On Wed, Oct 28, 2020 at 09:46:49AM +0100, Harald Koch wrote: > Hello, > > I’ve been asked to support an optional feature when using S/MIME > signed message transmission for (as they call it) „Algorithm > identifier protection“, which is defined in RFC6211. As I’ve found no > evidence in the headers of openSSL, I’m asking you if this feature is > available or planned. Actually, I’m using the latest openSSL version > 1.1.1 with funtions for PKCS7 signing (PKCS7_sign, > PKCS7_sign_add_signer, SMIME_write_PKCS7). That of course looks like a CMS feature, but I don't see evidence of suppport for it in OpenSSL at this time. -- Viktor.