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/ktime.h>
28 #include <linux/init.h>
29 #include <linux/connector.h>
30 #include <linux/gfp.h>
31 #include <linux/ptrace.h>
32 #include <linux/atomic.h>
34 #include <linux/cn_proc.h>
37 * Size of a cn_msg followed by a proc_event structure. Since the
38 * sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we
39 * add one 4-byte word to the size here, and then start the actual
40 * cn_msg structure 4 bytes into the stack buffer. The result is that
41 * the immediately following proc_event structure is aligned to 8 bytes.
43 #define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4)
45 /* See comment above; we test our assumption about sizeof struct cn_msg here. */
46 static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer)
48 BUILD_BUG_ON(sizeof(struct cn_msg) != 20);
49 return (struct cn_msg *)(buffer + 4);
52 static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
53 static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
55 /* proc_event_counts is used as the sequence number of the netlink message */
56 static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
58 static inline void get_seq(__u32 *ts, int *cpu)
61 *ts = __this_cpu_inc_return(proc_event_counts) -1;
62 *cpu = smp_processor_id();
66 void proc_fork_connector(struct task_struct *task)
69 struct proc_event *ev;
70 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
72 struct task_struct *parent;
74 if (atomic_read(&proc_event_num_listeners) < 1)
77 msg = buffer_to_cn_msg(buffer);
78 ev = (struct proc_event*)msg->data;
79 memset(&ev->event_data, 0, sizeof(ev->event_data));
80 get_seq(&msg->seq, &ev->cpu);
81 ktime_get_ts(&ts); /* get high res monotonic timestamp */
82 ev->timestamp_ns = timespec_to_ns(&ts);
83 ev->what = PROC_EVENT_FORK;
85 parent = rcu_dereference(task->real_parent);
86 ev->event_data.fork.parent_pid = parent->pid;
87 ev->event_data.fork.parent_tgid = parent->tgid;
89 ev->event_data.fork.child_pid = task->pid;
90 ev->event_data.fork.child_tgid = task->tgid;
92 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
93 msg->ack = 0; /* not used */
94 msg->len = sizeof(*ev);
95 msg->flags = 0; /* not used */
96 /* If cn_netlink_send() failed, the data is not sent */
97 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
100 void proc_exec_connector(struct task_struct *task)
103 struct proc_event *ev;
105 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
107 if (atomic_read(&proc_event_num_listeners) < 1)
110 msg = buffer_to_cn_msg(buffer);
111 ev = (struct proc_event*)msg->data;
112 memset(&ev->event_data, 0, sizeof(ev->event_data));
113 get_seq(&msg->seq, &ev->cpu);
114 ktime_get_ts(&ts); /* get high res monotonic timestamp */
115 ev->timestamp_ns = timespec_to_ns(&ts);
116 ev->what = PROC_EVENT_EXEC;
117 ev->event_data.exec.process_pid = task->pid;
118 ev->event_data.exec.process_tgid = task->tgid;
120 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
121 msg->ack = 0; /* not used */
122 msg->len = sizeof(*ev);
123 msg->flags = 0; /* not used */
124 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
127 void proc_id_connector(struct task_struct *task, int which_id)
130 struct proc_event *ev;
131 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
133 const struct cred *cred;
135 if (atomic_read(&proc_event_num_listeners) < 1)
138 msg = buffer_to_cn_msg(buffer);
139 ev = (struct proc_event*)msg->data;
140 memset(&ev->event_data, 0, sizeof(ev->event_data));
142 ev->event_data.id.process_pid = task->pid;
143 ev->event_data.id.process_tgid = task->tgid;
145 cred = __task_cred(task);
146 if (which_id == PROC_EVENT_UID) {
147 ev->event_data.id.r.ruid = cred->uid;
148 ev->event_data.id.e.euid = cred->euid;
149 } else if (which_id == PROC_EVENT_GID) {
150 ev->event_data.id.r.rgid = cred->gid;
151 ev->event_data.id.e.egid = cred->egid;
157 get_seq(&msg->seq, &ev->cpu);
158 ktime_get_ts(&ts); /* get high res monotonic timestamp */
159 ev->timestamp_ns = timespec_to_ns(&ts);
161 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
162 msg->ack = 0; /* not used */
163 msg->len = sizeof(*ev);
164 msg->flags = 0; /* not used */
165 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
168 void proc_sid_connector(struct task_struct *task)
171 struct proc_event *ev;
173 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
175 if (atomic_read(&proc_event_num_listeners) < 1)
178 msg = buffer_to_cn_msg(buffer);
179 ev = (struct proc_event *)msg->data;
180 memset(&ev->event_data, 0, sizeof(ev->event_data));
181 get_seq(&msg->seq, &ev->cpu);
182 ktime_get_ts(&ts); /* get high res monotonic timestamp */
183 ev->timestamp_ns = timespec_to_ns(&ts);
184 ev->what = PROC_EVENT_SID;
185 ev->event_data.sid.process_pid = task->pid;
186 ev->event_data.sid.process_tgid = task->tgid;
188 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
