1 /* $OpenBSD: pmap_rmt.c,v 1.36 2020/12/30 18:56:35 benno 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 DEF_WEAK(xdr_rmtcall_args); 128 129 /* 130 * XDR remote call results 131 * written for XDR_DECODE direction only 132 */ 133 bool_t 134 xdr_rmtcallres(XDR *xdrs, struct rmtcallres *crp) 135 { 136 caddr_t port_ptr; 137 138 port_ptr = (caddr_t)crp->port_ptr; 139 if (xdr_reference(xdrs, &port_ptr, sizeof (u_long), 140 xdr_u_long) && xdr_u_long(xdrs, &crp->resultslen)) { 141 crp->port_ptr = (u_long *)port_ptr; 142 return ((*(crp->xdr_results))(xdrs, crp->results_ptr)); 143 } 144 return (FALSE); 145 } 146 DEF_WEAK(xdr_rmtcallres); 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 == NULL || 167 ifa->ifa_addr->sa_family != AF_INET) 168 continue; 169 if ((ifa->ifa_flags & IFF_BROADCAST) && 170 (ifa->ifa_flags & IFF_UP) && 171 ifa->ifa_broadaddr && 172 ifa->ifa_broadaddr->sa_family == AF_INET) { 173 n++; 174 } 175 } 176 177 addrs = calloc(n, sizeof(*addrs)); 178 if (addrs == NULL) { 179 freeifaddrs(ifap); 180 return 0; 181 } 182 183 for (ifa = ifap; ifa; ifa = ifa->ifa_next) { 184 if (ifa->ifa_addr == NULL || 185 ifa->ifa_addr->sa_family != AF_INET) 186 continue; 187 if ((ifa->ifa_flags & IFF_BROADCAST) && 188 (ifa->ifa_flags & IFF_UP) && 189 ifa->ifa_broadaddr && 190 ifa->ifa_broadaddr->sa_family == AF_INET) { 191 sin = (struct sockaddr_in *)ifa->ifa_broadaddr; 192 addrs[i++] = sin->sin_addr; 193 } 194 } 195 196 freeifaddrs(ifap); 197 *addrsp = addrs; 198 return i; 199 } 200 201 typedef bool_t (*resultproc_t)(caddr_t, struct sockaddr_in *); 202 203 enum clnt_stat 204 clnt_broadcast(u_long prog, /* program number */ 205 u_long vers, /* version number */ 206 u_long proc, /* procedure number */ 207 xdrproc_t xargs, /* xdr routine for args */ 208 caddr_t argsp, /* pointer to args */ 209 xdrproc_t xresults, /* xdr routine for results */ 210 caddr_t resultsp, /* pointer to results */ 211 resultproc_t eachresult) /* call with each result obtained */ 212 { 213 enum clnt_stat stat; 214 AUTH *unix_auth; 215 XDR xdr_stream; 216 XDR *xdrs = &xdr_stream; 217 int outlen, inlen, nets; 218 socklen_t fromlen; 219 int sock = -1; 220 int on = 1; 221 struct pollfd pfd[1]; 222 int i; 223 int timo; 224 bool_t done = FALSE; 225 u_long xid; 226 u_long port; 227 struct in_addr *addrs = NULL; 228 struct sockaddr_in baddr, raddr; /* broadcast and response addresses */ 229 struct rmtcallargs a; 230 struct rmtcallres r; 231 struct rpc_msg msg; 232 char outbuf[MAX_BROADCAST_SIZE], inbuf[UDPMSGSIZE]; 233 234 if ((unix_auth = authunix_create_default()) == NULL) { 235 stat = RPC_AUTHERROR; 236 goto done_broad; 237 } 238 239 /* 240 * initialization: create a socket, a broadcast address, and 241 * preserialize the arguments into a send buffer. 242 */ 243 if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) { 244 stat = RPC_CANTSEND; 245 goto done_broad; 246 } 247 #ifdef SO_BROADCAST 248 if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) == -1) { 249 stat = RPC_CANTSEND; 250 goto done_broad; 251 } 252 #endif /* def SO_BROADCAST */ 253 254 pfd[0].fd = sock; 255 pfd[0].events = POLLIN; 256 257 nets = newgetbroadcastnets(&addrs); 258 if (nets == 0) { 259 stat = RPC_CANTSEND; 260 goto done_broad; 261 } 262 263 memset(&baddr, 0, sizeof (baddr)); 264 baddr.sin_len = sizeof(struct sockaddr_in); 265 baddr.sin_family = AF_INET; 266 baddr.sin_port = htons(PMAPPORT); 