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unneback |
/*
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* Copyright (c) 1996 Alex Nash
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* Copyright (c) 1993 Daniel Boulet
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* Copyright (c) 1994 Ugen J.S.Antsilevich
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*
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* Redistribution and use in source forms, with and without modification,
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* are permitted provided that this entire comment appears intact.
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*
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* Redistribution in binary form may occur without any restrictions.
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* Obviously, it would be nice if you gave credit where credit is due
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* but requiring it would be too onerous.
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*
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* This software is provided ``AS IS'' without any warranties of any kind.
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*
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* $Id: ip_fw.c,v 1.2 2001-09-27 12:01:55 chris Exp $
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*/
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/*
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* Implement IP packet firewall
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*/
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#ifndef IPFIREWALL_MODULE
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#include "opt_ipfw.h"
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#endif
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/malloc.h>
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#include <sys/mbuf.h>
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#include <sys/queue.h>
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#include <sys/kernel.h>
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#include <sys/socket.h>
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#include <sys/time.h>
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#include <sys/sysctl.h>
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#include <net/if.h>
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#include <net/route.h>
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#include <netinet/in.h>
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#include <netinet/in_systm.h>
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#include <netinet/ip.h>
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#include <netinet/ip_var.h>
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#include <netinet/ip_icmp.h>
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#include <netinet/ip_fw.h>
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#include <netinet/tcp.h>
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#include <netinet/tcp_timer.h>
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#include <netinet/tcp_var.h>
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#include <netinet/tcpip.h>
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#include <netinet/udp.h>
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static int fw_debug = 1;
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#ifdef IPFIREWALL_VERBOSE
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static int fw_verbose = 1;
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#else
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static int fw_verbose = 0;
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#endif
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#ifdef IPFIREWALL_VERBOSE_LIMIT
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static int fw_verbose_limit = IPFIREWALL_VERBOSE_LIMIT;
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#else
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static int fw_verbose_limit = 0;
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#endif
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LIST_HEAD (ip_fw_head, ip_fw_chain) ip_fw_chain;
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#ifdef SYSCTL_NODE
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SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall");
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SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, debug, CTLFLAG_RW, &fw_debug, 0, "");
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SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose, CTLFLAG_RW, &fw_verbose, 0, "");
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SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit, CTLFLAG_RW, &fw_verbose_limit, 0, "");
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#endif
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#define dprintf(a) if (!fw_debug); else printf a
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#define print_ip(a) printf("%ld.%ld.%ld.%ld",(ntohl(a.s_addr)>>24)&0xFF,\
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(ntohl(a.s_addr)>>16)&0xFF,\
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(ntohl(a.s_addr)>>8)&0xFF,\
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(ntohl(a.s_addr))&0xFF);
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#define dprint_ip(a) if (!fw_debug); else print_ip(a)
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static int add_entry __P((struct ip_fw_head *chainptr, struct ip_fw *frwl));
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static int del_entry __P((struct ip_fw_head *chainptr, u_short number));
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static int zero_entry __P((struct mbuf *m));
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static struct ip_fw *check_ipfw_struct __P((struct ip_fw *m));
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static struct ip_fw *check_ipfw_mbuf __P((struct mbuf *fw));
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static int ipopts_match __P((struct ip *ip, struct ip_fw *f));
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static int port_match __P((u_short *portptr, int nports, u_short port,
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int range_flag));
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static int tcpflg_match __P((struct tcphdr *tcp, struct ip_fw *f));
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static int icmptype_match __P((struct icmp * icmp, struct ip_fw * f));
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static void ipfw_report __P((struct ip_fw *f, struct ip *ip,
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struct ifnet *rif, struct ifnet *oif));
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#ifdef IPFIREWALL_MODULE
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static ip_fw_chk_t *old_chk_ptr;
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static ip_fw_ctl_t *old_ctl_ptr;
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#endif
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static int ip_fw_chk __P((struct ip **pip, int hlen,
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struct ifnet *oif, int ignport, struct mbuf **m));
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static int ip_fw_ctl __P((int stage, struct mbuf **mm));
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static char err_prefix[] = "ip_fw_ctl:";
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/*
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* Returns 1 if the port is matched by the vector, 0 otherwise
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*/
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static inline int
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port_match(u_short *portptr, int nports, u_short port, int range_flag)
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{
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if (!nports)
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return 1;
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if (range_flag) {
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if (portptr[0] <= port && port <= portptr[1]) {
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return 1;
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}
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nports -= 2;
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portptr += 2;
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}
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while (nports-- > 0) {
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if (*portptr++ == port) {
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return 1;
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}
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}
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return 0;
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}
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static int
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tcpflg_match(struct tcphdr *tcp, struct ip_fw *f)
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{
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u_char flg_set, flg_clr;
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if ((f->fw_tcpf & IP_FW_TCPF_ESTAB) &&
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(tcp->th_flags & (IP_FW_TCPF_RST | IP_FW_TCPF_ACK)))
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return 1;
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flg_set = tcp->th_flags & f->fw_tcpf;
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flg_clr = tcp->th_flags & f->fw_tcpnf;
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if (flg_set != f->fw_tcpf)
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return 0;
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if (flg_clr)
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return 0;
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return 1;
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}
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static int
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icmptype_match(struct icmp *icmp, struct ip_fw *f)
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{
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int type;
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if (!(f->fw_flg & IP_FW_F_ICMPBIT))
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return(1);
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type = icmp->icmp_type;
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/* check for matching type in the bitmap */
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if (type < IP_FW_ICMPTYPES_DIM * sizeof(unsigned) * 8 &&
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(f->fw_icmptypes[type / (sizeof(unsigned) * 8)] &
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(1U << (type % (8 * sizeof(unsigned))))))
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return(1);
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return(0); /* no match */
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}
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static int
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ipopts_match(struct ip *ip, struct ip_fw *f)
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{
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register u_char *cp;
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int opt, optlen, cnt;
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u_char opts, nopts, nopts_sve;
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cp = (u_char *)(ip + 1);
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cnt = (ip->ip_hl << 2) - sizeof (struct ip);
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opts = f->fw_ipopt;
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nopts = nopts_sve = f->fw_ipnopt;
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for (; cnt > 0; cnt -= optlen, cp += optlen) {
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opt = cp[IPOPT_OPTVAL];
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if (opt == IPOPT_EOL)
