1 files changed, 112 insertions, 0 deletions
diff --git a/tests/fuzz/crypt2_load_fuzz.cc b/tests/fuzz/crypt2_load_fuzz.cc
new file mode 100644
index 0000000..1251d72
--- /dev/null
+++ b/tests/fuzz/crypt2_load_fuzz.cc
@@ -0,0 +1,112 @@
+/*
+ * cryptsetup LUKS2 fuzz target
+ *
+ * Copyright (C) 2022-2023 Daniel Zatovic <daniel.zatovic@gmail.com>
+ * Copyright (C) 2022-2023 Red Hat, Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+extern "C" {
+#define FILESIZE (16777216)
+#include "src/cryptsetup.h"
+#include <err.h>
+#include "luks2/luks2.h"
+#include "crypto_backend/crypto_backend.h"
+#include "FuzzerInterface.h"
+
+static int calculate_checksum(const uint8_t* data, size_t size) {
+	struct crypt_hash *hd = NULL;
+	struct luks2_hdr_disk *hdr = NULL;
+	int hash_size;
+	uint64_t hdr_size1, hdr_size2;
+	int r = 0;
+
+	/* primary header */
+	if (sizeof(struct luks2_hdr_disk) > size)
+		return 0;
+	hdr = CONST_CAST(struct luks2_hdr_disk *) data;
+
+	hdr_size1 = be64_to_cpu(hdr->hdr_size);
+	if (hdr_size1 > size)
+		return 0;
+	memset(&hdr->csum, 0, LUKS2_CHECKSUM_L);
+	if ((r = crypt_hash_init(&hd, "sha256")))
+		goto out;
+	if ((r = crypt_hash_write(hd, CONST_CAST(char*) data, hdr_size1)))
+		goto out;
+	hash_size = crypt_hash_size("sha256");
+	if (hash_size <= 0) {
+		r = 1;
+		goto out;
+	}
+	if ((r = crypt_hash_final(hd, (char*)&hdr->csum, (size_t)hash_size)))
+		goto out;
+	crypt_hash_destroy(hd);
+
+	/* secondary header */
+	if (hdr_size1 < sizeof(struct luks2_hdr_disk))
+		hdr_size1 = sizeof(struct luks2_hdr_disk);
+
+	if (hdr_size1 + sizeof(struct luks2_hdr_disk) > size)
+		return 0;
+	hdr = CONST_CAST(struct luks2_hdr_disk *) (data + hdr_size1);
+
+	hdr_size2 = be64_to_cpu(hdr->hdr_size);
+	if (hdr_size2 > size || (hdr_size1 + hdr_size2) > size)
+		return 0;
+
+	memset(&hdr->csum, 0, LUKS2_CHECKSUM_L);
+	if ((r = crypt_hash_init(&hd, "sha256")))
+		goto out;
+	if ((r = crypt_hash_write(hd, (char*) hdr, hdr_size2)))
+		goto out;
+	if ((r = crypt_hash_final(hd, (char*)&hdr->csum, (size_t)hash_size)))
+		goto out;
+
+out:
+	if (hd)
+		crypt_hash_destroy(hd);
+	return r;
+}
+
+int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+	int fd;
+	struct crypt_device *cd = NULL;
+	char name[] = "/tmp/test-script-fuzz.XXXXXX";
+
+	if (calculate_checksum(data, size))
+		return 0;
+
+	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;
+
+	if (crypt_init(&cd, name) == 0)
+		(void)crypt_load(cd, CRYPT_LUKS2, NULL);
+	crypt_free(cd);
+out:
+	close(fd);
+	unlink(name);
+	return 0;
+}
+}