memory DOS prevention

Prevent DOS of user side by limiting the size of the BackLog that
is maintained. This should not cause problems in even high latency
environments, and should prevent memory use > 16 mb.

The developer side does not keep much data, other than a list of the
Hashes of things it has recently sent, so is not susceptable to memory
DOS.

This commit was sponsored by Brock Spratlen on Patreon.

1 files changed, 9 insertions, 0 deletions

diff --git a/Memory.hs b/Memory.hs
new file mode 100644
index 0000000..963acf7
--- /dev/null
+++ b/Memory.hs
@@ -0,0 +1,9 @@
+module Memory where
+
+-- | Class of things whose size in memory is known.
+--
+-- (This can be an approximate size, but should be no larger than the
+-- memory used to reprecent the thing.)
+class DataSize t where
+	-- ^ Size in bytes
+	dataSize :: t -> Integer