Use a variable time multiplication for the torsion check #657
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As the group order is anyway public, there is no reason to prevent it from leaking to a side channel.
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As the group order is anyway public, there is no reason to prevent it from leaking to a side channel.
On my laptop (i7-10610U) the benchmark of
is_torsion_freeimproves from 34 μs to 24 μs.