This page provides general information about the S/MIME support in S/Notify
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S/Notify currently supports the following two formats:
PKCS#7
BouncyCastle
Prior to version 3.1, the user key store file had to be in BouncyCastle format.
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S/MIME certificates are sometimes assigned different classes, which are intended to represent the grade of verification of the certificate owner. For example, for a “class 1” S/MIME certificate, only the email address has been verified, while in a “class 2” S/MIME certificate, also the owner’s name and the company or organization has been verified by the issuer. For “class 3”, specific documents are required for the verification , and “class 4” requests a verification in person. Certificate classes are not part of the standard, and were introduced by certification authorities, perhaps for more economical reasons.
In practical use, these classes do not make a difference. Even more, the class is either not part of the certificate, or only in a proprietary way that depends on the issuer. The only differentiation could be made between class 1 and the other classes, but the question remains why “class 1” certificates should be rejected. Therefore, S/Notify does not make a difference between these of S/MIME certificate classes.
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