This patch largely reverts the commit "base: lay groundwork for
base-linux caps change" because the use of 'epoll' instead of 'select'
alleviated the need to allocate large FD sets, which motivated the
introduction of the 'Native_context' hook.
Related to issue #3581
The sandbox library supports the forwarding of session requests from the
outside to one of the hosted children according to a policy. This patch
introduces the distinction between two cases, which previously triggered
the denial of the session request.
- There exists no matching policy for the requested session
- There exists a matching policy but the referred server child
does not exist (yet)
Whereas the proper response to the first case is the denial of the
request, the second case can occur in situation where a dynamic init is
used to implement a staged startup, for example via the deploy
mechanism. In such cases, a policy may exist as a static rule while the
server has not been started yet. This patch changes the behavior such
that such requests are stalled.
The patch is accompanied with test cases for exercising both situations.
Fixes#3733
If trace is enabled for component than an attempt to put message into
trace buffer is performed using log_output policy. If it succeeds than
message is not put to logs using log service.
Fixes#3714
On Linux, Genode used to represent each RPC object by a socket
descriptor of the receiving thread (entrypoint) and a globally-unique
value that identifies the object. Because the latter was transferred as
plain message payload, clients had to be trusted to not forge the
values. For this reason, Linux could not be considered as a productive
Genode base platform but remained merely a development vehicle.
This patch changes the RPC mechanism such that each RPC object is
represented by a dedicated socket pair. Entrypoints wait on a set of
the local ends of the socket pairs of all RPC objects managed by the
respective entrypoint. The epoll kernel interface is used as the
underlying mechanism to wait for a set of socket descriptors at the
server side.
When delegating a capability, the remote end of the socket pair is
transferred to the recipient along with a plaintext copy of the
socket-descriptor value of the local end. The latter value serves as a
hint for re-identifiying a capability whenever it is delegated back to
its origin. Note that the client is not trusted to preserve this
information. The integrity of the hint value is protected by comparing
the inode values of incoming and already present capablities at the
originating site (whenever the capability is invoked or presented to the
owner of the RPC object).
The new mechanism effectively equips base-linux with Genode's capablity
model as described in the Chapter 3 of the Genode Foundations book.
That said, the sandboxing of components cannot be assumed at this point
because each component has still direct access to the Linux system-call
interface.
This patch is based on the extensive exploration work conducted by
Stefan Thoeni who strongly motivated the inclusion of this feature into
Genode.
Issue #3581
Older ARM processors like ARMv6, or Cortex A8 need to write back changes
of the page-tables to physical ram because the MMU does not use the cache.
This naturally needs to be done not only when adding a mapping,
but on removal too.
Fix#3715
The topics are either covered by the Genode Founations book for by our
tools, in particular the integration of the prepare_port mechanism with
the run tool.
- don't use 'qemu -serial mon:stdio' anymore as it no longer works as
expected
- use "bash -l" with [terminal] to read user's profile configuration,
e.g., PATH settings
- added missing boot modules and cap quotas
This commit puts all C++ runtime/support symbols of ld.lib.so in a
dedicated section of base/lib/symbols/ld and mirrors the section to
libports/lib/symbols/libc. So, the libc ABI resolves potential C++
runtime dependencies of base-ABI-agnostic components at link time. The
runtime resolution is done by the linker by symbol lookup in ld.lib.so.
Issue #3720
config_0.xml.tmp:26: element config: Schemas validity error :
Element 'config': Character content other than whitespace is
not allowed because the content type is 'element-only'
Issue #3612
