Exemplo n.º 1
0
static bool upgrade_h(connection_t *c, const char *request) {
	char pubkey[MAX_STRING_SIZE];

	if(sscanf(request, "%*d " MAX_STRING, pubkey) != 1) {
		logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ACK", c->name, c->hostname);
		return false;
	}

	if(ecdsa_active(c->ecdsa) || read_ecdsa_public_key(c)) {
		char *knownkey = ecdsa_get_base64_public_key(c->ecdsa);
		bool different = strcmp(knownkey, pubkey);
		free(knownkey);
		if(different) {
			logger(DEBUG_ALWAYS, LOG_ERR, "Already have an Ed25519 public key from %s (%s) which is different from the one presented now!", c->name, c->hostname);
			return false;
		}
		logger(DEBUG_ALWAYS, LOG_INFO, "Already have Ed25519 public key from %s (%s), ignoring.", c->name, c->hostname);
		c->allow_request = TERMREQ;
		return send_termreq(c);
	}

	c->ecdsa = ecdsa_set_base64_public_key(pubkey);
	if(!c->ecdsa) {
		logger(DEBUG_ALWAYS, LOG_INFO, "Got bad Ed25519 public key from %s (%s), not upgrading.", c->name, c->hostname);
		return false;
	}

	logger(DEBUG_ALWAYS, LOG_INFO, "Got Ed25519 public key from %s (%s), upgrading!", c->name, c->hostname);
	append_config_file(c->name, "Ed25519PublicKey", pubkey);
	c->allow_request = TERMREQ;
	return send_termreq(c);
}
Exemplo n.º 2
0
static bool send_upgrade(connection_t *c) {
	/* Special case when protocol_minor is 1: the other end is Ed25519 capable,
	 * but doesn't know our key yet. So send it now. */

	char *pubkey = ecdsa_get_base64_public_key(myself->connection->ecdsa);

	if(!pubkey)
		return false;

	bool result = send_request(c, "%d %s", ACK, pubkey);
	free(pubkey);
	return result;
}
Exemplo n.º 3
0
bool id_h(connection_t *c, const char *request) {
	char name[MAX_STRING_SIZE];

	if(sscanf(request, "%*d " MAX_STRING " %d.%d", name, &c->protocol_major, &c->protocol_minor) < 2) {
		logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ID", c->name,
			   c->hostname);
		return false;
	}

	/* Check if this is a control connection */

	if(name[0] == '^' && !strcmp(name + 1, controlcookie)) {
		c->status.control = true;
		c->allow_request = CONTROL;
		c->last_ping_time = now.tv_sec + 3600;

		free(c->name);
		c->name = xstrdup("<control>");

		return send_request(c, "%d %d %d", ACK, TINC_CTL_VERSION_CURRENT, getpid());
	}

	if(name[0] == '?') {
		if(!invitation_key) {
			logger(DEBUG_ALWAYS, LOG_ERR, "Got invitation from %s but we don't have an invitation key", c->hostname);
			return false;
		}

		c->ecdsa = ecdsa_set_base64_public_key(name + 1);
		if(!c->ecdsa) {
			logger(DEBUG_ALWAYS, LOG_ERR, "Got bad invitation from %s", c->hostname);
			return false;
		}

		c->status.invitation = true;
		char *mykey = ecdsa_get_base64_public_key(invitation_key);
		if(!mykey)
			return false;
		if(!send_request(c, "%d %s", ACK, mykey))
			return false;
		free(mykey);

		c->protocol_minor = 2;

		return sptps_start(&c->sptps, c, false, false, invitation_key, c->ecdsa, "tinc invitation", 15, send_meta_sptps, receive_invitation_sptps);
	}

	/* Check if identity is a valid name */

	if(!check_id(name)) {
		logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ID", c->name,
			   c->hostname, "invalid name");
		return false;
	}

	/* If this is an outgoing connection, make sure we are connected to the right host */

	if(c->outgoing) {
		if(strcmp(c->name, name)) {
			logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s is %s instead of %s", c->hostname, name,
				   c->name);
			return false;
		}
	} else {
		if(c->name)
			free(c->name);
		c->name = xstrdup(name);
	}

	/* Check if version matches */

	if(c->protocol_major != myself->connection->protocol_major) {
		logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s (%s) uses incompatible version %d.%d",
			c->name, c->hostname, c->protocol_major, c->protocol_minor);
		return false;
	}

	if(bypass_security) {
		if(!c->config_tree)
			init_configuration(&c->config_tree);
		c->allow_request = ACK;
		return send_ack(c);
	}

	if(!experimental)
		c->protocol_minor = 0;

	if(!c->config_tree) {
		init_configuration(&c->config_tree);

		if(!read_host_config(c->config_tree, c->name)) {
			logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s had unknown identity (%s)", c->hostname, c->name);
			return false;
		}

		if(experimental)
			read_ecdsa_public_key(c);
			/* Ignore failures if no key known yet */
	}

	if(c->protocol_minor && !ecdsa_active(c->ecdsa))
		c->protocol_minor = 1;

