From: Eric Biggers ebiggers@kernel.org
Now that there are easy-to-use HMAC-SHA256 library functions, use these in net/mptcp/crypto.c instead of open-coding the HMAC algorithm.
Remove the WARN_ON_ONCE() for messages longer than SHA256_DIGEST_SIZE. The new implementation handles all message lengths correctly.
The mptcp-crypto KUnit test still passes after this change.
Signed-off-by: Eric Biggers ebiggers@kernel.org Reviewed-by: Matthieu Baerts (NGI0) matttbe@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org --- net/mptcp/crypto.c | 35 ++--------------------------------- 1 file changed, 2 insertions(+), 33 deletions(-)
diff --git a/net/mptcp/crypto.c b/net/mptcp/crypto.c index b08ba959ac4fd485bb833043ff58d4c8bac8a37a..31948e18d97da7ee0ee2ae9e4f7c9ca0e3b330a7 100644 --- a/net/mptcp/crypto.c +++ b/net/mptcp/crypto.c @@ -22,7 +22,6 @@
#include <linux/kernel.h> #include <crypto/sha2.h> -#include <linux/unaligned.h>
#include "protocol.h"
@@ -43,39 +42,9 @@ void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn)
void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac) { - u8 input[SHA256_BLOCK_SIZE + SHA256_DIGEST_SIZE]; - u8 key1be[8]; - u8 key2be[8]; - int i; + __be64 key[2] = { cpu_to_be64(key1), cpu_to_be64(key2) };
- if (WARN_ON_ONCE(len > SHA256_DIGEST_SIZE)) - len = SHA256_DIGEST_SIZE; - - put_unaligned_be64(key1, key1be); - put_unaligned_be64(key2, key2be); - - /* Generate key xored with ipad */ - memset(input, 0x36, SHA256_BLOCK_SIZE); - for (i = 0; i < 8; i++) - input[i] ^= key1be[i]; - for (i = 0; i < 8; i++) - input[i + 8] ^= key2be[i]; - - memcpy(&input[SHA256_BLOCK_SIZE], msg, len); - - /* emit sha256(K1 || msg) on the second input block, so we can - * reuse 'input' for the last hashing - */ - sha256(input, SHA256_BLOCK_SIZE + len, &input[SHA256_BLOCK_SIZE]); - - /* Prepare second part of hmac */ - memset(input, 0x5C, SHA256_BLOCK_SIZE); - for (i = 0; i < 8; i++) - input[i] ^= key1be[i]; - for (i = 0; i < 8; i++) - input[i + 8] ^= key2be[i]; - - sha256(input, SHA256_BLOCK_SIZE + SHA256_DIGEST_SIZE, hmac); + hmac_sha256_usingrawkey((const u8 *)key, sizeof(key), msg, len, hmac); }
#if IS_MODULE(CONFIG_MPTCP_KUNIT_TEST)