RSA

import { RSA } from "https://deno.land/x/god_crypto/rsa.ts";

Overview

• Usage
• Reference
  • Import key with parseKey
  • constructor
  • encrypt
  • decrypt
  • sign
  • unsign
• Examples
  • Sign and Verify with RS256 for JWT

---

Usage

import { RSA } from "https://deno.land/x/god_crypto/rsa.ts";

const publicKey = RSA.parseKey(Deno.readTextFileSync("./public.pem"));
const cipher = await new RSA(publicKey).encrypt("Hello World");
console.log(ciper.base64());

const privateKey = RSA.parseKey(Deno.readTextFileSync("./private.pem"));
const plain = await new RSA(privateKey).decrypt(cipher);
console.log(plain.toString());

---

References

Import with parseKey

RSA.parseKey(key: string);

Example:

const pem = `-----BEGIN PUBLIC KEY-----
  MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAnzyis1ZjfNB0bBgKFMSv
  vkTtwlvBsaJq7S5wA+kzeVOVpVWwkWdVha4s38XM/pa/yr47av7+z3VTmvDRyAHc
  aT92whREFpLv9cj5lTeJSibyr/Mrm/YtjCZVWgaOYIhwrXwKLqPr/11inWsAkfIy
  tvHWTxZYEcXLgAXFuUuaS3uF9gEiNQwzGTU1v0FqkqTBr4B8nW3HCN47XUu0t8Y0
  e+lf4s4OxQawWD79J9/5d3Ry0vbV3Am1FtGJiJvOwRsIfVChDpYStTcHTCMqtvWb
  V6L11BWkpzGXSW4Hv43qa+GSYOD2QU68Mb59oSk2OB+BtOLpJofmbGEGgvmwyCI9
  MwIDAQAB
  -----END PUBLIC KEY-----`;

const publicKey = RSA.parseKey(pem);

---

constructor

new RSA(key)

Take either public or private key generated by RSA.parseKey.

---

encrypt

const rsa = new RSA(key);
await rsa.encrypt(message, options);

Parameters	Default	Description
message		Message to encrypt. Take Uint8Array or string
options
>> options.padding	oaep	Padding. Support two padding: pkcs1 and oaep
>> options.hash	sha256	Hash algorithm used in mask generation function. Support sha1 and sha256 Applied only oaep padding mode

Example

const rsa = new RSA(publicKey);
await rsa.encrypt("Hello World");
await rsa.encrypt("Hello World", { hash: "sha1" });
await rsa.encrypt("Hello World", { padding: "pkcs1" });

(await rsa.encrypt("Hello World")).hex();
(await rsa.encrypt("Hello World")).base64();

---

decrypt

const rsa = new RSA(key);
await rsa.encrypt(cipher, options);

Parameters	Default	Description
cipher		Uint8Array Cipher text to decrypt
options
>> options.padding	oaep	Padding. Support two padding: pkcs1 and oaep
>> options.hash	sha256	Hash algorithm used in mask generation function. Support sha1 and sha256 Applied only oaep padding mode

Example

const cipher = await new RSA(publicKey).encrypt("Hello World");
const plain = await new RSA(privateKey).decrypt(cipher);

---

Examples

Sign and Verify with RS256 for JWT

import { RSA }    from "https://deno.land/x/god_crypto/rsa.ts";
import { encode}  from "https://deno.land/x/god_crypto/encode.ts";

const jwt =
  "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiw" +
  "iYWRtaW4iOnRydWUsImlhdCI6MTUxNjIzOTAyMn0.POstGetfAytaZS82wHcjoTyoqhMyxXiWdR7Nn7A29DNSl0E" +
  "iXLdwJ6xC6AfgZWF1bOsS_TuYI3OG85AmiExREkrS6tDfTQ2B3WXlrr-wp5AokiRbz3_oB4OxG-W9KcEEbDRcZc0" +
  "nH3L7LzYptiy1PtAylQGxHTWZXtGz4ht0bAecBgmpdgXMguEIcoqPJ1n3pIWk_dUZegpqx0Lka21H6XxUTxiy8Oc" +
  "aarA8zdnPUnV6AmNP3ecFawIFYdvJB_cm-GvpCSbr8G8y_Mllj8f4x9nBH8pQux89_6gUY618iYv7tuPWBFfEbLx" +
  "tF2pZS6YC1aSfLQxeNe8djT9YjpvRZA";

const publicKey = `-----BEGIN PUBLIC KEY-----
  MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAnzyis1ZjfNB0bBgKFMSv
  vkTtwlvBsaJq7S5wA+kzeVOVpVWwkWdVha4s38XM/pa/yr47av7+z3VTmvDRyAHc
  aT92whREFpLv9cj5lTeJSibyr/Mrm/YtjCZVWgaOYIhwrXwKLqPr/11inWsAkfIy
  tvHWTxZYEcXLgAXFuUuaS3uF9gEiNQwzGTU1v0FqkqTBr4B8nW3HCN47XUu0t8Y0
  e+lf4s4OxQawWD79J9/5d3Ry0vbV3Am1FtGJiJvOwRsIfVChDpYStTcHTCMqtvWb
  V6L11BWkpzGXSW4Hv43qa+GSYOD2QU68Mb59oSk2OB+BtOLpJofmbGEGgvmwyCI9
  MwIDAQAB
  -----END PUBLIC KEY-----`;

const [header, payload, signature] = jwt.split(".");

const key = RSA.parseKey(publicKey);
const rsa = new RSA(key);

console.log(await rsa.verify(
  encode.base64url(signature),
  header + "." + payload,
  { algorithm: "rsassa-pkcs1-v1_5", hash: "sha256" },
));