RFC 3748 states that support for MD5-Challenge is mandatory for EAP
implementations. The MD5 and CHAP code is already included in the
default build since it is required by iSCSI, and so this does not
substantially increase the binary size.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow the ${netX/username} setting to be used to specify an EAP
identity to be returned in response to a Request-Identity, and provide
a mechanism for responding with a NAK to indicate which authentication
types we support.
If no identity is specified then fall back to the current behaviour of
not sending any Request-Identity response, so that switches will time
out and switch to MAC Authentication Bypass (MAB) if applicable.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
EAP responses (including our own) may be broadcast by switches but are
not of interest to us and can be safely ignored if received.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
EAP exchanges may take a long time to reach a final status, especially
when relying upon MAC Authentication Bypass (MAB). Our current
behaviour of sending EAPoL-Start every few seconds until a final
status is obtained can prevent these exchanges from ever completing.
Fix by redefining the EAP supplicant state to allow EAPoL-Start to be
suppressed: either temporarily (while waiting for a full EAP exchange
to complete, in which case we need to eventually resend EAPoL-Start if
the final Success or Failure packet is lost), or permanently (while
waiting for the potentially very long MAC Authentication Bypass
timeout period).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We have no way to force a link-layer restart in iPXE, and therefore no
way to explicitly trigger a restart of EAP authentication. If an iPXE
script has performed some action that requires such a restart
(e.g. registering a device such that the port VLAN assignment will be
changed), then the only means currently available to effect the
restart is to reboot the whole system. If iPXE is taking over a
physical link already used by a preceding bootloader, then even a
reboot may not work.
In the EAP model, the supplicant is a pure responder and never
initiates transmissions. EAPoL extends this to include an EAPoL-Start
packet type that may be sent by the supplicant to (re)trigger EAP.
Add support for sending EAPoL-Start packets at two-second intervals on
links that are open and have reached physical link-up, but for which
EAP has not yet completed. This allows "ifclose ; ifopen" to be used
to restart the EAP process.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Extend the EAP model to include a record of whether or not EAP
authentication has completed (successfully or otherwise), and to
provide a method for transmitting EAP responses.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Simplify the FCoE code by using driver-private data to hold the FCoE
port for each network device, instead of using a separate allocation.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Simplify the IPv6 link-local settings code by using driver-private
data to hold the settings block, instead of using a separate
allocation.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Simplify the LLDP code by using driver-private data to hold the LLDP
settings block, instead of using a separate allocation. This avoids
the need to maintain a list of LLDP settings blocks (since the LLDP
settings block pointer can always be obtained using netdev_priv()) and
obviates several failure paths.
Any recorded LLDP data is now freed when the network device is
unregistered, since there is no longer a dedicated reference counter
for the LLDP settings block. To minimise surprise, we also now
explicitly unregister the settings block. This is not strictly
necessary (since the block will be automatically unregistered when the
parent network device settings block is unregistered), but it
maintains symmetry between lldp_probe() and lldp_remove().
The overall reduction in the size of the LLDP code is around 15%.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow network upper-layer drivers (such as LLDP, which attaches to
each network device in order to provide a corresponding LLDP settings
block) to specify a size for private data, which will be allocated as
part of the network device structure (as with the existing private
data allocated for the underlying device driver).
This will allow network upper-layer drivers to be simplified by
omitting memory allocation and freeing code. If the upper-layer
driver requires a reference counter (e.g. for interface
initialisation), then it may use the network device's existing
reference counter, since this is now the reference counter for the
containing block of memory.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Define the IPv4 NTP server setting to simplify the use of a
DHCP-provided NTP server in scripts, using e.g.
#!ipxe
dhcp
ntp ${ntp}
Signed-off-by: Michael Brown <mcb30@ipxe.org>
A running link block timer holds a reference to the network device and
will prevent it from being freed until the timer expires. It is
impossible for free_netdev() to be called while the timer is still
running: the call to stop_timer() therein is therefore a no-op.
