[prev in list] [next in list] [prev in thread] [next in thread] 

List:       gcrypt-devel
Subject:    Generate ECDH shared key - NIST P256
From:       Mandar M Apte via Gcrypt-devel <gcrypt-devel () gnupg ! org>
Date:       2020-06-22 12:44:31
Message-ID: 518964648.31228.1592829871223.JavaMail.administrator () n7 ! nabble ! com
[Download RAW message or body]

Hi all, 
   I am trying to generate ECC shared secret key using Libgcrypt 1.8.5. Based on \
documentation of Libgcrypt, I used gcry_pk_genkey() to generate public-private key \
pair on server and client. The S-Expression I used is "(genkey(ecdh(curve \
NIST-P256)(use-fips186)))" to generate public-private key pair based on ECC NIST P256 \
curve.   Now I need to generate shared secret key (ECDH agreement) using Local \
private key and remote public key. I see that, there is no single function like \
"ECDH_compute_key()" in openssl, to generate secret shared key.

After browsing lot of websites, white paper etc, I figured out that gcry_pk_encrypt() \
is suppose to be used to generate shared secret. But when I tried to use that \
function, it yielded me different shared secret. On client side, I am using client's \
private key and server's public key and on server side I am using Server's private \
key and client's public key.

Can anyone help me in this please, to generate shared secret key using Libgcrypt \
1.8.5 version ? Any help is highly appreciated.

Thank you in advance.
Best Regards,
Mandar

_____________________________________
Sent from http://gnupg.10057.n7.nabble.com


_______________________________________________
Gcrypt-devel mailing list
Gcrypt-devel@gnupg.org
http://lists.gnupg.org/mailman/listinfo/gcrypt-devel


[prev in list] [next in list] [prev in thread] [next in thread]