ip_auth.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* Copyright (C) 1998-2003 by Darren Reed & Guido van Rooij.
*
* See the IPFILTER.LICENCE file for details on licencing.
*/
#if defined(KERNEL) || defined(_KERNEL)
# undef KERNEL
# undef _KERNEL
# define KERNEL 1
# define _KERNEL 1
#endif
#include <sys/errno.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/file.h>
#if !defined(_KERNEL)
# include <stdio.h>
# include <stdlib.h>
# include <string.h>
# define _KERNEL
# ifdef __OpenBSD__
struct file;
# endif
# include <sys/uio.h>
# undef _KERNEL
#endif
#if defined(_KERNEL) && (__FreeBSD_version >= 220000)
# include <sys/filio.h>
# include <sys/fcntl.h>
#else
# include <sys/ioctl.h>
#endif
#include <sys/protosw.h>
#include <sys/socket.h>
#if defined(_KERNEL)
# include <sys/systm.h>
# if !defined(__SVR4) && !defined(__svr4__)
# include <sys/mbuf.h>
# endif
#endif
#if defined(__SVR4) || defined(__svr4__)
# include <sys/filio.h>
# include <sys/byteorder.h>
# ifdef _KERNEL
# include <sys/dditypes.h>
# endif
# include <sys/stream.h>
# include <sys/kmem.h>
#endif
#if (_BSDI_VERSION >= 199802) || (__FreeBSD_version >= 400000)
# include <sys/queue.h>
#endif
#if defined(__NetBSD__) || defined(__OpenBSD__) || defined(bsdi)
# include <machine/cpu.h>
#endif
#if defined(_KERNEL) && defined(__NetBSD__) && (__NetBSD_Version__ >= 104000000)
# include <sys/proc.h>
#endif
#include <net/if.h>
#ifdef sun
# include <net/af.h>
#endif
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#if !defined(_KERNEL) && !defined(__osf__)
# define KERNEL
# define _KERNEL
# define NOT_KERNEL
#endif
#include <netinet/ip_var.h>
#ifdef NOT_KERNEL
# undef _KERNEL
# undef KERNEL
#endif
#ifdef __sgi
# ifdef IFF_DRVRLOCK /* IRIX6 */
# include <sys/hashing.h>
# endif
#endif
#include <netinet/tcp.h>
#if defined(__sgi) && !defined(IFF_DRVRLOCK) /* IRIX < 6 */
extern struct ifqueue ipintrq; /* ip packet input queue */
#else
# if !defined(__hpux)
# if __FreeBSD_version >= 300000
# include <net/if_var.h>
# if __FreeBSD_version >= 500042
# define IF_QFULL _IF_QFULL
# define IF_DROP _IF_DROP
# endif /* __FreeBSD_version >= 500042 */
# endif
# include <netinet/in_var.h>
# include <netinet/tcp_fsm.h>
# endif
#endif
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include <netinet/tcpip.h>
#if SOLARIS2 >= 10
#include "ip_compat.h"
#include "ip_fil.h"
#include "ip_auth.h"
#else
#include "netinet/ip_compat.h"
#include "netinet/ip_fil.h"
#include "netinet/ip_auth.h"
#endif
#if !defined(MENTAT)
# include <net/netisr.h>
# ifdef __FreeBSD__
# include <machine/cpufunc.h>
# endif
#endif
#if (__FreeBSD_version >= 300000)
# include <sys/malloc.h>
# if defined(_KERNEL) && !defined(IPFILTER_LKM)
# include <sys/libkern.h>
# include <sys/systm.h>
# endif
#endif
#if !defined(lint)
static const char rcsid[] = "@(#)$Id: ip_auth.c,v 2.56 2003/06/28 17:01:55 darrenr Exp $";
#endif
#ifdef USE_MUTEXES
extern ipfrwlock_t ipf_auth;
extern ipfmutex_t ipf_authmx;
# if SOLARIS
extern kcondvar_t ipfauthwait;
# endif /* SOLARIS */
#endif /* USE_MUTEXES */
int fr_authsize = FR_NUMAUTH;
int fr_authused = 0;
int fr_defaultauthage = 600;
int fr_auth_lock = 0;
int fr_auth_init = 0;
fr_authstat_t fr_authstats;
static frauth_t *fr_auth = NULL;
mb_t **fr_authpkts = NULL;
int fr_authstart = 0, fr_authend = 0, fr_authnext = 0;
frauthent_t *fae_list = NULL;
frentry_t *ipauth = NULL,
*fr_authlist = NULL;
int fr_authinit()
{
KMALLOCS(fr_auth, frauth_t *, fr_authsize * sizeof(*fr_auth));
if (fr_auth != NULL)
bzero((char *)fr_auth, fr_authsize * sizeof(*fr_auth));
else
return -1;
KMALLOCS(fr_authpkts, mb_t **, fr_authsize * sizeof(*fr_authpkts));
if (fr_authpkts != NULL)
bzero((char *)fr_authpkts, fr_authsize * sizeof(*fr_authpkts));
else
return -1;
MUTEX_INIT(&ipf_authmx, "ipf auth log mutex");
RWLOCK_INIT(&ipf_auth, "ipf IP User-Auth rwlock");
#if SOLARIS && defined(_KERNEL)
cv_init(&ipfauthwait, "ipf auth condvar", CV_DRIVER, NULL);
#endif
fr_auth_init = 1;
return 0;
}
/*
* Check if a packet has authorization. If the packet is found to match an
* authorization result and that would result in a feedback loop (i.e. it
* will end up returning FR_AUTH) then return FR_BLOCK instead.
