netsniff-ng: Delete rfmon mac80211 device in case of panic

netsniff-ng does not delete created rfmon device in case of
panic (for example  - bad pcap filter expression), so added ability to
add callback func when panic will be happen and delete rfmon device.

Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

11 files changed, 62 insertions, 9 deletions

diff --git a/astraceroute/Makefile b/astraceroute/Makefile
index 6fd0b17..2e80a11 100644
--- a/astraceroute/Makefile
+++ b/astraceroute/Makefile
@@ -16,6 +16,7 @@ astraceroute-objs =	xmalloc.o \
 			link.o \
 			dev.o \
 			ring.o \
+			die.o \
 			astraceroute.o
 
 ifeq ($(CONFIG_GEOIP), 1)
diff --git a/bpfc/Makefile b/bpfc/Makefile
index 5c8b8c9..b8a3787 100644
--- a/bpfc/Makefile
+++ b/bpfc/Makefile
@@ -5,6 +5,7 @@ bpfc-objs =	xmalloc.o \
 		bpf.o \
 		bpf_lexer.yy.o \
 		bpf_parser.tab.o \
+		die.o \
 		bpfc.o
 
 bpfc-lex =	bpf_lexer.yy.o
diff --git a/curvetun/Makefile b/curvetun/Makefile
index eeebd11..d9ae339 100644
--- a/curvetun/Makefile
+++ b/curvetun/Makefile
@@ -22,6 +22,7 @@ curvetun-objs =	xmalloc.o \
 		ioexact.o \
 		ioops.o \
 		cpusched.o \
+		die.o \
 		curvetun_mgmt_servers.o \
 		curvetun_mgmt_users.o \
 		curvetun_server.o \
diff --git a/die.c b/die.c
new file mode 100644
index 0000000..4c0014d
--- /dev/null
+++ b/die.c
@@ -0,0 +1,31 @@
+/*
+ * Subject to the GPL, version 2.
+ */
+
+#include "xmalloc.h"
+
+struct panic_func {
+	void *arg;
+	void (*on_panic)(void *arg);
+	struct panic_func *next;
+};
+
+static struct panic_func *panic_funcs;
+
+void panic_func_add(void (*on_panic)(void *arg), void *arg)
+{
+	struct panic_func *handler = xmallocz(sizeof(*handler));
+
+	handler->arg		= arg;
+	handler->on_panic	= on_panic;
+	handler->next		= panic_funcs;
+	panic_funcs		= handler;
+};
+
+void call_on_panic_funcs(void)
+{
+	struct panic_func *it;
+
+	for (it = panic_funcs; it; it = it->next)
+		it->on_panic(it->arg);
+}
diff --git a/die.h b/die.h
index 919f3ae..0d709d0 100644
--- a/die.h
+++ b/die.h
@@ -12,6 +12,9 @@
 
 #include "built_in.h"
 
+extern void panic_func_add(void (*on_panic)(void *arg), void *arg);
+extern void call_on_panic_funcs(void);
+
 static inline void panic(const char *format, ...)  __check_format_printf(1, 2);
 static inline void syslog_panic(const char *format,
 				...) __check_format_printf(1, 2);
@@ -20,11 +23,13 @@ static inline void syslog_maybe(bool cond, int priority,
 
 static inline void __noreturn __die_hard(void)
 {
+	call_on_panic_funcs();
 	exit(EXIT_FAILURE);
 }
 
 static inline void __noreturn __die_harder(void)
 {
+	call_on_panic_funcs();
 	_exit(EXIT_FAILURE);
 }
 
diff --git a/flowtop/Makefile b/flowtop/Makefile
index 85acb43..41865c7 100644
--- a/flowtop/Makefile
+++ b/flowtop/Makefile
@@ -21,6 +21,7 @@ flowtop-objs =	xmalloc.o \
 		lookup.o \
 		tprintf.o \
 		screen.o \
+		die.o \
 		flowtop.o
 
