xref: /freebsd/contrib/tcpdump/print-ascii.c (revision c5f3a7f62217f20f0c7b2c4fc3fb2646336b0802)
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 #include <config.h>
42 
43 #include "netdissect-stdinc.h"
44 
45 #include <stdio.h>
46 
47 #include "netdissect-ctype.h"
48 
49 #include "netdissect.h"
50 #include "extract.h"
51 
52 #define ASCII_LINELENGTH 300
53 #define HEXDUMP_BYTES_PER_LINE 16
54 #define HEXDUMP_SHORTS_PER_LINE (HEXDUMP_BYTES_PER_LINE / 2)
55 #define HEXDUMP_HEXSTUFF_PER_SHORT 5 /* 4 hex digits and a space */
56 #define HEXDUMP_HEXSTUFF_PER_LINE \
57 		(HEXDUMP_HEXSTUFF_PER_SHORT * HEXDUMP_SHORTS_PER_LINE)
58 
59 void
60 ascii_print(netdissect_options *ndo,
61             const u_char *cp, u_int length)
62 {
63 	u_int caplength;
64 	u_char s;
65 	int truncated = FALSE;
66 
67 	ndo->ndo_protocol = "ascii";
68 	caplength = ND_BYTES_AVAILABLE_AFTER(cp);
69 	if (length > caplength) {
70 		length = caplength;
71 		truncated = TRUE;
72 	}
73 	ND_PRINT("\n");
74 	while (length > 0) {
75 		s = GET_U_1(cp);
76 		cp++;
77 		length--;
78 		if (s == '\r') {
79 			/*
80 			 * Don't print CRs at the end of the line; they
81 			 * don't belong at the ends of lines on UN*X,
82 			 * and the standard I/O library will give us one
83 			 * on Windows so we don't need to print one
84 			 * ourselves.
85 			 *
86 			 * In the middle of a line, just print a '.'.
87 			 */
88 			if (length > 1 && GET_U_1(cp) != '\n')
89 				ND_PRINT(".");
90 		} else {
91 			if (!ND_ASCII_ISGRAPH(s) &&
92 			    (s != '\t' && s != ' ' && s != '\n'))
93 				ND_PRINT(".");
94 			else
95 				ND_PRINT("%c", s);
96 		}
97 	}
98 	if (truncated)
99 		nd_trunc_longjmp(ndo);
100 }
101 
102 static void
103 hex_and_ascii_print_with_offset(netdissect_options *ndo, const char *ident,
104     const u_char *cp, u_int length, u_int oset)
105 {
106 	u_int caplength;
107 	u_int i;
108 	u_int s1, s2;
109 	u_int nshorts;
110 	int truncated = FALSE;
111 	char hexstuff[HEXDUMP_SHORTS_PER_LINE*HEXDUMP_HEXSTUFF_PER_SHORT+1], *hsp;
112 	char asciistuff[ASCII_LINELENGTH+1], *asp;
113 
114 	caplength = ND_BYTES_AVAILABLE_AFTER(cp);
115 	if (length > caplength) {
116 		length = caplength;
117 		truncated = TRUE;
118 	}
119 	nshorts = length / sizeof(u_short);
120 	i = 0;
121 	hsp = hexstuff; asp = asciistuff;
122 	while (nshorts != 0) {
123 		s1 = GET_U_1(cp);
124 		cp++;
125 		s2 = GET_U_1(cp);
126 		cp++;
127 		(void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
128 		    " %02x%02x", s1, s2);
129 		hsp += HEXDUMP_HEXSTUFF_PER_SHORT;
130 		*(asp++) = (char)(ND_ASCII_ISGRAPH(s1) ? s1 : '.');
131 		*(asp++) = (char)(ND_ASCII_ISGRAPH(s2) ? s2 : '.');
132 		i++;
133 		if (i >= HEXDUMP_SHORTS_PER_LINE) {
134 			*hsp = *asp = '\0';
135 			ND_PRINT("%s0x%04x: %-*s  %s",
136 			    ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
137 			    hexstuff, asciistuff);
138 			i = 0; hsp = hexstuff; asp = asciistuff;
139 			oset += HEXDUMP_BYTES_PER_LINE;
140 		}
141 		nshorts--;
142 	}
143 	if (length & 1) {
144 		s1 = GET_U_1(cp);
145 		cp++;
146 		(void)snprintf(hsp, sizeof(hexstuff) - (hsp - hexstuff),
147 		    " %02x", s1);
148 		hsp += 3;
149 		*(asp++) = (char)(ND_ASCII_ISGRAPH(s1) ? s1 : '.');
150 		++i;
151 	}
152 	if (i > 0) {
153 		*hsp = *asp = '\0';
154 		ND_PRINT("%s0x%04x: %-*s  %s",
155 		     ident, oset, HEXDUMP_HEXSTUFF_PER_LINE,
156 		     hexstuff, asciistuff);
157 	}
158 	if (truncated)
159 		nd_trunc_longjmp(ndo);
160 }
161 
162 void
163 hex_and_ascii_print(netdissect_options *ndo, const char *ident,
164     const u_char *cp, u_int length)
165 {
166 	hex_and_ascii_print_with_offset(ndo, ident, cp, length, 0);
167 }
168 
169 /*
170  * telnet_print() wants this.  It is essentially default_print_unaligned()
171  */
172 void
173 hex_print_with_offset(netdissect_options *ndo,
174                       const char *ident, const u_char *cp, u_int length,
175 		      u_int oset)
176 {
177 	u_int caplength;
178 	u_int i, s;
179 	u_int nshorts;
180 	int truncated = FALSE;
181 
182 	caplength = ND_BYTES_AVAILABLE_AFTER(cp);
183 	if (length > caplength) {
184 		length = caplength;
185 		truncated = TRUE;
186 	}
187 	nshorts = length / sizeof(u_short);
188 	i = 0;
189 	while (nshorts != 0) {
190 		if ((i++ % 8) == 0) {
191 			ND_PRINT("%s0x%04x: ", ident, oset);
192 			oset += HEXDUMP_BYTES_PER_LINE;
193 		}
194 		s = GET_U_1(cp);
195 		cp++;
196 		ND_PRINT(" %02x%02x", s, GET_U_1(cp));
197 		cp++;
198 		nshorts--;
199 	}
200 	if (length & 1) {
201 		if ((i % 8) == 0)
202 			ND_PRINT("%s0x%04x: ", ident, oset);
203 		ND_PRINT(" %02x", GET_U_1(cp));
204 	}
205 	if (truncated)
206 		nd_trunc_longjmp(ndo);
207 }
208 
209 void
210 hex_print(netdissect_options *ndo,
211 	  const char *ident, const u_char *cp, u_int length)
212 {
213 	hex_print_with_offset(ndo, ident, cp, length, 0);
214 }
215 
216 #ifdef MAIN
217 int
218 main(int argc, char *argv[])
219 {
220 	hex_print("\n\t", "Hello, World!\n", 14);
221 	printf("\n");
222 	hex_and_ascii_print("\n\t", "Hello, World!\n", 14);
223 	printf("\n");
224 	ascii_print("Hello, World!\n", 14);
225 	printf("\n");
226 #define TMSG "Now is the winter of our discontent...\n"
227 	hex_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
228 	printf("\n");
229 	hex_and_ascii_print_with_offset("\n\t", TMSG, sizeof(TMSG) - 1, 0x100);
230 	printf("\n");
231 	exit(0);
232 }
233 #endif /* MAIN */
234