Mostly for cosmetic reasons, we add a "net_dhcp" command, which is (at the
moment) identical to the existing "net_bootp" command. Both actually trigger
a DHCP handshake now, and both should be able to deal with pure BOOTP servers.
We could think about dropping the DHCP options from the initial DISCOVER packet
when the user issues the net_bootp command, but it's unclear whether this is
really useful, as both protocols should be able to coexist.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Even though we were parsing some DHCP options sent by the server, so far
we are only using the BOOTP 2-way handshake, even when talking to a DHCP
server.
Change this by actually sending out DHCP DISCOVER packets instead of the
generic (mostly empty) BOOTP BOOTREQUEST packets.
A pure BOOTP server would ignore the extra DHCP options in the DISCOVER
packet and would just reply with a BOOTREPLY packet, which we also
handle in the code.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
In respone to a BOOTREQUEST packet a BOOTP server would answer with a BOOTREPLY
packet, which ends the conversation for good. DHCP uses a 4-way handshake,
where the initial server respone is an OFFER, which has to be answered with
REQUEST by the client again, only to be completed by an ACKNOWLEDGE packet
from the server.
Teach the grub_net_process_dhcp() function to deal with OFFER packets,
and treat ACK packets the same es BOOTREPLY packets.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The BOOTP RFC describes the boot file name and the server name as being part
of the integral BOOTP data structure, with some limits on the size of them.
DHCP extends this by allowing them to be separate DHCP options, which is more
flexible.
Teach the code dealing with those fields to check for those DHCP options first
and use this information, if provided. We fall back to using the BOOTP
information if those options are not used.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Currently we have a global timeout for all network cards in the BOOTP/DHCP
discovery process.
Make this timeout a per-interface one, so better accommodate the upcoming
4-way DHCP handshake and to also cover the lease time limit a DHCP offer
will come with.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Change the interface of the function dealing with incoming BOOTP packets
to take an interface instead of a card, to allow more fine per-interface
state (timeout, handshake state) later on.
Use the opportunity to clean up the code a bit.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
In contrast to BOOTP, DHCP uses a 4-way handshake, so requires to send
packets more often.
Refactor the generation and sending of the BOOTREQUEST packet into
a separate function, so that future code can more easily reuse this.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
DHCP specifies a special dummy option OVERLOAD, to allow DHCP options to
spill over into the (legacy) BOOTFILE and SNAME fields.
Parse and handle this option properly.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
For proper DHCP support we will need to parse DHCP options from a packet
more often and at various places.
Refactor the option parsing into a new function, which will scan a packet to
find *a particular* option field. Use that new function in places where we
were dealing with DHCP options before.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The comment is right, the "giaddr" fields holds the IP address of the BOOTP
relay, not a general purpose router address. Just remove the commented code,
archeologists can find it in the git history.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Network boot autoconfiguration sets default server to next server IP
(siaddr) from BOOTP/DHCP reply, but manual configuration using net_bootp
exports only server name. Unfortunately semantic of server name is not
clearly defined. BOOTP RFC 951 defines it only for client request, and
DHCP RFC 1541 only mentions it, without any implied usage. It looks like
this field is mostly empty in server replies.
Export next server IP as net_<interface>_next_server variable. This allows
grub configuration script to set $root/$prefix based on information obtained
by net_bootp.
Reported and tested by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Cc: nikunj@linux.vnet.ibm.com
v2: change variable name to net_<interface>_next_server as discussed on the list
send client arch in bootp requests, for now BIOS and x64/aarch64 EFI is
supported.
fix a bug introduced in 4d5d7be005 where
user class was encoded improperly, although this didn't seem to have any
detrimental effects.
properly insert an option terminator.
ipv6 routing in grub2 is broken, we cannot talk to anything outside our local
network or anything that doesn't route in our global namespace. This patch
fixes this by doing a couple of things
1) Read the router information off of the router advertisement. If we have a
router lifetime we need to take the source address and create a route from it.
