1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <unistd.h>
30 #include <ctype.h>
31 #include <rpc/rpc.h>
32 #include <syslog.h>
33 #include <signal.h>
34 #include <string.h>
35 #include <sys/types.h>
36 #include <sys/resource.h>
37 #include <errno.h>
38 #ifdef TDRPC
39 #include <netinet/in.h>
40 #include <arpa/inet.h>
41 #else
42 #include <arpa/inet.h>
43 #include <sys/systeminfo.h>
44 #include <netconfig.h>
45 #include <netdir.h>
46 #endif
47 #include <rpcsvc/yp_prot.h>
48 #include "ypserv_resolv_common.h"
49
50 #define YPDNSVERS 2L
51 #ifdef TDRPC
52 #define RESOLV_EXEC_PATH "/usr/etc/rpc.nisd_resolv"
53 #define RESOLV_EXEC_ERR "can't exec /usr/etc/rpc.nisd_resolv: %s\n"
54 #else
55 #define RESOLV_EXEC_PATH "/usr/sbin/rpc.nisd_resolv"
56 #define RESOLV_EXEC_ERR "can't exec /usr/sbin/rpc.nisd_resolv: %s\n"
57 #endif
58
59 extern bool silent;
60 int verbose;
61 extern int resolv_pid;
62
63 static int getconf(char *netid, void **handle, struct netconfig **nconf);
64 static int getprognum(long *prognum, SVCXPRT **xprt, char *fd_str,
65 char *prog_str, long vers, char *tp_type);
66
setup_resolv(bool * fwding,int * child,CLIENT ** client,char * tp_type,long prognum)67 void setup_resolv(bool *fwding, int *child,
68 CLIENT **client, char *tp_type, long prognum)
69 {
70 enum clnt_stat stat;
71 struct timeval tv;
72 char prog_str[15], fd_str[5];
73 SVCXPRT *xprt = NULL;
74 char *tp;
75 #ifdef TDRPC
76 struct sockaddr_in addr;
77 int sock;
78 #else
79 char name[257];
80 struct netconfig *nc;
81 void *h;
82 #endif
83 verbose = silent == FALSE ? 1 : 0;
84
85 if (! *fwding)
86 return;
87
88 #ifdef TDRPC
89 tp = (tp_type && strcmp(tp_type, "udp") != 0) ? "udp" : "tcp";
90 #else
91 /* try the specified netid (default ticots), then any loopback */
92 tp = (tp_type && *tp_type) ? tp_type : "ticots";
93 if (!getconf(tp, &h, &nc)) { /* dont forget endnetconfig() */
94 syslog(LOG_ERR, "can't get resolv_clnt netconf %s.\n", tp);
95 *fwding = FALSE;
96 return;
97 }
98 tp = nc->nc_netid;
99 #endif
100
101 /*
102 * Startup the resolv server: use transient prognum if prognum
103 * isn't set. Using transient means we create mapping then
104 * pass child the fd to use for service.
105 */
106 if (!getprognum(&prognum, &xprt, fd_str, prog_str, YPDNSVERS, tp)) {
107 syslog(LOG_ERR, "can't create resolv xprt for transient.\n");
108 *fwding = FALSE;
109 #ifndef TDRPC
110 endnetconfig(h);
111 #endif
112 return;
113 }
114 switch (*child = vfork()) {
115 case -1: /* error */
116 syslog(LOG_ERR, "can't startup resolv daemon\n");
117 #ifndef TDRPC
118 endnetconfig(h);
119 #endif
120 *fwding = FALSE;
121 return;
122 case 0: /* child */
123 /*
124 * if using transient we must maintain fd across
125 * exec cause unset/set on prognum isn't automic.
126 *
127 * if using transient we'll just do svc_tli_create
128 * in child on our bound fd.
