key.rb in bitcoin-ruby-0.0.12

- old
+ new

@@ -5,10 +5,14 @@
   # Elliptic Curve key as used in bitcoin.
   class Key
 
     attr_reader :key
 
+    MIN_PRIV_KEY_MOD_ORDER = 0x01
+    # Order of secp256k1's generator minus 1.
+    MAX_PRIV_KEY_MOD_ORDER = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364140
+
     # Generate a new keypair.
     #  Bitcoin::Key.generate
     def self.generate(opts={compressed: true})
       k = new(nil, nil, opts); k.generate; k
     end
@@ -253,9 +257,11 @@
       set_pub(Bitcoin::OpenSSL_EC.regenerate_key(priv)[1], @pubkey_compressed)
     end
 
     # Set +priv+ as the new private key (converting from hex).
     def set_priv(priv)
+      value = priv.to_i(16)
+      raise 'private key is not on curve' unless MIN_PRIV_KEY_MOD_ORDER <= value && value <= MAX_PRIV_KEY_MOD_ORDER
       @key.private_key = OpenSSL::BN.from_hex(priv)
     end
 
     # Set +pub+ as the new public key (converting from hex).
     def set_pub(pub, compressed = nil)