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/param.h> 47 #include <sys/systm.h> 48 #include <sys/jail.h> 49 #include <sys/malloc.h> 50 #include <sys/mbuf.h> 51 #include <sys/proc.h> 52 #include <sys/socket.h> 53 #include <sys/socketvar.h> 54 #include <sys/uio.h> 55 56 #include <net/if.h> 57 #include <net/vnet.h> 58 59 #include <netinet/in.h> 60 61 #include <rpc/types.h> 62 #include <rpc/auth.h> 63 #include <rpc/rpc_msg.h> 64 #include <nfs/krpc.h> 65 #include <nfs/xdr_subs.h> 66 67 /* 68 * Kernel support for Sun RPC 69 * 70 * Used currently for bootstrapping in nfs diskless configurations. 71 */ 72 73 /* 74 * Generic RPC headers 75 */ 76 77 struct auth_info { 78 u_int32_t authtype; /* auth type */ 79 u_int32_t authlen; /* auth length */ 80 }; 81 82 struct auth_unix { 83 int32_t ua_time; 84 int32_t ua_hostname; /* null */ 85 int32_t ua_uid; 86 int32_t ua_gid; 87 int32_t ua_gidlist; /* null */ 88 }; 89 90 struct krpc_call { 91 u_int32_t rp_xid; /* request transaction id */ 92 int32_t rp_direction; /* call direction (0) */ 93 u_int32_t rp_rpcvers; /* rpc version (2) */ 94 u_int32_t rp_prog; /* program */ 95 u_int32_t rp_vers; /* version */ 96 u_int32_t rp_proc; /* procedure */ 97 struct auth_info rpc_auth; 98 struct auth_unix rpc_unix; 99 struct auth_info rpc_verf; 100 }; 101 102 struct krpc_reply { 103 u_int32_t rp_xid; /* request transaction id */ 104 int32_t rp_direction; /* call direction (1) */ 105 int32_t rp_astatus; /* accept status (0: accepted) */ 106 union { 107 u_int32_t rpu_errno; 108 struct { 109 struct auth_info rok_auth; 110 u_int32_t rok_status; 111 } rpu_rok; 112 } rp_u; 113 }; 114 #define rp_errno rp_u.rpu_errno 115 #define rp_auth rp_u.rpu_rok.rok_auth 116 #define rp_status rp_u.rpu_rok.rok_status 117 118 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 119 120 /* 121 * What is the longest we will wait before re-sending a request? 122 * Note this is also the frequency of "RPC timeout" messages. 123 * The re-send loop count sup linearly to this maximum, so the 124 * first complaint will happen after (1+2+3+4+5)=15 seconds. 125 */ 126 #define MAX_RESEND_DELAY 5 /* seconds */ 127 128 /* 129 * Call portmap to lookup a port number for a particular rpc program 130 * Returns non-zero error on failure. 131 */ 132 int 133 krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp, 134 struct thread *td) 135 { 136 struct sdata { 137 u_int32_t prog; /* call program */ 138 u_int32_t vers; /* call version */ 139 u_int32_t proto; /* call protocol */ 140 u_int32_t port; /* call port (unused) */ 141 } *sdata; 142 struct rdata { 143 u_int16_t pad; 144 u_int16_t port; 145 } *rdata; 146 struct mbuf *m; 147 int error; 148 149 /* The portmapper port is fixed. */ 150 if (prog == PMAPPROG) { 151 *portp = htons(PMAPPORT); 152 return 0; 153 } 154 155 m = m_get(M_WAITOK, MT_DATA); 156 sdata = mtod(m, struct sdata *); 157 m->m_len = sizeof(*sdata); 158 159 /* Do the RPC to get it. */ 160 sdata->prog = txdr_unsigned(prog); 161 sdata->vers = txdr_unsigned(vers); 162 sdata->proto = txdr_unsigned(IPPROTO_UDP); 163 sdata->port = 0; 164 165 sin->sin_port = htons(PMAPPORT); 166 error = krpc_call(sin, PMAPPROG, PMAPVERS, 167 PMAPPROC_GETPORT, &m, NULL, td); 168 if (error) 169 return error; 170 171 if (m->m_len < sizeof(*rdata)) { 172 m = m_pullup(m, sizeof(*rdata)); 173 if (m == NULL) 174 return ENOBUFS; 175 } 176 rdata = mtod(m, struct rdata *); 177 *portp = rdata->port; 178 179 m_freem(m); 180 return 0; 181 } 182 183 /* 184 * Do a remote procedure call (RPC) and wait for its reply. 