	/* Forbid version rollback for nodes whose Ed25519 key we know */

	if(ecdsa_active(c->ecdsa) && c->protocol_minor < 2) {
		logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s (%s) tries to roll back protocol version to %d.%d",
			c->name, c->hostname, c->protocol_major, c->protocol_minor);
		return false;
	}

	c->allow_request = METAKEY;

	if(c->protocol_minor >= 2) {
		c->allow_request = ACK;
		char label[25 + strlen(myself->name) + strlen(c->name)];

		if(c->outgoing)
			snprintf(label, sizeof label, "tinc TCP key expansion %s %s", myself->name, c->name);
		else
			snprintf(label, sizeof label, "tinc TCP key expansion %s %s", c->name, myself->name);

		return sptps_start(&c->sptps, c, c->outgoing, false, myself->connection->ecdsa, c->ecdsa, label, sizeof label, send_meta_sptps, receive_meta_sptps);
	} else {
		return send_metakey(c);
	}
}
Exemplo n.º 4
0
static bool receive_invitation_sptps(void *handle, uint8_t type, const void *data, uint16_t len) {
	connection_t *c = handle;

	if(type == 128)
		return true;

	if(type == 1 && c->status.invitation_used)
		return finalize_invitation(c, data, len);

	if(type != 0 || len != 18 || c->status.invitation_used)
		return false;

	// Recover the filename from the cookie and the key
	digest_t *digest = digest_open_by_name("sha256", 18);
	if(!digest)
		abort();
	char *fingerprint = ecdsa_get_base64_public_key(invitation_key);
	char hashbuf[18 + strlen(fingerprint)];
	char cookie[25];
	memcpy(hashbuf, data, 18);
	memcpy(hashbuf + 18, fingerprint, sizeof hashbuf - 18);
	digest_create(digest, hashbuf, sizeof hashbuf, cookie);
	b64encode_urlsafe(cookie, cookie, 18);
	digest_close(digest);
	free(fingerprint);

	char filename[PATH_MAX], usedname[PATH_MAX];
	snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "%s", confbase, cookie);
	snprintf(usedname, sizeof usedname, "%s" SLASH "invitations" SLASH "%s.used", confbase, cookie);

	// Atomically rename the invitation file
	if(rename(filename, usedname)) {
		if(errno == ENOENT)
			logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s tried to use non-existing invitation %s\n", c->hostname, cookie);
		else
			logger(DEBUG_ALWAYS, LOG_ERR, "Error trying to rename invitation %s\n", cookie);
		return false;
	}

	// Open the renamed file
	FILE *f = fopen(usedname, "r");
	if(!f) {
		logger(DEBUG_ALWAYS, LOG_ERR, "Error trying to open invitation %s\n", cookie);
		return false;
	}

	// Read the new node's Name from the file
	char buf[1024];
	fgets(buf, sizeof buf, f);
	if(*buf)
		buf[strlen(buf) - 1] = 0;

	len = strcspn(buf, " \t=");
	char *name = buf + len;
	name += strspn(name, " \t");
	if(*name == '=') {
		name++;
		name += strspn(name, " \t");
	}
	buf[len] = 0;

	if(!*buf || !*name || strcasecmp(buf, "Name") || !check_id(name)) {
		logger(DEBUG_ALWAYS, LOG_ERR, "Invalid invitation file %s\n", cookie);
		fclose(f);
		return false;
	}

	free(c->name);
	c->name = xstrdup(name);

	// Send the node the contents of the invitation file
	rewind(f);
	size_t result;
	while((result = fread(buf, 1, sizeof buf, f)))
		sptps_send_record(&c->sptps, 0, buf, result);
	sptps_send_record(&c->sptps, 1, buf, 0);
	fclose(f);
	unlink(usedname);

	c->status.invitation_used = true;

	logger(DEBUG_CONNECTIONS, LOG_INFO, "Invitation %s succesfully sent to %s (%s)", cookie, c->name, c->hostname);
	return true;
}
Exemplo n.º 5
0
Arquivo: fsck.c Projeto: xentec/tinc
int fsck(const char *argv0) {
#ifdef HAVE_MINGW
	int uid = 0;
#else
	uid_t uid = getuid();
#endif

