Filter multicast on dd-wrt

insmod ebtables
insmod ebtable_filter

iptables -I FORWARD -m pkttype --pkt-type multicast -i br0 -s ip_source -j DROP
iptables -I FORWARD -m pkttype --pkt-type multicast -i br0 -s ip_source2 -j DROP

Cisco recovery password (8xx series)

Work for these Cisco routers:
  

• Cisco 806 Series Router
  
• Cisco 826 Series Router
  
• Cisco 827 Series Router
  
• Cisco 828 Series Router
  
• Cisco 831 Series Router
  
• Cisco 836 Series Router
  
• Cisco 837 Series Router
  
• Cisco 881 Series Router
  

=============================================
Send BREAK after power on the router.
In HyperTerminal CTRL+BREAK
In Minicom CTRL + A + F

C850 series (Board ID: 4-149) platform with 65536 Kbytes of main memory

rommon 1 > confreg 0x2142

You must reset or power cycle for new config to take effect
rommon 2 > reset   (this command will reset the router)
rommon 3 >
System Bootstrap, Version 12.3(8r)YI2, RELEASE SOFTWARE
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 2005 by cisco Systems, Inc.

........................

         --- System Configuration Dialog ---

Would you like to enter the initial configuration dialog? [yes/no]: no


Press RETURN to get started!

Router>
Router>ena
Router#
Router#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#config-register 0x2102
Router(config)#
Router(config)#^Z    (CTRL+Z)

==========================
 If you wish to save old configuration:
Router#copy startup-config running-config
Router#conf t
Router(config)#enable secret cisco
Router(config)#^Z
Router#wr
 [OK]
 ==========================
Router#wr
 [OK]
Router#
Router#reload
Proceed with reload? [confirm]