Add option to dump only a list of reachable nodes.
[tinc] / src / tincctl.c
index 1cdcf58..dd0bbcc 100644 (file)
 
 #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"
 #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;
 
@@ -45,14 +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 *identname = NULL;          /* program name for syslog */
+static char *pidfilename = NULL;        /* pid file location */
 static char *confdir = NULL;
-static char controlcookie[1024];
+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;
@@ -62,6 +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;
@@ -111,6 +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"
@@ -123,11 +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"
@@ -152,34 +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;
 
@@ -188,27 +200,109 @@ static bool parse_options(int argc, char **argv) {
                }
        }
 
-        if(!netname && (netname = getenv("NETNAME")))
-                netname = xstrdup(netname);
+       if(!netname && (netname = getenv("NETNAME")))
+               netname = xstrdup(netname);
 
-        /* netname "." is special: a "top-level name" */
+       /* netname "." is special: a "top-level name" */
 
-        if(netname && !strcmp(netname, ".")) {
-                free(netname);
-                netname = NULL;
-        }
+       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);
@@ -239,7 +333,9 @@ static FILE *ask_and_open(const char *filename, const char *what, const char *mo
                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 */
 
@@ -257,10 +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");
 
@@ -270,44 +366,38 @@ static bool ecdsa_keygen() {
        } else
                fprintf(stderr, "Done.\n");
 
-       xasprintf(&filename, "%s" SLASH "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" SLASH "hosts" SLASH "%s", confbase, name);
+               xasprintf(&pubname, "%s" SLASH "hosts" SLASH "%s", confbase, name);
        else
-               xasprintf(&filename, "%s" SLASH "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;
 }
@@ -316,10 +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);
 
@@ -329,42 +419,36 @@ static bool rsa_keygen(int bits) {
        } else
                fprintf(stderr, "Done.\n");
 
-       xasprintf(&filename, "%s" SLASH "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" SLASH "hosts" SLASH "%s", confbase, name);
+               xasprintf(&pubname, "%s" SLASH "hosts" SLASH "%s", confbase, name);
        else
-               xasprintf(&filename, "%s" SLASH "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;
 }
@@ -496,7 +580,7 @@ bool sendline(int fd, char *format, ...) {
                blen -= result;
        }
 
-       return true;    
+       return true;
 }
 
 static void pcap(int fd, FILE *out, int snaplen) {
@@ -603,27 +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
@@ -638,13 +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;
        }
 
@@ -652,12 +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;
        }
 
@@ -667,14 +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;
        }
 
@@ -683,42 +796,74 @@ 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++)
-               xasprintf(&c, "%.*stincd", (int)(slash - argv[0]), argv[0]);
+               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)) 
+                       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;
                }
 
@@ -730,19 +875,30 @@ static int cmd_stop(int argc, char *argv[]) {
                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);
@@ -756,16 +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);
@@ -778,19 +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;
@@ -803,13 +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;
                }
        }
 
@@ -818,7 +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);
@@ -836,7 +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]);
@@ -853,7 +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);
@@ -871,12 +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]);
@@ -894,12 +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]);
@@ -913,7 +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);
@@ -925,7 +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);
@@ -933,7 +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);
@@ -941,7 +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);
@@ -999,6 +1251,7 @@ static struct {
 } const variables[] = {
        /* Server configuration */
        {"AddressFamily", VAR_SERVER},
+       {"AutoConnect", VAR_SERVER},
        {"BindToAddress", VAR_SERVER | VAR_MULTIPLE},
        {"BindToInterface", VAR_SERVER},
        {"Broadcast", VAR_SERVER},
@@ -1010,13 +1263,14 @@ static struct {
        {"ECDSAPrivateKeyFile", VAR_SERVER},
        {"ExperimentalProtocol", VAR_SERVER},
        {"Forwarding", VAR_SERVER},
-       {"GraphDumpFile", 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},
@@ -1026,26 +1280,34 @@ static struct {
        {"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_SERVER | VAR_HOST | VAR_OBSOLETE},
+       {"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}
 };
 
@@ -1055,8 +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;
@@ -1082,14 +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;
@@ -1108,6 +1372,9 @@ static int cmd_config(int argc, char *argv[]) {
                return 1;
        }
 
+       if(action < -1 && *value)
+               action = 0;
+
        /* Some simple checks. */
        bool found = false;
 
@@ -1156,8 +1423,8 @@ static int cmd_config(int argc, char *argv[]) {
                return 1;
        }
 
-       if(!found && action >= 0) {
-               if(force) {
+       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);
@@ -1189,19 +1456,25 @@ 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;
@@ -1223,8 +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;
@@ -1244,18 +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;
-               }
-
-               // Add newline if it is missing...
-               if(*buf1 && buf1[strlen(buf1) - 1] != '\n') {
-                       if(fputc('\n', tf) < 0) {
+               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;
+                               }
+                       }
                }
        }
 
@@ -1278,6 +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));
@@ -1304,15 +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;
@@ -1328,7 +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);
@@ -1383,8 +1669,7 @@ static int cmd_init(int argc, char *argv[]) {
        fprintf(f, "Name = %s\n", name);
        fclose(f);
 
-       fclose(stdin);
-       if(!rsa_keygen(2048) || !ecdsa_keygen())
+       if(!rsa_keygen(2048, false) || !ecdsa_keygen(false))
                return 1;
 
 #ifndef HAVE_MINGW
@@ -1407,15 +1692,15 @@ static int cmd_init(int argc, char *argv[]) {
 }
 
 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[]) {
@@ -1434,7 +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]);
@@ -1493,9 +1778,7 @@ static int cmd_edit(int argc, char *argv[]) {
                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;
@@ -1519,6 +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;
        }
 
@@ -1661,12 +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) {
@@ -1679,11 +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))