Merge pull request #688 from nurupo/dht_bootstrap_daemon

Improved DHT bootstrap daemon

1 files changed, 459 insertions, 0 deletions

diff --git a/other/bootstrap_serverdaemon/tox_dht_bootstrap_server_daemon.c b/other/bootstrap_serverdaemon/tox_dht_bootstrap_server_daemon.c
new file mode 100644
index 00000000..134346a1
--- /dev/null
+++ b/other/bootstrap_serverdaemon/tox_dht_bootstrap_server_daemon.c
@@ -0,0 +1,459 @@
+/* tox_dht_bootstrap_server_daemon
+ *
+ * A simple DHT bootstrap server for tox - daemon edition.
+ *
+ *  Copyright (C) 2014 Tox project All Rights Reserved.
+ *
+ *  This file is part of Tox.
+ *
+ *  Tox is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Tox is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with Tox.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <syslog.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <libconfig.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "../../toxcore/DHT.h"
+#include "../../toxcore/friend_requests.h"
+#include "../../toxcore/LAN_discovery.h"
+
+#include "../../testing/misc_tools.c"
+
+#define DAEMON_NAME "tox_dht_bootstrap_server_daemon"
+
+#define SLEEP_TIME_MILLISECONDS 30
+#define sleep usleep(1000*SLEEP_TIME_MILLISECONDS)
+
+#define DEFAULT_PID_FILE_PATH        ".tox_dht_bootstrap_server_daemon.pid"
+#define DEFAULT_KEYS_FILE_PATH       ".tox_dht_bootstrap_server_daemon.keys"
+#define DEFAULT_PORT                 33445
+#define DEFAULT_ENABLE_IPV6          0 // 1 - true, 0 - false
+#define DEFAULT_ENABLE_LAN_DISCOVERY 1 // 1 - true, 0 - false
+
+
+// Uses the already existing key or creates one if it didn't exist
+//
+// retirns 1 on success
+//         0 on failure - no keys were read or stored
+
+int manage_keys(DHT *dht, char *keys_file_path)
+{
+    const uint32_t KEYS_SIZE = crypto_box_PUBLICKEYBYTES + crypto_box_SECRETKEYBYTES;
+    uint8_t keys[KEYS_SIZE];
+    FILE *keys_file;
+
+    // Check if file exits, proceed to open and load keys
+    keys_file = fopen(keys_file_path, "r");
+
+    if (keys_file != NULL) {
+        size_t read_size = fread(keys, sizeof(uint8_t), KEYS_SIZE, keys_file);
+
+        if (read_size != KEYS_SIZE) {
+            return 0;
+        }
+
+        load_keys(dht->c, keys);
+    } else {
+        // Otherwise save new keys
+        new_keys(dht->c);
+        save_keys(dht->c, keys);
+
+        keys_file = fopen(keys_file_path, "w");
+
+        size_t write_size = fwrite(keys, sizeof(uint8_t), KEYS_SIZE, keys_file);
+
+        if (write_size != KEYS_SIZE) {
+            return 0;
+        }
+    }
+
+    fclose(keys_file);
+
+    return 1;
+}
+
+// Gets general config options
+//
+// Important: you are responsible for freeing `pid_file_path` and `keys_file_path`
+//
+// returns 1 on success
+//         0 on failure, doesn't modify any data pointed by arguments
+
+int get_general_config(char *cfg_file_path, char **pid_file_path, char **keys_file_path, int *port, int *enable_ipv6,
+                       int *enable_lan_discovery)
+{
+    config_t cfg;
+
+    const char *NAME_PORT                 = "port";
+    const char *NAME_PID_FILE_PATH        = "pid_file_path";
+    const char *NAME_KEYS_FILE_PATH       = "keys_file_path";
+    const char *NAME_ENABLE_IPV6          = "enable_ipv6";
+    const char *NAME_ENABLE_LAN_DISCOVERY = "enable_lan_discovery";
+
+    config_init(&cfg);
+
+    // Read the file. If there is an error, report it and exit.
