path: root/Documentation/security/keys.txt
diff options
authorStephan Mueller <smueller@chronox.de>2016-05-26 23:38:12 +0200
committerJames Morris <james.l.morris@oracle.com>2016-06-03 16:14:34 +1000
commit4693fc734d675c5518ea9bd4c9623db45bc37402 (patch)
tree54dcf2388f5868c5d5a8ab4faf3b64a8e2fa4f79 /Documentation/security/keys.txt
parentMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm (diff)
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>
Diffstat (limited to 'Documentation/security/keys.txt')
1 files changed, 4 insertions, 1 deletions
diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt
index 20d05719bceb..3849814bfe6d 100644
--- a/Documentation/security/keys.txt
+++ b/Documentation/security/keys.txt
@@ -826,7 +826,8 @@ The keyctl syscall functions are:
(*) Compute a Diffie-Hellman shared secret or public key
long keyctl(KEYCTL_DH_COMPUTE, struct keyctl_dh_params *params,
- char *buffer, size_t buflen);
+ char *buffer, size_t buflen,
+ void *reserved);
The params struct contains serial numbers for three keys:
@@ -843,6 +844,8 @@ The keyctl syscall functions are:
public key. If the base is the remote public key, the result is
the shared secret.
+ The reserved argument must be set to NULL.
The buffer length must be at least the length of the prime, or zero.
If the buffer length is nonzero, the length of the result is