2 * services/listen_dnsport.h - listen on port 53 for incoming DNS queries.
4 * Copyright (c) 2007, NLnet Labs. All rights reserved.
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39 * This file has functions to get queries from clients.
42 #ifndef LISTEN_DNSPORT_H
43 #define LISTEN_DNSPORT_H
45 #include "util/netevent.h"
52 * Listening for queries structure.
53 * Contains list of query-listen sockets.
55 struct listen_dnsport {
56 /** Base for select calls */
57 struct comm_base* base;
59 /** buffer shared by UDP connections, since there is only one
60 datagram at any time. */
61 struct sldns_buffer* udp_buff;
63 /** list of comm points used to get incoming events */
64 struct listen_list* cps;
68 * Single linked list to store event points.
72 struct listen_list* next;
74 struct comm_point* com;
85 /** udp ipv6 (v4mapped) for use with ancillary data */
87 /** ssl over tcp type */
92 * Single linked list to store shared ports that have been
93 * opened for use by all threads.
97 struct listen_port* next;
98 /** file descriptor, open and ready for use */
100 /** type of file descriptor, udp or tcp */
101 enum listen_type ftype;
105 * Create shared listening ports
106 * Getaddrinfo, create socket, bind and listen to zero or more
107 * interfaces for IP4 and/or IP6, for UDP and/or TCP.
108 * On the given port number. It creates the sockets.
109 * @param cfg: settings on what ports to open.
110 * @param reuseport: set to true if you want reuseport, or NULL to not have it,
111 * set to false on exit if reuseport failed to apply (because of no
113 * @return: linked list of ports or NULL on error.
115 struct listen_port* listening_ports_open(struct config_file* cfg,
119 * Close and delete the (list of) listening ports.
121 void listening_ports_free(struct listen_port* list);
124 * Create commpoints with for this thread for the shared ports.
125 * @param base: the comm_base that provides event functionality.
126 * for default all ifs.
127 * @param ports: the list of shared ports.
128 * @param bufsize: size of datagram buffer.
129 * @param tcp_accept_count: max number of simultaneous TCP connections
131 * @param sslctx: nonNULL if ssl context.
132 * @param dtenv: nonNULL if dnstap enabled.
133 * @param cb: callback function when a request arrives. It is passed
134 * the packet and user argument. Return true to send a reply.
135 * @param cb_arg: user data argument for callback function.
136 * @return: the malloced listening structure, ready for use. NULL on error.
138 struct listen_dnsport* listen_create(struct comm_base* base,
139 struct listen_port* ports, size_t bufsize, int tcp_accept_count,
140 void* sslctx, struct dt_env *dtenv, comm_point_callback_t* cb,
144 * delete the listening structure
145 * @param listen: listening structure.
147 void listen_delete(struct listen_dnsport* listen);
150 * delete listen_list of commpoints. Calls commpointdelete() on items.
151 * This may close the fds or not depending on flags.
152 * @param list: to delete.
154 void listen_list_delete(struct listen_list* list);
157 * get memory size used by the listening structs
158 * @param listen: listening structure.
159 * @return: size in bytes.
161 size_t listen_get_mem(struct listen_dnsport* listen);
164 * stop accept handlers for TCP (until enabled again)
165 * @param listen: listening structure.
167 void listen_stop_accept(struct listen_dnsport* listen);
170 * start accept handlers for TCP (was stopped before)
171 * @param listen: listening structure.
173 void listen_start_accept(struct listen_dnsport* listen);
176 * Create and bind nonblocking UDP socket
177 * @param family: for socket call.
178 * @param socktype: for socket call.
179 * @param addr: for bind call.
180 * @param addrlen: for bind call.
181 * @param v6only: if enabled, IP6 sockets get IP6ONLY option set.
182 * if enabled with value 2 IP6ONLY option is disabled.
183 * @param inuse: on error, this is set true if the port was in use.
184 * @param noproto: on error, this is set true if cause is that the
185 IPv6 proto (family) is not available.
186 * @param rcv: set size on rcvbuf with socket option, if 0 it is not set.
187 * @param snd: set size on sndbuf with socket option, if 0 it is not set.
188 * @param listen: if true, this is a listening UDP port, eg port 53, and
189 * set SO_REUSEADDR on it.
190 * @param reuseport: if nonNULL and true, try to set SO_REUSEPORT on
191 * listening UDP port. Set to false on return if it failed to do so.
192 * @return: the socket. -1 on error.
194 int create_udp_sock(int family, int socktype, struct sockaddr* addr,
195 socklen_t addrlen, int v6only, int* inuse, int* noproto, int rcv,
196 int snd, int listen, int* reuseport);
199 * Create and bind TCP listening socket
200 * @param addr: address info ready to make socket.
201 * @param v6only: enable ip6 only flag on ip6 sockets.
202 * @param noproto: if error caused by lack of protocol support.
203 * @param reuseport: if nonNULL and true, try to set SO_REUSEPORT on
204 * listening UDP port. Set to false on return if it failed to do so.
205 * @return: the socket. -1 on error.
207 int create_tcp_accept_sock(struct addrinfo *addr, int v6only, int* noproto,
211 * Create and bind local listening socket
212 * @param path: path to the socket.
213 * @param noproto: on error, this is set true if cause is that local sockets
215 * @return: the socket. -1 on error.
217 int create_local_accept_sock(const char* path, int* noproto);
219 #endif /* LISTEN_DNSPORT_H */