@li0ard/tsemrtd/dist/dg7.js

simple library for eMRTD. supports browsers, node, bun and more!

import { TLV } from "@li0ard/tinytlv";
import { Enums } from "./index";
/**
 * Class for working with DG7 (Signature)
*/
export class DG7 {
    readImage(tlv) {
        if (parseInt(tlv.tag, 16) != 0x5f43)
            throw new Error(`Invalid object tag "0x${tlv.tag}", expected 0x5f43`);
        return tlv.byteValue;
    }
    /**
     * Get image of signature
     * @param data Data of EF.DG7 file
     */
    static load(data) {
        let tlv = TLV.parse(data);
        if (parseInt(tlv.tag, 16) != Enums.TAGS.DG7)
            throw new Error(`Invalid DG7 tag "0x${tlv.tag}", expected 0x${Enums.TAGS.DG7.toString(16)}`);
        let bict = tlv.childs[0];
        if (parseInt(bict.tag, 16) != 0x02)
            throw new Error(`Invalid object tag "0x${bict.tag}", expected 0x02`);
        let bitCount = parseInt(bict.value, 16);
        let results = [];
        for (let i = 0; i < bitCount; i++) {
            results.push(new DG7().readImage(tlv.childs[i + 1]));
        }
        return results;
    }
}