sd-rtnl: improve detection of broadcast messages

[thirdparty/systemd.git] / src / libsystemd / sd-rtnl / rtnl-internal.h

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

#pragma once

/***
  This file is part of systemd.

  Copyright 2013 Tom Gundersen <teg@jklm.no>

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <linux/netlink.h>

#include "refcnt.h"
#include "prioq.h"
#include "list.h"

#include "sd-rtnl.h"

#include "rtnl-types.h"

#define RTNL_DEFAULT_TIMEOUT ((usec_t) (25 * USEC_PER_SEC))

#define RTNL_WQUEUE_MAX 1024
#define RTNL_RQUEUE_MAX 64*1024

#define RTNL_CONTAINER_DEPTH 32

struct reply_callback {
        sd_rtnl_message_handler_t callback;
        void *userdata;
        usec_t timeout;
        uint64_t serial;
        unsigned prioq_idx;
};

struct match_callback {
        sd_rtnl_message_handler_t callback;
        uint16_t type;
        void *userdata;

        LIST_FIELDS(struct match_callback, match_callbacks);
};

struct sd_rtnl {
        RefCount n_ref;

        int fd;

        union {
                struct sockaddr sa;
                struct sockaddr_nl nl;
        } sockaddr;

        sd_rtnl_message **rqueue;
        unsigned rqueue_size;
        size_t rqueue_allocated;

        sd_rtnl_message **rqueue_partial;
        unsigned rqueue_partial_size;
        size_t rqueue_partial_allocated;

        sd_rtnl_message **wqueue;
        unsigned wqueue_size;
        size_t wqueue_allocated;

        struct nlmsghdr *rbuffer;
        size_t rbuffer_allocated;

        bool processing:1;

        uint32_t serial;

        struct Prioq *reply_callbacks_prioq;
        Hashmap *reply_callbacks;

        LIST_HEAD(struct match_callback, match_callbacks);

        pid_t original_pid;

        sd_event_source *io_event_source;
        sd_event_source *time_event_source;
        sd_event_source *exit_event_source;
        sd_event *event;
};

struct sd_rtnl_message {
        RefCount n_ref;

        sd_rtnl *rtnl;

        struct nlmsghdr *hdr;
        const struct NLTypeSystem *(container_type_system[RTNL_CONTAINER_DEPTH]); /* the type of the container and all its parents */
        size_t container_offsets[RTNL_CONTAINER_DEPTH]; /* offset from hdr to each container's start */
        unsigned n_containers; /* number of containers */
        size_t next_rta_offset; /* offset from hdr to next rta */
        size_t *rta_offset_tb[RTNL_CONTAINER_DEPTH];
        unsigned short rta_tb_size[RTNL_CONTAINER_DEPTH];
        bool sealed:1;
        bool broadcast:1;

        sd_rtnl_message *next; /* next in a chain of multi-part messages */
};

int message_new(sd_rtnl *rtnl, sd_rtnl_message **ret, uint16_t type);

int socket_write_message(sd_rtnl *nl, sd_rtnl_message *m);
int socket_read_message(sd_rtnl *nl);

int rtnl_rqueue_make_room(sd_rtnl *rtnl);
int rtnl_rqueue_partial_make_room(sd_rtnl *rtnl);

int rtnl_message_read_internal(sd_rtnl_message *m, unsigned short type, void **data);
int rtnl_message_parse(sd_rtnl_message *m,
                       size_t **rta_offset_tb,
                       unsigned short *rta_tb_size,
                       int max,
                       struct rtattr *rta,
                       unsigned int rt_len);

/* Make sure callbacks don't destroy the rtnl connection */
#define RTNL_DONT_DESTROY(rtnl) \
        _cleanup_rtnl_unref_ _unused_ sd_rtnl *_dont_destroy_##rtnl = sd_rtnl_ref(rtnl)