| /* |
| * 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/ktime.h> |
| #include <linux/init.h> |
| #include <linux/connector.h> |
| #include <linux/gfp.h> |
| #include <linux/ptrace.h> |
| #include <linux/atomic.h> |
| #include <linux/pid_namespace.h> |
| |
| #include <linux/cn_proc.h> |
| |
| /* |
| * Size of a cn_msg followed by a proc_event structure. Since the |
| * sizeof struct cn_msg is a multiple of 4 bytes, but not 8 bytes, we |
| * add one 4-byte word to the size here, and then start the actual |
| * cn_msg structure 4 bytes into the stack buffer. The result is that |
| * the immediately following proc_event structure is aligned to 8 bytes. |
| */ |
| #define CN_PROC_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct proc_event) + 4) |
| |
| /* See comment above; we test our assumption about sizeof struct cn_msg here. */ |
| static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer) |
| { |
| BUILD_BUG_ON(sizeof(struct cn_msg) != 20); |
| return (struct cn_msg *)(buffer + 4); |
| } |
| |
| 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_event_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) |
| { |
| preempt_disable(); |
| *ts = __this_cpu_inc_return(proc_event_counts) - 1; |
| *cpu = smp_processor_id(); |
| preempt_enable(); |
| } |
| |
| void proc_fork_connector(struct task_struct *task) |
| { |
| struct cn_msg *msg; |
| struct proc_event *ev; |
| __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8); |
| struct timespec ts; |
| struct task_struct *parent; |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| get_seq(&msg->seq, &ev->cpu); |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| ev->what = PROC_EVENT_FORK; |
| rcu_read_lock(); |
| parent = rcu_dereference(task->real_parent); |
| ev->event_data.fork.parent_pid = parent->pid; |
| ev->event_data.fork.parent_tgid = parent->tgid; |
| rcu_read_unlock(); |
| 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); |
| msg->flags = 0; /* not used */ |
| /* If cn_netlink_send() failed, the data is not sent */ |
| cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL); |
| } |
| |
| void proc_exec_connector(struct task_struct *task) |
| { |
| struct cn_msg *msg; |
| struct proc_event *ev; |
| struct timespec ts; |
| __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8); |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| get_seq(&msg->seq, &ev->cpu); |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| 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); |
| msg->flags = 0; /* not used */ |
| cn_netlink_send(msg, 0, 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] __aligned(8); |
| struct timespec ts; |
| const struct cred *cred; |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| ev->what = which_id; |
| ev->event_data.id.process_pid = task->pid; |
| ev->event_data.id.process_tgid = task->tgid; |
| rcu_read_lock(); |
| cred = __task_cred(task); |
| if (which_id == PROC_EVENT_UID) { |
| ev->event_data.id.r.ruid = from_kuid_munged(&init_user_ns, cred->uid); |
| ev->event_data.id.e.euid = from_kuid_munged(&init_user_ns, cred->euid); |
| } else if (which_id == PROC_EVENT_GID) { |
| ev->event_data.id.r.rgid = from_kgid_munged(&init_user_ns, cred->gid); |
| ev->event_data.id.e.egid = from_kgid_munged(&init_user_ns, cred->egid); |
| } else { |
| rcu_read_unlock(); |
| return; |
| } |
| rcu_read_unlock(); |
| get_seq(&msg->seq, &ev->cpu); |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| |
| memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); |
| msg->ack = 0; /* not used */ |
| msg->len = sizeof(*ev); |
| msg->flags = 0; /* not used */ |
| cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL); |
| } |
| |
| void proc_sid_connector(struct task_struct *task) |
| { |
| struct cn_msg *msg; |
| struct proc_event *ev; |
| struct timespec ts; |
| __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8); |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| get_seq(&msg->seq, &ev->cpu); |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| ev->what = PROC_EVENT_SID; |
| ev->event_data.sid.process_pid = task->pid; |
| ev->event_data.sid.process_tgid = task->tgid; |
| |
| memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); |
| msg->ack = 0; /* not used */ |
| msg->len = sizeof(*ev); |
| msg->flags = 0; /* not used */ |
| cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL); |
| } |
| |