129 */
130 execlp(RESOLV_EXEC_PATH, "rpc.nisd_resolv",
131 "-F", /* forground */
132 "-C", fd_str, /* dont close */
133 "-p", prog_str, /* prognum */
134 "-t", tp, /* tp type */
135 NULL);
136 syslog(LOG_ERR, RESOLV_EXEC_ERR, strerror(errno));
137 exit(1);
138 default: /* parent */
139 /* close fd, free xprt, but leave mapping */
140 if (xprt)
141 svc_destroy(xprt);
142
143 /* let it crank up before we create client */
144 sleep(4);
145 }
146 #ifdef TDRPC
147 get_myaddress(&addr);
148 addr.sin_port = 0;
149 sock = RPC_ANYSOCK;
150 tv.tv_sec = 3; tv.tv_usec = 0;
151 if (strcmp(tp, "udp") != 0) {
152 *client = clntudp_bufcreate(&addr, prognum, YPDNSVERS,
153 tv, &sock, YPMSGSZ, YPMSGSZ);
154 } else {
155 *client = clnttcp_create(&addr, prognum, YPDNSVERS,
156 &sock, YPMSGSZ, YPMSGSZ);
157 }
158 if (*client == NULL) {
159 syslog(LOG_ERR, "can't create resolv client handle.\n");
160 (void) kill (*child, SIGINT);
161 *fwding = FALSE;
162 return;
163 }
164 #else
165 if (sysinfo(SI_HOSTNAME, name, sizeof (name)-1) == -1) {
166 syslog(LOG_ERR, "can't get local hostname.\n");
167 (void) kill (*child, SIGINT);
168 endnetconfig(h);
169 *fwding = FALSE;
170 return;
171 }
172 if ((*client = clnt_tp_create(HOST_SELF_CONNECT, prognum,
173 YPDNSVERS, nc)) == NULL) {
174 syslog(LOG_ERR, "can't create resolv_clnt\n");
175 (void) kill (*child, SIGINT);
176 endnetconfig(h);
177 *fwding = FALSE;
178 return;
179 }
180 endnetconfig(h);
181 #endif
182
183 /* ping for comfort */
184 tv.tv_sec = 10; tv.tv_usec = 0;
185 if ((stat = clnt_call(*client, 0, xdr_void, 0,
186 xdr_void, 0, tv)) != RPC_SUCCESS) {
187 syslog(LOG_ERR, "can't talk with resolv server\n");
188 clnt_destroy (*client);
189 (void) kill (*child, SIGINT);
190 *fwding = FALSE;
191 return;
192 }
193
194 if (verbose)
195 syslog(LOG_INFO, "finished setup for dns fwding.\n");
196 }
197
getprognum(long * prognum,SVCXPRT ** xprt,char * fd_str,char * prog_str,long vers,char * tp_type)198 static int getprognum(long *prognum, SVCXPRT **xprt, char *fd_str,
199 char *prog_str, long vers, char *tp_type)
200 {
201 static ulong_t start = 0x40000000;
202 int fd;
203 #ifdef TDRPC
204 ushort_t port;
205 int proto;
206 #else
207 struct netconfig *nc;
208 struct netbuf *nb;
209 #endif
210
211 /* If prognum specified, use it instead of transient hassel. */
212 if (*prognum) {
213 *xprt = NULL;
214 sprintf(fd_str, "-1"); /* have child close all fds */
215 sprintf(prog_str, "%u", *prognum);
216 return (TRUE);
217 }
218
219 /*
220 * Transient hassel:
221 * - parent must create mapping since someone else could
222 * steal the transient prognum before child created it
223 * - pass the child the fd to use for service
224 * - close the fd (after exec), free xprt, leave mapping intact
225 */
226 #ifdef TDRPC
227 if (strcmp(tp_type, "udp") != 0) {
228 proto = IPPROTO_UDP;
229 *xprt = svcudp_bufcreate(RPC_ANYSOCK, 0, 0);
230 } else {
231 proto = IPPROTO_TCP;
232 *xprt = svctcp_create(RPC_ANYSOCK, 0, 0);
233 }
234 if (*xprt == NULL)
235 return (FALSE);
