print-udp.c

Windump3.6.2源代码

	union {
		struct {
			struct in6_addr ph_src;
			struct in6_addr ph_dst;
			u_int32_t	ph_len;
			u_int8_t	ph_zero[3];
			u_int8_t	ph_nxt;
		} ph;
		u_int16_t pa[20];
	} phu;

	tlen = ntohs(ip6->ip6_plen) + sizeof(struct ip6_hdr) -
	    ((const char *)up - (const char*)ip6);

	/* pseudo-header */
	memset(&phu, 0, sizeof(phu));
	phu.ph.ph_src = ip6->ip6_src;
	phu.ph.ph_dst = ip6->ip6_dst;
	phu.ph.ph_len = htonl(tlen);
	phu.ph.ph_nxt = IPPROTO_UDP;

	sum = 0;
	for (i = 0; i < sizeof(phu.pa) / sizeof(phu.pa[0]); i++)
		sum += phu.pa[i];

	sp = (const u_int16_t *)up;

	for (i = 0; i < (tlen & ~1); i += 2)
		sum += *sp++;

	if (tlen & 1)
		sum += htons((*(const u_int8_t *)sp) << 8);

	while (sum > 0xffff)
		sum = (sum & 0xffff) + (sum >> 16);
	sum = ~sum & 0xffff;

	return (sum);
}
#endif


/* XXX probably should use getservbyname() and cache answers */
#define TFTP_PORT 69		/*XXX*/
#define KERBEROS_PORT 88	/*XXX*/
#define SUNRPC_PORT 111		/*XXX*/
#define SNMP_PORT 161		/*XXX*/
#define NTP_PORT 123		/*XXX*/
#define SNMPTRAP_PORT 162	/*XXX*/
#define ISAKMP_PORT 500		/*XXX*/
#define TIMED_PORT 525		/*XXX*/
#define RIP_PORT 520		/*XXX*/
#define KERBEROS_SEC_PORT 750	/*XXX*/
#define L2TP_PORT 1701		/*XXX*/
#define ISAKMP_PORT_USER1 7500	/*??? - nonstandard*/
#define ISAKMP_PORT_USER2 8500	/*??? - nonstandard*/
#define RX_PORT_LOW 7000	/*XXX*/
#define RX_PORT_HIGH 7009	/*XXX*/
#define NETBIOS_NS_PORT   137
#define NETBIOS_DGRAM_PORT   138
#define CISCO_AUTORP_PORT 496	/*XXX*/
#define RADIUS_PORT 1645
#define RADIUS_NEW_PORT 1812
#define RADIUS_ACCOUNTING_PORT 1646
#define RADIUS_NEW_ACCOUNTING_PORT 1813

#ifdef INET6
#define RIPNG_PORT 521		/*XXX*/
#define DHCP6_SERV_PORT 546	/*XXX*/
#define DHCP6_CLI_PORT 547	/*XXX*/
#endif

void
udp_print(register const u_char *bp, u_int length,
	  register const u_char *bp2, int fragmented)
{
	register const struct udphdr *up;
	register const struct ip *ip;
	register const u_char *cp;
	register const u_char *ep = bp + length;
	u_int16_t sport, dport, ulen;
#ifdef INET6
	register const struct ip6_hdr *ip6;
#endif

	if (ep > snapend)
		ep = snapend;
	up = (struct udphdr *)bp;
	ip = (struct ip *)bp2;
#ifdef INET6
	if (IP_V(ip) == 6)
		ip6 = (struct ip6_hdr *)bp2;
	else
		ip6 = NULL;
#endif /*INET6*/
	cp = (u_char *)(up + 1);
	if (cp > snapend) {
		(void)printf("%s > %s: [|udp]",
			ipaddr_string(&ip->ip_src), ipaddr_string(&ip->ip_dst));
		return;
	}
	if (length < sizeof(struct udphdr)) {
		(void)printf("%s > %s: truncated-udp %d",
			ipaddr_string(&ip->ip_src), ipaddr_string(&ip->ip_dst),
			length);
		return;
	}
	length -= sizeof(struct udphdr);

	sport = ntohs(up->uh_sport);
	dport = ntohs(up->uh_dport);
	ulen = ntohs(up->uh_ulen);
	if (ulen < 8) {
		(void)printf("%s > %s: truncated-udplength %d",
			     ipaddr_string(&ip->ip_src),
			     ipaddr_string(&ip->ip_dst),
			     ulen);
		return;
	}
	if (packettype) {
		register struct rpc_msg *rp;
		enum msg_type direction;