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break;
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if (opt == IPOPT_NOP)
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optlen = 1;
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else {
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optlen = cp[IPOPT_OLEN];
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if (optlen <= 0 || optlen > cnt) {
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return 0; /*XXX*/
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}
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}
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switch (opt) {
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default:
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break;
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| 194 |
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case IPOPT_LSRR:
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opts &= ~IP_FW_IPOPT_LSRR;
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nopts &= ~IP_FW_IPOPT_LSRR;
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break;
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| 198 |
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| 199 |
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case IPOPT_SSRR:
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opts &= ~IP_FW_IPOPT_SSRR;
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nopts &= ~IP_FW_IPOPT_SSRR;
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break;
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| 203 |
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| 204 |
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case IPOPT_RR:
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opts &= ~IP_FW_IPOPT_RR;
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nopts &= ~IP_FW_IPOPT_RR;
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break;
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| 208 |
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case IPOPT_TS:
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opts &= ~IP_FW_IPOPT_TS;
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nopts &= ~IP_FW_IPOPT_TS;
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break;
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| 212 |
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}
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| 213 |
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if (opts == nopts)
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break;
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| 215 |
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}
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| 216 |
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if (opts == 0 && nopts == nopts_sve)
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| 217 |
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return 1;
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| 218 |
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else
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| 219 |
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return 0;
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| 220 |
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}
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| 221 |
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| 222 |
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static inline int
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| 223 |
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iface_match(struct ifnet *ifp, union ip_fw_if *ifu, int byname)
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| 224 |
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{
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| 225 |
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/* Check by name or by IP address */
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| 226 |
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if (byname) {
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| 227 |
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/* Check unit number (-1 is wildcard) */
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| 228 |
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if (ifu->fu_via_if.unit != -1
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| 229 |
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&& ifp->if_unit != ifu->fu_via_if.unit)
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| 230 |
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return(0);
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| 231 |
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/* Check name */
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| 232 |
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if (strncmp(ifp->if_name, ifu->fu_via_if.name, FW_IFNLEN))
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| 233 |
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return(0);
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| 234 |
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return(1);
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| 235 |
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} else if (ifu->fu_via_ip.s_addr != 0) { /* Zero == wildcard */
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| 236 |
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struct ifaddr *ia;
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| 237 |
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| 238 |
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for (ia = ifp->if_addrlist; ia; ia = ia->ifa_next) {
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| 239 |
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if (ia->ifa_addr == NULL)
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| 240 |
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continue;
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| 241 |
|
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if (ia->ifa_addr->sa_family != AF_INET)
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| 242 |
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continue;
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| 243 |
|
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if (ifu->fu_via_ip.s_addr != ((struct sockaddr_in *)
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| 244 |
|
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(ia->ifa_addr))->sin_addr.s_addr)
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| 245 |
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continue;
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| 246 |
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return(1);
|
| 247 |
|
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}
|
| 248 |
|
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return(0);
|
| 249 |
|
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}
|
| 250 |
|
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return(1);
|
| 251 |
|
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}
|
| 252 |
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| 253 |
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static void
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| 254 |
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ipfw_report(struct ip_fw *f, struct ip *ip,
|
| 255 |
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struct ifnet *rif, struct ifnet *oif)
|
| 256 |
|
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{
|
| 257 |
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static int counter;
|
| 258 |
|
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struct tcphdr *const tcp = (struct tcphdr *) ((u_long *) ip+ ip->ip_hl);
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| 259 |
|
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struct udphdr *const udp = (struct udphdr *) ((u_long *) ip+ ip->ip_hl);
|
| 260 |
|
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struct icmp *const icmp = (struct icmp *) ((u_long *) ip + ip->ip_hl);
|
| 261 |
|
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int count;
|
| 262 |
|
|
|
| 263 |
|
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count = f ? f->fw_pcnt : ++counter;
|
| 264 |
|
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if (fw_verbose_limit != 0 && count > fw_verbose_limit)
|
| 265 |
|
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return;
|
| 266 |
|
|
|
| 267 |
|
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/* Print command name */
|
| 268 |
|
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printf("ipfw: %d ", f ? f->fw_number : -1);
|
| 269 |
|
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if (!f)
|
| 270 |
|
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printf("Refuse");
|
| 271 |
|
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else
|
| 272 |
|
|
switch (f->fw_flg & IP_FW_F_COMMAND) {
|
| 273 |
|
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case IP_FW_F_DENY:
|
| 274 |
|
|
printf("Deny");
|
| 275 |
|
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break;
|
| 276 |
|
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case IP_FW_F_REJECT:
|
| 277 |
|
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if (f->fw_reject_code == IP_FW_REJECT_RST)
|
| 278 |
|
|
printf("Reset");
|
| 279 |
|
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else
|
| 280 |
|
|
printf("Unreach");
|
| 281 |
|
|
break;
|
| 282 |
|
|
case IP_FW_F_ACCEPT:
|
| 283 |
|
|
printf("Accept");
|
| 284 |
|
|
break;
|
| 285 |
|
|
case IP_FW_F_COUNT:
|
| 286 |
|
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printf("Count");
|
| 287 |
|
|
break;
|
| 288 |
|
|
case IP_FW_F_DIVERT:
|
| 289 |
|
|
printf("Divert %d", f->fw_divert_port);
|
| 290 |
|
|
break;
|
| 291 |
|
|
case IP_FW_F_TEE:
|
| 292 |
|
|
printf("Tee %d", f->fw_divert_port);
|
| 293 |
|
|
break;
|
| 294 |
|
|
case IP_FW_F_SKIPTO:
|
| 295 |
|
|
printf("SkipTo %d", f->fw_skipto_rule);
|
| 296 |
|
|
break;
|
| 297 |
|
|
default:
|
| 298 |
|
|
printf("UNKNOWN");
|
| 299 |
|
|
break;
|
| 300 |
|
|
}
|
| 301 |
|
|
printf(" ");
|
| 302 |
|
|
|
| 303 |
|
|
switch (ip->ip_p) {
|
| 304 |
|
|
case IPPROTO_TCP:
|
| 305 |
|
|
printf("TCP ");
|
| 306 |
|
|
print_ip(ip->ip_src);
|
| 307 |
|
|
if ((ip->ip_off & IP_OFFMASK) == 0)
|
| 308 |
|
|
printf(":%d ", ntohs(tcp->th_sport));
|
| 309 |
|
|
else
|
| 310 |
|
|
printf(" ");
|
| 311 |
|
|
print_ip(ip->ip_dst);
|
| 312 |
|
|
if ((ip->ip_off & IP_OFFMASK) == 0)
|
| 313 |
|
|
printf(":%d", ntohs(tcp->th_dport));
|
| 314 |
|
|
break;
|
| 315 |
|
|
case IPPROTO_UDP:
|
| 316 |
|
|
printf("UDP ");
|
| 317 |
|
|
print_ip(ip->ip_src);
|
| 318 |
|
|
if ((ip->ip_off & IP_OFFMASK) == 0)
|
| 319 |
|
|
printf(":%d ", ntohs(udp->uh_sport));
|
| 320 |
|
|
else
|
| 321 |
|
|
printf(" ");
|
| 322 |
|
|
print_ip(ip->ip_dst);
|
| 323 |
|
|
if ((ip->ip_off & IP_OFFMASK) == 0)
|
| 324 |
|
|
printf(":%d", ntohs(udp->uh_dport));
|
| 325 |
|
|
break;
|
| 326 |
|
|
case IPPROTO_ICMP:
|
| 327 |
|
|
printf("ICMP:%u.%u ", icmp->icmp_type, icmp->icmp_code);
|
| 328 |
|
|
print_ip(ip->ip_src);
|
| 329 |
|
|
printf(" ");
|
| 330 |
|
|
print_ip(ip->ip_dst);
|
| 331 |
|
|
break;
|
| 332 |
|
|
default:
|
| 333 |
|
|
printf("P:%d ", ip->ip_p);
|
| 334 |
|
|
print_ip(ip->ip_src);
|
| 335 |
|
|
printf(" ");
|
| 336 |
|
|
print_ip(ip->ip_dst);
|
| 337 |
|
|
break;
|
| 338 |
|
|
}
|
| 339 |
|
|
if (oif)
|
| 340 |
|
|
printf(" out via %s%d", oif->if_name, oif->if_unit);
|
| 341 |
|
|
else if (rif)
|
| 342 |
|
|
printf(" in via %s%d", rif->if_name, rif->if_unit);
|
| 343 |
|
|
if ((ip->ip_off & IP_OFFMASK))
|
| 344 |
|
|
printf(" Fragment = %d",ip->ip_off & IP_OFFMASK);
|
| 345 |
|
|
printf("\n");
|
| 346 |
|
|
if (fw_verbose_limit != 0 && count == fw_verbose_limit)
|
| 347 |
|
|
printf("ipfw: limit reached on rule #%d\n",
|
| 348 |
|
|
f ? f->fw_number : -1);
|
| 349 |
|
|
}
|
| 350 |
|
|
|
| 351 |
|
|
/*
|
| 352 |
|
|
* Parameters:
|
| 353 |
|
|
*
|
| 354 |
|
|
* ip Pointer to packet header (struct ip *)
|
| 355 |
|
|
* hlen Packet header length
|
| 356 |
|
|
* oif Outgoing interface, or NULL if packet is incoming
|
| 357 |
|
|
* ignport Ignore all divert/tee rules to this port (if non-zero)
|
| 358 |
|
|
* *m The packet; we set to NULL when/if we nuke it.
