[RFC][PATCH 09/12] digest_lists: Interfaces - digest_label
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: 2021-06-25 16:58:15
Also in:
linux-integrity, linux-kselftest, linux-security-module, lkml
Subsystem:
documentation, extended verification module (evm), integrity measurement architecture (ima), security subsystem, the rest · Maintainers:
Jonathan Corbet, Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
This patch introduces the digest_label interface. It can be used to set a label to be applied to the next digest list (buffer) loaded through digest_list_add. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> --- Documentation/security/digest_lists.rst | 7 +++++ security/integrity/digest_lists/fs.c | 34 +++++++++++++++++++++++++ 2 files changed, 41 insertions(+)
diff --git a/Documentation/security/digest_lists.rst b/Documentation/security/digest_lists.rst
index 8f245fae6825..d83279046a55 100644
--- a/Documentation/security/digest_lists.rst
+++ b/Documentation/security/digest_lists.rst@@ -683,3 +683,10 @@ other (with .ascii prefix) shows the digest list in ASCII format. Files are added and removed at the same time digest lists are added and removed. + + +``digest_label`` +~~~~~~~~~~~~~~~~ + +``digest_label`` can be used to set a label to be applied to the next +digest list (buffer) loaded ``through digest_list_add``.
diff --git a/security/integrity/digest_lists/fs.c b/security/integrity/digest_lists/fs.c
index f665ef063df7..f6e88fac27bc 100644
--- a/security/integrity/digest_lists/fs.c
+++ b/security/integrity/digest_lists/fs.c@@ -34,6 +34,7 @@ static struct dentry *digest_lists_dir; static struct dentry *digest_lists_loaded_dir; +static struct dentry *digest_label_dentry; static struct dentry *digest_list_add_dentry; static struct dentry *digest_list_del_dentry; char digest_label[NAME_MAX + 1];
@@ -465,6 +466,32 @@ static const struct file_operations digest_list_upload_ops = { .llseek = generic_file_llseek, }; +/* + * digest_label_write: write label for next uploaded digest list. + */ +static ssize_t digest_label_write(struct file *file, const char __user *buf, + size_t datalen, loff_t *ppos) +{ + int rc; + + if (datalen >= sizeof(digest_label)) + return -EINVAL; + + rc = copy_from_user(digest_label, buf, datalen); + if (rc < 0) + return rc; + + digest_label[datalen] = '\0'; + return datalen; +} + +static const struct file_operations digest_label_ops = { + .open = generic_file_open, + .write = digest_label_write, + .read = seq_read, + .llseek = generic_file_llseek, +}; + static int __init digest_lists_fs_init(void) { digest_lists_dir = securityfs_create_dir("digest_lists", integrity_dir);
@@ -488,8 +515,15 @@ static int __init digest_lists_fs_init(void) if (IS_ERR(digest_list_del_dentry)) goto out; + digest_label_dentry = securityfs_create_file("digest_label", 0600, + digest_lists_dir, NULL, + &digest_label_ops); + if (IS_ERR(digest_label_dentry)) + goto out; + return 0; out: + securityfs_remove(digest_label_dentry); securityfs_remove(digest_list_del_dentry); securityfs_remove(digest_list_add_dentry); securityfs_remove(digest_lists_loaded_dir);
--
2.25.1