syscall symbol loading fixes, makefile SDK_DEBUG tweak

make-linux.mk

@@ -64,7 +64,7 @@ endif
 # Debug output for Network Containers
 # Specific levels can be controlled in netcon/common.inc.c
 ifeq ($(SDK_DEBUG),1)
-	DEFS+=-DSDK_DEBUG
+	DEFS+=-DSDK_DEBUG -g
 endif
 
 # Uncomment for gprof profile build
@@ -84,7 +84,7 @@ linux_shared_lib: remove_only_intermediates $(OBJS)
 	# Build liblwip.so which must be placed in ZT home for zerotier-netcon-service to work
 	make -f make-liblwip.mk
 	# Use gcc not clang to build standalone intercept library since gcc is typically used for libc and we want to ensure maximal ABI compatibility
-	cd src ; gcc $(DEFS) -g -O2 -Wall -std=c99 -fPIC -DVERBOSE -D_GNU_SOURCE -DSDK_INTERCEPT -I. -I../zerotierone/node -nostdlib -shared -o libztintercept.so SDK_Sockets.c SDK_Intercept.c SDK_Debug.c SDK_RPC.c -ldl
+	cd src ; gcc $(DEFS) -O2 -Wall -std=c99 -fPIC -DVERBOSE -D_GNU_SOURCE -DSDK_INTERCEPT -I. -I../zerotierone/node -nostdlib -shared -o libztintercept.so SDK_Sockets.c SDK_Intercept.c SDK_Debug.c SDK_RPC.c -ldl
 	cp src/libztintercept.so build/linux_shared_lib/libztintercept.so
 	ln -sf zerotier-sdk-service zerotier-cli
 	ln -sf zerotier-sdk-service zerotier-idtool

make-mac.mk

@@ -45,7 +45,7 @@ endif
 # Debug output for SDK
 # Specific levels can be controlled in src/debug.h
 ifeq ($(SDK_DEBUG),1)
-	DEFS+=-DSDK_DEBUG
+	DEFS+=-DSDK_DEBUG -g
 endif
 
 CXXFLAGS=$(CFLAGS) -fno-rtti

src/SDK.h

@@ -43,28 +43,28 @@ void zt_init_rpc(char *path, char *nwid);
 extern char *api_netpath;
 
 #if defined(__linux__)
-	static int (*realaccept4)(ACCEPT4_SIG) = 0;
+	extern int (*realaccept4)(ACCEPT4_SIG);
 	#if !defined(__ANDROID__)
-		static int (*realsyscall)(SYSCALL_SIG) = 0;
+		extern int (*realsyscall)(SYSCALL_SIG);
 	#endif
 #endif
 
 #if !defined(__ANDROID__)
     bool check_intercept_enabled_for_thread();
-	static int (*realbind)(BIND_SIG) = 0;
-	static int (*realsendmsg)(SENDMSG_SIG) = 0;
-	static ssize_t (*realsendto)(SENDTO_SIG) = 0;
-	static int (*realrecvmsg)(RECVMSG_SIG) = 0;
-	static int (*realrecvfrom)(RECVFROM_SIG) = 0;
+	extern int (*realbind)(BIND_SIG);
+	extern int (*realsendmsg)(SENDMSG_SIG);
+	extern ssize_t (*realsendto)(SENDTO_SIG);
+	extern int (*realrecvmsg)(RECVMSG_SIG);
+	extern int (*realrecvfrom)(RECVFROM_SIG);
 #endif
-	static int (*realconnect)(CONNECT_SIG) = 0;
-	static int (*realaccept)(ACCEPT_SIG) = 0;
-	static int (*reallisten)(LISTEN_SIG) = 0;
-	static int (*realsocket)(SOCKET_SIG) = 0;
-	static int (*realsetsockopt)(SETSOCKOPT_SIG) = 0;
-	static int (*realgetsockopt)(GETSOCKOPT_SIG) = 0;
-	static int (*realclose)(CLOSE_SIG) = 0;
-	static int (*realgetsockname)(GETSOCKNAME_SIG) = 0;
+	extern int (*realconnect)(CONNECT_SIG);
+	extern int (*realaccept)(ACCEPT_SIG);
+	extern int (*reallisten)(LISTEN_SIG);
+	extern int (*realsocket)(SOCKET_SIG);
+	extern int (*realsetsockopt)(SETSOCKOPT_SIG);
+	extern int (*realgetsockopt)(GETSOCKOPT_SIG);
+	extern int (*realclose)(CLOSE_SIG);
+	extern int (*realgetsockname)(GETSOCKNAME_SIG);
 
 ssize_t zt_sendto(SENDTO_SIG);
 ssize_t zt_sendmsg(SENDMSG_SIG);

src/SDK_Intercept.c

@@ -63,6 +63,30 @@ void dwr(int level, const char *fmt, ... );
 pthread_key_t thr_id_key;
 char *api_netpath;
 
