xref: /netbsd-src/external/bsd/am-utils/dist/amd/amq_svc.c (revision 274254cdae52594c1aa480a736aef78313d15c9c)
1 /*	$NetBSD: amq_svc.c,v 1.1.1.2 2009/03/20 20:26:49 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997-2009 Erez Zadok
5  * Copyright (c) 1990 Jan-Simon Pendry
6  * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
7  * Copyright (c) 1990 The Regents of the University of California.
8  * All rights reserved.
9  *
10  * This code is derived from software contributed to Berkeley by
11  * Jan-Simon Pendry at Imperial College, London.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgment:
23  *      This product includes software developed by the University of
24  *      California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *
42  * File: am-utils/amd/amq_svc.c
43  *
44  */
45 
46 #ifdef HAVE_CONFIG_H
47 # include <config.h>
48 #endif /* HAVE_CONFIG_H */
49 #include <am_defs.h>
50 #include <amd.h>
51 
52 /* typedefs */
53 typedef char *(*amqsvcproc_t)(voidp, struct svc_req *);
54 
55 #if defined(HAVE_TCPD_H) && defined(HAVE_LIBWRAP)
56 # ifdef NEED_LIBWRAP_SEVERITY_VARIABLES
57 /*
58  * Some systems that define libwrap already define these two variables
59  * in libwrap, while others don't: so I need to know precisely iff
60  * to define these two severity variables.
61  */
62 int allow_severity=0, deny_severity=0, rfc931_timeout=0;
63 # endif /* NEED_LIBWRAP_SEVERITY_VARIABLES */
64 
65 /*
66  * check if remote amq is authorized to access this amd.
67  * Returns: 1=allowed, 0=denied.
68  */
69 static int
70 amqsvc_is_client_allowed(const struct sockaddr_in *addr, char *remote)
71 {
72   struct hostent *h;
73   char *name = NULL, **ad;
74   int ret = 0;			/* default is 0==denied */
75 
76   /* Check IP address */
77   if (hosts_ctl(AMD_SERVICE_NAME, "", remote, "")) {
78     ret = 1;
79     goto out;
80   }
81   /* Get address */
82   if (!(h = gethostbyaddr((const char *)&(addr->sin_addr),
83                           sizeof(addr->sin_addr),
84                           AF_INET)))
85     goto out;
86   if (!(name = strdup(h->h_name)))
87     goto out;
88   /* Paranoia check */
89   if (!(h = gethostbyname(name)))
90     goto out;
91   for (ad = h->h_addr_list; *ad; ad++)
92     if (!memcmp(*ad, &(addr->sin_addr), h->h_length))
93       break;
94   if (!*ad)
95     goto out;
96   if (hosts_ctl(AMD_SERVICE_NAME, "", h->h_name, "")) {
97     return 1;
98     goto out;
99   }
100   /* Check aliases */
101   for (ad = h->h_aliases; *ad; ad++)
102     if (hosts_ctl(AMD_SERVICE_NAME, "", *ad, "")) {
103       return 1;
104       goto out;
105     }
106 
107  out:
108   if (name)
109     XFREE(name);
110   return ret;
111 }
112 #endif /* defined(HAVE_TCPD_H) && defined(HAVE_LIBWRAP) */
113 
114 
115 /*
116  * Prepare the parent and child:
117  * 1) Setup IPC pipe.
118  * 2) Set signal masks.
119  * 3) Fork by calling background() so that NumChildren is updated.
