The NIC router used to send an ICMP "Destination Unreachable" packet as
response to every unroutable IPv4 packet. However, RFC 1812 section 4.3.2.7
defines certain properties that must be fullfilled by an incoming packet in
order to be answered with this type of ICMP. One requirement is that the packet
is no IPv4 multicast.
This commit prevents sending the mentioned ICMP response for unroutable IPv4
multicasts and instead drops them silently.
Fixes#4563
The checksums for forwarded/routed UDP, TCP and ICMP, used to be always
re-calculated from scratch in the NIC router although the router changes only
a few packet fields. This commit replaces the old approach whereever sensible
with an algorithm for incremental checksum updates suggested in RFC 1071.
The goal is to improve router performance.
Ref #4555
The checksums for forwarded/routed IPv4, used to be always re-calculated from
scratch in the NIC router although the router changes only a few packet fields.
This commit replaces the old approach whereever sensible with an algorithm for
incremental checksum updates suggested in RFC 1071. The goal is to improve
router performance.
Ref #4555
* Adds methods for copying raw data to the data field of Ethernet frames and
UDP packets. This is used in the port to wrap the higher-layer packet data
prepared by the contrib code with the additionally required headers before
sending it at a network session.
* Adds a method to cast raw data to an IPv4 packet. This is required in the
port in order to check values in stand-alone IP packets produced by the
contrib code before sending them at a network session.
* Adds methods for setting UDP ports given big endian port values without
having to convert to little endian in the app and then back to big endian in
the net lib.
Ref #4397
The former declaration of the IPv4 packet did not only use the questionable
tool of implementation-defined C++ bitsets but also lacked access to flags
"don't fragment" (DF) and "more fragments" (MF). This commit replaces the
C++ bitsets by using the register framework and introduces accessors for the
missing flags.
Ref #4236
The combination of Net::Mac_address and
Genode::ascii_to(Net::Mac_address) required shaky quirks in several
places because GCC is not able to resolve the ascii_to overload if
base/xml_node.h was included to early. The current solution moves the
several ascii_to overloads "closer" to the Net types by putting them
into the Net namespace, where GCC reliably picks them up.
Hence, co-locating the ascii_to() utility with the overload type in the
same scope/namespace is good practice.
This patch removes the now obsolete <nic/xml_node.h> header file.
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
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
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
Both methods are now available for Ipv4_address as well as for
Ipv4_address_prefix. An IPv4 address is invalid if it contains zeros only.
An IPv4 address prefix is invalid if its address is invalid and its
prefix is 32.
Ref #2139
* use Component::* instead of Server::*
* do not use old printf format anymore
* do not use old Genode::env()->heap() anymore
* avoid pointers where possible, and use references instead
* throw away the thread-safe variants of list and AVL tree,
nic_bridge became single-threaded in the past
* introduce Ram_session_guard instead of Allocator_guard
Issue #1987
Replace size_t by uint8_t in accessors for the IPv4 header fields
'version' and 'header_length' - uint8_t is the smallest integral type
for 4 bit of information. Note, as the _internet header length_ field is
defined to reflect the number of 32-bit words the header occupies, we
also stick to the specification with our accessor.
Issue #1915
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.
Issue #1082