Add a basic fuzzing framework using libFuzzer

Updates #1

fuzz

@@ -0,0 +1,18 @@
+#!/bin/sh
+# I'm not sure how to make maximum use of this invention
+# Make sure to have llvm-symbolizer installed
+clang -g -fsanitize=address,undefined,fuzzer -fno-sanitize-recover=all \
+	tests/fuzz.c -o fuzz-executor
+
+fuzz () {
+	echo "`tput bold`-- Fuzzing $1`tput sgr0`"
+	mkdir -p /tmp/corpus-$1
+	./fuzz-executor -test=$1 -artifact_prefix=$1- \
+		-max_len=32 -max_total_time=600 -timeout=1 /tmp/corpus-$1
+}
+
+if [ $# -gt 0 ]; then
+	for test in "$@"; do fuzz $test; done
+else
+	for test in $(./fuzz-executor); do fuzz $test; done
+fi

tests/fuzz.c

@@ -0,0 +1,210 @@
+/*
+ * tests/fuzz.c
+ *
+ * Copyright (c) 2020, Přemysl Eric Janouch <p@janouch.name>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#define PROGRAM_NAME "fuzz"
+#define PROGRAM_VERSION "0"
+
+#define LIBERTY_WANT_SSL
+// The MPD client is a full wrapper and needs the network
+#define LIBERTY_WANT_POLLER
+#define LIBERTY_WANT_ASYNC
+
+#define LIBERTY_WANT_PROTO_IRC
+#define LIBERTY_WANT_PROTO_HTTP
+#define LIBERTY_WANT_PROTO_SCGI
+#define LIBERTY_WANT_PROTO_FASTCGI
+#define LIBERTY_WANT_PROTO_WS
+#define LIBERTY_WANT_PROTO_MPD
+
+#include "../liberty.c"
+
+// --- UTF-8 -------------------------------------------------------------------
+
+static void
+test_utf8_validate (const uint8_t *data, size_t size)
+{
+	utf8_validate ((const char *) data, size);
+}
+
+// --- Base 64 -----------------------------------------------------------------
+
+static void
+test_base64_decode (const uint8_t *data, size_t size)
+{
+	struct str out = str_make ();
+	base64_decode ((const char *) data, size, &out);
+	str_free (&out);
+}
+
+// --- IRC ---------------------------------------------------------------------
+
+static void
+test_irc_parse_message (const uint8_t *data, size_t size)
+{
+	struct str wrap = str_make ();
+	str_append_data (&wrap, data, size);
+
+	struct irc_message msg;
+	irc_parse_message (&msg, wrap.str);
+	irc_free_message (&msg);
+
+	str_free (&wrap);
+}
+
+// --- HTTP --------------------------------------------------------------------
+
+static void
+test_http_parse_media_type (const uint8_t *data, size_t size)
+{
+	struct str wrap = str_make ();
+	str_append_data (&wrap, data, size);
+
+	char *type = NULL;
+	char *subtype = NULL;
+	struct str_map parameters = str_map_make (free);
+	http_parse_media_type (wrap.str, &type, &subtype, &parameters);
+	free (type);
+	free (subtype);
+	str_map_free (&parameters);
+
+	str_free (&wrap);
+}
+
+static void
+test_http_parse_upgrade (const uint8_t *data, size_t size)
+{
+	struct str wrap = str_make ();
+	str_append_data (&wrap, data, size);
+
+	struct http_protocol *protocols = NULL;
+	http_parse_upgrade (wrap.str, &protocols);
+	LIST_FOR_EACH (struct http_protocol, iter, protocols)
+		http_protocol_destroy (iter);
+
+	str_free (&wrap);
+}
+
+// --- SCGI --------------------------------------------------------------------
+
+static bool
+test_scgi_parser_on_headers_read (void *user_data)
+{
+	(void) user_data;
+	return true;
+}
+
+static bool
+test_scgi_parser_on_content (void *user_data, const void *data, size_t len)
+{
