X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Ftincctl.c;h=dd0bbcc220677d97bfbc1f83cacb677e54d18ed9;hp=b977d13765cc9d33a632118c2feae55c2207f9a3;hb=a717b9bcfbe811787fd6718fb3f8fb3f272bcfb9;hpb=68de7b481e54d6a7c573d9a2d61f76d4d3a6b2f9

diff --git a/src/tincctl.c b/src/tincctl.c
index b977d137..dd0bbcc2 100644
--- a/src/tincctl.c
+++ b/src/tincctl.c
@@ -21,6 +21,11 @@
 
 #include <getopt.h>
 
+#ifdef HAVE_READLINE
+#include "readline/readline.h"
+#include "readline/history.h"
+#endif
+
 #include "xalloc.h"
 #include "protocol.h"
 #include "control_common.h"
@@ -31,9 +36,17 @@
 #include "tincctl.h"
 #include "top.h"
 
+#ifdef HAVE_MINGW
+#define mkdir(a, b) mkdir(a)
+#endif
+
+
 /* The name this program was run with. */
 static char *program_name = NULL;
 
+static char **orig_argv;
+static int orig_argc;
+
 /* If nonzero, display usage information and exit. */
 static bool show_help = false;
 
@@ -41,13 +54,15 @@ static bool show_help = false;
 static bool show_version = false;
 
 static char *name = NULL;
-static char *identname = NULL;				/* program name for syslog */
-static char *pidfilename = NULL;			/* pid file location */
-static char controlcookie[1024];
+static char *identname = NULL;          /* program name for syslog */
+static char *pidfilename = NULL;        /* pid file location */
+static char *confdir = NULL;
+static char controlcookie[1025];
 char *netname = NULL;
 char *confbase = NULL;
 static char *tinc_conf = NULL;
 static char *hosts_dir = NULL;
+struct timeval now;
 
 // Horrible global variables...
 static int pid = 0;
@@ -57,6 +72,7 @@ static int code;
 static int req;
 static int result;
 static bool force = false;
+static bool tty = true;
 
 #ifdef HAVE_MINGW
 static struct WSAData wsa_state;
@@ -106,6 +122,7 @@ static void usage(bool status) {
 				"Valid commands are:\n"
 				"  init [name]                Create initial configuration files.\n"
 				"  config                     Change configuration:\n"
+				"    [get] VARIABLE           - print current value of VARIABLE\n"
 				"    [set] VARIABLE VALUE     - set VARIABLE to VALUE\n"
 				"    add VARIABLE VALUE       - add VARIABLE with the given VALUE\n"
 				"    del VARIABLE [VALUE]     - remove VARIABLE [only ones with watching VALUE]\n"
@@ -118,11 +135,11 @@ static void usage(bool status) {
 				"  generate-rsa-keys [bits]   Generate a new RSA public/private keypair.\n"
 				"  generate-ecdsa-keys        Generate a new ECDSA public/private keypair.\n"
 				"  dump                       Dump a list of one of the following things:\n"
-				"    nodes                    - all known nodes in the VPN\n"
+				"    [reachable] nodes        - all known nodes in the VPN\n"
 				"    edges                    - all known connections in the VPN\n"
 				"    subnets                  - all known subnets in the VPN\n"
 				"    connections              - all meta connections with ourself\n"
-				"    graph                    - graph of the VPN in dotty format\n"
+				"    [di]graph                - graph of the VPN in dotty format\n"
 				"  info NODE|SUBNET|ADDRESS   Give information about a particular NODE, SUBNET or ADDRESS.\n"
 				"  purge                      Purge unreachable nodes\n"
 				"  debug N                    Set debug level\n"
@@ -147,34 +164,34 @@ static bool parse_options(int argc, char **argv) {
 
 	while((r = getopt_long(argc, argv, "c:n:Dd::Lo:RU:", long_options, &option_index)) != EOF) {
 		switch (r) {
-			case 0:				/* long option */
+			case 0:   /* long option */
 				break;
 
-			case 'c':				/* config file */
+			case 'c': /* config file */
 				confbase = xstrdup(optarg);
 				break;
 
-			case 'n':				/* net name given */
+			case 'n': /* net name given */
 				netname = xstrdup(optarg);
 				break;
 
-			case 1:					/* show help */
+			case 1:   /* show help */
 				show_help = true;
 				break;
 
-			case 2:					/* show version */
+			case 2:   /* show version */
 				show_version = true;
 				break;
 
-			case 5:					/* open control socket here */
+			case 5:   /* open control socket here */
 				pidfilename = xstrdup(optarg);
 				break;
 
-			case 6:
+			case 6:   /* force */
 				force = true;
 				break;
 
-			case '?':
+			case '?': /* wrong options */
 				usage(true);
 				return false;
 
@@ -183,23 +200,109 @@ static bool parse_options(int argc, char **argv) {
 		}
 	}
 
-	if(!netname) {
-		netname = getenv("NETNAME");
-		if(netname)
-			netname = xstrdup(netname);
+	if(!netname && (netname = getenv("NETNAME")))
+		netname = xstrdup(netname);
+
+	/* netname "." is special: a "top-level name" */
+
+	if(netname && (!*netname || !strcmp(netname, "."))) {
+		free(netname);
+		netname = NULL;
+	}
+
+	if(netname && (strpbrk(netname, "\\/") || *netname == '.')) {
+		fprintf(stderr, "Invalid character in netname!\n");
+		return false;
 	}
 
 	return true;
 }
 
-static FILE *ask_and_open(const char *filename, const char *what, const char *mode) {
+static void disable_old_keys(const char *filename, const char *what) {
+	char tmpfile[PATH_MAX] = "";
+	char buf[1024];
+	bool disabled = false;
+	bool block = false;
+	bool error = false;
+	FILE *r, *w;
+
+	r = fopen(filename, "r");
+	if(!r)
+		return;
+
+	snprintf(tmpfile, sizeof tmpfile, "%s.tmp", filename);
+
+	w = fopen(tmpfile, "w");
+
+	while(fgets(buf, sizeof buf, r)) {
+		if(!block && !strncmp(buf, "-----BEGIN ", 11)) {
+			if((strstr(buf, " EC ") && strstr(what, "ECDSA")) || (strstr(buf, " RSA ") && strstr(what, "RSA"))) {
+				disabled = true;
+				block = true;
+			}
+		}
+
+		bool ecdsapubkey = !strncasecmp(buf, "ECDSAPublicKey", 14) && strchr(" \t=", buf[14]) && strstr(what, "ECDSA");
+
+		if(ecdsapubkey)
+			disabled = true;
+
+		if(w) {
+			if(block || ecdsapubkey)
+				fputc('#', w);
+			if(fputs(buf, w) < 0) {
+				error = true;
+				break;
+			}
+		}
+
+		if(block && !strncmp(buf, "-----END ", 9))
+			block = false;
+	}
+
+	if(w)
+		if(fclose(w) < 0)
+			error = true;
+	if(ferror(r) || fclose(r) < 0)
+		error = true;
+
+	if(disabled) {
+		if(!w || error) {
+			fprintf(stderr, "Warning: old key(s) found, remove them by hand!\n");
+			if(w)
+				unlink(tmpfile);
+			return;
+		}
+
+#ifdef HAVE_MINGW
+		// We cannot atomically replace files on Windows.
+		char bakfile[PATH_MAX] = "";
+		snprintf(bakfile, sizeof bakfile, "%s.bak", filename);
+		if(rename(filename, bakfile) || rename(tmpfile, filename)) {
+			rename(bakfile, filename);
+#else
+		if(rename(tmpfile, filename)) {
+#endif
+			fprintf(stderr, "Warning: old key(s) found, remove them by hand!\n");
+		} else  {
+#ifdef HAVE_MINGW
+			unlink(bakfile);
+#endif
+			fprintf(stderr, "Warning: old key(s) found and disabled.\n");
+		}
+	}
+
+	unlink(tmpfile);
+}
+
+static FILE *ask_and_open(const char *filename, const char *what, const char *mode, bool ask) {
 	FILE *r;
 	char *directory;
 	char buf[PATH_MAX];
 	char buf2[PATH_MAX];
 
