--- /dev/null
+/*-
+ * Copyright (c) 2002 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: src/sys/netinet/ip_fw2.c,v 1.175.2.13 2008/10/30 16:29:04 bz Exp $");
+
+#define DEB(x)
+#define DDB(x) x
+
+/*
+ * Implement IP packet firewall (new version)
+ */
+
+#if !defined(KLD_MODULE)
+#include "opt_ipfw.h"
+#include "opt_ipdivert.h"
+#include "opt_ipdn.h"
+#include "opt_inet.h"
+#ifndef INET
+#error IPFIREWALL requires INET.
+#endif /* INET */
+#endif
+#include "opt_inet6.h"
+#include "opt_ipsec.h"
+#include "opt_mac.h"
+
+#include <sys/param.h>
+#include <sys/systm.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/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/radix.h>
+#include <net/route.h>
+#include <net/pf_mtag.h>
+
+#define IPFW_INTERNAL /* Access to protected data structures in ip_fw.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_divert.h>
+#include <netinet/ip_dummynet.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 <netgraph/ng_ipfw.h>
+
+#include <netinet/ip6.h>
+#include <netinet/icmp6.h>
+#ifdef INET6
+#include <netinet6/scope6_var.h>
+#endif
+
+#include <machine/in_cksum.h> /* XXX for in_cksum */
+
+#ifdef MAC
+#include <security/mac/mac_framework.h>
+#endif
+
+#include "missing.h"
+
+/*
+ * set_disable contains one bit per set value (0..31).
+ * If the bit is set, all rules with 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 explicitly.
+ */
+static u_int32_t set_disable;
+static int fw_verbose;
+static struct callout ipfw_timeout;
+static int verbose_limit;
+
+static uma_zone_t ipfw_dyn_rule_zone;
+
+/*
+ * Data structure to cache our ucred related
+ * information. This structure only gets used if
+ * the user specified UID/GID based constraints in
+ * a firewall rule.
+ */
+struct ip_fw_ugid {
+ gid_t fw_groups[NGROUPS];
+ int fw_ngroups;
+ uid_t fw_uid;
+ int fw_prid;
+};
+
+/*
+ * list of rules for layer 3
+ */
+struct ip_fw_chain layer3_chain;
+
+MALLOC_DEFINE(M_IPFW, "IpFw/IpAcct", "IpFw/IpAcct chain's");
+MALLOC_DEFINE(M_IPFW_TBL, "ipfw_tbl", "IpFw tables");
+#define IPFW_NAT_LOADED (ipfw_nat_ptr != NULL)
+ipfw_nat_t *ipfw_nat_ptr = NULL;
+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;
+
+struct table_entry {
+ struct radix_node rn[2];
+ struct sockaddr_in addr, mask;
+ u_int32_t value;
+};
+
+static int autoinc_step = 100; /* bounded to 1..1000 in add_rule() */
+
+extern int ipfw_chg_hook(SYSCTL_HANDLER_ARGS);
+
+#ifdef SYSCTL_NODE
+SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall");
+SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, enable,
+ CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3, &fw_enable, 0,
+ ipfw_chg_hook, "I", "Enable ipfw");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, autoinc_step, CTLFLAG_RW,
+ &autoinc_step, 0, "Rule number autincrement step");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, one_pass,
+ CTLFLAG_RW | CTLFLAG_SECURE3,
+ &fw_one_pass, 0,
+ "Only do a single pass through ipfw when using dummynet(4)");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose,
+ CTLFLAG_RW | CTLFLAG_SECURE3,
+ &fw_verbose, 0, "Log matches to ipfw rules");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit, CTLFLAG_RW,
+ &verbose_limit, 0, "Set upper limit of matches of ipfw rules logged");
+SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, default_rule, CTLFLAG_RD,
+ NULL, IPFW_DEFAULT_RULE, "The default/max possible rule number.");
+SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, tables_max, CTLFLAG_RD,
+ NULL, IPFW_TABLES_MAX, "The maximum number of tables.");
+#endif /* SYSCTL_NODE */
+
+/*
+ * Description of dynamic rules.
+ *
+ * Dynamic rules are stored in lists accessed through a hash table
+ * (ipfw_dyn_v) whose size is curr_dyn_buckets. This value can
+ * be modified through the sysctl variable dyn_buckets which is
+ * updated when the table becomes empty.
+ *
+ * XXX currently there is only one list, ipfw_dyn.
+ *
+ * When a packet is received, its address fields are first masked
+ * with the mask defined for the rule, then hashed, then matched
+ * against the entries in the corresponding list.
+ * Dynamic rules can be used for different purposes:
+ * + stateful rules;
+ * + enforcing limits on the number of sessions;
+ * + in-kernel NAT (not implemented yet)
+ *
+ * The lifetime of dynamic rules is regulated by dyn_*_lifetime,
+ * measured in seconds and depending on the flags.
+ *
+ * The total number of dynamic rules is stored in dyn_count.
+ * The max number of dynamic rules is dyn_max. When we reach
+ * the maximum number of rules we do not create anymore. This is
+ * done to avoid consuming too much memory, but also too much
+ * time when searching on each packet (ideally, we should try instead
+ * to put a limit on the length of the list on each bucket...).
+ *
+ * Each dynamic rule holds a pointer to the parent ipfw rule so
+ * we know what action to perform. Dynamic rules are removed when
+ * the parent rule is deleted. XXX we should make them survive.
+ *
+ * There are some limitations with dynamic rules -- we do not
+ * obey the 'randomized match', and we do not do multiple
+ * passes through the firewall. XXX check the latter!!!
+ */
+static ipfw_dyn_rule **ipfw_dyn_v = NULL;
+static u_int32_t dyn_buckets = 256; /* must be power of 2 */
+static u_int32_t curr_dyn_buckets = 256; /* must be power of 2 */
+
+#if defined( __linux__ ) || defined( _WIN32 )
+DEFINE_SPINLOCK(ipfw_dyn_mtx);
+#else
+static struct mtx ipfw_dyn_mtx; /* mutex guarding dynamic rules */
+#endif /* !__linux__ */
+#define IPFW_DYN_LOCK_INIT() \
+ mtx_init(&ipfw_dyn_mtx, "IPFW dynamic rules", NULL, MTX_DEF)
+#define IPFW_DYN_LOCK_DESTROY() mtx_destroy(&ipfw_dyn_mtx)
+#define IPFW_DYN_LOCK() mtx_lock(&ipfw_dyn_mtx)
+#define IPFW_DYN_UNLOCK() mtx_unlock(&ipfw_dyn_mtx)
+#define IPFW_DYN_LOCK_ASSERT() mtx_assert(&ipfw_dyn_mtx, MA_OWNED)
+
+/*
+ * Timeouts for various events in handing dynamic rules.
+ */
+static u_int32_t dyn_ack_lifetime = 300;
+static u_int32_t dyn_syn_lifetime = 20;
+static u_int32_t dyn_fin_lifetime = 1;
+static u_int32_t dyn_rst_lifetime = 1;
+static u_int32_t dyn_udp_lifetime = 10;
+static u_int32_t dyn_short_lifetime = 5;
+
+/*
+ * Keepalives are sent if dyn_keepalive is set. They are sent every
+ * dyn_keepalive_period seconds, in the last dyn_keepalive_interval
+ * seconds of lifetime of a rule.
+ * dyn_rst_lifetime and dyn_fin_lifetime should be strictly lower
+ * than dyn_keepalive_period.
+ */
+
+static u_int32_t dyn_keepalive_interval = 20;
+static u_int32_t dyn_keepalive_period = 5;
+static u_int32_t dyn_keepalive = 1; /* do send keepalives */
+
+static u_int32_t static_count; /* # of static rules */
+static u_int32_t static_len; /* size in bytes of static rules */
+static u_int32_t dyn_count; /* # of dynamic rules */
+static u_int32_t dyn_max = 4096; /* max # of dynamic rules */
+
+#ifdef SYSCTL_NODE
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_buckets, CTLFLAG_RW,
+ &dyn_buckets, 0, "Number of dyn. buckets");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, curr_dyn_buckets, CTLFLAG_RD,
+ &curr_dyn_buckets, 0, "Current Number of dyn. buckets");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_count, CTLFLAG_RD,
+ &dyn_count, 0, "Number of dyn. rules");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_max, CTLFLAG_RW,
+ &dyn_max, 0, "Max number of dyn. rules");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, static_count, CTLFLAG_RD,
+ &static_count, 0, "Number of static rules");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_ack_lifetime, CTLFLAG_RW,
+ &dyn_ack_lifetime, 0, "Lifetime of dyn. rules for acks");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_syn_lifetime, CTLFLAG_RW,
+ &dyn_syn_lifetime, 0, "Lifetime of dyn. rules for syn");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_fin_lifetime, CTLFLAG_RW,
+ &dyn_fin_lifetime, 0, "Lifetime of dyn. rules for fin");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_rst_lifetime, CTLFLAG_RW,
+ &dyn_rst_lifetime, 0, "Lifetime of dyn. rules for rst");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_udp_lifetime, CTLFLAG_RW,
+ &dyn_udp_lifetime, 0, "Lifetime of dyn. rules for UDP");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_short_lifetime, CTLFLAG_RW,
+ &dyn_short_lifetime, 0, "Lifetime of dyn. rules for other situations");
+SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_keepalive, CTLFLAG_RW,
+ &dyn_keepalive, 0, "Enable keepalives for dyn. rules");
+#endif /* SYSCTL_NODE */
+
+#ifdef INET6
+/*
+ * IPv6 specific variables
+ */
+#ifdef SYSCTL_NODE
+SYSCTL_DECL(_net_inet6_ip6);
+#endif /* SYSCTL_NODE */
+
+static struct sysctl_ctx_list ip6_fw_sysctl_ctx;
+static struct sysctl_oid *ip6_fw_sysctl_tree;
+#endif /* INET6 */
+
+static int fw_deny_unknown_exthdrs = 1;
+
+
+/*
+ * 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));
+}
+
+static int
+tcpopts_match(struct tcphdr *tcp, ipfw_insn *cmd)
+{
+ int optlen, bits = 0;
+ u_char *cp = (u_char *)(tcp + 1);
+ int x = (tcp->th_off << 2) - sizeof(struct tcphdr);
+
+ for (; x > 0; x -= optlen, cp += optlen) {
+ int opt = cp[0];
+ if (opt == TCPOPT_EOL)
+ break;
+ if (opt == TCPOPT_NOP)
+ optlen = 1;
+ else {
+ optlen = cp[1];
+ if (optlen <= 0)
+ break;
+ }
+
+ switch (opt) {
+
+ default:
+ break;
+
+ case TCPOPT_MAXSEG:
+ bits |= IP_FW_TCPOPT_MSS;
+ break;
+
+ case TCPOPT_WINDOW:
+ bits |= IP_FW_TCPOPT_WINDOW;
+ break;
+
+ case TCPOPT_SACK_PERMITTED:
+ case TCPOPT_SACK:
+ bits |= IP_FW_TCPOPT_SACK;
+ break;
+
+ case TCPOPT_TIMESTAMP:
+ bits |= IP_FW_TCPOPT_TS;
+ break;
+
+ }
+ }
+ return (flags_match(cmd, bits));
+}
+
+static int
+iface_match(struct ifnet *ifp, ipfw_insn_if *cmd)
+{
+ 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 */
+ /* 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( __linux__ ) && !defined( _WIN32 )
+ struct ifaddr *ia;
+
+ /* XXX lock? */
+ TAILQ_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
+ }
+ return(0); /* no match, fail ... */
+}
+
+#if !defined( __linux__ ) && !defined( _WIN32 )
+/*
+ * 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 syntax is
+ * misleading. 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)
+{
+ struct route ro;
+ struct sockaddr_in *dst;
+
+ bzero(&ro, sizeof(ro));
+
+ dst = (struct sockaddr_in *)&(ro.ro_dst);
+ dst->sin_family = AF_INET;
+ dst->sin_len = sizeof(*dst);
+ dst->sin_addr = src;
+ in_rtalloc_ign(&ro, RTF_CLONING, fib);
+
+ if (ro.ro_rt == 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():
+ * if useloopback == 1 routing entry (via lo0) for our own address
+ * may exist, so we need to handle routing assymetry.
+ */
+ if (ifp != NULL && ro.ro_rt->rt_ifa->ifa_ifp != ifp) {
+ RTFREE(ro.ro_rt);
+ return 0;
+ }
+
+ /* if no ifp provided, check if rtentry is not default route */
+ if (ifp == NULL &&
+ satosin(rt_key(ro.ro_rt))->sin_addr.s_addr == INADDR_ANY) {
+ RTFREE(ro.ro_rt);
+ return 0;
+ }
+
+ /* or if this is a blackhole/reject route */
+ if (ifp == NULL && ro.ro_rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
+ RTFREE(ro.ro_rt);
+ return 0;
+ }
+
+ /* found valid route */
+ RTFREE(ro.ro_rt);
+ return 1;
+}
+#endif
+
+#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 int
+search_ip6_addr_net (struct in6_addr * ip6_addr)
+{
+ struct ifnet *mdc;
+ struct ifaddr *mdc2;
+ struct in6_ifaddr *fdm;
+ struct in6_addr copia;
+
+ TAILQ_FOREACH(mdc, &ifnet, if_link)
+ TAILQ_FOREACH(mdc2, &mdc->if_addrlist, ifa_list) {
+ if (mdc2->ifa_addr->sa_family == AF_INET6) {
+ fdm = (struct in6_ifaddr *)mdc2;
+ copia = fdm->ia_addr.sin6_addr;
+ /* need for leaving scope_id in the sock_addr */
+ in6_clearscope(&copia);
+ if (IN6_ARE_ADDR_EQUAL(ip6_addr, &copia))
+ return 1;
+ }
+ }
+ return 0;
+}
+
+static int
+verify_path6(struct in6_addr *src, struct ifnet *ifp)
+{
+ struct route_in6 ro;
+ struct sockaddr_in6 *dst;
+
+ bzero(&ro, sizeof(ro));
+
+ dst = (struct sockaddr_in6 * )&(ro.ro_dst);
+ dst->sin6_family = AF_INET6;
+ dst->sin6_len = sizeof(*dst);
+ dst->sin6_addr = *src;
+ /* XXX MRT 0 for ipv6 at this time */
+ rtalloc_ign((struct route *)&ro, RTF_CLONING);
+
+ if (ro.ro_rt == 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,
+ * to support the case of sending packets to an address of our own.
+ * (where the former interface is the first argument of if_simloop()
+ * (=ifp), the latter is lo0)
+ */
+ if (ifp != NULL && ro.ro_rt->rt_ifa->ifa_ifp != ifp) {
+ RTFREE(ro.ro_rt);
+ return 0;
+ }
+
+ /* if no ifp provided, check if rtentry is not default route */
+ if (ifp == NULL &&
+ IN6_IS_ADDR_UNSPECIFIED(&satosin6(rt_key(ro.ro_rt))->sin6_addr)) {
+ RTFREE(ro.ro_rt);
+ return 0;
+ }
+
+ /* or if this is a blackhole/reject route */
+ if (ifp == NULL && ro.ro_rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
+ RTFREE(ro.ro_rt);
+ return 0;
+ }
+
+ /* found valid route */
+ RTFREE(ro.ro_rt);
+ return 1;
+
+}
+static __inline int
+hash_packet6(struct ipfw_flow_id *id)
+{
+ u_int32_t i;
+ i = (id->dst_ip6.__u6_addr.__u6_addr32[2]) ^
+ (id->dst_ip6.__u6_addr.__u6_addr32[3]) ^
+ (id->src_ip6.__u6_addr.__u6_addr32[2]) ^
+ (id->src_ip6.__u6_addr.__u6_addr32[3]) ^
+ (id->dst_port) ^ (id->src_port);
+ return i;
+}
+
+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 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_seq ack, seq;
+ int flags;
+ struct {
+ struct ip6_hdr ip6;
+ struct tcphdr th;
+ } ti;
+ tcp = (struct tcphdr *)((char *)ip6 + hlen);
+
+ if ((tcp->th_flags & TH_RST) != 0) {
+ m_freem(m);
+ args->m = NULL;
+ return;
+ }
+
+ ti.ip6 = *ip6;
+ ti.th = *tcp;
+ ti.th.th_seq = ntohl(ti.th.th_seq);
+ ti.th.th_ack = ntohl(ti.th.th_ack);
+ ti.ip6.ip6_nxt = IPPROTO_TCP;
+
+ if (ti.th.th_flags & TH_ACK) {
+ ack = 0;
+ seq = ti.th.th_ack;
+ flags = TH_RST;
+ } else {
+ ack = ti.th.th_seq;
+ if ((m->m_flags & M_PKTHDR) != 0) {
+ /*
+ * total new data to ACK is:
+ * total packet length,
+ * minus the header length,
+ * minus the tcp header length.
