859 lines
26 KiB
C
859 lines
26 KiB
C
/* $NetBSD$ */
|
|
|
|
/*
|
|
* Copyright (C) 1993-2003 by Darren Reed.
|
|
*
|
|
* 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>
|
|
#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)
|
|
# 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/ip_proxy.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 2004/01/27 00:24:54 darrenr Exp";
|
|
#endif
|
|
|
|
|
|
static ipfr_t *ipfr_list = NULL;
|
|
static ipfr_t **ipfr_tail = &ipfr_list;
|
|
static ipfr_t **ipfr_heads;
|
|
|
|
static ipfr_t *ipfr_natlist = NULL;
|
|
static ipfr_t **ipfr_nattail = &ipfr_natlist;
|
|
static ipfr_t **ipfr_nattab;
|
|
|
|
static ipfr_t *ipfr_ipidlist = NULL;
|
|
static ipfr_t **ipfr_ipidtail = &ipfr_ipidlist;
|
|
static ipfr_t **ipfr_ipidtab;
|
|
|
|
static ipfrstat_t ipfr_stats;
|
|
static int ipfr_inuse = 0;
|
|
int ipfr_size = IPFT_SIZE;
|
|
|
|
int fr_ipfrttl = 120; /* 60 seconds */
|
|
int fr_frag_lock = 0;
|
|
int fr_frag_init = 0;
|
|
u_long fr_ticks = 0;
|
|
|
|
|
|
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 ***));
|
|
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
/* Function: fr_fraginit */
|
|
/* Returns: int - 0 == success, -1 == error */
|
|
/* Parameters: Nil */
|
|
/* */
|
|
/* Initialise the hash tables for the fragment cache lookups. */
|
|
/* ------------------------------------------------------------------------ */
|
|
int fr_fraginit()
|
|
{
|
|
KMALLOCS(ipfr_heads, ipfr_t **, ipfr_size * sizeof(ipfr_t *));
|
|
if (ipfr_heads == NULL)
|
|
return -1;
|
|
bzero((char *)ipfr_heads, ipfr_size * sizeof(ipfr_t *));
|
|
|
|
KMALLOCS(ipfr_nattab, ipfr_t **, ipfr_size * sizeof(ipfr_t *));
|
|
if (ipfr_nattab == NULL)
|
|
return -1;
|
|
bzero((char *)ipfr_nattab, ipfr_size * sizeof(ipfr_t *));
|
|
|
|
KMALLOCS(ipfr_ipidtab, ipfr_t **, ipfr_size * sizeof(ipfr_t *));
|
|
if (ipfr_ipidtab == NULL)
|
|
return -1;
|
|
bzero((char *)ipfr_ipidtab, ipfr_size * sizeof(ipfr_t *));
|
|
|
|
RWLOCK_INIT(&ipf_frag, "ipf fragment rwlock");
|
|
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()
|
|
{
|
|
if (fr_frag_init == 1) {
|
|
fr_fragclear();
|
|
|
|
RW_DESTROY(&ipf_frag);
|
|
fr_frag_init = 0;
|
|
}
|
|
|
|
if (ipfr_heads != NULL)
|
|
KFREES(ipfr_heads, ipfr_size * sizeof(ipfr_t *));
|
|
ipfr_heads = NULL;
|
|
|
|
if (ipfr_nattab != NULL)
|
|
KFREES(ipfr_nattab, ipfr_size * sizeof(ipfr_t *));
|
|
ipfr_nattab = NULL;
|
|
|
|
if (ipfr_ipidtab != NULL)
|
|
KFREES(ipfr_ipidtab, ipfr_size * sizeof(ipfr_t *));
|
|
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()
|
|
{
|
|
ipfr_stats.ifs_table = ipfr_heads;
|
|
ipfr_stats.ifs_nattab = ipfr_nattab;
|
|
ipfr_stats.ifs_inuse = ipfr_inuse;
|
|
return &ipfr_stats;
|
|
}
|
|
|
|
|
|
/* ------------------------------------------------------------------------ */