2) Changes the routing stuff slightly to allow you to specify a gateway _and_ an
interface. Since the router advertisements come in on the link local address we
need to associate it with the global address on the card. So when we are
processing the router advertisement, either use the SLAAC interface we create
and add the route to that interface, or loop through the global addresses we
currently have on our interface and associate it with one of those addresses.
We need to have a special case here for the default route so that it gets used,
we do this by setting the masksize to 0 to mean it encompasses all networks.
The routing code will automatically select the best route so if there is a
closer match we will use that.
With this patch I can now talk to ipv6 addresses outside of my local network.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
It's helpful to determine that a request was sent by grub in order to permit
the server to provide different information at different stages of the boot
process. Send GRUB2 as a type 77 DHCP option when sending bootp packets in
order to make this possible.
From RFC1542:
The 'giaddr' field is rather poorly named. It exists to facilitate
the transfer of BOOTREQUEST messages from a client, through BOOTP
relay agents, to servers on different networks than the client.
Similarly, it facilitates the delivery of BOOTREPLY messages from the
servers, through BOOTP relay agents, back to the client. In no case
does it represent a general IP router to be used by the client. A
BOOTP client MUST set the 'giaddr' field to zero (0.0.0.0) in all
BOOTREQUEST messages it generates.
A BOOTP client MUST NOT interpret the 'giaddr' field of a BOOTREPLY
message to be the IP address of an IP router. A BOOTP client SHOULD
completely ignore the contents of the 'giaddr' field in BOOTREPLY
messages.
Leave code ifdef'd out for the time being in case we see regression.
Suggested by: Rink Springer <rink@rink.nu>
Closes: 43396
Adding multiple questions on a single DNS query is not supportted by
most DNS servers. This patch issues two separate DNS queries
sequentially for ipv4 and then for ipv6.
Fixes: https://savannah.gnu.org/bugs/?39710
* grub-core/net/bootp.c (parse_dhcp_vendor): Add DNS option.
* grub-core/net/dns.c (grub_dns_qtype_id): New enum.
* (grub_net_dns_lookup): Now using separated dns packages.
* (grub_cmd_nslookup): Add error condition.
* (grub_cmd_list_dns): Print DNS option.
* (grub_cmd_add_dns): Add four parameters: --only-ipv4,
* --only-ipv6, --prefer-ipv4, and --prefer-ipv6.
* include/grub/net.h (grub_dns_option_t): New enum.
* (grub_net_network_level_address): option added.
Also-by: Paulo Flabiano Smorigo <pfsmorigo@br.ibm.com>
Signed-off-by: Paulo Flabiano Smorigo <pfsmorigo@br.ibm.com>
* grub-core/net/bootp.c (parse_dhcp_vendor): Parse mask.
(grub_net_configure_by_dhcp_ack): Use mask and grub_net_add_ipv4_local.
* grub-core/net/net.c (grub_net_add_addr): Split creating local route
into ...
(grub_net_add_ipv4_local): ... this.
(grub_cmd_addaddr): Use grub_net_add_ipv4_local.
* include/grub/net.h (GRUB_NET_BOOTP_NETMASK): New enum value.
(grub_net_add_ipv4_local): New proto.
* include/grub/net.h (grub_net_poll_cards): New argument stop_condition.
All users updated.
* grub-core/net/arp.c (have_pending): New var.
(pending_req): Likewise.
(grub_net_arp_send_request): Fill pending_req and use have_pending as
stop indicator.
(grub_net_arp_receive): Set have_pending.
* grub-core/net/dns.c (recv_data): New field stop.
(recv_hook): Set stop.
(grub_net_dns_lookup): Init stop and use as stop condition.
* grub-core/net/http.c (http_establish): Use headers_recv as stop
condition.
* grub-core/net/net.c (grub_net_poll_cards): New argument
stop_condition. Stop when it goes true.
* grub-core/net/tcp.c (grub_net_tcp_open): Use `established' as stop
indicator.
* grub-core/net/tftp.c (tftp_open): Use `have_oack' as stop indicator.
