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7934237885
freebsd-skq/sys/netinet/ip_fw.c
Ugen J.S. Antsilevich 7934237885 Support all the tcpflag options in firewall. 
Add reading options from file, now ipfw <filename> will
read commands string after string from file , form of strings
same as command line interface.
1995-10-23 03:58:06 +00:00

1037 lines
22 KiB
C
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/*
* Copyright (c) 1993 Daniel Boulet
* Copyright (c) 1994 Ugen J.S.Antsilevich
*
* Redistribution and use in source forms, with and without modification,
* are permitted provided that this entire comment appears intact.
*
* Redistribution in binary form may occur without any restrictions.
* Obviously, it would be nice if you gave credit where credit is due
* but requiring it would be too onerous.
*
* This software is provided ``AS IS'' without any warranties of any kind.
*
* $Id: ip_fw.c,v 1.22 1995/07/31 13:58:35 gpalmer Exp $
*/
/*
* Implement IP packet firewall
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include <netinet/ip_fw.h>
#ifdef IPFIREWALL_DEBUG
#define dprintf1(a) printf(a)
#define dprintf2(a1,a2) printf(a1,a2)
#define dprintf3(a1,a2,a3) printf(a1,a2,a3)
#define dprintf4(a1,a2,a3,a4) printf(a1,a2,a3,a4)
#else
#define dprintf1(a)
#define dprintf2(a1,a2)
#define dprintf3(a1,a2,a3)
#define dprintf4(a1,a2,a3,a4)
#endif
#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif
#define print_ip(a) printf("%ld.%ld.%ld.%ld",(ntohl(a.s_addr)>>24)&0xFF,\
(ntohl(a.s_addr)>>16)&0xFF,\
(ntohl(a.s_addr)>>8)&0xFF,\
(ntohl(a.s_addr))&0xFF);
#ifdef IPFIREWALL_DEBUG
#define dprint_ip(a) print_ip(a)
#else
#define dprint_ip(a)
#endif
/*
* Returns TRUE if the port is matched by the vector, FALSE otherwise
*/
inline int
port_match(portptr, nports, port, range_flag)
u_short *portptr;
int nports;
u_short port;
int range_flag;
{
if (!nports)
return TRUE;
if (range_flag) {
if (portptr[0] <= port && port <= portptr[1]) {
return TRUE;
}
nports -= 2;
portptr += 2;
}
while (nports-- > 0) {
if (*portptr++ == port) {
return TRUE;
}
}
return FALSE;
}
int
tcpflg_match(tcp, f)
struct tcphdr *tcp;
struct ip_fw *f;
{
u_char flg_set, flg_clr;
flg_set = tcp->th_flags & f->fw_tcpf;
flg_clr = tcp->th_flags & f->fw_tcpnf;
if (flg_set != f->fw_tcpf)
return 0;
if (flg_clr != f->fw_tcpnf)
return 0;
return 1;
}
int
ipopts_match(ip, f)
struct ip *ip;
struct ip_fw *f;
{
register u_char *cp;
int opt, optlen, cnt;
u_char opts, nopts, nopts_sve;
cp = (u_char *)(ip + 1);
cnt = (ip->ip_hl << 2) - sizeof (struct ip);
opts = f->fw_ipopt;
nopts = nopts_sve = f->fw_ipnopt;
for (; cnt > 0; cnt -= optlen, cp += optlen) {
opt = cp[IPOPT_OPTVAL];
if (opt == IPOPT_EOL)
break;
if (opt == IPOPT_NOP)
optlen = 1;
else {
optlen = cp[IPOPT_OLEN];
if (optlen <= 0 || optlen > cnt) {
goto bad;
}
}
switch (opt) {
default:
break;
case IPOPT_LSRR:
opts &= ~IP_FW_IPOPT_LSRR;
nopts &= ~IP_FW_IPOPT_LSRR;
break;
case IPOPT_SSRR:
opts &= ~IP_FW_IPOPT_SSRR;
nopts &= ~IP_FW_IPOPT_SSRR;
break;
case IPOPT_RR:
opts &= ~IP_FW_IPOPT_RR;
nopts &= ~IP_FW_IPOPT_RR;
break;
case IPOPT_TS:
opts &= ~IP_FW_IPOPT_TS;
nopts &= ~IP_FW_IPOPT_TS;
break;
}
if (opts == nopts)
break;
}
if (opts == 0 && nopts == nopts_sve)
return 1;
else
return 0;
bad:
if (ip_fw_policy & IP_FW_P_MBIPO)
return 1;
else
return 0;
}
/*
* Returns TRUE if it should be accepted, FALSE otherwise.
