# How to generate key pair

Private key on GXChain is a Random BigInteger, and the public key is the product of G and PrivateKey on ECC (elliptic curve cryptography). The token is a point on the elliptic curve. Like most blockchain systems, GXChain's public-private key pair is based on the secp256k1 curve. The relationship between private key p and public key P is expressed as:

P = secp256k1.G.multiply(p)

# BIP39 and mnemonic

BIP39 is short for Bitcoin Improvement Proposal No.0039. The content of the proposal is to define a scheme for generating a private key through mnemonics, and to solve the problem that the private key is difficult to record by text. The method is to obtain a series of random words in the dictionary. Come to the seed generated as a private key. GXChain's mnemonic is composed of 16 random words, examples are as follows:

truvat amyrin cuss tulare redcoat reckla arratel cladose deedbox receipt overwin quasi kan bout joe rompish

# Private Key

As described at the beginning of the article, the private key of GXChain is essentially a BigInteger, and the relationship between the mnemonic (m) and the private key (p) is:

p = sha256(sha512(m+' '+i));

Tips

Where i is the sequence, by changing i, one mnemonic can generate multiple private keys

In order to prevent accidental omission during replication, the private key consists of the version number (fixed value 0x80), private key p itself, checksum (2 times sha256 encoded private key), expressed as

p' = Base58(Buffer.concat([0x80, p, sha256(sha256(p)).slice(0,4)]))

In order to facilitate copying and expression in shorter text, we encode the above three parts by Base58, which is called Wallet Import Format (WIF). An example is as follows:

5JrWo7xtBXSQybihT9wmepNxaNyxMyETPiUSAVMdEBEmotwocS4

# Public Key

As mentioned at the beginning of the article, the relationship between the public key and the private key is

P = secp256k1.G.multiply(p)

Similarly, in order to facilitate replication and prevent replication omissions, the checksum calculated by the core asset identifier GXC and calculated by RIPEMD160 is used as a suffix, and the public key and the checksum part are encoded in the form of Base58, expressed as:

P' = GXC+Base58(Buffer.concat([P,ripemd160(p).slice(4)]))

eg.

GXC8jfLPQcaNEzz1HGL5pHPzM7ZPuDKaCLiiXxTkU7ec63WDoJQiL

# References

# Reference implementations

Python:

Go:

Elixir:

Objective-C:

Haskell:

.NET C# (PCL):

.NET C# (PCL):

JavaScript:

Ruby:

Rust:

Swift:

C++:

C (with Python/Java/Javascript bindings):