diff options
Diffstat (limited to 'drivers/connector/cn_proc.c')
-rw-r--r-- | drivers/connector/cn_proc.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c new file mode 100644 index 000000000000..fcdf0fff13a6 --- /dev/null +++ b/drivers/connector/cn_proc.c @@ -0,0 +1,222 @@ +/* + * cn_proc.c - process events connector + * + * Copyright (C) Matt Helsley, IBM Corp. 2005 + * Based on cn_fork.c by Guillaume Thouvenin <guillaume.thouvenin@bull.net> + * Original copyright notice follows: + * Copyright (C) 2005 BULL SA. + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <asm/atomic.h> + +#include <linux/cn_proc.h> + +#define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event)) + +static atomic_t proc_event_num_listeners = ATOMIC_INIT(0); +static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC }; + +/* proc_counts is used as the sequence number of the netlink message */ +static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 }; + +static inline void get_seq(__u32 *ts, int *cpu) +{ + *ts = get_cpu_var(proc_event_counts)++; + *cpu = smp_processor_id(); + put_cpu_var(proc_counts); +} + +void proc_fork_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + get_seq(&msg->seq, &ev->cpu); + ev->what = PROC_EVENT_FORK; + ev->event_data.fork.parent_pid = task->real_parent->pid; + ev->event_data.fork.parent_tgid = task->real_parent->tgid; + ev->event_data.fork.child_pid = task->pid; + ev->event_data.fork.child_tgid = task->tgid; + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + /* If cn_netlink_send() failed, the data is not sent */ + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_exec_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + get_seq(&msg->seq, &ev->cpu); + ev->what = PROC_EVENT_EXEC; + ev->event_data.exec.process_pid = task->pid; + ev->event_data.exec.process_tgid = task->tgid; + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_id_connector(struct task_struct *task, int which_id) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + ev->what = which_id; + ev->event_data.id.process_pid = task->pid; + ev->event_data.id.process_tgid = task->tgid; + if (which_id == PROC_EVENT_UID) { + ev->event_data.id.r.ruid = task->uid; + ev->event_data.id.e.euid = task->euid; + } else if (which_id == PROC_EVENT_GID) { + ev->event_data.id.r.rgid = task->gid; + ev->event_data.id.e.egid = task->egid; + } else + return; + get_seq(&msg->seq, &ev->cpu); + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +void proc_exit_connector(struct task_struct *task) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + get_seq(&msg->seq, &ev->cpu); + ev->what = PROC_EVENT_EXIT; + ev->event_data.exit.process_pid = task->pid; + ev->event_data.exit.process_tgid = task->tgid; + ev->event_data.exit.exit_code = task->exit_code; + ev->event_data.exit.exit_signal = task->exit_signal; + + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = 0; /* not used */ + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +/* + * Send an acknowledgement message to userspace + * + * Use 0 for success, EFOO otherwise. + * Note: this is the negative of conventional kernel error + * values because it's not being returned via syscall return + * mechanisms. + */ +static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack) +{ + struct cn_msg *msg; + struct proc_event *ev; + __u8 buffer[CN_PROC_MSG_SIZE]; + + if (atomic_read(&proc_event_num_listeners) < 1) + return; + + msg = (struct cn_msg*)buffer; + ev = (struct proc_event*)msg->data; + msg->seq = rcvd_seq; + ev->cpu = -1; + ev->what = PROC_EVENT_NONE; + ev->event_data.ack.err = err; + memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); + msg->ack = rcvd_ack + 1; + msg->len = sizeof(*ev); + cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL); +} + +/** + * cn_proc_mcast_ctl + * @data: message sent from userspace via the connector + */ +static void cn_proc_mcast_ctl(void *data) +{ + struct cn_msg *msg = data; + enum proc_cn_mcast_op *mc_op = NULL; + int err = 0; + + if (msg->len != sizeof(*mc_op)) + return; + + mc_op = (enum proc_cn_mcast_op*)msg->data; + switch (*mc_op) { + case PROC_CN_MCAST_LISTEN: + atomic_inc(&proc_event_num_listeners); + break; + case PROC_CN_MCAST_IGNORE: + atomic_dec(&proc_event_num_listeners); + break; + default: + err = EINVAL; + break; + } + cn_proc_ack(err, msg->seq, msg->ack); +} + +/* + * cn_proc_init - initialization entry point + * + * Adds the connector callback to the connector driver. + */ +static int __init cn_proc_init(void) +{ + int err; + + if ((err = cn_add_callback(&cn_proc_event_id, "cn_proc", + &cn_proc_mcast_ctl))) { + printk(KERN_WARNING "cn_proc failed to register\n"); + return err; + } + return 0; +} + +module_init(cn_proc_init); |