1 /* $NetBSD: krpc_subr.c,v 1.8 1995/04/24 21:55:05 gwr Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Gordon Ross, Adam Glass 5 * Copyright (c) 1992 Regents of the University of California. 6 * All rights reserved. 7 * 8 * This software was developed by the Computer Systems Engineering group 9 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 10 * contributed to Berkeley. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Lawrence Berkeley Laboratory and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * partially based on: 41 * libnetboot/rpc.c 42 * @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL) 43 */ 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/conf.h> 48 #include <sys/ioctl.h> 49 #include <sys/proc.h> 50 #include <sys/mount.h> 51 #include <sys/mbuf.h> 52 #include <sys/reboot.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 56 #include <net/if.h> 57 #include <netinet/in.h> 58 59 #include <nfs/rpcv2.h> 60 #include <nfs/krpc.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 int32_t rp_atype; /* auth type */ 74 u_int32_t rp_alen; /* auth length */ 75 }; 76 77 struct rpc_call { 78 u_int32_t rp_xid; /* request transaction id */ 79 int32_t rp_direction; /* call direction (0) */ 80 u_int32_t rp_rpcvers; /* rpc version (2) */ 81 u_int32_t rp_prog; /* program */ 82 u_int32_t rp_vers; /* version */ 83 u_int32_t rp_proc; /* procedure */ 84 struct auth_info rp_auth; 85 struct auth_info rp_verf; 86 }; 87 88 struct rpc_reply { 89 u_int32_t rp_xid; /* request transaction id */ 90 int32_t rp_direction; /* call direction (1) */ 91 int32_t rp_astatus; /* accept status (0: accepted) */ 92 union { 93 u_int32_t rpu_errno; 94 struct { 95 struct auth_info rp_auth; 96 u_int32_t rp_rstatus; /* reply status */ 97 } rpu_ok; 98 } rp_u; 99 }; 100 101 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 102 103 /* 104 * What is the longest we will wait before re-sending a request? 105 * Note this is also the frequency of "RPC timeout" messages. 106 * The re-send loop count sup linearly to this maximum, so the 107 * first complaint will happen after (1+2+3+4+5)=15 seconds. 108 */ 109 #define MAX_RESEND_DELAY 5 /* seconds */ 110 111 /* 112 * Call portmap to lookup a port number for a particular rpc program 113 * Returns non-zero error on failure. 114 */ 115 int 116 krpc_portmap(sin, prog, vers, portp) 117 struct sockaddr_in *sin; /* server address */ 118 u_int prog, vers; /* host order */ 119 u_int16_t *portp; /* network order */ 120 { 121 struct sdata { 122 u_int32_t prog; /* call program */ 123 u_int32_t vers; /* call version */ 124 u_int32_t proto; /* call protocol */ 125 u_int32_t port; /* call port (unused) */ 126 } *sdata; 127 struct rdata { 128 u_int16_t pad; 129 u_int16_t port; 130 } *rdata; 131 struct mbuf *m; 132 int error; 133 134 /* The portmapper port is fixed. */ 135 if (prog == PMAPPROG) { 136 *portp = htons(PMAPPORT); 137 return 0; 138 } 139 140 m = m_get(M_WAIT, MT_DATA); 141 if (m == NULL) 142 return ENOBUFS; 143 sdata = mtod(m, struct sdata *); 144 m->m_len = sizeof(*sdata); 145 146 /* Do the RPC to get it. */ 147 sdata->prog = htonl(prog); 148 sdata->vers = htonl(vers); 149 sdata->proto = htonl(IPPROTO_UDP); 150 sdata->port = 0; 151 152 sin->sin_port = htons(PMAPPORT); 153 error = krpc_call(sin, PMAPPROG, PMAPVERS, 154 PMAPPROC_GETPORT, &m, NULL); 155 if (error) 156 return error; 157 158 if (m->m_len < sizeof(*rdata)) { 159 m = m_pullup(m, sizeof(*rdata)); 160 if (m == NULL) 161 return ENOBUFS; 162 } 163 rdata = mtod(m, struct rdata *); 164 *portp = rdata->port; 165 166 m_freem(m); 167 return 0; 168 } 169 170 /* 171 * Do a remote procedure call (RPC) and wait for its reply. 172 * If from_p is non-null, then we are doing broadcast, and 173 * the address from whence the response came is saved there. 174 */ 175 int 176 krpc_call(sa, prog, vers, func, data, from_p) 177 struct sockaddr_in *sa; 178 u_int prog, vers, func; 179 struct mbuf **data; /* input/output */ 180 struct mbuf **from_p; /* output */ 181 { 182 struct socket *so; 183 struct sockaddr_in *sin; 184 struct mbuf *m, *nam, *mhead, *from; 185 struct rpc_call *call; 186 struct rpc_reply *reply; 187 struct uio auio; 188 int error, rcvflg, timo, secs, len; 189 static u_int32_t xid = ~0xFF; 190 u_int tport; 191 192 /* 193 * Validate address family. 194 * Sorry, this is INET specific... 195 */ 196 if (sa->sin_family != AF_INET) 197 return (EAFNOSUPPORT); 198 199 /* Free at end if not null. */ 200 nam = mhead = NULL; 201 from = NULL; 202 203 /* 204 * Create socket and set its recieve timeout. 205 */ 206 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0))) 207 goto out; 208 209 m = m_get(M_WAIT, MT_SOOPTS); 210 if (m == NULL) { 211 error = ENOBUFS; 212 goto out; 213 } else { 214 struct timeval *tv; 215 tv = mtod(m, struct timeval *); 216 m->m_len = sizeof(*tv); 217 tv->tv_sec = 1; 218 tv->tv_usec = 0; 219 if ((error = sosetopt(so, SOL_SOCKET, SO_RCVTIMEO, m))) 220 goto out; 221 } 222 223 /* 224 * Enable broadcast if necessary. 225 */ 226 if (from_p) { 227 int *on; 228 m = m_get(M_WAIT, MT_SOOPTS); 229 if (m == NULL) { 230 error = ENOBUFS; 231 goto out; 232 } 233 on = mtod(m, int *); 234 m->m_len = sizeof(*on); 235 *on = 1; 236 if ((error = sosetopt(so, SOL_SOCKET, SO_BROADCAST, m))) 237 goto out; 238 } 239 240 /* 241 * Bind the local endpoint to a reserved port, 242 * because some NFS servers refuse requests from 243 * non-reserved (non-privileged) ports. 244 */ 245 m = m_getclr(M_WAIT, MT_SONAME); 246 sin = mtod(m, struct sockaddr_in *); 247 sin->sin_len = m->m_len = sizeof(*sin); 248 sin->sin_family = AF_INET; 249 sin->sin_addr.s_addr = INADDR_ANY; 250 tport = IPPORT_RESERVED; 251 do { 252 tport--; 253 sin->sin_port = htons(tport); 254 error = sobind(so, m); 255 } while (error == EADDRINUSE && 256 tport > IPPORT_RESERVED / 2); 257 m_freem(m); 258 if (error) { 259 printf("bind failed\n"); 260 goto out; 261 } 262 263 /* 264 * Setup socket address for the server. 