noip.[c1]: New configuration feature for setting local addresses.

[preload-hacks] / noip.1

diff --git a/noip.1 b/noip.1
index 8687958..a79a872 100644 (file)
--- a/noip.1
+++ b/noip.1
@@ -175,6 +175,43 @@ rules are appended on the end.  Currently, the rules in
 are also put at the end (before the
 .B _AFTER
 rules), though this may change later.
+.TP
+.BI "impbind " bind-rule
+Add an entry to the implicit-bind rule list.  When a program attempts to
+.BR connect (2)
+a socket without binding its local address first,
+.B noip
+consults this list to decide on the correct local address to assign.
+Each entry in the list has the form
+.RS
+.IP
+.I address-range
+.IR address | \c
+.B same
+.PP
+The rules are tried in order: if the remote address matches (in the same
+way as in an ACL entry) the address range on the left side of the rule,
+then the socket is bound to the address from the right side; if the
+address on the right is
+.B same
+then the remote address is used.
+.PP
+Three environment variables
+are consulted too:
+.BR NOIP_IMPBIND_BEFORE ,
+.BR NOIP_IMPBIND ,
+and
+.BR NOIP_IMPBIND_AFTER .
+The
+.B _BEFORE
+rules are inserted at the front of the list; the
+.B _AFTER
+rules are appended on the end.  Currently, the rules in
+.B NOIP_IMPBIND
+are also put at the end (before the
+.B _AFTER
+rules), though this may change later.
+.RE
 .PP
 (Aside: An attempt to connect to a remote host may not be a hopeless failure,
 even if a real IP socket is denied: