krpc_subr.c revision 171744
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 171744 2007-08-06 14:26:03Z 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/proc.h> 53#include <sys/socket.h> 54#include <sys/socketvar.h> 55#include <sys/uio.h> 56 57#include <net/if.h> 58#include <netinet/in.h> 59 60#include <rpc/rpcclnt.h> 61 62#include <nfs/rpcv2.h> 63#include <nfsclient/krpc.h> 64#include <nfs/xdr_subs.h> 65 66/* 67 * Kernel support for Sun RPC 68 * 69 * Used currently for bootstrapping in nfs diskless configurations. 70 */ 71 72/* 73 * Generic RPC headers 74 */ 75 76struct auth_info { 77 u_int32_t authtype; /* auth type */ 78 u_int32_t authlen; /* auth length */ 79}; 80 81struct auth_unix { 82 int32_t ua_time; 83 int32_t ua_hostname; /* null */ 84 int32_t ua_uid; 85 int32_t ua_gid; 86 int32_t ua_gidlist; /* null */ 87}; 88 89struct krpc_call { 90 u_int32_t rp_xid; /* request transaction id */ 91 int32_t rp_direction; /* call direction (0) */ 92 u_int32_t rp_rpcvers; /* rpc version (2) */ 93 u_int32_t rp_prog; /* program */ 94 u_int32_t rp_vers; /* version */ 95 u_int32_t rp_proc; /* procedure */ 96 struct auth_info rpc_auth; 97 struct auth_unix rpc_unix; 98 struct auth_info rpc_verf; 99}; 100 101struct krpc_reply { 102 u_int32_t rp_xid; /* request transaction id */ 103 int32_t rp_direction; /* call direction (1) */ 104 int32_t rp_astatus; /* accept status (0: accepted) */ 105 union { 106 u_int32_t rpu_errno; 107 struct { 108 struct auth_info rok_auth; 109 u_int32_t rok_status; 110 } rpu_rok; 111 } rp_u; 112}; 113#define rp_errno rp_u.rpu_errno 114#define rp_auth rp_u.rpu_rok.rok_auth 115#define rp_status rp_u.rpu_rok.rok_status 116 117#define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 118 119/* 120 * What is the longest we will wait before re-sending a request? 121 * Note this is also the frequency of "RPC timeout" messages. 122 * The re-send loop count sup linearly to this maximum, so the 123 * first complaint will happen after (1+2+3+4+5)=15 seconds. 124 */ 125#define MAX_RESEND_DELAY 5 /* seconds */ 126 127/* 128 * Call portmap to lookup a port number for a particular rpc program 129 * Returns non-zero error on failure. 130 */ 131int 132krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp, 133 struct thread *td) 134{ 135 struct sdata { 136 u_int32_t prog; /* call program */ 137 u_int32_t vers; /* call version */ 138 u_int32_t proto; /* call protocol */ 139 u_int32_t port; /* call port (unused) */ 140 } *sdata; 141 struct rdata { 142 u_int16_t pad; 143 u_int16_t port; 144 } *rdata; 145 struct mbuf *m; 146 int error; 147 148 /* The portmapper port is fixed. */ 149 if (prog == PMAPPROG) { 150 *portp = htons(PMAPPORT); 151 return 0; 152 } 153 154 m = m_get(M_TRYWAIT, MT_DATA); 155 if (m == NULL) 156 return ENOBUFS; 157 sdata = mtod(m, struct sdata *); 158 m->m_len = sizeof(*sdata); 159 160 /* Do the RPC to get it. */ 161 sdata->prog = txdr_unsigned(prog); 162 sdata->vers = txdr_unsigned(vers); 163 sdata->proto = txdr_unsigned(IPPROTO_UDP); 164 sdata->port = 0; 165 166 sin->sin_port = htons(PMAPPORT); 167 error = krpc_call(sin, PMAPPROG, PMAPVERS, 168 PMAPPROC_GETPORT, &m, NULL, td); 169 if (error) 170 return error; 171 172 if (m->m_len < sizeof(*rdata)) { 173 m = m_pullup(m, sizeof(*rdata)); 174 if (m == NULL) 175 return ENOBUFS; 176 } 177 rdata = mtod(m, struct rdata *); 178 *portp = rdata->port; 179 180 m_freem(m); 181 return 0; 182} 183 184/* 185 * Do a remote procedure call (RPC) and wait for its reply. 