+// externs common between SDK_Intercept and SDK_Socket from SDK.h
+#if defined(__linux__)
+    int (*realaccept4)(ACCEPT4_SIG) = 0;
+    #if !defined(__ANDROID__)
+        int (*realsyscall)(SYSCALL_SIG) = 0;
+    #endif
+#endif
+
+#if !defined(__ANDROID__)
+     int (*realbind)(BIND_SIG) = 0;
+     int (*realsendmsg)(SENDMSG_SIG) = 0;
+     ssize_t (*realsendto)(SENDTO_SIG) = 0;
+     int (*realrecvmsg)(RECVMSG_SIG) = 0;
+     int (*realrecvfrom)(RECVFROM_SIG) = 0;
+#endif
+     int (*realconnect)(CONNECT_SIG) = 0;
+     int (*realaccept)(ACCEPT_SIG) = 0;
+     int (*reallisten)(LISTEN_SIG) = 0;
+     int (*realsocket)(SOCKET_SIG) = 0;
+     int (*realsetsockopt)(SETSOCKOPT_SIG) = 0;
+     int (*realgetsockopt)(GETSOCKOPT_SIG) = 0;
+     int (*realclose)(CLOSE_SIG);
+     int (*realgetsockname)(GETSOCKNAME_SIG) = 0;
+
     // ------------------------------------------------------------------------------
     // --------------------- Get Original socket API pointers -----------------------
     // ------------------------------------------------------------------------------
@@ -503,8 +527,10 @@ char *api_netpath;
 
     int close(CLOSE_SIG) {
         dwr(MSG_DEBUG, " close(%d)\n", fd);
-        check_intercept_enabled_for_thread();
-        return realclose(fd);
+        if(!check_intercept_enabled_for_thread()) { 
+            return realclose(fd);
+        }
+        zt_close(fd);
     }
 
     // ------------------------------------------------------------------------------

src/SDK_RPC.c

@@ -47,6 +47,10 @@
 #include "SDK.h"
 #include "SDK_RPC.h"
 
+// externs common between SDK_Intercept and SDK_Socket from SDK.h
+int (*realsocket)(SOCKET_SIG);
+int (*realconnect)(CONNECT_SIG);
+
 #ifdef __cplusplus
 extern "C" {
 #endif

src/SDK_Sockets.c

@@ -74,16 +74,21 @@
     
 void print_addr(struct sockaddr *addr);
 void dwr(int level, const char *fmt, ... );
-
 char *api_netpath = (char *)0;
-    
+
     // ------------------------------------------------------------------------------
     // ---------------------------------- zt_init_rpc -------------------------------
     // ------------------------------------------------------------------------------
     
+    // Assembles (and/or) sets the RPC path for communication with the ZeroTier service
     void zt_init_rpc(char *path, char *nwid)
     {
         dwr(MSG_DEBUG, "zt_init_rpc\n");
+        // Just double check we have 
+        if(!realconnect) {
+            load_symbols();
+        }
+
         if(!api_netpath) {
             #if defined(SDK_BUNDLED)
                 // Get the path/nwid from the user application
@@ -373,9 +378,9 @@ char *api_netpath = (char *)0;
         struct connect_st rpc_st;
 #if defined(__linux__)
     #if !defined(__ANDROID__)
-        rpc_st.__tid = syscall(SYS_gettid);
+        //rpc_st.__tid = syscall(SYS_gettid);
     #else
-        rpc_st.__tid = gettid(); // dummy value
+        //rpc_st.__tid = gettid(); // dummy value
     #endif
 #endif
         rpc_st.__fd = __fd;
@@ -482,8 +487,9 @@ char *api_netpath = (char *)0;
     // int fd
 
     int zt_close(CLOSE_SIG) {
-        dwr(MSG_DEBUG, "zt_close(%d)", fd);
-        return close(fd);
+        get_api_netpath();
+        dwr(MSG_DEBUG, "zt_close(%d)\n", fd);
+        return realclose(fd);
     }
     
     // ------------------------------------------------------------------------------

tests/udp_client.c

@@ -10,6 +10,11 @@
 
 int main(int argc, char * argv[])
 {
+    if(argc < 2) {
+        printf("usage: udp_client <port>\n");
+        return 0;
+    }
+
     int port = atoi(argv[1]);
 
     printf("cpp_udp_socket_client_test():\n");