+ */
+ ack += m->m_pkthdr.len - hlen
+ - (ti.th.th_off << 2);
+ } else if (ip6->ip6_plen) {
+ ack += ntohs(ip6->ip6_plen) + sizeof(*ip6) -
+ hlen - (ti.th.th_off << 2);
+ } else {
+ m_freem(m);
+ return;
+ }
+ if (tcp->th_flags & TH_SYN)
+ ack++;
+ seq = 0;
+ flags = TH_RST|TH_ACK;
+ }
+ bcopy(&ti, ip6, sizeof(ti));
+ /*
+ * m is only used to recycle the mbuf
+ * The data in it is never read so we don't need
+ * to correct the offsets or anything
+ */
+ tcp_respond(NULL, ip6, tcp, m, ack, seq, flags);
+ } else if (code != ICMP6_UNREACH_RST) { /* 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
+ m_freem(m);
+
+ args->m = NULL;
+}
+
+#endif /* INET6 */
+
+static u_int64_t norule_counter; /* counter for ipfw_log(NULL...) */
+
+#define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
+#define SNP(buf) buf, sizeof(buf)
+
+/*
+ * We enter here when we have a rule with O_LOG.
+ * XXX this function alone takes about 2Kbytes of code!
+ */
+static void
+ipfw_log(struct ip_fw *f, u_int hlen, struct ip_fw_args *args,
+ struct mbuf *m, struct ifnet *oif, u_short offset, uint32_t tablearg,
+ struct ip *ip)
+{
+ struct ether_header *eh = args->eh;
+ char *action;
+ int limit_reached = 0;
+ char action2[40], proto[128], fragment[32];
+
+ fragment[0] = '\0';
+ proto[0] = '\0';
+
+ if (f == NULL) { /* bogus pkt */
+ if (verbose_limit != 0 && norule_counter >= verbose_limit)
+ return;
+ norule_counter++;
+ if (norule_counter == verbose_limit)
+ limit_reached = verbose_limit;
+ action = "Refuse";
+ } else { /* O_LOG is the first action, find the real one */
+ ipfw_insn *cmd = ACTION_PTR(f);
+ ipfw_insn_log *l = (ipfw_insn_log *)cmd;
+
+ if (l->max_log != 0 && l->log_left == 0)
+ return;
+ l->log_left--;
+ if (l->log_left == 0)
+ limit_reached = l->max_log;
+ cmd += F_LEN(cmd); /* point to first action */
+ if (cmd->opcode == O_ALTQ) {
+ ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
+
+ snprintf(SNPARGS(action2, 0), "Altq %d",
+ altq->qid);
+ cmd += F_LEN(cmd);
+ }
+ if (cmd->opcode == O_PROB)
+ cmd += F_LEN(cmd);
+
+ if (cmd->opcode == O_TAG)
+ cmd += F_LEN(cmd);
+
+ action = action2;
+ switch (cmd->opcode) {
+ case O_DENY:
+ action = "Deny";
+ break;
+
+ case O_REJECT:
+ if (cmd->arg1==ICMP_REJECT_RST)
+ action = "Reset";
+ else if (cmd->arg1==ICMP_UNREACH_HOST)
+ action = "Reject";
+ else
+ snprintf(SNPARGS(action2, 0), "Unreach %d",
+ cmd->arg1);
+ break;
+
+ case O_UNREACH6:
+ if (cmd->arg1==ICMP6_UNREACH_RST)
+ action = "Reset";
+ else
+ snprintf(SNPARGS(action2, 0), "Unreach %d",
+ cmd->arg1);
+ break;
+
+ case O_ACCEPT:
+ action = "Accept";
+ break;
+ case O_COUNT:
+ action = "Count";
+ break;
+ case O_DIVERT:
+ snprintf(SNPARGS(action2, 0), "Divert %d",
+ cmd->arg1);
+ break;
+ case O_TEE:
+ snprintf(SNPARGS(action2, 0), "Tee %d",
+ cmd->arg1);
+ break;
+ case O_SETFIB:
+ snprintf(SNPARGS(action2, 0), "SetFib %d",
+ cmd->arg1);
+ break;
+ case O_SKIPTO:
+ snprintf(SNPARGS(action2, 0), "SkipTo %d",
+ cmd->arg1);
+ break;
+ case O_PIPE:
+ snprintf(SNPARGS(action2, 0), "Pipe %d",
+ cmd->arg1);
+ break;
+ case O_QUEUE:
+ snprintf(SNPARGS(action2, 0), "Queue %d",
+ cmd->arg1);
+ break;
+ case O_FORWARD_IP: {
+ ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
+ int len;
+ struct in_addr dummyaddr;
+ if (sa->sa.sin_addr.s_addr == INADDR_ANY)
+ dummyaddr.s_addr = htonl(tablearg);
+ else
+ dummyaddr.s_addr = sa->sa.sin_addr.s_addr;
+
+ len = snprintf(SNPARGS(action2, 0), "Forward to %s",
+ inet_ntoa(dummyaddr));
+
+ if (sa->sa.sin_port)
+ snprintf(SNPARGS(action2, len), ":%d",
+ sa->sa.sin_port);
+ }
+ break;
+ case O_NETGRAPH:
+ snprintf(SNPARGS(action2, 0), "Netgraph %d",
+ cmd->arg1);
+ break;
+ case O_NGTEE:
+ snprintf(SNPARGS(action2, 0), "Ngtee %d",
+ cmd->arg1);
+ break;
+ case O_NAT:
+ action = "Nat";
+ break;
+ default:
+ action = "UNKNOWN";
+ break;
+ }
+ }
+
+ if (hlen == 0) { /* non-ip */
+ snprintf(SNPARGS(proto, 0), "MAC");
+
+ } else {
+ int len;
+ char src[48], dst[48];
+ struct icmphdr *icmp;
+ struct tcphdr *tcp;
+ struct udphdr *udp;
+#ifdef INET6
+ struct ip6_hdr *ip6 = NULL;
+ struct icmp6_hdr *icmp6;
+#endif
+ src[0] = '\0';
+ dst[0] = '\0';
+#ifdef INET6
+ if (IS_IP6_FLOW_ID(&(args->f_id))) {
+ char ip6buf[INET6_ADDRSTRLEN];
+ snprintf(src, sizeof(src), "[%s]",
+ ip6_sprintf(ip6buf, &args->f_id.src_ip6));
+ snprintf(dst, sizeof(dst), "[%s]",
+ ip6_sprintf(ip6buf, &args->f_id.dst_ip6));
+
+ ip6 = (struct ip6_hdr *)ip;
+ tcp = (struct tcphdr *)(((char *)ip) + hlen);
+ udp = (struct udphdr *)(((char *)ip) + hlen);
+ } else
+#endif
+ {
+ tcp = L3HDR(struct tcphdr, ip);
+ udp = L3HDR(struct udphdr, ip);
+
+ inet_ntoa_r(ip->ip_src, src);
+ inet_ntoa_r(ip->ip_dst, dst);
+ }
+
+ switch (args->f_id.proto) {
+ case IPPROTO_TCP:
+ len = snprintf(SNPARGS(proto, 0), "TCP %s", src);
+ if (offset == 0)
+ snprintf(SNPARGS(proto, len), ":%d %s:%d",
+ ntohs(tcp->th_sport),
+ dst,
+ ntohs(tcp->th_dport));
+ else
+ snprintf(SNPARGS(proto, len), " %s", dst);
+ break;
+
+ case IPPROTO_UDP:
+ len = snprintf(SNPARGS(proto, 0), "UDP %s", src);
+ if (offset == 0)
+ snprintf(SNPARGS(proto, len), ":%d %s:%d",
+ ntohs(udp->uh_sport),
+ dst,
+ ntohs(udp->uh_dport));
+ else
+ snprintf(SNPARGS(proto, len), " %s", dst);
+ break;
+
+ case IPPROTO_ICMP:
+ icmp = L3HDR(struct icmphdr, ip);
+ if (offset == 0)
+ len = snprintf(SNPARGS(proto, 0),
+ "ICMP:%u.%u ",
+ icmp->icmp_type, icmp->icmp_code);
+ else
+ len = snprintf(SNPARGS(proto, 0), "ICMP ");
+ len += snprintf(SNPARGS(proto, len), "%s", src);
+ snprintf(SNPARGS(proto, len), " %s", dst);
+ break;
+#ifdef INET6
+ case IPPROTO_ICMPV6:
+ icmp6 = (struct icmp6_hdr *)(((char *)ip) + hlen);
+ if (offset == 0)
+ len = snprintf(SNPARGS(proto, 0),
+ "ICMPv6:%u.%u ",
+ icmp6->icmp6_type, icmp6->icmp6_code);
+ else
+ len = snprintf(SNPARGS(proto, 0), "ICMPv6 ");
+ len += snprintf(SNPARGS(proto, len), "%s", src);
+ snprintf(SNPARGS(proto, len), " %s", dst);
+ break;
+#endif
+ default:
+ len = snprintf(SNPARGS(proto, 0), "P:%d %s",
+ args->f_id.proto, src);
+ snprintf(SNPARGS(proto, len), " %s", dst);
+ break;
+ }
+
+#ifdef INET6
+ if (IS_IP6_FLOW_ID(&(args->f_id))) {
+ if (offset & (IP6F_OFF_MASK | IP6F_MORE_FRAG))
+ snprintf(SNPARGS(fragment, 0),
+ " (frag %08x:%d@%d%s)",
+ args->f_id.frag_id6,
+ ntohs(ip6->ip6_plen) - hlen,
+ ntohs(offset & IP6F_OFF_MASK) << 3,
+ (offset & IP6F_MORE_FRAG) ? "+" : "");
+ } else
+#endif
+ {
+ int ip_off, ip_len;
+ if (1 || eh != NULL) { /* layer 2 packets are as on the wire */
+ ip_off = ntohs(ip->ip_off);
+ ip_len = ntohs(ip->ip_len);
+ } else {
+ ip_off = ip->ip_off;
+ ip_len = ip->ip_len;
+ }
+ if (ip_off & (IP_MF | IP_OFFMASK))
+ snprintf(SNPARGS(fragment, 0),
+ " (frag %d:%d@%d%s)",
+ ntohs(ip->ip_id), ip_len - (ip->ip_hl << 2),
+ offset << 3,
+ (ip_off & IP_MF) ? "+" : "");
+ }
+ }
+ if (oif || m->m_pkthdr.rcvif)
+ log(LOG_SECURITY | LOG_INFO,
+ "ipfw: %d %s %s %s via %s%s\n",
+ f ? f->rulenum : -1,
+ action, proto, oif ? "out" : "in",
+ oif ? oif->if_xname : m->m_pkthdr.rcvif->if_xname,
+ fragment);
+ else
+ log(LOG_SECURITY | LOG_INFO,
+ "ipfw: %d %s %s [no if info]%s\n",
+ f ? f->rulenum : -1,
+ action, proto, fragment);
+ if (limit_reached)
+ log(LOG_SECURITY | LOG_NOTICE,
+ "ipfw: limit %d reached on entry %d\n",
+ limit_reached, f ? f->rulenum : -1);
+}
+
+/*
+ * IMPORTANT: the hash function for dynamic rules must be commutative
+ * in source and destination (ip,port), because rules are bidirectional
+ * and we want to find both in the same bucket.
+ */
+static __inline int
+hash_packet(struct ipfw_flow_id *id)
+{
+ u_int32_t i;
+
+#ifdef INET6
+ if (IS_IP6_FLOW_ID(id))
+ i = hash_packet6(id);
+ else
+#endif /* INET6 */
+ i = (id->dst_ip) ^ (id->src_ip) ^ (id->dst_port) ^ (id->src_port);
+ i &= (curr_dyn_buckets - 1);
+ return i;
+}
+
+/**
+ * unlink a dynamic rule from a chain. prev is a pointer to
+ * the previous one, q is a pointer to the rule to delete,
+ * head is a pointer to the head of the queue.
+ * Modifies q and potentially also head.
+ */
+#define UNLINK_DYN_RULE(prev, head, q) { \
+ ipfw_dyn_rule *old_q = q; \
+ \
+ /* remove a refcount to the parent */ \
+ if (q->dyn_type == O_LIMIT) \
+ q->parent->count--; \
+ DEB(printf("ipfw: unlink entry 0x%08x %d -> 0x%08x %d, %d left\n",\
+ (q->id.src_ip), (q->id.src_port), \
+ (q->id.dst_ip), (q->id.dst_port), dyn_count-1 ); ) \
+ if (prev != NULL) \
+ prev->next = q = q->next; \
+ else \
+ head = q = q->next; \
+ dyn_count--; \
+ uma_zfree(ipfw_dyn_rule_zone, old_q); }
+
+#define TIME_LEQ(a,b) ((int)((a)-(b)) <= 0)
+
+/**
+ * Remove dynamic rules pointing to "rule", or all of them if rule == NULL.
+ *
+ * If keep_me == NULL, rules are deleted even if not expired,
+ * otherwise only expired rules are removed.
+ *
+ * The value of the second parameter is also used to point to identify
+ * a rule we absolutely do not want to remove (e.g. because we are
+ * holding a reference to it -- this is the case with O_LIMIT_PARENT
+ * rules). The pointer is only used for comparison, so any non-null
+ * value will do.
+ */
+static void
+remove_dyn_rule(struct ip_fw *rule, ipfw_dyn_rule *keep_me)
+{
+ static u_int32_t last_remove = 0;
+
+#define FORCE (keep_me == NULL)
+
+ ipfw_dyn_rule *prev, *q;
+ int i, pass = 0, max_pass = 0;
+
+ IPFW_DYN_LOCK_ASSERT();
+
+ if (ipfw_dyn_v == NULL || dyn_count == 0)
+ return;
+ /* do not expire more than once per second, it is useless */
+ if (!FORCE && last_remove == time_uptime)
+ return;
+ last_remove = time_uptime;
+
+ /*
+ * because O_LIMIT refer to parent rules, during the first pass only
+ * remove child and mark any pending LIMIT_PARENT, and remove
+ * them in a second pass.
+ */
+next_pass:
+ for (i = 0 ; i < curr_dyn_buckets ; i++) {
+ for (prev=NULL, q = ipfw_dyn_v[i] ; q ; ) {
+ /*
+ * Logic can become complex here, so we split tests.
+ */
+ if (q == keep_me)
+ goto next;
+ if (rule != NULL && rule != q->rule)
+ goto next; /* not the one we are looking for */
+ if (q->dyn_type == O_LIMIT_PARENT) {
+ /*
+ * handle parent in the second pass,
+ * record we need one.
+ */
+ max_pass = 1;
+ if (pass == 0)
+ goto next;
+ if (FORCE && q->count != 0 ) {
+ /* XXX should not happen! */
+ printf("ipfw: OUCH! cannot remove rule,"
+ " count %d\n", q->count);
+ }
+ } else {
+ if (!FORCE &&
+ !TIME_LEQ( q->expire, time_uptime ))
+ goto next;
+ }
+ if (q->dyn_type != O_LIMIT_PARENT || !q->count) {
+ UNLINK_DYN_RULE(prev, ipfw_dyn_v[i], q);
+ continue;
+ }
+next:
+ prev=q;
+ q=q->next;
+ }
+ }
+ if (pass++ < max_pass)
+ goto next_pass;
+}
+
+
+/**
+ * lookup a dynamic rule.
+ */
+static ipfw_dyn_rule *
+lookup_dyn_rule_locked(struct ipfw_flow_id *pkt, int *match_direction,
+ struct tcphdr *tcp)
+{
+ /*
+ * stateful ipfw extensions.
