On Tue, 1 Sep 2020 at 09:28, Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> wrote:
>
> Since commit b56f5cbc7e08ec7d31c42fc41e5247677f20b143 ("crypto:
> arm/aes-neonbs - resolve fallback cipher at runtime") the CBC
> encryption path in aes-neonbs is now identical to that obtained
> through the cbc template. This means that it can simply call
> the generic cbc template instead of doing its own thing.
>
> This patch removes the custom encryption path and simply invokes
> the generic cbc template.
>
> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
>
Aren't we ending up with a cbc(aes) implementation that allocates a
cbc(aes) implementation as a fallback?
> diff --git a/arch/arm/crypto/aes-neonbs-glue.c b/arch/arm/crypto/aes-neonbs-glue.c
> index e6fd32919c81..b324c5500846 100644
> --- a/arch/arm/crypto/aes-neonbs-glue.c
> +++ b/arch/arm/crypto/aes-neonbs-glue.c
> @@ -8,7 +8,6 @@
> #include <asm/neon.h>
> #include <asm/simd.h>
> #include <crypto/aes.h>
> -#include <crypto/cbc.h>
> #include <crypto/ctr.h>
> #include <crypto/internal/simd.h>
> #include <crypto/internal/skcipher.h>
> @@ -49,7 +48,7 @@ struct aesbs_ctx {
>
> struct aesbs_cbc_ctx {
> struct aesbs_ctx key;
> - struct crypto_cipher *enc_tfm;
> + struct crypto_skcipher *enc_tfm;
> };
>
> struct aesbs_xts_ctx {
> @@ -140,19 +139,23 @@ static int aesbs_cbc_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
> kernel_neon_end();
> memzero_explicit(&rk, sizeof(rk));
>
> - return crypto_cipher_setkey(ctx->enc_tfm, in_key, key_len);
> + return crypto_skcipher_setkey(ctx->enc_tfm, in_key, key_len);
> }
>
> -static void cbc_encrypt_one(struct crypto_skcipher *tfm, const u8 *src, u8 *dst)
> +static int cbc_encrypt(struct skcipher_request *req)
> {
> + struct skcipher_request *subreq = skcipher_request_ctx(req);
> + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
> struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>
> - crypto_cipher_encrypt_one(ctx->enc_tfm, dst, src);
> -}
> + skcipher_request_set_tfm(subreq, ctx->enc_tfm);
> + skcipher_request_set_callback(subreq,
> + skcipher_request_flags(req),
> + NULL, NULL);
> + skcipher_request_set_crypt(subreq, req->src, req->dst,
> + req->cryptlen, req->iv);
>
> -static int cbc_encrypt(struct skcipher_request *req)
> -{
> - return crypto_cbc_encrypt_walk(req, cbc_encrypt_one);
> + return crypto_skcipher_encrypt(subreq);
> }
>
> static int cbc_decrypt(struct skcipher_request *req)
> @@ -183,20 +186,27 @@ static int cbc_decrypt(struct skcipher_request *req)
> return err;
> }
>
> -static int cbc_init(struct crypto_tfm *tfm)
> +static int cbc_init(struct crypto_skcipher *tfm)
> {
> - struct aesbs_cbc_ctx *ctx = crypto_tfm_ctx(tfm);
> + struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
> + unsigned int reqsize;
> +
> + ctx->enc_tfm = crypto_alloc_skcipher("cbc(aes)", 0, 0);
> + if (IS_ERR(ctx->enc_tfm))
> + return PTR_ERR(ctx->enc_tfm);
>
> - ctx->enc_tfm = crypto_alloc_cipher("aes", 0, 0);
> + reqsize = sizeof(struct skcipher_request);
> + reqsize += crypto_skcipher_reqsize(ctx->enc_tfm);
> + crypto_skcipher_set_reqsize(tfm, reqsize);
>
> - return PTR_ERR_OR_ZERO(ctx->enc_tfm);
> + return 0;
> }
>
> -static void cbc_exit(struct crypto_tfm *tfm)
> +static void cbc_exit(struct crypto_skcipher *tfm)
> {
> - struct aesbs_cbc_ctx *ctx = crypto_tfm_ctx(tfm);
> + struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
>
> - crypto_free_cipher(ctx->enc_tfm);
> + crypto_free_skcipher(ctx->enc_tfm);
> }
>
> static int aesbs_ctr_setkey_sync(struct crypto_skcipher *tfm, const u8 *in_key,
> @@ -432,8 +442,6 @@ static struct skcipher_alg aes_algs[] = { {
> .base.cra_ctxsize = sizeof(struct aesbs_cbc_ctx),
> .base.cra_module = THIS_MODULE,
> .base.cra_flags = CRYPTO_ALG_INTERNAL,
> - .base.cra_init = cbc_init,
> - .base.cra_exit = cbc_exit,
>
> .min_keysize = AES_MIN_KEY_SIZE,
> .max_keysize = AES_MAX_KEY_SIZE,
> @@ -442,6 +450,8 @@ static struct skcipher_alg aes_algs[] = { {
> .setkey = aesbs_cbc_setkey,
> .encrypt = cbc_encrypt,
> .decrypt = cbc_decrypt,
> + .init = cbc_init,
> + .exit = cbc_exit,
> }, {
> .base.cra_name = "__ctr(aes)",
> .base.cra_driver_name = "__ctr-aes-neonbs",
> --
> Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
> Home Page: http://gondor.apana.org.au/~herbert/
> PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