 	/* Check stdin and stdout */
-	if(isatty(0) && isatty(1)) {
+	if(ask && tty) {
 		/* Ask for a file and/or directory name. */
 		fprintf(stdout, "Please enter a file to save %s to [%s]: ",
 				what, filename);
@@ -226,11 +329,13 @@ static FILE *ask_and_open(const char *filename, const char *what, const char *mo
 #endif
 		/* The directory is a relative path or a filename. */
 		directory = get_current_dir_name();
-		snprintf(buf2, sizeof buf2, "%s/%s", directory, filename);
+		snprintf(buf2, sizeof buf2, "%s" SLASH "%s", directory, filename);
 		filename = buf2;
 	}
 
-	umask(0077);				/* Disallow everything for group and other */
+	umask(0077); /* Disallow everything for group and other */
+
+	disable_old_keys(filename, what);
 
 	/* Open it first to keep the inode busy */
 
@@ -248,10 +353,10 @@ static FILE *ask_and_open(const char *filename, const char *what, const char *mo
   Generate a public/private ECDSA keypair, and ask for a file to store
   them in.
 */
-static bool ecdsa_keygen() {
+static bool ecdsa_keygen(bool ask) {
 	ecdsa_t key;
 	FILE *f;
-	char *filename;
+	char *pubname, *privname;
 
 	fprintf(stderr, "Generating ECDSA keypair:\n");
 
@@ -261,44 +366,38 @@ static bool ecdsa_keygen() {
 	} else
 		fprintf(stderr, "Done.\n");
 
-	xasprintf(&filename, "%s/ecdsa_key.priv", confbase);
-	f = ask_and_open(filename, "private ECDSA key", "a");
+	xasprintf(&privname, "%s" SLASH "ecdsa_key.priv", confbase);
+	f = ask_and_open(privname, "private ECDSA key", "a", ask);
+	free(privname);
 
 	if(!f)
 		return false;
-  
+
 #ifdef HAVE_FCHMOD
 	/* Make it unreadable for others. */
 	fchmod(fileno(f), 0600);
 #endif
-		
-	if(ftell(f))
-		fprintf(stderr, "Appending key to existing contents.\nMake sure only one key is stored in the file.\n");
 
 	ecdsa_write_pem_private_key(&key, f);
 
 	fclose(f);
-	free(filename);
 
 	if(name)
-		xasprintf(&filename, "%s/hosts/%s", confbase, name);
+		xasprintf(&pubname, "%s" SLASH "hosts" SLASH "%s", confbase, name);
 	else
-		xasprintf(&filename, "%s/ecdsa_key.pub", confbase);
+		xasprintf(&pubname, "%s" SLASH "ecdsa_key.pub", confbase);
 
-	f = ask_and_open(filename, "public ECDSA key", "a");
+	f = ask_and_open(pubname, "public ECDSA key", "a", ask);
+	free(pubname);
 
 	if(!f)
 		return false;
 
-	if(ftell(f))
-		fprintf(stderr, "Appending key to existing contents.\nMake sure only one key is stored in the file.\n");
-
 	char *pubkey = ecdsa_get_base64_public_key(&key);
 	fprintf(f, "ECDSAPublicKey = %s\n", pubkey);
 	free(pubkey);
 
 	fclose(f);
-	free(filename);
 
 	return true;
 }
@@ -307,10 +406,10 @@ static bool ecdsa_keygen() {
   Generate a public/private RSA keypair, and ask for a file to store
   them in.
 */
-static bool rsa_keygen(int bits) {
+static bool rsa_keygen(int bits, bool ask) {
 	rsa_t key;
 	FILE *f;
-	char *filename;
+	char *pubname, *privname;
 
 	fprintf(stderr, "Generating %d bits keys:\n", bits);
 
@@ -320,42 +419,36 @@ static bool rsa_keygen(int bits) {
 	} else
 		fprintf(stderr, "Done.\n");
 
-	xasprintf(&filename, "%s/rsa_key.priv", confbase);
-	f = ask_and_open(filename, "private RSA key", "a");
+	xasprintf(&privname, "%s" SLASH "rsa_key.priv", confbase);
+	f = ask_and_open(privname, "private RSA key", "a", ask);
+	free(privname);
 
 	if(!f)
 		return false;
-  
+
 #ifdef HAVE_FCHMOD
 	/* Make it unreadable for others. */
 	fchmod(fileno(f), 0600);
 #endif
-		
-	if(ftell(f))
-		fprintf(stderr, "Appending key to existing contents.\nMake sure only one key is stored in the file.\n");
 
 	rsa_write_pem_private_key(&key, f);
 
 	fclose(f);
-	free(filename);
 
 	if(name)
-		xasprintf(&filename, "%s/hosts/%s", confbase, name);
+		xasprintf(&pubname, "%s" SLASH "hosts" SLASH "%s", confbase, name);
 	else
-		xasprintf(&filename, "%s/rsa_key.pub", confbase);
+		xasprintf(&pubname, "%s" SLASH "rsa_key.pub", confbase);
 
-	f = ask_and_open(filename, "public RSA key", "a");
+	f = ask_and_open(pubname, "public RSA key", "a", ask);
+	free(pubname);
 
 	if(!f)
 		return false;
 
-	if(ftell(f))
-		fprintf(stderr, "Appending key to existing contents.\nMake sure only one key is stored in the file.\n");
-
 	rsa_write_pem_public_key(&key, f);
 
 	fclose(f);
-	free(filename);
 
 	return true;
 }
@@ -380,38 +473,40 @@ static void make_names(void) {
 		if(!RegQueryValueEx(key, NULL, 0, 0, installdir, &len)) {
 			if(!confbase) {
 				if(netname)
-					xasprintf(&confbase, "%s/%s", installdir, netname);
+					xasprintf(&confbase, "%s" SLASH "%s", installdir, netname);
 				else
 					xasprintf(&confbase, "%s", installdir);
 			}
 		}
 		if(!pidfilename)
-			xasprintf(&pidfilename, "%s/pid", confbase);
+			xasprintf(&pidfilename, "%s" SLASH "pid", confbase);
 		RegCloseKey(key);
 	}
 
 	if(!*installdir) {
 #endif
+	confdir = xstrdup(CONFDIR);
 
 	if(!pidfilename)
-		xasprintf(&pidfilename, "%s/run/%s.pid", LOCALSTATEDIR, identname);
+		xasprintf(&pidfilename, "%s" SLASH "run" SLASH "%s.pid", LOCALSTATEDIR, identname);
 
 	if(netname) {
 		if(!confbase)
-			xasprintf(&confbase, CONFDIR "/tinc/%s", netname);
+			xasprintf(&confbase, CONFDIR SLASH "tinc" SLASH "%s", netname);
 		else
 			fprintf(stderr, "Both netname and configuration directory given, using the latter...\n");
 	} else {
 		if(!confbase)
-			xasprintf(&confbase, CONFDIR "/tinc");
+			xasprintf(&confbase, CONFDIR SLASH "tinc");
 	}
 
