741 lines
20 KiB
C
741 lines
20 KiB
C
/*
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* PPP IP Protocol Interface
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*
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* Written by Toshiharu OHNO (tony-o@iij.ad.jp)
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*
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* Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd.
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*
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* Redistribution and use in source and binary forms are permitted
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* provided that the above copyright notice and this paragraph are
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* duplicated in all such forms and that any documentation,
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* advertising materials, and other materials related to such
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* distribution and use acknowledge that the software was developed
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* by the Internet Initiative Japan. The name of the
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* IIJ may not be used to endorse or promote products derived
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* from this software without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*
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* $FreeBSD$
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*
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* TODO:
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* o Return ICMP message for filterd packet
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* and optionaly record it into log.
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*/
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#include <sys/param.h>
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#include <sys/socket.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_icmp.h>
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#include <netinet/udp.h>
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#include <netinet/tcp.h>
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#include <arpa/inet.h>
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#include <sys/un.h>
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#include <errno.h>
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#include <stdio.h>
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#include <string.h>
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#include <termios.h>
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#include <unistd.h>
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#include "layer.h"
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#include "proto.h"
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#include "mbuf.h"
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#include "log.h"
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#include "defs.h"
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#include "timer.h"
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#include "fsm.h"
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#include "lqr.h"
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#include "hdlc.h"
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#include "throughput.h"
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#include "iplist.h"
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#include "slcompress.h"
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#include "ipcp.h"
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#include "filter.h"
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#include "descriptor.h"
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#include "lcp.h"
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#include "ccp.h"
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#include "link.h"
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#include "mp.h"
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#ifndef NORADIUS
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#include "radius.h"
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#endif
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#include "bundle.h"
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#include "tun.h"
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#include "ip.h"
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#define OPCODE_QUERY 0
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#define OPCODE_IQUERY 1
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#define OPCODE_STATUS 2
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struct dns_header {
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u_short id;
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unsigned qr : 1;
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unsigned opcode : 4;
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unsigned aa : 1;
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unsigned tc : 1;
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unsigned rd : 1;
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unsigned ra : 1;
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unsigned z : 3;
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unsigned rcode : 4;
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u_short qdcount;
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u_short ancount;
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u_short nscount;
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u_short arcount;
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};
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static const char *
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dns_Qclass2Txt(u_short qclass)
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{
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static char failure[6];
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struct {
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u_short id;
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const char *txt;
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} qtxt[] = {
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/* rfc1035 */
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{ 1, "IN" }, { 2, "CS" }, { 3, "CH" }, { 4, "HS" }, { 255, "*" }
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};
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int f;
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for (f = 0; f < sizeof qtxt / sizeof *qtxt; f++)
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if (qtxt[f].id == qclass)
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return qtxt[f].txt;
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return HexStr(qclass, failure, sizeof failure);
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}
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static const char *
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dns_Qtype2Txt(u_short qtype)
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{
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static char failure[6];
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struct {
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u_short id;
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const char *txt;
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} qtxt[] = {
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/* rfc1035/rfc1700 */
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{ 1, "A" }, { 2, "NS" }, { 3, "MD" }, { 4, "MF" }, { 5, "CNAME" },
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{ 6, "SOA" }, { 7, "MB" }, { 8, "MG" }, { 9, "MR" }, { 10, "NULL" },
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{ 11, "WKS" }, { 12, "PTR" }, { 13, "HINFO" }, { 14, "MINFO" },
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{ 15, "MX" }, { 16, "TXT" }, { 17, "RP" }, { 18, "AFSDB" },
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{ 19, "X25" }, { 20, "ISDN" }, { 21, "RT" }, { 22, "NSAP" },
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{ 23, "NSAP-PTR" }, { 24, "SIG" }, { 25, "KEY" }, { 26, "PX" },
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{ 27, "GPOS" }, { 28, "AAAA" }, { 252, "AXFR" }, { 253, "MAILB" },
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{ 254, "MAILA" }, { 255, "*" }
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};
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int f;
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for (f = 0; f < sizeof qtxt / sizeof *qtxt; f++)
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if (qtxt[f].id == qtype)
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return qtxt[f].txt;
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return HexStr(qtype, failure, sizeof failure);
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}
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static __inline int
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PortMatch(int op, u_short pport, u_short rport)
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{
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switch (op) {
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case OP_EQ:
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return (pport == rport);
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case OP_GT:
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return (pport > rport);
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case OP_LT:
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return (pport < rport);
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default:
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return (0);
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}
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}
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/*
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* Check a packet against a defined filter
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* Returns 0 to accept the packet, non-zero to drop the packet
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*
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* If filtering is enabled, the initial fragment of a datagram must
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* contain the complete protocol header, and subsequent fragments
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* must not attempt to over-write it.