		switch (packettype) {

		case PT_VAT:
			(void)printf("%s.%s > %s.%s:",
				ipaddr_string(&ip->ip_src),
				udpport_string(sport),
				ipaddr_string(&ip->ip_dst),
				udpport_string(dport));
			vat_print((void *)(up + 1), length, up);
			break;

		case PT_WB:
			(void)printf("%s.%s > %s.%s:",
				ipaddr_string(&ip->ip_src),
				udpport_string(sport),
				ipaddr_string(&ip->ip_dst),
				udpport_string(dport));
			wb_print((void *)(up + 1), length);
			break;

		case PT_RPC:
			rp = (struct rpc_msg *)(up + 1);
			direction = (enum msg_type)ntohl(rp->rm_direction);
			if (direction == CALL)
				sunrpcrequest_print((u_char *)rp, length,
				    (u_char *)ip);
			else
				nfsreply_print((u_char *)rp, length,
				    (u_char *)ip);			/*XXX*/
			break;

		case PT_RTP:
			(void)printf("%s.%s > %s.%s:",
				ipaddr_string(&ip->ip_src),
				udpport_string(sport),
				ipaddr_string(&ip->ip_dst),
				udpport_string(dport));
			rtp_print((void *)(up + 1), length, up);
			break;

		case PT_RTCP:
			(void)printf("%s.%s > %s.%s:",
				ipaddr_string(&ip->ip_src),
				udpport_string(sport),
				ipaddr_string(&ip->ip_dst),
				udpport_string(dport));
			while (cp < ep)
				cp = rtcp_print(cp, ep);
			break;

		case PT_SNMP:
			(void)printf("%s.%s > %s.%s:",
				ipaddr_string(&ip->ip_src),
				udpport_string(sport),
				ipaddr_string(&ip->ip_dst),
				udpport_string(dport));
			snmp_print((const u_char *)(up + 1), length);
			break;

		case PT_CNFP:
			(void)printf("%s.%s > %s.%s:",
				ipaddr_string(&ip->ip_src),
				udpport_string(sport),
				ipaddr_string(&ip->ip_dst),
				udpport_string(dport));
			cnfp_print(cp, length, (const u_char *)ip);
			break;
		}
		return;
	}

	if (!qflag) {
		register struct rpc_msg *rp;
		enum msg_type direction;

		rp = (struct rpc_msg *)(up + 1);
		if (TTEST(rp->rm_direction)) {
			direction = (enum msg_type)ntohl(rp->rm_direction);
			if (dport == NFS_PORT && direction == CALL) {
				nfsreq_print((u_char *)rp, length,
				    (u_char *)ip);
				return;
			}
			if (sport == NFS_PORT && direction == REPLY) {
				nfsreply_print((u_char *)rp, length,
				    (u_char *)ip);
				return;
			}
#ifdef notdef
			if (dport == SUNRPC_PORT && direction == CALL) {
				sunrpcrequest_print((u_char *)rp, length, (u_char *)ip);
				return;
			}
#endif
		}
		if (TTEST(((struct LAP *)cp)->type) &&
		    ((struct LAP *)cp)->type == lapDDP &&
		    (atalk_port(sport) || atalk_port(dport))) {
			if (vflag)
				fputs("kip ", stdout);
			llap_print(cp, length);
			return;
		}
	}
#if 0
	(void)printf("%s.%s > %s.%s:",
		ipaddr_string(&ip->ip_src), udpport_string(sport),
		ipaddr_string(&ip->ip_dst), udpport_string(dport));
#else
#ifdef INET6
	if (ip6) {
		if (ip6->ip6_nxt == IPPROTO_UDP) {
			(void)printf("%s.%s > %s.%s: ",
				ip6addr_string(&ip6->ip6_src),
				udpport_string(sport),
				ip6addr_string(&ip6->ip6_dst),
				udpport_string(dport));
		} else {
			(void)printf("%s > %s: ",
				udpport_string(sport), udpport_string(dport));
		}
	} else
#endif /*INET6*/
	{
		if (ip->ip_p == IPPROTO_UDP) {
			(void)printf("%s.%s > %s.%s: ",
				ipaddr_string(&ip->ip_src),
				udpport_string(sport),
				ipaddr_string(&ip->ip_dst),
				udpport_string(dport));
		} else {
			(void)printf("%s > %s: ",
				udpport_string(sport), udpport_string(dport));
		}
	}
#endif