186 * If from_p is non-null, then we are doing broadcast, and 187 * the address from whence the response came is saved there. 188 */ 189int 190krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 191 struct mbuf **data, struct sockaddr **from_p, struct thread *td) 192{ 193 struct socket *so; 194 struct sockaddr_in *sin, ssin; 195 struct sockaddr *from; 196 struct mbuf *m, *nam, *mhead; 197 struct krpc_call *call; 198 struct krpc_reply *reply; 199 struct sockopt sopt; 200 struct timeval tv; 201 struct uio auio; 202 int error, rcvflg, timo, secs, len; 203 static u_int32_t xid = ~0xFF; 204 u_int16_t tport; 205 u_int32_t saddr; 206 207 /* 208 * Validate address family. 209 * Sorry, this is INET specific... 210 */ 211 if (sa->sin_family != AF_INET) 212 return (EAFNOSUPPORT); 213 214 /* Free at end if not null. */ 215 nam = mhead = NULL; 216 from = NULL; 217 218 /* 219 * Create socket and set its recieve timeout. 220 */ 221 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td->td_ucred, td))) 222 goto out; 223 224 tv.tv_sec = 1; 225 tv.tv_usec = 0; 226 bzero(&sopt, sizeof sopt); 227 sopt.sopt_dir = SOPT_SET; 228 sopt.sopt_level = SOL_SOCKET; 229 sopt.sopt_name = SO_RCVTIMEO; 230 sopt.sopt_val = &tv; 231 sopt.sopt_valsize = sizeof tv; 232 233 if ((error = sosetopt(so, &sopt)) != 0) 234 goto out; 235 236 /* 237 * Enable broadcast if necessary. 238 */ 239 if (from_p) { 240 int on = 1; 241 sopt.sopt_name = SO_BROADCAST; 242 sopt.sopt_val = &on; 243 sopt.sopt_valsize = sizeof on; 244 if ((error = sosetopt(so, &sopt)) != 0) 245 goto out; 246 } 247 248 /* 249 * Bind the local endpoint to a reserved port, 250 * because some NFS servers refuse requests from 251 * non-reserved (non-privileged) ports. 252 */ 253 sin = &ssin; 254 bzero(sin, sizeof *sin); 255 sin->sin_len = sizeof(*sin); 256 sin->sin_family = AF_INET; 257 sin->sin_addr.s_addr = INADDR_ANY; 258 tport = IPPORT_RESERVED; 259 do { 260 tport--; 261 sin->sin_port = htons(tport); 262 error = sobind(so, (struct sockaddr *)sin, td); 263 } while (error == EADDRINUSE && 264 tport > IPPORT_RESERVED / 2); 265 if (error) { 266 printf("bind failed\n"); 267 goto out; 268 } 269 270 /* 271 * Setup socket address for the server. 272 */ 273 274 /* 275 * Prepend RPC message header. 276 */ 277 mhead = m_gethdr(M_TRYWAIT, MT_DATA); 278 mhead->m_next = *data; 279 call = mtod(mhead, struct krpc_call *); 280 mhead->m_len = sizeof(*call); 281 bzero((caddr_t)call, sizeof(*call)); 282 /* rpc_call part */ 283 xid++; 284 call->rp_xid = txdr_unsigned(xid); 285 /* call->rp_direction = 0; */ 286 call->rp_rpcvers = txdr_unsigned(2); 287 call->rp_prog = txdr_unsigned(prog); 288 call->rp_vers = txdr_unsigned(vers); 289 call->rp_proc = txdr_unsigned(func); 290 /* rpc_auth part (auth_unix as root) */ 291 call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX); 292 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix)); 293 /* rpc_verf part (auth_null) */ 294 call->rpc_verf.authtype = 0; 295 call->rpc_verf.authlen = 0; 296 297 /* 298 * Setup packet header 299 */ 300 m_fixhdr(mhead); 301 mhead->m_pkthdr.rcvif = NULL; 302 303 /* 304 * Send it, repeatedly, until a reply is received, 305 * but delay each re-send by an increasing amount. 306 * If the delay hits the maximum, start complaining. 307 */ 308 timo = 0; 309 for (;;) { 310 /* Send RPC request (or re-send). */ 311 m = m_copym(mhead, 0, M_COPYALL, M_TRYWAIT); 312 if (m == NULL) { 313 error = ENOBUFS; 314 goto out; 315 } 316 error = sosend(so, (struct sockaddr *)sa, NULL, m, 317 NULL, 0, td); 318 if (error) { 319 printf("krpc_call: sosend: %d\n", error); 320 goto out; 321 } 322 m = NULL; 323 324 /* Determine new timeout. */ 325 if (timo < MAX_RESEND_DELAY) 326 timo++; 327 else { 328 saddr = ntohl(sa->sin_addr.s_addr); 329 printf("RPC timeout for server %d.