1 /* $NetBSD: krpc_subr.c,v 1.7 1994/09/26 16:42:31 gwr Exp $ */ 2 3 /* 4 * Copyright (c) 1994 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/param.h> 46 #include <sys/conf.h> 47 #include <sys/ioctl.h> 48 #include <sys/proc.h> 49 #include <sys/mount.h> 50 #include <sys/mbuf.h> 51 #include <sys/socket.h> 52 #include <sys/systm.h> 53 #include <sys/reboot.h> 54 55 #include <net/if.h> 56 #include <netinet/in.h> 57 58 #include <nfs/rpcv2.h> 59 #include <nfs/krpc.h> 60 61 /* 62 * Kernel support for Sun RPC 63 * 64 * Used currently for bootstrapping in nfs diskless configurations. 65 * 66 * Note: will not work on variable-sized rpc args/results. 67 * implicit size-limit of an mbuf. 68 */ 69 70 /* 71 * Generic RPC headers 72 */ 73 74 struct auth_info { 75 int rp_atype; /* auth type */ 76 u_long rp_alen; /* auth length */ 77 }; 78 79 struct rpc_call { 80 u_long rp_xid; /* request transaction id */ 81 int rp_direction; /* call direction (0) */ 82 u_long rp_rpcvers; /* rpc version (2) */ 83 u_long rp_prog; /* program */ 84 u_long rp_vers; /* version */ 85 u_long rp_proc; /* procedure */ 86 struct auth_info rp_auth; 87 struct auth_info rp_verf; 88 }; 89 90 struct rpc_reply { 91 u_long rp_xid; /* request transaction id */ 92 int rp_direction; /* call direction (1) */ 93 int rp_astatus; /* accept status (0: accepted) */ 94 union { 95 u_long rpu_errno; 96 struct { 97 struct auth_info rp_auth; 98 u_long rp_rstatus; /* reply status */ 99 } rpu_ok; 100 } rp_u; 101 }; 102 103 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ 104 105 /* 106 * What is the longest we will wait before re-sending a request? 107 * Note this is also the frequency of "RPC timeout" messages. 108 * The re-send loop count sup linearly to this maximum, so the 109 * first complaint will happen after (1+2+3+4+5)=15 seconds. 110 */ 111 #define MAX_RESEND_DELAY 5 /* seconds */ 112 113 /* 114 * Call portmap to lookup a port number for a particular rpc program 115 * Returns non-zero error on failure. 116 */ 117 int 118 krpc_portmap(sin, prog, vers, portp) 119 struct sockaddr_in *sin; /* server address */ 120 u_long prog, vers; /* host order */ 121 u_short *portp; /* network order */ 122 { 123 struct sdata { 124 u_long prog; /* call program */ 125 u_long vers; /* call version */ 126 u_long proto; /* call protocol */ 127 u_long port; /* call port (unused) */ 128 } *sdata; 129 struct rdata { 130 u_short pad; 131 u_short port; 132 } *rdata; 133 struct mbuf *m; 134 int error; 135 136 /* The portmapper port is fixed. */ 137 if (prog == PMAPPROG) { 138 *portp = htons(PMAPPORT); 139 return 0; 140 } 141 142 m = m_gethdr(M_WAIT, MT_DATA); 143 if (m == NULL) 144 return ENOBUFS; 145 m->m_len = sizeof(*sdata); 146 m->m_pkthdr.len = m->m_len; 147 sdata = mtod(m, struct sdata *); 148 149 /* Do the RPC to get it. */ 150 sdata->prog = htonl(prog); 151 sdata->vers = htonl(vers); 152 sdata->proto = htonl(IPPROTO_UDP); 153 sdata->port = 0; 154 155 sin->sin_port = htons(PMAPPORT); 156 error = krpc_call(sin, PMAPPROG, PMAPVERS, 157 PMAPPROC_GETPORT, &m, NULL); 158 if (error) 159 return error; 160 161 rdata = mtod(m, struct rdata *); 162 *portp = rdata->port; 163 164 m_freem(m); 165 return 0; 166 } 167 168 /* 169 * Do a remote procedure call (RPC) and wait for its reply. 