1 /* $OpenBSD: krpc_subr.c,v 1.22 2013/11/11 09:15:35 mpi Exp $ */ 2 /* $NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd 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/conf.h> 49 #include <sys/ioctl.h> 50 #include <sys/proc.h> 51 #include <sys/mount.h> 52 #include <sys/mbuf.h> 53 #include <sys/reboot.h> 54 #include <sys/socket.h> 55 #include <sys/socketvar.h> 56 57 #include <net/if.h> 58 #include <netinet/in.h> 59 60 #include <nfs/rpcv2.h> 61 #include <nfs/krpc.h> 62 #include <nfs/xdr_subs.h> 63 #include <dev/rndvar.h> 64 #include <crypto/idgen.h> 65 66 /* 67 * Kernel support for Sun RPC 68 * 69 * Used currently for bootstrapping in nfs diskless configurations. 70 */ 71 72 /* 73 * Generic RPC headers 74 */ 75 76 struct auth_info { 77 u_int32_t authtype; /* auth type */ 78 u_int32_t authlen; /* auth length */ 79 }; 80 81 struct auth_unix { 82 int32_t ua_time; 83 int32_t ua_hostname; /* null */ 84 int32_t ua_uid; 85 int32_t ua_gid; 86 int32_t ua_gidlist; /* null */ 87 }; 88 89 struct rpc_call { 90 u_int32_t rp_xid; /* request transaction id */ 91 int32_t rp_direction; /* call direction (0) */ 92 u_int32_t rp_rpcvers; /* rpc version (2) */ 93 u_int32_t rp_prog; /* program */ 94 u_int32_t rp_vers; /* version */ 95 u_int32_t rp_proc; /* procedure */ 96 struct auth_info rpc_auth; 97 struct auth_unix rpc_unix; 98 struct auth_info rpc_verf; 99 }; 100 101 struct rpc_reply { 102 u_int32_t rp_xid; /* request transaction id */ 103 int32_t rp_direction; /* call direction (1) */ 104 int32_t rp_astatus; /* accept status (0: accepted) */ 105 union { 106 u_int32_t rpu_errno; 107 struct { 108 struct auth_info rok_auth; 109 u_int32_t rok_status; 110 } rpu_rok; 111 } rp_u; 112 }; 113 #define rp_errno rp_u.rpu_errno 114 #define rp_auth rp_u.rpu_rok.rok_auth 115 #define rp_status rp_u.rpu_rok.rok_status 116 117 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 118 119 u_int32_t krpc_get_xid(void); 120 121 /* 122 * Return an unpredictable XID. 123 */ 124 u_int32_t 125 krpc_get_xid(void) 126 { 127 static struct idgen32_ctx krpc_xid_ctx; 128 static int called = 0; 129 130 if (!called) { 131 called = 1; 132 idgen32_init(&krpc_xid_ctx); 133 } 134 return idgen32(&krpc_xid_ctx); 135 } 136 137 /* 138 * What is the longest we will wait before re-sending a request? 139 * Note this is also the frequency of "RPC timeout" messages. 140 * The re-send loop count sup linearly to this maximum, so the 141 * first complaint will happen after (1+2+3+4+5)=15 seconds. 142 */ 143 #define MAX_RESEND_DELAY 5 /* seconds */ 144 145 /* 146 * Call portmap to lookup a port number for a particular rpc program 147 * Returns non-zero error on failure. 148 */ 149 int 150 krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp) 151 { 152 struct sdata { 153 u_int32_t prog; /* call program */ 154 u_int32_t vers; /* call version */ 155 u_int32_t proto; /* call protocol */ 156 u_int32_t port; /* call port (unused) */ 157 } *sdata; 158 struct rdata { 159 u_int16_t pad; 160 u_int16_t port; 161 } *rdata; 162 struct mbuf *m; 163 int error; 164 165 /* The portmapper port is fixed. */ 166 if (prog == PMAPPROG) { 167 *portp = htons(PMAPPORT); 168 return 0; 169 } 170 171 m = m_get(M_WAIT, MT_DATA); 172 sdata = mtod(m, struct sdata *); 173 m->m_len = sizeof(*sdata); 174 175 /* Do the RPC to get it. */ 176 sdata->prog = txdr_unsigned(prog); 177 sdata->vers = txdr_unsigned(vers); 