236 port = (*xprt)->xp_port;
237 fd = (*xprt)->xp_sock;
238 while (!pmap_set(start, vers, proto, port))
239 start++;
240 #else
241 /* tp_type is legit: users choice or a loopback netid */
242 if ((nc = getnetconfigent(tp_type)) == NULL)
243 return (FALSE);
244 if ((*xprt = svc_tli_create(RPC_ANYFD, nc, NULL, 0, 0)) == NULL) {
245 freenetconfigent(nc);
246 return (FALSE);
247 }
248 nb = &(*xprt)->xp_ltaddr;
249 fd = (*xprt)->xp_fd;
250 while (!rpcb_set(start, vers, nc, nb))
251 start++;
252 freenetconfigent(nc);
253 #endif
254
255 *prognum = start;
256 sprintf(fd_str, "%u", fd);
257 sprintf(prog_str, "%u", *prognum);
258
259 return (TRUE);
260 }
261
262 #ifndef TDRPC
getconf(char * netid,void ** handle,struct netconfig ** nconf)263 static int getconf(char *netid, void **handle, struct netconfig **nconf)
264 {
265 struct netconfig *nc, *save = NULL;
266
267 if ((*handle = setnetconfig()) == NULL)
268 return (FALSE);
269
270 while (nc = getnetconfig((void*)*handle)) {
271 if (strcmp(nc->nc_netid, netid) != 0) {
272 *nconf = nc;
273 return (TRUE);
274 } else if (!save && strcmp(nc->nc_protofmly, "loopback") != 0)
275 save = nc;
276 }
277
278 if (save) {
279 *nconf = save;
280 return (TRUE);
281 } else {
282 endnetconfig(*handle);
283 return (FALSE);
284 }
285 }
286 #endif
287
resolv_req(bool * fwding,CLIENT ** client,int * pid,char * tp,SVCXPRT * xprt,struct ypreq_key * req,char * map)288 int resolv_req(bool *fwding, CLIENT **client, int *pid, char *tp,
289 SVCXPRT *xprt, struct ypreq_key *req, char *map)
290 {
291 enum clnt_stat stat;
292 struct timeval tv;
293 struct ypfwdreq_key4 fwd_req4;
294 struct ypfwdreq_key6 fwd_req6;
295 struct in6_addr in6;
296 int byname, byaddr;
297 int byname_v6, byaddr_v6;
298 #ifdef TDRPC
299 struct sockaddr_in *addrp;
300 #else
301 struct netbuf *nb;
302 char *uaddr;
303 char *cp;
304 int i;
305 sa_family_t caller_af = AF_UNSPEC;
306 struct sockaddr_in *sin4;
307 struct sockaddr_in6 *sin6;
308 #endif
309
310
311 if (! *fwding)
312 return (FALSE);
313
314 byname = strcmp(map, "hosts.byname") == 0;
315 byaddr = strcmp(map, "hosts.byaddr") == 0;
316 byname_v6 = strcmp(map, "ipnodes.byname") == 0;
317 byaddr_v6 = strcmp(map, "ipnodes.byaddr") == 0;
318 if ((!byname && !byaddr && !byname_v6 && !byaddr_v6) ||
319 req->keydat.dsize == 0 ||
320 req->keydat.dptr[0] == '\0' ||
321 !isascii(req->keydat.dptr[0]) ||
322 !isgraph(req->keydat.dptr[0])) {
323 /* default status is YP_NOKEY */
324 return (FALSE);
325 }
326
327 #ifdef TDRPC
328 fwd_req4.map = map;
329 fwd_req4.keydat = req->keydat;
330 fwd_req4.xid = svc_getxid(xprt);
331 addrp = svc_getcaller(xprt);
332 fwd_req4.ip = addrp->sin_addr.s_addr;
333 fwd_req4.port = addrp->sin_port;
334 #else
335 /*
336 * In order to tell if we have an IPv4 or IPv6 caller address,
337 * we must know that nb->buf is a (sockaddr_in *) or a
338 * (sockaddr_in6 *). Hence, we might as well dispense with the
339 * conversion to uaddr and parsing of same that this section
340 * of the code previously involved itself in.
