#!/bin/bash -eu
# Copyright 2018 Google Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
################################################################################

# Case-sensitive names of internal Firefox fuzzing targets. Edit to add more.
FUZZ_TARGETS=(
  SdpParser
  StunParser
  ContentParentIPC
  ContentSecurityPolicyParser
  # Qcms # needn't be enabled; has its own project with more sanitizers/engines
)

# Firefox object (build) directory.
OBJDIR=$WORK/obj-fuzz

[[ $SANITIZER = "coverage" ]] && touch $OUT/empty && exit 0

# Firefox fuzzing build configuration.
cat << EOF > mozconfig
ac_add_options --disable-debug
ac_add_options --disable-elf-hack
ac_add_options --disable-jemalloc
ac_add_options --disable-crashreporter
ac_add_options --enable-fuzzing
ac_add_options --enable-optimize=-O1
ac_add_options --enable-debug-symbols=-gline-tables-only
ac_add_options --enable-address-sanitizer
mk_add_options MOZ_OBJDIR=${OBJDIR}
mk_add_options MOZ_MAKE_FLAGS=-j$(nproc)
EOF

if [[ $SANITIZER = "address" ]]
then
cat << EOF >> mozconfig
mk_add_options CFLAGS=
mk_add_options CXXFLAGS=
EOF
fi

# Install dependencies. Note that bootstrap installs cargo, which must be added
# to PATH via source. In a successive run (for a different sanitizer), the
# cargo installation carries over, but bootstrap fails if cargo is not in PATH.
export SHELL=/bin/bash
[ -f "$HOME/.cargo/env" ] && source $HOME/.cargo/env
./mach bootstrap --no-interactive --application-choice browser
source $HOME/.cargo/env

# Update internal libFuzzer.
(cd tools/fuzzing/libfuzzer && ./clone_libfuzzer.sh HEAD)

# Build! Takes about 15 minutes on a 32 vCPU instance.
./mach build
./mach gtest buildbutdontrun

# Packages Firefox only to immediately extract the archive. Some files are
# replaced with gtest-variants, which is required by the fuzzing interface.
# Weighs in shy of 1GB afterwards.
make -j$(nproc) -C $OBJDIR package
tar -xf $OBJDIR/dist/firefox*bz2 -C $OUT
mv $OBJDIR/toolkit/library/gtest/libxul.so $OUT/firefox
mv $OUT/firefox/dependentlibs.list $OUT/firefox/dependentlibs.list.gtest

# Get the absolute paths of the required system libraries.
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH:-}:$OUT/firefox
REQUIRED_LIBRARIES=($(ldd $OUT/firefox/libxul.so | gawk '/=> [/]/ {print $3}'))
REQUIRED_LIBRARIES=(${REQUIRED_LIBRARIES[@]##$OUT/*})

# Copy libraries. Less than 50MB total.
mkdir -p $OUT/lib
for REQUIRED_LIBRARY in ${REQUIRED_LIBRARIES[@]}
do
  cp -L $REQUIRED_LIBRARY $OUT/lib
done

# Build a wrapper binary for each target to set environment variables.
for FUZZ_TARGET in ${FUZZ_TARGETS[@]}
do
  $CC $CFLAGS -O0 \
    -DFUZZ_TARGET=$FUZZ_TARGET \
    $SRC/target.c -o $OUT/$FUZZ_TARGET
done

# SdpParser
find media/webrtc -iname "*.sdp" \
  -type f -exec zip -qu $OUT/SdpParser_seed_corpus.zip "{}" \;
cp $SRC/fuzzdata/dicts/sdp.dict $OUT/SdpParser.dict

# StunParser
find media/webrtc -iname "*.stun" \
  -type f -exec zip -qu $OUT/StunParser_seed_corpus.zip "{}" \;
cp $SRC/fuzzdata/dicts/stun.dict $OUT/StunParser.dict

# ContentParentIPC
cp $SRC/fuzzdata/settings/ipc/libfuzzer.content.blacklist.txt $OUT/firefox
cp $SRC/ContentParentIPC.options $OUT

# ContentSecurityPolicyParser
cp dom/security/fuzztest/csp_fuzzer.dict $OUT/ContentSecurityPolicyParser.dict