/*
* Copyright (C) 1993-2003 by Darren Reed.
*
* See the IPFILTER.LICENCE file for details on licencing.
*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#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>
#ifdef __hpux
# include <sys/timeout.h>
#endif
#if !defined(_KERNEL)
# include <stdio.h>
# include <string.h>
# include <stdlib.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
#if !defined(linux)
# include <sys/protosw.h>
#endif
#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__)
# if defined(_KERNEL) && !defined(__sgi) && !defined(AIX)
# include <sys/kernel.h>
# endif
#else
# include <sys/byteorder.h>
# ifdef _KERNEL
# include <sys/dditypes.h>
# endif
# include <sys/stream.h>
# include <sys/kmem.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(linux)
# include <netinet/ip_var.h>
#endif
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include "netinet/ip_compat.h"
#include <netinet/tcpip.h>
#include "netinet/ip_fil.h"
#include "netinet/ip_nat.h"
#include "netinet/ip_frag.h"
#include "netinet/ip_state.h"
#include "netinet/ip_auth.h"
#include "netinet/ipf_stack.h"
#if (__FreeBSD_version >= 300000)
# include <sys/malloc.h>
# if defined(_KERNEL)
# ifndef IPFILTER_LKM
# include <sys/libkern.h>
# include <sys/systm.h>
# endif
extern struct callout_handle fr_slowtimer_ch;
# endif
#endif
#if defined(__NetBSD__) && (__NetBSD_Version__ >= 104230000)
# include <sys/callout.h>
extern struct callout fr_slowtimer_ch;
#endif
#if defined(__OpenBSD__)
# include <sys/timeout.h>
extern struct timeout fr_slowtimer_ch;
#endif
/* END OF INCLUDES */
#if !defined(lint)
static const char sccsid[] = "@(#)ip_frag.c 1.11 3/24/96 (C) 1993-2000 Darren Reed";
static const char rcsid[] = "@(#)$Id: ip_frag.c,v 2.77.2.5 2005/08/11 14:33:10 darrenr Exp $";
#endif
static INLINE int ipfr_index __P((fr_info_t *, ipfr_t *));
static ipfr_t *ipfr_newfrag __P((fr_info_t *, u_32_t, ipfr_t **));
static ipfr_t *fr_fraglookup __P((fr_info_t *, ipfr_t **));
static void fr_fragdelete __P((ipfr_t *, ipfr_t ***, ipf_stack_t *));
/* ------------------------------------------------------------------------ */
/* Function: fr_fraginit */
/* Returns: int - 0 == success, -1 == error */
/* Parameters: Nil */
/* */
/* Initialise the hash tables for the fragment cache lookups. */
/* ------------------------------------------------------------------------ */
int fr_fraginit(ifs)
ipf_stack_t *ifs;
{
ifs->ifs_ipfr_tail = &ifs->ifs_ipfr_list;
ifs->ifs_ipfr_nattail = &ifs->ifs_ipfr_natlist;
ifs->ifs_ipfr_ipidtail = &ifs->ifs_ipfr_ipidlist;
/* the IP frag related variables are set in ipftuneable_setdefs() to
* their default values
*/
KMALLOCS(ifs->ifs_ipfr_heads, ipfr_t **,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
if (ifs->ifs_ipfr_heads == NULL)
return -1;
bzero((char *)ifs->ifs_ipfr_heads,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
KMALLOCS(ifs->ifs_ipfr_nattab, ipfr_t **,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
if (ifs->ifs_ipfr_nattab == NULL)
return -1;
bzero((char *)ifs->ifs_ipfr_nattab,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
KMALLOCS(ifs->ifs_ipfr_ipidtab, ipfr_t **,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
if (ifs->ifs_ipfr_ipidtab == NULL)
return -1;
bzero((char *)ifs->ifs_ipfr_ipidtab,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
