From c2646aeee94e71cb15c90a3147cf3b5b0ca158ca Mon Sep 17 00:00:00 2001

From: Daiki Ueno <ueno@gnu.org>

Date: Tue, 2 Jun 2020 20:53:11 +0200

Subject: [PATCH] stek: differentiate initial state from valid time window of

 TOTP

There was a confusion in the TOTP implementation in stek.c.  When the

mechanism is initialized at the first time, it records the timestamp

but doesn't initialize the key.  This removes the timestamp recording

at the initialization phase, so the key is properly set later.

Signed-off-by: Daiki Ueno <ueno@gnu.org>

---

 lib/stek.c                        | 17 +++++------------

 tests/resume-with-previous-stek.c |  4 ++--

 tests/tls13/prf-early.c           |  8 ++++----

 3 files changed, 11 insertions(+), 18 deletions(-)

diff --git a/lib/stek.c b/lib/stek.c

index 2f885cee3..5ab9e7d2d 100644

--- a/lib/stek.c

+++ b/lib/stek.c

@@ -323,20 +323,13 @@ int _gnutls_initialize_session_ticket_key_rotation(gnutls_session_t session, con

 	if (unlikely(session == NULL || key == NULL))

 		return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);

-	if (session->key.totp.last_result == 0) {

-		int64_t t;

-		memcpy(session->key.initial_stek, key->data, key->size);

-		t = totp_next(session);

-		if (t < 0)

-			return gnutls_assert_val(t);

+	if (unlikely(session->key.totp.last_result != 0))

+		return GNUTLS_E_INVALID_REQUEST;

-		session->key.totp.last_result = t;

-		session->key.totp.was_rotated = 0;

-

-		return GNUTLS_E_SUCCESS;

-	}

+	memcpy(session->key.initial_stek, key->data, key->size);

-	return GNUTLS_E_INVALID_REQUEST;

+	session->key.totp.was_rotated = 0;

+	return 0;

 }

 /*

diff --git a/tests/resume-with-previous-stek.c b/tests/resume-with-previous-stek.c

index f212b188b..05c1c9086 100644

--- a/tests/resume-with-previous-stek.c

+++ b/tests/resume-with-previous-stek.c

@@ -196,8 +196,8 @@ static void server(int fd, unsigned rounds, const char *prio)

 		serverx509cred = NULL;

 	}

-	if (num_stek_rotations != 2)

-		fail("STEK should be rotated exactly twice (%d)!\n", num_stek_rotations);

+	if (num_stek_rotations != 3)

+		fail("STEK should be rotated exactly three times (%d)!\n", num_stek_rotations);

 	if (serverx509cred)

 		gnutls_certificate_free_credentials(serverx509cred);

diff --git a/tests/tls13/prf-early.c b/tests/tls13/prf-early.c

index 414b1db5e..bc3196248 100644

--- a/tests/tls13/prf-early.c

+++ b/tests/tls13/prf-early.c

@@ -123,10 +123,10 @@ static void dump(const char *name, const uint8_t *data, unsigned data_size)

 	} \

 	}

-#define KEY_EXP_VALUE "\xc0\x1e\xc2\xa4\xb7\xb4\x04\xaa\x91\x5d\xaf\xe8\xf7\x4d\x19\xdf\xd0\xe6\x08\xd6\xb4\x3b\xcf\xca\xc9\x32\x75\x3b\xe3\x11\x19\xb1\xac\x68"

-#define HELLO_VALUE "\x77\xdb\x10\x0b\xe8\xd0\xb9\x38\xbc\x49\xe6\xbe\xf2\x47\x2a\xcc\x6b\xea\xce\x85\x04\xd3\x9e\xd8\x06\x16\xad\xff\xcd\xbf\x4b"

-#define CONTEXT_VALUE "\xf2\x17\x9f\xf2\x66\x56\x87\x66\xf9\x5c\x8a\xd7\x4e\x1d\x46\xee\x0e\x44\x41\x4c\xcd\xac\xcb\xc0\x31\x41\x2a\xb6\xd7\x01\x62"

-#define NULL_CONTEXT_VALUE "\xcd\x79\x07\x93\xeb\x96\x07\x3e\xec\x78\x90\x89\xf7\x16\x42\x6d\x27\x87\x56\x7c\x7b\x60\x2b\x20\x44\xd1\xea\x0c\x89\xfb\x8b"

+#define KEY_EXP_VALUE "\xc1\x6b\x6c\xb9\x88\x33\xd5\x28\x80\xec\x27\x87\xa2\x6f\x4b\xd0\x01\x5e\x7f\xca\xd7\xd4\x8a\x3f\xe2\x48\x92\xef\x02\x14\xfb\x81\x90\x04"

+#define HELLO_VALUE "\x2a\x73\xd9\x74\x04\x4e\x0a\x5f\x41\x8a\x09\xcb\x45\x33\x1a\xec\xd3\xfc\xdc\x1b\x2c\x67\x26\xe4\x9c\xfe\x1f\xa5\x74\xf1\x4f"

+#define CONTEXT_VALUE "\x87\xf6\x88\xe3\xd7\xf2\x05\xbc\xa4\x10\xa3\x48\x9f\xf5\xcf\x97\x06\x22\x4e\xfd\x18\x32\x52\x1d\xbd\x26\xf5\x5b\x21\x20\xec"

+#define NULL_CONTEXT_VALUE "\xf9\xca\xfe\x45\x44\x96\xdb\xc5\x41\x8f\x7e\x8e\xd7\xb0\x7d\x19\x45\xaf\x09\xbc\x1e\x82\x94\xac\x55\xe5\xb9\xb4\x3b\xe8\xc0"

 static int handshake_callback_called;

-- 

2.26.2