fix: aes was not copied correctly in raw copy methods

[im7mortal]

Summary

Fixes loss of AES encryption metadata when copying entries without a password and ensures AES headers/flags are spec-compliant.

• Raw copies keep encrypted flag and AES 0x9901 extra field (no re-encryption).
• ZipFile::options() now carries AES metadata so downstream writes produce correct headers.

Key Changes

• write.rs:

  • start_entry: write AES extra field (0x9901) using aes_mode, set method=99.
  • raw_copy_file_rename_internal: no password required; relies on options() metadata.

• types.rs: encrypted flag set when aes_mode present.

• read.rs: options() preserves AES metadata for copied entries.

Impact

• No public API changes.
• Non-AES entries unchanged.
• All tests pass (including AES cases).

[gemini-code-assist]

Summary of Changes

Hello @im7mortal, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses an issue where AES encryption metadata was not correctly handled during raw file copying operations within zip archives. The changes ensure that when an AES-encrypted entry is copied without re-encryption, its encryption flags and associated metadata are accurately preserved, maintaining spec compliance and data integrity. This improves the reliability of copying encrypted files within the library.

Highlights

• AES Metadata Preservation: Ensure AES encryption metadata is correctly preserved during raw file copying operations, preventing data loss or corruption.
• ZipFile Options Update: ZipFile::options() now includes AES metadata, ensuring proper header generation for subsequent writes.
• Encrypted Flag Correction: The 'encrypted' flag in ZipFileData is now correctly set based on the presence of AES mode.
• FileOptions Extension: FileOptions struct has been extended to carry AES mode information.
• ZipWriter Enhancement: The start_entry function in ZipWriter now correctly writes the AES extra field (0x9901) and sets the compression method to 99 for raw copies of AES entries.
• New Test Case: A new test case raw_copy_from_aes_zip has been added to validate the integrity of raw-copied AES files.

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[gemini-code-assist]

Code Review

This pull request correctly addresses an issue where AES encryption metadata was lost during raw copy operations. The changes ensure that AES metadata is preserved in FileOptions and used by the writer to generate spec-compliant headers for copied entries. The logic is sound, and the addition of a new test case, raw_copy_from_aes_zip, is excellent as it thoroughly validates the fix. I have one suggestion to improve the readability of the logic for setting the encrypted flag.

[Pr0methean]

Thanks! This will be merged if all tests pass.

[im7mortal]

@Pr0methean the test cases without aes-crypto were failing because I applied suggestion from gemini-code-assist.

I reverted it to the original version. Please restart tests