You certainly can't take a block of arbitrary data the same size as the modulus, as it might represent a number which is larger than the modulus (if enough high order bits are set).
I dont think you can directly use CBC or similar schemes, as the input to the encryption is shorter than the output (so you would end up trying to do XOR with different sized objects). You would need to modify CBC to handle this - you really need to define a special chaining scheme. And ECB would be bad because you could shuffle blocks around (because they are not chained together) - actually ECB is bad for many reasons and should only be used in special cases.
Yes, it could be done that way. But nobody does this (and PGP probably does not support it).
RSA and other similar algorithms can only 'encrypt' things which are quite a lot shorter than the key length (and they use some kind of padding scheme). So you would have to define some kind of encoding scheme which splits the source into blocks to 'encrypt' them (and with some kind of chaining scheme so that the bad guys could not take blocks from different messages and rearrange them). As far as I know, there is no standard for this with widespread support.
And how do you think PGP signs something?
It takes a checksum of it (hopefully avoiding md5) and passes that through the signature algorithm (RSA or something similar). So you can't avoid the checksum (hash function) by using PGP.
No.
It doesn't stop anybody filing for a patent.
It doesn't stop a patent being granted.
It does allow anyone with sufficient funds to challenge the patent.
Why not urge governments to require all documents to be delivered in either ODF or OOXML? And by OOXML I dont mean 'microsoft office 2007 format'. Any document ought to be validated by an (open-source) validation program. So no proprietary extensions are allowed - just what is written in the standard.
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You certainly can't take a block of arbitrary data the same size as the modulus, as it might represent a number which is larger than the modulus (if enough high order bits are set). I dont think you can directly use CBC or similar schemes, as the input to the encryption is shorter than the output (so you would end up trying to do XOR with different sized objects). You would need to modify CBC to handle this - you really need to define a special chaining scheme. And ECB would be bad because you could shuffle blocks around (because they are not chained together) - actually ECB is bad for many reasons and should only be used in special cases.
Yes, it could be done that way. But nobody does this (and PGP probably does not support it). RSA and other similar algorithms can only 'encrypt' things which are quite a lot shorter than the key length (and they use some kind of padding scheme). So you would have to define some kind of encoding scheme which splits the source into blocks to 'encrypt' them (and with some kind of chaining scheme so that the bad guys could not take blocks from different messages and rearrange them). As far as I know, there is no standard for this with widespread support.
And how do you think PGP signs something? It takes a checksum of it (hopefully avoiding md5) and passes that through the signature algorithm (RSA or something similar). So you can't avoid the checksum (hash function) by using PGP.
Burn it to get energy? Bury it in disused coal mines?
No. It doesn't stop anybody filing for a patent. It doesn't stop a patent being granted. It does allow anyone with sufficient funds to challenge the patent.
Why not urge governments to require all documents to be delivered in either ODF or OOXML? And by OOXML I dont mean 'microsoft office 2007 format'. Any document ought to be validated by an (open-source) validation program. So no proprietary extensions are allowed - just what is written in the standard.