https://bugs.freebsd.org/269753 PR: 269753 Reported by: Igor Ostapenko Approved by: doc, src (delphij, imp, zlei) Differential revision: https://reviews.freebsd.org/D38741
3704 lines
94 KiB
C
3704 lines
94 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
|
|
*
|
|
* Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
/*
|
|
* The FreeBSD IP packet firewall, main file
|
|
*/
|
|
|
|
#include "opt_ipfw.h"
|
|
#include "opt_ipdivert.h"
|
|
#include "opt_inet.h"
|
|
#ifndef INET
|
|
#error "IPFIREWALL requires INET"
|
|
#endif /* INET */
|
|
#include "opt_inet6.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/condvar.h>
|
|
#include <sys/counter.h>
|
|
#include <sys/eventhandler.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/mbuf.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/jail.h>
|
|
#include <sys/module.h>
|
|
#include <sys/priv.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/rwlock.h>
|
|
#include <sys/rmlock.h>
|
|
#include <sys/sdt.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/socketvar.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/syslog.h>
|
|
#include <sys/ucred.h>
|
|
#include <net/ethernet.h> /* for ETHERTYPE_IP */
|
|
#include <net/if.h>
|
|
#include <net/if_var.h>
|
|
#include <net/if_private.h>
|
|
#include <net/route.h>
|
|
#include <net/route/nhop.h>
|
|
#include <net/pfil.h>
|
|
#include <net/vnet.h>
|
|
|
|
#include <netpfil/pf/pf_mtag.h>
|
|
|
|
#include <netinet/in.h>
|
|
#include <netinet/in_var.h>
|
|
#include <netinet/in_pcb.h>
|
|
#include <netinet/ip.h>
|
|
#include <netinet/ip_var.h>
|
|
#include <netinet/ip_icmp.h>
|
|
#include <netinet/ip_fw.h>
|
|
#include <netinet/ip_carp.h>
|
|
#include <netinet/pim.h>
|
|
#include <netinet/tcp_var.h>
|
|
#include <netinet/udp.h>
|
|
#include <netinet/udp_var.h>
|
|
#include <netinet/sctp.h>
|
|
#include <netinet/sctp_crc32.h>
|
|
#include <netinet/sctp_header.h>
|
|
|
|
#include <netinet/ip6.h>
|
|
#include <netinet/icmp6.h>
|
|
#include <netinet/in_fib.h>
|
|
#ifdef INET6
|
|
#include <netinet6/in6_fib.h>
|
|
#include <netinet6/in6_pcb.h>
|
|
#include <netinet6/scope6_var.h>
|
|
#include <netinet6/ip6_var.h>
|
|
#endif
|
|
|
|
#include <net/if_gre.h> /* for struct grehdr */
|
|
|
|
#include <netpfil/ipfw/ip_fw_private.h>
|
|
|
|
#include <machine/in_cksum.h> /* XXX for in_cksum */
|
|
|
|
#ifdef MAC
|
|
#include <security/mac/mac_framework.h>
|
|
#endif
|
|
|
|
#define IPFW_PROBE(probe, arg0, arg1, arg2, arg3, arg4, arg5) \
|
|
SDT_PROBE6(ipfw, , , probe, arg0, arg1, arg2, arg3, arg4, arg5)
|
|
|
|
SDT_PROVIDER_DEFINE(ipfw);
|
|
SDT_PROBE_DEFINE6(ipfw, , , rule__matched,
|
|
"int", /* retval */
|
|
"int", /* af */
|
|
"void *", /* src addr */
|
|
"void *", /* dst addr */
|
|
"struct ip_fw_args *", /* args */
|
|
"struct ip_fw *" /* rule */);
|
|
|
|
/*
|
|
* static variables followed by global ones.
|
|
* All ipfw global variables are here.
|
|
*/
|
|
|
|
VNET_DEFINE_STATIC(int, fw_deny_unknown_exthdrs);
|
|
#define V_fw_deny_unknown_exthdrs VNET(fw_deny_unknown_exthdrs)
|
|
|
|
VNET_DEFINE_STATIC(int, fw_permit_single_frag6) = 1;
|
|
#define V_fw_permit_single_frag6 VNET(fw_permit_single_frag6)
|
|
|
|
#ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
|
|
static int default_to_accept = 1;
|
|
#else
|
|
static int default_to_accept;
|
|
#endif
|
|
|
|
VNET_DEFINE(int, autoinc_step);
|
|
VNET_DEFINE(int, fw_one_pass) = 1;
|
|
|
|
VNET_DEFINE(unsigned int, fw_tables_max);
|
|
VNET_DEFINE(unsigned int, fw_tables_sets) = 0; /* Don't use set-aware tables */
|
|
/* Use 128 tables by default */
|
|
static unsigned int default_fw_tables = IPFW_TABLES_DEFAULT;
|
|
|
|
static int jump_lookup_pos(struct ip_fw_chain *chain, struct ip_fw *f, int num,
|
|
int tablearg, int jump_backwards);
|
|
#ifndef LINEAR_SKIPTO
|
|
static int jump_cached(struct ip_fw_chain *chain, struct ip_fw *f, int num,
|
|
int tablearg, int jump_backwards);
|
|
#define JUMP(ch, f, num, targ, back) jump_cached(ch, f, num, targ, back)
|
|
#else
|
|
#define JUMP(ch, f, num, targ, back) jump_lookup_pos(ch, f, num, targ, back)
|
|
#endif
|
|
|
|
/*
|
|
* Each rule belongs to one of 32 different sets (0..31).
|
|
* The variable set_disable contains one bit per set.
|
|
* If the bit is set, all rules in the corresponding set
|
|
* are disabled. Set RESVD_SET(31) is reserved for the default rule
|
|
* and rules that are not deleted by the flush command,
|
|
* and CANNOT be disabled.
|
|
* Rules in set RESVD_SET can only be deleted individually.
|
|
*/
|
|
VNET_DEFINE(u_int32_t, set_disable);
|
|
#define V_set_disable VNET(set_disable)
|
|
|
|
VNET_DEFINE(int, fw_verbose);
|
|
/* counter for ipfw_log(NULL...) */
|
|
VNET_DEFINE(u_int64_t, norule_counter);
|
|
VNET_DEFINE(int, verbose_limit);
|
|
|
|
/* layer3_chain contains the list of rules for layer 3 */
|
|
VNET_DEFINE(struct ip_fw_chain, layer3_chain);
|
|
|
|
/* ipfw_vnet_ready controls when we are open for business */
|
|
VNET_DEFINE(int, ipfw_vnet_ready) = 0;
|
|
|
|
VNET_DEFINE(int, ipfw_nat_ready) = 0;
|
|
|
|
ipfw_nat_t *ipfw_nat_ptr = NULL;
|
|
struct cfg_nat *(*lookup_nat_ptr)(struct nat_list *, int);
|
|
ipfw_nat_cfg_t *ipfw_nat_cfg_ptr;
|
|
ipfw_nat_cfg_t *ipfw_nat_del_ptr;
|
|
ipfw_nat_cfg_t *ipfw_nat_get_cfg_ptr;
|
|
ipfw_nat_cfg_t *ipfw_nat_get_log_ptr;
|
|
|
|
#ifdef SYSCTL_NODE
|
|
uint32_t dummy_def = IPFW_DEFAULT_RULE;
|
|
static int sysctl_ipfw_table_num(SYSCTL_HANDLER_ARGS);
|
|
static int sysctl_ipfw_tables_sets(SYSCTL_HANDLER_ARGS);
|
|
|
|
SYSBEGIN(f3)
|
|
|
|
SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
|
|
"Firewall");
|
|
SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, one_pass,
|
|
CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_one_pass), 0,
|
|
"Only do a single pass through ipfw when using dummynet(4)");
|
|
SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, autoinc_step,
|
|
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(autoinc_step), 0,
|
|
"Rule number auto-increment step");
|
|
SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose,
|
|
CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_verbose), 0,
|
|
"Log matches to ipfw rules");
|
|
SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit,
|
|
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(verbose_limit), 0,
|
|
"Set upper limit of matches of ipfw rules logged");
|
|
SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, default_rule, CTLFLAG_RD,
|
|
&dummy_def, 0,
|
|
"The default/max possible rule number.");
|
|
SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, tables_max,
|
|
CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE,
|
|
0, 0, sysctl_ipfw_table_num, "IU",
|
|
"Maximum number of concurrently used tables");
|
|
SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, tables_sets,
|
|
CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE,
|
|
0, 0, sysctl_ipfw_tables_sets, "IU",
|
|
"Use per-set namespace for tables");
|
|
SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, default_to_accept, CTLFLAG_RDTUN,
|
|
&default_to_accept, 0,
|
|
"Make the default rule accept all packets.");
|
|
TUNABLE_INT("net.inet.ip.fw.tables_max", (int *)&default_fw_tables);
|
|
SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, static_count,
|
|
CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(layer3_chain.n_rules), 0,
|
|
"Number of static rules");
|
|
|
|
#ifdef INET6
|
|
SYSCTL_DECL(_net_inet6_ip6);
|
|
SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, fw, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
|
|
"Firewall");
|
|
SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, deny_unknown_exthdrs,
|
|
CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE,
|
|
&VNET_NAME(fw_deny_unknown_exthdrs), 0,
|
|
"Deny packets with unknown IPv6 Extension Headers");
|
|
SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, permit_single_frag6,
|
|
CTLFLAG_VNET | CTLFLAG_RW | CTLFLAG_SECURE,
|
|
&VNET_NAME(fw_permit_single_frag6), 0,
|
|
"Permit single packet IPv6 fragments");
|
|
#endif /* INET6 */
|
|
|
|
SYSEND
|
|
|
|
#endif /* SYSCTL_NODE */
|
|
|
|
/*
|
|
* Some macros used in the various matching options.
|
|
* L3HDR maps an ipv4 pointer into a layer3 header pointer of type T
|
|
* Other macros just cast void * into the appropriate type
|
|
*/
|
|
#define L3HDR(T, ip) ((T *)((u_int32_t *)(ip) + (ip)->ip_hl))
|
|
#define TCP(p) ((struct tcphdr *)(p))
|
|
#define SCTP(p) ((struct sctphdr *)(p))
|
|
#define UDP(p) ((struct udphdr *)(p))
|
|
#define ICMP(p) ((struct icmphdr *)(p))
|
|
#define ICMP6(p) ((struct icmp6_hdr *)(p))
|
|
|
|
static __inline int
|
|
icmptype_match(struct icmphdr *icmp, ipfw_insn_u32 *cmd)
|
|
{
|
|
int type = icmp->icmp_type;
|
|
|
|
return (type <= ICMP_MAXTYPE && (cmd->d[0] & (1<<type)) );
|
|
}
|
|
|
|
#define TT ( (1 << ICMP_ECHO) | (1 << ICMP_ROUTERSOLICIT) | \
|
|
(1 << ICMP_TSTAMP) | (1 << ICMP_IREQ) | (1 << ICMP_MASKREQ) )
|
|
|
|
static int
|
|
is_icmp_query(struct icmphdr *icmp)
|
|
{
|
|
int type = icmp->icmp_type;
|
|
|
|
return (type <= ICMP_MAXTYPE && (TT & (1<<type)) );
|
|
}
|
|
#undef TT
|
|
|
|
/*
|
|
* The following checks use two arrays of 8 or 16 bits to store the
|
|
* bits that we want set or clear, respectively. They are in the
|
|
* low and high half of cmd->arg1 or cmd->d[0].
|
|
*
|
|
* We scan options and store the bits we find set. We succeed if
|
|
*
|
|
* (want_set & ~bits) == 0 && (want_clear & ~bits) == want_clear
|
|
*
|
|
* The code is sometimes optimized not to store additional variables.
|
|
*/
|
|
|
|
static int
|
|
flags_match(ipfw_insn *cmd, u_int8_t bits)
|
|
{
|
|
u_char want_clear;
|
|
bits = ~bits;
|
|
|
|
if ( ((cmd->arg1 & 0xff) & bits) != 0)
|
|
return 0; /* some bits we want set were clear */
|
|
want_clear = (cmd->arg1 >> 8) & 0xff;
|
|
if ( (want_clear & bits) != want_clear)
|
|
return 0; /* some bits we want clear were set */
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
ipopts_match(struct ip *ip, ipfw_insn *cmd)
|
|
{
|
|
int optlen, bits = 0;
|
|
u_char *cp = (u_char *)(ip + 1);
|
|
int x = (ip->ip_hl << 2) - sizeof (struct ip);
|
|
|
|
for (; x > 0; x -= optlen, cp += optlen) {
|
|
int opt = cp[IPOPT_OPTVAL];
|
|
|
|
if (opt == IPOPT_EOL)
|
|
break;
|
|
if (opt == IPOPT_NOP)
|
|
optlen = 1;
|
|
else {
|
|
optlen = cp[IPOPT_OLEN];
|
|
if (optlen <= 0 || optlen > x)
|
|
return 0; /* invalid or truncated */
|
|
}
|
|
switch (opt) {
|
|
default:
|
|
break;
|
|
|
|
case IPOPT_LSRR:
|
|
bits |= IP_FW_IPOPT_LSRR;
|
|
break;
|
|
|
|
case IPOPT_SSRR:
|
|
bits |= IP_FW_IPOPT_SSRR;
|
|
break;
|
|
|
|
case IPOPT_RR:
|
|
bits |= IP_FW_IPOPT_RR;
|
|
break;
|
|
|
|
case IPOPT_TS:
|
|
bits |= IP_FW_IPOPT_TS;
|
|
break;
|
|
}
|
|
}
|
|
return (flags_match(cmd, bits));
|
|
}
|
|
|
|
/*
|
|
* Parse TCP options. The logic copied from tcp_dooptions().
|
|
*/
|
|
static int
|
|
tcpopts_parse(const struct tcphdr *tcp, uint16_t *mss)
|
|
{
|
|
const u_char *cp = (const u_char *)(tcp + 1);
|
|
int optlen, bits = 0;
|
|
int cnt = (tcp->th_off << 2) - sizeof(struct tcphdr);
|
|
|
|
for (; cnt > 0; cnt -= optlen, cp += optlen) {
|
|
int opt = cp[0];
|
|
if (opt == TCPOPT_EOL)
|
|
break;
|
|
if (opt == TCPOPT_NOP)
|
|
optlen = 1;
|
|
else {
|
|
if (cnt < 2)
|
|
break;
|
|
optlen = cp[1];
|
|
if (optlen < 2 || optlen > cnt)
|
|
break;
|
|
}
|
|
|
|
switch (opt) {
|
|
default:
|
|
break;
|
|
|
|
case TCPOPT_MAXSEG:
|
|
if (optlen != TCPOLEN_MAXSEG)
|
|
break;
|
|
bits |= IP_FW_TCPOPT_MSS;
|
|
if (mss != NULL)
|
|
*mss = be16dec(cp + 2);
|
|
break;
|
|
|
|
case TCPOPT_WINDOW:
|
|
if (optlen == TCPOLEN_WINDOW)
|
|
bits |= IP_FW_TCPOPT_WINDOW;
|
|
break;
|
|
|
|
case TCPOPT_SACK_PERMITTED:
|
|
if (optlen == TCPOLEN_SACK_PERMITTED)
|
|
bits |= IP_FW_TCPOPT_SACK;
|
|
break;
|
|
|
|
case TCPOPT_SACK:
|
|
if (optlen > 2 && (optlen - 2) % TCPOLEN_SACK == 0)
|
|
bits |= IP_FW_TCPOPT_SACK;
|
|
break;
|
|
|
|
case TCPOPT_TIMESTAMP:
|
|
if (optlen == TCPOLEN_TIMESTAMP)
|
|
bits |= IP_FW_TCPOPT_TS;
|
|
break;
|
|
}
|
|
}
|
|
return (bits);
|
|
}
|
|
|
|
static int
|
|
tcpopts_match(struct tcphdr *tcp, ipfw_insn *cmd)
|
|
{
|
|
|
|
return (flags_match(cmd, tcpopts_parse(tcp, NULL)));
|
|
}
|
|
|
|
static int
|
|
iface_match(struct ifnet *ifp, ipfw_insn_if *cmd, struct ip_fw_chain *chain,
|
|
uint32_t *tablearg)
|
|
{
|
|
|
|
if (ifp == NULL) /* no iface with this packet, match fails */
|
|
return (0);
|
|
|
|
/* Check by name or by IP address */
|
|
if (cmd->name[0] != '\0') { /* match by name */
|
|
if (cmd->name[0] == '\1') /* use tablearg to match */
|
|
return ipfw_lookup_table(chain, cmd->p.kidx, 0,
|
|
&ifp->if_index, tablearg);
|
|
/* Check name */
|
|
if (cmd->p.glob) {
|
|
if (fnmatch(cmd->name, ifp->if_xname, 0) == 0)
|
|
return(1);
|
|
} else {
|
|
if (strncmp(ifp->if_xname, cmd->name, IFNAMSIZ) == 0)
|
|
return(1);
|
|
}
|
|
} else {
|
|
#if !defined(USERSPACE) && defined(__FreeBSD__) /* and OSX too ? */
|
|
struct ifaddr *ia;
|
|
|
|
NET_EPOCH_ASSERT();
|
|
|
|
CK_STAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) {
|
|
if (ia->ifa_addr->sa_family != AF_INET)
|
|
continue;
|
|
if (cmd->p.ip.s_addr == ((struct sockaddr_in *)
|
|
(ia->ifa_addr))->sin_addr.s_addr)
|
|
return (1); /* match */
|
|
}
|
|
#endif /* __FreeBSD__ */
|
|
}
|
|
return(0); /* no match, fail ... */
|
|
}
|
|
|
|
/*
|
|
* The verify_path function checks if a route to the src exists and
|
|
* if it is reachable via ifp (when provided).
|
|
*
|
|
* The 'verrevpath' option checks that the interface that an IP packet
|
|
* arrives on is the same interface that traffic destined for the
|
|
* packet's source address would be routed out of.
|
|
* The 'versrcreach' option just checks that the source address is
|
|
* reachable via any route (except default) in the routing table.
