oss-fuzz: Improve interaction with fuzzing tools and add new tests in fuzz/ directory

fuzz/main.c

@@ -0,0 +1,140 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/stat.h>
+
+#include "fuzz.h"
+
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+
+#include <dirent.h>
+
+static void test_all_from(const char *dirname)
+{
+	DIR *dirp;
+	struct dirent *dp;
+
+	dirp = opendir(dirname);
+	if (dirp == NULL) {
+		return;
+	}
+
+	while ((dp = readdir(dirp)) != NULL) {
+		char filename[strlen(dirname) + strlen(dp->d_name) + 2];
+		int fd;
+		struct stat st;
+		char *data;
+		ssize_t n;
+
+		if (dp->d_name[0] == '.') {
+			continue;
+		}
+		snprintf(filename, sizeof(filename), "%s/%s",
+			 dirname, dp->d_name);
+
+		if ((fd = open(filename, O_RDONLY)) == -1) {
+			fprintf(stderr, "Failed to open %s: %s\n", filename,
+				strerror(errno));
+			continue;
+		}
+
+		if (fstat(fd, &st) != 0) {
+			fprintf(stderr, "Failed to stat %s: %s\n", filename,
+				strerror(errno));
+			goto closefd;
+		}
+
+		data = malloc(st.st_size);
+		n = read(fd, data, st.st_size);
+		if (n == st.st_size) {
+			printf("testing %zd bytes from %s\n",
+			       n, filename);
+			fflush(stdout);
+			LLVMFuzzerTestOneInput((const uint8_t *)data, n);
+			fflush(stderr);
+		} else {
+			if (n < 0) {
+				fprintf(stderr,
+					"Failed to read %zd bytes from %s: %s\n",
+					(ssize_t) st.st_size, filename,
+					strerror(errno));
+			} else {
+				fprintf(stderr,
+					"Failed to read %zd bytes from %s"
+					", got %zd\n",
+					(ssize_t) st.st_size, filename,
+					n);
+			}
+		}
+		free(data);
+	closefd:
+		close(fd);
+	}
+
+	closedir(dirp);
+}
+
+int main(int argc, char **argv)
+{
+	char corpusdir[PATH_MAX];
+	const char *target = strrchr(argv[0], '/');
+
+	UNUSED(argc);
+	UNUSED(argv);
+
+	target = target ? target + 1 : argv[0];
+	if (strncmp(target, "lt-", 3) == 0) {
+		target += 3;
+	}
+
+	snprintf(corpusdir, sizeof(corpusdir), FUZZDIR "/%s.in", target);
+
+	test_all_from(corpusdir);
+
+	return 0;
+}
+
+#elif __AFL_COMPILER
+
+int main(int argc, char **argv)
+{
+	int ret;
+	unsigned char buf[64 * 1024];
+
+	UNUSED(argc);
+	UNUSED(argv);
+
+#ifdef __AFL_LOOP
+	while (__AFL_LOOP(10000)) { // only works with afl-clang-fast
+#else
+	{
+#endif
+		ret = fread(buf, 1, sizeof(buf), stdin);
+		if (ret < 0) {
+			return 0;
+		}
+
+		LLVMFuzzerTestOneInput(buf, ret);
+	}
+
+	return 0;
+}
+
+#endif /* FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION */