Implement Cipheriv.setAutoPadding

[littledivy]

#18455 (comment)

@mllnd stumbled upon missing method when using npm:ethereum-cryptography.
https://github.com/ethereum/js-ethereum-cryptography/blob/cbb283febc4641bf1c5c365a2a16037032f2d23e/src/aes.ts#L69-L71

Error: Not implemented: crypto.Cipheriv.prototype.setAutoPadding
    at notImplemented (ext:deno_node/_utils.ts:9:11)
    at Cipheriv.setAutoPadding (ext:deno_node/internal/crypto/cipher.ts:46:9)

[barthuijgen]

This method is definitely not just used by crypto(currency) libraries. I've had a project that I needed to implement a specific decryption logic to work with a 3rd party and this method was needed, so I was forced to switch to nodejs.

I couldn't find any other way to implement this in Deno either, the web subtle crypto api that Deno uses has no support for this.

Please prioritize the issue! 🙏

[littledivy]

Rough outline on how to implement this:

• Add a autoPadding: boolean = true default field to the class Cipher in ext/node/polyfills/internal/crypto/cipher.ts.
• During final(), pass this flag to Rust.

• deno/ext/node/ops/crypto/cipher.rs

  Line 212 in 3f4639c

  fn r#final(self, input: &[u8], output: &mut [u8]) -> Result<Tag, AnyError> {

  
  When auto padding is disabled, divide final data into blocks of cipher's block size and call encrypt_blocks_b2b_mut.

Similar logic can be applied for Decipher