|
|
* These two are a measure to block forged packets. This is also
|
|
* commonly known as "anti-spoofing" or Unicast Reverse Path
|
|
* Forwarding (Unicast RFP) in Cisco-ese. The name of the knobs
|
|
* is purposely reminiscent of the Cisco IOS command,
|
|
*
|
|
* ip verify unicast reverse-path
|
|
* ip verify unicast source reachable-via any
|
|
*
|
|
* which implements the same functionality. But note that the syntax
|
|
* is misleading, and the check may be performed on all IP packets
|
|
* whether unicast, multicast, or broadcast.
|
|
*/
|
|
static int
|
|
verify_path(struct in_addr src, struct ifnet *ifp, u_int fib)
|
|
{
|
|
#if defined(USERSPACE) || !defined(__FreeBSD__)
|
|
return 0;
|
|
#else
|
|
struct nhop_object *nh;
|
|
|
|
nh = fib4_lookup(fib, src, 0, NHR_NONE, 0);
|
|
if (nh == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* If ifp is provided, check for equality with rtentry.
|
|
* We should use rt->rt_ifa->ifa_ifp, instead of rt->rt_ifp,
|
|
* in order to pass packets injected back by if_simloop():
|
|
* routing entry (via lo0) for our own address
|
|
* may exist, so we need to handle routing assymetry.
|
|
*/
|
|
if (ifp != NULL && ifp != nh->nh_aifp)
|
|
return (0);
|
|
|
|
/* if no ifp provided, check if rtentry is not default route */
|
|
if (ifp == NULL && (nh->nh_flags & NHF_DEFAULT) != 0)
|
|
return (0);
|
|
|
|
/* or if this is a blackhole/reject route */
|
|
if (ifp == NULL && (nh->nh_flags & (NHF_REJECT|NHF_BLACKHOLE)) != 0)
|
|
return (0);
|
|
|
|
/* found valid route */
|
|
return 1;
|
|
#endif /* __FreeBSD__ */
|
|
}
|
|
|
|
/*
|
|
* Generate an SCTP packet containing an ABORT chunk. The verification tag
|
|
* is given by vtag. The T-bit is set in the ABORT chunk if and only if
|
|
* reflected is not 0.
|
|
*/
|
|
|
|
static struct mbuf *
|
|
ipfw_send_abort(struct mbuf *replyto, struct ipfw_flow_id *id, u_int32_t vtag,
|
|
int reflected)
|
|
{
|
|
struct mbuf *m;
|
|
struct ip *ip;
|
|
#ifdef INET6
|
|
struct ip6_hdr *ip6;
|
|
#endif
|
|
struct sctphdr *sctp;
|
|
struct sctp_chunkhdr *chunk;
|
|
u_int16_t hlen, plen, tlen;
|
|
|
|
MGETHDR(m, M_NOWAIT, MT_DATA);
|
|
if (m == NULL)
|
|
return (NULL);
|
|
|
|
M_SETFIB(m, id->fib);
|
|
#ifdef MAC
|
|
if (replyto != NULL)
|
|
mac_netinet_firewall_reply(replyto, m);
|
|
else
|
|
mac_netinet_firewall_send(m);
|
|
#else
|
|
(void)replyto; /* don't warn about unused arg */
|
|
#endif
|
|
|
|
switch (id->addr_type) {
|
|
case 4:
|
|
hlen = sizeof(struct ip);
|
|
break;
|
|
#ifdef INET6
|
|
case 6:
|
|
hlen = sizeof(struct ip6_hdr);
|
|
break;
|
|
#endif
|
|
default:
|
|
/* XXX: log me?!? */
|
|
FREE_PKT(m);
|
|
return (NULL);
|
|
}
|
|
plen = sizeof(struct sctphdr) + sizeof(struct sctp_chunkhdr);
|
|
tlen = hlen + plen;
|
|
m->m_data += max_linkhdr;
|
|
m->m_flags |= M_SKIP_FIREWALL;
|
|
m->m_pkthdr.len = m->m_len = tlen;
|
|
m->m_pkthdr.rcvif = NULL;
|
|
bzero(m->m_data, tlen);
|
|
|
|
switch (id->addr_type) {
|
|
case 4:
|
|
ip = mtod(m, struct ip *);
|
|
|
|
ip->ip_v = 4;
|
|
ip->ip_hl = sizeof(struct ip) >> 2;
|
|
ip->ip_tos = IPTOS_LOWDELAY;
|
|
ip->ip_len = htons(tlen);
|
|
ip->ip_id = htons(0);
|
|
ip->ip_off = htons(0);
|
|
ip->ip_ttl = V_ip_defttl;
|
|
ip->ip_p = IPPROTO_SCTP;
|
|
ip->ip_sum = 0;
|
|
ip->ip_src.s_addr = htonl(id->dst_ip);
|
|
ip->ip_dst.s_addr = htonl(id->src_ip);
|
|
|
|
sctp = (struct sctphdr *)(ip + 1);
|
|
break;
|
|
#ifdef INET6
|
|
case 6:
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
|
|
ip6->ip6_vfc = IPV6_VERSION;
|
|
ip6->ip6_plen = htons(plen);
|
|
ip6->ip6_nxt = IPPROTO_SCTP;
|
|
ip6->ip6_hlim = IPV6_DEFHLIM;
|
|
ip6->ip6_src = id->dst_ip6;
|
|
ip6->ip6_dst = id->src_ip6;
|
|
|
|
sctp = (struct sctphdr *)(ip6 + 1);
|
|
break;
|
|
#endif
|
|
}
|
|
|
|
sctp->src_port = htons(id->dst_port);
|
|
sctp->dest_port = htons(id->src_port);
|
|
sctp->v_tag = htonl(vtag);
|
|
sctp->checksum = htonl(0);
|
|
|
|
chunk = (struct sctp_chunkhdr *)(sctp + 1);
|
|
chunk->chunk_type = SCTP_ABORT_ASSOCIATION;
|
|
chunk->chunk_flags = 0;
|
|
if (reflected != 0) {
|
|
chunk->chunk_flags |= SCTP_HAD_NO_TCB;
|
|
}
|
|
chunk->chunk_length = htons(sizeof(struct sctp_chunkhdr));
|
|
|
|
sctp->checksum = sctp_calculate_cksum(m, hlen);
|
|
|
|
return (m);
|
|
}
|
|
|
|
/*
|
|
* Generate a TCP packet, containing either a RST or a keepalive.
|
|
* When flags & TH_RST, we are sending a RST packet, because of a
|
|
* "reset" action matched the packet.
|
|
* Otherwise we are sending a keepalive, and flags & TH_
|
|
* The 'replyto' mbuf is the mbuf being replied to, if any, and is required
|
|
* so that MAC can label the reply appropriately.
|
|
*/
|
|
struct mbuf *
|
|
ipfw_send_pkt(struct mbuf *replyto, struct ipfw_flow_id *id, u_int32_t seq,
|
|
u_int32_t ack, int flags)
|
|
{
|
|
struct mbuf *m = NULL; /* stupid compiler */
|
|
struct ip *h = NULL; /* stupid compiler */
|
|
#ifdef INET6
|
|
struct ip6_hdr *h6 = NULL;
|
|
#endif
|
|
struct tcphdr *th = NULL;
|
|
int len, dir;
|
|
|
|
MGETHDR(m, M_NOWAIT, MT_DATA);
|
|
if (m == NULL)
|
|
return (NULL);
|
|
|
|
M_SETFIB(m, id->fib);
|
|
#ifdef MAC
|
|
if (replyto != NULL)
|
|
mac_netinet_firewall_reply(replyto, m);
|
|
else
|
|
mac_netinet_firewall_send(m);
|
|
#else
|
|
(void)replyto; /* don't warn about unused arg */
|
|
#endif
|
|
|
|
switch (id->addr_type) {
|
|
case 4:
|
|
len = sizeof(struct ip) + sizeof(struct tcphdr);
|
|
break;
|
|
#ifdef INET6
|
|
case 6:
|
|
len = sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
|
|
break;
|
|
#endif
|
|
default:
|
|
/* XXX: log me?!? */
|
|
FREE_PKT(m);
|
|
return (NULL);
|
|
}
|
|
dir = ((flags & (TH_SYN | TH_RST)) == TH_SYN);
|
|
|
|
m->m_data += max_linkhdr;
|
|
m->m_flags |= M_SKIP_FIREWALL;
|
|
m->m_pkthdr.len = m->m_len = len;
|
|
m->m_pkthdr.rcvif = NULL;
|
|
bzero(m->m_data, len);
|
|
|
|
switch (id->addr_type) {
|
|
case 4:
|
|
h = mtod(m, struct ip *);
|
|
|
|
/* prepare for checksum */
|
|
h->ip_p = IPPROTO_TCP;
|
|
h->ip_len = htons(sizeof(struct tcphdr));
|
|
if (dir) {
|
|
h->ip_src.s_addr = htonl(id->src_ip);
|
|
h->ip_dst.s_addr = htonl(id->dst_ip);
|
|
} else {
|
|
h->ip_src.s_addr = htonl(id->dst_ip);
|
|
h->ip_dst.s_addr = htonl(id->src_ip);
|
|
}
|
|
|
|
th = (struct tcphdr *)(h + 1);
|
|
break;
|
|
#ifdef INET6
|
|
case 6:
|
|
h6 = mtod(m, struct ip6_hdr *);
|
|
|
|
/* prepare for checksum */
|
|
h6->ip6_nxt = IPPROTO_TCP;
|
|
h6->ip6_plen = htons(sizeof(struct tcphdr));
|
|
if (dir) {
|
|
h6->ip6_src = id->src_ip6;
|
|
h6->ip6_dst = id->dst_ip6;
|
|
} else {
|
|
h6->ip6_src = id->dst_ip6;
|
|
h6->ip6_dst = id->src_ip6;
|
|
}
|
|
|
|
th = (struct tcphdr *)(h6 + 1);
|
|
break;
|
|
#endif
|
|
}
|
|
|
|
if (dir) {
|
|
th->th_sport = htons(id->src_port);
|
|
th->th_dport = htons(id->dst_port);
|
|
} else {
|
|
th->th_sport = htons(id->dst_port);
|
|
th->th_dport = htons(id->src_port);
|
|
}
|
|
th->th_off = sizeof(struct tcphdr) >> 2;
|
|
|
|
if (flags & TH_RST) {
|
|
if (flags & TH_ACK) {
|
|
th->th_seq = htonl(ack);
|
|
th->th_flags = TH_RST;
|
|
} else {
|
|
if (flags & TH_SYN)
|
|
seq++;
|
|
th->th_ack = htonl(seq);
|
|
th->th_flags = TH_RST | TH_ACK;
|
|
}
|
|
} else {
|
|
/*
|
|
* Keepalive - use caller provided sequence numbers
|
|
*/
|
|
th->th_seq = htonl(seq);
|
|
th->th_ack = htonl(ack);
|
|
th->th_flags = TH_ACK;
|
|
}
|
|
|
|
switch (id->addr_type) {
|
|
case 4:
|
|
th->th_sum = in_cksum(m, len);
|
|
|
|
/* finish the ip header */
|
|
h->ip_v = 4;
|
|
h->ip_hl = sizeof(*h) >> 2;
|
|
h->ip_tos = IPTOS_LOWDELAY;
|
|
h->ip_off = htons(0);
|
|
h->ip_len = htons(len);
|
|
h->ip_ttl = V_ip_defttl;
|
|
h->ip_sum = 0;
|
|
break;
|
|
#ifdef INET6
|
|
case 6:
|
|
th->th_sum = in6_cksum(m, IPPROTO_TCP, sizeof(*h6),
|
|
sizeof(struct tcphdr));
|
|
|
|
/* finish the ip6 header */
|
|
h6->ip6_vfc |= IPV6_VERSION;
|
|
h6->ip6_hlim = IPV6_DEFHLIM;
|
|
break;
|
|
#endif
|
|
}
|
|
|
|
return (m);
|
|
}
|
|
|
|
#ifdef INET6
|
|
/*
|
|
* ipv6 specific rules here...
|
|
*/
|
|
static __inline int
|
|
icmp6type_match(int type, ipfw_insn_u32 *cmd)
|
|
{
|
|
return (type <= ICMP6_MAXTYPE && (cmd->d[type/32] & (1<<(type%32)) ) );
|
|
}
|
|
|
|
static int
|
|
flow6id_match(int curr_flow, ipfw_insn_u32 *cmd)
|
|
{
|
|
int i;
|
|
for (i=0; i <= cmd->o.arg1; ++i)
|
|
if (curr_flow == cmd->d[i])
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/* support for IP6_*_ME opcodes */
|
|
static const struct in6_addr lla_mask = {{{
|
|
0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff,
|
|
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
|
|
}}};
|
|
|
|
static int
|
|
ipfw_localip6(struct in6_addr *in6)
|
|
{
|
|
struct rm_priotracker in6_ifa_tracker;
|
|
struct in6_ifaddr *ia;
|
|
|
|
if (IN6_IS_ADDR_MULTICAST(in6))
|
|
return (0);
|
|
|
|
if (!IN6_IS_ADDR_LINKLOCAL(in6))
|
|
return (in6_localip(in6));
|
|
|
|
IN6_IFADDR_RLOCK(&in6_ifa_tracker);
|
|
CK_STAILQ_FOREACH(ia, &V_in6_ifaddrhead, ia_link) {
|
|
if (!IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr))
|
|
continue;
|
|
if (IN6_ARE_MASKED_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
|
|
in6, &lla_mask)) {
|
|
IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
|
|
return (1);
|
|
}
|
|
}
|
|
IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
verify_path6(struct in6_addr *src, struct ifnet *ifp, u_int fib)
|
|
{
|
|
struct nhop_object *nh;
|
|
|
|
if (IN6_IS_SCOPE_LINKLOCAL(src))
|
|
return (1);
|
|
|
|
nh = fib6_lookup(fib, src, 0, NHR_NONE, 0);
|
|
if (nh == NULL)
|
|
return (0);
|
|
|
|
/* If ifp is provided, check for equality with route table. */
|
|
if (ifp != NULL && ifp != nh->nh_aifp)
|
|
return (0);
|
|
|
|
/* if no ifp provided, check if rtentry is not default route */
|
|
if (ifp == NULL && (nh->nh_flags & NHF_DEFAULT) != 0)
|
|
return (0);
|
|
|
|
/* or if this is a blackhole/reject route */
|
|
if (ifp == NULL && (nh->nh_flags & (NHF_REJECT|NHF_BLACKHOLE)) != 0)
|
|
return (0);
|
|
|
|
/* found valid route */
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
is_icmp6_query(int icmp6_type)
|
|
{
|
|
if ((icmp6_type <= ICMP6_MAXTYPE) &&
|
|
(icmp6_type == ICMP6_ECHO_REQUEST ||
|
|
icmp6_type == ICMP6_MEMBERSHIP_QUERY ||
|
|
icmp6_type == ICMP6_WRUREQUEST ||
|
|
icmp6_type == ICMP6_FQDN_QUERY ||
|
|
icmp6_type == ICMP6_NI_QUERY))
|
|
return (1);
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
map_icmp_unreach(int code)
|
|
{
|
|
|
|
/* RFC 7915 p4.2 */
|
|
switch (code) {
|
|
case ICMP_UNREACH_NET:
|
|
case ICMP_UNREACH_HOST:
|
|
case ICMP_UNREACH_SRCFAIL:
|
|
case ICMP_UNREACH_NET_UNKNOWN:
|
|
case ICMP_UNREACH_HOST_UNKNOWN:
|
|
case ICMP_UNREACH_TOSNET:
|
|
case ICMP_UNREACH_TOSHOST:
|
|
return (ICMP6_DST_UNREACH_NOROUTE);
|
|
case ICMP_UNREACH_PORT:
|
|
return (ICMP6_DST_UNREACH_NOPORT);
|
|
default:
|
|
/*
|
|
* Map the rest of codes into admit prohibited.
|
|
* XXX: unreach proto should be mapped into ICMPv6
|
|
* parameter problem, but we use only unreach type.
|
|
*/
|
|
return (ICMP6_DST_UNREACH_ADMIN);
|
|
}
|
|
}
|
|
|
|
static void
|
|
send_reject6(struct ip_fw_args *args, int code, u_int hlen, struct ip6_hdr *ip6)
|
|
{
|
|
struct mbuf *m;
|
|
|
|
m = args->m;
|
|
if (code == ICMP6_UNREACH_RST && args->f_id.proto == IPPROTO_TCP) {
|
|
struct tcphdr *tcp;
|
|
tcp = (struct tcphdr *)((char *)ip6 + hlen);
|
|
|
|
if ((tcp->th_flags & TH_RST) == 0) {
|
|
struct mbuf *m0;
|
|
m0 = ipfw_send_pkt(args->m, &(args->f_id),
|
|
ntohl(tcp->th_seq), ntohl(tcp->th_ack),
|
|
tcp->th_flags | TH_RST);
|
|
if (m0 != NULL)
|
|
ip6_output(m0, NULL, NULL, 0, NULL, NULL,
|
|
NULL);
|
|
}
|
|
FREE_PKT(m);
|
|
} else if (code == ICMP6_UNREACH_ABORT &&
|
|
args->f_id.proto == IPPROTO_SCTP) {
|
|
struct mbuf *m0;
|
|
struct sctphdr *sctp;
|
|
u_int32_t v_tag;
|
|
int reflected;
|
|
|
|
sctp = (struct sctphdr *)((char *)ip6 + hlen);
|
|
reflected = 1;
|
|
v_tag = ntohl(sctp->v_tag);
|
|
/* Investigate the first chunk header if available */
|
|
if (m->m_len >= hlen + sizeof(struct sctphdr) +
|
|
sizeof(struct sctp_chunkhdr)) {
|
|
struct sctp_chunkhdr *chunk;
|
|
|
|
chunk = (struct sctp_chunkhdr *)(sctp + 1);
|
|
switch (chunk->chunk_type) {
|
|
case SCTP_INITIATION:
|
|
/*
|
|
* Packets containing an INIT chunk MUST have
|
|
* a zero v-tag.
|
|
*/
|
|
if (v_tag != 0) {
|
|
v_tag = 0;
|
|
break;
|
|
}
|
|
/* INIT chunk MUST NOT be bundled */
|
|
if (m->m_pkthdr.len >
|
|
hlen + sizeof(struct sctphdr) +
|
|
ntohs(chunk->chunk_length) + 3) {
|
|
break;
|
|
}
|
|
/* Use the initiate tag if available */
|
|
if ((m->m_len >= hlen + sizeof(struct sctphdr) +
|
|
sizeof(struct sctp_chunkhdr) +
|
|
offsetof(struct sctp_init, a_rwnd))) {
|
|
struct sctp_init *init;
|
|
|
|
init = (struct sctp_init *)(chunk + 1);
|
|
v_tag = ntohl(init->initiate_tag);
|
|
reflected = 0;
|
|
}
|
|
break;
|
|
case SCTP_ABORT_ASSOCIATION:
|
|
/*
|
|
* If the packet contains an ABORT chunk, don't
|
|
* reply.
|
|
* XXX: We should search through all chunks,
|
|
* but do not do that to avoid attacks.
|
|
*/
|
|
v_tag = 0;
|
|
break;
|
|
}
|
|
}
|
|
if (v_tag == 0) {
|
|
m0 = NULL;
|
|
} else {
|
|
m0 = ipfw_send_abort(args->m, &(args->f_id), v_tag,
|
|
reflected);
|
|
}
|
|
if (m0 != NULL)
|
|
ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL);
|
|
FREE_PKT(m);
|
|
} else if (code != ICMP6_UNREACH_RST && code != ICMP6_UNREACH_ABORT) {
|
|
/* Send an ICMPv6 unreach. */
|
|
#if 0
|
|
/*
|
|
* Unlike above, the mbufs need to line up with the ip6 hdr,
|
|
* as the contents are read. We need to m_adj() the
|
|
* needed amount.
|
|
* The mbuf will however be thrown away so we can adjust it.
|
|
* Remember we did an m_pullup on it already so we
|
|
* can make some assumptions about contiguousness.
|
|
*/
|
|
if (args->L3offset)
|
|
m_adj(m, args->L3offset);
|
|
#endif
|
|
icmp6_error(m, ICMP6_DST_UNREACH, code, 0);
|
|
} else
|
|
FREE_PKT(m);
|
|
|
|
args->m = NULL;
|
|
}
|
|
|
|
#endif /* INET6 */
|
|
|
|
/*
|
|
* sends a reject message, consuming the mbuf passed as an argument.
|
|
*/
|
|
static void
|
|
send_reject(struct ip_fw_args *args, const ipfw_insn *cmd, int iplen,
|
|
struct ip *ip)
|
|
{
|
|
int code, mtu;
|
|
|
|
code = cmd->arg1;
|
|
if (code == ICMP_UNREACH_NEEDFRAG &&
|
|
cmd->len == F_INSN_SIZE(ipfw_insn_u16))
|
|
mtu = ((const ipfw_insn_u16 *)cmd)->ports[0];
|
|
else
|
|
mtu = 0;
|
|
|
|
#if 0
|
|
/* XXX When ip is not guaranteed to be at mtod() we will
|
|
* need to account for this */
|
|
* The mbuf will however be thrown away so we can adjust it.
|
|
* Remember we did an m_pullup on it already so we
|
|
* can make some assumptions about contiguousness.
|
|
*/
|
|
if (args->L3offset)
|
|
m_adj(m, args->L3offset);
|
|
#endif
|
|
if (code != ICMP_REJECT_RST && code != ICMP_REJECT_ABORT) {
|
|
/* Send an ICMP unreach */
|
|
icmp_error(args->m, ICMP_UNREACH, code, 0L, mtu);
|
|
} else if (code == ICMP_REJECT_RST && args->f_id.proto == IPPROTO_TCP) {
|
|
struct tcphdr *const tcp =
|
|
L3HDR(struct tcphdr, mtod(args->m, struct ip *));
|
|
if ( (tcp->th_flags & TH_RST) == 0) {
|
|
struct mbuf *m;
|
|
m = ipfw_send_pkt(args->m, &(args->f_id),
|
|
ntohl(tcp->th_seq), ntohl(tcp->th_ack),
|
|
tcp->th_flags | TH_RST);
|
|
if (m != NULL)
|
|
ip_output(m, NULL, NULL, 0, NULL, NULL);
|
|
}
|
|
FREE_PKT(args->m);
|
|
} else if (code == ICMP_REJECT_ABORT &&
|
|
args->f_id.proto == IPPROTO_SCTP) {
|
|
struct mbuf *m;
|
|
struct sctphdr *sctp;
|
|
struct sctp_chunkhdr *chunk;
|
|
struct sctp_init *init;
|
|
u_int32_t v_tag;
|
|
int reflected;
|
|
|
|
sctp = L3HDR(struct sctphdr, mtod(args->m, struct ip *));
|
|
reflected = 1;
|
|
v_tag = ntohl(sctp->v_tag);
|
|
if (iplen >= (ip->ip_hl << 2) + sizeof(struct sctphdr) +
|
|
sizeof(struct sctp_chunkhdr)) {
|
|
/* Look at the first chunk header if available */
|
|
chunk = (struct sctp_chunkhdr *)(sctp + 1);
|
|
switch (chunk->chunk_type) {
|
|
case SCTP_INITIATION:
|
|
/*
|
|
* Packets containing an INIT chunk MUST have
|
|
* a zero v-tag.
|
|
*/
|
|
if (v_tag != 0) {
|
|
v_tag = 0;
|
|
break;
|
|
}
|
|
/* INIT chunk MUST NOT be bundled */
|
|
if (iplen >
|
|
(ip->ip_hl << 2) + sizeof(struct sctphdr) +
|
|
ntohs(chunk->chunk_length) + 3) {
|
|
break;
|
|
}
|
|
/* Use the initiate tag if available */
|
|
if ((iplen >= (ip->ip_hl << 2) +
|
|
sizeof(struct sctphdr) +
|
|
sizeof(struct sctp_chunkhdr) +
|
|
offsetof(struct sctp_init, a_rwnd))) {
|
|
init = (struct sctp_init *)(chunk + 1);
|
|
v_tag = ntohl(init->initiate_tag);
|
|
reflected = 0;
|
|
}
|
|
break;
|
|
case SCTP_ABORT_ASSOCIATION:
|
|
/*
|
|
* If the packet contains an ABORT chunk, don't
|
|
* reply.
|
|
* XXX: We should search through all chunks,
|
|
* but do not do that to avoid attacks.
|
|
*/
|
|
v_tag = 0;
|
|
break;
|
|
}
|
|
}
|
|
if (v_tag == 0) {
|
|
m = NULL;
|
|
} else {
|
|
m = ipfw_send_abort(args->m, &(args->f_id), v_tag,
|
|
reflected);
|
|
}
|
|
if (m != NULL)
|
|
ip_output(m, NULL, NULL, 0, NULL, NULL);
|
|
FREE_PKT(args->m);
|
|
} else
|
|
FREE_PKT(args->m);
|
|
args->m = NULL;
|
|
}
|
|
|
|
/*
|
|
* Support for uid/gid/jail lookup. These tests are expensive
|
|
* (because we may need to look into the list of active sockets)
|
|
* so we cache the results. ugid_lookupp is 0 if we have not
|
|
* yet done a lookup, 1 if we succeeded, and -1 if we tried
|
|
* and failed. The function always returns the match value.
|
|
* We could actually spare the variable and use *uc, setting
|
|
* it to '(void *)check_uidgid if we have no info, NULL if
|
|
* we tried and failed, or any other value if successful.
|
|
*/
|
|
static int
|
|
check_uidgid(ipfw_insn_u32 *insn, struct ip_fw_args *args, int *ugid_lookupp,
|
|
struct ucred **uc)
|
|
{
|
|
#if defined(USERSPACE)
|
|
return 0; // not supported in userspace
|
|
#else
|
|
#ifndef __FreeBSD__
|
|
/* XXX */
|
|
return cred_check(insn, proto, oif,
|
|
dst_ip, dst_port, src_ip, src_port,
|
|
(struct bsd_ucred *)uc, ugid_lookupp, ((struct mbuf *)inp)->m_skb);
|
|
#else /* FreeBSD */
|
|
struct in_addr src_ip, dst_ip;
|
|
struct inpcbinfo *pi;
|
|
struct ipfw_flow_id *id;
|
|
struct inpcb *pcb, *inp;
|
|
int lookupflags;
|
|
int match;
|
|
|
|
id = &args->f_id;
|
|
inp = args->inp;
|
|
|
|
/*
|
|
* Check to see if the UDP or TCP stack supplied us with
|
|
* the PCB. If so, rather then holding a lock and looking
|
|
* up the PCB, we can use the one that was supplied.
|
|
*/
|
|
if (inp && *ugid_lookupp == 0) {
|
|
INP_LOCK_ASSERT(inp);
|
|
if (inp->inp_socket != NULL) {
|
|
*uc = crhold(inp->inp_cred);
|
|
*ugid_lookupp = 1;
|
|
} else
|
|
*ugid_lookupp = -1;
|
|
}
|
|
/*
|
|
* If we have already been here and the packet has no
|
|
* PCB entry associated with it, then we can safely
|
|
* assume that this is a no match.
|
|
*/
|
|
if (*ugid_lookupp == -1)
|
|
return (0);
|
|
if (id->proto == IPPROTO_TCP) {
|
|
lookupflags = 0;
|
|
pi = &V_tcbinfo;
|
|
} else if (id->proto == IPPROTO_UDP) {
|
|
lookupflags = INPLOOKUP_WILDCARD;
|
|
pi = &V_udbinfo;
|
|
} else if (id->proto == IPPROTO_UDPLITE) {
|
|
lookupflags = INPLOOKUP_WILDCARD;
|
|
pi = &V_ulitecbinfo;
|
|
} else
|
|
return 0;
|
|
lookupflags |= INPLOOKUP_RLOCKPCB;
|
|
match = 0;
|
|
if (*ugid_lookupp == 0) {
|
|
if (id->addr_type == 6) {
|
|
#ifdef INET6
|
|
if (args->flags & IPFW_ARGS_IN)
|
|
pcb = in6_pcblookup_mbuf(pi,
|
|
&id->src_ip6, htons(id->src_port),
|
|
&id->dst_ip6, htons(id->dst_port),
|
|
lookupflags, NULL, args->m);
|
|
else
|
|
pcb = in6_pcblookup_mbuf(pi,
|
|
&id->dst_ip6, htons(id->dst_port),
|
|
&id->src_ip6, htons(id->src_port),
|
|
lookupflags, args->ifp, args->m);
|
|
#else
|
|
*ugid_lookupp = -1;
|
|
return (0);
|
|
#endif
|
|
} else {
|
|
src_ip.s_addr = htonl(id->src_ip);
|
|
dst_ip.s_addr = htonl(id->dst_ip);
|
|
if (args->flags & IPFW_ARGS_IN)
|
|
pcb = in_pcblookup_mbuf(pi,
|
|
src_ip, htons(id->src_port),
|
|
dst_ip, htons(id->dst_port),
|
|
lookupflags, NULL, args->m);
|
|
else
|
|
pcb = in_pcblookup_mbuf(pi,
|
|
dst_ip, htons(id->dst_port),
|
|
src_ip, htons(id->src_port),
|
|
lookupflags, args->ifp, args->m);
|
|
}
|
|
if (pcb != NULL) {
|
|
INP_RLOCK_ASSERT(pcb);
|
|
*uc = crhold(pcb->inp_cred);
|
|
*ugid_lookupp = 1;
|
|
INP_RUNLOCK(pcb);
|
|
}
|
|
if (*ugid_lookupp == 0) {
|
|
/*
|
|
* We tried and failed, set the variable to -1
|
|
* so we will not try again on this packet.
|
|
*/
|
|
*ugid_lookupp = -1;
|
|
return (0);
|
|
}
|
|
}
|
|
if (insn->o.opcode == O_UID)
|
|
match = ((*uc)->cr_uid == (uid_t)insn->d[0]);
|
|
else if (insn->o.opcode == O_GID)
|
|
match = groupmember((gid_t)insn->d[0], *uc);
|
|
else if (insn->o.opcode == O_JAIL)
|
|
match = ((*uc)->cr_prison->pr_id == (int)insn->d[0]);
|
|
return (match);
|
|
#endif /* __FreeBSD__ */
|
|
#endif /* not supported in userspace */
|
|
}
|
|
|
|
/*
|
|
* Helper function to set args with info on the rule after the matching
|
|
* one. slot is precise, whereas we guess rule_id as they are
|
|
* assigned sequentially.
|
|
*/
|
|
static inline void
|
|
set_match(struct ip_fw_args *args, int slot,
|
|
struct ip_fw_chain *chain)
|
|
{
|
|
args->rule.chain_id = chain->id;
|
|
args->rule.slot = slot + 1; /* we use 0 as a marker */
|
|
args->rule.rule_id = 1 + chain->map[slot]->id;
|
|
args->rule.rulenum = chain->map[slot]->rulenum;
|
|
args->flags |= IPFW_ARGS_REF;
|
|
}
|
|
|
|
static int
|
|
jump_lookup_pos(struct ip_fw_chain *chain, struct ip_fw *f, int num,
|
|
int tablearg, int jump_backwards)
|
|
{
|
|
int f_pos, i;
|
|
|
|
i = IP_FW_ARG_TABLEARG(chain, num, skipto);
|
|
/* make sure we do not jump backward */
|
|
if (jump_backwards == 0 && i <= f->rulenum)
|
|
i = f->rulenum + 1;
|
|
|
|
#ifndef LINEAR_SKIPTO
|
|
if (chain->idxmap != NULL)
|
|
f_pos = chain->idxmap[i];
|
|
else
|
|
f_pos = ipfw_find_rule(chain, i, 0);
|
|
#else
|
|
f_pos = chain->idxmap[i];
|
|
#endif /* LINEAR_SKIPTO */
|
|
|
|
return (f_pos);
|
|
}
|
|
|
|
|
|
#ifndef LINEAR_SKIPTO
|
|
/*
|
|
* Helper function to enable cached rule lookups using
|
|
* cache.id and cache.pos fields in ipfw rule.
|
|
*/
|
|
static int
|
|
jump_cached(struct ip_fw_chain *chain, struct ip_fw *f, int num,
|
|
int tablearg, int jump_backwards)
|
|
{
|
|
int f_pos;
|
|
|
|
/* Can't use cache with IP_FW_TARG */
|
|
if (num == IP_FW_TARG)
|
|
return jump_lookup_pos(chain, f, num, tablearg, jump_backwards);
|
|
|
|
/*
|
|
* If possible use cached f_pos (in f->cache.pos),
|
|
* whose version is written in f->cache.id (horrible hacks
|
|
* to avoid changing the ABI).
|
|
*
|
|
* Multiple threads can execute the same rule simultaneously,
|
|
* we need to ensure that cache.pos is updated before cache.id.
|
|
*/
|
|
|
|
#ifdef __LP64__
|
|
struct ip_fw_jump_cache cache;
|
|
|
|
cache.raw_value = f->cache.raw_value;
|
|
if (cache.id == chain->id)
|
|
return (cache.pos);
|
|
|
|
f_pos = jump_lookup_pos(chain, f, num, tablearg, jump_backwards);
|
|
|
|
cache.pos = f_pos;
|
|
cache.id = chain->id;
|
|
f->cache.raw_value = cache.raw_value;
|
|
#else
|
|
if (f->cache.id == chain->id) {
|
|
/* Load pos after id */
|
|
atomic_thread_fence_acq();
|
|
return (f->cache.pos);
|
|
}
|
|
|
|
f_pos = jump_lookup_pos(chain, f, num, tablearg, jump_backwards);
|
|
|
|
f->cache.pos = f_pos;
|
|
/* Store id after pos */
|
|
atomic_thread_fence_rel();
|
|
f->cache.id = chain->id;
|
|
#endif /* !__LP64__ */
|
|
return (f_pos);
|
|
}
|
|
#endif /* !LINEAR_SKIPTO */
|
|
|
|
#define TARG(k, f) IP_FW_ARG_TABLEARG(chain, k, f)
|
|
/*
|
|
* The main check routine for the firewall.
|
|
*
|
|
* All arguments are in args so we can modify them and return them
|
|
* back to the caller.
|
|
*
|
|
* Parameters:
|
|
*
|
|
* args->m (in/out) The packet; we set to NULL when/if we nuke it.
|
|
* Starts with the IP header.
|
|
* args->L3offset Number of bytes bypassed if we came from L2.
|
|
* e.g. often sizeof(eh) ** NOTYET **
|
|
* args->ifp Incoming or outgoing interface.
|
|
* args->divert_rule (in/out)
|
|
* Skip up to the first rule past this rule number;
|
|
* upon return, non-zero port number for divert or tee.
|
|
*
|
|
* args->rule Pointer to the last matching rule (in/out)
|
|
* args->next_hop Socket we are forwarding to (out).
|
|
* args->next_hop6 IPv6 next hop we are forwarding to (out).
|
|
* args->f_id Addresses grabbed from the packet (out)
|
|
* args->rule.info a cookie depending on rule action
|
|
*
|
|
* Return value:
|
|
*
|
|
* IP_FW_PASS the packet must be accepted
|
|
* IP_FW_DENY the packet must be dropped
|
|
* IP_FW_DIVERT divert packet, port in m_tag
|
|
* IP_FW_TEE tee packet, port in m_tag
|
|
* IP_FW_DUMMYNET to dummynet, pipe in args->cookie
|
|
* IP_FW_NETGRAPH into netgraph, cookie args->cookie
|
|
* args->rule contains the matching rule,
|
|
* args->rule.info has additional information.
|
|
*
|
|
*/
|
|
int
|
|
ipfw_chk(struct ip_fw_args *args)
|
|
{
|
|
|
|
/*
|
|
* Local variables holding state while processing a packet:
|
|
*
|
|
* IMPORTANT NOTE: to speed up the processing of rules, there
|
|
* are some assumption on the values of the variables, which
|
|
* are documented here. Should you change them, please check
|
|
* the implementation of the various instructions to make sure
|
|
* that they still work.
|
|
*
|
|
* m | args->m Pointer to the mbuf, as received from the caller.
|
|
* It may change if ipfw_chk() does an m_pullup, or if it
|
|
* consumes the packet because it calls send_reject().
|
|
* XXX This has to change, so that ipfw_chk() never modifies
|
|
* or consumes the buffer.
|
|
* OR
|
|
* args->mem Pointer to contigous memory chunk.
|
|
* ip Is the beginning of the ip(4 or 6) header.
|
|
* eh Ethernet header in case if input is Layer2.
|
|
*/
|
|
struct mbuf *m;
|
|
struct ip *ip;
|
|
struct ether_header *eh;
|
|
|
|
/*
|
|
* For rules which contain uid/gid or jail constraints, cache
|
|
* a copy of the users credentials after the pcb lookup has been
|
|
* executed. This will speed up the processing of rules with
|
|
* these types of constraints, as well as decrease contention
|
|
* on pcb related locks.
|
|
*/
|
|
#ifndef __FreeBSD__
|
|
struct bsd_ucred ucred_cache;
|
|
#else
|
|
struct ucred *ucred_cache = NULL;
|
|
#endif
|
|
int ucred_lookup = 0;
|
|
int f_pos = 0; /* index of current rule in the array */
|
|
int retval = 0;
|
|
struct ifnet *oif, *iif;
|
|
|
|
/*
|
|
* hlen The length of the IP header.
|
|
*/
|
|
u_int hlen = 0; /* hlen >0 means we have an IP pkt */
|
|
|
|
/*
|
|
* offset The offset of a fragment. offset != 0 means that
|
|
* we have a fragment at this offset of an IPv4 packet.
|
|
* offset == 0 means that (if this is an IPv4 packet)
|
|
* this is the first or only fragment.
|
|
* For IPv6 offset|ip6f_mf == 0 means there is no Fragment Header
|
|
* or there is a single packet fragment (fragment header added
|
|
* without needed). We will treat a single packet fragment as if
|
|
* there was no fragment header (or log/block depending on the
|
|
* V_fw_permit_single_frag6 sysctl setting).
|
|
*/
|
|
u_short offset = 0;
|
|
u_short ip6f_mf = 0;
|
|
|
|
/*
|
|
* Local copies of addresses. They are only valid if we have
|
|
* an IP packet.
|
|
*
|
|
* proto The protocol. Set to 0 for non-ip packets,
|
|
* or to the protocol read from the packet otherwise.
|
|
* proto != 0 means that we have an IPv4 packet.
|
|
*
|
|
* src_port, dst_port port numbers, in HOST format. Only
|
|
* valid for TCP and UDP packets.
|
|
*
|
|
* src_ip, dst_ip ip addresses, in NETWORK format.
|
|
* Only valid for IPv4 packets.
|
|
*/
|
|
uint8_t proto;
|
|
uint16_t src_port, dst_port; /* NOTE: host format */
|
|
struct in_addr src_ip, dst_ip; /* NOTE: network format */
|
|
int iplen = 0;
|
|
int pktlen;
|
|
|
|
struct ipfw_dyn_info dyn_info;
|
|
struct ip_fw *q = NULL;
|
|
struct ip_fw_chain *chain = &V_layer3_chain;
|
|
|
|
/*
|
|
* We store in ulp a pointer to the upper layer protocol header.
|
|
* In the ipv4 case this is easy to determine from the header,
|
|
* but for ipv6 we might have some additional headers in the middle.
|
|
* ulp is NULL if not found.
|
|
*/
|
|
void *ulp = NULL; /* upper layer protocol pointer. */
|
|
|
|
/* XXX ipv6 variables */
|
|
int is_ipv6 = 0;
|
|
#ifdef INET6
|
|
uint8_t icmp6_type = 0;
|
|
#endif
|
|
uint16_t ext_hd = 0; /* bits vector for extension header filtering */
|
|
/* end of ipv6 variables */
|
|
|
|
int is_ipv4 = 0;
|
|
|
|
int done = 0; /* flag to exit the outer loop */
|
|
IPFW_RLOCK_TRACKER;
|
|
bool mem;
|
|
|
|
if ((mem = (args->flags & IPFW_ARGS_LENMASK))) {
|
|
if (args->flags & IPFW_ARGS_ETHER) {
|
|
eh = (struct ether_header *)args->mem;
|
|
if (eh->ether_type == htons(ETHERTYPE_VLAN))
|
|
ip = (struct ip *)
|
|
((struct ether_vlan_header *)eh + 1);
|
|
else
|
|
ip = (struct ip *)(eh + 1);
|
|
} else {
|
|
eh = NULL;
|
|
ip = (struct ip *)args->mem;
|
|
}
|
|
pktlen = IPFW_ARGS_LENGTH(args->flags);
|
|
args->f_id.fib = args->ifp->if_fib; /* best guess */
|
|
} else {
|
|
m = args->m;
|
|
if (m->m_flags & M_SKIP_FIREWALL || (! V_ipfw_vnet_ready))
|
|
return (IP_FW_PASS); /* accept */
|
|
if (args->flags & IPFW_ARGS_ETHER) {
|
|
/* We need some amount of data to be contiguous. */
|
|
if (m->m_len < min(m->m_pkthdr.len, max_protohdr) &&
|
|
(args->m = m = m_pullup(m, min(m->m_pkthdr.len,
|
|
max_protohdr))) == NULL)
|
|
goto pullup_failed;
|
|
eh = mtod(m, struct ether_header *);
|
|
ip = (struct ip *)(eh + 1);
|
|
} else {
|
|
eh = NULL;
|
|
ip = mtod(m, struct ip *);
|
|
}
|
|
pktlen = m->m_pkthdr.len;
|
|
args->f_id.fib = M_GETFIB(m); /* mbuf not altered */
|
|
}
|
|
|
|
dst_ip.s_addr = 0; /* make sure it is initialized */
|
|
src_ip.s_addr = 0; /* make sure it is initialized */
|
|
src_port = dst_port = 0;
|
|
|
|
DYN_INFO_INIT(&dyn_info);
|
|
/*
|
|
* PULLUP_TO(len, p, T) makes sure that len + sizeof(T) is contiguous,
|
|
* then it sets p to point at the offset "len" in the mbuf. WARNING: the
|
|
* pointer might become stale after other pullups (but we never use it
|
|
* this way).
|
|
*/
|
|
#define PULLUP_TO(_len, p, T) PULLUP_LEN(_len, p, sizeof(T))
|
|
#define EHLEN (eh != NULL ? ((char *)ip - (char *)eh) : 0)
|
|
#define _PULLUP_LOCKED(_len, p, T, unlock) \
|
|
do { \
|
|
int x = (_len) + T + EHLEN; \
|
|
if (mem) { \
|
|
if (__predict_false(pktlen < x)) { \
|
|
unlock; \
|
|
goto pullup_failed; \
|
|
} \
|
|
p = (char *)args->mem + (_len) + EHLEN; \
|
|
} else { \
|
|
if (__predict_false((m)->m_len < x)) { \
|
|
args->m = m = m_pullup(m, x); \
|
|
if (m == NULL) { \
|
|
unlock; \
|
|
goto pullup_failed; \
|
|
} \
|
|
} \
|
|
p = mtod(m, char *) + (_len) + EHLEN; \
|
|
} \
|
|
} while (0)
|
|
|
|
#define PULLUP_LEN(_len, p, T) _PULLUP_LOCKED(_len, p, T, )
|
|
#define PULLUP_LEN_LOCKED(_len, p, T) \
|
|
_PULLUP_LOCKED(_len, p, T, IPFW_PF_RUNLOCK(chain)); \
|
|
UPDATE_POINTERS()
|
|
/*
|
|
* In case pointers got stale after pullups, update them.
|
|
*/
|
|
#define UPDATE_POINTERS() \
|
|
do { \
|
|
if (!mem) { \
|
|
if (eh != NULL) { \
|
|
eh = mtod(m, struct ether_header *); \
|
|
ip = (struct ip *)(eh + 1); \
|
|
} else \
|
|
ip = mtod(m, struct ip *); \
|
|
args->m = m; \
|
|
} \
|
|
} while (0)
|
|
|
|
/* Identify IP packets and fill up variables. */
|
|
if (pktlen >= sizeof(struct ip6_hdr) &&
|
|
(eh == NULL || eh->ether_type == htons(ETHERTYPE_IPV6)) &&
|
|
ip->ip_v == 6) {
|
|
struct ip6_hdr *ip6 = (struct ip6_hdr *)ip;
|
|
|
|
is_ipv6 = 1;
|
|
args->flags |= IPFW_ARGS_IP6;
|
|
hlen = sizeof(struct ip6_hdr);
|
|
proto = ip6->ip6_nxt;
|
|
/* Search extension headers to find upper layer protocols */
|
|
while (ulp == NULL && offset == 0) {
|
|
switch (proto) {
|
|
case IPPROTO_ICMPV6:
|
|
PULLUP_TO(hlen, ulp, struct icmp6_hdr);
|
|
#ifdef INET6
|
|
icmp6_type = ICMP6(ulp)->icmp6_type;
|
|
#endif
|
|
break;
|
|
|
|
case IPPROTO_TCP:
|
|
PULLUP_TO(hlen, ulp, struct tcphdr);
|
|
dst_port = TCP(ulp)->th_dport;
|
|
src_port = TCP(ulp)->th_sport;
|
|
/* save flags for dynamic rules */
|
|
args->f_id._flags = TCP(ulp)->th_flags;
|
|
break;
|
|
|
|
case IPPROTO_SCTP:
|
|
if (pktlen >= hlen + sizeof(struct sctphdr) +
|
|
sizeof(struct sctp_chunkhdr) +
|
|
offsetof(struct sctp_init, a_rwnd))
|
|
PULLUP_LEN(hlen, ulp,
|
|
sizeof(struct sctphdr) +
|
|
sizeof(struct sctp_chunkhdr) +
|
|
offsetof(struct sctp_init, a_rwnd));
|
|
else if (pktlen >= hlen + sizeof(struct sctphdr))
|
|
PULLUP_LEN(hlen, ulp, pktlen - hlen);
|
|
else
|
|
PULLUP_LEN(hlen, ulp,
|
|
sizeof(struct sctphdr));
|
|
src_port = SCTP(ulp)->src_port;
|
|
dst_port = SCTP(ulp)->dest_port;
|
|
break;
|
|
|
|
case IPPROTO_UDP:
|
|
case IPPROTO_UDPLITE:
|
|
PULLUP_TO(hlen, ulp, struct udphdr);
|
|
dst_port = UDP(ulp)->uh_dport;
|
|
src_port = UDP(ulp)->uh_sport;
|
|
break;
|
|
|
|
case IPPROTO_HOPOPTS: /* RFC 2460 */
|
|
PULLUP_TO(hlen, ulp, struct ip6_hbh);
|
|
ext_hd |= EXT_HOPOPTS;
|
|
hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3;
|
|
proto = ((struct ip6_hbh *)ulp)->ip6h_nxt;
|
|
ulp = NULL;
|
|
break;
|
|
|
|
case IPPROTO_ROUTING: /* RFC 2460 */
|
|
PULLUP_TO(hlen, ulp, struct ip6_rthdr);
|
|
switch (((struct ip6_rthdr *)ulp)->ip6r_type) {
|
|
case 0:
|
|
ext_hd |= EXT_RTHDR0;
|
|
break;
|
|
case 2:
|
|
ext_hd |= EXT_RTHDR2;
|
|
break;
|
|
default:
|
|
if (V_fw_verbose)
|
|
printf("IPFW2: IPV6 - Unknown "
|
|
"Routing Header type(%d)\n",
|
|
((struct ip6_rthdr *)
|
|
ulp)->ip6r_type);
|
|
if (V_fw_deny_unknown_exthdrs)
|
|
return (IP_FW_DENY);
|
|
break;
|
|
}
|
|
ext_hd |= EXT_ROUTING;
|
|
hlen += (((struct ip6_rthdr *)ulp)->ip6r_len + 1) << 3;
|
|
proto = ((struct ip6_rthdr *)ulp)->ip6r_nxt;
|
|
ulp = NULL;
|
|
break;
|
|
|
|
case IPPROTO_FRAGMENT: /* RFC 2460 */
|
|
PULLUP_TO(hlen, ulp, struct ip6_frag);
|
|
ext_hd |= EXT_FRAGMENT;
|
|
hlen += sizeof (struct ip6_frag);
|
|
proto = ((struct ip6_frag *)ulp)->ip6f_nxt;
|
|
offset = ((struct ip6_frag *)ulp)->ip6f_offlg &
|
|
IP6F_OFF_MASK;
|
|
ip6f_mf = ((struct ip6_frag *)ulp)->ip6f_offlg &
|
|
IP6F_MORE_FRAG;
|
|
if (V_fw_permit_single_frag6 == 0 &&
|
|
offset == 0 && ip6f_mf == 0) {
|
|
if (V_fw_verbose)
|
|
printf("IPFW2: IPV6 - Invalid "
|
|
"Fragment Header\n");
|
|
if (V_fw_deny_unknown_exthdrs)
|
|
return (IP_FW_DENY);
|
|
break;
|
|
}
|
|
args->f_id.extra =
|
|
ntohl(((struct ip6_frag *)ulp)->ip6f_ident);
|
|
ulp = NULL;
|
|
break;
|
|
|
|
case IPPROTO_DSTOPTS: /* RFC 2460 */
|
|
PULLUP_TO(hlen, ulp, struct ip6_hbh);
|
|
ext_hd |= EXT_DSTOPTS;
|
|
hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3;
|
|
proto = ((struct ip6_hbh *)ulp)->ip6h_nxt;
|
|
ulp = NULL;
|
|
break;
|
|
|
|
case IPPROTO_AH: /* RFC 2402 */
|
|
PULLUP_TO(hlen, ulp, struct ip6_ext);
|
|
ext_hd |= EXT_AH;
|
|
hlen += (((struct ip6_ext *)ulp)->ip6e_len + 2) << 2;
|
|
proto = ((struct ip6_ext *)ulp)->ip6e_nxt;
|
|
ulp = NULL;
|
|
break;
|
|
|
|
case IPPROTO_ESP: /* RFC 2406 */
|
|
PULLUP_TO(hlen, ulp, uint32_t); /* SPI, Seq# */
|
|
/* Anything past Seq# is variable length and
|
|
* data past this ext. header is encrypted. */
|
|
ext_hd |= EXT_ESP;
|
|
break;
|
|
|
|
case IPPROTO_NONE: /* RFC 2460 */
|
|
/*
|
|
* Packet ends here, and IPv6 header has
|
|
* already been pulled up. If ip6e_len!=0
|
|
* then octets must be ignored.
|
|
*/
|
|
ulp = ip; /* non-NULL to get out of loop. */
|
|
break;
|
|
|
|
case IPPROTO_OSPFIGP:
|
|
/* XXX OSPF header check? */
|
|
PULLUP_TO(hlen, ulp, struct ip6_ext);
|
|
break;
|
|
|
|
case IPPROTO_PIM:
|
|
/* XXX PIM header check? */
|
|
PULLUP_TO(hlen, ulp, struct pim);
|
|
break;
|
|
|
|
case IPPROTO_GRE: /* RFC 1701 */
|
|
/* XXX GRE header check? */
|
|
PULLUP_TO(hlen, ulp, struct grehdr);
|
|
break;
|
|
|
|
case IPPROTO_CARP:
|
|
PULLUP_TO(hlen, ulp, offsetof(
|
|
struct carp_header, carp_counter));
|
|
if (CARP_ADVERTISEMENT !=
|
|
((struct carp_header *)ulp)->carp_type)
|
|
return (IP_FW_DENY);
|
|
break;
|
|
|
|
case IPPROTO_IPV6: /* RFC 2893 */
|
|
PULLUP_TO(hlen, ulp, struct ip6_hdr);
|
|
break;
|
|
|
|
case IPPROTO_IPV4: /* RFC 2893 */
|
|
PULLUP_TO(hlen, ulp, struct ip);
|
|
break;
|
|
|
|
default:
|
|
if (V_fw_verbose)
|
|
printf("IPFW2: IPV6 - Unknown "
|
|
"Extension Header(%d), ext_hd=%x\n",
|
|
proto, ext_hd);
|
|
if (V_fw_deny_unknown_exthdrs)
|
|
return (IP_FW_DENY);
|
|
PULLUP_TO(hlen, ulp, struct ip6_ext);
|
|
break;
|
|
} /*switch */
|
|
}
|
|
UPDATE_POINTERS();
|
|
ip6 = (struct ip6_hdr *)ip;
|
|
args->f_id.addr_type = 6;
|
|
args->f_id.src_ip6 = ip6->ip6_src;
|
|
args->f_id.dst_ip6 = ip6->ip6_dst;
|
|
args->f_id.flow_id6 = ntohl(ip6->ip6_flow);
|
|
iplen = ntohs(ip6->ip6_plen) + sizeof(*ip6);
|
|
} else if (pktlen >= sizeof(struct ip) &&
|
|
(eh == NULL || eh->ether_type == htons(ETHERTYPE_IP)) &&
|
|
ip->ip_v == 4) {
|
|
is_ipv4 = 1;
|
|
args->flags |= IPFW_ARGS_IP4;
|
|
hlen = ip->ip_hl << 2;
|
|
/*
|
|
* Collect parameters into local variables for faster
|
|
* matching.
