Updated Blind signature specification (markdown)

Blind-signature-specification.md

@@ -9,6 +9,11 @@ Blind signatures use the following primitives which need to be saved into a file
 - the first byte is 0x02 or 0x03 (which determines which of the two Y coordinates it uses, the difference is that one is even and one is odd. Other bits are ignored by Bitmessage
 - the next 32 bytes are the X coordinate (which is a bignum)
 
+**Signature chain (100 bytes per level)**:
+- Begins with the CA pubkey (35 bytes)
+- on the next levels the intermediary pubkey (35B) and a signature of that pubkey signed by the parent pubkey (65B)
+- and on the last level, the signature of the message signed by the parent pubkey (65B)
+
 **Private key (32B)**: private key is a 256 bit bignum
 
 **Public key (35B)**: public key is two bytes of parameters followed by an EC Point as described above