tests: New style fuzzing tool for wpa_supplicant WNM handling

This is a newer version of tests/wnm-fuzzer tool as the initial step in
creating a more uniform set of fuzzing tools that can be used with both
libFuzzer and afl-fuzz.

Signed-off-by: Jouni Malinen <j@w1.fi>

tests/fuzzing/README

@@ -0,0 +1,23 @@
+hostap.git fuzz testing
+-----------------------
+
+These tools can be used for fuzz testing of various components used
+within wpa_supplicant and hostapd. Each directory contains a fuzzing
+tool that focuses on one input handler. Each tool can be compiled either
+to work with the libFuzzer or as a separate tool that reads the input
+from a file specified on the command line, e.g., for American fuzzy lop
+(afl-fuzz). Example test corpus is included in */corpus directory.
+
+Example fuzzing with libFuzzer
+
+cd @TOOL@
+make clean
+make LIBFUZZER=y
+./@TOOL@ corpus
+
+Example fuzzing with afl-fuzz
+
+cd @TOOL@
+make clean
+CC=afl-gcc make
+afl-fuzz -i corpus -o findings -- $PWD/@TOOL@ @@

tests/fuzzing/fuzzer-common.c

@@ -0,0 +1,56 @@
+/*
+ * Common helper functions for fuzzing tools
+ * Copyright (c) 2019, Jouni Malinen <j@w1.fi>
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+
+#include "utils/includes.h"
+
+#include "utils/common.h"
+
+
+void wpa_fuzzer_set_debug_level(void)
+{
+	static int first = 1;
+
+	if (first) {
+		char *env;
+
+		first = 0;
+		env = getenv("WPADEBUG");
+		if (env)
+			wpa_debug_level = atoi(env);
+		else
+			wpa_debug_level = MSG_ERROR + 1;
+
+		wpa_debug_show_keys = 1;
+	}
+}
+
+
+#ifndef TEST_LIBFUZZER
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
+
+int main(int argc, char *argv[])
+{
+	char *data;
+	size_t len;
+
+	if (argc < 2) {
+		printf("usage: %s <file>\n", argv[0]);
+		return -1;
+	}
+
+	data = os_readfile(argv[1], &len);
+	if (!data) {
+		printf("Could not read '%s'\n", argv[1]);
+		return -1;
+	}
+
+	LLVMFuzzerTestOneInput((const uint8_t *) data, len);
+	os_free(data);
+	return 0;
+}
+#endif /* !TEST_LIBFUZZER */

tests/fuzzing/fuzzer-common.h

@@ -0,0 +1,14 @@
+/*
+ * Common helper functions for fuzzing tools
+ * Copyright (c) 2019, Jouni Malinen <j@w1.fi>
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+
+#ifndef FUZZER_COMMON_H
+#define FUZZER_COMMON_H
+
+void wpa_fuzzer_set_debug_level(void);
+
+#endif /* FUZZER_COMMON_H */

