1 /* $NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd Exp $ */ 2 /* $FreeBSD: src/sys/nfs/krpc_subr.c,v 1.13.2.1 2000/11/20 21:17:14 tegge Exp $ */ 3 /* $DragonFly: src/sys/vfs/nfs/krpc_subr.c,v 1.2 2003/06/17 04:28:54 dillon Exp $ */ 4 5 /* 6 * Copyright (c) 1995 Gordon Ross, Adam Glass 7 * Copyright (c) 1992 Regents of the University of California. 8 * All rights reserved. 9 * 10 * This software was developed by the Computer Systems Engineering group 11 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 12 * contributed to Berkeley. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. All advertising materials mentioning features or use of this software 23 * must display the following acknowledgement: 24 * This product includes software developed by the University of 25 * California, Lawrence Berkeley Laboratory and its contributors. 26 * 4. Neither the name of the University nor the names of its contributors 27 * may be used to endorse or promote products derived from this software 28 * without specific prior written permission. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 33 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 40 * SUCH DAMAGE. 41 * 42 * partially based on: 43 * libnetboot/rpc.c 44 * @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL) 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/malloc.h> 50 #include <sys/mbuf.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/uio.h> 54 55 #include <net/if.h> 56 #include <netinet/in.h> 57 58 #include <nfs/rpcv2.h> 59 #include <nfs/krpc.h> 60 #include <nfs/xdr_subs.h> 61 62 /* 63 * Kernel support for Sun RPC 64 * 65 * Used currently for bootstrapping in nfs diskless configurations. 66 */ 67 68 /* 69 * Generic RPC headers 70 */ 71 72 struct auth_info { 73 u_int32_t authtype; /* auth type */ 74 u_int32_t authlen; /* auth length */ 75 }; 76 77 struct auth_unix { 78 int32_t ua_time; 79 int32_t ua_hostname; /* null */ 80 int32_t ua_uid; 81 int32_t ua_gid; 82 int32_t ua_gidlist; /* null */ 83 }; 84 85 struct rpc_call { 86 u_int32_t rp_xid; /* request transaction id */ 87 int32_t rp_direction; /* call direction (0) */ 88 u_int32_t rp_rpcvers; /* rpc version (2) */ 89 u_int32_t rp_prog; /* program */ 90 u_int32_t rp_vers; /* version */ 91 u_int32_t rp_proc; /* procedure */ 92 struct auth_info rpc_auth; 93 struct auth_unix rpc_unix; 94 struct auth_info rpc_verf; 95 }; 96 97 struct rpc_reply { 98 u_int32_t rp_xid; /* request transaction id */ 99 int32_t rp_direction; /* call direction (1) */ 100 int32_t rp_astatus; /* accept status (0: accepted) */ 101 union { 102 u_int32_t rpu_errno; 103 struct { 104 struct auth_info rok_auth; 105 u_int32_t rok_status; 106 } rpu_rok; 107 } rp_u; 108 }; 109 #define rp_errno rp_u.rpu_errno 110 #define rp_auth rp_u.rpu_rok.rok_auth 111 #define rp_status rp_u.rpu_rok.rok_status 112 113 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 114 115 /* 116 * What is the longest we will wait before re-sending a request? 117 * Note this is also the frequency of "RPC timeout" messages. 118 * The re-send loop count sup linearly to this maximum, so the 119 * first complaint will happen after (1+2+3+4+5)=15 seconds. 120 */ 121 #define MAX_RESEND_DELAY 5 /* seconds */ 122 123 /* 124 * Call portmap to lookup a port number for a particular rpc program 125 * Returns non-zero error on failure. 126 */ 127 int 128 krpc_portmap(sin, prog, vers, portp, procp) 129 struct sockaddr_in *sin; /* server address */ 130 u_int prog, vers; /* host order */ 131 u_int16_t *portp; /* network order */ 132 struct proc *procp; 133 { 134 struct sdata { 135 u_int32_t prog; /* call program */ 136 u_int32_t vers; /* call version */ 137 u_int32_t proto; /* call protocol */ 138 u_int32_t port; /* call port (unused) */ 139 } *sdata; 140 struct rdata { 141 u_int16_t pad; 142 u_int16_t port; 143 } *rdata; 144 struct mbuf *m; 145 int error; 146 147 /* The portmapper port is fixed. */ 148 if (prog == PMAPPROG) { 149 *portp = htons(PMAPPORT); 150 return 0; 151 } 152 153 m = m_get(M_WAIT, MT_DATA); 