webnative/lib/did/util.js

import { arrbufs } from "../common/index.js";
import { KeyType } from "./types.js";
export const EDWARDS_DID_PREFIX = new Uint8Array([0xed, 0x01]);
export const BLS_DID_PREFIX = new Uint8Array([0xea, 0x01]);
export const RSA_DID_PREFIX = new Uint8Array([0x00, 0xf5, 0x02]);
export const BASE58_DID_PREFIX = 'did:key:z';
/**
 * Magic bytes.
 */
export function magicBytes(keyType) {
    switch (keyType) {
        case KeyType.Edwards: return EDWARDS_DID_PREFIX;
        case KeyType.RSA: return RSA_DID_PREFIX;
        case KeyType.BLS: return BLS_DID_PREFIX;
        default: return null;
    }
}
/**
 * Parse magic bytes on prefixed key-buffer
 * to determine cryptosystem & the unprefixed key-buffer.
 */
export const parseMagicBytes = (prefixedKey) => {
    // RSA
    if (hasPrefix(prefixedKey, RSA_DID_PREFIX)) {
        return {
            keyBuffer: prefixedKey.slice(RSA_DID_PREFIX.byteLength),
            type: KeyType.RSA
        };
        // EDWARDS
    }
    else if (hasPrefix(prefixedKey, EDWARDS_DID_PREFIX)) {
        return {
            keyBuffer: prefixedKey.slice(EDWARDS_DID_PREFIX.byteLength),
            type: KeyType.Edwards
        };
        // BLS
    }
    else if (hasPrefix(prefixedKey, BLS_DID_PREFIX)) {
        return {
            keyBuffer: prefixedKey.slice(BLS_DID_PREFIX.byteLength),
            type: KeyType.BLS
        };
    }
    throw new Error("Unsupported key algorithm. Try using RSA.");
};
/**
 * Determines if an ArrayBuffer has a given indeterminate length-prefix.
 */
export const hasPrefix = (prefixedKey, prefix) => {
    return arrbufs.equal(prefix, prefixedKey.slice(0, prefix.byteLength));
};
export const toKeyType = (str) => {
    switch (str) {
        case 'rsa': return KeyType.RSA;
        case 'ed25519': return KeyType.Edwards;
        case 'bls12-381': return KeyType.BLS;
    }
    throw new Error(`Key Type ${str} not supported`);
};
//# sourceMappingURL=util.js.map