*/
#ifdef IPFIREWALL
int
ip_fw_chk(m, ip, rif, chain)
struct mbuf *m;
struct ip *ip;
struct ifnet *rif;
struct ip_fw *chain;
{
register struct ip_fw *f;
struct tcphdr *tcp = (struct tcphdr *) ((u_long *) ip + ip->ip_hl);
struct udphdr *udp = (struct udphdr *) ((u_long *) ip + ip->ip_hl);
struct icmp *icmp = (struct icmp *) ((u_long *) ip + ip->ip_hl);
struct ifaddr *ia = NULL, *ia_p;
struct in_addr src, dst, ia_i;
u_short src_port = 0, dst_port = 0;
u_short f_prt = 0, prt;
/*
* If the chain is empty allow any packet-this is equal to disabling
* firewall.
*/
if (chain == NULL)
return TRUE;
/*
* This way we handle fragmented packets. we ignore all fragments but
* the first one so the whole packet can't be reassembled. This way we
* relay on the full info which stored only in first packet.
*/
if (ip->ip_off & IP_OFFMASK)
return TRUE;
src = ip->ip_src;
dst = ip->ip_dst;
/*
* If we got interface from which packet came-store pointer to it's
* first adress
*/
if (rif != NULL)
ia = rif->if_addrlist;
dprintf1("Packet ");
switch (ip->ip_p) {
case IPPROTO_TCP:
dprintf1("TCP ");
src_port = ntohs(tcp->th_sport);
dst_port = ntohs(tcp->th_dport);
prt = IP_FW_F_TCP;
break;
case IPPROTO_UDP:
dprintf1("UDP ");
src_port = ntohs(udp->uh_sport);
dst_port = ntohs(udp->uh_dport);
prt = IP_FW_F_UDP;
break;
case IPPROTO_ICMP:
dprintf2("ICMP:%u ", icmp->icmp_type);
prt = IP_FW_F_ICMP;
break;
default:
dprintf2("p=%d ", ip->ip_p);
prt = IP_FW_F_ALL;
break;
}
dprint_ip(ip->ip_src);
if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP) {
dprintf2(":%d", src_port);
}
dprintf1(" ");
dprint_ip(ip->ip_dst);
if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP) {
dprintf2(":%d", dst_port);
}
dprintf1("\n");
for (f = chain; f != NULL; f = f->fw_next)
if ((src.s_addr & f->fw_smsk.s_addr) == f->fw_src.s_addr &&
(dst.s_addr & f->fw_dmsk.s_addr) == f->fw_dst.s_addr) {
if (rif == NULL)
goto via_match;
if (f->fw_flg & IP_FW_F_IFNAME) {
/*
* No name/unit set so
* match any.
*/
if (!f->fw_via_name[0])
goto via_match;
if (rif->if_unit == f->fw_via_unit &&
!strncmp(rif->if_name, f->fw_via_name, FW_IFNLEN))
goto via_match;
} else {
/*
* No via ip set so match
* any.
*/
if (!f->fw_via_ip.s_addr)
goto via_match;
for (ia_p = ia; ia_p != NULL; ia_p = ia_p->ifa_next) {
if ((ia_p->ifa_addr == NULL) ||
(ia_p->ifa_addr->sa_family != AF_INET))
continue;
ia_i.s_addr =
((struct sockaddr_in *)(ia_p->ifa_addr))->sin_addr.s_addr;
if (ia_i.s_addr == f->fw_via_ip.s_addr)
goto via_match;
}
}
/*
* If we got here,no "via"'s matched,so we should
* continue to the next firewall entry.
*/
continue;
via_match:
/*
* If we get matching IP options, we may continue
* checking ,else we have nothing to do here.
* We DO check options only if some are set in
* the entry definition. If both set and unset
* options equal - nothing to check.
