diff --git a/sys/modules/ipfw/Makefile b/sys/modules/ipfw/Makefile index 81ce838085d9..ec9b3cc49c1a 100644 --- a/sys/modules/ipfw/Makefile +++ b/sys/modules/ipfw/Makefile @@ -1,31 +1,31 @@ # $FreeBSD$ .include .PATH: ${.CURDIR}/../../netinet/ipfw KMOD= ipfw SRCS= ip_fw2.c ip_fw_pfil.c SRCS+= ip_fw_dynamic.c ip_fw_log.c SRCS+= ip_fw_sockopt.c ip_fw_table.c -SRCS+= opt_inet6.h opt_ipsec.h +SRCS+= opt_inet6.h opt_ipfw.h opt_ipsec.h CFLAGS+= -DIPFIREWALL CFLAGS+= -I${.CURDIR}/../../contrib/pf # #If you want it verbose #CFLAGS+= -DIPFIREWALL_VERBOSE #CFLAGS+= -DIPFIREWALL_VERBOSE_LIMIT=100 # #If you want it to pass all packets by default #CFLAGS+= -DIPFIREWALL_DEFAULT_TO_ACCEPT # .if !defined(KERNBUILDDIR) .if ${MK_INET6_SUPPORT} != "no" opt_inet6.h: echo "#define INET6 1" > ${.TARGET} .endif .endif .include diff --git a/sys/netinet/ipfw/ip_fw2.c b/sys/netinet/ipfw/ip_fw2.c index c3123dfa11b0..619ce6b91e5b 100644 --- a/sys/netinet/ipfw/ip_fw2.c +++ b/sys/netinet/ipfw/ip_fw2.c @@ -1,2728 +1,2728 @@ /*- * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); /* * The FreeBSD IP packet firewall, main file */ -#if !defined(KLD_MODULE) #include "opt_ipfw.h" +#if !defined(KLD_MODULE) #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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* for ETHERTYPE_IP */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #include #include #endif #include /* XXX for in_cksum */ #ifdef MAC #include #endif /* * static variables followed by global ones. * All ipfw global variables are here. */ /* ipfw_vnet_ready controls when we are open for business */ static VNET_DEFINE(int, ipfw_vnet_ready) = 0; #define V_ipfw_vnet_ready VNET(ipfw_vnet_ready) static VNET_DEFINE(int, fw_deny_unknown_exthdrs); #define V_fw_deny_unknown_exthdrs VNET(fw_deny_unknown_exthdrs) static VNET_DEFINE(int, fw_permit_single_frag6) = 1; #define V_fw_permit_single_frag6 VNET(fw_permit_single_frag6) #ifdef IPFIREWALL_DEFAULT_TO_ACCEPT static int default_to_accept = 1; #else static int default_to_accept; #endif VNET_DEFINE(int, autoinc_step); VNET_DEFINE(int, fw_one_pass) = 1; /* * Each rule belongs to one of 32 different sets (0..31). * The variable set_disable contains one bit per set. * If the bit is set, all rules in the corresponding set * are disabled. Set RESVD_SET(31) is reserved for the default rule * and rules that are not deleted by the flush command, * and CANNOT be disabled. * Rules in set RESVD_SET can only be deleted individually. */ VNET_DEFINE(u_int32_t, set_disable); #define V_set_disable VNET(set_disable) VNET_DEFINE(int, fw_verbose); /* counter for ipfw_log(NULL...) */ VNET_DEFINE(u_int64_t, norule_counter); VNET_DEFINE(int, verbose_limit); /* layer3_chain contains the list of rules for layer 3 */ VNET_DEFINE(struct ip_fw_chain, layer3_chain); ipfw_nat_t *ipfw_nat_ptr = NULL; struct cfg_nat *(*lookup_nat_ptr)(struct nat_list *, int); ipfw_nat_cfg_t *ipfw_nat_cfg_ptr; ipfw_nat_cfg_t *ipfw_nat_del_ptr; ipfw_nat_cfg_t *ipfw_nat_get_cfg_ptr; ipfw_nat_cfg_t *ipfw_nat_get_log_ptr; #ifdef SYSCTL_NODE uint32_t dummy_def = IPFW_DEFAULT_RULE; uint32_t dummy_tables_max = IPFW_TABLES_MAX; SYSBEGIN(f3) SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall"); SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, one_pass, CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_one_pass), 0, "Only do a single pass through ipfw when using dummynet(4)"); SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, autoinc_step, CTLFLAG_RW, &VNET_NAME(autoinc_step), 0, "Rule number auto-increment step"); SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, verbose, CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_verbose), 0, "Log matches to ipfw rules"); SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit, CTLFLAG_RW, &VNET_NAME(verbose_limit), 0, "Set upper limit of matches of ipfw rules logged"); SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, default_rule, CTLFLAG_RD, &dummy_def, 0, "The default/max possible rule number."); SYSCTL_UINT(_net_inet_ip_fw, OID_AUTO, tables_max, CTLFLAG_RD, &dummy_tables_max, 0, "The maximum number of tables."); SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, default_to_accept, CTLFLAG_RDTUN, &default_to_accept, 0, "Make the default rule accept all packets."); TUNABLE_INT("net.inet.ip.fw.default_to_accept", &default_to_accept); SYSCTL_VNET_INT(_net_inet_ip_fw, OID_AUTO, static_count, CTLFLAG_RD, &VNET_NAME(layer3_chain.n_rules), 0, "Number of static rules"); #ifdef INET6 SYSCTL_DECL(_net_inet6_ip6); SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall"); SYSCTL_VNET_INT(_net_inet6_ip6_fw, OID_AUTO, deny_unknown_exthdrs, CTLFLAG_RW | CTLFLAG_SECURE, &VNET_NAME(fw_deny_unknown_exthdrs), 0, "Deny packets with unknown IPv6 Extension Headers"); SYSCTL_VNET_INT(_net_inet6_ip6_fw, OID_AUTO, permit_single_frag6, CTLFLAG_RW | CTLFLAG_SECURE, &VNET_NAME(fw_permit_single_frag6), 0, "Permit single packet IPv6 fragments"); #endif /* INET6 */ SYSEND #endif /* SYSCTL_NODE */ /* * Some macros used in the various matching options. * L3HDR maps an ipv4 pointer into a layer3 header pointer of type T * Other macros just cast void * into the appropriate type */ #define L3HDR(T, ip) ((T *)((u_int32_t *)(ip) + (ip)->ip_hl)) #define TCP(p) ((struct tcphdr *)(p)) #define SCTP(p) ((struct sctphdr *)(p)) #define UDP(p) ((struct udphdr *)(p)) #define ICMP(p) ((struct icmphdr *)(p)) #define ICMP6(p) ((struct icmp6_hdr *)(p)) static __inline int icmptype_match(struct icmphdr *icmp, ipfw_insn_u32 *cmd) { int type = icmp->icmp_type; return (type <= ICMP_MAXTYPE && (cmd->d[0] & (1<icmp_type; return (type <= ICMP_MAXTYPE && (TT & (1<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 { #ifdef __FreeBSD__ /* and OSX too ? */ struct ifaddr *ia; if_addr_rlock(ifp); 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) { if_addr_runlock(ifp); return(1); /* match */ } } if_addr_runlock(ifp); #endif /* __FreeBSD__ */ } return(0); /* no match, fail ... */ } /* * The verify_path function checks if a route to the src exists and * if it is reachable via ifp (when provided). * * The 'verrevpath' option checks that the interface that an IP packet * arrives on is the same interface that traffic destined for the * packet's source address would be routed out of. * The 'versrcreach' option just checks that the source address is * reachable via any route (except default) in the routing table. * These two are a measure to block forged packets. This is also * commonly known as "anti-spoofing" or Unicast Reverse Path * Forwarding (Unicast RFP) in Cisco-ese. The name of the knobs * is purposely reminiscent of the Cisco IOS command, * * ip verify unicast reverse-path * ip verify unicast source reachable-via any * * which implements the same functionality. But note that the syntax * is misleading, and the check may be performed on all IP packets * whether unicast, multicast, or broadcast. */ static int verify_path(struct in_addr src, struct ifnet *ifp, u_int fib) { #ifndef __FreeBSD__ return 0; #else 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, 0, 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 /* __FreeBSD__ */ } #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, &V_ifnet, if_link) { if_addr_rlock(mdc); TAILQ_FOREACH(mdc2, &mdc->if_addrhead, ifa_link) { 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)) { if_addr_runlock(mdc); return 1; } } } if_addr_runlock(mdc); } 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, 0); 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 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 = (struct tcphdr *)((char *)ip6 + hlen); if ((tcp->th_flags & TH_RST) == 0) { struct mbuf *m0; m0 = ipfw_send_pkt(args->m, &(args->f_id), ntohl(tcp->th_seq), ntohl(tcp->th_ack), tcp->th_flags | TH_RST); if (m0 != NULL) ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL); } FREE_PKT(m); } else if (code != ICMP6_UNREACH_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 FREE_PKT(m); args->m = NULL; } #endif /* INET6 */ /* * sends a reject message, consuming the mbuf passed as an argument. */ static void send_reject(struct ip_fw_args *args, int code, int iplen, 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(). */ SET_HOST_IPLEN(ip); 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 = ipfw_send_pkt(args->m, &(args->f_id), ntohl(tcp->th_seq), ntohl(tcp->th_ack), tcp->th_flags | TH_RST); if (m != NULL) ip_output(m, NULL, NULL, 0, NULL, NULL); } FREE_PKT(args->m); } else FREE_PKT(args->m); args->m = NULL; } /* * Support for uid/gid/jail lookup. These tests are expensive * (because we may need to look into the list of active sockets) * so we cache the results. ugid_lookupp is 0 if we have not * yet done a lookup, 1 if we succeeded, and -1 if we tried * and failed. The function always returns the match value. * We could actually spare the variable and use *uc, setting * it to '(void *)check_uidgid if we have no info, NULL if * we tried and failed, or any other value if successful. */ static int check_uidgid(ipfw_insn_u32 *insn, struct ip_fw_args *args, int *ugid_lookupp, struct ucred **uc) { #ifndef __FreeBSD__ /* XXX */ return cred_check(insn, proto, oif, dst_ip, dst_port, src_ip, src_port, (struct bsd_ucred *)uc, ugid_lookupp, ((struct mbuf *)inp)->m_skb); #else /* FreeBSD */ struct in_addr src_ip, dst_ip; struct inpcbinfo *pi; struct ipfw_flow_id *id; struct inpcb *pcb, *inp; struct ifnet *oif; int lookupflags; int match; id = &args->f_id; inp = args->inp; oif = args->oif; /* * Check to see if the UDP or TCP stack supplied us with * the PCB. If so, rather then holding a lock and looking * up the PCB, we can use the one that was supplied. */ if (inp && *ugid_lookupp == 0) { INP_LOCK_ASSERT(inp); if (inp->inp_socket != NULL) { *uc = crhold(inp->inp_cred); *ugid_lookupp = 1; } else *ugid_lookupp = -1; } /* * If we have already been here and the packet has no * PCB entry associated with it, then we can safely * assume that this is a no match. */ if (*ugid_lookupp == -1) return (0); if (id->proto == IPPROTO_TCP) { lookupflags = 0; pi = &V_tcbinfo; } else if (id->proto == IPPROTO_UDP) { lookupflags = INPLOOKUP_WILDCARD; pi = &V_udbinfo; } else return 0; lookupflags |= INPLOOKUP_RLOCKPCB; match = 0; if (*ugid_lookupp == 0) { if (id->addr_type == 6) { #ifdef INET6 if (oif == NULL) pcb = in6_pcblookup_mbuf(pi, &id->src_ip6, htons(id->src_port), &id->dst_ip6, htons(id->dst_port), lookupflags, oif, args->m); else pcb = in6_pcblookup_mbuf(pi, &id->dst_ip6, htons(id->dst_port), &id->src_ip6, htons(id->src_port), lookupflags, oif, args->m); #else *ugid_lookupp = -1; return (0); #endif } else { src_ip.s_addr = htonl(id->src_ip); dst_ip.s_addr = htonl(id->dst_ip); if (oif == NULL) pcb = in_pcblookup_mbuf(pi, src_ip, htons(id->src_port), dst_ip, htons(id->dst_port), lookupflags, oif, args->m); else pcb = in_pcblookup_mbuf(pi, dst_ip, htons(id->dst_port), src_ip, htons(id->src_port), lookupflags, oif, args->m); } if (pcb != NULL) { INP_RLOCK_ASSERT(pcb); *uc = crhold(pcb->inp_cred); *ugid_lookupp = 1; INP_RUNLOCK(pcb); } if (*ugid_lookupp == 0) { /* * We tried and failed, set the variable to -1 * so we will not try again on this packet. */ *ugid_lookupp = -1; return (0); } } if (insn->o.opcode == O_UID) match = ((*uc)->cr_uid == (uid_t)insn->d[0]); else if (insn->o.opcode == O_GID) match = groupmember((gid_t)insn->d[0], *uc); else if (insn->o.opcode == O_JAIL) match = ((*uc)->cr_prison->pr_id == (int)insn->d[0]); return (match); #endif /* __FreeBSD__ */ } /* * Helper function to set args with info on the rule after the matching * one. slot is precise, whereas we guess rule_id as they are * assigned sequentially. */ static inline void set_match(struct ip_fw_args *args, int slot, struct ip_fw_chain *chain) { args->rule.chain_id = chain->id; args->rule.slot = slot + 1; /* we use 0 as a marker */ args->rule.rule_id = 1 + chain->map[slot]->id; args->rule.rulenum = chain->map[slot]->rulenum; } /* * 