2 "sfa-input" specifies the subset of the requestor context that this match needs to see. It is specified as an xpath expression.
3 For this simple match, we just need to look at sfa-input.
5 "rule" specifies an xpath/xquery expression that evaluates the match. In this case, we just check if the requestor's HRN is the same
6 as the one matched by this rule.
11 <context select="//sfa//user/hrn"/>
15 <help>HRN of the user requesting resouces</help>
16 <operand>HRN</operand>
19 <processor filename="hrn.xsl"/>