1 /* $NetBSD: krpc_subr.c,v 1.6 1994/08/12 04:31:51 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1994 Gordon Ross, Adam Glass 5 * Copyright (c) 1992 Regents of the University of California. 6 * All rights reserved. 7 * 8 * This software was developed by the Computer Systems Engineering group 9 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 10 * contributed to Berkeley. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Lawrence Berkeley Laboratory and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * partially based on: 41 * libnetboot/rpc.c 42 * @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL) 43 */ 44 45 #include <sys/param.h> 46 #include <sys/conf.h> 47 #include <sys/ioctl.h> 48 #include <sys/proc.h> 49 #include <sys/mount.h> 50 #include <sys/mbuf.h> 51 #include <sys/socket.h> 52 #include <sys/systm.h> 53 #include <sys/reboot.h> 54 55 #include <net/if.h> 56 #include <netinet/in.h> 57 58 #include <nfs/rpcv2.h> 59 60 /* 61 * Kernel support for Sun RPC 62 * 63 * Used currently for bootstrapping in nfs diskless configurations. 64 * 65 * Note: will not work on variable-sized rpc args/results. 66 * implicit size-limit of an mbuf. 67 */ 68 69 #define PMAPPORT 111 70 #define PMAPPROG 100000 71 #define PMAPVERS 2 72 #define PMAPPROC_GETPORT 3 73 74 /* 75 * Generic RPC headers 76 */ 77 78 struct auth_info { 79 int rp_atype; /* auth type */ 80 u_long rp_alen; /* auth length */ 81 }; 82 83 struct rpc_call { 84 u_long rp_xid; /* request transaction id */ 85 int rp_direction; /* call direction (0) */ 86 u_long rp_rpcvers; /* rpc version (2) */ 87 u_long rp_prog; /* program */ 88 u_long rp_vers; /* version */ 89 u_long rp_proc; /* procedure */ 90 struct auth_info rp_auth; 91 struct auth_info rp_verf; 92 }; 93 94 struct rpc_reply { 95 u_long rp_xid; /* request transaction id */ 96 int rp_direction; /* call direction (1) */ 97 int rp_astatus; /* accept status (0: accepted) */ 98 union { 99 u_long rpu_errno; 100 struct { 101 struct auth_info rp_auth; 102 u_long rp_rstatus; /* reply status */ 103 } rpu_ok; 104 } rp_u; 105 }; 106 107 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 108 109 /* 110 * What is the longest we will wait before re-sending a request? 111 * Note this is also the frequency of "RPC timeout" messages. 112 * The re-send loop count sup linearly to this maximum, so the 113 * first complaint will happen after (1+2+3+4+5)=15 seconds. 114 */ 115 #define MAX_RESEND_DELAY 5 /* seconds */ 116 117 /* 118 * Call portmap to lookup a port number for a particular rpc program 119 * Returns non-zero error on failure. 120 */ 121 int 122 krpc_portmap(sa, prog, vers, portp) 123 struct sockaddr *sa; /* server address */ 124 u_long prog, vers; /* host order */ 125 u_short *portp; /* network order */ 126 { 127 struct sdata { 128 u_long prog; /* call program */ 129 u_long vers; /* call version */ 130 u_long proto; /* call protocol */ 131 u_long port; /* call port (unused) */ 132 } *sdata; 133 struct rdata { 134 u_short pad; 135 u_short port; 136 } *rdata; 137 struct mbuf *m; 138 int error; 139 140 /* The portmapper port is fixed. */ 141 if (prog == PMAPPROG) { 142 *portp = htons(PMAPPORT); 143 return 0; 144 } 145 146 m = m_gethdr(M_WAIT, MT_DATA); 147 if (m == NULL) 148 return ENOBUFS; 149 m->m_len = sizeof(*sdata); 150 m->m_pkthdr.len = m->m_len; 151 sdata = mtod(m, struct sdata *); 152 153 /* Do the RPC to get it. */ 154 sdata->prog = htonl(prog); 155 sdata->vers = htonl(vers); 156 sdata->proto = htonl(IPPROTO_UDP); 157 sdata->port = 0; 158 159 error = krpc_call(sa, PMAPPROG, PMAPVERS, 160 PMAPPROC_GETPORT, &m); 161 if (error) 162 return error; 163 164 rdata = mtod(m, struct rdata *); 165 *portp = rdata->port; 166 167 m_freem(m); 168 return 0; 169 } 170 171 /* 172 * Do a remote procedure call (RPC) and wait for its reply. 173 */ 174 int 175 krpc_call(sa, prog, vers, func, data) 176 struct sockaddr *sa; 177 u_long prog, vers, func; 178 struct mbuf **data; /* input/output */ 179 { 180 struct socket *so; 181 struct sockaddr_in *sin; 182 struct timeval *tv; 183 struct mbuf *m, *nam, *mhead; 184 struct rpc_call *call; 185 struct rpc_reply *reply; 186 struct uio auio; 187 int error, rcvflg, timo, secs, len; 188 static u_long xid = ~0xFF; 189 u_short tport; 190 191 /* 192 * Validate address family. 193 * Sorry, this is INET specific... 194 */ 195 if (sa->sa_family != AF_INET) 196 return (EAFNOSUPPORT); 197 198 /* Free at end if not null. */ 199 nam = mhead = NULL; 200 201 /* 202 * Create socket and set its recieve timeout. 203 */ 204 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0))) 205 goto out; 206 207 m = m_get(M_WAIT, MT_SOOPTS); 208 if (m == NULL) { 209 error = ENOBUFS; 210 goto out; 211 } 212 tv = mtod(m, struct timeval *); 213 m->m_len = sizeof(*tv); 214 tv->tv_sec = 1; 215 tv->tv_usec = 0; 216 if ((error = sosetopt(so, SOL_SOCKET, SO_RCVTIMEO, m))) 217 goto out; 218 219 /* 220 * Bind the local endpoint to a reserved port, 221 * because some NFS servers refuse requests from 222 * non-reserved (non-privileged) ports. 223 */ 224 m = m_getclr(M_WAIT, MT_SONAME); 225 sin = mtod(m, struct sockaddr_in *); 226 sin->sin_len = m->m_len = sizeof(*sin); 227 sin->sin_family = AF_INET; 228 sin->sin_addr.s_addr = INADDR_ANY; 229 tport = IPPORT_RESERVED; 230 do { 231 tport--; 232 sin->sin_port = htons(tport); 233 error = sobind(so, m); 234 } while (error == EADDRINUSE && 235 tport > IPPORT_RESERVED / 2); 236 m_freem(m); 237 if (error) { 238 printf("bind failed\n"); 239 goto out; 240 } 241 242 /* 243 * Setup socket address for the server. 244 */ 245 nam = m_get(M_WAIT, MT_SONAME); 246 if (nam == NULL) { 247 error = ENOBUFS; 248 goto out; 249 } 250 sin = mtod(nam, struct sockaddr_in *); 251 bcopy((caddr_t)sa, (caddr_t)sin, (nam->m_len = sa->sa_len)); 252 253 /* 254 * Set the port number that the request will use. 255 */ 256 if ((error = krpc_portmap(sa, prog, vers, &sin->sin_port))) 257 goto out; 258 259 /* 260 * Prepend RPC message header. 261 */ 262 m = *data; 263 *data = NULL; 264 #ifdef DIAGNOSTIC 265 if ((m->m_flags & M_PKTHDR) == 0) 266 panic("krpc_call: send data w/o pkthdr"); 267 if (m->m_pkthdr.len < m->m_len) 268 panic("krpc_call: pkthdr.len not set"); 269 #endif 270 mhead = m_prepend(m, sizeof(*call), M_WAIT); 271 if (mhead == NULL) { 272 error = ENOBUFS; 273 goto out; 274 } 275 mhead->m_pkthdr.len += sizeof(*call); 276 mhead->m_pkthdr.rcvif = NULL; 277 278 /* 279 * Fill in the RPC header 280 */ 281 call = mtod(mhead, struct rpc_call *); 282 bzero((caddr_t)call, sizeof(*call)); 283 call->rp_xid = ++xid; /* no need to put in network order */ 284 /* call->rp_direction = 0; */ 285 call->rp_rpcvers = htonl(2); 286 call->rp_prog = htonl(prog); 287 call->rp_vers = htonl(vers); 288 call->rp_proc = htonl(func); 289 /* call->rp_auth = 0; */ 290 /* call->rp_verf = 0; */ 291 292 /* 293 * Send it, repeatedly, until a reply is received, 294 * but delay each re-send by an increasing amount. 295 * If the delay hits the maximum, start complaining. 296 */ 297 timo = 0; 298 for (;;) { 299 /* Send RPC request (or re-send). */ 300 m = m_copym(mhead, 0, M_COPYALL, M_WAIT); 301 if (m == NULL) { 302 error = ENOBUFS; 303 goto out; 304 } 305 error = sosend(so, nam, NULL, m, NULL, 0); 306 if (error) { 307 printf("krpc_call: sosend: %d\n", error); 308 goto out; 309 } 310 m = NULL; 311 312 /* Determine new timeout. */ 313 if (timo < MAX_RESEND_DELAY) 314 timo++; 315 else 316 printf("RPC timeout for server 0x%x\n", 317 ntohl(sin->sin_addr.s_addr)); 318 319 /* 320 * Wait for up to timo seconds for a reply. 321 * The socket receive timeout was set to 1 second. 322 */ 323 secs = timo; 324 while (secs > 0) { 325 auio.uio_resid = len = 1<<16; 326 rcvflg = 0; 327 error = soreceive(so, NULL, &auio, &m, NULL, &rcvflg); 328 if (error == EWOULDBLOCK) { 329 secs--; 330 continue; 331 } 332 if (error) 333 goto out; 334 len -= auio.uio_resid; 335 336 /* Is the reply complete and the right one? */ 337 if (len < MIN_REPLY_HDR) { 338 m_freem(m); 339 continue; 340 } 341 if (m->m_len < MIN_REPLY_HDR) { 342 m = m_pullup(m, MIN_REPLY_HDR); 343 if (!m) 344 continue; 345 } 346 reply = mtod(m, struct rpc_reply *); 347 if ((reply->rp_direction == htonl(RPC_REPLY)) && 348 (reply->rp_xid == xid)) 349 goto gotreply; /* break two levels */ 350 } /* while secs */ 351 } /* forever send/receive */ 352 353 error = ETIMEDOUT; 354 goto out; 355 356 gotreply: 357 358 /* 359 * Pull as much as we can into first mbuf, to make 360 * result buffer contiguous. Note that if the entire 361 * result won't fit into one mbuf, you're out of luck. 362 * XXX - Should not rely on making the entire reply 363 * contiguous (fix callers instead). -gwr 364 */ 365 #ifdef DIAGNOSTIC 366 if ((m->m_flags & M_PKTHDR) == 0) 367 panic("krpc_call: received pkt w/o header?"); 368 #endif 369 len = m->m_pkthdr.len; 370 if (m->m_len < len) { 371 m = m_pullup(m, len); 372 if (m == NULL) { 373 error = ENOBUFS; 374 goto out; 375 } 376 } 377 reply = mtod(m, struct rpc_reply *); 378 379 /* 380 * Check RPC acceptance and status. 381 */ 382 if (reply->rp_astatus != 0) { 383 error = ntohl(reply->rp_u.rpu_errno); 384 printf("rpc denied, error=%d\n", error); 385 m_freem(m); 386 goto out; 387 } 388 if ((error = ntohl(reply->rp_u.rpu_ok.rp_rstatus)) != 0) { 389 printf("rpc status=%d\n", error); 390 m_freem(m); 391 goto out; 392 } 393 394 /* 395 * Strip RPC header 396 */ 397 len = sizeof(*reply); 398 if (reply->rp_u.rpu_ok.rp_auth.rp_atype != 0) { 399 len += ntohl(reply->rp_u.rpu_ok.rp_auth.rp_alen); 400 len = (len + 3) & ~3; /* XXX? */ 401 } 402 m_adj(m, len); 403 404 /* result */ 405 *data = m; 406 407 out: 408 if (nam) m_freem(nam); 409 if (mhead) m_freem(mhead); 410 soclose(so); 411 return error; 412 } 413