KEYS: Add placeholder for KDF usage with DH
The values computed during Diffie-Hellman key exchange are often used
in combination with key derivation functions to create cryptographic
keys. Add a placeholder for a later implementation to configure a
key derivation function that will transform the Diffie-Hellman
result returned by the KEYCTL_DH_COMPUTE command.
[This patch was stripped down from a patch produced by Mat Martineau that
had a bug in the compat code - so for the moment Stephan's patch simply
requires that the placeholder argument must be NULL]
Original-signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 8ec7a52..a705a7d 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -260,10 +260,11 @@
#ifdef CONFIG_KEY_DH_OPERATIONS
extern long keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
- size_t);
+ size_t, void __user *);
#else
static inline long keyctl_dh_compute(struct keyctl_dh_params __user *params,
- char __user *buffer, size_t buflen)
+ char __user *buffer, size_t buflen,
+ void __user *reserved)
{
return -EOPNOTSUPP;
}