 #ifdef HAVE_MINGW
-	}
+	} else
+		confdir = xstrdup(installdir);
 #endif
 
-	xasprintf(&tinc_conf, "%s/tinc.conf", confbase);
-	xasprintf(&hosts_dir, "%s/hosts", confbase);
+	xasprintf(&tinc_conf, "%s" SLASH "tinc.conf", confbase);
+	xasprintf(&hosts_dir, "%s" SLASH "hosts", confbase);
 }
 
 static char buffer[4096];
@@ -485,7 +580,7 @@ bool sendline(int fd, char *format, ...) {
 		blen -= result;
 	}
 
-	return true;	
+	return true;
 }
 
 static void pcap(int fd, FILE *out, int snaplen) {
@@ -592,27 +687,44 @@ static bool remove_service(void) {
 }
 #endif
 
-static bool connect_tincd() {
-	if(fd >= 0)
-		return true;
+static bool connect_tincd(bool verbose) {
+	if(fd >= 0) {
+		fd_set r;
+		FD_ZERO(&r);
+		FD_SET(fd, &r);
+		struct timeval tv = {0, 0};
+		if(select(fd + 1, &r, NULL, NULL, &tv)) {
+			fprintf(stderr, "Previous connection to tincd lost, reconnecting.\n");
+			close(fd);
+			fd = -1;
+		} else {
+			return true;
+		}
+	}
 
 	FILE *f = fopen(pidfilename, "r");
 	if(!f) {
-		fprintf(stderr, "Could not open pid file %s: %s\n", pidfilename, strerror(errno));
+		if(verbose)
+			fprintf(stderr, "Could not open pid file %s: %s\n", pidfilename, strerror(errno));
 		return false;
 	}
 
-	char host[128];
-	char port[128];
+	char host[129];
+	char port[129];
 
 	if(fscanf(f, "%20d %1024s %128s port %128s", &pid, controlcookie, host, port) != 4) {
-		fprintf(stderr, "Could not parse pid file %s\n", pidfilename);
+		if(verbose)
+			fprintf(stderr, "Could not parse pid file %s\n", pidfilename);
+		fclose(f);
 		return false;
 	}
 
+	fclose(f);
+
 #ifdef HAVE_MINGW
 	if(WSAStartup(MAKEWORD(2, 2), &wsa_state)) {
-		fprintf(stderr, "System call `%s' failed: %s", "WSAStartup", winerror(GetLastError()));
+		if(verbose)
+			fprintf(stderr, "System call `%s' failed: %s", "WSAStartup", winerror(GetLastError()));
 		return false;
 	}
 #endif
@@ -627,13 +739,15 @@ static bool connect_tincd() {
 	struct addrinfo *res = NULL;
 
 	if(getaddrinfo(host, port, &hints, &res) || !res) {
-		fprintf(stderr, "Cannot resolve %s port %s: %s", host, port, strerror(errno));
+		if(verbose)
+			fprintf(stderr, "Cannot resolve %s port %s: %s", host, port, strerror(errno));
 		return false;
 	}
 
 	fd = socket(res->ai_family, SOCK_STREAM, IPPROTO_TCP);
 	if(fd < 0) {
-		fprintf(stderr, "Cannot create TCP socket: %s\n", sockstrerror(sockerrno));
+		if(verbose)
+			fprintf(stderr, "Cannot create TCP socket: %s\n", sockstrerror(sockerrno));
 		return false;
 	}
 
@@ -641,12 +755,16 @@ static bool connect_tincd() {
 	unsigned long arg = 0;
 
 	if(ioctlsocket(fd, FIONBIO, &arg) != 0) {
-		fprintf(stderr, "ioctlsocket failed: %s", sockstrerror(sockerrno));
+		if(verbose)
+			fprintf(stderr, "ioctlsocket failed: %s", sockstrerror(sockerrno));
 	}
 #endif
 
 	if(connect(fd, res->ai_addr, res->ai_addrlen) < 0) {
-		fprintf(stderr, "Cannot connect to %s port %s: %s\n", host, port, sockstrerror(sockerrno));
+		if(verbose)
+			fprintf(stderr, "Cannot connect to %s port %s: %s\n", host, port, sockstrerror(sockerrno));
+		close(fd);
+		fd = -1;
 		return false;
 	}
 
@@ -656,14 +774,20 @@ static bool connect_tincd() {
 	int version;
 
 	if(!recvline(fd, line, sizeof line) || sscanf(line, "%d %s %d", &code, data, &version) != 3 || code != 0) {
-		fprintf(stderr, "Cannot read greeting from control socket: %s\n", sockstrerror(sockerrno));
+		if(verbose)
+			fprintf(stderr, "Cannot read greeting from control socket: %s\n", sockstrerror(sockerrno));
+		close(fd);
+		fd = -1;
 		return false;
 	}
 
 	sendline(fd, "%d ^%s %d", ID, controlcookie, TINC_CTL_VERSION_CURRENT);
-	
+
 	if(!recvline(fd, line, sizeof line) || sscanf(line, "%d %d %d", &code, &version, &pid) != 3 || code != 4 || version != TINC_CTL_VERSION_CURRENT) {
-		fprintf(stderr, "Could not fully establish control socket connection\n");
+		if(verbose)
+			fprintf(stderr, "Could not fully establish control socket connection\n");
+		close(fd);
+		fd = -1;
 		return false;
 	}
 
@@ -672,60 +796,109 @@ static bool connect_tincd() {
 
 
 static int cmd_start(int argc, char *argv[]) {
-	int i, j;
-	char *c;
+	if(connect_tincd(false)) {
+		if(netname)
+			fprintf(stderr, "A tincd is already running for net `%s' with pid %d.\n", netname, pid);
+		else
+			fprintf(stderr, "A tincd is already running with pid %d.\n", pid);
+		return 0;
+	}
 
-	argc += optind;
-	argv -= optind;
-	char *slash = strrchr(argv[0], '/');
+	char *c;
+	char *slash = strrchr(program_name, '/');
 
 #ifdef HAVE_MINGW
-	if ((c = strrchr(argv[0], '\\')) > slash)
+	if ((c = strrchr(program_name, '\\')) > slash)
 		slash = c;
 #endif
 
-	if (slash++) {
-		c = xmalloc((slash - argv[0]) + sizeof("tincd"));
-		sprintf(c, "%.*stincd", (int)(slash - argv[0]), argv[0]);
-	}
+	if (slash++)
+		xasprintf(&c, "%.*stincd", (int)(slash - program_name), program_name);
 	else
 		c = "tincd";
 
-	argv[0] = c;
+	int nargc = 0;
+	char **nargv = xmalloc_and_zero((optind + argc) * sizeof *nargv);
 
-	for(i = j = 1; argv[i]; ++i)
-		if (i != optind && strcmp(argv[i], "--") != 0)
-			argv[j++] = argv[i];
+	nargv[nargc++] = c;
+	for(int i = 1; i < optind; i++)
+		nargv[nargc++] = orig_argv[i];
+	for(int i = 1; i < argc; i++)
+		nargv[nargc++] = argv[i];
 
