[PATCH v4 2/2] selinux: expose policy brief via selinuxfs

From: Sebastien Buisson
Date: Mon May 15 2017 - 14:23:11 EST


Expose policy brief via selinuxfs.

Signed-off-by: Sebastien Buisson <sbuisson@xxxxxxx>
---
security/selinux/selinuxfs.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index e8fe914..2561f96 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -99,6 +99,7 @@ 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_POLICYBRIEF,/* return policy summary */
SEL_INO_NEXT, /* The next inode number to use */
};

@@ -314,6 +315,29 @@ static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
.llseek = generic_file_llseek,
};

+static ssize_t sel_read_policybrief(struct file *filp, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ char *tmpbuf;
+ size_t len;
+ ssize_t rc;
+
+ rc = security_policydb_brief(&tmpbuf, &len, true);
+ if (rc)
+ return rc;
+
+ rc = simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
+
+ kfree(tmpbuf);
+
+ return rc;
+}
+
+static const struct file_operations sel_policybrief_ops = {
+ .read = sel_read_policybrief,
+ .llseek = generic_file_llseek,
+};
+
/* declaration for sel_write_load */
static int sel_make_bools(void);
static int sel_make_classes(void);
@@ -1827,6 +1851,8 @@ 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_POLICYBRIEF] = {"policybrief", &sel_policybrief_ops,
+ S_IRUGO},
/* last one */ {""}
};
ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
--
1.8.3.1