From 20c1ca2aaec2ead2d0182fc248614819ae3ddf54 Mon Sep 17 00:00:00 2001 From: Nicolas Werner Date: Tue, 20 Apr 2021 14:19:07 +0200 Subject: [PATCH] Fix a a session with a higher minimum index being able to overwrite an older one --- src/Cache.cpp | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/src/Cache.cpp b/src/Cache.cpp index 44b7d246..9e9e1586 100644 --- a/src/Cache.cpp +++ b/src/Cache.cpp @@ -374,6 +374,18 @@ Cache::saveInboundMegolmSession(const MegolmSessionIndex &index, const auto pickled = pickle(session.get(), SECRET); auto txn = lmdb::txn::begin(env_); + + std::string_view value; + if (inboundMegolmSessionDb_.get(txn, key, value)) { + auto oldSession = unpickle(std::string(value), SECRET); + if (olm_inbound_group_session_first_known_index(session.get()) > + olm_inbound_group_session_first_known_index(oldSession.get())) { + nhlog::crypto()->warn( + "Not storing inbound session with newer first known index"); + return; + } + } + inboundMegolmSessionDb_.put(txn, key, pickled); txn.commit(); }