	// Check that tinc.conf is readable.

	if(access(tinc_conf, R_OK)) {
		fprintf(stderr, "ERROR: cannot read %s: %s\n", tinc_conf, strerror(errno));
		if(errno == ENOENT) {
			fprintf(stderr, "No tinc configuration found. Create a new one with:\n\n");
			print_tinc_cmd(argv0, "init");
		} else if(errno == EACCES) {
			if(uid != 0)
				fprintf(stderr, "You are currently not running tinc as root. Use sudo?\n");
			else
				fprintf(stderr, "Check the permissions of each component of the path %s.\n", tinc_conf);
		}
		return 1;
	}

	char *name = get_my_name(true);
	if(!name) {
		fprintf(stderr, "ERROR: tinc cannot run without a valid Name.\n");
		return 1;
	}

	// Check for private keys.
	// TODO: use RSAPrivateKeyFile and Ed25519PrivateKeyFile variables if present.

	struct stat st;
	char fname[PATH_MAX];
	char dname[PATH_MAX];

	ecdsa_t *ecdsa_priv = NULL;
	snprintf(fname, sizeof fname, "%s/ed25519_key.priv", confbase);

	if(stat(fname, &st)) {
		if(errno != ENOENT) {
			// Something is seriously wrong here. If we can access the directory with tinc.conf in it, we should certainly be able to stat() an existing file.
			fprintf(stderr, "ERROR: cannot read %s: %s\n", fname, strerror(errno));
			fprintf(stderr, "Please correct this error.\n");
			return 1;
		}
	} else {
		FILE *f = fopen(fname, "r");
		if(!f) {
			fprintf(stderr, "ERROR: could not open %s: %s\n", fname, strerror(errno));
			return 1;
		}
		ecdsa_priv = ecdsa_read_pem_private_key(f);
		fclose(f);
		if(!ecdsa_priv) {
			fprintf(stderr, "ERROR: No key or unusable key found in %s.\n", fname);
			fprintf(stderr, "You can generate a new Ed25519 key with:\n\n");
			print_tinc_cmd(argv0, "generate-ed25519-keys");
			return 1;
		}

		if(st.st_mode & 077) {
			fprintf(stderr, "WARNING: unsafe file permissions on %s.\n", fname);
			if(st.st_uid != uid) {
				fprintf(stderr, "You are not running %s as the same uid as %s.\n", argv0, fname);
			} else if(ask_fix()) {
				if(chmod(fname, st.st_mode & ~077))
					fprintf(stderr, "ERROR: could not change permissions of %s: %s\n", fname, strerror(errno));
				else
					fprintf(stderr, "Fixed permissions of %s.\n", fname);
			}
		}
	}

	if(!ecdsa_priv) {
		fprintf(stderr, "ERROR: No Ed25519 private key found.\n");
		fprintf(stderr, "You can generate new keys with:\n\n");
		print_tinc_cmd(argv0, "generate-keys");
		return 1;
	}

	// Check for public keys.
	// TODO: use RSAPublicKeyFile and Ed25519PublicKeyFile variables if present.

	snprintf(fname, sizeof fname, "%s/hosts/%s", confbase, name);
	if(access(fname, R_OK))
		fprintf(stderr, "WARNING: cannot read %s\n", fname);

	FILE *f;


	// TODO: this should read the Ed25519PublicKey config variable instead.
	ecdsa_t *ecdsa_pub = NULL;

	f = fopen(fname, "r");
	if(f)
		ecdsa_pub = ecdsa_read_pem_public_key(f);
	fclose(f);

	if(ecdsa_priv) {
		if(!ecdsa_pub) {
			fprintf(stderr, "WARNING: No (usable) public Ed25519 key found.\n");
			if(ask_fix()) {
				FILE *f = fopen(fname, "a");
				if(f) {
					if(ecdsa_write_pem_public_key(ecdsa_priv, f))
						fprintf(stderr, "Wrote Ed25519 public key to %s.\n", fname);
					else
						fprintf(stderr, "ERROR: could not write Ed25519 public key to %s.\n", fname);
					fclose(f);
				} else {
					fprintf(stderr, "ERROR: could not append to %s: %s\n", fname, strerror(errno));
				}
			}
		} else {
			// TODO: suggest remedies
			char *key1 = ecdsa_get_base64_public_key(ecdsa_pub);
			if(!key1) {
				fprintf(stderr, "ERROR: public Ed25519 key does not work.\n");
				return 1;
			}
			char *key2 = ecdsa_get_base64_public_key(ecdsa_priv);
			if(!key2) {
				free(key1);
				fprintf(stderr, "ERROR: private Ed25519 key does not work.\n");
				return 1;
			}
			int result = strcmp(key1, key2);
			free(key1);
			free(key2);
			if(result) {
				fprintf(stderr, "ERROR: public and private Ed25519 keys do not match.\n");
				return 1;
			}
		}
	} else {
		if(ecdsa_pub)
			fprintf(stderr, "WARNING: A public Ed25519 key was found but no private key is known.\n");
	}