185 * If from_p is non-null, then we are doing broadcast, and 186 * the address from whence the response came is saved there. 187 */ 188 int 189 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 190 struct mbuf **data, struct sockaddr **from_p, struct thread *td) 191 { 192 struct socket *so; 193 struct sockaddr_in *sin, ssin; 194 struct sockaddr *from; 195 struct mbuf *m, *mhead; 196 struct krpc_call *call; 197 struct krpc_reply *reply; 198 struct sockopt sopt; 199 struct timeval tv; 200 struct uio auio; 201 int error, rcvflg, timo, secs, len; 202 static u_int32_t xid = ~0xFF; 203 u_int16_t tport; 204 u_int32_t saddr; 205 206 /* 207 * Validate address family. 208 * Sorry, this is INET specific... 209 */ 210 if (sa->sin_family != AF_INET) 211 return (EAFNOSUPPORT); 212 213 /* Free at end if not null. */ 214 mhead = NULL; 215 from = NULL; 216 217 /* 218 * Create socket and set its receive timeout. 219 */ 220 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td->td_ucred, td))) 221 return error; 222 223 tv.tv_sec = 1; 224 tv.tv_usec = 0; 225 bzero(&sopt, sizeof sopt); 226 sopt.sopt_dir = SOPT_SET; 227 sopt.sopt_level = SOL_SOCKET; 228 sopt.sopt_name = SO_RCVTIMEO; 229 sopt.sopt_val = &tv; 230 sopt.sopt_valsize = sizeof tv; 231 232 if ((error = sosetopt(so, &sopt)) != 0) 233 goto out; 234 235 /* 236 * Enable broadcast if necessary. 237 */ 238 if (from_p) { 239 int on = 1; 240 sopt.sopt_name = SO_BROADCAST; 241 sopt.sopt_val = &on; 242 sopt.sopt_valsize = sizeof on; 243 if ((error = sosetopt(so, &sopt)) != 0) 244 goto out; 245 } 246 247 /* 248 * Bind the local endpoint to a reserved port, 249 * because some NFS servers refuse requests from 250 * non-reserved (non-privileged) ports. 251 */ 252 sin = &ssin; 253 bzero(sin, sizeof *sin); 254 sin->sin_len = sizeof(*sin); 255 sin->sin_family = AF_INET; 256 sin->sin_addr.s_addr = INADDR_ANY; 257 tport = IPPORT_RESERVED; 258 do { 259 tport--; 260 sin->sin_port = htons(tport); 261 error = sobind(so, (struct sockaddr *)sin, td); 262 } while (error == EADDRINUSE && 263 tport > IPPORT_RESERVED / 2); 264 if (error) { 265 printf("bind failed\n"); 266 goto out; 267 } 268 269 /* 270 * Setup socket address for the server. 271 */ 272 273 /* 274 * Prepend RPC message header. 275 */ 276 mhead = m_gethdr(M_WAITOK, MT_DATA); 277 mhead->m_next = *data; 278 call = mtod(mhead, struct krpc_call *); 279 mhead->m_len = sizeof(*call); 280 bzero((caddr_t)call, sizeof(*call)); 281 /* rpc_call part */ 282 xid++; 283 call->rp_xid = txdr_unsigned(xid); 284 /* call->rp_direction = 0; */ 285 call->rp_rpcvers = txdr_unsigned(2); 286 call->rp_prog = txdr_unsigned(prog); 287 call->rp_vers = txdr_unsigned(vers); 288 call->rp_proc = txdr_unsigned(func); 289 /* rpc_auth part (auth_unix as root) */ 290 call->rpc_auth.authtype = txdr_unsigned(AUTH_UNIX); 291 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix)); 292 /* rpc_verf part (auth_null) */ 293 call->rpc_verf.authtype = 0; 294 call->rpc_verf.authlen = 0; 295 296 /* 297 * Setup packet header 298 */ 299 m_fixhdr(mhead); 300 mhead->m_pkthdr.rcvif = NULL; 301 302 /* 303 * Send it, repeatedly, until a reply is received, 304 * but delay each re-send by an increasing amount. 