
Hi Philippe,
On Mon, 16 Dec 2024 at 07:48, Philippe REYNES < philippe.reynes@softathome.com> wrote:
Hi Raymond,
Le 13/12/2024 à 17:49, Raymond Mao a écrit :
*This Mail comes from Outside of SoftAtHome: *Do not answer, click links or open attachments unless you recognize the sender and know the content is safe. Hi Philippe,
On Thu, 12 Dec 2024 at 08:37, Philippe Reynes < philippe.reynes@softathome.com> wrote:
Adds the support of the hmac based on sha256. This implementation is based on rfc2104.
Signed-off-by: Philippe Reynes philippe.reynes@softathome.com
include/u-boot/sha256.h | 4 ++++ lib/sha256_common.c | 48 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+)
diff --git a/include/u-boot/sha256.h b/include/u-boot/sha256.h index 44a9b528b48..2f12275b703 100644 --- a/include/u-boot/sha256.h +++ b/include/u-boot/sha256.h @@ -45,4 +45,8 @@ void sha256_finish(sha256_context * ctx, uint8_t digest[SHA256_SUM_LEN]); void sha256_csum_wd(const unsigned char *input, unsigned int ilen, unsigned char *output, unsigned int chunk_sz);
+void sha256_hmac(const unsigned char *key, int keylen,
const unsigned char *input, unsigned int ilen,
unsigned char *output);
#endif /* _SHA256_H */ diff --git a/lib/sha256_common.c b/lib/sha256_common.c index 7041abd26d9..46262ea99a2 100644 --- a/lib/sha256_common.c +++ b/lib/sha256_common.c @@ -48,3 +48,51 @@ void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
sha256_finish(&ctx, output);
}
+void sha256_hmac(const unsigned char *key, int keylen,
const unsigned char *input, unsigned int ilen,
unsigned char *output)
+{
int i;
sha256_context ctx;
unsigned char keybuf[64];
unsigned char k_ipad[64];
unsigned char k_opad[64];
unsigned char tmpbuf[32];
int keybuf_len;
if (keylen > 64) {
sha256_starts(&ctx);
sha256_update(&ctx, key, keylen);
sha256_finish(&ctx, keybuf);
keybuf_len = 32;
} else {
memcpy(keybuf, key, keylen);
keybuf_len = keylen;
}
memset(k_ipad, 0x36, 64);
memset(k_opad, 0x5C, 64);
for (i = 0; i < keybuf_len; i++) {
k_ipad[i] ^= keybuf[i];
k_opad[i] ^= keybuf[i];
}
sha256_starts(&ctx);
sha256_update(&ctx, k_ipad, sizeof(k_ipad));
sha256_update(&ctx, input, ilen);
sha256_finish(&ctx, tmpbuf);
sha256_starts(&ctx);
sha256_update(&ctx, k_opad, sizeof(k_opad));
sha256_update(&ctx, tmpbuf, sizeof(tmpbuf));
sha256_finish(&ctx, output);
memset(k_ipad, 0, sizeof(k_ipad));
memset(k_opad, 0, sizeof(k_opad));
memset(tmpbuf, 0, sizeof(tmpbuf));
memset(keybuf, 0, sizeof(keybuf));
memset(&ctx, 0, sizeof(sha256_context));
+}
2.25.1
The sha256 hmac common implementation now sounds good.
Do you have a comparison of performance with the MbedTLS high-level API mbedtls_md_hmac()? I am wondering if it is worth using this API specially when MbedTLS is enabled, since it significantly simplifies the implementation.
I have done some test, and the legacy implementation is the fastest. To do my test, I have run 1 000 000 times the unit test for hmac. here the result: common + legacy => 7 seconds common + mbedtls => 17 seconds mbedtls => 17 seconds
I have kept common + mbedtls for the v5. But I may use a pure mbedtls if you prefer.
If my understanding is correct, "common + mbedtls => 17 seconds" means
mbedtls enabled and with your patch, while "mbedtls => 17 seconds" means using mbedtls_md_hmac(), right?
If this is the case, I would prefer to use mbedtls_md_hmac() since it brings more simplicity.
Regards, Raymond