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 #ifdef HAVE_CONFIG_H
  42 #include <config.h>
  43 #endif
  44
  45 #include "netdissect-stdinc.h"
  46 #include <stdio.h>
  47
  48 #include "netdissect.h"
  49 #include "extract.h"
  50
  51 #define ASCII_LINELENGTH 300
  52 #define HEXDUMP_BYTES_PER_LINE 16
  53 #define HEXDUMP_SHORTS_PER_LINE (HEXDUMP_BYTES_PER_LINE / 2)
  54 #define HEXDUMP_HEXSTUFF_PER_SHORT 5 /* 4 hex digits and a space */
  55 #define HEXDUMP_HEXSTUFF_PER_LINE \
  56                 (HEXDUMP_HEXSTUFF_PER_SHORT * HEXDUMP_SHORTS_PER_LINE)
  57
  58 void
  59 ascii_print(netdissect_options *ndo,
  60             const u_char *cp, u_int length)
  61 {
  62         u_int caplength;
  63         u_char s;
  64
  65         ndo->ndo_protocol = "ascii";
  66         caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
  67         if (length > caplength)
  68                 length = caplength;
  69         ND_PRINT("\n");
  70         while (length > 0) {
  71                 s = EXTRACT_U_1(cp);
  72                 cp++;
  73                 length--;
  74                 if (s == '\r') {
  75                         /*
  76                          * Don't print CRs at the end of the line; they
  77                          * don't belong at the ends of lines on UN*X,
  78                          * and the standard I/O library will give us one
  79                          * on Windows so we don't need to print one
  80                          * ourselves.
  81                          *
  82                          * In the middle of a line, just print a '.'.
  83                          */
  84                         if (length > 1 && EXTRACT_U_1(cp) != '\n')
  85                                 ND_PRINT(".");
  86                 } else {
  87                         if (!ND_ISGRAPH(s) &&
  88                             (s != '\t' && s != ' ' && s != '\n'))
  89                                 ND_PRINT(".");
  90                         else
  91                                 ND_PRINT("%c", s);
  92                 }
  93         }
  94 }
  95
  96 void
  97 hex_and_ascii_print_with_offset(netdissect_options *ndo, const char *ident,
  98     const u_char *cp, u_int length, u_int oset)
  99 {
 100         u_int caplength;
 101         u_int i;
 102         int s1, s2;
 103         int nshorts;
 104         char hexstuff[HEXDUMP_SHORTS_PER_LINE*HEXDUMP_HEXSTUFF_PER_SHORT+1], *hsp;
 105         char asciistuff[ASCII_LINELENGTH+1], *asp;
 106
 107         caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
 108         if (length > caplength)
 109                 length = caplength;
 110         nshorts = length / sizeof(u_short);
 111         i = 0;
 112         hsp = hexstuff; asp = asciistuff;
 113         while (--nshorts >= 0) {
 114                 s1 = EXTRACT_U_1(cp);
 115                 cp++;
 116                 s2 = EXTRACT_U_1(cp);
 117                 cp++;
 118                 (void)nd_snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
 119                     " %02x%02x", s1, s2);
 120                 hsp += HEXDUMP_HEXSTUFF_PER_SHORT;
 121                 *(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
 122                 *(asp++) = (ND_ISGRAPH(s2) ? s2 : '.');
 123                 i++;
 124                 if (i >= HEXDUMP_SHORTS_PER_LINE) {
 125                         *hsp = *asp = '\0';
 126                         ND_PRINT("%s0x%04x: %-*s  %s",
 127                             ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
 128                             hexstuff, asciistuff);
 129                         i = 0; hsp = hexstuff; asp = asciistuff;
 130                         oset += HEXDUMP_BYTES_PER_LINE;
 131                 }
 132         }
 133         if (length & 1) {
 134                 s1 = EXTRACT_U_1(cp);
 135                 cp++;
 136                 (void)nd_snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
 137                     " %02x", s1);
 138                 hsp += 3;
 139                 *(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
 140                 ++i;
 141         }
 142         if (i > 0) {
 143                 *hsp = *asp = '\0';
 144                 ND_PRINT("%s0x%04x: %-*s  %s",
 145                      ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
 146                      hexstuff, asciistuff);
 147         }
 148 }
 149
 150 void
 151 hex_and_ascii_print(netdissect_options *ndo, const char *ident,
 152     const u_char *cp, u_int length)
 153 {
 154         hex_and_ascii_print_with_offset(ndo, ident, cp, length, 0);
 155 }
 156
 157 /*
 158  * telnet_print() wants this.  It is essentially default_print_unaligned()
 159  */
 160 void
 161 hex_print_with_offset(netdissect_options *ndo,
 162                       const char *ident, const u_char *cp, u_int length,
 163                       u_int oset)
 164 {
 165         u_int caplength;
 166         u_int i, s;
 167         int nshorts;
 168
 169         caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
 170         if (length > caplength)
 171                 length = caplength;
 172         nshorts = (u_int) length / sizeof(u_short);
 173         i = 0;
 174         while (--nshorts >= 0) {
 175                 if ((i++ % 8) == 0) {
 176                         ND_PRINT("%s0x%04x: ", ident, oset);
 177                         oset += HEXDUMP_BYTES_PER_LINE;
 178                 }
 179                 s = EXTRACT_U_1(cp);
 180                 cp++;
 181                 ND_PRINT(" %02x%02x", s, EXTRACT_U_1(cp));
 182                 cp++;
 183         }
 184         if (length & 1) {
 185                 if ((i % 8) == 0)
 186                         ND_PRINT("%s0x%04x: ", ident, oset);
 187                 ND_PRINT(" %02x", EXTRACT_U_1(cp));
 188         }
 189 }
 190
 191 /*
 192  * just for completeness
 193  */
 194 void
 195 hex_print(netdissect_options *ndo,const char *ident, const u_char *cp, u_int length)
 196 {
 197   hex_print_with_offset(ndo, ident, cp, length, 0);
 198 }
 199
 200 #ifdef MAIN
 201 int
 202 main(int argc, char *argv[])
 203 {
 204         hex_print("\n\t", "Hello, World!\n", 14);
 205         printf("\n");
 206         hex_and_ascii_print("\n\t", "Hello, World!\n", 14);
 207         printf("\n");
 208         ascii_print("Hello, World!\n", 14);
 209         printf("\n");
 210 #define TMSG "Now is the winter of our discontent...\n"
 211         hex_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
 212         printf("\n");
 213         hex_and_ascii_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
 214         printf("\n");
 215         exit(0);
 216 }
 217 #endif /* MAIN */