*/
if (f->fw_ipopt != f->fw_ipnopt)
if (!ipopts_match(ip, f))
continue;
f_prt = f->fw_flg & IP_FW_F_KIND;
if (f_prt == IP_FW_F_ALL) {
/* Universal frwl - we've got a match! */
goto got_match;
} else {
/*
* Specific firewall - packet's protocol must
* match firewall's
*/
if (prt != f_prt)
continue;
if (prt == IP_FW_F_ICMP)
goto got_match;
if (prt == IP_FW_F_TCP)
if (f->fw_tcpf != f->fw_tcpnf)
if (!tcpflg_match(tcp, f))
continue;
if (port_match(&f->fw_pts[0], f->fw_nsp,
src_port, f->fw_flg & IP_FW_F_SRNG) &&
port_match(&f->fw_pts[f->fw_nsp], f->fw_ndp,
dst_port, f->fw_flg & IP_FW_F_DRNG))
goto got_match;
} /* ALL/Specific */
} /* IP addr/mask matches */
/*
* If we get here then none of the firewalls matched. So now we relay
* on policy defined by user-unmatched packet can be ever accepted or
* rejected...
*/
if (ip_fw_policy & IP_FW_P_DENY) {
f = (struct ip_fw *) NULL;
goto bad_packet;
}
return TRUE;
got_match:
#ifdef IPFIREWALL_VERBOSE
/*
* VERY ugly piece of code which actually makes kernel printf for
* denied packets...
*/
if (f->fw_flg & IP_FW_F_PRN) {
if (f->fw_flg & IP_FW_F_ACCEPT)
printf("Accept ");
else
printf("Deny ");
switch (ip->ip_p) {
case IPPROTO_TCP:
printf("TCP ");
break;
case IPPROTO_UDP:
printf("UDP ");
break;
case IPPROTO_ICMP:
printf("ICMP:%u ", icmp->icmp_type);
break;
default:
printf("p=%d ", ip->ip_p);
break;
}
print_ip(ip->ip_src);
if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP)
printf(":%d", src_port);
printf(" ");
print_ip(ip->ip_dst);
if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP)
printf(":%d", dst_port);
printf("\n");
}
#endif
if (f->fw_flg & IP_FW_F_ACCEPT)
return TRUE;
bad_packet:
if (f != NULL) {
/*
* Do not ICMP reply to icmp packets....:) or to packets
* rejected by entry without the special ICMP reply flag.
*/
if ((f_prt == IP_FW_F_ICMP) ||
!(f->fw_flg & IP_FW_F_ICMPRPL)) {
m_freem(m);
return FALSE;
}
if (f_prt == IP_FW_F_ALL)
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0L, 0);
else
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0L, 0);
return FALSE;
}
m_freem(m);
return FALSE;
}
#endif /* IPFIREWALL */
#ifdef IPACCT
void
ip_acct_cnt(ip, rif, chain, nh_conv)
struct ip *ip;
struct ifnet *rif;
struct ip_fw *chain;
int nh_conv;
{
register struct ip_fw *f;
struct tcphdr *tcp = (struct tcphdr *) ((u_long *) ip + ip->ip_hl);
struct udphdr *udp = (struct udphdr *) ((u_long *) ip + ip->ip_hl);
struct ifaddr *ia = NULL, *ia_p;
struct in_addr src, dst, ia_i;
u_short src_port = 0, dst_port = 0;
u_short f_prt, prt = 0;
char rev = 0;
if (chain == NULL)
return;
if (ip->ip_off & IP_OFFMASK)
return;
src = ip->ip_src;
dst = ip->ip_dst;
if (rif != NULL)
ia = rif->if_addrlist;
switch (ip->ip_p) {
case IPPROTO_TCP:
src_port = ntohs(tcp->th_sport);
dst_port = ntohs(tcp->th_dport);
prt = IP_FW_F_TCP;
break;
case IPPROTO_UDP:
src_port = ntohs(udp->uh_sport);
dst_port = ntohs(udp->uh_dport);
prt = IP_FW_F_UDP;
break;
case IPPROTO_ICMP:
prt = IP_FW_F_ICMP;
break;
default:
prt = IP_FW_F_ALL;
break;
}
for (f = chain; f != NULL; f = f->fw_next) {
if ((src.s_addr & f->fw_smsk.s_addr) == f->fw_src.s_addr
&& (dst.s_addr & f->fw_dmsk.s_addr) == f->fw_dst.s_addr) {
rev = 0;
goto addr_match;
}
if ((f->fw_flg & IP_FW_F_BIDIR) &&
((src.s_addr & f->fw_smsk.s_addr) == f->fw_dst.s_addr
&& (dst.s_addr & f->fw_dmsk.s_addr) == f->fw_src.s_addr)) {
rev = 1;
goto addr_match;
}
continue;
addr_match:
/*
* We use here same code for "via" matching as in
* firewall.This is wrong and does not do much use,because in
* most cases instead of interface passed NULL pointer.Need to
* be completely rewritten.
