This resolves a medium vulnerability described in the
Beast Hybrid Assessment Report by Bishop Fox, where masks generated
for use with outgoing WebSocket client frames use an insufficient
source of entropy and a non-cryptographically secure pseudo-random
number generator.
By default, all newly constructed WebSocket streams will use a
uniquely seeded secure PRNG (ChaCha20 in counter mode). As this may
result in increased CPU resource consumption, the function
websocket::stream::secure_prng() may be used to select a faster but
less secure PRNG, for the case where the caller knows that the secure
generator is not necessary.
On some systems, std::random_device may produce insufficient entropy
to securely seed the PRNG. As this condition cannot be detected by
Beast, callers may use the function websocket::seed_prng() called
once at startup to provide at least 256 bits of entropy which will
be used to uniquely seed all subsequent PRNGs.
fix#1076
As per Asio and Networking TS requirements, composed operations must
maintain an object of type executor_work_guard for the executor associated
with the I/O object, for the lifetime of the asynchronous operation.
This is in addition to the requirement for maintaining an object of type
executor_work_guard for the executor associated with the handler.
fix#941, fix#1016
`get_lowest_layer` is now a type alias for the
lowest layer instead of a struct with a nested type.
Actions required:
* Replace instances of `typename get_lowest_layer<T>::type`
with `get_lowest_layer<T>`.
In Boost.System, `boost::system::errc` is a namespace
containing ints. In C++11, std::errc is an enum marked
as an `error_condition`.
`error_code::assign` is specified as taking an int only,
while make_error_code is able to deal correctly with both forms.
fix#930
* The function serializer::reader_impl is deprecated and will
be removed in a subsequent version.
* Some private symbols used in the implementation were
also renamed to reflect correct terminology.
Actions Required:
* Call serializer::writer_impl instead of reader_impl
* The handler_ptr constructor now provides the
strong exception guarantee.
* The signature for managed objects constructed by
`handler_ptr` receives a const reference to the handler.
Actions required:
* Change the constructor signature for state objects
used with handler_ptr to receive a const reference to
the handler.
Glen Fernandes
Vinnie Falco
Damian Jarek
Daniel James
Paul "TBBle" Hampson
zerotypos-found
Sergey M․
Berkus Decker