ubusd_monitor.c

   1 /*
   2  * Copyright (C) 2015 Felix Fietkau <nbd@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 "ubusd.h"
  15
  16 static struct ubus_object *monitor_obj;
  17 static LIST_HEAD(monitors);
  18
  19 struct ubus_monitor {
  20         struct list_head list;
  21         struct ubus_client *cl;
  22         uint32_t seq;
  23 };
  24
  25 static void
  26 ubusd_monitor_free(struct ubus_monitor *m)
  27 {
  28         list_del(&m->list);
  29         free(m);
  30 }
  31
  32 static void
  33 ubusd_monitor_connect(struct ubus_client *cl, struct ubus_msg_buf *ub)
  34 {
  35         struct ubus_monitor *m;
  36
  37         ubusd_monitor_disconnect(cl);
  38
  39         m = calloc(1, sizeof(*m));
  40         m->cl = cl;
  41         list_add(&m->list, &monitors);
  42 }
  43
  44 void
  45 ubusd_monitor_disconnect(struct ubus_client *cl)
  46 {
  47         struct ubus_monitor *m;
  48
  49         list_for_each_entry(m, &monitors, list) {
  50                 if (m->cl != cl)
  51                         continue;
  52
  53                 ubusd_monitor_free(m);
  54                 return;
  55         }
  56 }
  57
  58 void
  59 ubusd_monitor_message(struct ubus_client *cl, struct ubus_msg_buf *ub, bool send)
  60 {
  61         static struct blob_buf mb;
  62         struct ubus_monitor *m;
  63
  64         if (list_empty(&monitors))
  65                 return;
  66
  67         blob_buf_init(&mb, 0);
  68         blob_put_int32(&mb, UBUS_MONITOR_CLIENT, cl->id.id);
  69         blob_put_int32(&mb, UBUS_MONITOR_PEER, ub->hdr.peer);
  70         blob_put_int32(&mb, UBUS_MONITOR_SEQ, ub->hdr.seq);
  71         blob_put_int32(&mb, UBUS_MONITOR_TYPE, ub->hdr.type);
  72         blob_put_int8(&mb, UBUS_MONITOR_SEND, send);
  73         blob_put(&mb, UBUS_MONITOR_DATA, blob_data(ub->data), blob_len(ub->data));
  74
  75         list_for_each_entry(m, &monitors, list) {
  76                 ub = ubus_msg_new(mb.head, blob_raw_len(mb.head), true);
  77                 ub->hdr.type = UBUS_MSG_MONITOR;
  78                 ub->hdr.seq = ++m->seq;
  79                 ubus_msg_send(m->cl, ub, true);
  80         }
  81 }
  82
  83 static int
  84 ubusd_monitor_recv(struct ubus_client *cl, struct ubus_msg_buf *ub,
  85                    const char *method, struct blob_attr *msg)
  86 {
  87         /* Only root is allowed for now */
  88         if (cl->uid != 0 || cl->gid != 0)
  89                 return UBUS_STATUS_PERMISSION_DENIED;
  90
  91         if (!strcmp(method, "add")) {
  92                 ubusd_monitor_connect(cl, ub);
  93                 return 0;
  94         }
  95
  96         if (!strcmp(method, "remove")) {
  97                 ubusd_monitor_disconnect(cl);
  98                 return 0;
  99         }
 100
 101         return UBUS_STATUS_METHOD_NOT_FOUND;
 102 }
 103
 104 void
 105 ubusd_monitor_init(void)
 106 {
 107         monitor_obj = ubusd_create_object_internal(NULL, UBUS_SYSTEM_OBJECT_MONITOR);
 108         if (monitor_obj != NULL)
 109                 monitor_obj->recv_msg = ubusd_monitor_recv;
 110 }