120  */
121 static int
122 amq_fork(opaque_t argp)
123 {
124 #ifdef HAVE_SIGACTION
125   sigset_t new, mask;
126 #else /* not HAVE_SIGACTION */
127   int mask;
128 #endif /* not HAVE_SIGACTION */
129   am_node *mp;
130   pid_t pid;
131 
132   mp = find_ap(*(char **) argp);
133   if (mp == NULL) {
134     errno = 0;
135     return -1;
136   }
137 
138   if (pipe(mp->am_fd) == -1) {
139     mp->am_fd[0] = -1;
140     mp->am_fd[1] = -1;
141     return -1;
142   }
143 
144 #ifdef HAVE_SIGACTION
145   sigemptyset(&new);		/* initialize signal set we wish to block */
146   sigaddset(&new, SIGHUP);
147   sigaddset(&new, SIGINT);
148   sigaddset(&new, SIGQUIT);
149   sigaddset(&new, SIGCHLD);
150   sigprocmask(SIG_BLOCK, &new, &mask);
151 #else /* not HAVE_SIGACTION */
152   mask =
153       sigmask(SIGHUP) |
154       sigmask(SIGINT) |
155       sigmask(SIGQUIT) |
156       sigmask(SIGCHLD);
157   mask = sigblock(mask);
158 #endif /* not HAVE_SIGACTION */
159 
160   switch ((pid = background())) {
161   case -1:	/* error */
162     dlog("amq_fork failed");
163     return -1;
164 
165   case 0:	/* child */
166     close(mp->am_fd[1]);	/* close output end of pipe */
167     mp->am_fd[1] = -1;
168     return 0;
169 
170   default:	/* parent */
171     close(mp->am_fd[0]);	/* close input end of pipe */
172     mp->am_fd[0] = -1;
173 
174 #ifdef HAVE_SIGACTION
175     sigprocmask(SIG_SETMASK, &mask, NULL);
176 #else /* not HAVE_SIGACTION */
177     sigsetmask(mask);
178 #endif /* not HAVE_SIGACTION */
179     return pid;
180   }
181 }
182 
183 
184 void
185 amq_program_1(struct svc_req *rqstp, SVCXPRT *transp)
186 {
187   union {
188     amq_string amqproc_mnttree_1_arg;
189     amq_string amqproc_umnt_1_arg;
190     amq_setopt amqproc_setopt_1_arg;
191   } argument;
192   char *result;
193   xdrproc_t xdr_argument, xdr_result;
194   amqsvcproc_t local;
195   amqsvcproc_t child;
196   amqsvcproc_t parent;
197   pid_t pid;
198 
199 #if defined(HAVE_TCPD_H) && defined(HAVE_LIBWRAP)
200   if (gopt.flags & CFM_USE_TCPWRAPPERS) {
201     struct sockaddr_in *remote_addr = svc_getcaller(rqstp->rq_xprt);
202     char *remote_hostname = inet_ntoa(remote_addr->sin_addr);
203 
204     if (!amqsvc_is_client_allowed(remote_addr, remote_hostname)) {
205       plog(XLOG_WARNING, "Amd denied remote amq service to %s", remote_hostname);
206       svcerr_auth(transp, AUTH_FAILED);
207       return;
208     } else {
209       dlog("Amd allowed remote amq service to %s", remote_hostname);
210     }
211   }
212 #endif /* defined(HAVE_TCPD_H) && defined(HAVE_LIBWRAP) */
213 
214   local = NULL;
215   child = NULL;
216   parent = NULL;
217 
218   switch (rqstp->rq_proc) {
219 
220   case AMQPROC_NULL:
221     xdr_argument = (xdrproc_t) xdr_void;
222     xdr_result = (xdrproc_t) xdr_void;
223     local = (amqsvcproc_t) amqproc_null_1_svc;
224     break;
225 
226   case AMQPROC_MNTTREE:
227     xdr_argument = (xdrproc_t) xdr_amq_string;
228     xdr_result = (xdrproc_t) xdr_amq_mount_tree_p;
229     local = (amqsvcproc_t) amqproc_mnttree_1_svc;
230     break;
231 
232   case AMQPROC_UMNT:
233     xdr_argument = (xdrproc_t) xdr_amq_string;