-	argv[j] = NULL;
-	execvp(c, argv);
-	fprintf(stderr, "Could not start %s: %s\n", c, strerror(errno));
+#ifdef HAVE_MINGW
+	execvp(c, nargv);
+	fprintf(stderr, "Error starting %s: %s\n", c, strerror(errno));
 	return 1;
+#else
+	pid_t pid = fork();
+	if(pid == -1) {
+		fprintf(stderr, "Could not fork: %s\n", strerror(errno));
+		free(nargv);
+		return 1;
+	}
+
+	if(!pid)
+		exit(execvp(c, nargv));
+
+	free(nargv);
+
+	int status = -1;
+	if(waitpid(pid, &status, 0) != pid || !WIFEXITED(status) || WEXITSTATUS(status)) {
+		fprintf(stderr, "Error starting %s\n", c);
+		return 1;
+	}
+
+	return 0;
+#endif
 }
 
 static int cmd_stop(int argc, char *argv[]) {
 #ifndef HAVE_MINGW
-	if(!connect_tincd())
+	if(!connect_tincd(true)) {
+		if(pid) {
+			if(kill(pid, SIGTERM)) {
+				fprintf(stderr, "Could not send TERM signal to process with PID %u: %s\n", pid, strerror(errno));
+				return 1;
+			}
+
+			fprintf(stderr, "Sent TERM signal to process with PID %u.\n", pid);
+			waitpid(pid, NULL, 0);
+			return 0;
+		}
+
 		return 1;
+	}
 
 	sendline(fd, "%d %d", CONTROL, REQ_STOP);
 	if(!recvline(fd, line, sizeof line) || sscanf(line, "%d %d %d", &code, &req, &result) != 3 || code != CONTROL || req != REQ_STOP || result) {
 		fprintf(stderr, "Could not stop tinc daemon.\n");
 		return 1;
 	}
+
+	// Wait for tincd to close the connection...
+	fd_set r;
+	FD_ZERO(&r);
+	FD_SET(fd, &r);
+	select(fd + 1, &r, NULL, NULL, NULL);
 #else
 	if(!remove_service())
 		return 1;
 #endif
+	close(fd);
+	pid = 0;
+	fd = -1;
+
 	return 0;
 }
 
 static int cmd_restart(int argc, char *argv[]) {
-	return cmd_stop(argc, argv) ?: cmd_start(argc, argv);
+	cmd_stop(argc, argv);
+	return cmd_start(argc, argv);
 }
 
 static int cmd_reload(int argc, char *argv[]) {
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	sendline(fd, "%d %d", CONTROL, REQ_RELOAD);
@@ -739,16 +912,29 @@ static int cmd_reload(int argc, char *argv[]) {
 }
 
 static int cmd_dump(int argc, char *argv[]) {
+	bool only_reachable = false;
+
+	if(argc > 2 && !strcasecmp(argv[1], "reachable")) {
+		if(strcasecmp(argv[2], "nodes")) {
+			fprintf(stderr, "`reachable' only supported for nodes.\n");
+			usage(true);
+			return 1;
+		}
+		only_reachable = true;
+		argv++;
+		argc--;
+	}
+
 	if(argc != 2) {
 		fprintf(stderr, "Invalid number of arguments.\n");
 		usage(true);
 		return 1;
 	}
 
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
-	bool do_graph = false;
+	int do_graph = 0;
 
 	if(!strcasecmp(argv[1], "nodes"))
 		sendline(fd, "%d %d", CONTROL, REQ_DUMP_NODES);
@@ -761,19 +947,25 @@ static int cmd_dump(int argc, char *argv[]) {
 	else if(!strcasecmp(argv[1], "graph")) {
 		sendline(fd, "%d %d", CONTROL, REQ_DUMP_NODES);
 		sendline(fd, "%d %d", CONTROL, REQ_DUMP_EDGES);
-		do_graph = true;
+		do_graph = 1;
+	} else if(!strcasecmp(argv[1], "digraph")) {
+		sendline(fd, "%d %d", CONTROL, REQ_DUMP_NODES);
+		sendline(fd, "%d %d", CONTROL, REQ_DUMP_EDGES);
+		do_graph = 2;
 	} else {
 		fprintf(stderr, "Unknown dump type '%s'.\n", argv[1]);
 		usage(true);
 		return 1;
 	}
 
-	if(do_graph)
+	if(do_graph == 1)
+		printf("graph {\n");
+	else if(do_graph == 2)
 		printf("digraph {\n");
 
 	while(recvline(fd, line, sizeof line)) {
 		char node1[4096], node2[4096];
-		int n = sscanf(line, "%d %d %s to %s", &code, &req, node1, node2);
+		int n = sscanf(line, "%d %d %s %s", &code, &req, node1, node2);
 		if(n == 2) {
 			if(do_graph && req == REQ_DUMP_NODES)
 				continue;
@@ -786,13 +978,90 @@ static int cmd_dump(int argc, char *argv[]) {
 		if(n < 2)
 			break;
 
-		if(!do_graph)
-			printf("%s\n", line + 5);
-		else {
-			if(req == REQ_DUMP_NODES)
-				printf(" %s [label = \"%s\"];\n", node1, node1);
-			else
-				printf(" %s -> %s;\n", node1, node2);
+		char node[4096];
+		char from[4096];
+		char to[4096];
+		char subnet[4096];
+		char host[4096];
+		char port[4096];
+		char via[4096];
+		char nexthop[4096];
+		int cipher, digest, maclength, compression, distance, socket, weight;
+		short int pmtu, minmtu, maxmtu;
+		unsigned int options, status_int;
+		node_status_t status;
+		long int last_state_change;
+
+		switch(req) {
+			case REQ_DUMP_NODES: {
+				int n = sscanf(line, "%*d %*d %s %s port %s %d %d %d %d %x %x %s %s %d %hd %hd %hd %ld", node, host, port, &cipher, &digest, &maclength, &compression, &options, &status_int, nexthop, via, &distance, &pmtu, &minmtu, &maxmtu, &last_state_change);
+				if(n != 16) {
+					fprintf(stderr, "Unable to parse node dump from tincd: %s\n", line);
+					return 1;
+				}
+
+				memcpy(&status, &status_int, sizeof status);
+
+				if(do_graph) {
+					const char *color = "black";
+					if(!strcmp(host, "MYSELF"))
+						color = "green";
+					else if(!status.reachable)
+						color = "red";
+					else if(strcmp(via, node))
+						color = "orange";
+					else if(!status.validkey)
+						color = "black";
+					else if(minmtu > 0)
+						color = "green";
+					printf(" %s [label = \"%s\", color = \"%s\"%s];\n", node, node, color, strcmp(host, "MYSELF") ? "" : ", style = \"filled\"");
+				} else {
+					if(only_reachable && !status.reachable)
+						continue;
+					printf("%s at %s port %s cipher %d digest %d maclength %d compression %d options %x status %04x nexthop %s via %s distance %d pmtu %hd (min %hd max %hd)\n",
+							node, host, port, cipher, digest, maclength, compression, options, status_int, nexthop, via, distance, pmtu, minmtu, maxmtu);
+				}
+			} break;
+
+			case REQ_DUMP_EDGES: {
+				int n = sscanf(line, "%*d %*d %s %s %s port %s %x %d", from, to, host, port, &options, &weight);
+				if(n != 6) {
+					fprintf(stderr, "Unable to parse edge dump from tincd.\n");
+					return 1;
+				}
+
+				if(do_graph) {
+					float w = 1 + 65536.0 / weight;
+					if(do_graph == 1 && strcmp(node1, node2) > 0)
+						printf(" %s -- %s [w = %f, weight = %f];\n", node1, node2, w, w);
+					else if(do_graph == 2)
+						printf(" %s -> %s [w = %f, weight = %f];\n", node1, node2, w, w);
+				} else {
+					printf("%s to %s at %s port %s options %x weight %d\n", from, to, host, port, options, weight);
+				}
+			} break;
+
+			case REQ_DUMP_SUBNETS: {
+				int n = sscanf(line, "%*d %*d %s %s", subnet, node);
+				if(n != 2) {
+					fprintf(stderr, "Unable to parse subnet dump from tincd.\n");
+					return 1;
+				}
+				printf("%s owner %s\n", strip_weight(subnet), node);
+			} break;
+
+			case REQ_DUMP_CONNECTIONS: {
+				int n = sscanf(line, "%*d %*d %s %s port %s %x %d %x", node, host, port, &options, &socket, &status_int);
+				if(n != 6) {
+					fprintf(stderr, "Unable to parse connection dump from tincd.\n");
+					return 1;
+				}
+				printf("%s at %s port %s options %x socket %d status %x\n", node, host, port, options, socket, status_int);
+			} break;
+
+			default:
+				fprintf(stderr, "Unable to parse dump from tincd.\n");
+				return 1;
 		}
 	}
 
@@ -801,7 +1070,7 @@ static int cmd_dump(int argc, char *argv[]) {
 }
 
 static int cmd_purge(int argc, char *argv[]) {
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	sendline(fd, "%d %d", CONTROL, REQ_PURGE);
@@ -819,7 +1088,7 @@ static int cmd_debug(int argc, char *argv[]) {
 		return 1;
 	}
 
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	int debuglevel = atoi(argv[1]);
@@ -836,7 +1105,7 @@ static int cmd_debug(int argc, char *argv[]) {
 }
 
 static int cmd_retry(int argc, char *argv[]) {
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	sendline(fd, "%d %d", CONTROL, REQ_RETRY);
@@ -854,12 +1123,12 @@ static int cmd_connect(int argc, char *argv[]) {
 		return 1;
 	}
 
-	if(!check_id(argv[2])) {
+	if(!check_id(argv[1])) {
 		fprintf(stderr, "Invalid name for node.\n");
 		return 1;
 	}
 
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	sendline(fd, "%d %d %s", CONTROL, REQ_CONNECT, argv[1]);
@@ -877,12 +1146,12 @@ static int cmd_disconnect(int argc, char *argv[]) {
 		return 1;
 	}
 
-	if(!check_id(argv[2])) {
+	if(!check_id(argv[1])) {
 		fprintf(stderr, "Invalid name for node.\n");
 		return 1;
 	}
 
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	sendline(fd, "%d %d %s", CONTROL, REQ_DISCONNECT, argv[1]);
@@ -896,7 +1165,7 @@ static int cmd_disconnect(int argc, char *argv[]) {
 
 static int cmd_top(int argc, char *argv[]) {
 #ifdef HAVE_CURSES
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	top(fd);
@@ -908,7 +1177,7 @@ static int cmd_top(int argc, char *argv[]) {
 }
 
 static int cmd_pcap(int argc, char *argv[]) {
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	pcap(fd, stdout, argc > 1 ? atoi(argv[1]) : 0);
@@ -916,7 +1185,7 @@ static int cmd_pcap(int argc, char *argv[]) {
 }
 
 static int cmd_log(int argc, char *argv[]) {
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	logcontrol(fd, stdout, argc > 1 ? atoi(argv[1]) : -1);
@@ -924,7 +1193,7 @@ static int cmd_log(int argc, char *argv[]) {
 }
 
 static int cmd_pid(int argc, char *argv[]) {
-	if(!connect_tincd())
+	if(!connect_tincd(true) && !pid)
 		return 1;
 
 	printf("%d\n", pid);
@@ -971,12 +1240,75 @@ static char *get_my_name() {
 	return NULL;
 }
 
-static char *hostvariables[] = {
-	"Address",
-	"Port",
-	"PublicKey",
-	"Subnet",
-	NULL,
+#define VAR_SERVER 1    /* Should be in tinc.conf */
+#define VAR_HOST 2      /* Can be in host config file */
+#define VAR_MULTIPLE 4  /* Multiple statements allowed */
+#define VAR_OBSOLETE 8  /* Should not be used anymore */
+
+static struct {
+	const char *name;
+	int type;
+} const variables[] = {
+	/* Server configuration */
+	{"AddressFamily", VAR_SERVER},
+	{"AutoConnect", VAR_SERVER},
+	{"BindToAddress", VAR_SERVER | VAR_MULTIPLE},
+	{"BindToInterface", VAR_SERVER},
+	{"Broadcast", VAR_SERVER},
+	{"ConnectTo", VAR_SERVER | VAR_MULTIPLE},
+	{"DecrementTTL", VAR_SERVER},
+	{"Device", VAR_SERVER},
+	{"DeviceType", VAR_SERVER},
+	{"DirectOnly", VAR_SERVER},
+	{"ECDSAPrivateKeyFile", VAR_SERVER},
+	{"ExperimentalProtocol", VAR_SERVER},
+	{"Forwarding", VAR_SERVER},
+	{"GraphDumpFile", VAR_SERVER | VAR_OBSOLETE},
+	{"Hostnames", VAR_SERVER},
+	{"IffOneQueue", VAR_SERVER},
+	{"Interface", VAR_SERVER},
+	{"KeyExpire", VAR_SERVER},
+	{"LocalDiscovery", VAR_SERVER},
+	{"MACExpire", VAR_SERVER},
+	{"MaxOutputBufferSize", VAR_SERVER},
+	{"MaxTimeout", VAR_SERVER},
+	{"Mode", VAR_SERVER},
+	{"Name", VAR_SERVER},
+	{"PingInterval", VAR_SERVER},
+	{"PingTimeout", VAR_SERVER},
+	{"PriorityInheritance", VAR_SERVER},
+	{"PrivateKey", VAR_SERVER | VAR_OBSOLETE},
+	{"PrivateKeyFile", VAR_SERVER},
+	{"ProcessPriority", VAR_SERVER},
+	{"Proxy", VAR_SERVER},
+	{"ReplayWindow", VAR_SERVER},
+	{"ScriptsExtension", VAR_SERVER},
+	{"ScriptsInterpreter", VAR_SERVER},
+	{"StrictSubnets", VAR_SERVER},
+	{"TunnelServer", VAR_SERVER},
+	{"UDPRcvBuf", VAR_SERVER},
+	{"UDPSndBuf", VAR_SERVER},
+	{"VDEGroup", VAR_SERVER},
+	{"VDEPort", VAR_SERVER},
+	/* Host configuration */
+	{"Address", VAR_HOST | VAR_MULTIPLE},
+	{"Cipher", VAR_SERVER | VAR_HOST},
+	{"ClampMSS", VAR_SERVER | VAR_HOST},
+	{"Compression", VAR_SERVER | VAR_HOST},
+	{"Digest", VAR_SERVER | VAR_HOST},
+	{"ECDSAPublicKey", VAR_HOST},
+	{"ECDSAPublicKeyFile", VAR_SERVER | VAR_HOST},
+	{"IndirectData", VAR_SERVER | VAR_HOST},
+	{"MACLength", VAR_SERVER | VAR_HOST},
+	{"PMTU", VAR_SERVER | VAR_HOST},
+	{"PMTUDiscovery", VAR_SERVER | VAR_HOST},
+	{"Port", VAR_HOST},
+	{"PublicKey", VAR_HOST | VAR_OBSOLETE},
+	{"PublicKeyFile", VAR_SERVER | VAR_HOST | VAR_OBSOLETE},
+	{"Subnet", VAR_HOST | VAR_MULTIPLE},
+	{"TCPOnly", VAR_SERVER | VAR_HOST},
+	{"Weight", VAR_HOST},
+	{NULL, 0}
 };
 
 static int cmd_config(int argc, char *argv[]) {
@@ -985,8 +1317,10 @@ static int cmd_config(int argc, char *argv[]) {
 		return 1;
 	}
 
