OSS-Fuzz: Add new fuzzer targets general crypto loading

Signed-off-by: Arthur Chan <arthur.chan@adalogics.com>

Author: arthurscchan

tests/fuzz/Makefile.am

@@ -4,7 +4,7 @@ distclean-local:
 	-rm -rf out build
 
 if ENABLE_FUZZ_TARGETS
-EXTRA_PROGRAMS  = crypt2_load_fuzz crypt2_load_ondisk_fuzz
+EXTRA_PROGRAMS  = crypt2_load_fuzz crypt2_load_ondisk_fuzz crypt_load_misc_fuzz
 CLEANFILES = $(EXTRA_PROGRAMS)
 
 LIB_FUZZING_ENGINE := $(if $(LIB_FUZZING_ENGINE),$(LIB_FUZZING_ENGINE),"-fsanitize=fuzzer")
@@ -22,6 +22,11 @@ crypt2_load_ondisk_fuzz_LDADD  = ../../libcryptsetup.la -L$(DEPS_PATH)/lib
 crypt2_load_ondisk_fuzz_LDFLAGS = $(AM_LDFLAGS) $(LIB_FUZZING_ENGINE) $(SANITIZER)
 crypt2_load_ondisk_fuzz_CXXFLAGS = $(AM_CXXFLAGS) -I$(top_srcdir)/lib -I$(top_srcdir)/tests/fuzz
 
+crypt_load_misc_fuzz_SOURCES = FuzzerInterface.h crypt_load_misc_fuzz.cc
+crypt_load_misc_fuzz_LDADD  = ../../libcryptsetup.la -L$(DEPS_PATH)/lib
+crypt_load_misc_fuzz_LDFLAGS = $(AM_LDFLAGS) $(LIB_FUZZING_ENGINE) $(SANITIZER)
+crypt_load_misc_fuzz_CXXFLAGS = $(AM_CXXFLAGS) -I$(top_srcdir)/lib -I$(top_srcdir)/tests/fuzz
+
 test-environment-m:
 	@ if test ! -d $(DEPS_PATH); then \
 		echo "You need to build static libraries first; use oss-fuzz-build.sh script."; \

tests/fuzz/crypt_load_misc_fuzz.cc

@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * cryptsetup VERITY, INTEGRITY fuzz target
+ */
+
+extern "C" {
+#define FILESIZE (16777216)
+#include "src/cryptsetup.h"
+#include <err.h>
+#include "verity/verity.h"
+#include "integrity/integrity.h"
+#include "crypto_backend/crypto_backend.h"
+#include "FuzzerInterface.h"
+
+static void empty_log(int level, const char *msg, void *usrptr) {}
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+	int fd, r;
+	struct crypt_device *cd = NULL;
+	char name[] = "/tmp/test-script-fuzz.XXXXXX";
+
+	fd = mkostemp(name, O_RDWR | O_CREAT | O_EXCL | O_CLOEXEC);
+	if (fd == -1)
+		err(EXIT_FAILURE, "mkostemp() failed");
+
+	/* enlarge header */
+	if (ftruncate(fd, FILESIZE) == -1)
+		goto out;
+
+	if (write_buffer(fd, data, size) != (ssize_t) size)
+		goto out;
+
+	crypt_set_log_callback(NULL, empty_log, NULL);
+
+	if (crypt_init(&cd, name) == 0) {
+		r = crypt_load(cd, CRYPT_VERITY, NULL);
+		if (r == 0)
+			goto out;
+
+		(void) crypt_load(cd, CRYPT_INTEGRITY, NULL);
+	}
+out:
+	crypt_free(cd);
+	close(fd);
+	unlink(name);
+	return 0;
+}
+}

tests/fuzz/meson.build

@@ -34,4 +34,22 @@ if get_option('fuzz-targets')
             link_args,
         ],
         include_directories: includes_tools)
+
+    crypt_load_misc_fuzz = executable('crypt_load_misc_fuzz',
+        [
+            'crypt_load_misc_fuzz.cc',
+        ],
+        dependencies: [
+            devmapper,
+            fuzzing_engine,
+        ],
+        link_with: [
+            libcryptsetup,
+            libcrypto_backend,
+            libutils_io,
+        ],
+        link_args: [
+            link_args,
+        ],
+        include_directories: includes_tools)
 endif

tests/fuzz/oss-fuzz-build.sh

@@ -34,7 +34,7 @@ export CFLAGS="${CFLAGS:-$flags} -I$DEPS_PATH/include"
 export CXXFLAGS="${CXXFLAGS:-$flags} -I$DEPS_PATH/include"
 export LDFLAGS="${LDFLAGS-} -L$DEPS_PATH/lib"
 
-ENABLED_FUZZERS=${ENABLED_FUZZERS:-crypt2_load_fuzz crypt2_load_ondisk_fuzz}
+ENABLED_FUZZERS=${ENABLED_FUZZERS:-crypt2_load_fuzz crypt2_load_ondisk_fuzz crypt_load_misc_fuzz}
 
 mkdir -p $SRC
 mkdir -p $OUT