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https://github.com/wavesplatform/ts-lib-crypto

All algorithm implementations like signature verification and protocol entries like address used in Waves protocol.
https://github.com/wavesplatform/ts-lib-crypto

crypto cryptography signature

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All algorithm implementations like signature verification and protocol entries like address used in Waves protocol.

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# ts-lib-crypto [![npm version](https://badge.fury.io/js/%40waves%2Fts-lib-crypto.svg)](https://www.npmjs.com/package/@waves/ts-lib-crypto)



The waves protocol is a set of rules named consensus by which nodes reach an agreement on the network, and format which nodes use to communicate with each other. It based on several well described hash and crypto algorithms and has predefined set of entries to operate on network. This library contains all algorithm implementations like signature verification and protocol entries like address used in waves protocol. Also it contains utility methods and format converters to help 3rd party developers.



## Agenda

- **[Installation](#installation)**

- **[Import styles](#import-styles)**

- **[Inputs](#inputs)**

- **[Outputs](#outputs)**

 - **[Seed generation](#seed-generation)**

	 - [randomSeed](#randomseed)

	 - [seedWordsList](#seedwordslist)

 - **[Keys and address](#keys-and-address)**

	 - [publicKey](#publickey)

	 - [privateKey](#privatekey)

	 - [keyPair](#keypair)

	 - [address](#address)

 - **[Signatures](#signatures)**

	 - [signBytes](#signbytes)

	 - [verifySignature](#verifySignature)

- **[Hashing](#hashing)**

	 - [blake2b](#blake2b)

	 - [keccak](#keccak)

	 - [sha256](#sha256)

 - **[Random](#random)**

	 - [randomBytes](#randomBytes)

	 - [random](#random)

 - **[Base encoding\decoding](#base-encodingdecoding)**

	 - [base16](#base-encodingdecoding)

	 - [base58](#base-encodingdecoding)

	 - [base64](#base-encodingdecoding)

 - **[Messaging](#messaging)**

	 - [sharedKey](#sharedKey)

	 - [messageEncrypt](#messageEncrypt)

	 - [messageDecrypt](#messageDecrypt)

 - **[Encryption](#encryption)**

	 - [aesEncrypt](#aesEncrypt)

	 - [aesDecrypt](#aesDecrypt)

- **[Seed encryption](#Seed-encryption)**

 - **[Utils](#utils)**

	 - [split](#split)

	 - [concat](#concat)

	 - [stringToBytes](#stringtobytes)

	 - [bytesToString](#bytestostring)

- **[Constants](#constants)**

- **[Interface](#interface)**

- **[More examples](#more-examples)**

## Installation

```

npm install @waves/ts-lib-crypto

```

## Import styles

The is several ways of doing things when using **ts-lib-crypto**.

You can import functions strait-forward:

```ts

import { address } from  '@waves/ts-lib-crypto'

address('my secret seed') // 3PAP3wkgbGjdd1FuBLn9ajXvo6edBMCa115

```

Or you can use a crypto constructor function:

```ts

import { crypto } from  '@waves/ts-lib-crypto'

const { address } = crypto()

address('my secret seed') // 3PAP3wkgbGjdd1FuBLn9ajXvo6edBMCa115

```

The second approach gives you more flexibility, using this approach you are able to embed the **seed** and use all seed-dependant functions without **seed** parameter:

```ts

import { crypto } from  '@waves/ts-lib-crypto'

const { address } = crypto({seed: 'my secret seed'})

address() // 3PAP3wkgbGjdd1FuBLn9ajXvo6edBMCa115

```



## Inputs 

**ts-lib-crypto** is even more flexible. Any function argument that represents binary data or seed could be passed in several ways. Let's take a look on the following example:

```ts

import { address } from  '@waves/ts-lib-crypto'

const  seedString  =  'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

const  seedBytesAsArray  = [117, 110, 99, 108, 101, 32, 112, 117, 115, 104, 32, 104, 117, 109, 97, 110, 32, 98, 117, 115, 32, 101, 99, 104, 111, 32, 100, 114, 97, 115, 116, 105, 99, 32, 103, 97, 114, 100, 101, 110, 32, 106, 111, 107, 101, 32, 115, 97, 110, 100, 32, 119, 97, 114, 102, 97, 114, 101, 32, 115, 101, 110, 116, 101, 110, 99, 101, 32, 102, 111, 115, 115, 105, 108, 32, 116, 105, 116, 108, 101, 32, 99, 111, 108, 111, 114, 32, 99, 111, 109, 98, 105, 110, 101]

const  seedBytesAsUintArray  =  Uint8Array.from(seedBytesAsArray)

address(seedString) // 3P9KR33QyXwfTXv8kKtNGZYtgKk3RXSUk36

address(seedBytesAsArray) // 3P9KR33QyXwfTXv8kKtNGZYtgKk3RXSUk36

address(seedBytesAsUintArray) // 3P9KR33QyXwfTXv8kKtNGZYtgKk3RXSUk36

```

As you can see **seed** parameter is treated the same way for **number[]** or **Uint8Array**.

When you pass binary data is could be represented as  **number[]** or **Uint8Array** or even **base58**:

```ts

import { address, randomSeed, sha256 } from '@waves/ts-lib-crypto'

const seed = randomSeed() // uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine

const addressBase58 = address(seed) // 3P9KR33QyXwfTXv8kKtNGZYtgKk3RXSUk36

sha256(addressBase58) // DMPenguwWdLdZ7tesiZY6grw7mjKU2Dob1cn9Uq9TKfp

```

Here we got **sha256** hash from address bytes represented as **base58** *(3P9KR33QyXwfTXv8kKtNGZYtgKk3RXSUk36)*. 

Be aware that **sha256** value is not based on "*3P9KR33QyXwfTXv8kKtNGZYtgKk3RXSUk36*" string itself, this value was treated as a **binary data** and **base58Decode** was applied.



## Outputs

As you've noticed from the previous section *address()* output is **base58** string like:

```ts

// 3PAP3wkgbGjdd1FuBLn9ajXvo6edBMCa115

```

 By default functions from the following list output **base58** string as a result,

 no matter what import-style you choose:

```

keyPair

publicKey

privateKey

address

sharedKey

signBytes

```



If you prefer **binary** output, you can alter this behaviour and make those functions to return **UInt8Array** instead.



When using inline import style:

```ts

// You can use [/bytes] module when importing functions to set output to UInt8Array

import { address } from  '@waves/ts-lib-crypto/bytes'

address('uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine')

// => Uint8Array [1,87,55,118,79,89,6,115,207,200,130,220,32,33,101,69,108,108,53,48,167,127,203,18,143,121]

```

When using crypto constructor function:

```ts

import { crypto } from  '@waves/ts-lib-crypto'

const { address } = crypto({ output: 'Bytes' })

address('uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine')

// => Uint8Array [1,87,55,118,79,89,6,115,207,200,130,220,32,33,101,69,108,108,53,48,167,127,203,18,143,121]

```



## Seed generation



The seed is a set of words or bytes that private and public keys are generated from. The usual Waves seed looks like:

```

uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine

```

There are couple ways to generate seed: 

```ts

const handWrittenSeedString = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

const handWrittenSeedBytes = [117, 110, 99, 108, 101, 32, 112, 117, 115, 104, 32, 104, 117, 109, 97, 110, 32, 98, 117, 115, 32, 101, 99, 104, 111, 32, 100, 114, 97, 115, 116, 105, 99, 32, 103, 97, 114, 100, 101, 110, 32, 106, 111, 107, 101, 32, 115, 97, 110, 100, 32, 119, 97, 114, 102, 97, 114, 101, 32, 115, 101, 110, 116, 101, 110, 99, 101, 32, 102, 111, 115, 115, 105, 108, 32, 116, 105, 116, 108, 101, 32, 99, 111, 108, 111, 114, 32, 99, 111, 109, 98, 105, 110, 101]

```

Or if you need seed with nonce:

```ts

import { seedWithNonce, randomSeed, address } from '@waves/ts-lib-crypto'



const nonce = 1

const seedphrase = randomSeed() // uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine

const seed = seedWithNonce(seedphrase, nonce)



//Now you can use seed as usual

address(seed)

```

Seed could be any **string** or **number[]** or **Uint8Array** or **ISeedWithNonce**.



There is also a way to generate seed-phrase using **ts-lib-crypto** described in the next section.



### randomSeed

```ts

import { randomSeed } from '@waves/ts-lib-crypto'



randomSeed() //uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine

```

You can also specify seed-phrase size:

```ts

randomSeed(3) //uncle push human

```

The default seed size is 15 words.



### seedWordsList

If you want to get all the valid seed words that official waves-client generates seed-phrase from, use **seedWordsList** the 2048 word array.

```ts

import { seedWordsList } from '@waves/ts-lib-crypto'

console.log(seedWordsList) // [ 'abandon','ability','able', ... 2045 more items ]

```

## Keys and address



### publicKey

You could get public key either from raw seed-phrase or seed with nonce:

```ts

import { publicKey, seedWithNonce } from '@waves/ts-lib-crypto'

const seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

publicKey(seed) // 4KxUVD9NtyRJjU3BCvPgJSttoJX7cb3DMdDTNucLN121

publicKey(seedWithNonce(seed, 0)) // 4KxUVD9NtyRJjU3BCvPgJSttoJX7cb3DMdDTNucLN121

```

Or even from private key, it's usefull in some cases:

```ts

import { publicKey, privateKey, seedWithNonce } from '@waves/ts-lib-crypto'

const seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

const pk = privateKey(seed)

publicKey({ privateKey: pk }) // 4KxUVD9NtyRJjU3BCvPgJSttoJX7cb3DMdDTNucLN121

```



### privateKey

Same with private key:

```ts

import { privateKey, seedWithNonce } from '@waves/ts-lib-crypto'

const  seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

privateKey(seed)

privateKey(seedWithNonce(seed, 99))

```

### keyPair

You could also obtain a keyPair:

```ts

import { keyPair } from '@waves/ts-lib-crypto'

const  seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

keyPair(seed)

// => { 

//      publicKey:  '4KxUVD9NtyRJjU3BCvPgJSttoJX7cb3DMdDTNucLN121',

//      privateKey: '6zFSymZAoaua3gtJPbAUwM584tRETdKYdEG9BeEnZaGW'

//    }

```

### address

You can create an address for *Mainnet*:

```ts

import { address } from '@waves/ts-lib-crypto'

const  seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

address(seed) // 3P9KR33QyXwfTXv8kKtNGZYtgKk3RXSUk36

```

or *Testnet*:

```ts

address(seed, 'T') // 3MwJc5iX7QQGq5ciVFdNK7B5KSEGbUCVxDw

```

alternatively You could use **TEST_NET_CHAIN_ID** constant instead of **T** literal like this:

```ts

import { address, TEST_NET_CHAIN_ID } from '@waves/ts-lib-crypto'

const  seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

address(seed, TEST_NET_CHAIN_ID) // 3MwJc5iX7QQGq5ciVFdNK7B5KSEGbUCVxDw

```

There are several more useful constants, you can check them in [\[constants\]](/#constants) section.

## Signatures

#### signBytes

To sign arbitrary bytes or usually transaction bytes you should use the **signBytes** function.

Here is sign with seed example:

```ts

import { signBytes } from '@waves/ts-lib-crypto'

const bytes = [117, 110, 99, 108, 101]

const seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

signBytes(seed, bytes) // 5ZpULwrnUYoxQZcw26km6tgGbj1y23ywYB4A9bLCpax6PUdrhkCmmoLBP6C1G5yiMJ7drqN9jNxPym6f8vrPsWnm

```

Also you can use private key to sign bytes:

```ts

import { signBytes, privateKey } from '@waves/ts-lib-crypto'

const bytes = [117, 110, 99, 108, 101]

const seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

const key = privateKey(seed)

signBytes({ privateKey: key }, bytes)

```

Remember that you can use **base58** strings when it's about binary data, so you can represent bytes as **base58** too:

```ts

signBytes({ privateKey:  key }, 'Fk1sjwdPSwZ4bPwvpCGPH6')

```

You can learn more about it in the [outputs](#outputs) section.

