Introduce the uplink tag:
! <config>
! <uplink label="wifi" domain="uplink">
! <uplink label="wired" domain="wired_bridge">
! <uplink domain="wired_bridge">
! <config/>
For each uplink tag, the NIC router requests a NIC session with the
corresponding label or an empty label if there is no label attribute.
These NIC sessions get attached to the domain that is set in their
uplink tag as soon as the domain appears. This means their lifetime is
not bound to the domain. Uplink NIC sessions can be safely moved from
one domain to another without being closed by reconfiguring the
corresponding domain attribute.
Attention: This may render previously valid NIC router configurations
useless. A domain named "uplink" doesn't automatically request a NIC
session anymore. To fix these configurations, just add
! <uplink domain="uplink"/>
or
! <uplink label="[LABEL]" domain="uplink"/>
as direct subtag of the <config> tag.
Issue #2840
* Catch Quota_guard exceptions wherever we do 'new (_alloc)' in Interface
and in case drop the packet that caused the exception
* Modify Interface::handle_config_2 to not use the guarded allocator of the
NIC session quota as we cannot handle a RAM exhaustion well at this point
in time. Instead use a Constructible member in Interface so that a needed
RAM adds up to the calculation in the create_session implementation where
an exhaustion is handled via a service denial.
Issue #2857
The interface destructor called pure virtual methods at least when
cancelling ARP- waiting states. The implementations were made by the
deriving classes Session_component respectively Uplink. This led to an
abort of the NIC router as the destruction of the derived class was
already done. A similar problem already occured in the past during the
construction of Interface and was back then solved by introducing a
separate init() method. This commit, however, solved the problem by
making Interface a member of the other classes. Therefore, the init()
method could be removed again. Furthermore, the interface polica could be
moved from Session_component_base to Session_component. The commit also
had to generalize the way the link state of an interface is determined.
Fixes#2856
* Get rid of the base classes Rule and Leaf_rule,
* Make log output about initiated or invalid routing rules conform to the rest
of the router log, and
* Ensure that each type of routing rule when being invalid invalidates its
whole domain.
Issue #2840
Do not send nor buffer packets at interfaces with link state "down". This
prevents that packets that were routed to one network (allowed to see them),
due to a sudden link down/up, are leaked to another network that is not
allowed to see them.
When updating an interface in the NIC router to a new configuration and
the domain name of the interface has not changed but the domain
disappeared, the NIC router did not detach from the old domain correctly
which led to broken remnants of interface state objects (like connection
states).
Adapt the nic_router_uplinks run script to work with the fix.
When re-configuring the NIC router, determine for each domain if at least one
interface stays with the domain. If a domain fullfills this and has a
dynamic IP config (received via a DHCP client), keep the IP config.
To achieve this, the following changes have been made to the existing NIC
router code:
* Split-up Interface::handle_config into three steps:
1) Determine for each interface if its domain can keep its IP config or
or if it has to mark it invalid. This must be done before (re-)attaching
any interface because during "attach" several decisions are made based on
the validity of the IP config of corresponding the domain.
(E.g. whether to participate in sending DHCP DISCOVERs {IP config
invalid} or whether to participate in sending pending ARP REQUESTs
{IP config valid} ).
2) Detach, attach, or re-attach each interface according to the
configuration. This must be done before re-considering the temporary
state objects of each interface because the latter might have effects
on the interfaces of remote domains which must then be in place already.
3) Re-consider temporary state objects of each interface. (E.g. transport
layer connection states)
* Re-work IP-config setter in a way that it works as follows:
1) If the old IP config is valid, let all local interfaces as well as remote
interfaces that depend on the IP config of the domain detach from the old
IP config.
2) Overwrite with new IP config
3) If the new IP config is valid, let all local interfaces as well as remote
interfaces that depend on the IP config of the domain attach to the new
IP config.
Issue #2815
The Ethernet destination MAC address of a DHCP reply is not the same as the
DHCP client MAC address. The DHCP server of the NIC router did not take care
of this by now.