+ * Lookup into dynamic session queue
+ */
+#define MATCH_REVERSE 0
+#define MATCH_FORWARD 1
+#define MATCH_NONE 2
+#define MATCH_UNKNOWN 3
+ int i, dir = MATCH_NONE;
+ ipfw_dyn_rule *prev, *q=NULL;
+
+ IPFW_DYN_LOCK_ASSERT();
+
+ if (ipfw_dyn_v == NULL)
+ goto done; /* not found */
+ i = hash_packet( pkt );
+ for (prev=NULL, q = ipfw_dyn_v[i] ; q != NULL ; ) {
+ if (q->dyn_type == O_LIMIT_PARENT && q->count)
+ goto next;
+ if (TIME_LEQ( q->expire, time_uptime)) { /* expire entry */
+ UNLINK_DYN_RULE(prev, ipfw_dyn_v[i], q);
+ continue;
+ }
+ if (pkt->proto == q->id.proto &&
+ q->dyn_type != O_LIMIT_PARENT) {
+ if (IS_IP6_FLOW_ID(pkt)) {
+ if (IN6_ARE_ADDR_EQUAL(&(pkt->src_ip6),
+ &(q->id.src_ip6)) &&
+ IN6_ARE_ADDR_EQUAL(&(pkt->dst_ip6),
+ &(q->id.dst_ip6)) &&
+ pkt->src_port == q->id.src_port &&
+ pkt->dst_port == q->id.dst_port ) {
+ dir = MATCH_FORWARD;
+ break;
+ }
+ if (IN6_ARE_ADDR_EQUAL(&(pkt->src_ip6),
+ &(q->id.dst_ip6)) &&
+ IN6_ARE_ADDR_EQUAL(&(pkt->dst_ip6),
+ &(q->id.src_ip6)) &&
+ pkt->src_port == q->id.dst_port &&
+ pkt->dst_port == q->id.src_port ) {
+ dir = MATCH_REVERSE;
+ break;
+ }
+ } else {
+ if (pkt->src_ip == q->id.src_ip &&
+ pkt->dst_ip == q->id.dst_ip &&
+ pkt->src_port == q->id.src_port &&
+ pkt->dst_port == q->id.dst_port ) {
+ dir = MATCH_FORWARD;
+ break;
+ }
+ if (pkt->src_ip == q->id.dst_ip &&
+ pkt->dst_ip == q->id.src_ip &&
+ pkt->src_port == q->id.dst_port &&
+ pkt->dst_port == q->id.src_port ) {
+ dir = MATCH_REVERSE;
+ break;
+ }
+ }
+ }
+next:
+ prev = q;
+ q = q->next;
+ }
+ if (q == NULL)
+ goto done; /* q = NULL, not found */
+
+ if ( prev != NULL) { /* found and not in front */
+ prev->next = q->next;
+ q->next = ipfw_dyn_v[i];
+ ipfw_dyn_v[i] = q;
+ }
+ if (pkt->proto == IPPROTO_TCP) { /* update state according to flags */
+ u_char flags = pkt->flags & (TH_FIN|TH_SYN|TH_RST);
+
+#define BOTH_SYN (TH_SYN | (TH_SYN << 8))
+#define BOTH_FIN (TH_FIN | (TH_FIN << 8))
+ q->state |= (dir == MATCH_FORWARD ) ? flags : (flags << 8);
+ switch (q->state) {
+ case TH_SYN: /* opening */
+ q->expire = time_uptime + dyn_syn_lifetime;
+ break;
+
+ case BOTH_SYN: /* move to established */
+ case BOTH_SYN | TH_FIN : /* one side tries to close */
+ case BOTH_SYN | (TH_FIN << 8) :
+ if (tcp) {
+#define _SEQ_GE(a,b) ((int)(a) - (int)(b) >= 0)
+ u_int32_t ack = ntohl(tcp->th_ack);
+ if (dir == MATCH_FORWARD) {
+ if (q->ack_fwd == 0 || _SEQ_GE(ack, q->ack_fwd))
+ q->ack_fwd = ack;
+ else { /* ignore out-of-sequence */
+ break;
+ }
+ } else {
+ if (q->ack_rev == 0 || _SEQ_GE(ack, q->ack_rev))
+ q->ack_rev = ack;
+ else { /* ignore out-of-sequence */
+ break;
+ }
+ }
+ }
+ q->expire = time_uptime + dyn_ack_lifetime;
+ break;
+
+ case BOTH_SYN | BOTH_FIN: /* both sides closed */
+ if (dyn_fin_lifetime >= dyn_keepalive_period)
+ dyn_fin_lifetime = dyn_keepalive_period - 1;
+ q->expire = time_uptime + dyn_fin_lifetime;
+ break;
+
+ default:
+#if 0
+ /*
+ * reset or some invalid combination, but can also
+ * occur if we use keep-state the wrong way.
+ */
+ if ( (q->state & ((TH_RST << 8)|TH_RST)) == 0)
+ printf("invalid state: 0x%x\n", q->state);
+#endif
+ if (dyn_rst_lifetime >= dyn_keepalive_period)
+ dyn_rst_lifetime = dyn_keepalive_period - 1;
+ q->expire = time_uptime + dyn_rst_lifetime;
+ break;
+ }
+ } else if (pkt->proto == IPPROTO_UDP) {
+ q->expire = time_uptime + dyn_udp_lifetime;
+ } else {
+ /* other protocols */
+ q->expire = time_uptime + dyn_short_lifetime;
+ }
+done:
+ if (match_direction)
+ *match_direction = dir;
+ return q;
+}
+
+static ipfw_dyn_rule *
+lookup_dyn_rule(struct ipfw_flow_id *pkt, int *match_direction,
+ struct tcphdr *tcp)
+{
+ ipfw_dyn_rule *q;
+
+ IPFW_DYN_LOCK();
+ q = lookup_dyn_rule_locked(pkt, match_direction, tcp);
+ if (q == NULL)
+ IPFW_DYN_UNLOCK();
+ /* NB: return table locked when q is not NULL */
+ return q;
+}
+
+static void
+realloc_dynamic_table(void)
+{
+ IPFW_DYN_LOCK_ASSERT();
+
+ /*
+ * Try reallocation, make sure we have a power of 2 and do
+ * not allow more than 64k entries. In case of overflow,
+ * default to 1024.
+ */
+
+ if (dyn_buckets > 65536)
+ dyn_buckets = 1024;
+ if ((dyn_buckets & (dyn_buckets-1)) != 0) { /* not a power of 2 */
+ dyn_buckets = curr_dyn_buckets; /* reset */
+ return;
+ }
+ curr_dyn_buckets = dyn_buckets;
+ if (ipfw_dyn_v != NULL)
+ free(ipfw_dyn_v, M_IPFW);
+ for (;;) {
+ ipfw_dyn_v = malloc(curr_dyn_buckets * sizeof(ipfw_dyn_rule *),
+ M_IPFW, M_NOWAIT | M_ZERO);
+ if (ipfw_dyn_v != NULL || curr_dyn_buckets <= 2)
+ break;
+ curr_dyn_buckets /= 2;
+ }
+}
+
+/**
+ * Install state of type 'type' for a dynamic session.
+ * The hash table contains two type of rules:
+ * - regular rules (O_KEEP_STATE)
+ * - rules for sessions with limited number of sess per user
+ * (O_LIMIT). When they are created, the parent is
+ * increased by 1, and decreased on delete. In this case,
+ * the third parameter is the parent rule and not the chain.
+ * - "parent" rules for the above (O_LIMIT_PARENT).
+ */
+static ipfw_dyn_rule *
+add_dyn_rule(struct ipfw_flow_id *id, u_int8_t dyn_type, struct ip_fw *rule)
+{
+ ipfw_dyn_rule *r;
+ int i;
+
+ IPFW_DYN_LOCK_ASSERT();
+
+ if (ipfw_dyn_v == NULL ||
+ (dyn_count == 0 && dyn_buckets != curr_dyn_buckets)) {
+ realloc_dynamic_table();
+ if (ipfw_dyn_v == NULL)
+ return NULL; /* failed ! */
+ }
+ i = hash_packet(id);
+
+ r = uma_zalloc(ipfw_dyn_rule_zone, M_NOWAIT | M_ZERO);
+ if (r == NULL) {
+ printf ("ipfw: sorry cannot allocate state\n");
+ return NULL;
+ }
+
+ /* increase refcount on parent, and set pointer */
+ if (dyn_type == O_LIMIT) {
+ ipfw_dyn_rule *parent = (ipfw_dyn_rule *)rule;
+ if ( parent->dyn_type != O_LIMIT_PARENT)
+ panic("invalid parent");
+ parent->count++;
+ r->parent = parent;
+ rule = parent->rule;
+ }
+
+ r->id = *id;
+ r->expire = time_uptime + dyn_syn_lifetime;
+ r->rule = rule;
+ r->dyn_type = dyn_type;
+ r->pcnt = r->bcnt = 0;
+ r->count = 0;
+
+ r->bucket = i;
+ r->next = ipfw_dyn_v[i];
+ ipfw_dyn_v[i] = r;
+ dyn_count++;
+ DEB(printf("ipfw: add dyn entry ty %d 0x%08x %d -> 0x%08x %d, total %d\n",
+ dyn_type,
+ (r->id.src_ip), (r->id.src_port),
+ (r->id.dst_ip), (r->id.dst_port),
+ dyn_count ); )
+ return r;
+}
+
+/**
+ * lookup dynamic parent rule using pkt and rule as search keys.
+ * If the lookup fails, then install one.
+ */
+static ipfw_dyn_rule *
+lookup_dyn_parent(struct ipfw_flow_id *pkt, struct ip_fw *rule)
+{
+ ipfw_dyn_rule *q;
+ int i;
+
+ IPFW_DYN_LOCK_ASSERT();
+
+ if (ipfw_dyn_v) {
+ int is_v6 = IS_IP6_FLOW_ID(pkt);
+ i = hash_packet( pkt );
+ for (q = ipfw_dyn_v[i] ; q != NULL ; q=q->next)
+ if (q->dyn_type == O_LIMIT_PARENT &&
+ rule== q->rule &&
+ pkt->proto == q->id.proto &&
+ pkt->src_port == q->id.src_port &&
+ pkt->dst_port == q->id.dst_port &&
+ (
+ (is_v6 &&
+ IN6_ARE_ADDR_EQUAL(&(pkt->src_ip6),
+ &(q->id.src_ip6)) &&
+ IN6_ARE_ADDR_EQUAL(&(pkt->dst_ip6),
+ &(q->id.dst_ip6))) ||
+ (!is_v6 &&
+ pkt->src_ip == q->id.src_ip &&
+ pkt->dst_ip == q->id.dst_ip)
+ )
+ ) {
+ q->expire = time_uptime + dyn_short_lifetime;
+ DEB(printf("ipfw: lookup_dyn_parent found 0x%p\n",q);)
+ return q;
+ }
+ }
+ return add_dyn_rule(pkt, O_LIMIT_PARENT, rule);
+}
+
+/**
+ * Install dynamic state for rule type cmd->o.opcode
+ *
+ * Returns 1 (failure) if state is not installed because of errors or because
+ * session limitations are enforced.
+ */
+static int
+install_state(struct ip_fw *rule, ipfw_insn_limit *cmd,
+ struct ip_fw_args *args, uint32_t tablearg)
+{
+ static int last_log;
+ ipfw_dyn_rule *q;
+ struct in_addr da;
+ char src[48], dst[48];
+
+ src[0] = '\0';
+ dst[0] = '\0';
+
+ DEB(
+ printf("ipfw: %s: type %d 0x%08x %u -> 0x%08x %u\n",
+ __func__, cmd->o.opcode,
+ (args->f_id.src_ip), (args->f_id.src_port),
+ (args->f_id.dst_ip), (args->f_id.dst_port));
+ )
+
+ IPFW_DYN_LOCK();
+
+ q = lookup_dyn_rule_locked(&args->f_id, NULL, NULL);
+
+ if (q != NULL) { /* should never occur */
+ if (last_log != time_uptime) {
+ last_log = time_uptime;
+ printf("ipfw: %s: entry already present, done\n",
+ __func__);
+ }
+ IPFW_DYN_UNLOCK();
+ return (0);
+ }
+
+ if (dyn_count >= dyn_max)
+ /* Run out of slots, try to remove any expired rule. */
+ remove_dyn_rule(NULL, (ipfw_dyn_rule *)1);
+
+ if (dyn_count >= dyn_max) {
+ if (last_log != time_uptime) {
+ last_log = time_uptime;
+ printf("ipfw: %s: Too many dynamic rules\n", __func__);
+ }
+ IPFW_DYN_UNLOCK();
+ return (1); /* cannot install, notify caller */
+ }
+
+ switch (cmd->o.opcode) {
+ case O_KEEP_STATE: /* bidir rule */
+ add_dyn_rule(&args->f_id, O_KEEP_STATE, rule);
+ break;
+
+ case O_LIMIT: { /* limit number of sessions */
+ struct ipfw_flow_id id;
+ ipfw_dyn_rule *parent;
+ uint32_t conn_limit;
+ uint16_t limit_mask = cmd->limit_mask;
+
+ conn_limit = (cmd->conn_limit == IP_FW_TABLEARG) ?
+ tablearg : cmd->conn_limit;
+
+ DEB(
+ if (cmd->conn_limit == IP_FW_TABLEARG)
+ printf("ipfw: %s: O_LIMIT rule, conn_limit: %u "
+ "(tablearg)\n", __func__, conn_limit);
+ else
+ printf("ipfw: %s: O_LIMIT rule, conn_limit: %u\n",
+ __func__, conn_limit);
+ )
+
+ id.dst_ip = id.src_ip = id.dst_port = id.src_port = 0;
+ id.proto = args->f_id.proto;
+ id.addr_type = args->f_id.addr_type;
+ id.fib = M_GETFIB(args->m);
+
+ if (IS_IP6_FLOW_ID (&(args->f_id))) {
+ if (limit_mask & DYN_SRC_ADDR)
+ id.src_ip6 = args->f_id.src_ip6;
+ if (limit_mask & DYN_DST_ADDR)
+ id.dst_ip6 = args->f_id.dst_ip6;
+ } else {
+ if (limit_mask & DYN_SRC_ADDR)
+ id.src_ip = args->f_id.src_ip;
+ if (limit_mask & DYN_DST_ADDR)
+ id.dst_ip = args->f_id.dst_ip;
+ }
+ if (limit_mask & DYN_SRC_PORT)
+ id.src_port = args->f_id.src_port;
+ if (limit_mask & DYN_DST_PORT)
+ id.dst_port = args->f_id.dst_port;
+ if ((parent = lookup_dyn_parent(&id, rule)) == NULL) {
+ printf("ipfw: %s: add parent failed\n", __func__);
+ IPFW_DYN_UNLOCK();
+ return (1);
+ }
+
+ if (parent->count >= conn_limit) {
+ /* See if we can remove some expired rule. */
+ remove_dyn_rule(rule, parent);
+ if (parent->count >= conn_limit) {
+ if (fw_verbose && last_log != time_uptime) {
+ last_log = time_uptime;
+#ifdef INET6
+ /*
+ * XXX IPv6 flows are not
+ * supported yet.
+ */
+ if (IS_IP6_FLOW_ID(&(args->f_id))) {
+ char ip6buf[INET6_ADDRSTRLEN];
+ snprintf(src, sizeof(src),
+ "[%s]", ip6_sprintf(ip6buf,
+ &args->f_id.src_ip6));
+ snprintf(dst, sizeof(dst),
+ "[%s]", ip6_sprintf(ip6buf,
+ &args->f_id.dst_ip6));
+ } else
+#endif
+ {
+ da.s_addr =
+ htonl(args->f_id.src_ip);
+ inet_ntoa_r(da, src);
+ da.s_addr =
+ htonl(args->f_id.dst_ip);
+ inet_ntoa_r(da, dst);
+ }
+ log(LOG_SECURITY | LOG_DEBUG,
+ "ipfw: %d %s %s:%u -> %s:%u, %s\n",
+ parent->rule->rulenum,
+ "drop session",
+ src, (args->f_id.src_port),
+ dst, (args->f_id.dst_port),
+ "too many entries");
+ }
+ IPFW_DYN_UNLOCK();
+ return (1);
+ }
+ }
+ add_dyn_rule(&args->f_id, O_LIMIT, (struct ip_fw *)parent);
+ break;
+ }
+ default:
+ printf("ipfw: %s: unknown dynamic rule type %u\n",
+ __func__, cmd->o.opcode);
+ IPFW_DYN_UNLOCK();
+ return (1);
+ }
+
+ /* XXX just set lifetime */
+ lookup_dyn_rule_locked(&args->f_id, NULL, NULL);
+
+ IPFW_DYN_UNLOCK();
+ return (0);
+}
+
+/*
+ * 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.
