1 /*
2  * Copyright (C) 2019 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 
17 #include "patch_utils.h"
18 
19 #include <stdio.h>
20 
21 #include "adb_io.h"
22 #include "adb_utils.h"
23 #include "android-base/endian.h"
24 #include "sysdeps.h"
25 
26 #include "apk_archive.h"
27 
28 using namespace com::android;
29 using namespace com::android::fastdeploy;
30 using namespace android::base;
31 
32 static constexpr char kSignature[] = "FASTDEPLOY";
33 
34 APKMetaData PatchUtils::GetDeviceAPKMetaData(const APKDump& apk_dump) {
35     APKMetaData apkMetaData;
36     apkMetaData.set_absolute_path(apk_dump.absolute_path());
37 
38     std::string md5Hash;
39     int64_t localFileHeaderOffset;
40     int64_t dataSize;
41 
42     const auto& cd = apk_dump.cd();
43     auto cur = cd.data();
44     int64_t size = cd.size();
45     while (auto consumed = ApkArchive::ParseCentralDirectoryRecord(
46                    cur, size, &md5Hash, &localFileHeaderOffset, &dataSize)) {
47         cur += consumed;
48         size -= consumed;
49 
50         auto apkEntry = apkMetaData.add_entries();
51         apkEntry->set_md5(md5Hash);
52         apkEntry->set_dataoffset(localFileHeaderOffset);
53         apkEntry->set_datasize(dataSize);
54     }
55     return apkMetaData;
56 }
57 
58 APKMetaData PatchUtils::GetHostAPKMetaData(const char* apkPath) {
59     ApkArchive archive(apkPath);
60     auto dump = archive.ExtractMetadata();
61     if (dump.cd().empty()) {
62         fprintf(stderr, "adb: Could not extract Central Directory from %s\n", apkPath);
63         error_exit("Aborting");
64     }
65 
66     auto apkMetaData = GetDeviceAPKMetaData(dump);
67 
68     // Now let's set data sizes.
69     for (auto& apkEntry : *apkMetaData.mutable_entries()) {
70         auto dataSize =
71                 archive.CalculateLocalFileEntrySize(apkEntry.dataoffset(), apkEntry.datasize());
72         if (dataSize == 0) {
73             error_exit("Aborting");
74         }
75         apkEntry.set_datasize(dataSize);
76     }
77 
78     return apkMetaData;
79 }
80 
81 void PatchUtils::WriteSignature(borrowed_fd output) {
82     WriteFdExactly(output, kSignature, sizeof(kSignature) - 1);
83 }
84 
85 void PatchUtils::WriteLong(int64_t value, borrowed_fd output) {
86     int64_t littleEndian = htole64(value);
87     WriteFdExactly(output, &littleEndian, sizeof(littleEndian));
88 }
89 
90 void PatchUtils::WriteString(const std::string& value, android::base::borrowed_fd output) {
91     WriteLong(value.size(), output);
92     WriteFdExactly(output, value);
93 }
94 
95 void PatchUtils::Pipe(borrowed_fd input, borrowed_fd output, size_t amount) {
96     constexpr static size_t BUFFER_SIZE = 128 * 1024;
97     char buffer[BUFFER_SIZE];
98     size_t transferAmount = 0;
99     while (transferAmount != amount) {
100         auto chunkAmount = std::min(amount - transferAmount, BUFFER_SIZE);
101         auto readAmount = adb_read(input, buffer, chunkAmount);
102         if (readAmount < 0) {
103             fprintf(stderr, "adb: failed to read from input: %s\n", strerror(errno));
104             error_exit("Aborting");
105         }
106         WriteFdExactly(output, buffer, readAmount);
107         transferAmount += readAmount;
108     }
109 }
110