0.4.4/experiments/udp_snoop.c

/*
 *  Copyright (C) 2006  Anders Gavare.  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright  
 *     notice, this list of conditions and the following disclaimer in the 
 *     documentation and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 *  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE   
 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 *  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 *  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 *  SUCH DAMAGE.
 *
 *
 *  $Id: udp_snoop.c,v 1.1 2006/09/07 11:44:42 debug Exp $
 *
 *  Dumps UDP packets in hex and ASCII that arrive at a specific port.
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>


void dump_buf(unsigned char *p, ssize_t len)
{
        while (len > 0) {
                ssize_t i, n = len>=16? 16 : len;
                for (i=0; i<n; i++)
                        printf(" %02x", p[i]);
                for (i=n; i<16; i++)
                        printf("   ");
                printf("  ");
                for (i=0; i<n; i++) {
                        if (p[i]>=32 && p[i]<127)
                                printf("%c", p[i]);
                        else
                                printf(".");
                }
                printf("\n");
                p += 16;
                len -= 16;
        }
}


int main(int argc, char *argv[])
{
        struct sockaddr_in si;
        int s;

        if (argc < 2) {
                fprintf(stderr, "usage: %s udp_portnr\n", argv[0]);
                exit(1);
        }

        if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
                perror("socket");
                exit(1);
        }

        memset((char *)&si, sizeof(si), 0);
        si.sin_family = AF_INET;
        si.sin_port = htons(atoi(argv[1]));
        si.sin_addr.s_addr = htonl(INADDR_ANY);
        if (bind(s, (struct sockaddr *)&si, sizeof(si)) < 0) {
                perror("bind");
                exit(1);
        }

        for (;;) {
                unsigned char buf[2048];
                ssize_t r = recv(s, buf, sizeof(buf), 0);

                if (r < 0) {
                        perror("recv");
                        exit(1);
                }

                dump_buf(buf, r);
                printf("\n");
        }

        return 0;
}

1	dpavlin	32	/*
2			* Copyright (C) 2006 Anders Gavare. All rights reserved.
3			*
4			* Redistribution and use in source and binary forms, with or without
5			* modification, are permitted provided that the following conditions are met:
6			*
7			* 1. Redistributions of source code must retain the above copyright
8			* notice, this list of conditions and the following disclaimer.
9			* 2. Redistributions in binary form must reproduce the above copyright
10			* notice, this list of conditions and the following disclaimer in the
11			* documentation and/or other materials provided with the distribution.
12			* 3. The name of the author may not be used to endorse or promote products
13			* derived from this software without specific prior written permission.
14			*
15			* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18			* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25			* SUCH DAMAGE.
26			*
27			*
28			* $Id: udp_snoop.c,v 1.1 2006/09/07 11:44:42 debug Exp $
29			*
30			* Dumps UDP packets in hex and ASCII that arrive at a specific port.
31			*/
32
33			#include <stdio.h>
34			#include <stdlib.h>
35			#include <sys/types.h>
36			#include <sys/socket.h>
37			#include <netinet/in.h>
38
39
40			void dump_buf(unsigned char *p, ssize_t len)
41			{
42			while (len > 0) {
43			ssize_t i, n = len>=16? 16 : len;
44			for (i=0; i<n; i++)
45			printf(" %02x", p[i]);
46			for (i=n; i<16; i++)
47			printf(" ");
48			printf(" ");
49			for (i=0; i<n; i++) {
50			if (p[i]>=32 && p[i]<127)
51			printf("%c", p[i]);
52			else
53			printf(".");
54			}
55			printf("\n");
56			p += 16;
57			len -= 16;
58			}
59			}
60
61
62			int main(int argc, char *argv[])
63			{
64			struct sockaddr_in si;
65			int s;
66
67			if (argc < 2) {
68			fprintf(stderr, "usage: %s udp_portnr\n", argv[0]);
69			exit(1);
70			}
71
72			if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
73			perror("socket");
74			exit(1);
75			}
76
77			memset((char *)&si, sizeof(si), 0);
78			si.sin_family = AF_INET;
79			si.sin_port = htons(atoi(argv[1]));
80			si.sin_addr.s_addr = htonl(INADDR_ANY);
81			if (bind(s, (struct sockaddr *)&si, sizeof(si)) < 0) {
82			perror("bind");
83			exit(1);
84			}
85
86			for (;;) {
87			unsigned char buf[2048];
88			ssize_t r = recv(s, buf, sizeof(buf), 0);
89
90			if (r < 0) {
91			perror("recv");
92			exit(1);
93			}
94
95			dump_buf(buf, r);
96			printf("\n");
97			}
98
99			return 0;
100			}
101