RWLOCK_INIT(&ifs->ifs_ipf_frag, "ipf fragment rwlock");
/* Initialise frblock with "block in all" */
bzero((char *)&ifs->ifs_frblock, sizeof(ifs->ifs_frblock));
ifs->ifs_frblock.fr_flags = FR_BLOCK|FR_INQUE; /* block in */
ifs->ifs_frblock.fr_ref = 1;
ifs->ifs_fr_frag_init = 1;
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_fragunload */
/* Returns: Nil */
/* Parameters: Nil */
/* */
/* Free all memory allocated whilst running and from initialisation. */
/* ------------------------------------------------------------------------ */
void fr_fragunload(ifs)
ipf_stack_t *ifs;
{
if (ifs->ifs_fr_frag_init == 1) {
fr_fragclear(ifs);
RW_DESTROY(&ifs->ifs_ipf_frag);
ifs->ifs_fr_frag_init = 0;
}
if (ifs->ifs_ipfr_heads != NULL) {
KFREES(ifs->ifs_ipfr_heads,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
}
ifs->ifs_ipfr_heads = NULL;
if (ifs->ifs_ipfr_nattab != NULL) {
KFREES(ifs->ifs_ipfr_nattab,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
}
ifs->ifs_ipfr_nattab = NULL;
if (ifs->ifs_ipfr_ipidtab != NULL) {
KFREES(ifs->ifs_ipfr_ipidtab,
ifs->ifs_ipfr_size * sizeof(ipfr_t *));
}
ifs->ifs_ipfr_ipidtab = NULL;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_fragstats */
/* Returns: ipfrstat_t* - pointer to struct with current frag stats */
/* Parameters: Nil */
/* */
/* Updates ipfr_stats with current information and returns a pointer to it */
/* ------------------------------------------------------------------------ */
ipfrstat_t *fr_fragstats(ifs)
ipf_stack_t *ifs;
{
ifs->ifs_ipfr_stats.ifs_table = ifs->ifs_ipfr_heads;
ifs->ifs_ipfr_stats.ifs_nattab = ifs->ifs_ipfr_nattab;
ifs->ifs_ipfr_stats.ifs_inuse = ifs->ifs_ipfr_inuse;
return &ifs->ifs_ipfr_stats;
}
/* ------------------------------------------------------------------------ */
/* Function: ipfr_index */
/* Returns: int - index in fragment table for given packet */
/* Parameters: fin(I) - pointer to packet information */
/* frag(O) - pointer to ipfr_t structure to fill */
/* */
/* Compute the index in the fragment table while filling the per packet */
/* part of the fragment state. */
/* ------------------------------------------------------------------------ */
static INLINE int ipfr_index(fin, frag)
fr_info_t *fin;
ipfr_t *frag;
{
u_int idx;
/*
* For fragments, we record protocol, packet id, TOS and both IP#'s
* (these should all be the same for all fragments of a packet).
*
* build up a hash value to index the table with.
*/
#ifdef USE_INET6
if (fin->fin_v == 6) {
ip6_t *ip6 = (ip6_t *)fin->fin_ip;
frag->ipfr_p = fin->fin_fi.fi_p;
frag->ipfr_id = fin->fin_id;
frag->ipfr_tos = ip6->ip6_flow & IPV6_FLOWINFO_MASK;
frag->ipfr_src.in6 = ip6->ip6_src;
frag->ipfr_dst.in6 = ip6->ip6_dst;
} else
#endif
{
ip_t *ip = fin->fin_ip;
frag->ipfr_p = ip->ip_p;
frag->ipfr_id = ip->ip_id;
frag->ipfr_tos = ip->ip_tos;
frag->ipfr_src.in4.s_addr = ip->ip_src.s_addr;
frag->ipfr_src.i6[1] = 0;
frag->ipfr_src.i6[2] = 0;
frag->ipfr_src.i6[3] = 0;
frag->ipfr_dst.in4.s_addr = ip->ip_dst.s_addr;
frag->ipfr_dst.i6[1] = 0;
frag->ipfr_dst.i6[2] = 0;
frag->ipfr_dst.i6[3] = 0;
}
frag->ipfr_ifp = fin->fin_ifp;
frag->ipfr_optmsk = fin->fin_fi.fi_optmsk & IPF_OPTCOPY;
frag->ipfr_secmsk = fin->fin_fi.fi_secmsk;
frag->ipfr_auth = fin->fin_fi.fi_auth;
idx = frag->ipfr_p;
idx += frag->ipfr_id;
idx += frag->ipfr_src.i6[0];
