-Matches IPv4 source address \fIip\fR, which may be specified as an
-IP address or host name (e.g. \fB192.168.1.1\fR or
-\fBwww.example.com\fR). The optional \fInetmask\fR allows restricting a
-match to an IPv4 address prefix. The netmask may be specified as a dotted
-quad (e.g. \fB192.168.1.0/255.255.255.0\fR) or as a CIDR block
+.IQ \fBnw_dst=\fIip\fR[\fB/\fInetmask\fR]
+When \fBdl_type\fR is 0x0800 (possibly via shorthand, e.g. \fBip\fR
+or \fBtcp\fR), matches IPv4 source (or destination) address \fIip\fR,
+which may be specified as an IP address or host name
+(e.g. \fB192.168.1.1\fR or \fBwww.example.com\fR). The optional
+\fInetmask\fR allows restricting a match to an IPv4 address prefix.
+The netmask may be specified as a dotted quad
+(e.g. \fB192.168.1.0/255.255.255.0\fR) or as a CIDR block