padding.js 819 B

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  1. export function pkcs7Pad(data) {
  2. const padder = 16 - (data.length % 16);
  3. const result = new Uint8Array(data.length + padder);
  4. result.set(data);
  5. for (let i = data.length; i < result.length; i++) {
  6. result[i] = padder;
  7. }
  8. return result;
  9. }
  10. export function pkcs7Strip(data) {
  11. if (data.length < 16) {
  12. throw new TypeError('PKCS#7 invalid length');
  13. }
  14. const padder = data[data.length - 1];
  15. if (padder > 16) {
  16. throw new TypeError('PKCS#7 padding byte out of range');
  17. }
  18. const length = data.length - padder;
  19. for (let i = 0; i < padder; i++) {
  20. if (data[length + i] !== padder) {
  21. throw new TypeError('PKCS#7 invalid padding byte');
  22. }
  23. }
  24. return new Uint8Array(data.subarray(0, length));
  25. }
  26. //# sourceMappingURL=padding.js.map