idx += frag->ipfr_src.i6[1];
idx += frag->ipfr_src.i6[2];
idx += frag->ipfr_src.i6[3];
idx += frag->ipfr_dst.i6[0];
idx += frag->ipfr_dst.i6[1];
idx += frag->ipfr_dst.i6[2];
idx += frag->ipfr_dst.i6[3];
idx *= 127;
idx %= IPFT_SIZE;
return idx;
}
/* ------------------------------------------------------------------------ */
/* Function: ipfr_newfrag */
/* Returns: ipfr_t * - pointer to fragment cache state info or NULL */
/* Parameters: fin(I) - pointer to packet information */
/* table(I) - pointer to frag table to add to */
/* */
/* Add a new entry to the fragment cache, registering it as having come */
/* through this box, with the result of the filter operation. */
/* ------------------------------------------------------------------------ */
static ipfr_t *ipfr_newfrag(fin, pass, table)
fr_info_t *fin;
u_32_t pass;
ipfr_t *table[];
{
ipfr_t *fra, frag;
u_int idx, off;
ipf_stack_t *ifs = fin->fin_ifs;
if (ifs->ifs_ipfr_inuse >= ifs->ifs_ipfr_size)
return NULL;
if ((fin->fin_flx & (FI_FRAG|FI_BAD)) != FI_FRAG)
return NULL;
if (pass & FR_FRSTRICT)
if (fin->fin_off != 0)
return NULL;
idx = ipfr_index(fin, &frag);
/*
* first, make sure it isn't already there...
*/
for (fra = table[idx]; (fra != NULL); fra = fra->ipfr_hnext)
if (!bcmp((char *)&frag.ipfr_ifp, (char *)&fra->ipfr_ifp,
IPFR_CMPSZ)) {
ifs->ifs_ipfr_stats.ifs_exists++;
return NULL;
}
/*
* allocate some memory, if possible, if not, just record that we
* failed to do so.
*/
KMALLOC(fra, ipfr_t *);
if (fra == NULL) {
ifs->ifs_ipfr_stats.ifs_nomem++;
return NULL;
}
fra->ipfr_rule = fin->fin_fr;
if (fra->ipfr_rule != NULL) {
frentry_t *fr;
fr = fin->fin_fr;
MUTEX_ENTER(&fr->fr_lock);
fr->fr_ref++;
MUTEX_EXIT(&fr->fr_lock);
}
/*
* Insert the fragment into the fragment table, copy the struct used
* in the search using bcopy rather than reassign each field.
* Set the ttl to the default.
*/
if ((fra->ipfr_hnext = table[idx]) != NULL)
table[idx]->ipfr_hprev = &fra->ipfr_hnext;
fra->ipfr_hprev = table + idx;
fra->ipfr_data = NULL;
table[idx] = fra;
bcopy((char *)&frag.ipfr_ifp, (char *)&fra->ipfr_ifp, IPFR_CMPSZ);
fra->ipfr_ttl = ifs->ifs_fr_ticks + ifs->ifs_fr_ipfrttl;
/*
* Compute the offset of the expected start of the next packet.
*/
off = fin->fin_off >> 3;
if (off == 0) {
fra->ipfr_seen0 = 1;
} else {
fra->ipfr_seen0 = 0;
}
fra->ipfr_off = off + fin->fin_dlen;
fra->ipfr_pass = pass;
fra->ipfr_ref = 1;
ifs->ifs_ipfr_stats.ifs_new++;
ifs->ifs_ipfr_inuse++;
return fra;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_newfrag */
/* Returns: int - 0 == success, -1 == error */
/* Parameters: fin(I) - pointer to packet information */
/* */
/* Add a new entry to the fragment cache table based on the current packet */
/* ------------------------------------------------------------------------ */
int fr_newfrag(fin, pass)
u_32_t pass;
fr_info_t *fin;
{
ipfr_t *fra;
ipf_stack_t *ifs = fin->fin_ifs;
if (ifs->ifs_fr_frag_lock != 0)
return -1;
WRITE_ENTER(&ifs->ifs_ipf_frag);
fra = ipfr_newfrag(fin, pass, ifs->ifs_ipfr_heads);
if (fra != NULL) {
*ifs->ifs_ipfr_tail = fra;
fra->ipfr_prev = ifs->ifs_ipfr_tail;
ifs->ifs_ipfr_tail = &fra->ipfr_next;
if (ifs->ifs_ipfr_list == NULL)
ifs->ifs_ipfr_list = fra;
fra->ipfr_next = NULL;
}
RWLOCK_EXIT(&ifs->ifs_ipf_frag);
