1 /* $OpenBSD: pmap_rmt.c,v 1.29 2010/09/01 14:43:34 millert 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 if (sock != -1) 95 (void)close(sock); 96 addr->sin_port = 0; 97 return (stat); 98 } 99 100 101 /* 102 * XDR remote call arguments 103 * written for XDR_ENCODE direction only 104 */ 105 bool_t 106 xdr_rmtcall_args(XDR *xdrs, struct rmtcallargs *cap) 107 { 108 u_int lenposition, argposition, position; 109 110 if (xdr_u_long(xdrs, &(cap->prog)) && 111 xdr_u_long(xdrs, &(cap->vers)) && 112 xdr_u_long(xdrs, &(cap->proc))) { 113 lenposition = XDR_GETPOS(xdrs); 114 if (! xdr_u_long(xdrs, &(cap->arglen))) 115 return (FALSE); 116 argposition = XDR_GETPOS(xdrs); 117 if (! (*(cap->xdr_args))(xdrs, cap->args_ptr)) 118 return (FALSE); 119 position = XDR_GETPOS(xdrs); 120 cap->arglen = (u_long)position - (u_long)argposition; 121 XDR_SETPOS(xdrs, lenposition); 122 if (! xdr_u_long(xdrs, &(cap->arglen))) 123 return (FALSE); 124 XDR_SETPOS(xdrs, position); 125 return (TRUE); 126 } 127 return (FALSE); 128 } 129 130 /* 131 * XDR remote call results 132 * written for XDR_DECODE direction only 133 */ 134 bool_t 135 xdr_rmtcallres(XDR *xdrs, struct rmtcallres *crp) 136 { 137 caddr_t port_ptr; 138 139 port_ptr = (caddr_t)crp->port_ptr; 140 if (xdr_reference(xdrs, &port_ptr, sizeof (u_long), 141 xdr_u_long) && xdr_u_long(xdrs, &crp->resultslen)) { 142 crp->port_ptr = (u_long *)port_ptr; 143 return ((*(crp->xdr_results))(xdrs, crp->results_ptr)); 144 } 145 return (FALSE); 146 } 147 148 149 /* 150 * The following is kludged-up support for simple rpc broadcasts. 151 * Someday a large, complicated system will replace these trivial 152 * routines which only support udp/ip . 153 */ 154 static int 155 newgetbroadcastnets(struct in_addr **addrsp) 156 { 157 struct ifaddrs *ifap, *ifa; 158 struct sockaddr_in *sin; 159 struct in_addr *addrs; 160 int i = 0, n = 0; 161 162 if (getifaddrs(&ifap) != 0) 163 return 0; 164 165 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 166 if (ifa->ifa_addr->sa_family != AF_INET) 167 continue; 168 if ((ifa->ifa_flags & IFF_BROADCAST) && 169 (ifa->ifa_flags & IFF_UP) && 170 ifa->ifa_broadaddr && 171 ifa->ifa_broadaddr->sa_family == AF_INET) { 172 n++; 173 } 174 } 175 176 addrs = (struct in_addr *)calloc(n, sizeof(*addrs)); 177 if (addrs == NULL) { 178 freeifaddrs(ifap); 179 return 0; 180 } 181 182 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 183 if (ifa->ifa_addr->sa_family != AF_INET) 184 continue; 185 if ((ifa->ifa_flags & IFF_BROADCAST) && 186 (ifa->ifa_flags & IFF_UP) && 187 ifa->ifa_broadaddr && 188 ifa->ifa_broadaddr->sa_family == AF_INET) { 189 sin = (struct sockaddr_in *)ifa->ifa_broadaddr; 190 addrs[i++] = sin->sin_addr; 191 } 192 } 193 194 freeifaddrs(ifap); 195 *addrsp = addrs; 196 return i; 197 } 198 199 typedef bool_t (*resultproc_t)(); 200 201 enum clnt_stat 202 clnt_broadcast(u_long prog, /* program number */ 203 u_long vers, /* version number */ 204 u_long proc, /* procedure number */ 205 xdrproc_t xargs, /* xdr routine for args */ 206 caddr_t argsp, /* pointer to args */ 207 xdrproc_t xresults, /* xdr routine for results */ 208 caddr_t resultsp, /* pointer to results */ 209 resultproc_t eachresult) /* call with each result obtained */ 210 { 211 enum clnt_stat stat; 212 AUTH *unix_auth; 213 XDR xdr_stream; 214 XDR *xdrs = &xdr_stream; 215 int outlen, inlen, nets; 216 socklen_t fromlen; 217 int sock = -1; 218 int on = 1; 219 struct pollfd pfd[1]; 220 int i; 221 int timo; 222 bool_t done = FALSE; 223 u_long xid; 224 u_long port; 225 struct in_addr *addrs = NULL; 226 struct sockaddr_in baddr, raddr; /* broadcast and response addresses */ 227 struct rmtcallargs a; 228 struct rmtcallres r; 229 struct rpc_msg msg; 230 char outbuf[MAX_BROADCAST_SIZE], inbuf[UDPMSGSIZE]; 231 232 if ((unix_auth = authunix_create_default()) == NULL) { 233 stat = RPC_AUTHERROR; 234 goto done_broad; 235 } 236 237 /* 238 * initialization: create a socket, a broadcast address, and 239 * preserialize the arguments into a send buffer. 