+    if (config_read_file(&cfg, cfg_file_path) == CONFIG_FALSE) {
+        syslog(LOG_ERR, "%s:%d - %s\n", config_error_file(&cfg), config_error_line(&cfg), config_error_text(&cfg));
+        config_destroy(&cfg);
+        return 0;
+    }
+
+    // Get port
+    if (config_lookup_int(&cfg, NAME_PORT, port) == CONFIG_FALSE) {
+        syslog(LOG_WARNING, "No '%s' setting in configuration file.\n", NAME_PORT);
+        syslog(LOG_WARNING, "Using default '%s': %d\n", NAME_PORT, DEFAULT_PORT);
+        *port = DEFAULT_PORT;
+    }
+
+    // Get PID file location
+    const char *tmp_pid_file;
+
+    if (config_lookup_string(&cfg, NAME_PID_FILE_PATH, &tmp_pid_file) == CONFIG_FALSE) {
+        syslog(LOG_WARNING, "No '%s' setting in configuration file.\n", NAME_PID_FILE_PATH);
+        syslog(LOG_WARNING, "Using default '%s': %s\n", NAME_PID_FILE_PATH, DEFAULT_PID_FILE_PATH);
+        tmp_pid_file = DEFAULT_PID_FILE_PATH;
+    }
+
+    *pid_file_path = malloc(strlen(tmp_pid_file) + 1);
+    strcpy(*pid_file_path, tmp_pid_file);
+
+    // Get keys file location
+    const char *tmp_keys_file;
+
+    if (config_lookup_string(&cfg, NAME_KEYS_FILE_PATH, &tmp_keys_file) == CONFIG_FALSE) {
+        syslog(LOG_WARNING, "No '%s' setting in configuration file.\n", NAME_KEYS_FILE_PATH);
+        syslog(LOG_WARNING, "Using default '%s': %s\n", NAME_KEYS_FILE_PATH, DEFAULT_KEYS_FILE_PATH);
+        tmp_keys_file = DEFAULT_KEYS_FILE_PATH;
+    }
+
+    *keys_file_path = malloc(strlen(tmp_keys_file) + 1);
+    strcpy(*keys_file_path, tmp_keys_file);
+
+    // Get IPv6 option
+    if (config_lookup_bool(&cfg, NAME_ENABLE_IPV6, enable_ipv6) == CONFIG_FALSE) {
+        syslog(LOG_WARNING, "No '%s' setting in configuration file.\n", NAME_ENABLE_IPV6);
+        syslog(LOG_WARNING, "Using default '%s': %s\n", NAME_ENABLE_IPV6, DEFAULT_ENABLE_IPV6 ? "true" : "false");
+        *enable_ipv6 = DEFAULT_ENABLE_IPV6;
+    }
+
+    // Get LAN discovery option
+    if (config_lookup_bool(&cfg, NAME_ENABLE_LAN_DISCOVERY, enable_lan_discovery) == CONFIG_FALSE) {
+        syslog(LOG_WARNING, "No '%s' setting in configuration file.\n", NAME_ENABLE_LAN_DISCOVERY);
+        syslog(LOG_WARNING, "Using default '%s': %s\n", NAME_ENABLE_LAN_DISCOVERY,
+               DEFAULT_ENABLE_LAN_DISCOVERY ? "true" : "false");
+        *enable_lan_discovery = DEFAULT_ENABLE_LAN_DISCOVERY;
+    }
+
+    config_destroy(&cfg);
+
+    syslog(LOG_DEBUG, "Successfully read:\n");
+    syslog(LOG_DEBUG, "'%s': %s\n", NAME_PID_FILE_PATH,        *pid_file_path);
+    syslog(LOG_DEBUG, "'%s': %s\n", NAME_KEYS_FILE_PATH,       *keys_file_path);
+    syslog(LOG_DEBUG, "'%s': %d\n", NAME_PORT,                 *port);
+    syslog(LOG_DEBUG, "'%s': %s\n", NAME_ENABLE_IPV6,          *enable_ipv6          ? "true" : "false");
+    syslog(LOG_DEBUG, "'%s': %s\n", NAME_ENABLE_LAN_DISCOVERY, *enable_lan_discovery ? "true" : "false");
+
+    return 1;
+}
+
+// Bootstraps servers listed in the config file
+//
+// returns 1 on success
+//         0 on failure, either no or only some servers were bootstrapped
+
+int bootstrap_from_config(char *cfg_file_path, DHT *dht, int enable_ipv6)
+{
+    const char *NAME_BOOTSTRAP_SERVERS = "bootstrap_servers";
+
+    const char *NAME_PUBLIC_KEY = "public_key";
+    const char *NAME_PORT       = "port";
+    const char *NAME_ADDRESS    = "address";
+
+    config_t cfg;
+
+    config_init(&cfg);
+
+    if (config_read_file(&cfg, cfg_file_path) == CONFIG_FALSE) {
+        syslog(LOG_ERR, "%s:%d - %s\n", config_error_file(&cfg), config_error_line(&cfg), config_error_text(&cfg));
