From: Andreas Gruenbacher Subject: [PATCH v10 18/46] richacl: Add richacl xattr handler Date: Mon, 12 Oct 2015 00:58:29 +0200 Message-ID: <1444604337-17651-19-git-send-email-andreas.gruenbacher@gmail.com> References: <1444604337-17651-1-git-send-email-andreas.gruenbacher@gmail.com> Cc: Andreas Gruenbacher To: Alexander Viro , "Theodore Ts'o" , Andreas Dilger , "J. Bruce Fields" , Jeff Layton , Trond Myklebust , Anna Schumaker , Dave Chinner , linux-ext4@vger.kernel.org, xfs@oss.sgi.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-api@vger.kernel.org Return-path: In-Reply-To: <1444604337-17651-1-git-send-email-andreas.gruenbacher@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org From: Andreas Gruenbacher Add richacl xattr handler implementing the xattr operations based on the get_richacl and set_richacl inode operations. Signed-off-by: Andreas Gruenbacher --- fs/richacl_xattr.c | 78 +++++++++++++++++++++++++++++++++++++++++++ include/linux/richacl_xattr.h | 2 ++ 2 files changed, 80 insertions(+) diff --git a/fs/richacl_xattr.c b/fs/richacl_xattr.c index cd9979d..dc529dc 100644 --- a/fs/richacl_xattr.c +++ b/fs/richacl_xattr.c @@ -18,7 +18,9 @@ #include #include #include +#include #include +#include MODULE_LICENSE("GPL"); @@ -161,6 +163,82 @@ richacl_to_xattr(struct user_namespace *user_ns, } EXPORT_SYMBOL_GPL(richacl_to_xattr); +static size_t +richacl_xattr_list(struct dentry *dentry, char *list, size_t list_len, + const char *name, size_t name_len, int handler_flags) +{ + const size_t size = sizeof(XATTR_NAME_RICHACL); + + if (!IS_RICHACL(d_backing_inode(dentry))) + return 0; + if (list && size <= list_len) + memcpy(list, XATTR_NAME_RICHACL, size); + return size; +} + +static int +richacl_xattr_get(struct dentry *dentry, const char *name, void *buffer, + size_t buffer_size, int handler_flags) +{ + struct inode *inode = d_backing_inode(dentry); + struct richacl *acl; + int error; + + if (strcmp(name, "") != 0) + return -EINVAL; + if (!IS_RICHACL(inode)) + return EOPNOTSUPP; + if (S_ISLNK(inode->i_mode)) + return -EOPNOTSUPP; + acl = get_richacl(inode); + if (IS_ERR(acl)) + return PTR_ERR(acl); + if (acl == NULL) + return -ENODATA; + error = richacl_to_xattr(&init_user_ns, acl, buffer, buffer_size); + richacl_put(acl); + return error; +} + +static int +richacl_xattr_set(struct dentry *dentry, const char *name, + const void *value, size_t size, int flags, int handler_flags) +{ + struct inode *inode = d_backing_inode(dentry); + struct richacl *acl = NULL; + int ret; + + if (strcmp(name, "") != 0) + return -EINVAL; + if (!IS_RICHACL(inode)) + return -EOPNOTSUPP; + if (!inode->i_op->set_richacl) + return -EOPNOTSUPP; + + if (!uid_eq(current_fsuid(), inode->i_uid) && + inode_permission(inode, MAY_CHMOD) && + !capable(CAP_FOWNER)) + return -EPERM; + + if (value) { + acl = richacl_from_xattr(&init_user_ns, value, size); + if (IS_ERR(acl)) + return PTR_ERR(acl); + } + + ret = inode->i_op->set_richacl(inode, acl); + richacl_put(acl); + return ret; +} + +struct xattr_handler richacl_xattr_handler = { + .prefix = XATTR_NAME_RICHACL, + .list = richacl_xattr_list, + .get = richacl_xattr_get, + .set = richacl_xattr_set, +}; +EXPORT_SYMBOL(richacl_xattr_handler); + /* * Fix up the uids and gids in richacl extended attributes in place. */ diff --git a/include/linux/richacl_xattr.h b/include/linux/richacl_xattr.h index f84cc21..dac4e32 100644 --- a/include/linux/richacl_xattr.h +++ b/include/linux/richacl_xattr.h @@ -59,4 +59,6 @@ static inline void richacl_fix_xattr_to_user(void *value, size_t size) } #endif +extern struct xattr_handler richacl_xattr_handler; + #endif /* __RICHACL_XATTR_H */ -- 2.5.0