forked from Slashed/daemon.node
-
Notifications
You must be signed in to change notification settings - Fork 2
/
daemon.cc
230 lines (198 loc) · 5.88 KB
/
daemon.cc
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
/*
* Daemon.node: A node.JS addon that allows creating Unix/Linux Daemons in pure Javascript.
*
* Copyright 2010 (c) <arthur@norgic.com>
* Modified By: Pedro Teixeira 2010
* Modified By: James Haliday 2010
* Modified By: Charlie Robbins 2010
* Modified By: Zak Taylor 2010
* Modified By: Daniel Bartlett 2011
* Modified By: Charlie Robbins 2011
*
* Under MIT License. See LICENSE file.
*
*/
#include <v8.h>
#include <node.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <pwd.h>
#include <string.h>
#define PID_MAXLEN 10
using namespace v8;
using namespace node;
//
// Go through special routines to become a daemon.
// if successful, returns daemon pid
//
static Handle<Value> Start(const Arguments& args) {
HandleScope scope;
pid_t sid, pid = fork();
int i, new_fd;
if (pid < 0) exit(1);
else if (pid > 0) exit(0);
if (pid == 0) {
// Child process: We need to tell libev that we are forking because
// kqueue can't deal with this gracefully.
//
// See: http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_fork_code_the_audacity_to_re
ev_default_fork();
sid = setsid();
if(sid < 0) exit(1);
// Close stdin
freopen("/dev/null", "r", stdin);
if (args.Length() > 0 && args[0]->IsInt32()) {
new_fd = args[0]->Int32Value();
dup2(new_fd, STDOUT_FILENO);
dup2(new_fd, STDERR_FILENO);
}
else {
freopen("/dev/null", "w", stderr);
freopen("/dev/null", "w", stdout);
}
}
return scope.Close(Number::New(getpid()));
}
//
// Close stdin by redirecting it to /dev/null
//
Handle<Value> CloseStdin(const Arguments& args) {
freopen("/dev/null", "r", stdin);
}
//
// Close stderr by redirecting to /dev/null
//
Handle<Value> CloseStderr(const Arguments& args) {
freopen("/dev/null", "w", stderr);
}
//
// Close stdout by redirecting to /dev/null
//
Handle<Value> CloseStdout(const Arguments& args) {
freopen("/dev/null", "w", stdout);
}
//
// Closes all stdio by redirecting to /dev/null
//
Handle<Value> CloseStdio(const Arguments& args) {
freopen("/dev/null", "r", stdin);
freopen("/dev/null", "w", stderr);
freopen("/dev/null", "w", stdout);
}
//
// File-lock to make sure that only one instance of daemon is running, also for storing pid
// lock (filename)
// @filename: a path to a lock-file.
//
// Note: if filename doesn't exist, it will be created when function is called.
//
Handle<Value> LockD(const Arguments& args) {
if (!args[0]->IsString())
return Boolean::New(false);
String::Utf8Value data(args[0]->ToString());
char pid_str[PID_MAXLEN+1];
int lfp = open(*data, O_RDWR | O_CREAT | O_TRUNC, 0640);
if(lfp < 0) exit(1);
if(lockf(lfp, F_TLOCK, 0) < 0) return Boolean::New(false);
int len = snprintf(pid_str, PID_MAXLEN, "%d", getpid());
write(lfp, pid_str, len);
fsync(lfp);
return Boolean::New(true);
}
Handle<Value> SetSid(const Arguments& args) {
pid_t sid;
sid = setsid();
return Integer::New(sid);
}
const char* ToCString(const v8::String::Utf8Value& value) {
return *value ? *value : "<string conversion failed>";
}
//
// Set the chroot of this process. You probably want to be sure stuff is in here.
// chroot (folder)
// @folder {string}: The new root
//
Handle<Value> Chroot(const Arguments& args) {
if (args.Length() < 1) {
return ThrowException(Exception::TypeError(
String::New("Must have one argument; a string of the folder to chroot to.")
));
}
uid_t uid;
int rv;
String::Utf8Value folderUtf8(args[0]->ToString());
const char *folder = ToCString(folderUtf8);
rv = chroot(folder);
if (rv != 0) {
return ThrowException(ErrnoException(errno, "chroot"));
}
chdir("/");
return Boolean::New(true);
}
//
// Allow changing the real and effective user ID of this process
// so a root process can become unprivileged
//
Handle<Value> SetReuid(const Arguments& args) {
if (args.Length() == 0 || (!args[0]->IsString() && !args[0]->IsInt32()))
return ThrowException(Exception::Error(
String::New("Must give a uid or username to become")
));
if (args[0]->IsString()) {
String::AsciiValue username(args[0]);
struct passwd* pwd_entry = getpwnam(*username);
if (pwd_entry) {
setreuid(pwd_entry->pw_uid, pwd_entry->pw_uid);
return Boolean::New(true);
}
else {
return ThrowException(Exception::Error(
String::New("User not found")
));
}
}
else if (args[0]->IsInt32()) {
uid_t uid;
uid = args[0]->Int32Value();
setreuid(uid, uid);
return Boolean::New(true);
}
}
Handle<Value> ExecVP(const Arguments& args) {
if (args.Length() < 2 || !args[0]->IsString() || !args[1]->IsArray()) {
return ThrowException(Exception::Error(String::New("Bad argument.")));
}
String::Utf8Value fileutf8(args[0]->ToString());
char *file = strdup(*fileutf8);
Local<Array> argv_handle = Local<Array>::Cast(args[1]);
int i;
int argc = argv_handle->Length();
int argv_length = argc + 1 + 1;
char **argv = new char*[argv_length]; // heap allocated to detect errors
argv[0] = strdup(*fileutf8); // + 1 for file
argv[argv_length-1] = NULL; // + 1 for NULL;
for (i = 0; i < argc; i++) {
String::Utf8Value arg(argv_handle->Get(Integer::New(i))->ToString());
argv[i+1] = strdup(*arg);
}
execvp(file, argv);
}
//
// Initialize this add-on
//
extern "C" void init(Handle<Object> target) {
HandleScope scope;
NODE_SET_METHOD(target, "start", Start);
NODE_SET_METHOD(target, "lock", LockD);
NODE_SET_METHOD(target, "setsid", SetSid);
NODE_SET_METHOD(target, "chroot", Chroot);
NODE_SET_METHOD(target, "setreuid", SetReuid);
NODE_SET_METHOD(target, "execvp", ExecVP);
NODE_SET_METHOD(target, "closeStderr", CloseStderr);
NODE_SET_METHOD(target, "closeStdout", CloseStdout);
NODE_SET_METHOD(target, "closeStdin", CloseStdin);
NODE_SET_METHOD(target, "closeStdio", CloseStdio);
}