Review usage of InternalError when parsing network traffic

Description

Creating issue for tracking purposes.

Reporter->InternalError denotes a fatal error, and will cause Bro to stop. Calling this function when parsing network traffic creates the possibility for an attacker using a "packet of death," which could stop Bro.

I suspect that in most cases, a weird should be generated instead, and Bro should just move on to the next packet. A quick grep shows some likely candidates for incorrect use of InternalError:

src/Sessions.cc: reporter->InternalError("Bad IP protocol version in DoNextInnerPacket");
src/Sessions.cc: reporter->InternalError("fragment block not in dictionary");
src/Sessions.cc: reporter->InternalError("fragment block missing");
src/Sessions.cc: reporter->InternalError("unknown transport protocol");
src/Frag.cc: reporter->InternalError("bad IP version in fragment reassembly");
src/IP.cc: reporter->InternalError("IPv6_HdrChain::Init with truncated IP header");
src/IP.cc: reporter->InternalError("IPv6_Hdr_Chain bad header %d", type);
src/IP.h: reporter->InternalError("bad IP version in IP_Hdr ctor");
src/RSH.cc: reporter->InternalError("multiple rsh client names");
src/RSH.cc: reporter->InternalError("multiple rsh initial client names");
src/POP3.cc: reporter->InternalError("command not known");
src/Rlogin.cc: reporter->InternalError("multiple rlogin client names");
src/ICMP.cc: reporter->InternalError("unexpected IP proto in ICMP analyzer: %d",
src/ICMP.cc: reporter->InternalError("unexpected next protocol in ICMP:eliverPacket()");
src/SMB.cc: reporter->InternalError("command mismatch for ParseTransaction");
src/HTTP.cc: reporter->InternalError("unrecognized HTTP message event");
src/HTTP.cc: reporter->InternalError("HTTP ParseRequest failed");
src/DPM.cc: reporter->InternalError("unknown protocol");
src/RPC.cc: reporter->InternalError("RPC underflow");
src/RPC.cc: reporter->InternalError("RPC resync: skipping over data failed");
src/RPC.cc: reporter->InternalError("inconsistent RPC record marker extraction");

Environment

None

Assignee

Robin Sommer

Reporter

Vlad Grigorescu

Labels

None

External issue ID

None

Components

Affects versions

Priority

Normal
Configure