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(MB_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, td); 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(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 189 struct mbuf **data, /* input/output */ 190 struct sockaddr **from_p, /* output */ 191 struct thread *td) 192 { 193 struct socket *so; 194 struct sockaddr_in *sin, ssin; 195 struct sockaddr *from; 196 struct mbuf *m, *mhead; 197 struct rpc_call *call; 198 struct rpc_reply *reply; 199 struct sockopt sopt; 200 struct timeval tv; 201 struct sockbuf sio; 202 int error, rcvflg, timo, secs, len; 203 static u_int32_t static_xid = ~0xFF; 204 u_int32_t xid; 205 u_int16_t tport; 206 u_int32_t saddr; 207 208 /* 209 * Validate address family. 210 * Sorry, this is INET specific... 211 */ 212 if (sa->sin_family != AF_INET) 213 return (EAFNOSUPPORT); 214 215 /* Free at end if not null. */ 216 mhead = NULL; 217 from = NULL; 218 219 /* 220 * Create socket and set its recieve timeout. 221 */ 222 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td))) 223 goto out; 224 225 tv.tv_sec = 1; 226 tv.tv_usec = 0; 227 bzero(&sopt, sizeof sopt); 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 kprintf("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(MB_WAIT, MT_DATA); 278 mhead->m_next = *data; 279 call = mtod(mhead, struct rpc_call *); 280 mhead->m_len = sizeof(*call); 281 bzero((caddr_t)call, sizeof(*call)); 282 /* rpc_call part */ 283 do { 284 xid = atomic_fetchadd_int(&static_xid, 1); 285 } while (xid == 0); 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, MB_WAIT); 320 if (m == NULL) { 321 error = ENOBUFS; 322 goto out; 323 } 324 error = sosend(so, (struct sockaddr *)sa, NULL, m, 325 NULL, 0, td); 326 if (error) { 327 kprintf("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 kprintf("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 kfree(from, M_SONAME); 352 from = NULL; 353 } 354 if (m) { 355 m_freem(m); 356 m = NULL; 357 } 358 len = 1 << 16; 359 sbinit(&sio, len); 360 rcvflg = 0; 361 error = soreceive(so, &from, NULL, &sio, NULL, &rcvflg); 362 if (error == EWOULDBLOCK) { 363 secs--; 364 continue; 365 } 366 if (error) 367 goto out; 368 len -= sio.sb_cc; 369 m = sio.sb_mb; 370 371 /* Does the reply contain at least a header? */ 372 if (len < MIN_REPLY_HDR) 373 continue; 374 if (m->m_len < MIN_REPLY_HDR) 375 continue; 376 reply = mtod(m, struct rpc_reply *); 377 378 /* Is it the right reply? */ 379 if (reply->rp_direction != txdr_unsigned(RPC_REPLY)) 380 continue; 381 382 if (reply->rp_xid != txdr_unsigned(xid)) 383 continue; 384 385 /* Was RPC accepted? (authorization OK) */ 386 if (reply->rp_astatus != 0) { 387 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 388 kprintf("rpc denied, error=%d\n", error); 389 continue; 390 } 391 392 /* Did the call succeed? */ 393 if (reply->rp_status != 0) { 394 error = fxdr_unsigned(u_int32_t, reply->rp_status); 395 if (error == RPC_PROGMISMATCH) { 396 error = EBADRPC; 397 goto out; 398 } 399 kprintf("rpc denied, status=%d\n", error); 400 continue; 401 } 402 403 goto gotreply; /* break two levels */ 404 405 } /* while secs */ 406 } /* forever send/receive */ 407 408 error = ETIMEDOUT; 409 goto out; 410 411 gotreply: 412 413 /* 414 * Get RPC reply header into first mbuf, 415 * get its length, then strip it off. 416 */ 417 len = sizeof(*reply); 418 if (m->m_len < len) { 419 m = m_pullup(m, len); 420 if (m == NULL) { 421 error = ENOBUFS; 422 goto out; 423 } 424 } 425 reply = mtod(m, struct rpc_reply *); 426 if (reply->rp_auth.authtype != 0) { 427 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 428 len = (len + 3) & ~3; /* XXX? */ 429 } 430 m_adj(m, len); 431 432 /* result */ 433 *data = m; 434 if (from_p) { 435 *from_p = from; 436 from = NULL; 437 } 438 439 out: 440 if (mhead) m_freem(mhead); 441 if (from) kfree(from, M_SONAME); 442 soclose(so, FNONBLOCK); 443 return error; 444 } 445 446 /* 447 * eXternal Data Representation routines. 448 * (but with non-standard args...) 449 */ 450 451 /* 452 * String representation for RPC. 453 */ 454 struct xdr_string { 455 u_int32_t len; /* length without null or padding */ 456 char data[4]; /* data (longer, of course) */ 457 /* data is padded to a long-word boundary */ 458 }; 459 460 struct mbuf * 461 xdr_string_encode(char *str, 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_getl(mlen, MB_WAIT, MT_DATA, 0, NULL); 475 xs = mtod(m, struct xdr_string *); 476 m->m_len = mlen; 477 xs->len = txdr_unsigned(len); 478 bcopy(str, xs->data, len); 479 return (m); 480 } 481