/*
* services/outside_network.h - listen to answers from the network
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 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.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 COPYRIGHT
* HOLDER OR CONTRIBUTORS 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.
*/
/**
* \file
*
* This file has functions to send queries to authoritative servers,
* and wait for the pending answer, with timeouts.
*/
#ifndef OUTSIDE_NETWORK_H
#define OUTSIDE_NETWORK_H
#include "util/rbtree.h"
#include "util/netevent.h"
#include "dnstap/dnstap_config.h"
struct pending;
struct pending_timeout;
struct ub_randstate;
struct pending_tcp;
struct waiting_tcp;
struct waiting_udp;
struct reuse_tcp;
struct infra_cache;
struct port_comm;
struct port_if;
struct sldns_buffer;
struct serviced_query;
struct dt_env;
struct edns_option;
struct module_env;
struct module_qstate;
struct query_info;
/**
* Send queries to outside servers and wait for answers from servers.
* Contains answer-listen sockets.
*/
struct outside_network {
/** Base for select calls */
struct comm_base* base;
/** pointer to time in seconds */
time_t* now_secs;
/** pointer to time in microseconds */
struct timeval* now_tv;
/** buffer shared by UDP connections, since there is only one
datagram at any time. */
struct sldns_buffer* udp_buff;
/** serviced_callbacks malloc overhead when processing multiple
* identical serviced queries to the same server. */
size_t svcd_overhead;
/** use x20 bits to encode additional ID random bits */
int use_caps_for_id;
/** outside network wants to quit. Stop queued msgs from sent. */
int want_to_quit;
/** number of unwanted replies received (for statistics) */
size_t unwanted_replies;
/** cumulative total of unwanted replies (for defense) */
size_t unwanted_total;
/** threshold when to take defensive action. If 0 then never. */
size_t unwanted_threshold;
/** what action to take, called when defensive action is needed */
void (*unwanted_action)(void*);
/** user param for action */
void* unwanted_param;
/** linked list of available commpoints, unused file descriptors,
* for use as outgoing UDP ports. cp.fd=-1 in them. */
struct port_comm* unused_fds;
/** if udp is done */
int do_udp;
/** if udp is delay-closed (delayed answers do not meet closed port)*/
int delayclose;
/** timeout for delayclose */
struct timeval delay_tv;
/** if we perform udp-connect, connect() for UDP socket to mitigate
* ICMP side channel leakage */
int udp_connect;
/** array of outgoing IP4 interfaces */
struct port_if* ip4_ifs;
/** number of outgoing IP4 interfaces */
int num_ip4;
/** array of outgoing IP6 interfaces */
struct port_if* ip6_ifs;
/** number of outgoing IP6 interfaces */
int num_ip6;
/** pending udp queries waiting to be sent out, waiting for fd */
struct pending* udp_wait_first;
/** last pending udp query in list */
struct pending* udp_wait_last;
/** pending udp answers. sorted by id, addr */
rbtree_type* pending;
/** serviced queries, sorted by qbuf, addr, dnssec */
rbtree_type* serviced;
/** host cache, pointer but not owned by outnet. */
struct infra_cache* infra;
/** where to get random numbers */
struct ub_randstate* rnd;
/** ssl context to create ssl wrapped TCP with DNS connections */
void* sslctx;
/** if SNI will be used for TLS connections */
int tls_use_sni;
#ifdef USE_DNSTAP
/** dnstap environment */
struct dt_env* dtenv;
#endif
/** maximum segment size of tcp socket */
int tcp_mss;
/** IP_TOS socket option requested on the sockets */
int ip_dscp;
/**
* Array of tcp pending used for outgoing TCP connections.
* Each can be used to establish a TCP connection with a server.
* The file descriptors are -1 if they are free, and need to be
* opened for the tcp connection. Can be used for ip4 and ip6.
