Added public key validation.

app/models/user.rb

@@ -22,6 +22,8 @@ class User < ActiveRecord::Base
   validates :email, uniqueness: {case_sensitive: false}, format: {with: /\A.+@(.+\..{2,}|\[(IPv6)?[0-9a-f:.]+\])\z/i, message: "That doesn't look like an email address."}
   validates :ign, uniqueness: {case_sensitive: false}, format: {with: /\A[a-z\d_]+\z/i, message: "Username is invalid (a-z, 0-9, _)."}
 
+  validates :public_key, format: {with: /\A(-----BEGIN PGP PUBLIC KEY BLOCK-----((.|\n)*?)-----END PGP PUBLIC KEY BLOCK-----)?\z/i, message: "That doesn't look like a PGP formatted public key."}
+
   has_many :blogposts
   has_many :comments