265 */ 266 nam = m_get(M_WAIT, MT_SONAME); 267 if (nam == NULL) { 268 error = ENOBUFS; 269 goto out; 270 } 271 sin = mtod(nam, struct sockaddr_in *); 272 bcopy((caddr_t)sa, (caddr_t)sin, 273 (nam->m_len = sa->sin_len)); 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 xid++; 284 call->rp_xid = htonl(xid); 285 /* call->rp_direction = 0; */ 286 call->rp_rpcvers = htonl(2); 287 call->rp_prog = htonl(prog); 288 call->rp_vers = htonl(vers); 289 call->rp_proc = htonl(func); 290 /* call->rp_auth = 0; */ 291 /* call->rp_verf = 0; */ 292 293 /* 294 * Setup packet header 295 */ 296 len = 0; 297 m = mhead; 298 while (m) { 299 len += m->m_len; 300 m = m->m_next; 301 } 302 mhead->m_pkthdr.len = len; 303 mhead->m_pkthdr.rcvif = NULL; 304 305 /* 306 * Send it, repeatedly, until a reply is received, 307 * but delay each re-send by an increasing amount. 308 * If the delay hits the maximum, start complaining. 309 */ 310 timo = 0; 311 for (;;) { 312 /* Send RPC request (or re-send). */ 313 m = m_copym(mhead, 0, M_COPYALL, M_WAIT); 314 if (m == NULL) { 315 error = ENOBUFS; 316 goto out; 317 } 318 error = sosend(so, nam, NULL, m, NULL, 0); 319 if (error) { 320 printf("krpc_call: sosend: %d\n", error); 321 goto out; 322 } 323 m = NULL; 324 325 /* Determine new timeout. */ 326 if (timo < MAX_RESEND_DELAY) 327 timo++; 328 else 329 printf("RPC timeout for server 0x%x\n", 330 ntohl(sin->sin_addr.s_addr)); 331 332 /* 333 * Wait for up to timo seconds for a reply. 334 * The socket receive timeout was set to 1 second. 335 */ 336 secs = timo; 337 while (secs > 0) { 338 if (from) { 339 m_freem(from); 340 from = NULL; 341 } 342 if (m) { 343 m_freem(m); 344 m = NULL; 345 } 346 auio.uio_resid = len = 1<<16; 347 rcvflg = 0; 348 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg); 349 if (error == EWOULDBLOCK) { 350 secs--; 351 continue; 352 } 353 if (error) 354 goto out; 355 len -= auio.uio_resid; 356 357 /* Does the reply contain at least a header? */ 358 if (len < MIN_REPLY_HDR) 359 continue; 360 if (m->m_len < MIN_REPLY_HDR) 361 continue; 362 reply = mtod(m, struct rpc_reply *); 363 364 /* Is it the right reply? */ 365 if (reply->rp_direction != htonl(RPC_REPLY)) 366 continue; 367 368 if (reply->rp_xid != htonl(xid)) 369 continue; 370 371 /* Was RPC accepted? (authorization OK) */ 372 if (reply->rp_astatus != 0) { 373 error = ntohl(reply->rp_u.rpu_errno); 374 printf("rpc denied, error=%d\n", error); 375 continue; 376 } 377 378 /* Did the call succeed? */ 379 if ((error = ntohl(reply->rp_u.rpu_ok.rp_rstatus)) != 0) { 380 printf("rpc status=%d\n", error); 381 continue; 382 } 383 384 goto gotreply; /* break two levels */ 385 386 } /* while secs */ 387 } /* forever send/receive */ 388 389 error = ETIMEDOUT; 390 goto out; 391 392 gotreply: 393 394 /* 395 * Get RPC reply header into first mbuf, 396 * get its length, then strip it off. 397 */ 398 len = sizeof(*reply); 399 if (m->m_len < len) { 400 m = m_pullup(m, len); 401 if (m == NULL) { 402 error = ENOBUFS; 403 goto out; 404 } 405 } 406 reply = mtod(m, struct rpc_reply *); 407 if (reply->rp_u.rpu_ok.rp_auth.rp_atype != 0) { 408 len += ntohl(reply->rp_u.rpu_ok.rp_auth.rp_alen); 409 len = (len + 3) & ~3; /* XXX? */ 410 } 411 m_adj(m, len); 412 413 /* result */ 414 *data = m; 415 if (from_p) { 416 *from_p = from; 417 from = NULL; 418 } 419 420 out: 421 if (nam) m_freem(nam); 422 if (mhead) m_freem(mhead); 423 if (from) m_freem(from); 424 soclose(so); 425 return error; 426 } 427 428 /* 429 * eXternal Data Representation routines. 