1 /* $NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd Exp $ */ 2 /* $Id: krpc_subr.c,v 1.11 1998/08/23 03:07:16 wollman 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; 207 208 /* 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 nam = 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, procp))) 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, procp); 263 } while (error == EADDRINUSE && 264 tport > IPPORT_RESERVED / 2); 265 if (error) { 266 printf("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(M_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 xid++; 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_WAIT); 318 if (m == NULL) { 319 error = ENOBUFS; 320 goto out; 321 } 322 error = sosend(so, (struct sockaddr *)sa, NULL, m, 323 NULL, 0, 0); 324 if (error) { 325 printf("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 printf("RPC timeout for server 0x%lx\n", 335 (u_long)ntohl(sa->sin_addr.s_addr)); 336 337 /* 338 * Wait for up to timo seconds for a reply. 339 * The socket receive timeout was set to 1 second. 340 */ 341 secs = timo; 342 while (secs > 0) { 343 if (from) { 344 FREE(from, M_SONAME); 345 from = NULL; 346 } 347 if (m) { 348 m_freem(m); 349 m = NULL; 350 } 351 bzero(&auio,sizeof(auio)); 352 auio.uio_resid = len = 1<<16; 353 rcvflg = 0; 354 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg); 355 if (error == EWOULDBLOCK) { 356 secs--; 357 continue; 358 } 359 if (error) 360 goto out; 361 len -= auio.uio_resid; 362 363 /* Does the reply contain at least a header? */ 364 if (len < MIN_REPLY_HDR) 365 continue; 366 if (m->m_len < MIN_REPLY_HDR) 367 continue; 368 reply = mtod(m, struct rpc_reply *); 369 370 /* Is it the right reply? */ 371 if (reply->rp_direction != txdr_unsigned(RPC_REPLY)) 372 continue; 373 374 if (reply->rp_xid != txdr_unsigned(xid)) 375 continue; 376 377 /* Was RPC accepted? (authorization OK) */ 378 if (reply->rp_astatus != 0) { 379 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 380 printf("rpc denied, error=%d\n", error); 381 continue; 382 } 383 384 /* Did the call succeed? */ 385 if (reply->rp_status != 0) { 386 error = fxdr_unsigned(u_int32_t, reply->rp_status); 387 if (error == RPC_PROGMISMATCH) { 388 error = EBADRPC; 389 goto out; 390 } 391 printf("rpc denied, status=%d\n", error); 392 continue; 393 } 394 395 goto gotreply; /* break two levels */ 396 397 } /* while secs */ 398 } /* forever send/receive */ 399 400 error = ETIMEDOUT; 401 goto out; 402 403 gotreply: 404 405 /* 406 * Get RPC reply header into first mbuf, 407 * get its length, then strip it off. 408 */ 409 len = sizeof(*reply); 410 if (m->m_len < len) { 411 m = m_pullup(m, len); 412 if (m == NULL) { 413 error = ENOBUFS; 414 goto out; 415 } 416 } 417 reply = mtod(m, struct rpc_reply *); 418 if (reply->rp_auth.authtype != 0) { 419 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 420 len = (len + 3) & ~3; /* XXX? */ 421 } 422 m_adj(m, len); 423 424 /* result */ 425 *data = m; 426 if (from_p) { 427 *from_p = from; 428 from = NULL; 429 } 430 431 out: 432 if (mhead) m_freem(mhead); 433 if (from) free(from, M_SONAME); 434 soclose(so); 435 return error; 436 } 437 438 /* 439 * eXternal Data Representation routines. 440 * (but with non-standard args...) 441 */ 442 443 /* 444 * String representation for RPC. 445 */ 446 struct xdr_string { 447 u_int32_t len; /* length without null or padding */ 448 char data[4]; /* data (longer, of course) */ 449 /* data is padded to a long-word boundary */ 450 }; 451 452 struct mbuf * 453 xdr_string_encode(str, len) 454 char *str; 455 int len; 456 { 457 struct mbuf *m; 458 struct xdr_string *xs; 459 int dlen; /* padded string length */ 460 int mlen; /* message length */ 461 462 dlen = (len + 3) & ~3; 463 mlen = dlen + 4; 464 465 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 466 return (NULL); 467 468 m = m_get(M_WAIT, MT_DATA); 469 if (mlen > MLEN) { 470 MCLGET(m, M_WAIT); 471 if ((m->m_flags & M_EXT) == 0) { 472 (void) m_free(m); /* There can be only one. */ 473 return (NULL); 474 } 475 } 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