|
|
*/
|
|
proto = ip->ip_p;
|
|
src_ip = ip->ip_src;
|
|
dst_ip = ip->ip_dst;
|
|
offset = ntohs(ip->ip_off) & IP_OFFMASK;
|
|
iplen = ntohs(ip->ip_len);
|
|
|
|
if (offset == 0) {
|
|
switch (proto) {
|
|
case IPPROTO_TCP:
|
|
PULLUP_TO(hlen, ulp, struct tcphdr);
|
|
dst_port = TCP(ulp)->th_dport;
|
|
src_port = TCP(ulp)->th_sport;
|
|
/* save flags for dynamic rules */
|
|
args->f_id._flags = TCP(ulp)->th_flags;
|
|
break;
|
|
|
|
case IPPROTO_SCTP:
|
|
if (pktlen >= hlen + sizeof(struct sctphdr) +
|
|
sizeof(struct sctp_chunkhdr) +
|
|
offsetof(struct sctp_init, a_rwnd))
|
|
PULLUP_LEN(hlen, ulp,
|
|
sizeof(struct sctphdr) +
|
|
sizeof(struct sctp_chunkhdr) +
|
|
offsetof(struct sctp_init, a_rwnd));
|
|
else if (pktlen >= hlen + sizeof(struct sctphdr))
|
|
PULLUP_LEN(hlen, ulp, pktlen - hlen);
|
|
else
|
|
PULLUP_LEN(hlen, ulp,
|
|
sizeof(struct sctphdr));
|
|
src_port = SCTP(ulp)->src_port;
|
|
dst_port = SCTP(ulp)->dest_port;
|
|
break;
|
|
|
|
case IPPROTO_UDP:
|
|
case IPPROTO_UDPLITE:
|
|
PULLUP_TO(hlen, ulp, struct udphdr);
|
|
dst_port = UDP(ulp)->uh_dport;
|
|
src_port = UDP(ulp)->uh_sport;
|
|
break;
|
|
|
|
case IPPROTO_ICMP:
|
|
PULLUP_TO(hlen, ulp, struct icmphdr);
|
|
//args->f_id.flags = ICMP(ulp)->icmp_type;
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
} else {
|
|
if (offset == 1 && proto == IPPROTO_TCP) {
|
|
/* RFC 3128 */
|
|
goto pullup_failed;
|
|
}
|
|
}
|
|
|
|
UPDATE_POINTERS();
|
|
args->f_id.addr_type = 4;
|
|
args->f_id.src_ip = ntohl(src_ip.s_addr);
|
|
args->f_id.dst_ip = ntohl(dst_ip.s_addr);
|
|
} else {
|
|
proto = 0;
|
|
dst_ip.s_addr = src_ip.s_addr = 0;
|
|
|
|
args->f_id.addr_type = 1; /* XXX */
|
|
}
|
|
#undef PULLUP_TO
|
|
pktlen = iplen < pktlen ? iplen: pktlen;
|
|
|
|
/* Properly initialize the rest of f_id */
|
|
args->f_id.proto = proto;
|
|
args->f_id.src_port = src_port = ntohs(src_port);
|
|
args->f_id.dst_port = dst_port = ntohs(dst_port);
|
|
|
|
IPFW_PF_RLOCK(chain);
|
|
if (! V_ipfw_vnet_ready) { /* shutting down, leave NOW. */
|
|
IPFW_PF_RUNLOCK(chain);
|
|
return (IP_FW_PASS); /* accept */
|
|
}
|
|
if (args->flags & IPFW_ARGS_REF) {
|
|
/*
|
|
* Packet has already been tagged as a result of a previous
|
|
* match on rule args->rule aka args->rule_id (PIPE, QUEUE,
|
|
* REASS, NETGRAPH, DIVERT/TEE...)
|
|
* Validate the slot and continue from the next one
|
|
* if still present, otherwise do a lookup.
|
|
*/
|
|
f_pos = (args->rule.chain_id == chain->id) ?
|
|
args->rule.slot :
|
|
ipfw_find_rule(chain, args->rule.rulenum,
|
|
args->rule.rule_id);
|
|
} else {
|
|
f_pos = 0;
|
|
}
|
|
|
|
if (args->flags & IPFW_ARGS_IN) {
|
|
iif = args->ifp;
|
|
oif = NULL;
|
|
} else {
|
|
MPASS(args->flags & IPFW_ARGS_OUT);
|
|
iif = mem ? NULL : m_rcvif(m);
|
|
oif = args->ifp;
|
|
}
|
|
|
|
/*
|
|
* Now scan the rules, and parse microinstructions for each rule.
|
|
* We have two nested loops and an inner switch. Sometimes we
|
|
* need to break out of one or both loops, or re-enter one of
|
|
* the loops with updated variables. Loop variables are:
|
|
*
|
|
* f_pos (outer loop) points to the current rule.
|
|
* On output it points to the matching rule.
|
|
* done (outer loop) is used as a flag to break the loop.
|
|
* l (inner loop) residual length of current rule.
|
|
* cmd points to the current microinstruction.
|
|
*
|
|
* We break the inner loop by setting l=0 and possibly
|
|
* cmdlen=0 if we don't want to advance cmd.
|
|
* We break the outer loop by setting done=1
|
|
* We can restart the inner loop by setting l>0 and f_pos, f, cmd
|
|
* as needed.
|
|
*/
|
|
for (; f_pos < chain->n_rules; f_pos++) {
|
|
ipfw_insn *cmd;
|
|
uint32_t tablearg = 0;
|
|
int l, cmdlen, skip_or; /* skip rest of OR block */
|
|
struct ip_fw *f;
|
|
|
|
f = chain->map[f_pos];
|
|
if (V_set_disable & (1 << f->set) )
|
|
continue;
|
|
|
|
skip_or = 0;
|
|
for (l = f->cmd_len, cmd = f->cmd ; l > 0 ;
|
|
l -= cmdlen, cmd += cmdlen) {
|
|
int match;
|
|
|
|
/*
|
|
* check_body is a jump target used when we find a
|
|
* CHECK_STATE, and need to jump to the body of
|
|
* the target rule.
|
|
*/
|
|
|
|
/* check_body: */
|
|
cmdlen = F_LEN(cmd);
|
|
/*
|
|
* An OR block (insn_1 || .. || insn_n) has the
|
|
* F_OR bit set in all but the last instruction.
|
|
* The first match will set "skip_or", and cause
|
|
* the following instructions to be skipped until
|
|
* past the one with the F_OR bit clear.
|
|
*/
|
|
if (skip_or) { /* skip this instruction */
|
|
if ((cmd->len & F_OR) == 0)
|
|
skip_or = 0; /* next one is good */
|
|
continue;
|
|
}
|
|
match = 0; /* set to 1 if we succeed */
|
|
|
|
switch (cmd->opcode) {
|
|
/*
|
|
* The first set of opcodes compares the packet's
|
|
* fields with some pattern, setting 'match' if a
|
|
* match is found. At the end of the loop there is
|
|
* logic to deal with F_NOT and F_OR flags associated
|
|
* with the opcode.
|
|
*/
|
|
case O_NOP:
|
|
match = 1;
|
|
break;
|
|
|
|
case O_FORWARD_MAC:
|
|
printf("ipfw: opcode %d unimplemented\n",
|
|
cmd->opcode);
|
|
break;
|
|
|
|
case O_GID:
|
|
case O_UID:
|
|
case O_JAIL:
|
|
/*
|
|
* We only check offset == 0 && proto != 0,
|
|
* as this ensures that we have a
|
|
* packet with the ports info.
|
|
*/
|
|
if (offset != 0)
|
|
break;
|
|
if (proto == IPPROTO_TCP ||
|
|
proto == IPPROTO_UDP ||
|
|
proto == IPPROTO_UDPLITE)
|
|
match = check_uidgid(
|
|
(ipfw_insn_u32 *)cmd,
|
|
args, &ucred_lookup,
|
|
#ifdef __FreeBSD__
|
|
&ucred_cache);
|
|
#else
|
|
(void *)&ucred_cache);
|
|
#endif
|
|
break;
|
|
|
|
case O_RECV:
|
|
match = iface_match(iif, (ipfw_insn_if *)cmd,
|
|
chain, &tablearg);
|
|
break;
|
|
|
|
case O_XMIT:
|
|
match = iface_match(oif, (ipfw_insn_if *)cmd,
|
|
chain, &tablearg);
|
|
break;
|
|
|
|
case O_VIA:
|
|
match = iface_match(args->ifp,
|
|
(ipfw_insn_if *)cmd, chain, &tablearg);
|
|
break;
|
|
|
|
case O_MACADDR2:
|
|
if (args->flags & IPFW_ARGS_ETHER) {
|
|
u_int32_t *want = (u_int32_t *)
|
|
((ipfw_insn_mac *)cmd)->addr;
|
|
u_int32_t *mask = (u_int32_t *)
|
|
((ipfw_insn_mac *)cmd)->mask;
|
|
u_int32_t *hdr = (u_int32_t *)eh;
|
|
|
|
match =
|
|
( want[0] == (hdr[0] & mask[0]) &&
|
|
want[1] == (hdr[1] & mask[1]) &&
|
|
want[2] == (hdr[2] & mask[2]) );
|
|
}
|
|
break;
|
|
|
|
case O_MAC_TYPE:
|
|
if (args->flags & IPFW_ARGS_ETHER) {
|
|
u_int16_t *p =
|
|
((ipfw_insn_u16 *)cmd)->ports;
|
|
int i;
|
|
|
|
for (i = cmdlen - 1; !match && i>0;
|
|
i--, p += 2)
|
|
match =
|
|
(ntohs(eh->ether_type) >=
|
|
p[0] &&
|
|
ntohs(eh->ether_type) <=
|
|
p[1]);
|
|
}
|
|
break;
|
|
|
|
case O_FRAG:
|
|
if (is_ipv4) {
|
|
/*
|
|
* Since flags_match() works with
|
|
* uint8_t we pack ip_off into 8 bits.
|
|
* For this match offset is a boolean.
|
|
*/
|
|
match = flags_match(cmd,
|
|
((ntohs(ip->ip_off) & ~IP_OFFMASK)
|
|
>> 8) | (offset != 0));
|
|
} else {
|
|
/*
|
|
* Compatibility: historically bare
|
|
* "frag" would match IPv6 fragments.
|
|
*/
|
|
match = (cmd->arg1 == 0x1 &&
|
|
(offset != 0));
|
|
}
|
|
break;
|
|
|
|
case O_IN: /* "out" is "not in" */
|
|
match = (oif == NULL);
|
|
break;
|
|
|
|
case O_LAYER2:
|
|
match = (args->flags & IPFW_ARGS_ETHER);
|
|
break;
|
|
|
|
case O_DIVERTED:
|
|
if ((args->flags & IPFW_ARGS_REF) == 0)
|
|
break;
|
|
/*
|
|
* For diverted packets, args->rule.info
|
|
* contains the divert port (in host format)
|
|
* reason and direction.
|
|
*/
|
|
match = ((args->rule.info & IPFW_IS_MASK) ==
|
|
IPFW_IS_DIVERT) && (
|
|
((args->rule.info & IPFW_INFO_IN) ?
|
|
1: 2) & cmd->arg1);
|
|
break;
|
|
|
|
case O_PROTO:
|
|
/*
|
|
* We do not allow an arg of 0 so the
|
|
* check of "proto" only suffices.
|
|
*/
|
|
match = (proto == cmd->arg1);
|
|
break;
|
|
|
|
case O_IP_SRC:
|
|
match = is_ipv4 &&
|
|
(((ipfw_insn_ip *)cmd)->addr.s_addr ==
|
|
src_ip.s_addr);
|
|
break;
|
|
|
|
case O_IP_DST_LOOKUP:
|
|
{
|
|
if (cmdlen > F_INSN_SIZE(ipfw_insn_u32)) {
|
|
void *pkey;
|
|
uint32_t vidx, key;
|
|
uint16_t keylen = 0; /* zero if can't match the packet */
|
|
|
|
/* Determine lookup key type */
|
|
vidx = ((ipfw_insn_u32 *)cmd)->d[1];
|
|
switch (vidx) {
|
|
case LOOKUP_DST_IP:
|
|
case LOOKUP_SRC_IP:
|
|
/* Need IP frame */
|
|
if (is_ipv6 == 0 && is_ipv4 == 0)
|
|
break;
|
|
if (vidx == LOOKUP_DST_IP)
|
|
pkey = is_ipv6 ?
|
|
(void *)&args->f_id.dst_ip6:
|
|
(void *)&dst_ip;
|
|
else
|
|
pkey = is_ipv6 ?
|
|
(void *)&args->f_id.src_ip6:
|
|
(void *)&src_ip;
|
|
keylen = is_ipv6 ?
|
|
sizeof(struct in6_addr):
|
|
sizeof(in_addr_t);
|
|
break;
|
|
case LOOKUP_DST_PORT:
|
|
case LOOKUP_SRC_PORT:
|
|
/* Need IP frame */
|
|
if (is_ipv6 == 0 && is_ipv4 == 0)
|
|
break;
|
|
/* Skip fragments */
|
|
if (offset != 0)
|
|
break;
|
|
/* Skip proto without ports */
|
|
if (proto != IPPROTO_TCP &&
|
|
proto != IPPROTO_UDP &&
|
|
proto != IPPROTO_UDPLITE &&
|
|
proto != IPPROTO_SCTP)
|
|
break;
|
|
key = vidx == LOOKUP_DST_PORT ?
|
|
dst_port:
|
|
src_port;
|
|
pkey = &key;
|
|
keylen = sizeof(key);
|
|
break;
|
|
case LOOKUP_UID:
|
|
case LOOKUP_JAIL:
|
|
check_uidgid(
|
|
(ipfw_insn_u32 *)cmd,
|
|
args, &ucred_lookup,
|
|
&ucred_cache);
|
|
key = vidx == LOOKUP_UID ?
|
|
ucred_cache->cr_uid:
|
|
ucred_cache->cr_prison->pr_id;
|
|
pkey = &key;
|
|
keylen = sizeof(key);
|
|
break;
|
|
case LOOKUP_DSCP:
|
|
/* Need IP frame */
|
|
if (is_ipv6 == 0 && is_ipv4 == 0)
|
|
break;
|
|
if (is_ipv6)
|
|
key = IPV6_DSCP(
|
|
(struct ip6_hdr *)ip) >> 2;
|
|
else
|
|
key = ip->ip_tos >> 2;
|
|
pkey = &key;
|
|
keylen = sizeof(key);
|
|
break;
|
|
case LOOKUP_DST_MAC:
|
|
case LOOKUP_SRC_MAC:
|
|
/* Need ether frame */
|
|
if ((args->flags & IPFW_ARGS_ETHER) == 0)
|
|
break;
|
|
pkey = vidx == LOOKUP_DST_MAC ?
|
|
eh->ether_dhost:
|
|
eh->ether_shost;
|
|
keylen = ETHER_ADDR_LEN;
|
|
break;
|
|
case LOOKUP_MARK:
|
|
key = args->rule.pkt_mark;
|
|
pkey = &key;
|
|
keylen = sizeof(key);
|
|
break;
|
|
}
|
|
if (keylen == 0)
|
|
break;
|
|
match = ipfw_lookup_table(chain,
|
|
cmd->arg1, keylen, pkey, &vidx);
|
|
if (!match)
|
|
break;
|
|
tablearg = vidx;
|
|
break;
|
|
}
|
|
/* cmdlen =< F_INSN_SIZE(ipfw_insn_u32) */
|
|
/* FALLTHROUGH */
|
|
}
|
|
case O_IP_SRC_LOOKUP:
|
|
{
|
|
void *pkey;
|
|
uint32_t vidx;
|
|
uint16_t keylen;
|
|
|
|
if (is_ipv4) {
|
|
keylen = sizeof(in_addr_t);
|
|
if (cmd->opcode == O_IP_DST_LOOKUP)
|
|
pkey = &dst_ip;
|
|
else
|
|
pkey = &src_ip;
|
|
} else if (is_ipv6) {
|
|
keylen = sizeof(struct in6_addr);
|
|
if (cmd->opcode == O_IP_DST_LOOKUP)
|
|
pkey = &args->f_id.dst_ip6;
|
|
else
|
|
pkey = &args->f_id.src_ip6;
|
|
} else
|
|
break;
|
|
match = ipfw_lookup_table(chain, cmd->arg1,
|
|
keylen, pkey, &vidx);
|
|
if (!match)
|
|
break;
|
|
if (cmdlen == F_INSN_SIZE(ipfw_insn_u32)) {
|
|
match = ((ipfw_insn_u32 *)cmd)->d[0] ==
|
|
TARG_VAL(chain, vidx, tag);
|
|
if (!match)
|
|
break;
|
|
}
|
|
tablearg = vidx;
|
|
break;
|
|
}
|
|
|
|
case O_MAC_SRC_LOOKUP:
|
|
case O_MAC_DST_LOOKUP:
|
|
{
|
|
void *pkey;
|
|
uint32_t vidx;
|
|
uint16_t keylen = ETHER_ADDR_LEN;
|
|
|
|
/* Need ether frame */
|
|
if ((args->flags & IPFW_ARGS_ETHER) == 0)
|
|
break;
|
|
|
|
if (cmd->opcode == O_MAC_DST_LOOKUP)
|
|
pkey = eh->ether_dhost;
|
|
else
|
|
pkey = eh->ether_shost;
|
|
|
|
match = ipfw_lookup_table(chain, cmd->arg1,
|
|
keylen, pkey, &vidx);
|
|
if (!match)
|
|
break;
|
|
if (cmdlen == F_INSN_SIZE(ipfw_insn_u32)) {
|
|
match = ((ipfw_insn_u32 *)cmd)->d[0] ==
|
|
TARG_VAL(chain, vidx, tag);
|
|
if (!match)
|
|
break;
|
|
}
|
|
tablearg = vidx;
|
|
break;
|
|
}
|
|
|
|
case O_IP_FLOW_LOOKUP:
|
|
{
|
|
uint32_t v = 0;
|
|
match = ipfw_lookup_table(chain,
|
|
cmd->arg1, 0, &args->f_id, &v);
|
|
if (!match)
|
|
break;
|
|
if (cmdlen == F_INSN_SIZE(ipfw_insn_u32))
|
|
match = ((ipfw_insn_u32 *)cmd)->d[0] ==
|
|
TARG_VAL(chain, v, tag);
|
|
if (match)
|
|
tablearg = v;
|
|
}
|
|
break;
|
|
case O_IP_SRC_MASK:
|
|
case O_IP_DST_MASK:
|
|
if (is_ipv4) {
|
|
uint32_t a =
|
|
(cmd->opcode == O_IP_DST_MASK) ?
|
|
dst_ip.s_addr : src_ip.s_addr;
|
|
uint32_t *p = ((ipfw_insn_u32 *)cmd)->d;
|
|
int i = cmdlen-1;
|
|
|
|
for (; !match && i>0; i-= 2, p+= 2)
|
|
match = (p[0] == (a & p[1]));
|
|
}
|
|
break;
|
|
|
|
case O_IP_SRC_ME:
|
|
if (is_ipv4) {
|
|
match = in_localip(src_ip);
|
|
break;
|
|
}
|
|
#ifdef INET6
|
|
/* FALLTHROUGH */
|
|
case O_IP6_SRC_ME:
|
|
match = is_ipv6 &&
|
|
ipfw_localip6(&args->f_id.src_ip6);
|
|
#endif
|
|
break;
|
|
|
|
case O_IP_DST_SET:
|
|
case O_IP_SRC_SET:
|
|
if (is_ipv4) {
|
|
u_int32_t *d = (u_int32_t *)(cmd+1);
|
|
u_int32_t addr =
|
|
cmd->opcode == O_IP_DST_SET ?
