From 7d52f2a0d939c610e18f7cd2b7d3a6361f3d4a98 Mon Sep 17 00:00:00 2001 From: Dave Rodgman Date: Tue, 12 Sep 2023 16:29:39 +0100 Subject: [PATCH] Improve use of ct interface in mbedtls_ssl_decrypt_buf Signed-off-by: Dave Rodgman --- library/ssl_msg.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/library/ssl_msg.c b/library/ssl_msg.c index 85632a1c31..47a206dd44 100644 --- a/library/ssl_msg.c +++ b/library/ssl_msg.c @@ -1504,7 +1504,8 @@ int mbedtls_ssl_decrypt_buf(mbedtls_ssl_context const *ssl, int auth_done = 0; #if defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC) - size_t padlen = 0, correct = 1; + size_t padlen = 0; + mbedtls_ct_condition_t correct = MBEDTLS_CT_TRUE; #endif unsigned char *data; /* For an explanation of the additional data length see @@ -1921,7 +1922,7 @@ hmac_failed_etm_enabled: const mbedtls_ct_condition_t ge = mbedtls_ct_uint_ge( rec->data_len, padlen + 1); - correct = mbedtls_ct_size_if_else_0(ge, correct); + correct = mbedtls_ct_bool_and(ge, correct); padlen = mbedtls_ct_size_if_else_0(ge, padlen); } else { #if defined(MBEDTLS_SSL_DEBUG_ALL) @@ -1937,7 +1938,7 @@ hmac_failed_etm_enabled: const mbedtls_ct_condition_t ge = mbedtls_ct_uint_ge( rec->data_len, transform->maclen + padlen + 1); - correct = mbedtls_ct_size_if_else_0(ge, correct); + correct = mbedtls_ct_bool_and(ge, correct); padlen = mbedtls_ct_size_if_else_0(ge, padlen); } @@ -1973,14 +1974,14 @@ hmac_failed_etm_enabled: increment = mbedtls_ct_size_if_else_0(b, increment); pad_count += increment; } - correct = mbedtls_ct_size_if_else_0(mbedtls_ct_uint_eq(pad_count, padlen), correct); + correct = mbedtls_ct_bool_and(mbedtls_ct_uint_eq(pad_count, padlen), correct); #if defined(MBEDTLS_SSL_DEBUG_ALL) - if (padlen > 0 && correct == 0) { + if (padlen > 0 && correct == MBEDTLS_CT_FALSE) { MBEDTLS_SSL_DEBUG_MSG(1, ("bad padding byte detected")); } #endif - padlen = mbedtls_ct_size_if_else_0(mbedtls_ct_bool(correct), padlen); + padlen = mbedtls_ct_size_if_else_0(correct, padlen); #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ @@ -2075,7 +2076,7 @@ hmac_failed_etm_enabled: #if defined(MBEDTLS_SSL_DEBUG_ALL) MBEDTLS_SSL_DEBUG_MSG(1, ("message mac does not match")); #endif - correct = 0; + correct = MBEDTLS_CT_FALSE; } auth_done++; @@ -2090,7 +2091,7 @@ hmac_failed_etm_disabled: /* * Finally check the correct flag */ - if (correct == 0) { + if (correct == MBEDTLS_CT_FALSE) { return MBEDTLS_ERR_SSL_INVALID_MAC; } #endif /* MBEDTLS_SSL_SOME_SUITES_USE_MAC */