Skip to content

Instantly share code, notes, and snippets.

@chunlea
Forked from geoff-nixon/ruby_revealer.sh
Created January 6, 2017 20:16
Show Gist options
  • Save chunlea/db26c683ed59f026dd9053b6b7064bca to your computer and use it in GitHub Desktop.
Save chunlea/db26c683ed59f026dd9053b6b7064bca to your computer and use it in GitHub Desktop.
#!/usr/bin/sudo sh
## ruby_revealer.sh -- decrypt obfuscated GHE .rb files. 2.0.0 to 2.3.1+.
## From `strings ruby_concealer.so`:
##
## > This obfuscation is intended to discourage GitHub Enterprise customers
## > from making modifications to the VM.
##
## Well, good, as long as its not intended to discourage *me* from doing this!
## After all, I'm not a GitHub Enterprise customer. I'm just some dude who
## grabbed the .ova file off the internet!
##
## > We know this 'encryption' is easily broken.
##
## Err, yeah. Just do a binary `s/eval/puts/`. Like this!
# So...
# A version of the ruby_concealer.so with just such a patch, xz'd and base64'd.
ruby_revealer_so='
/Td6WFoAAATm1rRGAgAhARwAAAAQz1jM4BfnCD1dAD+RRYRoPYmm2orhgzJO2QUBECVj1ssSLXULCO
u4VR2ikjxchQNbmHH657uWGUHjncEu3kPs6K/1/Co5mEyIhDIbS/bptFYX+6ysuGr2qe3Bk3rv3NIx
WhlvCMhgbNv7OXOnrcMZJB0nwb6AXTA4IG8Z6UwtDVtZkTzkJ/YbOh99Mb/HDhynIgRz0WjbZOQZH6
ROPqGF4BK8iO58okHz/aQBKgdFnoyLCWvsY5P+x4agRvYbapHKdkG3dpcZVDSecYOXTgVPaH+ln47d
F0uOhn22XPq01ueLSky1VwJAPV1YftJ9xC4V9DYrLwuC9wcv4DhfhoEakR0uzySCRDGdWW8x+6ptql
qXoE5nQqdpOubKLqiZaTjE3XejV9sf5habmvS8D10vUI5Z4Tu7mQUvKoE3/FmnZVI2zVbHSGONA8g0
k9LUKorBATSye8Gor3DzbsCBEVM2jRHWBvGBnlbjhuFus81EA1egk2sYCh+re6GHiSGsPIMLqnAwjS
cpLAqQi9M+2Tg+hYCusmzTlt+wSbUajNkYMe6W5gNYEEUcTx7SjEPDGXDKsGSNrOJYeNAHAnpc1Vid
x+iIldYCuZOWjJp/UFMW6QUyJZil88xR9TGstXd3EIPNY3XDQFRaIToymS1tLu/zcNQZbx70ndnesJ
ugORINdK68kfPiP/6/xjIzXT5PPzQSm8TGKa8bajCJ7drRI+KgH8bfcRFdBWRPh3x2yxdlkIk+lwpH
+JtvI4qWPa44GlVrmx7vsBxTT4T0Oy1EWePExu108Wjj4E1BjWR1q2Wb0Vi0bEyZ8T3Kzx6e3QDw2O
Hc14HiG5YdO9IoGS+UgWwp1Z+6GJuXUTHBONS/lTiC3wjXdK08UPRl8fXhbeHt6tagKQhp3FjP/Iyl
6j8N6f0o3/aJ5medT5BBdAp7eJkLSASWQIAgTzfd+25y/LnvtWEMPH1G1KUeUDA91VZvl7oLTawpm7
GWBDKKVqn+UidfG53ZcLXcEUegVWRQAwFcBon8KNi8uDsoFWD38nWW2VvXoHoglf1krXi3sawB5AxK
IrAudhrn9c8cz4dWtMYqIRZj+IGeTr+QmA+8ygIsrSDd03CNMfOQBrK00EV5TpivScHRyLiW+24gVv
xocvTlT+9F8XoLWwitCKRkf76+6znd/6kFDJgQ3gIcPEaxlfRFTw6VIfYnv3fY1VhvASnhLwe6hLNt
nT+wkgHfAKZR7MJ+SWV5rjorO2NLrQBZWhL1LO/XSt7LnlwurkpyNjk1xpVb9EeCbbqTMhfMW/VQKx
uqJNZhAb2KU7y1YFubKl024DyWuOtghGQ5ZZKtmfDwpib7KYN6VrlwGsGRP/N3bDqvcs72ylXhbGR8
HnyGTlwQL11pqWWnhJBJET2VkpYwNAOJ+m0+BX/Ej0bcDSGMQhbhQ75b8BHVsd/5Hbx/B7mb0cq7O4
50QECkanmBVRZ8ZROFgIGJHiYp6kC+zOOcQ8Roy5tCrThmB5fN9Fti5wZspVoUOYddyKbCyX4DBrNJ
u3IL+mwXHrC8hk7s71QrxJ+AtrhBhxaGLHe6xb+jy5uvoUH8Ywicq0GNKeFoo1kgELu2/JJr0omBI4
UKTWgG6qlRiXVspnZd3xpuWky0BKRVHf1KEXy+LFUYEkVe6prP8QT1mT/xCQuPod72INU7b0VEAQ6n
X6iavj+5dbg2ZbWDO/yiqnVKkogodr5E5iUtinu+X0eKPJJflvTUZGBqKNxiZO9i3wvCpoZ5GoI89J
JTGscsxEb7PQWhdTxCyw9nO0xyvT9M3a9iqbmd9TDXMHosynWz+jAizpRqwMA+vBnOitbsxeKJzN5n
cPIIDwyumHBDyryFr41MHnIufRXzDw8VX0rddXLSPKbwyVq2ogA8mLP1j88FqO3EkfhCE/Jaxb/kJr