154 if (m == NULL) 155 return ENOBUFS; 156 sdata = mtod(m, struct sdata *); 157 m->m_len = sizeof(*sdata); 158 159 /* Do the RPC to get it. */ 160 sdata->prog = txdr_unsigned(prog); 161 sdata->vers = txdr_unsigned(vers); 162 sdata->proto = txdr_unsigned(IPPROTO_UDP); 163 sdata->port = 0; 164 165 sin->sin_port = htons(PMAPPORT); 166 error = krpc_call(sin, PMAPPROG, PMAPVERS, 167 PMAPPROC_GETPORT, &m, NULL, procp); 168 if (error) 169 return error; 170 171 if (m->m_len < sizeof(*rdata)) { 172 m = m_pullup(m, sizeof(*rdata)); 173 if (m == NULL) 174 return ENOBUFS; 175 } 176 rdata = mtod(m, struct rdata *); 177 *portp = rdata->port; 178 179 m_freem(m); 180 return 0; 181 } 182 183 /* 184 * Do a remote procedure call (RPC) and wait for its reply. 185 * If from_p is non-null, then we are doing broadcast, and 186 * the address from whence the response came is saved there. 187 */ 188 int 189 krpc_call(sa, prog, vers, func, data, from_p, procp) 190 struct sockaddr_in *sa; 191 u_int prog, vers, func; 192 struct mbuf **data; /* input/output */ 193 struct sockaddr **from_p; /* output */ 194 struct proc *procp; 195 { 196 struct socket *so; 197 struct sockaddr_in *sin, ssin; 198 struct sockaddr *from; 199 struct mbuf *m, *nam, *mhead; 200 struct rpc_call *call; 201 struct rpc_reply *reply; 202 struct sockopt sopt; 203 struct timeval tv; 204 struct uio auio; 205 int error, rcvflg, timo, secs, len; 206 static u_int32_t xid = ~0xFF; 207 u_int16_t tport; 208 u_int32_t saddr; 209 210 /* 211 * Validate address family. 212 * Sorry, this is INET specific... 213 */ 214 if (sa->sin_family != AF_INET) 215 return (EAFNOSUPPORT); 216 217 /* Free at end if not null. */ 218 nam = mhead = NULL; 219 from = NULL; 220 221 /* 222 * Create socket and set its recieve timeout. 223 */ 224 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, procp))) 225 goto out; 226 227 tv.tv_sec = 1; 228 tv.tv_usec = 0; 229 bzero(&sopt, sizeof sopt); 230 sopt.sopt_level = SOL_SOCKET; 231 sopt.sopt_name = SO_RCVTIMEO; 232 sopt.sopt_val = &tv; 233 sopt.sopt_valsize = sizeof tv; 234 235 if ((error = sosetopt(so, &sopt)) != 0) 236 goto out; 237 238 /* 239 * Enable broadcast if necessary. 240 */ 241 if (from_p) { 242 int on = 1; 243 sopt.sopt_name = SO_BROADCAST; 244 sopt.sopt_val = &on; 245 sopt.sopt_valsize = sizeof on; 246 if ((error = sosetopt(so, &sopt)) != 0) 247 goto out; 248 } 249 250 /* 251 * Bind the local endpoint to a reserved port, 252 * because some NFS servers refuse requests from 253 * non-reserved (non-privileged) ports. 254 */ 255 sin = &ssin; 256 bzero(sin, sizeof *sin); 257 sin->sin_len = sizeof(*sin); 258 sin->sin_family = AF_INET; 259 sin->sin_addr.s_addr = INADDR_ANY; 260 tport = IPPORT_RESERVED; 261 do { 262 tport--; 263 sin->sin_port = htons(tport); 264 error = sobind(so, (struct sockaddr *)sin, procp); 265 } while (error == EADDRINUSE && 266 tport > IPPORT_RESERVED / 2); 267 if (error) { 268 printf("bind failed\n"); 269 goto out; 270 } 271 272 /* 273 * Setup socket address for the server. 274 */ 275 276 /* 277 * Prepend RPC message header. 278 */ 279 mhead = m_gethdr(M_WAIT, MT_DATA); 280 mhead->m_next = *data; 281 call = mtod(mhead, struct rpc_call *); 282 mhead->m_len = sizeof(*call); 283 bzero((caddr_t)call, sizeof(*call)); 284 /* rpc_call part */ 285 xid++; 286 call->rp_xid = txdr_unsigned(xid); 287 /* call->rp_direction = 0; */ 288 call->rp_rpcvers = txdr_unsigned(2); 289 call->rp_prog = txdr_unsigned(prog); 290 call->rp_vers = txdr_unsigned(vers); 291 call->rp_proc = txdr_unsigned(func); 292 /* rpc_auth part (auth_unix as root) */ 293 call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX); 294 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix)); 295 /* rpc_verf part (auth_null) */ 296 call->rpc_verf.authtype = 0; 297 call->rpc_verf.authlen = 0; 298 299 /* 300 * Setup packet header 301 */ 302 len = 0; 303 m = mhead; 304 while (m) { 305 len += m->m_len; 306 m = m->m_next; 307 } 308 mhead->m_pkthdr.len = len; 309 mhead->m_pkthdr.rcvif = NULL; 310 311 /* 312 * Send it, repeatedly, until a reply is received, 313 * but delay each re-send by an increasing amount. 