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