trusty: Apploader fuzzer

Bug: 181630912
Test: trusty_apploader_tipc_fuzzer
Test: trusty_apploader_app_fuzzer
Change-Id: I1cc2329ca2a4e983f6ded45810d4c34e1433c5b0

trusty/apploader/fuzz/Android.bp

@@ -0,0 +1,40 @@
+// Copyright (C) 2021 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.
+
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+// Fuzz Trusty IPC messages sent to apploader.
+cc_fuzz {
+    name: "trusty_apploader_tipc_fuzzer",
+    defaults: ["trusty_fuzzer_defaults"],
+    srcs: [":trusty_tipc_fuzzer"],
+    cflags: [
+        "-DTRUSTY_APP_PORT=\"com.android.trusty.apploader\"",
+        "-DTRUSTY_APP_UUID=\"081ba88f-f1ee-452e-b5e8-a7e9ef173a97\"",
+        "-DTRUSTY_APP_FILENAME=\"apploader.syms.elf\"",
+    ]
+}
+
+// Fuzz app package sent to apploader.
+cc_fuzz {
+    name: "trusty_apploader_app_fuzzer",
+    defaults: ["trusty_fuzzer_defaults"],
+    srcs: ["app_fuzzer.cpp"],
+    include_dirs: ["system/core/trusty/apploader"],
+    shared_libs: [
+        "libdmabufheap",
+    ],
+}

trusty/apploader/fuzz/app_fuzzer.cpp

@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2021 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 <BufferAllocator/BufferAllocator.h>
+#include <android-base/unique_fd.h>
+#include <apploader_ipc.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <trusty/coverage/coverage.h>
+#include <trusty/fuzz/counters.h>
+#include <trusty/fuzz/utils.h>
+#include <trusty/tipc.h>
+#include <unistd.h>
+#include <iostream>
+
+using android::base::unique_fd;
+using android::trusty::coverage::CoverageRecord;
+using android::trusty::fuzz::ExtraCounters;
+using android::trusty::fuzz::TrustyApp;
+
+#define TIPC_DEV "/dev/trusty-ipc-dev0"
+#define APPLOADER_PORT "com.android.trusty.apploader"
+#define APPLOADER_MODULE_NAME "apploader.syms.elf"
+
+/* Apploader TA's UUID is 081ba88f-f1ee-452e-b5e8-a7e9ef173a97 */
+static struct uuid apploader_uuid = {
+        0x081ba88f,
+        0xf1ee,
+        0x452e,
+        {0xb5, 0xe8, 0xa7, 0xe9, 0xef, 0x17, 0x3a, 0x97},
+};
+
+static inline uintptr_t RoundPageUp(uintptr_t val) {
+    return (val + (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
+}
+
+static bool SendLoadMsg(int chan, int dma_buf, size_t dma_buf_size) {
+    apploader_header hdr = {
+            .cmd = APPLOADER_CMD_LOAD_APPLICATION,
+    };
+    apploader_load_app_req req = {
+            .package_size = static_cast<uint64_t>(dma_buf_size),
+    };
+    iovec iov[] = {
+            {
+                    .iov_base = &hdr,
+                    .iov_len = sizeof(hdr),
+            },
+            {
+                    .iov_base = &req,
+                    .iov_len = sizeof(req),
+            },
+    };
+    trusty_shm shm = {
+            .fd = dma_buf,
+            .transfer = TRUSTY_SHARE,
+    };
+
+    int rc = tipc_send(chan, iov, 2, &shm, 1);
+    if (rc != static_cast<int>(sizeof(hdr) + sizeof(req))) {
+        std::cerr << "Failed to send request" << std::endl;
+        return false;
+    }
+
+    apploader_resp resp;
+    rc = read(chan, &resp, sizeof(resp));
+    if (rc != static_cast<int>(sizeof(resp))) {
+        std::cerr << "Failed to receive response" << std::endl;
+        return false;
+    }
+
+    return true;
+}
+
+static CoverageRecord record(TIPC_DEV, &apploader_uuid, APPLOADER_MODULE_NAME);
+
+extern "C" int LLVMFuzzerInitialize(int* /* argc */, char*** /* argv */) {
+    auto ret = record.Open();
+    if (!ret.ok()) {
+        std::cerr << ret.error() << std::endl;
+        exit(-1);
+    }
+    return 0;
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+    ExtraCounters counters(&record);
+    counters.Reset();
+
+    android::trusty::fuzz::TrustyApp ta(TIPC_DEV, APPLOADER_PORT);
+    auto ret = ta.Connect();
+    if (!ret.ok()) {
+        std::cerr << ret.error() << std::endl;
+        android::trusty::fuzz::Abort();
+    }
+
+    uint64_t shm_len = size ? RoundPageUp(size) : PAGE_SIZE;
+    BufferAllocator alloc;
+    unique_fd dma_buf(alloc.Alloc(kDmabufSystemHeapName, shm_len));
+    if (dma_buf < 0) {
+        std::cerr << "Failed to create dmabuf of size: " << shm_len << std::endl;
+        android::trusty::fuzz::Abort();
+    }
+
+    void* shm_base = mmap(0, shm_len, PROT_READ | PROT_WRITE, MAP_SHARED, dma_buf, 0);
+    if (shm_base == MAP_FAILED) {
+        std::cerr << "Failed to mmap() dmabuf" << std::endl;
+        android::trusty::fuzz::Abort();
+    }
+
+    memcpy(shm_base, data, size);
+
+    bool success = SendLoadMsg(*ta.GetRawFd(), dma_buf, shm_len);
+    if (!success) {
+        std::cerr << "Failed to send load message" << std::endl;
+        android::trusty::fuzz::Abort();
+    }
+
+    munmap(shm_base, shm_len);
+    return 0;
+}