- unbound tries to set the ulimit fds when started as server.

if that does not work, it will scale back its requirements.


git-svn-id: file:///svn/unbound/trunk@1022 be551aaa-1e26-0410-a405-d3ace91eadb9

daemon/unbound.c

@@ -91,17 +91,22 @@ checkrlimits(struct config_file* cfg)
 			(int)cfg->incoming_num_tcp:0));
 	size_t ifs = (size_t)(cfg->num_ifs==0?1:cfg->num_ifs);
 	size_t listen_num = list*ifs;
-	size_t out_ifs = (size_t)(cfg->num_out_ifs==0?1:cfg->num_out_ifs);
-	size_t outnum = cfg->outgoing_num_ports*out_ifs + cfg->outgoing_num_tcp;
+	size_t out_ifs = (size_t)(cfg->num_out_ifs==0?
+		( (cfg->do_ip4?1:0) + (cfg->do_ip6?1:0) ) :cfg->num_out_ifs);
+	size_t outudpnum = cfg->outgoing_num_ports*out_ifs;
+	size_t outtcpnum = cfg->outgoing_num_tcp;
 	size_t misc = 4; /* logfile, pidfile, stdout... */
-	size_t perthread = listen_num + outnum + 2/*cmdpipe*/ + 2/*libevent*/
-		+ misc; 
+	size_t perthread_noudp = listen_num + outtcpnum + 
+		2/*cmdpipe*/ + 2/*libevent*/ + misc; 
+	size_t perthread = perthread_noudp + outudpnum;
+
 #if !defined(HAVE_PTHREAD) && !defined(HAVE_SOLARIS_THREADS)
 	int numthread = 1; /* it forks */
 #else
 	int numthread = cfg->num_threads;
 #endif
 	size_t total = numthread * perthread + misc;
+	size_t avail;
 	struct rlimit rlim;
 	if(getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
 		log_warn("getrlimit: %s", strerror(errno));
@@ -110,13 +115,24 @@ checkrlimits(struct config_file* cfg)
 	if(rlim.rlim_cur == (rlim_t)RLIM_INFINITY)
 		return;
 	if((size_t)rlim.rlim_cur < total) {
-		log_err("Not enough sockets available. Increase "
-			"ulimit(open files).");
-		log_err("or decrease number of threads, outgoing num ports, "
-			"outgoing num tcp or number of interfaces");
-		log_err("estimate %u fds high mark, %u available", 
-			(unsigned)total, (unsigned)rlim.rlim_cur);
-		fatal_exit("Not enough file descriptors available");
+		avail = (size_t)rlim.rlim_cur;
+		rlim.rlim_cur = (rlim_t)(total + 10);
+		rlim.rlim_max = (rlim_t)(total + 10);
+		if(setrlimit(RLIMIT_NOFILE, &rlim) < 0) {
+			log_warn("setrlimit: %s", strerror(errno));
+			log_warn("cannot increase max open fds from %u to %u",
+				(unsigned)avail, (unsigned)total+10);
+			cfg->outgoing_num_ports = (int)((avail 
+				- numthread*perthread_noudp 
+				- 10 /* safety margin */)
+				/(numthread*out_ifs));
+			log_warn("continuing with less udp ports: %u",
+				cfg->outgoing_num_ports);
+			log_warn("increase ulimit or decrease threads, ports in config to remove this warning");
+			return;
+		}
+		log_warn("increased limit(open files) from %u to %u",
+			(unsigned)avail, (unsigned)total+10);
 	}
 }
 

doc/Changelog

@@ -1,3 +1,7 @@
+8 April 2008: Wouter
+	- unbound tries to set the ulimit fds when started as server.
+	  if that does not work, it will scale back its requirements.
+
 27 March 2008: Wouter
 	- documented /dev/random symlink from chrootdir as FAQ entry.
 

doc/example.conf

@@ -54,7 +54,7 @@ server:
 	# port range. A larger port range gives more resistance to certain
 	# spoof attacks, as it gets harder to guess which port is used. 
 	# But also takes more system resources (for open sockets).
-	# outgoing-range: 16
+	# outgoing-range: 256
 
 	# number of outgoing simultaneous tcp buffers to hold per thread.
 	# outgoing-num-tcp: 10

doc/unbound.conf.5

@@ -124,7 +124,7 @@ Default is 1053.
 .TP
 .B outgoing\-range: \fI<number>
 Number of ports to open. This number is opened per thread for every outgoing
-query interface. Must be at least 1. Default is 16.
+query interface. Must be at least 1. Default is 256.
 Larger numbers give more protection against spoofing attempts, but need
 extra resources from the operating system.
 .TP

services/listen_dnsport.c

@@ -86,7 +86,7 @@ verbose_print_addr(struct addrinfo *addr)
 }
 
 int
-create_udp_sock(struct addrinfo *addr, int v6only)
+create_udp_sock(struct addrinfo *addr, int v6only, int* inuse)
 {
 	int s;
 # if defined(IPV6_USE_MIN_MTU)
@@ -97,6 +97,7 @@ create_udp_sock(struct addrinfo *addr, int v6only)
 	verbose_print_addr(addr);
 	if((s = socket(addr->ai_family, addr->ai_socktype, 0)) == -1) {
 		log_err("can't create socket: %s", strerror(errno));
+		*inuse = 0;
 		return -1;
 	}
 	if(addr->ai_family == AF_INET6) {
@@ -107,6 +108,7 @@ create_udp_sock(struct addrinfo *addr, int v6only)
 				&val, (socklen_t)sizeof(val)) < 0) {
 				log_err("setsockopt(..., IPV6_V6ONLY"
 					", ...) failed: %s", strerror(errno));
+				*inuse = 0;
 				return -1;
 			}
 		}
@@ -124,16 +126,23 @@ create_udp_sock(struct addrinfo *addr, int v6only)
 			&on, (socklen_t)sizeof(on)) < 0) {
 			log_err("setsockopt(..., IPV6_USE_MIN_MTU, "
 				"...) failed: %s", strerror(errno));
+			*inuse = 0;
 			return -1;
 		}
 # endif
 	}
 	if(bind(s, (struct sockaddr*)addr->ai_addr, addr->ai_addrlen) != 0) {
-		log_err("can't bind socket: %s", strerror(errno));
+#ifdef EADDRINUSE
+		*inuse = (errno == EADDRINUSE);
+		if(errno != EADDRINUSE)
+#endif
+			log_err("can't bind socket: %s", strerror(errno));
 		return -1;
 	}
-	if(!fd_set_nonblock(s))
+	if(!fd_set_nonblock(s)) {
+		*inuse = 0;
 		return -1;
+	}
 	return s;
 }
 
@@ -203,7 +212,7 @@ make_sock(int stype, const char* ifname, const char* port,
 	struct addrinfo *hints, int v6only)
 {
 	struct addrinfo *res = NULL;
-	int r, s;
+	int r, s, inuse;
 	hints->ai_socktype = stype;
 	if((r=getaddrinfo(ifname, port, hints, &res)) != 0 || !res) {
 		log_err("node %s:%s getaddrinfo: %s %s", 
@@ -211,9 +220,12 @@ make_sock(int stype, const char* ifname, const char* port,
 			r==EAI_SYSTEM?(char*)strerror(errno):"");
 		return -1;
 	}
-	if(stype == SOCK_DGRAM)
-		s = create_udp_sock(res, v6only);
-	else	s = create_tcp_accept_sock(res, v6only);
+	if(stype == SOCK_DGRAM) {
+		s = create_udp_sock(res, v6only, &inuse);
+		if(s == -1 && inuse) {
+			log_err("bind: address already in use");
+		}
+	}	else	s = create_tcp_accept_sock(res, v6only);
 	freeaddrinfo(res);
 	return s;
 }

services/listen_dnsport.h

@@ -168,8 +168,9 @@ size_t listen_get_mem(struct listen_dnsport* listen);
  * @param addr: address info ready to make socket.
  * @param v6only: if enabled, IP6 sockets get IP6ONLY option set.
  * 	if enabled with value 2 IP6ONLY option is disabled.
+ * @param inuse: on error, this is set true if the port was in use.
  * @return: the socket. -1 on error.
  */
-int create_udp_sock(struct addrinfo* addr, int v6only);
+int create_udp_sock(struct addrinfo* addr, int v6only, int* inuse);
 
 #endif /* LISTEN_DNSPORT_H */

services/outside_network.c

@@ -284,10 +284,12 @@ outnet_udp_cb(struct comm_point* c, void* arg, int error,
   * @param ifname: on which interface to open the port.
   * @param hints: hints on family and passiveness preset.
   * @param porthint: if not -1, it gives the port to base range on.
+  * @param inuse: on error, true if the port was in use.
   * @return: file descriptor
   */
 static int 
-open_udp_port_range(const char* ifname, struct addrinfo* hints, int porthint)
+open_udp_port_range(const char* ifname, struct addrinfo* hints, int porthint,
+	int* inuse)
 {
 	struct addrinfo *res = NULL;
 	int r, s;
@@ -308,7 +310,7 @@ open_udp_port_range(const char* ifname, struct addrinfo* hints, int porthint)
 			r==EAI_SYSTEM?(char*)strerror(errno):"");
 		return -1;
 	}
-	s = create_udp_sock(res, 1);
+	s = create_udp_sock(res, 1, inuse);
 	freeaddrinfo(res);
 	return s;
 }
@@ -346,11 +348,23 @@ make_udp_range(struct comm_point** coms, const char* ifname,
 		hints.ai_family = AF_INET6;
 	hints.ai_socktype = SOCK_DGRAM;
 	for(i=0; i<num_ports; i++) {
-		int fd = open_udp_port_range(ifname, &hints, porthint);
-		if(porthint != -1) 
-			porthint++;
-		if(fd == -1)
-			continue;
+		int fd = -1;
+		int inuse = 1;
+		while(fd == -1 && inuse) {
+			inuse = 0;
+			fd = open_udp_port_range(ifname, &hints, 
+				porthint, &inuse);
+			if(fd == -1 && porthint != -1 && inuse)
+				verbose(VERB_DETAIL, "%sport %d already in use, skipped", 
+					(do_ip6?"IP6 ":""), porthint);
+			if(porthint != -1) {
+				porthint++;
+				if(porthint > 65535) {
+					log_err("ports maxed. cannot open ports");
+					return done;
+				}
+			}
+		}
 		coms[done] = comm_point_create_udp(outnet->base, fd, 
 			outnet->udp_buff, outnet_udp_cb, outnet);
 		if(coms[done])

util/config_file.c

@@ -79,7 +79,7 @@ config_create()
 	cfg->do_tcp = 1;
 	cfg->use_syslog = 1;
 	cfg->outgoing_base_port = cfg->port + 2000;
-	cfg->outgoing_num_ports = 16;
+	cfg->outgoing_num_ports = 256;
 	cfg->outgoing_num_tcp = 10;
 	cfg->incoming_num_tcp = 10;
 	cfg->msg_buffer_size = 65552; /* 64 k + a small margin */
@@ -150,6 +150,8 @@ struct config_file* config_create_forlib()
 	free(cfg->chrootdir);
 	cfg->chrootdir = NULL;
 	cfg->verbosity = 0;
+	cfg->outgoing_num_ports = 16; /* in library use, this is 'reasonable'
+		and probably within the ulimit(maxfds) of the user */
 	cfg->outgoing_num_tcp = 2;
 	cfg->msg_cache_size = 1024*1024;
 	cfg->msg_cache_slabs = 1;