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RE: S/MIME v3.2 IDs key size text
This sounds reasonable. I replace the following sentence in 3851bis:
A receiving agent SHOULD be able to verify signatures with keys of any size
over 512 bits.
A receiving agent SHOULD be able to verify signatures with keys up to 16384
>[mailto:owner-ietf-smime@xxxxxxxxxxxx] On Behalf Of Russ Housley
>Sent: Wednesday, March 19, 2008 4:48 PM
>To: Turner, Sean P.; ietf-smime@xxxxxxx
>Subject: Re: S/MIME v3.2 IDs key size text
>>A receiving agent SHOULD be able to verify signatures with
>keys of any
>>size over 512 bits.
>This is asking for denial of service attack. What if someone
>sends a certificate that contains a 64Kbit value claiming to
>be a public key and a blob of random bits claiming to be a
>signature? The amount of time to check the signature (and
>probably find that it is not valid) is onerous.
>Today, I cannot imagine someone making use of a public key
>larger than 8192 bits. Double that it you want to be very