1 /*
2  * Copyright (C) 2008 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 <stdio.h>
18 #include <stdlib.h>
19 #include <unistd.h>
20 #include <string.h>
21 #include <signal.h>
22 #include <errno.h>
23 #include <fcntl.h>
24 #include <stdlib.h>
25 #include <poll.h>
26 
27 #include <sys/socket.h>
28 #include <sys/select.h>
29 #include <sys/time.h>
30 #include <sys/types.h>
31 #include <sys/un.h>
32 
33 #include <android-base/stringprintf.h>
34 
35 #include <cutils/sockets.h>
36 #include <private/android_filesystem_config.h>
37 
38 static void usage(char *progname);
39 static int do_monitor(int sock, int stop_after_cmd);
40 static int do_cmd(int sock, int argc, char **argv);
41 
42 static constexpr int kCommandTimeoutMs = 20 * 1000;
43 
main(int argc,char ** argv)44 int main(int argc, char **argv) {
45     int sock;
46     int wait_for_socket;
47     char *progname;
48 
49     progname = argv[0];
50 
51     wait_for_socket = argc > 1 && strcmp(argv[1], "--wait") == 0;
52     if (wait_for_socket) {
53         argv++;
54         argc--;
55     }
56 
57     if (argc < 2) {
58         usage(progname);
59         exit(5);
60     }
61 
62     const char* sockname = "vold";
63     if (!strcmp(argv[1], "cryptfs")) {
64         sockname = "cryptd";
65     }
66 
67     while ((sock = socket_local_client(sockname,
68                                  ANDROID_SOCKET_NAMESPACE_RESERVED,
69                                  SOCK_STREAM)) < 0) {
70         if (!wait_for_socket) {
71             fprintf(stdout, "Error connecting to %s: %s\n", sockname, strerror(errno));
72             exit(4);
73         } else {
74             usleep(10000);
75         }
76     }
77 
78     if (!strcmp(argv[1], "monitor")) {
79         exit(do_monitor(sock, 0));
80     } else {
81         exit(do_cmd(sock, argc, argv));
82     }
83 }
84 
do_cmd(int sock,int argc,char ** argv)85 static int do_cmd(int sock, int argc, char **argv) {
86     int seq = getpid();
87 
88     std::string cmd(android::base::StringPrintf("%d ", seq));
89     for (int i = 1; i < argc; i++) {
90         if (!strchr(argv[i], ' ')) {
91             cmd.append(argv[i]);
92         } else {
93             cmd.push_back('\"');
94             cmd.append(argv[i]);
95             cmd.push_back('\"');
96         }
97 
98         if (i < argc - 1) {
99             cmd.push_back(' ');
100         }
101     }
102 
103     if (TEMP_FAILURE_RETRY(write(sock, cmd.c_str(), cmd.length() + 1)) < 0) {
104         fprintf(stderr, "Failed to write command: %s\n", strerror(errno));
105         return errno;
106     }
107 
108     return do_monitor(sock, seq);
109 }
110 
do_monitor(int sock,int stop_after_seq)111 static int do_monitor(int sock, int stop_after_seq) {
112     char buffer[4096];
113     int timeout = kCommandTimeoutMs;
114 
115     if (stop_after_seq == 0) {
116         fprintf(stderr, "Connected to vold\n");
117         timeout = -1;
118     }
119 
120     while (1) {
121         struct pollfd poll_sock = { sock, POLLIN, 0 };
122         int rc = TEMP_FAILURE_RETRY(poll(&poll_sock, 1, timeout));
123         if (rc == 0) {
124             fprintf(stderr, "Timeout waiting for %d\n", stop_after_seq);
125             return ETIMEDOUT;
126         } else if (rc < 0) {
127             fprintf(stderr, "Failed during poll: %s\n", strerror(errno));
128             return errno;
129         }
130 
131         if (!(poll_sock.revents & POLLIN)) {
132             fprintf(stderr, "No data; trying again\n");
133             continue;
134         }
135 
136         memset(buffer, 0, sizeof(buffer));
137         rc = TEMP_FAILURE_RETRY(read(sock, buffer, sizeof(buffer)));
138         if (rc == 0) {
139             fprintf(stderr, "Lost connection, did vold crash?\n");
140             return ECONNRESET;
141         } else if (rc < 0) {
142             fprintf(stderr, "Error reading data: %s\n", strerror(errno));
143             return errno;
144         }
145 
146         int offset = 0;
147         for (int i = 0; i < rc; i++) {
148             if (buffer[i] == '\0') {
149                 char* res = buffer + offset;
150                 fprintf(stdout, "%s\n", res);
151 
152                 int code = atoi(strtok(res, " "));
153                 if (code >= 200 && code < 600) {
154                     int seq = atoi(strtok(nullptr, " "));
155                     if (seq == stop_after_seq) {
156                         if (code == 200) {
157                             return 0;
158                         } else {
159                             return code;
160                         }
161                     }
162                 }
163 
164                 offset = i + 1;
165             }
166         }
167     }
168     return EIO;
169 }
170 
usage(char * progname)171 static void usage(char *progname) {
172     fprintf(stderr,
173             "Usage: %s [--wait] <monitor>|<cmd> [arg1] [arg2...]\n", progname);
174 }
175