xref: /freebsd/contrib/tcpdump/print-ascii.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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 
50 #define ASCII_LINELENGTH 300
51 #define HEXDUMP_BYTES_PER_LINE 16
52 #define HEXDUMP_SHORTS_PER_LINE (HEXDUMP_BYTES_PER_LINE / 2)
53 #define HEXDUMP_HEXSTUFF_PER_SHORT 5 /* 4 hex digits and a space */
54 #define HEXDUMP_HEXSTUFF_PER_LINE \
55 		(HEXDUMP_HEXSTUFF_PER_SHORT * HEXDUMP_SHORTS_PER_LINE)
56 
57 void
58 ascii_print(netdissect_options *ndo,
59             const u_char *cp, u_int length)
60 {
61 	u_int caplength;
62 	register u_char s;
63 
64 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
65 	if (length > caplength)
66 		length = caplength;
67 	ND_PRINT((ndo, "\n"));
68 	while (length > 0) {
69 		s = *cp++;
70 		length--;
71 		if (s == '\r') {
72 			/*
73 			 * Don't print CRs at the end of the line; they
74 			 * don't belong at the ends of lines on UN*X,
75 			 * and the standard I/O library will give us one
76 			 * on Windows so we don't need to print one
77 			 * ourselves.
78 			 *
79 			 * In the middle of a line, just print a '.'.
80 			 */
81 			if (length > 1 && *cp != '\n')
82 				ND_PRINT((ndo, "."));
83 		} else {
84 			if (!ND_ISGRAPH(s) &&
85 			    (s != '\t' && s != ' ' && s != '\n'))
86 				ND_PRINT((ndo, "."));
87 			else
88 				ND_PRINT((ndo, "%c", s));
89 		}
90 	}
91 }
92 
93 void
94 hex_and_ascii_print_with_offset(netdissect_options *ndo, register const char *ident,
95     register const u_char *cp, register u_int length, register u_int oset)
96 {
97 	u_int caplength;
98 	register u_int i;
99 	register int s1, s2;
100 	register int nshorts;
101 	char hexstuff[HEXDUMP_SHORTS_PER_LINE*HEXDUMP_HEXSTUFF_PER_SHORT+1], *hsp;
102 	char asciistuff[ASCII_LINELENGTH+1], *asp;
103 
104 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
105 	if (length > caplength)
106 		length = caplength;
107 	nshorts = length / sizeof(u_short);
108 	i = 0;
109 	hsp = hexstuff; asp = asciistuff;
110 	while (--nshorts >= 0) {
111 		s1 = *cp++;
112 		s2 = *cp++;
113 		(void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
114 		    " %02x%02x", s1, s2);
115 		hsp += HEXDUMP_HEXSTUFF_PER_SHORT;
116 		*(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
117 		*(asp++) = (ND_ISGRAPH(s2) ? s2 : '.');
118 		i++;
119 		if (i >= HEXDUMP_SHORTS_PER_LINE) {
120 			*hsp = *asp = '\0';
121 			ND_PRINT((ndo, "%s0x%04x: %-*s  %s",
122 			    ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
123 			    hexstuff, asciistuff));
124 			i = 0; hsp = hexstuff; asp = asciistuff;
125 			oset += HEXDUMP_BYTES_PER_LINE;
126 		}
127 	}
128 	if (length & 1) {
129 		s1 = *cp++;
130 		(void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
131 		    " %02x", s1);
132 		hsp += 3;
133 		*(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
134 		++i;
135 	}
136 	if (i > 0) {
137 		*hsp = *asp = '\0';
138 		ND_PRINT((ndo, "%s0x%04x: %-*s  %s",
139 		     ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
140 		     hexstuff, asciistuff));
141 	}
142 }
143 
144 void
145 hex_and_ascii_print(netdissect_options *ndo, register const char *ident,
146     register const u_char *cp, register u_int length)
147 {
148 	hex_and_ascii_print_with_offset(ndo, ident, cp, length, 0);
149 }
150 
151 /*
152  * telnet_print() wants this.  It is essentially default_print_unaligned()
153  */
154 void
155 hex_print_with_offset(netdissect_options *ndo,
156                       const char *ident, const u_char *cp, u_int length,
157 		      u_int oset)
158 {
159 	u_int caplength;
160 	register u_int i, s;
161 	register int nshorts;
162 
163 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
164 	if (length > caplength)
165 		length = caplength;
166 	nshorts = (u_int) length / sizeof(u_short);
167 	i = 0;
168 	while (--nshorts >= 0) {
169 		if ((i++ % 8) == 0) {
170 			ND_PRINT((ndo,"%s0x%04x: ", ident, oset));
171 			oset += HEXDUMP_BYTES_PER_LINE;
172 		}
173 		s = *cp++;
174 		ND_PRINT((ndo," %02x%02x", s, *cp++));
175 	}
176 	if (length & 1) {
177 		if ((i % 8) == 0)
178 			ND_PRINT((ndo,"%s0x%04x: ", ident, oset));
179 		ND_PRINT((ndo," %02x", *cp));
180 	}
181 }
182 
183 /*
184  * just for completeness
185  */
186 void
187 hex_print(netdissect_options *ndo,const char *ident, const u_char *cp, u_int length)
188 {
189   hex_print_with_offset(ndo, ident, cp, length, 0);
190 }
191 
192 #ifdef MAIN
193 int
194 main(int argc, char *argv[])
195 {
196 	hex_print("\n\t", "Hello, World!\n", 14);
197 	printf("\n");
198 	hex_and_ascii_print("\n\t", "Hello, World!\n", 14);
199 	printf("\n");
200 	ascii_print("Hello, World!\n", 14);
201 	printf("\n");
202 #define TMSG "Now is the winter of our discontent...\n"
203 	hex_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
204 	printf("\n");
205 	hex_and_ascii_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
206 	printf("\n");
207 	exit(0);
208 }
209 #endif /* MAIN */
210