xref: /freebsd/contrib/tcpdump/print-ascii.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
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 = (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
105 hex_and_ascii_print_with_offset(netdissect_options *ndo, const char *ident,
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;
113 	char hexstuff[HEXDUMP_SHORTS_PER_LINE*HEXDUMP_HEXSTUFF_PER_SHORT+1], *hsp;
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);
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 			    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
175 hex_print_with_offset(netdissect_options *ndo,
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
212 hex_print(netdissect_options *ndo,
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 */
236