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 #include <sys/fcntl.h> 54 55 #include <net/if.h> 56 #include <netinet/in.h> 57 58 #include "rpcv2.h" 59 #include "krpc.h" 60 #include "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(struct sockaddr_in *sin, /* server address */ 129 u_int prog, u_int vers, /* host order */ 130 u_int16_t *portp, /* network order */ 131 struct thread *td) 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_WAITOK, MT_DATA); 153 sdata = mtod(m, struct sdata *); 154 m->m_len = sizeof(*sdata); 155 156 /* Do the RPC to get it. */ 157 sdata->prog = txdr_unsigned(prog); 158 sdata->vers = txdr_unsigned(vers); 159 sdata->proto = txdr_unsigned(IPPROTO_UDP); 160 sdata->port = 0; 161 162 sin->sin_port = htons(PMAPPORT); 163 error = krpc_call(sin, PMAPPROG, PMAPVERS, 164 PMAPPROC_GETPORT, &m, NULL, td); 165 if (error) 166 return error; 167 168 if (m->m_len < sizeof(*rdata)) { 169 m = m_pullup(m, sizeof(*rdata)); 170 if (m == NULL) 171 return ENOBUFS; 172 } 173 rdata = mtod(m, struct rdata *); 174 *portp = rdata->port; 175 176 m_freem(m); 177 return 0; 178 } 179 180 /* 181 * Do a remote procedure call (RPC) and wait for its reply. 182 * If from_p is non-null, then we are doing broadcast, and 183 * the address from whence the response came is saved there. 184 */ 185 int 186 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 187 struct mbuf **data, /* input/output */ 188 struct sockaddr **from_p, /* output */ 189 struct thread *td) 190 { 191 struct socket *so; 192 struct sockaddr_in *sin, ssin; 193 struct sockaddr *from; 194 struct mbuf *m, *mhead; 195 struct rpc_call *call; 196 struct rpc_reply *reply; 197 struct sockopt sopt; 198 struct timeval tv; 199 struct sockbuf sio; 200 int error, rcvflg, timo, secs, len; 201 static u_int32_t static_xid = ~0xFF; 202 u_int32_t xid; 203 u_int16_t tport; 204 u_int32_t saddr; 205 206 /* 207 * Validate address family. 208 * Sorry, this is INET specific... 209 */ 210 if (sa->sin_family != AF_INET) 211 return (EAFNOSUPPORT); 212 213 /* Free at end if not null. */ 214 mhead = NULL; 215 from = NULL; 216 217 /* 218 * Create socket and set its recieve timeout. 219 */ 220 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td))) 221 goto out; 222 223 tv.tv_sec = 1; 224 tv.tv_usec = 0; 225 bzero(&sopt, sizeof sopt); 226 sopt.sopt_level = SOL_SOCKET; 227 sopt.sopt_name = SO_RCVTIMEO; 228 sopt.sopt_val = &tv; 229 sopt.sopt_valsize = sizeof tv; 230 231 if ((error = sosetopt(so, &sopt)) != 0) 232 goto out; 233 234 /* 235 * Enable broadcast if necessary. 236 */ 237 if (from_p) { 238 int on = 1; 239 sopt.sopt_name = SO_BROADCAST; 240 sopt.sopt_val = &on; 241 sopt.sopt_valsize = sizeof on; 242 if ((error = sosetopt(so, &sopt)) != 0) 243 goto out; 244 } 245 246 /* 247 * Bind the local endpoint to a reserved port, 248 * because some NFS servers refuse requests from 249 * non-reserved (non-privileged) ports. 250 */ 251 sin = &ssin; 252 bzero(sin, sizeof *sin); 253 sin->sin_len = sizeof(*sin); 254 sin->sin_family = AF_INET; 255 sin->sin_addr.s_addr = INADDR_ANY; 256 tport = IPPORT_RESERVED; 257 do { 258 tport--; 259 sin->sin_port = htons(tport); 260 error = sobind(so, (struct sockaddr *)sin, td); 261 } while (error == EADDRINUSE && 262 tport > IPPORT_RESERVED / 2); 263 if (error) { 264 kprintf("bind failed\n"); 265 goto out; 266 } 267 268 /* 269 * Setup socket address for the server. 270 */ 271 272 /* 273 * Prepend RPC message header. 274 */ 275 mhead = m_gethdr(M_WAITOK, MT_DATA); 276 mhead->m_next = *data; 277 call = mtod(mhead, struct rpc_call *); 278 mhead->m_len = sizeof(*call); 279 bzero((caddr_t)call, sizeof(*call)); 280 /* rpc_call part */ 281 do { 282 xid = atomic_fetchadd_int(&static_xid, 1); 283 } while (xid == 0); 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 len = 0; 301 m = mhead; 302 while (m) { 303 len += m->m_len; 304 m = m->m_next; 305 } 306 mhead->m_pkthdr.len = len; 307 mhead->m_pkthdr.rcvif = NULL; 308 309 /* 310 * Send it, repeatedly, until a reply is received, 311 * but delay each re-send by an increasing amount. 312 * If the delay hits the maximum, start complaining. 313 */ 314 timo = 0; 315 for (;;) { 316 /* Send RPC request (or re-send). */ 317 m = m_copym(mhead, 0, M_COPYALL, M_WAITOK); 318 if (m == NULL) { 319 error = ENOBUFS; 320 goto out; 321 } 322 error = sosend(so, (struct sockaddr *)sa, NULL, m, 323 NULL, 0, td); 324 if (error) { 325 kprintf("krpc_call: sosend: %d\n", error); 326 goto out; 327 } 328 m = NULL; 329 330 /* Determine new timeout. */ 331 if (timo < MAX_RESEND_DELAY) 332 timo++; 333 else { 334 saddr = ntohl(sa->sin_addr.s_addr); 335 kprintf("RPC timeout for server %d.%d.%d.%d\n", 336 (saddr >> 24) & 255, 337 (saddr >> 16) & 255, 338 (saddr >> 8) & 255, 339 saddr & 255); 340 } 341 342 /* 343 * Wait for up to timo seconds for a reply. 344 * The socket receive timeout was set to 1 second. 345 */ 346 secs = timo; 347 while (secs > 0) { 348 if (from) { 349 kfree(from, M_SONAME); 350 from = NULL; 351 } 352 if (m) { 353 m_freem(m); 354 m = NULL; 355 } 356 len = 1 << 16; 357 sbinit(&sio, len); 358 rcvflg = 0; 359 error = soreceive(so, &from, NULL, &sio, NULL, &rcvflg); 360 if (error == EWOULDBLOCK) { 361 secs--; 362 continue; 363 } 364 if (error) 365 goto out; 366 len -= sio.sb_cc; 367 m = sio.sb_mb; 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 kprintf("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 kprintf("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) kfree(from, M_SONAME); 440 soclose(so, FNONBLOCK); 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(char *str, int len) 460 { 461 struct mbuf *m; 462 struct xdr_string *xs; 463 int dlen; /* padded string length */ 464 int mlen; /* message length */ 465 466 dlen = (len + 3) & ~3; 467 mlen = dlen + 4; 468 469 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 470 return (NULL); 471 472 m = m_getl(mlen, M_WAITOK, MT_DATA, 0, NULL); 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