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-rw-r--r--fs/reiserfs/xattr_acl.c571
1 files changed, 571 insertions, 0 deletions
diff --git a/fs/reiserfs/xattr_acl.c b/fs/reiserfs/xattr_acl.c
new file mode 100644
index 0000000..e302071
--- /dev/null
+++ b/fs/reiserfs/xattr_acl.c
@@ -0,0 +1,571 @@
+#include <linux/fs.h>
+#include <linux/posix_acl.h>
+#include <linux/reiserfs_fs.h>
+#include <linux/errno.h>
+#include <linux/pagemap.h>
+#include <linux/xattr.h>
+#include <linux/xattr_acl.h>
+#include <linux/reiserfs_xattr.h>
+#include <linux/reiserfs_acl.h>
+#include <asm/uaccess.h>
+
+static int reiserfs_set_acl(struct inode *inode, int type, struct posix_acl *acl);
+
+static int
+xattr_set_acl(struct inode *inode, int type, const void *value, size_t size)
+{
+ struct posix_acl *acl;
+ int error;
+
+ if (!reiserfs_posixacl(inode->i_sb))
+ return -EOPNOTSUPP;
+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
+ return -EPERM;
+
+ if (value) {
+ acl = posix_acl_from_xattr(value, size);
+ if (IS_ERR(acl)) {
+ return PTR_ERR(acl);
+ } else if (acl) {
+ error = posix_acl_valid(acl);
+ if (error)
+ goto release_and_out;
+ }
+ } else
+ acl = NULL;
+
+ error = reiserfs_set_acl (inode, type, acl);
+
+release_and_out:
+ posix_acl_release(acl);
+ return error;
+}
+
+
+static int
+xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
+{
+ struct posix_acl *acl;
+ int error;
+
+ if (!reiserfs_posixacl(inode->i_sb))
+ return -EOPNOTSUPP;
+
+ acl = reiserfs_get_acl (inode, type);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ if (acl == NULL)
+ return -ENODATA;
+ error = posix_acl_to_xattr(acl, buffer, size);
+ posix_acl_release(acl);
+
+ return error;
+}
+
+
+/*
+ * Convert from filesystem to in-memory representation.
+ */
+static struct posix_acl *
+posix_acl_from_disk(const void *value, size_t size)
+{
+ const char *end = (char *)value + size;
+ int n, count;
+ struct posix_acl *acl;
+
+ if (!value)
+ return NULL;
+ if (size < sizeof(reiserfs_acl_header))
+ return ERR_PTR(-EINVAL);
+ if (((reiserfs_acl_header *)value)->a_version !=
+ cpu_to_le32(REISERFS_ACL_VERSION))
+ return ERR_PTR(-EINVAL);
+ value = (char *)value + sizeof(reiserfs_acl_header);
+ count = reiserfs_acl_count(size);
+ if (count < 0)
+ return ERR_PTR(-EINVAL);
+ if (count == 0)
+ return NULL;
+ acl = posix_acl_alloc(count, GFP_NOFS);
+ if (!acl)
+ return ERR_PTR(-ENOMEM);
+ for (n=0; n < count; n++) {
+ reiserfs_acl_entry *entry =
+ (reiserfs_acl_entry *)value;
+ if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
+ goto fail;
+ acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
+ acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
+ switch(acl->a_entries[n].e_tag) {
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ value = (char *)value +
+ sizeof(reiserfs_acl_entry_short);
+ acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
+ break;
+
+ case ACL_USER:
+ case ACL_GROUP:
+ value = (char *)value + sizeof(reiserfs_acl_entry);
+ if ((char *)value > end)
+ goto fail;
+ acl->a_entries[n].e_id =
+ le32_to_cpu(entry->e_id);
+ break;
+
+ default:
+ goto fail;
+ }
+ }
+ if (value != end)
+ goto fail;
+ return acl;
+
+fail:
+ posix_acl_release(acl);
+ return ERR_PTR(-EINVAL);
+}
+
+/*
+ * Convert from in-memory to filesystem representation.
