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/* |
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* Copyright (C) 2006 Anders Gavare. All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* 3. The name of the author may not be used to endorse or promote products |
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* derived from this software without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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* |
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* |
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* $Id: udp_snoop.c,v 1.1 2006/09/07 11:44:42 debug Exp $ |
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* |
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* Dumps UDP packets in hex and ASCII that arrive at a specific port. |
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*/ |
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|
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <netinet/in.h> |
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|
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|
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void dump_buf(unsigned char *p, ssize_t len) |
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{ |
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while (len > 0) { |
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ssize_t i, n = len>=16? 16 : len; |
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for (i=0; i<n; i++) |
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printf(" %02x", p[i]); |
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for (i=n; i<16; i++) |
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printf(" "); |
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printf(" "); |
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for (i=0; i<n; i++) { |
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if (p[i]>=32 && p[i]<127) |
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printf("%c", p[i]); |
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else |
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printf("."); |
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} |
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printf("\n"); |
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p += 16; |
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len -= 16; |
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} |
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} |
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|
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|
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int main(int argc, char *argv[]) |
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{ |
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struct sockaddr_in si; |
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int s; |
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|
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if (argc < 2) { |
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fprintf(stderr, "usage: %s udp_portnr\n", argv[0]); |
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exit(1); |
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} |
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|
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if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { |
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perror("socket"); |
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exit(1); |
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} |
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|
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memset((char *)&si, sizeof(si), 0); |
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si.sin_family = AF_INET; |
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si.sin_port = htons(atoi(argv[1])); |
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si.sin_addr.s_addr = htonl(INADDR_ANY); |
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if (bind(s, (struct sockaddr *)&si, sizeof(si)) < 0) { |
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perror("bind"); |
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exit(1); |
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} |
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|
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for (;;) { |
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unsigned char buf[2048]; |
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ssize_t r = recv(s, buf, sizeof(buf), 0); |
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|
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if (r < 0) { |
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perror("recv"); |
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exit(1); |
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} |
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|
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dump_buf(buf, r); |
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printf("\n"); |
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} |
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|
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return 0; |
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} |
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|