+ */
+static struct mbuf *
+send_pkt(struct mbuf *replyto, struct ipfw_flow_id *id, u_int32_t seq,
+ u_int32_t ack, int flags)
+{
+#if defined( __linux__ ) || defined( _WIN32 )
+ return NULL;
+#else
+ struct mbuf *m;
+ struct ip *ip;
+ struct tcphdr *tcp;
+
+ MGETHDR(m, M_DONTWAIT, MT_DATA);
+ if (m == 0)
+ return (NULL);
+ m->m_pkthdr.rcvif = (struct ifnet *)0;
+
+ M_SETFIB(m, id->fib);
+#ifdef MAC
+ if (replyto != NULL)
+ mac_create_mbuf_netlayer(replyto, m);
+ else
+ mac_create_mbuf_from_firewall(m);
+#else
+ (void)replyto; /* don't warn about unused arg */
+#endif
+
+ m->m_pkthdr.len = m->m_len = sizeof(struct ip) + sizeof(struct tcphdr);
+ m->m_data += max_linkhdr;
+
+ ip = mtod(m, struct ip *);
+ bzero(ip, m->m_len);
+ tcp = (struct tcphdr *)(ip + 1); /* no IP options */
+ ip->ip_p = IPPROTO_TCP;
+ tcp->th_off = 5;
+ /*
+ * Assume we are sending a RST (or a keepalive in the reverse
+ * direction), swap src and destination addresses and ports.
+ */
+ ip->ip_src.s_addr = htonl(id->dst_ip);
+ ip->ip_dst.s_addr = htonl(id->src_ip);
+ tcp->th_sport = htons(id->dst_port);
+ tcp->th_dport = htons(id->src_port);
+ if (flags & TH_RST) { /* we are sending a RST */
+ if (flags & TH_ACK) {
+ tcp->th_seq = htonl(ack);
+ tcp->th_ack = htonl(0);
+ tcp->th_flags = TH_RST;
+ } else {
+ if (flags & TH_SYN)
+ seq++;
+ tcp->th_seq = htonl(0);
+ tcp->th_ack = htonl(seq);
+ tcp->th_flags = TH_RST | TH_ACK;
+ }
+ } else {
+ /*
+ * We are sending a keepalive. flags & TH_SYN determines
+ * the direction, forward if set, reverse if clear.
+ * NOTE: seq and ack are always assumed to be correct
+ * as set by the caller. This may be confusing...
+ */
+ if (flags & TH_SYN) {
+ /*
+ * we have to rewrite the correct addresses!
+ */
+ ip->ip_dst.s_addr = htonl(id->dst_ip);
+ ip->ip_src.s_addr = htonl(id->src_ip);
+ tcp->th_dport = htons(id->dst_port);
+ tcp->th_sport = htons(id->src_port);
+ }
+ tcp->th_seq = htonl(seq);
+ tcp->th_ack = htonl(ack);
+ tcp->th_flags = TH_ACK;
+ }
+ /*
+ * set ip_len to the payload size so we can compute
+ * the tcp checksum on the pseudoheader
+ * XXX check this, could save a couple of words ?
+ */
+ ip->ip_len = htons(sizeof(struct tcphdr));
+ tcp->th_sum = in_cksum(m, m->m_pkthdr.len);
+ /*
+ * now fill fields left out earlier
+ */
+ ip->ip_ttl = ip_defttl;
+ ip->ip_len = m->m_pkthdr.len;
+ m->m_flags |= M_SKIP_FIREWALL;
+ return (m);
+#endif /* !__linux__ */
+}
+
+/*
+ * sends a reject message, consuming the mbuf passed as an argument.
+ */
+static void
+send_reject(struct ip_fw_args *args, int code, int ip_len, struct ip *ip)
+{
+
+#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) { /* Send an ICMP unreach */
+ /* We need the IP header in host order for icmp_error(). */
+#if !defined( __linux__ ) && !defined( _WIN32 )
+ if (args->eh != NULL) {
+ ip->ip_len = ntohs(ip->ip_len);
+ ip->ip_off = ntohs(ip->ip_off);
+ }
+#endif
+ icmp_error(args->m, ICMP_UNREACH, code, 0L, 0);
+ } else if (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 = 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);
+ }
+ m_freem(args->m);
+ } else
+ m_freem(args->m);
+ args->m = NULL;
+}
+
+/**
+ *
+ * Given an ip_fw *, lookup_next_rule will return a pointer
+ * to the next rule, which can be either the jump
+ * target (for skipto instructions) or the next one in the list (in
+ * all other cases including a missing jump target).
+ * The result is also written in the "next_rule" field of the rule.
+ * Backward jumps are not allowed, so start looking from the next
+ * rule...
+ *
+ * This never returns NULL -- in case we do not have an exact match,
+ * the next rule is returned. When the ruleset is changed,
+ * pointers are flushed so we are always correct.
+ */
+
+static struct ip_fw *
+lookup_next_rule(struct ip_fw *me, u_int32_t tablearg)
+{
+ struct ip_fw *rule = NULL;
+ ipfw_insn *cmd;
+ u_int16_t rulenum;
+
+ /* look for action, in case it is a skipto */
+ cmd = ACTION_PTR(me);
+ if (cmd->opcode == O_LOG)
+ cmd += F_LEN(cmd);
+ if (cmd->opcode == O_ALTQ)
+ cmd += F_LEN(cmd);
+ if (cmd->opcode == O_TAG)
+ cmd += F_LEN(cmd);
+ if (cmd->opcode == O_SKIPTO ) {
+ if (tablearg != 0) {
+ rulenum = (u_int16_t)tablearg;
+ } else {
+ rulenum = cmd->arg1;
+ }
+ for (rule = me->next; rule ; rule = rule->next) {
+ if (rule->rulenum >= rulenum) {
+ break;
+ }
+ }
+ }
+ if (rule == NULL) /* failure or not a skipto */
+ rule = me->next;
+ me->next_rule = rule;
+ return rule;
+}
+
+#ifdef radix
+static int
+add_table_entry(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
+ uint8_t mlen, uint32_t value)
+{
+ struct radix_node_head *rnh;
+ struct table_entry *ent;
+ struct radix_node *rn;
+
+ if (tbl >= IPFW_TABLES_MAX)
+ return (EINVAL);
+ rnh = ch->tables[tbl];
+ ent = malloc(sizeof(*ent), M_IPFW_TBL, M_NOWAIT | M_ZERO);
+ if (ent == NULL)
+ return (ENOMEM);
+ ent->value = value;
+ ent->addr.sin_len = ent->mask.sin_len = 8;
+ ent->mask.sin_addr.s_addr = htonl(mlen ? ~((1 << (32 - mlen)) - 1) : 0);
+ ent->addr.sin_addr.s_addr = addr & ent->mask.sin_addr.s_addr;
+ IPFW_WLOCK(ch);
+ rn = rnh->rnh_addaddr(&ent->addr, &ent->mask, rnh, (void *)ent);
+ if (rn == NULL) {
+ IPFW_WUNLOCK(ch);
+ free(ent, M_IPFW_TBL);
+ return (EEXIST);
+ }
+ IPFW_WUNLOCK(ch);
+ return (0);
+}
+
+static int
+del_table_entry(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
+ uint8_t mlen)
+{
+ struct radix_node_head *rnh;
+ struct table_entry *ent;
+ struct sockaddr_in sa, mask;
+
+ if (tbl >= IPFW_TABLES_MAX)
+ return (EINVAL);
+ rnh = ch->tables[tbl];
+ sa.sin_len = mask.sin_len = 8;
+ mask.sin_addr.s_addr = htonl(mlen ? ~((1 << (32 - mlen)) - 1) : 0);
+ sa.sin_addr.s_addr = addr & mask.sin_addr.s_addr;
+ IPFW_WLOCK(ch);
+ ent = (struct table_entry *)rnh->rnh_deladdr(&sa, &mask, rnh);
+ if (ent == NULL) {
+ IPFW_WUNLOCK(ch);
+ return (ESRCH);
+ }
+ IPFW_WUNLOCK(ch);
+ free(ent, M_IPFW_TBL);
+ return (0);
+}
+
+static int
+flush_table_entry(struct radix_node *rn, void *arg)
+{
+ struct radix_node_head * const rnh = arg;
+ struct table_entry *ent;
+
+ ent = (struct table_entry *)
+ rnh->rnh_deladdr(rn->rn_key, rn->rn_mask, rnh);
+ if (ent != NULL)
+ free(ent, M_IPFW_TBL);
+ return (0);
+}
+
+static int
+flush_table(struct ip_fw_chain *ch, uint16_t tbl)
+{
+ struct radix_node_head *rnh;
+
+ IPFW_WLOCK_ASSERT(ch);
+
+ if (tbl >= IPFW_TABLES_MAX)
+ return (EINVAL);
+ rnh = ch->tables[tbl];
+ KASSERT(rnh != NULL, ("NULL IPFW table"));
+ rnh->rnh_walktree(rnh, flush_table_entry, rnh);
+ return (0);
+}
+#endif
+
+static void
+flush_tables(struct ip_fw_chain *ch)
+{
+#ifdef radix
+ uint16_t tbl;
+
+ IPFW_WLOCK_ASSERT(ch);
+
+ for (tbl = 0; tbl < IPFW_TABLES_MAX; tbl++)
+ flush_table(ch, tbl);
+#endif
+}
+
+static int
+init_tables(struct ip_fw_chain *ch)
+{
+#ifdef radix
+ int i;
+ uint16_t j;
+
+ for (i = 0; i < IPFW_TABLES_MAX; i++) {
+ if (!rn_inithead((void **)&ch->tables[i], 32)) {
+ for (j = 0; j < i; j++) {
+ (void) flush_table(ch, j);
+ }
+ return (ENOMEM);
+ }
+ }
+#endif
+ return (0);
+}
+
+static int
+lookup_table(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
+ uint32_t *val)
+{
+#ifdef radix
+ struct radix_node_head *rnh;
+ struct table_entry *ent;
+ struct sockaddr_in sa;
+
+ if (tbl >= IPFW_TABLES_MAX)
+ return (0);
+ rnh = ch->tables[tbl];
+ sa.sin_len = 8;
+ sa.sin_addr.s_addr = addr;
+ ent = (struct table_entry *)(rnh->rnh_lookup(&sa, NULL, rnh));
+ if (ent != NULL) {
+ *val = ent->value;
+ return (1);
+ }
+#endif
+ return (0);
+}
+
+#ifdef radix
+static int
+count_table_entry(struct radix_node *rn, void *arg)
+{
+ u_int32_t * const cnt = arg;
+
+ (*cnt)++;
+ return (0);
+}
+
+static int
+count_table(struct ip_fw_chain *ch, uint32_t tbl, uint32_t *cnt)
+{
+ struct radix_node_head *rnh;
+
+ if (tbl >= IPFW_TABLES_MAX)
+ return (EINVAL);
+ rnh = ch->tables[tbl];
+ *cnt = 0;
+ rnh->rnh_walktree(rnh, count_table_entry, cnt);
+ return (0);
+}
+
+static int
+dump_table_entry(struct radix_node *rn, void *arg)
+{
+ struct table_entry * const n = (struct table_entry *)rn;
+ ipfw_table * const tbl = arg;
+ ipfw_table_entry *ent;
+
+ if (tbl->cnt == tbl->size)
+ return (1);
+ ent = &tbl->ent[tbl->cnt];
+ ent->tbl = tbl->tbl;
+ if (in_nullhost(n->mask.sin_addr))
+ ent->masklen = 0;
+ else
+ ent->masklen = 33 - ffs(ntohl(n->mask.sin_addr.s_addr));
+ ent->addr = n->addr.sin_addr.s_addr;
+ ent->value = n->value;
+ tbl->cnt++;
+ return (0);
+}
+
+static int
+dump_table(struct ip_fw_chain *ch, ipfw_table *tbl)
+{
+ struct radix_node_head *rnh;
+
+ if (tbl->tbl >= IPFW_TABLES_MAX)
+ return (EINVAL);
+ rnh = ch->tables[tbl->tbl];
+ tbl->cnt = 0;
+ rnh->rnh_walktree(rnh, dump_table_entry, tbl);
+ return (0);
+}
+#endif
+
+#if 0
+static void
+fill_ugid_cache(struct inpcb *inp, struct ip_fw_ugid *ugp)
+{
+ struct ucred *cr;
+
+ cr = inp->inp_cred;
+ ugp->fw_prid = jailed(cr) ? cr->cr_prison->pr_id : -1;
+ ugp->fw_uid = cr->cr_uid;
+ ugp->fw_ngroups = cr->cr_ngroups;
+ bcopy(cr->cr_groups, ugp->fw_groups, sizeof(ugp->fw_groups));
+}
+#endif /* no uigid support */
+
+static int
+check_uidgid(ipfw_insn_u32 *insn, int proto, struct ifnet *oif,
+ struct in_addr dst_ip, u_int16_t dst_port, struct in_addr src_ip,
+ u_int16_t src_port, struct ip_fw_ugid *ugp, int *ugid_lookupp,
+ struct inpcb *inp)
+{
+#if 1
+ return 0;
+#else
+ struct inpcbinfo *pi;
+ int wildcard;
+ struct inpcb *pcb;
+ int match;
+ gid_t *gp;
+
+ /*
+ * 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) {
+ fill_ugid_cache(inp, ugp);
+ *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 (proto == IPPROTO_TCP) {
+ wildcard = 0;
+ pi = &tcbinfo;
+ } else if (proto == IPPROTO_UDP) {
+ wildcard = INPLOOKUP_WILDCARD;
+ pi = &udbinfo;
+ } else
+ return 0;
+ match = 0;
+ if (*ugid_lookupp == 0) {
+ INP_INFO_RLOCK(pi);
+ pcb = (oif) ?
+ in_pcblookup_hash(pi,
+ dst_ip, htons(dst_port),
+ src_ip, htons(src_port),
+ wildcard, oif) :
+ in_pcblookup_hash(pi,
+ src_ip, htons(src_port),
+ dst_ip, htons(dst_port),
+ wildcard, NULL);
+ if (pcb != NULL) {
+ fill_ugid_cache(pcb, ugp);
+ *ugid_lookupp = 1;
+ }
+ INP_INFO_RUNLOCK(pi);
+ if (*ugid_lookupp == 0) {
+ /*
+ * If the lookup did not yield any results, there
+ * is no sense in coming back and trying again. So
+ * we can set lookup to -1 and ensure that we wont
+ * bother the pcb system again.
+ */
+ *ugid_lookupp = -1;
+ return (0);
+ }
+ }
+ if (insn->o.opcode == O_UID)
+ match = (ugp->fw_uid == (uid_t)insn->d[0]);
+ else if (insn->o.opcode == O_GID) {
+ for (gp = ugp->fw_groups;
+ gp < &ugp->fw_groups[ugp->fw_ngroups]; gp++)
+ if (*gp == (gid_t)insn->d[0]) {
+ match = 1;
+ break;
+ }
+ } else if (insn->o.opcode == O_JAIL)
+ match = (ugp->fw_prid == (int)insn->d[0]);
+ return match;
+#endif
+}
+
+/*
+ * 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->eh (in) Mac header if present, or NULL for layer3 packet.
+ * args->L3offset Number of bytes bypassed if we came from L2.
+ * e.g. often sizeof(eh) ** NOTYET **
+ * args->oif Outgoing interface, or NULL if packet is incoming.
+ * The incoming interface is in the mbuf. (in)
+ * 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->f_id Addresses grabbed from the packet (out)
+ * args->cookie 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
+ *
+ */
+int
+ipfw_chk(struct ip_fw_args *args)
+{
+ /*
+ * Local variables holding state during the processing of 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.
+ *
+ * args->eh The MAC header. It is non-null for a layer2
+ * packet, it is NULL for a layer-3 packet.