	// Check whether scripts are executable

	struct dirent *ent;
	DIR *dir = opendir(confbase);
	if(!dir) {
		fprintf(stderr, "ERROR: cannot read directory %s: %s\n", confbase, strerror(errno));
		return 1;
	}

	while((ent = readdir(dir))) {
		if(strtailcmp(ent->d_name, "-up") && strtailcmp(ent->d_name, "-down"))
			continue;

		strncpy(fname, ent->d_name, sizeof fname);
		char *dash = strrchr(fname, '-');
		if(!dash)
			continue;
		*dash = 0;

		if(strcmp(fname, "tinc") && strcmp(fname, "host") && strcmp(fname, "subnet")) {
			static bool explained = false;
			fprintf(stderr, "WARNING: Unknown script %s" SLASH "%s found.\n", confbase, ent->d_name);
			if(!explained) {
				fprintf(stderr, "The only scripts in %s executed by tinc are:\n", confbase);
				fprintf(stderr, "tinc-up, tinc-down, host-up, host-down, subnet-up and subnet-down.\n");
				explained = true;
			}
			continue;
		}

		snprintf(fname, sizeof fname, "%s" SLASH "%s", confbase, ent->d_name);
		if(access(fname, R_OK | X_OK)) {
			if(errno != EACCES) {
				fprintf(stderr, "ERROR: cannot access %s: %s\n", fname, strerror(errno));
				continue;
			}
			fprintf(stderr, "WARNING: cannot read and execute %s: %s\n", fname, strerror(errno));
			if(ask_fix()) {
				if(chmod(fname, 0755))
					fprintf(stderr, "ERROR: cannot change permissions on %s: %s\n", fname, strerror(errno));
			}
		}
	}
	closedir(dir);

	snprintf(dname, sizeof dname, "%s" SLASH "hosts", confbase);
	dir = opendir(dname);
	if(!dir) {
		fprintf(stderr, "ERROR: cannot read directory %s: %s\n", dname, strerror(errno));
		return 1;
	}

	while((ent = readdir(dir))) {
		if(strtailcmp(ent->d_name, "-up") && strtailcmp(ent->d_name, "-down"))
			continue;

		strncpy(fname, ent->d_name, sizeof fname);
		char *dash = strrchr(fname, '-');
		if(!dash)
			continue;
		*dash = 0;

		snprintf(fname, sizeof fname, "%s" SLASH "hosts" SLASH "%s", confbase, ent->d_name);
		if(access(fname, R_OK | X_OK)) {
			if(errno != EACCES) {
				fprintf(stderr, "ERROR: cannot access %s: %s\n", fname, strerror(errno));
				continue;
			}
			fprintf(stderr, "WARNING: cannot read and execute %s: %s\n", fname, strerror(errno));
			if(ask_fix()) {
				if(chmod(fname, 0755))
					fprintf(stderr, "ERROR: cannot change permissions on %s: %s\n", fname, strerror(errno));
			}
		}
	}
	closedir(dir);
	
	// Check for obsolete / unsafe / unknown configuration variables.

	check_conffile(tinc_conf, true);

	dir = opendir(dname);
	if(dir) {
		while((ent = readdir(dir))) {
			if(!check_id(ent->d_name))
				continue;

			snprintf(fname, sizeof fname, "%s" SLASH "hosts" SLASH "%s", confbase, ent->d_name);
			check_conffile(fname, false);
		}
		closedir(dir);
	}

	return 0;
}
Exemplo n.º 6
0
int cmd_join(int argc, char *argv[]) {
	free(data);
	data = NULL;
	datalen = 0;

	if(argc > 2) {
		fprintf(stderr, "Too many arguments!\n");
		return 1;
	}

	// Make sure confbase exists and is accessible.
	if(!confbase_given && mkdir(confdir, 0755) && errno != EEXIST) {
		fprintf(stderr, "Could not create directory %s: %s\n", confdir, strerror(errno));
		return 1;
	}

	if(mkdir(confbase, 0777) && errno != EEXIST) {
		fprintf(stderr, "Could not create directory %s: %s\n", confbase, strerror(errno));
		return 1;
	}

	if(access(confbase, R_OK | W_OK | X_OK)) {
		fprintf(stderr, "No permission to write in directory %s: %s\n", confbase, strerror(errno));
		return 1;
	}

