ADFS Strategy for Überauth.

In ADFS Server setup a new Client using Powershell:

Add-AdfsClient -Name "OAUTH2 Client" -ClientId "unique-custom-client-id" -RedirectUri "http://localhost:4000/auth/adfs/callback"
Add-ADFSRelyingPartyTrust -Name "OAUTH2 Client" -Identifier "http://localhost:4000/auth/adfs"
Set-AdfsRelyingPartyTrust -IssuanceAuthorizationRulesFile "TransformRules.txt"

In TransformRules.txt put the following:

@RuleTemplate = "LdapClaims"
@RuleName = "User Details"
c:[Type == "http://schemas.microsoft.com/ws/2008/06/identity/claims/windowsaccountname", Issuer == "AD AUTHORITY"]
=> issue(store = "Active Directory", types = ("http://schemas.microsoft.com/ws/2008/06/identity/claims/windowsaccountname", "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/givenname", "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/surname", "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress", "groups", "userPrincipalName"), query = ";sAMAccountName,givenName,sn,mail,tokenGroups,userPrincipalName;{0}", param = c.Value);

Add 'adfs_url', 'adfs_metadata_url', 'client_id', 'resource_identifier' and optionally adfs_handler to your configuration:

config :ueberauth, Ueberauth.Strategy.ADFS,
  adfs_url: "https://adfs.url",
  adfs_handler: MyApp.ADFSHandler, # Use custom handler to extract information from the token claims
  client_id: "the_client",
  resource_identifier: "the_resource_id"

An example custom ADFS handler

defmodule MyApp.ADFSHandler do
  use Ueberauth.Strategy.ADFS.Handler

  def credentials(conn) do
    token = conn.private.adfs_token

    %Credentials{
      expires: token.claims["exp"] != nil,
      expires_at: token.claims["exp"],
      scopes: token.claims["aud"],
      token: token.token
    }
  end

  @doc false
  def info(conn) do
    user = conn.private.adfs_user

    %Info{
      nickname: user["winaccountname"],
      name: "#{user["given_name"]} #{user["family_name"]}",
      email: user["email"],
      first_name: user["given_name"],
      last_name: user["family_name"]
    }
  end

  @doc false
  def extra(conn) do
    user = conn.private.adfs_user

    %Extra{
      raw_info: %{
        token: conn.private[:adfs_token],
        id_token: conn.private[:adfs_id_token],
        user: user,
        groups: user["groups"]
      }
    }
  end
end