+ */
+static void *
+posix_acl_to_disk(const struct posix_acl *acl, size_t *size)
+{
+ reiserfs_acl_header *ext_acl;
+ char *e;
+ int n;
+
+ *size = reiserfs_acl_size(acl->a_count);
+ ext_acl = (reiserfs_acl_header *)kmalloc(sizeof(reiserfs_acl_header) +
+ acl->a_count * sizeof(reiserfs_acl_entry), GFP_NOFS);
+ if (!ext_acl)
+ return ERR_PTR(-ENOMEM);
+ ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
+ e = (char *)ext_acl + sizeof(reiserfs_acl_header);
+ for (n=0; n < acl->a_count; n++) {
+ reiserfs_acl_entry *entry = (reiserfs_acl_entry *)e;
+ entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
+ entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
+ switch(acl->a_entries[n].e_tag) {
+ case ACL_USER:
+ case ACL_GROUP:
+ entry->e_id =
+ cpu_to_le32(acl->a_entries[n].e_id);
+ e += sizeof(reiserfs_acl_entry);
+ break;
+
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ e += sizeof(reiserfs_acl_entry_short);
+ break;
+
+ default:
+ goto fail;
+ }
+ }
+ return (char *)ext_acl;
+
+fail:
+ kfree(ext_acl);
+ return ERR_PTR(-EINVAL);
+}
+
+/*
+ * Inode operation get_posix_acl().
+ *
+ * inode->i_sem: down
+ * BKL held [before 2.5.x]
+ */
+struct posix_acl *
+reiserfs_get_acl(struct inode *inode, int type)
+{
+ char *name, *value;
+ struct posix_acl *acl, **p_acl;
+ size_t size;
+ int retval;
+ struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
+
+ switch (type) {
+ case ACL_TYPE_ACCESS:
+ name = XATTR_NAME_ACL_ACCESS;
+ p_acl = &reiserfs_i->i_acl_access;
+ break;
+ case ACL_TYPE_DEFAULT:
+ name = XATTR_NAME_ACL_DEFAULT;
+ p_acl = &reiserfs_i->i_acl_default;
+ break;
+ default:
+ return ERR_PTR (-EINVAL);
+ }
+
+ if (IS_ERR (*p_acl)) {
+ if (PTR_ERR (*p_acl) == -ENODATA)
+ return NULL;
+ } else if (*p_acl != NULL)
+ return posix_acl_dup (*p_acl);
+
+ size = reiserfs_xattr_get (inode, name, NULL, 0);
+ if ((int)size < 0) {
+ if (size == -ENODATA || size == -ENOSYS) {
+ *p_acl = ERR_PTR (-ENODATA);
+ return NULL;
+ }
+ return ERR_PTR (size);
+ }
+
+ value = kmalloc (size, GFP_NOFS);
+ if (!value)
+ return ERR_PTR (-ENOMEM);
+
+ retval = reiserfs_xattr_get(inode, name, value, size);
+ if (retval == -ENODATA || retval == -ENOSYS) {
+ /* This shouldn't actually happen as it should have
+ been caught above.. but just in case */
+ acl = NULL;
+ *p_acl = ERR_PTR (-ENODATA);
+ } else if (retval < 0) {
+ acl = ERR_PTR(retval);
+ } else {
+ acl = posix_acl_from_disk(value, retval);
+ *p_acl = posix_acl_dup (acl);
+ }
+
+ kfree(value);
+ return acl;
+}
+
+/*
+ * Inode operation set_posix_acl().
+ *
+ * inode->i_sem: down
+ * BKL held [before 2.5.x]
+ */
+static int
+reiserfs_set_acl(struct inode *inode, int type, struct posix_acl *acl)
+{
+ char *name;
+ void *value = NULL;
+ struct posix_acl **p_acl;
+ size_t size;
+ int error;
+ struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
+
+ if (S_ISLNK(inode->i_mode))
+ return -EOPNOTSUPP;
+
+ switch (type) {
+ case ACL_TYPE_ACCESS:
+ name = XATTR_NAME_ACL_ACCESS;
+ p_acl = &reiserfs_i->i_acl_access;
+ if (acl) {
+ mode_t mode = inode->i_mode;
+ error = posix_acl_equiv_mode (acl, &mode);
+ if (error < 0)
+ return error;
+ else {
+ inode->i_mode = mode;
+ if (error == 0)
+ acl = NULL;
+ }
+ }
+ break;
+ case ACL_TYPE_DEFAULT:
+ name = XATTR_NAME_ACL_DEFAULT;
+ p_acl = &reiserfs_i->i_acl_default;
+ if (!S_ISDIR (inode->i_mode))
+ return acl ? -EACCES : 0;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (acl) {
+ value = posix_acl_to_disk(acl, &size);
+ if (IS_ERR(value))
+ return (int)PTR_ERR(value);
+ error = reiserfs_xattr_set(inode, name, value, size, 0);
+ } else {
+ error = reiserfs_xattr_del (inode, name);
+ if (error == -ENODATA) {
+ /* This may seem odd here, but it means that the ACL was set
+ * with a value representable with mode bits. If there was
+ * an ACL before, reiserfs_xattr_del already dirtied the inode.
