* before verification. If the `hash' is NULL, then the hash algorithm
* to be used is retrieved from the signature. If it isn't present in the
* signature the verification is done as is without hashing. The `rng'
* before verification. If the `hash' is NULL, then the hash algorithm
* to be used is retrieved from the signature. If it isn't present in the
* signature the verification is done as is without hashing. The `rng'
- * is usually not needed, however some algorithms might need it so it is
- * wise to provide it. If this returns NULL the asynchronous operation
- * cannot be controlled.
+ * is usually not needed and may be NULL. If this returns NULL the
+ * asynchronous operation cannot be controlled.