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, 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, 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->next_hop6 IPv6 next hop we are forwarding to (out). * args->f_id Addresses grabbed from the packet (out) * args->rule.info a cookie depending on rule action * * Return value: * * IP_FW_PASS the packet must be accepted * IP_FW_DENY the packet must be dropped * IP_FW_DIVERT divert packet, port in m_tag * IP_FW_TEE tee packet, port in m_tag * IP_FW_DUMMYNET to dummynet, pipe in args->cookie * IP_FW_NETGRAPH into netgraph, cookie args->cookie * args->rule contains the matching rule, * args->rule.info has additional information. * */ int ipfw_chk(struct ip_fw_args *args) { /* * Local variables holding state while processing a packet: * * IMPORTANT NOTE: to speed up the processing of rules, there * are some assumption on the values of the variables, which * are documented here. Should you change them, please check * the implementation of the various instructions to make sure * that they still work. * * 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. */ #ifndef __FreeBSD__ struct bsd_ucred ucred_cache; #else struct ucred *ucred_cache = NULL; #endif int ucred_lookup = 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; int f_pos = 0; /* index of current rule in the array */ 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|ip6f_mf == 0 means there is no Fragment Header * or there is a single packet fragement (fragement header added * without needed). We will treat a single packet fragment as if * there was no fragment header (or log/block depending on the * V_fw_permit_single_frag6 sysctl setting). */ u_short offset = 0; u_short ip6f_mf = 0; /* * Local copies of addresses. They are only valid if we have * an IP packet. * * proto The protocol. Set to 0 for non-ip packets, * or to the protocol read from the packet otherwise. * proto != 0 means that we have an IPv4 packet. * * src_port, dst_port port numbers, in HOST format. Only * valid for TCP and UDP packets. * * src_ip, dst_ip ip addresses, in NETWORK format. * Only valid for IPv4 packets. */ uint8_t proto; uint16_t src_port = 0, dst_port = 0; /* NOTE: host format */ struct in_addr src_ip, dst_ip; /* NOTE: network format */ uint16_t iplen=0; int pktlen; uint16_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 = &V_layer3_chain; /* * We store in ulp a pointer to the upper layer protocol header. * In the ipv4 case this is easy to determine from the header, * but for ipv6 we might have some additional headers in the middle. * ulp is NULL if not found. */ void *ulp = NULL; /* upper layer protocol pointer. */ /* XXX ipv6 variables */ int is_ipv6 = 0; uint8_t icmp6_type = 0; uint16_t ext_hd = 0; /* bits vector for extension header filtering */ /* end of ipv6 variables */ int is_ipv4 = 0; int done = 0; /* flag to exit the outer loop */ if (m->m_flags & M_SKIP_FIREWALL || (! V_ipfw_vnet_ready)) 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) PULLUP_LEN(_len, p, sizeof(T)) #define PULLUP_LEN(_len, p, T) \ do { \ int x = (_len) + T; \ if ((m)->m_len < x) { \ args->m = m = m_pullup(m, x); \ if (m == NULL) \ 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 && offset == 0) { switch (proto) { case IPPROTO_ICMPV6: PULLUP_TO(hlen, ulp, struct icmp6_hdr); icmp6_type = 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; /* save flags for dynamic rules */ 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: if (V_fw_verbose) printf("IPFW2: IPV6 - Unknown " "Routing Header type(%d)\n", ((struct ip6_rthdr *) ulp)->ip6r_type); if (V_fw_deny_unknown_exthdrs) return (IP_FW_DENY); break; } ext_hd |= EXT_ROUTING; hlen += (((struct ip6_rthdr *)ulp)->ip6r_len + 1) << 3; proto = ((struct ip6_rthdr *)ulp)->ip6r_nxt; ulp = NULL; break; case IPPROTO_FRAGMENT: /* RFC 2460 */ PULLUP_TO(hlen, ulp, struct ip6_frag); ext_hd |= EXT_FRAGMENT; hlen += sizeof (struct ip6_frag); proto = ((struct ip6_frag *)ulp)->ip6f_nxt; offset = ((struct ip6_frag *)ulp)->ip6f_offlg & IP6F_OFF_MASK; ip6f_mf = ((struct ip6_frag *)ulp)->ip6f_offlg & IP6F_MORE_FRAG; if (V_fw_permit_single_frag6 == 0 && offset == 0 && ip6f_mf == 0) { if (V_fw_verbose) printf("IPFW2: IPV6 - Invalid " "Fragment Header\n"); if (V_fw_deny_unknown_exthdrs) return (IP_FW_DENY); break; } args->f_id.extra = ntohl(((struct ip6_frag *)ulp)->ip6f_ident); ulp = NULL; break; case IPPROTO_DSTOPTS: /* RFC 2460 */ PULLUP_TO(hlen, ulp, struct ip6_hbh); ext_hd |= EXT_DSTOPTS; hlen += (((struct ip6_hbh *)ulp)->ip6h_len + 1) << 3; proto = ((struct ip6_hbh *)ulp)->ip6h_nxt; ulp = NULL; break; case IPPROTO_AH: /* RFC 2402 */ PULLUP_TO(hlen, ulp, struct ip6_ext); ext_hd |= EXT_AH; hlen += (((struct ip6_ext *)ulp)->ip6e_len + 2) << 2; proto = ((struct ip6_ext *)ulp)->ip6e_nxt; ulp = NULL; break; case IPPROTO_ESP: /* RFC 2406 */ PULLUP_TO(hlen, ulp, uint32_t); /* SPI, Seq# */ /* Anything past Seq# is variable length and * data past this ext. header is encrypted. */ ext_hd |= EXT_ESP; break; case IPPROTO_NONE: /* RFC 2460 */ /* * Packet ends here, and IPv6 header has * already been pulled up. If ip6e_len!=0 * then octets must be ignored. */ ulp = ip; /* non-NULL to get out of loop. */ break; case IPPROTO_OSPFIGP: /* XXX OSPF header check? */ PULLUP_TO(hlen, ulp, struct ip6_ext); break; case IPPROTO_PIM: /* XXX PIM header check? */ PULLUP_TO(hlen, ulp, struct pim); break; case IPPROTO_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: if (V_fw_verbose) printf("IPFW2: IPV6 - Unknown " "Extension Header(%d), ext_hd=%x\n", proto, ext_hd); if (V_fw_deny_unknown_exthdrs) return (IP_FW_DENY); PULLUP_TO(hlen, ulp, struct ip6_ext); break; } /*switch */ } 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; offset = ntohs(ip->ip_off) & IP_OFFMASK; iplen = ntohs(ip->ip_len); pktlen = iplen < pktlen ? iplen : 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; /* save flags for dynamic rules */ 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_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); if (! V_ipfw_vnet_ready) { /* shutting down, leave NOW. */ IPFW_RUNLOCK(chain); return (IP_FW_PASS); /* accept */ } if (args->rule.slot) { /* * Packet has already been tagged as a result of a previous * match on rule args->rule aka args->rule_id (PIPE, QUEUE, * REASS, NETGRAPH, DIVERT/TEE...) * Validate the slot and continue from the next one * if still present, otherwise do a lookup. */ f_pos = (args->rule.chain_id == chain->id) ? args->rule.slot : ipfw_find_rule(chain, args->rule.rulenum, args->rule.rule_id); } else { f_pos = 0; } /* * Now scan the rules, and parse microinstructions for each rule. * We have two nested loops and an inner switch. Sometimes we * need to break out of one or both loops, or re-enter one of * the loops with updated variables. Loop variables are: * * f_pos (outer loop) points to the current rule. * On output it points to the matching rule. * done (outer loop) is used as a flag to break the loop. * l (inner loop) residual length of current rule. * cmd points to the current microinstruction. * * We break the inner loop by setting l=0 and possibly * cmdlen=0 if we don't want to advance cmd. * We break the outer loop by setting done=1 * We can restart the inner loop by setting l>0 and f_pos, f, cmd * as needed. */ for (; f_pos < chain->n_rules; f_pos++) { ipfw_insn *cmd; uint32_t tablearg = 0; int l, cmdlen, skip_or; /* skip rest of OR block */ struct ip_fw *f; f = chain->map[f_pos]; if (V_set_disable & (1 << f->set) ) continue; skip_or = 0; for (l = f->cmd_len, cmd = f->cmd ; l > 0 ; l -= cmdlen, cmd += cmdlen) { int match; /* * check_body is a jump target used when we find a * CHECK_STATE, and need to jump to the body of * the target rule. */ /* check_body: */ cmdlen = F_LEN(cmd); /* * An OR block (insn_1 || .. || insn_n) has the * F_OR bit set in all but the last instruction. * The first match will set "skip_or", and cause * the following instructions to be skipped until * past the one with the F_OR bit clear. */ if (skip_or) { /* skip this instruction */ if ((cmd->len & F_OR) == 0) skip_or = 0; /* next one is good */ continue; } match = 0; /* set to 1 if we succeed */ switch (cmd->opcode) { /* * The first set of opcodes compares the packet's * fields with some pattern, setting 'match' if a * match is found. At the end of the loop there is * logic to deal with F_NOT and F_OR flags associated * with the opcode. */ case O_NOP: match = 1; break; case O_FORWARD_MAC: printf("ipfw: opcode %d unimplemented\n", cmd->opcode); break; case O_GID: case O_UID: case O_JAIL: /* * We only check offset == 0 && proto != 0, * as this ensures that we have a * packet with the ports info. */ if (offset != 0) break; if (proto == IPPROTO_TCP || proto == IPPROTO_UDP) match = check_uidgid( (ipfw_insn_u32 *)cmd, args, &ucred_lookup, #ifdef __FreeBSD__ &ucred_cache); #else (void *)&ucred_cache); #endif break; case O_RECV: match = iface_match(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: { /* For diverted packets, args->rule.info * contains the divert port (in host format) * reason and direction. */ uint32_t i = args->rule.info; match = (i&IPFW_IS_MASK) == IPFW_IS_DIVERT && cmd->arg1 & ((i & IPFW_INFO_IN) ? 1 : 2); } 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 key = (cmd->opcode == O_IP_DST_LOOKUP) ? dst_ip.s_addr : src_ip.s_addr; uint32_t v = 0; if (cmdlen > F_INSN_SIZE(ipfw_insn_u32)) { /* generic lookup. The key must be * in 32bit big-endian format. */ v = ((ipfw_insn_u32 *)cmd)->d[1]; if (v == 0) key = dst_ip.s_addr; else if (v == 1) key = src_ip.s_addr; else if (v == 6) /* dscp */ key = (ip->ip_tos >> 2) & 0x3f; else if (offset != 0) break; else if (proto != IPPROTO_TCP && proto != IPPROTO_UDP) break; else if (v == 2) key = htonl(dst_port); else if (v == 3) key = htonl(src_port); else if (v == 4 || v == 5) { check_uidgid( (ipfw_insn_u32 *)cmd, args, &ucred_lookup, #ifdef __FreeBSD__ &ucred_cache); if (v == 4 /* O_UID */) key = ucred_cache->cr_uid; else if (v == 5 /* O_JAIL */) key = ucred_cache->cr_prison->pr_id; #else /* !__FreeBSD__ */ (void *)&ucred_cache); if (v ==4 /* O_UID */) key = ucred_cache.uid; else if (v == 5 /* O_JAIL */) key = ucred_cache.xid; #endif /* !