-	int action = 0;
-	if(!strcasecmp(argv[1], "add")) {
+	int action = -2;
+	if(!strcasecmp(argv[1], "get")) {
+		argv++, argc--;
+	} else if(!strcasecmp(argv[1], "add")) {
 		argv++, argc--, action = 1;
 	} else if(!strcasecmp(argv[1], "del")) {
 		argv++, argc--, action = -1;
@@ -1012,14 +1346,14 @@ static int cmd_config(int argc, char *argv[]) {
 	char *value;
 	int len;
 
-        len = strcspn(line, "\t =");
-        value = line + len;
-        value += strspn(value, "\t ");
-        if(*value == '=') {
-                value++;
-                value += strspn(value, "\t ");
-        }
-        line[len] = '\0';
+	len = strcspn(line, "\t =");
+	value = line + len;
+	value += strspn(value, "\t ");
+	if(*value == '=') {
+		value++;
+		value += strspn(value, "\t ");
+	}
+	line[len] = '\0';
 	variable = strchr(line, '.');
 	if(variable) {
 		node = line;
@@ -1038,16 +1372,50 @@ static int cmd_config(int argc, char *argv[]) {
 		return 1;
 	}
 
-	// Should this go into our own host config file?
-	if(!node) {
-		for(int i = 0; hostvariables[i]; i++) {
-			if(!strcasecmp(hostvariables[i], variable)) {
-				node = get_my_name();
-				if(!node)
-					return 1;
-				break;
+	if(action < -1 && *value)
+		action = 0;
+
+	/* Some simple checks. */
+	bool found = false;
+
+	for(int i = 0; variables[i].name; i++) {
+		if(strcasecmp(variables[i].name, variable))
+			continue;
+
+		found = true;
+		variable = (char *)variables[i].name;
+
+		/* Discourage use of obsolete variables. */
+
+		if(variables[i].type & VAR_OBSOLETE && action >= 0) {
+			if(force) {
+				fprintf(stderr, "Warning: %s is an obsolete variable!\n", variable);
+			} else {
+				fprintf(stderr, "%s is an obsolete variable! Use --force to use it anyway.\n", variable);
+				return 1;
 			}
 		}
+
+		/* Don't put server variables in host config files */
+
+		if(node && !(variables[i].type & VAR_HOST) && action >= 0) {
+			if(force) {
+				fprintf(stderr, "Warning: %s is not a host configuration variable!\n", variable);
+			} else {
+				fprintf(stderr, "%s is not a host configuration variable! Use --force to use it anyway.\n", variable);
+				return 1;
+			}
+		}
+
+		/* Should this go into our own host config file? */
+
+		if(!node && !(variables[i].type & VAR_SERVER)) {
+			node = get_my_name();
+			if(!node)
+				return 1;
+		}
+
+		break;
 	}
 
 	if(node && !check_id(node)) {
@@ -1055,10 +1423,19 @@ static int cmd_config(int argc, char *argv[]) {
 		return 1;
 	}
 
+	if(!found) {
+		if(force || action < 0) {
+			fprintf(stderr, "Warning: %s is not a known configuration variable!\n", variable);
+		} else {
+			fprintf(stderr, "%s: is not a known configuration variable! Use --force to use it anyway.\n", variable);
+			return 1;
+		}
+	}
+
 	// Open the right configuration file.
 	char *filename;
 	if(node)
-		xasprintf(&filename, "%s/%s", hosts_dir, node);
+		xasprintf(&filename, "%s" SLASH "%s", hosts_dir, node);
 	else
 		filename = tinc_conf;
 
@@ -1079,23 +1456,29 @@ static int cmd_config(int argc, char *argv[]) {
 		}
 	}
 
-	char *tmpfile;
-	xasprintf(&tmpfile, "%s.config.tmp", filename);
-	FILE *tf = fopen(tmpfile, "w");
-	if(!tf) {
-		fprintf(stderr, "Could not open temporary file %s: %s\n", tmpfile, strerror(errno));
-		return 1;
+	char *tmpfile = NULL;
+	FILE *tf = NULL;
+
+	if(action >= -1) {
+		xasprintf(&tmpfile, "%s.config.tmp", filename);
+		tf = fopen(tmpfile, "w");
+		if(!tf) {
+			fprintf(stderr, "Could not open temporary file %s: %s\n", tmpfile, strerror(errno));
+			fclose(f);
+			return 1;
+		}
 	}
 
-	// Copy the file, making modifications on the fly.
+	// Copy the file, making modifications on the fly, unless we are just getting a value.
 	char buf1[4096];
 	char buf2[4096];
 	bool set = false;
 	bool removed = false;
+	found = false;
 
 	while(fgets(buf1, sizeof buf1, f)) {
 		buf1[sizeof buf1 - 1] = 0;
-		strcpy(buf2, buf1);
+		strncpy(buf2, buf1, sizeof buf2);
 
 		// Parse line in a simple way
 		char *bvalue;
@@ -1113,8 +1496,12 @@ static int cmd_config(int argc, char *argv[]) {
 
 		// Did it match?
 		if(!strcasecmp(buf2, variable)) {
+			// Get
+			if(action < -1) {
+				found = true;
+				printf("%s\n", bvalue);
 			// Del
-			if(action < 0) {
+			} else if(action == -1) {
 				if(!*value || !strcasecmp(bvalue, value)) {
 					removed = true;
 					continue;
@@ -1134,10 +1521,20 @@ static int cmd_config(int argc, char *argv[]) {
 			}
 		}
 
-		// Copy original line...
-		if(fputs(buf1, tf) < 0) {
-			fprintf(stderr, "Error writing to temporary file %s: %s\n", tmpfile, strerror(errno));
-			return 1;
+		if(action >= -1) {
+			// Copy original line...
+			if(fputs(buf1, tf) < 0) {
+				fprintf(stderr, "Error writing to temporary file %s: %s\n", tmpfile, strerror(errno));
+				return 1;
+			}
+
+			// Add newline if it is missing...
+			if(*buf1 && buf1[strlen(buf1) - 1] != '\n') {
+				if(fputc('\n', tf) < 0) {
+					fprintf(stderr, "Error writing to temporary file %s: %s\n", tmpfile, strerror(errno));
+					return 1;
+				}
+			}
 		}
 	}
 
