xref: /linux/fs/nfsd/auth.c (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
1 /*
2  * linux/fs/nfsd/auth.c
3  *
4  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
5  */
6 
7 #include <linux/types.h>
8 #include <linux/sched.h>
9 #include <linux/sunrpc/svc.h>
10 #include <linux/sunrpc/svcauth.h>
11 #include <linux/nfsd/nfsd.h>
12 #include <linux/nfsd/export.h>
13 #include "auth.h"
14 
15 int nfsexp_flags(struct svc_rqst *rqstp, struct svc_export *exp)
16 {
17 	struct exp_flavor_info *f;
18 	struct exp_flavor_info *end = exp->ex_flavors + exp->ex_nflavors;
19 
20 	for (f = exp->ex_flavors; f < end; f++) {
21 		if (f->pseudoflavor == rqstp->rq_flavor)
22 			return f->flags;
23 	}
24 	return exp->ex_flags;
25 
26 }
27 
28 int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp)
29 {
30 	struct svc_cred	cred = rqstp->rq_cred;
31 	int i;
32 	int flags = nfsexp_flags(rqstp, exp);
33 	int ret;
34 
35 	if (flags & NFSEXP_ALLSQUASH) {
36 		cred.cr_uid = exp->ex_anon_uid;
37 		cred.cr_gid = exp->ex_anon_gid;
38 		cred.cr_group_info = groups_alloc(0);
39 	} else if (flags & NFSEXP_ROOTSQUASH) {
40 		struct group_info *gi;
41 		if (!cred.cr_uid)
42 			cred.cr_uid = exp->ex_anon_uid;
43 		if (!cred.cr_gid)
44 			cred.cr_gid = exp->ex_anon_gid;
45 		gi = groups_alloc(cred.cr_group_info->ngroups);
46 		if (gi)
47 			for (i = 0; i < cred.cr_group_info->ngroups; i++) {
48 				if (!GROUP_AT(cred.cr_group_info, i))
49 					GROUP_AT(gi, i) = exp->ex_anon_gid;
50 				else
51 					GROUP_AT(gi, i) = GROUP_AT(cred.cr_group_info, i);
52 			}
53 		cred.cr_group_info = gi;
54 	} else
55 		get_group_info(cred.cr_group_info);
56 
57 	if (cred.cr_uid != (uid_t) -1)
58 		current->fsuid = cred.cr_uid;
59 	else
60 		current->fsuid = exp->ex_anon_uid;
61 	if (cred.cr_gid != (gid_t) -1)
62 		current->fsgid = cred.cr_gid;
63 	else
64 		current->fsgid = exp->ex_anon_gid;
65 
66 	if (!cred.cr_group_info)
67 		return -ENOMEM;
68 	ret = set_current_groups(cred.cr_group_info);
69 	put_group_info(cred.cr_group_info);
70 	if ((cred.cr_uid)) {
71 		current->cap_effective =
72 			cap_drop_nfsd_set(current->cap_effective);
73 	} else {
74 		current->cap_effective =
75 			cap_raise_nfsd_set(current->cap_effective,
76 					   current->cap_permitted);
77 	}
78 	return ret;
79 }
80