react-native-hash

Getting started

$ npm install react-native-hash --save

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compatibility

Criteria	Release Version
Android API < 16	unsupported
16 <= Android API < 21	1.x
Gradle >= 7	>= 2.0.1

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Usage

Constants

HashAlgorithms: Record<string, string>;

HmacAlgorithms: Record<string, string>;

Events: Record<string, string>;

Example

import { CONSTANTS } from 'react-native-hash';

const hashAlgorithm = CONSTANTS.HashAlgorithms.sha256;

const hmacAlgorithm = CONSTANTS.HmacAlgorithms.HmacSHA512;

const EventName = CONSTANTS.Events.onBatchReccieved;

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Cross Platform API

Native hashing is only implemented on Android, however, until I get around writing native modules for other platforms ( or if some kind soul makes a PR), you can use JSHash and JSHmac:

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NOTE

if you are using expo, JSHash and JSHmac should work out of the box, native implementations however, will require you to eject the project.

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Hash Algorithm :

"MD2" | "MD5"| "SHA-1"| "SHA-224" | "SHA-256" | "SHA-384" | "SHA-512"| "keccak"

HMac Algorithm :

"HmacMD5" | "HmacSHA1" | "HmacSHA224" | "HmacSHA256" | "HmacSHA384" | "HmacSHA512"

API:

JSHash(message: string, algorithm: string):Promise<string>;

JSHmac(message: string, secret: string, algorithm: string): Promise<string>;

Example :

import { JSHash, JSHmac, CONSTANTS } from "react-native-hash";

JSHash("message", CONSTANTS.HashAlgorithms.sha256)
  .then(hash => console.log(hash))
  .catch(e => console.log(e));

JSHmac("message", "SecretKey", CONSTANTS.HmacAlgorithms.HmacSHA256)
  .then(hash => console.log(hash))
  .catch(e => console.log(e));

• keccak implementation defaults to 512 and is not tested against all attack vectors.

check out the example for more information.

React Hooks

Following hooks are available:

useHash(
  hashAlgo?: string = "MD5",
  initialMessage?: string = "hello World",
): [
  hashed: string,
  setMessage: (message: string) => Promise<void>,
  setAlgo: (algo: string) => Promise<void>
];

useHmac(
  hmacAlgo?: string = "HmacMD5",
  initialMessage?: string = "hello World",
  initialSecret?: string = "SecretKey",
): [
  hashed: string,
  setMessage: (message: string) => Promise<void>,
  setAlgo: (algo: string) => Promise<void>,
  setSecret: (secret: string) => Promise<void>
];

Usage

const [hashedMessage, setHashAlgo, setHashMessage] = useHash();
const [hmac, setHmacAlgo, setHmacMessage, setHmacSecret] = useHmac();

hashedMessage and hmac will update after a call to one of the setters is resolved.

note that all the setter functions of these two hooks are async and will return a promise.

check out the [example] for more information.

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Android

Hash Algorithm :

"md2" | "md5" | "sha1" | "sha224" | "sha256" | "sha384" | "sha512"

HMAC Algorithm :

"HmacMD5" | "HmacSHA1" | "HmacSHA224" | "HmacSHA256" | "HmacSHA384" | "HmacSHA512" | "PBEwithHmacSHA" "PBEwithHmacSHA1" | "PBEwithHmacSHA224" | "PBEwithHmacSHA256" | "PBEwithHmacSHA384" | "PBEwithHmacSHA512"

API

hashFile(uri: string, algorithm: string): Promise<string>;

hashFilesForFolder(uri: string, algorithm: string, minFileSize: number, maxFileSize: number, extensionFilter: string, batchSize: number, delay: number ):  Promise<{FilesCount:number, isFinalBatch: bool, batchNumber: number, results: Record<string, string>}>;

• pass an empty string "" to the hashFilesForFolder as extensionFilter if you dont want to filter the results.
• if you pass -1 as batchSize, the function will return a promise which resolves into an object with all hashes
• if you pass any number other than -1 to batchSize, instead of returning the results, null will be returned, but when each batch is ready an event will be fired.
• the delay parameter determines how many ms should the native thread waits before sending the next batch.
• check "press to hash Folder with events" and "press to hash Folder" in the example app for more details

hashFilesForFolders(uri: string, algorithm: string, minFileSize: number, maxFileSize: number, extensionFilter: string, batchSize: number, delay: number ):  Promise<{FilesCount:number, isFinalBatch: bool, batchNumber: number, results: Record<string, string>}>;

• behaves the same as the hashFilesForFolder, but reccieves an String array as first argument.

hashUrl(url: string, HTTPMethod: string, headers: Record<string, string>, algorithm: string): Promise<string>;

hashString(message: string, algorithm: string): Promise<string>;

generateHmac(message: string, key: string, algorithm: string): Promise<string>;

Example

import RnHash, { CONSTANTS } from "react-native-hash";

RnHash.hashFile("uri", CONSTANTS.HashAlgorithms.sha256)
  .then(hash => console.log(hash))
  .catch(e => console.log(e));

RNHash.hashFilesForFolders(
  ["uri", "anotherUri"],
  CONSTANTS.HashAlgorithms.sha256,
  0,
  1048576,
  ".mp3",
  -1,
  0
)
  .then(b => setFolderString(JSON.stringify(b)))
  .catch(er => console.log(er));

  RNHash.hashFilesForFolder(
  "uri",
  CONSTANTS.HashAlgorithms.sha256,
  0,
  1048576,
  ".mp3",
  -1,
  0
)
  .then(b => setFolderString(JSON.stringify(b)))
  .catch(er => console.log(er));

RnHash.hashUrl(
  "url",
  "HTTPMethod",
  { "Content-type": "application/json" },
  CONSTANTS.HashAlgorithms.sha256
)
  .then(hash => console.log(hash))
  .catch(e => console.log(e));

RnHash.hashString("message", CONSTANTS.HashAlgorithms.sha256)
  .then(hash => console.log(hash))
  .catch(e => console.log(e));

RNHash.generateHmac("message", "secretKey", CONSTANTS.HmacAlgorithms.HmacSHA512)
  .then(HMAC => console.log(HMAC))
  .catch(er => console.log(er));

check out the example for more information.

Topics

• documentation
• to do
• contribution guide
• code of conduct

Hashing files and urls are only supported on android at this point

Todo

• SHA-3
• other Keccak lengths

Status

	iOS	Android	windows
hash local files	❌	✔️	❌
hash network assets	❌	✔️	❌
hash network responses	❌	✔️	❌
hash bundle assets	❌	❌	❌
hash strings	✔️	✔️	✔️
HMAC	✔️	✔️	✔️

• all PRs are welcome

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Credits

JSHash and JSHMac functions use some Open Source code snippets. You can find the source code of their open source projects along with license information below. We acknowledge and are grateful to these developers for their contributions to open source.

• Project: crypto-es https://github.com/entronad/crypto-es

• License (MIT) https://github.com/entronad/crypto-es/blob/master/LICENSE

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