fetch
Run the exchange and return the raw, verified info-dict bytes (whose SHA-1, or SHA-256 for a v2 hash, equals infoHash), or null if the peer can't/won't provide them within timeoutMillis.
Run the exchange and return the raw, verified info-dict bytes (whose SHA-1, or SHA-256 for a v2 hash, equals infoHash), or null if the peer can't/won't provide them within timeoutMillis.