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 */ 45 46 #include <sys/cdefs.h> 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/jail.h> 50 #include <sys/malloc.h> 51 #include <sys/mbuf.h> 52 #include <sys/proc.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 #include <sys/uio.h> 56 57 #include <net/if.h> 58 #include <net/vnet.h> 59 60 #include <netinet/in.h> 61 62 #include <rpc/types.h> 63 #include <rpc/auth.h> 64 #include <rpc/rpc_msg.h> 65 #include <nfs/krpc.h> 66 #include <nfs/xdr_subs.h> 67 68 /* 69 * Kernel support for Sun RPC 70 * 71 * Used currently for bootstrapping in nfs diskless configurations. 72 */ 73 74 /* 75 * Generic RPC headers 76 */ 77 78 struct auth_info { 79 u_int32_t authtype; /* auth type */ 80 u_int32_t authlen; /* auth length */ 81 }; 82 83 struct auth_unix { 84 int32_t ua_time; 85 int32_t ua_hostname; /* null */ 86 int32_t ua_uid; 87 int32_t ua_gid; 88 int32_t ua_gidlist; /* null */ 89 }; 90 91 struct krpc_call { 92 u_int32_t rp_xid; /* request transaction id */ 93 int32_t rp_direction; /* call direction (0) */ 94 u_int32_t rp_rpcvers; /* rpc version (2) */ 95 u_int32_t rp_prog; /* program */ 96 u_int32_t rp_vers; /* version */ 97 u_int32_t rp_proc; /* procedure */ 98 struct auth_info rpc_auth; 99 struct auth_unix rpc_unix; 100 struct auth_info rpc_verf; 101 }; 102 103 struct krpc_reply { 104 u_int32_t rp_xid; /* request transaction id */ 105 int32_t rp_direction; /* call direction (1) */ 106 int32_t rp_astatus; /* accept status (0: accepted) */ 107 union { 108 u_int32_t rpu_errno; 109 struct { 110 struct auth_info rok_auth; 111 u_int32_t rok_status; 112 } rpu_rok; 113 } rp_u; 114 }; 115 #define rp_errno rp_u.rpu_errno 116 #define rp_auth rp_u.rpu_rok.rok_auth 117 #define rp_status rp_u.rpu_rok.rok_status 118 119 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 120 121 /* 122 * What is the longest we will wait before re-sending a request? 123 * Note this is also the frequency of "RPC timeout" messages. 124 * The re-send loop count sup linearly to this maximum, so the 125 * first complaint will happen after (1+2+3+4+5)=15 seconds. 126 */ 127 #define MAX_RESEND_DELAY 5 /* seconds */ 128 129 /* 130 * Call portmap to lookup a port number for a particular rpc program 131 * Returns non-zero error on failure. 132 */ 133 int 134 krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp, 135 struct thread *td) 136 { 137 struct sdata { 138 u_int32_t prog; /* call program */ 139 u_int32_t vers; /* call version */ 140 u_int32_t proto; /* call protocol */ 141 u_int32_t port; /* call port (unused) */ 142 } *sdata; 143 struct rdata { 144 u_int16_t pad; 145 u_int16_t port; 146 } *rdata; 147 struct mbuf *m; 148 int error; 149 150 /* The portmapper port is fixed. */ 151 if (prog == PMAPPROG) { 152 *portp = htons(PMAPPORT); 153 return 0; 154 } 155 156 m = m_get(M_WAITOK, MT_DATA); 157 sdata = mtod(m, struct sdata *); 158 m->m_len = sizeof(*sdata); 159 160 /* Do the RPC to get it. */ 161 sdata->prog = txdr_unsigned(prog); 162 sdata->vers = txdr_unsigned(vers); 163 sdata->proto = txdr_unsigned(IPPROTO_UDP); 164 sdata->port = 0; 165 166 sin->sin_port = htons(PMAPPORT); 167 error = krpc_call(sin, PMAPPROG, PMAPVERS, 168 PMAPPROC_GETPORT, &m, NULL, td); 169 if (error) 170 return error; 171 172 if (m->m_len < sizeof(*rdata)) { 173 m = m_pullup(m, sizeof(*rdata)); 174 if (m == NULL) 175 return ENOBUFS; 176 } 177 rdata = mtod(m, struct rdata *); 178 *portp = rdata->port; 179 180 m_freem(m); 181 return 0; 182 } 183 184 /* 185 * Do a remote procedure call (RPC) and wait for its reply. 186 * If from_p is non-null, then we are doing broadcast, and 187 * the address from whence the response came is saved there. 188 */ 189 int 190 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 191 struct mbuf **data, struct sockaddr **from_p, 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 krpc_call *call; 198 struct krpc_reply *reply; 199 struct sockopt sopt; 200 struct timeval tv; 201 struct uio auio; 202 int error, rcvflg, timo, secs, len; 203 static u_int32_t xid = ~0xFF; 204 u_int16_t tport; 205 u_int32_t saddr; 206 207 /* 208 * Validate address family. 209 * Sorry, this is INET specific... 210 */ 211 if (sa->sin_family != AF_INET) 212 return (EAFNOSUPPORT); 213 214 /* Free at end if not null. */ 215 mhead = NULL; 216 from = NULL; 217 218 /* 219 * Create socket and set its receive timeout. 