return fra ? 0 : -1;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_nat_newfrag */
/* Returns: int - 0 == success, -1 == error */
/* Parameters: fin(I) - pointer to packet information */
/* nat(I) - pointer to NAT structure */
/* */
/* Create a new NAT fragment cache entry based on the current packet and */
/* the NAT structure for this "session". */
/* ------------------------------------------------------------------------ */
int fr_nat_newfrag(fin, pass, nat)
fr_info_t *fin;
u_32_t pass;
nat_t *nat;
{
ipfr_t *fra;
ipf_stack_t *ifs = fin->fin_ifs;
if (ifs->ifs_fr_frag_lock != 0)
return 0;
WRITE_ENTER(&ifs->ifs_ipf_natfrag);
fra = ipfr_newfrag(fin, pass, ifs->ifs_ipfr_nattab);
if (fra != NULL) {
fra->ipfr_data = nat;
nat->nat_data = fra;
*ifs->ifs_ipfr_nattail = fra;
fra->ipfr_prev = ifs->ifs_ipfr_nattail;
ifs->ifs_ipfr_nattail = &fra->ipfr_next;
fra->ipfr_next = NULL;
}
RWLOCK_EXIT(&ifs->ifs_ipf_natfrag);
return fra ? 0 : -1;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_ipid_newfrag */
/* Returns: int - 0 == success, -1 == error */
/* Parameters: fin(I) - pointer to packet information */
/* ipid(I) - new IP ID for this fragmented packet */
/* */
/* Create a new fragment cache entry for this packet and store, as a data */
/* pointer, the new IP ID value. */
/* ------------------------------------------------------------------------ */
int fr_ipid_newfrag(fin, ipid)
fr_info_t *fin;
u_32_t ipid;
{
ipfr_t *fra;
ipf_stack_t *ifs = fin->fin_ifs;
if (ifs->ifs_fr_frag_lock)
return 0;
WRITE_ENTER(&ifs->ifs_ipf_ipidfrag);
fra = ipfr_newfrag(fin, 0, ifs->ifs_ipfr_ipidtab);
if (fra != NULL) {
fra->ipfr_data = (void *)(uintptr_t)ipid;
*ifs->ifs_ipfr_ipidtail = fra;
fra->ipfr_prev = ifs->ifs_ipfr_ipidtail;
ifs->ifs_ipfr_ipidtail = &fra->ipfr_next;
fra->ipfr_next = NULL;
}
RWLOCK_EXIT(&ifs->ifs_ipf_ipidfrag);
return fra ? 0 : -1;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_fraglookup */
/* Returns: ipfr_t * - pointer to ipfr_t structure if there's a */
/* matching entry in the frag table, else NULL */
/* Parameters: fin(I) - pointer to packet information */
/* table(I) - pointer to fragment cache table to search */
/* */
/* Check the fragment cache to see if there is already a record of this */
/* packet with its filter result known. */
/* ------------------------------------------------------------------------ */
static ipfr_t *fr_fraglookup(fin, table)
fr_info_t *fin;
ipfr_t *table[];
{
ipfr_t *f, frag;
u_int idx;
ipf_stack_t *ifs = fin->fin_ifs;
if ((fin->fin_flx & (FI_FRAG|FI_BAD)) != FI_FRAG)
return NULL;
/*
* For fragments, we record protocol, packet id, TOS and both IP#'s
* (these should all be the same for all fragments of a packet).
*
* build up a hash value to index the table with.
*/
idx = ipfr_index(fin, &frag);
/*
* check the table, careful to only compare the right amount of data
*/
for (f = table[idx]; f; f = f->ipfr_hnext)
if (!bcmp((char *)&frag.ipfr_ifp, (char *)&f->ipfr_ifp,
IPFR_CMPSZ)) {
u_short off;
/*
* We don't want to let short packets match because
* they could be compromising the security of other
* rules that want to match on layer 4 fields (and
* can't because they have been fragmented off.)
* Why do this check here? The counter acts as an
* indicator of this kind of attack, whereas if it was
* elsewhere, it wouldn't know if other matching
* packets had been seen.