|
| 359 |
|
|
*
|
| 360 |
|
|
* Return value:
|
| 361 |
|
|
*
|
| 362 |
|
|
* 0 The packet is to be accepted and routed normally OR
|
| 363 |
|
|
* the packet was denied/rejected and has been dropped;
|
| 364 |
|
|
* in the latter case, *m is equal to NULL upon return.
|
| 365 |
|
|
* port Divert the packet to port.
|
| 366 |
|
|
*/
|
| 367 |
|
|
|
| 368 |
|
|
static int
|
| 369 |
|
|
ip_fw_chk(struct ip **pip, int hlen,
|
| 370 |
|
|
struct ifnet *oif, int ignport, struct mbuf **m)
|
| 371 |
|
|
{
|
| 372 |
|
|
struct ip_fw_chain *chain;
|
| 373 |
|
|
struct ip_fw *rule = NULL;
|
| 374 |
|
|
struct ip *ip = *pip;
|
| 375 |
|
|
struct ifnet *const rif = (*m)->m_pkthdr.rcvif;
|
| 376 |
|
|
u_short offset = (ip->ip_off & IP_OFFMASK);
|
| 377 |
|
|
u_short src_port, dst_port;
|
| 378 |
|
|
|
| 379 |
|
|
/*
|
| 380 |
|
|
* Go down the chain, looking for enlightment
|
| 381 |
|
|
*/
|
| 382 |
|
|
for (chain=ip_fw_chain.lh_first; chain; chain = chain->chain.le_next) {
|
| 383 |
|
|
register struct ip_fw *const f = chain->rule;
|
| 384 |
|
|
|
| 385 |
|
|
/* Check direction inbound */
|
| 386 |
|
|
if (!oif && !(f->fw_flg & IP_FW_F_IN))
|
| 387 |
|
|
continue;
|
| 388 |
|
|
|
| 389 |
|
|
/* Check direction outbound */
|
| 390 |
|
|
if (oif && !(f->fw_flg & IP_FW_F_OUT))
|
| 391 |
|
|
continue;
|
| 392 |
|
|
|
| 393 |
|
|
/* Fragments */
|
| 394 |
|
|
if ((f->fw_flg & IP_FW_F_FRAG) && !(ip->ip_off & IP_OFFMASK))
|
| 395 |
|
|
continue;
|
| 396 |
|
|
|
| 397 |
|
|
/* If src-addr doesn't match, not this rule. */
|
| 398 |
|
|
if (((f->fw_flg & IP_FW_F_INVSRC) != 0) ^ ((ip->ip_src.s_addr
|
| 399 |
|
|
& f->fw_smsk.s_addr) != f->fw_src.s_addr))
|
| 400 |
|
|
continue;
|
| 401 |
|
|
|
| 402 |
|
|
/* If dest-addr doesn't match, not this rule. */
|
| 403 |
|
|
if (((f->fw_flg & IP_FW_F_INVDST) != 0) ^ ((ip->ip_dst.s_addr
|
| 404 |
|
|
& f->fw_dmsk.s_addr) != f->fw_dst.s_addr))
|
| 405 |
|
|
continue;
|
| 406 |
|
|
|
| 407 |
|
|
/* Interface check */
|
| 408 |
|
|
if ((f->fw_flg & IF_FW_F_VIAHACK) == IF_FW_F_VIAHACK) {
|
| 409 |
|
|
struct ifnet *const iface = oif ? oif : rif;
|
| 410 |
|
|
|
| 411 |
|
|
/* Backwards compatibility hack for "via" */
|
| 412 |
|
|
if (!iface || !iface_match(iface,
|
| 413 |
|
|
&f->fw_in_if, f->fw_flg & IP_FW_F_OIFNAME))
|
| 414 |
|
|
continue;
|
| 415 |
|
|
} else {
|
| 416 |
|
|
/* Check receive interface */
|
| 417 |
|
|
if ((f->fw_flg & IP_FW_F_IIFACE)
|
| 418 |
|
|
&& (!rif || !iface_match(rif,
|
| 419 |
|
|
&f->fw_in_if, f->fw_flg & IP_FW_F_IIFNAME)))
|
| 420 |
|
|
continue;
|
| 421 |
|
|
/* Check outgoing interface */
|
| 422 |
|
|
if ((f->fw_flg & IP_FW_F_OIFACE)
|
| 423 |
|
|
&& (!oif || !iface_match(oif,
|
| 424 |
|
|
&f->fw_out_if, f->fw_flg & IP_FW_F_OIFNAME)))
|
| 425 |
|
|
continue;
|
| 426 |
|
|
}
|
| 427 |
|
|
|
| 428 |
|
|
/* Check IP options */
|
| 429 |
|
|
if (f->fw_ipopt != f->fw_ipnopt && !ipopts_match(ip, f))
|
| 430 |
|
|
continue;
|
| 431 |
|
|
|
| 432 |
|
|
/* Check protocol; if wildcard, match */
|
| 433 |
|
|
if (f->fw_prot == IPPROTO_IP)
|
| 434 |
|
|
goto got_match;
|
| 435 |
|
|
|
| 436 |
|
|
/* If different, don't match */
|
| 437 |
|
|
if (ip->ip_p != f->fw_prot)
|
| 438 |
|
|
continue;
|
| 439 |
|
|
|
| 440 |
|
|
#define PULLUP_TO(len) do { \
|
| 441 |
|
|
if ((*m)->m_len < (len) \
|
| 442 |
|
|
&& (*m = m_pullup(*m, (len))) == 0) { \
|
| 443 |
|
|
goto bogusfrag; \
|
| 444 |
|
|
} \
|
| 445 |
|
|
*pip = ip = mtod(*m, struct ip *); \
|
| 446 |
|
|
offset = (ip->ip_off & IP_OFFMASK); \
|
| 447 |
|
|
} while (0)
|
| 448 |
|
|
|
| 449 |
|
|
/* Protocol specific checks */
|
| 450 |
|
|
switch (ip->ip_p) {
|
| 451 |
|
|
case IPPROTO_TCP:
|
| 452 |
|
|
{
|
| 453 |
|
|
struct tcphdr *tcp;
|
| 454 |
|
|
|
| 455 |
|
|
if (offset == 1) /* cf. RFC 1858 */
|
| 456 |
|
|
goto bogusfrag;
|
| 457 |
|
|
if (offset != 0) {
|
| 458 |
|
|
/*
|
| 459 |
|
|
* TCP flags and ports aren't available in this
|
| 460 |
|
|
* packet -- if this rule specified either one,
|
| 461 |
|
|
* we consider the rule a non-match.