178 sdata->proto = txdr_unsigned(IPPROTO_UDP); 179 sdata->port = 0; 180 181 sin->sin_port = htons(PMAPPORT); 182 error = krpc_call(sin, PMAPPROG, PMAPVERS, 183 PMAPPROC_GETPORT, &m, NULL, -1); 184 if (error) 185 return error; 186 187 if (m->m_len < sizeof(*rdata)) { 188 m = m_pullup(m, sizeof(*rdata)); 189 if (m == NULL) 190 return ENOBUFS; 191 } 192 rdata = mtod(m, struct rdata *); 193 *portp = rdata->port; 194 195 m_freem(m); 196 return 0; 197 } 198 199 /* 200 * Do a remote procedure call (RPC) and wait for its reply. 201 * If from_p is non-null, then we are doing broadcast, and 202 * the address from whence the response came is saved there. 203 * data: input/output 204 * from_p: output 205 */ 206 int 207 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 208 struct mbuf **data, struct mbuf **from_p, int retries) 209 { 210 struct socket *so; 211 struct sockaddr_in *sin; 212 struct mbuf *m, *nam, *mhead, *from, *mopt; 213 struct rpc_call *call; 214 struct rpc_reply *reply; 215 struct uio auio; 216 int error, rcvflg, timo, secs, len; 217 static u_int32_t xid = 0; 218 char addr[INET_ADDRSTRLEN]; 219 int *ip; 220 struct timeval tv; 221 222 /* 223 * Validate address family. 224 * Sorry, this is INET specific... 225 */ 226 if (sa->sin_family != AF_INET) 227 return (EAFNOSUPPORT); 228 229 /* Free at end if not null. */ 230 nam = mhead = NULL; 231 from = NULL; 232 233 /* 234 * Create socket and set its receive timeout. 235 */ 236 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0))) 237 goto out; 238 239 m = m_get(M_WAIT, MT_SOOPTS); 240 tv.tv_sec = 1; 241 tv.tv_usec = 0; 242 memcpy(mtod(m, struct timeval *), &tv, sizeof tv); 243 m->m_len = sizeof(tv); 244 if ((error = sosetopt(so, SOL_SOCKET, SO_RCVTIMEO, m))) 245 goto out; 246 247 /* 248 * Enable broadcast if necessary. 249 */ 250 if (from_p) { 251 int32_t *on; 252 m = m_get(M_WAIT, MT_SOOPTS); 253 on = mtod(m, int32_t *); 254 m->m_len = sizeof(*on); 255 *on = 1; 256 if ((error = sosetopt(so, SOL_SOCKET, SO_BROADCAST, m))) 257 goto out; 258 } 259 260 /* 261 * Bind the local endpoint to a reserved port, 262 * because some NFS servers refuse requests from 263 * non-reserved (non-privileged) ports. 264 */ 265 MGET(mopt, M_WAIT, MT_SOOPTS); 266 mopt->m_len = sizeof(int); 267 ip = mtod(mopt, int *); 268 *ip = IP_PORTRANGE_LOW; 269 error = sosetopt(so, IPPROTO_IP, IP_PORTRANGE, mopt); 270 if (error) 271 goto out; 272 273 MGET(m, M_WAIT, MT_SONAME); 274 sin = mtod(m, struct sockaddr_in *); 275 sin->sin_len = m->m_len = sizeof (struct sockaddr_in); 276 sin->sin_family = AF_INET; 277 sin->sin_addr.s_addr = INADDR_ANY; 278 sin->sin_port = htons(0); 279 error = sobind(so, m, &proc0); 280 m_freem(m); 281 if (error) { 282 printf("bind failed\n"); 283 goto out; 284 } 285 286 MGET(mopt, M_WAIT, MT_SOOPTS); 287 mopt->m_len = sizeof(int); 288 ip = mtod(mopt, int *); 289 *ip = IP_PORTRANGE_DEFAULT; 290 error = sosetopt(so, IPPROTO_IP, IP_PORTRANGE, mopt); 291 if (error) 292 goto out; 293 294 /* 295 * Setup socket address for the server. 296 */ 297 nam = m_get(M_WAIT, MT_SONAME); 298 sin = mtod(nam, struct sockaddr_in *); 299 bcopy((caddr_t)sa, (caddr_t)sin, (nam->m_len = sa->sin_len)); 300 301 /* 302 * Prepend RPC message header. 