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: head/sys/nfs/krpc_subr.c 298788 2016-04-29 16:07:25Z pfg "); */ 47 __RCSID("$NetBSD: krpc_subr.c,v 1.6 2016/11/18 22:37:50 pgoyette Exp $"); 48 49 #include <sys/param.h> 50 #include <sys/systm.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 60 #include <netinet/in.h> 61 62 #include <fs/nfs/common/krpc.h> 63 #include <fs/nfs/common/xdr_subs.h> 64 65 /* 66 * Kernel support for Sun RPC 67 * 68 * Used currently for bootstrapping in nfs diskless configurations. 69 */ 70 71 /* 72 * Generic RPC headers 73 */ 74 75 struct auth_info { 76 u_int32_t authtype; /* auth type */ 77 u_int32_t authlen; /* auth length */ 78 }; 79 80 struct auth_unix { 81 int32_t ua_time; 82 int32_t ua_hostname; /* null */ 83 int32_t ua_uid; 84 int32_t ua_gid; 85 int32_t ua_gidlist; /* null */ 86 }; 87 88 struct krpc_call { 89 u_int32_t rp_xid; /* request transaction id */ 90 int32_t rp_direction; /* call direction (0) */ 91 u_int32_t rp_rpcvers; /* rpc version (2) */ 92 u_int32_t rp_prog; /* program */ 93 u_int32_t rp_vers; /* version */ 94 u_int32_t rp_proc; /* procedure */ 95 struct auth_info rpc_auth; 96 struct auth_unix rpc_unix; 97 struct auth_info rpc_verf; 98 }; 99 100 struct krpc_reply { 101 u_int32_t rp_xid; /* request transaction id */ 102 int32_t rp_direction; /* call direction (1) */ 103 int32_t rp_astatus; /* accept status (0: accepted) */ 104 union { 105 u_int32_t rpu_errno; 106 struct { 107 struct auth_info rok_auth; 108 u_int32_t rok_status; 109 } rpu_rok; 110 } rp_u; 111 }; 112 #define rp_errno rp_u.rpu_errno 113 #define rp_auth rp_u.rpu_rok.rok_auth 114 #define rp_status rp_u.rpu_rok.rok_status 115 116 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 117 118 /* 119 * What is the longest we will wait before re-sending a request? 120 * Note this is also the frequency of "RPC timeout" messages. 121 * The re-send loop count sup linearly to this maximum, so the 122 * first complaint will happen after (1+2+3+4+5)=15 seconds. 123 */ 124 #define MAX_RESEND_DELAY 5 /* seconds */ 125 126 /* 127 * Call portmap to lookup a port number for a particular rpc program 128 * Returns non-zero error on failure. 129 */ 130 int 131 krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp, 132 struct thread *td) 133 { 134 struct sdata { 135 u_int32_t prog; /* call program */ 136 u_int32_t vers; /* call version */ 137 u_int32_t proto; /* call protocol */ 138 u_int32_t port; /* call port (unused) */ 139 } *sdata; 140 struct rdata { 141 u_int16_t pad; 142 u_int16_t port; 143 } *rdata; 144 struct mbuf *m; 145 int error; 146 147 /* The portmapper port is fixed. */ 148 if (prog == PMAPPROG) { 149 *portp = htons(PMAPPORT); 150 return 0; 151 } 152 153 m = m_get(M_WAITOK, MT_DATA); 154 sdata = mtod(m, struct sdata *); 155 m->m_len = sizeof(*sdata); 156 157 /* Do the RPC to get it. */ 158 sdata->prog = txdr_unsigned(prog); 159 sdata->vers = txdr_unsigned(vers); 160 sdata->proto = txdr_unsigned(IPPROTO_UDP); 161 sdata->port = 0; 162 163 sin->sin_port = htons(PMAPPORT); 164 error = krpc_call(sin, PMAPPROG, PMAPVERS, 165 PMAPPROC_GETPORT, &m, NULL, td); 166 if (error) 167 goto out; 168 169 if (m->m_len < sizeof(*rdata)) { 170 m = m_pullup(m, sizeof(*rdata)); 171 if (m == NULL) 172 return ENOBUFS; 173 } 174 rdata = mtod(m, struct rdata *); 175 *portp = rdata->port; 176 177 out: 178 m_freem(m); 179 return error; 180 } 181 182 /* 183 * Do a remote procedure call (RPC) and wait for its reply. 184 * If from_p is non-null, then we are doing broadcast, and 185 * the address from whence the response came is saved there. 186 */ 187 int 188 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, 189 struct mbuf **data, struct sockaddr **from_p, struct thread *td) 190 { 191 struct socket *so; 192 struct sockaddr_in *sin, ssin; 193 struct sockaddr *from; 194 struct mbuf *m, *nam, *mhead; 195 struct krpc_call *call; 196 struct krpc_reply *reply; 197 struct sockopt sopt; 198 struct timeval tv; 199 struct uio auio; 200 int error, rcvflg, timo, secs, len; 201 static u_int32_t xid = ~0xFF; 202 u_int16_t tport; 203 u_int32_t saddr; 204 205 /* 206 * Validate address family. 207 * Sorry, this is INET specific... 208 */ 209 if (sa->sin_family != AF_INET) 210 return (EAFNOSUPPORT); 211 212 /* Free at end if not null. */ 213 nam = mhead = NULL; 214 from = NULL; 215 216 /* 217 * Create socket and set its receive timeout. 218 */ 219 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td->td_ucred, td))) 220 return error; 221 222 tv.tv_sec = 1; 223 tv.tv_usec = 0; 224 bzero(&sopt, sizeof sopt); 225 sopt.sopt_dir = SOPT_SET; 226 sopt.sopt_level = SOL_SOCKET; 227 sopt.sopt_name = SO_RCVTIMEO; 228 sopt.sopt_val = &tv; 229 sopt.sopt_valsize = sizeof tv; 230 231 if ((error = sosetopt(so, &sopt)) != 0) 232 goto out; 233 234 /* 235 * Enable broadcast if necessary. 236 */ 237 if (from_p) { 238 int on = 1; 239 sopt.sopt_name = SO_BROADCAST; 240 sopt.sopt_val = &on; 241 sopt.sopt_valsize = sizeof on; 242 if ((error = sosetopt(so, &sopt)) != 0) 243 goto out; 244 } 245 246 /* 247 * Bind the local endpoint to a reserved port, 248 * because some NFS servers refuse requests from 249 * non-reserved (non-privileged) ports. 250 */ 251 sin = &ssin; 252 bzero(sin, sizeof *sin); 253 sin->sin_len = sizeof(*sin); 254 sin->sin_family = AF_INET; 255 sin->sin_addr.s_addr = INADDR_ANY; 256 tport = IPPORT_RESERVED; 257 do { 258 tport--; 259 sin->sin_port = htons(tport); 260 error = sobind(so, (struct sockaddr *)sin, td); 261 } while (error == EADDRINUSE && 262 tport > IPPORT_RESERVED / 2); 263 if (error) { 264 printf("bind failed\n"); 265 goto out; 266 } 267 268 /* 269 * Setup socket address for the server. 270 */ 271 272 /* 273 * Prepend RPC message header. 274 */ 275 mhead = m_gethdr(M_WAITOK, MT_DATA); 276 mhead->m_next = *data; 277 *data = NULL; 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 m_reset_rcvif(mhead); 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