 ifeq ($(CONFIG_GEOIP), 1)
diff --git a/ifpps/Makefile b/ifpps/Makefile
index 4d1a9b6..1625ea9 100644
--- a/ifpps/Makefile
+++ b/ifpps/Makefile
@@ -10,6 +10,7 @@ ifpps-objs =	xmalloc.o \
 		dev.o \
 		sig.o \
 		screen.o \
+		die.o \
 		ifpps.o
 
 ifpps-eflags = $(shell pkg-config --cflags ncurses 2> /dev/null)
diff --git a/mausezahn/Makefile b/mausezahn/Makefile
index 7943738..08918b5 100644
--- a/mausezahn/Makefile
+++ b/mausezahn/Makefile
@@ -6,6 +6,8 @@ mausezahn-libs =	-lcli \
 			-lm
 
 mausezahn-objs =	str.o \
+			die.o \
+			xmalloc.o \
 			staging/layer1.o \
 			staging/layer2.o \
 			staging/layer3.o \
diff --git a/netsniff-ng.c b/netsniff-ng.c
index 2eafe31..c0d70c8 100644
--- a/netsniff-ng.c
+++ b/netsniff-ng.c
@@ -184,6 +184,20 @@ static inline bool dump_to_pcap(struct ctx *ctx)
 	return ctx->dump;
 }
 
+static void on_panic_del_rfmon(void *arg)
+{
+	leave_rfmon_mac80211(arg);
+}
+
+static inline void setup_rfmon_mac80211_dev(struct ctx *ctx, char **rfmon_dev)
+{
+	ctx->device_trans = xstrdup(*rfmon_dev);
+	xfree(*rfmon_dev);
+
+	enter_rfmon_mac80211(ctx->device_trans, rfmon_dev);
+	panic_func_add(on_panic_del_rfmon, *rfmon_dev);
+}
+
 static void pcap_to_xmit(struct ctx *ctx)
 {
 	uint8_t *out = NULL;
@@ -227,10 +241,8 @@ static void pcap_to_xmit(struct ctx *ctx)
 	}
 
 	if (ctx->rfraw) {
-		ctx->device_trans = xstrdup(ctx->device_out);
-		xfree(ctx->device_out);
+		setup_rfmon_mac80211_dev(ctx, &ctx->device_out);
 
-		enter_rfmon_mac80211(ctx->device_trans, &ctx->device_out);
 		if (ctx->link_type != LINKTYPE_IEEE802_11 &&
 				ctx->link_type != LINKTYPE_IEEE802_11_RADIOTAP)
 			panic("Wrong linktype of pcap!\n");
@@ -1464,12 +1476,8 @@ int main(int argc, char **argv)
 	}
 
 	if (device_mtu(ctx.device_in) || !strncmp("any", ctx.device_in, strlen(ctx.device_in))) {
-		if (ctx.rfraw) {
-			ctx.device_trans = xstrdup(ctx.device_in);
-			xfree(ctx.device_in);
-
-			enter_rfmon_mac80211(ctx.device_trans, &ctx.device_in);
-		}
+		if (ctx.rfraw)
+			setup_rfmon_mac80211_dev(&ctx, &ctx.device_in);
 
 		ctx.link_type = pcap_devtype_to_linktype(ctx.device_in);
 
diff --git a/netsniff-ng/Makefile b/netsniff-ng/Makefile
index bc5e032..63bf58f 100644
--- a/netsniff-ng/Makefile
+++ b/netsniff-ng/Makefile
@@ -63,6 +63,7 @@ netsniff-ng-objs =	dissector.o \
 			tprintf.o \
 			timer.o \
 			mac80211.o \
+			die.o \
 			netsniff-ng.o
 
 ifeq ($(CONFIG_LIBPCAP), 1)
diff --git a/trafgen/Makefile b/trafgen/Makefile
index d395b16..b37e62d 100644
--- a/trafgen/Makefile
+++ b/trafgen/Makefile
@@ -3,6 +3,7 @@ trafgen-libs =	$(shell pkg-config --libs libnl-3.0) \
 		-lm
 
 trafgen-objs =	xmalloc.o \
+		die.o \
 		ioops.o \
 		privs.o \
 		proc.o \