Edit: /usr/include/bind9/isc/netmgr.h (15732B)
/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
#pragma once
#include
#include
#include
#include
/*
* Replacement for isc_sockettype_t provided by socket.h.
*/
typedef enum {
isc_socktype_tcp = 1,
isc_socktype_udp = 2,
isc_socktype_unix = 3,
isc_socktype_raw = 4
} isc_socktype_t;
typedef void (*isc_nm_recv_cb_t)(isc_nmhandle_t *handle, isc_result_t eresult,
isc_region_t *region, void *cbarg);
/*%<
* Callback function to be used when receiving a packet.
*
* 'handle' the handle that can be used to send back the answer.
* 'eresult' the result of the event.
* 'region' contains the received data, if any. It will be freed
* after return by caller.
* 'cbarg' the callback argument passed to isc_nm_listenudp(),
* isc_nm_listentcpdns(), or isc_nm_read().
*/
typedef isc_result_t (*isc_nm_accept_cb_t)(isc_nmhandle_t *handle,
isc_result_t result, void *cbarg);
/*%<
* Callback function to be used when accepting a connection. (This differs
* from isc_nm_cb_t below in that it returns a result code.)
*
* 'handle' the handle that can be used to send back the answer.
* 'eresult' the result of the event.
* 'cbarg' the callback argument passed to isc_nm_listentcp() or
* isc_nm_listentcpdns().
*/
typedef void (*isc_nm_cb_t)(isc_nmhandle_t *handle, isc_result_t result,
void *cbarg);
/*%<
* Callback function for other network completion events (send, connect).
*
* 'handle' the handle on which the event took place.
* 'eresult' the result of the event.
* 'cbarg' the callback argument passed to isc_nm_send(),
* isc_nm_tcp_connect(), or isc_nm_listentcp()
*/
typedef void (*isc_nm_opaquecb_t)(void *arg);
/*%<
* Opaque callback function, used for isc_nmhandle 'reset' and 'free'
* callbacks.
*/
typedef void (*isc_nm_workcb_t)(void *arg);
typedef void (*isc_nm_after_workcb_t)(void *arg, isc_result_t result);
/*%<
* Callback functions for libuv threadpool work (see uv_work_t)
*/
void
isc_nm_attach(isc_nm_t *mgr, isc_nm_t **dst);
void
isc_nm_detach(isc_nm_t **mgr0);
/*%<
* Attach/detach a network manager. When all references have been
* released, the network manager is shut down, freeing all resources.
* Destroy is working the same way as detach, but it actively waits
* for all other references to be gone.
*/
/* Return thread ID of current thread, or ISC_NETMGR_TID_UNKNOWN */
int
isc_nm_tid(void);
void
isc_nmsocket_close(isc_nmsocket_t **sockp);
/*%<
* isc_nmsocket_close() detaches a listening socket that was
* created by isc_nm_listenudp(), isc_nm_listentcp(), or
* isc_nm_listentcpdns(). Once there are no remaining child
* sockets with active handles, the socket will be closed.
*/
#ifdef NETMGR_TRACE
#define isc_nmhandle_attach(handle, dest) \
isc__nmhandle_attach(handle, dest, __FILE__, __LINE__, __func__)
#define isc_nmhandle_detach(handlep) \
isc__nmhandle_detach(handlep, __FILE__, __LINE__, __func__)
#define FLARG , const char *file, unsigned int line, const char *func
#else
#define isc_nmhandle_attach(handle, dest) isc__nmhandle_attach(handle, dest)
#define isc_nmhandle_detach(handlep) isc__nmhandle_detach(handlep)
#define FLARG
#endif
void
isc__nmhandle_attach(isc_nmhandle_t *handle, isc_nmhandle_t **dest FLARG);
void
isc__nmhandle_detach(isc_nmhandle_t **handlep FLARG);
/*%<
* Increment/decrement the reference counter in a netmgr handle,
* but (unlike the attach/detach functions) do not change the pointer
* value. If reference counters drop to zero, the handle can be
* marked inactive, possibly triggering deletion of its associated
* socket.
*
* (This will be used to prevent a client from being cleaned up when
* it's passed to an isc_task event handler. The libuv code would not
* otherwise know that the handle was in use and might free it, along
* with the client.)
