1 /*
2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 #include "varattrs.h"
23 
24 #ifndef lint
25 static const char copyright[] _U_ =
26     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
27 The Regents of the University of California.  All rights reserved.\n";
28 #endif
29 
30 #include <pcap.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <stdarg.h>
35 #ifdef _WIN32
36   #include "getopt.h"
37 #else
38   #include <unistd.h>
39 #endif
40 #include <errno.h>
41 
42 #include "pcap/funcattrs.h"
43 
44 #ifdef _WIN32
45   #include "portability.h"
46 #endif
47 
48 #define MAXIMUM_SNAPLEN		262144
49 
50 static char *program_name;
51 
52 /* Forwards */
53 static void PCAP_NORETURN usage(void);
54 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
55 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
56 
57 int
58 main(int argc, char **argv)
59 {
60 	register int op;
61 	register char *cp, *device;
62 	int dorfmon, dopromisc, snaplen, useactivate, bufsize;
63 	char ebuf[PCAP_ERRBUF_SIZE];
64 	pcap_if_t *devlist;
65 	pcap_t *pd;
66 	int status = 0;
67 
68 	device = NULL;
69 	dorfmon = 0;
70 	dopromisc = 0;
71 	snaplen = MAXIMUM_SNAPLEN;
72 	bufsize = 0;
73 	useactivate = 0;
74 	if ((cp = strrchr(argv[0], '/')) != NULL)
75 		program_name = cp + 1;
76 	else
77 		program_name = argv[0];
78 
79 	opterr = 0;
80 	while ((op = getopt(argc, argv, "i:Ips:aB:")) != -1) {
81 		switch (op) {
82 
83 		case 'i':
84 			device = strdup(optarg);
85 			break;
86 
87 		case 'I':
88 			dorfmon = 1;
89 			useactivate = 1;	/* required for rfmon */
90 			break;
91 
92 		case 'p':
93 			dopromisc = 1;
94 			break;
95 
96 		case 's': {
97 			char *end;
98 			long long_snaplen;
99 
100 			long_snaplen = strtol(optarg, &end, 0);
101 			if (optarg == end || *end != '\0'
102 			    || long_snaplen < 0
103 			    || long_snaplen > MAXIMUM_SNAPLEN)
104 				error("invalid snaplen %s", optarg);
105 			else {
106 				if (snaplen == 0)
107 					snaplen = MAXIMUM_SNAPLEN;
108 				else
109 					snaplen = (int)long_snaplen;
110 			}
111 			break;
112 		}
113 
114 		case 'B':
115 			bufsize = atoi(optarg)*1024;
116 			if (bufsize <= 0)
117 				error("invalid packet buffer size %s", optarg);
118 			useactivate = 1;	/* required for bufsize */
119 			break;
120 
121 		case 'a':
122 			useactivate = 1;
123 			break;
124 
125 		default:
126 			usage();
127 			/* NOTREACHED */
128 		}
129 	}
130 
131 	if (device == NULL) {
132 		if (pcap_findalldevs(&devlist, ebuf) == -1)
133 			error("%s", ebuf);
134 		if (devlist == NULL)
135 			error("no interfaces available for capture");
136 		device = strdup(devlist->name);
137 		pcap_freealldevs(devlist);
138 	}
139 	if (useactivate) {
140 		pd = pcap_create(device, ebuf);
141 		if (pd == NULL)
142 			error("%s: pcap_create failed: %s", device, ebuf);
143 		status = pcap_set_snaplen(pd, snaplen);
144 		if (status != 0)
145 			error("%s: pcap_set_snaplen failed: %s",
146 			    device, pcap_statustostr(status));
147 		if (dopromisc) {
148 			status = pcap_set_promisc(pd, 1);
149 			if (status != 0)
150 				error("%s: pcap_set_promisc failed: %s",
151 				    device, pcap_statustostr(status));
152 		}
153 		if (dorfmon) {
154 			status = pcap_set_rfmon(pd, 1);
155 			if (status != 0)
156 				error("%s: pcap_set_rfmon failed: %s",
157 				    device, pcap_statustostr(status));
158 		}
159 		status = pcap_set_timeout(pd, 1000);
160 		if (status != 0)
161 			error("%s: pcap_set_timeout failed: %s",
162 			    device, pcap_statustostr(status));
163 		if (bufsize != 0) {
164 			status = pcap_set_buffer_size(pd, bufsize);
165 			if (status != 0)
166 				error("%s: pcap_set_buffer_size failed: %s",
167 				    device, pcap_statustostr(status));
168 		}
169 		status = pcap_activate(pd);
170 		if (status < 0) {
171 			/*
172 			 * pcap_activate() failed.
173 			 */
174 			error("%s: %s\n(%s)", device,
175 			    pcap_statustostr(status), pcap_geterr(pd));
176 		} else if (status > 0) {
177 			/*
178 			 * pcap_activate() succeeded, but it's warning us
179 			 * of a problem it had.
180 			 */
181 			warning("%s: %s\n(%s)", device,
182 			    pcap_statustostr(status), pcap_geterr(pd));
183 		} else
184 			printf("%s opened successfully\n", device);
185 	} else {
186 		*ebuf = '\0';
187 		pd = pcap_open_live(device, 65535, 0, 1000, ebuf);
188 		if (pd == NULL)
189 			error("%s", ebuf);
190 		else if (*ebuf)
191 			warning("%s", ebuf);
192 		else
193 			printf("%s opened successfully\n", device);
194 	}
195 	free(device);
196 	pcap_close(pd);
197 	exit(status < 0 ? 1 : 0);
198 }
199 
200 static void
201 usage(void)
202 {
203 	(void)fprintf(stderr,
204 	    "Usage: %s [ -Ipa ] [ -i interface ] [ -s snaplen ] [ -B bufsize ]\n",
205 	    program_name);
206 	exit(1);
207 }
208 
209 /* VARARGS */
210 static void
211 error(const char *fmt, ...)
212 {
213 	va_list ap;
214 
215 	(void)fprintf(stderr, "%s: ", program_name);
216 	va_start(ap, fmt);
217 	(void)vfprintf(stderr, fmt, ap);
218 	va_end(ap);
219 	if (*fmt) {
220 		fmt += strlen(fmt);
221 		if (fmt[-1] != '\n')
222 			(void)fputc('\n', stderr);
223 	}
224 	exit(1);
225 	/* NOTREACHED */
226 }
227 
228 /* VARARGS */
229 static void
230 warning(const char *fmt, ...)
231 {
232 	va_list ap;
233 
234 	(void)fprintf(stderr, "%s: WARNING: ", program_name);
235 	va_start(ap, fmt);
236 	(void)vfprintf(stderr, fmt, ap);
237 	va_end(ap);
238 	if (*fmt) {
239 		fmt += strlen(fmt);
240 		if (fmt[-1] != '\n')
241 			(void)fputc('\n', stderr);
242 	}
243 }
244