|
| 462 |
|
|
*/
|
| 463 |
|
|
if (f->fw_nports != 0 ||
|
| 464 |
|
|
f->fw_tcpf != f->fw_tcpnf)
|
| 465 |
|
|
continue;
|
| 466 |
|
|
|
| 467 |
|
|
break;
|
| 468 |
|
|
}
|
| 469 |
|
|
PULLUP_TO(hlen + 14);
|
| 470 |
|
|
tcp = (struct tcphdr *) ((u_long *)ip + ip->ip_hl);
|
| 471 |
|
|
if (f->fw_tcpf != f->fw_tcpnf && !tcpflg_match(tcp, f))
|
| 472 |
|
|
continue;
|
| 473 |
|
|
src_port = ntohs(tcp->th_sport);
|
| 474 |
|
|
dst_port = ntohs(tcp->th_dport);
|
| 475 |
|
|
goto check_ports;
|
| 476 |
|
|
}
|
| 477 |
|
|
|
| 478 |
|
|
case IPPROTO_UDP:
|
| 479 |
|
|
{
|
| 480 |
|
|
struct udphdr *udp;
|
| 481 |
|
|
|
| 482 |
|
|
if (offset != 0) {
|
| 483 |
|
|
/*
|
| 484 |
|
|
* Port specification is unavailable -- if this
|
| 485 |
|
|
* rule specifies a port, we consider the rule
|
| 486 |
|
|
* a non-match.
|
| 487 |
|
|
*/
|
| 488 |
|
|
if (f->fw_nports != 0)
|
| 489 |
|
|
continue;
|
| 490 |
|
|
|
| 491 |
|
|
break;
|
| 492 |
|
|
}
|
| 493 |
|
|
PULLUP_TO(hlen + 4);
|
| 494 |
|
|
udp = (struct udphdr *) ((u_long *)ip + ip->ip_hl);
|
| 495 |
|
|
src_port = ntohs(udp->uh_sport);
|
| 496 |
|
|
dst_port = ntohs(udp->uh_dport);
|
| 497 |
|
|
check_ports:
|
| 498 |
|
|
if (!port_match(&f->fw_pts[0],
|
| 499 |
|
|
IP_FW_GETNSRCP(f), src_port,
|
| 500 |
|
|
f->fw_flg & IP_FW_F_SRNG))
|
| 501 |
|
|
continue;
|
| 502 |
|
|
if (!port_match(&f->fw_pts[IP_FW_GETNSRCP(f)],
|
| 503 |
|
|
IP_FW_GETNDSTP(f), dst_port,
|
| 504 |
|
|
f->fw_flg & IP_FW_F_DRNG))
|
| 505 |
|
|
continue;
|
| 506 |
|
|
break;
|
| 507 |
|
|
}
|
| 508 |
|
|
|
| 509 |
|
|
case IPPROTO_ICMP:
|
| 510 |
|
|
{
|
| 511 |
|
|
struct icmp *icmp;
|
| 512 |
|
|
|
| 513 |
|
|
if (offset != 0) /* Type isn't valid */
|
| 514 |
|
|
break;
|
| 515 |
|
|
PULLUP_TO(hlen + 2);
|
| 516 |
|
|
icmp = (struct icmp *) ((u_long *)ip + ip->ip_hl);
|
| 517 |
|
|
if (!icmptype_match(icmp, f))
|
| 518 |
|
|
continue;
|
| 519 |
|
|
break;
|
| 520 |
|
|
}
|
| 521 |
|
|
#undef PULLUP_TO
|
| 522 |
|
|
|
| 523 |
|
|
bogusfrag:
|
| 524 |
|
|
if (fw_verbose)
|
| 525 |
|
|
ipfw_report(NULL, ip, rif, oif);
|
| 526 |
|
|
goto dropit;
|
| 527 |
|
|
}
|
| 528 |
|
|
|
| 529 |
|
|
got_match:
|
| 530 |
|
|
/* Ignore divert/tee rule if socket port is "ignport" */
|
| 531 |
|
|
switch (f->fw_flg & IP_FW_F_COMMAND) {
|
| 532 |
|
|
case IP_FW_F_DIVERT:
|
| 533 |
|
|
case IP_FW_F_TEE:
|
| 534 |
|
|
if (f->fw_divert_port == ignport)
|
| 535 |
|
|
continue; /* ignore this rule */
|
| 536 |
|
|
break;
|
| 537 |
|
|
}
|
| 538 |
|
|
|
| 539 |
|
|
/* Update statistics */
|
| 540 |
|
|
f->fw_pcnt += 1;
|
| 541 |
|
|
f->fw_bcnt += ip->ip_len;
|
| 542 |
|
|
f->timestamp = rtems_bsdnet_seconds_since_boot();
|
| 543 |
|
|
|
| 544 |
|
|
/* Log to console if desired */
|
| 545 |
|
|
if ((f->fw_flg & IP_FW_F_PRN) && fw_verbose)
|
| 546 |
|
|
ipfw_report(f, ip, rif, oif);
|
| 547 |
|
|
|
| 548 |
|
|
/* Take appropriate action */
|
| 549 |
|
|
switch (f->fw_flg & IP_FW_F_COMMAND) {
|
| 550 |
|
|
case IP_FW_F_ACCEPT:
|
| 551 |
|
|
return(0);
|
| 552 |
|
|
case IP_FW_F_COUNT:
|
| 553 |
|
|
continue;
|
| 554 |
|
|
case IP_FW_F_DIVERT:
|
| 555 |
|
|
return(f->fw_divert_port);
|
| 556 |
|
|
case IP_FW_F_TEE:
|
| 557 |
|
|
/*
|
| 558 |
|
|
* XXX someday tee packet here, but beware that you
|
| 559 |
|
|
* can't use m_copym() or m_copypacket() because
|
| 560 |
|
|
* the divert input routine modifies the mbuf
|
| 561 |
|
|
* (and these routines only increment reference
|
| 562 |
|
|
* counts in the case of mbuf clusters), so need
|
| 563 |
|
|
* to write custom routine.
|
| 564 |
|
|
*/
|
| 565 |
|
|
continue;
|
| 566 |
|
|
case IP_FW_F_SKIPTO:
|
| 567 |
|
|
#ifdef DIAGNOSTIC
|
| 568 |
|
|
while (chain->chain.le_next
|
| 569 |
|
|
&& chain->chain.le_next->rule->fw_number
|
| 570 |
|
|
< f->fw_skipto_rule)
|
| 571 |
|
|
#else
|
| 572 |
|
|
while (chain->chain.le_next->rule->fw_number
|
| 573 |
|
|
< f->fw_skipto_rule)
|
| 574 |
|
|
#endif
|
| 575 |
|
|
chain = chain->chain.le_next;
|
| 576 |
|
|
continue;
|
| 577 |
|
|
}
|
| 578 |
|
|
|
| 579 |
|
|
/* Deny/reject this packet using this rule */
|
| 580 |
|
|
rule = f;
|
| 581 |
|
|
break;
|
| 582 |
|
|
}
|
| 583 |
|
|
|
| 584 |
|
|
#ifdef DIAGNOSTIC
|
| 585 |
|
|
/* Rule 65535 should always be there and should always match */
|
| 586 |
|
|
if (!chain)
|
| 587 |
|
|
panic("ip_fw: chain");
|
| 588 |
|
|
#endif
|
| 589 |
|
|
|
| 590 |
|
|
/*
|
| 591 |
|
|
* At this point, we're going to drop the packet.
