blob: cc055b2913c0e9f11482b9199356655891a4d2ea [file] [log] [blame] [raw]
/*
* Copyright (C) 1993-2001 by Darren Reed.
*
* See the IPFILTER.LICENCE file for details on licencing.
*
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/exec.h>
#include <sys/mbuf.h>
#include <net/if.h>
#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <net/route.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcpip.h>
#include <sys/lkm.h>
#include "ipl.h"
#include "ip_compat.h"
#include "ip_fil.h"
#define vn_lock(v,f) VOP_LOCK(v)
#if !defined(VOP_LEASE) && defined(LEASE_CHECK)
#define VOP_LEASE LEASE_CHECK
#endif
extern int lkmenodev(void);
#if OpenBSD >= 200311
int if_ipf_lkmentry(struct lkm_table *, int, int);
#else
int if_ipf(struct lkm_table *, int, int);
#endif
static int ipf_unload(void);
static int ipf_load(void);
static int ipf_remove(void);
static int ipfaction(struct lkm_table *, int);
static char *ipf_devfiles[] = { IPL_NAME, IPNAT_NAME, IPSTATE_NAME,
IPAUTH_NAME, IPSYNC_NAME, IPSCAN_NAME,
IPLOOKUP_NAME, NULL };
struct cdevsw ipfdevsw =
{
ipfopen, /* open */
ipfclose, /* close */
ipfread, /* read */
(void *)nullop, /* write */
ipfioctl, /* ioctl */
(void *)nullop, /* stop */
(void *)NULL, /* tty */
(void *)nullop, /* select */
(void *)nullop, /* mmap */
NULL /* strategy */
};
int ipf_major = 0;
MOD_DEV(IPL_VERSION, LM_DT_CHAR, -1, &ipfdevsw);
extern int vd_unuseddev(void);
extern struct cdevsw cdevsw[];
extern int nchrdev;
#if OpenBSD >= 200311
int if_ipf_lkmentry (lkmtp, cmd, ver)
#else
int if_ipf(lkmtp, cmd, ver)
#endif
struct lkm_table *lkmtp;
int cmd, ver;
{
DISPATCH(lkmtp, cmd, ver, ipfaction, ipfaction, ipfaction);
}
int lkmexists(struct lkm_table *); /* defined in /sys/kern/kern_lkm.c */
static int ipfaction(lkmtp, cmd)
struct lkm_table *lkmtp;
int cmd;
{
int i;
struct lkm_dev *args = lkmtp->private.lkm_dev;
int err = 0;
switch (cmd)
{
case LKM_E_LOAD :
if (lkmexists(lkmtp))
return EEXIST;
for (i = 0; i < nchrdev; i++)
if (cdevsw[i].d_open == (dev_type_open((*)))lkmenodev ||
cdevsw[i].d_open == ipfopen)
break;
if (i == nchrdev) {
printf("IP Filter: No free cdevsw slots\n");
return ENODEV;
}
ipf_major = i;
args->lkm_offset = i; /* slot in cdevsw[] */
printf("IP Filter: loaded into slot %d\n", ipf_major);
return ipf_load();
case LKM_E_UNLOAD :
err = ipf_unload();
if (!err)
printf("IP Filter: unloaded from slot %d\n",
ipf_major);
break;
case LKM_E_STAT :
break;
default:
err = EIO;
break;
}
return err;
}
static int ipf_remove()
{
struct nameidata nd;
int error, i;
char *name;
for (i = 0; (name = ipf_devfiles[i]); i++) {
#if OpenBSD >= 200311
NDINIT(&nd, DELETE, LOCKPARENT | LOCKLEAF, UIO_SYSSPACE,
name, curproc);
#else
NDINIT(&nd, DELETE, LOCKPARENT, UIO_SYSSPACE, name, curproc);
#endif
if ((error = namei(&nd)))
return (error);
VOP_LEASE(nd.ni_vp, curproc, curproc->p_ucred, LEASE_WRITE);
#if OpenBSD < 200311
VOP_LOCK(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY, curproc);
VOP_LEASE(nd.ni_dvp, curproc, curproc->p_ucred, LEASE_WRITE);
#else
(void)uvm_vnp_uncache(nd.ni_vp);
VOP_LEASE(nd.ni_dvp, curproc, curproc->p_ucred, LEASE_WRITE);
VOP_LEASE(nd.ni_vp, curproc, curproc->p_ucred, LEASE_WRITE);
#endif
(void) VOP_REMOVE(nd.ni_dvp, nd.ni_vp, &nd.ni_cnd);
}
return 0;
}
static int ipf_unload()
{
int error = 0;
/*
* Unloading - remove the filter rule check from the IP
* input/output stream.
