[39e6e65a] | 1 | /* |
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| 2 | * Copyright (c) 1996 Alex Nash |
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| 3 | * Copyright (c) 1993 Daniel Boulet |
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| 4 | * Copyright (c) 1994 Ugen J.S.Antsilevich |
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| 5 | * |
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| 6 | * Redistribution and use in source forms, with and without modification, |
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| 7 | * are permitted provided that this entire comment appears intact. |
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| 8 | * |
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| 9 | * Redistribution in binary form may occur without any restrictions. |
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| 10 | * Obviously, it would be nice if you gave credit where credit is due |
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| 11 | * but requiring it would be too onerous. |
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| 12 | * |
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| 13 | * This software is provided ``AS IS'' without any warranties of any kind. |
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| 14 | * |
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| 15 | * $Id$ |
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| 16 | */ |
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| 17 | |
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| 18 | /* |
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| 19 | * Implement IP packet firewall |
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| 20 | */ |
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| 21 | |
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| 22 | #ifndef IPFIREWALL_MODULE |
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| 23 | #include "opt_ipfw.h" |
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| 24 | #endif |
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| 25 | |
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| 26 | #include <sys/param.h> |
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| 27 | #include <sys/systm.h> |
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| 28 | #include <sys/malloc.h> |
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| 29 | #include <sys/mbuf.h> |
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| 30 | #include <sys/queue.h> |
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| 31 | #include <sys/kernel.h> |
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| 32 | #include <sys/socket.h> |
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| 33 | #include <sys/time.h> |
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| 34 | #include <sys/sysctl.h> |
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| 35 | #include <net/if.h> |
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| 36 | #include <net/route.h> |
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| 37 | #include <netinet/in.h> |
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| 38 | #include <netinet/in_systm.h> |
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| 39 | #include <netinet/ip.h> |
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| 40 | #include <netinet/ip_var.h> |
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| 41 | #include <netinet/ip_icmp.h> |
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| 42 | #include <netinet/ip_fw.h> |
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| 43 | #include <netinet/tcp.h> |
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| 44 | #include <netinet/tcp_timer.h> |
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| 45 | #include <netinet/tcp_var.h> |
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| 46 | #include <netinet/tcpip.h> |
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| 47 | #include <netinet/udp.h> |
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| 48 | |
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| 49 | static int fw_debug = 1; |
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| 50 | #ifdef IPFIREWALL_VERBOSE |
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| 51 | static int fw_verbose = 1; |
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| 52 | #else |
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| 53 | static int fw_verbose = 0; |
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| 54 | #endif |
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| 55 | #ifdef IPFIREWALL_VERBOSE_LIMIT |
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| 56 | static int fw_verbose_limit = IPFIREWALL_VERBOSE_LIMIT; |
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| 57 | #else |
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| 58 | static int fw_verbose_limit = 0; |
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| 59 | #endif |
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| 60 | |
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| 61 | LIST_HEAD (ip_fw_head, ip_fw_chain) ip_fw_chain; |
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| 62 | |
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[36799d4] | 63 | /* |
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| 64 | * ccj - No current need for firewall so have provided the MIB. |
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| 65 | */ |
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| 66 | #if 0 |
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[39e6e65a] | 67 | #ifdef SYSCTL_NODE |
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| 68 | SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall"); |
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| 69 | SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, debug, CTLFLAG_RW, &fw_debug, 0, ""); |
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| 70 | SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose, CTLFLAG_RW, &fw_verbose, 0, ""); |
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| 71 | SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit, CTLFLAG_RW, &fw_verbose_limit, 0, ""); |
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| 72 | #endif |
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[36799d4] | 73 | #endif |
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[39e6e65a] | 74 | |
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| 75 | #define dprintf(a) if (!fw_debug); else printf a |
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| 76 | |
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| 77 | #define print_ip(a) printf("%ld.%ld.%ld.%ld",(ntohl(a.s_addr)>>24)&0xFF,\ |
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| 78 | (ntohl(a.s_addr)>>16)&0xFF,\ |
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| 79 | (ntohl(a.s_addr)>>8)&0xFF,\ |
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| 80 | (ntohl(a.s_addr))&0xFF); |
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| 81 | |
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| 82 | #define dprint_ip(a) if (!fw_debug); else print_ip(a) |
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| 83 | |
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| 84 | static int add_entry __P((struct ip_fw_head *chainptr, struct ip_fw *frwl)); |
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| 85 | static int del_entry __P((struct ip_fw_head *chainptr, u_short number)); |
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| 86 | static int zero_entry __P((struct mbuf *m)); |
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| 87 | static struct ip_fw *check_ipfw_struct __P((struct ip_fw *m)); |