*/
if (rif == NULL)
goto via_match;
if (f->fw_flg & IP_FW_F_IFNAME) {
if (!f->fw_via_name[0])
goto via_match; /* No name/unit set,match any */
if (rif->if_unit == f->fw_via_unit &&
!strncmp(rif->if_name, f->fw_via_name, FW_IFNLEN))
goto via_match;
} else {
/*
* No via ip set so
* match any?
*/
if (!f->fw_via_ip.s_addr)
goto via_match;
for (ia_p = ia; ia_p != NULL; ia_p = ia_p->ifa_next) {
if (!ia_p->ifa_addr || ia_p->ifa_addr->sa_family != AF_INET)
continue;
ia_i.s_addr =
((struct sockaddr_in *) (ia_p->ifa_addr))->sin_addr.s_addr;
if (ia_i.s_addr == f->fw_via_ip.s_addr)
goto via_match;
}
}
/*
* If we got here,no "via"'s matched,so we should continue to
* the next firewall entry.
*/
continue;
via_match:
f_prt = f->fw_flg & IP_FW_F_KIND;
if (f_prt == IP_FW_F_ALL) {
/* Universal frwl - we've got a match! */
f->fw_pcnt++; /* Rise packet count */
/*
* Rise byte count, if need to convert from host to
* network byte order,do it.
*/
if (nh_conv)
f->fw_bcnt += ntohs(ip->ip_len);
else
f->fw_bcnt += ip->ip_len;
} else {
/*
* Specific firewall - packet's protocol must match
* firewall's
*/
if (prt == f_prt) {
if ((prt == IP_FW_F_ICMP ||
(port_match(&f->fw_pts[0], f->fw_nsp, src_port,
f->fw_flg & IP_FW_F_SRNG) &&
port_match(&f->fw_pts[f->fw_nsp], f->fw_ndp, dst_port,
f->fw_flg & IP_FW_F_DRNG))) ||
((rev) && (port_match(&f->fw_pts[0], f->fw_nsp, dst_port,
f->fw_flg & IP_FW_F_SRNG) &&
port_match(&f->fw_pts[f->fw_nsp], f->fw_ndp, src_port,
f->fw_flg & IP_FW_F_DRNG)))) {
f->fw_pcnt++; /* Rise packet count */
/*
* Rise byte count, if need to convert
* from host to network byte order,do
* it.
*/
if (nh_conv)
f->fw_bcnt += ntohs(ip->ip_len);
else
f->fw_bcnt += ip->ip_len;
} /* Ports match */
} /* Proto matches */
} /* ALL/Specific */
} /* IP addr/mask matches */
}
#endif /* IPACCT */
static void
zero_fw_chain(chainptr)
struct ip_fw *chainptr;
{
struct ip_fw *ctmp = chainptr;
while (ctmp != NULL) {
ctmp->fw_pcnt = 0l;
ctmp->fw_bcnt = 0l;
ctmp = ctmp->fw_next;
}
}
static void
free_fw_chain(chainptr)
struct ip_fw **chainptr;
{
int s;
s = splnet();
while (*chainptr != NULL) {
struct ip_fw *ftmp;
ftmp = *chainptr;
*chainptr = ftmp->fw_next;
free(ftmp, M_IPFW);
}
splx(s);
}
static int
add_entry(chainptr, frwl)
struct ip_fw **chainptr;
struct ip_fw *frwl;
{
struct ip_fw *ftmp;
struct ip_fw *chtmp = NULL;
struct ip_fw *chtmp_prev = NULL;
u_long m_src_mask, m_dst_mask;
u_long n_sa, n_da, o_sa, o_da, o_sm, o_dm, n_sm, n_dm;
u_short n_sr, n_dr, o_sr, o_dr;
u_short oldkind, newkind;
int addb4 = 0;
int n_o, n_n;
int s;
s = splnet();
ftmp = malloc(sizeof(struct ip_fw), M_IPFW, M_DONTWAIT);
if (ftmp == NULL) {
dprintf1("ip_fw_ctl: malloc said no\n");
splx(s);
return (ENOSPC);
}
bcopy(frwl, ftmp, sizeof(struct ip_fw));
ftmp->fw_pcnt = 0L;
ftmp->fw_bcnt = 0L;
ftmp->fw_next = NULL;
if (*chainptr == NULL) {
*chainptr = ftmp;
} else {
chtmp_prev = NULL;
for (chtmp = *chainptr; chtmp != NULL; chtmp = chtmp->fw_next) {
addb4 = 0;
newkind = ftmp->fw_flg & IP_FW_F_KIND;
oldkind = chtmp->fw_flg & IP_FW_F_KIND;
if (newkind != IP_FW_F_ALL &&
oldkind != IP_FW_F_ALL &&
oldkind != newkind) {
chtmp_prev = chtmp;
continue;
}
/*
* Very very *UGLY* code... Sorry,but i had to do
* this....
