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 <linux/lm_interface.h>
  18 #include <asm/uaccess.h>
  19
  20 #include "gfs2.h"
  21 #include "incore.h"
  22 #include "acl.h"
  23 #include "eaops.h"
  24 #include "eattr.h"
  25 #include "util.h"
  26
  27 /**
  28  * gfs2_ea_name2type - get the type of the ea, and truncate type from the name
  29  * @namep: ea name, possibly with type appended
  30  *
  31  * Returns: GFS2_EATYPE_XXX
  32  */
  33
  34 unsigned int gfs2_ea_name2type(const char *name, const char **truncated_name)
  35 {
  36         unsigned int type;
  37
  38         if (strncmp(name, "system.", 7) == 0) {
  39                 type = GFS2_EATYPE_SYS;
  40                 if (truncated_name)
  41                         *truncated_name = name + sizeof("system.") - 1;
  42         } else if (strncmp(name, "user.", 5) == 0) {
  43                 type = GFS2_EATYPE_USR;
  44                 if (truncated_name)
  45                         *truncated_name = name + sizeof("user.") - 1;
  46         } else if (strncmp(name, "security.", 9) == 0) {
  47                 type = GFS2_EATYPE_SECURITY;
  48                 if (truncated_name)
  49                         *truncated_name = name + sizeof("security.") - 1;
  50         } else {
  51                 type = GFS2_EATYPE_UNUSED;
  52                 if (truncated_name)
  53                         *truncated_name = NULL;
  54         }
  55
  56         return type;
  57 }
  58
  59 static int system_eo_get(struct gfs2_inode *ip, struct gfs2_ea_request *er)
  60 {
  61         if (!GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len) &&
  62             !GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len) &&
  63             !capable(CAP_SYS_ADMIN))
  64                 return -EPERM;
  65
  66         if (GFS2_SB(&ip->i_inode)->sd_args.ar_posix_acl == 0 &&
  67             (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len) ||
  68              GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)))
  69                 return -EOPNOTSUPP;
  70
  71         return gfs2_ea_get_i(ip, er);
  72 }
  73
  74 static int system_eo_set(struct gfs2_inode *ip, struct gfs2_ea_request *er)
  75 {
  76         int remove = 0;
  77         int error;
  78
  79         if (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len)) {
  80                 if (!(er->er_flags & GFS2_ERF_MODE)) {
  81                         er->er_mode = ip->i_inode.i_mode;
  82                         er->er_flags |= GFS2_ERF_MODE;
  83                 }
  84                 error = gfs2_acl_validate_set(ip, 1, er,
  85                                               &remove, &er->er_mode);
  86                 if (error)
  87                         return error;
  88                 error = gfs2_ea_set_i(ip, er);
  89                 if (error)
  90                         return error;
  91                 if (remove)
  92                         gfs2_ea_remove_i(ip, er);
  93                 return 0;
  94
  95         } else if (GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)) {
  96                 error = gfs2_acl_validate_set(ip, 0, er,
  97                                               &remove, NULL);
  98                 if (error)
  99                         return error;
 100                 if (!remove)
 101                         error = gfs2_ea_set_i(ip, er);
 102                 else {
 103                         error = gfs2_ea_remove_i(ip, er);
 104                         if (error == -ENODATA)
 105                                 error = 0;
 106                 }
 107                 return error;
 108         }
 109
 110         return -EPERM;
 111 }
 112
 113 static int system_eo_remove(struct gfs2_inode *ip, struct gfs2_ea_request *er)
 114 {
 115         if (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len)) {
 116                 int error = gfs2_acl_validate_remove(ip, 1);
 117                 if (error)
 118                         return error;
 119
 120         } else if (GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)) {
 121                 int error = gfs2_acl_validate_remove(ip, 0);
 122                 if (error)
 123                         return error;
 124
 125         } else
 126                 return -EPERM;
 127
 128         return gfs2_ea_remove_i(ip, er);
 129 }
 130
 131 static const struct gfs2_eattr_operations gfs2_user_eaops = {
 132         .eo_get = gfs2_ea_get_i,
 133         .eo_set = gfs2_ea_set_i,
 134         .eo_remove = gfs2_ea_remove_i,
 135         .eo_name = "user",
 136 };
 137
 138 const struct gfs2_eattr_operations gfs2_system_eaops = {
 139         .eo_get = system_eo_get,
 140         .eo_set = system_eo_set,
 141         .eo_remove = system_eo_remove,
 142         .eo_name = "system",
 143 };
 144
 145 static const struct gfs2_eattr_operations gfs2_security_eaops = {
 146         .eo_get = gfs2_ea_get_i,
 147         .eo_set = gfs2_ea_set_i,
 148         .eo_remove = gfs2_ea_remove_i,
 149         .eo_name = "security",
 150 };
 151
 152 const struct gfs2_eattr_operations *gfs2_ea_ops[] = {
 153         NULL,
 154         &gfs2_user_eaops,
 155         &gfs2_system_eaops,
 156         &gfs2_security_eaops,
 157 };
 158