*/
#undef FLARG
void *
isc_nmhandle_getdata(isc_nmhandle_t *handle);
void *
isc_nmhandle_getextra(isc_nmhandle_t *handle);
bool
isc_nmhandle_is_stream(isc_nmhandle_t *handle);
void
isc_nmhandle_setdata(isc_nmhandle_t *handle, void *arg,
isc_nm_opaquecb_t doreset, isc_nm_opaquecb_t dofree);
/*%<
* isc_nmhandle_t has a void* opaque field (for example, ns_client_t).
* We reuse handle and `opaque` can also be reused between calls.
* This function sets this field and two callbacks:
* - doreset resets the `opaque` to initial state
* - dofree frees everything associated with `opaque`
*/
void
isc_nmhandle_settimeout(isc_nmhandle_t *handle, uint32_t timeout);
void
isc_nmhandle_cleartimeout(isc_nmhandle_t *handle);
/*%<
* Set/clear the read/recv timeout for the socket connected to 'handle'
* to 'timeout' (in milliseconds), and reset the timer.
*
* When this is called on a 'wrapper' socket handle (for example,
* a TCPDNS socket wrapping a TCP connection), the timer is set for
* both socket layers.
*/
void
isc_nmhandle_keepalive(isc_nmhandle_t *handle, bool value);
/*%<
* Enable/disable keepalive on this connection by setting it to 'value'.
*
* When keepalive is active, we switch to using the keepalive timeout
* to determine when to close a connection, rather than the idle timeout.
*
* This applies only to TCP-based DNS connections (i.e., TCPDNS).
* On other types of connection it has no effect.
*/
isc_sockaddr_t
isc_nmhandle_peeraddr(isc_nmhandle_t *handle);
/*%<
* Return the peer address for the given handle.
*/
isc_sockaddr_t
isc_nmhandle_localaddr(isc_nmhandle_t *handle);
/*%<
* Return the local address for the given handle.
*/
isc_nm_t *
isc_nmhandle_netmgr(isc_nmhandle_t *handle);
/*%<
* Return a pointer to the netmgr object for the given handle.
*/
isc_result_t
isc_nm_listenudp(isc_nm_t *mgr, isc_sockaddr_t *iface, isc_nm_recv_cb_t cb,
void *cbarg, size_t extrasize, isc_nmsocket_t **sockp);
/*%<
* Start listening for UDP packets on interface 'iface' using net manager
* 'mgr'.
*
* On success, 'sockp' will be updated to contain a new listening UDP socket.
*
* When a packet is received on the socket, 'cb' will be called with 'cbarg'
* as its argument.
*
* When handles are allocated for the socket, 'extrasize' additional bytes
* can be allocated along with the handle for an associated object, which
* can then be freed automatically when the handle is destroyed.
*/
void
isc_nm_udpconnect(isc_nm_t *mgr, isc_sockaddr_t *local, isc_sockaddr_t *peer,
isc_nm_cb_t cb, void *cbarg, unsigned int timeout,
size_t extrahandlesize);
/*%<
* Open a UDP socket, bind to 'local' and connect to 'peer', and
* immediately call 'cb' with a handle so that the caller can begin
* sending packets over UDP.
*
* When handles are allocated for the socket, 'extrasize' additional bytes
* can be allocated along with the handle for an associated object, which
* can then be freed automatically when the handle is destroyed.
*
* 'timeout' specifies the timeout interval in milliseconds.
*
* The connected socket can only be accessed via the handle passed to
* 'cb'.
*/
void
isc_nm_stoplistening(isc_nmsocket_t *sock);
/*%<
* Stop listening on socket 'sock'.
*/
void
isc_nm_pause(isc_nm_t *mgr);
/*%<
* Pause all processing, equivalent to taskmgr exclusive tasks.
* It won't return until all workers have been paused.
*/
void
isc_nm_resume(isc_nm_t *mgr);
/*%<
* Resume paused processing. It will return immediately after signalling
* workers to resume.
*/
void
isc_nm_read(isc_nmhandle_t *handle, isc_nm_recv_cb_t cb, void *cbarg);
/*
* Begin (or continue) reading on the socket associated with 'handle', and
* update its recv callback to 'cb', which will be called as soon as there
* is data to process.
