Revert a regression in DSS key generation #310
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A change in f0017b8 caused a random regression in DSS key signing due to moving the padding on the integers generated by DSA from the left to the right. So, for example, if signing the test case string "jerri blank", the random number might be generated as: k=703745698612177278239572677252380378525350342103 If so, the signature parts will be: r=184615963997659989901526712385095827509599268253 s=2682547683721156713440053885014828604195555319 Note the s being shorter. Prior to f0017b8, s would be right-padded with zeros: s=268254768372115671344005388501482860419555531900 After, it would be left-padded: s=002682547683721156713440053885014828604195555319 When converting back to a long, that loses the padding. This change restores the behaviour. Fixes paramiko#308
bitprophet
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Apr 14, 2014
Revert a regression in DSS key generation
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A change in f0017b8 caused a random regression in DSS key signing
due to moving the padding on the integers generated by DSA from the left
to the right.
So, for example, if signing the test case string "jerri blank", the
random number might be generated as:
k=703745698612177278239572677252380378525350342103
If so, the signature parts will be:
r=184615963997659989901526712385095827509599268253
s=2682547683721156713440053885014828604195555319
Note the s being shorter.
Prior to f0017b8, s would be right-padded with zeros:
s=268254768372115671344005388501482860419555531900
After, it would be left-padded:
s=002682547683721156713440053885014828604195555319
When converting back to a long, that loses the padding. This change
restores the behaviour.
Fixes #308