1 /*
2  * Copyright (C) 2015 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 #define TRACE_TAG ADB
18 
19 #include "adb_utils.h"
20 #include "adb_unique_fd.h"
21 
22 #include <stdlib.h>
23 #include <sys/stat.h>
24 #include <sys/types.h>
25 #include <unistd.h>
26 
27 #include <algorithm>
28 #include <vector>
29 
30 #include <android-base/file.h>
31 #include <android-base/logging.h>
32 #include <android-base/parseint.h>
33 #include <android-base/stringprintf.h>
34 #include <android-base/strings.h>
35 
36 #include "adb.h"
37 #include "adb_trace.h"
38 #include "sysdeps.h"
39 
40 #ifdef _WIN32
41 #  ifndef WIN32_LEAN_AND_MEAN
42 #    define WIN32_LEAN_AND_MEAN
43 #  endif
44 #  include "windows.h"
45 #  include "shlobj.h"
46 #else
47 #include <pwd.h>
48 #endif
49 
50 
51 #if defined(_WIN32)
52 constexpr char kNullFileName[] = "NUL";
53 #else
54 constexpr char kNullFileName[] = "/dev/null";
55 #endif
56 
close_stdin()57 void close_stdin() {
58     int fd = unix_open(kNullFileName, O_RDONLY);
59     if (fd == -1) {
60         fatal_errno("failed to open %s", kNullFileName);
61     }
62 
63     if (TEMP_FAILURE_RETRY(dup2(fd, STDIN_FILENO)) == -1) {
64         fatal_errno("failed to redirect stdin to %s", kNullFileName);
65     }
66     unix_close(fd);
67 }
68 
getcwd(std::string * s)69 bool getcwd(std::string* s) {
70   char* cwd = getcwd(nullptr, 0);
71   if (cwd != nullptr) *s = cwd;
72   free(cwd);
73   return (cwd != nullptr);
74 }
75 
directory_exists(const std::string & path)76 bool directory_exists(const std::string& path) {
77   struct stat sb;
78   return stat(path.c_str(), &sb) != -1 && S_ISDIR(sb.st_mode);
79 }
80 
escape_arg(const std::string & s)81 std::string escape_arg(const std::string& s) {
82   std::string result = s;
83 
84   // Escape any ' in the string (before we single-quote the whole thing).
85   // The correct way to do this for the shell is to replace ' with '\'' --- that is,
86   // close the existing single-quoted string, escape a single single-quote, and start
87   // a new single-quoted string. Like the C preprocessor, the shell will concatenate
88   // these pieces into one string.
89   for (size_t i = 0; i < s.size(); ++i) {
90     if (s[i] == '\'') {
91       result.insert(i, "'\\'");
92       i += 2;
93     }
94   }
95 
96   // Prefix and suffix the whole string with '.
97   result.insert(result.begin(), '\'');
98   result.push_back('\'');
99   return result;
100 }
101 
102 // Given a relative or absolute filepath, create the directory hierarchy
103 // as needed. Returns true if the hierarchy is/was setup.
mkdirs(const std::string & path)104 bool mkdirs(const std::string& path) {
105   // TODO: all the callers do unlink && mkdirs && adb_creat ---
106   // that's probably the operation we should expose.
107 
108   // Implementation Notes:
109   //
110   // Pros:
111   // - Uses dirname, so does not need to deal with OS_PATH_SEPARATOR.
112   // - On Windows, uses mingw dirname which accepts '/' and '\\', drive letters
113   //   (C:\foo), UNC paths (\\server\share\dir\dir\file), and Unicode (when
114   //   combined with our adb_mkdir() which takes UTF-8).
115   // - Is optimistic wrt thinking that a deep directory hierarchy will exist.
116   //   So it does as few stat()s as possible before doing mkdir()s.
117   // Cons:
118   // - Recursive, so it uses stack space relative to number of directory
119   //   components.
120 
121   // If path points to a symlink to a directory, that's fine.
122   struct stat sb;
123   if (stat(path.c_str(), &sb) != -1 && S_ISDIR(sb.st_mode)) {
124     return true;
125   }
126 
127   const std::string parent(android::base::Dirname(path));
128 
129   // If dirname returned the same path as what we passed in, don't go recursive.
130   // This can happen on Windows when walking up the directory hierarchy and not
131   // finding anything that already exists (unlike POSIX that will eventually
132   // find . or /).
133   if (parent == path) {
134     errno = ENOENT;
135     return false;
136   }
137 
138   // Recursively make parent directories of 'path'.
139   if (!mkdirs(parent)) {
140     return false;
141   }
142 
143   // Now that the parent directory hierarchy of 'path' has been ensured,
144   // create path itself.
145   if (adb_mkdir(path, 0775) == -1) {
146     const int saved_errno = errno;
147     // If someone else created the directory, that is ok.
