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
|
#ifdef __linux__ /* only build on linux */
#include <ruby.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/socket.h>
#include <linux/netlink.h>
#include <linux/connector.h>
#define _LINUX_TIME_H
#include <linux/cn_proc.h>
#include <errno.h>
static VALUE mGod;
static VALUE cNetlinkHandler;
static VALUE cEventHandler;
static ID proc_exit;
static ID proc_fork;
static ID m_call;
static ID m_watching_pid;
static int nl_sock; /* socket for netlink connection */
VALUE
nlh_handle_events()
{
char buff[CONNECTOR_MAX_MSG_SIZE];
struct nlmsghdr *hdr;
struct proc_event *event;
VALUE extra_data;
fd_set fds;
FD_ZERO(&fds);
FD_SET(nl_sock, &fds);
if (0 > rb_thread_select(nl_sock + 1, &fds, NULL, NULL, NULL)) {
rb_raise(rb_eStandardError, "%s", strerror(errno));
}
/* If there were no events detected, return */
if (! FD_ISSET(nl_sock, &fds)) {
return INT2FIX(0);
}
/* if there are events, make calls */
if (-1 == recv(nl_sock, buff, sizeof(buff), 0)) {
rb_raise(rb_eStandardError, "%s", strerror(errno));
}
hdr = (struct nlmsghdr *)buff;
if (NLMSG_ERROR == hdr->nlmsg_type) {
rb_raise(rb_eStandardError, "%s", strerror(errno));
} else if (NLMSG_DONE == hdr->nlmsg_type) {
event = (struct proc_event *)((struct cn_msg *)NLMSG_DATA(hdr))->data;
switch(event->what) {
case PROC_EVENT_EXIT:
if (Qnil == rb_funcall(cEventHandler, m_watching_pid, 1, INT2FIX(event->event_data.exit.process_pid))) {
return INT2FIX(0);
}
extra_data = rb_hash_new();
rb_hash_aset(extra_data, ID2SYM(rb_intern("pid")), INT2FIX(event->event_data.exit.process_pid));
rb_hash_aset(extra_data, ID2SYM(rb_intern("exit_code")), INT2FIX(event->event_data.exit.exit_code));
rb_hash_aset(extra_data, ID2SYM(rb_intern("exit_signal")), INT2FIX(event->event_data.exit.exit_signal));
rb_hash_aset(extra_data, ID2SYM(rb_intern("thread_group_id")), INT2FIX(event->event_data.exit.process_tgid));
rb_funcall(cEventHandler, m_call, 3, INT2FIX(event->event_data.exit.process_pid), ID2SYM(proc_exit), extra_data);
return INT2FIX(1);
case PROC_EVENT_FORK:
if (Qnil == rb_funcall(cEventHandler, m_watching_pid, 1, INT2FIX(event->event_data.fork.parent_pid))) {
return INT2FIX(0);
}
extra_data = rb_hash_new();
rb_hash_aset(extra_data, ID2SYM(rb_intern("parent_pid")), INT2FIX(event->event_data.fork.parent_pid));
rb_hash_aset(extra_data, ID2SYM(rb_intern("parent_thread_group_id")), INT2FIX(event->event_data.fork.parent_tgid));
rb_hash_aset(extra_data, ID2SYM(rb_intern("child_pid")), INT2FIX(event->event_data.fork.child_pid));
rb_hash_aset(extra_data, ID2SYM(rb_intern("child_thread_group_id")), INT2FIX(event->event_data.fork.child_tgid));
rb_funcall(cEventHandler, m_call, 3, INT2FIX(event->event_data.fork.parent_pid), ID2SYM(proc_fork), extra_data);
return INT2FIX(1);
default:
break;
}
}
return Qnil;
}
#define NL_MESSAGE_SIZE (sizeof(struct nlmsghdr) + sizeof(struct cn_msg) + \
sizeof(int))
void
connect_to_netlink()
{
struct sockaddr_nl sa_nl; /* netlink interface info */
char buff[NL_MESSAGE_SIZE];
struct nlmsghdr *hdr; /* for telling netlink what we want */
struct cn_msg *msg; /* the actual connector message */
/* connect to netlink socket */
nl_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
if (-1 == nl_sock) {
rb_raise(rb_eStandardError, "%s", strerror(errno));
}
bzero(&sa_nl, sizeof(sa_nl));
sa_nl.nl_family = AF_NETLINK;
sa_nl.nl_groups = CN_IDX_PROC;
sa_nl.nl_pid = getpid();
if (-1 == bind(nl_sock, (struct sockaddr *)&sa_nl, sizeof(sa_nl))) {
rb_raise(rb_eStandardError, "%s", strerror(errno));
}
/* Fill header */
hdr = (struct nlmsghdr *)buff;
hdr->nlmsg_len = NL_MESSAGE_SIZE;
hdr->nlmsg_type = NLMSG_DONE;
hdr->nlmsg_flags = 0;
hdr->nlmsg_seq = 0;
hdr->nlmsg_pid = getpid();
/* Fill message */
msg = (struct cn_msg *)NLMSG_DATA(hdr);
msg->id.idx = CN_IDX_PROC; /* Connecting to process information */
msg->id.val = CN_VAL_PROC;
msg->seq = 0;
msg->ack = 0;
msg->flags = 0;
msg->len = sizeof(int);
*(int*)msg->data = PROC_CN_MCAST_LISTEN;
if (-1 == send(nl_sock, hdr, hdr->nlmsg_len, 0)) {
rb_raise(rb_eStandardError, "%s", strerror(errno));
}
}
void
Init_netlink_handler_ext()
{
proc_exit = rb_intern("proc_exit");
proc_fork = rb_intern("proc_fork");
m_call = rb_intern("call");
m_watching_pid = rb_intern("watching_pid?");
mGod = rb_const_get(rb_cObject, rb_intern("God"));
cEventHandler = rb_const_get(mGod, rb_intern("EventHandler"));
cNetlinkHandler = rb_define_class_under(mGod, "NetlinkHandler", rb_cObject);
rb_define_singleton_method(cNetlinkHandler, "handle_events", nlh_handle_events, 0);
connect_to_netlink();
}
#endif
|