+	(void) user_data;
+	(void) data;
+	(void) len;
+	return true;
+}
+
+static void
+test_scgi_parser_push (const uint8_t *data, size_t size)
+{
+	struct scgi_parser parser = scgi_parser_make ();
+	parser.on_headers_read = test_scgi_parser_on_headers_read;
+	parser.on_content      = test_scgi_parser_on_content;
+
+	scgi_parser_push (&parser, data, size, NULL);
+	scgi_parser_free (&parser);
+}
+
+// --- WebSockets --------------------------------------------------------------
+
+static bool
+test_websockets_on_frame_header (void *user_data, const struct ws_parser *self)
+{
+	(void) user_data;
+	(void) self;
+	return true;
+}
+
+static bool
+test_websockets_on_frame (void *user_data, const struct ws_parser *self)
+{
+	(void) user_data;
+	(void) self;
+	return true;
+}
+
+static void
+test_ws_parser_push (const uint8_t *data, size_t size)
+{
+	struct ws_parser parser = ws_parser_make ();
+	parser.on_frame_header = test_websockets_on_frame_header;
+	parser.on_frame        = test_websockets_on_frame;
+
+	ws_parser_push (&parser, data, size);
+	ws_parser_free (&parser);
+}
+
+// --- Main --------------------------------------------------------------------
+
+typedef void (*fuzz_test_fn) (const uint8_t *data, size_t size);
+static fuzz_test_fn generator = NULL;
+
+void
+LLVMFuzzerTestOneInput (const uint8_t *data, size_t size)
+{
+	generator (data, size);
+}
+
+int
+LLVMFuzzerInitialize (int *argcp, char ***argvp)
+{
+	struct str_map targets = str_map_make (NULL);
+#define REGISTER(name) str_map_set (&targets, #name, test_ ## name);
+	REGISTER (utf8_validate)
+	REGISTER (base64_decode)
+	REGISTER (irc_parse_message)
+	REGISTER (http_parse_media_type)
+	REGISTER (http_parse_upgrade)
+	REGISTER (scgi_parser_push)
+	REGISTER (ws_parser_push)
+	// TODO: add more parsers/processors
+
+	char **argv = *argvp, *option = "-test=", *name = NULL;
+	for (int i = 1; i < *argcp; i++)
+		if (!strncmp (argv[i], option, strlen (option)))
+		{
+			name = argv[i] + strlen (option);
+			memmove (argv + i, argv + i + 1, (*argcp - i) * sizeof *argv);
+			(*argcp)--;
+		}
+
+	if (!name)
+	{
+		struct str_map_iter iter = str_map_iter_make (&targets);
+		while (str_map_iter_next (&iter))
+			printf ("%s\n", iter.link->key);
+		exit (EXIT_FAILURE);
+	}
+
+	if (!(generator = str_map_find (&targets, name)))
+	{
+		fprintf (stderr, "Unknown test: %s\n", name);
+		exit (EXIT_FAILURE);
+	}
+
+	str_map_free (&targets);
+	return 0;
+}

tests/proto.c

@@ -77,7 +77,7 @@ test_irc (void)
 static void
 test_http_parser (void)
 {
-	struct str_map parameters = str_map_make (NULL);
+	struct str_map parameters = str_map_make (free);
 	parameters.key_xfrm = tolower_ascii_strxfrm;
 
 	char *type = NULL;
@@ -88,9 +88,11 @@ test_http_parser (void)
 	soft_assert (!strcasecmp_ascii (subtype, "html"));
 	soft_assert (parameters.len == 1);
 	soft_assert (!strcmp (str_map_find (&parameters, "charset"), "utf-8"));
+	free (type);
+	free (subtype);
 	str_map_free (&parameters);
 
-	struct http_protocol *protocols;
+	struct http_protocol *protocols = NULL;
 	soft_assert (http_parse_upgrade ("websocket, HTTP/2.0, , ", &protocols));
 
 	soft_assert (!strcmp (protocols->name, "websocket"));