__FreeBSD__ */ key = htonl(key); } else break; } match = ipfw_lookup_table(chain, cmd->arg1, key, &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; } #ifdef INET6 /* FALLTHROUGH */ case O_IP6_SRC_ME: match= is_ipv6 && search_ip6_addr_net(&args->f_id.src_ip6); #endif break; case O_IP_DST_SET: case O_IP_SRC_SET: if (is_ipv4) { u_int32_t *d = (u_int32_t *)(cmd+1); u_int32_t addr = cmd->opcode == O_IP_DST_SET ? args->f_id.dst_ip : args->f_id.src_ip; if (addr < d[0]) break; addr -= d[0]; /* subtract base */ match = (addr < cmd->arg1) && ( d[ 1 + (addr>>5)] & (1<<(addr & 0x1f)) ); } break; case O_IP_DST: match = is_ipv4 && (((ipfw_insn_ip *)cmd)->addr.s_addr == dst_ip.s_addr); break; case O_IP_DST_ME: if (is_ipv4) { struct ifnet *tif; INADDR_TO_IFP(dst_ip, tif); match = (tif != NULL); break; } #ifdef INET6 /* FALLTHROUGH */ case O_IP6_DST_ME: match= is_ipv6 && search_ip6_addr_net(&args->f_id.dst_ip6); #endif break; case O_IP_SRCPORT: case O_IP_DSTPORT: /* * offset == 0 && proto != 0 is enough * to guarantee that we have a * packet with port info. */ if ((proto==IPPROTO_UDP || proto==IPPROTO_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 = iplen; else if (cmd->opcode == O_IPTTL) x = ip->ip_ttl; else /* must be IPID */ x = ntohs(ip->ip_id); if (cmdlen == 1) { match = (cmd->arg1 == x); break; } /* otherwise we have ranges */ p = ((ipfw_insn_u16 *)cmd)->ports; i = cmdlen - 1; for (; !match && i>0; i--, p += 2) match = (x >= p[0] && x <= p[1]); } break; case O_IPPRECEDENCE: match = (is_ipv4 && (cmd->arg1 == (ip->ip_tos & 0xe0)) ); break; case O_IPTOS: match = (is_ipv4 && flags_match(cmd, ip->ip_tos)); break; case O_TCPDATALEN: if (proto == IPPROTO_TCP && offset == 0) { struct tcphdr *tcp; uint16_t x; uint16_t *p; int i; tcp = TCP(ulp); x = iplen - ((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: PULLUP_LEN(hlen, ulp, (TCP(ulp)->th_off << 2)); 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; at->hdr = ip; break; } case O_LOG: ipfw_log(f, hlen, args, m, oif, offset | ip6f_mf, tablearg, ip); match = 1; break; case O_PROB: match = (random()<((ipfw_insn_u32 *)cmd)->d[0]); break; case O_VERREVPATH: /* Outgoing packets automatically pass/match */ match = ((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; 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_FLOW6ID: match = is_ipv6 && flow6id_match(args->f_id.flow_id6, (ipfw_insn_u32 *) cmd); break; case O_EXT_HDR: match = is_ipv6 && (ext_hd & ((ipfw_insn *) cmd)->arg1); break; case O_IP6: match = is_ipv6; break; #endif case O_IP4: match = is_ipv4; break; case O_TAG: { struct m_tag *mtag; uint32_t tag = (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); match = 0; } else { if (mtag == NULL) { mtag = m_tag_alloc( MTAG_IPFW, tag, 0, M_NOWAIT); if (mtag != NULL) m_tag_prepend(m, mtag); } match = 1; } break; } case O_FIB: /* try match the specified fib */ if (args->f_id.fib == cmd->arg1) match = 1; break; case O_SOCKARG: { struct inpcb *inp = args->inp; struct inpcbinfo *pi; if (is_ipv6) /* XXX can we remove this ? */ break; if (proto == IPPROTO_TCP) pi = &V_tcbinfo; else if (proto == IPPROTO_UDP) pi = &V_udbinfo; else break; /* * XXXRW: so_user_cookie should almost * certainly be inp_user_cookie? */ /* For incomming packet, lookup up the inpcb using the src/dest ip/port tuple */ if (inp == NULL) { inp = in_pcblookup(pi, src_ip, htons(src_port), dst_ip, htons(dst_port), INPLOOKUP_RLOCKPCB, NULL); if (inp != NULL) { tablearg = inp->inp_socket->so_user_cookie; if (tablearg) match = 1; INP_RUNLOCK(inp); } } else { if (inp->inp_socket) { tablearg = inp->inp_socket->so_user_cookie; if (tablearg) match = 1; } } break; } case O_TAGGED: { struct m_tag *mtag; 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; } /* * The second set of opcodes represents 'actions', * i.e. the terminal part of a rule once the packet * matches all previous patterns. * Typically there is only one action for each rule, * and the opcode is stored at the end of the rule * (but there are exceptions -- see below). * * In general, here we set retval and terminate the * outer loop (would be a 'break 3' in some language, * but we need to set l=0, done=1) * * Exceptions: * O_COUNT and O_SKIPTO actions: * instead of terminating, we jump to the next rule * (setting l=0), or to the SKIPTO target (setting * f/f_len, cmd and l as needed), respectively. * * O_TAG, O_LOG and O_ALTQ action parameters: * perform some action and set match = 1; * * O_LIMIT and O_KEEP_STATE: these opcodes are * not real 'actions', and are stored right * before the 'action' part of the rule. * These opcodes try to install an entry in the * state tables; if successful, we continue with * the next opcode (match=1; break;), otherwise * the packet must be dropped (set retval, * break loops with l=0, done=1) * * O_PROBE_STATE and O_CHECK_STATE: these opcodes * cause a lookup of the state table, and a jump * to the 'action' part of the parent rule * if an entry is found, or * (CHECK_STATE only) a jump to the next rule if * the entry is not found. * The result of the lookup is cached so that * further instances of these opcodes become NOPs. * The jump to the next rule is done by setting * l=0, cmdlen=0. */ case O_LIMIT: case O_KEEP_STATE: if (ipfw_install_state(f, (ipfw_insn_limit *)cmd, args, tablearg)) { /* error or limit violation */ retval = IP_FW_DENY; l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ } match = 1; break; case O_PROBE_STATE: case O_CHECK_STATE: /* * dynamic rules are checked at the first * keep-state or check-state occurrence, * with the result being stored in dyn_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 = ipfw_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 by setting * f, cmd, l and clearing cmdlen. */ q->pcnt++; q->bcnt += pktlen; /* XXX we would like to have f_pos * readily accessible in the dynamic * rule, instead of having to * lookup q->rule. */ f = q->rule; f_pos = ipfw_find_rule(chain, f->rulenum, f->id); cmd = ACTION_PTR(f); l = f->cmd_len - f->act_ofs; ipfw_dyn_unlock(); cmdlen = 0; match = 1; break; } /* * Dynamic entry not found. If CHECK_STATE, * skip to next rule, if PROBE_STATE just * ignore and continue with next opcode. */ if (cmd->opcode == O_CHECK_STATE) l = 0; /* exit inner loop */ match = 1; break; case O_ACCEPT: retval = 0; /* accept */ l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ break; case O_PIPE: case O_QUEUE: set_match(args, f_pos, chain); args->rule.info = (cmd->arg1 == IP_FW_TABLEARG) ? tablearg : cmd->arg1; if (cmd->opcode == O_PIPE) args->rule.info |= IPFW_IS_PIPE; if (V_fw_one_pass) args->rule.info |= IPFW_ONEPASS; retval = IP_FW_DUMMYNET; l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ break; case O_DIVERT: case O_TEE: if (args->eh) /* not on layer 2 */ break; /* otherwise this is terminal */ l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ retval = (cmd->opcode == O_DIVERT) ? IP_FW_DIVERT : IP_FW_TEE; set_match(args, f_pos, chain); args->rule.info = (cmd->arg1 == IP_FW_TABLEARG) ? tablearg : cmd->arg1; break; case O_COUNT: f->pcnt++; /* update stats */ f->bcnt += pktlen; f->timestamp = time_uptime; l = 0; /* exit inner loop */ break; case O_SKIPTO: f->pcnt++; /* update stats */ f->bcnt += pktlen; f->timestamp = time_uptime; /* If possible use cached f_pos (in f->next_rule), * whose version is written in f->next_rule * (horrible hacks to avoid changing the ABI). */ if (cmd->arg1 != IP_FW_TABLEARG && (uintptr_t)f->x_next == chain->id) { f_pos = (uintptr_t)f->next_rule; } else { int i = (cmd->arg1 == IP_FW_TABLEARG) ? tablearg : cmd->arg1; /* make sure we do not jump backward */ if (i <= f->rulenum) i = f->rulenum + 1; f_pos = ipfw_find_rule(chain, i, 0); /* update the cache */ if (cmd->arg1 != IP_FW_TABLEARG) { f->next_rule = (void *)(uintptr_t)f_pos; f->x_next = (void *)(uintptr_t)chain->id; } } /* * Skip disabled rules, and re-enter * the inner loop with the correct * f_pos, f, l and cmd. * Also clear cmdlen and skip_or */ for (; f_pos < chain->n_rules - 1 && (V_set_disable & (1 << chain->map[f_pos]->set)); f_pos++) ; /* Re-enter the inner loop at the skipto rule. */ f = chain->map[f_pos]; l = f->cmd_len; cmd = f->cmd; match = 1; cmdlen = 0; skip_or = 0; continue; break; /* not reached */ case O_CALLRETURN: { /* * Implementation of `subroutine' call/return, * in the stack carried in an mbuf tag. This * is different from `skipto' in that any call * address is possible (`skipto' must prevent * backward jumps to avoid endless loops). * We have `return' action when F_NOT flag is * present. The `m_tag_id' field is used as * stack pointer. */ struct m_tag *mtag; uint16_t jmpto, *stack; #define IS_CALL ((cmd->len & F_NOT) == 0) #define IS_RETURN ((cmd->len & F_NOT) != 0) /* * Hand-rolled version of m_tag_locate() with * wildcard `type'. * If not already tagged, allocate new tag. */ mtag = m_tag_first(m); while (mtag != NULL) { if (mtag->m_tag_cookie == MTAG_IPFW_CALL) break; mtag = m_tag_next(m, mtag); } if (mtag == NULL && IS_CALL) { mtag = m_tag_alloc(MTAG_IPFW_CALL, 0, IPFW_CALLSTACK_SIZE * sizeof(uint16_t), M_NOWAIT); if (mtag != NULL) m_tag_prepend(m, mtag); } /* * On error both `call' and `return' just * continue with next rule. */ if (IS_RETURN && (mtag == NULL || mtag->m_tag_id == 0)) { l = 0; /* exit inner loop */ break; } if (IS_CALL && (mtag == NULL || mtag->m_tag_id >= IPFW_CALLSTACK_SIZE)) { printf("ipfw: call stack error, " "go to next rule\n"); l = 0; /* exit inner loop */ break; } f->pcnt++; /* update stats */ f->bcnt += pktlen; f->timestamp = time_uptime; stack = (uint16_t *)(mtag + 1); /* * The `call' action may use cached f_pos * (in f->next_rule), whose version is written * in f->next_rule. * The `return' action, however, doesn't have * fixed jump address in cmd->arg1 and can't use * cache. */ if (IS_CALL) { stack[mtag->m_tag_id] = f->rulenum; mtag->m_tag_id++; if (cmd->arg1 != IP_FW_TABLEARG && (uintptr_t)f->x_next == chain->id) { f_pos = (uintptr_t)f->next_rule; } else { jmpto = (cmd->arg1 == IP_FW_TABLEARG) ? tablearg: cmd->arg1; f_pos = ipfw_find_rule(chain, jmpto, 0); /* update the cache */ if (cmd->arg1 != IP_FW_TABLEARG) { f->next_rule = (void *)(uintptr_t) f_pos; f->x_next = (void *)(uintptr_t) chain->id; } } } else { /* `return' action */ mtag->m_tag_id--; jmpto = stack[mtag->m_tag_id] + 1; f_pos = ipfw_find_rule(chain, jmpto, 0); } /* * Skip disabled rules, and re-enter * the inner loop with the correct * f_pos, f, l and cmd. * Also clear cmdlen and skip_or */ for (; f_pos < chain->n_rules - 1 && (V_set_disable & (1 << chain->map[f_pos]->set)); f_pos++) ; /* Re-enter the inner loop at the dest rule. */ f = chain->map[f_pos]; l = f->cmd_len; cmd = f->cmd; cmdlen = 0; skip_or = 0; continue; break; /* NOTREACHED */ } #undef IS_CALL #undef IS_RETURN case O_REJECT: /* * Drop the packet and send a reject notice * if the packet is not ICMP (or is an ICMP * query), and it is not multicast/broadcast. */ if (hlen > 0 && is_ipv4 && offset == 0 && (proto != IPPROTO_ICMP || is_icmp_query(ICMP(ulp))) && !(m->m_flags & (M_BCAST|M_MCAST)) && !IN_MULTICAST(ntohl(dst_ip.s_addr))) { send_reject(args, cmd->arg1, iplen, ip); m = args->m; } /* FALLTHROUGH */ #ifdef INET6 case O_UNREACH6: if (hlen > 0 && is_ipv6 && ((offset & IP6F_OFF_MASK) == 0) && (proto != IPPROTO_ICMPV6 || (is_icmp6_query(icmp6_type) == 1)) && !(m->m_flags & (M_BCAST|M_MCAST)) && !IN6_IS_ADDR_MULTICAST(&args->f_id.dst_ip6)) { send_reject6( args, cmd->arg1, hlen, (struct ip6_hdr *)ip); m = args->m; } /* FALLTHROUGH */ #endif case O_DENY: retval = IP_FW_DENY; l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ break; case O_FORWARD_IP: if (args->eh) /* not valid on layer2 pkts */ break; if (q == NULL || q->rule != f || dyn_dir == MATCH_FORWARD) { struct sockaddr_in *sa; sa = &(((ipfw_insn_sa *)cmd)->sa); 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; l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ break; #ifdef INET6 case O_FORWARD_IP6: if (args->eh) /* not valid on layer2 pkts */ break; if (q == NULL || q->rule != f || dyn_dir == MATCH_FORWARD) { struct sockaddr_in6 *sin6; sin6 = &(((ipfw_insn_sa6 *)cmd)->sa); args->next_hop6 = sin6; } retval = IP_FW_PASS; l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ break; #endif case O_NETGRAPH: case O_NGTEE: set_match(args, f_pos, chain); args->rule.info = (cmd->arg1 == IP_FW_TABLEARG) ? tablearg : cmd->arg1; if (V_fw_one_pass) args->rule.info |= IPFW_ONEPASS; retval = (cmd->opcode == O_NETGRAPH) ? IP_FW_NETGRAPH : IP_FW_NGTEE; l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ break; case O_SETFIB: { uint32_t fib; f->pcnt++; /* update stats */ f->bcnt += pktlen; f->timestamp = time_uptime; fib = (cmd->arg1 == IP_FW_TABLEARG) ? tablearg: cmd->arg1; if (fib >= rt_numfibs) fib = 0; M_SETFIB(m, fib); args->f_id.fib = fib; l = 0; /* exit inner loop */ break; } case O_NAT: if (!IPFW_NAT_LOADED) { retval = IP_FW_DENY; } else { struct cfg_nat *t; int nat_id; set_match(args, f_pos, chain); /* Check if this is 'global' nat rule */ if (cmd->arg1 == 0) { retval = ipfw_nat_ptr(args, NULL, m); l = 0; done = 1; break; } t = ((ipfw_insn_nat *)cmd)->nat; if (t == NULL) { nat_id = (cmd->arg1 == IP_FW_TABLEARG) ? tablearg : cmd->arg1; t = (*lookup_nat_ptr)(&chain->nat, nat_id); if (t == NULL) { retval = IP_FW_DENY; l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ break; } if (cmd->arg1 != IP_FW_TABLEARG) ((ipfw_insn_nat *)cmd)->nat = t; } retval = ipfw_nat_ptr(args, t, m); } l = 0; /* exit inner loop */ done = 1; /* exit outer loop */ break; case O_REASS: { int ip_off; f->pcnt++; f->bcnt += pktlen; l = 0; /* in any case exit inner loop */ ip_off = ntohs(ip->ip_off); /* if not fragmented, go to next rule */ if ((ip_off & (IP_MF | IP_OFFMASK)) == 0) break; /* * ip_reass() expects len & off in host * byte order. */ SET_HOST_IPLEN(ip); args->m = m = ip_reass(m); /* * do IP header checksum fixup. */ if (m == NULL) { /* fragment got swallowed */ retval = IP_FW_DENY; } else { /* good, packet complete */ int hlen; ip = mtod(m, struct ip *); hlen = ip->ip_hl << 2; SET_NET_IPLEN(ip); ip->ip_sum = 0; if (hlen == sizeof(struct ip)) ip->ip_sum = in_cksum_hdr(ip); else ip->ip_sum = in_cksum(m, hlen); retval = IP_FW_REASS; set_match(args, f_pos, chain); } done = 1; /* exit outer loop */ break; } default: panic("-- unknown opcode %d\n", cmd->opcode); } /* end of switch() on opcodes */ /* * if we get here with l=0, then match is irrelevant. */ if (cmd->len & F_NOT) match = !match; if (match) { if (cmd->len & F_OR) skip_or = 1; } else { if (!(cmd->len & F_OR)) /* not an OR block, */ break; /* try next rule */ } } /* end of inner loop, scan opcodes */ #undef PULLUP_LEN if (done) break; /* next_rule:; */ /* try next rule */ } /* end of outer for, scan rules */ if (done) { struct ip_fw *rule = chain->map[f_pos]; /* Update statistics */ rule->pcnt++; rule->bcnt += pktlen; rule->timestamp = time_uptime; } else { retval = IP_FW_DENY; printf("ipfw: ouch!, skip past end of rules, denying packet\n"); } IPFW_RUNLOCK(chain); #ifdef __FreeBSD__ if (ucred_cache != NULL) crfree(ucred_cache); #endif return (retval); pullup_failed: if (V_fw_verbose) printf("ipfw: pullup failed\n"); return (IP_FW_DENY); } /* * Module and VNET glue */ /* * Stuff that must be initialised only on boot or module load */ static int ipfw_init(void) { int error = 0; ipfw_dyn_attach(); /* * Only print out this stuff the first time around, * when called from the sysinit code. */ printf("ipfw2 " #ifdef INET6 "(+ipv6) " #endif "initialized, divert %s, nat %s, " "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_to_accept ? "accept" : "deny"); /* * Note: V_xxx variables can be accessed here but the vnet specific * initializer may not have been called yet for the VIMAGE case. * Tuneables will have been processed. We will print out values for * the default vnet. * XXX This should all be rationalized AFTER 8.0 */ if (V_fw_verbose == 0) printf("disabled\n"); else if (V_verbose_limit == 0) printf("unlimited\n"); else printf("limited to %d packets/entry by default\n", V_verbose_limit); ipfw_log_bpf(1); /* init */ return (error); } /* * Called for the removal of the last instance only on module unload. */ static void ipfw_destroy(void) { ipfw_log_bpf(0); /* uninit */ ipfw_dyn_detach(); printf("IP firewall unloaded\n"); } /* * Stuff that must be initialized for every instance * (including the first of course). */ static int vnet_ipfw_init(const void *unused) { int error; struct ip_fw *rule = NULL; struct ip_fw_chain *chain; chain = &V_layer3_chain; /* First set up some values that are compile time options */ V_autoinc_step = 100; /* bounded to 1..1000 in add_rule() */ V_fw_deny_unknown_exthdrs = 1; #ifdef IPFIREWALL_VERBOSE V_fw_verbose = 1; #endif #ifdef IPFIREWALL_VERBOSE_LIMIT V_verbose_limit = IPFIREWALL_VERBOSE_LIMIT; #endif #ifdef IPFIREWALL_NAT LIST_INIT(&chain->nat); #endif /* insert the default rule and create the initial map */ chain->n_rules = 1; chain->static_len = sizeof(struct ip_fw); chain->map = malloc(sizeof(struct ip_fw *), M_IPFW, M_NOWAIT | M_ZERO); if (chain->map) rule = malloc(chain->static_len, M_IPFW, M_NOWAIT | M_ZERO); if (rule == NULL) { if (chain->map) free(chain->map, M_IPFW); printf("ipfw2: ENOSPC initializing default rule " "(support disabled)\n"); return (ENOSPC); } error = ipfw_init_tables(chain); if (error) { panic("init_tables"); /* XXX Marko fix this ! */ } /* fill and insert the default rule */ rule->act_ofs = 0; rule->rulenum = IPFW_DEFAULT_RULE; rule->cmd_len = 1; rule->set = RESVD_SET; rule->cmd[0].len = 1; rule->cmd[0].opcode = default_to_accept ? O_ACCEPT : O_DENY; chain->rules = chain->default_rule = chain->map[0] = rule; chain->id = rule->id = 1; IPFW_LOCK_INIT(chain); ipfw_dyn_init(); /* First set up some values that are compile time options */ V_ipfw_vnet_ready = 1; /* Open for business */ /* * Hook the sockopt handler, and the layer2 (V_ip_fw_chk_ptr) * and pfil hooks for ipv4 and ipv6. Even if the latter two fail * we still keep the module alive because the sockopt and * layer2 paths are still useful. * ipfw[6]_hook return 0 on success, ENOENT on failure, * so we can ignore the exact return value and just set a flag. * * Note that V_fw[6]_enable are manipulated by a SYSCTL_PROC so * changes in the underlying (per-vnet) variables trigger * immediate hook()/unhook() calls. * In layer2 we have the same behaviour, except that V_ether_ipfw * is checked on each packet because there are no pfil hooks. */ V_ip_fw_ctl_ptr = ipfw_ctl; V_ip_fw_chk_ptr = ipfw_chk; error = ipfw_attach_hooks(1); return (error); } /* * Called for the removal of each instance. */ static int vnet_ipfw_uninit(const void *unused) { struct ip_fw *reap, *rule; struct ip_fw_chain *chain = &V_layer3_chain; int i; V_ipfw_vnet_ready = 0; /* tell new callers to go away */ /* * disconnect from ipv4, ipv6, layer2 and sockopt. * Then grab, release and grab again the WLOCK so we make * sure the update is propagated and nobody will be in. */ (void)ipfw_attach_hooks(0 /* detach */); V_ip_fw_chk_ptr = NULL; V_ip_fw_ctl_ptr = NULL; IPFW_UH_WLOCK(chain); IPFW_UH_WUNLOCK(chain); IPFW_UH_WLOCK(chain); IPFW_WLOCK(chain); IPFW_WUNLOCK(chain); IPFW_WLOCK(chain); ipfw_dyn_uninit(0); /* run the callout_drain */ ipfw_destroy_tables(chain); reap = NULL; for (i = 0; i < chain->n_rules; i++) { rule = chain->map[i]; rule->x_next = reap; reap = rule; } if (chain->map) free(chain->map, M_IPFW); IPFW_WUNLOCK(chain); IPFW_UH_WUNLOCK(chain); if (reap != NULL) ipfw_reap_rules(reap); IPFW_LOCK_DESTROY(chain); ipfw_dyn_uninit(1); /* free the remaining parts */ return 0; } /* * Module event handler. * In general we have the choice of handling most of these events by the * event handler or by the (VNET_)SYS(UN)INIT handlers. I have chosen to * use the SYSINIT handlers as they are more capable of expressing the * flow of control during module and vnet operations, so this is just * a skeleton. Note there is no SYSINIT equivalent of the module * SHUTDOWN handler, but we don't have anything to do in that case anyhow. */ static int ipfw_modevent(module_t mod, int type, void *unused) { int err = 0; switch (type) { case MOD_LOAD: /* Called once at module load or * system boot if compiled in. */ break; case MOD_QUIESCE: /* Called before unload. May veto unloading. */ break; case MOD_UNLOAD: /* Called during unload. */ break; case MOD_SHUTDOWN: /* Called during system shutdown. */ break; default: err = EOPNOTSUPP; break; } return err; } static moduledata_t ipfwmod = { "ipfw", ipfw_modevent, 0 }; /* Define startup order. */ #define IPFW_SI_SUB_FIREWALL SI_SUB_PROTO_IFATTACHDOMAIN #define IPFW_MODEVENT_ORDER (SI_ORDER_ANY - 255) /* On boot slot in here. */ #define IPFW_MODULE_ORDER (IPFW_MODEVENT_ORDER + 1) /* A little later. */ #define IPFW_VNET_ORDER (IPFW_MODEVENT_ORDER + 2) /* Later still. */ DECLARE_MODULE(ipfw, ipfwmod, IPFW_SI_SUB_FIREWALL, IPFW_MODEVENT_ORDER); MODULE_VERSION(ipfw, 2); /* should declare some dependencies here */ /* * Starting up. Done in order after ipfwmod() has been called. * VNET_SYSINIT is also called for each existing vnet and each new vnet. */ SYSINIT(ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER, ipfw_init, NULL); VNET_SYSINIT(vnet_ipfw_init, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER, vnet_ipfw_init, NULL); /* * Closing up shop. These are done in REVERSE ORDER, but still * after ipfwmod() has been called. Not called on reboot. * VNET_SYSUNINIT is also called for each exiting vnet as it exits. * or when the module is unloaded. */ SYSUNINIT(ipfw_destroy, IPFW_SI_SUB_FIREWALL, IPFW_MODULE_ORDER, ipfw_destroy, NULL); VNET_SYSUNINIT(vnet_ipfw_uninit, IPFW_SI_SUB_FIREWALL, IPFW_VNET_ORDER, vnet_ipfw_uninit, NULL); /* end of file */ diff --git a/sys/netinet/ipfw/ip_fw_dynamic.c b/sys/netinet/ipfw/ip_fw_dynamic.c index 0bc4cc112ce2..d1eec89eed4f 100644 --- a/sys/netinet/ipfw/ip_fw_dynamic.c +++ b/sys/netinet/ipfw/ip_fw_dynamic.c @@ -1,1241 +1,1241 @@ /*- * 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 __FBSDID("$FreeBSD$"); #define DEB(x) #define DDB(x) x /* * Dynamic rule support for ipfw */ -#if !defined(KLD_MODULE) #include "opt_ipfw.h" +#if !defined(KLD_MODULE) #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 #include #include #include #include #include #include #include #include #include /* for ETHERTYPE_IP */ #include #include #include #include #include /* ip_defttl */ #include #include #include #include #include /* IN6_ARE_ADDR_EQUAL */ #ifdef INET6 #include #include #endif #include /* XXX for in_cksum */ #ifdef MAC #include #endif /* * 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 variables followed by global ones */ static VNET_DEFINE(ipfw_dyn_rule **, ipfw_dyn_v); static VNET_DEFINE(u_int32_t, dyn_buckets); static VNET_DEFINE(u_int32_t, curr_dyn_buckets); static VNET_DEFINE(struct callout, ipfw_timeout); #define V_ipfw_dyn_v VNET(ipfw_dyn_v) #define V_dyn_buckets VNET(dyn_buckets) #define V_curr_dyn_buckets VNET(curr_dyn_buckets) #define V_ipfw_timeout VNET(ipfw_timeout) static uma_zone_t ipfw_dyn_rule_zone; #ifndef __FreeBSD__ DEFINE_SPINLOCK(ipfw_dyn_mtx); #else static struct mtx ipfw_dyn_mtx; /* mutex guarding dynamic rules */ #endif #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) void ipfw_dyn_unlock(void) { IPFW_DYN_UNLOCK(); } /* * Timeouts for various events in handing dynamic rules. */ static VNET_DEFINE(u_int32_t, dyn_ack_lifetime); static VNET_DEFINE(u_int32_t, dyn_syn_lifetime); static VNET_DEFINE(u_int32_t, dyn_fin_lifetime); static VNET_DEFINE(u_int32_t, dyn_rst_lifetime); static VNET_DEFINE(u_int32_t, dyn_udp_lifetime); static VNET_DEFINE(u_int32_t, dyn_short_lifetime); #define V_dyn_ack_lifetime VNET(dyn_ack_lifetime) #define V_dyn_syn_lifetime VNET(dyn_syn_lifetime) #define V_dyn_fin_lifetime VNET(dyn_fin_lifetime) #define V_dyn_rst_lifetime VNET(dyn_rst_lifetime) #define V_dyn_udp_lifetime VNET(dyn_udp_lifetime) #define V_dyn_short_lifetime VNET(dyn_short_lifetime) /* * 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 VNET_DEFINE(u_int32_t, dyn_keepalive_interval); static VNET_DEFINE(u_int32_t, dyn_keepalive_period); static VNET_DEFINE(u_int32_t, dyn_keepalive); #define V_dyn_keepalive_interval VNET(dyn_keepalive_interval) #define V_dyn_keepalive_period VNET(dyn_keepalive_period) #define V_dyn_keepalive VNET(dyn_keepalive) static VNET_DEFINE(u_int32_t, dyn_count); /* # of dynamic rules */ static VNET_DEFINE(u_int32_t, dyn_max); /* max # of dynamic rules */ #define V_dyn_count VNET(dyn_count) #define V_dyn_max VNET(dyn_max) #ifdef SYSCTL_NODE SYSBEGIN(f2) SYSCTL_DECL(_net_inet_ip_fw); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_buckets, CTLFLAG_RW, &VNET_NAME(dyn_buckets), 0, "Number of dyn. buckets"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, curr_dyn_buckets, CTLFLAG_RD, &VNET_NAME(curr_dyn_buckets), 0, "Current Number of dyn. buckets"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_count, CTLFLAG_RD, &VNET_NAME(dyn_count), 0, "Number of dyn. rules"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_max, CTLFLAG_RW, &VNET_NAME(dyn_max), 0, "Max number of dyn. rules"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_ack_lifetime, CTLFLAG_RW, &VNET_NAME(dyn_ack_lifetime), 0, "Lifetime of dyn. rules for acks"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_syn_lifetime, CTLFLAG_RW, &VNET_NAME(dyn_syn_lifetime), 0, "Lifetime of dyn. rules for syn"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_fin_lifetime, CTLFLAG_RW, &VNET_NAME(dyn_fin_lifetime), 0, "Lifetime of dyn. rules for fin"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_rst_lifetime, CTLFLAG_RW, &VNET_NAME(dyn_rst_lifetime), 0, "Lifetime of dyn. rules for