303 */ 304 mhead = m_gethdr(M_WAIT, MT_DATA); 305 mhead->m_next = *data; 306 call = mtod(mhead, struct rpc_call *); 307 mhead->m_len = sizeof(*call); 308 bzero((caddr_t)call, sizeof(*call)); 309 /* rpc_call part */ 310 xid = krpc_get_xid(); 311 call->rp_xid = txdr_unsigned(xid); 312 /* call->rp_direction = 0; */ 313 call->rp_rpcvers = txdr_unsigned(2); 314 call->rp_prog = txdr_unsigned(prog); 315 call->rp_vers = txdr_unsigned(vers); 316 call->rp_proc = txdr_unsigned(func); 317 /* rpc_auth part (auth_unix as root) */ 318 call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX); 319 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix)); 320 /* rpc_verf part (auth_null) */ 321 call->rpc_verf.authtype = 0; 322 call->rpc_verf.authlen = 0; 323 324 /* 325 * Setup packet header 326 */ 327 len = 0; 328 m = mhead; 329 while (m) { 330 len += m->m_len; 331 m = m->m_next; 332 } 333 mhead->m_pkthdr.len = len; 334 mhead->m_pkthdr.rcvif = NULL; 335 336 /* 337 * Send it, repeatedly, until a reply is received, 338 * but delay each re-send by an increasing amount. 339 * If the delay hits the maximum, start complaining. 340 */ 341 for (timo = 0; retries; retries--) { 342 /* Send RPC request (or re-send). */ 343 m = m_copym(mhead, 0, M_COPYALL, M_WAIT); 344 if (m == NULL) { 345 error = ENOBUFS; 346 goto out; 347 } 348 error = sosend(so, nam, NULL, m, NULL, 0); 349 if (error) { 350 printf("krpc_call: sosend: %d\n", error); 351 goto out; 352 } 353 m = NULL; 354 355 /* Determine new timeout. */ 356 if (timo < MAX_RESEND_DELAY) 357 timo++; 358 else 359 printf("RPC timeout for server %s (0x%x) prog %u\n", 360 inet_ntop(AF_INET, &sin->sin_addr, 361 addr, sizeof(addr)), 362 ntohl(sin->sin_addr.s_addr), prog); 363 364 /* 365 * Wait for up to timo seconds for a reply. 366 * The socket receive timeout was set to 1 second. 367 */ 368 secs = timo; 369 while (secs > 0) { 370 if (from) { 371 m_freem(from); 372 from = NULL; 373 } 374 if (m) { 375 m_freem(m); 376 m = NULL; 377 } 378 auio.uio_resid = len = 1<<16; 379 auio.uio_procp = NULL; 380 rcvflg = 0; 381 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg, 382 0); 383 if (error == EWOULDBLOCK) { 384 secs--; 385 continue; 386 } 387 if (error) 388 goto out; 389 len -= auio.uio_resid; 390 391 /* Does the reply contain at least a header? */ 392 if (len < MIN_REPLY_HDR) 393 continue; 394 if (m->m_len < MIN_REPLY_HDR) 395 continue; 396 reply = mtod(m, struct rpc_reply *); 397 398 /* Is it the right reply? */ 399 if (reply->rp_direction != txdr_unsigned(RPC_REPLY)) 400 continue; 401 402 if (reply->rp_xid != txdr_unsigned(xid)) 403 continue; 404 405 /* Was RPC accepted? (authorization OK) */ 406 if (reply->rp_astatus != 0) { 407 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 408 printf("rpc denied, error=%d\n", error); 409 continue; 410 } 411 412 /* Did the call succeed? */ 413 if (reply->rp_status != 0) { 414 error = fxdr_unsigned(u_int32_t, reply->rp_status); 415 printf("rpc denied, status=%d\n", error); 416 continue; 417 } 418 419 goto gotreply; /* break two levels */ 420 421 } /* while secs */ 422 } /* forever send/receive */ 423 424 error = ETIMEDOUT; 425 goto out; 426 427 gotreply: 428 429 /* 430 * Get RPC reply header into first mbuf, 431 * get its length, then strip it off. 432 */ 433 len = sizeof(*reply); 434 if (m->m_len < len) { 435 m = m_pullup(m, len); 436 if (m == NULL) { 437 error = ENOBUFS; 438 goto out; 439 } 440 } 441 reply = mtod(m, struct rpc_reply *); 442 if (reply->rp_auth.authtype != 0) { 443 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 444 len = (len + 3) & ~3; /* XXX? */ 445 } 446 m_adj(m, len); 447 448 /* result */ 449 *data = m; 450 if (from_p && error == 0) { 451 *from_p = from; 452 from = NULL; 453 } 454 455 out: 456 if (nam) m_freem(nam); 457 if (mhead) m_freem(mhead); 458 if (from) m_freem(from); 459 soclose(so); 460 return error; 461 } 462 463 /* 464 * eXternal Data Representation routines. 