1 /* $NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-4-Clause 5 * 6 * Copyright (c) 1995 Gordon Ross, Adam Glass 7 * Copyright (c) 1992 Regents of the University of California. 8 * All rights reserved. 9 * 10 * This software was developed by the Computer Systems Engineering group 11 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 12 * contributed to Berkeley. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. All advertising materials mentioning features or use of this software 23 * must display the following acknowledgement: 24 * This product includes software developed by the University of 25 * California, Lawrence Berkeley Laboratory and its contributors. 26 * 4. Neither the name of the University nor the names of its contributors 27 * may be used to endorse or promote products derived from this software 28 * without specific prior written permission. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 33 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 40 * SUCH DAMAGE. 41 * 42 * partially based on: 43 * libnetboot/rpc.c 44 * @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL) 45 */ 46 47 #include <sys/cdefs.h> 48 __FBSDID("$FreeBSD$"); 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/jail.h> 53 #include <sys/malloc.h> 54 #include <sys/mbuf.h> 55 #include <sys/proc.h> 56 #include <sys/socket.h> 57 #include <sys/socketvar.h> 58 #include <sys/uio.h> 59 60 #include <net/if.h> 61 #include <net/vnet.h> 62 63 #include <netinet/in.h> 64 65 #include <rpc/types.h> 66 #include <rpc/auth.h> 67 #include <rpc/rpc_msg.h> 68 #include <nfs/krpc.h> 69 #include <nfs/xdr_subs.h> 70 71 /* 72 * Kernel support for Sun RPC 73 * 74 * Used currently for bootstrapping in nfs diskless configurations. 75 */ 76 77 /* 78 * Generic RPC headers 79 */ 80 81 struct auth_info { 82 u_int32_t authtype; /* auth type */ 83 u_int32_t authlen; /* auth length */ 84 }; 85 86 struct auth_unix { 87 int32_t ua_time; 88 int32_t ua_hostname; /* null */ 89 int32_t ua_uid; 90 int32_t ua_gid; 91 int32_t ua_gidlist; /* null */ 92 }; 93 94 struct krpc_call { 95 u_int32_t rp_xid; /* request transaction id */ 96 int32_t rp_direction; /* call direction (0) */ 97 u_int32_t rp_rpcvers; /* rpc version (2) */ 98 u_int32_t rp_prog; /* program */ 99 u_int32_t rp_vers; /* version */ 100 u_int32_t rp_proc; /* procedure */ 101 struct auth_info rpc_auth; 102 struct auth_unix rpc_unix; 103 struct auth_info rpc_verf; 104 }; 105 106 struct krpc_reply { 107 u_int32_t rp_xid; /* request transaction id */ 108 int32_t rp_direction; /* call direction (1) */ 109 int32_t rp_astatus; /* accept status (0: accepted) */ 110 union { 111 u_int32_t rpu_errno; 112 struct { 113 struct auth_info rok_auth; 114 u_int32_t rok_status; 115 } rpu_rok; 116 } rp_u; 117 }; 118 #define rp_errno rp_u.rpu_errno 119 #define rp_auth rp_u.rpu_rok.rok_auth 120 #define rp_status rp_u.rpu_rok.rok_status 121 122 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 123 124 /* 125 * What is the longest we will wait before re-sending a request? 126 * Note this is also the frequency of "RPC timeout" messages. 127 * The re-send loop count sup linearly to this maximum, so the 128 * first complaint will happen after (1+2+3+4+5)=15 seconds. 129 */ 130 #define MAX_RESEND_DELAY 5 /* seconds */ 131 132 /* 133 * Call portmap to lookup a port number for a particular rpc program 134 * Returns non-zero error on failure. 