xref: /netbsd-src/external/bsd/tcpdump/dist/print-ascii.c (revision cc576e1d8e4f4078fd4e81238abca9fca216f6ec)
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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __RCSID("$NetBSD: print-ascii.c,v 1.6 2017/01/24 23:29:13 christos Exp $");
35 #endif
36 
37 #ifdef HAVE_CONFIG_H
38 #include "config.h"
39 #endif
40 
41 #include <netdissect-stdinc.h>
42 #include <stdio.h>
43 
44 #include "netdissect.h"
45 
46 #define ASCII_LINELENGTH 300
47 #define HEXDUMP_BYTES_PER_LINE 16
48 #define HEXDUMP_SHORTS_PER_LINE (HEXDUMP_BYTES_PER_LINE / 2)
49 #define HEXDUMP_HEXSTUFF_PER_SHORT 5 /* 4 hex digits and a space */
50 #define HEXDUMP_HEXSTUFF_PER_LINE \
51 		(HEXDUMP_HEXSTUFF_PER_SHORT * HEXDUMP_SHORTS_PER_LINE)
52 
53 void
54 ascii_print(netdissect_options *ndo,
55             const u_char *cp, u_int length)
56 {
57 	u_int caplength;
58 	register u_char s;
59 
60 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
61 	if (length > caplength)
62 		length = caplength;
63 	ND_PRINT((ndo, "\n"));
64 	while (length > 0) {
65 		s = *cp++;
66 		length--;
67 		if (s == '\r') {
68 			/*
69 			 * Don't print CRs at the end of the line; they
70 			 * don't belong at the ends of lines on UN*X,
71 			 * and the standard I/O library will give us one
72 			 * on Windows so we don't need to print one
73 			 * ourselves.
74 			 *
75 			 * In the middle of a line, just print a '.'.
76 			 */
77 			if (length > 1 && *cp != '\n')
78 				ND_PRINT((ndo, "."));
79 		} else {
80 			if (!ND_ISGRAPH(s) &&
81 			    (s != '\t' && s != ' ' && s != '\n'))
82 				ND_PRINT((ndo, "."));
83 			else
84 				ND_PRINT((ndo, "%c", s));
85 		}
86 	}
87 }
88 
89 void
90 hex_and_ascii_print_with_offset(netdissect_options *ndo, register const char *ident,
91     register const u_char *cp, register u_int length, register u_int oset)
92 {
93 	u_int caplength;
94 	register u_int i;
95 	register int s1, s2;
96 	register int nshorts;
97 	char hexstuff[HEXDUMP_SHORTS_PER_LINE*HEXDUMP_HEXSTUFF_PER_SHORT+1], *hsp;
98 	char asciistuff[ASCII_LINELENGTH+1], *asp;
99 
100 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
101 	if (length > caplength)
102 		length = caplength;
103 	nshorts = length / sizeof(u_short);
104 	i = 0;
105 	hsp = hexstuff; asp = asciistuff;
106 	while (--nshorts >= 0) {
107 		s1 = *cp++;
108 		s2 = *cp++;
109 		(void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
110 		    " %02x%02x", s1, s2);
111 		hsp += HEXDUMP_HEXSTUFF_PER_SHORT;
112 		*(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
113 		*(asp++) = (ND_ISGRAPH(s2) ? s2 : '.');
114 		i++;
115 		if (i >= HEXDUMP_SHORTS_PER_LINE) {
116 			*hsp = *asp = '\0';
117 			ND_PRINT((ndo, "%s0x%04x: %-*s  %s",
118 			    ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
119 			    hexstuff, asciistuff));
120 			i = 0; hsp = hexstuff; asp = asciistuff;
121 			oset += HEXDUMP_BYTES_PER_LINE;
122 		}
123 	}
124 	if (length & 1) {
125 		s1 = *cp++;
126 		(void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
127 		    " %02x", s1);
128 		hsp += 3;
129 		*(asp++) = (ND_ISGRAPH(s1) ? s1 : '.');
130 		++i;
131 	}
132 	if (i > 0) {
133 		*hsp = *asp = '\0';
134 		ND_PRINT((ndo, "%s0x%04x: %-*s  %s",
135 		     ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
136 		     hexstuff, asciistuff));
137 	}
138 }
139 
140 void
141 hex_and_ascii_print(netdissect_options *ndo, register const char *ident,
142     register const u_char *cp, register u_int length)
143 {
144 	hex_and_ascii_print_with_offset(ndo, ident, cp, length, 0);
145 }
146 
147 /*
148  * telnet_print() wants this.  It is essentially default_print_unaligned()
149  */
150 void
151 hex_print_with_offset(netdissect_options *ndo,
152                       const char *ident, const u_char *cp, u_int length,
153 		      u_int oset)
154 {
155 	u_int caplength;
156 	register u_int i, s;
157 	register int nshorts;
158 
159 	caplength = (ndo->ndo_snapend >= cp) ? ndo->ndo_snapend - cp : 0;
160 	if (length > caplength)
161 		length = caplength;
162 	nshorts = (u_int) length / sizeof(u_short);
163 	i = 0;
164 	while (--nshorts >= 0) {
165 		if ((i++ % 8) == 0) {
166 			ND_PRINT((ndo,"%s0x%04x: ", ident, oset));
167 			oset += HEXDUMP_BYTES_PER_LINE;
168 		}
169 		s = *cp++;
170 		ND_PRINT((ndo," %02x%02x", s, *cp++));
171 	}
172 	if (length & 1) {
173 		if ((i % 8) == 0)
174 			ND_PRINT((ndo,"%s0x%04x: ", ident, oset));
175 		ND_PRINT((ndo," %02x", *cp));
176 	}
177 }
178 
179 /*
180  * just for completeness
181  */
182 void
183 hex_print(netdissect_options *ndo,const char *ident, const u_char *cp, u_int length)
184 {
185   hex_print_with_offset(ndo, ident, cp, length, 0);
186 }
187 
188 #ifdef MAIN
189 int
190 main(int argc, char *argv[])
191 {
192 	hex_print("\n\t", "Hello, World!\n", 14);
193 	printf("\n");
194 	hex_and_ascii_print("\n\t", "Hello, World!\n", 14);
195 	printf("\n");
196 	ascii_print("Hello, World!\n", 14);
197 	printf("\n");
198 #define TMSG "Now is the winter of our discontent...\n"
199 	hex_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
200 	printf("\n");
201 	hex_and_ascii_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
202 	printf("\n");
203 	exit(0);
204 }
205 #endif /* MAIN */
206