xref: /aosp_15_r20/system/apex/apexd/apexd_vendor_apex.cpp (revision 33f3758387333dbd2962d7edbd98681940d895da)
1 /*
2  * Copyright (C) 2023 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  * This file contains the vendor-apex-specific functions of apexd
17  */
18 
19 #include "apexd_vendor_apex.h"
20 
21 #include <android-base/logging.h>
22 #include <android-base/strings.h>
23 #include <vintf/VintfObject.h>
24 
25 #include "apex_file_repository.h"
26 #include "apexd_private.h"
27 #include "apexd_utils.h"
28 
29 using android::base::Error;
30 using android::base::Result;
31 using android::base::StartsWith;
32 
33 namespace android::apex {
34 
35 using apexd_private::GetActiveMountPoint;
36 
HasVintfIn(std::span<const std::string> apex_mounts)37 static Result<bool> HasVintfIn(std::span<const std::string> apex_mounts) {
38   for (const auto& mount : apex_mounts) {
39     if (OR_RETURN(PathExists(mount + "/etc/vintf"))) return true;
40   }
41   return false;
42 }
43 
44 // Checks Compatibility for incoming APEXes.
45 //    Adds the data from apex's vintf_fragment(s) and tests compatibility.
CheckVintf(std::span<const ApexFile> apex_files,std::span<const std::string> mount_points)46 Result<std::map<std::string, std::vector<std::string>>> CheckVintf(
47     std::span<const ApexFile> apex_files,
48     std::span<const std::string> mount_points) {
49   std::string error;
50 
51   std::vector<std::string> current_mounts;
52   for (const auto& apex : apex_files) {
53     current_mounts.push_back(GetActiveMountPoint(apex.GetManifest()));
54   }
55 
56   // Skip the check unless any of the current/incoming APEXes has etc/vintf.
57   if (!OR_RETURN(HasVintfIn(current_mounts)) &&
58       !OR_RETURN(HasVintfIn(mount_points))) {
59     return {};
60   }
61 
62   // Create PathReplacingFileSystem instance containing caller's path
63   // substitutions
64   std::map<std::string, std::string> replacements;
65   CHECK(apex_files.size() == mount_points.size()) << "size mismatch";
66   for (size_t i = 0; i < current_mounts.size(); i++) {
67     replacements.emplace(current_mounts[i], mount_points[i]);
68   }
69   std::unique_ptr<vintf::FileSystem> path_replaced_fs =
70       std::make_unique<vintf::details::PathReplacingFileSystem>(
71           std::make_unique<vintf::details::FileSystemImpl>(),
72           std::move(replacements));
73 
74   // Create a new VintfObject that uses our path-replacing FileSystem instance
75   auto vintf_object = vintf::VintfObject::Builder()
76                           .setFileSystem(std::move(path_replaced_fs))
77                           .build();
78 
79   // Disable RuntimeInfo components. Allows callers to run check
80   // without requiring read permission of restricted resources
81   auto flags = vintf::CheckFlags::DEFAULT;
82   flags = flags.disableRuntimeInfo();
83 
84   // checkCompatibility on vintfObj using the replacement vintf directory
85   int ret = vintf_object->checkCompatibility(&error, flags);
86   if (ret == vintf::INCOMPATIBLE) {
87     return Error() << "CheckVintf failed: not compatible. error=" << error;
88   }
89   if (ret != vintf::COMPATIBLE) {
90     return Error() << "CheckVintf failed: error=" << error;
91   }
92 
93   // Compat check passed.
94   // Collect HAL information from incoming APEXes for metrics.
95   std::map<std::string, std::vector<std::string>> apex_hals;
96   auto collect_hals = [&](auto manifest) {
97     manifest->forEachInstance([&](const auto& instance) {
98       if (instance.updatableViaApex().has_value()) {
99         apex_hals[instance.updatableViaApex().value()].push_back(
100             instance.nameWithVersion());
101       }
102       return true;  // continue
103     });
104   };
105   collect_hals(vintf_object->getFrameworkHalManifest());
106   collect_hals(vintf_object->getDeviceHalManifest());
107 
108   return apex_hals;
109 }
110 
111 }  // namespace android::apex
112