oss-fuzz: Port the test suite script from google/oss-fuzz

This allows us to more easily manage oss-fuzz failures on OpenSIPS
project side, without requiring an oss-fuzz PR on each build or
test-related change.

Makefile.defs

@@ -1696,7 +1696,7 @@ endif
 ifeq (1,$(shell grep -c '^\DEFS+= -DUNIT_TESTS' $(TOP_SRCDIR)/Makefile.conf))
 DEFS := $(DEFS) -DUNIT_TESTS
 LIBS := $(LIBS) -ltap
-test_src := $(shell find . -wholename "*/test/*\.c" | grep -v "^./modules/")
+test_src := $(shell find . -wholename "*/test/*\.c" | grep -vE "^./(modules|test/fuzz)/")
 test_objs := $(test_src:.c=.o)
 objs := $(objs) $(test_objs)
 endif

test/fuzz/oss-fuzz-build.sh

@@ -0,0 +1,45 @@
+#!/bin/bash -eu
+# Copyright 2022 OpenSIPS Solutions
+# Copyright 2021 Google LLC
+#
+# 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.
+#
+################################################################################
+
+# disable all custom memory allocators, use system malloc instead
+sed -i '
+  s/^#\?\(DEFS+= -DPKG_MALLOC\)/DEFS+= -DSYSTEM_MALLOC/g
+  s/^\(DEFS+= -DUSE_MCAST\)/#\1/g
+  s/^\(DEFS+= -DF_MALLOC\)/#\1/g
+  s/^\(DEFS+= -DQ_MALLOC\)/#\1/g
+  s/^\(DEFS+= -DHP_MALLOC\)/#\1/g
+  s/^\(DEFS+= -DDBG_MALLOC\)/#\1/g
+  s/^\(DEFS+= -DDBG_MALLOC\)/#\1/g
+  s/^#\(DEFS+= -DFUZZ_BUILD\)/\1/g
+  ' Makefile.conf.template
+
+# disable update_stat() calls in the parser, since they rely on SHM
+sed -i '/update_stat.*bad_URIs/d' parser/parse_uri.c
+sed -i '/update_stat.*bad_msg_hdr/d' parser/msg_parser.c
+
+cp ./test/fuzz/fuzz_*.c ./parser/
+
+make static
+
+rm main.o
+mkdir objects && find . -name "*.o" -exec cp {} ./objects/ \;
+ar -r libopensips.a ./objects/*.o
+
+$CC $CFLAGS $LIB_FUZZING_ENGINE ./parser/fuzz_msg_parser.o ./libopensips.a  -ldl -lresolv -o $OUT/fuzz_msg_parser
+$CC $CFLAGS $LIB_FUZZING_ENGINE ./parser/fuzz_uri_parser.o ./libopensips.a  -ldl -lresolv -o $OUT/fuzz_uri_parser
+$CC $CFLAGS $LIB_FUZZING_ENGINE ./parser/fuzz_csv_parser.o ./libopensips.a  -ldl -lresolv -o $OUT/fuzz_csv_parser