+ *
+ * NOTE! It is important that all _public_ data can be verified
+ * with reference to the _private_ data. There exist attacks based
+ * on modifying the public key but leaving the private section
+ * intact.
+ *
+ * With RSA, this is easy: verify that n = p*q, and also verify
+ * that e*d == 1 modulo (p-1)(q-1). With DSA (if we were ever to
+ * support it), we would need to store extra data in the private
+ * section other than just x.