| void proc_ptrace_connector(struct task_struct *task, int ptrace_id) |
| { |
| struct cn_msg *msg; |
| struct proc_event *ev; |
| struct timespec ts; |
| __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8); |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| get_seq(&msg->seq, &ev->cpu); |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| ev->what = PROC_EVENT_PTRACE; |
| ev->event_data.ptrace.process_pid = task->pid; |
| ev->event_data.ptrace.process_tgid = task->tgid; |
| if (ptrace_id == PTRACE_ATTACH) { |
| ev->event_data.ptrace.tracer_pid = current->pid; |
| ev->event_data.ptrace.tracer_tgid = current->tgid; |
| } else if (ptrace_id == PTRACE_DETACH) { |
| ev->event_data.ptrace.tracer_pid = 0; |
| ev->event_data.ptrace.tracer_tgid = 0; |
| } else |
| return; |
| |
| memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); |
| msg->ack = 0; /* not used */ |
| msg->len = sizeof(*ev); |
| msg->flags = 0; /* not used */ |
| cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL); |
| } |
| |
| void proc_comm_connector(struct task_struct *task) |
| { |
| struct cn_msg *msg; |
| struct proc_event *ev; |
| struct timespec ts; |
| __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8); |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| get_seq(&msg->seq, &ev->cpu); |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| ev->what = PROC_EVENT_COMM; |
| ev->event_data.comm.process_pid = task->pid; |
| ev->event_data.comm.process_tgid = task->tgid; |
| get_task_comm(ev->event_data.comm.comm, task); |
| |
| memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); |
| msg->ack = 0; /* not used */ |
| msg->len = sizeof(*ev); |
| msg->flags = 0; /* not used */ |
| cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL); |
| } |
| |
| void proc_coredump_connector(struct task_struct *task) |
| { |
| struct cn_msg *msg; |
| struct proc_event *ev; |
| __u8 buffer[CN_PROC_MSG_SIZE] __aligned(8); |
| struct timespec ts; |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| get_seq(&msg->seq, &ev->cpu); |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| ev->what = PROC_EVENT_COREDUMP; |
| ev->event_data.coredump.process_pid = task->pid; |
| ev->event_data.coredump.process_tgid = task->tgid; |
| |
| memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); |
| msg->ack = 0; /* not used */ |
| msg->len = sizeof(*ev); |
| msg->flags = 0; /* not used */ |
| cn_netlink_send(msg, 0, 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] __aligned(8); |
| struct timespec ts; |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| get_seq(&msg->seq, &ev->cpu); |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| 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); |
| msg->flags = 0; /* not used */ |
| cn_netlink_send(msg, 0, 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] __aligned(8); |
| struct timespec ts; |
| |
| if (atomic_read(&proc_event_num_listeners) < 1) |
| return; |
| |
| msg = buffer_to_cn_msg(buffer); |
| ev = (struct proc_event *)msg->data; |
| memset(&ev->event_data, 0, sizeof(ev->event_data)); |
| msg->seq = rcvd_seq; |
| ktime_get_ts(&ts); /* get high res monotonic timestamp */ |
| ev->timestamp_ns = timespec_to_ns(&ts); |
| 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); |
| msg->flags = 0; /* not used */ |
| cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL); |
| } |
| |
| /** |
| * cn_proc_mcast_ctl |
| * @data: message sent from userspace via the connector |
| */ |
| static void cn_proc_mcast_ctl(struct cn_msg *msg, |
| struct netlink_skb_parms *nsp) |
| { |
| enum proc_cn_mcast_op *mc_op = NULL; |
| int err = 0; |
| |
| if (msg->len != sizeof(*mc_op)) |
| return; |
| |
| /* |
| * Events are reported with respect to the initial pid |
| * and user namespaces so ignore requestors from |
| * other namespaces. |
| */ |
| if ((current_user_ns() != &init_user_ns) || |
| (task_active_pid_ns(current) != &init_pid_ns)) |
| return; |
| |
| /* Can only change if privileged. */ |
| if (!__netlink_ns_capable(nsp, &init_user_ns, CAP_NET_ADMIN)) { |
| err = EPERM; |
| goto out; |
| } |
| |
| 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; |
| } |
| |
| out: |
| 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 = cn_add_callback(&cn_proc_event_id, |
| "cn_proc", |
| &cn_proc_mcast_ctl); |
| if (err) { |
| pr_warn("cn_proc failed to register\n"); |
| return err; |
| } |
| return 0; |
| } |
| |
| module_init(cn_proc_init); |