%d.%d.%d\n", 330 (saddr >> 24) & 255, 331 (saddr >> 16) & 255, 332 (saddr >> 8) & 255, 333 saddr & 255); 334 } 335 336 /* 337 * Wait for up to timo seconds for a reply. 338 * The socket receive timeout was set to 1 second. 339 */ 340 secs = timo; 341 while (secs > 0) { 342 if (from) { 343 FREE(from, M_SONAME); 344 from = NULL; 345 } 346 if (m) { 347 m_freem(m); 348 m = NULL; 349 } 350 bzero(&auio, sizeof(auio)); 351 auio.uio_resid = len = 1<<16; 352 rcvflg = 0; 353 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg); 354 if (error == EWOULDBLOCK) { 355 secs--; 356 continue; 357 } 358 if (error) 359 goto out; 360 len -= auio.uio_resid; 361 362 /* Does the reply contain at least a header? */ 363 if (len < MIN_REPLY_HDR) 364 continue; 365 if (m->m_len < MIN_REPLY_HDR) 366 continue; 367 reply = mtod(m, struct krpc_reply *); 368 369 /* Is it the right reply? */ 370 if (reply->rp_direction != txdr_unsigned(RPC_REPLY)) 371 continue; 372 373 if (reply->rp_xid != txdr_unsigned(xid)) 374 continue; 375 376 /* Was RPC accepted? (authorization OK) */ 377 if (reply->rp_astatus != 0) { 378 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 379 printf("rpc denied, error=%d\n", error); 380 continue; 381 } 382 383 /* Did the call succeed? */ 384 if (reply->rp_status != 0) { 385 error = fxdr_unsigned(u_int32_t, reply->rp_status); 386 if (error == RPC_PROGMISMATCH) { 387 error = EBADRPC; 388 goto out; 389 } 390 printf("rpc denied, status=%d\n", error); 391 continue; 392 } 393 394 goto gotreply; /* break two levels */ 395 396 } /* while secs */ 397 } /* forever send/receive */ 398 399 error = ETIMEDOUT; 400 goto out; 401 402 gotreply: 403 404 /* 405 * Get RPC reply header into first mbuf, 406 * get its length, then strip it off. 407 */ 408 len = sizeof(*reply); 409 if (m->m_len < len) { 410 m = m_pullup(m, len); 411 if (m == NULL) { 412 error = ENOBUFS; 413 goto out; 414 } 415 } 416 reply = mtod(m, struct krpc_reply *); 417 if (reply->rp_auth.authtype != 0) { 418 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 419 len = (len + 3) & ~3; /* XXX? */ 420 } 421 m_adj(m, len); 422 423 /* result */ 424 *data = m; 425 if (from_p) { 426 *from_p = from; 427 from = NULL; 428 } 429 430 out: 431 if (mhead) m_freem(mhead); 432 if (from) free(from, M_SONAME); 433 soclose(so); 434 return error; 435} 436 437/* 438 * eXternal Data Representation routines. 439 * (but with non-standard args...) 440 */ 441 442/* 443 * String representation for RPC. 444 */ 445struct xdr_string { 446 u_int32_t len; /* length without null or padding */ 447 char data[4]; /* data (longer, of course) */ 448 /* data is padded to a long-word boundary */ 449}; 450 451struct mbuf * 452xdr_string_encode(char *str, int len) 453{ 454 struct mbuf *m; 455 struct xdr_string *xs; 456 int dlen; /* padded string length */ 457 int mlen; /* message length */ 458 459 dlen = (len + 3) & ~3; 460 mlen = dlen + 4; 461 462 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 463 return (NULL); 464 465 m = m_get(M_TRYWAIT, MT_DATA); 466 if (mlen > MLEN) { 467 MCLGET(m, M_TRYWAIT); 468 if ((m->m_flags & M_EXT) == 0) { 469 (void) m_free(m); /* There can be only one. */ 470 return (NULL); 471 } 472 } 473 xs = mtod(m, struct xdr_string *); 474 m->m_len = mlen; 475 xs->len = txdr_unsigned(len); 476 bcopy(str, xs->data, len); 477 return (m); 478} 479