170 * If from_p is non-null, then we are doing broadcast, and 171 * the address from whence the response came is saved there. 172 */ 173 int 174 krpc_call(sa, prog, vers, func, data, from_p) 175 struct sockaddr_in *sa; 176 u_long prog, vers, func; 177 struct mbuf **data; /* input/output */ 178 struct mbuf **from_p; /* output */ 179 { 180 struct socket *so; 181 struct sockaddr_in *sin; 182 struct mbuf *m, *nam, *mhead, *from; 183 struct rpc_call *call; 184 struct rpc_reply *reply; 185 struct uio auio; 186 int error, rcvflg, timo, secs, len; 187 static u_long xid = ~0xFF; 188 u_short tport; 189 190 /* 191 * Validate address family. 192 * Sorry, this is INET specific... 193 */ 194 if (sa->sin_family != AF_INET) 195 return (EAFNOSUPPORT); 196 197 /* Free at end if not null. */ 198 nam = mhead = NULL; 199 from = NULL; 200 201 /* 202 * Create socket and set its recieve timeout. 203 */ 204 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0))) 205 goto out; 206 207 m = m_get(M_WAIT, MT_SOOPTS); 208 if (m == NULL) { 209 error = ENOBUFS; 210 goto out; 211 } else { 212 struct timeval *tv; 213 tv = mtod(m, struct timeval *); 214 m->m_len = sizeof(*tv); 215 tv->tv_sec = 1; 216 tv->tv_usec = 0; 217 if ((error = sosetopt(so, SOL_SOCKET, SO_RCVTIMEO, m))) 218 goto out; 219 } 220 221 /* 222 * Enable broadcast if necessary. 223 */ 224 if (from_p) { 225 int *on; 226 m = m_get(M_WAIT, MT_SOOPTS); 227 if (m == NULL) { 228 error = ENOBUFS; 229 goto out; 230 } 231 on = mtod(m, int *); 232 m->m_len = sizeof(*on); 233 *on = 1; 234 if ((error = sosetopt(so, SOL_SOCKET, SO_BROADCAST, m))) 235 goto out; 236 } 237 238 /* 239 * Bind the local endpoint to a reserved port, 240 * because some NFS servers refuse requests from 241 * non-reserved (non-privileged) ports. 242 */ 243 m = m_getclr(M_WAIT, MT_SONAME); 244 sin = mtod(m, struct sockaddr_in *); 245 sin->sin_len = m->m_len = sizeof(*sin); 246 sin->sin_family = AF_INET; 247 sin->sin_addr.s_addr = INADDR_ANY; 248 tport = IPPORT_RESERVED; 249 do { 250 tport--; 251 sin->sin_port = htons(tport); 252 error = sobind(so, m); 253 } while (error == EADDRINUSE && 254 tport > IPPORT_RESERVED / 2); 255 m_freem(m); 256 if (error) { 257 printf("bind failed\n"); 258 goto out; 259 } 260 261 /* 262 * Setup socket address for the server. 263 */ 264 nam = m_get(M_WAIT, MT_SONAME); 265 if (nam == NULL) { 266 error = ENOBUFS; 267 goto out; 268 } 269 sin = mtod(nam, struct sockaddr_in *); 270 bcopy((caddr_t)sa, (caddr_t)sin, (nam->m_len = sa->sin_len)); 271 272 /* 273 * Prepend RPC message header. 