* When the rekey started. One minute after this the new key will be used.
*/
struct GNUNET_TIME_Absolute rekey_start_time;
+
+ /**
+ * Task for delayed destruction of the Key eXchange context, to allow delayed
+ * messages with the old key to be decrypted successfully.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier finish_task;
};
/**
size_t out_size;
LOG (GNUNET_ERROR_TYPE_DEBUG, " t_encrypt start\n");
- if (NULL != t->kx_ctx)
+ if (NULL != t->kx_ctx && GNUNET_SCHEDULER_NO_TASK == t->kx_ctx->finish_task)
{
struct GNUNET_TIME_Relative age;
t_decrypt (struct CadetTunnel *t, void *dst, const void *src,
size_t size, uint32_t iv)
{
- struct GNUNET_CRYPTO_SymmetricInitializationVector siv;
struct GNUNET_CRYPTO_SymmetricSessionKey *key;
size_t out_size;
return decrypted_size;
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- "Failed checksum validation on tunnel %s with KX\n" place,
+ "Failed checksum validation on tunnel %s with KX\n",
GCT_2s (t));
GNUNET_STATISTICS_update (stats, "# wrong HMAC", 1, GNUNET_NO);
return -1;
}
-
/**
* Handle a channel destruction message.
*
send_pong (t, res.nonce);
}
+/**
+ * @brief Finish the Key eXchange and destory the old keys.
+ *
+ * @param cls Closure (Tunnel for which to finish the KX).
+ * @param tc Task context.
+ */
+static void
+finish_kx (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct CadetTunnel *t = cls;
+
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+ return;
+
+ GNUNET_free (t->kx_ctx);
+ t->kx_ctx = NULL;
+}
/**
}
GNUNET_SCHEDULER_cancel (t->rekey_task);
t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
- GNUNET_free (t->kx_ctx);
- t->kx_ctx = NULL;
+
+ /* Don't free the old keys right away, but after a delay.
+ * Rationale: the KX could have happened over a very fast connection,
+ * with payload traffic still signed with the old key stuck in a slower
+ * connection.
+ */
+ if (GNUNET_SCHEDULER_NO_TASK == t->kx_ctx->finish_task)
+ {
+ t->kx_ctx->finish_task =
+ GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_MINUTES, finish_kx, t);
+ }
GCT_change_estate (t, CADET_TUNNEL3_KEY_OK);
}
{
GNUNET_SCHEDULER_cancel (t->rekey_task);
t->rekey_task = GNUNET_SCHEDULER_NO_TASK;
- if (NULL != t->kx_ctx)
- GNUNET_free (t->kx_ctx);
- else
- GNUNET_break (0);
}
-
+ if (NULL != t->kx_ctx)
+ {
+ if (GNUNET_SCHEDULER_NO_TASK != t->kx_ctx->finish_task)
+ GNUNET_SCHEDULER_cancel (t->kx_ctx->finish_task);
+ GNUNET_free (t->kx_ctx);
+ }
GNUNET_free (t);
}