	// If a netname or explicit configuration directory is specified, check for an existing tinc.conf.
	if((netname || confbasegiven) && !access(tinc_conf, F_OK)) {
		fprintf(stderr, "Configuration file %s already exists!\n", tinc_conf);
		return 1;
	}

	// Either read the invitation from the command line or from stdin.
	char *invitation;

	if(argc > 1) {
		invitation = argv[1];
	} else {
		if(tty)
			fprintf(stderr, "Enter invitation URL: ");
		errno = EPIPE;
		if(!fgets(line, sizeof line, stdin)) {
			fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
			return false;
		}
		invitation = line;
	}

	// Parse the invitation URL.
	rstrip(line);

	char *slash = strchr(invitation, '/');
	if(!slash)
		goto invalid;

	*slash++ = 0;

	if(strlen(slash) != 48)
		goto invalid;

	char *address = invitation;
	char *port = NULL;
	if(*address == '[') {
		address++;
		char *bracket = strchr(address, ']');
		if(!bracket)
			goto invalid;
		*bracket = 0;
		if(bracket[1] == ':')
			port = bracket + 2;
	} else {
		port = strchr(address, ':');
		if(port)
			*port++ = 0;
	}

	if(!port || !*port)
		port = "655";

	if(!b64decode(slash, hash, 24) || !b64decode(slash + 24, cookie, 24))
		goto invalid;

	// Generate a throw-away key for the invitation.
	ecdsa_t *key = ecdsa_generate();
	if(!key)
		return 1;

	char *b64key = ecdsa_get_base64_public_key(key);

	// Connect to the tinc daemon mentioned in the URL.
	struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
	if(!ai)
		return 1;

	struct addrinfo *aip = NULL;

next:
	if(!aip)
		aip = ai;
	else {
		aip = aip->ai_next;
		if(!aip)
			return 1;
	}

	sock = socket(aip->ai_family, aip->ai_socktype, aip->ai_protocol);
	if(sock <= 0) {
		fprintf(stderr, "Could not open socket: %s\n", strerror(errno));
		goto next;
	}

	if(connect(sock, aip->ai_addr, aip->ai_addrlen)) {
		char *addrstr, *portstr;
		sockaddr2str((sockaddr_t *)aip->ai_addr, &addrstr, &portstr);
		fprintf(stderr, "Could not connect to %s port %s: %s\n", addrstr, portstr, strerror(errno));
		free(addrstr);
		free(portstr);
		closesocket(sock);
		goto next;
	}

	fprintf(stderr, "Connected to %s port %s...\n", address, port);

	// Tell him we have an invitation, and give him our throw-away key.
	int len = snprintf(line, sizeof line, "0 ?%s %d.%d\n", b64key, PROT_MAJOR, PROT_MINOR);
	if(len <= 0 || len >= sizeof line)
		abort();

	if(!sendline(sock, "0 ?%s %d.%d", b64key, PROT_MAJOR, 1)) {
		fprintf(stderr, "Error sending request to %s port %s: %s\n", address, port, strerror(errno));
		closesocket(sock);
		goto next;
	}

	char hisname[4096] = "";
	int code, hismajor, hisminor = 0;

	if(!recvline(sock, line, sizeof line) || sscanf(line, "%d %s %d.%d", &code, hisname, &hismajor, &hisminor) < 3 || code != 0 || hismajor != PROT_MAJOR || !check_id(hisname) || !recvline(sock, line, sizeof line) || !rstrip(line) || sscanf(line, "%d ", &code) != 1 || code != ACK || strlen(line) < 3) {
		fprintf(stderr, "Cannot read greeting from peer\n");
		closesocket(sock);
		goto next;
	}

	// Check if the hash of the key he gave us matches the hash in the URL.
	char *fingerprint = line + 2;
	char hishash[64];
	if(sha512(fingerprint, strlen(fingerprint), hishash)) {
		fprintf(stderr, "Could not create digest\n%s\n", line + 2);
		return 1;
	}
	if(memcmp(hishash, hash, 18)) {
		fprintf(stderr, "Peer has an invalid key!\n%s\n", line + 2);
		return 1;

	}
	
	ecdsa_t *hiskey = ecdsa_set_base64_public_key(fingerprint);
	if(!hiskey)
		return 1;

	// Start an SPTPS session
	if(!sptps_start(&sptps, NULL, true, false, key, hiskey, "tinc invitation", 15, invitation_send, invitation_receive))
		return 1;