+ * **notyet**
+ * args->L3offset Offset in the packet to the L3 (IP or equiv.) header.
+ *
+ * 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.
+ * ip is the beginning of the ip(4 or 6) header.
+ * Calculated by adding the L3offset to the start of data.
+ * (Until we start using L3offset, the packet is
+ * supposed to start with the ip header).
+ */
+ struct mbuf *m = args->m;
+ struct ip *ip = mtod(m, struct ip *);
+
+ /*
+ * 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.
+ */
+ struct ip_fw_ugid fw_ugid_cache;
+ int ugid_lookup = 0;
+
+ /*
+ * divinput_flags If non-zero, set to the IP_FW_DIVERT_*_FLAG
+ * associated with a packet input on a divert socket. This
+ * will allow to distinguish traffic and its direction when
+ * it originates from a divert socket.
+ */
+ u_int divinput_flags = 0;
+
+ /*
+ * oif | args->oif If NULL, ipfw_chk has been called on the
+ * inbound path (ether_input, ip_input).
+ * If non-NULL, ipfw_chk has been called on the outbound path
+ * (ether_output, ip_output).
+ */
+ struct ifnet *oif = args->oif;
+
+ struct ip_fw *f = NULL; /* matching rule */
+ int retval = 0;
+
+ /*
+ * 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 == 0 means there is no Fragment Header.
+ * If offset != 0 for IPv6 always use correct mask to
+ * get the correct offset because we add IP6F_MORE_FRAG
+ * to be able to dectect the first fragment which would
+ * otherwise have offset = 0.
+ */
+ u_short offset = 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.
+ */
+ u_int8_t proto;
+ u_int16_t src_port = 0, dst_port = 0; /* NOTE: host format */
+ struct in_addr src_ip, dst_ip; /* NOTE: network format */
+ u_int16_t ip_len=0;
+ int pktlen;
+ u_int16_t etype = 0; /* Host order stored ether type */
+
+ /*
+ * dyn_dir = MATCH_UNKNOWN when rules unchecked,
+ * MATCH_NONE when checked and not matched (q = NULL),
+ * MATCH_FORWARD or MATCH_REVERSE otherwise (q != NULL)
+ */
+ int dyn_dir = MATCH_UNKNOWN;
+ ipfw_dyn_rule *q = NULL;
+ struct ip_fw_chain *chain = &layer3_chain;
+ struct m_tag *mtag;
+
+ /*
+ * 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;
+ u_int16_t ext_hd = 0; /* bits vector for extension header filtering */
+ /* end of ipv6 variables */
+ int is_ipv4 = 0;
+
+ if (m->m_flags & M_SKIP_FIREWALL)
+ return (IP_FW_PASS); /* accept */
+
+ dst_ip.s_addr = 0; /* make sure it is initialized */
+ src_ip.s_addr = 0; /* make sure it is initialized */
+ pktlen = m->m_pkthdr.len;
+ args->f_id.fib = M_GETFIB(m); /* note mbuf not altered) */
+ proto = args->f_id.proto = 0; /* mark f_id invalid */
+ /* XXX 0 is a valid proto: IP/IPv6 Hop-by-Hop Option */
+
+/*
+ * 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) \
+do { \
+ int x = (_len) + sizeof(T); \
+ if ((m)->m_len < x) { \
+ goto pullup_failed; \
+ } \
+ p = (mtod(m, char *) + (_len)); \
+} while (0)
+
+ /*
+ * if we have an ether header,
+ */
+ if (args->eh)
+ etype = ntohs(args->eh->ether_type);
+
+ /* Identify IP packets and fill up variables. */
+ if (pktlen >= sizeof(struct ip6_hdr) &&
+ (args->eh == NULL || etype == ETHERTYPE_IPV6) && ip->ip_v == 6) {
+ struct ip6_hdr *ip6 = (struct ip6_hdr *)ip;
+ is_ipv6 = 1;
+ args->f_id.addr_type = 6;
+ hlen = sizeof(struct ip6_hdr);
+ proto = ip6->ip6_nxt;
+
+ /* Search extension headers to find upper layer protocols */
+ while (ulp == NULL) {
+ switch (proto) {
+ case IPPROTO_ICMPV6:
+ PULLUP_TO(hlen, ulp, struct icmp6_hdr);
+ args->f_id.flags = ICMP6(ulp)->icmp6_type;
+ break;
+
+ case IPPROTO_TCP:
+ PULLUP_TO(hlen, ulp, struct tcphdr);
+ dst_port = TCP(ulp)->th_dport;
+ src_port = TCP(ulp)->th_sport;
+ args->f_id.flags = TCP(ulp)->th_flags;
+ break;
+
+ case IPPROTO_SCTP:
+ PULLUP_TO(hlen, ulp, struct sctphdr);
+ src_port = SCTP(ulp)->src_port;
+ dst_port = SCTP(ulp)->dest_port;
+ break;
+
+ case IPPROTO_UDP:
+ 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:
+ printf("IPFW2: IPV6 - Unknown Routing "
+ "Header type(%d)\n",
+ ((struct ip6_rthdr *)ulp)->ip6r_type);
+ if (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;
+ /* Add IP6F_MORE_FRAG for offset of first
+ * fragment to be != 0. */
+ offset |= ((struct ip6_frag *)ulp)->ip6f_offlg &
+ IP6F_MORE_FRAG;
+ if (offset == 0) {
+ printf("IPFW2: IPV6 - Invalid Fragment "
+ "Header\n");
+ if (fw_deny_unknown_exthdrs)
+ return (IP_FW_DENY);
+ break;
+ }
+ args->f_id.frag_id6 =
+ 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_CARP:
+ PULLUP_TO(hlen, ulp, struct carp_header);
+ if (((struct carp_header *)ulp)->carp_version !=
+ CARP_VERSION)
+ return (IP_FW_DENY);
+ if (((struct carp_header *)ulp)->carp_type !=
+ CARP_ADVERTISEMENT)
+ 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:
+ printf("IPFW2: IPV6 - Unknown Extension "
+ "Header(%d), ext_hd=%x\n", proto, ext_hd);
+ if (fw_deny_unknown_exthdrs)
+ return (IP_FW_DENY);
+ PULLUP_TO(hlen, ulp, struct ip6_ext);
+ break;
+ } /*switch */
+ }
+ ip = mtod(m, struct ip *);
+ ip6 = (struct ip6_hdr *)ip;
+ args->f_id.src_ip6 = ip6->ip6_src;
+ args->f_id.dst_ip6 = ip6->ip6_dst;
+ args->f_id.src_ip = 0;
+ args->f_id.dst_ip = 0;
+ args->f_id.flow_id6 = ntohl(ip6->ip6_flow);
+ } else if (pktlen >= sizeof(struct ip) &&
+ (args->eh == NULL || etype == ETHERTYPE_IP) && ip->ip_v == 4) {
+ is_ipv4 = 1;
+ hlen = ip->ip_hl << 2;
+ args->f_id.addr_type = 4;
+
+ /*
+ * Collect parameters into local variables for faster matching.
+ */
+ proto = ip->ip_p;
+ src_ip = ip->ip_src;
+ dst_ip = ip->ip_dst;
+
+ if (1 || args->eh != NULL) { /* layer 2 packets are as on the wire */
+ offset = ntohs(ip->ip_off) & IP_OFFMASK;
+ ip_len = ntohs(ip->ip_len);
+ } else {
+ offset = ip->ip_off & IP_OFFMASK;
+ ip_len = ip->ip_len;
+ }
+ pktlen = ip_len < pktlen ? ip_len : pktlen;
+
+ 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;
+ args->f_id.flags = TCP(ulp)->th_flags;
+ break;
+
+ case IPPROTO_UDP:
+ 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;
+ }
+ }
+
+ ip = mtod(m, struct ip *);
+ args->f_id.src_ip = ntohl(src_ip.s_addr);
+ args->f_id.dst_ip = ntohl(dst_ip.s_addr);
+ }
+#undef PULLUP_TO
+ if (proto) { /* we may have port numbers, store them */
+ 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_RLOCK(chain);
+ mtag = m_tag_find(m, PACKET_TAG_DIVERT, NULL);
+ if (args->rule) {
+ /*
+ * Packet has already been tagged. Look for the next rule
+ * to restart processing.
+ *
+ * If fw_one_pass != 0 then just accept it.
+ * XXX should not happen here, but optimized out in
+ * the caller.
+ */
+ if (fw_one_pass) {
+ IPFW_RUNLOCK(chain);
+ return (IP_FW_PASS);
+ }
+
+ f = args->rule->next_rule;
+ if (f == NULL)
+ f = lookup_next_rule(args->rule, 0);
+ } else {
+ /*
+ * Find the starting rule. It can be either the first
+ * one, or the one after divert_rule if asked so.
+ */
+ int skipto = mtag ? divert_cookie(mtag) : 0;
+
+ f = chain->rules;
+ if (args->eh == NULL && skipto != 0) {
+ if (skipto >= IPFW_DEFAULT_RULE) {
+ IPFW_RUNLOCK(chain);
+ return (IP_FW_DENY); /* invalid */
+ }
+ while (f && f->rulenum <= skipto)
+ f = f->next;
+ if (f == NULL) { /* drop packet */
+ IPFW_RUNLOCK(chain);
+ return (IP_FW_DENY);
+ }
+ }
+ }
+ /* reset divert rule to avoid confusion later */
+ if (mtag) {
+ divinput_flags = divert_info(mtag) &
+ (IP_FW_DIVERT_OUTPUT_FLAG | IP_FW_DIVERT_LOOPBACK_FLAG);
+ m_tag_delete(m, mtag);
+ }
+
+ /*
+ * Now scan the rules, and parse microinstructions for each rule.
+ */
+ for (; f; f = f->next) {
+ ipfw_insn *cmd;
+ uint32_t tablearg = 0;
+ int l, cmdlen, skip_or; /* skip rest of OR block */
+
+again:
+ if (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 (is_ipv6) /* XXX to be fixed later */
+ break;
+ if (proto == IPPROTO_TCP ||
+ proto == IPPROTO_UDP)
+ match = check_uidgid(
+ (ipfw_insn_u32 *)cmd,
+ proto, oif,
+ dst_ip, dst_port,
+ src_ip, src_port, &fw_ugid_cache,
+ &ugid_lookup, args->inp);
+ break;
+
+ case O_RECV:
+ match = iface_match(m->m_pkthdr.rcvif,
+ (ipfw_insn_if *)cmd);
+ break;
+
+ case O_XMIT:
+ match = iface_match(oif, (ipfw_insn_if *)cmd);
+ break;
+
+ case O_VIA:
+ match = iface_match(oif ? oif :
+ m->m_pkthdr.rcvif, (ipfw_insn_if *)cmd);
+ break;
+
+ case O_MACADDR2:
+ if (args->eh != NULL) { /* have MAC header */
+ 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 *)args->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->eh != NULL) {
+ u_int16_t *p =
+ ((ipfw_insn_u16 *)cmd)->ports;
+ int i;
+
+ for (i = cmdlen - 1; !match && i>0;
+ i--, p += 2)
+ match = (etype >= p[0] &&
+ etype <= p[1]);
+ }
+ break;
+
+ case O_FRAG:
+ match = (offset != 0);
+ break;
+
+ case O_IN: /* "out" is "not in" */
+ match = (oif == NULL);
+ break;
+
+ case O_LAYER2:
+ match = (args->eh != NULL);
+ break;
+
+ case O_DIVERTED:
+ match = (cmd->arg1 & 1 && divinput_flags &
+ IP_FW_DIVERT_LOOPBACK_FLAG) ||
+ (cmd->arg1 & 2 && divinput_flags &
+ IP_FW_DIVERT_OUTPUT_FLAG);
+ 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_SRC_LOOKUP:
+ case O_IP_DST_LOOKUP:
+ if (is_ipv4) {
+ uint32_t a =
+ (cmd->opcode == O_IP_DST_LOOKUP) ?
+ dst_ip.s_addr : src_ip.s_addr;
+ uint32_t v = 0;
+
+ match = lookup_table(chain, cmd->arg1, a,
+ &v);
+ if (!match)
+ break;
+ if (cmdlen == F_INSN_SIZE(ipfw_insn_u32))
+ match =
+ ((ipfw_insn_u32 *)cmd)->d[0] == v;
+ else
+ 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) {
+ struct ifnet *tif;
+
+ INADDR_TO_IFP(src_ip, tif);
+ match = (tif != NULL);
+ }
+ 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) {
+ struct ifnet *tif;
+
+ INADDR_TO_IFP(dst_ip, tif);
+ match = (tif != NULL);
+ }
+ 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_TCP)
+ && 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 &&
+ cmd->arg1 == ip->ip_v);
+ break;
+
+ case O_IPID:
+ case O_IPLEN:
+ case O_IPTTL:
+ if (is_ipv4) { /* only for IP packets */
+ uint16_t x;
+ uint16_t *p;
+ int i;
+
+ if (cmd->opcode == O_IPLEN)
+ x = ip_len;
+ 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_TCPDATALEN:
+ if (proto == IPPROTO_TCP && offset == 0) {
+ struct tcphdr *tcp;
+ uint16_t x;
+ uint16_t *p;
+ int i;
+
+ tcp = TCP(ulp);
+ x = ip_len -
+ ((ip->ip_hl + 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:
+ match = (proto == IPPROTO_TCP && offset == 0 &&
+ 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_TCPWIN:
+ match = (proto == IPPROTO_TCP && offset == 0 &&
+ cmd->arg1 == TCP(ulp)->th_win);
+ 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;
+ ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
+
+ match = 1;
+ at = pf_find_mtag(m);
+ if (at != NULL && at->qid != 0)
+ break;
+ at = pf_get_mtag(m);
+ if (at == NULL) {
+ /*
+ * Let the packet fall back to the
+ * default ALTQ.
+ */
+ break;
+ }
+ at->qid = altq->qid;
+ if (is_ipv4)
+ at->af = AF_INET;
+ else
+ at->af = AF_LINK;
+ at->hdr = ip;
+ break;
+ }
+
+ case O_LOG:
+ if (fw_verbose)
+ ipfw_log(f, hlen, args, m,
+ oif, offset, tablearg, ip);
+ match = 1;
+ break;
+
+ case O_PROB:
+ match = (random()<((ipfw_insn_u32 *)cmd)->d[0]);
+ break;
+
+#if 0
+ case O_VERREVPATH:
+ /* Outgoing packets automatically pass/match */
+ match = ((oif != NULL) ||
+ (m->m_pkthdr.rcvif == NULL) ||
+ (
+#ifdef INET6
+ is_ipv6 ?
+ verify_path6(&(args->f_id.src_ip6),
+ m->m_pkthdr.rcvif) :
+#endif
+ verify_path(src_ip, m->m_pkthdr.rcvif,
+ 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) :
+#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),
+ m->m_pkthdr.rcvif) :
+#endif
+ verify_path(src_ip,
+ m->m_pkthdr.rcvif,
+ args->f_id.fib);
+ else
+ match = 1;
+ break;
+#endif
+
+ case O_IPSEC:
+#ifdef IPSEC
+ match = (m_tag_find(m,
+ PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL);
+#endif
+ /* 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_IP6_SRC_ME:
+ match= is_ipv6 && search_ip6_addr_net(&args->f_id.src_ip6);
+ break;
+
+ case O_IP6_DST_ME:
+ match= is_ipv6 && search_ip6_addr_net(&args->f_id.dst_ip6);
+ 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;
+
+#if 0
+ case O_TAG: {
+ uint32_t tag = (cmd->arg1 == IP_FW_TABLEARG) ?
+ tablearg : cmd->arg1;
+
+ /* 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);
+ } else if (mtag == NULL) {
+ if ((mtag = m_tag_alloc(MTAG_IPFW,
+ tag, 0, M_NOWAIT)) != NULL)
+ m_tag_prepend(m, mtag);
+ }
+ match = (cmd->len & F_NOT) ? 0: 1;
+ break;
+ }
+
+ case O_FIB: /* try match the specified fib */
+ if (args->f_id.fib == cmd->arg1)
+ match = 1;
+ break;
+
+ case O_TAGGED: {
+ uint32_t tag = (cmd->arg1 == IP_FW_TABLEARG) ?
