2019-07-25 14:22:19

by Iuliana Prodan

Subject: [PATCH 0/2] crypto: validate inputs for gcm and aes

Added inline helper functions to check authsize and assoclen for
gcm and rfc4106.
Added, also, inline helper function to check key length for AES algorithms.
These are used in the generic implementation of gcm/rfc4106 and aes/aes_ti.

Iuliana Prodan (2):
crypto: gcm - helper functions for assoclen/authsize check
crypto: aes - helper function to validate key length for AES
algorithms

crypto/aes_generic.c | 7 ++++---
crypto/aes_ti.c | 8 ++++----
crypto/gcm.c | 41 +++++++++++++++-------------------------
include/crypto/aes.h | 17 +++++++++++++++++
include/crypto/gcm.h | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 93 insertions(+), 33 deletions(-)

--
2.1.0

2019-07-25 14:23:37

by Iuliana Prodan

Subject: [PATCH 2/2] crypto: aes - helper function to validate key length for AES algorithms

Add inline helper function to check key length for AES algorithms.
The key can be 128, 192 or 256 bits size.
This function is used in the generic aes and aes_ti implementations.

Signed-off-by: Iuliana Prodan <[email protected]>
---
crypto/aes_generic.c | 7 ++++---
crypto/aes_ti.c | 8 ++++----
include/crypto/aes.h | 17 +++++++++++++++++
3 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/crypto/aes_generic.c b/crypto/aes_generic.c
index f217568..f5b7cf6 100644
--- a/crypto/aes_generic.c
+++ b/crypto/aes_generic.c
@@ -1219,10 +1219,11 @@ int crypto_aes_expand_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
unsigned int key_len)
{
u32 i, t, u, v, w, j;
+ int err;

- if (key_len != AES_KEYSIZE_128 && key_len != AES_KEYSIZE_192 &&
- key_len != AES_KEYSIZE_256)
- return -EINVAL;
+ err = check_aes_keylen(key_len);
+ if (err)
+ return err;

ctx->key_length = key_len;

diff --git a/crypto/aes_ti.c b/crypto/aes_ti.c
index 1ff9785b..786311c 100644
--- a/crypto/aes_ti.c
+++ b/crypto/aes_ti.c
@@ -172,11 +172,11 @@ static int aesti_expand_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
{
u32 kwords = key_len / sizeof(u32);
u32 rc, i, j;
+ int err;

- if (key_len != AES_KEYSIZE_128 &&
- key_len != AES_KEYSIZE_192 &&
- key_len != AES_KEYSIZE_256)
- return -EINVAL;
+ err = check_aes_keylen(key_len);
+ if (err)
+ return err;

ctx->key_length = key_len;

diff --git a/include/crypto/aes.h b/include/crypto/aes.h
index 0fdb542..c3a92ca 100644
--- a/include/crypto/aes.h
+++ b/include/crypto/aes.h
@@ -33,6 +33,23 @@ extern const u32 crypto_fl_tab[4][256] ____cacheline_aligned;
extern const u32 crypto_it_tab[4][256] ____cacheline_aligned;
extern const u32 crypto_il_tab[4][256] ____cacheline_aligned;

+/*
+ * validate key length for AES algorithms
+ */
+static inline int check_aes_keylen(unsigned int keylen)
+{
+ switch (keylen) {
+ case AES_KEYSIZE_128:
+ case AES_KEYSIZE_192:
+ case AES_KEYSIZE_256:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len);
int crypto_aes_expand_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
--
2.1.0

2019-07-26 13:51:16

by Horia Geanta

Subject: Re: [PATCH 2/2] crypto: aes - helper function to validate key length for AES algorithms

On 7/25/2019 4:47 PM, Iuliana Prodan wrote:
> Add inline helper function to check key length for AES algorithms.
> The key can be 128, 192 or 256 bits size.
> This function is used in the generic aes and aes_ti implementations.
>
Looks good.
Will need to respin it, since aes has just been refactored and moved in lib/crypto/.

Horia