krpc_subr.c revision 88739
1/* $NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd Exp $ */ 2 3/* 4 * Copyright (c) 1995 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/cdefs.h> 46__FBSDID("$FreeBSD: head/sys/nfsclient/krpc_subr.c 88739 2001-12-31 17:45:16Z rwatson $"); 47 48#include <sys/param.h> 49#include <sys/systm.h> 50#include <sys/malloc.h> 51#include <sys/mbuf.h> 52#include <sys/socket.h> 53#include <sys/socketvar.h> 54#include <sys/uio.h> 55 56#include <net/if.h> 57#include <netinet/in.h> 58 59#include <nfs/rpcv2.h> 60#include <nfsclient/krpc.h> 61#include <nfs/xdr_subs.h> 62 63/* 64 * Kernel support for Sun RPC 65 * 66 * Used currently for bootstrapping in nfs diskless configurations. 67 */ 68 69/* 70 * Generic RPC headers 71 */ 72 73struct auth_info { 74 u_int32_t authtype; /* auth type */ 75 u_int32_t authlen; /* auth length */ 76}; 77 78struct auth_unix { 79 int32_t ua_time; 80 int32_t ua_hostname; /* null */ 81 int32_t ua_uid; 82 int32_t ua_gid; 83 int32_t ua_gidlist; /* null */ 84}; 85 86struct rpc_call { 87 u_int32_t rp_xid; /* request transaction id */ 88 int32_t rp_direction; /* call direction (0) */ 89 u_int32_t rp_rpcvers; /* rpc version (2) */ 90 u_int32_t rp_prog; /* program */ 91 u_int32_t rp_vers; /* version */ 92 u_int32_t rp_proc; /* procedure */ 93 struct auth_info rpc_auth; 94 struct auth_unix rpc_unix; 95 struct auth_info rpc_verf; 96}; 97 98struct rpc_reply { 99 u_int32_t rp_xid; /* request transaction id */ 100 int32_t rp_direction; /* call direction (1) */ 101 int32_t rp_astatus; /* accept status (0: accepted) */ 102 union { 103 u_int32_t rpu_errno; 104 struct { 105 struct auth_info rok_auth; 106 u_int32_t rok_status; 107 } rpu_rok; 108 } rp_u; 109}; 110#define rp_errno rp_u.rpu_errno 111#define rp_auth rp_u.rpu_rok.rok_auth 112#define rp_status rp_u.rpu_rok.rok_status 113 114#define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 115 116/* 117 * What is the longest we will wait before re-sending a request? 118 * Note this is also the frequency of "RPC timeout" messages. 119 * The re-send loop count sup linearly to this maximum, so the 120 * first complaint will happen after (1+2+3+4+5)=15 seconds. 121 */ 122#define MAX_RESEND_DELAY 5 /* seconds */ 123 124/* 125 * Call portmap to lookup a port number for a particular rpc program 126 * Returns non-zero error on failure. 127 */ 128int 129krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp, 130 struct thread *td) 131{ 132 struct sdata { 133 u_int32_t prog; /* call program */ 134 u_int32_t vers; /* call version */ 135 u_int32_t proto; /* call protocol */ 136 u_int32_t port; /* call port (unused) */ 137 } *sdata; 138 struct rdata { 139 u_int16_t pad; 140 u_int16_t port; 141 } *rdata; 142 struct mbuf *m; 143 int error; 144 145 /* The portmapper port is fixed. */ 146 if (prog == PMAPPROG) { 147 *portp = htons(PMAPPORT); 148 return 0; 149 } 150 151 m = m_get(M_TRYWAIT, MT_DATA); 152 if (m == NULL) 153 return ENOBUFS; 154 sdata = mtod(m, struct sdata *); 155 m->m_len = sizeof(*sdata); 156 157 /* Do the RPC to get it. */ 158 sdata->prog = txdr_unsigned(prog); 159 sdata->vers = txdr_unsigned(vers); 160 sdata->proto = txdr_unsigned(IPPROTO_UDP); 161 sdata->port = 0; 162 163 sin->sin_port = htons(PMAPPORT); 164 error = krpc_call(sin, PMAPPROG, PMAPVERS, 165 PMAPPROC_GETPORT, &m, NULL, td); 166 if (error) 167 return error; 168 169 if (m->m_len < sizeof(*rdata)) { 170 m = m_pullup(m, sizeof(*rdata)); 171 if (m == NULL) 172 return ENOBUFS; 173 } 174 rdata = mtod(m, struct rdata *); 175 *portp = rdata->port; 176 177 m_freem(m); 178 return 0; 179} 180 181/* 182 * Do a remote procedure call (RPC) and wait for its reply. 