rst"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_udp_lifetime, CTLFLAG_RW, &VNET_NAME(dyn_udp_lifetime), 0, "Lifetime of dyn. rules for UDP"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_short_lifetime, CTLFLAG_RW, &VNET_NAME(dyn_short_lifetime), 0, "Lifetime of dyn. rules for other situations"); SYSCTL_VNET_UINT(_net_inet_ip_fw, OID_AUTO, dyn_keepalive, CTLFLAG_RW, &VNET_NAME(dyn_keepalive), 0, "Enable keepalives for dyn. rules"); SYSEND #endif /* SYSCTL_NODE */ 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; } /* * 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 &= (V_curr_dyn_buckets - 1); return i; } static __inline void unlink_dyn_rule_print(struct ipfw_flow_id *id) { struct in_addr da; #ifdef INET6 char src[INET6_ADDRSTRLEN], dst[INET6_ADDRSTRLEN]; #else char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN]; #endif #ifdef INET6 if (IS_IP6_FLOW_ID(id)) { ip6_sprintf(src, &id->src_ip6); ip6_sprintf(dst, &id->dst_ip6); } else #endif { da.s_addr = htonl(id->src_ip); inet_ntoa_r(da, src); da.s_addr = htonl(id->dst_ip); inet_ntoa_r(da, dst); } printf("ipfw: unlink entry %s %d -> %s %d, %d left\n", src, id->src_port, dst, id->dst_port, V_dyn_count - 1); } /** * 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(unlink_dyn_rule_print(&q->id);) \ if (prev != NULL) \ prev->next = q = q->next; \ else \ head = q = q->next; \ V_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 (V_ipfw_dyn_v == NULL || V_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 < V_curr_dyn_buckets ; i++) { for (prev=NULL, q = V_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, V_ipfw_dyn_v[i], q); continue; } next: prev=q; q=q->next; } } if (pass++ < max_pass) goto next_pass; } void ipfw_remove_dyn_children(struct ip_fw *rule) { IPFW_DYN_LOCK(); remove_dyn_rule(rule, NULL /* force removal */); IPFW_DYN_UNLOCK(); } /** * lookup a dynamic rule, locked version */ 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 (V_ipfw_dyn_v == NULL) goto done; /* not found */ i = hash_packet( pkt ); for (prev=NULL, q = V_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, V_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 = V_ipfw_dyn_v[i]; V_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 + V_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 + V_dyn_ack_lifetime; break; case BOTH_SYN | BOTH_FIN: /* both sides closed */ if (V_dyn_fin_lifetime >= V_dyn_keepalive_period) V_dyn_fin_lifetime = V_dyn_keepalive_period - 1; q->expire = time_uptime + V_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 (V_dyn_rst_lifetime >= V_dyn_keepalive_period) V_dyn_rst_lifetime = V_dyn_keepalive_period - 1; q->expire = time_uptime + V_dyn_rst_lifetime; break; } } else if (pkt->proto == IPPROTO_UDP) { q->expire = time_uptime + V_dyn_udp_lifetime; } else { /* other protocols */ q->expire = time_uptime + V_dyn_short_lifetime; } done: if (match_direction) *match_direction = dir; return q; } ipfw_dyn_rule * ipfw_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 (V_dyn_buckets > 65536) V_dyn_buckets = 1024; if ((V_dyn_buckets & (V_dyn_buckets-1)) != 0) { /* not a power of 2 */ V_dyn_buckets = V_curr_dyn_buckets; /* reset */ return; } V_curr_dyn_buckets = V_dyn_buckets; if (V_ipfw_dyn_v != NULL) free(V_ipfw_dyn_v, M_IPFW); for (;;) { V_ipfw_dyn_v = malloc(V_curr_dyn_buckets * sizeof(ipfw_dyn_rule *), M_IPFW, M_NOWAIT | M_ZERO); if (V_ipfw_dyn_v != NULL || V_curr_dyn_buckets <= 2) break; V_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 (V_ipfw_dyn_v == NULL || (V_dyn_count == 0 && V_dyn_buckets != V_curr_dyn_buckets)) { realloc_dynamic_table(); if (V_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 + V_dyn_syn_lifetime; r->rule = rule; r->dyn_type = dyn_type; r->pcnt = r->bcnt = 0; r->count = 0; r->bucket = i; r->next = V_ipfw_dyn_v[i]; V_ipfw_dyn_v[i] = r; V_dyn_count++; DEB({ struct in_addr da; #ifdef INET6 char src[INET6_ADDRSTRLEN]; char dst[INET6_ADDRSTRLEN]; #else char src[INET_ADDRSTRLEN]; char dst[INET_ADDRSTRLEN]; #endif #ifdef INET6 if (IS_IP6_FLOW_ID(&(r->id))) { ip6_sprintf(src, &r->id.src_ip6); ip6_sprintf(dst, &r->id.dst_ip6); } else #endif { da.s_addr = htonl(r->id.src_ip); inet_ntoa_r(da, src); da.s_addr = htonl(r->id.dst_ip); inet_ntoa_r(da, dst); } printf("ipfw: add dyn entry ty %d %s %d -> %s %d, total %d\n", dyn_type, src, r->id.src_port, dst, r->id.dst_port, V_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 (V_ipfw_dyn_v) { int is_v6 = IS_IP6_FLOW_ID(pkt); i = hash_packet( pkt ); for (q = V_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 + V_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. */ int ipfw_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; #ifdef INET6 char src[INET6_ADDRSTRLEN + 2], dst[INET6_ADDRSTRLEN + 2]; #else char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN]; #endif src[0] = '\0'; dst[0] = '\0'; IPFW_DYN_LOCK(); DEB( #ifdef INET6 if (IS_IP6_FLOW_ID(&(args->f_id))) { ip6_sprintf(src, &args->f_id.src_ip6); ip6_sprintf(dst, &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); } printf("ipfw: %s: type %d %s %u -> %s %u\n", __func__, cmd->o.opcode, src, args->f_id.src_port, dst, args->f_id.dst_port); src[0] = '\0'; dst[0] = '\0'; ) q = lookup_dyn_rule_locked(&args->f_id, NULL, NULL); if (q != NULL) { /* should never occur */ DEB( if (last_log != time_uptime) { last_log = time_uptime; printf("ipfw: %s: entry already present, done\n", __func__); }) IPFW_DYN_UNLOCK(); return (0); } if (V_dyn_count >= V_dyn_max) /* Run out of slots, try to remove any expired rule. */ remove_dyn_rule(NULL, (ipfw_dyn_rule *)1); if (V_dyn_count >= V_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 (V_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. */ struct mbuf * ipfw_send_pkt(struct mbuf *replyto, struct ipfw_flow_id *id, u_int32_t seq, u_int32_t ack, int flags) { struct mbuf *m = NULL; /* stupid compiler */ int len, dir; struct ip *h = NULL; /* stupid compiler */ #ifdef INET6 struct ip6_hdr *h6 = NULL; #endif struct tcphdr *th = NULL; MGETHDR(m, M_DONTWAIT, MT_DATA); if (m == NULL) return (NULL); M_SETFIB(m, id->fib); #ifdef MAC if (replyto != NULL) mac_netinet_firewall_reply(replyto, m); else mac_netinet_firewall_send(m); #else (void)replyto; /* don't warn about unused arg */ #endif switch (id->addr_type) { case 4: len = sizeof(struct ip) + sizeof(struct tcphdr); break; #ifdef INET6 case 6: len = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); break; #endif default: /* XXX: log me?!? */ FREE_PKT(m); return (NULL); } dir = ((flags & (TH_SYN | TH_RST)) == TH_SYN); m->m_data += max_linkhdr; m->m_flags |= M_SKIP_FIREWALL; m->m_pkthdr.len = m->m_len = len; m->m_pkthdr.rcvif = NULL; bzero(m->m_data, len); switch (id->addr_type) { case 4: h = mtod(m, struct ip *); /* prepare for checksum */ h->ip_p = IPPROTO_TCP; h->ip_len = htons(sizeof(struct tcphdr)); if (dir) { h->ip_src.s_addr = htonl(id->src_ip); h->ip_dst.s_addr = htonl(id->dst_ip); } else { h->ip_src.s_addr = htonl(id->dst_ip); h->ip_dst.s_addr = htonl(id->src_ip); } th = (struct tcphdr *)(h + 1); break; #ifdef INET6 case 6: h6 = mtod(m, struct ip6_hdr *); /* prepare for checksum */ h6->ip6_nxt = IPPROTO_TCP; h6->ip6_plen = htons(sizeof(struct tcphdr)); if (dir) { h6->ip6_src = id->src_ip6; h6->ip6_dst = id->dst_ip6; } else { h6->ip6_src = id->dst_ip6; h6->ip6_dst = id->src_ip6; } th = (struct tcphdr *)(h6 + 1); break; #endif } if (dir) { th->th_sport = htons(id->src_port); th->th_dport = htons(id->dst_port); } else { th->th_sport = htons(id->dst_port); th->th_dport = htons(id->src_port); } th->th_off = sizeof(struct tcphdr) >> 2; if (flags & TH_RST) { if (flags & TH_ACK) { th->th_seq = htonl(ack); th->th_flags = TH_RST; } else { if (flags & TH_SYN) seq++; th->th_ack = htonl(seq); th->th_flags = TH_RST | TH_ACK; } } else { /* * Keepalive - use caller provided sequence numbers */ th->th_seq = htonl(seq); th->th_ack = htonl(ack); th->th_flags = TH_ACK; } switch (id->addr_type) { case 4: th->th_sum = in_cksum(m, len); /* finish the ip header */ h->ip_v = 4; h->ip_hl = sizeof(*h) >> 2; h->ip_tos = IPTOS_LOWDELAY; h->ip_off = 0; /* ip_len must be in host format for ip_output */ h->ip_len = len; h->ip_ttl = V_ip_defttl; h->ip_sum = 0; break; #ifdef INET6 case 6: th->th_sum = in6_cksum(m, IPPROTO_TCP, sizeof(*h6), sizeof(struct tcphdr)); /* finish the ip6 header */ h6->ip6_vfc |= IPV6_VERSION; h6->ip6_hlim = IPV6_DEFHLIM; break; #endif } return (m); } /* * This procedure is only used to handle keepalives. It is invoked * every dyn_keepalive_period */ static void ipfw_tick(void * vnetx) { struct mbuf *m0, *m, *mnext, **mtailp; #ifdef INET6 struct mbuf *m6, **m6_tailp; #endif int i; ipfw_dyn_rule *q; #ifdef VIMAGE struct vnet *vp = vnetx; #endif CURVNET_SET(vp); if (V_dyn_keepalive == 0 || V_ipfw_dyn_v == NULL || V_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; #ifdef INET6 m6 = NULL; m6_tailp = &m6; #endif IPFW_DYN_LOCK(); for (i = 0 ; i < V_curr_dyn_buckets ; i++) { for (q = V_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 + V_dyn_keepalive_interval, q->expire)) continue; /* too early */ if (TIME_LEQ(q->expire, time_uptime)) continue; /* too late, rule expired */ m = ipfw_send_pkt(NULL, &(q->id), q->ack_rev - 1, q->ack_fwd, TH_SYN); mnext = ipfw_send_pkt(NULL, &(q->id), q->ack_fwd - 1, q->ack_rev, 0); switch (q->id.addr_type) { case 4: if (m != NULL) { *mtailp = m; mtailp = &(*mtailp)->m_nextpkt; } if (mnext != NULL) { *mtailp = mnext; mtailp = &(*mtailp)->m_nextpkt; } break; #ifdef INET6 case 6: if (m != NULL) { *m6_tailp = m; m6_tailp = &(*m6_tailp)->m_nextpkt; } if (mnext != NULL) { *m6_tailp = mnext; m6_tailp = &(*m6_tailp)->m_nextpkt; } break; #endif } m = mnext = NULL; } } 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); } #ifdef INET6 for (m = mnext = m6; m != NULL; m = mnext) { mnext = m->m_nextpkt; m->m_nextpkt = NULL; ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); } #endif done: callout_reset_on(&V_ipfw_timeout, V_dyn_keepalive_period * hz, ipfw_tick, vnetx, 0); CURVNET_RESTORE(); } void ipfw_dyn_attach(void) { 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(); } void ipfw_dyn_detach(void) { uma_zdestroy(ipfw_dyn_rule_zone); IPFW_DYN_LOCK_DESTROY(); } void ipfw_dyn_init(void) { V_ipfw_dyn_v = NULL; V_dyn_buckets = 256; /* must be power of 2 */ V_curr_dyn_buckets = 256; /* must be power of 2 */ V_dyn_ack_lifetime = 300; V_dyn_syn_lifetime = 20; V_dyn_fin_lifetime = 1; V_dyn_rst_lifetime = 1; V_dyn_udp_lifetime = 10; V_dyn_short_lifetime = 5; V_dyn_keepalive_interval = 20; V_dyn_keepalive_period = 5; V_dyn_keepalive = 1; /* do send keepalives */ V_dyn_max = 4096; /* max # of dynamic rules */ callout_init(&V_ipfw_timeout, CALLOUT_MPSAFE); callout_reset_on(&V_ipfw_timeout, hz, ipfw_tick, curvnet, 0); } void ipfw_dyn_uninit(int pass) { if (pass == 0) callout_drain(&V_ipfw_timeout); else { if (V_ipfw_dyn_v != NULL) free(V_ipfw_dyn_v, M_IPFW); } } int ipfw_dyn_len(void) { return (V_ipfw_dyn_v == NULL) ? 