+--------+            +----------+                +--------+
| Origin |            | Attacker |                | Client |
+---+----+            +----+-----+                +---+----+
    |                      |                          |
    +--- TokenChallenge -->|                          |
    |                      +-- (reflect challenge) -->|
    |                      |<-------- Token ----------+
    |<-- (reflect token) --+                          |
    |                      |                          |