*/
struct pending_tcp **tcp_conns;
/** number of tcp communication points. */
size_t num_tcp;
/** number of tcp communication points in use. */
size_t num_tcp_outgoing;
/**
* tree of still-open and waiting tcp connections for reuse.
* can be closed and reopened to get a new tcp connection.
* or reused to the same destination again. with timeout to close.
* Entries are of type struct reuse_tcp.
* The entries are both active and empty connections.
*/
rbtree_type tcp_reuse;
/** max number of tcp_reuse entries we want to keep open */
size_t tcp_reuse_max;
/** first and last(oldest) in lru list of reuse connections.
* the oldest can be closed to get a new free pending_tcp if needed
* The list contains empty connections, that wait for timeout or
* a new query that can use the existing connection. */
struct reuse_tcp* tcp_reuse_first, *tcp_reuse_last;
/** list of tcp comm points that are free for use */
struct pending_tcp* tcp_free;
/** list of tcp queries waiting for a buffer */
struct waiting_tcp* tcp_wait_first;
/** last of waiting query list */
struct waiting_tcp* tcp_wait_last;
};
/**
* Outgoing interface. Ports available and currently used are tracked
* per interface
*/
struct port_if {
/** address ready to allocate new socket (except port no). */
struct sockaddr_storage addr;
/** length of addr field */
socklen_t addrlen;
/** prefix length of network address (in bits), for randomisation.
* if 0, no randomisation. */
int pfxlen;
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
/** the available ports array. These are unused.
* Only the first total-inuse part is filled. */
int* avail_ports;
/** the total number of available ports (size of the array) */
int avail_total;
#endif
/** array of the commpoints currently in use.
* allocated for max number of fds, first part in use. */
struct port_comm** out;
/** max number of fds, size of out array */
int maxout;
/** number of commpoints (and thus also ports) in use */
int inuse;
};
/**
* Outgoing commpoint for UDP port.
*/
struct port_comm {
/** next in free list */
struct port_comm* next;
/** which port number (when in use) */
int number;
/** interface it is used in */
struct port_if* pif;
/** index in the out array of the interface */
int index;
/** number of outstanding queries on this port */
int num_outstanding;
/** UDP commpoint, fd=-1 if not in use */
struct comm_point* cp;
};
/**
* Reuse TCP connection, still open can be used again.
*/
struct reuse_tcp {
/** rbtree node with links in tcp_reuse tree. key is NULL when not
* in tree. Both active and empty connections are in the tree.
* key is a pointer to this structure, the members used to compare
* are the sockaddr and and then is-ssl bool, and then ptr value is
* used in case the same address exists several times in the tree
* when there are multiple connections to the same destination to
* make the rbtree items unique. */
rbnode_type node;
/** the key for the tcp_reuse tree. address of peer, ip4 or ip6,
* and port number of peer */
struct sockaddr_storage addr;
/** length of addr */
socklen_t addrlen;
/** also key for tcp_reuse tree, if ssl is used */
int is_ssl;
/** lru chain, so that the oldest can be removed to get a new
* connection when all are in (re)use. oldest is last in list.
* The lru only contains empty connections waiting for reuse,
* the ones with active queries are not on the list because they
* do not need to be closed to make space for others. They already
* service a query so the close for another query does not help
* service a larger number of queries. */
struct reuse_tcp* lru_next, *lru_prev;
/** true if the reuse_tcp item is on the lru list with empty items */
int item_on_lru_list;
/** the connection to reuse, the fd is non-1 and is open.
* the addr and port determine where the connection is going,
* and is key to the rbtree. The SSL ptr determines if it is
* a TLS connection or a plain TCP connection there. And TLS
* or not is also part of the key to the rbtree.