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| 88 | static struct ip_fw *check_ipfw_mbuf __P((struct mbuf *fw)); |
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| 89 | static int ipopts_match __P((struct ip *ip, struct ip_fw *f)); |
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| 90 | static int port_match __P((u_short *portptr, int nports, u_short port, |
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| 91 | int range_flag)); |
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| 92 | static int tcpflg_match __P((struct tcphdr *tcp, struct ip_fw *f)); |
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| 93 | static int icmptype_match __P((struct icmp * icmp, struct ip_fw * f)); |
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| 94 | static void ipfw_report __P((struct ip_fw *f, struct ip *ip, |
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| 95 | struct ifnet *rif, struct ifnet *oif)); |
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| 96 | |
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| 97 | #ifdef IPFIREWALL_MODULE |
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| 98 | static ip_fw_chk_t *old_chk_ptr; |
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| 99 | static ip_fw_ctl_t *old_ctl_ptr; |
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| 100 | #endif |
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| 101 | |
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| 102 | static int ip_fw_chk __P((struct ip **pip, int hlen, |
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| 103 | struct ifnet *oif, int ignport, struct mbuf **m)); |
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| 104 | static int ip_fw_ctl __P((int stage, struct mbuf **mm)); |
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| 105 | |
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| 106 | static char err_prefix[] = "ip_fw_ctl:"; |
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| 107 | |
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| 108 | /* |
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| 109 | * Returns 1 if the port is matched by the vector, 0 otherwise |
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| 110 | */ |
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| 111 | static inline int |
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| 112 | port_match(u_short *portptr, int nports, u_short port, int range_flag) |
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| 113 | { |
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| 114 | if (!nports) |
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| 115 | return 1; |
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| 116 | if (range_flag) { |
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| 117 | if (portptr[0] <= port && port <= portptr[1]) { |
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| 118 | return 1; |
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| 119 | } |
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| 120 | nports -= 2; |
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| 121 | portptr += 2; |
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| 122 | } |
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| 123 | while (nports-- > 0) { |
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| 124 | if (*portptr++ == port) { |
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| 125 | return 1; |
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| 126 | } |
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| 127 | } |
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| 128 | return 0; |
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| 129 | } |
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| 130 | |
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| 131 | static int |
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| 132 | tcpflg_match(struct tcphdr *tcp, struct ip_fw *f) |
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| 133 | { |
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| 134 | u_char flg_set, flg_clr; |
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| 135 | |
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| 136 | if ((f->fw_tcpf & IP_FW_TCPF_ESTAB) && |
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| 137 | (tcp->th_flags & (IP_FW_TCPF_RST | IP_FW_TCPF_ACK))) |
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| 138 | return 1; |
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| 139 | |
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| 140 | flg_set = tcp->th_flags & f->fw_tcpf; |
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| 141 | flg_clr = tcp->th_flags & f->fw_tcpnf; |
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| 142 | |
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| 143 | if (flg_set != f->fw_tcpf) |
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| 144 | return 0; |
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| 145 | if (flg_clr) |
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| 146 | return 0; |
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| 147 | |
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| 148 | return 1; |
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| 149 | } |
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| 150 | |
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| 151 | static int |
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| 152 | icmptype_match(struct icmp *icmp, struct ip_fw *f) |
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| 153 | { |
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| 154 | int type; |
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| 155 | |
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| 156 | if (!(f->fw_flg & IP_FW_F_ICMPBIT)) |
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| 157 | return(1); |
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| 158 | |
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| 159 | type = icmp->icmp_type; |
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| 160 | |
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| 161 | /* check for matching type in the bitmap */ |
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| 162 | if (type < IP_FW_ICMPTYPES_DIM * sizeof(unsigned) * 8 && |
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| 163 | (f->fw_icmptypes[type / (sizeof(unsigned) * 8)] & |
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| 164 | (1U << (type % (8 * sizeof(unsigned)))))) |
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| 165 | return(1); |
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| 166 | |
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| 167 | return(0); /* no match */ |
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| 168 | } |
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| 169 | |
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| 170 | static int |
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| 171 | ipopts_match(struct ip *ip, struct ip_fw *f) |
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| 172 | { |
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| 173 | register u_char *cp; |
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| 174 | int opt, optlen, cnt; |
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| 175 | u_char opts, nopts, nopts_sve; |
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| 176 | |
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| 177 | cp = (u_char *)(ip + 1); |
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| 178 | cnt = (ip->ip_hl << 2) - sizeof (struct ip); |