#### verifySignature

Verifying signature is a way to proof what particular bytes was signed with a particular private key or seed which correspond to public key that we are checking against:

```ts

import { signBytes, verifySignature, keyPair } from '@waves/ts-lib-crypto'

//Signature roundtrip

const bytes = [117, 110, 99, 108, 101]

const seed = 'uncle push human bus echo drastic garden joke sand warfare sentence fossil title color combine'

const keys = keyPair(seed)

const signature = signBytes(keys, bytes)

verifySignature(keys.publicKey, bytes, signature) // true

```

## Hashing

There are three hashing algorithms available in **ts-lib-crypto**.

#### blake2b

```ts

import { blake2b } from '@waves/ts-lib-crypto'

const bytesArray = [117, 110, 99, 108, 101]

const bytesUint = Uint8Array.from([117, 110, 99, 108, 101])

const bytesBase58 = 'EFRr9cp'

blake2b(bytesArray)  // 9DqBU9wZAR85PyrUSJpwaU9DggM8veyMxRMvFe1q6atu

blake2b(bytesUint)   // 9DqBU9wZAR85PyrUSJpwaU9DggM8veyMxRMvFe1q6atu

blake2b(bytesBase58) // 9DqBU9wZAR85PyrUSJpwaU9DggM8veyMxRMvFe1q6atu



```

#### keccak

```ts

import { keccak } from '@waves/ts-lib-crypto'

const bytesArray = [117, 110, 99, 108, 101]

const bytesUint = Uint8Array.from([117, 110, 99, 108, 101])

const bytesBase58 = 'EFRr9cp'

keccak(bytesArray)  // 5cqz9N2PPjDkSBSwga8AttKzQEHfn8aQ95rcZZmabLA7

keccak(bytesUint)   // 5cqz9N2PPjDkSBSwga8AttKzQEHfn8aQ95rcZZmabLA7

keccak(bytesBase58) // 5cqz9N2PPjDkSBSwga8AttKzQEHfn8aQ95rcZZmabLA7

```

#### sha256

```ts

import { sha256 } from '@waves/ts-lib-crypto'

const bytesArray = [117, 110, 99, 108, 101]

const bytesUint = Uint8Array.from([117, 110, 99, 108, 101])

const bytesBase58 = 'EFRr9cp'

sha256(bytesArray)  // 4JPydqbhxhZF7kpuGA2tJWkXDmevJYfig45gqdV1UF9E

sha256(bytesUint)   // 4JPydqbhxhZF7kpuGA2tJWkXDmevJYfig45gqdV1UF9E

sha256(bytesBase58) // 4JPydqbhxhZF7kpuGA2tJWkXDmevJYfig45gqdV1UF9E

```

## Random

There is several ways to get random values in **ts-lib-crypto**.

To get an **Uint8Array** of random values simply use:

#### randomBytes

```ts

import { randomBytes } from '@waves/ts-lib-crypto'

randomBytes(3) // Uint8Array [ 120, 46, 179 ]             

```

If you want more control over the values format you could use:

#### random

```ts

import { random } from '@waves/ts-lib-crypto'



const length = 3     

random(length, 'Array8')       // [ 19, 172, 130 ]   

random(length, 'Array16')      // [ 61736, 48261, 38395 ] 

random(length, 'Array32')      // [ 406628961, 307686833, 2604847943 ]       

random(length, 'Buffer')       //        

random(length, 'Uint8Array')   // Uint8Array [ 137, 85, 212 ]   

random(length, 'Uint16Array')  // Uint16Array [ 35881, 51653, 55967 ]  

random(length, 'Uint32Array')  // Uint32Array [ 698646076, 2957331816, 2073997581 ]    