@@ -1160,6 +1557,12 @@ static int cmd_config(int argc, char *argv[]) {
 		}
 	}
 
+	if(action < -1) {
+		if(!found)
+			fprintf(stderr, "No matching configuration variables found.\n");
+		return 0;
+	}
+
 	// Make sure we wrote everything...
 	if(fclose(tf)) {
 		fprintf(stderr, "Error closing temporary file %s: %s\n", tmpfile, strerror(errno));
@@ -1186,15 +1589,16 @@ static int cmd_config(int argc, char *argv[]) {
 	}
 
 	// Silently try notifying a running tincd of changes.
-	fclose(stderr);
-
-	if(connect_tincd())
+	if(connect_tincd(false))
 		sendline(fd, "%d %d", CONTROL, REQ_RELOAD);
 
 	return 0;
 }
 
 bool check_id(const char *name) {
+	if(!name || !*name)
+		return false;
+
 	for(int i = 0; i < strlen(name); i++) {
 		if(!isalnum(name[i]) && name[i] != '_')
 			return false;
@@ -1210,7 +1614,7 @@ static int cmd_init(int argc, char *argv[]) {
 	}
 
 	if(argc < 2) {
-		if(isatty(0) && isatty(1)) {
+		if(tty) {
 			char buf[1024];
 			fprintf(stdout, "Enter the Name you want your tinc node to have: ");
 			fflush(stdout);
@@ -1241,7 +1645,7 @@ static int cmd_init(int argc, char *argv[]) {
 		return 1;
 	}
 
-	if(mkdir(CONFDIR, 0755) && errno != EEXIST) {
+	if(mkdir(confdir, 0755) && errno != EEXIST) {
 		fprintf(stderr, "Could not create directory %s: %s\n", CONFDIR, strerror(errno));
 		return 1;
 	}
@@ -1251,8 +1655,6 @@ static int cmd_init(int argc, char *argv[]) {
 		return 1;
 	}
 
-	char *hosts_dir = NULL;
-	xasprintf(&hosts_dir, "%s/hosts", confbase);
 	if(mkdir(hosts_dir, 0755) && errno != EEXIST) {
 		fprintf(stderr, "Could not create directory %s: %s\n", hosts_dir, strerror(errno));
 		return 1;
@@ -1267,24 +1669,38 @@ static int cmd_init(int argc, char *argv[]) {
 	fprintf(f, "Name = %s\n", name);
 	fclose(f);
 
-	fclose(stdin);
-	if(!rsa_keygen(2048) || !ecdsa_keygen())
-		return false;
+	if(!rsa_keygen(2048, false) || !ecdsa_keygen(false))
+		return 1;
 
-	return true;
+#ifndef HAVE_MINGW
+	char *filename;
+	xasprintf(&filename, "%s" SLASH "tinc-up", confbase);
+	if(access(filename, F_OK)) {
+		FILE *f = fopen(filename, "w");
+		if(!f) {
+			fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
+			return 1;
+		}
+		fchmod(fileno(f), 0755);
+		fprintf(f, "#!/bin/sh\n\necho 'Unconfigured tinc-up script, please edit!'\n\n#ifconfig $INTERFACE <your vpn IP address> netmask <netmask of whole VPN>\n");
+		fclose(f);
+	}
+#endif
+
+	return 0;
 
 }
 
 static int cmd_generate_keys(int argc, char *argv[]) {
-	return !(rsa_keygen(argc > 1 ? atoi(argv[1]) : 2048) && ecdsa_keygen());
+	return !(rsa_keygen(argc > 1 ? atoi(argv[1]) : 2048, true) && ecdsa_keygen(true));
 }
 
 static int cmd_generate_rsa_keys(int argc, char *argv[]) {
-	return !rsa_keygen(argc > 1 ? atoi(argv[1]) : 2048);
+	return !rsa_keygen(argc > 1 ? atoi(argv[1]) : 2048, true);
 }
 
 static int cmd_generate_ecdsa_keys(int argc, char *argv[]) {
-	return !ecdsa_keygen();
+	return !ecdsa_keygen(true);
 }
 
 static int cmd_help(int argc, char *argv[]) {
@@ -1303,7 +1719,7 @@ static int cmd_info(int argc, char *argv[]) {
 		return 1;
 	}
 
-	if(!connect_tincd())
+	if(!connect_tincd(true))
 		return 1;
 
 	return info(fd, argv[1]);
@@ -1328,10 +1744,10 @@ static int cmd_edit(int argc, char *argv[]) {
 
 	char *filename = NULL;
 
-	if(strncmp(argv[1], "hosts/", 6)) {
+	if(strncmp(argv[1], "hosts" SLASH, 6)) {
 		for(int i = 0; conffiles[i]; i++) {
 			if(!strcmp(argv[1], conffiles[i])) {
-				xasprintf(&filename, "%s/%s", confbase, argv[1]);
+				xasprintf(&filename, "%s" SLASH "%s", confbase, argv[1]);
 				break;
 			}
 		}
@@ -1340,7 +1756,7 @@ static int cmd_edit(int argc, char *argv[]) {
 	}
 
 	if(!filename) {
-		xasprintf(&filename, "%s/%s", hosts_dir, argv[1]);
+		xasprintf(&filename, "%s" SLASH "%s", hosts_dir, argv[1]);
 		char *dash = strchr(argv[1], '-');
 		if(dash) {
 			*dash++ = 0;
@@ -1351,22 +1767,18 @@ static int cmd_edit(int argc, char *argv[]) {
 		}
 	}
 
+	char *command;
 #ifndef HAVE_MINGW
-	char *editor = getenv("VISUAL") ?: getenv("EDITOR") ?: "vi";
+	xasprintf(&command, "\"%s\" \"%s\"", getenv("VISUAL") ?: getenv("EDITOR") ?: "vi", filename);
 #else
-	char *editor = "edit"
+	xasprintf(&command, "edit \"%s\"", filename);
 #endif
-
-	char *command;
-	xasprintf(&command, "\"%s\" \"%s\"", editor, filename);
 	int result = system(command);
 	if(result)
 		return result;
 
 	// Silently try notifying a running tincd of changes.
-	fclose(stderr);
-
-	if(connect_tincd())
+	if(connect_tincd(false))
 		sendline(fd, "%d %d", CONTROL, REQ_RELOAD);
 
 	return 0;
@@ -1374,7 +1786,7 @@ static int cmd_edit(int argc, char *argv[]) {
 
 static int export(const char *name, FILE *out) {
 	char *filename;
-	xasprintf(&filename, "%s/%s", hosts_dir, name);
+	xasprintf(&filename, "%s" SLASH "%s", hosts_dir, name);
 	FILE *in = fopen(filename, "r");
 	if(!in) {
 		fprintf(stderr, "Could not open configuration file %s: %s\n", filename, strerror(errno));
@@ -1390,6 +1802,7 @@ static int export(const char *name, FILE *out) {
 
 	if(ferror(in)) {
 		fprintf(stderr, "Error while reading configuration file %s: %s\n", filename, strerror(errno));
+		fclose(in);
 		return 1;
 	}
 
@@ -1453,7 +1866,7 @@ static int cmd_import(int argc, char *argv[]) {
 				fclose(out);
 
 			free(filename);
-			xasprintf(&filename, "%s/%s", hosts_dir, name);
+			xasprintf(&filename, "%s" SLASH "%s", hosts_dir, name);
 
 			if(!force && !access(filename, F_OK)) {
 				fprintf(stderr, "Host configuration file %s already exists, skipping.\n", filename);
@@ -1532,12 +1945,249 @@ static const struct {
 	{NULL, NULL},
 };
 