135 */ 136 int 137 krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp, 138 struct thread *td) 139 { 140 struct sdata { 141 u_int32_t prog; /* call program */ 142 u_int32_t vers; /* call version */ 143 u_int32_t proto; /* call protocol */ 144 u_int32_t port; /* call port (unused) */ 145 } *sdata; 146 struct rdata { 147 u_int16_t pad; 148 u_int16_t port; 149 } *rdata; 150 struct mbuf *m; 151 int error; 152 153 /* The portmapper port is fixed. */ 154 if (prog == PMAPPROG) { 155 *portp = htons(PMAPPORT); 156 return 0; 157 } 158 159 m = m_get(M_WAITOK, MT_DATA); 160 sdata = mtod(m, struct sdata *); 161 m->m_len = sizeof(*sdata); 162 163 /* Do the RPC to get it. */ 164 sdata->prog = txdr_unsigned(prog); 165 sdata->vers = txdr_unsigned(vers); 166 sdata->proto = txdr_unsigned(IPPROTO_UDP); 167 sdata->port = 0; 168 169 sin->sin_port = htons(PMAPPORT); 170 error = krpc_call(sin, PMAPPROG, PMAPVERS, 171 PMAPPROC_GETPORT, &m, NULL, td); 172 if (error) 173 return error; 174 175 if (m->m_len < sizeof(*rdata)) { 176 m = m_pullup(m, sizeof(*rdata)); 177 if (m == NULL) 178 return ENOBUFS; 179 } 180 rdata = mtod(m, struct rdata *); 181 *portp = rdata->port; 182 183 m_freem(m); 184 return 0; 185 } 186 187 /* 188 * Do a remote procedure call (RPC) and wait for its reply. 189 * If from_p is non-null, then we are doing broadcast, and 190 * the address from whence the response came is saved there. 191 */ 192 int 193 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 194 struct mbuf **data, struct sockaddr **from_p, struct thread *td) 195 { 196 struct socket *so; 197 struct sockaddr_in *sin, ssin; 198 struct sockaddr *from; 199 struct mbuf *m, *mhead; 200 struct krpc_call *call; 201 struct krpc_reply *reply; 202 struct sockopt sopt; 203 struct timeval tv; 204 struct uio auio; 205 int error, rcvflg, timo, secs, len; 206 static u_int32_t xid = ~0xFF; 207 u_int16_t tport; 208 u_int32_t saddr; 209 210 /* 211 * Validate address family. 212 * Sorry, this is INET specific... 213 */ 214 if (sa->sin_family != AF_INET) 215 return (EAFNOSUPPORT); 216 217 /* Free at end if not null. */ 218 mhead = NULL; 219 from = NULL; 220 221 /* 222 * Create socket and set its receive timeout. 223 */ 224 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td->td_ucred, td))) 225 return error; 226 227 tv.tv_sec = 1; 228 tv.tv_usec = 0; 229 bzero(&sopt, sizeof sopt); 230 sopt.sopt_dir = SOPT_SET; 231 sopt.sopt_level = SOL_SOCKET; 232 sopt.sopt_name = SO_RCVTIMEO; 233 sopt.sopt_val = &tv; 234 sopt.sopt_valsize = sizeof tv; 235 236 if ((error = sosetopt(so, &sopt)) != 0) 237 goto out; 238 239 /* 240 * Enable broadcast if necessary. 241 */ 242 if (from_p) { 243 int on = 1; 244 sopt.sopt_name = SO_BROADCAST; 245 sopt.sopt_val = &on; 246 sopt.sopt_valsize = sizeof on; 247 if ((error = sosetopt(so, &sopt)) != 0) 248 goto out; 249 } 250 251 /* 252 * Bind the local endpoint to a reserved port, 253 * because some NFS servers refuse requests from 254 * non-reserved (non-privileged) ports. 255 */ 256 sin = &ssin; 257 bzero(sin, sizeof *sin); 258 sin->sin_len = sizeof(*sin); 259 sin->sin_family = AF_INET; 260 sin->sin_addr.s_addr = INADDR_ANY; 261 tport = IPPORT_RESERVED; 262 do { 263 tport--; 264 sin->sin_port = htons(tport); 265 error = sobind(so, (struct sockaddr *)sin, td); 266 } while (error == EADDRINUSE && 267 tport > IPPORT_RESERVED / 2); 268 if (error) { 269 printf("bind failed\n"); 270 goto out; 271 } 272 273 /* 274 * Setup socket address for the server. 275 */ 276 277 /* 278 * Prepend RPC message header. 279 */ 280 mhead = m_gethdr(M_WAITOK, MT_DATA); 281 mhead->m_next = *data; 282 call = mtod(mhead, struct krpc_call *); 283 mhead->m_len = sizeof(*call); 284 bzero((caddr_t)call, sizeof(*call)); 285 /* rpc_call part */ 286 xid++; 287 call->rp_xid = txdr_unsigned(xid); 288 /* call->rp_direction = 0; */ 289 call->rp_rpcvers = txdr_unsigned(2); 290 call->rp_prog = txdr_unsigned(prog); 291 call->rp_vers = txdr_unsigned(vers); 292 call->rp_proc = txdr_unsigned(func); 293 /* rpc_auth part (auth_unix as root) */ 294 call->rpc_auth.authtype = txdr_unsigned(AUTH_UNIX); 295 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix)); 296 /* rpc_verf part (auth_null) */ 297 call->rpc_verf.authtype = 0; 298 call->rpc_verf.authlen = 0; 299 300 /* 301 * Setup packet header 302 */ 303 m_fixhdr(mhead); 304 mhead->m_pkthdr.rcvif = NULL; 305 306 /* 307 * Send it, repeatedly, until a reply is received, 308 * but delay each re-send by an increasing amount. 