2 * cn_proc.c - process events connector
4 * Copyright (C) Matt Helsley, IBM Corp. 2005
5 * Based on cn_fork.c by Guillaume Thouvenin <guillaume.thouvenin@bull.net>
6 * Original copyright notice follows:
7 * Copyright (C) 2005 BULL SA.
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/init.h>
28 #include <asm/atomic.h>
30 #include <linux/cn_proc.h>
32 #define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event))
34 static atomic_t proc_event_num_listeners
= ATOMIC_INIT(0);
35 static struct cb_id cn_proc_event_id
= { CN_IDX_PROC
, CN_VAL_PROC
};
37 /* proc_counts is used as the sequence number of the netlink message */
38 static DEFINE_PER_CPU(__u32
, proc_event_counts
) = { 0 };
40 static inline void get_seq(__u32
*ts
, int *cpu
)
42 *ts
= get_cpu_var(proc_event_counts
)++;
43 *cpu
= smp_processor_id();
44 put_cpu_var(proc_counts
);
47 void proc_fork_connector(struct task_struct
*task
)
50 struct proc_event
*ev
;
51 __u8 buffer
[CN_PROC_MSG_SIZE
];
53 if (atomic_read(&proc_event_num_listeners
) < 1)
56 msg
= (struct cn_msg
*)buffer
;
57 ev
= (struct proc_event
*)msg
->data
;
58 get_seq(&msg
->seq
, &ev
->cpu
);
59 ev
->what
= PROC_EVENT_FORK
;
60 ev
->event_data
.fork
.parent_pid
= task
->real_parent
->pid
;
61 ev
->event_data
.fork
.parent_tgid
= task
->real_parent
->tgid
;
62 ev
->event_data
.fork
.child_pid
= task
->pid
;
63 ev
->event_data
.fork
.child_tgid
= task
->tgid
;
65 memcpy(&msg
->id
, &cn_proc_event_id
, sizeof(msg
->id
));
66 msg
->ack
= 0; /* not used */
67 msg
->len
= sizeof(*ev
);
68 /* If cn_netlink_send() failed, the data is not sent */
69 cn_netlink_send(msg
, CN_IDX_PROC
, GFP_KERNEL
);
72 void proc_exec_connector(struct task_struct
*task
)
75 struct proc_event
*ev
;
76 __u8 buffer
[CN_PROC_MSG_SIZE
];
78 if (atomic_read(&proc_event_num_listeners
) < 1)
81 msg
= (struct cn_msg
*)buffer
;
82 ev
= (struct proc_event
*)msg
->data
;
83 get_seq(&msg
->seq
, &ev
->cpu
);
84 ev
->what
= PROC_EVENT_EXEC
;
85 ev
->event_data
.exec
.process_pid
= task
->pid
;
86 ev
->event_data
.exec
.process_tgid
= task
->tgid
;
88 memcpy(&msg
->id
, &cn_proc_event_id
, sizeof(msg
->id
));
89 msg
->ack
= 0; /* not used */
90 msg
->len
= sizeof(*ev
);
91 cn_netlink_send(msg
, CN_IDX_PROC
, GFP_KERNEL
);
94 void proc_id_connector(struct task_struct
*task
, int which_id
)
97 struct proc_event
*ev
;
98 __u8 buffer
[CN_PROC_MSG_SIZE
];
100 if (atomic_read(&proc_event_num_listeners
) < 1)
103 msg
= (struct cn_msg
*)buffer
;
104 ev
= (struct proc_event
*)msg
->data
;
106 ev
->event_data
.id
.process_pid
= task
->pid
;
107 ev
->event_data
.id
.process_tgid
= task
->tgid
;
108 if (which_id
== PROC_EVENT_UID
) {
109 ev
->event_data
.id
.r
.ruid
= task
->uid
;
110 ev
->event_data
.id
.e
.euid
= task
->euid
;
111 } else if (which_id
== PROC_EVENT_GID
) {
112 ev
->event_data
.id
.r
.rgid
= task
->gid
;
113 ev
->event_data
.id
.e
.egid
= task
->egid
;
116 get_seq(&msg
->seq
, &ev
->cpu
);
118 memcpy(&msg
->id
, &cn_proc_event_id
, sizeof(msg
->id
));
119 msg
->ack
= 0; /* not used */
120 msg
->len
= sizeof(*ev
);
121 cn_netlink_send(msg
, CN_IDX_PROC
, GFP_KERNEL
);
124 void proc_exit_connector(struct task_struct
*task
)
127 struct proc_event
*ev
;
128 __u8 buffer
[CN_PROC_MSG_SIZE
];
130 if (atomic_read(&proc_event_num_listeners
) < 1)
133 msg
= (struct cn_msg
*)buffer
;
134 ev
= (struct proc_event
*)msg
->data
;
135 get_seq(&msg
->seq
, &ev
->cpu
);
136 ev
->what
= PROC_EVENT_EXIT
;
137 ev
->event_data
.exit
.process_pid
= task
->pid
;
138 ev
->event_data
.exit
.process_tgid
= task
->tgid
;
139 ev
->event_data
.exit
.exit_code
= task
->exit_code
;
140 ev
->event_data
.exit
.exit_signal
= task
->exit_signal
;
142 memcpy(&msg
->id
, &cn_proc_event_id
, sizeof(msg
->id
));
143 msg
->ack
= 0; /* not used */
144 msg
->len
= sizeof(*ev
);
145 cn_netlink_send(msg
, CN_IDX_PROC
, GFP_KERNEL
);
149 * Send an acknowledgement message to userspace
151 * Use 0 for success, EFOO otherwise.
152 * Note: this is the negative of conventional kernel error
153 * values because it's not being returned via syscall return
156 static void cn_proc_ack(int err
, int rcvd_seq
, int rcvd_ack
)
159 struct proc_event
*ev
;
160 __u8 buffer
[CN_PROC_MSG_SIZE
];
162 if (atomic_read(&proc_event_num_listeners
) < 1)
165 msg
= (struct cn_msg
*)buffer
;
166 ev
= (struct proc_event
*)msg
->data
;
169 ev
->what
= PROC_EVENT_NONE
;
170 ev
->event_data
.ack
.err
= err
;
171 memcpy(&msg
->id
, &cn_proc_event_id
, sizeof(msg
->id
));
172 msg
->ack
= rcvd_ack
+ 1;
173 msg
->len
= sizeof(*ev
);
174 cn_netlink_send(msg
, CN_IDX_PROC
, GFP_KERNEL
);
179 * @data: message sent from userspace via the connector
181 static void cn_proc_mcast_ctl(void *data
)
183 struct cn_msg
*msg
= data
;
184 enum proc_cn_mcast_op
*mc_op
= NULL
;
187 if (msg
->len
!= sizeof(*mc_op
))
190 mc_op
= (enum proc_cn_mcast_op
*)msg
->data
;
192 case PROC_CN_MCAST_LISTEN
:
193 atomic_inc(&proc_event_num_listeners
);
195 case PROC_CN_MCAST_IGNORE
:
196 atomic_dec(&proc_event_num_listeners
);
202 cn_proc_ack(err
, msg
->seq
, msg
->ack
);
206 * cn_proc_init - initialization entry point
208 * Adds the connector callback to the connector driver.
210 static int __init
cn_proc_init(void)
214 if ((err
= cn_add_callback(&cn_proc_event_id
, "cn_proc",
215 &cn_proc_mcast_ctl
))) {
216 printk(KERN_WARNING
"cn_proc failed to register\n");
222 module_init(cn_proc_init
);