2 * services/listen_dnsport.h - listen on port 53 for incoming DNS queries.
4 * Copyright (c) 2007, NLnet Labs. All rights reserved.
6 * This software is open source.
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9 * modification, are permitted provided that the following conditions
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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"
51 * Listening for queries structure.
52 * Contains list of query-listen sockets.
54 struct listen_dnsport {
55 /** Base for select calls */
56 struct comm_base* base;
58 /** buffer shared by UDP connections, since there is only one
59 datagram at any time. */
60 ldns_buffer* udp_buff;
62 /** list of comm points used to get incoming events */
63 struct listen_list* cps;
67 * Single linked list to store event points.
71 struct listen_list* next;
73 struct comm_point* com;
84 /** udp ipv6 (v4mapped) for use with ancillary data */
86 /** ssl over tcp type */
91 * Single linked list to store shared ports that have been
92 * opened for use by all threads.
96 struct listen_port* next;
97 /** file descriptor, open and ready for use */
99 /** type of file descriptor, udp or tcp */
100 enum listen_type ftype;
104 * Create shared listening ports
105 * Getaddrinfo, create socket, bind and listen to zero or more
106 * interfaces for IP4 and/or IP6, for UDP and/or TCP.
107 * On the given port number. It creates the sockets.
108 * @param cfg: settings on what ports to open.
109 * @return: linked list of ports or NULL on error.
111 struct listen_port* listening_ports_open(struct config_file* cfg);
114 * Close and delete the (list of) listening ports.
116 void listening_ports_free(struct listen_port* list);
119 * Create commpoints with for this thread for the shared ports.
120 * @param base: the comm_base that provides event functionality.
121 * for default all ifs.
122 * @param ports: the list of shared ports.
123 * @param bufsize: size of datagram buffer.
124 * @param tcp_accept_count: max number of simultaneous TCP connections
126 * @param sslctx: nonNULL if ssl context.
127 * @param cb: callback function when a request arrives. It is passed
128 * the packet and user argument. Return true to send a reply.
129 * @param cb_arg: user data argument for callback function.
130 * @return: the malloced listening structure, ready for use. NULL on error.
132 struct listen_dnsport* listen_create(struct comm_base* base,
133 struct listen_port* ports, size_t bufsize, int tcp_accept_count,
134 void* sslctx, comm_point_callback_t* cb, void* cb_arg);
137 * delete the listening structure
138 * @param listen: listening structure.
140 void listen_delete(struct listen_dnsport* listen);
143 * delete listen_list of commpoints. Calls commpointdelete() on items.
144 * This may close the fds or not depending on flags.
145 * @param list: to delete.
147 void listen_list_delete(struct listen_list* list);
150 * get memory size used by the listening structs
151 * @param listen: listening structure.
152 * @return: size in bytes.
154 size_t listen_get_mem(struct listen_dnsport* listen);
157 * stop accept handlers for TCP (until enabled again)
158 * @param listen: listening structure.
160 void listen_stop_accept(struct listen_dnsport* listen);
163 * start accept handlers for TCP (was stopped before)
164 * @param listen: listening structure.
166 void listen_start_accept(struct listen_dnsport* listen);
169 * Create and bind nonblocking UDP socket
170 * @param family: for socket call.
171 * @param socktype: for socket call.
172 * @param addr: for bind call.
173 * @param addrlen: for bind call.
174 * @param v6only: if enabled, IP6 sockets get IP6ONLY option set.
175 * if enabled with value 2 IP6ONLY option is disabled.
176 * @param inuse: on error, this is set true if the port was in use.
177 * @param noproto: on error, this is set true if cause is that the
178 IPv6 proto (family) is not available.
179 * @param rcv: set size on rcvbuf with socket option, if 0 it is not set.
180 * @param snd: set size on sndbuf with socket option, if 0 it is not set.
181 * @return: the socket. -1 on error.
183 int create_udp_sock(int family, int socktype, struct sockaddr* addr,
184 socklen_t addrlen, int v6only, int* inuse, int* noproto, int rcv,
188 * Create and bind TCP listening socket
189 * @param addr: address info ready to make socket.
190 * @param v6only: enable ip6 only flag on ip6 sockets.
191 * @param noproto: if error caused by lack of protocol support.
192 * @return: the socket. -1 on error.
194 int create_tcp_accept_sock(struct addrinfo *addr, int v6only, int* noproto);
196 #endif /* LISTEN_DNSPORT_H */