1 /* $OpenBSD: pmap_rmt.c,v 1.31 2014/11/11 04:51:49 guenther Exp $ */ 2 3 /* 4 * Copyright (c) 2010, Oracle America, Inc. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are 8 * met: 9 * 10 * * Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * * Redistributions in binary form must reproduce the above 13 * copyright notice, this list of conditions and the following 14 * disclaimer in the documentation and/or other materials 15 * provided with the distribution. 16 * * Neither the name of the "Oracle America, Inc." nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 25 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 /* 35 * pmap_rmt.c 36 * Client interface to pmap rpc service. 37 * remote call and broadcast service 38 */ 39 40 #include <rpc/rpc.h> 41 #include <rpc/pmap_prot.h> 42 #include <rpc/pmap_clnt.h> 43 #include <rpc/pmap_rmt.h> 44 #include <sys/socket.h> 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <unistd.h> 48 #include <errno.h> 49 #include <string.h> 50 #include <net/if.h> 51 #include <sys/ioctl.h> 52 #include <arpa/inet.h> 53 #include <ifaddrs.h> 54 #define MAX_BROADCAST_SIZE 1400 55 56 static struct timeval timeout = { 3, 0 }; 57 58 59 /* 60 * pmapper remote-call-service interface. 61 * This routine is used to call the pmapper remote call service 62 * which will look up a service program in the port maps, and then 63 * remotely call that routine with the given parameters. This allows 64 * programs to do a lookup and call in one step. 65 */ 66 enum clnt_stat 67 pmap_rmtcall(struct sockaddr_in *addr, u_long prog, u_long vers, u_long proc, 68 xdrproc_t xdrargs, caddr_t argsp, xdrproc_t xdrres, caddr_t resp, 69 struct timeval tout, u_long *port_ptr) 70 { 71 int sock = -1; 72 CLIENT *client; 73 struct rmtcallargs a; 74 struct rmtcallres r; 75 enum clnt_stat stat; 76 77 addr->sin_port = htons(PMAPPORT); 78 client = clntudp_create(addr, PMAPPROG, PMAPVERS, timeout, &sock); 79 if (client != NULL) { 80 a.prog = prog; 81 a.vers = vers; 82 a.proc = proc; 83 a.args_ptr = argsp; 84 a.xdr_args = xdrargs; 85 r.port_ptr = port_ptr; 86 r.results_ptr = resp; 87 r.xdr_results = xdrres; 88 stat = CLNT_CALL(client, PMAPPROC_CALLIT, xdr_rmtcall_args, &a, 89 xdr_rmtcallres, &r, tout); 90 CLNT_DESTROY(client); 91 } else { 92 stat = RPC_FAILED; 93 } 94 addr->sin_port = 0; 95 return (stat); 96 } 97 98 99 /* 100 * XDR remote call arguments 101 * written for XDR_ENCODE direction only 102 */ 103 bool_t 104 xdr_rmtcall_args(XDR *xdrs, struct rmtcallargs *cap) 105 { 106 u_int lenposition, argposition, position; 107 108 if (xdr_u_long(xdrs, &(cap->prog)) && 109 xdr_u_long(xdrs, &(cap->vers)) && 110 xdr_u_long(xdrs, &(cap->proc))) { 111 lenposition = XDR_GETPOS(xdrs); 112 if (! xdr_u_long(xdrs, &(cap->arglen))) 113 return (FALSE); 114 argposition = XDR_GETPOS(xdrs); 115 if (! (*(cap->xdr_args))(xdrs, cap->args_ptr)) 116 return (FALSE); 117 position = XDR_GETPOS(xdrs); 118 cap->arglen = (u_long)position - (u_long)argposition; 119 XDR_SETPOS(xdrs, lenposition); 120 if (! xdr_u_long(xdrs, &(cap->arglen))) 121 return (FALSE); 122 XDR_SETPOS(xdrs, position); 123 return (TRUE); 124 } 125 return (FALSE); 126 } 127 128 /* 129 * XDR remote call results 130 * written for XDR_DECODE direction only 131 */ 132 bool_t 133 xdr_rmtcallres(XDR *xdrs, struct rmtcallres *crp) 134 { 135 caddr_t port_ptr; 136 137 port_ptr = (caddr_t)crp->port_ptr; 138 if (xdr_reference(xdrs, &port_ptr, sizeof (u_long), 139 xdr_u_long) && xdr_u_long(xdrs, &crp->resultslen)) { 140 crp->port_ptr = (u_long *)port_ptr; 141 return ((*(crp->xdr_results))(xdrs, crp->results_ptr)); 142 } 143 return (FALSE); 144 } 145 146 147 /* 148 * The following is kludged-up support for simple rpc broadcasts. 