1 /*
2  * Copyright (C) 2017 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 
18 #define LOG_TAG "libvintf"
19 #include <android-base/logging.h>
20 #include <android-base/strings.h>
21 
22 #include "RuntimeInfo.h"
23 
24 #include "CompatibilityMatrix.h"
25 #include "KernelConfigParser.h"
26 #include "parse_string.h"
27 
28 #include <dirent.h>
29 #include <errno.h>
30 #include <sys/utsname.h>
31 #include <unistd.h>
32 
33 #include <fstream>
34 #include <iostream>
35 #include <sstream>
36 
37 #include <android-base/properties.h>
38 #include <selinux/selinux.h>
39 #include <zlib.h>
40 
41 #define PROC_CONFIG "/proc/config.gz"
42 #define BUFFER_SIZE sysconf(_SC_PAGESIZE)
43 
44 static constexpr char kMainline[] = "-mainline-";
45 
46 namespace android {
47 namespace vintf {
48 
49 struct RuntimeInfoFetcher {
RuntimeInfoFetcherandroid::vintf::RuntimeInfoFetcher50     RuntimeInfoFetcher(RuntimeInfo *ki) : mRuntimeInfo(ki) { }
51     status_t fetchAllInformation(RuntimeInfo::FetchFlags flags);
52 
53    private:
54     status_t fetchVersion(RuntimeInfo::FetchFlags flags);
55     status_t fetchKernelConfigs(RuntimeInfo::FetchFlags flags);
56     status_t fetchCpuInfo(RuntimeInfo::FetchFlags flags);
57     status_t fetchKernelSepolicyVers(RuntimeInfo::FetchFlags flags);
58     status_t fetchAvb(RuntimeInfo::FetchFlags flags);
59     status_t parseKernelVersion();
60     RuntimeInfo *mRuntimeInfo;
61     KernelConfigParser mConfigParser;
62 };
63 
64 // decompress /proc/config.gz and read its contents.
fetchKernelConfigs(RuntimeInfo::FetchFlags)65 status_t RuntimeInfoFetcher::fetchKernelConfigs(RuntimeInfo::FetchFlags) {
66     gzFile f = gzopen(PROC_CONFIG, "rb");
67     if (f == NULL) {
68         LOG(ERROR) << "Could not open /proc/config.gz: " << errno;
69         return -errno;
70     }
71 
72     char buf[BUFFER_SIZE];
73     int len;
74     while ((len = gzread(f, buf, sizeof buf)) > 0) {
75         mConfigParser.process(buf, len);
76     }
77     status_t err = OK;
78     if (len < 0) {
79         int errnum;
80         const char *errmsg = gzerror(f, &errnum);
81         LOG(ERROR) << "Could not read /proc/config.gz: " << errmsg;
82         err = (errnum == Z_ERRNO ? -errno : errnum);
83     }
84     mConfigParser.finish();
85     gzclose(f);
86     mRuntimeInfo->mKernel.mConfigs = std::move(mConfigParser.configs());
87     return err;
88 }
89 
fetchCpuInfo(RuntimeInfo::FetchFlags)90 status_t RuntimeInfoFetcher::fetchCpuInfo(RuntimeInfo::FetchFlags) {
91     // TODO implement this; 32-bit and 64-bit has different format.
