[CRYPTO] xts: XTS blockcipher mode implementation without partial blocks

XTS currently considered to be the successor of the LRW mode by the IEEE1619
workgroup. LRW was discarded, because it was not secure if the encyption key
itself is encrypted with LRW.

XTS does not have this problem. The implementation is pretty straightforward,
a new function was added to gf128mul to handle GF(128) elements in ble format.
Four testvectors from the specification
	http://grouper.ieee.org/groups/1619/email/pdf00086.pdf
were added, and they verify on my system.

Signed-off-by: Rik Snel <rsnel@cube.dyndns.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/crypto/gf128mul.h b/include/crypto/gf128mul.h
index 4fd315202442..4086b8ebfafe 100644
--- a/include/crypto/gf128mul.h
+++ b/include/crypto/gf128mul.h
@@ -161,6 +161,8 @@ void gf128mul_lle(be128 *a, const be128 *b);
 
 void gf128mul_bbe(be128 *a, const be128 *b);
 
+/* multiply by x in ble format, needed by XTS */
+void gf128mul_x_ble(be128 *a, const be128 *b);
 
 /* 4k table optimization */