From: Ard Biesheuvel ard.biesheuvel@linaro.org
commit 504582e8e40b90b8f8c58783e2d1e4f6a2b71a3a upstream.
Commit 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") updated the generic CBC template wrapper from a blkcipher to a skcipher algo, to get away from the deprecated blkcipher interface. However, as a side effect, drivers that instantiate CBC transforms using the blkcipher as a fallback no longer work, since skciphers can wrap blkciphers but not the other way around. This broke the geode-aes driver.
So let's fix it by moving to the sync skcipher interface when allocating the fallback. At the same time, align with the generic API for ECB and CBC by rejecting inputs that are not a multiple of the AES block size.
Fixes: 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") Cc: stable@vger.kernel.org # v4.20+ ONLY Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org Signed-off-by: Florian Bezdeka florian@bezdeka.de Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/crypto/geode-aes.c | 57 ++++++++++++++++++++++++++------------------- drivers/crypto/geode-aes.h | 2 - 2 files changed, 34 insertions(+), 25 deletions(-)
--- a/drivers/crypto/geode-aes.c +++ b/drivers/crypto/geode-aes.c @@ -10,6 +10,7 @@ #include <linux/spinlock.h> #include <crypto/algapi.h> #include <crypto/aes.h> +#include <crypto/skcipher.h>
#include <linux/io.h> #include <linux/delay.h> @@ -166,13 +167,15 @@ static int geode_setkey_blk(struct crypt /* * The requested key size is not supported by HW, do a fallback */ - op->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; - op->fallback.blk->base.crt_flags |= (tfm->crt_flags & CRYPTO_TFM_REQ_MASK); + crypto_sync_skcipher_clear_flags(op->fallback.blk, CRYPTO_TFM_REQ_MASK); + crypto_sync_skcipher_set_flags(op->fallback.blk, + tfm->crt_flags & CRYPTO_TFM_REQ_MASK);
- ret = crypto_blkcipher_setkey(op->fallback.blk, key, len); + ret = crypto_sync_skcipher_setkey(op->fallback.blk, key, len); if (ret) { tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; - tfm->crt_flags |= (op->fallback.blk->base.crt_flags & CRYPTO_TFM_RES_MASK); + tfm->crt_flags |= crypto_sync_skcipher_get_flags(op->fallback.blk) & + CRYPTO_TFM_RES_MASK; } return ret; } @@ -181,33 +184,28 @@ static int fallback_blk_dec(struct blkci struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { - unsigned int ret; - struct crypto_blkcipher *tfm; struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); + SYNC_SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);
- tfm = desc->tfm; - desc->tfm = op->fallback.blk; - - ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes); + skcipher_request_set_sync_tfm(req, op->fallback.blk); + skcipher_request_set_callback(req, 0, NULL, NULL); + skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
- desc->tfm = tfm; - return ret; + return crypto_skcipher_decrypt(req); } + static int fallback_blk_enc(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { - unsigned int ret; - struct crypto_blkcipher *tfm; struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); + SYNC_SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);
- tfm = desc->tfm; - desc->tfm = op->fallback.blk; - - ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes); + skcipher_request_set_sync_tfm(req, op->fallback.blk); + skcipher_request_set_callback(req, 0, NULL, NULL); + skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
- desc->tfm = tfm; - return ret; + return crypto_skcipher_encrypt(req); }
static void @@ -307,6 +305,9 @@ geode_cbc_decrypt(struct blkcipher_desc struct blkcipher_walk walk; int err, ret;
+ if (nbytes % AES_BLOCK_SIZE) + return -EINVAL; + if (unlikely(op->keylen != AES_KEYSIZE_128)) return fallback_blk_dec(desc, dst, src, nbytes);
@@ -339,6 +340,9 @@ geode_cbc_encrypt(struct blkcipher_desc struct blkcipher_walk walk; int err, ret;
+ if (nbytes % AES_BLOCK_SIZE) + return -EINVAL; + if (unlikely(op->keylen != AES_KEYSIZE_128)) return fallback_blk_enc(desc, dst, src, nbytes);
@@ -366,9 +370,8 @@ static int fallback_init_blk(struct cryp const char *name = crypto_tfm_alg_name(tfm); struct geode_aes_op *op = crypto_tfm_ctx(tfm);
- op->fallback.blk = crypto_alloc_blkcipher(name, 0, - CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); - + op->fallback.blk = crypto_alloc_sync_skcipher(name, 0, + CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(op->fallback.blk)) { printk(KERN_ERR "Error allocating fallback algo %s\n", name); return PTR_ERR(op->fallback.blk); @@ -381,7 +384,7 @@ static void fallback_exit_blk(struct cry { struct geode_aes_op *op = crypto_tfm_ctx(tfm);
- crypto_free_blkcipher(op->fallback.blk); + crypto_free_sync_skcipher(op->fallback.blk); op->fallback.blk = NULL; }
@@ -420,6 +423,9 @@ geode_ecb_decrypt(struct blkcipher_desc struct blkcipher_walk walk; int err, ret;
+ if (nbytes % AES_BLOCK_SIZE) + return -EINVAL; + if (unlikely(op->keylen != AES_KEYSIZE_128)) return fallback_blk_dec(desc, dst, src, nbytes);
@@ -450,6 +456,9 @@ geode_ecb_encrypt(struct blkcipher_desc struct blkcipher_walk walk; int err, ret;
+ if (nbytes % AES_BLOCK_SIZE) + return -EINVAL; + if (unlikely(op->keylen != AES_KEYSIZE_128)) return fallback_blk_enc(desc, dst, src, nbytes);
--- a/drivers/crypto/geode-aes.h +++ b/drivers/crypto/geode-aes.h @@ -60,7 +60,7 @@ struct geode_aes_op { u8 *iv;
union { - struct crypto_blkcipher *blk; + struct crypto_sync_skcipher *blk; struct crypto_cipher *cip; } fallback; u32 keylen;