fs/gfs2/eaops.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License version 2.
   8  */
   9
  10 #include <linux/slab.h>
  11 #include <linux/spinlock.h>
  12 #include <linux/completion.h>
  13 #include <linux/buffer_head.h>
  14 #include <linux/capability.h>
  15 #include <linux/xattr.h>
  16 #include <linux/gfs2_ondisk.h>
  17 #include <asm/uaccess.h>
  18
  19 #include "gfs2.h"
  20 #include "incore.h"
  21 #include "acl.h"
  22 #include "eaops.h"
  23 #include "eattr.h"
  24 #include "util.h"
  25
  26 /**
  27  * gfs2_ea_name2type - get the type of the ea, and truncate type from the name
  28  * @namep: ea name, possibly with type appended
  29  *
  30  * Returns: GFS2_EATYPE_XXX
  31  */
  32
  33 unsigned int gfs2_ea_name2type(const char *name, const char **truncated_name)
  34 {
  35         unsigned int type;
  36
  37         if (strncmp(name, "system.", 7) == 0) {
  38                 type = GFS2_EATYPE_SYS;
  39                 if (truncated_name)
  40                         *truncated_name = name + sizeof("system.") - 1;
  41         } else if (strncmp(name, "user.", 5) == 0) {
  42                 type = GFS2_EATYPE_USR;
  43                 if (truncated_name)
  44                         *truncated_name = name + sizeof("user.") - 1;
  45         } else if (strncmp(name, "security.", 9) == 0) {
  46                 type = GFS2_EATYPE_SECURITY;
  47                 if (truncated_name)
  48                         *truncated_name = name + sizeof("security.") - 1;
  49         } else {
  50                 type = GFS2_EATYPE_UNUSED;
  51                 if (truncated_name)
  52                         *truncated_name = NULL;
  53         }
  54
  55         return type;
  56 }
  57
  58 static int system_eo_get(struct gfs2_inode *ip, struct gfs2_ea_request *er)
  59 {
  60         if (!GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len) &&
  61             !GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len) &&
  62             !capable(CAP_SYS_ADMIN))
  63                 return -EPERM;
  64
  65         if (GFS2_SB(&ip->i_inode)->sd_args.ar_posix_acl == 0 &&
  66             (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len) ||
  67              GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)))
  68                 return -EOPNOTSUPP;
  69
  70         return gfs2_ea_get_i(ip, er);
  71 }
  72
  73 static int system_eo_set(struct gfs2_inode *ip, struct gfs2_ea_request *er)
  74 {
  75         int remove = 0;
  76         int error;
  77
  78         if (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len)) {
  79                 if (!(er->er_flags & GFS2_ERF_MODE)) {
  80                         er->er_mode = ip->i_inode.i_mode;
  81                         er->er_flags |= GFS2_ERF_MODE;
  82                 }
  83                 error = gfs2_acl_validate_set(ip, 1, er,
  84                                               &remove, &er->er_mode);
  85                 if (error)
  86                         return error;
  87                 error = gfs2_ea_set_i(ip, er);
  88                 if (error)
  89                         return error;
  90                 if (remove)
  91                         gfs2_ea_remove_i(ip, er);
  92                 return 0;
  93
  94         } else if (GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)) {
  95                 error = gfs2_acl_validate_set(ip, 0, er,
  96                                               &remove, NULL);
  97                 if (error)
  98                         return error;
  99                 if (!remove)
 100                         error = gfs2_ea_set_i(ip, er);
 101                 else {
 102                         error = gfs2_ea_remove_i(ip, er);
 103                         if (error == -ENODATA)
 104                                 error = 0;
 105                 }
 106                 return error;
 107         }
 108
 109         return -EPERM;
 110 }
 111
 112 static int system_eo_remove(struct gfs2_inode *ip, struct gfs2_ea_request *er)
 113 {
 114         if (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len)) {
 115                 int error = gfs2_acl_validate_remove(ip, 1);
 116                 if (error)
 117                         return error;
 118
 119         } else if (GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)) {
 120                 int error = gfs2_acl_validate_remove(ip, 0);
 121                 if (error)
 122                         return error;
 123
 124         } else
 125                 return -EPERM;
 126
 127         return gfs2_ea_remove_i(ip, er);
 128 }
 129
 130 static const struct gfs2_eattr_operations gfs2_user_eaops = {
 131         .eo_get = gfs2_ea_get_i,
 132         .eo_set = gfs2_ea_set_i,
 133         .eo_remove = gfs2_ea_remove_i,
 134         .eo_name = "user",
 135 };
 136
 137 const struct gfs2_eattr_operations gfs2_system_eaops = {
 138         .eo_get = system_eo_get,
 139         .eo_set = system_eo_set,
 140         .eo_remove = system_eo_remove,
 141         .eo_name = "system",
 142 };
 143
 144 static const struct gfs2_eattr_operations gfs2_security_eaops = {
 145         .eo_get = gfs2_ea_get_i,
 146         .eo_set = gfs2_ea_set_i,
 147         .eo_remove = gfs2_ea_remove_i,
 148         .eo_name = "security",
 149 };
 150
 151 const struct gfs2_eattr_operations *gfs2_ea_ops[] = {
 152         NULL,
 153         &gfs2_user_eaops,
 154         &gfs2_system_eaops,
 155         &gfs2_security_eaops,
 156 };
 157