183 * If from_p is non-null, then we are doing broadcast, and 184 * the address from whence the response came is saved there. 185 */ 186int 187krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 188 struct mbuf **data, struct sockaddr **from_p, struct thread *td) 189{ 190 struct socket *so; 191 struct sockaddr_in *sin, ssin; 192 struct sockaddr *from; 193 struct mbuf *m, *nam, *mhead; 194 struct rpc_call *call; 195 struct rpc_reply *reply; 196 struct sockopt sopt; 197 struct timeval tv; 198 struct uio auio; 199 int error, rcvflg, timo, secs, len; 200 static u_int32_t xid = ~0xFF; 201 u_int16_t tport; 202 u_int32_t saddr; 203 204 /* 205 * Validate address family. 206 * Sorry, this is INET specific... 207 */ 208 if (sa->sin_family != AF_INET) 209 return (EAFNOSUPPORT); 210 211 /* Free at end if not null. */ 212 nam = mhead = NULL; 213 from = NULL; 214 215 /* 216 * Create socket and set its recieve timeout. 217 */ 218 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, 219 td->td_proc->p_ucred, td))) 220 goto out; 221 222 tv.tv_sec = 1; 223 tv.tv_usec = 0; 224 bzero(&sopt, sizeof sopt); 225 sopt.sopt_level = SOL_SOCKET; 226 sopt.sopt_name = SO_RCVTIMEO; 227 sopt.sopt_val = &tv; 228 sopt.sopt_valsize = sizeof tv; 229 230 if ((error = sosetopt(so, &sopt)) != 0) 231 goto out; 232 233 /* 234 * Enable broadcast if necessary. 235 */ 236 if (from_p) { 237 int on = 1; 238 sopt.sopt_name = SO_BROADCAST; 239 sopt.sopt_val = &on; 240 sopt.sopt_valsize = sizeof on; 241 if ((error = sosetopt(so, &sopt)) != 0) 242 goto out; 243 } 244 245 /* 246 * Bind the local endpoint to a reserved port, 247 * because some NFS servers refuse requests from 248 * non-reserved (non-privileged) ports. 249 */ 250 sin = &ssin; 251 bzero(sin, sizeof *sin); 252 sin->sin_len = sizeof(*sin); 253 sin->sin_family = AF_INET; 254 sin->sin_addr.s_addr = INADDR_ANY; 255 tport = IPPORT_RESERVED; 256 do { 257 tport--; 258 sin->sin_port = htons(tport); 259 error = sobind(so, (struct sockaddr *)sin, td); 260 } while (error == EADDRINUSE && 261 tport > IPPORT_RESERVED / 2); 262 if (error) { 263 printf("bind failed\n"); 264 goto out; 265 } 266 267 /* 268 * Setup socket address for the server. 269 */ 270 271 /* 272 * Prepend RPC message header. 273 */ 274 mhead = m_gethdr(M_TRYWAIT, MT_DATA); 275 mhead->m_next = *data; 276 call = mtod(mhead, struct rpc_call *); 277 mhead->m_len = sizeof(*call); 278 bzero((caddr_t)call, sizeof(*call)); 279 /* rpc_call part */ 280 xid++; 281 call->rp_xid = txdr_unsigned(xid); 282 /* call->rp_direction = 0; */ 283 call->rp_rpcvers = txdr_unsigned(2); 284 call->rp_prog = txdr_unsigned(prog); 285 call->rp_vers = txdr_unsigned(vers); 286 call->rp_proc = txdr_unsigned(func); 287 /* rpc_auth part (auth_unix as root) */ 288 call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX); 289 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix)); 290 /* rpc_verf part (auth_null) */ 291 call->rpc_verf.authtype = 0; 292 call->rpc_verf.authlen = 0; 293 294 /* 295 * Setup packet header 296 */ 297 len = 0; 298 m = mhead; 299 while (m) { 300 len += m->m_len; 301 m = m->m_next; 302 } 303 mhead->m_pkthdr.len = len; 304 mhead->m_pkthdr.rcvif = NULL; 305 306 /* 307 * Send it, repeatedly, until a reply is received, 308 * but delay each re-send by an increasing amount. 309 * If the delay hits the maximum, start complaining. 