tests/fuzzing/rules.include

@@ -0,0 +1,88 @@
+ifdef LIBFUZZER
+CC=clang
+CFLAGS = -MMD -O2 -Wall -g
+CFLAGS += -fsanitize=fuzzer,address,signed-integer-overflow,unsigned-integer-overflow
+CFLAGS += -DTEST_LIBFUZZER
+LDFLAGS += -fsanitize=fuzzer,address,signed-integer-overflow,unsigned-integer-overflow
+endif
+
+ifndef CC
+CC=gcc
+endif
+
+ifndef LDO
+LDO=$(CC)
+endif
+
+ifndef CFLAGS
+CFLAGS = -MMD -O2 -Wall -g
+endif
+
+CFLAGS += -DCONFIG_NO_RANDOM_POOL
+CFLAGS += -DTEST_FUZZ
+
+WPAS_SRC=../../../wpa_supplicant
+SRC=../../../src
+
+CFLAGS += -I$(SRC) -I$(SRC)/utils -I$(WPAS_SRC)
+OBJS += ../fuzzer-common.o
+
+$(SRC)/ap/libap.a:
+	$(MAKE) -C $(SRC)/ap TEST_FUZZ=y
+
+$(SRC)/common/libcommon.a:
+	$(MAKE) -C $(SRC)/common
+
+$(SRC)/crypto/libcrypto.a:
+	$(MAKE) -C $(SRC)/crypto
+
+$(SRC)/eapol_auth/libeapol_auth.a:
+	$(MAKE) -C $(SRC)/eapol_auth
+
+$(SRC)/eapol_supp/libeapol_supp.a:
+	$(MAKE) -C $(SRC)/eapol_supp
+
+$(SRC)/eap_common/libeap_common.a:
+	$(MAKE) -C $(SRC)/eap_common
+
+$(SRC)/eap_peer/libeap_peer.a:
+	$(MAKE) -C $(SRC)/eap_peer
+
+$(SRC)/eap_server/libeap_server.a:
+	$(MAKE) -C $(SRC)/eap_server
+
+$(SRC)/l2_packet/libl2_packet.a:
+	$(MAKE) -C $(SRC)/l2_packet
+
+$(SRC)/p2p/libp2p.a:
+	$(MAKE) -C $(SRC)/p2p
+
+$(SRC)/radius/libradius.a:
+	$(MAKE) -C $(SRC)/radius
+
+$(SRC)/rsn_supp/librsn_supp.a:
+	$(MAKE) -C $(SRC)/rsn_supp TEST_FUZZ=y
+
+$(SRC)/tls/libtls.a:
+	$(MAKE) -C $(SRC)/tls TEST_FUZZ=y
+
+$(SRC)/utils/libutils.a:
+	$(MAKE) -C $(SRC)/utils TEST_FUZZ=y
+
+$(SRC)/wps/libwps.a:
+	$(MAKE) -C $(SRC)/wps
+
+Q=@
+E=echo
+ifeq ($(V), 1)
+Q=
+E=true
+endif
+ifeq ($(QUIET), 1)
+Q=@
+E=true
+endif
+
+%.o: %.c
+	$(Q)$(CC) -c -o $@ $(CFLAGS) $<
+	@$(E) "  CC " $<

tests/fuzzing/wnm/Makefile

@@ -0,0 +1,52 @@
+all: wnm
+include ../rules.include
+
+CFLAGS += -DCONFIG_WNM
+CFLAGS += -DCONFIG_INTERWORKING
+CFLAGS += -DCONFIG_GAS
+CFLAGS += -DCONFIG_HS20
+CFLAGS += -DIEEE8021X_EAPOL
+
+LIBS += $(SRC)/common/libcommon.a
+LIBS += $(SRC)/crypto/libcrypto.a
+LIBS += $(SRC)/tls/libtls.a
+LIBS += $(SRC)/rsn_supp/librsn_supp.a
+LIBS += $(SRC)/eapol_supp/libeapol_supp.a
+LIBS += $(SRC)/eap_peer/libeap_peer.a
+LIBS += $(SRC)/eap_common/libeap_common.a
+LIBS += $(SRC)/l2_packet/libl2_packet.a
+LIBS += $(SRC)/utils/libutils.a
+
+ELIBS += $(SRC)/crypto/libcrypto.a
+ELIBS += $(SRC)/tls/libtls.a
+
+OBJS += $(WPAS_SRC)/blacklist.o
+OBJS += $(WPAS_SRC)/bss.o
+OBJS += $(WPAS_SRC)/config.o
+OBJS += $(WPAS_SRC)/config_file.o
+OBJS += $(WPAS_SRC)/eap_register.o
+OBJS += $(WPAS_SRC)/events.o
+OBJS += $(WPAS_SRC)/gas_query.o
+OBJS += $(WPAS_SRC)/hs20_supplicant.o
+OBJS += $(WPAS_SRC)/interworking.o
+OBJS += $(WPAS_SRC)/notify.o
+OBJS += $(WPAS_SRC)/offchannel.o
+OBJS += $(WPAS_SRC)/op_classes.o
+OBJS += $(WPAS_SRC)/rrm.o
+OBJS += $(WPAS_SRC)/scan.o
+OBJS += $(WPAS_SRC)/wmm_ac.o
+OBJS += $(WPAS_SRC)/wnm_sta.o
+OBJS += $(WPAS_SRC)/wpa_supplicant.o
+OBJS += $(WPAS_SRC)/wpas_glue.o
+OBJS += $(SRC)/drivers/driver_common.o
+OBJS += $(SRC)/drivers/drivers.o
+
+wnm: wnm.o $(OBJS) $(LIBS)
+	$(LDO) $(LDFLAGS) -o $@ $^ $(LIBS) $(ELIBS)
+
+clean:
+	$(MAKE) -C $(SRC) clean
+	$(MAKE) -C $(WPAS_SRC) clean
+	rm -f wnm *~ *.o *.d ../*~ ../*.o ../*.d
+
+-include $(OBJS:%.o=%.d)

