Some application code is dereferencing the pointer returned by
'packet_content' at packet streams without checking that it is valid.
Throw an exception rather than return a null pointer, except for
zero-length packets, which have somewhat implicit invalid content and
that we believe to be properly handled in all current cases.
The client-side of a packet stream cannot take corrective action if the
server-side is sending packets with invalid content, but the servers
that provide packet streams should catch this exception to detect
misbehaving clients.
Ref #3059
* Account all RAM/CAP quota of a session except quota for metadata used in
core. The latter is considered when asking if a session can afford to make
an operation but it does not get accounted to always be able to pay back all
quota when a session closes. The general accounting mechanism is moved from
atop of the allocators down to the level of RAM/RM session operations.
* report statistics about session objects and quota if <report stats="yes"
quota="yes"/> is configured. (default is yes if <report> is present)
Issue #2953
If the NIC router has insufficient CAP or RAM quota for the creation of
a state object for an interface, it tries to destroy a certain amount of
existing state objects of this interface to free resources. Afterwards,
it retries handling the current packet once. If it does fail again, the
router drops the packet.
Issue #2953
The log messages covered by verbose_packet_drop were previously
configured by the verbose attribute. This isn't the case anymore. Now,
you can configure them as follows:
! <config verbose_packet_drop="no" ... >
! <domain verbose_packet_drop="no" ... />
! <config/>
The new attribute determines whether to log each packet drop and the
rational behind it. The <config> value affects all domains without a
<domain> local value.
Issue #2857
The ICMP-Echo-server functionality of the router has the following
configuration attributes (default values shown):
! <config icmp_echo_server="yes">
! <domain icmp_echo_server="yes" ... />
! </config>
The icmp_echo_server attribute configures whether the router answers ICMP Echo
requests that address the router. The <config> value affects all domains
without a <domain> local value.
Issue #2874
* Do not log events that are not critical (deadly) to the NIC router if not
configured to be verbose,
* Print almost all log lines with a prefix of the domain name they are
related to,
* And, do not use Genode::error and Genode::warning as they make it hard to
read the log with the domain name prefixes.
Fixes#2840
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
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
Allocate a virtual MAC address at runtime that is used as router
Ethernet-identity for all downlink domains. This makes the downlink
domains independent from the uplink session.
Issue #2795
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
The Ethernet payload may be followed by padding of variable length and
the FCS (Frame Check Sequence). Thus, we should consider the value
"Ethernet-frame size minus Ethernet-header size" to be only the maximum
size of the encapsulated IP packet. But until now, we considered it to
be also the actual size of the encapsulated IP packet. This commit fixes
the problem for all affected components of the Genode base-repository.
Fixes#2775
This reduces the redundant implementations of checksum calculation to
one generic implementation, makes the checksum interface conform over
all protocols, and brings performance optimizations. For instance,
the checksum is now calculated directly in big endian which saves us
most of the previously done byte-re-ordering.
Issue #2775
Replace packet method 'T *data' by the new methods 'T &reinterpret_data'
for parsing or modifying existing sub-protocol packets and 'T
&construct_at_data' for composing a new sub-protocol packet. This has
the advantage that, when composing a new packet, the default constructor
that zero-fills the packet is always called first.
Fixes#2751
When having an interface that yet is not attached to a domain, then a new
configuration comes in and the interface receives a domain name (via the
policy tag) but the corresponding domain doesn't exist, an exception
Domain_tree::No_match is thrown but was not caught and handled until now.
Issue #2670
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
By now, the 'verbose packets' output when sending packets was printed after
finish sending the packet. This makes following the packet flow harder if you
have multiple components that print such information.
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
The 'verbose packets' output previously was not generated for Interfaces
without a domain. But this is desirable as the router nonetheless
receives packets at such interfaces. This is now fixed and such output
is simply prefixed with a "[?]" denoting that the interface has no
domain.
Issue #2732
We missed to zero-out the ECN field in IPv4 packets. We don't use the ECN
field but there might be old data left in the packet RAM allocated by the
NIC packet streams. If we don't zero-out ECN it might leak old data.
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
This separates the decision wether to log the received and sent packets
from the 'verbose' attribute. This information is now only logged if
'verbose_packets' is switched on. If 'verbose' is switched on, only
routing decisions and optional hints are printed.
Ref #2670
When a NIC session is destructed at the router, we have to remove all ARP
cache entries that match the MAC address of that session. Otherwise the
outdated entries might be re-applied later, leading to wrong destination
MAC addresses in routed packets.
Fixes#2637
Instead of having a method validate_size in each packet class, check
sizes in the data accessor of the surrounding packet class. This packet
accessor is the one that casts the data pointer to the desired data type
so it is sensible that it also checks whether the desired type would
exceed the available RAM before doing the cast. This also fits nicely
the fact that for the top-level packet-class of a packet, the size must
not be checked (which was previously done).
Issue #465
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
The warning "no interface connected to domain" was introduced when only one NIC
session at a time could be connected to a domain. It should help to track
packet drops that were caused by startup timing issues between servers and
clients. However, a user should watch the "NIC sessions" value of a domain
(verbose_domain_state) instead when debugging packet loss. With support for
multiple sessions per domain, even a non-empty domain may still miss the
session that connects the desired server.
Fix#2629
Previously, all packets that the router wanted to sent were first prepared to
their final state and then copied at once into the packet stream RAM. This is
fine for packets that the router only passes through with modifying merely
a few values. But for packets that the router writes from scratch on its own,
it is better to compose the packet directly in the packet stream RAM.
Fix#2626
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
When composing an ARP packet for sending, it's pointless to use the Arp_packet
constructor as the constructor only checks whether the packet is malformed.
Issue #2618
