mirror of
https://gogs.blitter.com/RLabs/xs
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caac02a77b
2/2 Added vendor/ dir to lock down dependent pkg versions.
The author of git.schwanenlied.me/yawning/{chacha20,newhope,kyber}.git has copied
their repos to gitlab.com/yawning/ but some imports of chacha20 from newhope still
inconsistently refer to git.schwanenlied.me/, breaking build.
Licenses for chacha20 also changed from CC0 to AGPL, which may or may not be an
issue. Until the two aforementioned issues are resolved, locking to last-good
versions is probably the best way forward for now.
To build with vendored deps, use make VENDOR=1 clean all
32 lines
807 B
Go
32 lines
807 B
Go
// poly.go - NewHope reductions.
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//
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// To the extent possible under law, Yawning Angel has waived all copyright
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// and related or neighboring rights to newhope, using the Creative
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// Commons "CC0" public domain dedication. See LICENSE or
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// <http://creativecommons.org/publicdomain/zero/1.0/> for full details.
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package newhope
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// Incomplete-reduction routines; for details on allowed input ranges
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// and produced output ranges, see the description in the paper:
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// https://cryptojedi.org/papers/#newhope
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const (
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qinv = 12287 // -inverse_mod(p,2^18)
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rlog = 18
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)
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func montgomeryReduce(a uint32) uint16 {
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u := a * qinv
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u &= ((1 << rlog) - 1)
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u *= paramQ
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a = (a + u) >> 18
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return uint16(a)
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}
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func barrettReduce(a uint16) uint16 {
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u := (uint32(a) * 5) >> 16
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u *= paramQ
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a -= uint16(u)
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return a
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}
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