|
| 592 |
|
|
* Send a reject notice if all of the following are true:
|
| 593 |
|
|
*
|
| 594 |
|
|
* - The packet matched a reject rule
|
| 595 |
|
|
* - The packet is not an ICMP packet
|
| 596 |
|
|
* - The packet is not a multicast or broadcast packet
|
| 597 |
|
|
*/
|
| 598 |
|
|
if ((rule->fw_flg & IP_FW_F_COMMAND) == IP_FW_F_REJECT
|
| 599 |
|
|
&& ip->ip_p != IPPROTO_ICMP
|
| 600 |
|
|
&& !((*m)->m_flags & (M_BCAST|M_MCAST))
|
| 601 |
|
|
&& !IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
|
| 602 |
|
|
switch (rule->fw_reject_code) {
|
| 603 |
|
|
case IP_FW_REJECT_RST:
|
| 604 |
|
|
{
|
| 605 |
|
|
struct tcphdr *const tcp =
|
| 606 |
|
|
(struct tcphdr *) ((u_long *)ip + ip->ip_hl);
|
| 607 |
|
|
struct tcpiphdr ti, *const tip = (struct tcpiphdr *) ip;
|
| 608 |
|
|
|
| 609 |
|
|
if (offset != 0 || (tcp->th_flags & TH_RST))
|
| 610 |
|
|
break;
|
| 611 |
|
|
ti.ti_i = *((struct ipovly *) ip);
|
| 612 |
|
|
ti.ti_t = *tcp;
|
| 613 |
|
|
bcopy(&ti, ip, sizeof(ti));
|
| 614 |
|
|
NTOHL(tip->ti_seq);
|
| 615 |
|
|
NTOHL(tip->ti_ack);
|
| 616 |
|
|
tip->ti_len = ip->ip_len - hlen - (tip->ti_off << 2);
|
| 617 |
|
|
if (tcp->th_flags & TH_ACK) {
|
| 618 |
|
|
tcp_respond(NULL, tip, *m,
|
| 619 |
|
|
(tcp_seq)0, ntohl(tcp->th_ack), TH_RST);
|
| 620 |
|
|
} else {
|
| 621 |
|
|
if (tcp->th_flags & TH_SYN)
|
| 622 |
|
|
tip->ti_len++;
|
| 623 |
|
|
tcp_respond(NULL, tip, *m, tip->ti_seq
|
| 624 |
|
|
+ tip->ti_len, (tcp_seq)0, TH_RST|TH_ACK);
|
| 625 |
|
|
}
|
| 626 |
|
|
*m = NULL;
|
| 627 |
|
|
break;
|
| 628 |
|
|
}
|
| 629 |
|
|
default: /* Send an ICMP unreachable using code */
|
| 630 |
|
|
icmp_error(*m, ICMP_UNREACH,
|
| 631 |
|
|
rule->fw_reject_code, 0L, 0);
|
| 632 |
|
|
*m = NULL;
|
| 633 |
|
|
break;
|
| 634 |
|
|
}
|
| 635 |
|
|
}
|
| 636 |
|
|
|
| 637 |
|
|
dropit:
|
| 638 |
|
|
/*
|
| 639 |
|
|
* Finally, drop the packet.
|
| 640 |
|
|
*/
|
| 641 |
|
|
if (*m) {
|
| 642 |
|
|
m_freem(*m);
|
| 643 |
|
|
*m = NULL;
|
| 644 |
|
|
}
|
| 645 |
|
|
return(0);
|
| 646 |
|
|
}
|
| 647 |
|
|
|
| 648 |
|
|
static int
|
| 649 |
|
|
add_entry(struct ip_fw_head *chainptr, struct ip_fw *frwl)
|
| 650 |
|
|
{
|
| 651 |
|
|
struct ip_fw *ftmp = 0;
|
| 652 |
|
|
struct ip_fw_chain *fwc = 0, *fcp, *fcpl = 0;
|
| 653 |
|
|
u_short nbr = 0;
|
| 654 |
|
|
int s;
|
| 655 |
|
|
|
| 656 |
|
|
fwc = malloc(sizeof *fwc, M_IPFW, M_DONTWAIT);
|
| 657 |
|
|
ftmp = malloc(sizeof *ftmp, M_IPFW, M_DONTWAIT);
|
| 658 |
|
|
if (!fwc || !ftmp) {
|
| 659 |
|
|
dprintf(("%s malloc said no\n", err_prefix));
|
| 660 |
|
|
if (fwc) free(fwc, M_IPFW);
|
| 661 |
|
|
if (ftmp) free(ftmp, M_IPFW);
|
| 662 |
|
|
return (ENOSPC);
|
| 663 |
|
|
}
|
| 664 |
|
|
|
| 665 |
|
|
bcopy(frwl, ftmp, sizeof(struct ip_fw));
|
| 666 |
|
|
ftmp->fw_in_if.fu_via_if.name[FW_IFNLEN - 1] = '\0';
|
| 667 |
|
|
ftmp->fw_pcnt = 0L;
|
| 668 |
|
|
ftmp->fw_bcnt = 0L;
|
| 669 |
|
|
fwc->rule = ftmp;
|
| 670 |
|
|
|
| 671 |
|
|
s = splnet();
|
| 672 |
|
|
|
| 673 |
|
|
if (!chainptr->lh_first) {
|
| 674 |
|
|
LIST_INSERT_HEAD(chainptr, fwc, chain);
|
| 675 |
|
|
splx(s);
|
| 676 |
|
|
return(0);
|
| 677 |
|
|
} else if (ftmp->fw_number == (u_short)-1) {
|
| 678 |
|
|
if (fwc) free(fwc, M_IPFW);
|
| 679 |
|
|
if (ftmp) free(ftmp, M_IPFW);
|
| 680 |
|
|
splx(s);
|
| 681 |
|
|
dprintf(("%s bad rule number\n", err_prefix));
|
| 682 |
|
|
return (EINVAL);
|
| 683 |
|
|
}
|
| 684 |
|
|
|
| 685 |
|
|
/* If entry number is 0, find highest numbered rule and add 100 */
|
| 686 |
|
|
if (ftmp->fw_number == 0) {
|
| 687 |
|
|
for (fcp = chainptr->lh_first; fcp; fcp = fcp->chain.le_next) {
|
| 688 |
|
|
if (fcp->rule->fw_number != (u_short)-1)
|
| 689 |
|
|
nbr = fcp->rule->fw_number;
|
| 690 |
|
|
else
|
| 691 |
|
|
break;
|
| 692 |
|
|
}
|
| 693 |
|
|
if (nbr < (u_short)-1 - 100)
|
| 694 |
|
|
nbr += 100;
|
| 695 |
|
|
ftmp->fw_number = nbr;
|
| 696 |
|
|
}
|
| 697 |
|
|
|
| 698 |
|
|
/* Got a valid number; now insert it, keeping the list ordered */
|
| 699 |
|
|
for (fcp = chainptr->lh_first; fcp; fcp = fcp->chain.le_next) {
|
| 700 |
|
|
if (fcp->rule->fw_number > ftmp->fw_number) {
|
| 701 |
|
|
if (fcpl) {
|
| 702 |
|
|
LIST_INSERT_AFTER(fcpl, fwc, chain);
|
| 703 |
|
|
} else {
|
| 704 |
|
|
LIST_INSERT_HEAD(chainptr, fwc, chain);
|
| 705 |
|
|
}
|
| 706 |
|
|
break;
|
| 707 |
|
|
} else {
|
| 708 |
|
|
fcpl = fcp;
|
| 709 |
|
|
}
|
| 710 |
|
|
}
|
| 711 |
|
|
|
| 712 |
|
|
splx(s);
|
| 713 |
|
|
return (0);
|
| 714 |
|
|
}
|
| 715 |
|
|
|
| 716 |
|
|
static int
|
| 717 |
|
|
del_entry(struct ip_fw_head *chainptr, u_short number)
|
| 718 |
|
|
{
|
| 719 |
|
|
struct ip_fw_chain *fcp;
|
| 720 |
|
|
int s;
|
| 721 |
|
|
|
| 722 |
|
|
s = splnet();
|
| 723 |
|
|
|
| 724 |
|
|
fcp = chainptr->lh_first;
|
| 725 |
|
|
if (number != (u_short)-1) {
|
| 726 |
|
|
for (; fcp; fcp = fcp->chain.le_next) {
|
| 727 |
|
|