240 */ 241 if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) { 242 stat = RPC_CANTSEND; 243 goto done_broad; 244 } 245 #ifdef SO_BROADCAST 246 if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) < 0) { 247 stat = RPC_CANTSEND; 248 goto done_broad; 249 } 250 #endif /* def SO_BROADCAST */ 251 252 pfd[0].fd = sock; 253 pfd[0].events = POLLIN; 254 255 nets = newgetbroadcastnets(&addrs); 256 if (nets == 0) { 257 stat = RPC_CANTSEND; 258 goto done_broad; 259 } 260 261 memset(&baddr, 0, sizeof (baddr)); 262 baddr.sin_len = sizeof(struct sockaddr_in); 263 baddr.sin_family = AF_INET; 264 baddr.sin_port = htons(PMAPPORT); 265 baddr.sin_addr.s_addr = htonl(INADDR_ANY); 266 msg.rm_xid = xid = arc4random(); 267 msg.rm_direction = CALL; 268 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 269 msg.rm_call.cb_prog = PMAPPROG; 270 msg.rm_call.cb_vers = PMAPVERS; 271 msg.rm_call.cb_proc = PMAPPROC_CALLIT; 272 msg.rm_call.cb_cred = unix_auth->ah_cred; 273 msg.rm_call.cb_verf = unix_auth->ah_verf; 274 a.prog = prog; 275 a.vers = vers; 276 a.proc = proc; 277 a.xdr_args = xargs; 278 a.args_ptr = argsp; 279 r.port_ptr = &port; 280 r.xdr_results = xresults; 281 r.results_ptr = resultsp; 282 xdrmem_create(xdrs, outbuf, MAX_BROADCAST_SIZE, XDR_ENCODE); 283 if (!xdr_callmsg(xdrs, &msg) || !xdr_rmtcall_args(xdrs, &a)) { 284 stat = RPC_CANTENCODEARGS; 285 goto done_broad; 286 } 287 outlen = (int)xdr_getpos(xdrs); 288 xdr_destroy(xdrs); 289 290 /* 291 * Basic loop: broadcast a packet and wait a while for response(s). 292 * The response timeout grows larger per iteration. 293 * 294 * XXX This will loop about 5 times the stop. If there are 295 * lots of signals being received by the process it will quit 296 * send them all in one quick burst, not paying attention to 297 * the intended function of sending them slowly over half a 298 * minute or so 299 */ 300 for (timo = 4000; timo <= 14000; timo += 2000) { 301 for (i = 0; i < nets; i++) { 302 baddr.sin_addr = addrs[i]; 303 if (sendto(sock, outbuf, outlen, 0, 304 (struct sockaddr *)&baddr, 305 sizeof (struct sockaddr)) != outlen) { 306 stat = RPC_CANTSEND; 307 goto done_broad; 308 } 309 } 310 if (eachresult == NULL) { 311 stat = RPC_SUCCESS; 312 goto done_broad; 313 } 314 recv_again: 315 msg.acpted_rply.ar_verf = _null_auth; 316 msg.acpted_rply.ar_results.where = (caddr_t)&r; 317 msg.acpted_rply.ar_results.proc = xdr_rmtcallres; 318 319 switch (poll(pfd, 1, timo)) { 320 case 0: /* timed out */ 321 stat = RPC_TIMEDOUT; 322 continue; 323 case 1: 324 if (pfd[0].revents & POLLNVAL) 325 errno = EBADF; 326 else if (pfd[0].revents & POLLERR) 327 errno = EIO; 328 else 329 break; 330 /* FALLTHROUGH */ 331 case -1: /* some kind of error */ 332 if (errno == EINTR) 333 goto recv_again; 334 stat = RPC_CANTRECV; 335 goto done_broad; 336 } 337 try_again: 338 fromlen = sizeof(struct sockaddr); 339 inlen = recvfrom(sock, inbuf, UDPMSGSIZE, 0, 340 (struct sockaddr *)&raddr, &fromlen); 341 if (inlen < 0) { 342 if (errno == EINTR) 343 goto try_again; 344 stat = RPC_CANTRECV; 345 goto done_broad; 346 } 347 if (inlen < sizeof(u_int32_t)) 348 goto recv_again; 349 /* 350 * see if reply transaction id matches sent id. 351 * If so, decode the results. 352 */ 353 xdrmem_create(xdrs, inbuf, (u_int)inlen, XDR_DECODE); 354 if (xdr_replymsg(xdrs, &msg)) { 355 if ((msg.rm_xid == xid) && 356 (msg.rm_reply.rp_stat == MSG_ACCEPTED) && 357 (msg.acpted_rply.ar_stat == SUCCESS)) { 358 raddr.sin_port = htons((u_short)port); 359 done = (*eachresult)(resultsp, &raddr); 360 } 361 /* otherwise, we just ignore the errors ... */ 362 } 363 xdrs->x_op = XDR_FREE; 364 msg.acpted_rply.ar_results.proc = xdr_void; 365 (void)xdr_replymsg(xdrs, &msg); 366 (void)(*xresults)(xdrs, resultsp); 367 xdr_destroy(xdrs); 368 if (done) { 369 stat = RPC_SUCCESS; 370 goto done_broad; 371 } else { 372 goto recv_again; 373 } 374 } 375 done_broad: 376 if (addrs) 377 free(addrs); 378 if (sock >= 0) 379 (void)close(sock); 380 if (unix_auth != NULL) 381 AUTH_DESTROY(unix_auth); 382 return (stat); 383 } 384