465 * (but with non-standard args...) 466 */ 467 468 /* 469 * String representation for RPC. 470 */ 471 struct xdr_string { 472 u_int32_t len; /* length without null or padding */ 473 char data[4]; /* data (longer, of course) */ 474 /* data is padded to a long-word boundary */ 475 }; 476 477 struct mbuf * 478 xdr_string_encode(char *str, int len) 479 { 480 struct mbuf *m; 481 struct xdr_string *xs; 482 int dlen; /* padded string length */ 483 int mlen; /* message length */ 484 485 dlen = (len + 3) & ~3; 486 mlen = dlen + 4; 487 488 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 489 return (NULL); 490 491 m = m_get(M_WAIT, MT_DATA); 492 if (mlen > MLEN) { 493 MCLGET(m, M_WAIT); 494 if ((m->m_flags & M_EXT) == 0) { 495 (void) m_free(m); /* There can be only one. */ 496 return (NULL); 497 } 498 } 499 xs = mtod(m, struct xdr_string *); 500 m->m_len = mlen; 501 xs->len = txdr_unsigned(len); 502 bcopy(str, xs->data, len); 503 return (m); 504 } 505 506 struct mbuf * 507 xdr_string_decode(struct mbuf *m, char *str, int *len_p) 508 { 509 struct xdr_string *xs; 510 int mlen; /* message length */ 511 int slen; /* string length */ 512 513 if (m->m_len < 4) { 514 m = m_pullup(m, 4); 515 if (m == NULL) 516 return (NULL); 517 } 518 xs = mtod(m, struct xdr_string *); 519 slen = fxdr_unsigned(u_int32_t, xs->len); 520 mlen = 4 + ((slen + 3) & ~3); 521 522 if (slen > *len_p) 523 slen = *len_p; 524 if (slen > m->m_pkthdr.len) { 525 m_freem(m); 526 return (NULL); 527 } 528 m_copydata(m, 4, slen, str); 529 m_adj(m, mlen); 530 531 str[slen] = '\0'; 532 *len_p = slen; 533 534 return (m); 535 } 536 537 538 /* 539 * Inet address in RPC messages 540 * (Note, really four ints, NOT chars. Blech.) 541 */ 542 struct xdr_inaddr { 543 u_int32_t atype; 544 u_int32_t addr[4]; 545 }; 546 547 struct mbuf * 548 xdr_inaddr_encode(struct in_addr *ia) 549 { 550 struct mbuf *m; 551 struct xdr_inaddr *xi; 552 u_int8_t *cp; 553 u_int32_t *ip; 554 555 m = m_get(M_WAIT, MT_DATA); 556 xi = mtod(m, struct xdr_inaddr *); 557 m->m_len = sizeof(*xi); 558 xi->atype = txdr_unsigned(1); 559 ip = xi->addr; 560 cp = (u_int8_t *)&ia->s_addr; 561 *ip++ = txdr_unsigned(*cp++); 562 *ip++ = txdr_unsigned(*cp++); 563 *ip++ = txdr_unsigned(*cp++); 564 *ip++ = txdr_unsigned(*cp++); 565 566 return (m); 567 } 568 569 struct mbuf * 570 xdr_inaddr_decode(struct mbuf *m, struct in_addr *ia) 571 { 572 struct xdr_inaddr *xi; 573 u_int8_t *cp; 574 u_int32_t *ip; 575 576 if (m->m_len < sizeof(*xi)) { 577 m = m_pullup(m, sizeof(*xi)); 578 if (m == NULL) 579 return (NULL); 580 } 581 xi = mtod(m, struct xdr_inaddr *); 582 if (xi->atype != txdr_unsigned(1)) { 583 ia->s_addr = INADDR_ANY; 584 goto out; 585 } 586 ip = xi->addr; 587 cp = (u_int8_t *)&ia->s_addr; 588 *cp++ = fxdr_unsigned(u_int8_t, *ip++); 589 *cp++ = fxdr_unsigned(u_int8_t, *ip++); 590 *cp++ = fxdr_unsigned(u_int8_t, *ip++); 591 *cp++ = fxdr_unsigned(u_int8_t, *ip++); 592 593 out: 594 m_adj(m, sizeof(*xi)); 595 return (m); 596 } 597