Improve email encryption error checking

app/services/pii/cipher.rb

@@ -37,7 +37,13 @@ def decipher(payload)
       cipher.iv = iv(unpacked_payload)
       cipher.auth_tag = tag(unpacked_payload)
       cipher.auth_data = 'PII'
+      try_decipher(unpacked_payload)
+    end
+
+    def try_decipher(unpacked_payload)
       cipher.update(ciphertext(unpacked_payload)) + cipher.final
+    rescue OpenSSL::Cipher::CipherError => err
+      raise EncryptionError, 'failed to decipher payload: ' + err.to_s
     end
 
     def unpack_payload(payload)

app/services/pii/encryptor.rb

@@ -35,7 +35,7 @@ def decrypt_and_test_payload(payload, cek)
       begin
         payload = cipher.decrypt(payload, cek)
       rescue OpenSSL::Cipher::CipherError => err
-        raise EncryptionError, err
+        raise EncryptionError, err.inspect
       end
       raise EncryptionError, 'payload is invalid' unless sane_payload?(payload)
       plaintext, fingerprint = split_into_segments(payload)

app/services/user_access_key.rb

@@ -56,6 +56,7 @@ def encryption_key
   end
 
   def unlock(random_key)
+    raise Pii::EncryptionError, 'Cannot unlock with nil random_key' unless random_key.present?
     self.unlocked = true
     self.random_r = random_key
     hash_e

db/migrate/20161118150205_add_user_email_fingerprint.rb

@@ -8,12 +8,13 @@ def up
     encrypt_user_emails
     change_column_null :users, :email_fingerprint, false
     change_column_null :users, :encrypted_email, false
-    remove_column :users, :email
+    remove_index :users, :email
+    rename_column :users, :email, :email_plain
+    change_column_null :users, :email_plain, true
   end
 
   def down
-    add_column :users, :email, :string
-    add_index :users, :email, unique: true
+    rename_column :users, :email_plain, :email
     decrypt_user_emails
     change_column_null :users, :email, false
     remove_column :users, :email_fingerprint
@@ -31,7 +32,8 @@ def encrypt_user_emails
   def decrypt_user_emails
     User.where(email: nil).each do |user|
       ee = EncryptedEmail.new(user.encrypted_email)
-      user.update!(email: ee.decrypted)
+      escaped = ActiveRecord::Base.connection.quote(ee.decrypted)
+      execute "UPDATE users set email=#{escaped} WHERE id=#{user.id}"
     end
   end
 end

db/schema.rb

@@ -82,6 +82,7 @@
   add_index "profiles", ["user_id"], name: "index_profiles_on_user_id", using: :btree
 
   create_table "users", force: :cascade do |t|
+    t.string   "email_plain",                   limit: 255, default: ""
     t.string   "encrypted_password",            limit: 255, default: ""
     t.string   "reset_password_token",          limit: 255
     t.datetime "reset_password_sent_at"