|
|
args->f_id.dst_ip :
|
|
args->f_id.src_ip;
|
|
|
|
if (addr < d[0])
|
|
break;
|
|
addr -= d[0]; /* subtract base */
|
|
match = (addr < cmd->arg1) &&
|
|
( d[ 1 + (addr>>5)] &
|
|
(1<<(addr & 0x1f)) );
|
|
}
|
|
break;
|
|
|
|
case O_IP_DST:
|
|
match = is_ipv4 &&
|
|
(((ipfw_insn_ip *)cmd)->addr.s_addr ==
|
|
dst_ip.s_addr);
|
|
break;
|
|
|
|
case O_IP_DST_ME:
|
|
if (is_ipv4) {
|
|
match = in_localip(dst_ip);
|
|
break;
|
|
}
|
|
#ifdef INET6
|
|
/* FALLTHROUGH */
|
|
case O_IP6_DST_ME:
|
|
match = is_ipv6 &&
|
|
ipfw_localip6(&args->f_id.dst_ip6);
|
|
#endif
|
|
break;
|
|
|
|
case O_IP_SRCPORT:
|
|
case O_IP_DSTPORT:
|
|
/*
|
|
* offset == 0 && proto != 0 is enough
|
|
* to guarantee that we have a
|
|
* packet with port info.
|
|
*/
|
|
if ((proto == IPPROTO_UDP ||
|
|
proto == IPPROTO_UDPLITE ||
|
|
proto == IPPROTO_TCP ||
|
|
proto == IPPROTO_SCTP) && offset == 0) {
|
|
u_int16_t x =
|
|
(cmd->opcode == O_IP_SRCPORT) ?
|
|
src_port : dst_port ;
|
|
u_int16_t *p =
|
|
((ipfw_insn_u16 *)cmd)->ports;
|
|
int i;
|
|
|
|
for (i = cmdlen - 1; !match && i>0;
|
|
i--, p += 2)
|
|
match = (x>=p[0] && x<=p[1]);
|
|
}
|
|
break;
|
|
|
|
case O_ICMPTYPE:
|
|
match = (offset == 0 && proto==IPPROTO_ICMP &&
|
|
icmptype_match(ICMP(ulp), (ipfw_insn_u32 *)cmd) );
|
|
break;
|
|
|
|
#ifdef INET6
|
|
case O_ICMP6TYPE:
|
|
match = is_ipv6 && offset == 0 &&
|
|
proto==IPPROTO_ICMPV6 &&
|
|
icmp6type_match(
|
|
ICMP6(ulp)->icmp6_type,
|
|
(ipfw_insn_u32 *)cmd);
|
|
break;
|
|
#endif /* INET6 */
|
|
|
|
case O_IPOPT:
|
|
match = (is_ipv4 &&
|
|
ipopts_match(ip, cmd) );
|
|
break;
|
|
|
|
case O_IPVER:
|
|
match = ((is_ipv4 || is_ipv6) &&
|
|
cmd->arg1 == ip->ip_v);
|
|
break;
|
|
|
|
case O_IPID:
|
|
case O_IPTTL:
|
|
if (!is_ipv4)
|
|
break;
|
|
case O_IPLEN:
|
|
{ /* only for IP packets */
|
|
uint16_t x;
|
|
uint16_t *p;
|
|
int i;
|
|
|
|
if (cmd->opcode == O_IPLEN)
|
|
x = iplen;
|
|
else if (cmd->opcode == O_IPTTL)
|
|
x = ip->ip_ttl;
|
|
else /* must be IPID */
|
|
x = ntohs(ip->ip_id);
|
|
if (cmdlen == 1) {
|
|
match = (cmd->arg1 == x);
|
|
break;
|
|
}
|
|
/* otherwise we have ranges */
|
|
p = ((ipfw_insn_u16 *)cmd)->ports;
|
|
i = cmdlen - 1;
|
|
for (; !match && i>0; i--, p += 2)
|
|
match = (x >= p[0] && x <= p[1]);
|
|
}
|
|
break;
|
|
|
|
case O_IPPRECEDENCE:
|
|
match = (is_ipv4 &&
|
|
(cmd->arg1 == (ip->ip_tos & 0xe0)) );
|
|
break;
|
|
|
|
case O_IPTOS:
|
|
match = (is_ipv4 &&
|
|
flags_match(cmd, ip->ip_tos));
|
|
break;
|
|
|
|
case O_DSCP:
|
|
{
|
|
uint32_t *p;
|
|
uint16_t x;
|
|
|
|
p = ((ipfw_insn_u32 *)cmd)->d;
|
|
|
|
if (is_ipv4)
|
|
x = ip->ip_tos >> 2;
|
|
else if (is_ipv6) {
|
|
x = IPV6_DSCP(
|
|
(struct ip6_hdr *)ip) >> 2;
|
|
x &= 0x3f;
|
|
} else
|
|
break;
|
|
|
|
/* DSCP bitmask is stored as low_u32 high_u32 */
|
|
if (x >= 32)
|
|
match = *(p + 1) & (1 << (x - 32));
|
|
else
|
|
match = *p & (1 << x);
|
|
}
|
|
break;
|
|
|
|
case O_TCPDATALEN:
|
|
if (proto == IPPROTO_TCP && offset == 0) {
|
|
struct tcphdr *tcp;
|
|
uint16_t x;
|
|
uint16_t *p;
|
|
int i;
|
|
#ifdef INET6
|
|
if (is_ipv6) {
|
|
struct ip6_hdr *ip6;
|
|
|
|
ip6 = (struct ip6_hdr *)ip;
|
|
if (ip6->ip6_plen == 0) {
|
|
/*
|
|
* Jumbo payload is not
|
|
* supported by this
|
|
* opcode.
|
|
*/
|
|
break;
|
|
}
|
|
x = iplen - hlen;
|
|
} else
|
|
#endif /* INET6 */
|
|
x = iplen - (ip->ip_hl << 2);
|
|
tcp = TCP(ulp);
|
|
x -= tcp->th_off << 2;
|
|
if (cmdlen == 1) {
|
|
match = (cmd->arg1 == x);
|
|
break;
|
|
}
|
|
/* otherwise we have ranges */
|
|
p = ((ipfw_insn_u16 *)cmd)->ports;
|
|
i = cmdlen - 1;
|
|
for (; !match && i>0; i--, p += 2)
|
|
match = (x >= p[0] && x <= p[1]);
|
|
}
|
|
break;
|
|
|
|
case O_TCPFLAGS:
|
|
match = (proto == IPPROTO_TCP && offset == 0 &&
|
|
flags_match(cmd, TCP(ulp)->th_flags));
|
|
break;
|
|
|
|
case O_TCPOPTS:
|
|
if (proto == IPPROTO_TCP && offset == 0 && ulp){
|
|
PULLUP_LEN_LOCKED(hlen, ulp,
|
|
(TCP(ulp)->th_off << 2));
|
|
match = tcpopts_match(TCP(ulp), cmd);
|
|
}
|
|
break;
|
|
|
|
case O_TCPSEQ:
|
|
match = (proto == IPPROTO_TCP && offset == 0 &&
|
|
((ipfw_insn_u32 *)cmd)->d[0] ==
|
|
TCP(ulp)->th_seq);
|
|
break;
|
|
|
|
case O_TCPACK:
|
|
match = (proto == IPPROTO_TCP && offset == 0 &&
|
|
((ipfw_insn_u32 *)cmd)->d[0] ==
|
|
TCP(ulp)->th_ack);
|
|
break;
|
|
|
|
case O_TCPMSS:
|
|
if (proto == IPPROTO_TCP &&
|
|
(args->f_id._flags & TH_SYN) != 0 &&
|
|
ulp != NULL) {
|
|
uint16_t mss, *p;
|
|
int i;
|
|
|
|
PULLUP_LEN_LOCKED(hlen, ulp,
|
|
(TCP(ulp)->th_off << 2));
|
|
if ((tcpopts_parse(TCP(ulp), &mss) &
|
|
IP_FW_TCPOPT_MSS) == 0)
|
|
break;
|
|
if (cmdlen == 1) {
|
|
match = (cmd->arg1 == mss);
|
|
break;
|
|
}
|
|
/* Otherwise we have ranges. */
|
|
p = ((ipfw_insn_u16 *)cmd)->ports;
|
|
i = cmdlen - 1;
|
|
for (; !match && i > 0; i--, p += 2)
|
|
match = (mss >= p[0] &&
|
|
mss <= p[1]);
|
|
}
|
|
break;
|
|
|
|
case O_TCPWIN:
|
|
if (proto == IPPROTO_TCP && offset == 0) {
|
|
uint16_t x;
|
|
uint16_t *p;
|
|
int i;
|
|
|
|
x = ntohs(TCP(ulp)->th_win);
|
|
if (cmdlen == 1) {
|
|
match = (cmd->arg1 == x);
|
|
break;
|
|
}
|
|
/* Otherwise we have ranges. */
|
|
p = ((ipfw_insn_u16 *)cmd)->ports;
|
|
i = cmdlen - 1;
|
|
for (; !match && i > 0; i--, p += 2)
|
|
match = (x >= p[0] && x <= p[1]);
|
|
}
|
|
break;
|
|
|
|
case O_ESTAB:
|
|
/* reject packets which have SYN only */
|
|
/* XXX should i also check for TH_ACK ? */
|
|
match = (proto == IPPROTO_TCP && offset == 0 &&
|
|
(TCP(ulp)->th_flags &
|
|
(TH_RST | TH_ACK | TH_SYN)) != TH_SYN);
|
|
break;
|
|
|
|
case O_ALTQ: {
|
|
struct pf_mtag *at;
|
|
struct m_tag *mtag;
|
|
ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
|
|
|
|
/*
|
|
* ALTQ uses mbuf tags from another
|
|
* packet filtering system - pf(4).
|
|
* We allocate a tag in its format
|
|
* and fill it in, pretending to be pf(4).
|
|
*/
|
|
match = 1;
|
|
at = pf_find_mtag(m);
|
|
if (at != NULL && at->qid != 0)
|
|
break;
|
|
mtag = m_tag_get(PACKET_TAG_PF,
|
|
sizeof(struct pf_mtag), M_NOWAIT | M_ZERO);
|
|
if (mtag == NULL) {
|
|
/*
|
|
* Let the packet fall back to the
|
|
* default ALTQ.
|
|
*/
|
|
break;
|
|
}
|
|
m_tag_prepend(m, mtag);
|
|
at = (struct pf_mtag *)(mtag + 1);
|
|
at->qid = altq->qid;
|
|
at->hdr = ip;
|
|
break;
|
|
}
|
|
|
|
case O_LOG:
|
|
ipfw_log(chain, f, hlen, args,
|
|
offset | ip6f_mf, tablearg, ip);
|
|
match = 1;
|
|
break;
|
|
|
|
case O_PROB:
|
|
match = (random()<((ipfw_insn_u32 *)cmd)->d[0]);
|
|
break;
|
|
|
|
case O_VERREVPATH:
|
|
/* Outgoing packets automatically pass/match */
|
|
match = (args->flags & IPFW_ARGS_OUT ||
|
|
(
|
|
#ifdef INET6
|
|
is_ipv6 ?
|
|
verify_path6(&(args->f_id.src_ip6),
|
|
iif, args->f_id.fib) :
|
|
#endif
|
|
verify_path(src_ip, iif, args->f_id.fib)));
|
|
break;
|
|
|
|
case O_VERSRCREACH:
|
|
/* Outgoing packets automatically pass/match */
|
|
match = (hlen > 0 && ((oif != NULL) || (
|
|
#ifdef INET6
|
|
is_ipv6 ?
|
|
verify_path6(&(args->f_id.src_ip6),
|
|
NULL, args->f_id.fib) :
|
|
#endif
|
|
verify_path(src_ip, NULL, args->f_id.fib))));
|
|
break;
|
|
|
|
case O_ANTISPOOF:
|
|
/* Outgoing packets automatically pass/match */
|
|
if (oif == NULL && hlen > 0 &&
|
|
( (is_ipv4 && in_localaddr(src_ip))
|
|
#ifdef INET6
|
|
|| (is_ipv6 &&
|
|
in6_localaddr(&(args->f_id.src_ip6)))
|
|
#endif
|
|
))
|
|
match =
|
|
#ifdef INET6
|
|
is_ipv6 ? verify_path6(
|
|
&(args->f_id.src_ip6), iif,
|
|
args->f_id.fib) :
|
|
#endif
|
|
verify_path(src_ip, iif,
|
|
args->f_id.fib);
|
|
else
|
|
match = 1;
|
|
break;
|
|
|
|
case O_IPSEC:
|
|
match = (m_tag_find(m,
|
|
PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL);
|
|
/* otherwise no match */
|
|
break;
|
|
|
|
#ifdef INET6
|
|
case O_IP6_SRC:
|
|
match = is_ipv6 &&
|
|
IN6_ARE_ADDR_EQUAL(&args->f_id.src_ip6,
|
|
&((ipfw_insn_ip6 *)cmd)->addr6);
|
|
break;
|
|
|
|
case O_IP6_DST:
|
|
match = is_ipv6 &&
|
|
IN6_ARE_ADDR_EQUAL(&args->f_id.dst_ip6,
|
|
&((ipfw_insn_ip6 *)cmd)->addr6);
|
|
break;
|
|
case O_IP6_SRC_MASK:
|
|
case O_IP6_DST_MASK:
|
|
if (is_ipv6) {
|
|
int i = cmdlen - 1;
|
|
struct in6_addr p;
|
|
struct in6_addr *d =
|
|
&((ipfw_insn_ip6 *)cmd)->addr6;
|
|
|
|
for (; !match && i > 0; d += 2,
|
|
i -= F_INSN_SIZE(struct in6_addr)
|
|
* 2) {
|
|
p = (cmd->opcode ==
|
|
O_IP6_SRC_MASK) ?
|
|
args->f_id.src_ip6:
|
|
args->f_id.dst_ip6;
|
|
APPLY_MASK(&p, &d[1]);
|
|
match =
|
|
IN6_ARE_ADDR_EQUAL(&d[0],
|
|
&p);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case O_FLOW6ID:
|
|
match = is_ipv6 &&
|
|
flow6id_match(args->f_id.flow_id6,
|
|
(ipfw_insn_u32 *) cmd);
|
|
break;
|
|
|
|
case O_EXT_HDR:
|
|
match = is_ipv6 &&
|
|
(ext_hd & ((ipfw_insn *) cmd)->arg1);
|
|
break;
|
|
|
|
case O_IP6:
|
|
match = is_ipv6;
|
|
break;
|
|
#endif
|
|
|
|
case O_IP4:
|
|
match = is_ipv4;
|
|
break;
|
|
|
|
case O_TAG: {
|
|
struct m_tag *mtag;
|
|
uint32_t tag = TARG(cmd->arg1, tag);
|
|
|
|
/* Packet is already tagged with this tag? */
|
|
mtag = m_tag_locate(m, MTAG_IPFW, tag, NULL);
|
|
|
|
/* We have `untag' action when F_NOT flag is
|
|
* present. And we must remove this mtag from
|
|
* mbuf and reset `match' to zero (`match' will
|
|
* be inversed later).
|
|
* Otherwise we should allocate new mtag and
|
|
* push it into mbuf.
|
|
*/
|
|
if (cmd->len & F_NOT) { /* `untag' action */
|
|
if (mtag != NULL)
|
|
m_tag_delete(m, mtag);
|
|
match = 0;
|
|
} else {
|
|
if (mtag == NULL) {
|
|
mtag = m_tag_alloc( MTAG_IPFW,
|
|
tag, 0, M_NOWAIT);
|
|
if (mtag != NULL)
|
|
m_tag_prepend(m, mtag);
|
|
}
|
|
match = 1;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case O_FIB: /* try match the specified fib */
|
|
if (args->f_id.fib == cmd->arg1)
|
|
match = 1;
|
|
break;
|
|
|
|
case O_SOCKARG: {
|
|
#ifndef USERSPACE /* not supported in userspace */
|
|
struct inpcb *inp = args->inp;
|
|
struct inpcbinfo *pi;
|
|
bool inp_locked = false;
|
|
|
|
if (proto == IPPROTO_TCP)
|
|
pi = &V_tcbinfo;
|
|
else if (proto == IPPROTO_UDP)
|
|
pi = &V_udbinfo;
|
|
else if (proto == IPPROTO_UDPLITE)
|
|
pi = &V_ulitecbinfo;
|
|
else
|
|
break;
|
|
|
|
/*
|
|
* XXXRW: so_user_cookie should almost
|
|
* certainly be inp_user_cookie?
|
|
*/
|
|
|
|
/*
|
|
* For incoming packet lookup the inpcb
|
|
* using the src/dest ip/port tuple.