	// Feed rest of input buffer to SPTPS
	if(!sptps_receive_data(&sptps, buffer, blen))
		return 1;

	while((len = recv(sock, line, sizeof line, 0))) {
		if(len < 0) {
			if(errno == EINTR)
				continue;
			fprintf(stderr, "Error reading data from %s port %s: %s\n", address, port, strerror(errno));
			return 1;
		}

		char *p = line;
		while(len) {
			int done = sptps_receive_data(&sptps, p, len);
			if(!done)
				return 1;
			len -= done;
			p += done;
		}
	}
	
	sptps_stop(&sptps);
	ecdsa_free(hiskey);
	ecdsa_free(key);
	closesocket(sock);

	if(!success) {
		fprintf(stderr, "Connection closed by peer, invitation cancelled.\n");
		return 1;
	}

	return 0;

invalid:
	fprintf(stderr, "Invalid invitation URL.\n");
	return 1;
}
Exemplo n.º 7
0
static bool finalize_join(void) {
	char *name = xstrdup(get_value(data, "Name"));
	if(!name) {
		fprintf(stderr, "No Name found in invitation!\n");
		return false;
	}

	if(!check_id(name)) {
		fprintf(stderr, "Invalid Name found in invitation: %s!\n", name);
		return false;
	}

	if(!netname)
		netname = grep(data, "NetName");

	bool ask_netname = false;
	char temp_netname[32];

make_names:
	if(!confbasegiven) {
		free(confbase);
		confbase = NULL;
	}

	make_names(false);

	free(tinc_conf);
	free(hosts_dir);

	xasprintf(&tinc_conf, "%s" SLASH "tinc.conf", confbase);
	xasprintf(&hosts_dir, "%s" SLASH "hosts", confbase);

	if(!access(tinc_conf, F_OK)) {
		fprintf(stderr, "Configuration file %s already exists!\n", tinc_conf);
		if(confbasegiven)
			return false;

		// Generate a random netname, ask for a better one later.
		ask_netname = true;
		snprintf(temp_netname, sizeof temp_netname, "join_%x", rand());
		netname = temp_netname;
		goto make_names;
	}	

	if(mkdir(confbase, 0777) && errno != EEXIST) {
		fprintf(stderr, "Could not create directory %s: %s\n", confbase, strerror(errno));
		return false;
	}

	if(mkdir(hosts_dir, 0777) && errno != EEXIST) {
		fprintf(stderr, "Could not create directory %s: %s\n", hosts_dir, strerror(errno));
		return false;
	}

	FILE *f = fopen(tinc_conf, "w");
	if(!f) {
		fprintf(stderr, "Could not create file %s: %s\n", tinc_conf, strerror(errno));
		return false;
	}

	fprintf(f, "Name = %s\n", name);

	char filename[PATH_MAX];
	snprintf(filename, sizeof filename, "%s" SLASH "%s", hosts_dir, name);
	FILE *fh = fopen(filename, "w");
	if(!fh) {
		fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
		fclose(f);
		return false;
	}

	// Filter first chunk on approved keywords, split between tinc.conf and hosts/Name
	// Other chunks go unfiltered to their respective host config files
	const char *p = data;
	char *l, *value;

	while((l = get_line(&p))) {
		// Ignore comments
		if(*l == '#')
			continue;

		// Split line into variable and value
		int len = strcspn(l, "\t =");
		value = l + len;
		value += strspn(value, "\t ");
		if(*value == '=') {
			value++;
			value += strspn(value, "\t ");
		}
		l[len] = 0;

		// Is it a Name?
		if(!strcasecmp(l, "Name"))
			if(strcmp(value, name))
				break;
			else
				continue;
		else if(!strcasecmp(l, "NetName"))
			continue;

		// Check the list of known variables
		bool found = false;
		int i;
		for(i = 0; variables[i].name; i++) {
			if(strcasecmp(l, variables[i].name))
				continue;
			found = true;
			break;
		}

		// Ignore unknown and unsafe variables
		if(!found) {
			fprintf(stderr, "Ignoring unknown variable '%s' in invitation.\n", l);
			continue;
		} else if(!(variables[i].type & VAR_SAFE)) {
			fprintf(stderr, "Ignoring unsafe variable '%s' in invitation.\n", l);
			continue;
		}

