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/**
* @file
* MDNS responder private definitions
*/
/*
* Copyright (c) 2015 Verisure Innovation AB
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Erik Ekman <erik@kryo.se>
* Author: Jasper Verschueren <jasper.verschueren@apart-audio.com>
*
*/
#ifndef LWIP_HDR_MDNS_PRIV_H
#define LWIP_HDR_MDNS_PRIV_H
#include "lwip/apps/mdns.h"
#include "lwip/apps/mdns_opts.h"
#include "lwip/pbuf.h"
#ifdef __cplusplus
extern "C" {
#endif
#if LWIP_MDNS_RESPONDER
#define MDNS_READNAME_ERROR 0xFFFF
#define NUM_DOMAIN_OFFSETS 10
#define SRV_PRIORITY 0
#define SRV_WEIGHT 0
/* mDNS TTL: (RFC6762 section 10)
* - 120 seconds if the hostname appears somewhere in the RR
* - 75 minutes if not (4500 seconds)
* - 10 seconds if responding to a legacy query
*/
#define MDNS_TTL_10 10
#define MDNS_TTL_120 120
#define MDNS_TTL_4500 4500
/* RFC6762 section 8.1: If fifteen conflicts occur within any ten-second period,
* then the host MUST wait at least five seconds before each successive
* additional probe attempt.
*/
#define MDNS_PROBE_MAX_CONFLICTS_BEFORE_RATE_LIMIT 15
#define MDNS_PROBE_MAX_CONFLICTS_TIME_WINDOW 10000
#define MDNS_PROBE_MAX_CONFLICTS_TIMEOUT 5000
#if LWIP_MDNS_SEARCH
/** Description of a search request */
struct mdns_request {
/** Name of service, like 'myweb' */
char name[MDNS_LABEL_MAXLEN + 1];
/** Type of service, like '_http' or '_services._dns-sd' */
struct mdns_domain service;
/** Callback function called for each response */
search_result_fn_t result_fn;
void *arg;
/** Protocol, TCP or UDP */
u16_t proto;
/** Query type (PTR, SRV, ...) */
u8_t qtype;
/** PTR only request. */
u16_t only_ptr;
};
#endif
/** Description of a service */
struct mdns_service {
/** TXT record to answer with */
struct mdns_domain txtdata;
/** Name of service, like 'myweb' */
char name[MDNS_LABEL_MAXLEN + 1];
/** Type of service, like '_http' */
char service[MDNS_LABEL_MAXLEN + 1];
/** Callback function and userdata
* to update txtdata buffer */
service_get_txt_fn_t txt_fn;
void *txt_userdata;
/** Protocol, TCP or UDP */
u16_t proto;
/** Port of the service */
u16_t port;
};
/** mDNS output packet */
struct mdns_outpacket {
/** Packet data */
struct pbuf *pbuf;
/** Current write offset in packet */
u16_t write_offset;
/** Number of questions written */
u16_t questions;
/** Number of normal answers written */
u16_t answers;
/** Number of authoritative answers written */
u16_t authoritative;
/** Number of additional answers written */
u16_t additional;
/** Offsets for written domain names in packet.
* Used for compression */
u16_t domain_offsets[NUM_DOMAIN_OFFSETS];
};
/** mDNS output message */
struct mdns_outmsg {
/** Identifier. Used in legacy queries */
u16_t tx_id;
/** dns flags */
u8_t flags;
/** Destination IP/port if sent unicast */
ip_addr_t dest_addr;
u16_t dest_port;
/** If all answers in packet should set cache_flush bit */
u8_t cache_flush;
/** If reply should be sent unicast (as requested) */
u8_t unicast_reply_requested;
/** If legacy query. (tx_id needed, and write
* question again in reply before answer) */
u8_t legacy_query;
/** If the query is a probe msg we need to respond immediately. Independent of
* the QU or QM flag. */
u8_t probe_query_recv;
/* Question bitmask for host information */
u8_t host_questions;
/* Questions bitmask per service */
u8_t serv_questions[MDNS_MAX_SERVICES];
/* Reply bitmask for host information */
u8_t host_replies;
/* Bitmask for which reverse IPv6 hosts to answer */
u8_t host_reverse_v6_replies;
/* Reply bitmask per service */
u8_t serv_replies[MDNS_MAX_SERVICES];
#ifdef LWIP_MDNS_SEARCH
/** Search query to send */
struct mdns_request *query;
#endif
};
/** Delayed msg info */
struct mdns_delayed_msg {
/** Signals if a multicast msg needs to be send out */
u8_t multicast_msg_waiting;
/** Multicast timeout for all multicast traffic except probe answers */
u8_t multicast_timeout;
/** Multicast timeout only for probe answers */
u8_t multicast_probe_timeout;
/** Output msg used for delayed multicast responses */
struct mdns_outmsg delayed_msg_multicast;
/** Prefer multicast over unicast timeout -> 25% of TTL = we take 30s as
general delay. */
u8_t multicast_timeout_25TTL;
/** Only send out new unicast message if previous was send */
u8_t unicast_msg_in_use;
/** Output msg used for delayed unicast responses */
struct mdns_outmsg delayed_msg_unicast;
};
/* MDNS states */
typedef enum {
/* MDNS module is off */
MDNS_STATE_OFF,
/* Waiting before probing can be started */
MDNS_STATE_PROBE_WAIT,
/* Probing the unique records */
MDNS_STATE_PROBING,
/* Waiting before announcing the probed unique records */
MDNS_STATE_ANNOUNCE_WAIT,
/* Announcing all records */
MDNS_STATE_ANNOUNCING,
/* Probing and announcing completed */
MDNS_STATE_COMPLETE
} mdns_resp_state_enum_t;
/** Description of a host/netif */
struct mdns_host {
/** Hostname */
char name[MDNS_LABEL_MAXLEN + 1];
/** Pointer to services */
struct mdns_service *services[MDNS_MAX_SERVICES];
/** Number of probes/announces sent for the current name */
u8_t sent_num;
/** State of the mdns responder */
mdns_resp_state_enum_t state;
#if LWIP_IPV4
/** delayed msg struct for IPv4 */
struct mdns_delayed_msg ipv4;
#endif
#if LWIP_IPV6
/** delayed msg struct for IPv6 */
struct mdns_delayed_msg ipv6;
#endif
/** Timestamp of probe conflict saved in list */
u32_t conflict_time[MDNS_PROBE_MAX_CONFLICTS_BEFORE_RATE_LIMIT];
/** Rate limit flag */
u8_t rate_limit_activated;
/** List index for timestamps */
u8_t index;
/** number of conflicts since startup */
u8_t num_conflicts;
};
struct mdns_host* netif_mdns_data(struct netif *netif);
struct udp_pcb* get_mdns_pcb(void);
#endif /* LWIP_MDNS_RESPONDER */
#ifdef __cplusplus
}
#endif
#endif /* LWIP_HDR_MDNS_PRIV_H */
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