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