Stop the link block timer when the device is closed, to allow a
link-blocked device to be freed immediately upon unregistration of the
device. (Since link block state is updated in response to received
packets, the state is effectively undefined for a closed device: there
is therefore no reason to leave the timer running.)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Prepare for the possibility that a record handler may choose not to
consume the entire record by passing the I/O buffer and requiring the
handler to mark consumed data using iob_pull().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When a DHCP transaction does not result in the registration of a new
"proxydhcp" or "pxebs" settings block, any existing settings blocks
are currently left unaltered.
This can cause surprising behaviour. For example: when chainloading
iPXE, the "proxydhcp" and "pxebs" settings blocks may be prepopulated
using cached values from the previous PXE bootloader. If iPXE
performs a subsequent DHCP request, then the DHCP or ProxyDHCP servers
may choose to respond differently to iPXE. The response may choose to
omit the ProxyDHCP or PXEBS stages, in which case no new "proxydhcp"
or "pxebs" settings blocks may be registered. This will result in
iPXE using a combination of both old and new DHCP responses.
Fix by assuming that a successful DHCPACK effectively acquires
ownership of the "proxydhcp" and "pxebs" settings blocks, and that any
existing settings blocks should therefore be unregistered.
Reported-by: Henry Tung <htung@palantir.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Extend the request parameter mechanism to allow for arbitrary HTTP
headers to be specified via e.g.:
params
param --header Referer http://www.example.com
imgfetch http://192.168.0.1/script.ipxe##params
Signed-off-by: Michael Brown <mcb30@ipxe.org>
An attempt to use an existent but empty form parameter list will
currently result in an invalid POST request since the Content-Length
header will be missing.
Fix by using GET instead of POST if the form parameter list is empty.
This is a non-breaking change (since the current behaviour produces an
invalid request), and simplifies the imminent generalisation of the
parameter list concept to handle both header and form parameters.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We currently specify only the iSCSI default value for MaxBurstLength
and ignore any negotiated value, since our internal block device API
allows only for receiving directly into caller-allocated buffers and
so we have no intrinsic limit on burst length.
A conscientious target may however refuse to attempt a transfer that
we request for a number of blocks that would exceed the negotiated
maximum burst length.
Fix by recording the negotiated maximum burst length and using it to
limit the maximum number of blocks per transfer as reported by the
SCSI layer.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add support for recording LLDP packets and exposing TLV values via the
settings mechanism. LLDP settings are encoded as
${netX.lldp/<prefix>.<type>.<index>.<offset>.<length>}
where
<type> is the TLV type
<offset> is the starting offset within the TLV value
<length> is the length (or zero to read the from <offset> to the end)
<prefix>, if it has a non-zero value, is the subtype byte string of
length <offset> to match at the start of the TLV value, up to a
maximum matched length of 4 bytes
<index> is the index of the entry matching <type> and <prefix> to be
accessed, with zero indicating the first matching entry
The <prefix> is designed to accommodate both matching of the OUI
within an organization-specific TLV (e.g. 0x0080c2 for IEEE 802.1
TLVs) and of a subtype byte as found within many TLVs.
This encoding allows most LLDP values to be extracted easily. For
example
System name: ${netX.lldp/5.0.0.0:string}
System description: ${netX.lldp/6.0.0.0:string}
Port description: ${netX.lldp/4.0.0.0:string}
Port interface name: ${netX.lldp/5.2.0.1.0:string}
Chassis MAC address: ${netX.lldp/4.1.0.1.0:hex}
Management IPv4 address: ${netX.lldp/5.1.8.0.2.4:ipv4}
Port VLAN ID: ${netX.lldp/0x0080c2.1.127.0.4.2:int16}
Port VLAN name: ${netX.lldp/0x0080c2.3.127.0.7.0:string}
Maximum frame size: ${netX.lldp/0x00120f.4.127.0.4.2:uint16}
Originally-implemented-by: Marin Hannache <git@mareo.fr>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
RFC 2131 leaves undefined the behaviour of the client in response to a
DHCPNAK that comes from a server other than the selected DHCP server.
