1 /* $NetBSD: svc_dg.c,v 1.4 2000/07/06 03:10:35 christos Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (c) 2009, Sun Microsystems, Inc. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions are met: 11 * - Redistributions of source code must retain the above copyright notice, 12 * this list of conditions and the following disclaimer. 13 * - Redistributions in binary form must reproduce the above copyright notice, 14 * this list of conditions and the following disclaimer in the documentation 15 * and/or other materials provided with the distribution. 16 * - Neither the name of Sun Microsystems, Inc. nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 21 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1986-1991 by Sun Microsystems Inc. 35 */ 36 37 /* 38 * svc_dg.c, Server side for connectionless RPC. 39 */ 40 41 #include <sys/param.h> 42 #include <sys/jail.h> 43 #include <sys/lock.h> 44 #include <sys/kernel.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/mutex.h> 48 #include <sys/proc.h> 49 #include <sys/protosw.h> 50 #include <sys/queue.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/sx.h> 54 #include <sys/systm.h> 55 #include <sys/uio.h> 56 57 #include <net/vnet.h> 58 59 #include <rpc/rpc.h> 60 61 #include <rpc/rpc_com.h> 62 63 static enum xprt_stat svc_dg_stat(SVCXPRT *); 64 static bool_t svc_dg_recv(SVCXPRT *, struct rpc_msg *, 65 struct sockaddr **, struct mbuf **); 66 static bool_t svc_dg_reply(SVCXPRT *, struct rpc_msg *, 67 struct sockaddr *, struct mbuf *, uint32_t *); 68 static void svc_dg_destroy(SVCXPRT *); 69 static bool_t svc_dg_control(SVCXPRT *, const u_int, void *); 70 static int svc_dg_soupcall(struct socket *so, void *arg, int waitflag); 71 72 static const struct xp_ops svc_dg_ops = { 73 .xp_recv = svc_dg_recv, 74 .xp_stat = svc_dg_stat, 75 .xp_reply = svc_dg_reply, 76 .xp_destroy = svc_dg_destroy, 77 .xp_control = svc_dg_control, 78 }; 79 80 /* 81 * Usage: 82 * xprt = svc_dg_create(sock, sendsize, recvsize); 83 * Does other connectionless specific initializations. 84 * Once *xprt is initialized, it is registered. 85 * see (svc.h, xprt_register). If recvsize or sendsize are 0 suitable 86 * system defaults are chosen. 87 * The routines returns NULL if a problem occurred. 88 */ 89 static const char svc_dg_str[] = "svc_dg_create: %s"; 90 static const char svc_dg_err1[] = "could not get transport information"; 91 static const char svc_dg_err2[] = "transport does not support data transfer"; 92 static const char __no_mem_str[] = "out of memory"; 93 94 SVCXPRT * 95 svc_dg_create(SVCPOOL *pool, struct socket *so, size_t sendsize, 96 size_t recvsize) 97 { 98 SVCXPRT *xprt; 99 struct __rpc_sockinfo si; 100 int error; 101 102 if (jailed(curthread->td_ucred)) 103 return (NULL); 104 if (!__rpc_socket2sockinfo(so, &si)) { 105 printf(svc_dg_str, svc_dg_err1); 106 return (NULL); 107 } 108 /* 109 * Find the receive and the send size 110 */ 111 sendsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsize); 112 recvsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsize); 113 if ((sendsize == 0) || (recvsize == 0)) { 114 printf(svc_dg_str, svc_dg_err2); 115 return (NULL); 116 } 117 118 xprt = svc_xprt_alloc(); 119 sx_init(&xprt->xp_lock, "xprt->xp_lock"); 120 xprt->xp_pool = pool; 121 xprt->xp_socket = so; 122 xprt->xp_p1 = NULL; 123 xprt->xp_p2 = NULL; 124 xprt->xp_ops = &svc_dg_ops; 125 126 xprt->xp_ltaddr.ss_len = sizeof(xprt->xp_ltaddr); 127 error = sosockaddr(so, (struct sockaddr *)&xprt->xp_ltaddr); 128 if (error) 129 goto freedata; 130 131 xprt_register(xprt); 132 133 SOCKBUF_LOCK(&so->so_rcv); 134 soupcall_set(so, SO_RCV, svc_dg_soupcall, xprt); 135 SOCKBUF_UNLOCK(&so->so_rcv); 136 137 return (xprt); 138 freedata: 139 (void) printf(svc_dg_str, __no_mem_str); 140 svc_xprt_free(xprt); 141 142 return (NULL); 143 } 144 145 /*ARGSUSED*/ 146 static enum xprt_stat 147 svc_dg_stat(SVCXPRT *xprt) 148 { 149 150 if (soreadable(xprt->xp_socket)) 151 return (XPRT_MOREREQS); 152 153 return (XPRT_IDLE); 154 } 155 156 static bool_t 157 svc_dg_recv(SVCXPRT *xprt, struct rpc_msg *msg, 158 struct sockaddr **addrp, struct mbuf **mp) 159 { 160 struct uio uio; 161 struct sockaddr *raddr; 162 struct mbuf *mreq; 163 XDR xdrs; 164 int error, rcvflag; 165 166 /* 167 * Serialise access to the socket. 168 */ 169 sx_xlock(&xprt->xp_lock); 170 171 /* 172 * The socket upcall calls xprt_active() which will eventually 173 * cause the server to call us here. We attempt to read a 174 * packet from the socket and process it. If the read fails, 175 * we have drained all pending requests so we call 176 * xprt_inactive(). 177 */ 178 uio.uio_resid = 1000000000; 179 uio.uio_td = curthread; 180 mreq = NULL; 181 rcvflag = MSG_DONTWAIT; 182 error = soreceive(xprt->xp_socket, &raddr, &uio, &mreq, NULL, &rcvflag); 183 184 if (error == EWOULDBLOCK) { 185 /* 186 * We must re-test for readability after taking the 187 * lock to protect us in the case where a new packet 188 * arrives on the socket after our call to soreceive 189 * fails with EWOULDBLOCK. The pool lock protects us 190 * from racing the upcall after our soreadable() call 191 * returns false. 192 */ 193 SOCKBUF_LOCK(&xprt->xp_socket->so_rcv); 194 if (!soreadable(xprt->xp_socket)) 195 xprt_inactive_self(xprt); 196 SOCKBUF_UNLOCK(&xprt->xp_socket->so_rcv); 197 sx_xunlock(&xprt->xp_lock); 198 return (FALSE); 199 } 200 201 if (error) { 202 SOCKBUF_LOCK(&xprt->xp_socket->so_rcv); 203 soupcall_clear(xprt->xp_socket, SO_RCV); 204 SOCKBUF_UNLOCK(&xprt->xp_socket->so_rcv); 205 xprt_inactive_self(xprt); 206 sx_xunlock(&xprt->xp_lock); 207 return (FALSE); 208 } 209 210 sx_xunlock(&xprt->xp_lock); 211 212 xdrmbuf_create(&xdrs, mreq, XDR_DECODE); 213 if (! xdr_callmsg(&xdrs, msg)) { 214 XDR_DESTROY(&xdrs); 215 return (FALSE); 216 } 217 218 *addrp = raddr; 219 *mp = xdrmbuf_getall(&xdrs); 220 XDR_DESTROY(&xdrs); 221 222 return (TRUE); 223 } 224 225 static bool_t 226 svc_dg_reply(SVCXPRT *xprt, struct rpc_msg *msg, 227 struct sockaddr *addr, struct mbuf *m, uint32_t *seq) 228 { 229 XDR xdrs; 230 struct mbuf *mrep; 231 bool_t stat = TRUE; 232 int error; 233 234 mrep = m_gethdr(M_WAITOK, MT_DATA); 235 236 xdrmbuf_create(&xdrs, mrep, XDR_ENCODE); 237 238 if (msg->rm_reply.rp_stat == MSG_ACCEPTED && 239 msg->rm_reply.rp_acpt.ar_stat == SUCCESS) { 240 if (!xdr_replymsg(&xdrs, msg)) 241 stat = FALSE; 242 else 243 xdrmbuf_append(&xdrs, m); 244 } else { 245 stat = xdr_replymsg(&xdrs, msg); 246 } 247 248 if (stat) { 249 m_fixhdr(mrep); 250 error = sosend(xprt->xp_socket, addr, NULL, mrep, NULL, 251 0, curthread); 252 if (!error) { 253 stat = TRUE; 254 } 255 } else { 256 m_freem(mrep); 257 } 258 259 XDR_DESTROY(&xdrs); 260 xprt->xp_p2 = NULL; 261 262 return (stat); 263 } 264 265 static void 266 svc_dg_destroy(SVCXPRT *xprt) 267 { 268 269 SOCKBUF_LOCK(&xprt->xp_socket->so_rcv); 270 soupcall_clear(xprt->xp_socket, SO_RCV); 271 SOCKBUF_UNLOCK(&xprt->xp_socket->so_rcv); 272 273 sx_destroy(&xprt->xp_lock); 274 if (xprt->xp_socket) 275 (void)soclose(xprt->xp_socket); 276 277 if (xprt->xp_netid) 278 (void) mem_free(xprt->xp_netid, strlen(xprt->xp_netid) + 1); 279 svc_xprt_free(xprt); 280 } 281 282 static bool_t 283 /*ARGSUSED*/ 284 svc_dg_control(SVCXPRT *xprt, const u_int rq, void *in) 285 { 286 287 return (FALSE); 288 } 289 290 static int 291 svc_dg_soupcall(struct socket *so, void *arg, int waitflag) 292 { 293 SVCXPRT *xprt = (SVCXPRT *) arg; 294 295 xprt_active(xprt); 296 return (SU_OK); 297 } 298