image4-util

Pure Rust tool for handling Image4 files (aka IMG4, IM4P, IM4M, IM4R).

Features

• Extract payload contents from either Image4 containers (IMG4) or Image4 payload files (IM4P).
• Create either full Image4 containers or Image4 payload files.
• Decrypt encrypted images using known AES key and IV.
• Decompress images compressed using LZSS and LZFSE (LZVN is not supported yet).
• Parse, create and sign Image4 manifests. Both signed and unsigned manifests are supported.
• Create certificates for signing Image4 manifests.

Installation

cargo install image4-util

Logging

The logging implementation is based on the env_logger crate. There are 3 log levels: info, warn and error (non-release builds support the debug log level). By default, only warning and error levels are enabled. You can set a different minimum log level using the IMAGE4_LOG environment variable (set to off to turn off the logging completely).

Example:

By default image4-util isn't verbose:

$ image4-util extract --iv xxx --key xxx -v llb.im4p
[?] File at llb.bin exists. Do you want to replace it? yes
$

It's quite verbose, however, if you enable the info log level.

$ IMAGE4_LOG=info image4-util extract --iv xxx --key xxx llb.im4p
[*] Extracting file at 'llb.im4p' to 'llb.bin'.
[*] 4CC tag: illb
[*] Builder string: iBoot-7429.41.5
[?] File at llb.bin exists. Do you want to replace it? yes
[*] Decompressed 606278 bytes into 1319704 bytes.
[*] Success.
$

Here instead of xxx will be your actual key and IV.

Minimum Supported Rust Version

This crate requires at least Rust 1.65. An MSRV change will be accompanied by a minor version bump

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.