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 1.12 2007/04/22 01:13:17 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 #include <sys/fcntl.h> 55 56 #include <net/if.h> 57 #include <netinet/in.h> 58 59 #include "rpcv2.h" 60 #include "krpc.h" 61 #include "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 73 struct auth_info { 74 u_int32_t authtype; /* auth type */ 75 u_int32_t authlen; /* auth length */ 76 }; 77 78 struct 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 86 struct 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 98 struct 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 */ 128 int 129 krpc_portmap(struct sockaddr_in *sin, /* server address */ 130 u_int prog, u_int vers, /* host order */ 131 u_int16_t *portp, /* network order */ 132 struct thread *td) 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(MB_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, td); 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(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 190 struct mbuf **data, /* input/output */ 191 struct sockaddr **from_p, /* output */ 192 struct thread *td) 193 { 194 struct socket *so; 195 struct sockaddr_in *sin, ssin; 196 struct sockaddr *from; 197 struct mbuf *m, *nam, *mhead; 198 struct rpc_call *call; 199 struct rpc_reply *reply; 200 struct sockopt sopt; 201 struct timeval tv; 202 struct sockbuf sio; 203 int error, rcvflg, timo, secs, len; 204 static u_int32_t static_xid = ~0xFF; 205 u_int32_t xid; 206 u_int16_t tport; 207 u_int32_t saddr; 208 209 /* 210 * Validate address family. 211 * Sorry, this is INET specific... 212 */ 213 if (sa->sin_family != AF_INET) 214 return (EAFNOSUPPORT); 215 216 /* Free at end if not null. */ 217 nam = mhead = NULL; 218 from = NULL; 219 220 /* 221 * Create socket and set its recieve timeout. 222 */ 223 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td))) 224 goto out; 225 226 tv.tv_sec = 1; 227 tv.tv_usec = 0; 228 bzero(&sopt, sizeof sopt); 229 sopt.sopt_level = SOL_SOCKET; 230 sopt.sopt_name = SO_RCVTIMEO; 231 sopt.sopt_val = &tv; 232 sopt.sopt_valsize = sizeof tv; 233 234 if ((error = sosetopt(so, &sopt)) != 0) 235 goto out; 236 237 /* 238 * Enable broadcast if necessary. 239 */ 240 if (from_p) { 241 int on = 1; 242 sopt.sopt_name = SO_BROADCAST; 243 sopt.sopt_val = &on; 244 sopt.sopt_valsize = sizeof on; 245 if ((error = sosetopt(so, &sopt)) != 0) 246 goto out; 247 } 248 249 /* 250 * Bind the local endpoint to a reserved port, 251 * because some NFS servers refuse requests from 252 * non-reserved (non-privileged) ports. 253 */ 254 sin = &ssin; 255 bzero(sin, sizeof *sin); 256 sin->sin_len = sizeof(*sin); 257 sin->sin_family = AF_INET; 258 sin->sin_addr.s_addr = INADDR_ANY; 259 tport = IPPORT_RESERVED; 260 do { 261 tport--; 262 sin->sin_port = htons(tport); 263 error = sobind(so, (struct sockaddr *)sin, td); 264 } while (error == EADDRINUSE && 265 tport > IPPORT_RESERVED / 2); 266 if (error) { 267 kprintf("bind failed\n"); 268 goto out; 269 } 270 271 /* 272 * Setup socket address for the server. 273 */ 274 275 /* 276 * Prepend RPC message header. 277 */ 278 mhead = m_gethdr(MB_WAIT, MT_DATA); 279 mhead->m_next = *data; 280 call = mtod(mhead, struct rpc_call *); 281 mhead->m_len = sizeof(*call); 282 bzero((caddr_t)call, sizeof(*call)); 283 /* rpc_call part */ 284 do { 285 xid = atomic_fetchadd_int(&static_xid, 1); 286 } while (xid == 0); 287 call->rp_xid = txdr_unsigned(xid); 288 /* call->rp_direction = 0; */ 289 call->rp_rpcvers = txdr_unsigned(2); 290 call->rp_prog = txdr_unsigned(prog); 291 call->rp_vers = txdr_unsigned(vers); 292 call->rp_proc = txdr_unsigned(func); 293 /* rpc_auth part (auth_unix as root) */ 294 call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX); 295 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix)); 296 /* rpc_verf part (auth_null) */ 297 call->rpc_verf.authtype = 0; 298 call->rpc_verf.authlen = 0; 299 300 /* 301 * Setup packet header 302 */ 303 len = 0; 304 m = mhead; 305 while (m) { 306 len += m->m_len; 307 m = m->m_next; 308 } 309 mhead->m_pkthdr.len = len; 310 mhead->m_pkthdr.rcvif = NULL; 311 312 /* 313 * Send it, repeatedly, until a reply is received, 314 * but delay each re-send by an increasing amount. 