command::Command;
+use libfuzzer_sys::fuzz_target;
+
+fuzz_target!(|data: &[u8]| {
+    if let Ok(command) = Command::<7609>::try_from(data) {
+        Request::try_from(&command).ok();
+    }
+});

fuzz/fuzz_targets/ctap2.rs

@@ -0,0 +1,8 @@
+#![no_main]
+
+use ctap_types::ctap2::Request;
+use libfuzzer_sys::fuzz_target;
+
+fuzz_target!(|data: &[u8]| {
+    Request::deserialize(data).ok();
+});

fuzz/fuzz_targets/example.rs

@@ -1,10 +0,0 @@
-#![no_main]
-
-use libfuzzer_sys::fuzz_target;
-use ctap_types::serde::cbor_deserialize;
-
-fuzz_target!(|data: &[u8]| {
-    // fuzzed code goes here
-    type T = ctap_types::webauthn::PublicKeyCredentialUserEntity;
-    cbor_deserialize::<T>(&data).ok();
-});