*/
if (fin->fin_flx & FI_SHORT) {
ATOMIC_INCL(ifs->ifs_ipfr_stats.ifs_short);
continue;
}
/*
* XXX - We really need to be guarding against the
* retransmission of (src,dst,id,offset-range) here
* because a fragmented packet is never resent with
* the same IP ID# (or shouldn't).
*/
off = fin->fin_off >> 3;
if (f->ipfr_seen0) {
if (off == 0) {
ATOMIC_INCL(ifs->ifs_ipfr_stats.ifs_retrans0);
continue;
}
} else if (off == 0) {
f->ipfr_seen0 = 1;
}
if (f != table[idx]) {
ipfr_t **fp;
/*
* Move fragment info. to the top of the list
* to speed up searches. First, delink...
*/
fp = f->ipfr_hprev;
(*fp) = f->ipfr_hnext;
if (f->ipfr_hnext != NULL)
f->ipfr_hnext->ipfr_hprev = fp;
/*
* Then put back at the top of the chain.
*/
f->ipfr_hnext = table[idx];
table[idx]->ipfr_hprev = &f->ipfr_hnext;
f->ipfr_hprev = table + idx;
table[idx] = f;
}
/*
* If we've follwed the fragments, and this is the
* last (in order), shrink expiration time.
*/
if (off == f->ipfr_off) {
if (!(fin->fin_flx & FI_MOREFRAG))
f->ipfr_ttl = ifs->ifs_fr_ticks + 1;
f->ipfr_off = fin->fin_dlen + off;
} else if (f->ipfr_pass & FR_FRSTRICT)
continue;
ATOMIC_INCL(ifs->ifs_ipfr_stats.ifs_hits);
return f;
}
return NULL;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_nat_knownfrag */
/* Returns: nat_t* - pointer to 'parent' NAT structure if frag table */
/* match found, else NULL */
/* Parameters: fin(I) - pointer to packet information */
/* */
/* Functional interface for NAT lookups of the NAT fragment cache */
/* ------------------------------------------------------------------------ */
nat_t *fr_nat_knownfrag(fin)
fr_info_t *fin;
{
nat_t *nat;
ipfr_t *ipf;
ipf_stack_t *ifs = fin->fin_ifs;
if (ifs->ifs_fr_frag_lock || !ifs->ifs_ipfr_natlist)
return NULL;
READ_ENTER(&ifs->ifs_ipf_natfrag);
ipf = fr_fraglookup(fin, ifs->ifs_ipfr_nattab);
if (ipf != NULL) {
nat = ipf->ipfr_data;
/*
* This is the last fragment for this packet.
*/
if ((ipf->ipfr_ttl == ifs->ifs_fr_ticks + 1) && (nat != NULL)) {
nat->nat_data = NULL;
ipf->ipfr_data = NULL;
}
} else
nat = NULL;
RWLOCK_EXIT(&ifs->ifs_ipf_natfrag);
return nat;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_ipid_knownfrag */
/* Returns: u_32_t - IPv4 ID for this packet if match found, else */
/* return 0xfffffff to indicate no match. */
/* Parameters: fin(I) - pointer to packet information */
/* */
/* Functional interface for IP ID lookups of the IP ID fragment cache */
/* ------------------------------------------------------------------------ */
u_32_t fr_ipid_knownfrag(fin)
fr_info_t *fin;
{
ipfr_t *ipf;
u_32_t id;
ipf_stack_t *ifs = fin->fin_ifs;
if (ifs->ifs_fr_frag_lock || !ifs->ifs_ipfr_ipidlist)
return 0xffffffff;
READ_ENTER(&ifs->ifs_ipf_ipidfrag);
ipf = fr_fraglookup(fin, ifs->ifs_ipfr_ipidtab);
if (ipf != NULL)
id = (u_32_t)(uintptr_t)ipf->ipfr_data;
else
id = 0xffffffff;
RWLOCK_EXIT(&ifs->ifs_ipf_ipidfrag);
return id;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_knownfrag */
/* Returns: frentry_t* - pointer to filter rule if a match is found in */