+        config_destroy(&cfg);
+        return 0;
+    }
+
+    config_setting_t *server_list = config_lookup(&cfg, NAME_BOOTSTRAP_SERVERS);
+
+    if (server_list == NULL) {
+        syslog(LOG_ERR, "No '%s' setting in configuration file.\n", NAME_BOOTSTRAP_SERVERS);
+        config_destroy(&cfg);
+        return 0;
+    }
+
+    int bs_port;
+    const char *bs_address;
+    const char *bs_public_key;
+
+    config_setting_t *server;
+
+    int i = 0;
+
+    while (config_setting_length(server_list)) {
+
+        server = config_setting_get_elem(server_list, 0);
+
+        if (server == NULL) {
+            return 0;
+        }
+
+        // Proceed only if all parts are present
+        if (config_setting_lookup_string(server, NAME_PUBLIC_KEY,  &bs_public_key) == CONFIG_FALSE ||
+                config_setting_lookup_int   (server, NAME_PORT,    &bs_port)       == CONFIG_FALSE ||
+                config_setting_lookup_string(server, NAME_ADDRESS, &bs_address)    == CONFIG_FALSE   ) {
+            goto next;
+        }
+
+        if (strlen(bs_public_key) != 64) {
+            syslog(LOG_WARNING, "bootstrap_server #%d: Invalid '%s': %s.\n", i, NAME_PUBLIC_KEY, bs_public_key);
+            goto next;
+        }
+
+        // not (1 <= port <= 65535)
+        if (bs_port < 1 || bs_port > 65535) {
+            syslog(LOG_WARNING, "bootstrap_server #%d: Invalid '%s': %d.\n", i, NAME_PORT, bs_port);
+            goto next;
+        }
+
+        const int address_resolved = DHT_bootstrap_from_address(dht, bs_address, enable_ipv6, htons(bs_port),
+                                     hex_string_to_bin((char *)bs_public_key));
+
+        if (!address_resolved) {
+            syslog(LOG_WARNING, "bootstrap_server #%d: Invalid '%s': %s.\n", i, NAME_ADDRESS, bs_address);
+            goto next;
+        }
+
+        syslog(LOG_DEBUG, "Successfully connected to %s:%d %s\n", bs_address, bs_port, bs_public_key);
+
+next:
+        // config_setting_lookup_string() allocates string inside and doesn't allow us to free it
+        // so in order to reuse `bs_public_key` and `bs_address` we have to remove the element
+        // which will cause libconfig to free allocated strings
+        config_setting_remove_elem(server_list, 0);
+        i++;
+    }
+
+    config_destroy(&cfg);
+
+    return 1;
+}
+
+// Checks if we are connected to the DHT
+//
+// returns 1 on success
+//         0 on failure
+
+int is_conencted(DHT *dht, int port, int enable_lan_discovery)
+{
+    uint16_t htons_port = htons(port);
+
+    int i;
+
+    for (i = 0; i < 100; i ++) {
+        do_DHT(dht);
+
+        if (enable_lan_discovery) {
+            send_LANdiscovery(htons_port, dht->c);
+        }
+
+        networking_poll(dht->c->lossless_udp->net);
+
+        if (DHT_isconnected(dht)) {
+            return 1;
+        }
+
+        sleep;
+    }
+
+    return 0;
+}
+
+// Prints public key
+
+void print_public_key(uint8_t *public_key)
+{
+    char buffer[64 + 1];
+    int index = 0;
+
+    int i;
+
+    for (i = 0; i < 32; i++) {
+        if (public_key[i] < 16) {
+            index += sprintf(buffer + index, "0");
+        }
+
+        index += sprintf(buffer + index, "%hhX", public_key[i]);
+    }
+
+    syslog(LOG_INFO, "Public Key: %s\n", buffer);
+
+    return;
+}
+
+int main(int argc, char *argv[])
+{
+    openlog(DAEMON_NAME, LOG_NOWAIT | LOG_PID, LOG_DAEMON);
+
+    if (argc < 2) {
+        syslog(LOG_ERR, "Please specify a configuration file. Exiting.\n");
+        return 1;
+    }
+