	if (IP_V(ip) == 4 && vflag && !fragmented) {
		int sum = up->uh_sum;
		if (sum == 0) {
			(void)printf(" [no cksum]");
		} else if (TTEST2(cp[0], length)) {
			sum = udp_cksum(ip, up, length);
			if (sum != 0)
				(void)printf(" [bad udp cksum %x!]", sum);
			else
				(void)printf(" [udp sum ok]");
		}
	}
#ifdef INET6
	if (IP_V(ip) == 6 && ip6->ip6_plen && vflag && !fragmented) {
		int sum = up->uh_sum;
		/* for IPv6, UDP checksum is mandatory */
		if (TTEST2(cp[0], length)) {
			sum = udp6_cksum(ip6, up, length);
			if (sum != 0)
				(void)printf(" [bad udp cksum %x!]", sum);
			else
				(void)printf(" [udp sum ok]");
		}
	}
#endif

	if (!qflag) {
#define ISPORT(p) (dport == (p) || sport == (p))
		if (ISPORT(NAMESERVER_PORT))
			ns_print((const u_char *)(up + 1), length);
		else if (ISPORT(TIMED_PORT))
			timed_print((const u_char *)(up + 1), length);
		else if (ISPORT(TFTP_PORT))
			tftp_print((const u_char *)(up + 1), length);
		else if (ISPORT(IPPORT_BOOTPC) || ISPORT(IPPORT_BOOTPS))
			bootp_print((const u_char *)(up + 1), length,
			    sport, dport);
		else if (ISPORT(RIP_PORT))
			rip_print((const u_char *)(up + 1), length);
		else if (ISPORT(ISAKMP_PORT))
			isakmp_print((const u_char *)(up + 1), length, bp2);
#if 1 /*???*/
		else if (ISPORT(ISAKMP_PORT_USER1) || ISPORT(ISAKMP_PORT_USER2))
			isakmp_print((const u_char *)(up + 1), length, bp2);
#endif
		else if (ISPORT(SNMP_PORT) || ISPORT(SNMPTRAP_PORT))
			snmp_print((const u_char *)(up + 1), length);
		else if (ISPORT(NTP_PORT))
			ntp_print((const u_char *)(up + 1), length);
		else if (ISPORT(KERBEROS_PORT) || ISPORT(KERBEROS_SEC_PORT))
			krb_print((const void *)(up + 1), length);
		else if (ISPORT(L2TP_PORT))
			l2tp_print((const u_char *)(up + 1), length);
 		else if (ISPORT(NETBIOS_NS_PORT)) {
			nbt_udp137_print((const u_char *)(up + 1), length);
 		}
 		else if (ISPORT(NETBIOS_DGRAM_PORT)) {
 			nbt_udp138_print((const u_char *)(up + 1), length);
 		}
		else if (dport == 3456)
			vat_print((const void *)(up + 1), length, up);
 		/*
 		 * Since there are 10 possible ports to check, I think
 		 * a <> test would be more efficient
 		 */
 		else if ((sport >= RX_PORT_LOW && sport <= RX_PORT_HIGH) ||
 			 (dport >= RX_PORT_LOW && dport <= RX_PORT_HIGH))
 			rx_print((const void *)(up + 1), length, sport, dport,
 				 (u_char *) ip);
#ifdef INET6
		else if (ISPORT(RIPNG_PORT))
			ripng_print((const u_char *)(up + 1), length);
		else if (ISPORT(DHCP6_SERV_PORT) || ISPORT(DHCP6_CLI_PORT)) {
			dhcp6_print((const u_char *)(up + 1), length,
				sport, dport);
		}
#endif /*INET6*/
		/*
		 * Kludge in test for whiteboard packets.
		 */
		else if (dport == 4567)
			wb_print((const void *)(up + 1), length);
		else if (ISPORT(CISCO_AUTORP_PORT))
			cisco_autorp_print((const void *)(up + 1), length);
		else if (ISPORT(RADIUS_PORT) ||
		         ISPORT(RADIUS_NEW_PORT) ||
		         ISPORT(RADIUS_ACCOUNTING_PORT) || 
		         ISPORT(RADIUS_NEW_ACCOUNTING_PORT) )
		         radius_print((const u_char *)(up+1), length);
		else
			(void)printf(" udp %u",
			    (u_int32_t)(ulen - sizeof(*up)));
#undef ISPORT
	} else
		(void)printf(" udp %u", (u_int32_t)(ulen - sizeof(*up)));
}