+ tablearg : cmd->arg1;
+
+ 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;
+ }
+#endif
+
+ /*
+ * 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 do a 'goto done').
+ *
+ * Exceptions:
+ * O_COUNT and O_SKIPTO actions:
+ * instead of terminating, we jump to the next rule
+ * ('goto next_rule', equivalent to a 'break 2'),
+ * or to the SKIPTO target ('goto again' after
+ * having set f, cmd and l), 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.
+ * 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
+ * ('goto done' after setting retval);
+ *
+ * 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
+ * ('goto check_body') if an entry is found, or
+ * (CHECK_STATE only) a jump to the next rule if
+ * the entry is not found ('goto next_rule').
+ * The result of the lookup is cached to make
+ * further instances of these opcodes are
+ * effectively NOPs.
+ */
+ case O_LIMIT:
+ case O_KEEP_STATE:
+ if (install_state(f,
+ (ipfw_insn_limit *)cmd, args, tablearg)) {
+ retval = IP_FW_DENY;
+ goto done; /* error/limit violation */
+ }
+ 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_dir.
+ * 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_dir == MATCH_UNKNOWN &&
+ (q = lookup_dyn_rule(&args->f_id,
+ &dyn_dir, proto == IPPROTO_TCP ?
+ TCP(ulp) : NULL))
+ != NULL) {
+ /*
+ * Found dynamic entry, update stats
+ * and jump to the 'action' part of
+ * the parent rule.
+ */
+ q->pcnt++;
+ q->bcnt += pktlen;
+ f = q->rule;
+ cmd = ACTION_PTR(f);
+ l = f->cmd_len - f->act_ofs;
+ IPFW_DYN_UNLOCK();
+ goto check_body;
+ }
+ /*
+ * 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)
+ goto next_rule;
+ match = 1;
+ break;
+
+ case O_ACCEPT:
+ retval = 0; /* accept */
+ goto done;
+
+ case O_PIPE:
+ case O_QUEUE:
+ args->rule = f; /* report matching rule */
+ if (cmd->arg1 == IP_FW_TABLEARG)
+ args->cookie = tablearg;
+ else
+ args->cookie = cmd->arg1;
+ retval = IP_FW_DUMMYNET;
+ goto done;
+
+#if 0
+ case O_DIVERT:
+ case O_TEE: {
+ struct divert_tag *dt;
+
+ if (args->eh) /* not on layer 2 */
+ break;
+ mtag = m_tag_get(PACKET_TAG_DIVERT,
+ sizeof(struct divert_tag),
+ M_NOWAIT);
+ if (mtag == NULL) {
+ /* XXX statistic */
+ /* drop packet */
+ IPFW_RUNLOCK(chain);
+ return (IP_FW_DENY);
+ }
+ dt = (struct divert_tag *)(mtag+1);
+ dt->cookie = f->rulenum;
+ if (cmd->arg1 == IP_FW_TABLEARG)
+ dt->info = tablearg;
+ else
+ dt->info = cmd->arg1;
+ m_tag_prepend(m, mtag);
+ retval = (cmd->opcode == O_DIVERT) ?
+ IP_FW_DIVERT : IP_FW_TEE;
+ goto done;
+ }
+#endif
+
+ case O_COUNT:
+ case O_SKIPTO:
+ f->pcnt++; /* update stats */
+ f->bcnt += pktlen;
+ f->timestamp = time_uptime;
+ if (cmd->opcode == O_COUNT)
+ goto next_rule;
+ /* handle skipto */
+ if (cmd->arg1 == IP_FW_TABLEARG) {
+ f = lookup_next_rule(f, tablearg);
+ } else {
+ if (f->next_rule == NULL)
+ lookup_next_rule(f, 0);
+ f = f->next_rule;
+ }
+ goto again;
+
+ 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->arg1, ip_len, 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(args->f_id.flags) == 1)) &&
+ !(m->m_flags & (M_BCAST|M_MCAST)) &&
+ !IN6_IS_ADDR_MULTICAST(&args->f_id.dst_ip6)) {
+ send_reject6(
+ args, cmd->arg1, hlen,
+ (struct ip6_hdr *)ip);
+ m = args->m;
+ }
+ /* FALLTHROUGH */
+#endif
+ case O_DENY:
+ retval = IP_FW_DENY;
+ goto done;
+
+ case O_FORWARD_IP: {
+ struct sockaddr_in *sa;
+ sa = &(((ipfw_insn_sa *)cmd)->sa);
+ if (args->eh) /* not valid on layer2 pkts */
+ break;
+ if (!q || dyn_dir == MATCH_FORWARD) {
+ if (sa->sin_addr.s_addr == INADDR_ANY) {
+ bcopy(sa, &args->hopstore,
+ sizeof(*sa));
+ args->hopstore.sin_addr.s_addr =
+ htonl(tablearg);
+ args->next_hop =
+ &args->hopstore;
+ } else {
+ args->next_hop = sa;
+ }
+ }
+ retval = IP_FW_PASS;
+ }
+ goto done;
+
+ case O_NETGRAPH:
+ case O_NGTEE:
+ args->rule = f; /* report matching rule */
+ if (cmd->arg1 == IP_FW_TABLEARG)
+ args->cookie = tablearg;
+ else
+ args->cookie = cmd->arg1;
+ retval = (cmd->opcode == O_NETGRAPH) ?
+ IP_FW_NETGRAPH : IP_FW_NGTEE;
+ goto done;
+
+#if 0
+ case O_SETFIB:
+ f->pcnt++; /* update stats */
+ f->bcnt += pktlen;
+ f->timestamp = time_uptime;
+ M_SETFIB(m, cmd->arg1);
+ args->f_id.fib = cmd->arg1;
+ goto next_rule;
+
+ case O_NAT: {
+ struct cfg_nat *t;
+ int nat_id;
+
+ if (IPFW_NAT_LOADED) {
+ args->rule = f; /* Report matching rule. */
+ t = ((ipfw_insn_nat *)cmd)->nat;
+ if (t == NULL) {
+ nat_id = (cmd->arg1 == IP_FW_TABLEARG) ?
+ tablearg : cmd->arg1;
+ LOOKUP_NAT(layer3_chain, nat_id, t);
+ if (t == NULL) {
+ retval = IP_FW_DENY;
+ goto done;
+ }
+ if (cmd->arg1 != IP_FW_TABLEARG)
+ ((ipfw_insn_nat *)cmd)->nat = t;
+ }
+ retval = ipfw_nat_ptr(args, t, m);
+ } else
+ retval = IP_FW_DENY;
+ goto done;
+ }
+#endif
+
+ default:
+ break; // XXX we disabled some
+ panic("-- unknown opcode %d\n", cmd->opcode);
+ } /* end of switch() on opcodes */
+
+ 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 for, scan opcodes */
+
+next_rule:; /* try next rule */
+
+ } /* end of outer for, scan rules */
+ printf("ipfw: ouch!, skip past end of rules, denying packet\n");
+ IPFW_RUNLOCK(chain);
+ return (IP_FW_DENY);
+
+done:
+ /* Update statistics */
+ f->pcnt++;
+ f->bcnt += pktlen;
+ f->timestamp = time_uptime;
+ IPFW_RUNLOCK(chain);
+ return (retval);
+
+pullup_failed:
+ if (fw_verbose)
+ printf("ipfw: pullup failed\n");
+ return (IP_FW_DENY);
+}
+
+/*
+ * When a rule is added/deleted, clear the next_rule pointers in all rules.
+ * These will be reconstructed on the fly as packets are matched.
+ */
+static void
+flush_rule_ptrs(struct ip_fw_chain *chain)
+{
+ struct ip_fw *rule;
+
+ IPFW_WLOCK_ASSERT(chain);
+
+ for (rule = chain->rules; rule; rule = rule->next)
+ rule->next_rule = NULL;
+}
+
+/*
+ * Add a new rule to the list. Copy the rule into a malloc'ed area, then
+ * possibly create a rule number and add the rule to the list.
+ * Update the rule_number in the input struct so the caller knows it as well.
+ */
+static int
+add_rule(struct ip_fw_chain *chain, struct ip_fw *input_rule)
+{
+ struct ip_fw *rule, *f, *prev;
+ int l = RULESIZE(input_rule);
+
+ if (chain->rules == NULL && input_rule->rulenum != IPFW_DEFAULT_RULE)
+ return (EINVAL);
+
+ rule = malloc(l, M_IPFW, M_NOWAIT | M_ZERO);
+ if (rule == NULL)
+ return (ENOSPC);
+
+ bcopy(input_rule, rule, l);
+
+ rule->next = NULL;
+ rule->next_rule = NULL;
+
+ rule->pcnt = 0;
+ rule->bcnt = 0;
+ rule->timestamp = 0;
+
+ IPFW_WLOCK(chain);
+
+ if (chain->rules == NULL) { /* default rule */
+ chain->rules = rule;
+ goto done;
+ }
+
+ /*
+ * If rulenum is 0, find highest numbered rule before the
+ * default rule, and add autoinc_step
+ */
+ if (autoinc_step < 1)
+ autoinc_step = 1;
+ else if (autoinc_step > 1000)
+ autoinc_step = 1000;
+ if (rule->rulenum == 0) {
+ /*
+ * locate the highest numbered rule before default
+ */
+ for (f = chain->rules; f; f = f->next) {
+ if (f->rulenum == IPFW_DEFAULT_RULE)
+ break;
+ rule->rulenum = f->rulenum;
+ }
+ if (rule->rulenum < IPFW_DEFAULT_RULE - autoinc_step)
+ rule->rulenum += autoinc_step;
+ input_rule->rulenum = rule->rulenum;
+ }
+
+ /*
+ * Now insert the new rule in the right place in the sorted list.
+ */
+ for (prev = NULL, f = chain->rules; f; prev = f, f = f->next) {
+ if (f->rulenum > rule->rulenum) { /* found the location */
+ if (prev) {
+ rule->next = f;
+ prev->next = rule;
+ } else { /* head insert */
+ rule->next = chain->rules;
+ chain->rules = rule;
+ }
+ break;
+ }
+ }
+ flush_rule_ptrs(chain);
+done:
+ static_count++;
+ static_len += l;
+ IPFW_WUNLOCK(chain);
+ DEB(printf("ipfw: installed rule %d, static count now %d\n",
+ rule->rulenum, static_count);)
+ return (0);
+}
+
+/**
+ * Remove a static rule (including derived * dynamic rules)
+ * and place it on the ``reap list'' for later reclamation.
+ * The caller is in charge of clearing rule pointers to avoid
+ * dangling pointers.
+ * @return a pointer to the next entry.
+ * Arguments are not checked, so they better be correct.
+ */
+static struct ip_fw *
+remove_rule(struct ip_fw_chain *chain, struct ip_fw *rule,
+ struct ip_fw *prev)
+{
+ struct ip_fw *n;
+ int l = RULESIZE(rule);
+
+ IPFW_WLOCK_ASSERT(chain);
+
+ n = rule->next;
+ IPFW_DYN_LOCK();
+ remove_dyn_rule(rule, NULL /* force removal */);
+ IPFW_DYN_UNLOCK();
+ if (prev == NULL)
+ chain->rules = n;
+ else
+ prev->next = n;
+ static_count--;
+ static_len -= l;
+
+ rule->next = chain->reap;
+ chain->reap = rule;
+
+ return n;
+}
+
+/*
+ * Hook for cleaning up dummynet when an ipfw rule is deleted.
+ * Set/cleared when dummynet module is loaded/unloaded.
+ */
+void (*ip_dn_ruledel_ptr)(void *) = NULL;
+
+/**
+ * Reclaim storage associated with a list of rules. This is
+ * typically the list created using remove_rule.
+ * A NULL pointer on input is handled correctly.
+ */
+static void
+reap_rules(struct ip_fw *head)
+{
+ struct ip_fw *rule;
+
+ while ((rule = head) != NULL) {
+ head = head->next;
+ if (ip_dn_ruledel_ptr)
+ ip_dn_ruledel_ptr(rule);
+ free(rule, M_IPFW);
+ }
+}
+
+/*
+ * Remove all rules from a chain (except rules in set RESVD_SET
+ * unless kill_default = 1). The caller is responsible for
+ * reclaiming storage for the rules left in chain->reap.
+ */
+static void
+free_chain(struct ip_fw_chain *chain, int kill_default)
+{
+ struct ip_fw *prev, *rule;
+
+ IPFW_WLOCK_ASSERT(chain);
+
+ flush_rule_ptrs(chain); /* more efficient to do outside the loop */
+ for (prev = NULL, rule = chain->rules; rule ; )
+ if (kill_default || rule->set != RESVD_SET)
+ rule = remove_rule(chain, rule, prev);
+ else {
+ prev = rule;
+ rule = rule->next;
+ }
+}
+
+/**
+ * Remove all rules with given number, and also do set manipulation.
+ * Assumes chain != NULL && *chain != NULL.
+ *
+ * The argument is an u_int32_t. The low 16 bit are the rule or set number,
+ * the next 8 bits are the new set, the top 8 bits are the command:
+ *
+ * 0 delete rules with given number
+ * 1 delete rules with given set number
+ * 2 move rules with given number to new set
+ * 3 move rules with given set number to new set
+ * 4 swap sets with given numbers
+ * 5 delete rules with given number and with given set number
+ */
+static int
+del_entry(struct ip_fw_chain *chain, u_int32_t arg)
+{
+ struct ip_fw *prev = NULL, *rule;
+ u_int16_t rulenum; /* rule or old_set */
+ u_int8_t cmd, new_set;
+
+ rulenum = arg & 0xffff;
+ cmd = (arg >> 24) & 0xff;
+ new_set = (arg >> 16) & 0xff;
+
+ if (cmd > 5 || new_set > RESVD_SET)
+ return EINVAL;
+ if (cmd == 0 || cmd == 2 || cmd == 5) {
+ if (rulenum >= IPFW_DEFAULT_RULE)
+ return EINVAL;
+ } else {
+ if (rulenum > RESVD_SET) /* old_set */
+ return EINVAL;
+ }
+
+ IPFW_WLOCK(chain);
+ rule = chain->rules;
+ chain->reap = NULL;
+ switch (cmd) {
+ case 0: /* delete rules with given number */
+ /*
+ * locate first rule to delete
+ */
+ for (; rule->rulenum < rulenum; prev = rule, rule = rule->next)
+ ;
+ if (rule->rulenum != rulenum) {
+ IPFW_WUNLOCK(chain);
+ return EINVAL;
+ }
+
+ /*
+ * flush pointers outside the loop, then delete all matching
+ * rules. prev remains the same throughout the cycle.
+ */
+ flush_rule_ptrs(chain);
+ while (rule->rulenum == rulenum)
+ rule = remove_rule(chain, rule, prev);
+ break;
+
+ case 1: /* delete all rules with given set number */
+ flush_rule_ptrs(chain);
+ rule = chain->rules;
+ while (rule->rulenum < IPFW_DEFAULT_RULE)
+ if (rule->set == rulenum)
+ rule = remove_rule(chain, rule, prev);
+ else {
+ prev = rule;
+ rule = rule->next;
+ }
+ break;
+
+ case 2: /* move rules with given number to new set */
+ rule = chain->rules;
+ for (; rule->rulenum < IPFW_DEFAULT_RULE; rule = rule->next)
+ if (rule->rulenum == rulenum)
+ rule->set = new_set;
+ break;
+
+ case 3: /* move rules with given set number to new set */
+ for (; rule->rulenum < IPFW_DEFAULT_RULE; rule = rule->next)
+ if (rule->set == rulenum)
+ rule->set = new_set;
+ break;
+
+ case 4: /* swap two sets */
+ for (; rule->rulenum < IPFW_DEFAULT_RULE; rule = rule->next)
+ if (rule->set == rulenum)
+ rule->set = new_set;
+ else if (rule->set == new_set)
+ rule->set = rulenum;
+ break;
+ case 5: /* delete rules with given number and with given set number.
+ * rulenum - given rule number;
+ * new_set - given set number.
