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Edit File: netmgr.h
/* * 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 <isc/mem.h> #include <isc/region.h> #include <isc/result.h> #include <isc/types.h> /* * 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. */