> Problem Description: > When a digest has been signed and a response is produced, > the current version of openssl will not verify the contents > correctly if the certificate used to sign the digest has expired. > Solution: > When verifying the response/token, the time at which the digest was > signed is used by setting the time in the X509 store by using > X509_STORE_CTX_set_time. > I have attached a patch file to fix this. > Brad
I don't know enough about the specifics of this use in this case to comment intelligently on whether this is good or bad. However, I do know enough to urge caution before this patch is accepted. There are a list of possible issues. Again, I don't know whether each of these issues actually applies to this situation, but they must be all ruled out by someone competent before this patch is accepted: 1) The certificate may have been revoked before this signature was made. Yet the certificate may not be on the current revocation list because expired certificates may be dropped from that list. 2) Are we trusting the expired certificate to tell us when the signature was made? What if the certificate is not very secure and so was only made valid for, say, 6 months because it was expected to take more than 6 months to break it. Now that somoene has compromised it 2 years later, we don't want them to create a signature that claims it was made during the validity interval. I believe current practice is only to accept a signature with an expired certificate if the signature is timestamped by a trusted certificate that has not itself expired. That way, we know by a certificate that is still valid that the signature was in fact made during the validity interval for that signing certificate. Again, this is outside my field of expertise. I just want to make sure this isn't adopted (by the distribution or by readers of this list) before it's security is evaluated. DS ______________________________________________________________________ OpenSSL Project http://www.openssl.org Development Mailing List openssl-dev@openssl.org Automated List Manager [EMAIL PROTECTED]
