crypto: chacha20 - Add a generic ChaCha20 stream cipher implementation
ChaCha20 is a high speed 256-bit key size stream cipher algorithm designed by
Daniel J. Bernstein. It is further specified in RFC7539 for use in IETF
protocols as a building block for the ChaCha20-Poly1305 AEAD.
This is a portable C implementation without any architecture specific
optimizations. It uses a 16-byte IV, which includes the 12-byte ChaCha20 nonce
prepended by the initial block counter. Some algorithms require an explicit
counter value, for example the mentioned AEAD construction.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/Kconfig b/crypto/Kconfig
index af011a9..bf657be 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1156,6 +1156,19 @@
The Salsa20 stream cipher algorithm is designed by Daniel J.
Bernstein <djb@cr.yp.to>. See <http://cr.yp.to/snuffle.html>
+config CRYPTO_CHACHA20
+ tristate "ChaCha20 cipher algorithm"
+ select CRYPTO_BLKCIPHER
+ help
+ ChaCha20 cipher algorithm, RFC7539.
+
+ ChaCha20 is a 256-bit high-speed stream cipher designed by Daniel J.
+ Bernstein and further specified in RFC7539 for use in IETF protocols.
+ This is the portable C implementation of ChaCha20.
+
+ See also:
+ <http://cr.yp.to/chacha/chacha-20080128.pdf>
+
config CRYPTO_SEED
tristate "SEED cipher algorithm"
select CRYPTO_ALGAPI
