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((ndo, "\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((ndo, "."));
  85                 } else {
  86                         if (!ND_ISGRAPH(s) &&
  87                             (s != '\t' && s != ' ' && s != '\n'))
  88                                 ND_PRINT((ndo, "."));
  89                         else
  90                                 ND_PRINT((ndo, "%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 = *cp++;
 114                 s2 = *cp++;
 115                 (void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
 116                     " %02x%02x", s1, s2);
 117                 hsp += HEXDUMP_HEXSTUFF_PER_SHORT;
 118                 *(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
 119                 *(asp++) = (ND_ISGRAPH(s2) ? s2 : '.');
 120                 i++;
 121                 if (i >= HEXDUMP_SHORTS_PER_LINE) {
 122                         *hsp = *asp = '\0';
 123                         ND_PRINT((ndo, "%s0x%04x: %-*s  %s",
 124                             ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
 125                             hexstuff, asciistuff));
 126                         i = 0; hsp = hexstuff; asp = asciistuff;
 127                         oset += HEXDUMP_BYTES_PER_LINE;
 128                 }
 129         }
 130         if (length & 1) {
 131                 s1 = *cp++;
 132                 (void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
 133                     " %02x", s1);
 134                 hsp += 3;
 135                 *(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
 136                 ++i;
 137         }
 138         if (i > 0) {
 139                 *hsp = *asp = '\0';
 140                 ND_PRINT((ndo, "%s0x%04x: %-*s  %s",
 141                      ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
 142                      hexstuff, asciistuff));
 143         }
 144 }
 145
 146 void
 147 hex_and_ascii_print(netdissect_options *ndo, const char *ident,
 148     const u_char *cp, u_int length)
 149 {
 150         hex_and_ascii_print_with_offset(ndo, ident, cp, length, 0);
 151 }
 152
 153 /*
 154  * telnet_print() wants this.  It is essentially default_print_unaligned()
 155  */
 156 void
 157 hex_print_with_offset(netdissect_options *ndo,
 158                       const char *ident, const u_char *cp, u_int length,
 159                       u_int oset)
 160 {
 161         u_int caplength;
 162         u_int i, s;
 163         int nshorts;
 164
 165         caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
 166         if (length > caplength)
 167                 length = caplength;
 168         nshorts = (u_int) length / sizeof(u_short);
 169         i = 0;
 170         while (--nshorts >= 0) {
 171                 if ((i++ % 8) == 0) {
 172                         ND_PRINT((ndo,"%s0x%04x: ", ident, oset));
 173                         oset += HEXDUMP_BYTES_PER_LINE;
 174                 }
 175                 s = *cp++;
 176                 ND_PRINT((ndo," %02x%02x", s, *cp++));
 177         }
 178         if (length & 1) {
 179                 if ((i % 8) == 0)
 180                         ND_PRINT((ndo,"%s0x%04x: ", ident, oset));
 181                 ND_PRINT((ndo," %02x", *cp));
 182         }
 183 }
 184
 185 /*
 186  * just for completeness
 187  */
 188 void
 189 hex_print(netdissect_options *ndo,const char *ident, const u_char *cp, u_int length)
 190 {
 191   hex_print_with_offset(ndo, ident, cp, length, 0);
 192 }
 193
 194 #ifdef MAIN
 195 int
 196 main(int argc, char *argv[])
 197 {
 198         hex_print("\n\t", "Hello, World!\n", 14);
 199         printf("\n");
 200         hex_and_ascii_print("\n\t", "Hello, World!\n", 14);
 201         printf("\n");
 202         ascii_print("Hello, World!\n", 14);
 203         printf("\n");
 204 #define TMSG "Now is the winter of our discontent...\n"
 205         hex_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
 206         printf("\n");
 207         hex_and_ascii_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
 208         printf("\n");
 209         exit(0);
 210 }
 211 #endif /* MAIN */