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| 179 | opts = f->fw_ipopt; |
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| 180 | nopts = nopts_sve = f->fw_ipnopt; |
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| 181 | |
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| 182 | for (; cnt > 0; cnt -= optlen, cp += optlen) { |
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| 183 | opt = cp[IPOPT_OPTVAL]; |
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| 184 | if (opt == IPOPT_EOL) |
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| 185 | break; |
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| 186 | if (opt == IPOPT_NOP) |
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| 187 | optlen = 1; |
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| 188 | else { |
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| 189 | optlen = cp[IPOPT_OLEN]; |
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| 190 | if (optlen <= 0 || optlen > cnt) { |
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| 191 | return 0; /*XXX*/ |
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| 192 | } |
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| 193 | } |
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| 194 | switch (opt) { |
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| 195 | |
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| 196 | default: |
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| 197 | break; |
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| 198 | |
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| 199 | case IPOPT_LSRR: |
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| 200 | opts &= ~IP_FW_IPOPT_LSRR; |
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| 201 | nopts &= ~IP_FW_IPOPT_LSRR; |
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| 202 | break; |
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| 203 | |
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| 204 | case IPOPT_SSRR: |
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| 205 | opts &= ~IP_FW_IPOPT_SSRR; |
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| 206 | nopts &= ~IP_FW_IPOPT_SSRR; |
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| 207 | break; |
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| 208 | |
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| 209 | case IPOPT_RR: |
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| 210 | opts &= ~IP_FW_IPOPT_RR; |
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| 211 | nopts &= ~IP_FW_IPOPT_RR; |
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| 212 | break; |
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| 213 | case IPOPT_TS: |
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| 214 | opts &= ~IP_FW_IPOPT_TS; |
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| 215 | nopts &= ~IP_FW_IPOPT_TS; |
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| 216 | break; |
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| 217 | } |
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| 218 | if (opts == nopts) |
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| 219 | break; |
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| 220 | } |
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| 221 | if (opts == 0 && nopts == nopts_sve) |
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| 222 | return 1; |
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| 223 | else |
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| 224 | return 0; |
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| 225 | } |
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| 226 | |
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| 227 | static inline int |
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| 228 | iface_match(struct ifnet *ifp, union ip_fw_if *ifu, int byname) |
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| 229 | { |
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| 230 | /* Check by name or by IP address */ |
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| 231 | if (byname) { |
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| 232 | /* Check unit number (-1 is wildcard) */ |
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| 233 | if (ifu->fu_via_if.unit != -1 |
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| 234 | && ifp->if_unit != ifu->fu_via_if.unit) |
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| 235 | return(0); |
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| 236 | /* Check name */ |
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| 237 | if (strncmp(ifp->if_name, ifu->fu_via_if.name, FW_IFNLEN)) |
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| 238 | return(0); |
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| 239 | return(1); |
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| 240 | } else if (ifu->fu_via_ip.s_addr != 0) { /* Zero == wildcard */ |
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| 241 | struct ifaddr *ia; |
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| 242 | |
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| 243 | for (ia = ifp->if_addrlist; ia; ia = ia->ifa_next) { |
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| 244 | if (ia->ifa_addr == NULL) |
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| 245 | continue; |
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| 246 | if (ia->ifa_addr->sa_family != AF_INET) |
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| 247 | continue; |
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| 248 | if (ifu->fu_via_ip.s_addr != ((struct sockaddr_in *) |
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| 249 | (ia->ifa_addr))->sin_addr.s_addr) |
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| 250 | continue; |
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| 251 | return(1); |
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| 252 | } |
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| 253 | return(0); |
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| 254 | } |
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| 255 | return(1); |
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| 256 | } |
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| 257 | |
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| 258 | static void |
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| 259 | ipfw_report(struct ip_fw *f, struct ip *ip, |
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| 260 | struct ifnet *rif, struct ifnet *oif) |
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| 261 | { |
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| 262 | static int counter; |
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| 263 | struct tcphdr *const tcp = (struct tcphdr *) ((u_long *) ip+ ip->ip_hl); |
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| 264 | struct udphdr *const udp = (struct udphdr *) ((u_long *) ip+ ip->ip_hl); |
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| 265 | struct icmp *const icmp = (struct icmp *) ((u_long *) ip + ip->ip_hl); |
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| 266 | int count; |
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| 267 | |
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| 268 | count = f ? f->fw_pcnt : ++counter; |
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| 269 | if (fw_verbose_limit != 0 && count > fw_verbose_limit) |
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| 270 | return; |
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| 271 | |