/* the frag cache table, else NULL. */
/* Parameters: fin(I) - pointer to packet information */
/* passp(O) - pointer to where to store rule flags resturned */
/* */
/* Functional interface for normal lookups of the fragment cache. If a */
/* match is found, return the rule pointer and flags from the rule, except */
/* that if FR_LOGFIRST is set, reset FR_LOG. */
/* ------------------------------------------------------------------------ */
frentry_t *fr_knownfrag(fin, passp)
fr_info_t *fin;
u_32_t *passp;
{
frentry_t *fr = NULL;
ipfr_t *fra;
u_32_t pass, oflx;
ipf_stack_t *ifs = fin->fin_ifs;
if (ifs->ifs_fr_frag_lock || (ifs->ifs_ipfr_list == NULL))
return NULL;
READ_ENTER(&ifs->ifs_ipf_frag);
oflx = fin->fin_flx;
fra = fr_fraglookup(fin, ifs->ifs_ipfr_heads);
if (fra != NULL) {
fr = fra->ipfr_rule;
fin->fin_fr = fr;
if (fr != NULL) {
pass = fr->fr_flags;
if ((pass & FR_LOGFIRST) != 0)
pass &= ~(FR_LOGFIRST|FR_LOG);
*passp = pass;
}
}
if (!(oflx & FI_BAD) && (fin->fin_flx & FI_BAD)) {
*passp &= ~FR_CMDMASK;
*passp |= FR_BLOCK;
fr = &ifs->ifs_frblock;
}
RWLOCK_EXIT(&ifs->ifs_ipf_frag);
return fr;
}
/* ------------------------------------------------------------------------ */
/* Function: fr_forget */
/* Returns: Nil */
/* Parameters: ptr(I) - pointer to data structure */
/* */
/* Search through all of the fragment cache entries and wherever a pointer */
/* is found to match ptr, reset it to NULL. */
/* ------------------------------------------------------------------------ */
void fr_forget(ptr, ifs)
void *ptr;
ipf_stack_t *ifs;
{
ipfr_t *fr;
WRITE_ENTER(&ifs->ifs_ipf_frag);
for (fr = ifs->ifs_ipfr_list; fr; fr = fr->ipfr_next)
if (fr->ipfr_data == ptr)
fr->ipfr_data = NULL;
RWLOCK_EXIT(&ifs->ifs_ipf_frag);
}
/* ------------------------------------------------------------------------ */
/* Function: fr_forgetnat */
/* Returns: Nil */
/* Parameters: ptr(I) - pointer to data structure */
/* */
/* Search through all of the fragment cache entries for NAT and wherever a */
/* pointer is found to match ptr, reset it to NULL. */
/* ------------------------------------------------------------------------ */
void fr_forgetnat(ptr, ifs)
void *ptr;
ipf_stack_t *ifs;
{
ipfr_t *fr;
WRITE_ENTER(&ifs->ifs_ipf_natfrag);
for (fr = ifs->ifs_ipfr_natlist; fr; fr = fr->ipfr_next)
if (fr->ipfr_data == ptr)
fr->ipfr_data = NULL;
RWLOCK_EXIT(&ifs->ifs_ipf_natfrag);
}
/* ------------------------------------------------------------------------ */
/* Function: fr_fragdelete */
/* Returns: Nil */
/* Parameters: fra(I) - pointer to fragment structure to delete */
/* tail(IO) - pointer to the pointer to the tail of the frag */
/* list */
/* */
/* Remove a fragment cache table entry from the table & list. Also free */
/* the filter rule it is associated with it if it is no longer used as a */
/* result of decreasing the reference count. */
/* ------------------------------------------------------------------------ */
static void fr_fragdelete(fra, tail, ifs)