315 * If the delay hits the maximum, start complaining. 316 */ 317 timo = 0; 318 for (;;) { 319 /* Send RPC request (or re-send). */ 320 m = m_copym(mhead, 0, M_COPYALL, MB_WAIT); 321 if (m == NULL) { 322 error = ENOBUFS; 323 goto out; 324 } 325 error = sosend(so, (struct sockaddr *)sa, NULL, m, 326 NULL, 0, td); 327 if (error) { 328 kprintf("krpc_call: sosend: %d\n", error); 329 goto out; 330 } 331 m = NULL; 332 333 /* Determine new timeout. */ 334 if (timo < MAX_RESEND_DELAY) 335 timo++; 336 else { 337 saddr = ntohl(sa->sin_addr.s_addr); 338 kprintf("RPC timeout for server %d.%d.%d.%d\n", 339 (saddr >> 24) & 255, 340 (saddr >> 16) & 255, 341 (saddr >> 8) & 255, 342 saddr & 255); 343 } 344 345 /* 346 * Wait for up to timo seconds for a reply. 347 * The socket receive timeout was set to 1 second. 348 */ 349 secs = timo; 350 while (secs > 0) { 351 if (from) { 352 FREE(from, M_SONAME); 353 from = NULL; 354 } 355 if (m) { 356 m_freem(m); 357 m = NULL; 358 } 359 len = 1 << 16; 360 sbinit(&sio, len); 361 rcvflg = 0; 362 error = soreceive(so, &from, NULL, &sio, NULL, &rcvflg); 363 if (error == EWOULDBLOCK) { 364 secs--; 365 continue; 366 } 367 if (error) 368 goto out; 369 len -= sio.sb_cc; 370 m = sio.sb_mb; 371 372 /* Does the reply contain at least a header? */ 373 if (len < MIN_REPLY_HDR) 374 continue; 375 if (m->m_len < MIN_REPLY_HDR) 376 continue; 377 reply = mtod(m, struct rpc_reply *); 378 379 /* Is it the right reply? */ 380 if (reply->rp_direction != txdr_unsigned(RPC_REPLY)) 381 continue; 382 383 if (reply->rp_xid != txdr_unsigned(xid)) 384 continue; 385 386 /* Was RPC accepted? (authorization OK) */ 387 if (reply->rp_astatus != 0) { 388 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 389 kprintf("rpc denied, error=%d\n", error); 390 continue; 391 } 392 393 /* Did the call succeed? */ 394 if (reply->rp_status != 0) { 395 error = fxdr_unsigned(u_int32_t, reply->rp_status); 396 if (error == RPC_PROGMISMATCH) { 397 error = EBADRPC; 398 goto out; 399 } 400 kprintf("rpc denied, status=%d\n", error); 401 continue; 402 } 403 404 goto gotreply; /* break two levels */ 405 406 } /* while secs */ 407 } /* forever send/receive */ 408 409 error = ETIMEDOUT; 410 goto out; 411 412 gotreply: 413 414 /* 415 * Get RPC reply header into first mbuf, 416 * get its length, then strip it off. 417 */ 418 len = sizeof(*reply); 419 if (m->m_len < len) { 420 m = m_pullup(m, len); 421 if (m == NULL) { 422 error = ENOBUFS; 423 goto out; 424 } 425 } 426 reply = mtod(m, struct rpc_reply *); 427 if (reply->rp_auth.authtype != 0) { 428 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 429 len = (len + 3) & ~3; /* XXX? */ 430 } 431 m_adj(m, len); 432 433 /* result */ 434 *data = m; 435 if (from_p) { 436 *from_p = from; 437 from = NULL; 438 } 439 440 out: 441 if (mhead) m_freem(mhead); 442 if (from) kfree(from, M_SONAME); 443 soclose(so, FNONBLOCK); 444 return error; 445 } 446 447 /* 448 * eXternal Data Representation routines. 449 * (but with non-standard args...) 450 */ 451 452 /* 453 * String representation for RPC. 454 */ 455 struct xdr_string { 456 u_int32_t len; /* length without null or padding */ 457 char data[4]; /* data (longer, of course) */ 458 /* data is padded to a long-word boundary */ 459 }; 460 461 struct mbuf * 462 xdr_string_encode(char *str, 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_getl(mlen, MB_WAIT, MT_DATA, 0, NULL); 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