The technique is the "block type 02" padding technique
specified in PKCS #1. This technique was specifically adopted for use
by PEM to handle the multiple recipients issue.
I checked in the son-of-RFC1115 Internet Draft, but could only find a
indirect hint about using "block type 02" for this purpose, and could
not find a hint at all that one should use _different random patterns
for each recipient_ in these type 02 blocks to prevent chinese remainder
attacks for the case where the public exponent is 3. I believe this should
be further clarified in the son-of-RFC1115.
Markus Mueller
FIDES Informatik
Abteilung IB2
Badenerstrasse 172
CH-8004 Zuerich
Switzerland
SWITCH/ARPA/BITNET : mueller(_at_)komsys(_dot_)tik(_dot_)ethz(_dot_)ch
UUCP :
mueller%komsys(_dot_)tik(_dot_)ethz(_dot_)ch(_at_)chx400(_dot_)uucp
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