Expose policy SHA256 checksum via selinuxfs.
Signed-off-by: Sebastien Buisson <sbuisson@xxxxxxx>
---
security/selinux/selinuxfs.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index ce71718..b2d5deb 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -30,6 +30,7 @@
#include <linux/uaccess.h>
#include <linux/kobject.h>
#include <linux/ctype.h>
+#include <crypto/sha.h>
/* selinuxfs pseudo filesystem for exporting the security policy API.
Based on the proc code and the fs/nfsd/nfsctl.c code. */
@@ -99,6 +100,7 @@ enum sel_inos {
SEL_STATUS, /* export current status using mmap() */
SEL_POLICY, /* allow userspace to read the in kernel policy */
SEL_VALIDATE_TRANS, /* compute validatetrans decision */
+ SEL_POLICYCKSUM,/* return policy SHA256 checkum */
SEL_INO_NEXT, /* The next inode number to use */
};
@@ -313,6 +315,22 @@ static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
.llseek = generic_file_llseek,
};
+static ssize_t sel_read_policycksum(struct file *filp, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ size_t tmpbuflen = SHA256_DIGEST_SIZE*2 + 1;
+ char tmpbuf[tmpbuflen];
+ ssize_t length;
+
+ length = security_policydb_cksum(tmpbuf, tmpbuflen);
+ return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
+}
+
+static const struct file_operations sel_policycksum_ops = {
+ .read = sel_read_policycksum,
+ .llseek = generic_file_llseek,
+};
+
/* declaration for sel_write_load */
static int sel_make_bools(void);
static int sel_make_classes(void);
@@ -1825,6 +1843,8 @@ static int sel_fill_super(struct super_block *sb, void *data, int silent)
[SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
[SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
S_IWUGO},
+ [SEL_POLICYCKSUM] = {"policycksum", &sel_policycksum_ops,
+ S_IRUGO},
/* last one */ {""}
};
ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
--
1.8.3.1