0 : (V_dyn_count * sizeof(ipfw_dyn_rule)); } void ipfw_get_dynamic(char **pbp, const char *ep) { ipfw_dyn_rule *p, *last = NULL; char *bp; int i; if (V_ipfw_dyn_v == NULL) return; bp = *pbp; IPFW_DYN_LOCK(); for (i = 0 ; i < V_curr_dyn_buckets; i++) for (p = V_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)); *pbp = bp; } /* end of file */ diff --git a/sys/netinet/ipfw/ip_fw_log.c b/sys/netinet/ipfw/ip_fw_log.c index 64548135c287..2f6e8b61fee8 100644 --- a/sys/netinet/ipfw/ip_fw_log.c +++ b/sys/netinet/ipfw/ip_fw_log.c @@ -1,474 +1,474 @@ /*- * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); /* * Logging support for ipfw */ -#if !defined(KLD_MODULE) #include "opt_ipfw.h" +#if !defined(KLD_MODULE) #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 #include #include #include #include #include #include #include /* for ETHERTYPE_IP */ #include #include #include /* for IFT_ETHER */ #include /* for BPF */ #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include /* ip6_sprintf() */ #endif #ifdef MAC #include #endif /* * 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)) #define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0 #define SNP(buf) buf, sizeof(buf) #ifdef WITHOUT_BPF void ipfw_log_bpf(int onoff) { } #else /* !WITHOUT_BPF */ static struct ifnet *log_if; /* hook to attach to bpf */ /* we use this dummy function for all ifnet callbacks */ static int log_dummy(struct ifnet *ifp, u_long cmd, caddr_t addr) { return EINVAL; } static int ipfw_log_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, struct route *ro) { if (m != NULL) m_freem(m); return EINVAL; } static void ipfw_log_start(struct ifnet* ifp) { panic("ipfw_log_start() must not be called"); } static const u_char ipfwbroadcastaddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; void ipfw_log_bpf(int onoff) { struct ifnet *ifp; if (onoff) { if (log_if) return; ifp = if_alloc(IFT_ETHER); if (ifp == NULL) return; if_initname(ifp, "ipfw", 0); ifp->if_mtu = 65536; ifp->if_flags = IFF_UP | IFF_SIMPLEX | IFF_MULTICAST; ifp->if_init = (void *)log_dummy; ifp->if_ioctl = log_dummy; ifp->if_start = ipfw_log_start; ifp->if_output = ipfw_log_output; ifp->if_addrlen = 6; ifp->if_hdrlen = 14; if_attach(ifp); ifp->if_broadcastaddr = ipfwbroadcastaddr; ifp->if_baudrate = IF_Mbps(10); bpfattach(ifp, DLT_EN10MB, 14); log_if = ifp; } else { if (log_if) { ether_ifdetach(log_if); if_free(log_if); } log_if = NULL; } } #endif /* !WITHOUT_BPF */ /* * We enter here when we have a rule with O_LOG. * XXX this function alone takes about 2Kbytes of code! */ 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) { char *action; int limit_reached = 0; char action2[92], proto[128], fragment[32]; if (V_fw_verbose == 0) { #ifndef WITHOUT_BPF if (log_if == NULL || log_if->if_bpf == NULL) return; if (args->eh) /* layer2, use orig hdr */ BPF_MTAP2(log_if, args->eh, ETHER_HDR_LEN, m); else /* Add fake header. Later we will store * more info in the header. */ BPF_MTAP2(log_if, "DDDDDDSSSSSS\x08\x00", ETHER_HDR_LEN, m); #endif /* !WITHOUT_BPF */ return; } /* the old 'log' function */ fragment[0] = '\0'; proto[0] = '\0'; if (f == NULL) { /* bogus pkt */ if (V_verbose_limit != 0 && V_norule_counter >= V_verbose_limit) return; V_norule_counter++; if (V_norule_counter == V_verbose_limit) limit_reached = V_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; #ifdef INET6 case O_FORWARD_IP6: { char buf[INET6_ADDRSTRLEN]; ipfw_insn_sa6 *sa = (ipfw_insn_sa6 *)cmd; int len; len = snprintf(SNPARGS(action2, 0), "Forward to [%s]", ip6_sprintf(buf, &sa->sa.sin6_addr)); if (sa->sa.sin6_port) snprintf(SNPARGS(action2, len), ":%u", sa->sa.sin6_port); } break; #endif 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; case O_REASS: action = "Reass"; break; case O_CALLRETURN: if (cmd->len & F_NOT) action = "Return"; else snprintf(SNPARGS(action2, 0), "Call %d", cmd->arg1); break; default: action = "UNKNOWN"; break; } } if (hlen == 0) { /* non-ip */ snprintf(SNPARGS(proto, 0), "MAC"); } else { int len; #ifdef INET6 char src[INET6_ADDRSTRLEN + 2], dst[INET6_ADDRSTRLEN + 2]; #else char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN]; #endif struct icmphdr *icmp; struct tcphdr *tcp; struct udphdr *udp; #ifdef INET6 struct ip6_hdr *ip6 = NULL; struct icmp6_hdr *icmp6; u_short ip6f_mf; #endif src[0] = '\0'; dst[0] = '\0'; #ifdef INET6 ip6f_mf = offset & IP6F_MORE_FRAG; offset &= IP6F_OFF_MASK; 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.extra, ntohs(ip6->ip6_plen) - hlen, ntohs(offset) << 3, ip6f_mf ? "+" : ""); } else #endif { int ipoff, iplen; ipoff = ntohs(ip->ip_off); iplen = ntohs(ip->ip_len); if (ipoff & (IP_MF | IP_OFFMASK)) snprintf(SNPARGS(fragment, 0), " (frag %d:%d@%d%s)", ntohs(ip->ip_id), iplen - (ip->ip_hl << 2), offset << 3, (ipoff & IP_MF) ? "+" : ""); } } #ifdef __FreeBSD__ 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 #endif 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); } /* end of file */ diff --git a/sys/netinet/ipfw/ip_fw_pfil.c b/sys/netinet/ipfw/ip_fw_pfil.c index 2aaa8457ea73..c470b1f2092d 100644 --- a/sys/netinet/ipfw/ip_fw_pfil.c +++ b/sys/netinet/ipfw/ip_fw_pfil.c @@ -1,463 +1,463 @@ /*- * Copyright (c) 2004 Andre Oppermann, Internet Business Solutions AG * All rights reserved. * * 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 __FBSDID("$FreeBSD$"); -#if !defined(KLD_MODULE) #include "opt_ipfw.h" +#if !defined(KLD_MODULE) #include "opt_ipdn.h" #include "opt_inet.h" #ifndef INET #error IPFIREWALL requires INET. #endif /* INET */ #endif /* KLD_MODULE */ #include "opt_inet6.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #include #endif #include #include #include static VNET_DEFINE(int, fw_enable) = 1; #define V_fw_enable VNET(fw_enable) #ifdef INET6 static VNET_DEFINE(int, fw6_enable) = 1; #define V_fw6_enable VNET(fw6_enable) #endif int ipfw_chg_hook(SYSCTL_HANDLER_ARGS); /* Forward declarations. */ static int ipfw_divert(struct mbuf **, int, struct ipfw_rule_ref *, int); #ifdef SYSCTL_NODE SYSBEGIN(f1) SYSCTL_DECL(_net_inet_ip_fw); SYSCTL_VNET_PROC(_net_inet_ip_fw, OID_AUTO, enable, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw_enable), 0, ipfw_chg_hook, "I", "Enable ipfw"); #ifdef INET6 SYSCTL_DECL(_net_inet6_ip6_fw); SYSCTL_VNET_PROC(_net_inet6_ip6_fw, OID_AUTO, enable, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE3, &VNET_NAME(fw6_enable), 0, ipfw_chg_hook, "I", "Enable ipfw+6"); #endif /* INET6 */ SYSEND #endif /* SYSCTL_NODE */ /* * The pfilter hook to pass packets to ipfw_chk and then to * dummynet, divert, netgraph or other modules. * The packet may be consumed. */ int ipfw_check_hook(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir, struct inpcb *inp) { struct ip_fw_args args; struct m_tag *tag; int ipfw; int ret; /* all the processing now uses ip_len in net format */ if (mtod(*m0, struct ip *)->ip_v == 4) SET_NET_IPLEN(mtod(*m0, struct ip *)); /* convert dir to IPFW values */ dir = (dir == PFIL_IN) ? DIR_IN : DIR_OUT; bzero(&args, sizeof(args)); again: /* * extract and remove the tag if present. If we are left * with onepass, optimize the outgoing path. */ tag = m_tag_locate(*m0, MTAG_IPFW_RULE, 0, NULL); if (tag != NULL) { args.rule = *((struct ipfw_rule_ref *)(tag+1)); m_tag_delete(*m0, tag); if (args.rule.info & IPFW_ONEPASS) { if (mtod(*m0, struct ip *)->ip_v == 4) SET_HOST_IPLEN(mtod(*m0, struct ip *)); return (0); } } args.m = *m0; args.oif = dir == DIR_OUT ? ifp : NULL; args.inp = inp; ipfw = ipfw_chk(&args); *m0 = args.m; KASSERT(*m0 != NULL || ipfw == IP_FW_DENY, ("%s: m0 is NULL", __func__)); /* breaking out of the switch means drop */ ret = 0; /* default return value for pass */ switch (ipfw) { case IP_FW_PASS: /* next_hop may be set by ipfw_chk */ if (args.next_hop == NULL && args.next_hop6 == NULL) break; /* pass */ #ifndef IPFIREWALL_FORWARD ret = EACCES; #else { struct m_tag *fwd_tag; size_t len; KASSERT(args.next_hop == NULL || args.next_hop6 == NULL, ("%s: both next_hop=%p and next_hop6=%p not NULL", __func__, args.next_hop, args.next_hop6)); #ifdef INET6 if (args.next_hop6 != NULL) len = sizeof(struct sockaddr_in6); #endif #ifdef INET if (args.next_hop != NULL) len = sizeof(struct sockaddr_in); #endif /* Incoming packets should not be tagged so we do not * m_tag_find. Outgoing packets may be tagged, so we * reuse the tag if present. */ fwd_tag = (dir == DIR_IN) ? NULL : m_tag_find(*m0, PACKET_TAG_IPFORWARD, NULL); if (fwd_tag != NULL) { m_tag_unlink(*m0, fwd_tag); } else { fwd_tag = m_tag_get(PACKET_TAG_IPFORWARD, len, M_NOWAIT); if (fwd_tag == NULL) { ret = EACCES; break; /* i.e. drop */ } } #ifdef INET6 if (args.next_hop6 != NULL) { bcopy(args.next_hop6, (fwd_tag+1), len); if (in6_localip(&args.next_hop6->sin6_addr)) (*m0)->m_flags |= M_FASTFWD_OURS; } #endif #ifdef INET if (args.next_hop != NULL) { bcopy(args.next_hop, (fwd_tag+1), len); if (in_localip(args.next_hop->sin_addr)) (*m0)->m_flags |= M_FASTFWD_OURS; } #endif m_tag_prepend(*m0, fwd_tag); } #endif break; case IP_FW_DENY: ret = EACCES; break; /* i.e. drop */ case IP_FW_DUMMYNET: ret = EACCES; if (ip_dn_io_ptr == NULL) break; /* i.e. drop */ if (mtod(*m0, struct ip *)->ip_v == 4) ret = ip_dn_io_ptr(m0, dir, &args); else if (mtod(*m0, struct ip *)->ip_v == 6) ret = ip_dn_io_ptr(m0, dir | PROTO_IPV6, &args); else break; /* drop it */ /* * XXX should read the return value. * dummynet normally eats the packet and sets *m0=NULL * unless the packet can be sent immediately. In this * case args is updated and we should re-run the * check without clearing args. */ if (*m0 != NULL) goto again; break; case IP_FW_TEE: case IP_FW_DIVERT: if (ip_divert_ptr == NULL) { ret = EACCES; break; /* i.e. drop */ } ret = ipfw_divert(m0, dir, &args.rule, (ipfw == IP_FW_TEE) ? 1 : 0); /* continue processing for the original packet (tee). */ if (*m0) goto again; break; case IP_FW_NGTEE: case IP_FW_NETGRAPH: if (ng_ipfw_input_p == NULL) { ret = EACCES; break; /* i.e. drop */ } ret = ng_ipfw_input_p(m0, dir, &args, (ipfw == IP_FW_NGTEE) ? 1 : 0); if (ipfw == IP_FW_NGTEE) /* ignore errors for NGTEE */ goto again; /* continue with packet */ break; case IP_FW_NAT: /* honor one-pass in case of successful nat */ if (V_fw_one_pass) break; /* ret is already 0 */ goto again; case IP_FW_REASS: goto again; /* continue with packet */ default: KASSERT(0, ("%s: unknown retval", __func__)); } if (ret != 0) { if (*m0) FREE_PKT(*m0); *m0 = NULL; } if (*m0 && mtod(*m0, struct ip *)->ip_v == 4) SET_HOST_IPLEN(mtod(*m0, struct ip *)); return ret; } /* do the divert, return 1 on error 0 on success */ static int ipfw_divert(struct mbuf **m0, int incoming, struct ipfw_rule_ref *rule, int tee) { /* * ipfw_chk() has already tagged the packet with the divert tag. * If tee is set, copy packet and return original. * If not tee, consume packet and send it to divert socket. */ struct mbuf *clone; struct ip *ip = mtod(*m0, struct ip *); struct m_tag *tag; /* Cloning needed for tee? */ if (tee == 0) { clone = *m0; /* use the original mbuf */ *m0 = NULL; } else { clone = m_dup(*m0, M_DONTWAIT); /* If we cannot duplicate the mbuf, we sacrifice the divert * chain and continue with the tee-ed packet. */ if (clone == NULL) return 1; } /* * Divert listeners can normally handle non-fragmented packets, * but we can only reass in the non-tee case. * This means that listeners on a tee rule may get fragments, * and have to live with that. * Note that we now have the 'reass' ipfw option so if we care * we can do it before a 'tee'. */ if (!tee) switch (ip->ip_v) { case IPVERSION: if (ntohs(ip->ip_off) & (IP_MF | IP_OFFMASK)) { int hlen; struct mbuf *reass; SET_HOST_IPLEN(ip); /* ip_reass wants host order */ reass = ip_reass(clone); /* Reassemble packet. */ if (reass == NULL) return 0; /* not an error */ /* if reass = NULL then it was consumed by ip_reass */ /* * IP header checksum fixup after reassembly and leave header * in network byte order. */ ip = mtod(reass, struct ip *); hlen = ip->ip_hl << 2; SET_NET_IPLEN(ip); ip->ip_sum = 0; if (hlen == sizeof(struct ip)) ip->ip_sum = in_cksum_hdr(ip); else ip->ip_sum = in_cksum(reass, hlen); clone = reass; } break; #ifdef INET6 case IPV6_VERSION >> 4: { struct ip6_hdr *const ip6 = mtod(clone, struct ip6_hdr *); if (ip6->ip6_nxt == IPPROTO_FRAGMENT) { int nxt, off; off = sizeof(struct ip6_hdr); nxt = frag6_input(&clone, &off, 0); if (nxt == IPPROTO_DONE) return (0); } break; } #endif } /* attach a tag to the packet with the reinject info */ tag = m_tag_alloc(MTAG_IPFW_RULE, 0, sizeof(struct ipfw_rule_ref), M_NOWAIT); if (tag == NULL) { FREE_PKT(clone); return 1; } *((struct ipfw_rule_ref *)(tag+1)) = *rule; m_tag_prepend(clone, tag); /* Do the dirty job... */ ip_divert_ptr(clone, incoming); return 0; } /* * attach or detach hooks for a given protocol family */ static int ipfw_hook(int onoff, int pf) { struct pfil_head *pfh; pfh = pfil_head_get(PFIL_TYPE_AF, pf); if (pfh == NULL) return ENOENT; (void) (onoff ? pfil_add_hook : pfil_remove_hook) (ipfw_check_hook, NULL, PFIL_IN | PFIL_OUT | PFIL_WAITOK, pfh); return 0; } int ipfw_attach_hooks(int arg) { int error = 0; if (arg == 0) /* detach */ ipfw_hook(0, AF_INET); else if (V_fw_enable && ipfw_hook(1, AF_INET) != 0) { error = ENOENT; /* see ip_fw_pfil.c::ipfw_hook() */ printf("ipfw_hook() error\n"); } #ifdef INET6 if (arg == 0) /* detach */ ipfw_hook(0, AF_INET6); else if (V_fw6_enable && ipfw_hook(1, AF_INET6) != 0) { error = ENOENT; printf("ipfw6_hook() error\n"); } #endif return error; } int ipfw_chg_hook(SYSCTL_HANDLER_ARGS) { int enable; int oldenable; int error; int af; if (arg1 == &VNET_NAME(fw_enable)) { enable = V_fw_enable; af = AF_INET; } #ifdef INET6 else if (arg1 == &VNET_NAME(fw6_enable)) { enable = V_fw6_enable; af = AF_INET6; } #endif else return (EINVAL); oldenable = enable; error = sysctl_handle_int(oidp, &enable, 0, req); if (error) return (error); enable = (enable) ? 