Issue #2837
Instead of handing over the maximum available size to the packet data
accessors, hand over a size guard that keeps track of the packets
boundaries.
This commit also moves the size-guard utilitiy header of Ping and NIC
Router to the include/net directory making it a part of the net library.
It applies the new approach to all net-lib users in the basic repositories.
Ping looses its configurability regarding the ICMP data size as this would
require an additional method in the size guard which would be used only by
Ping.
The size guard was also re-worked to fit the fact that a packet can
bring a tail as well as a header (Ethernet).
Issue #2788
This follows the guidelines in RFC 5508 to enable forwarding of ICMP
"Destination Unreachable" that correspond to an existing link state in
the NIC router. It also serves as blueprint for forwarding ICMP error
messages in general (They are merely not enabled because we don't test
them).
Issue #2732
This follows the guidelines in RFC 5508 to enable ICMP echo through a NAPT
channel of the NIC router. It serves also as blueprint for ICMP queries in
general (they are merely not enabled because we don't test them by now).
Issue #2732
If the remote DNS server address value of a DHCP server changes, the affected
interfaces do a link down/up to inform all DHCP clients that they should
re-request their DHCP info.
Issue #2730
The Interface constructor previously tried to attach to a domain. This
might include sending a DHCP request to get the domain a valid IP config.
But in order to achieve this, the constructor used a pure virtual method
of Interface which crashes due to the unfinished vtable. To fix this bug,
the attach attempt was moved to a new Interface::init method.
Issue #2730
Instead of Pointer<T>::set use assignment operator with implicit constructor
from T-reference. Instead of Pointer<T>::unset use assignment operator with
Pointer<T>(). Instead of Pointer<T>::deref provide () operator.
Issue #2730
The router reacts as follows to a configuration change:
1) Construct new internal configuration representation (the old one stays
in place to be able to do comparisons in the following steps)
2) Iterate through all user-dependent objects (interfaces, link states, ARP
information, DHCP information) and re-check which remain valid with the
new configuration and which must be dismissed.
3) Adapt the objects that remain valid to the new configuration (re-write
references) and remove or detach the dismissed objects.
4) Do a link state DOWN at each interface and a link state UP at each
interface that remains attached to a domain.
5) Replace the old internal configuration representation with the new one
This way, the router keeps as much user dependent states as possible
while going through a configuration change. Thus, overwriting the old
configuration with an exact copy of itself is (almost) transparent to
clients of the router. Almost, because there are things the router must
do on every configuration handling, like re-scheduling the expiration
timeouts of links.
Ref #2670
Clients can connect at any time to the NIC router. The interfaces (sessions)
get attached to the appropriate domain as soon as it appears. This implies
that interfaces can also be detached from a domain without beeing destructed
when the domain disappears. All user dependent states of an interface such as
the link states, DHCP allocations and ARP information get lost when the
interface gets detached.
Ref #2670
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:
* A class with virtual functions can no longer publicly inherit base
classed without a vtable. The inherited object may either be moved
to a member variable, or inherited privately. The latter would be
used for classes that inherit 'List::Element' or 'Avl_node'. In order
to enable the 'List' and 'Avl_tree' to access the meta data, the
'List' must become a friend.
* Instead of adding a virtual destructor to abstract base classes,
we inherit the new 'Interface' class, which contains a virtual
destructor. This way, single-line abstract base classes can stay
as compact as they are now. The 'Interface' utility resides in
base/include/util/interface.h.
* With the new warnings enabled, all member variables must be explicitly
initialized. Basic types may be initialized with '='. All other types
are initialized with braces '{ ... }' or as class initializers. If
basic types and non-basic types appear in a row, it is nice to only
use the brace syntax (also for basic types) and align the braces.
* If a class contains pointers as members, it must now also provide a
copy constructor and assignment operator. In the most cases, one
would make them private, effectively disallowing the objects to be
copied. Unfortunately, this warning cannot be fixed be inheriting
our existing 'Noncopyable' class (the compiler fails to detect that
the inheriting class cannot be copied and still gives the error).