		// Copy the safe variable to the right config file
		fprintf(variables[i].type & VAR_HOST ? fh : f, "%s = %s\n", l, value);
	}

	fclose(f);

	while(l && !strcasecmp(l, "Name")) {
		if(!check_id(value)) {
			fprintf(stderr, "Invalid Name found in invitation.\n");
			return false;
		}

		if(!strcmp(value, name)) {
			fprintf(stderr, "Secondary chunk would overwrite our own host config file.\n");
			return false;
		}

		snprintf(filename, sizeof filename, "%s" SLASH "%s", hosts_dir, value);
		f = fopen(filename, "w");

		if(!f) {
			fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
			return false;
		}

		while((l = get_line(&p))) {
			if(!strcmp(l, "#---------------------------------------------------------------#"))
				continue;
			int len = strcspn(l, "\t =");
			if(len == 4 && !strncasecmp(l, "Name", 4)) {
				value = l + len;
				value += strspn(value, "\t ");
				if(*value == '=') {
					value++;
					value += strspn(value, "\t ");
				}
				l[len] = 0;
				break;
			}

			fputs(l, f);
			fputc('\n', f);
		}

		fclose(f);
	}

	// Generate our key and send a copy to the server
	ecdsa_t *key = ecdsa_generate();
	if(!key)
		return false;

	char *b64key = ecdsa_get_base64_public_key(key);
	if(!b64key)
		return false;

	snprintf(filename, sizeof filename, "%s" SLASH "ed25519_key.priv", confbase);
	f = fopenmask(filename, "w", 0600);
	if(!f)
		return false;

	if(!ecdsa_write_pem_private_key(key, f)) {
		fprintf(stderr, "Error writing private key!\n");
		ecdsa_free(key);
		fclose(f);
		return false;
	}

	fclose(f);

	fprintf(fh, "Ed25519PublicKey = %s\n", b64key);

	sptps_send_record(&sptps, 1, b64key, strlen(b64key));
	free(b64key);
	ecdsa_free(key);

	check_port(name);

ask_netname:
	if(ask_netname && tty) {
		fprintf(stderr, "Enter a new netname: ");
		if(!fgets(line, sizeof line, stdin)) {
			fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
			return false;
		}
		if(!*line || *line == '\n')
			goto ask_netname;

		line[strlen(line) - 1] = 0;

		char newbase[PATH_MAX];
		snprintf(newbase, sizeof newbase, CONFDIR SLASH "tinc" SLASH "%s", line);
		if(rename(confbase, newbase)) {
			fprintf(stderr, "Error trying to rename %s to %s: %s\n", confbase, newbase, strerror(errno));
			goto ask_netname;
		}

		netname = line;
		make_names(false);
	}

	fprintf(stderr, "Configuration stored in: %s\n", confbase);

	return true;
}
Exemplo n.º 8
0
int cmd_invite(int argc, char *argv[]) {
	if(argc < 2) {
		fprintf(stderr, "Not enough arguments!\n");
		return 1;
	}

	// Check validity of the new node's name
	if(!check_id(argv[1])) {
		fprintf(stderr, "Invalid name for node.\n");
		return 1;
	}

	char *myname = get_my_name(true);
	if(!myname)
		return 1;

	// Ensure no host configuration file with that name exists
	char filename[PATH_MAX];
	snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", confbase, argv[1]);
	if(!access(filename, F_OK)) {
		fprintf(stderr, "A host config file for %s already exists!\n", argv[1]);
		return 1;
	}

	// If a daemon is running, ensure no other nodes know about this name
	bool found = false;
	if(connect_tincd(false)) {
		sendline(fd, "%d %d", CONTROL, REQ_DUMP_NODES);

		while(recvline(fd, line, sizeof line)) {
			char node[4096];
			int code, req;
			if(sscanf(line, "%d %d %s", &code, &req, node) != 3)
				break;
			if(!strcmp(node, argv[1]))
				found = true;
		}

		if(found) {
			fprintf(stderr, "A node with name %s is already known!\n", argv[1]);
			return 1;
		}
	}

	snprintf(filename, sizeof filename, "%s" SLASH "invitations", confbase);
	if(mkdir(filename, 0700) && errno != EEXIST) {
		fprintf(stderr, "Could not create directory %s: %s\n", filename, strerror(errno));
		return 1;
	}

	// Count the number of valid invitations, clean up old ones
	DIR *dir = opendir(filename);
	if(!dir) {
		fprintf(stderr, "Could not read directory %s: %s\n", filename, strerror(errno));
		return 1;
	}

	errno = 0;
	int count = 0;
	struct dirent *ent;
	time_t deadline = time(NULL) - 604800; // 1 week in the past

	while((ent = readdir(dir))) {
		if(strlen(ent->d_name) != 24)
			continue;
		char invname[PATH_MAX];
		struct stat st;
		snprintf(invname, sizeof invname, "%s" SLASH "%s", filename, ent->d_name);
		if(!stat(invname, &st)) {
			if(deadline < st.st_mtime)
				count++;
			else
				unlink(invname);
		} else {
			fprintf(stderr, "Could not stat %s: %s\n", invname, strerror(errno));
			errno = 0;
		}
	}

	closedir(dir);

	if(errno) {
		fprintf(stderr, "Error while reading directory %s: %s\n", filename, strerror(errno));
		return 1;
	}
		
	ecdsa_t *key;
	snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "ed25519_key.priv", confbase);

