/* * svc.h, Server-side remote procedure call interface. * * Copyright (C) 2012-2020 Free Software Foundation, Inc. * This file is part of the GNU C Library. * * The GNU C Library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * The GNU C Library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with the GNU C Library; if not, see * <https://www.gnu.org/licenses/>. * * Copyright (c) 2010, Oracle America, Inc. * * 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 "Oracle America, Inc." 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. */ #ifndef _RPC_SVC_H #define _RPC_SVC_H 1 #include <features.h> #include <rpc/rpc_msg.h> __BEGIN_DECLS /* * This interface must manage two items concerning remote procedure calling: * * 1) An arbitrary number of transport connections upon which rpc requests * are received. The two most notable transports are TCP and UDP; they are * created and registered by routines in svc_tcp.c and svc_udp.c, respectively; * they in turn call xprt_register and xprt_unregister. * * 2) An arbitrary number of locally registered services. Services are * described by the following four data: program number, version number, * "service dispatch" function, a transport handle, and a boolean that * indicates whether or not the exported program should be registered with a * local binder service; if true the program's number and version and the * port number from the transport handle are registered with the binder. * These data are registered with the rpc svc system via svc_register. * * A service's dispatch function is called whenever an rpc request comes in * on a transport. The request's program and version numbers must match * those of the registered service. The dispatch function is passed two * parameters, struct svc_req * and SVCXPRT *, defined below. */ enum xprt_stat { XPRT_DIED, XPRT_MOREREQS, XPRT_IDLE }; /* * Server side transport handle */ typedef struct SVCXPRT SVCXPRT; struct SVCXPRT { int xp_sock; u_short xp_port; /* associated port number */ const struct xp_ops { bool_t (*xp_recv) (SVCXPRT *__xprt, struct rpc_msg *__msg); /* receive incoming requests */ enum xprt_stat (*xp_stat) (SVCXPRT *__xprt); /* get transport status */ bool_t (*xp_getargs) (SVCXPRT *__xprt, xdrproc_t __xdr_args, caddr_t __args_ptr); /* get arguments */ bool_t (*xp_reply) (SVCXPRT *__xprt, struct rpc_msg *__msg); /* send reply */ bool_t (*xp_freeargs) (SVCXPRT *__xprt, xdrproc_t __xdr_args, caddr_t __args_ptr); /* free mem allocated for args */ void (*xp_destroy) (SVCXPRT *__xprt); /* destroy this struct */ } *xp_ops; int xp_addrlen; /* length of remote address */ struct sockaddr_in xp_raddr; /* remote address */ struct opaque_auth xp_verf; /* raw response verifier */ caddr_t xp_p1; /* private */ caddr_t xp_p2; /* private */ char xp_pad [256]; /* padding, internal use */ }; /* * Approved way of getting address of caller */ #define svc_getcaller(x) (&(x)->xp_raddr) /* * Operations defined on an SVCXPRT handle * * SVCXPRT *xprt; * struct rpc_msg *msg; * xdrproc_t xargs; * caddr_t argsp; */ #define SVC_RECV(xprt, msg) \ (*(xprt)->xp_ops->xp_recv)((xprt), (msg)) #define svc_recv(xprt, msg) \ (*(xprt)->xp_ops->xp_recv)((xprt), (msg)) #define SVC_STAT(xprt) \ (*(xprt)->xp_ops->xp_stat)(xprt) #define svc_stat(xprt) \ (*(xprt)->xp_ops->xp_stat)(xprt) #define SVC_GETARGS(xprt, xargs, argsp) \ (*(xprt)->xp_ops->xp_getargs)((xprt), (xargs), (argsp)) #define svc_getargs(xprt, xargs, argsp) \ (*(xprt)->xp_ops->xp_getargs)((xprt), (xargs), (argsp)) #define SVC_REPLY(xprt, msg) \ (*(xprt)->xp_ops->xp_reply) ((xprt), (msg)) #define svc_reply(xprt, msg) \ (*(xprt)->xp_ops->xp_reply) ((xprt), (msg)) #define SVC_FREEARGS(xprt, xargs, argsp) \ (*(xprt)->xp_ops->xp_freeargs)((xprt), (xargs), (argsp)) #define svc_freeargs(xprt, xargs, argsp) \ (*(xprt)->xp_ops->xp_freeargs)((xprt), (xargs), (argsp)) #define SVC_DESTROY(xprt) \ (*(xprt)->xp_ops->xp_destroy)(xprt) #define svc_destroy(xprt) \ (*(xprt)->xp_ops->xp_destroy)(xprt) /* * Service request */ struct svc_req { rpcprog_t rq_prog; /* service program number */ rpcvers_t rq_vers; /* service protocol version */ rpcproc_t rq_proc; /* the desired procedure */ struct opaque_auth rq_cred; /* raw creds from the wire */ caddr_t rq_clntcred; /* read only cooked cred */ SVCXPRT *rq_xprt; /* associated transport */ }; #ifndef __DISPATCH_FN_T #define __DISPATCH_FN_T typedef void (*__dispatch_fn_t) (struct svc_req*, SVCXPRT*); #endif /* * Service registration * * svc_register(xprt, prog, vers, dispatch, protocol) * SVCXPRT *xprt; * rpcprog_t prog; * rpcvers_t vers; * void (*dispatch)(struct svc_req*, SVCXPRT*); * rpcprot_t protocol; like TCP or UDP, zero means do not register */ extern bool_t svc_register (SVCXPRT *__xprt, rpcprog_t __prog, rpcvers_t __vers, __dispatch_fn_t __dispatch, rpcprot_t __protocol) __THROW; /* * Service un-registration * * svc_unregister(prog, vers) * rpcprog_t prog; * rpcvers_t vers; */ extern void svc_unregister (rpcprog_t __prog, rpcvers_t __vers) __THROW; /* * Transport registration. * * xprt_register(xprt) * SVCXPRT *xprt; */ extern void xprt_register (SVCXPRT *__xprt) __THROW; /* * Transport un-register * * xprt_unregister(xprt) * SVCXPRT *xprt; */ extern void xprt_unregister (SVCXPRT *__xprt) __THROW; /* * When the service routine is called, it must first check to see if it * knows about the procedure; if not, it should call svcerr_noproc * and return. If so, it should deserialize its arguments via * SVC_GETARGS (defined above). If the deserialization does not work, * svcerr_decode should be called followed by a return. Successful * decoding of the arguments should be followed the execution of the * procedure's code and a call to svc_sendreply. * * Also, if the service refuses to execute the procedure due to too- * weak authentication parameters, svcerr_weakauth should be called. * Note: do not confuse access-control failure with weak authentication! * * NB: In pure implementations of rpc, the caller always waits for a reply * msg. This message is sent when svc_sendreply is called. * Therefore pure service implementations should always call * svc_sendreply even if the function logically returns void; use * xdr.h - xdr_void for the xdr routine. HOWEVER, tcp based rpc allows * for the abuse of pure rpc via batched calling or pipelining. In the * case of a batched call, svc_sendreply should NOT be called since * this would send a return message, which is what batching tries to avoid. * It is the service/protocol writer's responsibility to know which calls are * batched and which are not. Warning: responding to batch calls may * deadlock the caller and server processes! */ extern bool_t svc_sendreply (SVCXPRT *__xprt, xdrproc_t __xdr_results, caddr_t __xdr_location) __THROW; extern void svcerr_decode (SVCXPRT *__xprt) __THROW; extern void svcerr_weakauth (SVCXPRT *__xprt) __THROW; extern void svcerr_noproc (SVCXPRT *__xprt) __THROW; extern void svcerr_progvers (SVCXPRT *__xprt, rpcvers_t __low_vers, rpcvers_t __high_vers) __THROW; extern void svcerr_auth (SVCXPRT *__xprt, enum auth_stat __why) __THROW; extern void svcerr_noprog (SVCXPRT *__xprt) __THROW; extern void svcerr_systemerr (SVCXPRT *__xprt) __THROW; /* * Lowest level dispatching -OR- who owns this process anyway. * Somebody has to wait for incoming requests and then call the correct * service routine. The routine svc_run does infinite waiting; i.e., * svc_run never returns. * Since another (coexistent) package may wish to selectively wait for * incoming calls or other events outside of the rpc architecture, the * routine svc_getreq is provided. It must be passed readfds, the * "in-place" results of a select system call (see select, section 2). */ /* * Global keeper of rpc service descriptors in use * dynamic; must be inspected before each call to select */ extern struct pollfd *svc_pollfd; extern int svc_max_pollfd; extern fd_set svc_fdset; #define svc_fds svc_fdset.fds_bits[0] /* compatibility */ /* * a small program implemented by the svc_rpc implementation itself; * also see clnt.h for protocol numbers. */ extern void svc_getreq (int __rdfds) __THROW; extern void svc_getreq_common (const int __fd) __THROW; extern void svc_getreqset (fd_set *__readfds) __THROW; extern void svc_getreq_poll (struct pollfd *, const int) __THROW; extern void svc_exit (void) __THROW; extern void svc_run (void) __THROW; /* * Socket to use on svcxxx_create call to get default socket */ #define RPC_ANYSOCK -1 /* * These are the existing service side transport implementations */ /* * Memory based rpc for testing and timing. */ extern SVCXPRT *svcraw_create (void) __THROW; /* * Udp based rpc. */ extern SVCXPRT *svcudp_create (int __sock) __THROW; extern SVCXPRT *svcudp_bufcreate (int __sock, u_int __sendsz, u_int __recvsz) __THROW; /* * Tcp based rpc. */ extern SVCXPRT *svctcp_create (int __sock, u_int __sendsize, u_int __recvsize) __THROW; /* * FD based rpc. */ extern SVCXPRT *svcfd_create (int __sock, u_int __sendsize, u_int __recvsize) __THROW; /* * Unix based rpc. */ extern SVCXPRT *svcunix_create (int __sock, u_int __sendsize, u_int __recvsize, char *__path) __THROW; __END_DECLS #endif /* rpc/svc.h */