267 baddr.sin_addr.s_addr = htonl(INADDR_ANY); 268 msg.rm_xid = xid = arc4random(); 269 msg.rm_direction = CALL; 270 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; 271 msg.rm_call.cb_prog = PMAPPROG; 272 msg.rm_call.cb_vers = PMAPVERS; 273 msg.rm_call.cb_proc = PMAPPROC_CALLIT; 274 msg.rm_call.cb_cred = unix_auth->ah_cred; 275 msg.rm_call.cb_verf = unix_auth->ah_verf; 276 a.prog = prog; 277 a.vers = vers; 278 a.proc = proc; 279 a.xdr_args = xargs; 280 a.args_ptr = argsp; 281 r.port_ptr = &port; 282 r.xdr_results = xresults; 283 r.results_ptr = resultsp; 284 xdrmem_create(xdrs, outbuf, MAX_BROADCAST_SIZE, XDR_ENCODE); 285 if (!xdr_callmsg(xdrs, &msg) || !xdr_rmtcall_args(xdrs, &a)) { 286 stat = RPC_CANTENCODEARGS; 287 goto done_broad; 288 } 289 outlen = (int)xdr_getpos(xdrs); 290 xdr_destroy(xdrs); 291 292 /* 293 * Basic loop: broadcast a packet and wait a while for response(s). 294 * The response timeout grows larger per iteration. 295 * 296 * XXX This will loop about 5 times the stop. If there are 297 * lots of signals being received by the process it will quit 298 * send them all in one quick burst, not paying attention to 299 * the intended function of sending them slowly over half a 300 * minute or so 301 */ 302 for (timo = 4000; timo <= 14000; timo += 2000) { 303 for (i = 0; i < nets; i++) { 304 baddr.sin_addr = addrs[i]; 305 if (sendto(sock, outbuf, outlen, 0, 306 (struct sockaddr *)&baddr, 307 sizeof (struct sockaddr)) != outlen) { 308 stat = RPC_CANTSEND; 309 goto done_broad; 310 } 311 } 312 if (eachresult == NULL) { 313 stat = RPC_SUCCESS; 314 goto done_broad; 315 } 316 recv_again: 317 msg.acpted_rply.ar_verf = _null_auth; 318 msg.acpted_rply.ar_results.where = (caddr_t)&r; 319 msg.acpted_rply.ar_results.proc = xdr_rmtcallres; 320 321 switch (poll(pfd, 1, timo)) { 322 case 0: /* timed out */ 323 stat = RPC_TIMEDOUT; 324 continue; 325 case 1: 326 if (pfd[0].revents & POLLNVAL) 327 errno = EBADF; 328 else if (pfd[0].revents & POLLERR) 329 errno = EIO; 330 else 331 break; 332 /* FALLTHROUGH */ 333 case -1: /* some kind of error */ 334 if (errno == EINTR) 335 goto recv_again; 336 stat = RPC_CANTRECV; 337 goto done_broad; 338 } 339 try_again: 340 fromlen = sizeof(struct sockaddr); 341 inlen = recvfrom(sock, inbuf, UDPMSGSIZE, 0, 342 (struct sockaddr *)&raddr, &fromlen); 343 if (inlen == -1) { 344 if (errno == EINTR) 345 goto try_again; 346 stat = RPC_CANTRECV; 347 goto done_broad; 348 } 349 if (inlen < sizeof(u_int32_t)) 350 goto recv_again; 351 /* 352 * see if reply transaction id matches sent id. 353 * If so, decode the results. 354 */ 355 xdrmem_create(xdrs, inbuf, (u_int)inlen, XDR_DECODE); 356 if (xdr_replymsg(xdrs, &msg)) { 357 if ((msg.rm_xid == xid) && 358 (msg.rm_reply.rp_stat == MSG_ACCEPTED) && 359 (msg.acpted_rply.ar_stat == SUCCESS)) { 360 raddr.sin_port = htons((u_short)port); 361 done = (*eachresult)(resultsp, &raddr); 362 } 363 /* otherwise, we just ignore the errors ... */ 364 } 365 xdrs->x_op = XDR_FREE; 366 msg.acpted_rply.ar_results.proc = xdr_void; 367 (void)xdr_replymsg(xdrs, &msg); 368 (void)(*xresults)(xdrs, resultsp); 369 xdr_destroy(xdrs); 370 if (done) { 371 stat = RPC_SUCCESS; 372 goto done_broad; 373 } else { 374 goto recv_again; 375 } 376 } 377 done_broad: 378 free(addrs); 379 if (sock >= 0) 380 (void)close(sock); 381 if (unix_auth != NULL) 382 AUTH_DESTROY(unix_auth); 383 return (stat); 384 } 385