The Tcpdump Group git mirrors - tcpdump/blob - print-ascii.c

   1 /*      $NetBSD: print-ascii.c,v 1.1 1999/09/30 14:49:12 sjg Exp $      */
   2
   3 /*-
   4  * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Alan Barrett and Simon J. Gerraty.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *        This product includes software developed by the NetBSD
  21  *        Foundation, Inc. and its contributors.
  22  * 4. Neither the name of The NetBSD Foundation nor the names of its
  23  *    contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  36  * POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 /* \summary: ASCII packet dump printer */
  40
  41 #include <config.h>
  42
  43 #include "netdissect-stdinc.h"
  44
  45 #include <stdio.h>
  46
  47 #include "netdissect-ctype.h"
  48
  49 #include "netdissect.h"
  50 #include "extract.h"
  51
  52 #define ASCII_LINELENGTH 300
  53 #define HEXDUMP_BYTES_PER_LINE 16
  54 #define HEXDUMP_SHORTS_PER_LINE (HEXDUMP_BYTES_PER_LINE / 2)
  55 #define HEXDUMP_HEXSTUFF_PER_SHORT 5 /* 4 hex digits and a space */
  56 #define HEXDUMP_HEXSTUFF_PER_LINE \
  57                 (HEXDUMP_HEXSTUFF_PER_SHORT * HEXDUMP_SHORTS_PER_LINE)
  58
  59 void
  60 ascii_print(netdissect_options *ndo,
  61             const u_char *cp, u_int length)
  62 {
  63         u_int caplength;
  64         u_char s;
  65         int truncated = FALSE;
  66
  67         ndo->ndo_protocol = "ascii";
  68         caplength = ND_BYTES_AVAILABLE_AFTER(cp);
  69         if (length > caplength) {
  70                 length = caplength;
  71                 truncated = TRUE;
  72         }
  73         ND_PRINT("\n");
  74         while (length != 0) {
  75                 s = GET_U_1(cp);
  76                 cp++;
  77                 length--;
  78                 if (s == '\r') {
  79                         /*
  80                          * Don't print CRs at the end of the line; they
  81                          * don't belong at the ends of lines on UN*X,
  82                          * and the standard I/O library will give us one
  83                          * on Windows so we don't need to print one
  84                          * ourselves.
  85                          *
  86                          * In the middle of a line, just print a '.'.
  87                          */
  88                         if (length > 1 && GET_U_1(cp) != '\n')
  89                                 ND_PRINT(".");
  90                 } else {
  91                         if (!ND_ASCII_ISGRAPH(s) &&
  92                             (s != '\t' && s != ' ' && s != '\n'))
  93                                 ND_PRINT(".");
  94                         else
  95                                 ND_PRINT("%c", s);
  96                 }
  97         }
  98         if (truncated)
  99                 nd_trunc_longjmp(ndo);
 100 }
 101
 102 static void
 103 hex_and_ascii_print_with_offset(netdissect_options *ndo, const char *indent,
 104                                 const u_char *cp, u_int length, u_int offset)
 105 {
 106         u_int caplength;
 107         u_int i;
 108         u_int s1, s2;
 109         u_int nshorts;
 110         int truncated = FALSE;
 111         char hexstuff[HEXDUMP_SHORTS_PER_LINE*HEXDUMP_HEXSTUFF_PER_SHORT+1], *hsp;
 112         char asciistuff[ASCII_LINELENGTH+1], *asp;
 113
 114         caplength = ND_BYTES_AVAILABLE_AFTER(cp);
 115         if (length > caplength) {
 116                 length = caplength;
 117                 truncated = TRUE;
 118         }
 119         nshorts = length / sizeof(u_short);
 120         i = 0;
 121         hsp = hexstuff; asp = asciistuff;
 122         while (nshorts != 0) {
 123                 s1 = GET_U_1(cp);
 124                 cp++;
 125                 s2 = GET_U_1(cp);
 126                 cp++;
 127                 (void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
 128                     " %02x%02x", s1, s2);
 129                 hsp += HEXDUMP_HEXSTUFF_PER_SHORT;
 130                 *(asp++) = (char)(ND_ASCII_ISGRAPH(s1) ? s1 : '.');
 131                 *(asp++) = (char)(ND_ASCII_ISGRAPH(s2) ? s2 : '.');
 132                 i++;
 133                 if (i >= HEXDUMP_SHORTS_PER_LINE) {
 134                         *hsp = *asp = '\0';
 135                         ND_PRINT("%s0x%04x: %-*s  %s",
 136                             indent, offset, HEXDUMP_HEXSTUFF_PER_LINE,
 137                             hexstuff, asciistuff);
 138                         i = 0; hsp = hexstuff; asp = asciistuff;
 139                         offset += HEXDUMP_BYTES_PER_LINE;
 140                 }
 141                 nshorts--;
 142         }
 143         if (length & 1) {
 144                 s1 = GET_U_1(cp);
 145                 cp++;
 146                 (void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
 147                     " %02x", s1);
 148                 hsp += 3;
 149                 *(asp++) = (char)(ND_ASCII_ISGRAPH(s1) ? s1 : '.');
 150                 ++i;
 151         }
 152         if (i > 0) {
 153                 *hsp = *asp = '\0';
 154                 ND_PRINT("%s0x%04x: %-*s  %s",
 155                      indent, offset, HEXDUMP_HEXSTUFF_PER_LINE,
 156                      hexstuff, asciistuff);
 157         }
 158         if (truncated)
 159                 nd_trunc_longjmp(ndo);
 160 }
 161
 162 void
 163 hex_and_ascii_print(netdissect_options *ndo, const char *indent,
 164                     const u_char *cp, u_int length)
 165 {
 166         hex_and_ascii_print_with_offset(ndo, indent, cp, length, 0);
 167 }
 168
 169 /*
 170  * telnet_print() wants this.  It is essentially default_print_unaligned()
 171  */
 172 void
 173 hex_print_with_offset(netdissect_options *ndo,
 174                       const char *indent, const u_char *cp, u_int length,
 175                       u_int offset)
 176 {
 177         u_int caplength;
 178         u_int i, s;
 179         u_int nshorts;
 180         int truncated = FALSE;
 181
 182         caplength = ND_BYTES_AVAILABLE_AFTER(cp);
 183         if (length > caplength) {
 184                 length = caplength;
 185                 truncated = TRUE;
 186         }
 187         nshorts = length / sizeof(u_short);
 188         i = 0;
 189         while (nshorts != 0) {
 190                 if ((i++ % 8) == 0) {
 191                         ND_PRINT("%s0x%04x: ", indent, offset);
 192                         offset += HEXDUMP_BYTES_PER_LINE;
 193                 }
 194                 s = GET_U_1(cp);
 195                 cp++;
 196                 ND_PRINT(" %02x%02x", s, GET_U_1(cp));
 197                 cp++;
 198                 nshorts--;
 199         }
 200         if (length & 1) {
 201                 if ((i % 8) == 0)
 202                         ND_PRINT("%s0x%04x: ", indent, offset);
 203                 ND_PRINT(" %02x", GET_U_1(cp));
 204         }
 205         if (truncated)
 206                 nd_trunc_longjmp(ndo);
 207 }
 208
 209 void
 210 hex_print(netdissect_options *ndo,
 211           const char *indent, const u_char *cp, u_int length)
 212 {
 213         hex_print_with_offset(ndo, indent, cp, length, 0);
 214 }