On Windows a file descriptor is an int value allocated by the
local module instance of the C Run Time Library. A socket handle is a
SOCKET value allocated by a Winsock Provider for the requested family and
protocol. These two values cannot be mixed and there is no mechanism for
converting between the two. The _get_osfhandle() and _open_osfhandle()
functions can work with a standard HANDLE (file, pipe, etc) but cannot be
used for a SOCKET.
The Heimdal krb5_storage_from_fd() routine counted on the osf conversion
functions working on SOCKET values. Since they do not any attempt to call
krb5_storage_from_fd() on a socket resulted in an assertion being thrown
by the C RTL.
Another problem is SOCKET value truncation when storing a 64-bit value
into a 32-bit int.
To address these problems a new krb5_storage_from_socket() routine is
introduced. This routine setups a krb5_storage that stores a socket value
as a rk_socket_t and provides a set of helper routines that always use
network ready functions.
The krb5_storage_from_fd() routines no longer use net_read() and
net_write() but provide helpers that follow their logic so that pipes can
be processed.
All call sites that allocate a socket now store the socket as rk_socket_t
and call krb5_storage_from_socket().
All locations that previously called the bare close() on a socket value
now call rk_closesocket().
Change-Id: I045f775b2a5dbf5cf803751409490bc27fffe597
