xref: /freebsd/contrib/tcpdump/print-ascii.c (revision a5921bc3653e2e286715e6fe8d473ec0d02da38c)
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 #define NETDISSECT_REWORKED
40 #ifdef HAVE_CONFIG_H
41 #include "config.h"
42 #endif
43 
44 #include <tcpdump-stdinc.h>
45 #include <stdio.h>
46 
47 #include "interface.h"
48 
49 #define ASCII_LINELENGTH 300
50 #define HEXDUMP_BYTES_PER_LINE 16
51 #define HEXDUMP_SHORTS_PER_LINE (HEXDUMP_BYTES_PER_LINE / 2)
52 #define HEXDUMP_HEXSTUFF_PER_SHORT 5 /* 4 hex digits and a space */
53 #define HEXDUMP_HEXSTUFF_PER_LINE \
54 		(HEXDUMP_HEXSTUFF_PER_SHORT * HEXDUMP_SHORTS_PER_LINE)
55 
56 void
57 ascii_print(netdissect_options *ndo,
58             const u_char *cp, u_int length)
59 {
60 	u_int caplength;
61 	register u_char s;
62 
63 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
64 	if (length > caplength)
65 		length = caplength;
66 	ND_PRINT((ndo, "\n"));
67 	while (length > 0) {
68 		s = *cp++;
69 		length--;
70 		if (s == '\r') {
71 			/*
72 			 * Don't print CRs at the end of the line; they
73 			 * don't belong at the ends of lines on UN*X,
74 			 * and the standard I/O library will give us one
75 			 * on Windows so we don't need to print one
76 			 * ourselves.
77 			 *
78 			 * In the middle of a line, just print a '.'.
79 			 */
80 			if (length > 1 && *cp != '\n')
81 				ND_PRINT((ndo, "."));
82 		} else {
83 			if (!ND_ISGRAPH(s) &&
84 			    (s != '\t' && s != ' ' && s != '\n'))
85 				ND_PRINT((ndo, "."));
86 			else
87 				ND_PRINT((ndo, "%c", s));
88 		}
89 	}
90 }
91 
92 void
93 hex_and_ascii_print_with_offset(netdissect_options *ndo, register const char *ident,
94     register const u_char *cp, register u_int length, register u_int oset)
95 {
96 	u_int caplength;
97 	register u_int i;
98 	register int s1, s2;
99 	register int nshorts;
100 	char hexstuff[HEXDUMP_SHORTS_PER_LINE*HEXDUMP_HEXSTUFF_PER_SHORT+1], *hsp;
101 	char asciistuff[ASCII_LINELENGTH+1], *asp;
102 
103 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
104 	if (length > caplength)
105 		length = caplength;
106 	nshorts = length / sizeof(u_short);
107 	i = 0;
108 	hsp = hexstuff; asp = asciistuff;
109 	while (--nshorts >= 0) {
110 		s1 = *cp++;
111 		s2 = *cp++;
112 		(void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
113 		    " %02x%02x", s1, s2);
114 		hsp += HEXDUMP_HEXSTUFF_PER_SHORT;
115 		*(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
116 		*(asp++) = (ND_ISGRAPH(s2) ? s2 : '.');
117 		i++;
118 		if (i >= HEXDUMP_SHORTS_PER_LINE) {
119 			*hsp = *asp = '\0';
120 			ND_PRINT((ndo, "%s0x%04x: %-*s  %s",
121 			    ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
122 			    hexstuff, asciistuff));
123 			i = 0; hsp = hexstuff; asp = asciistuff;
124 			oset += HEXDUMP_BYTES_PER_LINE;
125 		}
126 	}
127 	if (length & 1) {
128 		s1 = *cp++;
129 		(void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
130 		    " %02x", s1);
131 		hsp += 3;
132 		*(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
133 		++i;
134 	}
135 	if (i > 0) {
136 		*hsp = *asp = '\0';
137 		ND_PRINT((ndo, "%s0x%04x: %-*s  %s",
138 		     ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
139 		     hexstuff, asciistuff));
140 	}
141 }
142 
143 void
144 hex_and_ascii_print(netdissect_options *ndo, register const char *ident,
145     register const u_char *cp, register u_int length)
146 {
147 	hex_and_ascii_print_with_offset(ndo, ident, cp, length, 0);
148 }
149 
150 /*
151  * telnet_print() wants this.  It is essentially default_print_unaligned()
152  */
153 void
154 hex_print_with_offset(netdissect_options *ndo,
155                       const char *ident, const u_char *cp, u_int length,
156 		      u_int oset)
157 {
158 	u_int caplength;
159 	register u_int i, s;
160 	register int nshorts;
161 
162 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
163 	if (length > caplength)
164 		length = caplength;
165 	nshorts = (u_int) length / sizeof(u_short);
166 	i = 0;
167 	while (--nshorts >= 0) {
168 		if ((i++ % 8) == 0) {
169 			ND_PRINT((ndo,"%s0x%04x: ", ident, oset));
170 			oset += HEXDUMP_BYTES_PER_LINE;
171 		}
172 		s = *cp++;
173 		ND_PRINT((ndo," %02x%02x", s, *cp++));
174 	}
175 	if (length & 1) {
176 		if ((i % 8) == 0)
177 			ND_PRINT((ndo,"%s0x%04x: ", ident, oset));
178 		ND_PRINT((ndo," %02x", *cp));
179 	}
180 }
181 
182 /*
183  * just for completeness
184  */
185 void
186 hex_print(netdissect_options *ndo,const char *ident, const u_char *cp, u_int length)
187 {
188   hex_print_with_offset(ndo, ident, cp, length, 0);
189 }
190 
191 #ifdef MAIN
192 int
193 main(int argc, char *argv[])
194 {
195 	hex_print("\n\t", "Hello, World!\n", 14);
196 	printf("\n");
197 	hex_and_ascii_print("\n\t", "Hello, World!\n", 14);
198 	printf("\n");
199 	ascii_print("Hello, World!\n", 14);
200 	printf("\n");
201 #define TMSG "Now is the winter of our discontent...\n"
202 	hex_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
203 	printf("\n");
204 	hex_and_ascii_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
205 	printf("\n");
206 	exit(0);
207 }
208 #endif /* MAIN */
209