ubus.c

   1 /*
   2  * Copyright (C) 2014 John Crispin <blogic@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <sys/types.h>
  15 #include <arpa/inet.h>
  16
  17 #include <stdio.h>
  18
  19 #include <libubus.h>
  20 #include <libubox/avl.h>
  21 #include <libubox/uloop.h>
  22
  23 #include "ubus.h"
  24 #include "cache.h"
  25
  26 static struct ubus_auto_conn conn;
  27 static struct blob_buf b;
  28
  29 static int
  30 mdns_reload(struct ubus_context *ctx, struct ubus_object *obj,
  31                 struct ubus_request_data *req, const char *method,
  32                 struct blob_attr *msg)
  33 {
  34         return 0;
  35 }
  36
  37 static int
  38 mdns_scan(struct ubus_context *ctx, struct ubus_object *obj,
  39                 struct ubus_request_data *req, const char *method,
  40                 struct blob_attr *msg)
  41 {
  42         cache_scan();
  43         return 0;
  44 }
  45
  46 static void
  47 mdns_add_records(const char *name)
  48 {
  49         struct cache_record *r, *q = avl_find_element(&records, name, r, avl);
  50         char *txt;
  51         char buffer[MAX_NAME_LEN];
  52
  53         if (!q)
  54                 return;
  55
  56         do {
  57                 r = q;
  58                 switch (r->type) {
  59                 case TYPE_TXT:
  60                         if (r->txt && strlen(r->txt)) {
  61                                 txt = r->txt;
  62                                 do {
  63                                         blobmsg_add_string(&b, "txt", txt);
  64                                         txt = &txt[strlen(txt) + 1];
  65                                 } while (*txt);
  66                         }
  67                         break;
  68
  69                 case TYPE_SRV:
  70                         if (r->port)
  71                                 blobmsg_add_u32(&b, "port", r->port);
  72                         break;
  73
  74                 case TYPE_A:
  75                         if ((r->rdlength == 4) && inet_ntop(AF_INET, r->rdata, buffer, INET6_ADDRSTRLEN))
  76                                 blobmsg_add_string(&b, "ipv4", buffer);
  77                         break;
  78
  79                 case TYPE_AAAA:
  80                         if ((r->rdlength == 16) && inet_ntop(AF_INET6, r->rdata, buffer, INET6_ADDRSTRLEN))
  81                                 blobmsg_add_string(&b, "ipv6", buffer);
  82                         break;
  83                 }
  84                 q = avl_next_element(r, avl);
  85         } while (q && !strcmp(r->record, q->record));
  86 }
  87
  88 static int
  89 mdns_browse(struct ubus_context *ctx, struct ubus_object *obj,
  90                 struct ubus_request_data *req, const char *method,
  91                 struct blob_attr *msg)
  92 {
  93         struct cache_entry *s, *q;
  94         char buffer[MAX_NAME_LEN];
  95         void *c1 = NULL, *c2;
  96
  97         blob_buf_init(&b, 0);
  98         avl_for_each_element(&entries, s, avl) {
  99                 char *local;
 100                 if (*((char *) s->avl.key) != '_')
 101                         continue;
 102                 snprintf(buffer, MAX_NAME_LEN, s->avl.key);
 103                 local = strstr(buffer, ".local");
 104                 if (local)
 105                         *local = '\0';
 106                 if (!strcmp(buffer, "_tcp") || !strcmp(buffer, "_udp"))
 107                         continue;
 108
 109                 if (!c1) {
 110                         char *type = cache_lookup_name(buffer);
 111                         c1 = blobmsg_open_table(&b, buffer);
 112                         if (type)
 113                                 blobmsg_add_string(&b, ".desc", type);
 114                 }
 115                 snprintf(buffer, MAX_NAME_LEN, s->entry);
 116                 local = strstr(buffer, "._");
 117                 if (local)
 118                         *local = '\0';
 119                 c2 = blobmsg_open_table(&b, buffer);
 120                 strncat(buffer, ".local", MAX_NAME_LEN);
 121                 mdns_add_records(buffer);
 122                 mdns_add_records(s->entry);
 123                 blobmsg_close_table(&b, c2);
 124                 q = avl_next_element(s, avl);
 125                 if (!q || avl_is_last(&entries, &s->avl) || strcmp(s->avl.key, q->avl.key)) {
 126                         blobmsg_close_table(&b, c1);
 127                         c1 = NULL;
 128                 }
 129         }
 130         ubus_send_reply(ctx, req, b.head);
 131
 132         return UBUS_STATUS_OK;
 133 }
 134
 135 static int
 136 mdns_hosts(struct ubus_context *ctx, struct ubus_object *obj,
 137                 struct ubus_request_data *req, const char *method,
 138                 struct blob_attr *msg)
 139 {
 140         struct cache_entry *s;
 141         char buffer[MAX_NAME_LEN];
 142         void *c;
 143
 144         blob_buf_init(&b, 0);
 145         avl_for_each_element(&entries, s, avl) {
 146                 char *local;
 147                 if (*((char *) s->avl.key) == '_')
 148                         continue;
 149                 snprintf(buffer, MAX_NAME_LEN, s->entry);
 150                 local = strstr(buffer, "._");
 151                 if (local)
 152                         *local = '\0';
 153                 c = blobmsg_open_table(&b, buffer);
 154                 strncat(buffer, ".local", MAX_NAME_LEN);
 155                 mdns_add_records(buffer);
 156                 mdns_add_records(s->entry);
 157                 blobmsg_close_table(&b, c);
 158         }
 159         ubus_send_reply(ctx, req, b.head);
 160
 161         return UBUS_STATUS_OK;
 162 }
 163
 164 static const struct ubus_method mdns_methods[] = {
 165         UBUS_METHOD_NOARG("scan", mdns_scan),
 166         UBUS_METHOD_NOARG("browse", mdns_browse),
 167         UBUS_METHOD_NOARG("hosts", mdns_hosts),
 168         UBUS_METHOD_NOARG("reload", mdns_reload),
 169 };
 170
 171 static struct ubus_object_type mdns_object_type =
 172         UBUS_OBJECT_TYPE("mdns", mdns_methods);
 173
 174 static struct ubus_object mdns_object = {
 175         .name = "mdns",
 176         .type = &mdns_object_type,
 177         .methods = mdns_methods,
 178         .n_methods = ARRAY_SIZE(mdns_methods),
 179 };
 180
 181 static void
 182 ubus_connect_handler(struct ubus_context *ctx)
 183 {
 184         int ret;
 185
 186         ret = ubus_add_object(ctx, &mdns_object);
 187         if (ret)
 188                 fprintf(stderr, "Failed to add object: %s\n", ubus_strerror(ret));
 189 }
 190
 191 void
 192 ubus_startup(void)
 193 {
 194         conn.cb = ubus_connect_handler;
 195         ubus_auto_connect(&conn);
 196 }