usr/src/cmd/cmd-inet/usr.sbin/snoop/snoop_udp.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <stdio.h>
  30 #include <ctype.h>
  31 #include <string.h>
  32 #include <fcntl.h>
  33 #include <string.h>
  34 #include <sys/types.h>
  35 #include <sys/time.h>
  36
  37 #include <sys/socket.h>
  38 #include <sys/sockio.h>
  39 #include <net/if.h>
  40 #include <netinet/in_systm.h>
  41 #include <netinet/in.h>
  42 #include <netinet/ip.h>
  43 #include <netinet/if_ether.h>
  44 #include <netinet/udp.h>
  45 #include "snoop.h"
  46
  47 extern char *dlc_header;
  48
  49 int
  50 interpret_udp(int flags, struct udphdr *udp, int iplen, int fraglen)
  51 {
  52         char *data;
  53         int udplen;
  54         int sunrpc;
  55         char *pname;
  56         char buff [32];
  57
  58         if (fraglen < sizeof (struct udphdr))
  59                 return (fraglen);       /* incomplete header */
  60
  61         data = (char *)udp + sizeof (struct udphdr);
  62         udplen = ntohs((ushort_t)udp->uh_ulen) - sizeof (struct udphdr);
  63         fraglen -= sizeof (struct udphdr);
  64         if (fraglen > udplen)
  65                 fraglen = udplen;
  66
  67         if (flags & F_SUM) {
  68                 (void) sprintf(get_sum_line(),
  69                         "UDP D=%d S=%d LEN=%d",
  70                         ntohs(udp->uh_dport),
  71                         ntohs(udp->uh_sport),
  72                         ntohs((ushort_t)udp->uh_ulen));
  73         }
  74
  75         sunrpc = !reservedport(IPPROTO_UDP, ntohs(udp->uh_dport)) &&
  76                 !reservedport(IPPROTO_UDP, ntohs(udp->uh_sport)) &&
  77                 valid_rpc(data, udplen);
  78
  79         if (flags & F_DTAIL) {
  80                 show_header("UDP:  ", "UDP Header", udplen);
  81                 show_space();
  82                 (void) sprintf(get_line((char *)(uintptr_t)udp->uh_sport -
  83                     dlc_header, 1), "Source port = %d", ntohs(udp->uh_sport));
  84
  85                 if (sunrpc) {
  86                         pname = "(Sun RPC)";
  87                 } else {
  88                         pname = getportname(IPPROTO_UDP, ntohs(udp->uh_dport));
  89                         if (pname == NULL) {
  90                                 pname = "";
  91                         } else {
  92                                 (void) sprintf(buff, "(%s)", pname);
  93                                 pname = buff;
  94                         }
  95                 }
  96                 (void) sprintf(get_line((char *)(uintptr_t)udp->uh_dport -
  97                     dlc_header, 1), "Destination port = %d %s",
  98                     ntohs(udp->uh_dport), pname);
  99                 (void) sprintf(get_line((char *)(uintptr_t)udp->uh_ulen -
 100                     dlc_header, 1), "Length = %d %s",
 101                     ntohs((ushort_t)udp->uh_ulen),
 102                     udplen > fraglen ?
 103                         "(Not all data contained in this fragment)"
 104                         : "");
 105                     (void) sprintf(get_line((char *)(uintptr_t)udp->uh_sum -
 106                         dlc_header, 1), "Checksum = %04X %s",
 107                         ntohs(udp->uh_sum),
 108                         udp->uh_sum == 0 ? "(no checksum)" : "");
 109                 show_space();
 110         }
 111
 112
 113         /* go to the next protocol layer */
 114
 115         if (!interpret_reserved(flags, IPPROTO_UDP,
 116                 ntohs(udp->uh_sport),
 117                 ntohs(udp->uh_dport),
 118                 data, fraglen)) {
 119                 if (fraglen > 0 && sunrpc)
 120                         interpret_rpc(flags, data, fraglen, IPPROTO_UDP);
 121         }
 122
 123         return (fraglen);
 124 }