* There is a timeout and read event on the fd, to close it. */
struct pending_tcp* pending;
/**
* The more read again value pointed to by the commpoint
* tcp_more_read_again pointer, so that it exists after commpoint
* delete
*/
int cp_more_read_again;
/**
* The more write again value pointed to by the commpoint
* tcp_more_write_again pointer, so that it exists after commpoint
* delete
*/
int cp_more_write_again;
/** rbtree with other queries waiting on the connection, by ID number,
* of type struct waiting_tcp. It is for looking up received
* answers to the structure for callback. And also to see if ID
* numbers are unused and can be used for a new query.
* The write_wait elements are also in the tree, so that ID numbers
* can be looked up also for them. They are bool write_wait_queued. */
rbtree_type tree_by_id;
/** list of queries waiting to be written on the channel,
* if NULL no queries are waiting to be written and the pending->query
* is the query currently serviced. The first is the next in line.
* They are also in the tree_by_id. Once written, the are removed
* from this list, but stay in the tree. */
struct waiting_tcp* write_wait_first, *write_wait_last;
/** the outside network it is part of */
struct outside_network* outnet;
};
/** max number of queries on a reuse connection */
#define MAX_REUSE_TCP_QUERIES 200
/** timeout for REUSE entries in milliseconds. */
#define REUSE_TIMEOUT 60000
/**
* A query that has an answer pending for it.
*/
struct pending {
/** redblacktree entry, key is the pending struct(id, addr). */
rbnode_type node;
/** the ID for the query. int so that a value out of range can
* be used to signify a pending that is for certain not present in
* the rbtree. (and for which deletion is safe). */
unsigned int id;
/** remote address. */
struct sockaddr_storage addr;
/** length of addr field in use. */
socklen_t addrlen;
/** comm point it was sent on (and reply must come back on). */
struct port_comm* pc;
/** timeout event */
struct comm_timer* timer;
/** callback for the timeout, error or reply to the message */
comm_point_callback_type* cb;
/** callback user argument */
void* cb_arg;
/** the outside network it is part of */
struct outside_network* outnet;
/** the corresponding serviced_query */
struct serviced_query* sq;
/*---- filled if udp pending is waiting -----*/
/** next in waiting list. */
struct pending* next_waiting;
/** timeout in msec */
int timeout;
/** The query itself, the query packet to send. */
uint8_t* pkt;
/** length of query packet. */
size_t pkt_len;
};
/**
* Pending TCP query to server.
*/
struct pending_tcp {
/** next in list of free tcp comm points, or NULL. */
struct pending_tcp* next_free;
/** tcp comm point it was sent on (and reply must come back on). */
struct comm_point* c;
/** the query being serviced, NULL if the pending_tcp is unused. */
struct waiting_tcp* query;
/** the pre-allocated reuse tcp structure. if ->pending is nonNULL
* it is in use and the connection is waiting for reuse.
* It is here for memory pre-allocation, and used to make this
* pending_tcp wait for reuse. */
struct reuse_tcp reuse;
};
/**
* Query waiting for TCP buffer.
*/
struct waiting_tcp {
/**
* next in waiting list.
* if on_tcp_waiting_list==0, this points to the pending_tcp structure.
*/
struct waiting_tcp* next_waiting;
/** if true the item is on the tcp waiting list and next_waiting
* is used for that. If false, the next_waiting points to the
* pending_tcp */
int on_tcp_waiting_list;
/** next and prev in query waiting list for stream connection */
struct waiting_tcp* write_wait_prev, *write_wait_next;
/** true if the waiting_tcp structure is on the write_wait queue */
int write_wait_queued;
/** entry in reuse.tree_by_id, if key is NULL, not in tree, otherwise,
* this struct is key and sorted by ID (from waiting_tcp.id). */
rbnode_type id_node;
/** the ID for the query; checked in reply */
uint16_t id;
/** timeout event; timer keeps running whether the query is
* waiting for a buffer or the tcp reply is pending */
struct comm_timer* timer;
/** timeout in msec */
int timeout;
/** the outside network it is part of */
struct outside_network* outnet;
/** remote address. */
struct sockaddr_storage addr;
/** length of addr field in use. */
socklen_t addrlen;
/**
* The query itself, the query packet to send.
