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