1 : 0; if (enable == oldenable) return (0); error = ipfw_hook(enable, af); if (error) return (error); if (af == AF_INET) V_fw_enable = enable; #ifdef INET6 else if (af == AF_INET6) V_fw6_enable = enable; #endif return (0); } /* end of file */ diff --git a/sys/netinet/ipfw/ip_fw_sockopt.c b/sys/netinet/ipfw/ip_fw_sockopt.c index 375b9c506e4d..610570ba9a78 100644 --- a/sys/netinet/ipfw/ip_fw_sockopt.c +++ b/sys/netinet/ipfw/ip_fw_sockopt.c @@ -1,1358 +1,1358 @@ /*- * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa * * Supported by: Valeria Paoli * * 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 __FBSDID("$FreeBSD$"); /* * Sockopt support for ipfw. The routines here implement * the upper half of the ipfw code. */ -#if !defined(KLD_MODULE) #include "opt_ipfw.h" +#if !defined(KLD_MODULE) #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 #include #include #include /* struct m_tag used by nested headers */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* hooks */ #include #include #ifdef MAC #include #endif MALLOC_DEFINE(M_IPFW, "IpFw/IpAcct", "IpFw/IpAcct chain's"); /* * static variables followed by global ones (none in this file) */ /* * Find the smallest rule >= key, id. * We could use bsearch but it is so simple that we code it directly */ int ipfw_find_rule(struct ip_fw_chain *chain, uint32_t key, uint32_t id) { int i, lo, hi; struct ip_fw *r; for (lo = 0, hi = chain->n_rules - 1; lo < hi;) { i = (lo + hi) / 2; r = chain->map[i]; if (r->rulenum < key) lo = i + 1; /* continue from the next one */ else if (r->rulenum > key) hi = i; /* this might be good */ else if (r->id < id) lo = i + 1; /* continue from the next one */ else /* r->id >= id */ hi = i; /* this might be good */ }; return hi; } /* * allocate a new map, returns the chain locked. extra is the number * of entries to add or delete. */ static struct ip_fw ** get_map(struct ip_fw_chain *chain, int extra, int locked) { for (;;) { struct ip_fw **map; int i; i = chain->n_rules + extra; map = malloc(i * sizeof(struct ip_fw *), M_IPFW, locked ? M_NOWAIT : M_WAITOK); if (map == NULL) { printf("%s: cannot allocate map\n", __FUNCTION__); return NULL; } if (!locked) IPFW_UH_WLOCK(chain); if (i >= chain->n_rules + extra) /* good */ return map; /* otherwise we lost the race, free and retry */ if (!locked) IPFW_UH_WUNLOCK(chain); free(map, M_IPFW); } } /* * swap the maps. It is supposed to be called with IPFW_UH_WLOCK */ static struct ip_fw ** swap_map(struct ip_fw_chain *chain, struct ip_fw **new_map, int new_len) { struct ip_fw **old_map; IPFW_WLOCK(chain); chain->id++; chain->n_rules = new_len; old_map = chain->map; chain->map = new_map; IPFW_WUNLOCK(chain); return old_map; } /* * 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. * XXX DO NOT USE FOR THE DEFAULT RULE. * Must be called without IPFW_UH held */ int ipfw_add_rule(struct ip_fw_chain *chain, struct ip_fw *input_rule) { struct ip_fw *rule; int i, l, insert_before; struct ip_fw **map; /* the new array of pointers */ if (chain->rules == NULL || input_rule->rulenum > IPFW_DEFAULT_RULE-1) return (EINVAL); l = RULESIZE(input_rule); rule = malloc(l, M_IPFW, M_WAITOK | M_ZERO); if (rule == NULL) return (ENOSPC); /* get_map returns with IPFW_UH_WLOCK if successful */ map = get_map(chain, 1, 0 /* not locked */); if (map == NULL) { free(rule, M_IPFW); return ENOSPC; } bcopy(input_rule, rule, l); /* clear fields not settable from userland */ rule->x_next = NULL; rule->next_rule = NULL; rule->pcnt = 0; rule->bcnt = 0; rule->timestamp = 0; if (V_autoinc_step < 1) V_autoinc_step = 1; else if (V_autoinc_step > 1000) V_autoinc_step = 1000; /* find the insertion point, we will insert before */ insert_before = rule->rulenum ? rule->rulenum + 1 : IPFW_DEFAULT_RULE; i = ipfw_find_rule(chain, insert_before, 0); /* duplicate first part */ if (i > 0) bcopy(chain->map, map, i * sizeof(struct ip_fw *)); map[i] = rule; /* duplicate remaining part, we always have the default rule */ bcopy(chain->map + i, map + i + 1, sizeof(struct ip_fw *) *(chain->n_rules - i)); if (rule->rulenum == 0) { /* write back the number */ rule->rulenum = i > 0 ? map[i-1]->rulenum : 0; if (rule->rulenum < IPFW_DEFAULT_RULE - V_autoinc_step) rule->rulenum += V_autoinc_step; input_rule->rulenum = rule->rulenum; } rule->id = chain->id + 1; map = swap_map(chain, map, chain->n_rules + 1); chain->static_len += l; IPFW_UH_WUNLOCK(chain); if (map) free(map, M_IPFW); return (0); } /* * 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. */ void ipfw_reap_rules(struct ip_fw *head) { struct ip_fw *rule; while ((rule = head) != NULL) { head = head->x_next; free(rule, M_IPFW); } } /* * Used by del_entry() to check if a rule should be kept. * Returns 1 if the rule must be kept, 0 otherwise. * * Called with cmd = {0,1,5}. * cmd == 0 matches on rule numbers, excludes rules in RESVD_SET if n == 0 ; * cmd == 1 matches on set numbers only, rule numbers are ignored; * cmd == 5 matches on rule and set numbers. * * n == 0 is a wildcard for rule numbers, there is no wildcard for sets. * * Rules to keep are * (default || reserved || !match_set || !match_number) * where * default ::= (rule->rulenum == IPFW_DEFAULT_RULE) * // the default rule is always protected * * reserved ::= (cmd == 0 && n == 0 && rule->set == RESVD_SET) * // RESVD_SET is protected only if cmd == 0 and n == 0 ("ipfw flush") * * match_set ::= (cmd == 0 || rule->set == set) * // set number is ignored for cmd == 0 * * match_number ::= (cmd == 1 || n == 0 || n == rule->rulenum) * // number is ignored for cmd == 1 or n == 0 * */ static int keep_rule(struct ip_fw *rule, uint8_t cmd, uint8_t set, uint32_t n) { return (rule->rulenum == IPFW_DEFAULT_RULE) || (cmd == 0 && n == 0 && rule->set == RESVD_SET) || !(cmd == 0 || rule->set == set) || !(cmd == 1 || n == 0 || n == rule->rulenum); } /** * Remove all rules with given number, or do set manipulation. * Assumes chain != NULL && *chain != NULL. * * The argument is an uint32_t. The low 16 bit are the rule or set number; * the next 8 bits are the new set; the top 8 bits indicate the command: * * 0 delete rules numbered "rulenum" * 1 delete rules in set "rulenum" * 2 move rules "rulenum" to set "new_set" * 3 move rules from set "rulenum" to set "new_set" * 4 swap sets "rulenum" and "new_set" * 5 delete rules "rulenum" and set "new_set" */ static int del_entry(struct ip_fw_chain *chain, uint32_t arg) { struct ip_fw *rule; uint32_t num; /* rule number or old_set */ uint8_t cmd, new_set; int start, end, i, ofs, n; struct ip_fw **map = NULL; int error = 0; num = 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 (num >= IPFW_DEFAULT_RULE) return EINVAL; } else { if (num > RESVD_SET) /* old_set */ return EINVAL; } IPFW_UH_WLOCK(chain); /* arbitrate writers */ chain->reap = NULL; /* prepare for deletions */ switch (cmd) { case 0: /* delete rules "num" (num == 0 matches all) */ case 1: /* delete all rules in set N */ case 5: /* delete rules with number N and set "new_set". */ /* * Locate first rule to delete (start), the rule after * the last one to delete (end), and count how many * rules to delete (n). Always use keep_rule() to * determine which rules to keep. */ n = 0; if (cmd == 1) { /* look for a specific set including RESVD_SET. * Must scan the entire range, ignore num. */ new_set = num; for (start = -1, end = i = 0; i < chain->n_rules; i++) { if (keep_rule(chain->map[i], cmd, new_set, 0)) continue; if (start < 0) start = i; end = i; n++; } end++; /* first non-matching */ } else { /* Optimized search on rule numbers */ start = ipfw_find_rule(chain, num, 0); for (end = start; end < chain->n_rules; end++) { rule = chain->map[end]; if (num > 0 && rule->rulenum != num) break; if (!keep_rule(rule, cmd, new_set, num)) n++; } } if (n == 0) { /* A flush request (arg == 0 or cmd == 1) on empty * ruleset returns with no error. On the contrary, * if there is no match on a specific request, * we return EINVAL. */ if (arg != 0 && cmd != 1) error = EINVAL; break; } /* We have something to delete. Allocate the new map */ map = get_map(chain, -n, 1 /* locked */); if (map == NULL) { error = EINVAL; break; } /* 1. bcopy the initial part of the map */ if (start > 0) bcopy(chain->map, map, start * sizeof(struct ip_fw *)); /* 2. copy active rules between start and end */ for (i = ofs = start; i < end; i++) { rule = chain->map[i]; if (keep_rule(rule, cmd, new_set, num)) map[ofs++] = rule; } /* 3. copy the final part of the map */ bcopy(chain->map + end, map + ofs, (chain->n_rules - end) * sizeof(struct ip_fw *)); /* 4. swap the maps (under BH_LOCK) */ map = swap_map(chain, map, chain->n_rules - n); /* 5. now remove the rules deleted from the old map */ for (i = start; i < end; i++) { int l; rule = map[i]; if (keep_rule(rule, cmd, new_set, num)) continue; l = RULESIZE(rule); chain->static_len -= l; ipfw_remove_dyn_children(rule); rule->x_next = chain->reap; chain->reap = rule; } break; /* * In the next 3 cases the loop stops at (n_rules - 1) * because the default rule is never eligible.. */ case 2: /* move rules with given RULE number to new set */ for (i = 0; i < chain->n_rules - 1; i++) { rule = chain->map[i]; if (rule->rulenum == num) rule->set = new_set; } break; case 3: /* move rules with given SET number to new set */ for (i = 0; i < chain->n_rules - 1; i++) { rule = chain->map[i]; if (rule->set == num) rule->set = new_set; } break; case 4: /* swap two sets */ for (i = 0; i < chain->n_rules - 1; i++) { rule = chain->map[i]; if (rule->set == num) rule->set = new_set; else if (rule->set == new_set) rule->set = num; } break; } rule = chain->reap; chain->reap = NULL; IPFW_UH_WUNLOCK(chain); ipfw_reap_rules(rule); if (map) free(map, M_IPFW); return error; } /* * Clear counters for a specific rule. * Normally run under IPFW_UH_RLOCK, but these are idempotent ops * so we only care that rules do not disappear. */ 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; int i; 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_UH_RLOCK(chain); if (rulenum == 0) { V_norule_counter = 0; for (i = 0; i < chain->n_rules; i++) { rule = chain->map[i]; /* Skip rules not in our 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; for (i = 0; i < chain->n_rules; i++) { rule = chain->map[i]; if (rule->rulenum == rulenum) { if (cmd == 0 || rule->set == set) clear_counters(rule, log_only); cleared = 1; } if (rule->rulenum > rulenum) break; } if (!cleared) { /* we did not find any matching rules */ IPFW_UH_RUNLOCK(chain); return (EINVAL); } msg = log_only ? "logging count reset" : "cleared"; } IPFW_UH_RUNLOCK(chain); if (V_fw_verbose) { int 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. * 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; } 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_SOCKARG: 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 != IP_FW_TABLEARG) && (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) + 1 && 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 #ifdef INET6 case O_FORWARD_IP6: #ifdef IPFIREWALL_FORWARD if (cmdlen != F_INSN_SIZE(ipfw_insn_sa6)) goto bad_size; goto check_action; #else return (EINVAL); #endif #endif /* INET6 */ 