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| 272 | /* Print command name */ |
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| 273 | printf("ipfw: %d ", f ? f->fw_number : -1); |
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| 274 | if (!f) |
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| 275 | printf("Refuse"); |
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| 276 | else |
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| 277 | switch (f->fw_flg & IP_FW_F_COMMAND) { |
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| 278 | case IP_FW_F_DENY: |
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| 279 | printf("Deny"); |
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| 280 | break; |
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| 281 | case IP_FW_F_REJECT: |
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| 282 | if (f->fw_reject_code == IP_FW_REJECT_RST) |
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| 283 | printf("Reset"); |
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| 284 | else |
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| 285 | printf("Unreach"); |
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| 286 | break; |
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| 287 | case IP_FW_F_ACCEPT: |
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| 288 | printf("Accept"); |
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| 289 | break; |
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| 290 | case IP_FW_F_COUNT: |
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| 291 | printf("Count"); |
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| 292 | break; |
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| 293 | case IP_FW_F_DIVERT: |
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| 294 | printf("Divert %d", f->fw_divert_port); |
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| 295 | break; |
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| 296 | case IP_FW_F_TEE: |
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| 297 | printf("Tee %d", f->fw_divert_port); |
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| 298 | break; |
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| 299 | case IP_FW_F_SKIPTO: |
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| 300 | printf("SkipTo %d", f->fw_skipto_rule); |
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| 301 | break; |
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| 302 | default: |
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| 303 | printf("UNKNOWN"); |
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| 304 | break; |
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| 305 | } |
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| 306 | printf(" "); |
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| 307 | |
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| 308 | switch (ip->ip_p) { |
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| 309 | case IPPROTO_TCP: |
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| 310 | printf("TCP "); |
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| 311 | print_ip(ip->ip_src); |
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| 312 | if ((ip->ip_off & IP_OFFMASK) == 0) |
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| 313 | printf(":%d ", ntohs(tcp->th_sport)); |
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| 314 | else |
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| 315 | printf(" "); |
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| 316 | print_ip(ip->ip_dst); |
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| 317 | if ((ip->ip_off & IP_OFFMASK) == 0) |
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| 318 | printf(":%d", ntohs(tcp->th_dport)); |
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| 319 | break; |
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| 320 | case IPPROTO_UDP: |
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| 321 | printf("UDP "); |
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| 322 | print_ip(ip->ip_src); |
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| 323 | if ((ip->ip_off & IP_OFFMASK) == 0) |
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| 324 | printf(":%d ", ntohs(udp->uh_sport)); |
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| 325 | else |
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| 326 | printf(" "); |
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| 327 | print_ip(ip->ip_dst); |
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| 328 | if ((ip->ip_off & IP_OFFMASK) == 0) |
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| 329 | printf(":%d", ntohs(udp->uh_dport)); |
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| 330 | break; |
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| 331 | case IPPROTO_ICMP: |
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| 332 | printf("ICMP:%u.%u ", icmp->icmp_type, icmp->icmp_code); |
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| 333 | print_ip(ip->ip_src); |
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| 334 | printf(" "); |
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| 335 | print_ip(ip->ip_dst); |
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| 336 | break; |
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| 337 | default: |
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| 338 | printf("P:%d ", ip->ip_p); |
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| 339 | print_ip(ip->ip_src); |
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| 340 | printf(" "); |
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| 341 | print_ip(ip->ip_dst); |
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| 342 | break; |
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| 343 | } |
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| 344 | if (oif) |
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| 345 | printf(" out via %s%d", oif->if_name, oif->if_unit); |
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| 346 | else if (rif) |
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| 347 | printf(" in via %s%d", rif->if_name, rif->if_unit); |
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| 348 | if ((ip->ip_off & IP_OFFMASK)) |
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| 349 | printf(" Fragment = %d",ip->ip_off & IP_OFFMASK); |
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| 350 | printf("\n"); |
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| 351 | if (fw_verbose_limit != 0 && count == fw_verbose_limit) |
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| 352 | printf("ipfw: limit reached on rule #%d\n", |
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| 353 | f ? f->fw_number : -1); |
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| 354 | } |
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| 355 | |
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| 356 | /* |
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| 357 | * Parameters: |
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| 358 | * |
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| 359 | * ip Pointer to packet header (struct ip *) |
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| 360 | * hlen Packet header length |
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| 361 | * oif Outgoing interface, or NULL if packet is incoming |
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| 362 | * ignport Ignore all divert/tee rules to this port (if non-zero) |
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| 363 | * *m The packet; we set to NULL when/if we nuke it. |