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*/
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static int
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FilterCheck(const struct ip *pip, const struct filter *filter)
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{
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int gotinfo; /* true if IP payload decoded */
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int cproto; /* P_* protocol type if (gotinfo) */
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int estab, syn, finrst; /* TCP state flags if (gotinfo) */
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u_short sport, dport; /* src, dest port from packet if (gotinfo) */
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int n; /* filter rule to process */
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int len; /* bytes used in dbuff */
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int didname; /* true if filter header printed */
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int match; /* true if condition matched */
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const struct filterent *fp = filter->rule;
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char dbuff[100];
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if (fp->f_action == A_NONE)
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return (0); /* No rule is given. Permit this packet */
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/* Deny any packet fragment that tries to over-write the header.
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* Since we no longer have the real header available, punt on the
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* largest normal header - 20 bytes for TCP without options, rounded
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* up to the next possible fragment boundary. Since the smallest
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* `legal' MTU is 576, and the smallest recommended MTU is 296, any
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* fragmentation within this range is dubious at best */
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len = ntohs(pip->ip_off) & IP_OFFMASK; /* fragment offset */
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if (len > 0) { /* Not first fragment within datagram */
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if (len < (24 >> 3)) /* don't allow fragment to over-write header */
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return (1);
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/* permit fragments on in and out filter */
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return (!filter->fragok);
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}
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cproto = gotinfo = estab = syn = finrst = didname = 0;
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sport = dport = 0;
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for (n = 0; n < MAXFILTERS; ) {
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if (fp->f_action == A_NONE) {
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n++;
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fp++;
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continue;
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}
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if (!didname) {
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log_Printf(LogDEBUG, "%s filter:\n", filter->name);
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didname = 1;
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}
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match = 0;
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if (!((pip->ip_src.s_addr ^ fp->f_src.ipaddr.s_addr) &
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fp->f_src.mask.s_addr) &&
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!((pip->ip_dst.s_addr ^ fp->f_dst.ipaddr.s_addr) &
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fp->f_dst.mask.s_addr)) {
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if (fp->f_proto != P_NONE) {
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if (!gotinfo) {
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const char *ptop = (const char *) pip + (pip->ip_hl << 2);
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const struct tcphdr *th;
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const struct udphdr *uh;
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const struct icmp *ih;
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int datalen; /* IP datagram length */
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datalen = ntohs(pip->ip_len) - (pip->ip_hl << 2);
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switch (pip->ip_p) {
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case IPPROTO_ICMP:
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cproto = P_ICMP;
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if (datalen < 8) /* ICMP must be at least 8 octets */
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return (1);
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ih = (const struct icmp *) ptop;
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sport = ih->icmp_type;
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estab = syn = finrst = -1;
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if (log_IsKept(LogDEBUG))
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snprintf(dbuff, sizeof dbuff, "sport = %d", sport);
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break;
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case IPPROTO_IGMP:
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cproto = P_IGMP;
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if (datalen < 8) /* IGMP uses 8-octet messages */
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return (1);
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estab = syn = finrst = -1;
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sport = ntohs(0);
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break;
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#ifdef IPPROTO_GRE
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case IPPROTO_GRE:
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cproto = P_GRE;
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if (datalen < 2) /* GRE uses 2-octet+ messages */
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return (1);
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estab = syn = finrst = -1;
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sport = ntohs(0);
