Ultimately, you cannot prevent it; as long as the user has control of their machine, they can "spoof" anything they want. You can, however, make it more difficult/inconvenient for them.
For example, encode the DER form of your CA key directly into your executable, then call d2i_xxx to get the public key, then use that to verify the cert. /r$ ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List [EMAIL PROTECTED] Automated List Manager [EMAIL PROTECTED]