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