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/* DESC: This script runs a shell command using telnet.
 *       Only the first response line is returned.
 *       Don't forget to enable the telnet server
 *       For special chars in command string use escape: apostrophe = "\x27"
 * Copyright (C) 2014 NetModule AG, Switzerland, rfa
 */
 
string telnet(ip, port, user, password, cmd)
{
 
	if ((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) return NULL;
	if (connect(sock, ip, port) < 0) return NULL;
	try {
		if ((buf = recv(sock)) == NULL || strlen(buf) < 3) throw NULL;
		buf = explode(buf);
		if (buf[0] == "\xff") // is command
		{
			if (buf[1] == "\xfd" && buf[2] == "\d031") { //negotiate
				if (send(sock, "\d255\d251\d031") == -1) throw NULL;
				if (send(sock, "\d255\d250\d031\d000\d080\d000\d024\d255\d240") == -1) throw NULL;
			} else {
				for (i = 0; i < strlen(buf); i++)
					if (buf[i] == "\xfd") buf[i] = "\xfc";
					else if (buf[i] == "\xfb") buf[i] = "\xfd";
				if (send(sock, implode(buf)) == -1) throw NULL;
			}
		}
		if ((buf = recv(sock)) == NULL || strlen(buf) < 1) throw NULL; // user ?
		if (send(sock, strcat(user, "\r\n")) == -1) throw NULL;
		if ((buf = recv(sock)) == NULL || strlen(buf) < 1)throw NULL; // password ?
		if (send(sock, strcat(password, "\r\n")) == -1) throw NULL;
		while((s = select(sock, 1)) > 0 && (buf = recv(sock)) != NULL && strlen(buf) > 0)
			if (s == -1) throw NULL; //ignore all garbage
		if (send(sock, strcat(cmd, "\r\n")) == -1) throw NULL;  //send command
		rbuf ="";
		while((s = select(sock, 1)) > 0 && (buf = recv(sock)) != NULL && strlen(buf) > 0){
			if (s == -1) throw NULL; 
			else rbuf = strcat(rbuf, buf); // collect return
		}
		rbuf = right(rbuf, strlen(rbuf) - strlen(cmd) - 2); //cut cmd
		if (pos = strrchr(rbuf, "\r"))
			rbuf = left(rbuf, pos);
		throw rbuf;
	} catch (ret) {
		close (sock);
		return ret;
	}
}
 
 
printf("date = <%s>\n", telnet("192.168.1.1", 23, "root", "password", "date"));
	// show date
 
printf("uptime = <%s>\n", telnet("192.168.1.1", 23, "root", "password", "uptime | awk \x27{print $8}\x27")); 
	//CPU load. Values 0.00-1.00 0=none, max=1.00(100%)
 
printf("free mem = <%s>\n", telnet("192.168.1.1", 23, "root", "password", "free | grep Total | awk \x27{print $3/$2}\x27"));
    //show free memory Values 0-1 0=none, max=1(100%)
 
printf("ps = <begin>%s<end>\n", telnet("192.168.1.1", 23, "root", "password", "ps"));
	// show processes