220 */ 221 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td->td_ucred, td))) 222 return error; 223 224 tv.tv_sec = 1; 225 tv.tv_usec = 0; 226 bzero(&sopt, sizeof sopt); 227 sopt.sopt_dir = SOPT_SET; 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 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_WAITOK, MT_DATA); 278 mhead->m_next = *data; 279 call = mtod(mhead, struct krpc_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(AUTH_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 m_fixhdr(mhead); 301 mhead->m_pkthdr.rcvif = NULL; 302 303 /* 304 * Send it, repeatedly, until a reply is received, 305 * but delay each re-send by an increasing amount. 306 * If the delay hits the maximum, start complaining. 307 */ 308 timo = 0; 309 for (;;) { 310 /* Send RPC request (or re-send). */ 311 m = m_copym(mhead, 0, M_COPYALL, M_WAITOK); 312 error = sosend(so, (struct sockaddr *)sa, NULL, m, 313 NULL, 0, td); 314 if (error) { 315 printf("krpc_call: sosend: %d\n", error); 316 goto out; 317 } 318 m = NULL; 319 320 /* Determine new timeout. */ 321 if (timo < MAX_RESEND_DELAY) 322 timo++; 323 else { 324 saddr = ntohl(sa->sin_addr.s_addr); 325 printf("RPC timeout for server %d.%d.%d.%d\n", 326 (saddr >> 24) & 255, 327 (saddr >> 16) & 255, 328 (saddr >> 8) & 255, 329 saddr & 255); 330 } 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 free(from, M_SONAME); 340 from = NULL; 341 } 342 if (m) { 343 m_freem(m); 344 m = NULL; 345 } 346 bzero(&auio, sizeof(auio)); 347 auio.uio_resid = len = 1<<16; 348 rcvflg = 0; 349 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg); 350 if (error == EWOULDBLOCK) { 351 secs--; 352 continue; 353 } 354 if (error) 355 goto out; 356 len -= auio.uio_resid; 357 358 /* Does the reply contain at least a header? */ 359 if (len < MIN_REPLY_HDR) 360 continue; 361 if (m->m_len < MIN_REPLY_HDR) 362 continue; 363 reply = mtod(m, struct krpc_reply *); 364 365 /* Is it the right reply? */ 366 if (reply->rp_direction != txdr_unsigned(REPLY)) 367 continue; 368 369 if (reply->rp_xid != txdr_unsigned(xid)) 370 continue; 371 372 /* Was RPC accepted? (authorization OK) */ 373 if (reply->rp_astatus != 0) { 374 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 375 printf("rpc denied, error=%d\n", error); 376 continue; 377 } 378 379 /* Did the call succeed? */ 380 if (reply->rp_status != 0) { 381 error = fxdr_unsigned(u_int32_t, reply->rp_status); 382 if (error == PROG_MISMATCH) { 383 error = EBADRPC; 384 goto out; 385 } 386 printf("rpc denied, status=%d\n", error); 387 continue; 388 } 389 390 goto gotreply; /* break two levels */ 391 392 } /* while secs */ 393 } /* forever send/receive */ 394 395 error = ETIMEDOUT; 396 goto out; 397 398 gotreply: 399 400 /* 401 * Get RPC reply header into first mbuf, 402 * get its length, then strip it off. 403 */ 404 len = sizeof(*reply); 405 if (m->m_len < len) { 406 m = m_pullup(m, len); 407 if (m == NULL) { 408 error = ENOBUFS; 409 goto out; 410 } 411 } 412 reply = mtod(m, struct krpc_reply *); 413 if (reply->rp_auth.authtype != 0) { 414 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 415 len = (len + 3) & ~3; /* XXX? */ 416 } 417 m_adj(m, len); 418 419 /* result */ 420 *data = m; 421 if (from_p) { 422 *from_p = from; 423 from = NULL; 424 } 425 426 out: 427 if (mhead) m_freem(mhead); 428 if (from) free(from, M_SONAME); 429 soclose(so); 430 return error; 431 } 432 433 /* 434 * eXternal Data Representation routines. 435 * (but with non-standard args...) 436 */ 437 438 /* 439 * String representation for RPC. 440 */ 441 struct xdr_string { 442 u_int32_t len; /* length without null or padding */ 443 char data[4]; /* data (longer, of course) */ 444 /* data is padded to a long-word boundary */ 445 }; 446 447 struct mbuf * 448 xdr_string_encode(char *str, int len) 449 { 450 struct mbuf *m; 451 struct xdr_string *xs; 452 int dlen; /* padded string length */ 453 int mlen; /* message length */ 454 455 dlen = (len + 3) & ~3; 456 mlen = dlen + 4; 457 458 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 459 return (NULL); 460 461 m = m_get2(mlen, M_WAITOK, MT_DATA, 0); 462 xs = mtod(m, struct xdr_string *); 463 m->m_len = mlen; 464 xs->len = txdr_unsigned(len); 465 bcopy(str, xs->data, len); 466 return (m); 467 } 468