if (fcp->rule->fw_number == number) {
|
| 728 |
|
|
LIST_REMOVE(fcp, chain);
|
| 729 |
|
|
splx(s);
|
| 730 |
|
|
free(fcp->rule, M_IPFW);
|
| 731 |
|
|
free(fcp, M_IPFW);
|
| 732 |
|
|
return 0;
|
| 733 |
|
|
}
|
| 734 |
|
|
}
|
| 735 |
|
|
}
|
| 736 |
|
|
|
| 737 |
|
|
splx(s);
|
| 738 |
|
|
return (EINVAL);
|
| 739 |
|
|
}
|
| 740 |
|
|
|
| 741 |
|
|
static int
|
| 742 |
|
|
zero_entry(struct mbuf *m)
|
| 743 |
|
|
{
|
| 744 |
|
|
struct ip_fw *frwl;
|
| 745 |
|
|
struct ip_fw_chain *fcp;
|
| 746 |
|
|
int s;
|
| 747 |
|
|
|
| 748 |
|
|
if (m) {
|
| 749 |
|
|
if (m->m_len != sizeof(struct ip_fw))
|
| 750 |
|
|
return(EINVAL);
|
| 751 |
|
|
frwl = mtod(m, struct ip_fw *);
|
| 752 |
|
|
}
|
| 753 |
|
|
else
|
| 754 |
|
|
frwl = NULL;
|
| 755 |
|
|
|
| 756 |
|
|
/*
|
| 757 |
|
|
* It's possible to insert multiple chain entries with the
|
| 758 |
|
|
* same number, so we don't stop after finding the first
|
| 759 |
|
|
* match if zeroing a specific entry.
|
| 760 |
|
|
*/
|
| 761 |
|
|
s = splnet();
|
| 762 |
|
|
for (fcp = ip_fw_chain.lh_first; fcp; fcp = fcp->chain.le_next)
|
| 763 |
|
|
if (!frwl || frwl->fw_number == fcp->rule->fw_number) {
|
| 764 |
|
|
fcp->rule->fw_bcnt = fcp->rule->fw_pcnt = 0;
|
| 765 |
|
|
fcp->rule->timestamp = 0;
|
| 766 |
|
|
}
|
| 767 |
|
|
splx(s);
|
| 768 |
|
|
|
| 769 |
|
|
if (fw_verbose) {
|
| 770 |
|
|
if (frwl)
|
| 771 |
|
|
printf("ipfw: Entry %d cleared.\n", frwl->fw_number);
|
| 772 |
|
|
else
|
| 773 |
|
|
printf("ipfw: Accounting cleared.\n");
|
| 774 |
|
|
}
|
| 775 |
|
|
|
| 776 |
|
|
return(0);
|
| 777 |
|
|
}
|
| 778 |
|
|
|
| 779 |
|
|
static struct ip_fw *
|
| 780 |
|
|
check_ipfw_mbuf(struct mbuf *m)
|
| 781 |
|
|
{
|
| 782 |
|
|
/* Check length */
|
| 783 |
|
|
if (m->m_len != sizeof(struct ip_fw)) {
|
| 784 |
|
|
dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len,
|
| 785 |
|
|
(int)sizeof(struct ip_fw)));
|
| 786 |
|
|
return (NULL);
|
| 787 |
|
|
}
|
| 788 |
|
|
return(check_ipfw_struct(mtod(m, struct ip_fw *)));
|
| 789 |
|
|
}
|
| 790 |
|
|
|
| 791 |
|
|
static struct ip_fw *
|
| 792 |
|
|
check_ipfw_struct(struct ip_fw *frwl)
|
| 793 |
|
|
{
|
| 794 |
|
|
/* Check for invalid flag bits */
|
| 795 |
|
|
if ((frwl->fw_flg & ~IP_FW_F_MASK) != 0) {
|
| 796 |
|
|
dprintf(("%s undefined flag bits set (flags=%x)\n",
|
| 797 |
|
|
err_prefix, frwl->fw_flg));
|
| 798 |
|
|
return (NULL);
|
| 799 |
|
|
}
|
| 800 |
|
|
/* Must apply to incoming or outgoing (or both) */
|
| 801 |
|
|
if (!(frwl->fw_flg & (IP_FW_F_IN | IP_FW_F_OUT))) {
|
| 802 |
|
|
dprintf(("%s neither in nor out\n", err_prefix));
|
| 803 |
|
|
return (NULL);
|
| 804 |
|
|
}
|
| 805 |
|
|
/* Empty interface name is no good */
|
| 806 |
|
|
if (((frwl->fw_flg & IP_FW_F_IIFNAME)
|
| 807 |
|
|
&& !*frwl->fw_in_if.fu_via_if.name)
|
| 808 |
|
|
|| ((frwl->fw_flg & IP_FW_F_OIFNAME)
|
| 809 |
|
|
&& !*frwl->fw_out_if.fu_via_if.name)) {
|
| 810 |
|
|
dprintf(("%s empty interface name\n", err_prefix));
|
| 811 |
|
|
return (NULL);
|
| 812 |
|
|
}
|
| 813 |
|
|
/* Sanity check interface matching */
|
| 814 |
|
|
if ((frwl->fw_flg & IF_FW_F_VIAHACK) == IF_FW_F_VIAHACK) {
|
| 815 |
|
|
; /* allow "via" backwards compatibility */
|
| 816 |
|
|
} else if ((frwl->fw_flg & IP_FW_F_IN)
|
| 817 |
|
|
&& (frwl->fw_flg & IP_FW_F_OIFACE)) {
|
| 818 |
|
|
dprintf(("%s outgoing interface check on incoming\n",
|
| 819 |
|
|
err_prefix));
|
| 820 |
|
|
return (NULL);
|
| 821 |
|
|
}
|
| 822 |
|
|
/* Sanity check port ranges */
|
| 823 |
|
|
if ((frwl->fw_flg & IP_FW_F_SRNG) && IP_FW_GETNSRCP(frwl) < 2) {
|
| 824 |
|
|
dprintf(("%s src range set but n_src_p=%d\n",
|
| 825 |
|
|
err_prefix, IP_FW_GETNSRCP(frwl)));
|
| 826 |
|
|
return (NULL);
|
| 827 |
|
|
}
|
| 828 |
|
|
if ((frwl->fw_flg & IP_FW_F_DRNG) && IP_FW_GETNDSTP(frwl) < 2) {
|
| 829 |
|
|
dprintf(("%s dst range set but n_dst_p=%d\n",
|
| 830 |
|
|
err_prefix, IP_FW_GETNDSTP(frwl)));
|
| 831 |
|
|
return (NULL);
|
| 832 |
|
|
}
|
| 833 |
|
|
if (IP_FW_GETNSRCP(frwl) + IP_FW_GETNDSTP(frwl) > IP_FW_MAX_PORTS) {
|
| 834 |
|
|
dprintf(("%s too many ports (%d+%d)\n",
|
| 835 |
|
|
err_prefix, IP_FW_GETNSRCP(frwl), IP_FW_GETNDSTP(frwl)));
|
| 836 |
|
|
return (NULL);
|
| 837 |
|
|
}
|
| 838 |
|
|
/*
|
| 839 |
|
|
* Protocols other than TCP/UDP don't use port range
|
| 840 |
|
|
*/
|
| 841 |
|
|
if ((frwl->fw_prot != IPPROTO_TCP) &&
|
| 842 |
|
|
(frwl->fw_prot != IPPROTO_UDP) &&
|
| 843 |
|
|
(IP_FW_GETNSRCP(frwl) || IP_FW_GETNDSTP(frwl))) {
|
| 844 |
|
|
dprintf(("%s port(s) specified for non TCP/UDP rule\n",
|
| 845 |
|
|
err_prefix));
|
| 846 |
|
|
return(NULL);
|
| 847 |
|
|
}
|
| 848 |
|
|
|
| 849 |
|
|
/*
|
| 850 |
|
|
* Rather than modify the entry to make such entries work,
|
| 851 |
|
|
* we reject this rule and require user level utilities
|
| 852 |
|
|
* to enforce whatever policy they deem appropriate.