92     std::ifstream in{"/proc/cpuinfo"};
93     if (!in.is_open()) {
94         LOG(WARNING) << "Cannot read /proc/cpuinfo";
95         return UNKNOWN_ERROR;
96     }
97     std::stringstream sstream;
98     sstream << in.rdbuf();
99     mRuntimeInfo->mCpuInfo = sstream.str();
100     return OK;
101 }
102 
fetchKernelSepolicyVers(RuntimeInfo::FetchFlags)103 status_t RuntimeInfoFetcher::fetchKernelSepolicyVers(RuntimeInfo::FetchFlags) {
104     int pv;
105 #ifdef LIBVINTF_TARGET
106     pv = security_policyvers();
107 #else
108     pv = 0;
109 #endif
110     if (pv < 0) {
111         return pv;
112     }
113     mRuntimeInfo->mKernelSepolicyVersion = pv;
114     return OK;
115 }
116 
fetchVersion(RuntimeInfo::FetchFlags flags)117 status_t RuntimeInfoFetcher::fetchVersion(RuntimeInfo::FetchFlags flags) {
118     struct utsname buf;
119     if (uname(&buf)) {
120         return -errno;
121     }
122     mRuntimeInfo->mOsName = buf.sysname;
123     mRuntimeInfo->mNodeName = buf.nodename;
124     mRuntimeInfo->mOsRelease = buf.release;
125     mRuntimeInfo->mOsVersion = buf.version;
126     mRuntimeInfo->mHardwareId = buf.machine;
127 
128     mRuntimeInfo->mIsMainline = mRuntimeInfo->mOsRelease.find(kMainline) != std::string::npos;
129 
130     status_t err = RuntimeInfo::parseGkiKernelRelease(flags, mRuntimeInfo->mOsRelease,
131                                                       &mRuntimeInfo->mKernel.mVersion,
132                                                       &mRuntimeInfo->mKernel.mLevel);
133     if (err == OK) return OK;
134 
135     err = parseKernelVersion();
136     if (err != OK) {
137         LOG(ERROR) << "Could not parse kernel version from \""
138                    << mRuntimeInfo->mOsRelease << "\"";
139     }
140     return err;
141 }
142 
parseKernelVersion()143 status_t RuntimeInfoFetcher::parseKernelVersion() {
144     auto pos = mRuntimeInfo->mOsRelease.find('.');
145     if (pos == std::string::npos) {
146         return UNKNOWN_ERROR;
147     }
148     pos = mRuntimeInfo->mOsRelease.find('.', pos + 1);
149     if (pos == std::string::npos) {
150         return UNKNOWN_ERROR;
151     }
152     pos = mRuntimeInfo->mOsRelease.find_first_not_of("0123456789", pos + 1);
153     // no need to check pos == std::string::npos, because substr will handle this
154     if (!parse(mRuntimeInfo->mOsRelease.substr(0, pos), &mRuntimeInfo->mKernel.mVersion)) {
155         return UNKNOWN_ERROR;
156     }
157     return OK;
158 }
159 
fetchAvb(RuntimeInfo::FetchFlags)160 status_t RuntimeInfoFetcher::fetchAvb(RuntimeInfo::FetchFlags) {
161     std::string prop = android::base::GetProperty("ro.boot.vbmeta.avb_version", "0.0");
162     if (!parse(prop, &mRuntimeInfo->mBootVbmetaAvbVersion)) {
163         return UNKNOWN_ERROR;
164     }
165     prop = android::base::GetProperty("ro.boot.avb_version", "0.0");
166     if (!parse(prop, &mRuntimeInfo->mBootAvbVersion)) {
167         return UNKNOWN_ERROR;
168     }
169     return OK;
170 }
171 
172 struct FetchFunction {
173     RuntimeInfo::FetchFlags flags;
174     std::function<status_t(RuntimeInfoFetcher*, RuntimeInfo::FetchFlags)> fetch;
175     std::string description;
176 };
177 
fetchAllInformation(RuntimeInfo::FetchFlags flags)178 status_t RuntimeInfoFetcher::fetchAllInformation(RuntimeInfo::FetchFlags flags) {
179     using F = RuntimeInfo::FetchFlag;
180     using RF = RuntimeInfoFetcher;
181     // clang-format off
182     const static std::vector<FetchFunction> gFetchFunctions({
183         {F::CPU_VERSION | F::KERNEL_FCM, &RF::fetchVersion,            "/proc/version"},
184         {F::CONFIG_GZ,                   &RF::fetchKernelConfigs,      "/proc/config.gz"},
185         {F::CPU_INFO,                    &RF::fetchCpuInfo,            "/proc/cpuinfo"},
186         {F::POLICYVERS,                  &RF::fetchKernelSepolicyVers, "kernel sepolicy version"},
187         {F::AVB,                         &RF::fetchAvb,                "avb version"},
188     });
189     // clang-format on
190 
191     status_t err;
192     for (const auto& fetchFunction : gFetchFunctions)
193         if ((flags & fetchFunction.flags) && ((err = fetchFunction.fetch(this, flags)) != OK))
194             LOG(WARNING) << "Cannot fetch or parse " << fetchFunction.description << ": "
195                          << strerror(-err);
196 
197     return OK;
198 }
199 
fetchAllInformation(RuntimeInfo::FetchFlags flags)200 status_t RuntimeInfo::fetchAllInformation(RuntimeInfo::FetchFlags flags) {
201     return RuntimeInfoFetcher(this).fetchAllInformation(flags);
202 }
203 
204 } // namespace vintf
205 } // namespace android
206