Adding AIDL Service fuzzer for identity service

Test: m credstore_service_fuzzer && adb sync data && adb shell /data/fuzz/x86_64/credstore_service_fuzzer/credstore_service_fuzzer
Test: atest android.security.identity.cts
Bug: 232439428
Change-Id: I57494ad6a17e1a4a9dcb80d778edfd77a892790a

2 files changed, 94 insertions, 5 deletions

diff --git a/identity/Android.bp b/identity/Android.bp
index da0df076..007a3105 100644
--- a/identity/Android.bp
+++ b/identity/Android.bp
@@ -22,8 +22,8 @@ cc_defaults {
 
 }
 
-cc_binary {
-    name: "credstore",
+cc_defaults {
+    name: "credstore_defaults",
     defaults: [
         "identity_defaults",
         "identity_use_latest_hal_aidl_cpp_static",
@@ -31,7 +31,6 @@ cc_binary {
         "keymint_use_latest_hal_aidl_cpp_static",
         "android.hardware.identity-support-lib-deps",
     ],
-
     srcs: [
         "Credential.cpp",
         "CredentialData.cpp",
@@ -40,9 +39,7 @@ cc_binary {
         "Session.cpp",
         "Util.cpp",
         "WritableCredential.cpp",
-        "main.cpp",
     ],
-    init_rc: ["credstore.rc"],
     shared_libs: [
         "android.hardware.keymaster@4.0",
         "android.security.authorization-ndk",
@@ -68,6 +65,17 @@ cc_binary {
     ],
 }
 
+cc_binary {
+    name: "credstore",
+    defaults: [
+        "credstore_defaults",
+    ],
+    srcs: [
+        "main.cpp",
+    ],
+    init_rc: ["credstore.rc"],
+}
+
 filegroup {
     name: "credstore_aidl",
     srcs: [
@@ -112,3 +120,22 @@ cc_library_static {
         "libbinder",
     ],
 }
+
+cc_fuzz {
+    name: "credstore_service_fuzzer",
+    defaults: [
+        "credstore_defaults",
+        "service_fuzzer_defaults",
+        "fuzzer_disable_leaks",
+    ],
+    srcs: [
+        "fuzzers/credstore_service_fuzzer.cpp",
+    ],
+    fuzz_config: {
+        triage_assignee: "waghpawan@google.com",
+        cc: [
+            "trong@google.com",
+            "zeuthen@google.com",
+        ]
+    },
+}
diff --git a/identity/fuzzers/credstore_service_fuzzer.cpp b/identity/fuzzers/credstore_service_fuzzer.cpp
new file mode 100644
index 00000000..008cb0d8
--- /dev/null
+++ b/identity/fuzzers/credstore_service_fuzzer.cpp
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <android-base/logging.h>
+#include <fuzzbinder/libbinder_driver.h>
+#include <sys/stat.h>
+
+#include "CredentialStoreFactory.h"
+
+using android::security::identity::CredentialStoreFactory;
+using namespace android;
+
+void clearDirectory(const char* dirpath, bool recursive) {
+    DIR* dir = opendir(dirpath);
+    CHECK(dir != nullptr);
+    dirent* e;
+    struct stat s;
+    while ((e = readdir(dir)) != nullptr) {
+        if ((strcmp(e->d_name, ".") == 0) || (strcmp(e->d_name, "..") == 0)) {
+            continue;
+        }
+        std::string filename(dirpath);
+        filename.push_back('/');
+        filename.append(e->d_name);
+        int stat_result = lstat(filename.c_str(), &s);
+        CHECK_EQ(0, stat_result) << "unable to stat " << filename;
+        if (S_ISDIR(s.st_mode)) {
+            if (recursive) {
+                clearDirectory(filename.c_str(), true);
+                int rmdir_result = rmdir(filename.c_str());
+                CHECK_EQ(0, rmdir_result) << filename;
+            }
+        } else {
+            int unlink_result = unlink(filename.c_str());
+            CHECK_EQ(0, unlink_result) << filename;
+        }
+    }
+    closedir(dir);
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+    std::string dataDir = "/data/cred_store_fuzzer";
+    mkdir(dataDir.c_str(), 0700);
+    sp<CredentialStoreFactory> service = sp<CredentialStoreFactory>::make(dataDir);
+    fuzzService(service, FuzzedDataProvider(data, size));
+    clearDirectory(dataDir.c_str(), true);
+    rmdir(dataDir.c_str());
+    return 0;
+}