Re: [PATCH 2/2] SELinux: Measure state and hash of policy using IMA

From: Lakshmi Ramasubramanian
Date: Thu Aug 13 2020 - 13:52:10 EST


On 8/13/20 10:42 AM, Stephen Smalley wrote:

diff --git a/security/selinux/measure.c b/security/selinux/measure.c
new file mode 100644
index 000000000000..f21b7de4e2ae
--- /dev/null
+++ b/security/selinux/measure.c
@@ -0,0 +1,204 @@
+static int selinux_hash_buffer(void *buf, size_t buf_len,
+                   void **buf_hash, int *buf_hash_len)
+{
+    struct crypto_shash *tfm;
+    struct shash_desc *desc = NULL;
+    void *digest = NULL;
+    int desc_size;
+    int digest_size;
+    int ret = 0;
+
+    tfm = crypto_alloc_shash("sha256", 0, 0);
+    if (IS_ERR(tfm))
+        return PTR_ERR(tfm);
Can we make the algorithm selectable via kernel parameter and/or writing to a new selinuxfs node?

I can add a kernel parameter to select this hash algorithm.

-lakshmi