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Android

Radare2 can be cross-compiled for other architectures/systems as well, like Android.

Prerequisites

- Python 3

- Meson

- Ninja

- Git

- Android NDK

Step-by-step

Download and extract the Android NDK

Download the Android NDK from the official site[1] and extract it somewhere on your system (e.g. `/tmp/android-ndk`)

1: official site

Make

Specify NDK base path

$ echo NDK=/tmp/android-ndk  > ~/.r2androidrc

Compile + create tar.gz + push it to connected android device

./sys/android-build.sh arm64-static

You can build for different architectures by changing the argument to `./sys/android-build.sh`. Run the script without any argument to see the accepted values.

Meson

Create a cross-file for meson

Meson needs a configuration file that describes the cross compilation environment (e.g. `meson-android.ini`).

You can adjust it as necessary, but something like the following should be a good starting point: ``` [binaries] c = '/tmp/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android28-clang' cpp = '/tmp/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android28-clang++' ar = '/tmp/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android-ar' as = '/tmp/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android-as' ranlib = '/tmp/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android-ranlib' ld = '/tmp/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android-ld' strip = '/tmp/android-ndk/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android-strip' pkgconfig = 'false'

[properties] sys_root = '/tmp/android-ndk/sysroot'

[host_machine] system = 'android' cpu_family = 'arm' cpu = 'aarch64' endian = 'little' ```

Compile with meson + ninja

Now setup the build directory with meson as usual: ``` $ CFLAGS="-static" LDFLAGS="-static" meson --default-library static --prefix=/tmp/android-dir -Dblob=true build --cross-file ./meson-android.ini ```

A bit of explanation about all the options: * `CFLAGS="-static"`, `LDFLAGS="-static"`, `--default-library static`: this ensure that libraries and binaries are statically compiled, so you do not need to properly set LD_* environment variables in your Android environment to make it find the right libraries. Binaries have everything they need inside.

- `-Dblob=true`: it tells meson to compile just one binary with all the needed

code for running `radare2`, `rabin2`, `rasm2`, etc. and creates symbolic links to those names. This avoids creating many statically compiled large binaries and just create one that provides all features. You will still have `rabin2`, `rasm2`, `rax2`, etc. but they are just symlinks to `radare2`.

- `--cross-file ./meson-android.ini`: it describes how to compile radare2 for Android

Then compile and install the project: ``` $ ninja -C build $ ninja -C build install ```

Move files to your android device and enjoy

At this point you can copy the generated files in /tmp/android-dir to your Android device and running radare2 from it.

For example: ``` $ cd /tmp && tar -cvf radare2-android.tar.gz android-dir $ adb push radare2-android.tar.gz /data/local/tmp $ adb shell DEVICE:/ $ cd /data/local/tmp DEVICE:/data/local/tmp $ tar xvf radare2-android.tar.gz DEVICE:/data/local/tmp $ ./android-dir/bin/radare2 Usage: r2 [-ACdfLMnNqStuvwzX] [-P patch] [-p prj] [-a arch] [-b bits] [-i file] [-s addr] [-B baddr] [-m maddr] [-c cmd] [-e k=v] file|pid|-|--|= ```