mirror of
https://github.com/trezor/trezor-firmware.git
synced 2024-11-26 09:28:13 +00:00
129 lines
4.6 KiB
Markdown
129 lines
4.6 KiB
Markdown
# Reproducible build
|
|
|
|
We want to invite the wider community to participate in the verification of the firmware
|
|
built by Trezor Company. With reasonable effort you should be able to build the firmware
|
|
and verify that it's identical to the official firmware.
|
|
|
|
Trezor Firmware uses [Nix](https://nixos.org/), [Poetry](https://python-poetry.org/) and
|
|
[Cargo](https://doc.rust-lang.org/cargo/) to make the build environment deterministic.
|
|
We also provide a Docker-based script so that the build can be performed with a single
|
|
command on usual x86 Linux system.
|
|
|
|
## Building
|
|
|
|
First you need to determine which *version tag* you want to build:
|
|
* for Trezor One it is `legacy/vX.Y.Z`, e.g. `legacy/v1.10.3`,
|
|
* for newer models, it is `core/vX.Y.Z`, e.g. `core/v2.4.2`.
|
|
|
|
Assuming you want to build `core/v2.8.3`:
|
|
|
|
1. install [Docker](https://www.docker.com/)
|
|
2. clone the firmware repository: `git clone https://github.com/trezor/trezor-firmware.git`
|
|
3. go into the firmware directory: `cd trezor-firmware`
|
|
4. checkout the version tag: `git checkout core/v2.8.3`
|
|
5. run: `bash build-docker.sh core/v2.8.3`
|
|
|
|
After the build finishes the firmware images are located in:
|
|
* `build/legacy/firmware/firmware.bin` and `build/legacy-bitcoinonly/firmware/firmware.bin` for Trezor One,
|
|
* `build/core-<model>/firmware/firmware.bin` and `build/core-<model>-bitcoinonly/firmware/firmware.bin` for later models.
|
|
|
|
### Model identifiers
|
|
|
|
You can speed up the build process by adding options to the script:
|
|
|
|
* `--skip-core` if you are only building for Trezor One,
|
|
* `--skip-legacy --models=A,B,C` to only build for specific model(s) which are not Trezor One.
|
|
|
|
The following models are supported:
|
|
|
|
* **`T`** - Trezor Model T
|
|
* **`R`** - Trezor Safe 3 rev.A
|
|
* **`T3B1`** - Trezor Safe 3 rev.B
|
|
* **`T3T1`** - Trezor Safe 5
|
|
|
|
Examples:
|
|
|
|
```sh
|
|
bash build-docker.sh --skip-core legacy/v1.10.3 # build only for Trezor One
|
|
bash build-docker.sh --skip-legacy --models=T3T1 core/v2.8.3 # build only for Trezor Safe 5
|
|
```
|
|
|
|
## Verifying
|
|
|
|
The result won't be bit-by-bit identical with the official images because the
|
|
official images are signed while local builds aren't.
|
|
|
|
### Trezor T and the Safe family
|
|
|
|
You can use `trezorctl` to download the official firmware image for your device:
|
|
|
|
```sh
|
|
trezorctl firmware download --model t3t1 --version 2.8.3
|
|
```
|
|
|
|
Or locate the firmware image in the [Trezor Data repository](https://github.com/trezor/data/tree/master/firmware).
|
|
|
|
The firmware binary starts with a [vendor header](../hardware/model-t/boot.md#vendor-header)
|
|
whose size is:
|
|
|
|
* Model T: 4608 bytes
|
|
* Safe 3: 512 bytes
|
|
* Safe 5: 1024 bytes
|
|
|
|
The vendor header is followed by a [firmware header](../hardware/model-t/boot.md#firmware-header)
|
|
that contains a 65-byte signature at offset `0x3bf` (959 in decimal).
|
|
|
|
You will need to calculate the right offset for the signature based on the model:
|
|
|
|
* Model T: 4608 + 959 = 5567
|
|
* Safe 3: 512 + 959 = 1471
|
|
* Safe 5: 1024 + 959 = 1983
|
|
|
|
Zero out the signature data to obtain an image identical to the one built locally:
|
|
|
|
```sh
|
|
OFFSET=<your offset here>
|
|
# the following line removes 65 bytes of signature data from the official firmware
|
|
dd if=/dev/zero of=trezor-t3t1-2.8.3.bin bs=1 seek=$OFFSET count=65 conv=notrunc
|
|
|
|
# the following two lines print out the hashes of the firmwares
|
|
sha256sum trezor-t3t1-2.8.3.bin
|
|
sha256sum build/core-T3T1/firmware/firmware.bin
|
|
```
|
|
|
|
### Trezor One
|
|
|
|
You can use `trezorctl` to download the official firmware image for your device:
|
|
|
|
```sh
|
|
trezorctl firmware download --model 1 --version 1.10.3
|
|
```
|
|
|
|
Or locate the firmware image in the [Trezor Data repository](https://github.com/trezor/data/tree/master/firmware).
|
|
|
|
Official Trezor One firmware older than 1.12 starts with [256-byte legacy
|
|
header](../hardware/model-one/firmware-format.md) used for compatibility with old
|
|
bootloaders. Locally built firmware doesn't have this header.
|
|
|
|
```
|
|
# strip legacy header
|
|
tail -c +257 trezor-1.10.3.bin > trezor-1.10.3-nolegacyhdr.bin
|
|
```
|
|
|
|
The [v2 header](../hardware/model-one/firmware-format.md#v2-header) has 3x65
|
|
bytes of signature data at offset 0x220. Overwrite by zeros to obtain image
|
|
identical to the one built locally.
|
|
|
|
```
|
|
dd if=/dev/zero of=trezor-1.10.3-nolegacyhdr.bin bs=1 seek=544 count=195 conv=notrunc
|
|
|
|
sha256sum trezor-1.10.3-nolegacyhdr.bin
|
|
sha256sum build/legacy/firmware/firmware.bin
|
|
```
|
|
|
|
_Note: Fingerprints displayed for T1 at the end of `build-docker.sh` do not match fingerprints of
|
|
official firmware due to the legacy header._
|
|
|
|
_Note: T1 firmware built this way won't boot because unsigned firmware needs to be built with
|
|
[`PRODUCTION=0`](../legacy/index.md#combining-bootloader-and-firmware-with-various-production-settings-signedunsigned)._
|