fixes #3118 (Update toxcore to 0.2.18)

1 files changed, 44 insertions, 0 deletions

diff --git a/protocols/Tox/libtox/src/toxcore/timed_auth.c b/protocols/Tox/libtox/src/toxcore/timed_auth.c
new file mode 100644
index 0000000000..ebd5100286
--- /dev/null
+++ b/protocols/Tox/libtox/src/toxcore/timed_auth.c
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later
+ * Copyright © 2019-2021 The TokTok team.
+ */
+#include "timed_auth.h"
+
+#include <string.h>
+
+#include "ccompat.h"
+
+non_null(1,6) nullable(4)
+static void create_timed_auth_to_hash(const Mono_Time *mono_time, uint16_t timeout, bool previous, const uint8_t *data,
+                                      uint16_t length, uint8_t *to_hash)
+{
+    const uint64_t t = (mono_time_get(mono_time) / timeout) - (previous ? 1 : 0);
+    memcpy(to_hash, &t, sizeof(t));
+
+    if (data != nullptr) {
+        memcpy(to_hash + sizeof(t), data, length);
+    }
+}
+
+void generate_timed_auth(const Mono_Time *mono_time, uint16_t timeout, const uint8_t *key,
+                         const uint8_t *data, uint16_t length, uint8_t *timed_auth)
+{
+    VLA(uint8_t, to_hash, sizeof(uint64_t) + length);
+    create_timed_auth_to_hash(mono_time, timeout, false, data, length, to_hash);
+    crypto_hmac(timed_auth, key, to_hash, SIZEOF_VLA(to_hash));
+}
+
+bool check_timed_auth(const Mono_Time *mono_time, uint16_t timeout, const uint8_t *key, const uint8_t *data,
+                      uint16_t length, const uint8_t *timed_auth)
+{
+    VLA(uint8_t, to_hash, sizeof(uint64_t) + length);
+
+    for (uint8_t i = 0; i < 2; ++i) {
+        create_timed_auth_to_hash(mono_time, timeout, i != 0, data, length, to_hash);
+
+        if (crypto_hmac_verify(timed_auth, key, to_hash, SIZEOF_VLA(to_hash))) {
+            return true;
+        }
+    }
+
+    return false;
+}