*/
n_sa = ntohl(ftmp->fw_src.s_addr);
n_da = ntohl(ftmp->fw_dst.s_addr);
n_sm = ntohl(ftmp->fw_smsk.s_addr);
n_dm = ntohl(ftmp->fw_dmsk.s_addr);
o_sa = ntohl(chtmp->fw_src.s_addr);
o_da = ntohl(chtmp->fw_dst.s_addr);
o_sm = ntohl(chtmp->fw_smsk.s_addr);
o_dm = ntohl(chtmp->fw_dmsk.s_addr);
m_src_mask = o_sm & n_sm;
m_dst_mask = o_dm & n_dm;
if ((o_sa & m_src_mask) == (n_sa & m_src_mask)) {
if (n_sm > o_sm)
addb4++;
if (n_sm < o_sm)
addb4--;
}
if ((o_da & m_dst_mask) == (n_da & m_dst_mask)) {
if (n_dm > o_dm)
addb4++;
if (n_dm < o_dm)
addb4--;
}
if (((o_da & o_dm) == (n_da & n_dm))
&& ((o_sa & o_sm) == (n_sa & n_sm))) {
if (newkind != IP_FW_F_ALL &&
oldkind == IP_FW_F_ALL)
addb4++;
if (newkind == oldkind && (oldkind == IP_FW_F_TCP ||
oldkind == IP_FW_F_UDP)) {
/*
* Here the main idea is to check the
* size of port range which the frwl
* covers We actually don't check
* their values but just the wideness
* of range they have so that less
* wide ranges or single ports go
* first and wide ranges go later. No
* ports at all treated as a range of
* maximum number of ports.
*/
if (ftmp->fw_flg & IP_FW_F_SRNG)
n_sr = ftmp->fw_pts[1] - ftmp->fw_pts[0];
else
n_sr = (ftmp->fw_nsp) ?
ftmp->fw_nsp : USHRT_MAX;
if (chtmp->fw_flg & IP_FW_F_SRNG)
o_sr = chtmp->fw_pts[1] - chtmp->fw_pts[0];
else
o_sr = (chtmp->fw_nsp) ?
chtmp->fw_nsp : USHRT_MAX;
if (n_sr < o_sr)
addb4++;
if (n_sr > o_sr)
addb4--;
n_n = ftmp->fw_nsp;
n_o = chtmp->fw_nsp;
/*
* Actually this cannot happen as the
* frwl control procedure checks for
* number of ports in source and
* destination range but we will try
* to be more safe.
*/
if ((n_n > (IP_FW_MAX_PORTS - 2)) ||
(n_o > (IP_FW_MAX_PORTS - 2)))
goto skip_check;
if (ftmp->fw_flg & IP_FW_F_DRNG)
n_dr = ftmp->fw_pts[n_n + 1] - ftmp->fw_pts[n_n];
else
n_dr = (ftmp->fw_ndp) ?
ftmp->fw_ndp : USHRT_MAX;
if (chtmp->fw_flg & IP_FW_F_DRNG)
o_dr = chtmp->fw_pts[n_o + 1] - chtmp->fw_pts[n_o];
else
o_dr = (chtmp->fw_ndp) ?