*/
if (ipf_refcnt)
error = EBUSY;
else if (ipf_running >= 0)
error = ipfdetach();
if (error == 0) {
ipf_running = -2;
error = ipf_remove();
printf("%s unloaded\n", ipfilter_version);
}
return error;
}
static int ipf_load()
{
struct nameidata nd;
struct vattr vattr;
int error = 0, fmode = S_IFCHR|0600, i;
char *name;
/*
* XXX Remove existing device nodes prior to creating new ones
* XXX using the assigned LKM device slot's major number. In a
* XXX perfect world we could use the ones specified by cdevsw[].
*/
(void)ipf_remove();
error = ipfattach();
for (i = 0; (error == 0) && (name = ipf_devfiles[i]); i++) {
NDINIT(&nd, CREATE, LOCKPARENT, UIO_SYSSPACE, name, curproc);
if ((error = namei(&nd)))
break;
if (nd.ni_vp != NULL) {
VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
if (nd.ni_dvp == nd.ni_vp)
vrele(nd.ni_dvp);
else
vput(nd.ni_dvp);
vrele(nd.ni_vp);
error = EEXIST;
break;
}
VATTR_NULL(&vattr);
vattr.va_type = VCHR;
vattr.va_mode = (fmode & 07777);
vattr.va_rdev = (ipf_major << 8) | i;
VOP_LEASE(nd.ni_dvp, curproc, curproc->p_ucred, LEASE_WRITE);
error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
}
if (error == 0) {
char *defpass;
if (FR_ISPASS(ipf_pass))
defpass = "pass";
else if (FR_ISBLOCK(ipf_pass))
defpass = "block";
else
defpass = "no-match -> block";
printf("%s initialized. Default = %s all, Logging = %s%s\n",
ipfilter_version, defpass,
#ifdef IPFILTER_LOG
"enabled",
#else
"disabled",
#endif
#ifdef IPFILTER_COMPILED
" (COMPILED)"
#else
""
#endif
);
ipf_running = 1;
}
return error;
}
/*
* routines below for saving IP headers to buffer
*/
int
ipfopen(dev, flags, devtype, p)
dev_t dev;
int flags;
int devtype;
struct proc *p;
{
u_int min = GET_MINOR(dev);
int error;
if (IPL_LOGMAX < min) {
error = ENXIO;
} else {
switch (unit)
{
case IPL_LOGIPF :
case IPL_LOGNAT :
case IPL_LOGSTATE :
case IPL_LOGAUTH :
case IPL_LOGLOOKUP :
case IPL_LOGSYNC :
#ifdef IPFILTER_SCAN
case IPL_LOGSCAN :
#endif
error = 0;
break;
default :
error = ENXIO;
break;
}
}
return error;
}
int
ipfclose(dev, flags, devtype, p)
dev_t dev;
int flags;
int devtype;
struct proc *p;
{
u_int min = GET_MINOR(dev);
if (IPL_LOGMAX < min)
min = ENXIO;
else
min = 0;
return min;
}
/*
* ipfread/ipflog
* both of these must operate with at least splnet() lest they be
* called during packet processing and cause an inconsistancy to appear in
* the filter lists.
*/
int
ipfread(dev, uio, ioflag)
dev_t dev;
register struct uio *uio;
int ioflag;
{
if (ipf_running < 1)
return EIO;
if (GET_MINOR(dev) == IPL_LOGSYNC)
return ipfsync_read(uio);
#ifdef IPFILTER_LOG
return ipflog_read(GET_MINOR(dev), uio);
#else
return ENXIO;
#endif
}
/*
* ipfwrite
* both of these must operate with at least splnet() lest they be
* called during packet processing and cause an inconsistancy to appear in
* the filter lists.
*/
int
#if (BSD >= 199306)
ipfwrite(dev, uio, ioflag)
int ioflag;
#else
ipfwrite(dev, uio)
#endif
dev_t dev;
register struct uio *uio;
{
if (ipf_running < 1)
return EIO;
if (GET_MINOR(dev) == IPL_LOGSYNC)
return ipfsync_write(uio);
return ENXIO;
}