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v4.6
  1/*
  2 * cn_proc.c - process events connector
  3 *
  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.
  8 *
  9 *
 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.
 14 *
 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.
 19 *
 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
 23 */
 24
 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>
 33#include <linux/pid_namespace.h>
 34
 35#include <linux/cn_proc.h>
 36
 37/*
 38 * Size of a cn_msg followed by a proc_event structure.  Since the
 39 * sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we
 40 * add one 4-byte word to the size here, and then start the actual
 41 * cn_msg structure 4 bytes into the stack buffer.  The result is that
 42 * the immediately following proc_event structure is aligned to 8 bytes.
 43 */
 44#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4)
 45
 46/* See comment above; we test our assumption about sizeof struct cn_msg here. */
 47static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer)
 48{
 49	BUILD_BUG_ON(sizeof(struct cn_msg) != 20);
 50	return (struct cn_msg *)(buffer + 4);
 51}
 52
 53static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
 54static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
 55
 56/* proc_event_counts is used as the sequence number of the netlink message */
 57static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
 58
 59static inline void get_seq(__u32 *ts, int *cpu)
 60{
 61	preempt_disable();
 62	*ts = __this_cpu_inc_return(proc_event_counts) - 1;
 63	*cpu = smp_processor_id();
 64	preempt_enable();
 65}
 66
 67void proc_fork_connector(struct task_struct *task)
 68{
 69	struct cn_msg *msg;
 70	struct proc_event *ev;
 71	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
 
 72	struct task_struct *parent;
 73
 74	if (atomic_read(&proc_event_num_listeners) < 1)
 75		return;
 76
 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	ev->timestamp_ns = ktime_get_ns();
 
 82	ev->what = PROC_EVENT_FORK;
 83	rcu_read_lock();
 84	parent = rcu_dereference(task->real_parent);
 85	ev->event_data.fork.parent_pid = parent->pid;
 86	ev->event_data.fork.parent_tgid = parent->tgid;
 87	rcu_read_unlock();
 88	ev->event_data.fork.child_pid = task->pid;
 89	ev->event_data.fork.child_tgid = task->tgid;
 90
 91	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
 92	msg->ack = 0; /* not used */
 93	msg->len = sizeof(*ev);
 94	msg->flags = 0; /* not used */
 95	/*  If cn_netlink_send() failed, the data is not sent */
 96	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 97}
 98
 99void proc_exec_connector(struct task_struct *task)
100{
101	struct cn_msg *msg;
102	struct proc_event *ev;
 
103	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
104
105	if (atomic_read(&proc_event_num_listeners) < 1)
106		return;
107
108	msg = buffer_to_cn_msg(buffer);
109	ev = (struct proc_event *)msg->data;
110	memset(&ev->event_data, 0, sizeof(ev->event_data));
111	get_seq(&msg->seq, &ev->cpu);
112	ev->timestamp_ns = ktime_get_ns();
 
113	ev->what = PROC_EVENT_EXEC;
114	ev->event_data.exec.process_pid = task->pid;
115	ev->event_data.exec.process_tgid = task->tgid;
116
117	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
118	msg->ack = 0; /* not used */
119	msg->len = sizeof(*ev);
120	msg->flags = 0; /* not used */
121	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
122}
123
124void proc_id_connector(struct task_struct *task, int which_id)
125{
126	struct cn_msg *msg;
127	struct proc_event *ev;
128	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
 
129	const struct cred *cred;
130
131	if (atomic_read(&proc_event_num_listeners) < 1)
132		return;
133
134	msg = buffer_to_cn_msg(buffer);
135	ev = (struct proc_event *)msg->data;
136	memset(&ev->event_data, 0, sizeof(ev->event_data));
137	ev->what = which_id;
138	ev->event_data.id.process_pid = task->pid;
139	ev->event_data.id.process_tgid = task->tgid;
140	rcu_read_lock();
141	cred = __task_cred(task);
142	if (which_id == PROC_EVENT_UID) {
143		ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
144		ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
145	} else if (which_id == PROC_EVENT_GID) {
146		ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
147		ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
148	} else {
149		rcu_read_unlock();
150		return;
151	}
152	rcu_read_unlock();
153	get_seq(&msg->seq, &ev->cpu);
154	ev->timestamp_ns = ktime_get_ns();
 