BRp4RNyTi5bVwfz3teLsGCB2RspIFd2NQlzIVUPqTzmHNdQcsC6PeBA8cf/TkyS+6ppndLIYs2uT8N
24e/r9APRskRS1BLO1bI1c9kvozyNZ8MVj9oZ/mDCVXdxBqxXQSyHib5HIQaBHerD1QxziBU68KXet
BePKvjlhG+el4dV2DC0g0eJN/7NHHzTJnTLIj1DUxER76LJprZnI8VHpxT2ac/JkqddBMn9yrwWfw6
ay0e+6AgKnFXpjkLvt3x5Y96yTcnxZQy9zzK5Y7+rWTEBXCc+vwcfDGo3TcclIMpDEc9ddRin4E2JK
990Lxacz6FxvQh0VqEHPG8VNBd3QopN/v50cgs9AJtLatKhfZHLLVXvFA1N4yyBysl0eBqKhSHS+mQ
g8efRUqQs3nAV4A3XiFGOI4rP7eTjrkcwcQ+HbGmLoYmRCH2mjBTexkldCw/wvkB7d9sRHbYgcJ5mL
TUYD2p1H6v6UO46HRwsvK8+v90q6lMzPEp5ejfFWBK0YAC7xEBk+egqWndZ9XpZ9P3EMkPwvgJK6+R
VPv5CaiO3V3jEjzTsnqFo+oRj1/rvG+JUkyA1DVVsftQNiXL/0I1pBbx6nnW2fG8IIdZj4cXQchV1R
NTFR1hbhZobbAf4anPp5ewTYlcQQcsnswfeMywClTMdThS3X0BxUbuPwjl9h6hnmN2LWk0cH/Rr6Gc
l5jpZr1dFGXYpVyaA7zFfVry/2hSPHUpZJeb+amqAZqd6RUocj5d1oKwfJ5D7tjJMkgfQ4aiV5XGQL
EhPXzVaJXkk2PwQhRgUyh+cAvQWjOt+smlpAHTLnW7b8r0/1V1aJPmN9OMI5tshQD9UvkWCbpIg0cu
Y6QK6t29oIcTo20qU0+gqg8auYrzJyoC3JGgj+gIo2B9AAAAAABA7jDAP3LMnQAB2RDoLwAAsmZetr
HEZ/sCAAAAAARZWg=='
# Find the existing .so (don't hardcode it).
ruby_concealer_so=$(find / -name ruby_concealer.so)
# Find the corresponding ruby and put it in our PATH.
export PATH=$(echo $ruby_concealer_so | sed s'|lib.*|bin|'):$PATH
# Backup the original file.
mv $ruby_concealer_so $ruby_concealer_so.bak
# Overwrite the original.
echo "$ruby_revealer_so" | base64 --decode | xz -dc > $ruby_concealer_so
touch -r $ruby_concealer_so.bak $ruby_concealer_so
# This function takes the name of the file to be decrypted from stdin.
# There's some weirdness with a couple (pre|post)-receive-hooks in earlier GHE
# versions; these seem to like it a little better if one `cd`s to the directory
# first, using bundler if necessary.
# They still squawk a bit but seem to decrypt fine. We're avoiding a
# temporary file by setting a variable containing the decrypted contents;
# /bin/echo is necessary to avoid interpolating escaped newlines, etc.
ruby_revealer(){
f=$(cat); cd $(dirname $f)
# Save the original.
cp -p $f $f.bak
# Output our replacement.
r=$(ruby $(basename $f) 2>/dev/null ||
bundle exec 'ruby $(basename $f) 2>/dev/null' 2>/dev/null)
r=$(/bin/echo "$r" | head -n -2)
# If it has failed, move the original back.
# (A few do, due to bugs *in the code* itself, I believe.)
[ $(/bin/echo "$r" | wc -c) -lt 2 ] && (rm -f $f && mv $f.bak $f) ||
(/bin/echo "$r" > $f && touch -r $f.bak $f && rm -f $f.bak)
}
# Presto change-o.
voila(){
echo "One moment..." >&2 # While we grep through a bunch of other files...
for c in $(grep --include \*.rb -Rl __ruby_concealer__ /data 2>/dev/null); do
echo Revealing $c ... >&2; echo $c | ruby_revealer
done
}
# Put the module back how we found it; be sure to use a redirect to
# preserve permissions and modification dates, etc.
cleanup(){
cp -p $ruby_concealer_so.bak $ruby_concealer_so &&
rm -f $ruby_concealer_so.bak
}
# Make absolutely sure we put the .so back properly so we're not foobar'd.
trap cleanup INT
voila
cleanup
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment