PQ-single-address-backup - BIP-38 for P2MR (bc1z) - 104-char encrypted backup format

In addressing cryptographic security, the consideration of how a decoder acquires knowledge about the Key Derivation Function (KDF) and its parameters prior to decrypting an authenticated payload becomes crucial. A potential solution involves the use of a minimal outer header within the encryption schema. This header would include essential information such as the format version, the KDF identifier, and bounded KDF parameters. Importantly, this same header should also be utilized as AEAD associated data to aid the decoder in selecting the appropriate derivation procedure while simultaneously ensuring the integrity of the header against unauthorized modifications.

Furthermore, the differentiation between a wrong password and corrupted ciphertext presents a significant challenge in cryptographic systems utilizing Authenticated Encryption with Associated Data (AEAD). The implementation of a pre-Key Derivation Function (KDF) checksum can be instrumental in identifying ordinary transcription errors, enhancing the robustness of the system. However, it is recommended that the specification should cautiously label any discrepancies during decryption as “authentication failed.” This approach avoids explicitly stating a "wrong password," which might not always be the case, thereby providing a more secure and error-tolerant framework.