Add static/custom attribute with ACS Url

[Tom Scavo]

On Wed, Feb 7, 2018 at 1:40 PM, Santu Ghosh <mon.snahasish at gmail.com> wrote:
>
> I have an SP with entityId https://xxx.com/shibboleth-sp.
> More than 4 IdP are connected with my SP. Among them 3 using SP initiated
> and one used IdP initiated authentication. Now the IDP who use IdP initiated
> flow try to execute SP's ACE URL i,e, https://xxx.com/shibboleth-sp in their
> end.

Oops, apparently you typed your entityID twice.

> After executing above mentioned url , user of that Idp are redirected to
> error page. Because when SP received the requested url in ACS location, SP
> is unable to distinguished IDP's identity. As a result they are redirected
> to error page.

The IdP's identity is in the SAML assertion.

> Is it possible to add an custom/static parameter with the ACS URL ?

Have you considered using RelayState? In an SP-initiated flow, the SP
determines the RelayState, but in an IdP-initiated flow, the IdP can
add whatever RelayState value the SP will understand (presumably by
prior agreement).

Tom