From 9b0af513867fad4aeb3516e4711dd0ea4f5bc90c Mon Sep 17 00:00:00 2001
From: Felix Lange <fjl@users.noreply.github.com>
Date: Sat, 18 Feb 2017 09:24:12 +0100
Subject: 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
---
 vendor/github.com/btcsuite/btcd/btcec/README.md | 74 +++++++++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100644 vendor/github.com/btcsuite/btcd/btcec/README.md

(limited to 'vendor/github.com/btcsuite/btcd/btcec/README.md')

diff --git a/vendor/github.com/btcsuite/btcd/btcec/README.md b/vendor/github.com/btcsuite/btcd/btcec/README.md
new file mode 100644
index 000000000..5875dfc91
--- /dev/null
+++ b/vendor/github.com/btcsuite/btcd/btcec/README.md
@@ -0,0 +1,74 @@
+btcec
+=====
+
+[![Build Status](https://travis-ci.org/btcsuite/btcd.png?branch=master)]
+(https://travis-ci.org/btcsuite/btcec) [![ISC License]
+(http://img.shields.io/badge/license-ISC-blue.svg)](http://copyfree.org)
+[![GoDoc](https://godoc.org/github.com/btcsuite/btcd/btcec?status.png)]
+(http://godoc.org/github.com/btcsuite/btcd/btcec)
+
+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
+
+```bash
+$ go get -u github.com/btcsuite/btcd/btcec
+```
+
+## Examples
+
+* [Sign Message]
+  (http://godoc.org/github.com/btcsuite/btcd/btcec#example-package--SignMessage)  
+  Demonstrates signing a message with a secp256k1 private key that is first
+  parsed form raw bytes and serializing the generated signature.
+
+* [Verify Signature]
+  (http://godoc.org/github.com/btcsuite/btcd/btcec#example-package--VerifySignature)  
+  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]
+  (http://godoc.org/github.com/btcsuite/btcd/btcec#example-package--EncryptMessage)
+  Demonstrates encrypting a message for a public key that is first parsed from
+  raw bytes, then decrypting it using the corresponding private key.
+
+* [Decryption]
+  (http://godoc.org/github.com/btcsuite/btcd/btcec#example-package--DecryptMessage)
+  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:
+  ```bash
+  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:
+  ```bash
+  git tag -v TAG_NAME
+  ```
+
+## License
+
+Package btcec is licensed under the [copyfree](http://copyfree.org) ISC License
+except for btcec.go and btcec_test.go which is under the same license as Go.
+
-- 
cgit