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| 364 | * |
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| 365 | * Return value: |
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| 366 | * |
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| 367 | * 0 The packet is to be accepted and routed normally OR |
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| 368 | * the packet was denied/rejected and has been dropped; |
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| 369 | * in the latter case, *m is equal to NULL upon return. |
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| 370 | * port Divert the packet to port. |
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| 371 | */ |
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| 372 | |
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| 373 | static int |
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| 374 | ip_fw_chk(struct ip **pip, int hlen, |
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| 375 | struct ifnet *oif, int ignport, struct mbuf **m) |
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| 376 | { |
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| 377 | struct ip_fw_chain *chain; |
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| 378 | struct ip_fw *rule = NULL; |
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| 379 | struct ip *ip = *pip; |
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| 380 | struct ifnet *const rif = (*m)->m_pkthdr.rcvif; |
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| 381 | u_short offset = (ip->ip_off & IP_OFFMASK); |
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| 382 | u_short src_port, dst_port; |
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| 383 | |
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| 384 | /* |
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| 385 | * Go down the chain, looking for enlightment |
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| 386 | */ |
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| 387 | for (chain=ip_fw_chain.lh_first; chain; chain = chain->chain.le_next) { |
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| 388 | register struct ip_fw *const f = chain->rule; |
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| 389 | |
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| 390 | /* Check direction inbound */ |
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| 391 | if (!oif && !(f->fw_flg & IP_FW_F_IN)) |
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| 392 | continue; |
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| 393 | |
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| 394 | /* Check direction outbound */ |
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| 395 | if (oif && !(f->fw_flg & IP_FW_F_OUT)) |
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| 396 | continue; |
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| 397 | |
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| 398 | /* Fragments */ |
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| 399 | if ((f->fw_flg & IP_FW_F_FRAG) && !(ip->ip_off & IP_OFFMASK)) |
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| 400 | continue; |
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| 401 | |
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| 402 | /* If src-addr doesn't match, not this rule. */ |
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| 403 | if (((f->fw_flg & IP_FW_F_INVSRC) != 0) ^ ((ip->ip_src.s_addr |
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| 404 | & f->fw_smsk.s_addr) != f->fw_src.s_addr)) |
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| 405 | continue; |
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| 406 | |
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| 407 | /* If dest-addr doesn't match, not this rule. */ |
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| 408 | if (((f->fw_flg & IP_FW_F_INVDST) != 0) ^ ((ip->ip_dst.s_addr |
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| 409 | & f->fw_dmsk.s_addr) != f->fw_dst.s_addr)) |
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| 410 | continue; |
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| 411 | |
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| 412 | /* Interface check */ |
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| 413 | if ((f->fw_flg & IF_FW_F_VIAHACK) == IF_FW_F_VIAHACK) { |
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| 414 | struct ifnet *const iface = oif ? oif : rif; |
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| 415 | |
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| 416 | /* Backwards compatibility hack for "via" */ |
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| 417 | if (!iface || !iface_match(iface, |
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| 418 | &f->fw_in_if, f->fw_flg & IP_FW_F_OIFNAME)) |
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| 419 | continue; |
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| 420 | } else { |
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| 421 | /* Check receive interface */ |
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| 422 | if ((f->fw_flg & IP_FW_F_IIFACE) |
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| 423 | && (!rif || !iface_match(rif, |
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| 424 | &f->fw_in_if, f->fw_flg & IP_FW_F_IIFNAME))) |
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| 425 | continue; |
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| 426 | /* Check outgoing interface */ |
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| 427 | if ((f->fw_flg & IP_FW_F_OIFACE) |
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| 428 | && (!oif || !iface_match(oif, |
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| 429 | &f->fw_out_if, f->fw_flg & IP_FW_F_OIFNAME))) |
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| 430 | continue; |
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| 431 | } |
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| 432 | |
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| 433 | /* Check IP options */ |
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| 434 | if (f->fw_ipopt != f->fw_ipnopt && !ipopts_match(ip, f)) |
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| 435 | continue; |
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| 436 | |
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| 437 | /* Check protocol; if wildcard, match */ |
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| 438 | if (f->fw_prot == IPPROTO_IP) |
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| 439 | goto got_match; |
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| 440 | |
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| 441 | /* If different, don't match */ |
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| 442 | if (ip->ip_p != f->fw_prot) |
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| 443 | continue; |
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| 444 | |
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| 445 | #define PULLUP_TO(len) do { \ |
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| 446 | if ((*m)->m_len < (len) \ |
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| 447 | && (*m = m_pullup(*m, (len))) == 0) { \ |
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| 448 | goto bogusfrag; \ |
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| 449 | } \ |
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| 450 | *pip = ip = mtod(*m, struct ip *); \ |
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| 451 | offset = (ip->ip_off & IP_OFFMASK); \ |
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| 452 | } while (0) |
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| 453 | |
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| 454 | /* Protocol specific checks */ |
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| 455 | switch (ip->ip_p) { |
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| 456 | case IPPROTO_TCP: |
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| 457 | { |
---|
| 458 | struct tcphdr *tcp; |
---|
| 459 | |
---|
| 460 | if (offset == 1) /* cf. RFC 1858 */ |
---|
| 461 | goto bogusfrag; |
---|
| 462 | if (offset != 0) { |
---|
| 463 | /* |
---|
| 464 | * TCP flags and ports aren't available in this |
---|
| 465 | * packet -- if this rule specified either one, |
---|
| 466 | * we consider the rule a non-match. |
---|
| 467 | */ |
---|
| 468 | if (f->fw_nports != 0 || |
---|
| 469 | f->fw_tcpf != f->fw_tcpnf) |
---|
| 470 | continue; |
---|
| 471 | |
---|
| 472 | break; |
---|
| 473 | } |
---|
| 474 | PULLUP_TO(hlen + 14); |
---|
| 475 | tcp = (struct tcphdr *) ((u_long *)ip + ip->ip_hl); |
---|
| 476 | if (f->fw_tcpf != f->fw_tcpnf && !tcpflg_match(tcp, f)) |
---|
| 477 | continue; |
---|
| 478 | src_port = ntohs(tcp->th_sport); |
---|
| 479 | dst_port = ntohs(tcp->th_dport); |
---|
| 480 | goto check_ports; |
---|
| 481 | } |
---|
| 482 | |
---|
| 483 | case IPPROTO_UDP: |
---|
| 484 | { |
---|
| 485 | struct udphdr *udp; |
---|
| 486 | |
---|
| 487 | if (offset != 0) { |
---|
| 488 | /* |
---|
| 489 | * Port specification is unavailable -- if this |
---|
| 490 | * rule specifies a port, we consider the rule |
---|
| 491 | * a non-match. |
---|
| 492 | */ |
---|
| 493 | if (f->fw_nports != 0) |
---|
| 494 | continue; |
---|
| 495 | |
---|
| 496 | break; |
---|
| 497 | } |
---|
| 498 | PULLUP_TO(hlen + 4); |
---|
| 499 | udp = (struct udphdr *) ((u_long *)ip + ip->ip_hl); |
---|
| 500 | src_port = ntohs(udp->uh_sport); |
---|
| 501 | dst_port = ntohs(udp->uh_dport); |
---|
| 502 | check_ports: |
---|
| 503 | if (!port_match(&f->fw_pts[0], |
---|
| 504 | IP_FW_GETNSRCP(f), src_port, |
---|
| 505 | f->fw_flg & IP_FW_F_SRNG)) |
---|
| 506 | continue; |
---|
| 507 | if (!port_match(&f->fw_pts[IP_FW_GETNSRCP(f)], |
---|
| 508 | IP_FW_GETNDSTP(f), dst_port, |
---|
| 509 | f->fw_flg & IP_FW_F_DRNG)) |
---|
| 510 | continue; |
---|
| 511 | break; |
---|
| 512 | } |
---|
| 513 | |
---|
| 514 | case IPPROTO_ICMP: |
---|
| 515 | { |
---|
| 516 | struct icmp *icmp; |
---|
| 517 | |
---|
| 518 | if (offset != 0) /* Type isn't valid */ |
---|
| 519 | break; |
---|
| 520 | PULLUP_TO(hlen + 2); |
---|
| 521 | icmp = (struct icmp *) ((u_long *)ip + ip->ip_hl); |
---|
| 522 | if (!icmptype_match(icmp, f)) |
---|
| 523 | continue; |
---|
| 524 | break; |
---|
| 525 | } |
---|
| 526 | #undef PULLUP_TO |
---|
| 527 | |
---|
| 528 | bogusfrag: |
---|
| 529 | if (fw_verbose) |
---|
| 530 | ipfw_report(NULL, ip, rif, oif); |
---|
| 531 | goto dropit; |
---|
| 532 | } |
---|
| 533 | |
---|
| 534 | got_match: |
---|
| 535 | /* Ignore divert/tee rule if socket port is "ignport" */ |
---|
| 536 | switch (f->fw_flg & IP_FW_F_COMMAND) { |
---|
| 537 | case IP_FW_F_DIVERT: |
---|
| 538 | case IP_FW_F_TEE: |
---|
| 539 | if (f->fw_divert_port == ignport) |
---|
| 540 | continue; /* ignore this rule */ |
---|
| 541 | break; |
---|
| 542 | } |
---|
| 543 | |
---|
| 544 | /* Update statistics */ |
---|
| 545 | f->fw_pcnt += 1; |
---|
| 546 | f->fw_bcnt += ip->ip_len; |
---|
| 547 | f->timestamp = rtems_bsdnet_seconds_since_boot(); |
---|
| 548 | |
---|
| 549 | /* Log to console if desired */ |
---|
| 550 | if ((f->fw_flg & IP_FW_F_PRN) && fw_verbose) |
---|
| 551 | ipfw_report(f, ip, rif, oif); |
---|
| 552 | |
---|
| 553 | /* Take appropriate action */ |
---|
| 554 | switch (f->fw_flg & IP_FW_F_COMMAND) { |
---|
| 555 | case IP_FW_F_ACCEPT: |
---|
| 556 | return(0); |
---|
| 557 | case IP_FW_F_COUNT: |
---|
| 558 | continue; |
---|
| 559 | case IP_FW_F_DIVERT: |
---|
| 560 | return(f->fw_divert_port); |
---|
| 561 | case IP_FW_F_TEE: |
---|
| 562 | /* |
---|
| 563 | * XXX someday tee packet here, but beware that you |
---|
| 564 | * can't use m_copym() or m_copypacket() because |
---|
| 565 | * the divert input routine modifies the mbuf |
---|
| 566 | * (and these routines only increment reference |
---|
| 567 | * counts in the case of mbuf clusters), so need |
---|
| 568 | * to write custom routine. |
---|
| 569 | */ |
---|
| 570 | continue; |
---|
| 571 | case IP_FW_F_SKIPTO: |
---|
| 572 | #ifdef DIAGNOSTIC |
---|
| 573 | while (chain->chain.le_next |
---|
| 574 | && chain->chain.le_next->rule->fw_number |
---|
| 575 | < f->fw_skipto_rule) |
---|
| 576 | #else |
---|
| 577 | while (chain->chain.le_next->rule->fw_number |
---|
| 578 | < f->fw_skipto_rule) |
---|
| 579 | #endif |
---|
| 580 | chain = chain->chain.le_next; |
---|
| 581 | continue; |
---|
| 582 | } |
---|
| 583 | |
---|
| 584 | /* Deny/reject this packet using this rule */ |
---|
| 585 | rule = f; |
---|
| 586 | break; |
---|
| 587 | } |
---|
| 588 | |
---|
| 589 | #ifdef DIAGNOSTIC |
---|
| 590 | /* Rule 65535 should always be there and should always match */ |
---|
| 591 | if (!chain) |
---|
| 592 | panic("ip_fw: chain"); |
---|
| 593 | #endif |
---|
| 594 | |
---|
| 595 | /* |
---|
| 596 | * At this point, we're going to drop the packet. |
---|
| 597 | * Send a reject notice if all of the following are true: |
---|
| 598 | * |
---|
| 599 | * - The packet matched a reject rule |
---|
| 600 | * - The packet is not an ICMP packet |
---|
| 601 | * - The packet is not a multicast or broadcast packet |
---|
| 602 | */ |
---|
| 603 | if ((rule->fw_flg & IP_FW_F_COMMAND) == IP_FW_F_REJECT |
---|
| 604 | && ip->ip_p != IPPROTO_ICMP |
---|
| 605 | && !((*m)->m_flags & (M_BCAST|M_MCAST)) |
---|
| 606 | && !IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { |
---|
| 607 | switch (rule->fw_reject_code) { |
---|
| 608 | case IP_FW_REJECT_RST: |
---|
| 609 | { |
---|
| 610 | struct tcphdr *const tcp = |
---|
| 611 | (struct tcphdr *) ((u_long *)ip + ip->ip_hl); |
---|
| 612 | struct tcpiphdr ti, *const tip = (struct tcpiphdr *) ip; |
---|
| 613 | |
---|
| 614 | if (offset != 0 || (tcp->th_flags & TH_RST)) |
---|
| 615 | break; |
---|
| 616 | ti.ti_i = *((struct ipovly *) ip); |
---|
| 617 | ti.ti_t = *tcp; |
---|
| 618 | bcopy(&ti, ip, sizeof(ti)); |
---|
| 619 | NTOHL(tip->ti_seq); |
---|
| 620 | NTOHL(tip->ti_ack); |
---|
| 621 | tip->ti_len = ip->ip_len - hlen - (tip->ti_off << 2); |
---|
| 622 | if (tcp->th_flags & TH_ACK) { |
---|
| 623 | tcp_respond(NULL, tip, *m, |
---|
| 624 | (tcp_seq)0, ntohl(tcp->th_ack), TH_RST); |
---|
| 625 | } else { |
---|
| 626 | if (tcp->th_flags & TH_SYN) |
---|
| 627 | tip->ti_len++; |
---|
| 628 | tcp_respond(NULL, tip, *m, tip->ti_seq |
---|
| 629 | + tip->ti_len, (tcp_seq)0, TH_RST|TH_ACK); |
---|
| 630 | } |
---|
| 631 | *m = NULL; |
---|
| 632 | break; |
---|
| 633 | } |
---|
| 634 | default: /* Send an ICMP unreachable using code */ |
---|
| 635 | icmp_error(*m, ICMP_UNREACH, |
---|
| 636 | rule->fw_reject_code, 0L, 0); |
---|
| 637 | *m = NULL; |
---|
| 638 | break; |
---|
| 639 | } |
---|
| 640 | } |
---|
| 641 | |
---|
| 642 | dropit: |
---|
| 643 | /* |
---|
| 644 | * Finally, drop the packet. |
---|
| 645 | */ |
---|
| 646 | if (*m) { |
---|
| 647 | m_freem(*m); |
---|
| 648 | *m = NULL; |
---|
| 649 | } |
---|
| 650 | return(0); |
---|
| 651 | } |
---|
| 652 | |
---|
| 653 | static int |
---|
| 654 | add_entry(struct ip_fw_head *chainptr, struct ip_fw *frwl) |
---|
| 655 | { |
---|
| 656 | struct ip_fw *ftmp = 0; |
---|
| 657 | struct ip_fw_chain *fwc = 0, *fcp, *fcpl = 0; |
---|
