libxt_sctp.man

.TP
[\fB!\fP] \fB\-\-source\-port\fP,\fB\-\-sport\fP \fIport\fP[\fB:\fP\fIport\fP]
.TP
[\fB!\fP] \fB\-\-destination\-port\fP,\fB\-\-dport\fP \fIport\fP[\fB:\fP\fIport\fP]
.TP
[\fB!\fP] \fB\-\-chunk\-types\fP {\fBall\fP|\fBany\fP|\fBonly\fP} \fIchunktype\fP[\fB:\fP\fIflags\fP] [...]
The flag letter in upper case indicates that the flag is to match if set,
in the lower case indicates to match if unset.

Chunk types: DATA INIT INIT_ACK SACK HEARTBEAT HEARTBEAT_ACK ABORT SHUTDOWN SHUTDOWN_ACK ERROR COOKIE_ECHO COOKIE_ACK ECN_ECNE ECN_CWR SHUTDOWN_COMPLETE ASCONF ASCONF_ACK FORWARD_TSN

chunk type            available flags      
.br
DATA                  I U B E i u b e
.br
ABORT                 T t                 
.br
SHUTDOWN_COMPLETE     T t                 

(lowercase means flag should be "off", uppercase means "on")
.P
Examples:

iptables \-A INPUT \-p sctp \-\-dport 80 \-j DROP

iptables \-A INPUT \-p sctp \-\-chunk\-types any DATA,INIT \-j DROP

iptables \-A INPUT \-p sctp \-\-chunk\-types any DATA:Be \-j ACCEPT