|
| 853 |
|
|
*/
|
| 854 |
|
|
if ((frwl->fw_src.s_addr & (~frwl->fw_smsk.s_addr)) ||
|
| 855 |
|
|
(frwl->fw_dst.s_addr & (~frwl->fw_dmsk.s_addr))) {
|
| 856 |
|
|
dprintf(("%s rule never matches\n", err_prefix));
|
| 857 |
|
|
return(NULL);
|
| 858 |
|
|
}
|
| 859 |
|
|
|
| 860 |
|
|
if ((frwl->fw_flg & IP_FW_F_FRAG) &&
|
| 861 |
|
|
(frwl->fw_prot == IPPROTO_UDP || frwl->fw_prot == IPPROTO_TCP)) {
|
| 862 |
|
|
if (frwl->fw_nports) {
|
| 863 |
|
|
dprintf(("%s cannot mix 'frag' and ports\n", err_prefix));
|
| 864 |
|
|
return(NULL);
|
| 865 |
|
|
}
|
| 866 |
|
|
if (frwl->fw_prot == IPPROTO_TCP &&
|
| 867 |
|
|
frwl->fw_tcpf != frwl->fw_tcpnf) {
|
| 868 |
|
|
dprintf(("%s cannot mix 'frag' with TCP flags\n", err_prefix));
|
| 869 |
|
|
return(NULL);
|
| 870 |
|
|
}
|
| 871 |
|
|
}
|
| 872 |
|
|
|
| 873 |
|
|
/* Check command specific stuff */
|
| 874 |
|
|
switch (frwl->fw_flg & IP_FW_F_COMMAND)
|
| 875 |
|
|
{
|
| 876 |
|
|
case IP_FW_F_REJECT:
|
| 877 |
|
|
if (frwl->fw_reject_code >= 0x100
|
| 878 |
|
|
&& !(frwl->fw_prot == IPPROTO_TCP
|
| 879 |
|
|
&& frwl->fw_reject_code == IP_FW_REJECT_RST)) {
|
| 880 |
|
|
dprintf(("%s unknown reject code\n", err_prefix));
|
| 881 |
|
|
return(NULL);
|
| 882 |
|
|
}
|
| 883 |
|
|
break;
|
| 884 |
|
|
case IP_FW_F_DIVERT: /* Diverting to port zero is invalid */
|
| 885 |
|
|
case IP_FW_F_TEE:
|
| 886 |
|
|
if (frwl->fw_divert_port == 0) {
|
| 887 |
|
|
dprintf(("%s can't divert to port 0\n", err_prefix));
|
| 888 |
|
|
return (NULL);
|
| 889 |
|
|
}
|
| 890 |
|
|
break;
|
| 891 |
|
|
case IP_FW_F_DENY:
|
| 892 |
|
|
case IP_FW_F_ACCEPT:
|
| 893 |
|
|
case IP_FW_F_COUNT:
|
| 894 |
|
|
case IP_FW_F_SKIPTO:
|
| 895 |
|
|
break;
|
| 896 |
|
|
default:
|
| 897 |
|
|
dprintf(("%s invalid command\n", err_prefix));
|
| 898 |
|
|
return(NULL);
|
| 899 |
|
|
}
|
| 900 |
|
|
|
| 901 |
|
|
return frwl;
|
| 902 |
|
|
}
|
| 903 |
|
|
|
| 904 |
|
|
static int
|
| 905 |
|
|
ip_fw_ctl(int stage, struct mbuf **mm)
|
| 906 |
|
|
{
|
| 907 |
|
|
int error;
|
| 908 |
|
|
struct mbuf *m;
|
| 909 |
|
|
|
| 910 |
|
|
if (stage == IP_FW_GET) {
|
| 911 |
|
|
struct ip_fw_chain *fcp = ip_fw_chain.lh_first;
|
| 912 |
|
|
*mm = m = m_get(M_WAIT, MT_SOOPTS);
|
| 913 |
|
|
for (; fcp; fcp = fcp->chain.le_next) {
|
| 914 |
|
|
memcpy(m->m_data, fcp->rule, sizeof *(fcp->rule));
|
| 915 |
|
|
m->m_len = sizeof *(fcp->rule);
|
| 916 |
|
|
m->m_next = m_get(M_WAIT, MT_SOOPTS);
|
| 917 |
|
|
m = m->m_next;
|
| 918 |
|
|
m->m_len = 0;
|
| 919 |
|
|
}
|
| 920 |
|
|
return (0);
|
| 921 |
|
|
}
|
| 922 |
|
|
m = *mm;
|
| 923 |
|
|
/* only allow get calls if secure mode > 2 */
|
| 924 |
|
|
if (securelevel > 2) {
|
| 925 |
|
|
if (m) (void)m_free(m);
|
| 926 |
|
|
return(EPERM);
|
| 927 |
|
|
}
|
| 928 |
|
|
if (stage == IP_FW_FLUSH) {
|
| 929 |
|
|
while (ip_fw_chain.lh_first != NULL &&
|
| 930 |
|
|
ip_fw_chain.lh_first->rule->fw_number != (u_short)-1) {
|
| 931 |
|
|
struct ip_fw_chain *fcp = ip_fw_chain.lh_first;
|
| 932 |
|
|
int s = splnet();
|
| 933 |
|
|
LIST_REMOVE(ip_fw_chain.lh_first, chain);
|
| 934 |
|
|
splx(s);
|
| 935 |
|
|
free(fcp->rule, M_IPFW);
|
| 936 |
|
|
free(fcp, M_IPFW);
|
| 937 |
|
|
}
|
| 938 |
|
|
if (m) (void)m_free(m);
|
| 939 |
|
|
return (0);
|
| 940 |
|
|
}
|
| 941 |
|
|
if (stage == IP_FW_ZERO) {
|
| 942 |
|
|
error = zero_entry(m);
|
| 943 |
|
|
if (m) (void)m_free(m);
|
| 944 |
|
|
return (error);
|
| 945 |
|
|
}
|
| 946 |
|
|
if (m == NULL) {
|
| 947 |
|
|
printf("%s NULL mbuf ptr\n", err_prefix);
|
| 948 |
|
|
return (EINVAL);
|
| 949 |
|
|
}
|
| 950 |
|
|
|
| 951 |
|
|
if (stage == IP_FW_ADD) {
|
| 952 |
|
|
struct ip_fw *frwl = check_ipfw_mbuf(m);
|
| 953 |
|
|
|
| 954 |
|
|
if (!frwl)
|
| 955 |
|
|
error = EINVAL;
|
| 956 |
|
|
else
|
| 957 |
|
|
error = add_entry(&ip_fw_chain, frwl);
|
| 958 |
|
|
if (m) (void)m_free(m);
|
| 959 |
|
|
return error;
