These tools are intended to make it easier to verify that the binaries resulting from openEuler builds are reproducible.
For this, we rebuild twice locally from source with variations in
- datetime
- hostname
within opensource libfaketime in Open Build Service(OBS), unpack the differenc packages and compare the results using the build-compare script (diffoscope) that abstracts away some unavoidable (or unimportant) differences.
Steps:
- Install libfaketime：
get libfaketime source https://github.com/opensourceways/reproducible-builds-libfaketime
make
make install
- To mock datetime and hostname, set the libfaketime environment
echo 'export LD_PRELOAD=/usr/local/lib/faketime/libfaketimeMT.so.1' >> /etc/profile
echo 'export FAKETIME="2022-05-01 11:12:13"' >> /etc/profile
echo 'export FAKEHOSTNAME=fakename' >> /etc/profile
- Solve the binary differences caused by time & random numbers in Python during the compilation of source packages
echo 'export SOURCE_DATE_EPOCH=1' >> /etc/profile
echo 'export PYTHONHASHSEED=0' >> /etc/profile
- We added a blacklist and whitelist mechanism to libfaketime, In blacklist mode, libfaketime only hooks commands in the blacklist; In white list mode, libfaketime will skip the commands in the white list and hook all other commands. Users can use the blacklist or whitelist function by downloading the corresponding branch. For example:
# blacklist mode
export BLACKLIST=ls,make
# whitelist mode
export WHITELIST=ls,make
- In OBS, the hostname used in the build will be entered into the rpm package and the two builds will be inconsistent. Therefore, we also integrate the function of hooking hostname in libfaketime.This function is currently integrated in the whitelist branch.
export FAKENAME=fakename
- OBS rebuild packages twice locally from software source
- Unpack your two packages using the unpacker.py tool
python unpacker.py ${first package path} ${second package path}
- Display differences using diffoscope :
yum install diffoscope
diffoscope ${first file path} ${second file path} --html diff.html