Create DANE TLSA Records for Certificate Pinning Generate DANE TLSA DNS records for certificate authentication.

The tool works by using the `crypto.subtle.digest` browser API to calculate the SHA-256 digest of the provided certificate data when necessary. It first removes any whitespace and PEM header/footer from the input data, then converts it to a Uint8Array using the `atob` function and `charCodeAt` method. If the matching type is set to 1 (SHA-256) and the cert data length exceeds 64 characters, it attempts to calculate the SHA-256 digest of the certificate bytes. The resulting hash is then formatted into the TLSA record string along with other input parameters such as hostname, port number, usage, selector, and matching type.

The React `useState` hook is used to manage the state of various input fields including hostname, port, usage, selector, matching, cert data, output, and copied status. When the generate button is clicked, it triggers the `generate` function which updates the output state with the generated TLSA record string in the format "_<port>._tcp.<hostname> IN TLSA <usage> <selector> <matching> <hash>". The tool also utilizes the `copyToClipboard` utility function to copy the generated record directly to the clipboard when the copy button is clicked. This functionality relies on the browser's ability to support asynchronous clipboard operations.

The input parameters are validated and sanitized before being used in the TLSA record generation process, ensuring that only valid data is processed. For example, the port number is parsed as an integer using `parseInt` with a default value of 443 if the input cannot be parsed. The React `useCallback` hook is used to memoize the `generate` and `copy` functions so they are not recreated unnecessarily on every render cycle, improving performance by reducing unnecessary computations.