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
  47 #include <stdio.h>
  48
  49 #include "netdissect-ctype.h"
  50
  51 #include "netdissect.h"
  52 #include "extract.h"
  53
  54 #define ASCII_LINELENGTH 300
  55 #define HEXDUMP_BYTES_PER_LINE 16
  56 #define HEXDUMP_SHORTS_PER_LINE (HEXDUMP_BYTES_PER_LINE / 2)
  57 #define HEXDUMP_HEXSTUFF_PER_SHORT 5 /* 4 hex digits and a space */
  58 #define HEXDUMP_HEXSTUFF_PER_LINE \
  59                 (HEXDUMP_HEXSTUFF_PER_SHORT * HEXDUMP_SHORTS_PER_LINE)
  60
  61 void
  62 ascii_print(netdissect_options *ndo,
  63             const u_char *cp, u_int length)
  64 {
  65         u_int caplength;
  66         u_char s;
  67         int truncated = FALSE;
  68
  69         ndo->ndo_protocol = "ascii";
  70         caplength = ND_BYTES_AVAILABLE_AFTER(cp);
  71         if (length > caplength) {
  72                 length = caplength;
  73                 truncated = TRUE;
  74         }
  75         ND_PRINT("\n");
  76         while (length != 0) {
  77                 s = GET_U_1(cp);
  78                 cp++;
  79                 length--;
  80                 if (s == '\r') {
  81                         /*
  82                          * Don't print CRs at the end of the line; they
  83                          * don't belong at the ends of lines on UN*X,
  84                          * and the standard I/O library will give us one
  85                          * on Windows so we don't need to print one
  86                          * ourselves.
  87                          *
  88                          * In the middle of a line, just print a '.'.
  89                          */
  90                         if (length > 1 && GET_U_1(cp) != '\n')
  91                                 ND_PRINT(".");
  92                 } else {
  93                         if (!ND_ASCII_ISGRAPH(s) &&
  94                             (s != '\t' && s != ' ' && s != '\n'))
  95                                 ND_PRINT(".");
  96                         else
  97                                 ND_PRINT("%c", s);
  98                 }
  99         }
 100         if (truncated)
 101                 nd_trunc_longjmp(ndo);
 102 }
 103
 104 static void
 105 hex_and_ascii_print_with_offset(netdissect_options *ndo, const char *indent,
 106                                 const u_char *cp, u_int length, u_int offset)
 107 {
 108         u_int caplength;
 109         u_int i;
 110         u_int s1, s2;
 111         u_int nshorts;
 112         int truncated = FALSE;
 113         char hexstuff[HEXDUMP_SHORTS_PER_LINE*HEXDUMP_HEXSTUFF_PER_SHORT+1], *hsp;
 114         char asciistuff[ASCII_LINELENGTH+1], *asp;
 115
 116         caplength = ND_BYTES_AVAILABLE_AFTER(cp);
 117         if (length > caplength) {
 118                 length = caplength;
 119                 truncated = TRUE;
 120         }
 121         nshorts = length / sizeof(u_short);
 122         i = 0;
 123         hsp = hexstuff; asp = asciistuff;
 124         while (nshorts != 0) {
 125                 s1 = GET_U_1(cp);
 126                 cp++;
 127                 s2 = GET_U_1(cp);
 128                 cp++;
 129                 (void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
 130                     " %02x%02x", s1, s2);
 131                 hsp += HEXDUMP_HEXSTUFF_PER_SHORT;
 132                 *(asp++) = (char)(ND_ASCII_ISGRAPH(s1) ? s1 : '.');
 133                 *(asp++) = (char)(ND_ASCII_ISGRAPH(s2) ? s2 : '.');
 134                 i++;
 135                 if (i >= HEXDUMP_SHORTS_PER_LINE) {
 136                         *hsp = *asp = '\0';
 137                         ND_PRINT("%s0x%04x: %-*s  %s",
 138                             indent, offset, HEXDUMP_HEXSTUFF_PER_LINE,
 139                             hexstuff, asciistuff);
 140                         i = 0; hsp = hexstuff; asp = asciistuff;
 141                         offset += HEXDUMP_BYTES_PER_LINE;
 142                 }
 143                 nshorts--;
 144         }
 145         if (length & 1) {
 146                 s1 = GET_U_1(cp);
 147                 cp++;
 148                 (void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
 149                     " %02x", s1);
 150                 hsp += 3;
 151                 *(asp++) = (char)(ND_ASCII_ISGRAPH(s1) ? s1 : '.');
 152                 ++i;
 153         }
 154         if (i > 0) {
 155                 *hsp = *asp = '\0';
 156                 ND_PRINT("%s0x%04x: %-*s  %s",
 157                      indent, offset, HEXDUMP_HEXSTUFF_PER_LINE,
 158                      hexstuff, asciistuff);
 159         }
 160         if (truncated)
 161                 nd_trunc_longjmp(ndo);
 162 }
 163
 164 void
 165 hex_and_ascii_print(netdissect_options *ndo, const char *indent,
 166                     const u_char *cp, u_int length)
 167 {
 168         hex_and_ascii_print_with_offset(ndo, indent, cp, length, 0);
 169 }
 170
 171 /*
 172  * telnet_print() wants this.  It is essentially default_print_unaligned()
 173  */
 174 void
 175 hex_print_with_offset(netdissect_options *ndo,
 176                       const char *indent, const u_char *cp, u_int length,
 177                       u_int offset)
 178 {
 179         u_int caplength;
 180         u_int i, s;
 181         u_int nshorts;
 182         int truncated = FALSE;
 183
 184         caplength = ND_BYTES_AVAILABLE_AFTER(cp);
 185         if (length > caplength) {
 186                 length = caplength;
 187                 truncated = TRUE;
 188         }
 189         nshorts = length / sizeof(u_short);
 190         i = 0;
 191         while (nshorts != 0) {
 192                 if ((i++ % 8) == 0) {
 193                         ND_PRINT("%s0x%04x: ", indent, offset);
 194                         offset += HEXDUMP_BYTES_PER_LINE;
 195                 }
 196                 s = GET_U_1(cp);
 197                 cp++;
 198                 ND_PRINT(" %02x%02x", s, GET_U_1(cp));
 199                 cp++;
 200                 nshorts--;
 201         }
 202         if (length & 1) {
 203                 if ((i % 8) == 0)
 204                         ND_PRINT("%s0x%04x: ", indent, offset);
 205                 ND_PRINT(" %02x", GET_U_1(cp));
 206         }
 207         if (truncated)
 208                 nd_trunc_longjmp(ndo);
 209 }
 210
 211 void
 212 hex_print(netdissect_options *ndo,
 213           const char *indent, const u_char *cp, u_int length)
 214 {
 215         hex_print_with_offset(ndo, indent, cp, length, 0);
 216 }