summaryrefslogtreecommitdiff
path: root/include/crypto/chacha.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/crypto/chacha.h')
-rw-r--r--include/crypto/chacha.h7
1 files changed, 7 insertions, 0 deletions
diff --git a/include/crypto/chacha.h b/include/crypto/chacha.h
index b722a23e54bb..1fc70a69d550 100644
--- a/include/crypto/chacha.h
+++ b/include/crypto/chacha.h
@@ -5,6 +5,11 @@
* XChaCha extends ChaCha's nonce to 192 bits, while provably retaining ChaCha's
* security. Here they share the same key size, tfm context, and setkey
* function; only their IV size and encrypt/decrypt function differ.
+ *
+ * The ChaCha paper specifies 20, 12, and 8-round variants. In general, it is
+ * recommended to use the 20-round variant ChaCha20. However, the other
+ * variants can be needed in some performance-sensitive scenarios. The generic
+ * ChaCha code currently allows only the 20 and 12-round variants.
*/
#ifndef _CRYPTO_CHACHA_H
@@ -40,6 +45,8 @@ void crypto_chacha_init(u32 *state, struct chacha_ctx *ctx, u8 *iv);
int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key,
unsigned int keysize);
+int crypto_chacha12_setkey(struct crypto_skcipher *tfm, const u8 *key,
+ unsigned int keysize);
int crypto_chacha_crypt(struct skcipher_request *req);
int crypto_xchacha_crypt(struct skcipher_request *req);