chtmp->fw_ndp : USHRT_MAX;
if (n_dr < o_dr)
addb4++;
if (n_dr > o_dr)
addb4--;
if (n_dr == o_dr && n_sr == o_sr &&
oldkind == IP_FW_F_TCP) {
if (ftmp->fw_tcpf != 0 &&
chtmp->fw_tcpf == 0)
addb4++;
if (ftmp->fw_tcpnf != 0 &&
chtmp->fw_tcpnf == 0)
addb4++;
}
skip_check:
}
if (ftmp->fw_ipopt != 0 && chtmp->fw_ipopt == 0)
addb4++;
if (ftmp->fw_ipnopt != 0 && chtmp->fw_ipnopt == 0)
addb4++;
}
if (addb4 > 0) {
if (chtmp_prev != NULL) {
chtmp_prev->fw_next = ftmp;
ftmp->fw_next = chtmp;
} else {
*chainptr = ftmp;
ftmp->fw_next = chtmp;
}
splx(s);
return 0;
}
chtmp_prev = chtmp;
}
if (chtmp_prev != NULL)
chtmp_prev->fw_next = ftmp;
else
#ifdef DIAGNOSTIC
panic("Can't happen");
#else
*chainptr = ftmp;
#endif
}
splx(s);
return (0);
}
static int
del_entry(chainptr, frwl)
struct ip_fw **chainptr;
struct ip_fw *frwl;
{
struct ip_fw *ftmp, *ltmp;
u_short tport1, tport2, tmpnum;
char matches, was_found;
int s;
s = splnet();
ftmp = *chainptr;
if (ftmp == NULL) {
dprintf1("ip_fw_ctl: chain is empty\n");
splx(s);
return (EINVAL);
}
ltmp = NULL;
was_found = 0;
while (ftmp != NULL) {
matches = 1;
if (ftmp->fw_src.s_addr != frwl->fw_src.s_addr ||
ftmp->fw_dst.s_addr != frwl->fw_dst.s_addr ||
ftmp->fw_smsk.s_addr != frwl->fw_smsk.s_addr ||
ftmp->fw_dmsk.s_addr != frwl->fw_dmsk.s_addr ||
ftmp->fw_via_ip.s_addr != frwl->fw_via_ip.s_addr ||
ftmp->fw_flg != frwl->fw_flg)
matches = 0;
tport1 = ftmp->fw_nsp + ftmp->fw_ndp;
tport2 = frwl->fw_nsp + frwl->fw_ndp;
if (tport1 != tport2)
matches = 0;
else if (tport1 != 0) {
for (tmpnum = 0; tmpnum < tport1 && tmpnum < IP_FW_MAX_PORTS; tmpnum++)
if (ftmp->fw_pts[tmpnum] != frwl->fw_pts[tmpnum])
matches = 0;
}
if (matches) {
was_found = 1;
if (ltmp != NULL) {
ltmp->fw_next = ftmp->fw_next;
free(ftmp, M_IPFW);
ftmp = ltmp->fw_next;
} else {
*chainptr = ftmp->fw_next;
free(ftmp, M_IPFW);
ftmp = *chainptr;
}
} else {
ltmp = ftmp;
ftmp = ftmp->fw_next;
}
}
splx(s);
if (was_found)
return 0;
else
return (EINVAL);
}
static int
clr_entry(chainptr, frwl)
struct ip_fw **chainptr;
struct ip_fw *frwl;
{
struct ip_fw *ftmp, *ltmp;
u_short tport1, tport2, tmpnum;
char matches, was_found;
ftmp = *chainptr;
if (ftmp == NULL) {
dprintf1("ip_fw_ctl: chain is empty\n");
return (EINVAL);
}
was_found = 0;
while (ftmp != NULL) {
matches = 1;
if (ftmp->fw_src.s_addr != frwl->fw_src.s_addr ||
ftmp->fw_dst.s_addr != frwl->fw_dst.s_addr ||
ftmp->fw_smsk.s_addr != frwl->fw_smsk.s_addr ||
ftmp->fw_dmsk.s_addr != frwl->fw_dmsk.s_addr ||
ftmp->fw_via_ip.s_addr != frwl->fw_via_ip.s_addr ||
ftmp->fw_flg != frwl->fw_flg)
matches = 0;
tport1 = ftmp->fw_nsp + ftmp->fw_ndp;
tport2 = frwl->fw_nsp + frwl->fw_ndp;
if (tport1 != tport2)
matches = 0;
else if (tport1 != 0) {
for (tmpnum = 0; tmpnum < tport1 && tmpnum < IP_FW_MAX_PORTS; tmpnum++)
if (ftmp->fw_pts[tmpnum] != frwl->fw_pts[tmpnum])
matches = 0;
}
if (matches) {
was_found = 1;
ftmp->fw_pcnt = 0L;
