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* [ipv4] Accept unicast packets for the local network broadcast addressMichael Brown2017-01-221-0/+1
| | | | | | | | | | | | | The ISC Kea DHCP server transmits its DHCPOFFER as a unicast packet with a broadcast IPv4 destination address (255.255.255.255). This combination is currently rejected by iPXE. Fix by explicitly accepting the local network broadcast address (255.255.255.255) as a valid unicast destination address. Reported-by: Roy Ledochowski <roy.ledochowski@hpe.com> Tested-by: Roy Ledochowski <roy.ledochowski@hpe.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [settings] Create space for IPv6 in settings display orderMichael Brown2016-07-151-3/+3
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Send gratuitous ARPs whenever a new IPv4 address is appliedMichael Brown2016-07-121-20/+80
| | | | | | | | | | | | | | | | | | | | In a busy network (such as a public cloud), IPv4 addresses may be recycled rapidly. When this happens, unidirectional traffic (such as UDP syslog) will succeed, but bidirectional traffic (such as TCP connections) may fail due to stale ARP cache entries on other nodes. The remote ARP cache expiry timeout is likely to exceed iPXE's connection timeout, meaning that boot attempts can fail before the problem is automatically resolved. Fix by sending gratuitous ARPs whenever an IPv4 address is changed, to attempt to update stale remote ARP cache entries. Note that this is not a guaranteed fix, since ARP is an unreliable protocol. We avoid sending gratuitous ARPs unconditionally, since otherwise any unrelated settings change (e.g. "set dns 192.168.0.1") would cause unexpected gratuitous ARPs to be sent. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [tcpip] Avoid generating positive zero for transmitted UDP checksumsMichael Brown2015-09-101-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TCP/IP checksum fields are one's complement values and therefore have two possible representations of zero: positive zero (0x0000) and negative zero (0xffff). In RFC768, UDP over IPv4 exploits this redundancy to repurpose the positive representation of zero (0x0000) to mean "no checksum calculated"; checksums are optional for UDP over IPv4. In RFC2460, checksums are made mandatory for UDP over IPv4. The wording of the RFC is such that the UDP header is mandated to use only the negative representation of zero (0xffff), rather than simply requiring the checksum to be correct but allowing for either representation of zero to be used. In RFC1071, an example algorithm is given for calculating the TCP/IP checksum. This algorithm happens to produce only the positive representation of zero (0x0000); this is an artifact of the way that unsigned arithmetic is used to calculate a signed one's complement sum (and its final negation). A common misconception has developed (exemplified in RFC1624) that this artifact is part of the specification. Many people have assumed that the checksum field should never contain the negative representation of zero (0xffff). A sensible receiver will calculate the checksum over the whole packet and verify that the result is zero (in whichever representation of zero happens to be generated by the receiver's algorithm). Such a receiver will not care which representation of zero happens to be used in the checksum field. However, there are receivers in existence which will verify the received checksum the hard way: by calculating the checksum over the remainder of the packet and comparing the result against the checksum field. If the representation of zero used by the receiver's algorithm does not match the representation of zero used by the transmitter (and so placed in the checksum field), and if the receiver does not explicitly allow for both representations to compare as equal, then the receiver may reject packets with a valid checksum. For UDP, the combined RFCs effectively mandate that we should generate only the negative representation of zero in the checksum field. For IP, TCP and ICMP, the RFCs do not mandate which representation of zero should be used, but the misconceptions which have grown up around RFC1071 and RFC1624 suggest that it would be least surprising to generate only the positive representation of zero in the checksum field. Fix by ensuring that all of our checksum algorithms generate only the positive representation of zero, and explicitly inverting this in the case of transmitted UDP packets. Reported-by: Wissam Shoukair <wissams@mellanox.com> Tested-by: Wissam Shoukair <wissams@mellanox.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [tcpip] Allow supported address families to be detected at runtimeMichael Brown2015-09-011-0/+1
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Allow IPv4 socket addresses to include a scope IDMichael Brown2015-07-281-12/+33
| | | | | | | | | | | | Extend the IPv6 concept of "scope ID" (indicating the network device index) to IPv4 socket addresses, so that IPv4 multicast transmissions may specify the transmitting network device. The scope ID is not (currently) exposed via the string representation of the socket address, since IPv4 does not use the IPv6 concept of link-local addresses (which could legitimately be specified in a URI). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Redefine IP address constants to avoid unnecessary byte swappingMichael Brown2015-07-281-8/+8
