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

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   Copyright 2013 Tom Gundersen <teg@jklm.no>
   6 ***/
   7
   8 #include <linux/netlink.h>
   9
  10 #include "sd-netlink.h"
  11
  12 #include "list.h"
  13 #include "netlink-types.h"
  14 #include "prioq.h"
  15 #include "refcnt.h"
  16
  17 #define RTNL_DEFAULT_TIMEOUT ((usec_t) (25 * USEC_PER_SEC))
  18
  19 #define RTNL_WQUEUE_MAX 1024
  20 #define RTNL_RQUEUE_MAX 64*1024
  21
  22 #define RTNL_CONTAINER_DEPTH 32
  23
  24 struct reply_callback {
  25         sd_netlink_message_handler_t callback;
  26         void *userdata;
  27         usec_t timeout;
  28         uint64_t serial;
  29         unsigned prioq_idx;
  30 };
  31
  32 struct match_callback {
  33         sd_netlink_message_handler_t callback;
  34         uint16_t type;
  35         void *userdata;
  36
  37         LIST_FIELDS(struct match_callback, match_callbacks);
  38 };
  39
  40 struct sd_netlink {
  41         RefCount n_ref;
  42
  43         int fd;
  44
  45         union {
  46                 struct sockaddr sa;
  47                 struct sockaddr_nl nl;
  48         } sockaddr;
  49
  50         int protocol;
  51
  52         Hashmap *broadcast_group_refs;
  53         bool broadcast_group_dont_leave:1; /* until we can rely on 4.2 */
  54
  55         sd_netlink_message **rqueue;
  56         unsigned rqueue_size;
  57         size_t rqueue_allocated;
  58
  59         sd_netlink_message **rqueue_partial;
  60         unsigned rqueue_partial_size;
  61         size_t rqueue_partial_allocated;
  62
  63         struct nlmsghdr *rbuffer;
  64         size_t rbuffer_allocated;
  65
  66         bool processing:1;
  67
  68         uint32_t serial;
  69
  70         struct Prioq *reply_callbacks_prioq;
  71         Hashmap *reply_callbacks;
  72
  73         LIST_HEAD(struct match_callback, match_callbacks);
  74
  75         pid_t original_pid;
  76
  77         sd_event_source *io_event_source;
  78         sd_event_source *time_event_source;
  79         sd_event_source *exit_event_source;
  80         sd_event *event;
  81 };
  82
  83 struct netlink_attribute {
  84         size_t offset; /* offset from hdr to attribute */
  85         bool nested:1;
  86         bool net_byteorder:1;
  87 };
  88
  89 struct netlink_container {
  90         const struct NLTypeSystem *type_system; /* the type system of the container */
  91         size_t offset; /* offset from hdr to the start of the container */
  92         struct netlink_attribute *attributes;
  93         unsigned short n_attributes; /* number of attributes in container */
  94 };
  95
  96 struct sd_netlink_message {
  97         RefCount n_ref;
  98
  99         sd_netlink *rtnl;
 100
 101         int protocol;
 102
 103         struct nlmsghdr *hdr;
 104         struct netlink_container containers[RTNL_CONTAINER_DEPTH];
 105         unsigned n_containers; /* number of containers */
 106         bool sealed:1;
 107         bool broadcast:1;
 108
 109         sd_netlink_message *next; /* next in a chain of multi-part messages */
 110 };
 111
 112 int message_new(sd_netlink *rtnl, sd_netlink_message **ret, uint16_t type);
 113 int message_new_empty(sd_netlink *rtnl, sd_netlink_message **ret);
 114
 115 int netlink_open_family(sd_netlink **ret, int family);
 116
 117 int socket_open(int family);
 118 int socket_bind(sd_netlink *nl);
 119 int socket_broadcast_group_ref(sd_netlink *nl, unsigned group);
 120 int socket_broadcast_group_unref(sd_netlink *nl, unsigned group);
 121 int socket_write_message(sd_netlink *nl, sd_netlink_message *m);
 122 int socket_read_message(sd_netlink *nl);
 123
 124 int rtnl_rqueue_make_room(sd_netlink *rtnl);
 125 int rtnl_rqueue_partial_make_room(sd_netlink *rtnl);
 126
 127 /* Make sure callbacks don't destroy the rtnl connection */
 128 #define NETLINK_DONT_DESTROY(rtnl) \
 129         _cleanup_(sd_netlink_unrefp) _unused_ sd_netlink *_dont_destroy_##rtnl = sd_netlink_ref(rtnl)