35 lines
1.0 KiB
Plaintext
35 lines
1.0 KiB
Plaintext
import { decode as base64url } from './base64url.js';
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import { decoder } from '../lib/buffer_utils.js';
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import isObject from '../lib/is_object.js';
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export function decodeProtectedHeader(token) {
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let protectedB64u;
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if (typeof token === 'string') {
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const parts = token.split('.');
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if (parts.length === 3 || parts.length === 5) {
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;
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[protectedB64u] = parts;
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}
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}
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else if (typeof token === 'object' && token) {
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if ('protected' in token) {
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protectedB64u = token.protected;
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}
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else {
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throw new TypeError('Token does not contain a Protected Header');
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}
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}
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try {
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if (typeof protectedB64u !== 'string' || !protectedB64u) {
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throw new Error();
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}
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const result = JSON.parse(decoder.decode(base64url(protectedB64u)));
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if (!isObject(result)) {
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throw new Error();
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}
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return result;
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}
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catch {
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throw new TypeError('Invalid Token or Protected Header formatting');
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}
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}
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