*/
frentry_t *fr_checkauth(fin, passp)
fr_info_t *fin;
u_32_t *passp;
{
frentry_t *fr;
frauth_t *fra;
u_32_t pass;
u_short id;
ip_t *ip;
int i;
if (fr_auth_lock || !fr_authused)
return NULL;
ip = fin->fin_ip;
id = ip->ip_id;
READ_ENTER(&ipf_auth);
for (i = fr_authstart; i != fr_authend; ) {
/*
* index becomes -2 only after an SIOCAUTHW. Check this in
* case the same packet gets sent again and it hasn't yet been
* auth'd.
*/
fra = fr_auth + i;
if ((fra->fra_index == -2) && (id == fra->fra_info.fin_id) &&
!bcmp((char *)fin, (char *)&fra->fra_info, FI_CSIZE)) {
/*
* Avoid feedback loop.
*/
if (!(pass = fra->fra_pass) || (FR_ISAUTH(pass)))
pass = FR_BLOCK;
/*
* Create a dummy rule for the stateful checking to
* use and return. Zero out any values we don't
* trust from userland!
*/
if ((pass & FR_KEEPSTATE) || ((pass & FR_KEEPFRAG) &&
(fin->fin_flx & FI_FRAG))) {
KMALLOC(fr, frentry_t *);
if (fr) {
bcopy((char *)fra->fra_info.fin_fr,
(char *)fr, sizeof(*fr));
fr->fr_grp = NULL;
fr->fr_ifa = fin->fin_ifp;
fr->fr_func = NULL;
fr->fr_ref = 1;
fr->fr_flags = pass;
fr->fr_ifas[1] = NULL;
fr->fr_ifas[2] = NULL;
fr->fr_ifas[3] = NULL;
}
} else
fr = fra->fra_info.fin_fr;
fin->fin_fr = fr;
RWLOCK_EXIT(&ipf_auth);
WRITE_ENTER(&ipf_auth);
if ((fr != NULL) && (fr != fra->fra_info.fin_fr)) {
fr->fr_next = fr_authlist;
fr_authlist = fr;
}
fr_authstats.fas_hits++;
fra->fra_index = -1;
fr_authused--;
if (i == fr_authstart) {
while (fra->fra_index == -1) {
i++;
fra++;
if (i == fr_authsize) {
i = 0;
fra = fr_auth;
}
fr_authstart = i;
if (i == fr_authend)
break;
}
if (fr_authstart == fr_authend) {
fr_authnext = 0;
fr_authstart = fr_authend = 0;
}
}
RWLOCK_EXIT(&ipf_auth);
if (passp != NULL)
*passp = pass;
ATOMIC_INCL(fr_authstats.fas_hits);
return fr;
}
i++;
if (i == fr_authsize)
i = 0;
}
fr_authstats.fas_miss++;
RWLOCK_EXIT(&ipf_auth);
ATOMIC_INCL(fr_authstats.fas_miss);
return NULL;
}
/*
* Check if we have room in the auth array to hold details for another packet.
* If we do, store it and wake up any user programs which are waiting to
* hear about these events.
