tcpdump  4.99.1
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print-ascii.c
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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
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 = (ndo->ndo_snapend > cp) ? ND_BYTES_AVAILABLE_AFTER(cp) : 0;
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
106  const u_char *cp, u_int length, u_int oset)
107 {
108  u_int caplength;
109  u_int i;
110  u_int s1, s2;
111  u_int nshorts;
112  int truncated = FALSE;
114  char asciistuff[ASCII_LINELENGTH+1], *asp;
115 
116  caplength = (ndo->ndo_snapend > cp) ? ND_BYTES_AVAILABLE_AFTER(cp) : 0;
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);
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  ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
139  hexstuff, asciistuff);
140  i = 0; hsp = hexstuff; asp = asciistuff;
141  oset += 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  ident, oset, 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 *ident,
166  const u_char *cp, u_int length)
167 {
168  hex_and_ascii_print_with_offset(ndo, ident, cp, length, 0);
169 }
170 
171 /*
172  * telnet_print() wants this. It is essentially default_print_unaligned()
173  */
174 void
176  const char *ident, const u_char *cp, u_int length,
177  u_int oset)
178 {
179  u_int caplength;
180  u_int i, s;
181  u_int nshorts;
182  int truncated = FALSE;
183 
184  caplength = (ndo->ndo_snapend > cp) ? ND_BYTES_AVAILABLE_AFTER(cp) : 0;
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: ", ident, oset);
194  oset += 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: ", ident, oset);
205  ND_PRINT(" %02x", GET_U_1(cp));
206  }
207  if (truncated)
208  nd_trunc_longjmp(ndo);
209 }
210 
211 void
213  const char *ident, const u_char *cp, u_int length)
214 {
215  hex_print_with_offset(ndo, ident, cp, length, 0);
216 }
217 
218 #ifdef MAIN
219 int
220 main(int argc, char *argv[])
221 {
222  hex_print("\n\t", "Hello, World!\n", 14);
223  printf("\n");
224  hex_and_ascii_print("\n\t", "Hello, World!\n", 14);
225  printf("\n");
226  ascii_print("Hello, World!\n", 14);
227  printf("\n");
228 #define TMSG "Now is the winter of our discontent...\n"
229  hex_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
230  printf("\n");
231  hex_and_ascii_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
232  printf("\n");
233  exit(0);
234 }
235 #endif /* MAIN */
#define GET_U_1(p)
Definition: extract.h:872
static void nd_trunc_longjmp(netdissect_options *ndo)
Definition: extract.h:579
#define ND_ASCII_ISGRAPH(c)
#define TRUE
#define FALSE
#define ND_PRINT(...)
Definition: netdissect.h:385
#define ND_BYTES_AVAILABLE_AFTER(p)
Definition: netdissect.h:383
int snprintf(char *, size_t, const char *,...)
int printf(const char *,...)
#define HEXDUMP_HEXSTUFF_PER_LINE
Definition: print-ascii.c:58
void ascii_print(netdissect_options *ndo, const u_char *cp, u_int length)
Definition: print-ascii.c:62
void hex_print_with_offset(netdissect_options *ndo, const char *ident, const u_char *cp, u_int length, u_int oset)
Definition: print-ascii.c:175
static void hex_and_ascii_print_with_offset(netdissect_options *ndo, const char *ident, const u_char *cp, u_int length, u_int oset)
Definition: print-ascii.c:105
void hex_print(netdissect_options *ndo, const char *ident, const u_char *cp, u_int length)
Definition: print-ascii.c:212
#define HEXDUMP_SHORTS_PER_LINE
Definition: print-ascii.c:56
void hex_and_ascii_print(netdissect_options *ndo, const char *ident, const u_char *cp, u_int length)
Definition: print-ascii.c:165
#define ASCII_LINELENGTH
Definition: print-ascii.c:54
#define HEXDUMP_HEXSTUFF_PER_SHORT
Definition: print-ascii.c:57
#define HEXDUMP_BYTES_PER_LINE
Definition: print-ascii.c:55
const u_char * ndo_snapend
Definition: netdissect.h:239
const char * ndo_protocol
Definition: netdissect.h:218
int main(int argc, char **argv)
Definition: tcpdump.c:1462