+ */
+ mark_inode_dirty (inode);
+ error = 0;
+ }
+ }
+
+ if (value)
+ kfree(value);
+
+ if (!error) {
+ /* Release the old one */
+ if (!IS_ERR (*p_acl) && *p_acl)
+ posix_acl_release (*p_acl);
+
+ if (acl == NULL)
+ *p_acl = ERR_PTR (-ENODATA);
+ else
+ *p_acl = posix_acl_dup (acl);
+ }
+
+ return error;
+}
+
+/* dir->i_sem: down,
+ * inode is new and not released into the wild yet */
+int
+reiserfs_inherit_default_acl (struct inode *dir, struct dentry *dentry, struct inode *inode)
+{
+ struct posix_acl *acl;
+ int err = 0;
+
+ /* ACLs only get applied to files and directories */
+ if (S_ISLNK (inode->i_mode))
+ return 0;
+
+ /* ACLs can only be used on "new" objects, so if it's an old object
+ * there is nothing to inherit from */
+ if (get_inode_sd_version (dir) == STAT_DATA_V1)
+ goto apply_umask;
+
+ /* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
+ * would be useless since permissions are ignored, and a pain because
+ * it introduces locking cycles */
+ if (is_reiserfs_priv_object (dir)) {
+ reiserfs_mark_inode_private (inode);
+ goto apply_umask;
+ }
+
+ acl = reiserfs_get_acl (dir, ACL_TYPE_DEFAULT);
+ if (IS_ERR (acl)) {
+ if (PTR_ERR (acl) == -ENODATA)
+ goto apply_umask;
+ return PTR_ERR (acl);
+ }
+
+ if (acl) {
+ struct posix_acl *acl_copy;
+ mode_t mode = inode->i_mode;
+ int need_acl;
+
+ /* Copy the default ACL to the default ACL of a new directory */
+ if (S_ISDIR (inode->i_mode)) {
+ err = reiserfs_set_acl (inode, ACL_TYPE_DEFAULT, acl);
+ if (err)
+ goto cleanup;
+ }
+
+ /* Now we reconcile the new ACL and the mode,
+ potentially modifying both */
+ acl_copy = posix_acl_clone (acl, GFP_NOFS);
+ if (!acl_copy) {
+ err = -ENOMEM;
+ goto cleanup;
+ }
+
+
+ need_acl = posix_acl_create_masq (acl_copy, &mode);
+ if (need_acl >= 0) {
+ if (mode != inode->i_mode) {
+ inode->i_mode = mode;
+ }
+
+ /* If we need an ACL.. */
+ if (need_acl > 0) {
+ err = reiserfs_set_acl (inode, ACL_TYPE_ACCESS, acl_copy);
+ if (err)
+ goto cleanup_copy;
+ }
+ }
+cleanup_copy:
+ posix_acl_release (acl_copy);
+cleanup:
+ posix_acl_release (acl);
+ } else {
+apply_umask:
+ /* no ACL, apply umask */
+ inode->i_mode &= ~current->fs->umask;
+ }
+
+ return err;
+}
+
+/* Looks up and caches the result of the default ACL.
+ * We do this so that we don't need to carry the xattr_sem into
+ * reiserfs_new_inode if we don't need to */
+int
+reiserfs_cache_default_acl (struct inode *inode)
+{
+ int ret = 0;
+ if (reiserfs_posixacl (inode->i_sb) &&
+ !is_reiserfs_priv_object (inode)) {
+ struct posix_acl *acl;
+ reiserfs_read_lock_xattr_i (inode);
+ reiserfs_read_lock_xattrs (inode->i_sb);
+ acl = reiserfs_get_acl (inode, ACL_TYPE_DEFAULT);
+ reiserfs_read_unlock_xattrs (inode->i_sb);
+ reiserfs_read_unlock_xattr_i (inode);
+ ret = acl ? 1 : 0;
+ posix_acl_release (acl);
+ }
+
+ return ret;
+}
+
+int
+reiserfs_acl_chmod (struct inode *inode)
+{
+ struct posix_acl *acl, *clone;
+ int error;
+
+ if (S_ISLNK(inode->i_mode))
+ return -EOPNOTSUPP;
+
+ if (get_inode_sd_version (inode) == STAT_DATA_V1 ||
+ !reiserfs_posixacl(inode->i_sb))
+ {
+ return 0;
+ }
+
+ reiserfs_read_lock_xattrs (inode->i_sb);
+ acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
+ reiserfs_read_unlock_xattrs (inode->i_sb);
+ if (!acl)
+ return 0;
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ clone = posix_acl_clone(acl, GFP_NOFS);
+ posix_acl_release(acl);
+ if (!clone)
+ return -ENOMEM;
+ error = posix_acl_chmod_masq(clone, inode->i_mode);
+ if (!error) {
+ int lock = !has_xattr_dir (inode);
+ reiserfs_write_lock_xattr_i (inode);
+ if (lock)
+ reiserfs_write_lock_xattrs (inode->i_sb);
+ else
+ reiserfs_read_lock_xattrs (inode->i_sb);
+ error = reiserfs_set_acl(inode, ACL_TYPE_ACCESS, clone);
+ if (lock)
+ reiserfs_write_unlock_xattrs (inode->i_sb);
+ else
+ reiserfs_read_unlock_xattrs (inode->i_sb);
+ reiserfs_write_unlock_xattr_i (inode);
+ }
+ posix_acl_release(clone);
+ return error;
+}
+
+static int
+posix_acl_access_get(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ if (strlen(name) != sizeof(XATTR_NAME_ACL_ACCESS)-1)
+ return -EINVAL;
+ return xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
+}
+
+static int
+posix_acl_access_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strlen(name) != sizeof(XATTR_NAME_ACL_ACCESS)-1)
+ return -EINVAL;
+ return xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
+}
+
+static int
+posix_acl_access_del (struct inode *inode, const char *name)
+{
+ struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
+ struct posix_acl **acl = &reiserfs_i->i_acl_access;
+ if (strlen(name) != sizeof(XATTR_NAME_ACL_ACCESS)-1)
+ return -EINVAL;
+ if (!IS_ERR (*acl) && *acl) {
+ posix_acl_release (*acl);
+ *acl = ERR_PTR (-ENODATA);
+ }
+
+ return 0;
+}
+
+static int
+posix_acl_access_list (struct inode *inode, const char *name, int namelen, char *out)
+{
+ int len = namelen;
+ if (!reiserfs_posixacl (inode->i_sb))
+ return 0;
+ if (out)
+ memcpy (out, name, len);
+
+ return len;
+}
+
+struct reiserfs_xattr_handler posix_acl_access_handler = {
+ .prefix = XATTR_NAME_ACL_ACCESS,
+ .get = posix_acl_access_get,
+ .set = posix_acl_access_set,
+ .del = posix_acl_access_del,
+ .list = posix_acl_access_list,
+};
+
+static int
+posix_acl_default_get (struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ if (strlen(name) != sizeof(XATTR_NAME_ACL_DEFAULT)-1)
+ return -EINVAL;
+ return xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
+}
+
+static int
+posix_acl_default_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strlen(name) != sizeof(XATTR_NAME_ACL_DEFAULT)-1)
+ return -EINVAL;
+ return xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
+}
+
+static int
+posix_acl_default_del (struct inode *inode, const char *name)
+{
+ struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
+ struct posix_acl **acl = &reiserfs_i->i_acl_default;
+ if (strlen(name) != sizeof(XATTR_NAME_ACL_DEFAULT)-1)
+ return -EINVAL;
+ if (!IS_ERR (*acl) && *acl) {
+ posix_acl_release (*acl);
+ *acl = ERR_PTR (-ENODATA);
+ }
+
+ return 0;
+}
+
+static int
+posix_acl_default_list (struct inode *inode, const char *name, int namelen, char *out)
+{
+ int len = namelen;
+ if (!reiserfs_posixacl (inode->i_sb))
+ return 0;
+ if (out)
+ memcpy (out, name, len);
+
+ return len;
+}
+
+struct reiserfs_xattr_handler posix_acl_default_handler = {
+ .prefix = XATTR_NAME_ACL_DEFAULT,
+ .get = posix_acl_default_get,
+ .set = posix_acl_default_set,
+ .del = posix_acl_default_del,
+ .list = posix_acl_default_list,
+};
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