[PATCH v2 1/2] ima: support to read appraise mode

[Tianjia Zhang <tianjia.zhang@linux.alibaba.com>]

Support to read appraise mode in runtime through securityfs file
'integrity/ima/appraise_mode'.

Signed-off-by: luanshi <zhangliguang@linux.alibaba.com>
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
---
 security/integrity/ima/ima_fs.c | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index a71e822a6e92..65384f6ac0d9 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -360,6 +360,7 @@ static struct dentry *ascii_runtime_measurements;
 static struct dentry *runtime_measurements_count;
 static struct dentry *violations;
 static struct dentry *ima_policy;
+static struct dentry *appraise_mode;
 
 enum ima_fs_flags {
 	IMA_FS_BUSY,
@@ -447,6 +448,29 @@ static const struct file_operations ima_measure_policy_ops = {
 	.llseek = generic_file_llseek,
 };
 
+static ssize_t ima_appraise_mode_read(struct file *filp,
+					char __user *buf,
+					size_t count, loff_t *ppos)
+{
+	const char *mode;
+
+	if (ima_appraise & IMA_APPRAISE_ENFORCE)
+		mode = "enforce";
+	else if (ima_appraise & IMA_APPRAISE_FIX)
+		mode = "fix";
+	else if (ima_appraise & IMA_APPRAISE_LOG)
+		mode = "log";
+	else
+		mode = "off";
+
+	return simple_read_from_buffer(buf, count, ppos, mode, strlen(mode));
+}
+
+static const struct file_operations ima_appraise_mode_ops = {
+	.read = ima_appraise_mode_read,
+	.llseek = generic_file_llseek,
+};
+
 int __init ima_fs_init(void)
 {
 	ima_dir = securityfs_create_dir("ima", integrity_dir);
@@ -491,14 +515,20 @@ int __init ima_fs_init(void)
 	if (IS_ERR(ima_policy))
 		goto out;
 
+	appraise_mode =
+	    securityfs_create_file("appraise_mode", S_IRUSR | S_IRGRP,
+				   ima_dir, NULL, &ima_appraise_mode_ops);
+	if (IS_ERR(appraise_mode))
+		goto out;
+
 	return 0;
 out:
+	securityfs_remove(ima_policy);
 	securityfs_remove(violations);
 	securityfs_remove(runtime_measurements_count);
 	securityfs_remove(ascii_runtime_measurements);
 	securityfs_remove(binary_runtime_measurements);
 	securityfs_remove(ima_symlink);
 	securityfs_remove(ima_dir);
-	securityfs_remove(ima_policy);
 	return -1;
 }
-- 
2.17.1