155
156	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
157	msg->ack = 0; /* not used */
158	msg->len = sizeof(*ev);
159	msg->flags = 0; /* not used */
160	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
161}
162
163void proc_sid_connector(struct task_struct *task)
164{
165	struct cn_msg *msg;
166	struct proc_event *ev;
 
167	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
168
169	if (atomic_read(&proc_event_num_listeners) < 1)
170		return;
171
172	msg = buffer_to_cn_msg(buffer);
173	ev = (struct proc_event *)msg->data;
174	memset(&ev->event_data, 0, sizeof(ev->event_data));
175	get_seq(&msg->seq, &ev->cpu);
176	ev->timestamp_ns = ktime_get_ns();
 
177	ev->what = PROC_EVENT_SID;
178	ev->event_data.sid.process_pid = task->pid;
179	ev->event_data.sid.process_tgid = task->tgid;
180
181	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
182	msg->ack = 0; /* not used */
183	msg->len = sizeof(*ev);
184	msg->flags = 0; /* not used */
185	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
186}
187
188void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
189{
190	struct cn_msg *msg;
191	struct proc_event *ev;
 
192	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
193
194	if (atomic_read(&proc_event_num_listeners) < 1)
195		return;
196
197	msg = buffer_to_cn_msg(buffer);
198	ev = (struct proc_event *)msg->data;
199	memset(&ev->event_data, 0, sizeof(ev->event_data));
200	get_seq(&msg->seq, &ev->cpu);
201	ev->timestamp_ns = ktime_get_ns();
 
202	ev->what = PROC_EVENT_PTRACE;
203	ev->event_data.ptrace.process_pid  = task->pid;
204	ev->event_data.ptrace.process_tgid = task->tgid;
205	if (ptrace_id == PTRACE_ATTACH) {
206		ev->event_data.ptrace.tracer_pid  = current->pid;
207		ev->event_data.ptrace.tracer_tgid = current->tgid;
208	} else if (ptrace_id == PTRACE_DETACH) {
209		ev->event_data.ptrace.tracer_pid  = 0;
210		ev->event_data.ptrace.tracer_tgid = 0;
211	} else
212		return;
213
214	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
215	msg->ack = 0; /* not used */
216	msg->len = sizeof(*ev);
217	msg->flags = 0; /* not used */
218	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
219}
220
221void proc_comm_connector(struct task_struct *task)
222{
223	struct cn_msg *msg;
224	struct proc_event *ev;
 
225	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
226
227	if (atomic_read(&proc_event_num_listeners) < 1)
228		return;
229
230	msg = buffer_to_cn_msg(buffer);
231	ev = (struct proc_event *)msg->data;
232	memset(&ev->event_data, 0, sizeof(ev->event_data));
233	get_seq(&msg->seq, &ev->cpu);
234	ev->timestamp_ns = ktime_get_ns();
 
235	ev->what = PROC_EVENT_COMM;
236	ev->event_data.comm.process_pid  = task->pid;
237	ev->event_data.comm.process_tgid = task->tgid;
238	get_task_comm(ev->event_data.comm.comm, task);
239
240	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
241	msg->ack = 0; /* not used */
242	msg->len = sizeof(*ev);
243	msg->flags = 0; /* not used */
244	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
245}
246
247void proc_coredump_connector(struct task_struct *task)
248{
249	struct cn_msg *msg;
250	struct proc_event *ev;
251	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
 
252
253	if (atomic_read(&proc_event_num_listeners) < 1)
254		return;
255
256	msg = buffer_to_cn_msg(buffer);
257	ev = (struct proc_event *)msg->data;
258	memset(&ev->event_data, 0, sizeof(ev->event_data));
259	get_seq(&msg->seq, &ev->cpu);
260	ev->timestamp_ns = ktime_get_ns();
 
261	ev->what = PROC_EVENT_COREDUMP;
262	ev->event_data.coredump.process_pid = task->pid;
263	ev->event_data.coredump.process_tgid = task->tgid;
264
265	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
266	msg->ack = 0; /* not used */
267	msg->len = sizeof(*ev);
268	msg->flags = 0; /* not used */
269	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
270}
271
272void proc_exit_connector(struct task_struct *task)
273{
274	struct cn_msg *msg;
275	struct proc_event *ev;
276	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
 