149 * Someday a large, complicated system will replace these trivial 150 * routines which only support udp/ip . 151 */ 152 static int 153 newgetbroadcastnets(struct in_addr **addrsp) 154 { 155 struct ifaddrs *ifap, *ifa; 156 struct sockaddr_in *sin; 157 struct in_addr *addrs; 158 int i = 0, n = 0; 159 160 if (getifaddrs(&ifap) != 0) 161 return 0; 162 163 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 164 if (ifa->ifa_addr->sa_family != AF_INET) 165 continue; 166 if ((ifa->ifa_flags & IFF_BROADCAST) && 167 (ifa->ifa_flags & IFF_UP) && 168 ifa->ifa_broadaddr && 169 ifa->ifa_broadaddr->sa_family == AF_INET) { 170 n++; 171 } 172 } 173 174 addrs = (struct in_addr *)calloc(n, sizeof(*addrs)); 175 if (addrs == NULL) { 176 freeifaddrs(ifap); 177 return 0; 178 } 179 180 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 181 if (ifa->ifa_addr->sa_family != AF_INET) 182 continue; 183 if ((ifa->ifa_flags & IFF_BROADCAST) && 184 (ifa->ifa_flags & IFF_UP) && 185 ifa->ifa_broadaddr && 186 ifa->ifa_broadaddr->sa_family == AF_INET) { 187 sin = (struct sockaddr_in *)ifa->ifa_broadaddr; 188 addrs[i++] = sin->sin_addr; 189 } 190 } 191 192 freeifaddrs(ifap); 193 *addrsp = addrs; 194 return i; 195 } 196 197 typedef bool_t (*resultproc_t)(caddr_t, struct sockaddr_in *); 198 199 enum clnt_stat 200 clnt_broadcast(u_long prog, /* program number */ 201 u_long vers, /* version number */ 202 u_long proc, /* procedure number */ 203 xdrproc_t xargs, /* xdr routine for args */ 204 caddr_t argsp, /* pointer to args */ 205 xdrproc_t xresults, /* xdr routine for results */ 206 caddr_t resultsp, /* pointer to results */ 207 resultproc_t eachresult) /* call with each result obtained */ 208 { 209 enum clnt_stat stat; 210 AUTH *unix_auth; 211 XDR xdr_stream; 212 XDR *xdrs = &xdr_stream; 213 int outlen, inlen, nets; 214 socklen_t fromlen; 215 int sock = -1; 216 int on = 1; 217 struct pollfd pfd[1]; 218 int i; 219 int timo; 220 bool_t done = FALSE; 221 u_long xid; 222 u_long port; 223 struct in_addr *addrs = NULL; 224 struct sockaddr_in baddr, raddr; /* broadcast and response addresses */ 225 struct rmtcallargs a; 226 struct rmtcallres r; 227 struct rpc_msg msg; 228 char outbuf[MAX_BROADCAST_SIZE], inbuf[UDPMSGSIZE]; 229 230 if ((unix_auth = authunix_create_default()) == NULL) { 231 stat = RPC_AUTHERROR; 232 goto done_broad; 233 } 234 235 /* 236 * initialization: create a socket, a broadcast address, and 237 * preserialize the arguments into a send buffer. 238 */ 239 if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) { 240 stat = RPC_CANTSEND; 241 goto done_broad; 242 } 243 #ifdef SO_BROADCAST 244 if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) < 0) { 245 stat = RPC_CANTSEND; 246 goto done_broad; 247 } 248 #endif /* def SO_BROADCAST */ 249 250 pfd[0].fd = sock; 251 pfd[0].events = POLLIN; 252 253 nets = newgetbroadcastnets(&addrs); 254 if (nets == 0) { 255 stat = RPC_CANTSEND; 256 goto done_broad; 257 } 258 259 memset(&baddr, 0, sizeof (baddr)); 260 baddr.sin_len = sizeof(struct sockaddr_in); 261 baddr.sin_family = AF_INET; 262 baddr.sin_port = htons(PMAPPORT); 