* allocated after the waiting_tcp structure.
*/
uint8_t* pkt;
/** length of query packet. */
size_t pkt_len;
/** callback for the timeout, error or reply to the message,
* or NULL if no user is waiting. the entry uses an ID number.
* a query that was written is no longer needed, but the ID number
* and a reply will come back and can be ignored if NULL */
comm_point_callback_type* cb;
/** callback user argument */
void* cb_arg;
/** if it uses ssl upstream */
int ssl_upstream;
/** ref to the tls_auth_name from the serviced_query */
char* tls_auth_name;
/** the packet was involved in an error, to stop looping errors */
int error_count;
};
/**
* Callback to party interested in serviced query results.
*/
struct service_callback {
/** next in callback list */
struct service_callback* next;
/** callback function */
comm_point_callback_type* cb;
/** user argument for callback function */
void* cb_arg;
};
/** fallback size for fragmentation for EDNS in IPv4 */
#define EDNS_FRAG_SIZE_IP4 1472
/** fallback size for EDNS in IPv6, fits one fragment with ip6-tunnel-ids */
#define EDNS_FRAG_SIZE_IP6 1232
/**
* Query service record.
* Contains query and destination. UDP, TCP, EDNS are all tried.
* complete with retries and timeouts. A number of interested parties can
* receive a callback.
*/
struct serviced_query {
/** The rbtree node, key is this record */
rbnode_type node;
/** The query that needs to be answered. Starts with flags u16,
* then qdcount, ..., including qname, qtype, qclass. Does not include
* EDNS record. */
uint8_t* qbuf;
/** length of qbuf. */
size_t qbuflen;
/** If an EDNS section is included, the DO/CD bit will be turned on. */
int dnssec;
/** We want signatures, or else the answer is likely useless */
int want_dnssec;
/** ignore capsforid */
int nocaps;
/** tcp upstream used, use tcp, or ssl_upstream for SSL */
int tcp_upstream, ssl_upstream;
/** the name of the tls authentication name, eg. 'ns.example.com'
* or NULL */
char* tls_auth_name;
/** where to send it */
struct sockaddr_storage addr;
/** length of addr field in use. */
socklen_t addrlen;
/** zone name, uncompressed domain name in wireformat */
uint8_t* zone;
/** length of zone name */
size_t zonelen;
/** qtype */
int qtype;
/** current status */
enum serviced_query_status {
/** initial status */
serviced_initial,
/** UDP with EDNS sent */
serviced_query_UDP_EDNS,
/** UDP without EDNS sent */
serviced_query_UDP,
/** TCP with EDNS sent */
serviced_query_TCP_EDNS,
/** TCP without EDNS sent */
serviced_query_TCP,
/** probe to test noEDNS0 (EDNS gives FORMERRorNOTIMP) */
serviced_query_UDP_EDNS_fallback,
/** probe to test TCP noEDNS0 (EDNS gives FORMERRorNOTIMP) */
serviced_query_TCP_EDNS_fallback,
/** send UDP query with EDNS1480 (or 1280) */
serviced_query_UDP_EDNS_FRAG
}
/** variable with current status */
status;
/** true if serviced_query is scheduled for deletion already */
int to_be_deleted;
/** number of UDP retries */
int retry;
/** time last UDP was sent */
struct timeval last_sent_time;
/** rtt of last message */
int last_rtt;
/** do we know edns probe status already, for UDP_EDNS queries */
int edns_lame_known;
/** edns options to use for sending upstream packet */
struct edns_option* opt_list;
/** outside network this is part of */
struct outside_network* outnet;
/** list of interested parties that need callback on results. */
struct service_callback* cblist;
/** the UDP or TCP query that is pending, see status which */
void* pending;
/** block size with which to pad encrypted queries (default: 128) */
size_t padding_block_size;
};
/**
* Create outside_network structure with N udp ports.