ipfr_t *fra, ***tail;
ipf_stack_t *ifs;
{
frentry_t *fr;
fr = fra->ipfr_rule;
if (fr != NULL)
(void)fr_derefrule(&fr, ifs);
if (fra->ipfr_next)
fra->ipfr_next->ipfr_prev = fra->ipfr_prev;
*fra->ipfr_prev = fra->ipfr_next;
if (*tail == &fra->ipfr_next)
*tail = fra->ipfr_prev;
if (fra->ipfr_hnext)
fra->ipfr_hnext->ipfr_hprev = fra->ipfr_hprev;
*fra->ipfr_hprev = fra->ipfr_hnext;
if (fra->ipfr_ref <= 0)
KFREE(fra);
}
/* ------------------------------------------------------------------------ */
/* Function: fr_fragclear */
/* Returns: Nil */
/* Parameters: Nil */
/* */
/* Free memory in use by fragment state information kept. Do the normal */
/* fragment state stuff first and then the NAT-fragment table. */
/* ------------------------------------------------------------------------ */
void fr_fragclear(ifs)
ipf_stack_t *ifs;
{
ipfr_t *fra;
nat_t *nat;
WRITE_ENTER(&ifs->ifs_ipf_frag);
while ((fra = ifs->ifs_ipfr_list) != NULL) {
fra->ipfr_ref--;
fr_fragdelete(fra, &ifs->ifs_ipfr_tail, ifs);
}
ifs->ifs_ipfr_tail = &ifs->ifs_ipfr_list;
RWLOCK_EXIT(&ifs->ifs_ipf_frag);
WRITE_ENTER(&ifs->ifs_ipf_nat);
WRITE_ENTER(&ifs->ifs_ipf_natfrag);
while ((fra = ifs->ifs_ipfr_natlist) != NULL) {
nat = fra->ipfr_data;
if (nat != NULL) {
if (nat->nat_data == fra)
nat->nat_data = NULL;
}
fra->ipfr_ref--;
fr_fragdelete(fra, &ifs->ifs_ipfr_nattail, ifs);
}
ifs->ifs_ipfr_nattail = &ifs->ifs_ipfr_natlist;
RWLOCK_EXIT(&ifs->ifs_ipf_natfrag);
RWLOCK_EXIT(&ifs->ifs_ipf_nat);
}
/* ------------------------------------------------------------------------ */
/* Function: fr_fragexpire */
/* Returns: Nil */
/* Parameters: Nil */
/* */
/* Expire entries in the fragment cache table that have been there too long */
/* ------------------------------------------------------------------------ */
void fr_fragexpire(ifs)
ipf_stack_t *ifs;
{
ipfr_t **fp, *fra;
nat_t *nat;
SPL_INT(s);
if (ifs->ifs_fr_frag_lock)
return;
SPL_NET(s);
WRITE_ENTER(&ifs->ifs_ipf_frag);
/*
* Go through the entire table, looking for entries to expire,
* which is indicated by the ttl being less than or equal to
* ifs_fr_ticks.
*/
for (fp = &ifs->ifs_ipfr_list; ((fra = *fp) != NULL); ) {
if (fra->ipfr_ttl > ifs->ifs_fr_ticks)
break;
fra->ipfr_ref--;
fr_fragdelete(fra, &ifs->ifs_ipfr_tail, ifs);
ifs->ifs_ipfr_stats.ifs_expire++;
ifs->ifs_ipfr_inuse--;
}
RWLOCK_EXIT(&ifs->ifs_ipf_frag);
WRITE_ENTER(&ifs->ifs_ipf_ipidfrag);
for (fp = &ifs->ifs_ipfr_ipidlist; ((fra = *fp) != NULL); ) {
if (fra->ipfr_ttl > ifs->ifs_fr_ticks)
break;
fra->ipfr_ref--;
fr_fragdelete(fra, &ifs->ifs_ipfr_ipidtail, ifs);
ifs->ifs_ipfr_stats.ifs_expire++;
ifs->ifs_ipfr_inuse--;
}
RWLOCK_EXIT(&ifs->ifs_ipf_ipidfrag);
/*
* Same again for the NAT table, except that if the structure also
* still points to a NAT structure, and the NAT structure points back
* at the one to be free'd, NULL the reference from the NAT struct.
* NOTE: We need to grab both mutex's early, and in this order so as
* to prevent a deadlock if both try to expire at the same time.