*/
void
isc_nm_pauseread(isc_nmhandle_t *handle);
/*%<
* Pause reading on this handle's socket, but remember the callback.
*
* Requires:
* \li 'handle' is a valid netmgr handle.
*/
void
isc_nm_cancelread(isc_nmhandle_t *handle);
/*%<
* Cancel reading on a connected socket. Calls the read/recv callback on
* active handles with a result code of ISC_R_CANCELED.
*
* Requires:
* \li 'sock' is a valid netmgr socket
* \li ...for which a read/recv callback has been defined.
*/
void
isc_nm_resumeread(isc_nmhandle_t *handle);
/*%<
* Resume reading on the handle's socket.
*
* Requires:
* \li 'handle' is a valid netmgr handle.
* \li ...for a socket with a defined read/recv callback.
*/
void
isc_nm_send(isc_nmhandle_t *handle, isc_region_t *region, isc_nm_cb_t cb,
void *cbarg);
/*%<
* Send the data in 'region' via 'handle'. Afterward, the callback 'cb' is
* called with the argument 'cbarg'.
*
* 'region' is not copied; it has to be allocated beforehand and freed
* in 'cb'.
*/
isc_result_t
isc_nm_listentcp(isc_nm_t *mgr, isc_sockaddr_t *iface,
isc_nm_accept_cb_t accept_cb, void *accept_cbarg,
size_t extrahandlesize, int backlog, isc_quota_t *quota,
isc_nmsocket_t **sockp);
/*%<
* Start listening for raw messages over the TCP interface 'iface', using
* net manager 'mgr'.
*
* On success, 'sockp' will be updated to contain a new listening TCP
* socket.
*
* When connection is accepted on the socket, 'accept_cb' will be called with
* 'accept_cbarg' as its argument. The callback is expected to start a read.
*
* When handles are allocated for the socket, 'extrasize' additional bytes
* will be allocated along with the handle for an associated object.
*
* If 'quota' is not NULL, then the socket is attached to the specified
* quota. This allows us to enforce TCP client quota limits.
*
*/
void
isc_nm_tcpconnect(isc_nm_t *mgr, isc_sockaddr_t *local, isc_sockaddr_t *peer,
isc_nm_cb_t cb, void *cbarg, unsigned int timeout,
size_t extrahandlesize);
/*%<
* Create a socket using netmgr 'mgr', bind it to the address 'local',
* and connect it to the address 'peer'.
*
* When the connection is complete or has timed out, call 'cb' with
* argument 'cbarg'. Allocate 'extrahandlesize' additional bytes along
* with the handle to use for an associated object.
*
* 'timeout' specifies the timeout interval in milliseconds.
*
* The connected socket can only be accessed via the handle passed to
* 'cb'.
*/
isc_result_t
isc_nm_listentcpdns(isc_nm_t *mgr, isc_sockaddr_t *iface,
isc_nm_recv_cb_t recv_cb, void *recv_cbarg,
isc_nm_accept_cb_t accept_cb, void *accept_cbarg,
size_t extrahandlesize, int backlog, isc_quota_t *quota,
isc_nmsocket_t **sockp);
/*%<
* Start listening for DNS messages over the TCP interface 'iface', using
* net manager 'mgr'.
*
* On success, 'sockp' will be updated to contain a new listening TCPDNS
* socket. This is a wrapper around a raw TCP socket, which sends and
* receives DNS messages via that socket. It handles message buffering
* and pipelining, and automatically prepends messages with a two-byte
* length field.
*
* When a complete DNS message is received on the socket, 'cb' will be
* called with 'cbarg' as its argument.
*
* When a new TCPDNS connection is accepted, 'accept_cb' will be called
* with 'accept_cbarg' as its argument.
*
* When handles are allocated for the socket, 'extrasize' additional bytes
* will be allocated along with the handle for an associated object
* (typically ns_client).
*
* 'quota' is passed to isc_nm_listentcp() when opening the raw TCP socket.
*/
void
isc_nm_tcpdns_sequential(isc_nmhandle_t *handle);
/*%<
* Disable pipelining on this connection. Each DNS packet will be only
* processed after the previous completes.
*
* The socket must be unpaused after the query is processed. This is done
* the response is sent, or if we're dropping the query, it will be done
* when a handle is fully dereferenced by calling the socket's
* closehandle_cb callback.
*
* Note: This can only be run while a message is being processed; if it is
* run before any messages are read, no messages will be read.
*
* Also note: once this has been set, it cannot be reversed for a given
* connection.
*/
void
isc_nm_tcpdns_keepalive(isc_nmhandle_t *handle, bool value);
/*%<
* Enable/disable keepalive on this connection by setting it to 'value'.
*
* When keepalive is active, we switch to using the keepalive timeout
* to determine when to close a connection, rather than the idle timeout.
*/
void
isc_nm_settimeouts(isc_nm_t *mgr, uint32_t init, uint32_t idle,
uint32_t keepalive, uint32_t advertised);
/*%<
* Sets the initial, idle, and keepalive timeout values (in milliseconds) to use
* for TCP connections, and the timeout value to advertise in responses using
* the EDNS TCP Keepalive option (which should ordinarily be the same
* as 'keepalive'), in milliseconds.
*
* Requires:
* \li 'mgr' is a valid netmgr.
*/
void
isc_nm_gettimeouts(isc_nm_t *mgr, uint32_t *initial, uint32_t *idle,
uint32_t *keepalive, uint32_t *advertised);
/*%<
* Gets the initial, idle, keepalive, or advertised timeout values,
* in milliseconds.
*
* Any integer pointer parameter not set to NULL will be updated to
* contain the corresponding timeout value.
*
* Requires:
* \li 'mgr' is a valid netmgr.
*/
void
isc_nm_maxudp(isc_nm_t *mgr, uint32_t maxudp);
/*%<
* Simulate a broken firewall that blocks UDP messages larger than a given
* size.
*/
void
isc_nm_setstats(isc_nm_t *mgr, isc_stats_t *stats);
/*%<
* Set a socket statistics counter set 'stats' for 'mgr'.
*
* Requires:
*\li 'mgr' is valid and doesn't have stats already set.
*
*\li stats is a valid set of statistics counters supporting the
* full range of socket-related stats counter numbers.
*/
void
isc_nm_tcpdnsconnect(isc_nm_t *mgr, isc_sockaddr_t *local, isc_sockaddr_t *peer,
isc_nm_cb_t cb, void *cbarg, unsigned int timeout,
size_t extrahandlesize);
/*%<
* Establish a DNS client connection via a TCP connection, bound to
* the address 'local' and connected to the address 'peer'.
*
* When the connection is complete or has timed out, call 'cb' with
* argument 'cbarg'. Allocate 'extrahandlesize' additional bytes along
* with the handle to use for an associated object.
*
* 'timeout' specifies the timeout interval in milliseconds.
*
* The connected socket can only be accessed via the handle passed to
* 'cb'.
*/
#define ISC_NM_TASK_SLOW_OFFSET -2
#define ISC_NM_TASK_SLOW(i) (ISC_NM_TASK_SLOW_OFFSET - 1 - i)
void
isc_nm_task_enqueue(isc_nm_t *mgr, isc_task_t *task, int threadid);
/*%<
* Enqueue the 'task' onto the netmgr ievents queue.
*
* Requires:
* \li 'mgr' is a valid netmgr object
* \li 'task' is a valid task
* \li 'threadid' is either the preferred netmgr tid or -1, in which case
* tid will be picked randomly. The threadid is capped (by modulo) to
* maximum number of 'workers' as specifed in isc_nm_start()
*/
void
isc_nm_work_offload(isc_nm_t *mgr, isc_nm_workcb_t work_cb,
isc_nm_after_workcb_t after_work_cb, void *data);
/*%<
* Schedules a job to be handled by the libuv thread pool (see uv_work_t).
* The function specified in `work_cb` will be run by a thread in the
* thread pool; when complete, the `after_work_cb` function will run.
*
* Requires:
* \li 'mgr' is a valid netmgr object.
* \li We are currently running in a network manager thread.
*/
void
isc__nm_force_tid(int tid);
/*%<
* Force the thread ID to 'tid'. This is STRICTLY for use in unit
* tests and should not be used in any production code.
*/