* @param base: the communication base to use for event handling.
* @param bufsize: size for network buffers.
* @param num_ports: number of udp ports to open per interface.
* @param ifs: interface names (or NULL for default interface).
* These interfaces must be able to access all authoritative servers.
* @param num_ifs: number of names in array ifs.
* @param do_ip4: service IP4.
* @param do_ip6: service IP6.
* @param num_tcp: number of outgoing tcp buffers to preallocate.
* @param dscp: DSCP to use.
* @param infra: pointer to infra cached used for serviced queries.
* @param rnd: stored to create random numbers for serviced queries.
* @param use_caps_for_id: enable to use 0x20 bits to encode id randomness.
* @param availports: array of available ports.
* @param numavailports: number of available ports in array.
* @param unwanted_threshold: when to take defensive action.
* @param unwanted_action: the action to take.
* @param unwanted_param: user parameter to action.
* @param tcp_mss: maximum segment size of tcp socket.
* @param do_udp: if udp is done.
* @param sslctx: context to create outgoing connections with (if enabled).
* @param delayclose: if not 0, udp sockets are delayed before timeout closure.
* msec to wait on timeouted udp sockets.
* @param tls_use_sni: if SNI is used for TLS connections.
* @param dtenv: environment to send dnstap events with (if enabled).
* @param udp_connect: if the udp_connect option is enabled.
* @return: the new structure (with no pending answers) or NULL on error.
*/
struct outside_network* outside_network_create(struct comm_base* base,
size_t bufsize, size_t num_ports, char** ifs, int num_ifs,
int do_ip4, int do_ip6, size_t num_tcp, int dscp, struct infra_cache* infra,
struct ub_randstate* rnd, int use_caps_for_id, int* availports,
int numavailports, size_t unwanted_threshold, int tcp_mss,
void (*unwanted_action)(void*), void* unwanted_param, int do_udp,
void* sslctx, int delayclose, int tls_use_sni, struct dt_env *dtenv,
int udp_connect);
/**
* Delete outside_network structure.
* @param outnet: object to delete.
*/
void outside_network_delete(struct outside_network* outnet);
/**
* Prepare for quit. Sends no more queries, even if queued up.
* @param outnet: object to prepare for removal
*/
void outside_network_quit_prepare(struct outside_network* outnet);
/**
* Send UDP query, create pending answer.
* Changes the ID for the query to be random and unique for that destination.
* @param sq: serviced query.
* @param packet: wireformat query to send to destination.
* @param timeout: in milliseconds from now.
* @param callback: function to call on error, timeout or reply.
* @param callback_arg: user argument for callback function.
* @return: NULL on error for malloc or socket. Else the pending query object.
*/
struct pending* pending_udp_query(struct serviced_query* sq,
struct sldns_buffer* packet, int timeout, comm_point_callback_type* callback,
void* callback_arg);
/**
* Send TCP query. May wait for TCP buffer. Selects ID to be random, and
* checks id.
* @param sq: serviced query.
* @param packet: wireformat query to send to destination. copied from.
* @param timeout: in milliseconds from now.
* Timer starts running now. Timer may expire if all buffers are used,
* without any query been sent to the server yet.
* @param callback: function to call on error, timeout or reply.
* @param callback_arg: user argument for callback function.
* @return: false on error for malloc or socket. Else the pending TCP object.
*/
struct waiting_tcp* pending_tcp_query(struct serviced_query* sq,
struct sldns_buffer* packet, int timeout, comm_point_callback_type* callback,
void* callback_arg);
/**
* Delete pending answer.
* @param outnet: outside network the pending query is part of.
* Internal feature: if outnet is NULL, p is not unlinked from rbtree.
* @param p: deleted
*/
void pending_delete(struct outside_network* outnet, struct pending* p);
/**
* Perform a serviced query to the authoritative servers.
