fix: redirectUri being added a port on windows platform

[Unreal22]

Hi, I'm not sure if this is a issue, or if I'm missing a config, but whenever I try to use this on windows, the Uri gets changed, and in Chrome as web works fine.

final manager = OidcUserManager.lazy(
store: OidcMemoryStore(),
settings: OidcUserManagerSettings(redirectUri: Uri.parse("com.okta.dev-41706738:/callback")),
clientCredentials:const OidcClientAuthentication.clientSecretBasic(clientId: "0oahre9v3cQmMQ3BR5d7",
clientSecret: "cT4PozCQcBYtE1MG_36qjDQGYjdLQeu5tohr0aStjuZo2J96bymtxYJ-kaI8Ce0w",),
discoveryDocumentUri: OidcUtils.getOpenIdConfigWellKnownUri(Uri.parse("https://dev-41706738-admin.okta.com"),),);

Chrome: redirect_uri=com.okta.dev-41706738%3A%2Fcallback (Good one)
Windows: redirect_uri=com.okta.dev-41706738%3A%2F%2F%3A53856%2Fcallback (Changed one)

I'm using the example Git repo, didn't really changed any setting, and I'm using the same example that comes with the package.

Thanks a lot!

[ahmednfwela]

We are using https://datatracker.ietf.org/doc/html/rfc8252 to handle desktop auth

and there are 3 ways to receive the auth response

The redirect url you used suggests you are using the first method "Private-Use URI Scheme Redirection", which is actually less secure.

This is why we only support the third method (Loopback Interface Redirection) as it does not require any custom configuration regarding DNS or messing with domain claims.

our example app contains a sample code on how to configure a cross-platform redirect uri:

oidc/packages/oidc/example/lib/app_state.dart

Lines 45 to 71 in 5a5b31d

	postLogoutRedirectUri: kIsWeb
	? Uri.parse('http://localhost:22433/redirect.html')
	: Platform.isAndroid || Platform.isIOS || Platform.isMacOS
	? Uri.parse('com.bdayadev.oidc.example:/endsessionredirect')
	: Platform.isWindows || Platform.isLinux
	? Uri.parse('http://localhost:0')
	: null,
	redirectUri: kIsWeb
	// this url must be an actual html page.
	// see the file in /web/redirect.html for an example.
	//
	// for debugging in flutter, you must run this app with --web-port 22433
	? Uri.parse('http://localhost:22433/redirect.html')
	: Platform.isIOS || Platform.isMacOS || Platform.isAndroid
	// scheme: reverse domain name notation of your package name.
	// path: anything.
	? Uri.parse('com.bdayadev.oidc.example:/oauth2redirect')
	: Platform.isWindows || Platform.isLinux
	// using port 0 means that we don't care which port is used,
	// and a random unused port will be assigned.
	//
	// this is safer than passing a port yourself.
	//
	// note that you can also pass a path like /redirect,
	// but it's completely optional.
	? Uri.parse('http://localhost:0')
	: Uri(),

[ahmednfwela]

After doing some research around okta provider, it seems that it's a limitation with okta: https://devforum.okta.com/t/loopback-interface-redirection-ephemeral-ports-wildcard-ports-in-localhost-redirect-uri/22197/2