*/
int fr_newauth(m, fin)
mb_t *m;
fr_info_t *fin;
{
#if defined(_KERNEL) && defined(MENTAT)
qif_t *qif = fin->fin_qif;
#endif
frauth_t *fra;
#if !defined(sparc) && !defined(m68k)
ip_t *ip;
#endif
int i;
if (fr_auth_lock)
return 0;
WRITE_ENTER(&ipf_auth);
if (fr_authstart > fr_authend) {
fr_authstats.fas_nospace++;
RWLOCK_EXIT(&ipf_auth);
return 0;
} else {
if (fr_authused == fr_authsize) {
fr_authstats.fas_nospace++;
RWLOCK_EXIT(&ipf_auth);
return 0;
}
}
fr_authstats.fas_added++;
fr_authused++;
i = fr_authend++;
if (fr_authend == fr_authsize)
fr_authend = 0;
RWLOCK_EXIT(&ipf_auth);
fra = fr_auth + i;
fra->fra_index = i;
fra->fra_pass = 0;
fra->fra_age = fr_defaultauthage;
bcopy((char *)fin, (char *)&fra->fra_info, sizeof(*fin));
#if !defined(sparc) && !defined(m68k)
/*
* No need to copyback here as we want to undo the changes, not keep
* them.
*/
ip = fin->fin_ip;
# if defined(MENTAT) && defined(_KERNEL)
if ((ip == (ip_t *)m->b_rptr) && (fin->fin_v == 4))
# endif
{
register u_short bo;
bo = ip->ip_len;
ip->ip_len = htons(bo);
bo = ip->ip_off;
ip->ip_off = htons(bo);
}
#endif
#if SOLARIS && defined(_KERNEL)
m->b_rptr -= qif->qf_off;
fr_authpkts[i] = *(mblk_t **)fin->fin_mp;
fra->fra_q = qif->qf_q;
cv_signal(&ipfauthwait);
#else
# if defined(BSD) && !defined(sparc) && (BSD >= 199306)
if (!fin->fin_out) {
ip->ip_len = htons(ip->ip_len);
ip->ip_off = htons(ip->ip_off);
}
# endif
fr_authpkts[i] = m;
WAKEUP(&fr_authnext);
#endif
return 1;
}
int fr_auth_ioctl(data, cmd, mode)
caddr_t data;
#if defined(__NetBSD__) || defined(__OpenBSD__) || \
(_BSDI_VERSION >= 199701) || (__FreeBSD_version >= 300003)
u_long cmd;
#else
int cmd;
#endif
int mode;
{
mb_t *m;
#if defined(_KERNEL) && !defined(MENTAT)
struct ifqueue *ifq;
# ifdef USE_SPL
int s;
# endif /* USE_SPL */
#endif
frauth_t auth, *au = &auth, *fra;
int i, error = 0, len;
char *t;
switch (cmd)
{
case SIOCSTLCK :
if (!(mode & FWRITE)) {
error = EPERM;
break;
}
error = fr_lock(data, &fr_auth_lock);
break;
case SIOCATHST:
fr_authstats.fas_faelist = fae_list;
error = fr_outobj(data, &fr_authstats, IPFOBJ_AUTHSTAT);
break;
case SIOCIPFFL:
SPL_NET(s);
WRITE_ENTER(&ipf_auth);
i = fr_authflush();
RWLOCK_EXIT(&ipf_auth);
SPL_X(s);
error = copyoutptr((char *)&i, data, sizeof(i));
break;
case SIOCAUTHW:
fr_authioctlloop:
error = fr_inobj(data, au, IPFOBJ_FRAUTH);
READ_ENTER(&ipf_auth);
if ((fr_authnext != fr_authend) && fr_authpkts[fr_authnext]) {
error = fr_outobj(data, &fr_auth[fr_authnext],
IPFOBJ_FRAUTH);
if (auth.fra_len != 0 && auth.fra_buf != NULL) {
/*
* Copy packet contents out to user space if
* requested. Bail on an error.
*/
m = fr_authpkts[fr_authnext];
len = MSGDSIZE(m);
if (len > auth.fra_len)
len = auth.fra_len;
auth.fra_len = len;
for (t = auth.fra_buf; m && (len > 0); ) {
i = MIN(M_LEN(m), len);
error = copyoutptr(MTOD(m, char *),
t, i);
len -= i;
t += i;
if (error != 0)
break;
}
}
RWLOCK_EXIT(&ipf_auth);
if (error != 0)
break;
SPL_NET(s);
WRITE_ENTER(&ipf_auth);
fr_authnext++;
if (fr_authnext == fr_authsize)
fr_authnext = 0;
RWLOCK_EXIT(&ipf_auth);
SPL_X(s);
return 0;
}
RWLOCK_EXIT(&ipf_auth);
/*
* We exit ipf_global here because a program that enters in
* here will have a lock on it and goto sleep having this lock.
* If someone were to do an 'ipf -D' the system would then
* deadlock. The catch with releasing it here is that the
* caller of this function expects it to be held when we
* return so we have to reacquire it in here.
*/
RWLOCK_EXIT(&ipf_global);
MUTEX_ENTER(&ipf_authmx);
#ifdef _KERNEL
# if SOLARIS
error = 0;
if (!cv_wait_sig(&ipfauthwait, &ipf_authmx.ipf_lk))
error = EINTR;
# else /* SOLARIS */
# ifdef __hpux
{
lock_t *l;
l = get_sleep_lock(&fr_authnext);
error = sleep(&fr_authnext, PZERO+1);
spinunlock(l);
}
# else
# ifdef __osf__
error = mpsleep(&fr_authnext, PSUSP|PCATCH, "fr_authnext", 0,
&ipf_authmx, MS_LOCK_SIMPLE);
# else
error = SLEEP(&fr_authnext, "fr_authnext");
# endif /* __osf__ */
# endif /* __hpux */
# endif /* SOLARIS */
#endif
MUTEX_EXIT(&ipf_authmx);
READ_ENTER(&ipf_global);
if (error == 0) {
READ_ENTER(&ipf_auth);
goto fr_authioctlloop;
}
break;
case SIOCAUTHR:
error = fr_inobj(data, &auth, IPFOBJ_FRAUTH);
if (error != 0)
return error;
SPL_NET(s);
WRITE_ENTER(&ipf_auth);
i = au->fra_index;
fra = fr_auth + i;
if ((i < 0) || (i >= fr_authsize) ||
(fra->fra_info.fin_id != au->fra_info.fin_id)) {
RWLOCK_EXIT(&ipf_auth);
SPL_X(s);
return ESRCH;
}
m = fr_authpkts[i];
fra->fra_index = -2;
fra->fra_pass = au->fra_pass;
fr_authpkts[i] = NULL;
RWLOCK_EXIT(&ipf_auth);
#ifdef _KERNEL
if ((m != NULL) && (au->fra_info.fin_out != 0)) {
# ifdef MENTAT
error = !putq(fra->fra_q, m);
# else /* MENTAT */
# if (_BSDI_VERSION >= 199802) || defined(__OpenBSD__) || \
(defined(__sgi) && (IRIX >= 605) || \
(defined(__FreeBSD__) && (__FreeBSD_version >= 500043)))
error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL,
NULL);
# else
error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL);
# endif
# endif /* MENTAT */
if (error != 0)
fr_authstats.fas_sendfail++;
else
fr_authstats.fas_sendok++;
} else if (m) {
# ifdef MENTAT
error = !putq(fra->fra_q, m);
# else /* MENTAT */
ifq = &ipintrq;
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
m_freem(m);
error = ENOBUFS;
} else {
IF_ENQUEUE(ifq, m);
# if IRIX < 605
schednetisr(NETISR_IP);
# endif
}
# endif /* MENTAT */
if (error != 0)
fr_authstats.fas_quefail++;
else
fr_authstats.fas_queok++;
} else
error = EINVAL;
# ifdef MENTAT
if (error != 0)
error = EINVAL;
# else /* MENTAT */
/*
* If we experience an error which will result in the packet
* not being processed, make sure we advance to the next one.
*/
if (error == ENOBUFS) {
fr_authused--;
fra->fra_index = -1;
fra->fra_pass = 0;
if (i == fr_authstart) {
while (fra->fra_index == -1) {
i++;
if (i == fr_authsize)
i = 0;
fr_authstart = i;
if (i == fr_authend)
break;
}
if (fr_authstart == fr_authend) {
fr_authnext = 0;
fr_authstart = fr_authend = 0;
}
}
}
# endif /* MENTAT */
#endif /* _KERNEL */
SPL_X(s);
break;
default :
error = EINVAL;
break;
}
return error;
}
/*
* Free all network buffer memory used to keep saved packets.
*/
void fr_authunload()
{
register int i;
register frauthent_t *fae, **faep;
frentry_t *fr, **frp;
mb_t *m;
if (fr_auth != NULL) {
KFREES(fr_auth, fr_authsize * sizeof(*fr_auth));
fr_auth = NULL;
}
if (fr_authpkts != NULL) {
for (i = 0; i < fr_authsize; i++) {
m = fr_authpkts[i];
if (m != NULL) {
FREE_MB_T(m);
fr_authpkts[i] = NULL;
}
}
KFREES(fr_authpkts, fr_authsize * sizeof(*fr_authpkts));
fr_authpkts = NULL;
}
faep = &fae_list;
while ((fae = *faep) != NULL) {
*faep = fae->fae_next;
KFREE(fae);
}
ipauth = NULL;
if (fr_authlist != NULL) {
for (frp = &fr_authlist; ((fr = *frp) != NULL); ) {
if (fr->fr_ref == 1) {
*frp = fr->fr_next;
KFREE(fr);
} else
frp = &fr->fr_next;
}
}
if (fr_auth_init == 1) {
# if SOLARIS && defined(_KERNEL)
cv_destroy(&ipfauthwait);
# endif
MUTEX_DESTROY(&ipf_authmx);
RW_DESTROY(&ipf_auth);
fr_auth_init = 0;
}
}
/*
* Slowly expire held auth records. Timeouts are set
* in expectation of this being called twice per second.
