Macro content length considerations

Information supplied by macros increases the string length of the Location URI header. URI encoding of macro content further increases this string length.

Some client applications (such as WAP browsers on cellular phones) have URI length limitations due to the small memory capacity of the device. If a URI exceeds the length limitation on such a client device, errors can occur and the link will likely fail.

WebSEAL does not impose any length restrictions on the Location URI header. Therefore, when configuring macros for local response redirection, we must carefully consider the possible limitations of client devices that access your site. We can estimate the length of the Location header by determining the fixed lengths of the URI and the TAM_OP values, and factor in expected sizes of any macros used in the query string.

The following table provides information about the possible lengths of the content provided by the macros used for local response redirection:

Macro	Size of Content
AUTHNLEVEL	No more than 10 characters.
HOSTNAME	The length of the HOST header of the corresponding request, or the fully qualified host name of the WebSEAL system if the HOST header is not present.
PROTOCOL	No more than 10 characters.
URL	Length of the request URI.
USERNAME	Maximum length defined by user name length policy for this implementation of WebSEAL.
HTTPHDR{name}	Length of the specified HTTP header.
CREDATTR{name}	Length of the contents for the specified attribute in the user credential.

Parent topic: Macro support for automatic redirection