310 */ 311 timo = 0; 312 for (;;) { 313 /* Send RPC request (or re-send). */ 314 m = m_copym(mhead, 0, M_COPYALL, M_TRYWAIT); 315 if (m == NULL) { 316 error = ENOBUFS; 317 goto out; 318 } 319 error = sosend(so, (struct sockaddr *)sa, NULL, m, 320 NULL, 0, td); 321 if (error) { 322 printf("krpc_call: sosend: %d\n", error); 323 goto out; 324 } 325 m = NULL; 326 327 /* Determine new timeout. */ 328 if (timo < MAX_RESEND_DELAY) 329 timo++; 330 else { 331 saddr = ntohl(sa->sin_addr.s_addr); 332 printf("RPC timeout for server %d.%d.%d.%d\n", 333 (saddr >> 24) & 255, 334 (saddr >> 16) & 255, 335 (saddr >> 8) & 255, 336 saddr & 255); 337 } 338 339 /* 340 * Wait for up to timo seconds for a reply. 341 * The socket receive timeout was set to 1 second. 342 */ 343 secs = timo; 344 while (secs > 0) { 345 if (from) { 346 FREE(from, M_SONAME); 347 from = NULL; 348 } 349 if (m) { 350 m_freem(m); 351 m = NULL; 352 } 353 bzero(&auio, sizeof(auio)); 354 auio.uio_resid = len = 1<<16; 355 rcvflg = 0; 356 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg); 357 if (error == EWOULDBLOCK) { 358 secs--; 359 continue; 360 } 361 if (error) 362 goto out; 363 len -= auio.uio_resid; 364 365 /* Does the reply contain at least a header? */ 366 if (len < MIN_REPLY_HDR) 367 continue; 368 if (m->m_len < MIN_REPLY_HDR) 369 continue; 370 reply = mtod(m, struct rpc_reply *); 371 372 /* Is it the right reply? */ 373 if (reply->rp_direction != txdr_unsigned(RPC_REPLY)) 374 continue; 375 376 if (reply->rp_xid != txdr_unsigned(xid)) 377 continue; 378 379 /* Was RPC accepted? (authorization OK) */ 380 if (reply->rp_astatus != 0) { 381 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 382 printf("rpc denied, error=%d\n", error); 383 continue; 384 } 385 386 /* Did the call succeed? */ 387 if (reply->rp_status != 0) { 388 error = fxdr_unsigned(u_int32_t, reply->rp_status); 389 if (error == RPC_PROGMISMATCH) { 390 error = EBADRPC; 391 goto out; 392 } 393 printf("rpc denied, status=%d\n", error); 394 continue; 395 } 396 397 goto gotreply; /* break two levels */ 398 399 } /* while secs */ 400 } /* forever send/receive */ 401 402 error = ETIMEDOUT; 403 goto out; 404 405 gotreply: 406 407 /* 408 * Get RPC reply header into first mbuf, 409 * get its length, then strip it off. 410 */ 411 len = sizeof(*reply); 412 if (m->m_len < len) { 413 m = m_pullup(m, len); 414 if (m == NULL) { 415 error = ENOBUFS; 416 goto out; 417 } 418 } 419 reply = mtod(m, struct rpc_reply *); 420 if (reply->rp_auth.authtype != 0) { 421 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 422 len = (len + 3) & ~3; /* XXX? */ 423 } 424 m_adj(m, len); 425 426 /* result */ 427 *data = m; 428 if (from_p) { 429 *from_p = from; 430 from = NULL; 431 } 432 433 out: 434 if (mhead) m_freem(mhead); 435 if (from) free(from, M_SONAME); 436 soclose(so); 437 return error; 438} 439 440/* 441 * eXternal Data Representation routines. 442 * (but with non-standard args...) 443 */ 444 445/* 446 * String representation for RPC. 447 */ 448struct xdr_string { 449 u_int32_t len; /* length without null or padding */ 450 char data[4]; /* data (longer, of course) */ 451 /* data is padded to a long-word boundary */ 452}; 453 454struct mbuf * 455xdr_string_encode(char *str, int len) 456{ 457 struct mbuf *m; 458 struct xdr_string *xs; 459 int dlen; /* padded string length */ 460 int mlen; /* message length */ 461 462 dlen = (len + 3) & ~3; 463 mlen = dlen + 4; 464 465 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 466 return (NULL); 467 468 m = m_get(M_TRYWAIT, MT_DATA); 469 if (mlen > MLEN) { 470 MCLGET(m, M_TRYWAIT); 471 if ((m->m_flags & M_EXT) == 0) { 472 (void) m_free(m); /* There can be only one. */ 473 return (NULL); 474 } 475 } 476 xs = mtod(m, struct xdr_string *); 477 m->m_len = mlen; 478 xs->len = txdr_unsigned(len); 479 bcopy(str, xs->data, len); 480 return (m); 481} 482