```

## Base encoding\decoding



```ts

import { base16Encode, base16Decode, base58Encode, base58Decode, base64Encode, base64Decode, randomBytes } from '@waves/ts-lib-crypto'



const bytes = randomBytes(32)



// Base16 same as Hex

const base16String = base16Encode(bytes) // 2059ec5d9ed640b75722ec6a2ff76890e523ea4624887549db761d678ba8f899

const bytesFromBase16 = base16Decode(base16String)



// Base58

const base58String = base58Encode(bytes) // 3BHaM9Q5HhUobQ5oZAqjdkE9HRpmqMx4XLq3GXTMD5tU

const bytesFromBase58 = base58Decode(base58String)



// Base64

const base64String = base64Encode(bytes) // IFnsXZ7WQLdXIuxqL/dokOUj6kYkiHVJ23YdZ4uo+Jk=

const bytesFromBase64 = base64Decode(base64String)

```

## Messaging

These methods implement waves messaging protocol 

- sharedKey 

- messageDecrypt

- messageEncrypt

```typescript

import { sharedKey, messageEncrypt, messageDecrypt, keyPair } from '@waves/ts-lib-crypto'



const bobKeyPair = keyPair('Bob')

const aliceKeyPair = keyPair('Alice')

const msg = 'hello world'



// Alice derives shared key and encrypts message

const sharedKeyA = sharedKey(aliceKeyPair.privateKey, bobKeyPair.publicKey, 'waves') 

const encrypted = messageEncrypt(sharedKeyA, msg)



// Bob decrypts message derives shared key and decrypts message

const sharedKeyB = sharedKey(aliceKeyPair.privateKey, bobKeyPair.publicKey, 'waves') 

const decrypted = messageDecrypt(sharedKeyB, encrypted)

```

## Encryption

This is low level functionality where you have to generate key and iv yourself 

#### aesEncrypt

Encrypt bytes using AES algorithm. 

```typescript

import { aesEncrypt, randomBytes } from '@waves/ts-lib-crypto'



const data = Uint8Arraty.from([1,2,3])

const mode =  'CBC' // Possible modes are 'CBC' | 'CFB' | 'CTR' | 'OFB' | 'ECB' | 'GCM'



const key = randomBytes(32)

const iv = randomBytes(32)



const encrypted = aesEncrypt(data, key, mode, iv)



```

#### aesDecrypt

Decrypt bytes using AES algorithm

```typescript

const decrypted = aesDecrypt(encrypted, key, mode, iv)

```



## Seed encryption

These functions implements seed encryption protocol used in DexClient and WavesKeeper

```typescript

import { encryptSeed, decryptSeed } from '@waves/ts-lib-crypto'



const seed = 'some secret seed phrase i use'

const encrypted = encryptSeed(seed, 'secure password')

const decrypted = decryptSeed(encryptSeed, 'secure password')



```

## Utils

Utility functions designed to help 3rd party developers working with js binary types like Uint8Array and Buffer.

#### split

You can use split for splitting bytes to sub arrays.

```ts

import { split, randomBytes } from '@waves/ts-lib-crypto'

const bytes = randomBytes(2 + 3 + 4 + 10)

split(bytes, 2, 3, 4)

// [ 

//   Uint8Array [195, 206],

//   Uint8Array [ 10, 208, 171 ],

//   Uint8Array [ 36, 18, 254, 205 ],

//   Uint8Array [ 244, 232, 55, 11, 113, 47, 80, 194, 170, 216 ]

// ]

```

Alternatively, you can use array deconstruction syntax:

```ts

const [a, b, c, rest] = split(bytes, 2, 3, 4)

// a = Uint8Array [195, 206],

// b = Uint8Array [ 10, 208, 171 ],

// c = Uint8Array [ 36, 18, 254, 205 ],

// rest = Uint8Array [ 244, 232, 55, 11, 113, 47, 80, 194, 170, 216 ]

```

#### concat

Concat is the opposite and pretty self-explanatory:

```ts

import { concat, randomBytes } from '@waves/ts-lib-crypto'

const bytesA = randomBytes(2)

const bytesB = randomBytes(2)

concat(bytesA, bytesB) // Uint8Array [ 36, 18, 254, 205 ]

```

#### stringToBytes

```ts

import { stringToBytes } from '@waves/ts-lib-crypto'

stringToBytes('Waves!') // Uint8Array [ 87, 97, 118, 101, 115, 33 ]

```

#### bytesToString

```ts

import { bytesToString } from '@waves/ts-lib-crypto'

bytesToString([ 87, 97, 118, 101, 115, 33 ]) // Waves!