234     xdr_result = (xdrproc_t) xdr_void;
235     local = (amqsvcproc_t) amqproc_umnt_1_svc;
236     break;
237 
238   case AMQPROC_STATS:
239     xdr_argument = (xdrproc_t) xdr_void;
240     xdr_result = (xdrproc_t) xdr_amq_mount_stats;
241     local = (amqsvcproc_t) amqproc_stats_1_svc;
242     break;
243 
244   case AMQPROC_EXPORT:
245     xdr_argument = (xdrproc_t) xdr_void;
246     xdr_result = (xdrproc_t) xdr_amq_mount_tree_list;
247     local = (amqsvcproc_t) amqproc_export_1_svc;
248     break;
249 
250   case AMQPROC_SETOPT:
251     xdr_argument = (xdrproc_t) xdr_amq_setopt;
252     xdr_result = (xdrproc_t) xdr_int;
253     local = (amqsvcproc_t) amqproc_setopt_1_svc;
254     break;
255 
256   case AMQPROC_GETMNTFS:
257     xdr_argument = (xdrproc_t) xdr_void;
258     xdr_result = (xdrproc_t) xdr_amq_mount_info_qelem;
259     local = (amqsvcproc_t) amqproc_getmntfs_1_svc;
260     break;
261 
262   case AMQPROC_GETVERS:
263     xdr_argument = (xdrproc_t) xdr_void;
264     xdr_result = (xdrproc_t) xdr_amq_string;
265     local = (amqsvcproc_t) amqproc_getvers_1_svc;
266     break;
267 
268   case AMQPROC_GETPID:
269     xdr_argument = (xdrproc_t) xdr_void;
270     xdr_result = (xdrproc_t) xdr_int;
271     local = (amqsvcproc_t) amqproc_getpid_1_svc;
272     break;
273 
274   case AMQPROC_PAWD:
275     xdr_argument = (xdrproc_t) xdr_amq_string;
276     xdr_result = (xdrproc_t) xdr_amq_string;
277     local = (amqsvcproc_t) amqproc_pawd_1_svc;
278     break;
279 
280   case AMQPROC_SYNC_UMNT:
281     xdr_argument = (xdrproc_t) xdr_amq_string;
282     xdr_result = (xdrproc_t) xdr_amq_sync_umnt;
283     parent = (amqsvcproc_t) amqproc_sync_umnt_1_svc_parent;
284     child = (amqsvcproc_t) amqproc_sync_umnt_1_svc_child;
285     /* used if fork fails */
286     local = (amqsvcproc_t) amqproc_sync_umnt_1_svc_async;
287     break;
288 
289   default:
290     svcerr_noproc(transp);
291     return;
292   }
293 
294   memset((char *) &argument, 0, sizeof(argument));
295   if (!svc_getargs(transp,
296 		   (XDRPROC_T_TYPE) xdr_argument,
297 		   (SVC_IN_ARG_TYPE) & argument)) {
298     svcerr_decode(transp);
299     return;
300   }
301 
302   pid = -1;
303   result = NULL;
304 
305   if (child) {
306     switch ((pid = amq_fork(&argument))) {
307     case -1:	/* error */
308       break;
309 
310     case 0:	/* child */
311       result = (*child) (&argument, rqstp);
312       local = NULL;
313       break;
314 
315     default:	/* parent */
316       result = (*parent) (&argument, rqstp);
317       local = NULL;
318       break;
319     }
320   }
321 
322   if (local)
323     result = (*local) (&argument, rqstp);
324 
325   if (result != NULL && !svc_sendreply(transp,
326 				       (XDRPROC_T_TYPE) xdr_result,
327 				       result)) {
328     svcerr_systemerr(transp);
329   }
330 
331   if (!svc_freeargs(transp,
332 		    (XDRPROC_T_TYPE) xdr_argument,
333 		    (SVC_IN_ARG_TYPE) & argument)) {
334     plog(XLOG_FATAL, "unable to free rpc arguments in amqprog_1");
335     going_down(1);
336   }
337 
338   if (pid == 0)
339     exit(0);	/* the child is done! */
340 }
341