|
|
/* 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;
|
|
ip_t *ip;
|
|
|
|
if (ipfr_inuse >= IPFT_SIZE)
|
|
return NULL;
|
|
|
|
if ((fin->fin_flx & (FI_FRAG|FI_BAD)) != FI_FRAG)
|
|
return NULL;
|
|
|
|
ip = fin->fin_ip;
|
|
|
|
if (pass & FR_FRSTRICT)
|
|
if ((ip->ip_off & IP_OFFMASK) != 0)
|
|
return NULL;
|
|
|
|
frag.ipfr_p = ip->ip_p;
|
|
idx = ip->ip_p;
|
|
frag.ipfr_id = ip->ip_id;
|
|
idx += ip->ip_id;
|
|
frag.ipfr_tos = ip->ip_tos;
|
|
frag.ipfr_src.s_addr = ip->ip_src.s_addr;
|
|
idx += ip->ip_src.s_addr;
|
|
frag.ipfr_dst.s_addr = ip->ip_dst.s_addr;
|
|
idx += ip->ip_dst.s_addr;
|
|
frag.ipfr_ifp = fin->fin_ifp;
|
|
idx *= 127;
|
|
idx %= IPFT_SIZE;
|
|
|
|
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;
|
|
|
|
/*
|
|
* 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)) {
|
|
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) {
|
|
ipfr_stats.ifs_nomem++;
|
|
return NULL;
|
|
}
|
|
|
|
if ((fra->ipfr_rule = fin->fin_fr) != NULL)
|
|
fin->fin_fr->fr_ref++;
|
|
|
|
/*
|
|
* 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 = fr_ticks + fr_ipfrttl;
|
|
|
|
/*
|
|
* Compute the offset of the expected start of the next packet.
|
|
*/
|
|
off = ip->ip_off & IP_OFFMASK;
|
|
if (off == 0)
|
|
fra->ipfr_seen0 = 1;
|
|
fra->ipfr_off = off + (fin->fin_dlen >> 3);
|
|
fra->ipfr_pass = pass;
|
|
ipfr_stats.ifs_new++;
|
|
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;
|
|
|
|
if ((fin->fin_v != 4) || (fr_frag_lock != 0))
|
|
return -1;
|
|
|
|
WRITE_ENTER(&ipf_frag);
|
|
fra = ipfr_newfrag(fin, pass, ipfr_heads);
|
|
if (fra != NULL) {
|
|
*ipfr_tail = fra;
|
|
fra->ipfr_prev = ipfr_tail;
|
|
ipfr_tail = &fra->ipfr_next;
|
|
if (ipfr_list == NULL)
|
|
ipfr_list = fra;
|
|
fra->ipfr_next = NULL;
|
|
}
|
|
RWLOCK_EXIT(&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;
|
|
|
|
if ((fin->fin_v != 4) || (fr_frag_lock != 0))
|
|
return 0;
|
|
|
|
WRITE_ENTER(&ipf_natfrag);
|
|
fra = ipfr_newfrag(fin, pass, ipfr_nattab);
|
|
if (fra != NULL) {
|
|
fra->ipfr_data = nat;
|
|
nat->nat_data = fra;
|
|
*ipfr_nattail = fra;
|
|
fra->ipfr_prev = ipfr_nattail;
|
|
ipfr_nattail = &fra->ipfr_next;
|
|
fra->ipfr_next = NULL;
|
|
}
|
|
RWLOCK_EXIT(&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;
|
|
|
|
if ((fin->fin_v != 4) || (fr_frag_lock))
|
|
return 0;
|
|
|
|
WRITE_ENTER(&ipf_ipidfrag);
|
|
fra = ipfr_newfrag(fin, 0, ipfr_ipidtab);
|
|
if (fra != NULL) {
|
|
fra->ipfr_data = (void *)ipid;
|
|
*ipfr_ipidtail = fra;
|
|
fra->ipfr_prev = ipfr_ipidtail;
|
|
ipfr_ipidtail = &fra->ipfr_next;
|
|
fra->ipfr_next = NULL;
|
|
}
|
|
RWLOCK_EXIT(&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;
|
|
ip_t *ip;
|
|
|
|
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.
