lbcd/btcec
Conner Fromknecht 069ec701df
btcec/pubkey: normalize sqrt(x^3) before checking parity
This commit fixes an issue introduced in the recent #1429, where
the output of SqrtVal is not normalized before using IsOdd() to compare
with the expected parity of the y-coordinate. The IsOdd() is only
guaranteed to work if the value has been denormalized, so a denormalized
sqrt >= p would report the opposite parity. We fix this by normalizing
both after compute sqrt(x^3) and when negating the root as directed by
the ybit.
2019-10-10 18:07:37 -07:00
..
bench_test.go btcec: benchmark ParsePubKey for compressed keys 2019-10-02 15:31:23 -07:00
btcec.go btcec/btcec: deprecate QPlus1Div4() in favor of Q() 2019-10-02 18:22:17 -07:00
btcec_test.go btcec: remove obsolete test 2018-05-15 20:47:29 -07:00
ciphering.go Bump up copyright. Reflect recent update. (#699) 2016-05-22 23:22:42 -05:00
ciphering_test.go btcec: Consolidate tests into the btcec package. 2016-10-19 00:55:23 -05:00
doc.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
example_test.go chainhash: Abstract hash logic to new package. (#729) 2016-08-08 14:04:33 -05:00
field.go btcec/pubkey: optimize decompressPoint using fieldVals 2019-10-02 18:21:59 -07:00
field_test.go btcec/pubkey: optimize decompressPoint using fieldVals 2019-10-02 18:21:59 -07:00
genprecomps.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
gensecp256k1.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
precompute.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
privkey.go Change copyright date for code that was updated this year(2016). 2016-01-07 09:01:51 -07:00
privkey_test.go btcec: Consolidate tests into the btcec package. 2016-10-19 00:55:23 -05:00
pubkey.go btcec/pubkey: normalize sqrt(x^3) before checking parity 2019-10-10 18:07:37 -07:00
pubkey_test.go btcec: add new IsCompressedPubKey function 2017-08-13 23:17:40 -05:00
README.md multi: Update markdown files for GFM changes. 2017-05-25 12:06:16 -05:00
secp256k1.go btcec: Regenerate and update precomputed data. 2017-08-18 12:53:28 -05:00
signature.go btcec: correct the comment of recoverKeyFromSignature 2019-09-25 17:28:57 -07:00
signature_test.go btcec/signature: fix DoS bug with signature parsing 2018-09-20 09:26:45 -07:00

btcec

Build Status ISC License GoDoc

Package btcec implements elliptic curve cryptography needed for working with Bitcoin (secp256k1 only for now). It is designed so that it may be used with the standard crypto/ecdsa packages provided with go. A comprehensive suite of test is provided to ensure proper functionality. Package btcec was originally based on work from ThePiachu which is licensed under the same terms as Go, but it has signficantly diverged since then. The btcsuite developers original is licensed under the liberal ISC license.

Although this package was primarily written for btcd, it has intentionally been designed so it can be used as a standalone package for any projects needing to use secp256k1 elliptic curve cryptography.

Installation and Updating

$ go get -u github.com/btcsuite/btcd/btcec

Examples

  • Sign Message
    Demonstrates signing a message with a secp256k1 private key that is first parsed form raw bytes and serializing the generated signature.

  • Verify Signature
    Demonstrates verifying a secp256k1 signature against a public key that is first parsed from raw bytes. The signature is also parsed from raw bytes.

  • Encryption Demonstrates encrypting a message for a public key that is first parsed from raw bytes, then decrypting it using the corresponding private key.

  • Decryption Demonstrates decrypting a message using a private key that is first parsed from raw bytes.

GPG Verification Key

All official release tags are signed by Conformal so users can ensure the code has not been tampered with and is coming from the btcsuite developers. To verify the signature perform the following:

  • Download the public key from the Conformal website at https://opensource.conformal.com/GIT-GPG-KEY-conformal.txt

  • Import the public key into your GPG keyring:

    gpg --import GIT-GPG-KEY-conformal.txt
    
  • Verify the release tag with the following command where TAG_NAME is a placeholder for the specific tag:

    git tag -v TAG_NAME
    

License

Package btcec is licensed under the copyfree ISC License except for btcec.go and btcec_test.go which is under the same license as Go.