Quick how-to cross compile tinc for Android (done from $HOME/android/):

- Download Android NDK and setup local ARM toolchain:

        wget http://dl.google.com/android/ndk/android-ndk-r8b-linux-x86.tar.bz2
        tar xfj android-ndk-r8b-linux-x86.tar.bz2
        ./android-ndk-r8b/build/tools/make-standalone-toolchain.sh --platform=android-5 --install-dir=/tmp/my-android-toolchain

- Download and cross-compile OpenSSL for ARM:

        wget http://www.openssl.org/source/openssl-1.0.1c.tar.gz
        tar xfz openssl-1.0.1c.tar.gz
        cd openssl-1.0.1c
        ./Configure dist
        make CC=/tmp/my-android-toolchain/bin/arm-linux-androideabi-gcc AR="/tmp/my-android-toolchain/bin/arm-linux-androideabi-ar r" RANLIB=/tmp/my-android-toolchain/bin/arm-linux-androideabi-ranlib

- Clone and cross-compile tinc:

        git clone git://tinc-vpn.org/tinc
        cd tinc
        autoreconf -fsi
        CC=/tmp/my-android-toolchain/bin/arm-linux-androideabi-gcc ./configure --host=arm-linux --disable-lzo --with-openssl-lib=$HOME/android/openssl-1.0.1c --with-openssl-include=$HOME/android/openssl-1.0.1c/include/
        make -j5