277
278	if (atomic_read(&proc_event_num_listeners) < 1)
279		return;
280
281	msg = buffer_to_cn_msg(buffer);
282	ev = (struct proc_event *)msg->data;
283	memset(&ev->event_data, 0, sizeof(ev->event_data));
284	get_seq(&msg->seq, &ev->cpu);
285	ev->timestamp_ns = ktime_get_ns();
 
286	ev->what = PROC_EVENT_EXIT;
287	ev->event_data.exit.process_pid = task->pid;
288	ev->event_data.exit.process_tgid = task->tgid;
289	ev->event_data.exit.exit_code = task->exit_code;
290	ev->event_data.exit.exit_signal = task->exit_signal;
291
292	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
293	msg->ack = 0; /* not used */
294	msg->len = sizeof(*ev);
295	msg->flags = 0; /* not used */
296	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
297}
298
299/*
300 * Send an acknowledgement message to userspace
301 *
302 * Use 0 for success, EFOO otherwise.
303 * Note: this is the negative of conventional kernel error
304 * values because it's not being returned via syscall return
305 * mechanisms.
306 */
307static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
308{
309	struct cn_msg *msg;
310	struct proc_event *ev;
311	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
 
312
313	if (atomic_read(&proc_event_num_listeners) < 1)
314		return;
315
316	msg = buffer_to_cn_msg(buffer);
317	ev = (struct proc_event *)msg->data;
318	memset(&ev->event_data, 0, sizeof(ev->event_data));
319	msg->seq = rcvd_seq;
320	ev->timestamp_ns = ktime_get_ns();
 