*/
void fr_authexpire()
{
register int i;
register frauth_t *fra;
register frauthent_t *fae, **faep;
register frentry_t *fr, **frp;
mb_t *m;
# if !defined(MENAT) && defined(_KERNEL) && defined(USE_SPL)
int s;
# endif
if (fr_auth_lock)
return;
SPL_NET(s);
WRITE_ENTER(&ipf_auth);
for (i = 0, fra = fr_auth; i < fr_authsize; i++, fra++) {
fra->fra_age--;
if ((fra->fra_age == 0) && (m = fr_authpkts[i])) {
FREE_MB_T(m);
fr_authpkts[i] = NULL;
fr_auth[i].fra_index = -1;
fr_authstats.fas_expire++;
fr_authused--;
}
}
for (faep = &fae_list; ((fae = *faep) != NULL); ) {
fae->fae_age--;
if (fae->fae_age == 0) {
*faep = fae->fae_next;
KFREE(fae);
fr_authstats.fas_expire++;
} else
faep = &fae->fae_next;
}
if (fae_list != NULL)
ipauth = &fae_list->fae_fr;
else
ipauth = NULL;
for (frp = &fr_authlist; ((fr = *frp) != NULL); ) {
if (fr->fr_ref == 1) {
*frp = fr->fr_next;
KFREE(fr);
} else
frp = &fr->fr_next;
}
RWLOCK_EXIT(&ipf_auth);
SPL_X(s);
}
int fr_preauthcmd(cmd, fr, frptr)
#if defined(__NetBSD__) || defined(__OpenBSD__) || \
(_BSDI_VERSION >= 199701) || (__FreeBSD_version >= 300000)
u_long cmd;
#else
int cmd;
#endif
frentry_t *fr, **frptr;
{
frauthent_t *fae, **faep;
int error = 0;
# if !defined(MENAT) && defined(_KERNEL) && defined(USE_SPL)
int s;
#endif
if ((cmd != SIOCADAFR) && (cmd != SIOCRMAFR))
return EIO;
for (faep = &fae_list; ((fae = *faep) != NULL); ) {
if (&fae->fae_fr == fr)
break;
else
faep = &fae->fae_next;
}
if (cmd == SIOCRMAFR) {
if (fr == NULL || frptr == NULL)
error = EINVAL;
else if (fae == NULL)
error = ESRCH;
else {
SPL_NET(s);
WRITE_ENTER(&ipf_auth);
*faep = fae->fae_next;
if (ipauth == &fae->fae_fr)
ipauth = fae_list ? &fae_list->fae_fr : NULL;
RWLOCK_EXIT(&ipf_auth);
SPL_X(s);
KFREE(fae);
}
} else if (fr != NULL && frptr != NULL) {
KMALLOC(fae, frauthent_t *);
if (fae != NULL) {
bcopy((char *)fr, (char *)&fae->fae_fr,
sizeof(*fr));
SPL_NET(s);
WRITE_ENTER(&ipf_auth);
fae->fae_age = fr_defaultauthage;
fae->fae_fr.fr_hits = 0;
fae->fae_fr.fr_next = *frptr;
*frptr = &fae->fae_fr;
fae->fae_next = *faep;
*faep = fae;
ipauth = &fae_list->fae_fr;
RWLOCK_EXIT(&ipf_auth);
SPL_X(s);
} else
error = ENOMEM;
} else
error = EINVAL;
return error;
}
/*
* Flush held packets.
* Must already be properly SPL'ed and Locked on &ipf_auth.
*
*/
int fr_authflush()
{
register int i, num_flushed;
mb_t *m;
if (fr_auth_lock)
return -1;
num_flushed = 0;
for (i = 0 ; i < fr_authsize; i++) {
m = fr_authpkts[i];
if (m != NULL) {
FREE_MB_T(m);
fr_authpkts[i] = NULL;
fr_auth[i].fra_index = -1;
/* perhaps add & use a flush counter inst.*/
fr_authstats.fas_expire++;
fr_authused--;
num_flushed++;
}
}
fr_authstart = 0;
fr_authend = 0;
fr_authnext = 0;
return num_flushed;
}