Fuzz-testing of various parsers, mocked examples and system libraries

A secure web server must be capable of receiving mass amount of malicious input without misbehaving or performing illegal actions, such as stepping outside of a memory block or otherwise spilling the beans.

Continuous fuzzing under various sanitizers is done as part of the Google OSS-Fuzz project:

• UndefinedBehaviorSanitizer
• AddressSanitizer
• MemorySanitizer

Overall coverage is about 95% for both uSockets and uWebSockets, all source code included

• No defects or outstanding bugs
• No timeouts, OOM, crashes or other issues
• Transparent reporting of found issues: https://bugs.chromium.org/p/oss-fuzz/issues/list?q=label%3AProj-uwebsockets&can=1

Currently the following parts are individually fuzzed:

• WebSocket handshake generator
• WebSocket message parser
• WebSocket extensions parser & negotiator
• WebSocket permessage-deflate compression/inflation helper
• Http parser (with and without Proxy Protocol v2)
• Http method/url router
• Pub/sub "topic tree"

While some targets are entire (mocked) example apps

• libEpollFuzzer mocks the kernel syscalls and allows to cover a lot of uSockets source code.
• A mock implementation of uSockets allows to cover a lot of the inbetween logic of uWebSockets.