src/libsystemd/sd-netlink/netlink-internal.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2013 Tom Gundersen <teg@jklm.no>
   8
   9   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 #include <linux/netlink.h>
  24
  25 #include "sd-netlink.h"
  26
  27 #include "list.h"
  28 #include "netlink-types.h"
  29 #include "prioq.h"
  30 #include "refcnt.h"
  31
  32 #define RTNL_DEFAULT_TIMEOUT ((usec_t) (25 * USEC_PER_SEC))
  33
  34 #define RTNL_WQUEUE_MAX 1024
  35 #define RTNL_RQUEUE_MAX 64*1024
  36
  37 #define RTNL_CONTAINER_DEPTH 32
  38
  39 struct reply_callback {
  40         sd_netlink_message_handler_t callback;
  41         void *userdata;
  42         usec_t timeout;
  43         uint64_t serial;
  44         unsigned prioq_idx;
  45 };
  46
  47 struct match_callback {
  48         sd_netlink_message_handler_t callback;
  49         uint16_t type;
  50         void *userdata;
  51
  52         LIST_FIELDS(struct match_callback, match_callbacks);
  53 };
  54
  55 struct sd_netlink {
  56         RefCount n_ref;
  57
  58         int fd;
  59
  60         union {
  61                 struct sockaddr sa;
  62                 struct sockaddr_nl nl;
  63         } sockaddr;
  64
  65         Hashmap *broadcast_group_refs;
  66         bool broadcast_group_dont_leave:1; /* until we can rely on 4.2 */
  67
  68         sd_netlink_message **rqueue;
  69         unsigned rqueue_size;
  70         size_t rqueue_allocated;
  71
  72         sd_netlink_message **rqueue_partial;
  73         unsigned rqueue_partial_size;
  74         size_t rqueue_partial_allocated;
  75
  76         struct nlmsghdr *rbuffer;
  77         size_t rbuffer_allocated;
  78
  79         bool processing:1;
  80
  81         uint32_t serial;
  82
  83         struct Prioq *reply_callbacks_prioq;
  84         Hashmap *reply_callbacks;
  85
  86         LIST_HEAD(struct match_callback, match_callbacks);
  87
  88         pid_t original_pid;
  89
  90         sd_event_source *io_event_source;
  91         sd_event_source *time_event_source;
  92         sd_event_source *exit_event_source;
  93         sd_event *event;
  94 };
  95
  96 struct netlink_attribute {
  97         size_t offset; /* offset from hdr to attribute */
  98         bool nested:1;
  99         bool net_byteorder:1;
 100 };
 101
 102 struct netlink_container {
 103         const struct NLTypeSystem *type_system; /* the type system of the container */
 104         size_t offset; /* offset from hdr to the start of the container */
 105         struct netlink_attribute *attributes;
 106         unsigned short n_attributes; /* number of attributes in container */
 107 };
 108
 109 struct sd_netlink_message {
 110         RefCount n_ref;
 111
 112         sd_netlink *rtnl;
 113
 114         struct nlmsghdr *hdr;
 115         struct netlink_container containers[RTNL_CONTAINER_DEPTH];
 116         unsigned n_containers; /* number of containers */
 117         bool sealed:1;
 118         bool broadcast:1;
 119
 120         sd_netlink_message *next; /* next in a chain of multi-part messages */
 121 };
 122
 123 int message_new(sd_netlink *rtnl, sd_netlink_message **ret, uint16_t type);
 124 int message_new_empty(sd_netlink *rtnl, sd_netlink_message **ret);
 125
 126 int socket_open(int family);
 127 int socket_bind(sd_netlink *nl);
 128 int socket_broadcast_group_ref(sd_netlink *nl, unsigned group);
 129 int socket_broadcast_group_unref(sd_netlink *nl, unsigned group);
 130 int socket_write_message(sd_netlink *nl, sd_netlink_message *m);
 131 int socket_read_message(sd_netlink *nl);
 132
 133 int rtnl_rqueue_make_room(sd_netlink *rtnl);
 134 int rtnl_rqueue_partial_make_room(sd_netlink *rtnl);
 135
 136 /* Make sure callbacks don't destroy the rtnl connection */
 137 #define NETLINK_DONT_DESTROY(rtnl) \
 138         _cleanup_(sd_netlink_unrefp) _unused_ sd_netlink *_dont_destroy_##rtnl = sd_netlink_ref(rtnl)