| | | | | | | | Redefine various IPv4 address constants and testing macros to avoid unnecessary byte swapping at runtime, and slightly rename the macros to prevent code from accidentally using the old definitions. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Fix the REQUIRE_SYMBOL mechanismMichael Brown2015-03-051-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | At some point in the past few years, binutils became more aggressive at removing unused symbols. To function as a symbol requirement, a relocation record must now be in a section marked with @progbits and must not be in a section which gets discarded during the link (either via --gc-sections or via /DISCARD/). Update REQUIRE_SYMBOL() to generate relocation records meeting these criteria. To minimise the impact upon the final binary size, we use existing symbols (specified via the REQUIRING_SYMBOL() macro) as the relocation targets where possible. We use R_386_NONE or R_X86_64_NONE relocation types to prevent any actual unwanted relocation taking place. Where no suitable symbol exists for REQUIRING_SYMBOL() (such as in config.c), the macro PROVIDE_REQUIRING_SYMBOL() can be used to generate a one-byte-long symbol to act as the relocation target. If there are versions of binutils for which this approach fails, then the fallback will probably involve killing off REQUEST_SYMBOL(), redefining REQUIRE_SYMBOL() to use the current definition of REQUEST_SYMBOL(), and postprocessing the linked ELF file with something along the lines of "nm -u | wc -l" to check that there are no undefined symbols remaining. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [legal] Relicense files under GPL2_OR_LATER_OR_UBDLMichael Brown2015-03-021-1/+5
| | | | | | | | | | These files cannot be automatically relicensed by util/relicense.pl since they either contain unusual but trivial contributions (such as the addition of __nonnull function attributes), or contain lines dating back to the initial git revision (and so require manual knowledge of the code's origin). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Rewrite inet_aton()Michael Brown2015-02-191-5/+37
| | | | | | | | | | The implementation of inet_aton() has an unknown provenance. Rewrite this code to avoid potential licensing uncertainty. Also move the code from core/misc.c to its logical home in net/ipv4.c, and add a few extra test cases. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [legal] Add missing copyright header to net/ipv4.cMichael Brown2015-02-181-0/+20
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Profile transmit and receive datapathsMichael Brown2014-04-281-0/+15
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [tcpip] Provide tcpip_mtu() to determine the maximum transmission unitMichael Brown2014-03-041-0/+1
| | | | | | | | Provide the function tcpip_mtu() to allow external code to determine the (transport-layer) maximum transmission unit for a given socket address. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [tcpip] Provide tcpip_netdev() to determine the transmitting network deviceMichael Brown2014-03-041-0/+20
| | | | | | | Provide the function tcpip_netdev() to allow external code to determine the transmitting network device for a given socket address. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [tcpip] Add IP statistics collection as per RFC 4293Michael Brown2014-03-021-10/+45
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [settings] Merge SETTING_IPv4 and SETTING_IPv6Michael Brown2013-12-051-3/+3
| | | | | | | Allow for equivalent IPv4 and IPv6 settings (which requires equivalent settings to be adjacent within the settings list). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [settings] Force settings into alphabetical order within sectionsMichael Brown2013-12-051-3/+3
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [settings] Allow for IPv6 setting types in non-IPv6 buildsMichael Brown2013-12-051-0/+45
| | | | | | | | | Allow for the existence of references to IPv6 setting types without dragging in the whole IPv6 stack, by placing the definition of setting_type_ipv6 in core/settings.c and providing weak stub methods for parse_ipv6_setting() and format_ipv6_setting(). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [settings] Explicitly separate the concept of a completed fetched settingMichael Brown2013-12-051-3/+3
| | | | | | | | | | The fetch_setting() family of functions may currently modify the definition of the specified setting (e.g. to add missing type information). Clean up this interface by requiring callers to provide an explicit buffer to contain the completed definition of the fetched setting, if required. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [icmp] Add support for sending ICMP echo requestsMichael Brown2013-10-211-2/+2
| | | | | | | | Merge common functionality between IPv4 and IPv6 ICMP echo handling, and add support for transmitting ICMP echo requests and delivering ICMP echo replies to a (not yet implemented) ping_rx() function. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Add IPv4 socket address converterMichael Brown2013-10-211-0/+37
