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