314 * If the delay hits the maximum, start complaining. 315 */ 316 timo = 0; 317 for (;;) { 318 /* Send RPC request (or re-send). */ 319 m = m_copym(mhead, 0, M_COPYALL, M_WAIT); 320 if (m == NULL) { 321 error = ENOBUFS; 322 goto out; 323 } 324 error = sosend(so, (struct sockaddr *)sa, NULL, m, 325 NULL, 0, procp); 326 if (error) { 327 printf("krpc_call: sosend: %d\n", error); 328 goto out; 329 } 330 m = NULL; 331 332 /* Determine new timeout. */ 333 if (timo < MAX_RESEND_DELAY) 334 timo++; 335 else { 336 saddr = ntohl(sa->sin_addr.s_addr); 337 printf("RPC timeout for server %d.%d.%d.%d\n", 338 (saddr >> 24) & 255, 339 (saddr >> 16) & 255, 340 (saddr >> 8) & 255, 341 saddr & 255); 342 } 343 344 /* 345 * Wait for up to timo seconds for a reply. 346 * The socket receive timeout was set to 1 second. 347 */ 348 secs = timo; 349 while (secs > 0) { 350 if (from) { 351 FREE(from, M_SONAME); 352 from = NULL; 353 } 354 if (m) { 355 m_freem(m); 356 m = NULL; 357 } 358 bzero(&auio,sizeof(auio)); 359 auio.uio_resid = len = 1<<16; 360 rcvflg = 0; 361 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg); 362 if (error == EWOULDBLOCK) { 363 secs--; 364 continue; 365 } 366 if (error) 367 goto out; 368 len -= auio.uio_resid; 369 370 /* Does the reply contain at least a header? */ 371 if (len < MIN_REPLY_HDR) 372 continue; 373 if (m->m_len < MIN_REPLY_HDR) 374 continue; 375 reply = mtod(m, struct rpc_reply *); 376 377 /* Is it the right reply? */ 378 if (reply->rp_direction != txdr_unsigned(RPC_REPLY)) 379 continue; 380 381 if (reply->rp_xid != txdr_unsigned(xid)) 382 continue; 383 384 /* Was RPC accepted? (authorization OK) */ 385 if (reply->rp_astatus != 0) { 386 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 387 printf("rpc denied, error=%d\n", error); 388 continue; 389 } 390 391 /* Did the call succeed? */ 392 if (reply->rp_status != 0) { 393 error = fxdr_unsigned(u_int32_t, reply->rp_status); 394 if (error == RPC_PROGMISMATCH) { 395 error = EBADRPC; 396 goto out; 397 } 398 printf("rpc denied, status=%d\n", error); 399 continue; 400 } 401 402 goto gotreply; /* break two levels */ 403 404 } /* while secs */ 405 } /* forever send/receive */ 406 407 error = ETIMEDOUT; 408 goto out; 409 410 gotreply: 411 412 /* 413 * Get RPC reply header into first mbuf, 414 * get its length, then strip it off. 415 */ 416 len = sizeof(*reply); 417 if (m->m_len < len) { 418 m = m_pullup(m, len); 419 if (m == NULL) { 420 error = ENOBUFS; 421 goto out; 422 } 423 } 424 reply = mtod(m, struct rpc_reply *); 425 if (reply->rp_auth.authtype != 0) { 426 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 427 len = (len + 3) & ~3; /* XXX? */ 428 } 429 m_adj(m, len); 430 431 /* result */ 432 *data = m; 433 if (from_p) { 434 *from_p = from; 435 from = NULL; 436 } 437 438 out: 439 if (mhead) m_freem(mhead); 440 if (from) free(from, M_SONAME); 441 soclose(so); 442 return error; 443 } 444 445 /* 446 * eXternal Data Representation routines. 447 * (but with non-standard args...) 448 */ 449 450 /* 451 * String representation for RPC. 452 */ 453 struct xdr_string { 454 u_int32_t len; /* length without null or padding */ 455 char data[4]; /* data (longer, of course) */ 456 /* data is padded to a long-word boundary */ 457 }; 458 459 struct mbuf * 460 xdr_string_encode(str, len) 461 char *str; 462 int len; 463 { 464 struct mbuf *m; 465 struct xdr_string *xs; 466 int dlen; /* padded string length */ 467 int mlen; /* message length */ 468 469 dlen = (len + 3) & ~3; 470 mlen = dlen + 4; 471 472 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 473 return (NULL); 474 475 m = m_get(M_WAIT, MT_DATA); 476 if (mlen > MLEN) { 477 MCLGET(m, M_WAIT); 478 if ((m->m_flags & M_EXT) == 0) { 479 (void) m_free(m); /* There can be only one. */ 480 return (NULL); 481 } 482 } 483 xs = mtod(m, struct xdr_string *); 484 m->m_len = mlen; 485 xs->len = txdr_unsigned(len); 486 bcopy(str, xs->data, len); 487 return (m); 488 } 489