On Mon, Oct 14, 2019 at 10:45:22AM +0200, Ard Biesheuvel wrote:
> Hi Eric,
>
> On Sat, 12 Oct 2019 at 04:32, Eric Biggers <ebiggers@xxxxxxxxxx> wrote:
> >
> > From: Eric Biggers <ebiggers@xxxxxxxxxx>
> >
> > Convert the glue code for the PowerPC SPE implementations of AES-ECB,
> > AES-CBC, AES-CTR, and AES-XTS from the deprecated "blkcipher" API to the
> > "skcipher" API.
> >
> > Tested with:
> >
> > export ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
> > make mpc85xx_defconfig
> > cat >> .config << EOF
> > # CONFIG_MODULES is not set
> > # CONFIG_CRYPTO_MANAGER_DISABLE_TESTS is not set
> > CONFIG_DEBUG_KERNEL=y
> > CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y
> > CONFIG_CRYPTO_AES=y
> > CONFIG_CRYPTO_CBC=y
> > CONFIG_CRYPTO_CTR=y
> > CONFIG_CRYPTO_ECB=y
> > CONFIG_CRYPTO_XTS=y
> > CONFIG_CRYPTO_AES_PPC_SPE=y
> > EOF
> > make olddefconfig
> > make -j32
> > qemu-system-ppc -M mpc8544ds -cpu e500 -nographic \
> > -kernel arch/powerpc/boot/zImage \
> > -append cryptomgr.fuzz_iterations=1000
> >
> > Note that xts-ppc-spe still fails the comparison tests due to the lack
> > of ciphertext stealing support. This is not addressed by this patch.
> >
> > Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
> > ---
> > arch/powerpc/crypto/aes-spe-glue.c | 416 +++++++++++++----------------
> > crypto/Kconfig | 1 +
> > 2 files changed, 186 insertions(+), 231 deletions(-)
> >
> > diff --git a/arch/powerpc/crypto/aes-spe-glue.c b/arch/powerpc/crypto/aes-spe-glue.c
> > index 3a4ca7d32477..374e3e51e998 100644
> > --- a/arch/powerpc/crypto/aes-spe-glue.c
> > +++ b/arch/powerpc/crypto/aes-spe-glue.c
> > @@ -17,6 +17,7 @@
> > #include <asm/byteorder.h>
> > #include <asm/switch_to.h>
> > #include <crypto/algapi.h>
> > +#include <crypto/internal/skcipher.h>
> > #include <crypto/xts.h>
> >
> > /*
> > @@ -86,17 +87,13 @@ static void spe_end(void)
> > preempt_enable();
> > }
> >
> > -static int ppc_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
> > - unsigned int key_len)
> > +static int expand_key(struct ppc_aes_ctx *ctx,
> > + const u8 *in_key, unsigned int key_len)
> > {
> > - struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
> > -
> > if (key_len != AES_KEYSIZE_128 &&
> > key_len != AES_KEYSIZE_192 &&
> > - key_len != AES_KEYSIZE_256) {
> > - tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
> > + key_len != AES_KEYSIZE_256)
> > return -EINVAL;
> > - }
> >
> > switch (key_len) {
> > case AES_KEYSIZE_128:
> > @@ -114,17 +111,40 @@ static int ppc_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
> > }
> >
> > ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);
> > + return 0;
> > +}
> >
> > +static int ppc_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
> > + unsigned int key_len)
> > +{
> > + struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
> > +
> > + if (expand_key(ctx, in_key, key_len) != 0) {
> > + tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
> > + return -EINVAL;
> > + }
> > + return 0;
> > +}
> > +
> > +static int ppc_aes_setkey_skcipher(struct crypto_skcipher *tfm,
> > + const u8 *in_key, unsigned int key_len)
> > +{
> > + struct ppc_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
> > +
> > + if (expand_key(ctx, in_key, key_len) != 0) {
> > + crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
> > + return -EINVAL;
> > + }
> > return 0;
> > }
> >
> > -static int ppc_xts_setkey(struct crypto_tfm *tfm, const u8 *in_key,
> > +static int ppc_xts_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
> > unsigned int key_len)
> > {
> > - struct ppc_xts_ctx *ctx = crypto_tfm_ctx(tfm);
> > + struct ppc_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
> > int err;
> >
> > - err = xts_check_key(tfm, in_key, key_len);
> > + err = xts_verify_key(tfm, in_key, key_len);
> > if (err)
> > return err;
> >
> > @@ -133,7 +153,7 @@ static int ppc_xts_setkey(struct crypto_tfm *tfm, const u8 *in_key,
> > if (key_len != AES_KEYSIZE_128 &&
> > key_len != AES_KEYSIZE_192 &&
> > key_len != AES_KEYSIZE_256) {
> > - tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
> > + crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
> > return -EINVAL;
> > }
> >
> > @@ -178,208 +198,154 @@ static void ppc_aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
> > spe_end();
> > }
> >
> > -static int ppc_ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
> > - struct scatterlist *src, unsigned int nbytes)
> > +static int ppc_ecb_crypt(struct skcipher_request *req, bool enc)
> > {
> > - struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
> > - struct blkcipher_walk walk;
> > - unsigned int ubytes;
> > + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
> > + struct ppc_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
> > + struct skcipher_walk walk;
> > + unsigned int nbytes;
> > int err;
> >
> > - desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
> > - blkcipher_walk_init(&walk, dst, src, nbytes);
> > - err = blkcipher_walk_virt(desc, &walk);
> > + err = skcipher_walk_virt(&walk, req, false);
> >
>
> Shouldn't atomic be set to 'true' here to retain the non-sleeping behavior?
This was intentional since the non-sleeping behavior is unnecessary, as the call
to skcipher_walk_done() is not within the spe_begin() / spe_end() section.
I can split this into a separate patch if it would make it clearer, though.
>
> > - while ((nbytes = walk.nbytes)) {
> > - ubytes = nbytes > MAX_BYTES ?
> > - nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
> > - nbytes -= ubytes;
> > + while ((nbytes = walk.nbytes) != 0) {
> > + nbytes = min_t(unsigned int, nbytes, MAX_BYTES);
> > + nbytes = round_down(nbytes, AES_BLOCK_SIZE);
> >
> > spe_begin();
> > - ppc_encrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
> > - ctx->key_enc, ctx->rounds, nbytes);
> > + if (enc)
> > + ppc_encrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
> > + ctx->key_enc, ctx->rounds, nbytes);
> > + else
> > + ppc_decrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
> > + ctx->key_dec, ctx->rounds, nbytes);
> > spe_end();
> >
> > - err = blkcipher_walk_done(desc, &walk, ubytes);
> > + err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
> > }
> >
> > return err;
> > }
