main.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2022 Felix Fietkau <nbd@nbd.name>
   4  */
   5 #define _GNU_SOURCE
   6 #include <unistd.h>
   7 #include <arpa/inet.h>
   8 #include <libubox/uloop.h>
   9 #include <libubox/blobmsg_json.h>
  10 #include "unetd.h"
  11
  12 struct cmdline_network {
  13         struct cmdline_network *next;
  14         char *data;
  15 };
  16
  17 static struct cmdline_network *cmd_nets;
  18 static const char *hosts_file;
  19 const char *mssfix_path = UNETD_MSS_BPF_PATH;
  20 bool debug;
  21
  22 static void
  23 network_write_hosts(struct network *net, FILE *f)
  24 {
  25         struct network_host *host;
  26         char ip[INET6_ADDRSTRLEN];
  27
  28         if (!net->net_config.local_host)
  29                 return;
  30
  31         avl_for_each_element(&net->hosts, host, node) {
  32                 inet_ntop(AF_INET6, &host->peer.local_addr, ip, sizeof(ip));
  33                 fprintf(f, "%s\t%s\n", ip, network_host_name(host));
  34         }
  35 }
  36
  37 void unetd_write_hosts(void)
  38 {
  39         struct network *net;
  40         char *tmpfile = NULL;
  41         FILE *f;
  42         int fd;
  43
  44         if (!hosts_file)
  45                 return;
  46
  47         asprintf(&tmpfile, "%s.XXXXXXXX", hosts_file);
  48         fd = mkstemp(tmpfile);
  49         if (fd < 0) {
  50                 perror("mkstemp");
  51                 goto out;
  52         }
  53
  54         chmod(tmpfile, 0644);
  55         f = fdopen(fd, "w");
  56         if (!f) {
  57                 close(fd);
  58                 goto out;
  59         }
  60
  61         avl_for_each_element(&networks, net, node)
  62                 network_write_hosts(net, f);
  63
  64         fclose(f);
  65
  66         if (rename(tmpfile, hosts_file))
  67                 unlink(tmpfile);
  68
  69 out:
  70         free(tmpfile);
  71 }
  72
  73 static void add_networks(void)
  74 {
  75         struct cmdline_network *net;
  76         static struct blob_buf b;
  77         struct blob_attr *name;
  78
  79         for (net = cmd_nets; net; net = net->next) {
  80                 blob_buf_init(&b, 0);
  81                 if (!blobmsg_add_json_from_string(&b, net->data))
  82                         continue;
  83
  84                 blobmsg_parse(&network_policy[NETWORK_ATTR_NAME], 1, &name,
  85                               blobmsg_data(b.head), blobmsg_len(b.head));
  86                 if (!name)
  87                         continue;
  88
  89                 unetd_network_add(blobmsg_get_string(name), b.head);
  90         }
  91
  92         blob_buf_free(&b);
  93 }
  94
  95 int main(int argc, char **argv)
  96 {
  97         struct cmdline_network *net;
  98         int ch;
  99
 100         while ((ch = getopt(argc, argv, "dh:M:N:")) != -1) {
 101                 switch (ch) {
 102                 case 'd':
 103                         debug = true;
 104                         break;
 105                 case 'h':
 106                         hosts_file = optarg;
 107                         break;
 108                 case 'N':
 109                         net = calloc(1, sizeof(*net));
 110                         net->next = cmd_nets;
 111                         net->data = optarg;
 112                         cmd_nets = net;
 113                         break;
 114                 case 'M':
 115                         mssfix_path = optarg;
 116                         break;
 117                 }
 118         }
 119
 120         uloop_init();
 121         unetd_ubus_init();
 122         unetd_write_hosts();
 123         add_networks();
 124         uloop_run();
 125         network_free_all();
 126         uloop_done();
 127
 128         return 0;
 129 }