263 baddr.sin_addr.s_addr = htonl(INADDR_ANY); 264 msg.rm_xid = xid = arc4random(); 265 msg.rm_direction = CALL; 266 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 267 msg.rm_call.cb_prog = PMAPPROG; 268 msg.rm_call.cb_vers = PMAPVERS; 269 msg.rm_call.cb_proc = PMAPPROC_CALLIT; 270 msg.rm_call.cb_cred = unix_auth->ah_cred; 271 msg.rm_call.cb_verf = unix_auth->ah_verf; 272 a.prog = prog; 273 a.vers = vers; 274 a.proc = proc; 275 a.xdr_args = xargs; 276 a.args_ptr = argsp; 277 r.port_ptr = &port; 278 r.xdr_results = xresults; 279 r.results_ptr = resultsp; 280 xdrmem_create(xdrs, outbuf, MAX_BROADCAST_SIZE, XDR_ENCODE); 281 if (!xdr_callmsg(xdrs, &msg) || !xdr_rmtcall_args(xdrs, &a)) { 282 stat = RPC_CANTENCODEARGS; 283 goto done_broad; 284 } 285 outlen = (int)xdr_getpos(xdrs); 286 xdr_destroy(xdrs); 287 288 /* 289 * Basic loop: broadcast a packet and wait a while for response(s). 290 * The response timeout grows larger per iteration. 291 * 292 * XXX This will loop about 5 times the stop. If there are 293 * lots of signals being received by the process it will quit 294 * send them all in one quick burst, not paying attention to 295 * the intended function of sending them slowly over half a 296 * minute or so 297 */ 298 for (timo = 4000; timo <= 14000; timo += 2000) { 299 for (i = 0; i < nets; i++) { 300 baddr.sin_addr = addrs[i]; 301 if (sendto(sock, outbuf, outlen, 0, 302 (struct sockaddr *)&baddr, 303 sizeof (struct sockaddr)) != outlen) { 304 stat = RPC_CANTSEND; 305 goto done_broad; 306 } 307 } 308 if (eachresult == NULL) { 309 stat = RPC_SUCCESS; 310 goto done_broad; 311 } 312 recv_again: 313 msg.acpted_rply.ar_verf = _null_auth; 314 msg.acpted_rply.ar_results.where = (caddr_t)&r; 315 msg.acpted_rply.ar_results.proc = xdr_rmtcallres; 316 317 switch (poll(pfd, 1, timo)) { 318 case 0: /* timed out */ 319 stat = RPC_TIMEDOUT; 320 continue; 321 case 1: 322 if (pfd[0].revents & POLLNVAL) 323 errno = EBADF; 324 else if (pfd[0].revents & POLLERR) 325 errno = EIO; 326 else 327 break; 328 /* FALLTHROUGH */ 329 case -1: /* some kind of error */ 330 if (errno == EINTR) 331 goto recv_again; 332 stat = RPC_CANTRECV; 333 goto done_broad; 334 } 335 try_again: 336 fromlen = sizeof(struct sockaddr); 337 inlen = recvfrom(sock, inbuf, UDPMSGSIZE, 0, 338 (struct sockaddr *)&raddr, &fromlen); 339 if (inlen < 0) { 340 if (errno == EINTR) 341 goto try_again; 342 stat = RPC_CANTRECV; 343 goto done_broad; 344 } 345 if (inlen < sizeof(u_int32_t)) 346 goto recv_again; 347 /* 348 * see if reply transaction id matches sent id. 349 * If so, decode the results. 350 */ 351 xdrmem_create(xdrs, inbuf, (u_int)inlen, XDR_DECODE); 352 if (xdr_replymsg(xdrs, &msg)) { 353 if ((msg.rm_xid == xid) && 354 (msg.rm_reply.rp_stat == MSG_ACCEPTED) && 355 (msg.acpted_rply.ar_stat == SUCCESS)) { 356 raddr.sin_port = htons((u_short)port); 357 done = (*eachresult)(resultsp, &raddr); 358 } 359 /* otherwise, we just ignore the errors ... */ 360 } 361 xdrs->x_op = XDR_FREE; 362 msg.acpted_rply.ar_results.proc = xdr_void; 363 (void)xdr_replymsg(xdrs, &msg); 364 (void)(*xresults)(xdrs, resultsp); 365 xdr_destroy(xdrs); 366 if (done) { 367 stat = RPC_SUCCESS; 368 goto done_broad; 369 } else { 370 goto recv_again; 371 } 372 } 373 done_broad: 374 if (addrs) 375 free(addrs); 376 if (sock >= 0) 377 (void)close(sock); 378 if (unix_auth != NULL) 379 AUTH_DESTROY(unix_auth); 380 return (stat); 381 } 382