| 658 | u_short nbr = 0; |
---|
| 659 | int s; |
---|
| 660 | |
---|
| 661 | fwc = malloc(sizeof *fwc, M_IPFW, M_DONTWAIT); |
---|
| 662 | ftmp = malloc(sizeof *ftmp, M_IPFW, M_DONTWAIT); |
---|
| 663 | if (!fwc || !ftmp) { |
---|
| 664 | dprintf(("%s malloc said no\n", err_prefix)); |
---|
| 665 | if (fwc) free(fwc, M_IPFW); |
---|
| 666 | if (ftmp) free(ftmp, M_IPFW); |
---|
| 667 | return (ENOSPC); |
---|
| 668 | } |
---|
| 669 | |
---|
| 670 | bcopy(frwl, ftmp, sizeof(struct ip_fw)); |
---|
| 671 | ftmp->fw_in_if.fu_via_if.name[FW_IFNLEN - 1] = '\0'; |
---|
| 672 | ftmp->fw_pcnt = 0L; |
---|
| 673 | ftmp->fw_bcnt = 0L; |
---|
| 674 | fwc->rule = ftmp; |
---|
| 675 | |
---|
| 676 | s = splnet(); |
---|
| 677 | |
---|
| 678 | if (!chainptr->lh_first) { |
---|
| 679 | LIST_INSERT_HEAD(chainptr, fwc, chain); |
---|
| 680 | splx(s); |
---|
| 681 | return(0); |
---|
| 682 | } else if (ftmp->fw_number == (u_short)-1) { |
---|
| 683 | if (fwc) free(fwc, M_IPFW); |
---|
| 684 | if (ftmp) free(ftmp, M_IPFW); |
---|
| 685 | splx(s); |
---|
| 686 | dprintf(("%s bad rule number\n", err_prefix)); |
---|
| 687 | return (EINVAL); |
---|
| 688 | } |
---|
| 689 | |
---|
| 690 | /* If entry number is 0, find highest numbered rule and add 100 */ |
---|
| 691 | if (ftmp->fw_number == 0) { |
---|
| 692 | for (fcp = chainptr->lh_first; fcp; fcp = fcp->chain.le_next) { |
---|
| 693 | if (fcp->rule->fw_number != (u_short)-1) |
---|
| 694 | nbr = fcp->rule->fw_number; |
---|
| 695 | else |
---|
| 696 | break; |
---|
| 697 | } |
---|
| 698 | if (nbr < (u_short)-1 - 100) |
---|
| 699 | nbr += 100; |
---|
| 700 | ftmp->fw_number = nbr; |
---|
| 701 | } |
---|
| 702 | |
---|
| 703 | /* Got a valid number; now insert it, keeping the list ordered */ |
---|
| 704 | for (fcp = chainptr->lh_first; fcp; fcp = fcp->chain.le_next) { |
---|
| 705 | if (fcp->rule->fw_number > ftmp->fw_number) { |
---|
| 706 | if (fcpl) { |
---|
| 707 | LIST_INSERT_AFTER(fcpl, fwc, chain); |
---|
| 708 | } else { |
---|
| 709 | LIST_INSERT_HEAD(chainptr, fwc, chain); |
---|
| 710 | } |
---|
| 711 | break; |
---|
| 712 | } else { |
---|
| 713 | fcpl = fcp; |
---|
| 714 | } |
---|
| 715 | } |
---|
| 716 | |
---|
| 717 | splx(s); |
---|
| 718 | return (0); |
---|
| 719 | } |
---|
| 720 | |
---|
| 721 | static int |
---|
| 722 | del_entry(struct ip_fw_head *chainptr, u_short number) |
---|
| 723 | { |
---|
| 724 | struct ip_fw_chain *fcp; |
---|
| 725 | int s; |
---|
| 726 | |
---|
| 727 | s = splnet(); |
---|
| 728 | |
---|
| 729 | fcp = chainptr->lh_first; |
---|
| 730 | if (number != (u_short)-1) { |
---|
| 731 | for (; fcp; fcp = fcp->chain.le_next) { |
---|
| 732 | if (fcp->rule->fw_number == number) { |
---|
| 733 | LIST_REMOVE(fcp, chain); |
---|
| 734 | splx(s); |
---|
| 735 | free(fcp->rule, M_IPFW); |
---|
| 736 | free(fcp, M_IPFW); |
---|
| 737 | return 0; |
---|
| 738 | } |
---|
| 739 | } |
---|
| 740 | } |
---|
| 741 | |
---|
| 742 | splx(s); |
---|
| 743 | return (EINVAL); |
---|
| 744 | } |
---|
| 745 | |
---|
| 746 | static int |
---|
| 747 | zero_entry(struct mbuf *m) |
---|
| 748 | { |
---|
| 749 | struct ip_fw *frwl; |
---|
| 750 | struct ip_fw_chain *fcp; |
---|
| 751 | int s; |
---|
| 752 | |
---|
| 753 | if (m) { |
---|
| 754 | if (m->m_len != sizeof(struct ip_fw)) |
---|
| 755 | return(EINVAL); |
---|
| 756 | frwl = mtod(m, struct ip_fw *); |
---|
| 757 | } |
---|
| 758 | else |
---|
| 759 | frwl = NULL; |
---|
| 760 | |
---|
| 761 | /* |
---|
| 762 | * It's possible to insert multiple chain entries with the |
---|
| 763 | * same number, so we don't stop after finding the first |
---|
| 764 | * match if zeroing a specific entry. |
---|
| 765 | */ |
---|
| 766 | s = splnet(); |
---|
| 767 | for (fcp = ip_fw_chain.lh_first; fcp; fcp = fcp->chain.le_next) |
---|
| 768 | if (!frwl || frwl->fw_number == fcp->rule->fw_number) { |
---|
| 769 | fcp->rule->fw_bcnt = fcp->rule->fw_pcnt = 0; |
---|
| 770 | fcp->rule->timestamp = 0; |
---|
| 771 | } |
---|
| 772 | splx(s); |
---|
| 773 | |
---|
| 774 | if (fw_verbose) { |
---|
| 775 | if (frwl) |
---|
| 776 | printf("ipfw: Entry %d cleared.\n", frwl->fw_number); |
---|
| 777 | else |
---|
| 778 | printf("ipfw: Accounting cleared.\n"); |
---|
| 779 | } |
---|
| 780 | |
---|
| 781 | return(0); |
---|
| 782 | } |
---|
| 783 | |
---|
| 784 | static struct ip_fw * |
---|
| 785 | check_ipfw_mbuf(struct mbuf *m) |
---|
| 786 | { |
---|
| 787 | /* Check length */ |
---|
| 788 | if (m->m_len != sizeof(struct ip_fw)) { |
---|
| 789 | dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len, |
---|
| 790 | (int)sizeof(struct ip_fw))); |
---|
| 791 | return (NULL); |
---|
| 792 | } |
---|
| 793 | return(check_ipfw_struct(mtod(m, struct ip_fw *))); |
---|
| 794 | } |
---|
| 795 | |
---|
| 796 | static struct ip_fw * |
---|
| 797 | check_ipfw_struct(struct ip_fw *frwl) |
---|
| 798 | { |
---|
| 799 | /* Check for invalid flag bits */ |
---|
| 800 | if ((frwl->fw_flg & ~IP_FW_F_MASK) != 0) { |
---|
| 801 | dprintf(("%s undefined flag bits set (flags=%x)\n", |
---|
| 802 | err_prefix, frwl->fw_flg)); |
---|
| 803 | return (NULL); |
---|
| 804 | } |
---|
| 805 | /* Must apply to incoming or outgoing (or both) */ |
---|
| 806 | if (!(frwl->fw_flg & (IP_FW_F_IN | IP_FW_F_OUT))) { |
---|
| 807 | dprintf(("%s neither in nor out\n", err_prefix)); |
---|
| 808 | return (NULL); |
---|
| 809 | } |
---|
| 810 | /* Empty interface name is no good */ |
---|
| 811 | if (((frwl->fw_flg & IP_FW_F_IIFNAME) |
---|
| 812 | && !*frwl->fw_in_if.fu_via_if.name) |
---|
| 813 | || ((frwl->fw_flg & IP_FW_F_OIFNAME) |
---|
| 814 | && !*frwl->fw_out_if.fu_via_if.name)) { |
---|
| 815 | dprintf(("%s empty interface name\n", err_prefix)); |
---|
| 816 | return (NULL); |
---|
| 817 | } |
---|
| 818 | /* Sanity check interface matching */ |
---|
| 819 | if ((frwl->fw_flg & IF_FW_F_VIAHACK) == IF_FW_F_VIAHACK) { |
---|
| 820 | ; /* allow "via" backwards compatibility */ |
---|
| 821 | } else if ((frwl->fw_flg & IP_FW_F_IN) |
---|
| 822 | && (frwl->fw_flg & IP_FW_F_OIFACE)) { |
---|
| 823 | dprintf(("%s outgoing interface check on incoming\n", |
---|
| 824 | err_prefix)); |
---|
| 825 | return (NULL); |
---|
| 826 | } |
---|
| 827 | /* Sanity check port ranges */ |
---|
| 828 | if ((frwl->fw_flg & IP_FW_F_SRNG) && IP_FW_GETNSRCP(frwl) < 2) { |
---|
| 829 | dprintf(("%s src range set but n_src_p=%d\n", |
---|
| 830 | err_prefix, IP_FW_GETNSRCP(frwl))); |
---|
| 831 | return (NULL); |
---|
| 832 | } |
---|
| 833 | if ((frwl->fw_flg & IP_FW_F_DRNG) && IP_FW_GETNDSTP(frwl) < 2) { |
---|
| 834 | dprintf(("%s dst range set but n_dst_p=%d\n", |
---|
| 835 | err_prefix, IP_FW_GETNDSTP(frwl))); |
---|
| 836 | return (NULL); |
---|
| 837 | } |
---|
| 838 | if (IP_FW_GETNSRCP(frwl) + IP_FW_GETNDSTP(frwl) > IP_FW_MAX_PORTS) { |
---|
| 839 | dprintf(("%s too many ports (%d+%d)\n", |
---|
| 840 | err_prefix, IP_FW_GETNSRCP(frwl), IP_FW_GETNDSTP(frwl))); |
---|
| 841 | return (NULL); |
---|
| 842 | } |
---|
| 843 | /* |
---|
| 844 | * Protocols other than TCP/UDP don't use port range |
---|
| 845 | */ |
---|
| 846 | if ((frwl->fw_prot != IPPROTO_TCP) && |
---|
| 847 | (frwl->fw_prot != IPPROTO_UDP) && |
---|
| 848 | (IP_FW_GETNSRCP(frwl) || IP_FW_GETNDSTP(frwl))) { |
---|
| 849 | dprintf(("%s port(s) specified for non TCP/UDP rule\n", |
---|
| 850 | err_prefix)); |
---|
| 851 | return(NULL); |
---|
| 852 | } |
---|
| 853 | |
---|
| 854 | /* |
---|
| 855 | * Rather than modify the entry to make such entries work, |
---|
| 856 | * we reject this rule and require user level utilities |
---|
| 857 | * to enforce whatever policy they deem appropriate. |
---|
| 858 | */ |
---|
| 859 | if ((frwl->fw_src.s_addr & (~frwl->fw_smsk.s_addr)) || |
---|
| 860 | (frwl->fw_dst.s_addr & (~frwl->fw_dmsk.s_addr))) { |