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv6] Replace IPv6 stackMichael Brown2013-09-031-1/+1
| | | | | | | | | | | | | | | | Replace the existing partially-implemented IPv6 stack with a fresh implementation. This implementation is not yet complete. The IPv6 transmit and receive datapaths are functional (including fragment reassembly and parsing of arbitrary extension headers). NDP neighbour solicitations and advertisements are supported. ICMPv6 echo is supported. At present, only link-local addresses may be used, and there is no way to specify an IPv6 address as part of a URI (either directly or via a DNS lookup). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [tcpip] Pass through network device to transport layer protocolsMichael Brown2013-09-031-1/+1
| | | | | | | NDP requires knowledge of the network device on which a packet was received. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Generalise fragment reassembly mechanismMichael Brown2013-08-271-117/+39Star
| | | | | | | Generalise the concept of fragment reassembly to allow for code sharing between IPv4 and IPv6 protocols. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [dhcp] Request broadcast responses when we already have an IPv4 addressMichael Brown2012-06-201-1/+1
| | | | | | | | | | | | | | | | | FCoE requires the use of multiple local unicast link-layer addresses. To avoid the complexity of managing multiple addresses, iPXE operates in promiscuous mode. As a consequence, any unicast packets with non-matching IPv4 addresses are rejected at the IPv4 layer (rather than at the link layer). This can cause problems when issuing a second DHCP request: if the address chosen by the DHCP server does not match the existing address, then the DHCP response will itself be rejected. Fix by requesting a broadcast response from the DHCP server if the network interface already has any IPv4 addresses. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [arp] Maintain an ARP transmission queueMichael Brown2012-03-031-46/+38Star
| | | | | | | | Allow packet transmission to be deferred pending successful ARP resolution. This avoids the time spent waiting for a higher-level protocol (e.g. TCP or TFTP) to attempt retransmission. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Improve debuggingMichael Brown2011-07-161-45/+51
| | | | | | | Use autocolourisation to improve legibility, and move per-packet messages to DBG2(). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Fix fragment reassemblyMichael Brown2011-07-161-92/+120
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Use broadcast link-layer address for all broadcast IPv4 addressesMichael Brown2011-07-151-7/+7
| | | | | | | | When transmitting, use the broadcast link-layer address for any broadcast address (e.g. 192.168.0.255), not just INADDR_BROADCAST (255.255.255.255). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Discard unwanted unicast packetsMichael Brown2011-07-151-10/+50
| | | | | | | | Explicitly discard any unicast packets for addresses that we do not control, to avoid unexpected behaviour when operating in promiscuous mode (which is now the default, thanks to FCoE). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [netdevice] Allow link layer to report broadcast/multicast packets via pull()Michael Brown2011-07-151-5/+8
| | | | | | | | Allow the link layer to directly report whether or not a packet is multicast or broadcast at the time of calling pull(), rather than relying on heuristics to determine this at a later stage. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Record ARP resolution errorsMichael Brown2011-06-281-0/+2
| | | | | | | | | At the time of attempting ARP resolution, we already know the transmitting network device. We can therefore record ARP errors using netdev_tx_err() so that they show up in the output of "ifstat". Inspired-by: Dominik Russenberger <dominik.russenberger@terreactive.ch> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [ipv4] Include network device metadata in packet tracesMichael Brown2011-05-051-3/+10
| | | | | | | | | | | | | | | | | (Ab)use the "ident" field in transmitted IPv4 packets to convey metadata about the network device. In particular: bits 0-3 represent the low bits of the "RX" good packet counter bits 4-7 represent the low bits of the "RXE" bad packet counter bits 8-15 represent the transmitted packet sequence number This allows some relevant information about the internal state of the network device to be read out from a packet trace from a non-debug build of iPXE. In particular, it allows a packet trace containing packets transmitted by iPXE to indicate whether or not any packets have been received by iPXE. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [settings] Match terminology in online documentationMichael Brown2011-03-231-2/+2
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [settings] Impose a fixed order on settingsMichael Brown2011-03-231-3/+3
| | | | | | | Improve the appearance of the "config" user interface by ensuring that settings appear in some kind of logical order. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [netdevice] Pass both link-layer addresses in net_tx() and net_rx()Michael Brown2010-10-071-2/+6
