| # bcrypt.js | |
| Optimized bcrypt in JavaScript with zero dependencies, with TypeScript support. Compatible to the C++ | |
| [bcrypt](https://npmjs.org/package/bcrypt) binding on Node.js and also working in the browser. | |
| [](https://github.com/dcodeIO/bcrypt.js/actions/workflows/test.yml) [](https://github.com/dcodeIO/bcrypt.js/actions/workflows/publish.yml) [](https://www.npmjs.com/package/bcryptjs) | |
| ## Security considerations | |
| Besides incorporating a salt to protect against rainbow table attacks, bcrypt is an adaptive function: over time, the | |
| iteration count can be increased to make it slower, so it remains resistant to brute-force search attacks even with | |
| increasing computation power. ([see](http://en.wikipedia.org/wiki/Bcrypt)) | |
| While bcrypt.js is compatible to the C++ bcrypt binding, it is written in pure JavaScript and thus slower ([about 30%](https://github.com/dcodeIO/bcrypt.js/wiki/Benchmark)), effectively reducing the number of iterations that can be | |
| processed in an equal time span. | |
| The maximum input length is 72 bytes (note that UTF-8 encoded characters use up to 4 bytes) and the length of generated | |
| hashes is 60 characters. Note that maximum input length is not implicitly checked by the library for compatibility with | |
| the C++ binding on Node.js, but should be checked with `bcrypt.truncates(password)` where necessary. | |
| ## Usage | |
| The package exports an ECMAScript module with an UMD fallback. | |
| ``` | |
| $> npm install bcryptjs | |
| ``` | |
| ```ts | |
| import bcrypt from "bcryptjs"; | |
| ``` | |
| ### Usage with a CDN | |
| - From GitHub via [jsDelivr](https://www.jsdelivr.com):<br /> | |
| `https://cdn.jsdelivr.net/gh/dcodeIO/bcrypt.js@TAG/index.js` (ESM) | |
| - From npm via [jsDelivr](https://www.jsdelivr.com):<br /> | |
| `https://cdn.jsdelivr.net/npm/bcryptjs@VERSION/index.js` (ESM)<br /> | |
| `https://cdn.jsdelivr.net/npm/bcryptjs@VERSION/umd/index.js` (UMD) | |
| - From npm via [unpkg](https://unpkg.com):<br /> | |
| `https://unpkg.com/bcryptjs@VERSION/index.js` (ESM)<br /> | |
| `https://unpkg.com/bcryptjs@VERSION/umd/index.js` (UMD) | |
| Replace `TAG` respectively `VERSION` with a [specific version](https://github.com/dcodeIO/bcrypt.js/releases) or omit it (not recommended in production) to use latest. | |
| When using the ESM variant in a browser, the `crypto` import needs to be stubbed out, for example using an [import map](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script/type/importmap). Bundlers should omit it automatically. | |
| ### Usage - Sync | |
| To hash a password: | |
| ```ts | |
| const salt = bcrypt.genSaltSync(10); | |
| const hash = bcrypt.hashSync("B4c0/\/", salt); | |
| // Store hash in your password DB | |
| ``` | |
| To check a password: | |
| ```ts | |
| // Load hash from your password DB | |
| bcrypt.compareSync("B4c0/\/", hash); // true | |
| bcrypt.compareSync("not_bacon", hash); // false | |
| ``` | |
| Auto-gen a salt and hash: | |
| ```ts | |
| const hash = bcrypt.hashSync("bacon", 10); | |
| ``` | |
| ### Usage - Async | |
| To hash a password: | |
| ```ts | |
| const salt = await bcrypt.genSalt(10); | |
| const hash = await bcrypt.hash("B4c0/\/", salt); | |
| // Store hash in your password DB | |
| ``` | |
| ```ts | |
| bcrypt.genSalt(10, (err, salt) => { | |
| bcrypt.hash("B4c0/\/", salt, function (err, hash) { | |
| // Store hash in your password DB | |
| }); | |
| }); | |
| ``` | |
| To check a password: | |
| ```ts | |
| // Load hash from your password DB | |
| await bcrypt.compare("B4c0/\/", hash); // true | |
| await bcrypt.compare("not_bacon", hash); // false | |
| ``` | |
| ```ts | |
| // Load hash from your password DB | |
| bcrypt.compare("B4c0/\/", hash, (err, res) => { | |
| // res === true | |
| }); | |
| bcrypt.compare("not_bacon", hash, (err, res) => { | |
| // res === false | |
| }); | |
| ``` | |
| Auto-gen a salt and hash: | |
| ```ts | |
| await bcrypt.hash("B4c0/\/", 10); | |