tests/fuzzing/wnm/wnm.c

@@ -0,0 +1,99 @@
+/*
+ * wpa_supplicant - WNM fuzzer
+ * Copyright (c) 2015-2019, Jouni Malinen <j@w1.fi>
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+
+#include "utils/includes.h"
+
+#include "utils/common.h"
+#include "utils/eloop.h"
+#include "common/ieee802_11_defs.h"
+#include "rsn_supp/wpa.h"
+#include "rsn_supp/wpa_i.h"
+#include "wpa_supplicant_i.h"
+#include "bss.h"
+#include "wnm_sta.h"
+#include "config.h"
+#include "../fuzzer-common.h"
+
+
+struct arg_ctx {
+	const u8 *data;
+	size_t data_len;
+	struct wpa_supplicant wpa_s;
+	struct wpa_bss bss;
+	struct wpa_driver_ops driver;
+	struct wpa_sm wpa;
+	struct wpa_config conf;
+};
+
+
+static void test_send_wnm(void *eloop_data, void *user_ctx)
+{
+	struct arg_ctx *ctx = eloop_data;
+	const struct ieee80211_mgmt *mgmt;
+
+	wpa_hexdump(MSG_MSGDUMP, "fuzzer - WNM", ctx->data, ctx->data_len);
+
+	mgmt = (const struct ieee80211_mgmt *) ctx->data;
+	ieee802_11_rx_wnm_action(&ctx->wpa_s, mgmt, ctx->data_len);
+
+	eloop_terminate();
+}
+
+
+static int init_wpa(struct arg_ctx *ctx)
+{
+	ctx->wpa_s.wpa_state = WPA_COMPLETED;
+	os_memcpy(ctx->wpa_s.bssid, "\x02\x00\x00\x00\x03\x00", ETH_ALEN);
+	ctx->wpa_s.current_bss = &ctx->bss;
+	ctx->wpa_s.driver = &ctx->driver;
+	ctx->wpa_s.wpa = &ctx->wpa;
+	ctx->wpa_s.conf = &ctx->conf;
+
+	return 0;
+}
+
+
+static void deinit_wpa(struct arg_ctx *ctx)
+{
+	wnm_deallocate_memory(&ctx->wpa_s);
+}
+
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+{
+	struct arg_ctx ctx;
+
+	wpa_fuzzer_set_debug_level();
+
+	if (os_program_init())
+		return 0;
+
+	if (eloop_init()) {
+		wpa_printf(MSG_ERROR, "Failed to initialize event loop");
+		return 0;
+	}
+
+	os_memset(&ctx, 0, sizeof(ctx));
+	ctx.data = data;
+	ctx.data_len = size;
+	if (init_wpa(&ctx))
+		goto fail;
+
+	eloop_register_timeout(0, 0, test_send_wnm, &ctx, NULL);
+
+	wpa_printf(MSG_DEBUG, "Starting eloop");
+	eloop_run();
+	wpa_printf(MSG_DEBUG, "eloop done");
+	deinit_wpa(&ctx);
+
+fail:
+	eloop_destroy();
+	os_program_deinit();
+
+	return 0;
+}