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break;
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#endif
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#ifdef IPPROTO_OSPFIGP
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case IPPROTO_OSPFIGP:
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cproto = P_OSPF;
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if (datalen < 8) /* IGMP uses 8-octet messages */
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return (1);
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estab = syn = finrst = -1;
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sport = ntohs(0);
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break;
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#endif
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case IPPROTO_UDP:
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case IPPROTO_IPIP:
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cproto = P_UDP;
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if (datalen < 8) /* UDP header is 8 octets */
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return (1);
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uh = (const struct udphdr *) ptop;
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sport = ntohs(uh->uh_sport);
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dport = ntohs(uh->uh_dport);
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estab = syn = finrst = -1;
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if (log_IsKept(LogDEBUG))
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snprintf(dbuff, sizeof dbuff, "sport = %d, dport = %d",
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sport, dport);
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break;
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case IPPROTO_TCP:
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cproto = P_TCP;
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th = (const struct tcphdr *) ptop;
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/* TCP headers are variable length. The following code
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* ensures that the TCP header length isn't de-referenced if
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* the datagram is too short
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*/
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if (datalen < 20 || datalen < (th->th_off << 2))
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return (1);
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sport = ntohs(th->th_sport);
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dport = ntohs(th->th_dport);
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estab = (th->th_flags & TH_ACK);
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syn = (th->th_flags & TH_SYN);
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finrst = (th->th_flags & (TH_FIN|TH_RST));
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if (log_IsKept(LogDEBUG)) {
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if (!estab)
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snprintf(dbuff, sizeof dbuff,
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"flags = %02x, sport = %d, dport = %d",
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th->th_flags, sport, dport);
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else
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*dbuff = '\0';
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}
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break;
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default:
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return (1); /* We'll block unknown type of packet */
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}
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if (log_IsKept(LogDEBUG)) {
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if (estab != -1) {
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len = strlen(dbuff);
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snprintf(dbuff + len, sizeof dbuff - len,
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", estab = %d, syn = %d, finrst = %d",
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estab, syn, finrst);
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}
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log_Printf(LogDEBUG, " Filter: proto = %s, %s\n",
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filter_Proto2Nam(cproto), dbuff);
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}
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gotinfo = 1;
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}
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if (log_IsKept(LogDEBUG)) {
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if (fp->f_srcop != OP_NONE) {
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snprintf(dbuff, sizeof dbuff, ", src %s %d",
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filter_Op2Nam(fp->f_srcop), fp->f_srcport);
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len = strlen(dbuff);
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} else
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len = 0;
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if (fp->f_dstop != OP_NONE) {
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snprintf(dbuff + len, sizeof dbuff - len,
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", dst %s %d", filter_Op2Nam(fp->f_dstop),
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fp->f_dstport);
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} else if (!len)
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*dbuff = '\0';
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log_Printf(LogDEBUG, " rule = %d: Address match, "
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"check against proto %s%s, action = %s\n",
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n, filter_Proto2Nam(fp->f_proto),
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dbuff, filter_Action2Nam(fp->f_action));
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}
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if (cproto == fp->f_proto) {
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if ((fp->f_srcop == OP_NONE ||
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PortMatch(fp->f_srcop, sport, fp->f_srcport)) &&
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(fp->f_dstop == OP_NONE ||
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PortMatch(fp->f_dstop, dport, fp->f_dstport)) &&