	// Remove the key if there are no outstanding invitations.
	if(!count)
		unlink(filename);

	// Create a new key if necessary.
	FILE *f = fopen(filename, "r");
	if(!f) {
		if(errno != ENOENT) {
			fprintf(stderr, "Could not read %s: %s\n", filename, strerror(errno));
			return 1;
		}

		key = ecdsa_generate();
		if(!key)
			return 1;
		f = fopen(filename, "w");
		if(!f) {
			fprintf(stderr, "Could not write %s: %s\n", filename, strerror(errno));
			return 1;
		}
		chmod(filename, 0600);
		if(!ecdsa_write_pem_private_key(key, f)) {
			fprintf(stderr, "Could not write ECDSA private key\n");
			fclose(f);
			return 1;
		}
		fclose(f);

		if(connect_tincd(false))
			sendline(fd, "%d %d", CONTROL, REQ_RELOAD);
	} else {
		key = ecdsa_read_pem_private_key(f);
		fclose(f);
		if(!key)
			fprintf(stderr, "Could not read private key from %s\n", filename);
	}

	if(!key)
		return 1;

	// Create a hash of the key.
	char hash[64];
	char *fingerprint = ecdsa_get_base64_public_key(key);
	sha512(fingerprint, strlen(fingerprint), hash);
	b64encode_urlsafe(hash, hash, 18);

	// Create a random cookie for this invitation.
	char cookie[25];
	randomize(cookie, 18);

	// Create a filename that doesn't reveal the cookie itself
	char buf[18 + strlen(fingerprint)];
	char cookiehash[64];
	memcpy(buf, cookie, 18);
	memcpy(buf + 18, fingerprint, sizeof buf - 18);
	sha512(buf, sizeof buf, cookiehash);
	b64encode_urlsafe(cookiehash, cookiehash, 18);

	b64encode_urlsafe(cookie, cookie, 18);

	// Create a file containing the details of the invitation.
	snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "%s", confbase, cookiehash);
	int ifd = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
	if(!ifd) {
		fprintf(stderr, "Could not create invitation file %s: %s\n", filename, strerror(errno));
		return 1;
	}
	f = fdopen(ifd, "w");
	if(!f)
		abort();

	// Get the local address
	char *address = get_my_hostname();

	// Fill in the details.
	fprintf(f, "Name = %s\n", argv[1]);
	if(netname)
		fprintf(f, "NetName = %s\n", netname);
	fprintf(f, "ConnectTo = %s\n", myname);

	// Copy Broadcast and Mode
	FILE *tc = fopen(tinc_conf, "r");
	if(tc) {
		char buf[1024];
		while(fgets(buf, sizeof buf, tc)) {
			if((!strncasecmp(buf, "Mode", 4) && strchr(" \t=", buf[4]))
					|| (!strncasecmp(buf, "Broadcast", 9) && strchr(" \t=", buf[9]))) {
				fputs(buf, f);
				// Make sure there is a newline character.
				if(!strchr(buf, '\n'))
					fputc('\n', f);
			}
		}
		fclose(tc);
	}

	fprintf(f, "#---------------------------------------------------------------#\n");
	fprintf(f, "Name = %s\n", myname);

	char filename2[PATH_MAX];
	snprintf(filename2, sizeof filename2, "%s" SLASH "hosts" SLASH "%s", confbase, myname);
	fcopy(f, filename2);
	fclose(f);

	// Create an URL from the local address, key hash and cookie
	char *url;
	xasprintf(&url, "%s/%s%s", address, hash, cookie);

	// Call the inviation-created script
	char *envp[6] = {};
	xasprintf(&envp[0], "NAME=%s", myname);
	xasprintf(&envp[1], "NETNAME=%s", netname);
	xasprintf(&envp[2], "NODE=%s", argv[1]);
	xasprintf(&envp[3], "INVITATION_FILE=%s", filename);
	xasprintf(&envp[4], "INVITATION_URL=%s", url);
	execute_script("invitation-created", envp);
	for(int i = 0; i < 6 && envp[i]; i++)
		free(envp[i]);

	puts(url);
	free(url);
	free(address);

	return 0;
}