BUILDING

BUILD INSTRUCTIONS:
- Android SDK and NDK
- bash shell
- 7Zip command line tool '7z'
- wget
- awk

# ############################################################################
# Environment as typically set in ~/.bashrc
# ############################################################################

export JAVA_HOME=/cygdrive/c/d/jdk/
export PATH=${JAVA_HOME}/bin:${PATH}

# Android SDK location
SDK=/cygdrive/c/d/sdk

# Android NDK location/version; upgrade as needed/wanted
NDK=${SDK}/ndk/27.2.12479018

# Android minSdkVersion. The minimal version is 26, upgrade as needed/wanted
export ANDROID_MIN_SDK=26

# Only choose ONE of these, depending on your device...
# the first, "aarch64", is most likely the one you want.
export ANDROID_TARGET=aarch64-linux-android
# export ANDROID_TARGET=armv7a-linux-androideabi
# export ANDROID_TARGET=i686-linux-android
# export ANDROID_TARGET=x86_64-linux-android


export TOOLCHAIN=${NDK}/toolchains/llvm/prebuilt/windows-x86_64
export PATH=${SDK}/platform-tools:${TOOLCHAIN}/bin:${PATH}

# ############################################################################
# Define the versions for the external project code
#
# https://download.samba.org/pub/rsync/src/rsync-3.3.0.tar.gz
# https://mirror.ox.ac.uk/pub/OpenBSD/OpenSSH/portable/openssh-9.9p1.tar.gz
# https://matt.ucc.asn.au/dropbear/dropbear-2024.86.tar.bz2
# ############################################################################

export RSYNC_VERSION="rsync-3.3.0"
export OPENSSH_VERSION="openssh-9.9p1"
export DROPBEAR_VERSION="dropbear-2024.86"

# ############################################################################
# Setting up the toolchain
# ############################################################################

# The root directory of th Ssh4d project (i.e. where the projects .git is)
export PROJECT_ROOT=/cygdrive/c/Data/AndroidStudioProjects/Sshd4a/

# The working directory where the tarballs will be downloaded and git remotes will be setup.
# Defaults to current directory. Either make sure you are where you want to be,
# or modify the next line with an absolute path.

export SRC_ROOT=`pwd`

# Sanity checks for the .bashrc settings.
# TOOLCHAIN is expected to point to your ndk environment toolchain.
[ -n "${TOOLCHAIN}" ] || { echo "TOOLCHAIN must be set"; exit 1; }

if [ ! -d "$NDK" ]; then
  echo "$NDK does not exist."
  exit 1
fi

# info dump as reminder...
echo "ANDROID_TARGET=${ANDROID_TARGET}"
echo "ANDROID_MIN_SDK=${ANDROID_MIN_SDK}"

export AR=${TOOLCHAIN}/bin/llvm-ar
export CC=${TOOLCHAIN}/bin/${ANDROID_TARGET}${ANDROID_MIN_SDK}-clang
export AS=${CC}
export CXX=${TOOLCHAIN}/bin/${ANDROID_TARGET}${ANDROID_MIN_SDK}-clang++
export LD=${TOOLCHAIN}/bin/ld
export RANLIB=${TOOLCHAIN}/bin/llvm-ranlib
export STRIP=${TOOLCHAIN}/bin/llvm-strip

# content for ".gitattributes"
export GATRR="* text eol=lf\n*.txt text\n*.png binary\n"

# ############################################################################
# Step 2.1 - RSYNC - https://rsync.samba.org/
# ############################################################################

cd ${SRC_ROOT}
wget -q https://download.samba.org/pub/rsync/src/${RSYNC_VERSION}.tar.gz
7z x -so ${RSYNC_VERSION}* | tar xf -

# remove broken and/or unneeded rsync symlink
rm ${RSYNC_VERSION}/md2man

# rename the directory so we don't need to change the git remote names
export RSYNC="upstream-rsync"
mkdir -p ${RSYNC}/app/src/main/cpp/
mv ${RSYNC_VERSION} ${RSYNC}/app/src/main/cpp/rsync

# Prep rsync
cd ${RSYNC}
echo -e "${GATRR}" >.gitattributes
git init .
git add * .gitattributes
git commit -a -m "${RSYNC_VERSION}"
cd ${SRC_ROOT}

