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--- ./src/knock.c.orig 2005-06-27 07:11:34.000000000 +0200
+++ ./src/knock.c 2011-08-17 13:21:28.000000000 +0200
@@ -1,8 +1,8 @@
/*
* knock.c
- *
+ *
* Copyright (c) 2004-2005 by Judd Vinet <jvinet@zeroflux.org>
- *
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
@@ -15,7 +15,7 @@
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*/
@@ -23,16 +23,20 @@
#include <stdlib.h>
#include <stdarg.h>
#include <netdb.h>
-#include <sys/socket.h>
#include <sys/types.h>
+#include <sys/socket.h>
+#if defined(__FreeBSD__) || defined(__APPLE__)
+#include <netinet/in.h>
+#endif
#include <arpa/inet.h>
#include <unistd.h>
#include <string.h>
+#include <netinet/in.h>
#include <resolv.h>
#include <getopt.h>
#include <fcntl.h>
-static char version[] = "0.5";
+static char version[] = "#VERSION#";
#define PROTO_TCP 1
#define PROTO_UDP 2
@@ -44,6 +48,7 @@
int o_verbose = 0;
int o_udp = 0;
+int o_delay = 0;
int main(int argc, char** argv)
{
@@ -55,12 +60,13 @@
{
{"verbose", no_argument, 0, 'v'},
{"udp", no_argument, 0, 'u'},
+ {"delay", required_argument, 0, 'd'},
{"help", no_argument, 0, 'h'},
{"version", no_argument, 0, 'V'},
{0, 0, 0, 0}
};
- while((opt = getopt_long(argc, argv, "vuhV", opts, &optidx))) {
+ while((opt = getopt_long(argc, argv, "vud:hV", opts, &optidx))) {
if(opt < 0) {
break;
}
@@ -68,6 +74,7 @@
case 0: break;
case 'v': o_verbose = 1; break;
case 'u': o_udp = 1; break;
+ case 'd': o_delay = (int)atoi(optarg); break;
case 'V': ver();
case 'h': /* fallthrough */
default: usage();
@@ -77,6 +84,11 @@
usage();
}
+ if(o_delay < 0) {
+ fprintf(stderr, "error: delay cannot be negative\n");
+ exit(1);
+ }
+
host = gethostbyname(argv[optind++]);
if(host == NULL) {
fprintf(stderr, "Cannot resolve hostname\n");
@@ -98,16 +110,16 @@
} else {
port = atoi(arg);
}
-
+
if(o_udp || proto == PROTO_UDP) {
- sd = socket(PF_INET, SOCK_DGRAM, 0);
+ sd = socket(PF_INET, SOCK_DGRAM, 0);
if(sd == -1) {
fprintf(stderr, "Cannot open socket\n");
exit(1);
}
} else {
int flags;
- sd = socket(PF_INET, SOCK_STREAM, 0);
+ sd = socket(PF_INET, SOCK_STREAM, 0);
if(sd == -1) {
fprintf(stderr, "Cannot open socket\n");
exit(1);
@@ -121,13 +133,13 @@
addr.sin_port = htons(port);
if(o_udp || proto == PROTO_UDP) {
vprint("hitting udp %s:%u\n", inet_ntoa(addr.sin_addr), port);
- connect(sd, (struct sockaddr*)&addr, sizeof(struct sockaddr));
- send(sd, NULL, 0, MSG_DONTWAIT);
+ sendto(sd, "", 1, 0, (struct sockaddr*)&addr, sizeof(addr));
} else {
vprint("hitting tcp %s:%u\n", inet_ntoa(addr.sin_addr), port);
connect(sd, (struct sockaddr*)&addr, sizeof(struct sockaddr));
}
close(sd);
+ usleep(1000*o_delay);
}
return(0);
@@ -148,6 +160,7 @@
printf("usage: knock [options] <host> <port[:proto]> [port[:proto]] ...\n");
printf("options:\n");
printf(" -u, --udp make all ports hits use UDP (default is TCP)\n");
+ printf(" -d, --delay <t> wait <t> milliseconds between port hits\n");
printf(" -v, --verbose be verbose\n");
printf(" -V, --version display version\n");
printf(" -h, --help this help\n");
|