189 msg->ack = 0; /* not used */
190 msg->len = sizeof(*ev);
191 msg->flags = 0; /* not used */
192 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
195 void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
198 struct proc_event *ev;
200 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
202 if (atomic_read(&proc_event_num_listeners) < 1)
205 msg = buffer_to_cn_msg(buffer);
206 ev = (struct proc_event *)msg->data;
207 memset(&ev->event_data, 0, sizeof(ev->event_data));
208 get_seq(&msg->seq, &ev->cpu);
209 ktime_get_ts(&ts); /* get high res monotonic timestamp */
210 ev->timestamp_ns = timespec_to_ns(&ts);
211 ev->what = PROC_EVENT_PTRACE;
212 ev->event_data.ptrace.process_pid = task->pid;
213 ev->event_data.ptrace.process_tgid = task->tgid;
214 if (ptrace_id == PTRACE_ATTACH) {
215 ev->event_data.ptrace.tracer_pid = current->pid;
216 ev->event_data.ptrace.tracer_tgid = current->tgid;
217 } else if (ptrace_id == PTRACE_DETACH) {
218 ev->event_data.ptrace.tracer_pid = 0;
219 ev->event_data.ptrace.tracer_tgid = 0;
223 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
224 msg->ack = 0; /* not used */
225 msg->len = sizeof(*ev);
226 msg->flags = 0; /* not used */
227 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
230 void proc_comm_connector(struct task_struct *task)
233 struct proc_event *ev;
235 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
237 if (atomic_read(&proc_event_num_listeners) < 1)
240 msg = buffer_to_cn_msg(buffer);
241 ev = (struct proc_event *)msg->data;
242 memset(&ev->event_data, 0, sizeof(ev->event_data));
243 get_seq(&msg->seq, &ev->cpu);
244 ktime_get_ts(&ts); /* get high res monotonic timestamp */
245 ev->timestamp_ns = timespec_to_ns(&ts);
246 ev->what = PROC_EVENT_COMM;
247 ev->event_data.comm.process_pid = task->pid;
248 ev->event_data.comm.process_tgid = task->tgid;
249 get_task_comm(ev->event_data.comm.comm, task);
251 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
252 msg->ack = 0; /* not used */
253 msg->len = sizeof(*ev);
254 msg->flags = 0; /* not used */
255 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
258 void proc_exit_connector(struct task_struct *task)
261 struct proc_event *ev;
262 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
265 if (atomic_read(&proc_event_num_listeners) < 1)
268 msg = buffer_to_cn_msg(buffer);
269 ev = (struct proc_event*)msg->data;
270 memset(&ev->event_data, 0, sizeof(ev->event_data));
271 get_seq(&msg->seq, &ev->cpu);
272 ktime_get_ts(&ts); /* get high res monotonic timestamp */
273 ev->timestamp_ns = timespec_to_ns(&ts);
274 ev->what = PROC_EVENT_EXIT;
275 ev->event_data.exit.process_pid = task->pid;
276 ev->event_data.exit.process_tgid = task->tgid;
277 ev->event_data.exit.exit_code = task->exit_code;
278 ev->event_data.exit.exit_signal = task->exit_signal;
280 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
281 msg->ack = 0; /* not used */
282 msg->len = sizeof(*ev);
283 msg->flags = 0; /* not used */
284 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
288 * Send an acknowledgement message to userspace
290 * Use 0 for success, EFOO otherwise.
291 * Note: this is the negative of conventional kernel error
292 * values because it's not being returned via syscall return
295 static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
298 struct proc_event *ev;
299 __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
302 if (atomic_read(&proc_event_num_listeners) < 1)
305 msg = buffer_to_cn_msg(buffer);
306 ev = (struct proc_event*)msg->data;
307 memset(&ev->event_data, 0, sizeof(ev->event_data));
309 ktime_get_ts(&ts); /* get high res monotonic timestamp */
310 ev->timestamp_ns = timespec_to_ns(&ts);
312 ev->what = PROC_EVENT_NONE;
313 ev->event_data.ack.err = err;
314 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
315 msg->ack = rcvd_ack + 1;
316 msg->len = sizeof(*ev);
317 msg->flags = 0; /* not used */
318 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
323 * @data: message sent from userspace via the connector
325 static void cn_proc_mcast_ctl(struct cn_msg *msg,
326 struct netlink_skb_parms *nsp)
328 enum proc_cn_mcast_op *mc_op = NULL;
331 if (msg->len != sizeof(*mc_op))
334 /* Can only change if privileged. */
335 if (!capable(CAP_NET_ADMIN)) {
340 mc_op = (enum proc_cn_mcast_op*)msg->data;
342 case PROC_CN_MCAST_LISTEN:
343 atomic_inc(&proc_event_num_listeners);
345 case PROC_CN_MCAST_IGNORE:
346 atomic_dec(&proc_event_num_listeners);
354 cn_proc_ack(err, msg->seq, msg->ack);
358 * cn_proc_init - initialization entry point
360 * Adds the connector callback to the connector driver.
362 static int __init cn_proc_init(void)
366 if ((err = cn_add_callback(&cn_proc_event_id, "cn_proc",
367 &cn_proc_mcast_ctl))) {
368 printk(KERN_WARNING "cn_proc failed to register\n");
374 module_init(cn_proc_init);