*/
WRITE_ENTER(&ifs->ifs_ipf_nat);
WRITE_ENTER(&ifs->ifs_ipf_natfrag);
for (fp = &ifs->ifs_ipfr_natlist; ((fra = *fp) != NULL); ) {
if (fra->ipfr_ttl > ifs->ifs_fr_ticks)
break;
nat = fra->ipfr_data;
if (nat != NULL) {
if (nat->nat_data == fra)
nat->nat_data = NULL;
}
fra->ipfr_ref--;
fr_fragdelete(fra, &ifs->ifs_ipfr_nattail, ifs);
ifs->ifs_ipfr_stats.ifs_expire++;
ifs->ifs_ipfr_inuse--;
}
RWLOCK_EXIT(&ifs->ifs_ipf_natfrag);
RWLOCK_EXIT(&ifs->ifs_ipf_nat);
SPL_X(s);
}
/* ------------------------------------------------------------------------ */
/* Function: fr_slowtimer */
/* Returns: Nil */
/* Parameters: Nil */
/* */
/* Slowly expire held state for fragments. Timeouts are set * in */
/* expectation of this being called twice per second. */
/* ------------------------------------------------------------------------ */
#if !defined(_KERNEL) || (!SOLARIS && !defined(__hpux) && !defined(__sgi) && \
!defined(__osf__) && !defined(linux))
# if defined(_KERNEL) && ((BSD >= 199103) || defined(__sgi))
void fr_slowtimer __P((void *arg))
# else
int fr_slowtimer(void *arg)
# endif
{
ipf_stack_t *ifs = arg;
READ_ENTER(&ifs->ifs_ipf_global);
fr_fragexpire(ifs);
fr_timeoutstate(ifs);
fr_natexpire(ifs);
fr_authexpire(ifs);
ifs->ifs_fr_ticks++;
if (ifs->ifs_fr_running <= 0)
goto done;
# ifdef _KERNEL
# if defined(__NetBSD__) && (__NetBSD_Version__ >= 104240000)
callout_reset(&fr_slowtimer_ch, hz / 2, fr_slowtimer, NULL);
# else
# if defined(__OpenBSD__)
timeout_add(&fr_slowtimer_ch, hz/2);
# else
# if (__FreeBSD_version >= 300000)
fr_slowtimer_ch = timeout(fr_slowtimer, NULL, hz/2);
# else
# ifdef linux
;
# else
timeout(fr_slowtimer, NULL, hz/2);
# endif
# endif /* FreeBSD */
# endif /* OpenBSD */
# endif /* NetBSD */
# endif
done:
RWLOCK_EXIT(&ifs->ifs_ipf_global);
# if (BSD < 199103) || !defined(_KERNEL)
return 0;
# endif
}
#endif /* !SOLARIS && !defined(__hpux) && !defined(__sgi) */
/*ARGSUSED*/
int fr_nextfrag(token, itp, top, tail, lock, ifs)
ipftoken_t *token;
ipfgeniter_t *itp;
ipfr_t **top, ***tail;
ipfrwlock_t *lock;
ipf_stack_t *ifs;
{
ipfr_t *frag, *next, zero;
int error = 0;
READ_ENTER(lock);
/*
* Retrieve "previous" entry from token and find the next entry.
*/
frag = token->ipt_data;
if (frag == NULL)
next = *top;
else
next = frag->ipfr_next;
/*
* If we found an entry, add reference to it and update token.
* Otherwise, zero out data to be returned and NULL out token.
*/
if (next != NULL) {
ATOMIC_INC(next->ipfr_ref);
token->ipt_data = next;
} else {
bzero(&zero, sizeof(zero));
next = &zero;
token->ipt_data = NULL;
}
/*
* Now that we have ref, it's save to give up lock.
*/
RWLOCK_EXIT(lock);
/*
* Copy out data and clean up references and token as needed.
*/
error = COPYOUT(next, itp->igi_data, sizeof(*next));
if (error != 0)
error = EFAULT;
if (token->ipt_data == NULL) {
ipf_freetoken(token, ifs);
} else {
if (frag != NULL)
fr_fragderef(&frag, lock, ifs);
if (next->ipfr_next == NULL)
ipf_freetoken(token, ifs);
}
return error;
}
void fr_fragderef(frp, lock, ifs)
ipfr_t **frp;
ipfrwlock_t *lock;
ipf_stack_t *ifs;
{
ipfr_t *fra;
fra = *frp;
*frp = NULL;
WRITE_ENTER(lock);
fra->ipfr_ref--;
if (fra->ipfr_ref <= 0) {
KFREE(fra);
ifs->ifs_ipfr_stats.ifs_expire++;
ifs->ifs_ipfr_inuse--;
}
RWLOCK_EXIT(lock);
}