xref: /freebsd/sys/nfs/nfs_nfssvc.c (revision 4c8945a06b01a5c8122cdeb402af36bb46a06acc)
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 	error = priv_check(td, PRIV_NFS_DAEMON);
85 	if (error)
86 		return (error);
87 	error = EINVAL;
88 	if ((uap->flag & (NFSSVC_ADDSOCK | NFSSVC_OLDNFSD | NFSSVC_NFSD)) &&
89 	    nfsd_call_nfsserver != NULL)
90 		error = (*nfsd_call_nfsserver)(td, uap);
91 	else if ((uap->flag & (NFSSVC_CBADDSOCK | NFSSVC_NFSCBD)) &&
92 	    nfsd_call_nfscl != NULL)
93 		error = (*nfsd_call_nfscl)(td, uap);
94 	else if ((uap->flag & (NFSSVC_IDNAME | NFSSVC_GETSTATS |
95 	    NFSSVC_GSSDADDPORT | NFSSVC_GSSDADDFIRST | NFSSVC_GSSDDELETEALL |
96 	    NFSSVC_NFSUSERDPORT | NFSSVC_NFSUSERDDELPORT)) &&
97 	    nfsd_call_nfscommon != NULL)
98 		error = (*nfsd_call_nfscommon)(td, uap);
99 	else if ((uap->flag & (NFSSVC_NFSDNFSD | NFSSVC_NFSDADDSOCK |
100 	    NFSSVC_PUBLICFH | NFSSVC_V4ROOTEXPORT | NFSSVC_NOPUBLICFH |
101 	    NFSSVC_STABLERESTART | NFSSVC_ADMINREVOKE |
102 	    NFSSVC_DUMPCLIENTS | NFSSVC_DUMPLOCKS)) &&
103 	    nfsd_call_nfsd != NULL)
104 		error = (*nfsd_call_nfsd)(td, uap);
105 	if (error == EINTR || error == ERESTART)
106 		error = 0;
107 	return (error);
108 }
109 
110 /*
111  * Called once to initialize data structures...
112  */
113 static int
114 nfssvc_modevent(module_t mod, int type, void *data)
115 {
116 	static int registered;
117 	int error = 0;
118 
119 	switch (type) {
120 	case MOD_LOAD:
121 		error = syscall_register(&nfssvc_offset, &nfssvc_sysent,
122 		    &nfssvc_prev_sysent);
123 		if (error)
124 			break;
125 		registered = 1;
126 		break;
127 
128 	case MOD_UNLOAD:
129 		if (nfsd_call_nfsserver != NULL || nfsd_call_nfscommon != NULL
130 		    || nfsd_call_nfscl != NULL || nfsd_call_nfsd != NULL) {
131 			error = EBUSY;
132 			break;
133 		}
134 		if (registered)
135 			syscall_deregister(&nfssvc_offset, &nfssvc_prev_sysent);
136 		registered = 0;
137 		break;
138 	default:
139 		error = EOPNOTSUPP;
140 		break;
141 	}
142 	return error;
143 }
144 static moduledata_t nfssvc_mod = {
145 	"nfssvc",
146 	nfssvc_modevent,
147 	NULL,
148 };
149 DECLARE_MODULE(nfssvc, nfssvc_mod, SI_SUB_VFS, SI_ORDER_ANY);
150 
151 /* So that loader and kldload(2) can find us, wherever we are.. */
152 MODULE_VERSION(nfssvc, 1);
153 
154