xref: /freebsd/sys/nfs/nfs_nfssvc.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*-
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Rick Macklem at The University of Guelph.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_nfs.h"
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/sysproto.h>
42 #include <sys/kernel.h>
43 #include <sys/sysctl.h>
44 #include <sys/priv.h>
45 #include <sys/proc.h>
46 #include <sys/lock.h>
47 #include <sys/mutex.h>
48 #include <sys/module.h>
49 #include <sys/sysent.h>
50 #include <sys/syscall.h>
51 #include <sys/sysproto.h>
52 
53 #include <security/audit/audit.h>
54 
55 #include <nfs/nfssvc.h>
56 
57 static int nfssvc_offset = SYS_nfssvc;
58 static struct sysent nfssvc_prev_sysent;
59 MAKE_SYSENT(nfssvc);
60 
61 /*
62  * This tiny module simply handles the nfssvc() system call. The other
63  * nfs modules that use the system call register themselves by setting
64  * the nfsd_call_xxx function pointers non-NULL.
65  */
66 
67 int (*nfsd_call_nfsserver)(struct thread *, struct nfssvc_args *) = NULL;
68 int (*nfsd_call_nfscommon)(struct thread *, struct nfssvc_args *) = NULL;
69 int (*nfsd_call_nfscl)(struct thread *, struct nfssvc_args *) = NULL;
70 int (*nfsd_call_nfsd)(struct thread *, struct nfssvc_args *) = NULL;
71 
72 /*
73  * Nfs server psuedo system call for the nfsd's
74  */
75 int
76 nfssvc(struct thread *td, struct nfssvc_args *uap)
77 {
78 	int error;
79 
80 	KASSERT(!mtx_owned(&Giant), ("nfssvc(): called with Giant"));
81 
82 	AUDIT_ARG_CMD(uap->flag);
83 
84 	/* Allow anyone to get the stats. */
85 	if ((uap->flag & ~NFSSVC_GETSTATS) != 0) {
86 		error = priv_check(td, PRIV_NFS_DAEMON);
87 		if (error != 0)
88 			return (error);
89 	}
90 	error = EINVAL;
91 	if ((uap->flag & (NFSSVC_ADDSOCK | NFSSVC_OLDNFSD | NFSSVC_NFSD)) &&
92 	    nfsd_call_nfsserver != NULL)
93 		error = (*nfsd_call_nfsserver)(td, uap);
94 	else if ((uap->flag & (NFSSVC_CBADDSOCK | NFSSVC_NFSCBD)) &&
95 	    nfsd_call_nfscl != NULL)
96 		error = (*nfsd_call_nfscl)(td, uap);
97 	else if ((uap->flag & (NFSSVC_IDNAME | NFSSVC_GETSTATS |
98 	    NFSSVC_GSSDADDPORT | NFSSVC_GSSDADDFIRST | NFSSVC_GSSDDELETEALL |
99 	    NFSSVC_NFSUSERDPORT | NFSSVC_NFSUSERDDELPORT)) &&
100 	    nfsd_call_nfscommon != NULL)
101 		error = (*nfsd_call_nfscommon)(td, uap);
102 	else if ((uap->flag & (NFSSVC_NFSDNFSD | NFSSVC_NFSDADDSOCK |
103 	    NFSSVC_PUBLICFH | NFSSVC_V4ROOTEXPORT | NFSSVC_NOPUBLICFH |
104 	    NFSSVC_STABLERESTART | NFSSVC_ADMINREVOKE |
105 	    NFSSVC_DUMPCLIENTS | NFSSVC_DUMPLOCKS | NFSSVC_BACKUPSTABLE)) &&
106 	    nfsd_call_nfsd != NULL)
107 		error = (*nfsd_call_nfsd)(td, uap);
108 	if (error == EINTR || error == ERESTART)
109 		error = 0;
110 	return (error);
111 }
112 
113 /*
114  * Called once to initialize data structures...
115  */
116 static int
117 nfssvc_modevent(module_t mod, int type, void *data)
118 {
119 	static int registered;
120 	int error = 0;
121 
122 	switch (type) {
123 	case MOD_LOAD:
124 		error = syscall_register(&nfssvc_offset, &nfssvc_sysent,
125 		    &nfssvc_prev_sysent);
126 		if (error)
127 			break;
128 		registered = 1;
129 		break;
130 
131 	case MOD_UNLOAD:
132 		if (nfsd_call_nfsserver != NULL || nfsd_call_nfscommon != NULL
133 		    || nfsd_call_nfscl != NULL || nfsd_call_nfsd != NULL) {
134 			error = EBUSY;
135 			break;
136 		}
137 		if (registered)
138 			syscall_deregister(&nfssvc_offset, &nfssvc_prev_sysent);
139 		registered = 0;
140 		break;
141 	default:
142 		error = EOPNOTSUPP;
143 		break;
144 	}
145 	return error;
146 }
147 static moduledata_t nfssvc_mod = {
148 	"nfssvc",
149 	nfssvc_modevent,
150 	NULL,
151 };
152 DECLARE_MODULE(nfssvc, nfssvc_mod, SI_SUB_VFS, SI_ORDER_ANY);
153 
154 /* So that loader and kldload(2) can find us, wherever we are.. */
155 MODULE_VERSION(nfssvc, 1);
156 
157