1 /*
2 * Copyright (C) 2025 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 #include <stddef.h>
17 #include <stdint.h>
18 #include <unistd.h>
19
20 #include <string>
21 #include <vector>
22
23 #include <android-base/file.h>
24 #include <android-base/logging.h>
25 #include <android-base/parseint.h>
26 #include <bootloader_message/bootloader_message.h>
27 #include <cutils/android_reboot.h>
28
29 #include "reboot_utils.h"
30
31 namespace android {
32 namespace init {
33
RequestTradeInModeWipeIfNeeded()34 void RequestTradeInModeWipeIfNeeded() {
35 static constexpr const char* kWipeIndicator = "/metadata/tradeinmode/wipe";
36 static constexpr size_t kWipeAttempts = 3;
37
38 if (access(kWipeIndicator, R_OK) == -1) {
39 return;
40 }
41
42 // Write a counter to the wipe indicator, to try and prevent boot loops if
43 // recovery fails to wipe data.
44 uint32_t counter = 0;
45 std::string contents;
46 if (android::base::ReadFileToString(kWipeIndicator, &contents)) {
47 android::base::ParseUint(contents, &counter);
48 contents = std::to_string(++counter);
49 if (android::base::WriteStringToFile(contents, kWipeIndicator)) {
50 sync();
51 } else {
52 PLOG(ERROR) << "Failed to update " << kWipeIndicator;
53 }
54 } else {
55 PLOG(ERROR) << "Failed to read " << kWipeIndicator;
56 }
57
58 std::string err;
59 auto misc_device = get_misc_blk_device(&err);
60 if (misc_device.empty()) {
61 LOG(FATAL) << "Could not find misc device: " << err;
62 }
63
64 // If we've failed to wipe three times, don't include the wipe command. This
65 // will force us to boot into the recovery menu instead where a manual wipe
66 // can be attempted.
67 std::vector<std::string> options;
68 if (counter <= kWipeAttempts) {
69 options.emplace_back("--wipe_data");
70 options.emplace_back("--reason=tradeinmode");
71 }
72 if (!write_bootloader_message(options, &err)) {
73 LOG(FATAL) << "Could not issue wipe: " << err;
74 }
75 RebootSystem(ANDROID_RB_RESTART2, "recovery", "reboot,tradeinmode,wipe");
76 }
77
78 } // namespace init
79 } // namespace android
80