305 * If the delay hits the maximum, start complaining. 306 */ 307 timo = 0; 308 for (;;) { 309 /* Send RPC request (or re-send). */ 310 m = m_copym(mhead, 0, M_COPYALL, M_WAITOK); 311 error = sosend(so, (struct sockaddr *)sa, NULL, m, 312 NULL, 0, td); 313 if (error) { 314 printf("krpc_call: sosend: %d\n", error); 315 goto out; 316 } 317 m = NULL; 318 319 /* Determine new timeout. */ 320 if (timo < MAX_RESEND_DELAY) 321 timo++; 322 else { 323 saddr = ntohl(sa->sin_addr.s_addr); 324 printf("RPC timeout for server %d.%d.%d.%d\n", 325 (saddr >> 24) & 255, 326 (saddr >> 16) & 255, 327 (saddr >> 8) & 255, 328 saddr & 255); 329 } 330 331 /* 332 * Wait for up to timo seconds for a reply. 333 * The socket receive timeout was set to 1 second. 334 */ 335 secs = timo; 336 while (secs > 0) { 337 if (from) { 338 free(from, M_SONAME); 339 from = NULL; 340 } 341 if (m) { 342 m_freem(m); 343 m = NULL; 344 } 345 bzero(&auio, sizeof(auio)); 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 krpc_reply *); 363 364 /* Is it the right reply? */ 365 if (reply->rp_direction != txdr_unsigned(REPLY)) 366 continue; 367 368 if (reply->rp_xid != txdr_unsigned(xid)) 369 continue; 370 371 /* Was RPC accepted? (authorization OK) */ 372 if (reply->rp_astatus != 0) { 373 error = fxdr_unsigned(u_int32_t, reply->rp_errno); 374 printf("rpc denied, error=%d\n", error); 375 continue; 376 } 377 378 /* Did the call succeed? */ 379 if (reply->rp_status != 0) { 380 error = fxdr_unsigned(u_int32_t, reply->rp_status); 381 if (error == PROG_MISMATCH) { 382 error = EBADRPC; 383 goto out; 384 } 385 printf("rpc denied, status=%d\n", error); 386 continue; 387 } 388 389 goto gotreply; /* break two levels */ 390 391 } /* while secs */ 392 } /* forever send/receive */ 393 394 error = ETIMEDOUT; 395 goto out; 396 397 gotreply: 398 399 /* 400 * Get RPC reply header into first mbuf, 401 * get its length, then strip it off. 402 */ 403 len = sizeof(*reply); 404 if (m->m_len < len) { 405 m = m_pullup(m, len); 406 if (m == NULL) { 407 error = ENOBUFS; 408 goto out; 409 } 410 } 411 reply = mtod(m, struct krpc_reply *); 412 if (reply->rp_auth.authtype != 0) { 413 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); 414 len = (len + 3) & ~3; /* XXX? */ 415 } 416 m_adj(m, len); 417 418 /* result */ 419 *data = m; 420 if (from_p) { 421 *from_p = from; 422 from = NULL; 423 } 424 425 out: 426 if (mhead) m_freem(mhead); 427 if (from) free(from, M_SONAME); 428 soclose(so); 429 return error; 430 } 431 432 /* 433 * eXternal Data Representation routines. 434 * (but with non-standard args...) 435 */ 436 437 /* 438 * String representation for RPC. 439 */ 440 struct xdr_string { 441 u_int32_t len; /* length without null or padding */ 442 char data[4]; /* data (longer, of course) */ 443 /* data is padded to a long-word boundary */ 444 }; 445 446 struct mbuf * 447 xdr_string_encode(char *str, int len) 448 { 449 struct mbuf *m; 450 struct xdr_string *xs; 451 int dlen; /* padded string length */ 452 int mlen; /* message length */ 453 454 dlen = (len + 3) & ~3; 455 mlen = dlen + 4; 456 457 if (mlen > MCLBYTES) /* If too big, we just can't do it. */ 458 return (NULL); 459 460 m = m_get2(mlen, M_WAITOK, MT_DATA, 0); 461 xs = mtod(m, struct xdr_string *); 462 m->m_len = mlen; 463 xs->len = txdr_unsigned(len); 464 bcopy(str, xs->data, len); 465 return (m); 466 } 467