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(fp->f_estab == 0 || estab) &&
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(fp->f_syn == 0 || syn) &&
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(fp->f_finrst == 0 || finrst)) {
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match = 1;
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}
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}
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} else {
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/* Address is matched and no protocol specified. Make a decision. */
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log_Printf(LogDEBUG, " rule = %d: Address match, action = %s\n", n,
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filter_Action2Nam(fp->f_action));
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match = 1;
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}
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} else
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log_Printf(LogDEBUG, " rule = %d: Address mismatch\n", n);
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if (match != fp->f_invert) {
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/* Take specified action */
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if (fp->f_action < A_NONE)
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fp = &filter->rule[n = fp->f_action];
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else
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return (fp->f_action != A_PERMIT);
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} else {
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n++;
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fp++;
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}
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}
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return (1); /* No rule is mached. Deny this packet */
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}
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#ifdef notdef
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static void
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IcmpError(struct ip *pip, int code)
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{
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struct mbuf *bp;
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if (pip->ip_p != IPPROTO_ICMP) {
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bp = m_get(m_len, MB_IPIN);
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memcpy(MBUF_CTOP(bp), ptr, m_len);
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vj_SendFrame(bp);
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ipcp_AddOutOctets(m_len);
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}
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}
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#endif
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static void
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ip_LogDNS(const struct udphdr *uh, const char *direction)
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{
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struct dns_header header;
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const u_short *pktptr;
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const u_char *ptr;
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u_short *hptr;
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int len;
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ptr = (const char *)uh + sizeof *uh;
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len = ntohs(uh->uh_ulen) - sizeof *uh;
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if (len < sizeof header + 5) /* rfc1024 */
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return;
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pktptr = (const u_short *)ptr;
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hptr = (u_short *)&header;
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ptr += sizeof header;
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len -= sizeof header;
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while (pktptr < (const u_short *)ptr) {
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*hptr++ = ntohs(*pktptr); /* Careful of macro side-effects ! */
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pktptr++;
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}
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if (header.opcode == OPCODE_QUERY && header.qr == 0) {
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/* rfc1035 */
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char name[MAXHOSTNAMELEN + 1], *n;
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const char *qtype, *qclass;
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const u_char *end;
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n = name;
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end = ptr + len - 4;
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if (end - ptr > MAXHOSTNAMELEN)
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end = ptr + MAXHOSTNAMELEN;
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while (ptr < end) {
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len = *ptr++;
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if (len > end - ptr)
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len = end - ptr;
|
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if (n != name)
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*n++ = '.';
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memcpy(n, ptr, len);
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ptr += len;
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n += len;
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}
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*n = '\0';
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qtype = dns_Qtype2Txt(ntohs(*(const u_short *)end));
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qclass = dns_Qclass2Txt(ntohs(*(const u_short *)(end + 2)));
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log_Printf(LogDNS, "%sbound query %s %s %s\n",
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direction, qclass, qtype, name);
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}
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}
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|
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/*
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* For debugging aid.