+    char *cfg_file_path = argv[1];
+    char *pid_file_path, *keys_file_path;
+    int port;
+    int enable_ipv6;
+    int enable_lan_discovery;
+
+    if (get_general_config(cfg_file_path, &pid_file_path, &keys_file_path, &port, &enable_ipv6, &enable_lan_discovery)) {
+        syslog(LOG_DEBUG, "General config read successfully\n");
+    } else {
+        syslog(LOG_ERR, "Couldn't read config file: %s. Exiting.\n", cfg_file_path);
+        return 1;
+    }
+
+    // not (1 <= port <= 65535)
+    if (port < 1 || port > 65535) {
+        syslog(LOG_ERR, "Invalid port: %d, must be 1 <= port <= 65535. Exiting.\n", port);
+        return 1;
+    }
+
+    // Check if the PID file exists
+    if (fopen(pid_file_path, "r")) {
+        syslog(LOG_ERR, "Another instance of the daemon is already running, PID file %s exists. Exiting.\n", pid_file_path);
+        return 1;
+    }
+
+    IP ip;
+    ip_init(&ip, enable_ipv6);
+
+    DHT *dht = new_DHT(new_net_crypto(new_networking(ip, port)));
+
+    if (dht == NULL) {
+        syslog(LOG_ERR, "Couldn't initialize Tox DHT instance. Exiting.\n");
+        return 1;
+    }
+
+    if (enable_lan_discovery) {
+        LANdiscovery_init(dht);
+    }
+
+    if (manage_keys(dht, keys_file_path)) {
+        syslog(LOG_DEBUG, "Keys are managed successfully\n");
+    } else {
+        syslog(LOG_ERR, "Couldn't read/write: %s. Exiting.\n", keys_file_path);
+        return 1;
+    }
+
+    if (bootstrap_from_config(cfg_file_path, dht, enable_ipv6)) {
+        syslog(LOG_DEBUG, "List of bootstrap servers read successfully\n");
+    } else {
+        syslog(LOG_ERR, "Couldn't read list of bootstrap servers in %s. Exiting.\n", cfg_file_path);
+        return 1;
+    }
+
+    if (is_conencted(dht, port, enable_lan_discovery)) {
+        syslog(LOG_INFO, "Successfully connected to DHT\n");
+    } else {
+        syslog(LOG_ERR, "Couldn't connect to the DHT. Check settings and network connections. Exiting.\n");
+        return 1;
+    }
+
+    print_public_key(dht->c->self_public_key);
+
+    // Write the PID file
+    FILE *pidf = fopen(pid_file_path, "w");
+
+    if (pidf == NULL) {
+        syslog(LOG_ERR, "Can't open the PID file for writing: %s. Exiting.\n", pid_file_path);
+        return 1;
+    }
+
+    free(pid_file_path);
+    free(keys_file_path);
+
+    // Fork off from the parent process
+    pid_t pid = fork();
+
+    if (pid < 0) {
+        syslog(LOG_ERR, "Forking failed. Exiting.\n");
+        return 1;
+    }
+
+    if (pid > 0) {
+        syslog(LOG_DEBUG, "Forked successfully: PID: %d.\n", pid);
+
+        return 0;
+    }
+
+    // Change the file mode mask
+    umask(0);
+
+    fprintf(pidf, "%d\n", pid);
+    fclose(pidf);
+
+    // Create a new SID for the child process
+    if (setsid() < 0) {
+        syslog(LOG_ERR, "SID creation failure. Exiting.\n");
+        return 1;
+    }
+
+    // Change the current working directory
+    if ((chdir("/")) < 0) {
+        syslog(LOG_ERR, "Couldn't change working directory to '/'. Exiting.\n");
+        return 1;
+    }
+
+    // Go quiet
+    close(STDOUT_FILENO);
+    close(STDIN_FILENO);
+    close(STDERR_FILENO);
+
+    uint64_t last_LANdiscovery = 0;
+    uint16_t htons_port = htons(port);
+
+    while (1) {
+        do_DHT(dht);
+
+        if (enable_lan_discovery && is_timeout(last_LANdiscovery, LAN_DISCOVERY_INTERVAL)) {
+            send_LANdiscovery(htons_port, dht->c);
+            last_LANdiscovery = unix_time();
+        }
+
+        networking_poll(dht->c->lossless_udp->net);
+
+        sleep;
+    }
+
+    return 1;
+}