+#ifdef HAVE_READLINE
+static char *complete_command(const char *text, int state) {
+	static int i;
+
+	if(!state)
+		i = 0;
+	else
+		i++;
+
+	while(commands[i].command) {
+		if(!strncasecmp(commands[i].command, text, strlen(text)))
+			return xstrdup(commands[i].command);
+		i++;
+	}
+
+	return NULL;
+}
+
+static char *complete_dump(const char *text, int state) {
+	const char *matches[] = {"reachable", "nodes", "edges", "subnets", "connections", "graph", NULL};
+	static int i;
+
+	if(!state)
+		i = 0;
+	else
+		i++;
+
+	while(matches[i]) {
+		if(!strncasecmp(matches[i], text, strlen(text)))
+			return xstrdup(matches[i]);
+		i++;
+	}
+
+	return NULL;
+}
+
+static char *complete_config(const char *text, int state) {
+	const char *sub[] = {"get", "set", "add", "del"};
+	static int i;
+	if(!state) {
+		i = 0;
+		if(!strchr(rl_line_buffer + 7, ' '))
+			i = -4;
+		else {
+			bool found = false;
+			for(int i = 0; i < 4; i++) {
+				if(!strncasecmp(rl_line_buffer + 7, sub[i], strlen(sub[i])) && rl_line_buffer[7 + strlen(sub[i])] == ' ') {
+					found = true;
+					break;
+				}
+			}
+			if(!found)
+				return NULL;
+		}
+	} else {
+		i++;
+	}
+
+	while(i < 0 || variables[i].name) {
+		if(i < 0 && !strncasecmp(sub[i + 4], text, strlen(text)))
+			return xstrdup(sub[i + 4]);
+		if(i >= 0) {
+			char *dot = strchr(text, '.');
+			if(dot) {
+				if((variables[i].type & VAR_HOST) && !strncasecmp(variables[i].name, dot + 1, strlen(dot + 1))) {
+					char *match;
+					xasprintf(&match, "%.*s.%s", dot - text, text, variables[i].name);
+					return match;
+				}
+			} else {
+				if(!strncasecmp(variables[i].name, text, strlen(text)))
+					return xstrdup(variables[i].name);
+			}
+		}
+		i++;
+	}
+
+	return NULL;
+}
+
+static char *complete_info(const char *text, int state) {
+	static int i;
+	if(!state) {
+		i = 0;
+		if(!connect_tincd(false))
+			return NULL;
+		// Check the list of nodes
+		sendline(fd, "%d %d", CONTROL, REQ_DUMP_NODES);
+		sendline(fd, "%d %d", CONTROL, REQ_DUMP_SUBNETS);
+	}
+
+	while(recvline(fd, line, sizeof line)) {
+		char item[4096];
+		int n = sscanf(line, "%d %d %s", &code, &req, item);
+		if(n == 2) {
+			i++;
+			if(i >= 2)
+				break;
+			else
+				continue;
+		}
+
+		if(n != 3) {
+			fprintf(stderr, "Unable to parse dump from tincd, n = %d, i = %d.\n", n, i);
+			break;
+		}
+
+		if(!strncmp(item, text, strlen(text)))
+			return xstrdup(strip_weight(item));
+	}
+
+	return NULL;
+}
+
+static char *complete_nothing(const char *text, int state) {
+	return NULL;
+}
+
+static char **completion (const char *text, int start, int end) {
+	char **matches = NULL;
+
+	if(!start)
+		matches = rl_completion_matches(text, complete_command);
+	else if(!strncasecmp(rl_line_buffer, "dump ", 5))
+		matches = rl_completion_matches(text, complete_dump);
+	else if(!strncasecmp(rl_line_buffer, "config ", 7))
+		matches = rl_completion_matches(text, complete_config);
+	else if(!strncasecmp(rl_line_buffer, "info ", 5))
+		matches = rl_completion_matches(text, complete_info);
+
+	return matches;
+}
+#endif
+
+static int cmd_shell(int argc, char *argv[]) {
+	char *prompt;
+	xasprintf(&prompt, "%s> ", identname);
+	int result = 0;
+	char buf[4096];
+	char *line = NULL;
+	int maxargs = argc + 16;
+	char **nargv = xmalloc(maxargs * sizeof *nargv);
+
+	for(int i = 0; i < argc; i++)
+		nargv[i] = argv[i];
+
+#ifdef HAVE_READLINE
+	rl_readline_name = "tinc";
+	rl_completion_entry_function = complete_nothing;
+	rl_attempted_completion_function = completion;
+	rl_filename_completion_desired = 0;
+	char *copy = NULL;
+#endif
+
+	while(true) {
+#ifdef HAVE_READLINE
+		if(tty) {
+			free(copy);
+			free(line);
+			rl_basic_word_break_characters = "\t\n ";
+			line = readline(prompt);
+			if(line)
+				copy = xstrdup(line);
+		} else {
+			line = fgets(buf, sizeof buf, stdin);
+		}
+#else
+		if(tty)
+			fputs(prompt, stdout);
+
+		line = fgets(buf, sizeof buf, stdin);
+#endif
+
+		if(!line)
+			break;
+
+		/* Ignore comments */
+
+		if(*line == '#')
+			continue;
+
+		/* Split */
+
+		int nargc = argc;
+		char *p = line + strspn(line, " \t\n");
+		char *next = strtok(p, " \t\n");
+
+		while(p && *p) {
+			if(nargc >= maxargs) {
+				fprintf(stderr, "next %p '%s', p %p '%s'\n", next, next, p, p);
+				abort();
+				maxargs *= 2;
+				nargv = xrealloc(nargv, maxargs * sizeof *nargv);
+			}
+
+			nargv[nargc++] = p;
+			p = next;
+			next = strtok(NULL, " \t\n");
+		}
+
+		if(nargc == argc)
+			continue;
+
+		if(!strcasecmp(nargv[argc], "exit") || !strcasecmp(nargv[argc], "quit"))
+			return result;
+
+		bool found = false;
+
+		for(int i = 0; commands[i].command; i++) {
+			if(!strcasecmp(nargv[argc], commands[i].command)) {
+				result |= commands[i].function(nargc - argc - 1, nargv + argc + 1);
+				found = true;
+				break;
+			}
+		}
+
+#ifdef HAVE_READLINE
+		if(tty && found)
+			add_history(copy);
+#endif
+
+		if(!found) {
+			fprintf(stderr, "Unknown command `%s'.\n", nargv[argc]);
+			result |= 1;
+		}
+	}
+
+	free(nargv);
+
+	if(tty)
+		printf("\n");
+	return result;
+}
+
+
 int main(int argc, char *argv[]) {
 	program_name = argv[0];
+	orig_argv = argv;
+	orig_argc = argc;
 
 	if(!parse_options(argc, argv))
 		return 1;
-	
+
 	make_names();
 
 	if(show_version) {
@@ -1550,11 +2200,10 @@ int main(int argc, char *argv[]) {
 		return 0;
 	}
 
-	if(optind >= argc) {
-		fprintf(stderr, "No command given.\n");
-		usage(true);
-		return 1;
-	}
+	tty = isatty(0) && isatty(1);
+
+	if(optind >= argc)
+		return cmd_shell(argc, argv);
 
 	for(int i = 0; commands[i].command; i++) {
 		if(!strcasecmp(argv[optind], commands[i].command))