321	ev->cpu = -1;
322	ev->what = PROC_EVENT_NONE;
323	ev->event_data.ack.err = err;
324	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
325	msg->ack = rcvd_ack + 1;
326	msg->len = sizeof(*ev);
327	msg->flags = 0; /* not used */
328	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
329}
330
331/**
332 * cn_proc_mcast_ctl
333 * @data: message sent from userspace via the connector
334 */
335static void cn_proc_mcast_ctl(struct cn_msg *msg,
336			      struct netlink_skb_parms *nsp)
337{
338	enum proc_cn_mcast_op *mc_op = NULL;
339	int err = 0;
340
341	if (msg->len != sizeof(*mc_op))
342		return;
343
344	/* 
345	 * Events are reported with respect to the initial pid
346	 * and user namespaces so ignore requestors from
347	 * other namespaces.
348	 */
349	if ((current_user_ns() != &init_user_ns) ||
350	    (task_active_pid_ns(current) != &init_pid_ns))
351		return;
352
353	/* Can only change if privileged. */
354	if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
355		err = EPERM;
356		goto out;
357	}
358
359	mc_op = (enum proc_cn_mcast_op *)msg->data;
360	switch (*mc_op) {
361	case PROC_CN_MCAST_LISTEN:
362		atomic_inc(&proc_event_num_listeners);
363		break;
364	case PROC_CN_MCAST_IGNORE:
365		atomic_dec(&proc_event_num_listeners);
366		break;
367	default:
368		err = EINVAL;
369		break;
370	}
371
372out:
373	cn_proc_ack(err, msg->seq, msg->ack);
374}
375
376/*
377 * cn_proc_init - initialization entry point
378 *
379 * Adds the connector callback to the connector driver.
380 */
381static int __init cn_proc_init(void)
382{
383	int err = cn_add_callback(&cn_proc_event_id,
384				  "cn_proc",
385				  &cn_proc_mcast_ctl);
386	if (err) {
387		pr_warn("cn_proc failed to register\n");
388		return err;
389	}
390	return 0;
391}
392
393module_init(cn_proc_init);
v3.15
  1/*
  2 * cn_proc.c - process events connector
  3 *
  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.
  8 *
  9 *
 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.
 14 *
 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.
 19 *
 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
 23 */
 24
 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>
 33#include <linux/pid_namespace.h>
 34
 35#include <linux/cn_proc.h>
 36
 37/*
 38 * Size of a cn_msg followed by a proc_event structure.  Since the
 39 * sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we
 40 * add one 4-byte word to the size here, and then start the actual
 41 * cn_msg structure 4 bytes into the stack buffer.  The result is that
 42 * the immediately following proc_event structure is aligned to 8 bytes.
 43 */
 44#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4)
 45
 46/* See comment above; we test our assumption about sizeof struct cn_msg here. */
 47static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer)
 48{
 49	BUILD_BUG_ON(sizeof(struct cn_msg) != 20);
 50	return (struct cn_msg *)(buffer + 4);
 51}
 52
 53static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);
 54static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC };
 55
 56/* proc_event_counts is used as the sequence number of the netlink message */
 57static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 };
 58
 59static inline void get_seq(__u32 *ts, int *cpu)
 60{
 61	preempt_disable();
 62	*ts = __this_cpu_inc_return(proc_event_counts) - 1;
 63	*cpu = smp_processor_id();
 64	preempt_enable();
 65}
 66
 67void proc_fork_connector(struct task_struct *task)
 68{
 69	struct cn_msg *msg;
 70	struct proc_event *ev;
 71	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
 72	struct timespec ts;
 73	struct task_struct *parent;
 74
 75	if (atomic_read(&proc_event_num_listeners) < 1)
 76		return;
 77
 78	msg = buffer_to_cn_msg(buffer);
 79	ev = (struct proc_event *)msg->data;
 80	memset(&ev->event_data, 0, sizeof(ev->event_data));
 81	get_seq(&msg->seq, &ev->cpu);
 82	ktime_get_ts(&ts); /* get high res monotonic timestamp */
 83	ev->timestamp_ns = timespec_to_ns(&ts);
 84	ev->what = PROC_EVENT_FORK;
 85	rcu_read_lock();
 86	parent = rcu_dereference(task->real_parent);
 87	ev->event_data.fork.parent_pid = parent->pid;
 88	ev->event_data.fork.parent_tgid = parent->tgid;
 89	rcu_read_unlock();
 90	ev->event_data.fork.child_pid = task->pid;
 91	ev->event_data.fork.child_tgid = task->tgid;
 92
 93	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
 94	msg->ack = 0; /* not used */
 95	msg->len = sizeof(*ev);
 96	msg->flags = 0; /* not used */
 97	/*  If cn_netlink_send() failed, the data is not sent */
 98	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 99}
100
101void proc_exec_connector(struct task_struct *task)
102{
103	struct cn_msg *msg;
104	struct proc_event *ev;
105	struct timespec ts;
106	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
107