|
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*/
|
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int
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PacketCheck(struct bundle *bundle, char *cp, int nb, struct filter *filter)
|
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{
|
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static const char *const TcpFlags[] = {
|
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"FIN", "SYN", "RST", "PSH", "ACK", "URG"
|
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};
|
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struct ip *pip;
|
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struct tcphdr *th;
|
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struct udphdr *uh;
|
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struct icmp *icmph;
|
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char *ptop;
|
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int mask, len, n, pri, logit, loglen, result;
|
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char logbuf[200];
|
|
|
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logit = (log_IsKept(LogTCPIP) || log_IsKept(LogDNS)) &&
|
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(!filter || filter->logok);
|
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loglen = 0;
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pri = 0;
|
|
|
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pip = (struct ip *)cp;
|
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uh = NULL;
|
|
|
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if (logit && loglen < sizeof logbuf) {
|
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if (filter)
|
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snprintf(logbuf + loglen, sizeof logbuf - loglen, "%s ", filter->name);
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else
|
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snprintf(logbuf + loglen, sizeof logbuf - loglen, " ");
|
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loglen += strlen(logbuf + loglen);
|
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}
|
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ptop = (cp + (pip->ip_hl << 2));
|
|
|
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switch (pip->ip_p) {
|
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case IPPROTO_ICMP:
|
|
if (logit && loglen < sizeof logbuf) {
|
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icmph = (struct icmp *) ptop;
|
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snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
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"ICMP: %s:%d ---> ", inet_ntoa(pip->ip_src), icmph->icmp_type);
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loglen += strlen(logbuf + loglen);
|
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snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
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"%s:%d", inet_ntoa(pip->ip_dst), icmph->icmp_type);
|
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loglen += strlen(logbuf + loglen);
|
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}
|
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break;
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|
|
|
case IPPROTO_UDP:
|
|
uh = (struct udphdr *) ptop;
|
|
if (pip->ip_tos == IPTOS_LOWDELAY)
|
|
pri++;
|
|
|
|
if ((ntohs(pip->ip_off) & IP_OFFMASK) == 0 &&
|
|
ipcp_IsUrgentUdpPort(&bundle->ncp.ipcp, ntohs(uh->uh_sport),
|
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ntohs(uh->uh_dport)))
|