A substantial amount of online documentation suggests using multiple
independent DHCP servers with non-overlapping ranges in the same
subnet in order to provide some minimal redundancy. Experimentation
shows that in this setup, at least ISC dhcpd will send a DHCPNAK in
response to the client's DHCPREQUEST for an address that is not within
the range defined on that server. (Since the requested address does
lie within the subnet defined on that server, this will happen
regardless of the "authoritative" parameter.) The client will
therefore receive a DHCPACK from the selected DHCP server along with
one or more DHCPNAKs from each of the non-selected DHCP servers.
Filter out responses from non-selected DHCP servers before checking
for a DHCPNAK, so that these arguably spurious DHCPNAKs will not cause
iPXE to return to the discovery state.
Continue to check for DHCPNAK before filtering out responses for
non-selected lease addresses, since experimentation shows that the
DHCPNAK will usually have an empty yiaddr field.
Reported-by: Anders Blomdell <anders.blomdell@control.lth.se>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Move the platform-specific DHCP client architecture definitions to
header files of the form <ipxe/$(PLATFORM)/dhcparch.h>. This
simplifies the directory structure and allows the otherwise unused
arch/$(ARCH)/include/$(PLATFORM) to be removed from the include
directory search path, which avoids the confusing situation in which a
header file may potentially be accessed through more than one path.
For Linux userspace binaries on any architecture, use the EFI values
for that architecture by delegating to the EFI header file. This
avoids the need to explicitly select values for Linux userspace
binaries for each architecture.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Ensure that the "${netX/...}" settings mechanism always uses the same
interpretation of the network device corresponding to "netX" as any
other mechanism that performs a name-based lookup of a network device.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add the ability to automatically create a VLAN device for a specified
trunk device link-layer address and VLAN tag.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Many laptops now include the ability to specify a "system-specific MAC
address" (also known as "pass-through MAC"), which is supposed to be
used for both the onboard NIC and for any attached docking station or
other USB NIC. This is intended to simplify interoperability with
software or hardware that relies on a MAC address to recognise an
individual machine: for example, a deployment server may associate the
MAC address with a particular operating system image to be deployed.
This therefore creates legitimate situations in which duplicate MAC
addresses may exist within the same system.
As described in commit 98d09a1 ("[netdevice] Avoid registering
duplicate network devices"), the Xen netfront driver relies on the
rejection of duplicate MAC addresses in order to inhibit registration
of the emulated PCI devices that a Xen PV-HVM guest will create to
shadow each of the paravirtual network devices.
Move the code that rejects duplicate MAC addresses from the network
device core to the Xen netfront driver, to allow for the existence of
duplicate MAC addresses in non-Xen setups.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The network device index currently serves two purposes: acting as a
sequential index for network device names ("net0", "net1", etc), and
acting as an opaque unique integer identifier used in socket address
scope IDs.
There is no particular need for these usages to be linked, and it can
lead to situations in which devices are named unexpectedly. For
example: if a system has two network devices "net0" and "net1", a VLAN
is created as "net1-42", and then a USB NIC is connected, then the USB
NIC will be named "net3" rather than the expected "net2" since the
VLAN device "net1-42" will have consumed an index.
Separate the usages: rename the "index" field to "scope_id" (matching
its one and only use case), and assign the name without reference to
the scope ID by finding the first unused name. For consistency,
assign the scope ID by similarly finding the first unused scope ID.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
UEFI implements VLAN support within the Managed Network Protocol (MNP)
driver, which may create child VLAN devices automatically based on
stored UEFI variables. These child devices do not themselves provide
a raw-packet interface via EFI_SIMPLE_NETWORK_PROTOCOL, and may be
consumed only via the EFI_MANAGED_NETWORK_PROTOCOL interface.