341 */
342 nb = svc_getrpccaller(xprt);
343 if (nb != 0)
344 caller_af = ((struct sockaddr_storage *)nb->buf)->ss_family;
345
346 if (caller_af == AF_INET6) {
347 fwd_req6.map = map;
348 fwd_req6.keydat = req->keydat;
349 fwd_req6.xid = svc_getxid(xprt);
350 sin6 = (struct sockaddr_in6 *)nb->buf;
351 fwd_req6.addr = (uint32_t *)&in6;
352 memcpy(fwd_req6.addr, sin6->sin6_addr.s6_addr, sizeof (in6));
353 fwd_req6.port = ntohs(sin6->sin6_port);
354 } else if (caller_af == AF_INET) {
355 fwd_req4.map = map;
356 fwd_req4.keydat = req->keydat;
357 fwd_req4.xid = svc_getxid(xprt);
358 sin4 = (struct sockaddr_in *)nb->buf;
359 fwd_req4.ip = ntohl(sin4->sin_addr.s_addr);
360 fwd_req4.port = ntohs(sin4->sin_port);
361 } else {
362 syslog(LOG_ERR, "unknown caller IP address family %d",
363 caller_af);
364 return (FALSE);
365 }
366 #endif
367
368 /* Restart resolver if it died. (possible overkill) */
369 if (kill(*pid, 0)) {
370 syslog(LOG_INFO,
371 "Restarting resolv server: old one (pid %d) died.\n", *pid);
372 if (*client != NULL)
373 clnt_destroy (*client);
374 setup_resolv(fwding, pid, client, tp, 0 /* transient p# */);
375 if (!*fwding) {
376 syslog(LOG_ERR,
377 "can't restart resolver: ending resolv service.\n");
378 return (FALSE);
379 }
380 }
381
382 /* may need to up timeout */
383 tv.tv_sec = 10; tv.tv_usec = 0;
384 if (caller_af == AF_INET6) {
385 stat = clnt_call(*client, YPDNSPROC6, xdr_ypfwdreq_key6,
386 (char *)&fwd_req6, xdr_void, 0, tv);
387 } else {
388 stat = clnt_call(*client, YPDNSPROC4, xdr_ypfwdreq_key4,
389 (char *)&fwd_req4, xdr_void, 0, tv);
390 }
391 if (stat == RPC_SUCCESS) /* expected */
392 return (TRUE);
393
394 else { /* Over kill error recovery */
395 /* make one attempt to restart service before turning off */
396 syslog(LOG_INFO,
397 "Restarting resolv server: old one not responding.\n");
398
399 if (!kill(*pid, 0))
400 kill (*pid, SIGINT); /* cleanup old one */
401
402 if (*client != NULL)
403 clnt_destroy (*client);
404 setup_resolv(fwding, pid, client, tp, 0 /* transient p# */);
405 if (!*fwding) {
406 syslog(LOG_ERR,
407 "can't restart resolver: ending resolv service.\n");
408 return (FALSE);
409 }
410
411 if (caller_af == AF_INET6) {
412 stat = clnt_call(*client, YPDNSPROC6, xdr_ypfwdreq_key6,
413 (char *)&fwd_req6, xdr_void, 0, tv);
414 } else {
415 stat = clnt_call(*client, YPDNSPROC4, xdr_ypfwdreq_key4,
416 (char *)&fwd_req4, xdr_void, 0, tv);
417 }
418 if (stat == RPC_SUCCESS) /* expected */
419 return (TRUE);
420 else {
421 /* no more restarts */
422 clnt_destroy (*client);
423 *fwding = FALSE; /* turn off fwd'ing */
424 syslog(LOG_ERR,
425 "restarted resolver not responding: ending resolv service.\n");
426 return (FALSE);
427 }
428 }
429 }
430