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pri++;
|
|
|
|
if (logit && loglen < sizeof logbuf) {
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"UDP: %s:%d ---> ", inet_ntoa(pip->ip_src), ntohs(uh->uh_sport));
|
|
loglen += strlen(logbuf + loglen);
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"%s:%d", inet_ntoa(pip->ip_dst), ntohs(uh->uh_dport));
|
|
loglen += strlen(logbuf + loglen);
|
|
}
|
|
break;
|
|
|
|
#ifdef IPPROTO_GRE
|
|
case IPPROTO_GRE:
|
|
if (logit && loglen < sizeof logbuf) {
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"GRE: %s ---> ", inet_ntoa(pip->ip_src));
|
|
loglen += strlen(logbuf + loglen);
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"%s", inet_ntoa(pip->ip_dst));
|
|
loglen += strlen(logbuf + loglen);
|
|
}
|
|
break;
|
|
#endif
|
|
|
|
#ifdef IPPROTO_OSPFIGP
|
|
case IPPROTO_OSPFIGP:
|
|
if (logit && loglen < sizeof logbuf) {
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"OSPF: %s ---> ", inet_ntoa(pip->ip_src));
|
|
loglen += strlen(logbuf + loglen);
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"%s", inet_ntoa(pip->ip_dst));
|
|
loglen += strlen(logbuf + loglen);
|
|
}
|
|
break;
|
|
#endif
|
|
|
|
case IPPROTO_IPIP:
|
|
if (logit && loglen < sizeof logbuf) {
|
|
uh = (struct udphdr *) ptop;
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"IPIP: %s:%d ---> ", inet_ntoa(pip->ip_src), ntohs(uh->uh_sport));
|
|
loglen += strlen(logbuf + loglen);
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"%s:%d", inet_ntoa(pip->ip_dst), ntohs(uh->uh_dport));
|
|
loglen += strlen(logbuf + loglen);
|
|
}
|
|
break;
|
|
|
|
case IPPROTO_IGMP:
|
|
if (logit && loglen < sizeof logbuf) {
|
|
uh = (struct udphdr *) ptop;
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"IGMP: %s:%d ---> ", inet_ntoa(pip->ip_src), ntohs(uh->uh_sport));
|
|
loglen += strlen(logbuf + loglen);
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"%s:%d", inet_ntoa(pip->ip_dst), ntohs(uh->uh_dport));
|
|
loglen += strlen(logbuf + loglen);
|
|
}
|
|
break;
|
|
|
|
case IPPROTO_TCP:
|
|
th = (struct tcphdr *) ptop;
|
|
if (pip->ip_tos == IPTOS_LOWDELAY)
|
|
pri++;
|
|
|
|
if ((ntohs(pip->ip_off) & IP_OFFMASK) == 0 &&
|
|
ipcp_IsUrgentTcpPort(&bundle->ncp.ipcp, ntohs(th->th_sport),
|
|
ntohs(th->th_dport)))
|
|
pri++;
|
|
|
|
if (logit && loglen < sizeof logbuf) {
|
|
len = ntohs(pip->ip_len) - (pip->ip_hl << 2) - (th->th_off << 2);
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"TCP: %s:%d ---> ", inet_ntoa(pip->ip_src), ntohs(th->th_sport));
|
|
loglen += strlen(logbuf + loglen);
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
"%s:%d", inet_ntoa(pip->ip_dst), ntohs(th->th_dport));
|
|
loglen += strlen(logbuf + loglen);
|
|
n = 0;
|
|
for (mask = TH_FIN; mask != 0x40; mask <<= 1) {
|
|
if (th->th_flags & mask) {
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen, " %s", TcpFlags[n]);
|
|
loglen += strlen(logbuf + loglen);
|
|
}
|
|
n++;
|
|
}
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
" seq:%lx ack:%lx (%d/%d)",
|
|
(u_long)ntohl(th->th_seq), (u_long)ntohl(th->th_ack), len, nb);
|
|
loglen += strlen(logbuf + loglen);
|
|
if ((th->th_flags & TH_SYN) && nb > 40) {
|
|
u_short *sp;
|
|
|
|
ptop += 20;
|
|
sp = (u_short *) ptop;
|
|
if (ntohs(sp[0]) == 0x0204) {
|
|
snprintf(logbuf + loglen, sizeof logbuf - loglen,
|
|
" MSS = %d", ntohs(sp[1]));
|
|
loglen += strlen(logbuf + loglen);
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
if (filter && FilterCheck(pip, filter)) {
|
|
if (logit)
|
|
log_Printf(LogTCPIP, "%s - BLOCKED\n", logbuf);
|
|
#ifdef notdef
|
|
if (direction == 0)
|
|
