The plain CBC driver and the CTS one share some code that iterates over
a scatterwalk and invokes the CBC asm code to do the processing. The
upcoming ESSIV/CBC mode will clone that pattern for the third time, so
let's factor it out first.
Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org>
---
arch/arm64/crypto/aes-glue.c | 82 ++++++++++----------
1 file changed, 40 insertions(+), 42 deletions(-)
diff --git a/arch/arm64/crypto/aes-glue.c b/arch/arm64/crypto/aes-glue.c
index 55d6d4838708..23abf335f1ee 100644
--- a/arch/arm64/crypto/aes-glue.c
+++ b/arch/arm64/crypto/aes-glue.c
@@ -186,46 +186,64 @@ static int ecb_decrypt(struct skcipher_request *req)
return err;
}
-static int cbc_encrypt(struct skcipher_request *req)
+static int cbc_encrypt_walk(struct skcipher_request *req,
+ struct skcipher_walk *walk)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
- int err, rounds = 6 + ctx->key_length / 4;
- struct skcipher_walk walk;
+ int err = 0, rounds = 6 + ctx->key_length / 4;
unsigned int blocks;
- err = skcipher_walk_virt(&walk, req, false);
-
- while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
+ while ((blocks = (walk->nbytes / AES_BLOCK_SIZE))) {
kernel_neon_begin();
- aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
- ctx->key_enc, rounds, blocks, walk.iv);
+ aes_cbc_encrypt(walk->dst.virt.addr, walk->src.virt.addr,
+ ctx->key_enc, rounds, blocks, walk->iv);
kernel_neon_end();
- err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
+ err = skcipher_walk_done(walk, walk->nbytes % AES_BLOCK_SIZE);
}
return err;
}
-static int cbc_decrypt(struct skcipher_request *req)
+static int cbc_encrypt(struct skcipher_request *req)
{
- struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
- struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
- int err, rounds = 6 + ctx->key_length / 4;
struct skcipher_walk walk;
- unsigned int blocks;
+ int err;
err = skcipher_walk_virt(&walk, req, false);
+ if (err)
+ return err;
+ return cbc_encrypt_walk(req, &walk);
+}
- while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
+static int cbc_decrypt_walk(struct skcipher_request *req,
+ struct skcipher_walk *walk)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
+ int err = 0, rounds = 6 + ctx->key_length / 4;
+ unsigned int blocks;
+
+ while ((blocks = (walk->nbytes / AES_BLOCK_SIZE))) {
kernel_neon_begin();
- aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
- ctx->key_dec, rounds, blocks, walk.iv);
+ aes_cbc_decrypt(walk->dst.virt.addr, walk->src.virt.addr,
+ ctx->key_dec, rounds, blocks, walk->iv);
kernel_neon_end();
- err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
+ err = skcipher_walk_done(walk, walk->nbytes % AES_BLOCK_SIZE);
}
return err;
}
+static int cbc_decrypt(struct skcipher_request *req)
+{
+ struct skcipher_walk walk;
+ int err;
+
+ err = skcipher_walk_virt(&walk, req, false);
+ if (err)
+ return err;
+ return cbc_decrypt_walk(req, &walk);
+}
+
static int cts_cbc_init_tfm(struct crypto_skcipher *tfm)
{
crypto_skcipher_set_reqsize(tfm, sizeof(struct cts_cbc_req_ctx));
@@ -251,22 +269,12 @@ static int cts_cbc_encrypt(struct skcipher_request *req)
}
if (cbc_blocks > 0) {
- unsigned int blocks;
-
skcipher_request_set_crypt(&rctx->subreq, req->src, req->dst,
cbc_blocks * AES_BLOCK_SIZE,
req->iv);
- err = skcipher_walk_virt(&walk, &rctx->subreq, false);
-
- while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
- kernel_neon_begin();
- aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
- ctx->key_enc, rounds, blocks, walk.iv);
- kernel_neon_end();
- err = skcipher_walk_done(&walk,
- walk.nbytes % AES_BLOCK_SIZE);
- }
+ err = skcipher_walk_virt(&walk, &rctx->subreq, false) ?:
+ cbc_encrypt_walk(&rctx->subreq, &walk);
if (err)
return err;
@@ -316,22 +324,12 @@ static int cts_cbc_decrypt(struct skcipher_request *req)
}
if (cbc_blocks > 0) {
- unsigned int blocks;
-
skcipher_request_set_crypt(&rctx->subreq, req->src, req->dst,
cbc_blocks * AES_BLOCK_SIZE,
req->iv);
- err = skcipher_walk_virt(&walk, &rctx->subreq, false);
-
- while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
- kernel_neon_begin();
- aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
- ctx->key_dec, rounds, blocks, walk.iv);
- kernel_neon_end();
- err = skcipher_walk_done(&walk,
- walk.nbytes % AES_BLOCK_SIZE);
- }
+ err = skcipher_walk_virt(&walk, &rctx->subreq, false) ?:
+ cbc_decrypt_walk(&rctx->subreq, &walk);
if (err)
return err;
--
2.17.1