|
|
*/
|
|
if (is_ipv4 && inp == NULL) {
|
|
inp = in_pcblookup(pi,
|
|
src_ip, htons(src_port),
|
|
dst_ip, htons(dst_port),
|
|
INPLOOKUP_RLOCKPCB, NULL);
|
|
inp_locked = true;
|
|
}
|
|
#ifdef INET6
|
|
if (is_ipv6 && inp == NULL) {
|
|
inp = in6_pcblookup(pi,
|
|
&args->f_id.src_ip6,
|
|
htons(src_port),
|
|
&args->f_id.dst_ip6,
|
|
htons(dst_port),
|
|
INPLOOKUP_RLOCKPCB, NULL);
|
|
inp_locked = true;
|
|
}
|
|
#endif /* INET6 */
|
|
if (inp != NULL) {
|
|
if (inp->inp_socket) {
|
|
tablearg =
|
|
inp->inp_socket->so_user_cookie;
|
|
if (tablearg)
|
|
match = 1;
|
|
}
|
|
if (inp_locked)
|
|
INP_RUNLOCK(inp);
|
|
}
|
|
#endif /* !USERSPACE */
|
|
break;
|
|
}
|
|
|
|
case O_TAGGED: {
|
|
struct m_tag *mtag;
|
|
uint32_t tag = TARG(cmd->arg1, tag);
|
|
|
|
if (cmdlen == 1) {
|
|
match = m_tag_locate(m, MTAG_IPFW,
|
|
tag, NULL) != NULL;
|
|
break;
|
|
}
|
|
|
|
/* we have ranges */
|
|
for (mtag = m_tag_first(m);
|
|
mtag != NULL && !match;
|
|
mtag = m_tag_next(m, mtag)) {
|
|
uint16_t *p;
|
|
int i;
|
|
|
|
if (mtag->m_tag_cookie != MTAG_IPFW)
|
|
continue;
|
|
|
|
p = ((ipfw_insn_u16 *)cmd)->ports;
|
|
i = cmdlen - 1;
|
|
for(; !match && i > 0; i--, p += 2)
|
|
match =
|
|
mtag->m_tag_id >= p[0] &&
|
|
mtag->m_tag_id <= p[1];
|
|
}
|
|
break;
|
|
}
|
|
|
|
case O_MARK: {
|
|
uint32_t mark;
|
|
if (cmd->arg1 == IP_FW_TARG)
|
|
mark = TARG_VAL(chain, tablearg, mark);
|
|
else
|
|
mark = ((ipfw_insn_u32 *)cmd)->d[0];
|
|
match =
|
|
(args->rule.pkt_mark &
|
|
((ipfw_insn_u32 *)cmd)->d[1]) ==
|
|
(mark & ((ipfw_insn_u32 *)cmd)->d[1]);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* The second set of opcodes represents 'actions',
|
|
* i.e. the terminal part of a rule once the packet
|
|
* matches all previous patterns.
|
|
* Typically there is only one action for each rule,
|
|
* and the opcode is stored at the end of the rule
|
|
* (but there are exceptions -- see below).
|
|
*
|
|
* In general, here we set retval and terminate the
|
|
* outer loop (would be a 'break 3' in some language,
|
|
* but we need to set l=0, done=1)
|
|
*
|
|
* Exceptions:
|
|
* O_COUNT and O_SKIPTO actions:
|
|
* instead of terminating, we jump to the next rule
|
|
* (setting l=0), or to the SKIPTO target (setting
|
|
* f/f_len, cmd and l as needed), respectively.
|
|
*
|
|
* O_TAG, O_LOG and O_ALTQ action parameters:
|
|
* perform some action and set match = 1;
|
|
*
|
|
* O_LIMIT and O_KEEP_STATE: these opcodes are
|
|
* not real 'actions', and are stored right
|
|
* before the 'action' part of the rule (one
|
|
* exception is O_SKIP_ACTION which could be
|
|
* between these opcodes and 'action' one).
|
|
* These opcodes try to install an entry in the
|
|
* state tables; if successful, we continue with
|
|
* the next opcode (match=1; break;), otherwise
|
|
* the packet must be dropped (set retval,
|
|
* break loops with l=0, done=1)
|
|
*
|
|
* O_PROBE_STATE and O_CHECK_STATE: these opcodes
|
|
* cause a lookup of the state table, and a jump
|
|
* to the 'action' part of the parent rule
|
|
* if an entry is found, or
|
|
* (CHECK_STATE only) a jump to the next rule if
|
|
* the entry is not found.
|
|
* The result of the lookup is cached so that
|
|
* further instances of these opcodes become NOPs.
|
|
* The jump to the next rule is done by setting
|
|
* l=0, cmdlen=0.
|
|
*
|
|
* O_SKIP_ACTION: this opcode is not a real 'action'
|
|
* either, and is stored right before the 'action'
|
|
* part of the rule, right after the O_KEEP_STATE
|
|
* opcode. It causes match failure so the real
|
|
* 'action' could be executed only if the rule
|
|
* is checked via dynamic rule from the state
|
|
* table, as in such case execution starts
|
|
* from the true 'action' opcode directly.
|
|
*
|
|
*/
|
|
case O_LIMIT:
|
|
case O_KEEP_STATE:
|
|
if (ipfw_dyn_install_state(chain, f,
|
|
(ipfw_insn_limit *)cmd, args, ulp,
|
|
pktlen, &dyn_info, tablearg)) {
|
|
/* error or limit violation */
|
|
retval = IP_FW_DENY;
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
}
|
|
match = 1;
|
|
break;
|
|
|
|
case O_PROBE_STATE:
|
|
case O_CHECK_STATE:
|
|
/*
|
|
* dynamic rules are checked at the first
|
|
* keep-state or check-state occurrence,
|
|
* with the result being stored in dyn_info.
|
|
* The compiler introduces a PROBE_STATE
|
|
* instruction for us when we have a
|
|
* KEEP_STATE (because PROBE_STATE needs
|
|
* to be run first).
|
|
*/
|
|
if (DYN_LOOKUP_NEEDED(&dyn_info, cmd) &&
|
|
(q = ipfw_dyn_lookup_state(args, ulp,
|
|
pktlen, cmd, &dyn_info)) != NULL) {
|
|
/*
|
|
* Found dynamic entry, jump to the
|
|
* 'action' part of the parent rule
|
|
* by setting f, cmd, l and clearing
|
|
* cmdlen.
|
|
*/
|
|
f = q;
|
|
f_pos = dyn_info.f_pos;
|
|
cmd = ACTION_PTR(f);
|
|
l = f->cmd_len - f->act_ofs;
|
|
cmdlen = 0;
|
|
match = 1;
|
|
break;
|
|
}
|
|
/*
|
|
* Dynamic entry not found. If CHECK_STATE,
|
|
* skip to next rule, if PROBE_STATE just
|
|
* ignore and continue with next opcode.
|
|
*/
|
|
if (cmd->opcode == O_CHECK_STATE)
|
|
l = 0; /* exit inner loop */
|
|
match = 1;
|
|
break;
|
|
|
|
case O_SKIP_ACTION:
|
|
match = 0; /* skip to the next rule */
|
|
l = 0; /* exit inner loop */
|
|
break;
|
|
|
|
case O_ACCEPT:
|
|
retval = 0; /* accept */
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
break;
|
|
|
|
case O_PIPE:
|
|
case O_QUEUE:
|
|
set_match(args, f_pos, chain);
|
|
args->rule.info = TARG(cmd->arg1, pipe);
|
|
if (cmd->opcode == O_PIPE)
|
|
args->rule.info |= IPFW_IS_PIPE;
|
|
if (V_fw_one_pass)
|
|
args->rule.info |= IPFW_ONEPASS;
|
|
retval = IP_FW_DUMMYNET;
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
break;
|
|
|
|
case O_DIVERT:
|
|
case O_TEE:
|
|
if (args->flags & IPFW_ARGS_ETHER)
|
|
break; /* not on layer 2 */
|
|
/* otherwise this is terminal */
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
retval = (cmd->opcode == O_DIVERT) ?
|
|
IP_FW_DIVERT : IP_FW_TEE;
|
|
set_match(args, f_pos, chain);
|
|
args->rule.info = TARG(cmd->arg1, divert);
|
|
break;
|
|
|
|
case O_COUNT:
|
|
IPFW_INC_RULE_COUNTER(f, pktlen);
|
|
l = 0; /* exit inner loop */
|
|
break;
|
|
|
|
case O_SKIPTO:
|
|
IPFW_INC_RULE_COUNTER(f, pktlen);
|
|
f_pos = JUMP(chain, f, cmd->arg1, tablearg, 0);
|
|
/*
|
|
* Skip disabled rules, and re-enter
|
|
* the inner loop with the correct
|
|
* f_pos, f, l and cmd.
|
|
* Also clear cmdlen and skip_or
|
|
*/
|
|
for (; f_pos < chain->n_rules - 1 &&
|
|
(V_set_disable &
|
|
(1 << chain->map[f_pos]->set));
|
|
f_pos++)
|
|
;
|
|
/* Re-enter the inner loop at the skipto rule. */
|
|
f = chain->map[f_pos];
|
|
l = f->cmd_len;
|
|
cmd = f->cmd;
|
|
match = 1;
|
|
cmdlen = 0;
|
|
skip_or = 0;
|
|
continue;
|
|
break; /* not reached */
|
|
|
|
case O_CALLRETURN: {
|
|
/*
|
|
* Implementation of `subroutine' call/return,
|
|
* in the stack carried in an mbuf tag. This
|
|
* is different from `skipto' in that any call
|
|
* address is possible (`skipto' must prevent
|
|
* backward jumps to avoid endless loops).
|
|
* We have `return' action when F_NOT flag is
|
|
* present. The `m_tag_id' field is used as
|
|
* stack pointer.
|
|
*/
|
|
struct m_tag *mtag;
|
|
uint16_t jmpto, *stack;
|
|
|
|
#define IS_CALL ((cmd->len & F_NOT) == 0)
|
|
#define IS_RETURN ((cmd->len & F_NOT) != 0)
|
|
/*
|
|
* Hand-rolled version of m_tag_locate() with
|
|
* wildcard `type'.
|
|
* If not already tagged, allocate new tag.
|
|
*/
|
|
mtag = m_tag_first(m);
|
|
while (mtag != NULL) {
|
|
if (mtag->m_tag_cookie ==
|
|
MTAG_IPFW_CALL)
|
|
break;
|
|
mtag = m_tag_next(m, mtag);
|
|
}
|
|
if (mtag == NULL && IS_CALL) {
|
|
mtag = m_tag_alloc(MTAG_IPFW_CALL, 0,
|
|
IPFW_CALLSTACK_SIZE *
|
|
sizeof(uint16_t), M_NOWAIT);
|
|
if (mtag != NULL)
|
|
m_tag_prepend(m, mtag);
|
|
}
|
|
|
|
/*
|
|
* On error both `call' and `return' just
|
|
* continue with next rule.
|
|
*/
|
|
if (IS_RETURN && (mtag == NULL ||
|
|
mtag->m_tag_id == 0)) {
|
|
l = 0; /* exit inner loop */
|
|
break;
|
|
}
|
|
if (IS_CALL && (mtag == NULL ||
|
|
mtag->m_tag_id >= IPFW_CALLSTACK_SIZE)) {
|
|
printf("ipfw: call stack error, "
|
|
"go to next rule\n");
|
|
l = 0; /* exit inner loop */
|
|
break;
|
|
}
|
|
|
|
IPFW_INC_RULE_COUNTER(f, pktlen);
|
|
stack = (uint16_t *)(mtag + 1);
|
|
|
|
/*
|
|
* The `call' action may use cached f_pos
|
|
* (in f->next_rule), whose version is written
|
|
* in f->next_rule.
|
|
* The `return' action, however, doesn't have
|
|
* fixed jump address in cmd->arg1 and can't use
|
|
* cache.
|
|
*/
|
|
if (IS_CALL) {
|
|
stack[mtag->m_tag_id] = f->rulenum;
|
|
mtag->m_tag_id++;
|
|
f_pos = JUMP(chain, f, cmd->arg1,
|
|
tablearg, 1);
|
|
} else { /* `return' action */
|
|
mtag->m_tag_id--;
|
|
jmpto = stack[mtag->m_tag_id] + 1;
|
|
f_pos = ipfw_find_rule(chain, jmpto, 0);
|
|
}
|
|
|
|
/*
|
|
* Skip disabled rules, and re-enter
|
|
* the inner loop with the correct
|
|
* f_pos, f, l and cmd.
|
|
* Also clear cmdlen and skip_or
|
|
*/
|
|
for (; f_pos < chain->n_rules - 1 &&
|
|
(V_set_disable &
|
|
(1 << chain->map[f_pos]->set)); f_pos++)
|
|
;
|
|
/* Re-enter the inner loop at the dest rule. */
|
|
f = chain->map[f_pos];
|
|
l = f->cmd_len;
|
|
cmd = f->cmd;
|
|
cmdlen = 0;
|
|
skip_or = 0;
|
|
continue;
|
|
break; /* NOTREACHED */
|
|
}
|
|
#undef IS_CALL
|
|
#undef IS_RETURN
|
|
|
|
case O_REJECT:
|
|
/*
|
|
* Drop the packet and send a reject notice
|
|
* if the packet is not ICMP (or is an ICMP
|
|
* query), and it is not multicast/broadcast.
|
|
*/
|
|
if (hlen > 0 && is_ipv4 && offset == 0 &&
|
|
(proto != IPPROTO_ICMP ||
|
|
is_icmp_query(ICMP(ulp))) &&
|
|
!(m->m_flags & (M_BCAST|M_MCAST)) &&
|
|
!IN_MULTICAST(ntohl(dst_ip.s_addr))) {
|
|
send_reject(args, cmd, iplen, ip);
|
|
m = args->m;
|
|
}
|
|
/* FALLTHROUGH */
|
|
#ifdef INET6
|
|
case O_UNREACH6:
|
|
if (hlen > 0 && is_ipv6 &&
|
|
((offset & IP6F_OFF_MASK) == 0) &&
|
|
(proto != IPPROTO_ICMPV6 ||
|
|
(is_icmp6_query(icmp6_type) == 1)) &&
|
|
!(m->m_flags & (M_BCAST|M_MCAST)) &&
|
|
!IN6_IS_ADDR_MULTICAST(
|
|
&args->f_id.dst_ip6)) {
|
|
send_reject6(args,
|
|
cmd->opcode == O_REJECT ?
|
|
map_icmp_unreach(cmd->arg1):
|
|
cmd->arg1, hlen,
|
|
(struct ip6_hdr *)ip);
|
|
m = args->m;
|
|
}
|
|
/* FALLTHROUGH */
|
|
#endif
|
|
case O_DENY:
|
|
retval = IP_FW_DENY;
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
break;
|
|
|
|
case O_FORWARD_IP:
|
|
if (args->flags & IPFW_ARGS_ETHER)
|
|
break; /* not valid on layer2 pkts */
|
|
if (q != f ||
|
|
dyn_info.direction == MATCH_FORWARD) {
|
|
struct sockaddr_in *sa;
|
|
|
|
sa = &(((ipfw_insn_sa *)cmd)->sa);
|
|
if (sa->sin_addr.s_addr == INADDR_ANY) {
|
|
#ifdef INET6
|
|
/*
|
|
* We use O_FORWARD_IP opcode for
|
|
* fwd rule with tablearg, but tables
|
|
* now support IPv6 addresses. And
|
|
* when we are inspecting IPv6 packet,
|
|
* we can use nh6 field from
|
|
* table_value as next_hop6 address.
|
|
*/
|
|
if (is_ipv6) {
|
|
struct ip_fw_nh6 *nh6;
|
|
|
|
args->flags |= IPFW_ARGS_NH6;
|
|
nh6 = &args->hopstore6;
|
|
nh6->sin6_addr = TARG_VAL(
|
|
chain, tablearg, nh6);
|
|
nh6->sin6_port = sa->sin_port;
|
|
nh6->sin6_scope_id = TARG_VAL(
|
|
chain, tablearg, zoneid);
|
|
} else
|
|
#endif
|
|
{
|
|
args->flags |= IPFW_ARGS_NH4;
|
|
args->hopstore.sin_port =
|
|
sa->sin_port;
|
|
sa = &args->hopstore;
|
|
sa->sin_family = AF_INET;
|
|
sa->sin_len = sizeof(*sa);
|
|
sa->sin_addr.s_addr = htonl(
|
|
TARG_VAL(chain, tablearg,
|
|
nh4));
|
|
}
|
|
} else {
|
|
args->flags |= IPFW_ARGS_NH4PTR;
|
|
args->next_hop = sa;
|
|
}
|
|
}
|
|
retval = IP_FW_PASS;
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
break;
|
|
|
|
#ifdef INET6
|
|
case O_FORWARD_IP6:
|
|
if (args->flags & IPFW_ARGS_ETHER)
|
|
break; /* not valid on layer2 pkts */
|
|
if (q != f ||
|
|
dyn_info.direction == MATCH_FORWARD) {
|
|
struct sockaddr_in6 *sin6;
|
|
|
|
sin6 = &(((ipfw_insn_sa6 *)cmd)->sa);
|
|
args->flags |= IPFW_ARGS_NH6PTR;
|
|
args->next_hop6 = sin6;
|
|
}
|
|
retval = IP_FW_PASS;
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
break;
|
|
#endif
|
|
|
|
case O_NETGRAPH:
|
|
case O_NGTEE:
|
|
set_match(args, f_pos, chain);
|
|
args->rule.info = TARG(cmd->arg1, netgraph);
|
|
if (V_fw_one_pass)
|
|
args->rule.info |= IPFW_ONEPASS;
|
|
retval = (cmd->opcode == O_NETGRAPH) ?
|
|
IP_FW_NETGRAPH : IP_FW_NGTEE;
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
break;
|
|
|
|
case O_SETFIB: {
|
|
uint32_t fib;
|
|
|
|
IPFW_INC_RULE_COUNTER(f, pktlen);
|
|
fib = TARG(cmd->arg1, fib) & 0x7FFF;
|
|
if (fib >= rt_numfibs)
|
|
fib = 0;
|
|
M_SETFIB(m, fib);
|
|
args->f_id.fib = fib; /* XXX */
|
|
l = 0; /* exit inner loop */
|
|
break;
|
|
}
|
|
|
|
case O_SETDSCP: {
|
|
uint16_t code;
|
|
|
|
code = TARG(cmd->arg1, dscp) & 0x3F;
|
|
l = 0; /* exit inner loop */
|
|
if (is_ipv4) {
|
|
uint16_t old;
|
|
|
|
old = *(uint16_t *)ip;
|
|
ip->ip_tos = (code << 2) |
|
|
(ip->ip_tos & 0x03);
|
|
ip->ip_sum = cksum_adjust(ip->ip_sum,
|
|
old, *(uint16_t *)ip);
|
|
} else if (is_ipv6) {
|
|
/* update cached value */
|
|
args->f_id.flow_id6 =
|
|
ntohl(*(uint32_t *)ip) & ~0x0FC00000;
|
|
args->f_id.flow_id6 |= code << 22;
|
|
|
|
*((uint32_t *)ip) =
|
|
htonl(args->f_id.flow_id6);
|
|
} else
|
|
break;
|
|
|
|
IPFW_INC_RULE_COUNTER(f, pktlen);
|
|
break;
|
|
}
|
|
|
|
case O_NAT:
|
|
l = 0; /* exit inner loop */
|
|
done = 1; /* exit outer loop */
|
|
/*
|
|
* Ensure that we do not invoke NAT handler for
|
|
* non IPv4 packets. Libalias expects only IPv4.