|
|
*/
|
|
ip = fin->fin_ip;
|
|
frag.ipfr_p = ip->ip_p;
|
|
idx = ip->ip_p;
|
|
frag.ipfr_id = ip->ip_id;
|
|
idx += ip->ip_id;
|
|
frag.ipfr_tos = ip->ip_tos;
|
|
frag.ipfr_src.s_addr = ip->ip_src.s_addr;
|
|
idx += ip->ip_src.s_addr;
|
|
frag.ipfr_dst.s_addr = ip->ip_dst.s_addr;
|
|
idx += ip->ip_dst.s_addr;
|
|
frag.ipfr_ifp = fin->fin_ifp;
|
|
idx *= 127;
|
|
idx %= IPFT_SIZE;
|
|
|
|
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;
|
|
|
|
/*
|
|
* 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(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 = ip->ip_off & IP_OFFMASK;
|
|
if (f->ipfr_seen0) {
|
|
if (off == 0) {
|
|
ATOMIC_INCL(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 (!(ip->ip_off & IP_MF))
|
|
f->ipfr_ttl = fr_ticks + 1;
|
|
f->ipfr_off = (fin->fin_dlen >> 3) + off;
|
|
} else if (f->ipfr_pass & FR_FRSTRICT)
|
|
continue;
|
|
ATOMIC_INCL(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;
|
|
|
|
if ((fin->fin_v != 4) || (fr_frag_lock) || !ipfr_natlist)
|
|
return NULL;
|
|
READ_ENTER(&ipf_natfrag);
|
|
ipf = fr_fraglookup(fin, ipfr_nattab);
|
|
if (ipf != NULL) {
|
|
nat = ipf->ipfr_data;
|
|
/*
|
|
* This is the last fragment for this packet.
|
|
*/
|
|
if ((ipf->ipfr_ttl == fr_ticks + 1) && (nat != NULL)) {
|
|
nat->nat_data = NULL;
|
|
ipf->ipfr_data = NULL;
|
|
}
|
|
} else
|
|
nat = NULL;
|
|
RWLOCK_EXIT(&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;
|
|
|
|
if ((fin->fin_v != 4) || (fr_frag_lock) || !ipfr_ipidlist)
|
|
return 0xffffffff;
|
|
|
|
READ_ENTER(&ipf_ipidfrag);
|
|
ipf = fr_fraglookup(fin, ipfr_ipidtab);
|
|
if (ipf != NULL)
|
|
id = (u_32_t)ipf->ipfr_data;
|
|
else
|
|
id = 0xffffffff;
|
|
RWLOCK_EXIT(&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;
|
|
|
|
if ((fin->fin_v != 4) || (fr_frag_lock) || (ipfr_list == NULL))
|
|
return NULL;
|
|
|
|
READ_ENTER(&ipf_frag);
|
|
fra = fr_fraglookup(fin, 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;
|
|
}
|
|
}
|
|
RWLOCK_EXIT(&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)
|
|
void *ptr;
|
|
{
|
|
ipfr_t *fr;
|
|
|
|
WRITE_ENTER(&ipf_frag);
|
|
for (fr = ipfr_list; fr; fr = fr->ipfr_next)
|
|
if (fr->ipfr_data == ptr)
|
|
fr->ipfr_data = NULL;
|
|
RWLOCK_EXIT(&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)
|
|
void *ptr;
|
|
{
|
|
ipfr_t *fr;
|
|
|
|
WRITE_ENTER(&ipf_natfrag);
|
|
for (fr = ipfr_natlist; fr; fr = fr->ipfr_next)
|
|
if (fr->ipfr_data == ptr)
|
|
fr->ipfr_data = NULL;
|
|
RWLOCK_EXIT(&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)
|
|
ipfr_t *fra, ***tail;
|
|
{
|
|
frentry_t *fr;
|
|
|
|
fr = fra->ipfr_rule;
