Make tincctl robust against dropped control connections.
[tinc] / src / tincctl.c
index a515259..0d773e4 100644 (file)
@@ -138,7 +138,7 @@ static void usage(bool status) {
                                "    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"
@@ -217,6 +217,83 @@ static bool parse_options(int argc, char **argv) {
        return true;
 }
 
+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;
@@ -257,6 +334,8 @@ static FILE *ask_and_open(const char *filename, const char *what, const char *mo
 
        umask(0077);                            /* Disallow everything for group and other */
 
+       disable_old_keys(filename, what);
+
        /* Open it first to keep the inode busy */
 
        r = fopen(filename, mode);
@@ -297,9 +376,6 @@ static bool ecdsa_keygen(bool ask) {
        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);
@@ -315,9 +391,6 @@ static bool ecdsa_keygen(bool ask) {
        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);
@@ -356,9 +429,6 @@ static bool rsa_keygen(int bits, bool ask) {
        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);
@@ -374,9 +444,6 @@ static bool rsa_keygen(int bits, bool ask) {
        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);
@@ -620,8 +687,19 @@ static bool remove_service(void) {
 #endif
 
 static bool connect_tincd(bool verbose) {
-       if(fd >= 0)
-               return true;
+       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) {
@@ -684,6 +762,8 @@ static bool connect_tincd(bool verbose) {
        if(connect(fd, res->ai_addr, res->ai_addrlen) < 0) {
                if(verbose)
                        fprintf(stderr, "Cannot connect to %s port %s: %s\n", host, port, sockstrerror(sockerrno));
+               close(fd);
+               fd = -1;
                return false;
        }
 
@@ -695,6 +775,8 @@ static bool connect_tincd(bool verbose) {
        if(!recvline(fd, line, sizeof line) || sscanf(line, "%d %s %d", &code, data, &version) != 3 || code != 0) {
                if(verbose)
                        fprintf(stderr, "Cannot read greeting from control socket: %s\n", sockstrerror(sockerrno));
+               close(fd);
+               fd = -1;
                return false;
        }
 
@@ -703,6 +785,8 @@ static bool connect_tincd(bool verbose) {
        if(!recvline(fd, line, sizeof line) || sscanf(line, "%d %d %d", &code, &version, &pid) != 3 || code != 4 || version != TINC_CTL_VERSION_CURRENT) {
                if(verbose)
                        fprintf(stderr, "Could not fully establish control socket connection\n");
+               close(fd);
+               fd = -1;
                return false;
        }
 
@@ -822,7 +906,7 @@ static int cmd_dump(int argc, char *argv[]) {
        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);
@@ -835,19 +919,25 @@ 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;
@@ -860,13 +950,71 @@ static int cmd_dump(int argc, char *argv[]) {
                if(n < 2)
                        break;
 
-               if(!do_graph)
-                       printf("%s\n", line + 5);
-               else {
+               if(!do_graph) {
+                       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;
+                       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, 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;
+                                       }
+                                       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, 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;
+                                       }
+                                       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);
+                                       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);
+                               } break;
+
+                               default:
+                                       fprintf(stderr, "Unable to parse dump from tincd.\n");
+                                       return 1;
+                       }
+               } else {
                        if(req == REQ_DUMP_NODES)
                                printf(" %s [label = \"%s\"];\n", node1, node1);
-                       else
-                               printf(" %s -> %s;\n", node1, node2);
+                       else {
+                               if(do_graph == 1 && strcmp(node1, node2) > 0)
+                                       printf(" %s -- %s;\n", node1, node2);
+                               else if(do_graph == 2)
+                                       printf(" %s -> %s;\n", node1, node2);
+                       }
                }
        }
 
@@ -928,7 +1076,7 @@ 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;
        }
@@ -951,7 +1099,7 @@ 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;
        }
@@ -1916,7 +2064,7 @@ static int cmd_shell(int argc, char *argv[]) {
                }
 #else
                if(tty)
-                       fputs(stdout, prompt);
+                       fputs(prompt, stdout);
 
                line = fgets(buf, sizeof buf, stdin);
 #endif
@@ -1951,6 +2099,9 @@ static int cmd_shell(int argc, char *argv[]) {
                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++) {
@@ -1962,7 +2113,7 @@ static int cmd_shell(int argc, char *argv[]) {
                }
 
 #ifdef HAVE_READLINE
-               if(found)
+               if(tty && found)
                        add_history(copy);
 #endif