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 <asm/atomic.h> 31#include <asm/unaligned.h> 32 33#include <linux/cn_proc.h> 34 35#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event)) 36 37static atomic_t proc_event_num_listeners = ATOMIC_INIT(0); 38static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC }; 39 40/* proc_event_counts is used as the sequence number of the netlink message */ 41static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 }; 42 43static inline void get_seq(__u32 *ts, int *cpu) 44{ 45 *ts = get_cpu_var(proc_event_counts)++; 46 *cpu = smp_processor_id(); 47 put_cpu_var(proc_event_counts); 48} 49 50void proc_fork_connector(struct task_struct *task) 51{ 52 struct cn_msg *msg; 53 struct proc_event *ev; 54 __u8 buffer[CN_PROC_MSG_SIZE]; 55 struct timespec ts; 56 57 if (atomic_read(&proc_event_num_listeners) < 1) 58 return; 59 60 msg = (struct cn_msg*)buffer; 61 ev = (struct proc_event*)msg->data; 62 get_seq(&msg->seq, &ev->cpu); 63 ktime_get_ts(&ts); /* get high res monotonic timestamp */ 64 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); 65 ev->what = PROC_EVENT_FORK; 66 ev->event_data.fork.parent_pid = task->real_parent->pid; 67 ev->event_data.fork.parent_tgid = task->real_parent->tgid; 68 ev->event_data.fork.child_pid = task->pid; 69 ev->event_data.fork.child_tgid = task->tgid; 70 71 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); 72 msg->ack = 0; /* not used */ 73 msg->len = sizeof(*ev); 74 /* If cn_netlink_send() failed, the data is not sent */ 75 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); 76} 77 78void proc_exec_connector(struct task_struct *task) 79{ 80 struct cn_msg *msg; 81 struct proc_event *ev; 82 struct timespec ts; 83 __u8 buffer[CN_PROC_MSG_SIZE]; 84 85 if (atomic_read(&proc_event_num_listeners) < 1) 86 return; 87 88 msg = (struct cn_msg*)buffer; 89 ev = (struct proc_event*)msg->data; 90 get_seq(&msg->seq, &ev->cpu); 91 ktime_get_ts(&ts); /* get high res monotonic timestamp */ 92 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); 93 ev->what = PROC_EVENT_EXEC; 94 ev->event_data.exec.process_pid = task->pid; 95 ev->event_data.exec.process_tgid = task->tgid; 96 97 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); 98 msg->ack = 0; /* not used */ 99 msg->len = sizeof(*ev); 100 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); 101} 102 103void proc_id_connector(struct task_struct *task, int which_id) 104{ 105 struct cn_msg *msg; 106 struct proc_event *ev; 107 __u8 buffer[CN_PROC_MSG_SIZE]; 108 struct timespec ts; 109 110 if (atomic_read(&proc_event_num_listeners) < 1) 111 return; 112 113 msg = (struct cn_msg*)buffer; 114 ev = (struct proc_event*)msg->data; 115 ev->what = which_id; 116 ev->event_data.id.process_pid = task->pid; 117 ev->event_data.id.process_tgid = task->tgid; 118 if (which_id == PROC_EVENT_UID) { 119 ev->event_data.id.r.ruid = task->uid; 120 ev->event_data.id.e.euid = task->euid; 121 } else if (which_id == PROC_EVENT_GID) { 122 ev->event_data.id.r.rgid = task->gid; 123 ev->event_data.id.e.egid = task->egid; 124 } else 125 return; 126 get_seq(&msg->seq, &ev->cpu); 127 ktime_get_ts(&ts); /* get high res monotonic timestamp */ 128 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); 129 130 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); 131 msg->ack = 0; /* not used */ 132 msg->len = sizeof(*ev); 133 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); 134} 135 136void proc_exit_connector(struct task_struct *task) 137{ 138 struct cn_msg *msg; 139 struct proc_event *ev; 140 __u8 buffer[CN_PROC_MSG_SIZE]; 141 struct timespec ts; 142 143 if (atomic_read(&proc_event_num_listeners) < 1) 144 return; 145 146 msg = (struct cn_msg*)buffer; 147 ev = (struct proc_event*)msg->data; 148 get_seq(&msg->seq, &ev->cpu); 149 ktime_get_ts(&ts); /* get high res monotonic timestamp */ 150 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); 151 ev->what = PROC_EVENT_EXIT; 152 ev->event_data.exit.process_pid = task->pid; 153 ev->event_data.exit.process_tgid = task->tgid; 154 ev->event_data.exit.exit_code = task->exit_code; 155 ev->event_data.exit.exit_signal = task->exit_signal; 156 157 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); 158 msg->ack = 0; /* not used */ 159 msg->len = sizeof(*ev); 160 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); 161} 162 163/* 164 * Send an acknowledgement message to userspace 165 * 166 * Use 0 for success, EFOO otherwise. 167 * Note: this is the negative of conventional kernel error 168 * values because it's not being returned via syscall return 169 * mechanisms. 170 */ 171static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack) 172{ 173 struct cn_msg *msg; 174 struct proc_event *ev; 175 __u8 buffer[CN_PROC_MSG_SIZE]; 176 struct timespec ts; 177 178 if (atomic_read(&proc_event_num_listeners) < 1) 179 return; 180 181 msg = (struct cn_msg*)buffer; 182 ev = (struct proc_event*)msg->data; 183 msg->seq = rcvd_seq; 184 ktime_get_ts(&ts); /* get high res monotonic timestamp */ 185 put_unaligned(timespec_to_ns(&ts), (__u64 *)&ev->timestamp_ns); 186 ev->cpu = -1; 187 ev->what = PROC_EVENT_NONE; 188 ev->event_data.ack.err = err; 189 memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); 190 msg->ack = rcvd_ack + 1; 191 msg->len = sizeof(*ev); 192 cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); 193} 194 195/** 196 * cn_proc_mcast_ctl 197 * @data: message sent from userspace via the connector 198 */ 199static void cn_proc_mcast_ctl(void *data) 200{ 201 struct cn_msg *msg = data; 202 enum proc_cn_mcast_op *mc_op = NULL; 203 int err = 0; 204 205 if (msg->len != sizeof(*mc_op)) 206 return; 207 208 mc_op = (enum proc_cn_mcast_op*)msg->data; 209 switch (*mc_op) { 210 case PROC_CN_MCAST_LISTEN: 211 atomic_inc(&proc_event_num_listeners); 212 break; 213 case PROC_CN_MCAST_IGNORE: 214 atomic_dec(&proc_event_num_listeners); 215 break; 216 default: 217 err = EINVAL; 218 break; 219 } 220 cn_proc_ack(err, msg->seq, msg->ack); 221} 222 223/* 224 * cn_proc_init - initialization entry point 225 * 226 * Adds the connector callback to the connector driver. 227 */ 228static int __init cn_proc_init(void) 229{ 230 int err; 231 232 if ((err = cn_add_callback(&cn_proc_event_id, "cn_proc", 233 &cn_proc_mcast_ctl))) { 234 printk(KERN_WARNING "cn_proc failed to register\n"); 235 return err; 236 } 237 return 0; 238} 239 240module_init(cn_proc_init); 241