|
|
if (fr != NULL)
|
|
(void)fr_derefrule(&fr);
|
|
|
|
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;
|
|
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()
|
|
{
|
|
ipfr_t *fra;
|
|
nat_t *nat;
|
|
|
|
WRITE_ENTER(&ipf_frag);
|
|
while ((fra = ipfr_list) != NULL)
|
|
fr_fragdelete(fra, &ipfr_tail);
|
|
ipfr_tail = &ipfr_list;
|
|
RWLOCK_EXIT(&ipf_frag);
|
|
|
|
WRITE_ENTER(&ipf_nat);
|
|
WRITE_ENTER(&ipf_natfrag);
|
|
while ((fra = ipfr_natlist) != NULL) {
|
|
nat = fra->ipfr_data;
|
|
if (nat != NULL) {
|
|
if (nat->nat_data == fra)
|
|
nat->nat_data = NULL;
|
|
}
|
|
fr_fragdelete(fra, &ipfr_nattail);
|
|
}
|
|
ipfr_nattail = &ipfr_natlist;
|
|
RWLOCK_EXIT(&ipf_natfrag);
|
|
RWLOCK_EXIT(&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()
|
|
{
|
|
ipfr_t **fp, *fra;
|
|
nat_t *nat;
|
|
#if defined(USE_SPL) && defined(_KERNEL)
|
|
int s;
|
|
#endif
|
|
|
|
if (fr_frag_lock)
|
|
return;
|
|
|
|
SPL_NET(s);
|
|
WRITE_ENTER(&ipf_frag);
|
|
/*
|
|
* Go through the entire table, looking for entries to expire,
|
|
* which is indicated by the ttl being less than or equal to fr_ticks.
|
|
*/
|
|
for (fp = &ipfr_list; ((fra = *fp) != NULL); ) {
|
|
if (fra->ipfr_ttl > fr_ticks)
|
|
break;
|
|
fr_fragdelete(fra, &ipfr_tail);
|
|
ipfr_stats.ifs_expire++;
|
|
ipfr_inuse--;
|
|
}
|
|
RWLOCK_EXIT(&ipf_frag);
|
|
|
|
WRITE_ENTER(&ipf_ipidfrag);
|
|
for (fp = &ipfr_ipidlist; ((fra = *fp) != NULL); ) {
|
|
if (fra->ipfr_ttl > fr_ticks)
|
|
break;
|
|
fr_fragdelete(fra, &ipfr_ipidtail);
|
|
ipfr_stats.ifs_expire++;
|
|
ipfr_inuse--;
|
|
}
|
|
RWLOCK_EXIT(&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(&ipf_nat);
|
|
WRITE_ENTER(&ipf_natfrag);
|
|
for (fp = &ipfr_natlist; ((fra = *fp) != NULL); ) {
|
|
if (fra->ipfr_ttl > fr_ticks)
|
|
break;
|
|
nat = fra->ipfr_data;
|
|
if (nat != NULL) {
|
|
if (nat->nat_data == fra)
|
|
nat->nat_data = NULL;
|
|
}
|
|
fr_fragdelete(fra, &ipfr_nattail);
|
|
ipfr_stats.ifs_expire++;
|
|
ipfr_inuse--;
|
|
}
|
|
RWLOCK_EXIT(&ipf_natfrag);
|
|
RWLOCK_EXIT(&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__))
|
|
# if defined(_KERNEL) && ((BSD >= 199103) || defined(__sgi))
|
|
void fr_slowtimer __P((void *ptr))
|
|
# else
|
|
int fr_slowtimer()
|
|
# endif
|
|
{
|
|
READ_ENTER(&ipf_global);
|
|
|
|
fr_fragexpire();
|
|
fr_timeoutstate();
|
|
fr_natexpire();
|
|
fr_authexpire();
|
|
fr_ticks++;
|
|
if (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(&ipf_global);
|
|
# if (BSD < 199103) || !defined(_KERNEL)
|
|
return 0;
|
|
# endif
|
|
}
|
|
#endif /* !SOLARIS && !defined(__hpux) && !defined(__sgi) */
|