hfsplus: rework functionality of getting, setting and deleting of extended attributes

Rework functionality of getting, setting and deleting of extended attributes.
Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Reported-by: Hin-Tak Leung <htl10@users.sourceforge.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hfsplus/xattr.h

+/*
+ * linux/fs/hfsplus/xattr.h
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Logic of processing extended attributes
+ */
+
+#ifndef _LINUX_HFSPLUS_XATTR_H
+#define _LINUX_HFSPLUS_XATTR_H
+
+#include <linux/xattr.h>
+
+extern const struct xattr_handler hfsplus_xattr_osx_handler;
+extern const struct xattr_handler hfsplus_xattr_user_handler;
+extern const struct xattr_handler hfsplus_xattr_trusted_handler;
+/*extern const struct xattr_handler hfsplus_xattr_acl_access_handler;*/
+/*extern const struct xattr_handler hfsplus_xattr_acl_default_handler;*/
+extern const struct xattr_handler hfsplus_xattr_security_handler;
+
+extern const struct xattr_handler *hfsplus_xattr_handlers[];
+
+int __hfsplus_setxattr(struct inode *inode, const char *name,
+			const void *value, size_t size, int flags);
+
+static inline int hfsplus_setxattr(struct dentry *dentry, const char *name,
+			const void *value, size_t size, int flags)
+{
+	return __hfsplus_setxattr(dentry->d_inode, name, value, size, flags);
+}
+
+ssize_t hfsplus_getxattr(struct dentry *dentry, const char *name,
+			void *value, size_t size);
+
+ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size);
+
+int hfsplus_removexattr(struct dentry *dentry, const char *name);
+
+int hfsplus_init_security(struct inode *inode, struct inode *dir,
+				const struct qstr *qstr);
+
+static inline int hfsplus_init_acl(struct inode *inode, struct inode *dir)
+{
+	/*TODO: implement*/
+	return 0;
+}
+
+static inline int hfsplus_init_inode_security(struct inode *inode,
+						struct inode *dir,
+						const struct qstr *qstr)
+{
+	int err;
+
+	err = hfsplus_init_acl(inode, dir);
+	if (!err)
+		err = hfsplus_init_security(inode, dir, qstr);
+	return err;
+}
+
+#endif

fs/hfsplus/xattr_security.c

+/*
+ * linux/fs/hfsplus/xattr_trusted.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Handler for storing security labels as extended attributes.
+ */
+
+#include <linux/security.h>
+#include "hfsplus_fs.h"
+#include "xattr.h"
+
+static int hfsplus_security_getxattr(struct dentry *dentry, const char *name,
+					void *buffer, size_t size, int type)
+{
+	char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+	size_t len = strlen(name);
+
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	if (len + XATTR_SECURITY_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
+		return -EOPNOTSUPP;
+
+	strcpy(xattr_name, XATTR_SECURITY_PREFIX);
+	strcpy(xattr_name + XATTR_SECURITY_PREFIX_LEN, name);
+
+	return hfsplus_getxattr(dentry, xattr_name, buffer, size);
+}
+
+static int hfsplus_security_setxattr(struct dentry *dentry, const char *name,
+		const void *buffer, size_t size, int flags, int type)
+{
+	char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+	size_t len = strlen(name);
+
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	if (len + XATTR_SECURITY_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
+		return -EOPNOTSUPP;
+
+	strcpy(xattr_name, XATTR_SECURITY_PREFIX);
+	strcpy(xattr_name + XATTR_SECURITY_PREFIX_LEN, name);
+
+	return hfsplus_setxattr(dentry, xattr_name, buffer, size, flags);
+}
+
+static size_t hfsplus_security_listxattr(struct dentry *dentry, char *list,
+		size_t list_size, const char *name, size_t name_len, int type)
+{
+	/*
+	 * This method is not used.
+	 * It is used hfsplus_listxattr() instead of generic_listxattr().
+	 */
+	return -EOPNOTSUPP;
+}
+
+static int hfsplus_initxattrs(struct inode *inode,
+				const struct xattr *xattr_array,
+				void *fs_info)
+{
+	const struct xattr *xattr;
+	char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+	size_t xattr_name_len;
+	int err = 0;
+
+	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+		xattr_name_len = strlen(xattr->name);
+
+		if (xattr_name_len == 0)
+			continue;
+
+		if (xattr_name_len + XATTR_SECURITY_PREFIX_LEN >
+				HFSPLUS_ATTR_MAX_STRLEN)
+			return -EOPNOTSUPP;
+
+		strcpy(xattr_name, XATTR_SECURITY_PREFIX);
+		strcpy(xattr_name +
+			XATTR_SECURITY_PREFIX_LEN, xattr->name);
+		memset(xattr_name +
+			XATTR_SECURITY_PREFIX_LEN + xattr_name_len, 0, 1);
+
+		err = __hfsplus_setxattr(inode, xattr_name,
+					xattr->value, xattr->value_len, 0);
+		if (err)
+			break;
+	}
+	return err;
+}
+
+int hfsplus_init_security(struct inode *inode, struct inode *dir,
+				const struct qstr *qstr)
+{
+	return security_inode_init_security(inode, dir, qstr,
+					&hfsplus_initxattrs, NULL);
+}
+
+const struct xattr_handler hfsplus_xattr_security_handler = {
+	.prefix	= XATTR_SECURITY_PREFIX,
+	.list	= hfsplus_security_listxattr,
+	.get	= hfsplus_security_getxattr,
+	.set	= hfsplus_security_setxattr,
+};

