fs/gfs2/eaops.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2005 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 v.2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/xattr.h>
  16 #include <asm/semaphore.h>
  17 #include <asm/uaccess.h>
  18
  19 #include "gfs2.h"
  20 #include "acl.h"
  21 #include "eaops.h"
  22 #include "eattr.h"
  23
  24 /**
  25  * gfs2_ea_name2type - get the type of the ea, and truncate type from the name
  26  * @namep: ea name, possibly with type appended
  27  *
  28  * Returns: GFS2_EATYPE_XXX
  29  */
  30
  31 unsigned int gfs2_ea_name2type(const char *name, char **truncated_name)
  32 {
  33         unsigned int type;
  34
  35         if (strncmp(name, "system.", 7) == 0) {
  36                 type = GFS2_EATYPE_SYS;
  37                 if (truncated_name)
  38                         *truncated_name = strchr(name, '.') + 1;
  39         } else if (strncmp(name, "user.", 5) == 0) {
  40                 type = GFS2_EATYPE_USR;
  41                 if (truncated_name)
  42                         *truncated_name = strchr(name, '.') + 1;
  43         } else {
  44                 type = GFS2_EATYPE_UNUSED;
  45                 if (truncated_name)
  46                         *truncated_name = NULL;
  47         }
  48
  49         return type;
  50 }
  51
  52 static int user_eo_get(struct gfs2_inode *ip, struct gfs2_ea_request *er)
  53 {
  54         struct inode *inode = ip->i_vnode;
  55         int error = permission(inode, MAY_READ, NULL);
  56         if (error)
  57                 return error;
  58
  59         return gfs2_ea_get_i(ip, er);
  60 }
  61
  62 static int user_eo_set(struct gfs2_inode *ip, struct gfs2_ea_request *er)
  63 {
  64         struct inode *inode = ip->i_vnode;
  65
  66         if (S_ISREG(inode->i_mode) ||
  67             (S_ISDIR(inode->i_mode) && !(inode->i_mode & S_ISVTX))) {
  68                 int error = permission(inode, MAY_WRITE, NULL);
  69                 if (error)
  70                         return error;
  71         } else
  72                 return -EPERM;
  73
  74         return gfs2_ea_set_i(ip, er);
  75 }
  76
  77 static int user_eo_remove(struct gfs2_inode *ip, struct gfs2_ea_request *er)
  78 {
  79         struct inode *inode = ip->i_vnode;
  80
  81         if (S_ISREG(inode->i_mode) ||
  82             (S_ISDIR(inode->i_mode) && !(inode->i_mode & S_ISVTX))) {
  83                 int error = permission(inode, MAY_WRITE, NULL);
  84                 if (error)
  85                         return error;
  86         } else
  87                 return -EPERM;
  88
  89         return gfs2_ea_remove_i(ip, er);
  90 }
  91
  92 static int system_eo_get(struct gfs2_inode *ip, struct gfs2_ea_request *er)
  93 {
  94         if (!GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len) &&
  95             !GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len) &&
  96             !capable(CAP_SYS_ADMIN))
  97                 return -EPERM;
  98
  99         if (ip->i_sbd->sd_args.ar_posix_acl == 0 &&
 100             (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len) ||
 101              GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)))
 102                 return -EOPNOTSUPP;
 103
 104
 105
 106         return gfs2_ea_get_i(ip, er);
 107 }
 108
 109 static int system_eo_set(struct gfs2_inode *ip, struct gfs2_ea_request *er)
 110 {
 111         int remove = 0;
 112         int error;
 113
 114         if (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len)) {
 115                 if (!(er->er_flags & GFS2_ERF_MODE)) {
 116                         er->er_mode = ip->i_di.di_mode;
 117                         er->er_flags |= GFS2_ERF_MODE;
 118                 }
 119                 error = gfs2_acl_validate_set(ip, 1, er,
 120                                               &remove, &er->er_mode);
 121                 if (error)
 122                         return error;
 123                 error = gfs2_ea_set_i(ip, er);
 124                 if (error)
 125                         return error;
 126                 if (remove)
 127                         gfs2_ea_remove_i(ip, er);
 128                 return 0;
 129
 130         } else if (GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)) {
 131                 error = gfs2_acl_validate_set(ip, 0, er,
 132                                               &remove, NULL);
 133                 if (error)
 134                         return error;
 135                 if (!remove)
 136                         error = gfs2_ea_set_i(ip, er);
 137                 else {
 138                         error = gfs2_ea_remove_i(ip, er);
 139                         if (error == -ENODATA)
 140                                 error = 0;
 141                 }
 142                 return error;
 143         }
 144
 145         return -EPERM;
 146 }
 147
 148 static int system_eo_remove(struct gfs2_inode *ip, struct gfs2_ea_request *er)
 149 {
 150         if (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len)) {
 151                 int error = gfs2_acl_validate_remove(ip, 1);
 152                 if (error)
 153                         return error;
 154
 155         } else if (GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)) {
 156                 int error = gfs2_acl_validate_remove(ip, 0);
 157                 if (error)
 158                         return error;
 159
 160         } else
 161                 return -EPERM;
 162
 163         return gfs2_ea_remove_i(ip, er);
 164 }
 165
 166 struct gfs2_eattr_operations gfs2_user_eaops = {
 167         .eo_get = user_eo_get,
 168         .eo_set = user_eo_set,
 169         .eo_remove = user_eo_remove,
 170         .eo_name = "user",
 171 };
 172
 173 struct gfs2_eattr_operations gfs2_system_eaops = {
 174         .eo_get = system_eo_get,
 175         .eo_set = system_eo_set,
 176         .eo_remove = system_eo_remove,
 177         .eo_name = "system",
 178 };
 179
 180 struct gfs2_eattr_operations *gfs2_ea_ops[] = {
 181         NULL,
 182         &gfs2_user_eaops,
 183         &gfs2_system_eaops,
 184 };
 185