The device paths constructed for these child devices may conflict with
those for the EFI_SIMPLE_NETWORK_PROTOCOL instances that iPXE attempts
to install for its own VLAN devices. The upshot is that creating an
iPXE VLAN device (e.g. via the "vcreate" command) will fail if the
UEFI Managed Network Protocol has already created a device for the
same VLAN tag.
Fix by providing our own EFI_VLAN_CONFIG_PROTOCOL instance on the same
device handle as EFI_SIMPLE_NETWORK_PROTOCOL. This causes the MNP
driver to treat iPXE's device as supporting hardware VLAN offload, and
it will therefore not attempt to install its own instance of the
protocol.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
All existing cipher suites use SHA-256 as the TLSv1.2 and above
handshake digest algorithm (even when using SHA-1 as the MAC digest
algorithm). Some GCM cipher suites use SHA-384 as the handshake
digest algorithm.
Allow the cipher suite to specify the handshake (and PRF) digest
algorithm to be used for TLSv1.2 and above.
This requires some restructuring to allow for the fact that the
ClientHello message must be included within the handshake digest, even
though the relevant digest algorithm is not yet known at the point
that the ClientHello is sent. Fortunately, the ClientHello may be
reproduced verbatim at the point of receiving the ServerHello, so we
rely on reconstructing (rather than storing) this message.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Always send the maximum supported version in our ClientHello message,
even when performing renegotiation (in which case the current version
may already be lower than the maximum supported version).
This is permitted by the specification, and allows the ClientHello to
be reconstructed verbatim at the point of selecting the handshake
digest algorithm in tls_new_server_hello().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow for AEAD cipher suites where the MAC length may be zero and the
authentication is instead provided by an authenticating cipher, with
the plaintext authentication tag appended to the ciphertext.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Harden against padding oracle attacks by treating invalid block
padding as zero length padding, thereby deferring the failure until
after computing the (incorrect) MAC.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Restructure the encryption and decryption operations to allow for the
use of ciphers where the initialisation vector is constructed by
concatenating the fixed IV (derived as part of key expansion) with a
record IV (prepended to the ciphertext).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
TLS stream and block ciphers use a MAC with a length equal to the
output length of the digest algorithm in use. For AEAD ciphers there
is no MAC, with the equivalent functionality provided by the cipher
algorithm's authentication tag.
Allow for the existence of AEAD cipher suites by making the MAC length
a parameter of the cipher suite.
Assume that the MAC key length is equal to the MAC length, since this
is true for all currently supported cipher suites.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
All TLS cipher types use a common structure for the per-record data
that is authenticated in addition to the plaintext itself. This data
is used as a prefix in the HMAC calculation for stream and block
ciphers, or as additional authenticated data for AEAD ciphers.
Define a "TLS authentication header" structure to hold this data as a
contiguous block, in order to meet the alignment requirement for AEAD
ciphers such as GCM.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Adjust the length of the first received ciphertext data buffer to
ensure that all decryption operations respect the cipher's alignment
size.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
TLS block ciphers always use CBC (as per RFC 5246 section 6.2.3.2)
with a record initialisation vector length that is equal to the cipher
block size, and no fixed initialisation vector.
The initialisation vector for AEAD ciphers such as GCM is less
straightforward, and requires both a fixed and per-record component.
Extend the definition of a cipher suite to include fixed and record
initialisation vector lengths, and generate the fixed portion (if any)
as part of key expansion.
Do not add explicit calls to cipher_setiv() in tls_assemble_block()
and tls_split_block(), since the constraints imposed by RFC 5246 are
specifically chosen to allow implementations to avoid doing so.