309 * If the delay hits the maximum, start complaining. 310 */ 311 timo = 0; 312 for (;;) { 313 /* Send RPC request (or re-send). */ 314 m = m_copym(mhead, 0, M_COPYALL, M_WAITOK); 315 error = sosend(so, (struct sockaddr *)sa, NULL, m, 316 NULL, 0, td); 317 if (error) { 318 printf("krpc_call: sosend: %d\n", error); 319 goto out; 320 } 321 m = NULL; 322 323 /* Determine new timeout. */ 324 if (timo < MAX_RESEND_DELAY) 325 timo++; 326 else { 327 saddr = ntohl(sa->sin_addr.s_addr); 328 printf("RPC timeout for server %d.%d.%d.%d\n", 329 (saddr >> 24) & 255, 330 (saddr >> 16) & 255, 331 (saddr >> 8) & 255, 332 saddr & 255); 333 } 334 335 /* 336 * Wait for up to timo seconds for a reply. 337 * The socket receive timeout was set to 1 second. 338 */ 339 secs = timo; 340 while (secs > 0) { 341 if (from) { 342 free(from, M_SONAME); 343 from = NULL; 344 } 345 if (m) { 346 m_freem(m); 347 m = NULL; 348 } 349 bzero(&auio, sizeof(auio)); 350 auio.uio_resid = len = 1<<16; 351 rcvflg = 0; 352 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg); 353 if (error == EWOULDBLOCK) { 354 secs--; 355 continue; 356 } 357 if (error) 358 goto out; 359 len -= auio.uio_resid; 360 361 /* Does the reply contain at least a header? */ 362 if (len < MIN_REPLY_HDR) 363 continue; 364 if (m->m_len < MIN_REPLY_HDR) 365 continue; 366 reply = mtod(m, struct krpc_reply *); 367 368 /* Is it the right reply? */ 369 if (reply->rp_direction != txdr_unsigned(REPLY)) 370 continue; 371 372 if (reply->rp_xid != txdr_unsigned(xid)) 373 continue; 374 375 /* Was RPC accepted? (authorization OK) */ 376 if (reply->rp_astatus != 0) { 377 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 378 printf("rpc denied, error=%d\n", error); 379 continue; 380 } 381 382 /* Did the call succeed? */ 383 if (reply->rp_status != 0) { 384 error = fxdr_unsigned(u_int32_t, reply->rp_status); 385 if (error == PROG_MISMATCH) { 386 error = EBADRPC; 387 goto out; 388 } 389 printf("rpc denied, status=%d\n", error); 390 continue; 391 } 392 393 goto gotreply; /* break two levels */ 394 395 } /* while secs */ 396 } /* forever send/receive */ 397 398 error = ETIMEDOUT; 399 goto out; 400 401 gotreply: 402 403 /* 404 * Get RPC reply header into first mbuf, 405 * get its length, then strip it off. 406 */ 407 len = sizeof(*reply); 408 if (m->m_len < len) { 409 m = m_pullup(m, len); 410 if (m == NULL) { 411 error = ENOBUFS; 412 goto out; 413 } 414 } 415 reply = mtod(m, struct krpc_reply *); 416 if (reply->rp_auth.authtype != 0) { 417 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 418 len = (len + 3) & ~3; /* XXX? */ 419 } 420 m_adj(m, len); 421 422 /* result */ 423 *data = m; 424 if (from_p) { 425 *from_p = from; 426 from = NULL; 427 } 428 429 out: 430 if (mhead) m_freem(mhead); 431 if (from) free(from, M_SONAME); 432 soclose(so); 433 return error; 434 } 435 436 /* 437 * eXternal Data Representation routines. 438 * (but with non-standard args...) 439 */ 440 441 /* 442 * String representation for RPC. 443 */ 444 struct xdr_string { 445 u_int32_t len; /* length without null or padding */ 446 char data[4]; /* data (longer, of course) */ 447 /* data is padded to a long-word boundary */ 448 }; 449 450 struct mbuf * 451 xdr_string_encode(char *str, int len) 452 { 453 struct mbuf *m; 454 struct xdr_string *xs; 455 int dlen; /* padded string length */ 456 int mlen; /* message length */ 457 458 dlen = (len + 3) & ~3; 459 mlen = dlen + 4; 460 461 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 462 return (NULL); 463 464 m = m_get2(mlen, M_WAITOK, MT_DATA, 0); 465 xs = mtod(m, struct xdr_string *); 466 m->m_len = mlen; 467 xs->len = txdr_unsigned(len); 468 bcopy(str, xs->data, len); 469 return (m); 470 } 471