108	if (atomic_read(&proc_event_num_listeners) < 1)
109		return;
110
111	msg = buffer_to_cn_msg(buffer);
112	ev = (struct proc_event *)msg->data;
113	memset(&ev->event_data, 0, sizeof(ev->event_data));
114	get_seq(&msg->seq, &ev->cpu);
115	ktime_get_ts(&ts); /* get high res monotonic timestamp */
116	ev->timestamp_ns = timespec_to_ns(&ts);
117	ev->what = PROC_EVENT_EXEC;
118	ev->event_data.exec.process_pid = task->pid;
119	ev->event_data.exec.process_tgid = task->tgid;
120
121	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
122	msg->ack = 0; /* not used */
123	msg->len = sizeof(*ev);
124	msg->flags = 0; /* not used */
125	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
126}
127
128void proc_id_connector(struct task_struct *task, int which_id)
129{
130	struct cn_msg *msg;
131	struct proc_event *ev;
132	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
133	struct timespec ts;
134	const struct cred *cred;
135
136	if (atomic_read(&proc_event_num_listeners) < 1)
137		return;
138
139	msg = buffer_to_cn_msg(buffer);
140	ev = (struct proc_event *)msg->data;
141	memset(&ev->event_data, 0, sizeof(ev->event_data));
142	ev->what = which_id;
143	ev->event_data.id.process_pid = task->pid;
144	ev->event_data.id.process_tgid = task->tgid;
145	rcu_read_lock();
146	cred = __task_cred(task);
147	if (which_id == PROC_EVENT_UID) {
148		ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid);
149		ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid);
150	} else if (which_id == PROC_EVENT_GID) {
151		ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid);
152		ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid);
153	} else {
154		rcu_read_unlock();
155		return;
156	}
157	rcu_read_unlock();
158	get_seq(&msg->seq, &ev->cpu);
159	ktime_get_ts(&ts); /* get high res monotonic timestamp */
160	ev->timestamp_ns = timespec_to_ns(&ts);
161
162	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
163	msg->ack = 0; /* not used */
164	msg->len = sizeof(*ev);
165	msg->flags = 0; /* not used */
166	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
167}
168
169void proc_sid_connector(struct task_struct *task)
170{
171	struct cn_msg *msg;
172	struct proc_event *ev;
173	struct timespec ts;
174	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
175
176	if (atomic_read(&proc_event_num_listeners) < 1)
177		return;
178
179	msg = buffer_to_cn_msg(buffer);
180	ev = (struct proc_event *)msg->data;
181	memset(&ev->event_data, 0, sizeof(ev->event_data));
182	get_seq(&msg->seq, &ev->cpu);
183	ktime_get_ts(&ts); /* get high res monotonic timestamp */
184	ev->timestamp_ns = timespec_to_ns(&ts);
185	ev->what = PROC_EVENT_SID;
186	ev->event_data.sid.process_pid = task->pid;
187	ev->event_data.sid.process_tgid = task->tgid;
188
189	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
190	msg->ack = 0; /* not used */
191	msg->len = sizeof(*ev);
192	msg->flags = 0; /* not used */
193	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
194}
195
196void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
197{
198	struct cn_msg *msg;
199	struct proc_event *ev;
200	struct timespec ts;
201	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
202
203	if (atomic_read(&proc_event_num_listeners) < 1)
204		return;
205
206	msg = buffer_to_cn_msg(buffer);
207	ev = (struct proc_event *)msg->data;
208	memset(&ev->event_data, 0, sizeof(ev->event_data));
209	get_seq(&msg->seq, &ev->cpu);
210	ktime_get_ts(&ts); /* get high res monotonic timestamp */
211	ev->timestamp_ns = timespec_to_ns(&ts);
212	ev->what = PROC_EVENT_PTRACE;
213	ev->event_data.ptrace.process_pid  = task->pid;
214	ev->event_data.ptrace.process_tgid = task->tgid;
215	if (ptrace_id == PTRACE_ATTACH) {
216		ev->event_data.ptrace.tracer_pid  = current->pid;
217		ev->event_data.ptrace.tracer_tgid = current->tgid;
218	} else if (ptrace_id == PTRACE_DETACH) {
219		ev->event_data.ptrace.tracer_pid  = 0;
220		ev->event_data.ptrace.tracer_tgid = 0;
221	} else
222		return;
223
224	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
225	msg->ack = 0; /* not used */
226	msg->len = sizeof(*ev);
227	msg->flags = 0; /* not used */
228	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
229}
230
231void proc_comm_connector(struct task_struct *task)
232{
233	struct cn_msg *msg;
234	struct proc_event *ev;
235	struct timespec ts;
236	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
237
238	if (atomic_read(&proc_event_num_listeners) < 1)
239		return;
240
241	msg = buffer_to_cn_msg(buffer);
242	ev = (struct proc_event *)msg->data;
243	memset(&ev->event_data, 0, sizeof(ev->event_data));
244	get_seq(&msg->seq, &ev->cpu);
245	ktime_get_ts(&ts); /* get high res monotonic timestamp */
246	ev->timestamp_ns = timespec_to_ns(&ts);
247	ev->what = PROC_EVENT_COMM;
248	ev->event_data.comm.process_pid  = task->pid;