| // Store hash in your password DB | |
| ``` | |
| ```ts | |
| bcrypt.hash("B4c0/\/", 10, (err, hash) => { | |
| // Store hash in your password DB | |
| }); | |
| ``` | |
| **Note:** Under the hood, asynchronous APIs split an operation into small chunks. After the completion of a chunk, the execution of the next chunk is placed on the back of the [JS event queue](https://developer.mozilla.org/en/docs/Web/JavaScript/EventLoop), efficiently yielding for other computation to execute. | |
| ### Usage - Command Line | |
| ``` | |
| Usage: bcrypt <input> [rounds|salt] | |
| ``` | |
| ## API | |
| ### Callback types | |
| - **Callback<`T`>**: `(err: Error | null, result?: T) => void`<br /> | |
| Called with an error on failure or a value of type `T` upon success. | |
| - **ProgressCallback**: `(percentage: number) => void`<br /> | |
| Called with the percentage of rounds completed (0.0 - 1.0), maximally once per `MAX_EXECUTION_TIME = 100` ms. | |
| - **RandomFallback**: `(length: number) => number[]`<br /> | |
| Called to obtain random bytes when both [Web Crypto API](http://www.w3.org/TR/WebCryptoAPI/) and Node.js | |
| [crypto](http://nodejs.org/api/crypto.html) are not available. | |
| ### Functions | |
| - bcrypt.**genSaltSync**(rounds?: `number`): `string`<br /> | |
| Synchronously generates a salt. Number of rounds defaults to 10 when omitted. | |
| - bcrypt.**genSalt**(rounds?: `number`): `Promise<string>`<br /> | |
| Asynchronously generates a salt. Number of rounds defaults to 10 when omitted. | |
| - bcrypt.**genSalt**([rounds: `number`, ]callback: `Callback<string>`): `void`<br /> | |
| Asynchronously generates a salt. Number of rounds defaults to 10 when omitted. | |
| - bcrypt.**truncates**(password: `string`): `boolean`<br /> | |
| Tests if a password will be truncated when hashed, that is its length is greater than 72 bytes when converted to UTF-8. | |
| - bcrypt.**hashSync**(password: `string`, salt?: `number | string`): `string` | |
| Synchronously generates a hash for the given password. Number of rounds defaults to 10 when omitted. | |
| - bcrypt.**hash**(password: `string`, salt: `number | string`): `Promise<string>`<br /> | |
| Asynchronously generates a hash for the given password. | |
| - bcrypt.**hash**(password: `string`, salt: `number | string`, callback: `Callback<string>`, progressCallback?: `ProgressCallback`): `void`<br /> | |
| Asynchronously generates a hash for the given password. | |
| - bcrypt.**compareSync**(password: `string`, hash: `string`): `boolean`<br /> | |
| Synchronously tests a password against a hash. | |
| - bcrypt.**compare**(password: `string`, hash: `string`): `Promise<boolean>`<br /> | |
| Asynchronously compares a password against a hash. | |
| - bcrypt.**compare**(password: `string`, hash: `string`, callback: `Callback<boolean>`, progressCallback?: `ProgressCallback`)<br /> | |
| Asynchronously compares a password against a hash. | |
| - bcrypt.**getRounds**(hash: `string`): `number`<br /> | |
| Gets the number of rounds used to encrypt the specified hash. | |
| - bcrypt.**getSalt**(hash: `string`): `string`<br /> | |
| Gets the salt portion from a hash. Does not validate the hash. | |
| - bcrypt.**setRandomFallback**(random: `RandomFallback`): `void`<br /> | |
| Sets the pseudo random number generator to use as a fallback if neither [Web Crypto API](http://www.w3.org/TR/WebCryptoAPI/) nor Node.js [crypto](http://nodejs.org/api/crypto.html) are available. Please note: It is highly important that the PRNG used is cryptographically secure and that it is seeded properly! | |
| ## Building | |
| Building the UMD fallback: | |
| ``` | |
| $> npm run build | |
| ``` | |
| Running the [tests](./tests): | |
| ``` | |
| $> npm test | |
| ``` | |
| ## Credits | |
| Based on work started by Shane Girish at [bcrypt-nodejs](https://github.com/shaneGirish/bcrypt-nodejs), which is itself | |
| based on [javascript-bcrypt](http://code.google.com/p/javascript-bcrypt/) (New BSD-licensed). | |