```

## Constants

There is several useful constants declared at **ts-lib-crypto**:

```ts

const PUBLIC_KEY_LENGTH = 32

const PRIVATE_KEY_LENGTH = 32

const SIGNATURE_LENGTH = 64

const ADDRESS_LENGTH = 26



const MAIN_NET_CHAIN_ID = 87 // W

const TEST_NET_CHAIN_ID = 84 // T

```

## Interface 

The full **IWavesCrypto** interface can be found on the [project`s github](https://github.com/wavesplatform/ts-lib-crypto) in [interface.ts](https://github.com/wavesplatform/ts-lib-crypto/blob/master/src/crypto/interface.ts).

```ts

  //Seeds, keys and addresses

  seedWithNonce: (seed: TSeed, nonce: number) => INonceSeed

  keyPair: (seed: TSeed) => TKeyPair

  publicKey: (seed: TSeed) => TBytesOrBase58

  privateKey: (seed: TSeed) => TBytesOrBase58

  address: (seedOrPublicKey: TSeed | TPublicKey, chainId?: TChainId) => TBytesOrBase58



  //Signature

  signBytes: (seedOrPrivateKey: TSeed | TPrivateKey, bytes: TBinaryIn, random?: TBinaryIn) => TDesiredOut

  //Hashing 

  blake2b: (input: TBinaryIn) => TBytes

  keccak: (input: TBinaryIn) => TBytes

  sha256: (input: TBinaryIn) => TBytes



  //Base encoding\decoding

  base64Encode: (input: TBinaryIn) => TBase64

  base64Decode: (input: TBase64) => TBytes //throws (invalid input)

  base58Encode: (input: TBinaryIn) => TBase58

  base58Decode: (input: TBase58) => TBytes //throws (invalid input)

  base16Encode: (input: TBinaryIn) => TBase16

  base16Decode: (input: TBase16) => TBytes //throws (invalid input)



  //Utils

  stringToBytes: (input: string) => TBytes

  bytesToString: (input: TBinaryIn) => string

  split: (binary: TBinaryIn, ...sizes: number[]) => TBytes[]

  concat: (...binaries: TBinaryIn[]) => TBytes



  //Random

  random(count: number, type: T): TRandomTypesMap[T]

  randomBytes: (size: number) => TBytes

  randomSeed: (wordsCount?: number) => string



  //Verification

  verifySignature: (publicKey: TBinaryIn, bytes: TBinaryIn, signature: TBinaryIn) => boolean

  verifyPublicKey: (publicKey: TBinaryIn) => boolean

  verifyAddress: (address: TBinaryIn, optional?: { chainId?: TChainId, publicKey?: TBinaryIn }) => boolean



  //Messaging

  sharedKey: (privateKeyFrom: TBinaryIn, publicKeyTo: TBinaryIn, prefix: TRawStringIn) => TBytesOrBase58

  messageDecrypt: (sharedKey: TBinaryIn, encryptedMessage: TBinaryIn) => string

  messageEncrypt: (sharedKey: TBinaryIn, message: TRawStringIn) => TBytes



  //Encryption

  aesEncrypt: (data: TRawStringIn, secret: TBinaryIn, mode?: AESMode, iv?: TBinaryIn) => TBytes

  aesDecrypt: (encryptedData: TBinaryIn, secret: TBinaryIn, mode?: AESMode, iv?: TBinaryIn) => TBytes

```

## More examples

Every example used in this document and many more can be found on the [project`s github](https://github.com/wavesplatform/ts-lib-crypto) inside [examples](https://github.com/wavesplatform/ts-lib-crypto/tree/master/examples) folder.