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_input_p == NULL) 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: case O_REASS: case O_CALLRETURN: 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; } /* * Translation of requests for compatibility with FreeBSD 7.2/8. * a static variable tells us if we have an old client from userland, * and if necessary we translate requests and responses between the * two formats. */ static int is7 = 0; struct ip_fw7 { struct ip_fw7 *next; /* linked list of rules */ struct ip_fw7 *next_rule; /* ptr to next [skipto] rule */ /* 'next_rule' is used to pass up 'set_disable' status */ uint16_t act_ofs; /* offset of action in 32-bit units */ uint16_t cmd_len; /* # of 32-bit words in cmd */ uint16_t rulenum; /* rule number */ uint8_t set; /* rule set (0..31) */ // #define RESVD_SET 31 /* set for default and persistent rules */ uint8_t _pad; /* padding */ // uint32_t id; /* rule id, only in v.8 */ /* These fields are present in all rules. */ uint64_t pcnt; /* Packet counter */ uint64_t bcnt; /* Byte counter */ uint32_t timestamp; /* tv_sec of last match */ ipfw_insn cmd[1]; /* storage for commands */ }; int convert_rule_to_7(struct ip_fw *rule); int convert_rule_to_8(struct ip_fw *rule); #ifndef RULESIZE7 #define RULESIZE7(rule) (sizeof(struct ip_fw7) + \ ((struct ip_fw7 *)(rule))->cmd_len * 4 - 4) #endif /* * Copy the static and dynamic rules to the supplied buffer * and return the amount of space actually used. * Must be run under IPFW_UH_RLOCK */ 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, *dst; int l, i; time_t boot_seconds; boot_seconds = boottime.tv_sec; for (i = 0; i < chain->n_rules; i++) { rule = chain->map[i]; if (is7) { /* Convert rule to FreeBSd 7.2 format */ l = RULESIZE7(rule); if (bp + l + sizeof(uint32_t) <= ep) { int error; bcopy(rule, bp, l + sizeof(uint32_t)); error = convert_rule_to_7((struct ip_fw *) bp); if (error) return 0; /*XXX correct? */ /* * 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(&V_set_disable, &(((struct ip_fw7 *)bp)->next_rule), sizeof(V_set_disable)); if (((struct ip_fw7 *)bp)->timestamp) ((struct ip_fw7 *)bp)->timestamp += boot_seconds; bp += l; } continue; /* go to next rule */ } /* normal mode, don't touch rules */ l = RULESIZE(rule); if (bp + l > ep) { /* should not happen */ printf("overflow dumping static rules\n"); break; } dst = (struct ip_fw *)bp; bcopy(rule, dst, l); /* * 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(&V_set_disable, &dst->next_rule, sizeof(V_set_disable)); if (dst->timestamp) dst->timestamp += boot_seconds; bp += l; } ipfw_get_dynamic(&bp, ep); /* protected by the dynamic lock */ return (bp - (char *)buf); } /** * {set|get}sockopt parser. */ int ipfw_ctl(struct sockopt *sopt) { #define RULE_MAXSIZE (256*sizeof(u_int32_t)) int error; size_t size; struct ip_fw *buf, *rule; struct ip_fw_chain *chain; 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); } chain = &V_layer3_chain; 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. */ for (;;) { int len = 0, want; size = chain->static_len; size += ipfw_dyn_len(); if (size >= sopt->sopt_valsize) break; buf = malloc(size, M_TEMP, M_WAITOK); if (buf == NULL) break; IPFW_UH_RLOCK(chain); /* check again how much space we need */ want = chain->static_len + ipfw_dyn_len(); if (size >= want) len = ipfw_getrules(chain, buf, size); IPFW_UH_RUNLOCK(chain); if (size >= want) error = sooptcopyout(sopt, buf, len); free(buf, M_TEMP); if (size >= want) break; } break; case IP_FW_FLUSH: /* locking is done within del_entry() */ error = del_entry(chain, 0); /* special case, rule=0, cmd=0 means all */ break; case IP_FW_ADD: rule = malloc(RULE_MAXSIZE, M_TEMP, M_WAITOK); error = sooptcopyin(sopt, rule, RULE_MAXSIZE, sizeof(struct ip_fw7) ); /* * If the size of commands equals RULESIZE7 then we assume * a FreeBSD7.2 binary is talking to us (set is7=1). * is7 is persistent so the next 'ipfw list' command * will use this format. * NOTE: If wrong version is guessed (this can happen if * the first ipfw command is 'ipfw [pipe] list') * the ipfw binary may crash or loop infinitly... */ if (sopt->sopt_valsize == RULESIZE7(rule)) { is7 = 1; error = convert_rule_to_8(rule); if (error) return error; if (error == 0) error = check_ipfw_struct(rule, RULESIZE(rule)); } else { is7 = 0; if (error == 0) error = check_ipfw_struct(rule, sopt->sopt_valsize); } if (error == 0) { /* locking is done within ipfw_add_rule() */ error = ipfw_add_rule(chain, rule); size = RULESIZE(rule); if (!error && sopt->sopt_dir == SOPT_GET) { if (is7) { error = convert_rule_to_7(rule); size = RULESIZE7(rule); if (error) return error; } 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) && rulenum[0] != 0) { /* delete or reassign, locking done in del_entry() */ error = del_entry(chain, rulenum[0]); } else if (size == 2*sizeof(u_int32_t)) { /* set enable/disable */ IPFW_UH_WLOCK(chain); V_set_disable = (V_set_disable | rulenum[0]) & ~rulenum[1] & ~(1<sopt_val != 0) { error = sooptcopyin(sopt, rulenum, sizeof(u_int32_t), sizeof(u_int32_t)); if (error) break; } error = zero_entry(chain, rulenum[0], sopt->sopt_name == IP_FW_RESETLOG); break; /*--- TABLE manipulations are protected by the IPFW_LOCK ---*/ case IP_FW_TABLE_ADD: { ipfw_table_entry ent; error = sooptcopyin(sopt, &ent, sizeof(ent), sizeof(ent)); if (error) break; error = ipfw_add_table_entry(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 = ipfw_del_table_entry(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(chain); error = ipfw_flush_table(chain, tbl); IPFW_WUNLOCK(chain); } break; case IP_FW_TABLE_GETSIZE: { u_int32_t tbl, cnt; if ((error = sooptcopyin(sopt, &tbl, sizeof(tbl), sizeof(tbl)))) break; IPFW_RLOCK(chain); error = ipfw_count_table(chain, tbl, &cnt); IPFW_RUNLOCK(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(chain); error = ipfw_dump_table(chain, tbl); IPFW_RUNLOCK(chain); if (error) { free(tbl, M_TEMP); break; } error = sooptcopyout(sopt, tbl, size); free(tbl, M_TEMP); } break; /*--- NAT operations are protected by the IPFW_LOCK ---*/ 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 } #define RULE_MAXSIZE (256*sizeof(u_int32_t)) /* Functions to convert rules 7.2 <==> 8.0 */ int convert_rule_to_7(struct ip_fw *rule) { /* Used to modify original rule */ struct ip_fw7 *rule7 = (struct ip_fw7 *)rule; /* copy of original rule, version 8 */ struct ip_fw *tmp; /* Used to copy commands */ ipfw_insn *ccmd, *dst; int ll = 0, ccmdlen = 0; tmp = malloc(RULE_MAXSIZE, M_TEMP, M_NOWAIT | M_ZERO); if (tmp == NULL) { return 1; //XXX error } bcopy(rule, tmp, RULE_MAXSIZE); /* Copy fields */ rule7->_pad = tmp->_pad; rule7->set = tmp->set; rule7->rulenum = tmp->rulenum; rule7->cmd_len = tmp->cmd_len; rule7->act_ofs = tmp->act_ofs; rule7->next_rule = (struct ip_fw7 *)tmp->next_rule; rule7->next = (struct ip_fw7 *)tmp->x_next; rule7->cmd_len = tmp->cmd_len; rule7->pcnt = tmp->pcnt; rule7->bcnt = tmp->bcnt; rule7->timestamp = tmp->timestamp; /* Copy commands */ for (ll = tmp->cmd_len, ccmd = tmp->cmd, dst = rule7->cmd ; ll > 0 ; ll -= ccmdlen, ccmd += ccmdlen, dst += ccmdlen) { ccmdlen = F_LEN(ccmd); bcopy(ccmd, dst, F_LEN(ccmd)*sizeof(uint32_t)); if (dst->opcode > O_NAT) /* O_REASS doesn't exists in 7.2 version, so * decrement opcode if it is after O_REASS */ dst->opcode--; if (ccmdlen > ll) { printf("ipfw: opcode %d size truncated\n", ccmd->opcode); return EINVAL; } } free(tmp, M_TEMP); return 0; } int convert_rule_to_8(struct ip_fw *rule) { /* Used to modify original rule */ struct ip_fw7 *rule7 = (struct ip_fw7 *) rule; /* Used to copy commands */ ipfw_insn *ccmd, *dst; int ll = 0, ccmdlen = 0; /* Copy of original rule */ struct ip_fw7 *tmp = malloc(RULE_MAXSIZE, M_TEMP, M_NOWAIT | M_ZERO); if (tmp == NULL) { return 1; //XXX error } bcopy(rule7, tmp, RULE_MAXSIZE); for (ll = tmp->cmd_len, ccmd = tmp->cmd, dst = rule->cmd ; ll > 0 ; ll -= ccmdlen, ccmd += ccmdlen, dst += ccmdlen) { ccmdlen = F_LEN(ccmd); bcopy(ccmd, dst, F_LEN(ccmd)*sizeof(uint32_t)); if (dst->opcode > O_NAT) /* O_REASS doesn't exists in 7.2 version, so * increment opcode if it is after O_REASS */ dst->opcode++; if (ccmdlen > ll) { printf("ipfw: opcode %d size truncated\n", ccmd->opcode); return EINVAL; } } rule->_pad = tmp->_pad; rule->set = tmp->set; rule->rulenum = tmp->rulenum; rule->cmd_len = tmp->cmd_len; rule->act_ofs = tmp->act_ofs; rule->next_rule = (struct ip_fw *)tmp->next_rule; rule->x_next = (struct ip_fw *)tmp->next; rule->cmd_len = tmp->cmd_len; rule->id = 0; /* XXX see if is ok = 0 */ rule->pcnt = tmp->pcnt; rule->bcnt = tmp->bcnt; rule->timestamp = tmp->timestamp; free (tmp, M_TEMP); return 0; } /* end of file */ diff --git a/sys/netinet/ipfw/ip_fw_table.c b/sys/netinet/ipfw/ip_fw_table.c index 517622f02171..f72401765a19 100644 --- a/sys/netinet/ipfw/ip_fw_table.c +++ b/sys/netinet/ipfw/ip_fw_table.c @@ -1,286 +1,286 @@ /*- * Copyright (c) 2004 Ruslan Ermilov and Vsevolod Lobko. * * 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 __FBSDID("$FreeBSD$"); /* * Lookup table support for ipfw * * Lookup tables are implemented (at the moment) using the radix * tree used for routing tables. Tables store key-value entries, where * keys are network prefixes (addr/masklen), and values are integers. * As a degenerate case we can interpret keys as 32-bit integers * (with a /32 mask). * * The table is protected by the IPFW lock even for manipulation coming * from userland, because operations are typically fast. */ -#if !defined(KLD_MODULE) #include "opt_ipfw.h" +#if !defined(KLD_MODULE) #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 #include #include #include #include #include #include #include /* ip_fw.h requires IFNAMSIZ */ #include #include #include #include #include /* struct ipfw_rule_ref */ #include #include /* LIST_HEAD */ #include #ifdef MAC #include #endif MALLOC_DEFINE(M_IPFW_TBL, "ipfw_tbl", "IpFw tables"); struct table_entry { struct radix_node rn[2]; struct sockaddr_in addr, mask; u_int32_t value; }; /* * The radix code expects addr and mask to be array of bytes, * with the first byte being the length of the array. rn_inithead * is called with the offset in bits of the lookup key within the * array. If we use a sockaddr_in as the underlying type, * sin_len is conveniently located at offset 0, sin_addr is at * offset 4 and normally aligned. * But for portability, let's avoid assumption and make the code explicit */ #define KEY_LEN(v) *((uint8_t *)&(v)) #define KEY_OFS (8*offsetof(struct sockaddr_in, sin_addr)) int ipfw_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; KEY_LEN(ent->addr) = KEY_LEN(ent->mask) = 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); } int ipfw_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]; KEY_LEN(sa) = KEY_LEN(mask) = 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); } int ipfw_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); } void ipfw_destroy_tables(struct ip_fw_chain *ch) { uint16_t tbl; struct radix_node_head *rnh; IPFW_WLOCK_ASSERT(ch); for (tbl = 0; tbl < IPFW_TABLES_MAX; tbl++) { ipfw_flush_table(ch, tbl); rnh = ch->tables[tbl]; rn_detachhead((void **)&rnh); } } int ipfw_init_tables(struct ip_fw_chain *ch) { int i; uint16_t j; for (i = 0; i < IPFW_TABLES_MAX; i++) { if (!rn_inithead((void **)&ch->tables[i], KEY_OFS)) { for (j = 0; j < i; j++) { (void) ipfw_flush_table(ch, j); } return (ENOMEM); } } return (0); } int ipfw_lookup_table(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr, uint32_t *val) { struct radix_node_head *rnh; struct table_entry *ent; struct sockaddr_in sa; if (tbl >= IPFW_TABLES_MAX) return (0); rnh = ch->tables[tbl]; KEY_LEN(sa) = 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); } return (0); } static int count_table_entry(struct radix_node *rn, void *arg) { u_int32_t * const cnt = arg; (*cnt)++; return (0); } int ipfw_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); } int ipfw_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); } /* end of file */