148     if (directory_exists(path)) {
149       return true;
150     }
151     // There might be a pre-existing file at 'path', or there might have been some other error.
152     errno = saved_errno;
153     return false;
154   }
155 
156   return true;
157 }
158 
dump_hex(const void * data,size_t byte_count)159 std::string dump_hex(const void* data, size_t byte_count) {
160     byte_count = std::min(byte_count, size_t(16));
161 
162     const uint8_t* p = reinterpret_cast<const uint8_t*>(data);
163 
164     std::string line;
165     for (size_t i = 0; i < byte_count; ++i) {
166         android::base::StringAppendF(&line, "%02x", p[i]);
167     }
168     line.push_back(' ');
169 
170     for (size_t i = 0; i < byte_count; ++i) {
171         int ch = p[i];
172         line.push_back(isprint(ch) ? ch : '.');
173     }
174 
175     return line;
176 }
177 
perror_str(const char * msg)178 std::string perror_str(const char* msg) {
179     return android::base::StringPrintf("%s: %s", msg, strerror(errno));
180 }
181 
182 #if !defined(_WIN32)
183 // Windows version provided in sysdeps_win32.cpp
set_file_block_mode(int fd,bool block)184 bool set_file_block_mode(int fd, bool block) {
185     int flags = fcntl(fd, F_GETFL, 0);
186     if (flags == -1) {
187         PLOG(ERROR) << "failed to fcntl(F_GETFL) for fd " << fd;
188         return false;
189     }
190     flags = block ? (flags & ~O_NONBLOCK) : (flags | O_NONBLOCK);
191     if (fcntl(fd, F_SETFL, flags) != 0) {
192         PLOG(ERROR) << "failed to fcntl(F_SETFL) for fd " << fd << ", flags " << flags;
193         return false;
194     }
195     return true;
196 }
197 #endif
198 
forward_targets_are_valid(const std::string & source,const std::string & dest,std::string * error)199 bool forward_targets_are_valid(const std::string& source, const std::string& dest,
200                                std::string* error) {
201     if (android::base::StartsWith(source, "tcp:")) {
202         // The source port may be 0 to allow the system to select an open port.
203         int port;
204         if (!android::base::ParseInt(&source[4], &port) || port < 0) {
205             *error = android::base::StringPrintf("Invalid source port: '%s'", &source[4]);
206             return false;
207         }
208     }
209 
210     if (android::base::StartsWith(dest, "tcp:")) {
211         // The destination port must be > 0.
212         int port;
213         if (!android::base::ParseInt(&dest[4], &port) || port <= 0) {
214             *error = android::base::StringPrintf("Invalid destination port: '%s'", &dest[4]);
215             return false;
216         }
217     }
218 
219     return true;
220 }
221 
adb_get_homedir_path()222 std::string adb_get_homedir_path() {
223 #ifdef _WIN32
224     WCHAR path[MAX_PATH];
225     const HRESULT hr = SHGetFolderPathW(NULL, CSIDL_PROFILE, NULL, 0, path);
226     if (FAILED(hr)) {
227         D("SHGetFolderPathW failed: %s", android::base::SystemErrorCodeToString(hr).c_str());
228         return {};
229     }
230     std::string home_str;
231     if (!android::base::WideToUTF8(path, &home_str)) {
232         return {};
233     }
234     return home_str;
235 #else
236     if (const char* const home = getenv("HOME")) {
237         return home;
238     }
239 
240     struct passwd pwent;
241     struct passwd* result;
242     int pwent_max = sysconf(_SC_GETPW_R_SIZE_MAX);
243     std::vector<char> buf(pwent_max);
244     int rc = getpwuid_r(getuid(), &pwent, buf.data(), buf.size(), &result);
245     if (rc == 0 && result) {
246         return result->pw_dir;
247     }
248 
249     LOG(FATAL) << "failed to get user home directory";
250     return {};
251 #endif
252 }
253 
adb_get_android_dir_path()254 std::string adb_get_android_dir_path() {
255     std::string user_dir = adb_get_homedir_path();
256     std::string android_dir = user_dir + OS_PATH_SEPARATOR + ".android";
257     struct stat buf;
258     if (stat(android_dir.c_str(), &buf) == -1) {
259         if (adb_mkdir(android_dir.c_str(), 0750) == -1) {
260             PLOG(FATAL) << "Cannot mkdir '" << android_dir << "'";
261         }
262     }
263     return android_dir;
264 }
265 
Close(int fd)266 void AdbCloser::Close(int fd) {
267     adb_close(fd);
268 }
269 
usage(const char * fmt,...)270 int usage(const char* fmt, ...) {
271     fprintf(stderr, "adb: ");
272 
273     va_list ap;
274     va_start(ap, fmt);
275     vfprintf(stderr, fmt, ap);
276     va_end(ap);
277 
278     fprintf(stderr, "\n");
279     return 1;
280 }
281