1 /* 2 * svc.h, Server-side remote procedure call interface. 3 * 4 * Copyright (C) 2012-2022 Free Software Foundation, Inc. 5 * This file is part of the GNU C Library. 6 * 7 * The GNU C Library is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * The GNU C Library is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with the GNU C Library; if not, see 19 * <https://www.gnu.org/licenses/>. 20 * 21 * Copyright (c) 2010, Oracle America, Inc. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions are 25 * met: 26 * 27 * * Redistributions of source code must retain the above copyright 28 * notice, this list of conditions and the following disclaimer. 29 * * Redistributions in binary form must reproduce the above 30 * copyright notice, this list of conditions and the following 31 * disclaimer in the documentation and/or other materials 32 * provided with the distribution. 33 * * Neither the name of the "Oracle America, Inc." nor the names of its 34 * contributors may be used to endorse or promote products derived 35 * from this software without specific prior written permission. 36 * 37 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 38 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 39 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 40 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 41 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 42 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 43 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 44 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 45 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 46 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 47 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 48 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 49 */ 50 51 #ifndef _RPC_SVC_H 52 #define _RPC_SVC_H 1 53 54 #include <features.h> 55 #include <rpc/rpc_msg.h> 56 57 __BEGIN_DECLS 58 59 /* 60 * This interface must manage two items concerning remote procedure calling: 61 * 62 * 1) An arbitrary number of transport connections upon which rpc requests 63 * are received. The two most notable transports are TCP and UDP; they are 64 * created and registered by routines in svc_tcp.c and svc_udp.c, respectively; 65 * they in turn call xprt_register and xprt_unregister. 66 * 67 * 2) An arbitrary number of locally registered services. Services are 68 * described by the following four data: program number, version number, 69 * "service dispatch" function, a transport handle, and a boolean that 70 * indicates whether or not the exported program should be registered with a 71 * local binder service; if true the program's number and version and the 72 * port number from the transport handle are registered with the binder. 73 * These data are registered with the rpc svc system via svc_register. 74 * 75 * A service's dispatch function is called whenever an rpc request comes in 76 * on a transport. The request's program and version numbers must match 77 * those of the registered service. The dispatch function is passed two 78 * parameters, struct svc_req * and SVCXPRT *, defined below. 79 */ 80 81 enum xprt_stat { 82 XPRT_DIED, 83 XPRT_MOREREQS, 84 XPRT_IDLE 85 }; 86 87 /* 88 * Server side transport handle 89 */ 90 typedef struct SVCXPRT SVCXPRT; 91 struct SVCXPRT { 92 int xp_sock; 93 u_short xp_port; /* associated port number */ 94 const struct xp_ops { 95 bool_t (*xp_recv) (SVCXPRT *__xprt, struct rpc_msg *__msg); 96 /* receive incoming requests */ 97 enum xprt_stat (*xp_stat) (SVCXPRT *__xprt); 98 /* get transport status */ 99 bool_t (*xp_getargs) (SVCXPRT *__xprt, xdrproc_t __xdr_args, 100 caddr_t __args_ptr); /* get arguments */ 101 bool_t (*xp_reply) (SVCXPRT *__xprt, struct rpc_msg *__msg); 102 /* send reply */ 103 bool_t (*xp_freeargs) (SVCXPRT *__xprt, xdrproc_t __xdr_args, 104 caddr_t __args_ptr); 105 /* free mem allocated for args */ 106 void (*xp_destroy) (SVCXPRT *__xprt); 107 /* destroy this struct */ 108 } *xp_ops; 109 int xp_addrlen; /* length of remote address */ 110 struct sockaddr_in xp_raddr; /* remote address */ 111 struct opaque_auth xp_verf; /* raw response verifier */ 112 caddr_t xp_p1; /* private */ 113 caddr_t xp_p2; /* private */ 114 char xp_pad [256]; /* padding, internal use */ 115 }; 116 117 /* 118 * Approved way of getting address of caller 119 */ 120 #define svc_getcaller(x) (&(x)->xp_raddr) 121 122 /* 123 * Operations defined on an SVCXPRT handle 124 * 125 * SVCXPRT *xprt; 126 * struct rpc_msg *msg; 127 * xdrproc_t xargs; 128 * caddr_t argsp; 129 */ 130 #define SVC_RECV(xprt, msg) \ 131 (*(xprt)->xp_ops->xp_recv)((xprt), (msg)) 132 #define svc_recv(xprt, msg) \ 133 (*(xprt)->xp_ops->xp_recv)((xprt), (msg)) 134 135 #define SVC_STAT(xprt) \ 136 (*(xprt)->xp_ops->xp_stat)(xprt) 137 #define svc_stat(xprt) \ 138 (*(xprt)->xp_ops->xp_stat)(xprt) 139 140 #define SVC_GETARGS(xprt, xargs, argsp) \ 141 (*(xprt)->xp_ops->xp_getargs)((xprt), (xargs), (argsp)) 142 #define svc_getargs(xprt, xargs, argsp) \ 143 (*(xprt)->xp_ops->xp_getargs)((xprt), (xargs), (argsp)) 144 145 #define SVC_REPLY(xprt, msg) \ 146 (*(xprt)->xp_ops->xp_reply) ((xprt), (msg)) 147 #define svc_reply(xprt, msg) \ 148 (*(xprt)->xp_ops->xp_reply) ((xprt), (msg)) 149 150 #define SVC_FREEARGS(xprt, xargs, argsp) \ 151 (*(xprt)->xp_ops->xp_freeargs)((xprt), (xargs), (argsp)) 152 #define svc_freeargs(xprt, xargs, argsp) \ 153 (*(xprt)->xp_ops->xp_freeargs)((xprt), (xargs), (argsp)) 154 155 #define SVC_DESTROY(xprt) \ 156 (*(xprt)->xp_ops->xp_destroy)(xprt) 157 #define svc_destroy(xprt) \ 158 (*(xprt)->xp_ops->xp_destroy)(xprt) 159 160 161 /* 162 * Service request 163 */ 164 struct svc_req { 165 rpcprog_t rq_prog; /* service program number */ 166 rpcvers_t rq_vers; /* service protocol version */ 167 rpcproc_t rq_proc; /* the desired procedure */ 168 struct opaque_auth rq_cred; /* raw creds from the wire */ 169 caddr_t rq_clntcred; /* read only cooked cred */ 170 SVCXPRT *rq_xprt; /* associated transport */ 171 }; 172 173 #ifndef __DISPATCH_FN_T 174 #define __DISPATCH_FN_T 175 typedef void (*__dispatch_fn_t) (struct svc_req*, SVCXPRT*); 176 #endif 177 178 /* 179 * Service registration 180 * 181 * svc_register(xprt, prog, vers, dispatch, protocol) 182 * SVCXPRT *xprt; 183 * rpcprog_t prog; 184 * rpcvers_t vers; 185 * void (*dispatch)(struct svc_req*, SVCXPRT*); 186 * rpcprot_t protocol; like TCP or UDP, zero means do not register 187 */ 188 extern bool_t svc_register (SVCXPRT *__xprt, rpcprog_t __prog, 189 rpcvers_t __vers, __dispatch_fn_t __dispatch, 190 rpcprot_t __protocol) __THROW; 191 192 /* 193 * Service un-registration 194 * 195 * svc_unregister(prog, vers) 196 * rpcprog_t prog; 197 * rpcvers_t vers; 198 */ 199 extern void svc_unregister (rpcprog_t __prog, rpcvers_t __vers) __THROW; 200 201 /* 202 * Transport registration. 203 * 204 * xprt_register(xprt) 205 * SVCXPRT *xprt; 206 */ 207 extern void xprt_register (SVCXPRT *__xprt) __THROW; 208 209 /* 210 * Transport un-register 211 * 212 * xprt_unregister(xprt) 213 * SVCXPRT *xprt; 214 */ 215 extern void xprt_unregister (SVCXPRT *__xprt) __THROW; 216 217 218 /* 219 * When the service routine is called, it must first check to see if it 220 * knows about the procedure; if not, it should call svcerr_noproc 221 * and return. If so, it should deserialize its arguments via 222 * SVC_GETARGS (defined above). If the deserialization does not work, 223 * svcerr_decode should be called followed by a return. Successful 224 * decoding of the arguments should be followed the execution of the 225 * procedure's code and a call to svc_sendreply. 226 * 227 * Also, if the service refuses to execute the procedure due to too- 228 * weak authentication parameters, svcerr_weakauth should be called. 229 * Note: do not confuse access-control failure with weak authentication! 230 * 231 * NB: In pure implementations of rpc, the caller always waits for a reply 232 * msg. This message is sent when svc_sendreply is called. 233 * Therefore pure service implementations should always call 234 * svc_sendreply even if the function logically returns void; use 235 * xdr.h - xdr_void for the xdr routine. HOWEVER, tcp based rpc allows 236 * for the abuse of pure rpc via batched calling or pipelining. In the 237 * case of a batched call, svc_sendreply should NOT be called since 238 * this would send a return message, which is what batching tries to avoid. 239 * It is the service/protocol writer's responsibility to know which calls are 240 * batched and which are not. Warning: responding to batch calls may 241 * deadlock the caller and server processes! 242 */ 243 244 extern bool_t svc_sendreply (SVCXPRT *__xprt, xdrproc_t __xdr_results, 245 caddr_t __xdr_location) __THROW; 246 247 extern void svcerr_decode (SVCXPRT *__xprt) __THROW; 248 249 extern void svcerr_weakauth (SVCXPRT *__xprt) __THROW; 250 251 extern void svcerr_noproc (SVCXPRT *__xprt) __THROW; 252 253 extern void svcerr_progvers (SVCXPRT *__xprt, rpcvers_t __low_vers, 254 rpcvers_t __high_vers) __THROW; 255 256 extern void svcerr_auth (SVCXPRT *__xprt, enum auth_stat __why) __THROW; 257 258 extern void svcerr_noprog (SVCXPRT *__xprt) __THROW; 259 260 extern void svcerr_systemerr (SVCXPRT *__xprt) __THROW; 261 262 /* 263 * Lowest level dispatching -OR- who owns this process anyway. 264 * Somebody has to wait for incoming requests and then call the correct 265 * service routine. The routine svc_run does infinite waiting; i.e., 266 * svc_run never returns. 267 * Since another (coexistent) package may wish to selectively wait for 268 * incoming calls or other events outside of the rpc architecture, the 269 * routine svc_getreq is provided. It must be passed readfds, the 270 * "in-place" results of a select system call (see select, section 2). 271 */ 272 273 /* 274 * Global keeper of rpc service descriptors in use 275 * dynamic; must be inspected before each call to select 276 */ 277 278 extern struct pollfd *svc_pollfd; 279 extern int svc_max_pollfd; 280 extern fd_set svc_fdset; 281 #define svc_fds svc_fdset.fds_bits[0] /* compatibility */ 282 283 /* 284 * a small program implemented by the svc_rpc implementation itself; 285 * also see clnt.h for protocol numbers. 286 */ 287 extern void svc_getreq (int __rdfds) __THROW; 288 extern void svc_getreq_common (const int __fd) __THROW; 289 extern void svc_getreqset (fd_set *__readfds) __THROW; 290 extern void svc_getreq_poll (struct pollfd *, const int) __THROW; 291 extern void svc_exit (void) __THROW; 292 extern void svc_run (void) __THROW; 293 294 /* 295 * Socket to use on svcxxx_create call to get default socket 296 */ 297 #define RPC_ANYSOCK -1 298 299 /* 300 * These are the existing service side transport implementations 301 */ 302 303 /* 304 * Memory based rpc for testing and timing. 305 */ 306 extern SVCXPRT *svcraw_create (void) __THROW; 307 308 /* 309 * Udp based rpc. 310 */ 311 extern SVCXPRT *svcudp_create (int __sock) __THROW; 312 extern SVCXPRT *svcudp_bufcreate (int __sock, u_int __sendsz, u_int __recvsz) 313 __THROW; 314 315 /* 316 * Tcp based rpc. 317 */ 318 extern SVCXPRT *svctcp_create (int __sock, u_int __sendsize, u_int __recvsize) 319 __THROW; 320 321 /* 322 * FD based rpc. 323 */ 324 extern SVCXPRT *svcfd_create (int __sock, u_int __sendsize, u_int __recvsize) 325 __THROW; 326 327 /* 328 * Unix based rpc. 329 */ 330 extern SVCXPRT *svcunix_create (int __sock, u_int __sendsize, u_int __recvsize, 331 char *__path) __THROW; 332 333 334 __END_DECLS 335 336 #endif /* rpc/svc.h */ 337