> From: owner-openssl-us...@openssl.org On Behalf Of jeetendra gangele > Sent: Sunday, 16 December, 2012 22:57
> Actaully I was trying to generate the signature of lenght 56 bytes but > its failing. > When I check the code it said lenght of the sig should not > lessa than 56. > can anybody help me how can I generate the signature of > lenght 56 bytes?. > To be clear: you are talking about the length of the *signature*, not of the data that was signed? If you are using a 224-bit ECDSA keypair, as your previous posts suggest, the signature semantically consists of two numbers each 224 bits or 28 bytes; however, openssl (at least) encodes these numbers in an ASN.1 SEQUENCE with total length 62-64 bytes. If you want to generate such a signature, either use the EVP_Sign* functions to do the usual process for you (hash the bulk data, using a hash you specify whose output size should not be larger than your keysize, then ECDSA-sign the hash) or do the hash yourself and then call ECDSA_sign or one of its variants yourself. ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org