|
|
*/
|
|
if (!is_ipv4 || !IPFW_NAT_LOADED) {
|
|
retval = IP_FW_DENY;
|
|
break;
|
|
}
|
|
|
|
struct cfg_nat *t;
|
|
int nat_id;
|
|
|
|
args->rule.info = 0;
|
|
set_match(args, f_pos, chain);
|
|
/* Check if this is 'global' nat rule */
|
|
if (cmd->arg1 == IP_FW_NAT44_GLOBAL) {
|
|
retval = ipfw_nat_ptr(args, NULL, m);
|
|
break;
|
|
}
|
|
t = ((ipfw_insn_nat *)cmd)->nat;
|
|
if (t == NULL) {
|
|
nat_id = TARG(cmd->arg1, nat);
|
|
t = (*lookup_nat_ptr)(&chain->nat, nat_id);
|
|
|
|
if (t == NULL) {
|
|
retval = IP_FW_DENY;
|
|
break;
|
|
}
|
|
if (cmd->arg1 != IP_FW_TARG)
|
|
((ipfw_insn_nat *)cmd)->nat = t;
|
|
}
|
|
retval = ipfw_nat_ptr(args, t, m);
|
|
break;
|
|
|
|
case O_REASS: {
|
|
int ip_off;
|
|
|
|
l = 0; /* in any case exit inner loop */
|
|
if (is_ipv6) /* IPv6 is not supported yet */
|
|
break;
|
|
IPFW_INC_RULE_COUNTER(f, pktlen);
|
|
ip_off = ntohs(ip->ip_off);
|
|
|
|
/* if not fragmented, go to next rule */
|
|
if ((ip_off & (IP_MF | IP_OFFMASK)) == 0)
|
|
break;
|
|
|
|
args->m = m = ip_reass(m);
|
|
|
|
/*
|
|
* do IP header checksum fixup.
|
|
*/
|
|
if (m == NULL) { /* fragment got swallowed */
|
|
retval = IP_FW_DENY;
|
|
} else { /* good, packet complete */
|
|
int hlen;
|
|
|
|
ip = mtod(m, struct ip *);
|
|
hlen = ip->ip_hl << 2;
|
|
ip->ip_sum = 0;
|
|
if (hlen == sizeof(struct ip))
|
|
ip->ip_sum = in_cksum_hdr(ip);
|
|
else
|
|
ip->ip_sum = in_cksum(m, hlen);
|
|
retval = IP_FW_REASS;
|
|
args->rule.info = 0;
|
|
set_match(args, f_pos, chain);
|
|
}
|
|
done = 1; /* exit outer loop */
|
|
break;
|
|
}
|
|
|
|
case O_SETMARK: {
|
|
l = 0; /* exit inner loop */
|
|
args->rule.pkt_mark = (
|
|
(cmd->arg1 == IP_FW_TARG) ?
|
|
TARG_VAL(chain, tablearg, mark) :
|
|
((ipfw_insn_u32 *)cmd)->d[0]);
|
|
|
|
IPFW_INC_RULE_COUNTER(f, pktlen);
|
|
break;
|
|
}
|
|
|
|
case O_EXTERNAL_ACTION:
|
|
l = 0; /* in any case exit inner loop */
|
|
retval = ipfw_run_eaction(chain, args,
|
|
cmd, &done);
|
|
/*
|
|
* If both @retval and @done are zero,
|
|
* consider this as rule matching and
|
|
* update counters.
|
|
*/
|
|
if (retval == 0 && done == 0) {
|
|
IPFW_INC_RULE_COUNTER(f, pktlen);
|
|
/*
|
|
* Reset the result of the last
|
|
* dynamic state lookup.
|
|
* External action can change
|
|
* @args content, and it may be
|
|
* used for new state lookup later.
|
|
*/
|
|
DYN_INFO_INIT(&dyn_info);
|
|
}
|
|
break;
|
|
|
|
default:
|
|
panic("-- unknown opcode %d\n", cmd->opcode);
|
|
} /* end of switch() on opcodes */
|
|
/*
|
|
* if we get here with l=0, then match is irrelevant.
|
|
*/
|
|
|
|
if (cmd->len & F_NOT)
|
|
match = !match;
|
|
|
|
if (match) {
|
|
if (cmd->len & F_OR)
|
|
skip_or = 1;
|
|
} else {
|
|
if (!(cmd->len & F_OR)) /* not an OR block, */
|
|
break; /* try next rule */
|
|
}
|
|
|
|
} /* end of inner loop, scan opcodes */
|
|
#undef PULLUP_LEN
|
|
#undef PULLUP_LEN_LOCKED
|
|
|
|
if (done)
|
|
break;
|
|
|
|
/* next_rule:; */ /* try next rule */
|
|
|
|
} /* end of outer for, scan rules */
|
|
|
|
if (done) {
|
|
struct ip_fw *rule = chain->map[f_pos];
|
|
/* Update statistics */
|
|
IPFW_INC_RULE_COUNTER(rule, pktlen);
|
|
IPFW_PROBE(rule__matched, retval,
|
|
is_ipv4 ? AF_INET : AF_INET6,
|
|
is_ipv4 ? (uintptr_t)&src_ip :
|
|
(uintptr_t)&args->f_id.src_ip6,
|
|
is_ipv4 ? (uintptr_t)&dst_ip :
|
|
(uintptr_t)&args->f_id.dst_ip6,
|
|
args, rule);
|
|
} else {
|
|
retval = IP_FW_DENY;
|
|
printf("ipfw: ouch!, skip past end of rules, denying packet\n");
|
|
}
|
|
IPFW_PF_RUNLOCK(chain);
|
|
#ifdef __FreeBSD__
|
|
if (ucred_cache != NULL)
|
|
crfree(ucred_cache);
|
|
#endif
|
|
return (retval);
|
|
|
|
pullup_failed:
|
|
if (V_fw_verbose)
|
|
printf("ipfw: pullup failed\n");
|
|
return (IP_FW_DENY);
|
|
}
|
|
|
|
/*
|
|
* Set maximum number of tables that can be used in given VNET ipfw instance.
|
|
*/
|
|
#ifdef SYSCTL_NODE
|
|
static int
|
|
sysctl_ipfw_table_num(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error;
|
|
unsigned int ntables;
|
|
|
|
ntables = V_fw_tables_max;
|
|
|
|
error = sysctl_handle_int(oidp, &ntables, 0, req);
|
|
/* Read operation or some error */
|
|
if ((error != 0) || (req->newptr == NULL))
|
|
return (error);
|
|
|
|
return (ipfw_resize_tables(&V_layer3_chain, ntables));
|
|
}
|
|
|
|
/*
|
|
* Switches table namespace between global and per-set.
|
|
*/
|
|
static int
|
|
sysctl_ipfw_tables_sets(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error;
|
|
unsigned int sets;
|
|
|
|
sets = V_fw_tables_sets;
|
|
|
|
error = sysctl_handle_int(oidp, &sets, 0, req);
|
|
/* Read operation or some error */
|
|
if ((error != 0) || (req->newptr == NULL))
|
|
return (error);
|
|
|
|
return (ipfw_switch_tables_namespace(&V_layer3_chain, sets));
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Module and VNET glue
|
|
*/
|
|
|
|
/*
|
|
* Stuff that must be initialised only on boot or module load
|
|
*/
|
|
static int
|
|
ipfw_init(void)
|
|
{
|
|
int error = 0;
|
|
|
|
/*
|
|
* Only print out this stuff the first time around,
|
|
* when called from the sysinit code.
|
|
*/
|
|
printf("ipfw2 "
|
|
#ifdef INET6
|
|
"(+ipv6) "
|
|
#endif
|
|
"initialized, divert %s, nat %s, "
|
|
"default to %s, logging ",
|
|
#ifdef IPDIVERT
|
|
"enabled",
|
|
#else
|
|
"loadable",
|
|
#endif
|
|
#ifdef IPFIREWALL_NAT
|
|
"enabled",
|
|
#else
|
|
"loadable",
|
|
#endif
|
|
default_to_accept ? "accept" : "deny");
|
|
|
|
/*
|
|
* Note: V_xxx variables can be accessed here but the vnet specific
|
|
* initializer may not have been called yet for the VIMAGE case.
|
|
* Tuneables will have been processed. We will print out values for
|
|
* the default vnet.
|
|
* XXX This should all be rationalized AFTER 8.0
|
|
*/
|
|
if (V_fw_verbose == 0)
|
|
printf("disabled\n");
|
|
else if (V_verbose_limit == 0)
|
|
printf("unlimited\n");
|
|
else
|
|
printf("limited to %d packets/entry by default\n",
|
|
V_verbose_limit);
|
|
|
|
/* Check user-supplied table count for validness */
|
|
if (default_fw_tables > IPFW_TABLES_MAX)
|
|
default_fw_tables = IPFW_TABLES_MAX;
|
|
|
|
ipfw_init_sopt_handler();
|
|
ipfw_init_obj_rewriter();
|
|
ipfw_iface_init();
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Called for the removal of the last instance only on module unload.
|
|
*/
|
|
static void
|
|
ipfw_destroy(void)
|
|
{
|
|
|
|
ipfw_iface_destroy();
|
|
ipfw_destroy_sopt_handler();
|
|
ipfw_destroy_obj_rewriter();
|
|
printf("IP firewall unloaded\n");
|
|
}
|
|
|
|
/*
|
|
* Stuff that must be initialized for every instance
|
|
* (including the first of course).
|
|
*/
|
|
static int
|
|
vnet_ipfw_init(const void *unused)
|
|
{
|
|
int error, first;
|
|
struct ip_fw *rule = NULL;
|
|
struct ip_fw_chain *chain;
|
|
|
|
chain = &V_layer3_chain;
|
|
|
|
first = IS_DEFAULT_VNET(curvnet) ? 1 : 0;
|
|
|
|
/* First set up some values that are compile time options */
|
|
V_autoinc_step = 100; /* bounded to 1..1000 in add_rule() */
|
|
V_fw_deny_unknown_exthdrs = 1;
|
|
#ifdef IPFIREWALL_VERBOSE
|
|
V_fw_verbose = 1;
|
|
#endif
|
|
#ifdef IPFIREWALL_VERBOSE_LIMIT
|
|
V_verbose_limit = IPFIREWALL_VERBOSE_LIMIT;
|
|
#endif
|
|
#ifdef IPFIREWALL_NAT
|
|
LIST_INIT(&chain->nat);
|
|
#endif
|
|
|
|
/* Init shared services hash table */
|
|
ipfw_init_srv(chain);
|
|
|
|
ipfw_init_counters();
|
|
/* Set initial number of tables */
|
|
V_fw_tables_max = default_fw_tables;
|
|
error = ipfw_init_tables(chain, first);
|
|
if (error) {
|
|
printf("ipfw2: setting up tables failed\n");
|
|
free(chain->map, M_IPFW);
|
|
free(rule, M_IPFW);
|
|
return (ENOSPC);
|
|
}
|
|
|
|
IPFW_LOCK_INIT(chain);
|
|
|
|
/* fill and insert the default rule */
|
|
rule = ipfw_alloc_rule(chain, sizeof(struct ip_fw));
|
|
rule->flags |= IPFW_RULE_NOOPT;
|
|
rule->cmd_len = 1;
|
|
rule->cmd[0].len = 1;
|
|
rule->cmd[0].opcode = default_to_accept ? O_ACCEPT : O_DENY;
|
|
chain->default_rule = rule;
|
|
ipfw_add_protected_rule(chain, rule, 0);
|
|
|
|
ipfw_dyn_init(chain);
|
|
ipfw_eaction_init(chain, first);
|
|
#ifdef LINEAR_SKIPTO
|
|
ipfw_init_skipto_cache(chain);
|
|
#endif
|
|
ipfw_bpf_init(first);
|
|
|
|
/* First set up some values that are compile time options */
|
|
V_ipfw_vnet_ready = 1; /* Open for business */
|
|
|
|
/*
|
|
* Hook the sockopt handler and pfil hooks for ipv4 and ipv6.
|
|
* Even if the latter two fail we still keep the module alive
|
|
* because the sockopt and layer2 paths are still useful.
|
|
* ipfw[6]_hook return 0 on success, ENOENT on failure,
|
|
* so we can ignore the exact return value and just set a flag.
|
|
*
|
|
* Note that V_fw[6]_enable are manipulated by a SYSCTL_PROC so
|
|
* changes in the underlying (per-vnet) variables trigger
|
|
* immediate hook()/unhook() calls.
|
|
* In layer2 we have the same behaviour, except that V_ether_ipfw
|
|
* is checked on each packet because there are no pfil hooks.
|
|
*/
|
|
V_ip_fw_ctl_ptr = ipfw_ctl3;
|
|
error = ipfw_attach_hooks();
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Called for the removal of each instance.
|
|
*/
|
|
static int
|
|
vnet_ipfw_uninit(const void *unused)
|
|
{
|
|
struct ip_fw *reap;
|
|
struct ip_fw_chain *chain = &V_layer3_chain;
|
|
int i, last;
|
|
|
|
V_ipfw_vnet_ready = 0; /* tell new callers to go away */
|
|
/*
|
|
* disconnect from ipv4, ipv6, layer2 and sockopt.
|
|
* Then grab, release and grab again the WLOCK so we make
|
|
* sure the update is propagated and nobody will be in.
|
|
*/
|
|
ipfw_detach_hooks();
|
|
V_ip_fw_ctl_ptr = NULL;
|
|
|
|
last = IS_DEFAULT_VNET(curvnet) ? 1 : 0;
|
|
|
|
IPFW_UH_WLOCK(chain);
|
|
IPFW_UH_WUNLOCK(chain);
|
|
|
|
ipfw_dyn_uninit(0); /* run the callout_drain */
|
|
|
|
IPFW_UH_WLOCK(chain);
|
|
|
|
reap = NULL;
|
|
IPFW_WLOCK(chain);
|
|
for (i = 0; i < chain->n_rules; i++)
|
|
ipfw_reap_add(chain, &reap, chain->map[i]);
|
|
free(chain->map, M_IPFW);
|
|
#ifdef LINEAR_SKIPTO
|
|
ipfw_destroy_skipto_cache(chain);
|
|
#endif
|
|
IPFW_WUNLOCK(chain);
|
|
IPFW_UH_WUNLOCK(chain);
|
|
ipfw_destroy_tables(chain, last);
|
|
ipfw_eaction_uninit(chain, last);
|
|
if (reap != NULL)
|
|
ipfw_reap_rules(reap);
|
|
vnet_ipfw_iface_destroy(chain);
|
|
ipfw_destroy_srv(chain);
|
|
IPFW_LOCK_DESTROY(chain);
|
|
ipfw_dyn_uninit(1); /* free the remaining parts */
|
|
ipfw_destroy_counters();
|
|
ipfw_bpf_uninit(last);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Module event handler.
|
|
* In general we have the choice of handling most of these events by the
|
|
* event handler or by the (VNET_)SYS(UN)INIT handlers. I have chosen to
|
|
* use the SYSINIT handlers as they are more capable of expressing the
|
|
* flow of control during module and vnet operations, so this is just
|
|
* a skeleton. Note there is no SYSINIT equivalent of the module
|
|
* SHUTDOWN handler, but we don't have anything to do in that case anyhow.
|
|
*/
|
|
static int
|
|
ipfw_modevent(module_t mod, int type, void *unused)
|
|
{
|
|
int err = 0;
|
|
|
|
switch (type) {
|
|
case MOD_LOAD:
|
|
/* Called once at module load or
|
|
* system boot if compiled in. */
|
|
break;
|
|
case MOD_QUIESCE:
|
|
/* Called before unload. May veto unloading. */
|
|
break;
|
|
case MOD_UNLOAD:
|
|
/* Called during unload. */
|
|
break;
|
|
case MOD_SHUTDOWN:
|
|
/* Called during system shutdown. */
|
|
break;
|
|
default:
|
|
err = EOPNOTSUPP;
|
|
break;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static moduledata_t ipfwmod = {
|
|
"ipfw",
|
|
ipfw_modevent,
|
|
0
|
|
};
|
|
|
|
/* Define startup order. */
|
|
#define IPFW_SI_SUB_FIREWALL SI_SUB_PROTO_FIREWALL
|
|
#define IPFW_MODEVENT_ORDER (SI_ORDER_ANY - 255) /* On boot slot in here. */
|
|
#define IPFW_MODULE_ORDER (IPFW_MODEVENT_ORDER + 1) /* A little later. */
|
|
#define IPFW_VNET_ORDER (IPFW_MODEVENT_ORDER + 2) /* Later still. */
|
|
|
|
DECLARE_MODULE(ipfw, ipfwmod, IPFW_SI_SUB_FIREWALL, IPFW_MODEVENT_ORDER);
|
|
FEATURE(ipfw_ctl3, "ipfw new sockopt calls");
|
|
MODULE_VERSION(ipfw, 3);
|
|
/* should declare some dependencies here */
|
|
|
|
/*
|
|
* Starting up. Done in order after ipfwmod() has been called.
|
|
* VNET_SYSINIT is also called for each existing vnet and each new vnet.
|
|
*/
|
|
SYSINIT(ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER,
|
|
ipfw_init, NULL);
|
|
VNET_SYSINIT(vnet_ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER,
|
|
vnet_ipfw_init, NULL);
|
|
|
|
/*
|
|
* Closing up shop. These are done in REVERSE ORDER, but still
|
|
* after ipfwmod() has been called. Not called on reboot.
|
|
* VNET_SYSUNINIT is also called for each exiting vnet as it exits.
|
|
* or when the module is unloaded.
|
|
*/
|
|
SYSUNINIT(ipfw_destroy, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER,
|
|
ipfw_destroy, NULL);
|
|
VNET_SYSUNINIT(vnet_ipfw_uninit, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER,
|
|
vnet_ipfw_uninit, NULL);
|
|
/* end of file */
|