430 * (but with non-standard args...) 431 */ 432 433 /* 434 * String representation for RPC. 435 */ 436 struct xdr_string { 437 u_int32_t len; /* length without null or padding */ 438 char data[4]; /* data (longer, of course) */ 439 /* data is padded to a long-word boundary */ 440 }; 441 442 struct mbuf * 443 xdr_string_encode(str, len) 444 char *str; 445 int len; 446 { 447 struct mbuf *m; 448 struct xdr_string *xs; 449 int dlen; /* padded string length */ 450 int mlen; /* message length */ 451 452 dlen = (len + 3) & ~3; 453 mlen = dlen + 4; 454 455 m = m_get(M_WAIT, MT_DATA); 456 if (mlen > MLEN) { 457 if (mlen > MCLBYTES) 458 return(NULL); 459 MCLGET(m, M_WAIT); 460 if (m == NULL) 461 return NULL; 462 } 463 xs = mtod(m, struct xdr_string *); 464 m->m_len = mlen; 465 xs->len = htonl(len); 466 bcopy(str, xs->data, len); 467 return (m); 468 } 469 470 struct mbuf * 471 xdr_string_decode(m, str, len_p) 472 struct mbuf *m; 473 char *str; 474 int *len_p; /* bufsize - 1 */ 475 { 476 struct xdr_string *xs; 477 int mlen; /* message length */ 478 int slen; /* string length */ 479 480 if (m->m_len < 4) { 481 m = m_pullup(m, 4); 482 if (m == NULL) 483 return (NULL); 484 } 485 xs = mtod(m, struct xdr_string *); 486 slen = ntohl(xs->len); 487 mlen = 4 + ((slen + 3) & ~3); 488 489 if (slen > *len_p) 490 slen = *len_p; 491 m_copydata(m, 4, slen, str); 492 m_adj(m, mlen); 493 494 str[slen] = '\0'; 495 *len_p = slen; 496 497 return (m); 498 } 499 500 501 /* 502 * Inet address in RPC messages 503 * (Note, really four ints, NOT chars. Blech.) 504 */ 505 struct xdr_inaddr { 506 u_int32_t atype; 507 int32_t addr[4]; 508 }; 509 510 struct mbuf * 511 xdr_inaddr_encode(ia) 512 struct in_addr *ia; /* already in network order */ 513 { 514 struct mbuf *m; 515 struct xdr_inaddr *xi; 516 u_char *cp; 517 int32_t *ip; 518 519 m = m_get(M_WAIT, MT_DATA); 520 xi = mtod(m, struct xdr_inaddr *); 521 m->m_len = sizeof(*xi); 522 xi->atype = htonl(1); 523 ip = xi->addr; 524 cp = (u_char *)&ia->s_addr; 525 *ip++ = *cp++; 526 *ip++ = *cp++; 527 *ip++ = *cp++; 528 *ip++ = *cp++; 529 530 return (m); 531 } 532 533 struct mbuf * 534 xdr_inaddr_decode(m, ia) 535 struct mbuf *m; 536 struct in_addr *ia; /* already in network order */ 537 { 538 struct xdr_inaddr *xi; 539 u_char *cp; 540 int32_t *ip; 541 542 if (m->m_len < sizeof(*xi)) { 543 m = m_pullup(m, sizeof(*xi)); 544 if (m == NULL) 545 return (NULL); 546 } 547 xi = mtod(m, struct xdr_inaddr *); 548 if (xi->atype != htonl(1)) { 549 ia->s_addr = INADDR_ANY; 550 goto out; 551 } 552 ip = xi->addr; 553 cp = (u_char *)&ia->s_addr; 554 *cp++ = *ip++; 555 *cp++ = *ip++; 556 *cp++ = *ip++; 557 *cp++ = *ip++; 558 559 out: 560 m_adj(m, sizeof(*xi)); 561 return (m); 562 } 563