Edit /etc/sysconfig/SuSEfirewall2:
#do not open ssh ports here
FW_SERVICES_EXT_TCP=""
FW_CONFIGURATIONS_EXT=""
#add this rule
FW_SERVICES_ACCEPT_EXT="0.0.0.0/0,tcp,22,,hitcount=3,blockseconds=60,recentname=ssh"
#Restart firewall:
rcSuSEfirewall2 restart
Now attacker will just have three attempts to break in.