IBM Tivoli Access Manager for e-business: WebSEAL Administration ...

Modifying
absolute
URLs
with
script
filtering
WebSEAL
requires
additional
configuration
to
handle
the
processing
of
absolute
URLs
embedded
in
scripts.
Web
scripting
languages
include
Javascripts,
VBscripts,
ASP,
JSP,
ActiveX,
and
others.
The
WebSEAL
configuration
file
contains
a
parameter
that
enables
or
disables
filtering
of
embedded
absolute
URLs:
[script-filtering]
script-filter
=
no
Script-filtering
is
disabled
by
default.
To
enable
script
filtering,
set:
script-filter
=
yes
The
script-filter
mechanism
expects
absolute
URLs
with
a
standard
scheme,
server,
resource
format:
http://server/resource
The
script-filter
mechanism
replaces
the
scheme
and
server
portions
of
the
link
with
the
correct
junction
information
(as
a
relative
pathname):
/junction-name/resource
This
filtering
solution
parses
a
script
embedded
in
HTML
code
and
therefore
requires
additional
processing
overhead
that
can
negatively
impact
performance.
Limit
your
use
of
the
script-filter
parameter
only
to
junctions
that
require
support
for
filtering
of
embedded
absolute
URLs.
The
following
diagram
illustrates
this
absolute
URL
filtering
solution:
You
can
optionally
configure
WebSEAL
to
rewrite
the
original
absolute
URL
as
an
absolute
URL,
instead
of
a
relative
URL
(default).
To
enable
this
functionality,
set
the
rewrite-absolute-with-absolute
parameter
in
the
[script-filtering]
stanza
of
the
WebSEAL
configuration
file
to
equal
″yes″:
[script-filtering]
rewrite-absolute-with-absolute
=
yes
With
this
functionality
enabled,
the
example
URL
in
the
diagram
above
would
appear
as
follows:
http://webseal-hostname/jctA/abc.html
Filtering
changes
the
Content-Length
header
Normally,
the
Content-Length
header
in
a
response
from
a
back-end
server
indicates
the
size
of
the
content
being
returned.
When
WebSEAL
filters
URLs
and
Client
WebSEAL
Application Server
(serves Javascript)
Script containing
absolute URL:
http://server/abc.html
Client receives:
/jctA/abc.html
Request Request
Client makes request
using link:
/jctA/abc.html
abc.html
successfully located
script-filtering=yes
WebSEAL reformats link to:
/jctA/abc.html
1
2
3
/jctA
Figure
13.
Filtering
absolute
URLs
290
IBM
Tivoli
Access
Manager
for
e-business:
WebSEAL
Administration
Guide