fs/hfsplus/xattr_trusted.c

+/*
+ * linux/fs/hfsplus/xattr_trusted.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Handler for trusted extended attributes.
+ */
+
+#include "hfsplus_fs.h"
+#include "xattr.h"
+
+static int hfsplus_trusted_getxattr(struct dentry *dentry, const char *name,
+					void *buffer, size_t size, int type)
+{
+	char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+	size_t len = strlen(name);
+
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	if (len + XATTR_TRUSTED_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
+		return -EOPNOTSUPP;
+
+	strcpy(xattr_name, XATTR_TRUSTED_PREFIX);
+	strcpy(xattr_name + XATTR_TRUSTED_PREFIX_LEN, name);
+
+	return hfsplus_getxattr(dentry, xattr_name, buffer, size);
+}
+
+static int hfsplus_trusted_setxattr(struct dentry *dentry, const char *name,
+		const void *buffer, size_t size, int flags, int type)
+{
+	char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+	size_t len = strlen(name);
+
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	if (len + XATTR_TRUSTED_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
+		return -EOPNOTSUPP;
+
+	strcpy(xattr_name, XATTR_TRUSTED_PREFIX);
+	strcpy(xattr_name + XATTR_TRUSTED_PREFIX_LEN, name);
+
+	return hfsplus_setxattr(dentry, xattr_name, buffer, size, flags);
+}
+
+static size_t hfsplus_trusted_listxattr(struct dentry *dentry, char *list,
+		size_t list_size, const char *name, size_t name_len, int type)
+{
+	/*
+	 * This method is not used.
+	 * It is used hfsplus_listxattr() instead of generic_listxattr().
+	 */
+	return -EOPNOTSUPP;
+}
+
+const struct xattr_handler hfsplus_xattr_trusted_handler = {
+	.prefix	= XATTR_TRUSTED_PREFIX,
+	.list	= hfsplus_trusted_listxattr,
+	.get	= hfsplus_trusted_getxattr,
+	.set	= hfsplus_trusted_setxattr,
+};

fs/hfsplus/xattr_user.c

+/*
+ * linux/fs/hfsplus/xattr_user.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Handler for user extended attributes.
+ */
+
+#include "hfsplus_fs.h"
+#include "xattr.h"
+
+static int hfsplus_user_getxattr(struct dentry *dentry, const char *name,
+					void *buffer, size_t size, int type)
+{
+	char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+	size_t len = strlen(name);
+
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	if (len + XATTR_USER_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
+		return -EOPNOTSUPP;
+
+	strcpy(xattr_name, XATTR_USER_PREFIX);
+	strcpy(xattr_name + XATTR_USER_PREFIX_LEN, name);
+
+	return hfsplus_getxattr(dentry, xattr_name, buffer, size);
+}
+
+static int hfsplus_user_setxattr(struct dentry *dentry, const char *name,
+		const void *buffer, size_t size, int flags, int type)
+{
+	char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+	size_t len = strlen(name);
+
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	if (len + XATTR_USER_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
+		return -EOPNOTSUPP;
+
+	strcpy(xattr_name, XATTR_USER_PREFIX);
+	strcpy(xattr_name + XATTR_USER_PREFIX_LEN, name);
+
+	return hfsplus_setxattr(dentry, xattr_name, buffer, size, flags);
+}
+
+static size_t hfsplus_user_listxattr(struct dentry *dentry, char *list,
+		size_t list_size, const char *name, size_t name_len, int type)
+{
+	/*
+	 * This method is not used.
+	 * It is used hfsplus_listxattr() instead of generic_listxattr().
+	 */
+	return -EOPNOTSUPP;
+}
+
+const struct xattr_handler hfsplus_xattr_user_handler = {
+	.prefix	= XATTR_USER_PREFIX,
+	.list	= hfsplus_user_listxattr,
+	.get	= hfsplus_user_getxattr,
+	.set	= hfsplus_user_setxattr,
+};