For now, we have to manually add declarations for both the copy
constructor and assignment operator as private class members. Those
declarations should be prepended with a comment like this:
/*
* Noncopyable
*/
Thread(Thread const &);
Thread &operator = (Thread const &);
In the future, we should revisit these places and try to replace
the pointers with references. In the presence of at least one
reference member, the compiler would no longer implicitly generate
a copy constructor. So we could remove the manual declaration.
Issue #465
Normally, Interface::send always takes the base and size of the RAM region
where a packet was composed and copies this finished packet at once into the
packet stream RAM. But we want to be able to also compose packets directly in
the packet stream RAM, so that no memcpy is needed. Thus, Interface::send now
takes a functor that describes how to compose the packet, then allocates the
packet stream RAM and applies the functor to this RAM. there is also a version
of Interface::send that provides the old behavior but with the new back end.
This way, we stay backwards-compatible.
Issue #2626
In the context of link state objects we often used the term "close" were we
actually meant "dissolve". The term "close" originated from the TCP connection
state and is still used in TCP links in the correct manner.
Issue #2609
Act as hub for the interfaces at a domain. This also changes the roles of the
Domain and Interface classes. By now the Interface held the data structures for
the ARP cache, foreign ARP waiters, and the searchtrees for layer 3 links. All
these structures have moved to the Domain while the memory allocations and
lifetime management for the contents of these structures still come from from
the according Interface object. The mentioned data structures were also adapted
to fit the fact that they now may maintain objects of different interfaces.
Issue #2609
Improve ARP handling code in general:
Make the several cases and their handling more clear by using a more
readable if/else statement structure. Drop gratuitous ARP requests.
Domain-local ARP:
Handle ARP packets that target local IPs other than the routers IP
(forward them to all other interfaces of the domain).
Issue #2609
If a client decides to spontaneously send a DHCP DISCOVER again, even though
he has received a still valid IP config from the router, we don't want to
discard the DISCOVER like it was done before but discard the IP config
assignment and offer a new one.
Issue #2534
If the attribute 'interface' is not set in a 'domain' tag, the router tries to
dynamically receive and maintain an IP configuration for that domain by using
DHCP in the client role at all interfaces that connect to the domain. In the
DHCP discover phase, the router simply chooses the first DHCP offer that
arrives. So, no comparison of different DHCP offers is done. In the DHCP
request phase, the server is expected to provide an IP address, a gateway, a
subnet mask, and an IP lease time to the router. If anything substantial goes
wrong during a DHCP exchange, the router discards the outcome of the exchange
and goes back to the DHCP discover phase. At any time where there is no valid
IP configuration present at a domain, the domain does only act as DHCP client
and all other router functionality is disabled for the domain. A domain cannot
act as DHCP client and DHCP server at once. So, a 'domain' tag must either
have an 'interface' attribute or must not contain a 'dhcp-server' tag.
Ref #2534
An IPv4 config (for a domain/interface of the router) consists of
an IPv4 address, a subnet prefix specifier, an optional gateway
IPv4 address, and some flags that declare whether these fields and
the config as a whole are valid. To make the handling of those
tightly connected values easier and less error prone, we encapsulate
them in a new class.
Ref #2534
One can configure the NIC router to act as DHCP server at interfaces of a
domain by adding the <dhcp> tag to the configuration of the domain like
this:
<domain name="vbox" interface="10.0.1.1/24">
<dhcp-server ip_first="10.0.1.80"
ip_last="10.0.1.100"
ip_lease_time_sec="3600"
dns_server="10.0.0.2"/>
...
</domain>
The attributes ip_first and ip_last define the available IPv4 address
range while ip_lease_time_sec defines the lifetime of an IPv4 address
assignment in seconds. The IPv4 address range must be in the subnet
defined by the interface attribute of the domain tag and must not cover
the IPv4 address in this attribute. The dns_server attribute gives the
IPv4 address of the DNS server that might also be in another subnet.