* Duplicate efforts are detected, and EDNS, TCP and UDP retry is performed.
* @param outnet: outside network, with rbtree of serviced queries.
* @param qinfo: query info.
* @param flags: flags u16 (host format), includes opcode, CD bit.
* @param dnssec: if set, DO bit is set in EDNS queries.
* If the value includes BIT_CD, CD bit is set when in EDNS queries.
* If the value includes BIT_DO, DO bit is set when in EDNS queries.
* @param want_dnssec: signatures are needed, without EDNS the answer is
* likely to be useless.
* @param nocaps: ignore use_caps_for_id and use unperturbed qname.
* @param tcp_upstream: use TCP for upstream queries.
* @param ssl_upstream: use SSL for upstream queries.
* @param tls_auth_name: when ssl_upstream is true, use this name to check
* the server's peer certificate.
* @param addr: to which server to send the query.
* @param addrlen: length of addr.
* @param zone: name of the zone of the delegation point. wireformat dname.
This is the delegation point name for which the server is deemed
authoritative.
* @param zonelen: length of zone.
* @param qstate: module qstate. Mainly for inspecting the available
* edns_opts_lists.
* @param callback: callback function.
* @param callback_arg: user argument to callback function.
* @param buff: scratch buffer to create query contents in. Empty on exit.
* @param env: the module environment.
* @return 0 on error, or pointer to serviced query that is used to answer
* this serviced query may be shared with other callbacks as well.
*/
struct serviced_query* outnet_serviced_query(struct outside_network* outnet,
struct query_info* qinfo, uint16_t flags, int dnssec, int want_dnssec,
int nocaps, int tcp_upstream, int ssl_upstream, char* tls_auth_name,
struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* zone,
size_t zonelen, struct module_qstate* qstate,
comm_point_callback_type* callback, void* callback_arg,
struct sldns_buffer* buff, struct module_env* env);
/**
* Remove service query callback.
* If that leads to zero callbacks, the query is completely cancelled.
* @param sq: serviced query to adjust.
* @param cb_arg: callback argument of callback that needs removal.
* same as the callback_arg to outnet_serviced_query().
*/
void outnet_serviced_query_stop(struct serviced_query* sq, void* cb_arg);
/**
* Get memory size in use by outside network.
* Counts buffers and outstanding query (serviced queries) malloced data.
* @param outnet: outside network structure.
* @return size in bytes.
*/
size_t outnet_get_mem(struct outside_network* outnet);
/**
* Get memory size in use by serviced query while it is servicing callbacks.
* This takes into account the pre-deleted status of it; it will be deleted
* when the callbacks are done.
* @param sq: serviced query.
* @return size in bytes.
*/
size_t serviced_get_mem(struct serviced_query* sq);
/** Pick random ID value for a tcp stream, avoids existing IDs. */
uint16_t reuse_tcp_select_id(struct reuse_tcp* reuse,
struct outside_network* outnet);
/** find element in tree by id */
struct waiting_tcp* reuse_tcp_by_id_find(struct reuse_tcp* reuse, uint16_t id);
/** insert element in tree by id */
void reuse_tree_by_id_insert(struct reuse_tcp* reuse, struct waiting_tcp* w);
/** delete readwait waiting_tcp elements, deletes the elements in the list */
void reuse_del_readwait(rbtree_type* tree_by_id);
/** get TCP file descriptor for address, returns -1 on failure,
* tcp_mss is 0 or maxseg size to set for TCP packets. */
int outnet_get_tcp_fd(struct sockaddr_storage* addr, socklen_t addrlen, int tcp_mss, int dscp);
/**
* Create udp commpoint suitable for sending packets to the destination.
* @param outnet: outside_network with the comm_base it is attached to,
* with the outgoing interfaces chosen from, and rnd gen for random.
* @param cb: callback function for the commpoint.
* @param cb_arg: callback argument for cb.
