3e5df37861
The old code implicitly relies on the ASN.1 code returning a \0-prefixed buffer when the buffer length is 0. Change this to verify explicitly that the ASN.1 string has positive length. Reviewed-by: Dr Stephen Henson <steve@openssl.org> (cherry picked from commit 82dc08de54ce443c2a9ac478faffe79e76157795)