/* auditsc.c -- System-call auditing support
* Handles all system-call specific auditing features.
*
* Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
* All Rights Reserved.
*
* 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
*
* Written by Rickard E. (Rik) Faith <faith@redhat.com>
*
* Many of the ideas implemented here are from Stephen C. Tweedie,
* especially the idea of avoiding a copy by using getname.
*
* The method for actual interception of syscall entry and exit (not in
* this file -- see entry.S) is based on a GPL'd patch written by
* okir@suse.de and Copyright 2003 SuSE Linux AG.
*
*/
#include <linux/init.h>
#include <asm/types.h>
#include <asm/atomic.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/mount.h>
#include <linux/socket.h>
#include <linux/audit.h>
#include <linux/personality.h>
#include <linux/time.h>
#include <linux/kthread.h>
#include <linux/netlink.h>
#include <linux/compiler.h>
#include <asm/unistd.h>
/* 0 = no checking
1 = put_count checking
2 = verbose put_count checking
*/
#define AUDIT_DEBUG 0
/* No syscall auditing will take place unless audit_enabled != 0. */
extern int audit_enabled;
/* AUDIT_NAMES is the number of slots we reserve in the audit_context
* for saving names from getname(). */
#define AUDIT_NAMES 20
/* AUDIT_NAMES_RESERVED is the number of slots we reserve in the
* audit_context from being used for nameless inodes from
* path_lookup. */
#define AUDIT_NAMES_RESERVED 7
/* At task start time, the audit_state is set in the audit_context using
a per-task filter. At syscall entry, the audit_state is augmented by
the syscall filter. */
enum audit_state {
AUDIT_DISABLED, /* Do not create per-task audit_context.
* No syscall-specific audit records can
* be generated. */
AUDIT_SETUP_CONTEXT, /* Create the per-task audit_context,
* but don't necessarily fill it in at
* syscall entry time (i.e., filter
* instead). */
AUDIT_BUILD_CONTEXT, /* Create the per-task audit_context,
* and always fill it in at syscall
* entry time. This makes a full
* syscall record available if some
* other part of the kernel decides it
* should be recorded. */
AUDIT_RECORD_CONTEXT /* Create the per-task audit_context,
* always fill it in at syscall entry
* time, and always write out the audit
* record at syscall exit time. */
};
/* When fs/namei.c:getname() is called, we store the pointer in name and
* we don't let putname() free it (instead we free all of the saved
* pointers at syscall exit time).
*
* Further, in fs/namei.c:path_lookup() we store the inode and device. */
struct audit_names {
const char *name;
unsigned long ino;
dev_t dev;
umode_t mode;
uid_t uid;
gid_t gid;
dev_t rdev;
unsigned flags;
};
struct audit_aux_data {
struct audit_aux_data *next;
int type;
};
#define AUDIT_AUX_IPCPERM 0
struct audit_aux_data_ipcctl {
struct audit_aux_data d;
struct ipc_perm p;
unsigned long qbytes;
uid_t uid;
gid_t gid;
mode_t mode;
};
struct audit_aux_data_socketcall {
struct audit_aux_data d;
int nargs;
unsigned long args[0];
};
struct audit_aux_data_sockaddr {
struct audit_aux_data d;
int len;
char a[0];
};
struct audit_aux_data_path {
struct audit_aux_data d;
struct dentry *dentry;
struct vfsmount *mnt;
};
/* The per-task audit context. */
struct audit_context {
int in_syscall