The lifetime of an offered assignment is the configured round trip time of
the router while the ip_lease_time_sec is applied only if the offer is
requested by the client in time.
The ports/run/virtualbox_nic_router.run script is an example of how to
use the new DHCP server functionality.
Ref #2490
Apply the style rule that an accessor is named similar to the the underlying
value. Provide read and write accessors for each mandatory header attribute.
Fix some incorrect structure in the headers like with the flags field
in Ipv4_packet.
Ref #2490
Do not stop routing if the transport layer protocol is unknown but
continue with trying IP routing instead. The latter was already
done when no transport routing could be applied but for unknown transport
protocols we caught the exception at the wrong place.
Ref #2490
Previously, the Genode::Timer::curr_time always used the
Timer_session::elapsed_ms RPC as back end. Now, Genode::Timer reads
this remote time only in a periodic fashion independently from the calls
to Genode::Timer::curr_time. If now one calls Genode::Timer::curr_time,
the function takes the last read remote time value and adapts it using
the timestamp difference since the remote-time read. The conversion
factor from timestamps to time is estimated on every remote-time read
using the last read remote-time value and the timestamp difference since
the last remote time read.
This commit also re-works the timeout test. The test now has two stages.
In the first stage, it tests fast polling of the
Genode::Timer::curr_time. This stage checks the error between locally
interpolated and timer-driver time as well as wether the locally
interpolated time is monotone and sufficiently homogeneous. In the
second stage several periodic and one-shot timeouts are scheduled at
once. This stage checks if the timeouts trigger sufficiently precise.
This commit adds the new Kernel::time syscall to base-hw. The syscall is
solely used by the Genode::Timer on base-hw as substitute for the
timestamp. This is because on ARM, the timestamp function uses the ARM
performance counter that stops counting when the WFI (wait for
interrupt) instruction is active. This instruction, however is used by
the base-hw idle contexts that get active when no user thread needs to
be scheduled. Thus, the ARM performance counter is not a good choice for
time interpolation and we use the kernel internal time instead.
With this commit, the timeout library becomes a basic library. That means
that it is linked against the LDSO which then provides it to the program it
serves. Furthermore, you can't use the timeout library anymore without the
LDSO because through the kernel-dependent LDSO make-files we can achieve a
kernel-dependent timeout implementation.
This commit introduces a structured Duration type that shall successively
replace the use of Microseconds, Milliseconds, and integer types for duration
values.
Open issues:
* The timeout test fails on Raspberry PI because of precision errors in the
first stage. However, this does not render the framework unusable in general
on the RPI but merely is an issue when speaking of microseconds precision.
* If we run on ARM with another Kernel than HW the timestamp speed may
continuously vary from almost 0 up to CPU speed. The Timer, however,
only uses interpolation if the timestamp speed remained stable (12.5%
tolerance) for at least 3 observation periods. Currently, one period is
100ms, so its 300ms. As long as this is not the case,
Timer_session::elapsed_ms is called instead.
Anyway, it might happen that the CPU load was stable for some time so
interpolation becomes active and now the timestamp speed drops. In the
worst case, we would now have 100ms of slowed down time. The bad thing
about it would be, that this also affects the timeout of the period.
Thus, it might "freeze" the local time for more than 100ms.
On the other hand, if the timestamp speed suddenly raises after some
stable time, interpolated time can get too fast. This would shorten the
period but nonetheless may result in drifting away into the far future.
Now we would have the problem that we can't deliver the real time
anymore until it has caught up because the output of Timer::curr_time
shall be monotone. So, effectively local time might "freeze" again for
more than 100ms.
It would be a solution to not use the Trace::timestamp on ARM w/o HW but
a function whose return value causes the Timer to never use
interpolation because of its stability policy.
Fixes#2400
The nic_router component can be used to individually route IPv4 packets
between multiple NIC sessions. Thereby, it can translate between
different IP subnets. The component supports port forwarding, as well as
the partitioning of the TCP and UDP port spaces.
Fixes#114