---|
| 861 | dprintf(("%s rule never matches\n", err_prefix)); |
---|
| 862 | return(NULL); |
---|
| 863 | } |
---|
| 864 | |
---|
| 865 | if ((frwl->fw_flg & IP_FW_F_FRAG) && |
---|
| 866 | (frwl->fw_prot == IPPROTO_UDP || frwl->fw_prot == IPPROTO_TCP)) { |
---|
| 867 | if (frwl->fw_nports) { |
---|
| 868 | dprintf(("%s cannot mix 'frag' and ports\n", err_prefix)); |
---|
| 869 | return(NULL); |
---|
| 870 | } |
---|
| 871 | if (frwl->fw_prot == IPPROTO_TCP && |
---|
| 872 | frwl->fw_tcpf != frwl->fw_tcpnf) { |
---|
| 873 | dprintf(("%s cannot mix 'frag' with TCP flags\n", err_prefix)); |
---|
| 874 | return(NULL); |
---|
| 875 | } |
---|
| 876 | } |
---|
| 877 | |
---|
| 878 | /* Check command specific stuff */ |
---|
| 879 | switch (frwl->fw_flg & IP_FW_F_COMMAND) |
---|
| 880 | { |
---|
| 881 | case IP_FW_F_REJECT: |
---|
| 882 | if (frwl->fw_reject_code >= 0x100 |
---|
| 883 | && !(frwl->fw_prot == IPPROTO_TCP |
---|
| 884 | && frwl->fw_reject_code == IP_FW_REJECT_RST)) { |
---|
| 885 | dprintf(("%s unknown reject code\n", err_prefix)); |
---|
| 886 | return(NULL); |
---|
| 887 | } |
---|
| 888 | break; |
---|
| 889 | case IP_FW_F_DIVERT: /* Diverting to port zero is invalid */ |
---|
| 890 | case IP_FW_F_TEE: |
---|
| 891 | if (frwl->fw_divert_port == 0) { |
---|
| 892 | dprintf(("%s can't divert to port 0\n", err_prefix)); |
---|
| 893 | return (NULL); |
---|
| 894 | } |
---|
| 895 | break; |
---|
| 896 | case IP_FW_F_DENY: |
---|
| 897 | case IP_FW_F_ACCEPT: |
---|
| 898 | case IP_FW_F_COUNT: |
---|
| 899 | case IP_FW_F_SKIPTO: |
---|
| 900 | break; |
---|
| 901 | default: |
---|
| 902 | dprintf(("%s invalid command\n", err_prefix)); |
---|
| 903 | return(NULL); |
---|
| 904 | } |
---|
| 905 | |
---|
| 906 | return frwl; |
---|
| 907 | } |
---|
| 908 | |
---|
| 909 | static int |
---|
| 910 | ip_fw_ctl(int stage, struct mbuf **mm) |
---|
| 911 | { |
---|
| 912 | int error; |
---|
| 913 | struct mbuf *m; |
---|
| 914 | |
---|
| 915 | if (stage == IP_FW_GET) { |
---|
| 916 | struct ip_fw_chain *fcp = ip_fw_chain.lh_first; |
---|
| 917 | *mm = m = m_get(M_WAIT, MT_SOOPTS); |
---|
| 918 | for (; fcp; fcp = fcp->chain.le_next) { |
---|
| 919 | memcpy(m->m_data, fcp->rule, sizeof *(fcp->rule)); |
---|
| 920 | m->m_len = sizeof *(fcp->rule); |
---|
| 921 | m->m_next = m_get(M_WAIT, MT_SOOPTS); |
---|
| 922 | m = m->m_next; |
---|
| 923 | m->m_len = 0; |
---|
| 924 | } |
---|
| 925 | return (0); |
---|
| 926 | } |
---|
| 927 | m = *mm; |
---|
| 928 | /* only allow get calls if secure mode > 2 */ |
---|
| 929 | if (securelevel > 2) { |
---|
| 930 | if (m) (void)m_free(m); |
---|
| 931 | return(EPERM); |
---|
| 932 | } |
---|
| 933 | if (stage == IP_FW_FLUSH) { |
---|
| 934 | while (ip_fw_chain.lh_first != NULL && |
---|
| 935 | ip_fw_chain.lh_first->rule->fw_number != (u_short)-1) { |
---|
| 936 | struct ip_fw_chain *fcp = ip_fw_chain.lh_first; |
---|
| 937 | int s = splnet(); |
---|
| 938 | LIST_REMOVE(ip_fw_chain.lh_first, chain); |
---|
| 939 | splx(s); |
---|
| 940 | free(fcp->rule, M_IPFW); |
---|
| 941 | free(fcp, M_IPFW); |
---|
| 942 | } |
---|
| 943 | if (m) (void)m_free(m); |
---|
| 944 | return (0); |
---|
| 945 | } |
---|
| 946 | if (stage == IP_FW_ZERO) { |
---|
| 947 | error = zero_entry(m); |
---|
| 948 | if (m) (void)m_free(m); |
---|
| 949 | return (error); |
---|
| 950 | } |
---|
| 951 | if (m == NULL) { |
---|
| 952 | printf("%s NULL mbuf ptr\n", err_prefix); |
---|
| 953 | return (EINVAL); |
---|
| 954 | } |
---|
| 955 | |
---|
| 956 | if (stage == IP_FW_ADD) { |
---|
| 957 | struct ip_fw *frwl = check_ipfw_mbuf(m); |
---|
| 958 | |
---|
| 959 | if (!frwl) |
---|
| 960 | error = EINVAL; |
---|
| 961 | else |
---|
| 962 | error = add_entry(&ip_fw_chain, frwl); |
---|
| 963 | if (m) (void)m_free(m); |
---|
| 964 | return error; |
---|
| 965 | } |
---|
| 966 | if (stage == IP_FW_DEL) { |
---|
| 967 | if (m->m_len != sizeof(struct ip_fw)) { |
---|
| 968 | dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len, |
---|
| 969 | (int)sizeof(struct ip_fw))); |
---|
| 970 | error = EINVAL; |
---|
| 971 | } else if (mtod(m, struct ip_fw *)->fw_number == (u_short)-1) { |
---|
| 972 | dprintf(("%s can't delete rule 65535\n", err_prefix)); |
---|
| 973 | error = EINVAL; |
---|
| 974 | } else |
---|
| 975 | error = del_entry(&ip_fw_chain, |
---|
| 976 | mtod(m, struct ip_fw *)->fw_number); |
---|
| 977 | if (m) (void)m_free(m); |
---|
| 978 | return error; |
---|
| 979 | } |
---|
| 980 | |
---|
| 981 | dprintf(("%s unknown request %d\n", err_prefix, stage)); |
---|
| 982 | if (m) (void)m_free(m); |
---|
| 983 | return (EINVAL); |
---|
| 984 | } |
---|
| 985 | |
---|
| 986 | void |
---|
| 987 | ip_fw_init(void) |
---|
| 988 | { |
---|
| 989 | struct ip_fw default_rule; |
---|
| 990 | |
---|
| 991 | ip_fw_chk_ptr = ip_fw_chk; |
---|
| 992 | ip_fw_ctl_ptr = ip_fw_ctl; |
---|
| 993 | LIST_INIT(&ip_fw_chain); |
---|
| 994 | |
---|
| 995 | bzero(&default_rule, sizeof default_rule); |
---|
| 996 | default_rule.fw_prot = IPPROTO_IP; |
---|
| 997 | default_rule.fw_number = (u_short)-1; |
---|
| 998 | #ifdef IPFIREWALL_DEFAULT_TO_ACCEPT |
---|
| 999 | default_rule.fw_flg |= IP_FW_F_ACCEPT; |
---|
| 1000 | #else |
---|
| 1001 | default_rule.fw_flg |= IP_FW_F_DENY; |
---|
| 1002 | #endif |
---|
| 1003 | default_rule.fw_flg |= IP_FW_F_IN | IP_FW_F_OUT; |
---|
| 1004 | if (check_ipfw_struct(&default_rule) == NULL || |
---|
| 1005 | add_entry(&ip_fw_chain, &default_rule)) |
---|
| 1006 | panic(__FUNCTION__); |
---|
| 1007 | |
---|
| 1008 | printf("IP packet filtering initialized, " |
---|
| 1009 | #ifdef IPDIVERT |
---|
| 1010 | "divert enabled, "); |
---|
| 1011 | #else |
---|
| 1012 | "divert disabled, "); |
---|
| 1013 | #endif |
---|
| 1014 | #ifdef IPFIREWALL_DEFAULT_TO_ACCEPT |
---|
| 1015 | printf("default to accept, "); |
---|
| 1016 | #endif |
---|
| 1017 | #ifndef IPFIREWALL_VERBOSE |
---|
| 1018 | printf("logging disabled\n"); |
---|
| 1019 | #else |
---|
| 1020 | if (fw_verbose_limit == 0) |
---|
| 1021 | printf("unlimited logging\n"); |
---|
| 1022 | else |
---|
| 1023 | printf("logging limited to %d packets/entry\n", |
---|
| 1024 | fw_verbose_limit); |
---|
| 1025 | #endif |
---|
| 1026 | } |
---|
| 1027 | |
---|
| 1028 | #ifdef IPFIREWALL_MODULE |
---|
| 1029 | |
---|
| 1030 | #include <sys/exec.h> |
---|
| 1031 | #include <sys/sysent.h> |
---|
| 1032 | #include <sys/lkm.h> |
---|
| 1033 | |
---|
| 1034 | MOD_MISC(ipfw); |
---|
| 1035 | |
---|
| 1036 | static int |
---|
| 1037 | ipfw_load(struct lkm_table *lkmtp, int cmd) |
---|
| 1038 | { |
---|
| 1039 | int s=splnet(); |
---|
| 1040 | |
---|
| 1041 | old_chk_ptr = ip_fw_chk_ptr; |
---|
| 1042 | old_ctl_ptr = ip_fw_ctl_ptr; |
---|
| 1043 | |
---|
| 1044 | ip_fw_init(); |
---|
| 1045 | splx(s); |
---|
| 1046 | return 0; |
---|
| 1047 | } |
---|
| 1048 | |
---|
| 1049 | static int |
---|
| 1050 | ipfw_unload(struct lkm_table *lkmtp, int cmd) |
---|
| 1051 | { |
---|
| 1052 | int s=splnet(); |
---|
| 1053 | |
---|
| 1054 | ip_fw_chk_ptr = old_chk_ptr; |
---|
| 1055 | ip_fw_ctl_ptr = old_ctl_ptr; |
---|
| 1056 | |
---|
| 1057 | while (ip_fw_chain.lh_first != NULL) { |
---|
| 1058 | struct ip_fw_chain *fcp = ip_fw_chain.lh_first; |
---|
| 1059 | LIST_REMOVE(ip_fw_chain.lh_first, chain); |
---|
| 1060 | free(fcp->rule, M_IPFW); |
---|
| 1061 | free(fcp, M_IPFW); |
---|
| 1062 | } |
---|
| 1063 | |
---|
| 1064 | splx(s); |
---|
| 1065 | printf("IP firewall unloaded\n"); |
---|
| 1066 | return 0; |
---|
| 1067 | } |
---|
| 1068 | |
---|
| 1069 | int |
---|
| 1070 | ipfw_mod(struct lkm_table *lkmtp, int cmd, int ver) |
---|
| 1071 | { |
---|
| 1072 | DISPATCH(lkmtp, cmd, ver, ipfw_load, ipfw_unload, lkm_nullcmd); |
---|
| 1073 | } |
---|
| 1074 | #endif |
---|