(Instead, add a sanity check that the record initialisation vector
length is equal to the cipher block size.)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The TLSv1.0 protocol was deprecated by RFC 8996 (along with TLSv1.1),
and has been disabled by default in iPXE since commit dc785b0fb
("[tls] Default to supporting only TLSv1.1 or above") in June 2020.
While there is value in continuing to support older protocols for
interoperability with older server appliances, the additional
complexity of supporting the implicit initialisation vector for
TLSv1.0 is not worth the cost.
Remove support for the obsolete TLSv1.0 protocol, to reduce complexity
of the implementation and simplify ongoing maintenance.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Accept and record the ServerKeyExchange record, which is required for
key exchange mechanisms such as Ephemeral Diffie-Hellman (DHE).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The pre-master secret is currently constructed at the time of
instantiating the TLS connection. This precludes the use of key
exchange mechanisms such as Ephemeral Diffie-Hellman (DHE), which
require a ServerKeyExchange message to exchange additional key
material before the pre-master secret can be constructed.
Allow for the use of such cipher suites by deferring generation of the
master secret until the point of sending the ClientKeyExchange
message.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The master secret is currently constructed upon receiving the
ServerHello message. This precludes the use of key exchange
mechanisms such as Ephemeral Diffie-Hellman (DHE), which require a
ServerKeyExchange message to exchange additional key material before
the pre-master secret and master secret can be constructed.
Allow for the use of such cipher suites by deferring generation of the
master secret until the point of sending the ClientKeyExchange
message.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Simplify the internal HMAC API so that the key is provided only at the
point of calling hmac_init(), and the (potentially reduced) key is
stored as part of the context for later use by hmac_final().
This simplifies the calling code, and avoids the need for callers such
as TLS to allocate a potentially variable length block in order to
retain a copy of the unmodified key.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Experience suggests that routers are often misconfigured to advertise
SLAAC even on prefixes that do not have a SLAAC-compatible prefix
length. iPXE will currently treat this as an error, resulting in the
prefix being ignored completely.
Handle this misconfiguration by ignoring the autonomous address flag
when the prefix length is unsuitable for SLAAC.
Reported-by: Malte Janduda <mail@janduda.net>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We currently define the active DNS server as a global variable. All
queries will start by attempting to contact the active DNS server, and
the active DNS server will be changed only if we fail to get a
response. This effectively treats the DNS server list as expressing a
weak preference ordering: we will try servers in order, but once we
have found a working server we will stick with that server for as long
as it continues to respond to queries.
Some sites are misconfigured to hand out DNS servers that do not have
a consistent worldview. For example: the site may hand out two DNS
server addresses, the first being an internal DNS server (which is
able to resolve names in private DNS domains) and the second being a
public DNS server such as 8.8.8.8 (which will correctly return
NXDOMAIN for any private DNS domains). This type of configuration is
fundamentally broken and should never be used, since any DNS resolver
performing a query for a name within a private DNS domain may obtain a
spurious NXDOMAIN response for a valid private DNS name.
Work around these broken configurations by treating the DNS server
list as expressing a strong preference ordering, and always starting
DNS queries from the first server in the list (rather than maintaining
a global concept of the active server). This will have the debatable
benefit of converting permanent spurious NXDOMAIN errors into
transient spurious NXDOMAIN errors, which can at least be worked
around at a higher level (e.g. by retrying a download in a loop within
an iPXE script).
The cost of always starting DNS queries from the first server in the
list is a slight delay introduced when the first server is genuinely
unavailable. This should be negligible in practice since DNS queries
are relatively infrequent and the failover expiry time is short.
Treating the DNS server list as a preference ordering is permitted by
the language of RFC 2132, which defines DHCP option 6 as a list in
which "[DNS] servers SHOULD be listed in order of preference". No
specification defines a precise algorithm for how this preference
order should be applied in practice: this new approach seems as good
as any.
Requested-by: Andreas Hammarskjöld <junior@2PintSoftware.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown
Cornelius Hoffmann