274 */ 275 m = *data; 276 *data = NULL; 277 #ifdef DIAGNOSTIC 278 if ((m->m_flags & M_PKTHDR) == 0) 279 panic("krpc_call: send data w/o pkthdr"); 280 if (m->m_pkthdr.len < m->m_len) 281 panic("krpc_call: pkthdr.len not set"); 282 #endif 283 mhead = m_prepend(m, sizeof(*call), M_WAIT); 284 if (mhead == NULL) { 285 error = ENOBUFS; 286 goto out; 287 } 288 mhead->m_pkthdr.len += sizeof(*call); 289 mhead->m_pkthdr.rcvif = NULL; 290 291 /* 292 * Fill in the RPC header 293 */ 294 call = mtod(mhead, struct rpc_call *); 295 bzero((caddr_t)call, sizeof(*call)); 296 xid++; 297 call->rp_xid = htonl(xid); 298 /* call->rp_direction = 0; */ 299 call->rp_rpcvers = htonl(2); 300 call->rp_prog = htonl(prog); 301 call->rp_vers = htonl(vers); 302 call->rp_proc = htonl(func); 303 /* call->rp_auth = 0; */ 304 /* call->rp_verf = 0; */ 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_WAIT); 315 if (m == NULL) { 316 error = ENOBUFS; 317 goto out; 318 } 319 error = sosend(so, nam, NULL, m, NULL, 0); 320 if (error) { 321 printf("krpc_call: sosend: %d\n", error); 322 goto out; 323 } 324 m = NULL; 325 326 /* Determine new timeout. */ 327 if (timo < MAX_RESEND_DELAY) 328 timo++; 329 else 330 printf("RPC timeout for server 0x%x\n", 331 ntohl(sin->sin_addr.s_addr)); 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 m_freem(from); 341 from = NULL; 342 } 343 if (m) { 344 m_freem(m); 345 m = NULL; 346 } 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 rpc_reply *); 364 365 /* Is it the right reply? */ 366 if (reply->rp_direction != htonl(RPC_REPLY)) 367 continue; 368 369 if (reply->rp_xid != htonl(xid)) 370 continue; 371 372 /* Was RPC accepted? (authorization OK) */ 373 if (reply->rp_astatus != 0) { 374 error = ntohl(reply->rp_u.rpu_errno); 375 printf("rpc denied, error=%d\n", error); 376 continue; 377 } 378 379 /* Did the call succeed? */ 380 if ((error = ntohl(reply->rp_u.rpu_ok.rp_rstatus)) != 0) { 381 printf("rpc status=%d\n", error); 382 continue; 383 } 384 385 goto gotreply; /* break two levels */ 386 387 } /* while secs */ 388 } /* forever send/receive */ 389 390 error = ETIMEDOUT; 391 goto out; 392 393 gotreply: 394 395 /* 396 * Pull as much as we can into first mbuf, to make 397 * result buffer contiguous. Note that if the entire 398 * result won't fit into one mbuf, you're out of luck. 399 * XXX - Should not rely on making the entire reply 400 * contiguous (fix callers instead). -gwr 401 */ 402 #ifdef DIAGNOSTIC 403 if ((m->m_flags & M_PKTHDR) == 0) 404 panic("krpc_call: received pkt w/o header?"); 405 #endif 406 len = m->m_pkthdr.len; 407 if (m->m_len < len) { 408 m = m_pullup(m, len); 409 if (m == NULL) { 410 error = ENOBUFS; 411 goto out; 412 } 413 reply = mtod(m, struct rpc_reply *); 414 } 415 416 /* 417 * Strip RPC header 418 */ 419 len = sizeof(*reply); 420 if (reply->rp_u.rpu_ok.rp_auth.rp_atype != 0) { 421 len += ntohl(reply->rp_u.rpu_ok.rp_auth.rp_alen); 422 len = (len + 3) & ~3; /* XXX? */ 423 } 424 m_adj(m, len); 425 426 /* result */ 427 *data = m; 428 if (from_p) { 429 *from_p = from; 430 from = NULL; 431 } 432 433 out: 434 if (nam) m_freem(nam); 435 if (mhead) m_freem(mhead); 436 if (from) m_freem(from); 437 soclose(so); 438 return error; 439 } 440