249	ev->event_data.comm.process_tgid = task->tgid;
250	get_task_comm(ev->event_data.comm.comm, task);
251
252	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
253	msg->ack = 0; /* not used */
254	msg->len = sizeof(*ev);
255	msg->flags = 0; /* not used */
256	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
257}
258
259void proc_coredump_connector(struct task_struct *task)
260{
261	struct cn_msg *msg;
262	struct proc_event *ev;
263	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
264	struct timespec ts;
265
266	if (atomic_read(&proc_event_num_listeners) < 1)
267		return;
268
269	msg = buffer_to_cn_msg(buffer);
270	ev = (struct proc_event *)msg->data;
271	memset(&ev->event_data, 0, sizeof(ev->event_data));
272	get_seq(&msg->seq, &ev->cpu);
273	ktime_get_ts(&ts); /* get high res monotonic timestamp */
274	ev->timestamp_ns = timespec_to_ns(&ts);
275	ev->what = PROC_EVENT_COREDUMP;
276	ev->event_data.coredump.process_pid = task->pid;
277	ev->event_data.coredump.process_tgid = task->tgid;
278
279	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
280	msg->ack = 0; /* not used */
281	msg->len = sizeof(*ev);
282	msg->flags = 0; /* not used */
283	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
284}
285
286void proc_exit_connector(struct task_struct *task)
287{
288	struct cn_msg *msg;
289	struct proc_event *ev;
290	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
291	struct timespec ts;
292
293	if (atomic_read(&proc_event_num_listeners) < 1)
294		return;
295
296	msg = buffer_to_cn_msg(buffer);
297	ev = (struct proc_event *)msg->data;
298	memset(&ev->event_data, 0, sizeof(ev->event_data));
299	get_seq(&msg->seq, &ev->cpu);
300	ktime_get_ts(&ts); /* get high res monotonic timestamp */
301	ev->timestamp_ns = timespec_to_ns(&ts);
302	ev->what = PROC_EVENT_EXIT;
303	ev->event_data.exit.process_pid = task->pid;
304	ev->event_data.exit.process_tgid = task->tgid;
305	ev->event_data.exit.exit_code = task->exit_code;
306	ev->event_data.exit.exit_signal = task->exit_signal;
307
308	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
309	msg->ack = 0; /* not used */
310	msg->len = sizeof(*ev);
311	msg->flags = 0; /* not used */
312	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
313}
314
315/*
316 * Send an acknowledgement message to userspace
317 *
318 * Use 0 for success, EFOO otherwise.
319 * Note: this is the negative of conventional kernel error
320 * values because it's not being returned via syscall return
321 * mechanisms.
322 */
323static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
324{
325	struct cn_msg *msg;
326	struct proc_event *ev;
327	__u8 buffer[CN_PROC_MSG_SIZE] __aligned(8);
328	struct timespec ts;
329
330	if (atomic_read(&proc_event_num_listeners) < 1)
331		return;
332
333	msg = buffer_to_cn_msg(buffer);
334	ev = (struct proc_event *)msg->data;
335	memset(&ev->event_data, 0, sizeof(ev->event_data));
336	msg->seq = rcvd_seq;
337	ktime_get_ts(&ts); /* get high res monotonic timestamp */
338	ev->timestamp_ns = timespec_to_ns(&ts);
339	ev->cpu = -1;
340	ev->what = PROC_EVENT_NONE;
341	ev->event_data.ack.err = err;
342	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
343	msg->ack = rcvd_ack + 1;
344	msg->len = sizeof(*ev);
345	msg->flags = 0; /* not used */
346	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
347}
348
349/**
350 * cn_proc_mcast_ctl
351 * @data: message sent from userspace via the connector
352 */
353static void cn_proc_mcast_ctl(struct cn_msg *msg,
354			      struct netlink_skb_parms *nsp)
355{
356	enum proc_cn_mcast_op *mc_op = NULL;
357	int err = 0;
358
359	if (msg->len != sizeof(*mc_op))
360		return;
361
362	/* 
363	 * Events are reported with respect to the initial pid
364	 * and user namespaces so ignore requestors from
365	 * other namespaces.
366	 */
367	if ((current_user_ns() != &init_user_ns) ||
368	    (task_active_pid_ns(current) != &init_pid_ns))
369		return;
370
371	/* Can only change if privileged. */
372	if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) {
373		err = EPERM;
374		goto out;
375	}
376
377	mc_op = (enum proc_cn_mcast_op *)msg->data;
378	switch (*mc_op) {
379	case PROC_CN_MCAST_LISTEN:
380		atomic_inc(&proc_event_num_listeners);
381		break;
382	case PROC_CN_MCAST_IGNORE:
383		atomic_dec(&proc_event_num_listeners);
384		break;
385	default:
386		err = EINVAL;
387		break;
388	}
389
390out:
391	cn_proc_ack(err, msg->seq, msg->ack);
392}
393
394/*
395 * cn_proc_init - initialization entry point
396 *
397 * Adds the connector callback to the connector driver.
398 */
399static int __init cn_proc_init(void)
400{
401	int err = cn_add_callback(&cn_proc_event_id,
402				  "cn_proc",
403				  &cn_proc_mcast_ctl);
404	if (err) {
405		pr_warn("cn_proc failed to register\n");
406		return err;
407	}
408	return 0;
409}
410
411module_init(cn_proc_init);