ftmp->fw_bcnt = 0L;
}
ftmp = ftmp->fw_next;
}
if (was_found)
return 0;
else
return (EINVAL);
}
struct ip_fw *
check_ipfw_struct(m)
struct mbuf *m;
{
struct ip_fw *frwl;
if (m->m_len != sizeof(struct ip_fw)) {
dprintf3("ip_fw_ctl: len=%d, want %d\n", m->m_len,
sizeof(struct ip_fw));
return (NULL);
}
frwl = mtod(m, struct ip_fw *);
if ((frwl->fw_flg & ~IP_FW_F_MASK) != 0) {
dprintf2("ip_fw_ctl: undefined flag bits set (flags=%x)\n",
frwl->fw_flg);
return (NULL);
}
if ((frwl->fw_flg & IP_FW_F_SRNG) && frwl->fw_nsp < 2) {
dprintf2("ip_fw_ctl: src range set but n_src_p=%d\n",
frwl->fw_nsp);
return (NULL);
}
if ((frwl->fw_flg & IP_FW_F_DRNG) && frwl->fw_ndp < 2) {
dprintf2("ip_fw_ctl: dst range set but n_dst_p=%d\n",
frwl->fw_ndp);
return (NULL);
}
if (frwl->fw_nsp + frwl->fw_ndp > IP_FW_MAX_PORTS) {
dprintf3("ip_fw_ctl: too many ports (%d+%d)\n",
frwl->fw_nsp, frwl->fw_ndp);
return (NULL);
}
#if 0
if ((frwl->fw_flg & IP_FW_F_KIND) == IP_FW_F_ICMP) {
dprintf1("ip_fw_ctl: request for unsupported ICMP frwling\n");
return (NULL);
}
#endif
return frwl;
}
#ifdef IPACCT
int
ip_acct_ctl(stage, m)
int stage;
struct mbuf *m;
{
if (stage == IP_ACCT_FLUSH) {
free_fw_chain(&ip_acct_chain);
return (0);
}
if (stage == IP_ACCT_ZERO) {
zero_fw_chain(ip_acct_chain);
return (0);
}
if (stage == IP_ACCT_ADD ||
stage == IP_ACCT_DEL ||
stage == IP_ACCT_CLR) {
struct ip_fw *frwl;
if ((frwl = check_ipfw_struct(m)) == NULL)
return (EINVAL);
switch (stage) {
case IP_ACCT_ADD:
return (add_entry(&ip_acct_chain, frwl));
case IP_ACCT_DEL:
return (del_entry(&ip_acct_chain, frwl));
case IP_ACCT_CLR:
return (clr_entry(&ip_acct_chain, frwl));
default:
#ifdef DIAGNOSTIC
panic("Can't happen");
#else
dprintf2("ip_acct_ctl: unknown request %d\n", stage);
return (EINVAL);
#endif
}
}
dprintf2("ip_acct_ctl: unknown request %d\n", stage);
return (EINVAL);
}
#endif
#ifdef IPFIREWALL
int
ip_fw_ctl(stage, m)
int stage;
struct mbuf *m;
{
if (stage == IP_FW_FLUSH) {
free_fw_chain(&ip_fw_chain);
return (0);
}
if (m == NULL) {
printf("ip_fw_ctl: NULL mbuf ptr\n");
return (EINVAL);
}
if (stage == IP_FW_POLICY) {
u_short *tmp_policy_ptr;
tmp_policy_ptr = mtod(m, u_short *);
if ((*tmp_policy_ptr) & ~IP_FW_P_MASK)
return (EINVAL);
ip_fw_policy = *tmp_policy_ptr;
return 0;
}
/*
* Here we really working hard-adding new elements
* to firewall chain or deleting'em
*/
if (stage == IP_FW_ADD ||
stage == IP_FW_DEL) {
struct ip_fw *frwl;
if ((frwl = check_ipfw_struct(m)) == NULL)
return (EINVAL);
switch (stage) {
case IP_FW_ADD:
return (add_entry(&ip_fw_chain, frwl));
case IP_FW_DEL:
return (del_entry(&ip_fw_chain, frwl));
default:
#ifdef DIAGNOSTIC
panic("Can't happen");
#else
dprintf2("ip_fw_ctl: unknown request %d\n", stage);
return (EINVAL);
#endif
}
}
dprintf2("ip_fw_ctl: unknown request %d\n", stage);
return (EINVAL);
}
#endif /* IPFIREWALL */
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