X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/8d9dc9f99db13d42272b7c150f2e6849331ccdc1..b11ed3b1504d526a4b571bc3d80f4e5f1628dc75:/socket.c

diff --git a/socket.c b/socket.c
index 910c2dc0..f8d46590 100644
--- a/socket.c
+++ b/socket.c
@@ -81,7 +81,7 @@ static int open_socket_in(int type, int port)
 		return -1;
 	}
   
-	bzero((char *)&sock,sizeof(sock));
+	memset((char *)&sock,0,sizeof(sock));
 	memcpy((char *)&sock.sin_addr,(char *)hp->h_addr, hp->h_length);
 	sock.sin_port = htons(port);
 	sock.sin_family = hp->h_addrtype;
@@ -120,8 +120,6 @@ void start_accept_loop(int port, int (*fn)(int ))
 {
 	int s;
 
-	signal(SIGCHLD, SIG_IGN);
-
 	/* open an incoming socket */
 	s = open_socket_in(SOCK_STREAM, port);
 	if (s == -1)
@@ -155,6 +153,15 @@ void start_accept_loop(int port, int (*fn)(int ))
 
 		if (fd == -1) continue;
 
+		signal(SIGCHLD, SIG_IGN);
+
+		/* we shouldn't have any children left hanging around
+		   but I have had reports that on Digital Unix zombies
+		   are produced, so this ensures that they are reaped */
+#ifdef WNOHANG
+		waitpid(-1, NULL, WNOHANG);
+#endif
+
 		if (fork()==0) {
 			close(s);
 
@@ -274,6 +281,8 @@ become a daemon, discarding the controlling terminal
 ****************************************************************************/
 void become_daemon(void)
 {
+	int i;
+
 	if (fork())
 		_exit(0);
 
@@ -292,9 +301,12 @@ void become_daemon(void)
 	}
 #endif /* TIOCNOTTY */
 #endif
-	close(0);
-	close(1);
-	close(2);
+	/* make sure that stdin, stdout an stderr don't stuff things
+           up (library functions, for example) */
+	for (i=0;i<3;i++) {
+		close(i); 
+		open("/dev/null", O_RDWR);
+	}
 }
 
 /*******************************************************************
@@ -327,8 +339,10 @@ char *client_name(int fd)
 	int     length = sizeof(sa);
 	static char name_buf[100];
 	struct hostent *hp;
+	char **p;
+	char *def = "UNKNOWN";
 
-	strcpy(name_buf,"UNKNOWN");
+	strcpy(name_buf,def);
 
 	if (getpeername(fd, &sa, &length)) {
 		exit_cleanup(1);
@@ -341,5 +355,23 @@ char *client_name(int fd)
 		strlcpy(name_buf,(char *)hp->h_name,sizeof(name_buf) - 1);
 	}
 
+
+	/* do a forward lookup as well to prevent spoofing */
+	hp = gethostbyname(name_buf);
+	if (!hp) {
+		strcpy(name_buf,def);
+		rprintf(FERROR,"reverse name lookup failed\n");
+	} else {
+		for (p=hp->h_addr_list;*p;p++) {
+			if (memcmp(*p, &sockin->sin_addr, hp->h_length) == 0) {
+				break;
+			}
+		}
+		if (!*p) {
+			strcpy(name_buf,def);
+			rprintf(FERROR,"reverse name lookup mismatch - spoofed address?\n");
+		} 
+	}
+
 	return name_buf;
 }