The guest network stack might DHCPREQUEST an address that the slirp built
in dhcp server can't let it have - for example if the guest has an old
leases file from another network configuration. In this case the dhcp
server should and does reject the request and prepares to send a DHCPNAK
to the client.
However, in this case the daddr variable in bootp_reply() is set to
0.0.0.0. Shortly afterwards, it unconditionally attempts to pre-insert the
new client address into the ARP table. This causes an assertion failure in
arp_address_add() because of the 0.0.0.0 address.
According to RFC2131, DHCPNAK messages for clients on the same subnet
must be sent to the broadcast address (S3.2, subpoint 2).
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
This patch adds a simple ARP table in Slirp and also adds handling of
gratuitous ARP requests.
Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
make the code compile correctly when DEBUG is activated.
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Slirp code tries to be smart an avoid data copy by using pointer to
the data. This solution leads to unaligned access, in this case
preq_addr, which is a 32-bit long structure. There is no real point
of avoiding data copy in a such case, as the value itself is smaller
or the same size as a pointer.
The patch replaces pointers to the preq_addr structure by the strcture
itself, and use the address 0.0.0.0 if no address has been requested
(this is not a valid address in such a request). It compares it with
htonl(0L) for correctness reasons, in case a code checker look for such
mistakes. It also uses memcpy() for copying the data, which takes care
of alignement issues.
This fixes an unaligned access on IA64 host while requesting a DHCP
address.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
The essence of this patch is to stuff (almost) all global variables of
the slirp stack into the structure Slirp. In this step, we still keep
the structure as global variable, directly accessible by the whole
stack. Changes to the external interface of slirp will be applied in
the following patches.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The user mode IP stack is currently only minimally configurable /wrt to
its virtual IP addresses. This is unfortunate if some guest has a fixed
idea of which IP addresses to use.
Therefore this patch prepares the stack for fully configurable IP
addresses and masks. The user interface and default addresses remain
untouched in this step, they will be enhanced in the following patch.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
So far a couple of slirp-related parameters were expressed via
stand-alone command line options. This it inconsistent and unintuitive.
Moreover, it prevents both dynamically reconfigured (host_net_add/
delete) and multi-instance slirp.
This patch refactors the configuration by turning -smb, -redir, -tftp
and -bootp as well as -net channel into options of "-net user". The old
stand-alone command line options are still processed, but no longer
advertised. This allows smooth migration of management applications to
to the new syntax and also the extension of that syntax later in this
series.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
In case a client restarts a DHCP recovery without releasing its old
address, reassign the same address to prevent consuming free addresses
and moving away from the standard client address.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
This adds proper handling of the ciaddr field as well as the "Requested
IP Address" option to slirp's DHCP server. If the client requests an
invalid or used IP, a NAK reply is sent, if it requests a specific but
valid IP, this is now respected.
NAK'ing invalid IPs is specifically useful when changing the slirp IP
range via '-net user,ip=...' while the client saved its previously used
address and tries to reacquire it. Now this will be NAK'ed and the
client will start a new discovery round.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7198 c046a42c-6fe2-441c-8c8c-71466251a162
Windows Vista drops unicast dhcp replies to its yet-unconfigured address,
so use a broadcast address. This behaviour is allowed by the RFC.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6430 c046a42c-6fe2-441c-8c8c-71466251a162
David Gibson