mirror of https://github.com/golang/go.git
dc50683bf7
This change alters the CurveParam methods to upgrade from the generic curve implementation to the specific P224 or P256 implementations when called on the embedded CurveParams. This removes the trap of using elliptic.P224().Params() instead of elliptic.P224(), for example, which results in using the generic implementation instead of the optimized constant time one. For P224 this is done for all of the CurveParams methods, except Params, as the optimized implementation covers all these methods. For P256 this is only done for ScalarMult and ScalarBaseMult, as despite having implementations of addition and doubling they aren't exposed and instead the generic implementation is used. For P256 an additional check that there actually is a specific implementation is added, as unlike the P224 implementation the P256 one is only available on certain platforms. This change takes the simple, fast approach to checking this, it simply compares pointers. This removes the most obvious class of mistakes people make, but still allows edge cases where the embedded CurveParams pointer has been dereferenced (as seen in the unit tests) or when someone has manually constructed their own CurveParams that matches one of the standard curves. A more complex approach could be taken to also address these cases, but it would require directly comparing all of the CurveParam fields which would, in the worst case, require comparing against two standard CurveParam sets in the ScalarMult and ScalarBaseMult paths, which are likely to be the hottest already. Updates #34648 Change-Id: I82d752f979260394632905c15ffe4f65f4ffa376 Reviewed-on: https://go-review.googlesource.com/c/go/+/233939 Trust: Roland Shoemaker <roland@golang.org> Trust: Katie Hockman <katie@golang.org> Run-TryBot: Roland Shoemaker <roland@golang.org> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Filippo Valsorda <filippo@golang.org> Reviewed-by: Katie Hockman <katie@golang.org> |
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| .. | ||
| aes | ||
| cipher | ||
| des | ||
| dsa | ||
| ecdsa | ||
| ed25519 | ||
| elliptic | ||
| hmac | ||
| internal | ||
| md5 | ||
| rand | ||
| rc4 | ||
| rsa | ||
| sha1 | ||
| sha256 | ||
| sha512 | ||
| subtle | ||
| tls | ||
| x509 | ||
| crypto.go | ||
| issue21104_test.go | ||