+ */
+ for (; rule->rulenum < rulenum; prev = rule, rule = rule->next)
+ ;
+ if (rule->rulenum != rulenum) {
+ IPFW_WUNLOCK(chain);
+ return (EINVAL);
+ }
+ flush_rule_ptrs(chain);
+ while (rule->rulenum == rulenum) {
+ if (rule->set == new_set)
+ rule = remove_rule(chain, rule, prev);
+ else {
+ prev = rule;
+ rule = rule->next;
+ }
+ }
+ }
+ /*
+ * Look for rules to reclaim. We grab the list before
+ * releasing the lock then reclaim them w/o the lock to
+ * avoid a LOR with dummynet.
+ */
+ rule = chain->reap;
+ chain->reap = NULL;
+ IPFW_WUNLOCK(chain);
+ if (rule)
+ reap_rules(rule);
+ return 0;
+}
+
+/*
+ * Clear counters for a specific rule.
+ * The enclosing "table" is assumed locked.
+ */
+static void
+clear_counters(struct ip_fw *rule, int log_only)
+{
+ ipfw_insn_log *l = (ipfw_insn_log *)ACTION_PTR(rule);
+
+ if (log_only == 0) {
+ rule->bcnt = rule->pcnt = 0;
+ rule->timestamp = 0;
+ }
+ if (l->o.opcode == O_LOG)
+ l->log_left = l->max_log;
+}
+
+/**
+ * Reset some or all counters on firewall rules.
+ * The argument `arg' is an u_int32_t. The low 16 bit are the rule number,
+ * the next 8 bits are the set number, the top 8 bits are the command:
+ * 0 work with rules from all set's;
+ * 1 work with rules only from specified set.
+ * Specified rule number is zero if we want to clear all entries.
+ * log_only is 1 if we only want to reset logs, zero otherwise.
+ */
+static int
+zero_entry(struct ip_fw_chain *chain, u_int32_t arg, int log_only)
+{
+ struct ip_fw *rule;
+ char *msg;
+
+ uint16_t rulenum = arg & 0xffff;
+ uint8_t set = (arg >> 16) & 0xff;
+ uint8_t cmd = (arg >> 24) & 0xff;
+
+ if (cmd > 1)
+ return (EINVAL);
+ if (cmd == 1 && set > RESVD_SET)
+ return (EINVAL);
+
+ IPFW_WLOCK(chain);
+ if (rulenum == 0) {
+ norule_counter = 0;
+ for (rule = chain->rules; rule; rule = rule->next) {
+ /* Skip rules from another set. */
+ if (cmd == 1 && rule->set != set)
+ continue;
+ clear_counters(rule, log_only);
+ }
+ msg = log_only ? "All logging counts reset" :
+ "Accounting cleared";
+ } else {
+ int cleared = 0;
+ /*
+ * We can have multiple rules with the same number, so we
+ * need to clear them all.
+ */
+ for (rule = chain->rules; rule; rule = rule->next)
+ if (rule->rulenum == rulenum) {
+ while (rule && rule->rulenum == rulenum) {
+ if (cmd == 0 || rule->set == set)
+ clear_counters(rule, log_only);
+ rule = rule->next;
+ }
+ cleared = 1;
+ break;
+ }
+ if (!cleared) { /* we did not find any matching rules */
+ IPFW_WUNLOCK(chain);
+ return (EINVAL);
+ }
+ msg = log_only ? "logging count reset" : "cleared";
+ }
+ IPFW_WUNLOCK(chain);
+
+ if (fw_verbose) {
+#define lev LOG_SECURITY | LOG_NOTICE
+
+ if (rulenum)
+ log(lev, "ipfw: Entry %d %s.\n", rulenum, msg);
+ else
+ log(lev, "ipfw: %s.\n", msg);
+ }
+ return (0);
+}
+
+/*
+ * Check validity of the structure before insert.
+ * Fortunately rules are simple, so this mostly need to check rule sizes.
+ */
+static int
+check_ipfw_struct(struct ip_fw *rule, int size)
+{
+ int l, cmdlen = 0;
+ int have_action=0;
+ ipfw_insn *cmd;
+
+ if (size < sizeof(*rule)) {
+ printf("ipfw: rule too short\n");
+ return (EINVAL);
+ }
+ /* first, check for valid size */
+ l = RULESIZE(rule);
+ if (l != size) {
+ printf("ipfw: size mismatch (have %d want %d)\n", size, l);
+ return (EINVAL);
+ }
+ if (rule->act_ofs >= rule->cmd_len) {
+ printf("ipfw: bogus action offset (%u > %u)\n",
+ rule->act_ofs, rule->cmd_len - 1);
+ return (EINVAL);
+ }
+ /*
+ * Now go for the individual checks. Very simple ones, basically only
+ * instruction sizes.
+ */
+ for (l = rule->cmd_len, cmd = rule->cmd ;
+ l > 0 ; l -= cmdlen, cmd += cmdlen) {
+ cmdlen = F_LEN(cmd);
+ if (cmdlen > l) {
+ printf("ipfw: opcode %d size truncated\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ DEB(printf("ipfw: opcode %d\n", cmd->opcode);)
+ switch (cmd->opcode) {
+ case O_PROBE_STATE:
+ case O_KEEP_STATE:
+ case O_PROTO:
+ case O_IP_SRC_ME:
+ case O_IP_DST_ME:
+ case O_LAYER2:
+ case O_IN:
+ case O_FRAG:
+ case O_DIVERTED:
+ case O_IPOPT:
+ case O_IPTOS:
+ case O_IPPRECEDENCE:
+ case O_IPVER:
+ case O_TCPWIN:
+ case O_TCPFLAGS:
+ case O_TCPOPTS:
+ case O_ESTAB:
+ case O_VERREVPATH:
+ case O_VERSRCREACH:
+ case O_ANTISPOOF:
+ case O_IPSEC:
+#ifdef INET6
+ case O_IP6_SRC_ME:
+ case O_IP6_DST_ME:
+ case O_EXT_HDR:
+ case O_IP6:
+#endif
+ case O_IP4:
+ case O_TAG:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn))
+ goto bad_size;
+ break;
+
+ case O_FIB:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn))
+ goto bad_size;
+ if (cmd->arg1 >= rt_numfibs) {
+ printf("ipfw: invalid fib number %d\n",
+ cmd->arg1);
+ return EINVAL;
+ }
+ break;
+
+ case O_SETFIB:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn))
+ goto bad_size;
+ if (cmd->arg1 >= rt_numfibs) {
+ printf("ipfw: invalid fib number %d\n",
+ cmd->arg1);
+ return EINVAL;
+ }
+ goto check_action;
+
+ case O_UID:
+ case O_GID:
+ case O_JAIL:
+ case O_IP_SRC:
+ case O_IP_DST:
+ case O_TCPSEQ:
+ case O_TCPACK:
+ case O_PROB:
+ case O_ICMPTYPE:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_u32))
+ goto bad_size;
+ break;
+
+ case O_LIMIT:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_limit))
+ goto bad_size;
+ break;
+
+ case O_LOG:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_log))
+ goto bad_size;
+
+ ((ipfw_insn_log *)cmd)->log_left =
+ ((ipfw_insn_log *)cmd)->max_log;
+
+ break;
+
+ case O_IP_SRC_MASK:
+ case O_IP_DST_MASK:
+ /* only odd command lengths */
+ if ( !(cmdlen & 1) || cmdlen > 31)
+ goto bad_size;
+ break;
+
+ case O_IP_SRC_SET:
+ case O_IP_DST_SET:
+ if (cmd->arg1 == 0 || cmd->arg1 > 256) {
+ printf("ipfw: invalid set size %d\n",
+ cmd->arg1);
+ return EINVAL;
+ }
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_u32) +
+ (cmd->arg1+31)/32 )
+ goto bad_size;
+ break;
+
+ case O_IP_SRC_LOOKUP:
+ case O_IP_DST_LOOKUP:
+ if (cmd->arg1 >= IPFW_TABLES_MAX) {
+ printf("ipfw: invalid table number %d\n",
+ cmd->arg1);
+ return (EINVAL);
+ }
+ if (cmdlen != F_INSN_SIZE(ipfw_insn) &&
+ cmdlen != F_INSN_SIZE(ipfw_insn_u32))
+ goto bad_size;
+ break;
+
+ case O_MACADDR2:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_mac))
+ goto bad_size;
+ break;
+
+ case O_NOP:
+ case O_IPID:
+ case O_IPTTL:
+ case O_IPLEN:
+ case O_TCPDATALEN:
+ case O_TAGGED:
+ if (cmdlen < 1 || cmdlen > 31)
+ goto bad_size;
+ break;
+
+ case O_MAC_TYPE:
+ case O_IP_SRCPORT:
+ case O_IP_DSTPORT: /* XXX artificial limit, 30 port pairs */
+ if (cmdlen < 2 || cmdlen > 31)
+ goto bad_size;
+ break;
+
+ case O_RECV:
+ case O_XMIT:
+ case O_VIA:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_if))
+ goto bad_size;
+ break;
+
+ case O_ALTQ:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_altq))
+ goto bad_size;
+ break;
+
+ case O_PIPE:
+ case O_QUEUE:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn))
+ goto bad_size;
+ goto check_action;
+
+ case O_FORWARD_IP:
+#ifdef IPFIREWALL_FORWARD
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_sa))
+ goto bad_size;
+ goto check_action;
+#else
+ return EINVAL;
+#endif
+
+ case O_DIVERT:
+ case O_TEE:
+ if (ip_divert_ptr == NULL)
+ return EINVAL;
+ else
+ goto check_size;
+ case O_NETGRAPH:
+ case O_NGTEE:
+ if (!NG_IPFW_LOADED)
+ return EINVAL;
+ else
+ goto check_size;
+ case O_NAT:
+ if (!IPFW_NAT_LOADED)
+ return EINVAL;
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_nat))
+ goto bad_size;
+ goto check_action;
+ case O_FORWARD_MAC: /* XXX not implemented yet */
+ case O_CHECK_STATE:
+ case O_COUNT:
+ case O_ACCEPT:
+ case O_DENY:
+ case O_REJECT:
+#ifdef INET6
+ case O_UNREACH6:
+#endif
+ case O_SKIPTO:
+check_size:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn))
+ goto bad_size;
+check_action:
+ if (have_action) {
+ printf("ipfw: opcode %d, multiple actions"
+ " not allowed\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ have_action = 1;
+ if (l != cmdlen) {
+ printf("ipfw: opcode %d, action must be"
+ " last opcode\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ break;
+#ifdef INET6
+ case O_IP6_SRC:
+ case O_IP6_DST:
+ if (cmdlen != F_INSN_SIZE(struct in6_addr) +
+ F_INSN_SIZE(ipfw_insn))
+ goto bad_size;
+ break;
+
+ case O_FLOW6ID:
+ if (cmdlen != F_INSN_SIZE(ipfw_insn_u32) +
+ ((ipfw_insn_u32 *)cmd)->o.arg1)
+ goto bad_size;
+ break;
+
+ case O_IP6_SRC_MASK:
+ case O_IP6_DST_MASK:
+ if ( !(cmdlen & 1) || cmdlen > 127)
+ goto bad_size;
+ break;
+ case O_ICMP6TYPE:
+ if( cmdlen != F_INSN_SIZE( ipfw_insn_icmp6 ) )
+ goto bad_size;
+ break;
+#endif
+
+ default:
+ switch (cmd->opcode) {
+#ifndef INET6
+ case O_IP6_SRC_ME:
+ case O_IP6_DST_ME:
+ case O_EXT_HDR:
+ case O_IP6:
+ case O_UNREACH6:
+ case O_IP6_SRC:
+ case O_IP6_DST:
+ case O_FLOW6ID:
+ case O_IP6_SRC_MASK:
+ case O_IP6_DST_MASK:
+ case O_ICMP6TYPE:
+ printf("ipfw: no IPv6 support in kernel\n");
+ return EPROTONOSUPPORT;
+#endif
+ default:
+ printf("ipfw: opcode %d, unknown opcode\n",
+ cmd->opcode);
+ return EINVAL;
+ }
+ }
+ }
+ if (have_action == 0) {
+ printf("ipfw: missing action\n");
+ return EINVAL;
+ }
+ return 0;
+
+bad_size:
+ printf("ipfw: opcode %d size %d wrong\n",
+ cmd->opcode, cmdlen);
+ return EINVAL;
+}
+
+/*
+ * Copy the static and dynamic rules to the supplied buffer
+ * and return the amount of space actually used.
+ */
+static size_t
+ipfw_getrules(struct ip_fw_chain *chain, void *buf, size_t space)
+{
+ char *bp = buf;
+ char *ep = bp + space;
+ struct ip_fw *rule;
+ int i;
+ time_t boot_seconds;
+
+ boot_seconds = boottime.tv_sec;
+ /* XXX this can take a long time and locking will block packet flow */
+ IPFW_RLOCK(chain);
+ for (rule = chain->rules; rule ; rule = rule->next) {
+ /*
+ * Verify the entry fits in the buffer in case the
+ * rules changed between calculating buffer space and
+ * now. This would be better done using a generation
+ * number but should suffice for now.
+ */
+ i = RULESIZE(rule);
+ if (bp + i <= ep) {
+ bcopy(rule, bp, i);
+ /*
+ * XXX HACK. Store the disable mask in the "next" pointer
+ * in a wild attempt to keep the ABI the same.
+ * Why do we do this on EVERY rule?
+ */
+ bcopy(&set_disable, &(((struct ip_fw *)bp)->next_rule),
+ sizeof(set_disable));
+ if (((struct ip_fw *)bp)->timestamp)
+ ((struct ip_fw *)bp)->timestamp += boot_seconds;
+ bp += i;
+ }
+ }
+ IPFW_RUNLOCK(chain);
+ if (ipfw_dyn_v) {
+ ipfw_dyn_rule *p, *last = NULL;
+
+ IPFW_DYN_LOCK();
+ for (i = 0 ; i < curr_dyn_buckets; i++)
+ for (p = ipfw_dyn_v[i] ; p != NULL; p = p->next) {
+ if (bp + sizeof *p <= ep) {
+ ipfw_dyn_rule *dst =
+ (ipfw_dyn_rule *)bp;
+ bcopy(p, dst, sizeof *p);
+ bcopy(&(p->rule->rulenum), &(dst->rule),
+ sizeof(p->rule->rulenum));
+ /*
+ * store set number into high word of
+ * dst->rule pointer.
+ */
+ bcopy(&(p->rule->set),
+ (char *)&dst->rule +
+ sizeof(p->rule->rulenum),
+ sizeof(p->rule->set));
+ /*
+ * store a non-null value in "next".
+ * The userland code will interpret a
+ * NULL here as a marker
+ * for the last dynamic rule.
+ */
+ bcopy(&dst, &dst->next, sizeof(dst));
+ last = dst;
+ dst->expire =
+ TIME_LEQ(dst->expire, time_uptime) ?
+ 0 : dst->expire - time_uptime ;
+ bp += sizeof(ipfw_dyn_rule);
+ }
+ }
+ IPFW_DYN_UNLOCK();
+ if (last != NULL) /* mark last dynamic rule */
+ bzero(&last->next, sizeof(last));
+ }
+ return (bp - (char *)buf);
+}
+
+
+/**
+ * {set|get}sockopt parser.
+ */
+static int
+ipfw_ctl(struct sockopt *sopt)
+{
+#define RULE_MAXSIZE (256*sizeof(u_int32_t))
+ int error;
+ size_t size;
+ struct ip_fw *buf, *rule;
+ u_int32_t rulenum[2];
+
+ error = priv_check(sopt->sopt_td, PRIV_NETINET_IPFW);
+ if (error)
+ return (error);
+
+ /*
+ * Disallow modifications in really-really secure mode, but still allow
+ * the logging counters to be reset.
+ */
+ if (sopt->sopt_name == IP_FW_ADD ||
+ (sopt->sopt_dir == SOPT_SET && sopt->sopt_name != IP_FW_RESETLOG)) {
+ error = securelevel_ge(sopt->sopt_td->td_ucred, 3);
+ if (error)
+ return (error);
+ }
+
+ error = 0;
+
+ switch (sopt->sopt_name) {
+ case IP_FW_GET:
+ /*
+ * pass up a copy of the current rules. Static rules
+ * come first (the last of which has number IPFW_DEFAULT_RULE),
+ * followed by a possibly empty list of dynamic rule.
+ * The last dynamic rule has NULL in the "next" field.
