As architecture specific drivers need a software fallback, export a
ChaCha20 en-/decryption function together with some helpers in a header
file.
Signed-off-by: Martin Willi <martin@xxxxxxxxxxxxxx>
---
crypto/chacha20_generic.c | 28 ++++++++++++----------------
crypto/chacha20poly1305.c | 3 +--
include/crypto/chacha20.h | 25 +++++++++++++++++++++++++
3 files changed, 38 insertions(+), 18 deletions(-)
create mode 100644 include/crypto/chacha20.h
diff --git a/crypto/chacha20_generic.c b/crypto/chacha20_generic.c
index fa42e70..da9c899 100644
--- a/crypto/chacha20_generic.c
+++ b/crypto/chacha20_generic.c
@@ -13,14 +13,7 @@
#include <linux/crypto.h>
#include <linux/kernel.h>
#include <linux/module.h>
-
-#define CHACHA20_NONCE_SIZE 16
-#define CHACHA20_KEY_SIZE 32
-#define CHACHA20_BLOCK_SIZE 64
-
-struct chacha20_ctx {
- u32 key[8];
-};
+#include <crypto/chacha20.h>
static inline u32 rotl32(u32 v, u8 n)
{
@@ -108,7 +101,7 @@ static void chacha20_docrypt(u32 *state, u8 *dst, const u8 *src,
}
}
-static void chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv)
+void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv)
{
static const char constant[16] = "expand 32-byte k";
@@ -129,8 +122,9 @@ static void chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv)
state[14] = le32_to_cpuvp(iv + 8);
state[15] = le32_to_cpuvp(iv + 12);
}
+EXPORT_SYMBOL_GPL(crypto_chacha20_init);
-static int chacha20_setkey(struct crypto_tfm *tfm, const u8 *key,
+int crypto_chacha20_setkey(struct crypto_tfm *tfm, const u8 *key,
unsigned int keysize)
{
struct chacha20_ctx *ctx = crypto_tfm_ctx(tfm);
@@ -144,8 +138,9 @@ static int chacha20_setkey(struct crypto_tfm *tfm, const u8 *key,
return 0;
}
+EXPORT_SYMBOL_GPL(crypto_chacha20_setkey);
-static int chacha20_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
+int crypto_chacha20_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct blkcipher_walk walk;
@@ -155,7 +150,7 @@ static int chacha20_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt_block(desc, &walk, CHACHA20_BLOCK_SIZE);
- chacha20_init(state, crypto_blkcipher_ctx(desc->tfm), walk.iv);
+ crypto_chacha20_init(state, crypto_blkcipher_ctx(desc->tfm), walk.iv);
while (walk.nbytes >= CHACHA20_BLOCK_SIZE) {
chacha20_docrypt(state, walk.dst.virt.addr, walk.src.virt.addr,
@@ -172,6 +167,7 @@ static int chacha20_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
return err;
}
+EXPORT_SYMBOL_GPL(crypto_chacha20_crypt);
static struct crypto_alg alg = {
.cra_name = "chacha20",
@@ -187,11 +183,11 @@ static struct crypto_alg alg = {
.blkcipher = {
.min_keysize = CHACHA20_KEY_SIZE,
.max_keysize = CHACHA20_KEY_SIZE,
- .ivsize = CHACHA20_NONCE_SIZE,
+ .ivsize = CHACHA20_IV_SIZE,
.geniv = "seqiv",
- .setkey = chacha20_setkey,
- .encrypt = chacha20_crypt,
- .decrypt = chacha20_crypt,
+ .setkey = crypto_chacha20_setkey,
+ .encrypt = crypto_chacha20_crypt,
+ .decrypt = crypto_chacha20_crypt,
},
},
};
diff --git a/crypto/chacha20poly1305.c b/crypto/chacha20poly1305.c
index 8626093..410554d 100644
--- a/crypto/chacha20poly1305.c
+++ b/crypto/chacha20poly1305.c
@@ -13,6 +13,7 @@
#include <crypto/internal/hash.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
+#include <crypto/chacha20.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
@@ -23,8 +24,6 @@
#define POLY1305_BLOCK_SIZE 16
#define POLY1305_DIGEST_SIZE 16
#define POLY1305_KEY_SIZE 32
-#define CHACHA20_KEY_SIZE 32
-#define CHACHA20_IV_SIZE 16
#define CHACHAPOLY_IV_SIZE 12
struct chachapoly_instance_ctx {
diff --git a/include/crypto/chacha20.h b/include/crypto/chacha20.h
new file mode 100644
index 0000000..274bbae
--- /dev/null
+++ b/include/crypto/chacha20.h
@@ -0,0 +1,25 @@
+/*
+ * Common values for the ChaCha20 algorithm
+ */
+
+#ifndef _CRYPTO_CHACHA20_H
+#define _CRYPTO_CHACHA20_H
+
+#include <linux/types.h>
+#include <linux/crypto.h>
+
+#define CHACHA20_IV_SIZE 16
+#define CHACHA20_KEY_SIZE 32
+#define CHACHA20_BLOCK_SIZE 64
+
+struct chacha20_ctx {
+ u32 key[8];
+};
+
+void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv);
+int crypto_chacha20_setkey(struct crypto_tfm *tfm, const u8 *key,
+ unsigned int keysize);
+int crypto_chacha20_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes);
+
+#endif
--
1.9.1
--
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