# Configure rsync
cd ${SRC_ROOT}/${RSYNC}/app/src/main/cpp/rsync
./configure --host ${ANDROID_TARGET} --disable-openssl --disable-xxhash --disable-zstd \
            --disable-lz4 \
            --disable-md2man --disable-roll-simd --disable-md5-asm --disable-roll-asm \
            --enable-largefile

cd ${PROJECT_ROOT}
# Add remote: "upstream-rsync" pointing to the location used above
git remote add upstream-rsync ${SRC_ROOT}/${RSYNC}
git fetch upstream-rsync
git merge --allow-unrelated-histories upstream-rsync/dev

#    All changes are (should be) marked with SSHD4A_*
#    Merge and solve conflicts as usual.

cd ${PROJECT_ROOT}/app/src/main/cpp/
./prebuild-rsyn.sh

#    Commit and build...

# ############################################################################
#  Step 2.2 - OPENSSH - https://github.com/openssh/openssh-portable
# ############################################################################

cd ${SRC_ROOT}
wget -q https://mirror.ox.ac.uk/pub/OpenBSD/OpenSSH/portable/${OPENSSH_VERSION}.tar.gz
7z x -so ${OPENSSH_VERSION}* | tar xf -

# rename the directory so we don't need to change the git remote names
export OPENSSH="upstream-openssh"
mkdir -p ${OPENSSH}/app/src/main/cpp/
mv ${OPENSSH_VERSION} ${OPENSSH}/app/src/main/cpp/openssh

# Prep openssh
cd ${OPENSSH}
echo -e "${GATRR}" >.gitattributes
git init .
git add * .gitattributes
git commit -a -m "${OPENSSH_VERSION}"
cd ${SRC_ROOT}

# Configure openssh
cd ${SRC_ROOT}/${OPENSSH}/app/src/main/cpp/openssh
# autoreconf is normally in /usr/bin
autoreconf
./configure --host ${ANDROID_TARGET} --disable-lastlog --disable-utmp --disable-wtmp \
            --enable-largefile --without-openssl


cd ${PROJECT_ROOT}
# Add remote: "upstream-openssh" pointing to the location used above
git remote add upstream-openssh ${SRC_ROOT}/${OPENSSH}
git fetch upstream-openssh

git merge --allow-unrelated-histories upstream-openssh/dev

#    Merge and solve conflicts as usual.
#    Typically just "Accept theirs" for all files
#    EXCEPT for our mandatory changes which are (should be) marked with SSHD4A_*
#
#    2024-11-29: files modified:
#      cpp/openssh/openbsd-compat/explicit_bzero.c
#
#    Commit and build...

# ############################################################################
# Step 2.3 - DROPBEAR - https://matt.ucc.asn.au/dropbear/dropbear.html
# ############################################################################

cd ${SRC_ROOT}
wget -q https://matt.ucc.asn.au/dropbear/${DROPBEAR_VERSION}.tar.bz2
7z x -so ${DROPBEAR_VERSION}* | tar xf -

# rename the directory so we don't need to change the git remote names
export DROPBEAR="upstream-dropbear"
mkdir -p ${DROPBEAR}/app/src/main/cpp/
mv ${DROPBEAR_VERSION} ${DROPBEAR}/app/src/main/cpp/dropbear

# Prep dropbear
cd ${DROPBEAR}
echo -e "${GATRR}" >.gitattributes
git init .
# ignore warnings about txt files in "rsa-testvectors"
git add * .gitattributes
git commit -a -m "${DROPBEAR_VERSION}"
cd ${SRC_ROOT}

# Configure dropbear
cd ${SRC_ROOT}/${DROPBEAR}/app/src/main/cpp/dropbear
./configure --host ${ANDROID_TARGET} --disable-syslog --disable-lastlog \
            --disable-utmp --disable-wtmp \
            --enable-bundled-libtom --enable-largefile


cd ${PROJECT_ROOT}
# Add remote: "upstream-dropbear" pointing to the location used above
git remote add upstream-dropbear ${SRC_ROOT}/${DROPBEAR}
git fetch upstream-dropbear

git merge --allow-unrelated-histories upstream-dropbear/dev

#    Merge and solve conflicts as usual.
#    Typically just "Accept theirs" for all files
#    EXCEPT for our mandatory changes which are (should be) marked with SSHD4A_*
#
#    2024-11-29: files modified:
#      cpp/dropbear/src/
#         common-session.c
#         dbrandom.c
#         dbutil.c
#         localoptions.h
#         scp.c
#         signkey.c
#         svr-auth.c
#         svr-authpasswd.c
#         svr-authpubkey.c
#         svr-chansession.c
#         svr-main.c
#
#    Merge and solve conflicts as usual.

cd ${PROJECT_ROOT}/app/src/main/cpp
./prebuild-dropbear.sh

#    Commit and build...