checkPublicKey(pub); err != nil { return nil, err } else if !fipsApproved { fips140.RecordNonApproved() } k := pub.Size() if len(msg) > k-2*hash.Size()-2 { return nil, ErrMessageTooLong } hash.Reset() hash.Write(label) lHash := hash.Sum(nil) em := make([]byte, k) seed := em[1 : 1+hash.Size()] db := em[1+hash.Size():] copy(db[0:hash.Size()], lHash) db[len(db)-len(msg)-1] = 1 copy(db[len(db)-len(msg):], msg) if err := drbg.ReadWithReaderDeterm(random, seed); err != nil { return nil, err } mgf1XOR(db, mgfHash, seed) mgf1XOR(seed,...