|
| 960 |
|
|
}
|
| 961 |
|
|
if (stage == IP_FW_DEL) {
|
| 962 |
|
|
if (m->m_len != sizeof(struct ip_fw)) {
|
| 963 |
|
|
dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len,
|
| 964 |
|
|
(int)sizeof(struct ip_fw)));
|
| 965 |
|
|
error = EINVAL;
|
| 966 |
|
|
} else if (mtod(m, struct ip_fw *)->fw_number == (u_short)-1) {
|
| 967 |
|
|
dprintf(("%s can't delete rule 65535\n", err_prefix));
|
| 968 |
|
|
error = EINVAL;
|
| 969 |
|
|
} else
|
| 970 |
|
|
error = del_entry(&ip_fw_chain,
|
| 971 |
|
|
mtod(m, struct ip_fw *)->fw_number);
|
| 972 |
|
|
if (m) (void)m_free(m);
|
| 973 |
|
|
return error;
|
| 974 |
|
|
}
|
| 975 |
|
|
|
| 976 |
|
|
dprintf(("%s unknown request %d\n", err_prefix, stage));
|
| 977 |
|
|
if (m) (void)m_free(m);
|
| 978 |
|
|
return (EINVAL);
|
| 979 |
|
|
}
|
| 980 |
|
|
|
| 981 |
|
|
void
|
| 982 |
|
|
ip_fw_init(void)
|
| 983 |
|
|
{
|
| 984 |
|
|
struct ip_fw default_rule;
|
| 985 |
|
|
|
| 986 |
|
|
ip_fw_chk_ptr = ip_fw_chk;
|
| 987 |
|
|
ip_fw_ctl_ptr = ip_fw_ctl;
|
| 988 |
|
|
LIST_INIT(&ip_fw_chain);
|
| 989 |
|
|
|
| 990 |
|
|
bzero(&default_rule, sizeof default_rule);
|
| 991 |
|
|
default_rule.fw_prot = IPPROTO_IP;
|
| 992 |
|
|
default_rule.fw_number = (u_short)-1;
|
| 993 |
|
|
#ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
|
| 994 |
|
|
default_rule.fw_flg |= IP_FW_F_ACCEPT;
|
| 995 |
|
|
#else
|
| 996 |
|
|
default_rule.fw_flg |= IP_FW_F_DENY;
|
| 997 |
|
|
#endif
|
| 998 |
|
|
default_rule.fw_flg |= IP_FW_F_IN | IP_FW_F_OUT;
|
| 999 |
|
|
if (check_ipfw_struct(&default_rule) == NULL ||
|
| 1000 |
|
|
add_entry(&ip_fw_chain, &default_rule))
|
| 1001 |
|
|
panic(__FUNCTION__);
|
| 1002 |
|
|
|
| 1003 |
|
|
printf("IP packet filtering initialized, "
|
| 1004 |
|
|
#ifdef IPDIVERT
|
| 1005 |
|
|
"divert enabled, ");
|
| 1006 |
|
|
#else
|
| 1007 |
|
|
"divert disabled, ");
|
| 1008 |
|
|
#endif
|
| 1009 |
|
|
#ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
|
| 1010 |
|
|
printf("default to accept, ");
|
| 1011 |
|
|
#endif
|
| 1012 |
|
|
#ifndef IPFIREWALL_VERBOSE
|
| 1013 |
|
|
printf("logging disabled\n");
|
| 1014 |
|
|
#else
|
| 1015 |
|
|
if (fw_verbose_limit == 0)
|
| 1016 |
|
|
printf("unlimited logging\n");
|
| 1017 |
|
|
else
|
| 1018 |
|
|
printf("logging limited to %d packets/entry\n",
|
| 1019 |
|
|
fw_verbose_limit);
|
| 1020 |
|
|
#endif
|
| 1021 |
|
|
}
|
| 1022 |
|
|
|
| 1023 |
|
|
#ifdef IPFIREWALL_MODULE
|
| 1024 |
|
|
|
| 1025 |
|
|
#include <sys/exec.h>
|
| 1026 |
|
|
#include <sys/sysent.h>
|
| 1027 |
|
|
#include <sys/lkm.h>
|
| 1028 |
|
|
|
| 1029 |
|
|
MOD_MISC(ipfw);
|
| 1030 |
|
|
|
| 1031 |
|
|
static int
|
| 1032 |
|
|
ipfw_load(struct lkm_table *lkmtp, int cmd)
|
| 1033 |
|
|
{
|
| 1034 |
|
|
int s=splnet();
|
| 1035 |
|
|
|
| 1036 |
|
|
old_chk_ptr = ip_fw_chk_ptr;
|
| 1037 |
|
|
old_ctl_ptr = ip_fw_ctl_ptr;
|
| 1038 |
|
|
|
| 1039 |
|
|
ip_fw_init();
|
| 1040 |
|
|
splx(s);
|
| 1041 |
|
|
return 0;
|
| 1042 |
|
|
}
|
| 1043 |
|
|
|
| 1044 |
|
|
static int
|
| 1045 |
|
|
ipfw_unload(struct lkm_table *lkmtp, int cmd)
|
| 1046 |
|
|
{
|
| 1047 |
|
|
int s=splnet();
|
| 1048 |
|
|
|
| 1049 |
|
|
ip_fw_chk_ptr = old_chk_ptr;
|
| 1050 |
|
|
ip_fw_ctl_ptr = old_ctl_ptr;
|
| 1051 |
|
|
|
| 1052 |
|
|
while (ip_fw_chain.lh_first != NULL) {
|
| 1053 |
|
|
struct ip_fw_chain *fcp = ip_fw_chain.lh_first;
|
| 1054 |
|
|
LIST_REMOVE(ip_fw_chain.lh_first, chain);
|
| 1055 |
|
|
free(fcp->rule, M_IPFW);
|
| 1056 |
|
|
free(fcp, M_IPFW);
|
| 1057 |
|
|
}
|
| 1058 |
|
|
|
| 1059 |
|
|
splx(s);
|
| 1060 |
|
|
printf("IP firewall unloaded\n");
|
| 1061 |
|
|
return 0;
|
| 1062 |
|
|
}
|
| 1063 |
|
|
|
| 1064 |
|
|
int
|
| 1065 |
|
|
ipfw_mod(struct lkm_table *lkmtp, int cmd, int ver)
|
| 1066 |
|
|
{
|
| 1067 |
|
|
DISPATCH(lkmtp, cmd, ver, ipfw_load, ipfw_unload, lkm_nullcmd);
|
| 1068 |
|
|
}
|
| 1069 |
|
|
#endif
|