+ *
+ * Note that the calculated size is used to bound the
+ * amount of data returned to the user. The rule set may
+ * change between calculating the size and returning the
+ * data in which case we'll just return what fits.
+ */
+ size = static_len; /* size of static rules */
+ if (ipfw_dyn_v) /* add size of dyn.rules */
+ size += (dyn_count * sizeof(ipfw_dyn_rule));
+
+ /*
+ * XXX todo: if the user passes a short length just to know
+ * how much room is needed, do not bother filling up the
+ * buffer, just jump to the sooptcopyout.
+ */
+ buf = malloc(size, M_TEMP, M_WAITOK);
+ error = sooptcopyout(sopt, buf,
+ ipfw_getrules(&layer3_chain, buf, size));
+ free(buf, M_TEMP);
+ break;
+
+ case IP_FW_FLUSH:
+ /*
+ * Normally we cannot release the lock on each iteration.
+ * We could do it here only because we start from the head all
+ * the times so there is no risk of missing some entries.
+ * On the other hand, the risk is that we end up with
+ * a very inconsistent ruleset, so better keep the lock
+ * around the whole cycle.
+ *
+ * XXX this code can be improved by resetting the head of
+ * the list to point to the default rule, and then freeing
+ * the old list without the need for a lock.
+ */
+
+ IPFW_WLOCK(&layer3_chain);
+ layer3_chain.reap = NULL;
+ free_chain(&layer3_chain, 0 /* keep default rule */);
+ rule = layer3_chain.reap;
+ layer3_chain.reap = NULL;
+ IPFW_WUNLOCK(&layer3_chain);
+ if (rule != NULL)
+ reap_rules(rule);
+ break;
+
+ case IP_FW_ADD:
+ rule = malloc(RULE_MAXSIZE, M_TEMP, M_WAITOK);
+ error = sooptcopyin(sopt, rule, RULE_MAXSIZE,
+ sizeof(struct ip_fw) );
+ if (error == 0)
+ error = check_ipfw_struct(rule, sopt->sopt_valsize);
+ if (error == 0) {
+ error = add_rule(&layer3_chain, rule);
+ size = RULESIZE(rule);
+ if (!error && sopt->sopt_dir == SOPT_GET)
+ error = sooptcopyout(sopt, rule, size);
+ }
+ free(rule, M_TEMP);
+ break;
+
+ case IP_FW_DEL:
+ /*
+ * IP_FW_DEL is used for deleting single rules or sets,
+ * and (ab)used to atomically manipulate sets. Argument size
+ * is used to distinguish between the two:
+ * sizeof(u_int32_t)
+ * delete single rule or set of rules,
+ * or reassign rules (or sets) to a different set.
+ * 2*sizeof(u_int32_t)
+ * atomic disable/enable sets.
+ * first u_int32_t contains sets to be disabled,
+ * second u_int32_t contains sets to be enabled.
+ */
+ error = sooptcopyin(sopt, rulenum,
+ 2*sizeof(u_int32_t), sizeof(u_int32_t));
+ if (error)
+ break;
+ size = sopt->sopt_valsize;
+ if (size == sizeof(u_int32_t)) /* delete or reassign */
+ error = del_entry(&layer3_chain, rulenum[0]);
+ else if (size == 2*sizeof(u_int32_t)) /* set enable/disable */
+ set_disable =
+ (set_disable | rulenum[0]) & ~rulenum[1] &
+ ~(1<<RESVD_SET); /* set RESVD_SET always enabled */
+ else
+ error = EINVAL;
+ break;
+
+ case IP_FW_ZERO:
+ case IP_FW_RESETLOG: /* argument is an u_int_32, the rule number */
+ rulenum[0] = 0;
+ if (sopt->sopt_val != 0) {
+ error = sooptcopyin(sopt, rulenum,
+ sizeof(u_int32_t), sizeof(u_int32_t));
+ if (error)
+ break;
+ }
+ error = zero_entry(&layer3_chain, rulenum[0],
+ sopt->sopt_name == IP_FW_RESETLOG);
+ break;
+
+#ifdef radix
+ case IP_FW_TABLE_ADD:
+ {
+ ipfw_table_entry ent;
+
+ error = sooptcopyin(sopt, &ent,
+ sizeof(ent), sizeof(ent));
+ if (error)
+ break;
+ error = add_table_entry(&layer3_chain, ent.tbl,
+ ent.addr, ent.masklen, ent.value);
+ }
+ break;
+
+ case IP_FW_TABLE_DEL:
+ {
+ ipfw_table_entry ent;
+
+ error = sooptcopyin(sopt, &ent,
+ sizeof(ent), sizeof(ent));
+ if (error)
+ break;
+ error = del_table_entry(&layer3_chain, ent.tbl,
+ ent.addr, ent.masklen);
+ }
+ break;
+
+ case IP_FW_TABLE_FLUSH:
+ {
+ u_int16_t tbl;
+
+ error = sooptcopyin(sopt, &tbl,
+ sizeof(tbl), sizeof(tbl));
+ if (error)
+ break;
+ IPFW_WLOCK(&layer3_chain);
+ error = flush_table(&layer3_chain, tbl);
+ IPFW_WUNLOCK(&layer3_chain);
+ }
+ break;
+
+ case IP_FW_TABLE_GETSIZE:
+ {
+ u_int32_t tbl, cnt;
+
+ if ((error = sooptcopyin(sopt, &tbl, sizeof(tbl),
+ sizeof(tbl))))
+ break;
+ IPFW_RLOCK(&layer3_chain);
+ error = count_table(&layer3_chain, tbl, &cnt);
+ IPFW_RUNLOCK(&layer3_chain);
+ if (error)
+ break;
+ error = sooptcopyout(sopt, &cnt, sizeof(cnt));
+ }
+ break;
+
+ case IP_FW_TABLE_LIST:
+ {
+ ipfw_table *tbl;
+
+ if (sopt->sopt_valsize < sizeof(*tbl)) {
+ error = EINVAL;
+ break;
+ }
+ size = sopt->sopt_valsize;
+ tbl = malloc(size, M_TEMP, M_WAITOK);
+ error = sooptcopyin(sopt, tbl, size, sizeof(*tbl));
+ if (error) {
+ free(tbl, M_TEMP);
+ break;
+ }
+ tbl->size = (size - sizeof(*tbl)) /
+ sizeof(ipfw_table_entry);
+ IPFW_RLOCK(&layer3_chain);
+ error = dump_table(&layer3_chain, tbl);
+ IPFW_RUNLOCK(&layer3_chain);
+ if (error) {
+ free(tbl, M_TEMP);
+ break;
+ }
+ error = sooptcopyout(sopt, tbl, size);
+ free(tbl, M_TEMP);
+ }
+ break;
+
+#endif /* radix */
+
+ case IP_FW_NAT_CFG:
+ if (IPFW_NAT_LOADED)
+ error = ipfw_nat_cfg_ptr(sopt);
+ else {
+ printf("IP_FW_NAT_CFG: %s\n",
+ "ipfw_nat not present, please load it");
+ error = EINVAL;
+ }
+ break;
+
+ case IP_FW_NAT_DEL:
+ if (IPFW_NAT_LOADED)
+ error = ipfw_nat_del_ptr(sopt);
+ else {
+ printf("IP_FW_NAT_DEL: %s\n",
+ "ipfw_nat not present, please load it");
+ error = EINVAL;
+ }
+ break;
+
+ case IP_FW_NAT_GET_CONFIG:
+ if (IPFW_NAT_LOADED)
+ error = ipfw_nat_get_cfg_ptr(sopt);
+ else {
+ printf("IP_FW_NAT_GET_CFG: %s\n",
+ "ipfw_nat not present, please load it");
+ error = EINVAL;
+ }
+ break;
+
+ case IP_FW_NAT_GET_LOG:
+ if (IPFW_NAT_LOADED)
+ error = ipfw_nat_get_log_ptr(sopt);
+ else {
+ printf("IP_FW_NAT_GET_LOG: %s\n",
+ "ipfw_nat not present, please load it");
+ error = EINVAL;
+ }
+ break;
+
+ default:
+ printf("ipfw: ipfw_ctl invalid option %d\n", sopt->sopt_name);
+ error = EINVAL;
+ }
+
+ return (error);
+#undef RULE_MAXSIZE
+}
+
+/**
+ * dummynet needs a reference to the default rule, because rules can be
+ * deleted while packets hold a reference to them. When this happens,
+ * dummynet changes the reference to the default rule (it could well be a
+ * NULL pointer, but this way we do not need to check for the special
+ * case, plus here he have info on the default behaviour).
+ */
+struct ip_fw *ip_fw_default_rule;
+
+/*
+ * This procedure is only used to handle keepalives. It is invoked
+ * every dyn_keepalive_period
+ */
+static void
+ipfw_tick(void * __unused unused)
+{
+ struct mbuf *m0, *m, *mnext, **mtailp;
+ int i;
+ ipfw_dyn_rule *q;
+
+ if (dyn_keepalive == 0 || ipfw_dyn_v == NULL || dyn_count == 0)
+ goto done;
+
+ /*
+ * We make a chain of packets to go out here -- not deferring
+ * until after we drop the IPFW dynamic rule lock would result
+ * in a lock order reversal with the normal packet input -> ipfw
+ * call stack.
+ */
+ m0 = NULL;
+ mtailp = &m0;
+ IPFW_DYN_LOCK();
+ for (i = 0 ; i < curr_dyn_buckets ; i++) {
+ for (q = ipfw_dyn_v[i] ; q ; q = q->next ) {
+ if (q->dyn_type == O_LIMIT_PARENT)
+ continue;
+ if (q->id.proto != IPPROTO_TCP)
+ continue;
+ if ( (q->state & BOTH_SYN) != BOTH_SYN)
+ continue;
+ if (TIME_LEQ( time_uptime+dyn_keepalive_interval,
+ q->expire))
+ continue; /* too early */
+ if (TIME_LEQ(q->expire, time_uptime))
+ continue; /* too late, rule expired */
+
+ *mtailp = send_pkt(NULL, &(q->id), q->ack_rev - 1,
+ q->ack_fwd, TH_SYN);
+ if (*mtailp != NULL)
+ mtailp = &(*mtailp)->m_nextpkt;
+ *mtailp = send_pkt(NULL, &(q->id), q->ack_fwd - 1,
+ q->ack_rev, 0);
+ if (*mtailp != NULL)
+ mtailp = &(*mtailp)->m_nextpkt;
+ }
+ }
+ IPFW_DYN_UNLOCK();
+ for (m = mnext = m0; m != NULL; m = mnext) {
+ mnext = m->m_nextpkt;
+ m->m_nextpkt = NULL;
+ ip_output(m, NULL, NULL, 0, NULL, NULL);
+ }
+done:
+ callout_reset(&ipfw_timeout, dyn_keepalive_period*hz, ipfw_tick, NULL);
+}
+
+int
+ipfw_init(void)
+{
+ struct ip_fw default_rule;
+ int error;
+
+#ifdef INET6
+ /* Setup IPv6 fw sysctl tree. */
+ sysctl_ctx_init(&ip6_fw_sysctl_ctx);
+ ip6_fw_sysctl_tree = SYSCTL_ADD_NODE(&ip6_fw_sysctl_ctx,
+ SYSCTL_STATIC_CHILDREN(_net_inet6_ip6), OID_AUTO, "fw",
+ CTLFLAG_RW | CTLFLAG_SECURE, 0, "Firewall");
+ SYSCTL_ADD_PROC(&ip6_fw_sysctl_ctx, SYSCTL_CHILDREN(ip6_fw_sysctl_tree),
+ OID_AUTO, "enable", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3,
+ &fw6_enable, 0, ipfw_chg_hook, "I", "Enable ipfw+6");
+ SYSCTL_ADD_INT(&ip6_fw_sysctl_ctx, SYSCTL_CHILDREN(ip6_fw_sysctl_tree),
+ OID_AUTO, "deny_unknown_exthdrs", CTLFLAG_RW | CTLFLAG_SECURE,
+ &fw_deny_unknown_exthdrs, 0,
+ "Deny packets with unknown IPv6 Extension Headers");
+#endif
+
+ layer3_chain.rules = NULL;
+ IPFW_LOCK_INIT(&layer3_chain);
+ ipfw_dyn_rule_zone = uma_zcreate("IPFW dynamic rule",
+ sizeof(ipfw_dyn_rule), NULL, NULL, NULL, NULL,
+ UMA_ALIGN_PTR, 0);
+ IPFW_DYN_LOCK_INIT();
+ callout_init(&ipfw_timeout, CALLOUT_MPSAFE);
+
+ bzero(&default_rule, sizeof default_rule);
+
+ default_rule.act_ofs = 0;
+ default_rule.rulenum = IPFW_DEFAULT_RULE;
+ default_rule.cmd_len = 1;
+ default_rule.set = RESVD_SET;
+
+ default_rule.cmd[0].len = 1;
+ default_rule.cmd[0].opcode =
+#ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
+ 1 ? O_ACCEPT :
+#endif
+ O_DENY;
+
+ error = add_rule(&layer3_chain, &default_rule);
+ if (error != 0) {
+ printf("ipfw2: error %u initializing default rule "
+ "(support disabled)\n", error);
+ IPFW_DYN_LOCK_DESTROY();
+ IPFW_LOCK_DESTROY(&layer3_chain);
+ uma_zdestroy(ipfw_dyn_rule_zone);
+ return (error);
+ }
+
+ ip_fw_default_rule = layer3_chain.rules;
+ printf("ipfw2 "
+#ifdef INET6
+ "(+ipv6) "
+#endif
+ "initialized, divert %s, nat %s, "
+ "rule-based forwarding "
+#ifdef IPFIREWALL_FORWARD
+ "enabled, "
+#else
+ "disabled, "
+#endif
+ "default to %s, logging ",
+#ifdef IPDIVERT
+ "enabled",
+#else
+ "loadable",
+#endif
+#ifdef IPFIREWALL_NAT
+ "enabled",
+#else
+ "loadable",
+#endif
+
+ default_rule.cmd[0].opcode == O_ACCEPT ? "accept" : "deny");
+
+#ifdef IPFIREWALL_VERBOSE
+ fw_verbose = 1;
+#endif
+#ifdef IPFIREWALL_VERBOSE_LIMIT
+ verbose_limit = IPFIREWALL_VERBOSE_LIMIT;
+#endif
+ if (fw_verbose == 0)
+ printf("disabled\n");
+ else if (verbose_limit == 0)
+ printf("unlimited\n");
+ else
+ printf("limited to %d packets/entry by default\n",
+ verbose_limit);
+
+ error = init_tables(&layer3_chain);
+ if (error) {
+ IPFW_DYN_LOCK_DESTROY();
+ IPFW_LOCK_DESTROY(&layer3_chain);
+ uma_zdestroy(ipfw_dyn_rule_zone);
+ return (error);
+ }
+ ip_fw_ctl_ptr = ipfw_ctl;
+ ip_fw_chk_ptr = ipfw_chk;
+ callout_reset(&ipfw_timeout, hz, ipfw_tick, NULL);
+ LIST_INIT(&layer3_chain.nat);
+ return (0);
+}
+
+void
+ipfw_destroy(void)
+{
+ struct ip_fw *reap;
+
+ ip_fw_chk_ptr = NULL;
+ ip_fw_ctl_ptr = NULL;
+ callout_drain(&ipfw_timeout);
+ IPFW_WLOCK(&layer3_chain);
+ flush_tables(&layer3_chain);
+ layer3_chain.reap = NULL;
+ free_chain(&layer3_chain, 1 /* kill default rule */);
+ reap = layer3_chain.reap, layer3_chain.reap = NULL;
+ IPFW_WUNLOCK(&layer3_chain);
+ if (reap != NULL)
+ reap_rules(reap);
+ IPFW_DYN_LOCK_DESTROY();
+ uma_zdestroy(ipfw_dyn_rule_zone);
+ if (ipfw_dyn_v != NULL)
+ free(ipfw_dyn_v, M_IPFW);
+ IPFW_LOCK_DESTROY(&layer3_chain);
+
+#ifdef INET6
+ /* Free IPv6 fw sysctl tree. */
+ sysctl_ctx_free(&ip6_fw_sysctl_ctx);
+#endif
+
+ printf("IP firewall unloaded\n");
+}
git://git.onelab.eu / ipfw.git / blobdiff