| | | | | | | | | FCoE requires the use of fabric-provided MAC addresses, which breaks the assumption that the net device's MAC address is implicitly the source address for net_tx() and the (unicast) destination address for net_rx(). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [retry] Hold reference while timer is running and during expiry callbackMichael Brown2010-09-031-1/+1
| | | | | | | | | Guarantee that a retry timer cannot go out of scope while the timer is running, and provide a guarantee to the expiry callback that the timer will remain in scope during the entire callback (similar to the guarantee provided to interface methods). Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Fix misaligned table entries when using gcc 4.5Piotr Jaroszyński2010-08-201-2/+0Star
| | | | | | | | | | Declarations without the accompanying __table_entry cause misalignment of the table entries when using gcc 4.5. Fix by adding the appropriate __table_entry macro or (where possible) by removing unnecessary forward declarations. Signed-off-by: Piotr Jaroszyński <p.jaroszynski@gmail.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [retry] Use start_timer_fixed() instead of direct timeout manipulationMichael Brown2010-06-221-2/+1Star
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [retry] Add timer_init() wrapper functionMichael Brown2010-06-221-1/+1
| | | | | | | Standardise on using timer_init() to initialise an embedded retry timer, to match the coding style used by other embedded objects. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Rename gPXE to iPXEMichael Brown2010-04-201-10/+10
| | | | | | | | | | | Access to the gpxe.org and etherboot.org domains and associated resources has been revoked by the registrant of the domain. Work around this problem by renaming project from gPXE to iPXE, and updating URLs to match. Also update README, LOG and COPYRIGHTS to remove obsolete information. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [netdevice] Add netdev_is_open() wrapper functionMichael Brown2010-03-231-1/+1
| | | | Signed-off-by: Michael Brown <mcb30@etherboot.org>
* [ipv4] Ignore non-open net devices when performing routingMichael Brown2009-11-161-0/+2
| | | | | | | | | We do not discard routing table entries when closing an interface. It is plausible that multiple interfaces may be on the same physical network; if so, then we may end up in a situation whereby outbound packets attempt to route via a closed interface. Fix by ignoring non-open net devices in ipv4_route().
* [ipv4] Allow calculation of default subnet maskMichael Brown2009-11-161-11/+11
| | | | | | | | | | | | | ipv4.c calculates the default subnet mask before calling fetch_ipv4_setting() to retrieve the configured subnet mask (if any). However, as of commit 612f4e7 "[settings] Avoid returning uninitialised data on error in fetch_xxx_setting()", fetch_ipv4_setting() will zero the IP address if the setting does not exist, rather than leaving it unaltered. Fix by fetching the setting first and calculating the default subnet mask only if necessary.
* [ipv4] Use a zero address to indicate "no gateway", rather than INADDR_NONEMichael Brown2009-11-161-7/+6Star
| | | | | | | | | | | | | | | ipv4.c uses a gateway address of INADDR_NONE to represent "no gateway". It initialises the gateway address to INADDR_NONE before calling fetch_ipv4_setting() to retrieve the configured gateway address (if any). However, as of commit 612f4e7 "[settings] Avoid returning uninitialised data on error in fetch_xxx_setting()", fetch_ipv4_setting() will zero the IP address if the setting does not exist, rather than leaving it unaltered. Fix by using a zero IP address to indicate "no gateway", so that a non-existent gateway address setting will be treated as such.
* [netdevice] Make ll_broadcast per-netdevice rather than per-ll_protocolMichael Brown2009-07-181-1/+1
| | | | | | | | | IPoIB has a link-layer broadcast address that varies according to the partition key. We currently go through several contortions to pretend that the link-layer address is a fixed constant; by making the broadcast address a property of the network device rather than the link-layer protocol it will be possible to simplify IPoIB's broadcast handling.
* [legal] Add a selection of FILE_LICENCE declarationsMichael Brown2009-05-181-0/+2
| | | | | Add FILE_LICENCE declarations to almost all files that make up the various standard builds of gPXE.
* [icmp] Add support for responding to pingsMichael Brown2009-02-171-0/+3
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* [tcpip] Allow for transmission to multicast IPv4 addressesMichael Brown2009-01-211-1/+8
| | | | | | | | | | | When sending to a multicast address, it may be necessary to specify the source address explicitly, since the multicast destination address does not provide enough information to deduce the source address via the miniroute table. Allow the source address specified via the data-xfer metadata to be passed down through the TCP/IP stack to the IPv4 layer, which can use it as a default source address.
* [build] Keep gcc 4.4 happyMichael Brown2008-11-181-1/+1
| | | | | gcc 4.4 adds another few warnings, and also seems to complain if we place %ebp in the clobber list for any inline asm.
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