* @param to_addr: intended destination.
* @param to_addrlen: length of to_addr.
* @return commpoint that you can comm_point_send_udp_msg with, or NULL.
*/
struct comm_point* outnet_comm_point_for_udp(struct outside_network* outnet,
comm_point_callback_type* cb, void* cb_arg,
struct sockaddr_storage* to_addr, socklen_t to_addrlen);
/**
* Create tcp commpoint suitable for communication to the destination.
* It also performs connect() to the to_addr.
* @param outnet: outside_network with the comm_base it is attached to,
* and the tcp_mss.
* @param cb: callback function for the commpoint.
* @param cb_arg: callback argument for cb.
* @param to_addr: intended destination.
* @param to_addrlen: length of to_addr.
* @param query: initial packet to send writing, in buffer. It is copied
* to the commpoint buffer that is created.
* @param timeout: timeout for the TCP connection.
* timeout in milliseconds, or -1 for no (change to the) timeout.
* So seconds*1000.
* @param ssl: set to true for TLS.
* @param host: hostname for host name verification of TLS (or NULL if no TLS).
* @return tcp_out commpoint, or NULL.
*/
struct comm_point* outnet_comm_point_for_tcp(struct outside_network* outnet,
comm_point_callback_type* cb, void* cb_arg,
struct sockaddr_storage* to_addr, socklen_t to_addrlen,
struct sldns_buffer* query, int timeout, int ssl, char* host);
/**
* Create http commpoint suitable for communication to the destination.
* Creates the http request buffer. It also performs connect() to the to_addr.
* @param outnet: outside_network with the comm_base it is attached to,
* and the tcp_mss.
* @param cb: callback function for the commpoint.
* @param cb_arg: callback argument for cb.
* @param to_addr: intended destination.
* @param to_addrlen: length of to_addr.
* @param timeout: timeout for the TCP connection.
* timeout in milliseconds, or -1 for no (change to the) timeout.
* So seconds*1000.
* @param ssl: set to true for https.
* @param host: hostname to use for the destination. part of http request.
* @param path: pathname to lookup, eg. name of the file on the destination.
* @return http_out commpoint, or NULL.
*/
struct comm_point* outnet_comm_point_for_http(struct outside_network* outnet,
comm_point_callback_type* cb, void* cb_arg,
struct sockaddr_storage* to_addr, socklen_t to_addrlen, int timeout,
int ssl, char* host, char* path);
/** connect tcp connection to addr, 0 on failure */
int outnet_tcp_connect(int s, struct sockaddr_storage* addr, socklen_t addrlen);
/** callback for incoming udp answers from the network */
int outnet_udp_cb(struct comm_point* c, void* arg, int error,
struct comm_reply *reply_info);
/** callback for pending tcp connections */
int outnet_tcp_cb(struct comm_point* c, void* arg, int error,
struct comm_reply *reply_info);
/** callback for udp timeout */
void pending_udp_timer_cb(void *arg);
/** callback for udp delay for timeout */
void pending_udp_timer_delay_cb(void *arg);
/** callback for outgoing TCP timer event */
void outnet_tcptimer(void* arg);
/** callback for serviced query UDP answers */
int serviced_udp_callback(struct comm_point* c, void* arg, int error,
struct comm_reply* rep);
/** TCP reply or error callback for serviced queries */
int serviced_tcp_callback(struct comm_point* c, void* arg, int error,
struct comm_reply* rep);
/** compare function of pending rbtree */
int pending_cmp(const void* key1, const void* key2);
/** compare function of serviced query rbtree */
int serviced_cmp(const void* key1, const void* key2);
/** compare function of reuse_tcp rbtree in outside_network struct */
int reuse_cmp(const void* key1, const void* key2);
/** compare function of reuse_tcp tree_by_id rbtree */
int reuse_id_cmp(const void* key1, const void* key2);
#endif /* OUTSIDE_NETWORK_H */