go-ethereum

Commit Graph

Author	SHA1	Message	Date
Luke Champine	462ddce5b2	crypto/ecies: improve concatKDF (#20836 ) This removes a bunch of weird code around the counter overflow check in concatKDF and makes it actually work for different hash output sizes. The overflow check worked as follows: concatKDF applies the hash function N times, where N is roundup(kdLen, hashsize) / hashsize. N should not overflow 32 bits because that would lead to a repetition in the KDF output. A couple issues with the overflow check: - It used the hash.BlockSize, which is wrong because the block size is about the input of the hash function. Luckily, all standard hash functions have a block size that's greater than the output size, so concatKDF didn't crash, it just generated too much key material. - The check used big.Int to compare against 2^32-1. - The calculation could still overflow before reaching the check. The new code in concatKDF doesn't check for overflow. Instead, there is a new check on ECIESParams which ensures that params.KeyLen is < 512. This removes any possibility of overflow. There are a couple of miscellaneous improvements bundled in with this change: - The key buffer is pre-allocated instead of appending the hash output to an initially empty slice. - The code that uses concatKDF to derive keys is now shared between Encrypt and Decrypt. - There was a redundant invocation of IsOnCurve in Decrypt. This is now removed because elliptic.Unmarshal already checks whether the input is a valid curve point since Go 1.5. Co-authored-by: Felix Lange <fjl@twurst.com>	5 years ago
Egon Elbre	10ce8b0e3c	crypto: fix megacheck warnings (#14917 ) * crypto: fix megacheck warnings * crypto/ecies: remove ASN.1 support	7 years ago
Felix Lange	9b0af51386	crypto: add btcec fallback for sign/recover without cgo (#3680 ) * vendor: add github.com/btcsuite/btcd/btcec * crypto: add btcec fallback for sign/recover without cgo This commit adds a non-cgo fallback implementation of secp256k1 operations. * crypto, core/vm: remove wrappers for sha256, ripemd160	8 years ago
Gustav Simonsson	c8ad64f33c	crypto, crypto/ecies, crypto/secp256k1: libsecp256k1 scalar mult thanks to Felix Lange (fjl) for help with design & impl	9 years ago
Felix Lange	ea54283b30	all: update license information	9 years ago

6 Commits (84d8eb2ca8ae1bcf073658a417276cba66af2e09)