IcmpError(pip, pri);
|
|
#endif
|
|
result = -1;
|
|
} else {
|
|
/* Check Keep Alive filter */
|
|
if (logit && log_IsKept(LogTCPIP)) {
|
|
if (filter && FilterCheck(pip, &bundle->filter.alive))
|
|
log_Printf(LogTCPIP, "%s - NO KEEPALIVE\n", logbuf);
|
|
else
|
|
log_Printf(LogTCPIP, "%s\n", logbuf);
|
|
}
|
|
result = pri;
|
|
}
|
|
|
|
if (filter && uh && ntohs(uh->uh_dport) == 53 && log_IsKept(LogDNS))
|
|
ip_LogDNS(uh, filter->name);
|
|
|
|
return result;
|
|
}
|
|
|
|
struct mbuf *
|
|
ip_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
|
|
{
|
|
int nb, nw;
|
|
struct tun_data tun;
|
|
struct ip *pip;
|
|
char *data;
|
|
|
|
if (bundle->ncp.ipcp.fsm.state != ST_OPENED) {
|
|
log_Printf(LogWARN, "ip_Input: IPCP not open - packet dropped\n");
|
|
m_freem(bp);
|
|
return NULL;
|
|
}
|
|
|
|
m_settype(bp, MB_IPIN);
|
|
nb = m_length(bp);
|
|
if (nb > sizeof tun.data) {
|
|
log_Printf(LogWARN, "ip_Input: %s: Packet too large (got %d, max %d)\n",
|
|
l->name, nb, (int)(sizeof tun.data));
|
|
m_freem(bp);
|
|
return NULL;
|
|
}
|
|
mbuf_Read(bp, tun.data, nb);
|
|
|
|
if (PacketCheck(bundle, tun.data, nb, &bundle->filter.in) < 0)
|
|
return NULL;
|
|
|
|
pip = (struct ip *)tun.data;
|
|
if (!FilterCheck(pip, &bundle->filter.alive))
|
|
bundle_StartIdleTimer(bundle);
|
|
|
|
ipcp_AddInOctets(&bundle->ncp.ipcp, nb);
|
|
|
|
if (bundle->dev.header) {
|
|
tun.family = htonl(AF_INET);
|
|
nb += sizeof tun - sizeof tun.data;
|
|
data = (char *)&tun;
|
|
} else
|
|
data = tun.data;
|
|
|
|
nw = write(bundle->dev.fd, data, nb);
|
|
if (nw != nb) {
|
|
if (nw == -1)
|
|
log_Printf(LogERROR, "ip_Input: %s: wrote %d, got %s\n",
|
|
l->name, nb, strerror(errno));
|
|
else
|
|
log_Printf(LogERROR, "ip_Input: %s: wrote %d, got %d\n", l->name, nb, nw);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
void
|
|
ip_Enqueue(struct ipcp *ipcp, int pri, char *ptr, int count)
|
|
{
|
|
struct mbuf *bp;
|
|
|
|
if (pri < 0 || pri >= IPCP_QUEUES(ipcp))
|
|
log_Printf(LogERROR, "Can't store in ip queue %d\n", pri);
|
|
else {
|
|
/*
|
|
* We allocate an extra 6 bytes, four at the front and two at the end.
|
|
* This is an optimisation so that we need to do less work in
|
|
* m_prepend() in acf_LayerPush() and proto_LayerPush() and
|
|
* appending in hdlc_LayerPush().
|
|
*/
|
|
bp = m_get(count + 6, MB_IPOUT);
|
|
bp->m_offset += 4;
|
|
bp->m_len -= 6;
|
|
memcpy(MBUF_CTOP(bp), ptr, count);
|
|
m_enqueue(ipcp->Queue + pri, bp);
|
|
}
|
|
}
|
|
|
|
void
|
|
ip_DeleteQueue(struct ipcp *ipcp)
|
|
{
|
|
struct mqueue *queue;
|
|
|
|
for (queue = ipcp->Queue; queue < ipcp->Queue + IPCP_QUEUES(ipcp); queue++)
|
|
while (queue->top)
|
|
m_freem(m_dequeue(queue));
|
|
}
|
|
|
|
size_t
|
|
ip_QueueLen(struct ipcp *ipcp)
|
|
{
|
|
struct mqueue *queue;
|
|
size_t result;
|
|
|
|
result = 0;
|
|
for (queue = ipcp->Queue; queue < ipcp->Queue + IPCP_QUEUES(ipcp); queue++)
|
|
result += queue->len;
|
|
|
|
return result;
|
|
}
|
|
|
|
int
|
|
ip_PushPacket(struct link *l, struct bundle *bundle)
|
|
{
|
|
struct ipcp *ipcp = &bundle->ncp.ipcp;
|
|
struct mqueue *queue;
|
|
struct mbuf *bp;
|
|
struct ip *pip;
|
|
int m_len;
|
|
|
|
if (ipcp->fsm.state != ST_OPENED)
|
|
return 0;
|
|
|
|
queue = ipcp->Queue + IPCP_QUEUES(ipcp) - 1;
|
|
do {
|
|
if (queue->top) {
|
|
bp = m_pullup(m_dequeue(queue));
|
|
m_len = m_length(bp);
|
|
pip = (struct ip *)MBUF_CTOP(bp);
|
|
if (!FilterCheck(pip, &bundle->filter.alive))
|
|
bundle_StartIdleTimer(bundle);
|
|
link_PushPacket(l, bp, bundle, 0, PROTO_IP);
|
|
ipcp_AddOutOctets(ipcp, m_len);
|
|
return 1;
|
|
}
|
|
} while (queue-- != ipcp->Queue);
|
|
|
|
return 0;
|
|
}
|