[dhcp] Copy exactly the required length when resizing DHCP options
When resizing DHCP options, iPXE currently calculates the length to be
copied by subtracting the destination pointer from the end of buffer
pointer. This works and guarantees not to write beyond the end of the
buffer, but may end up reading beyond the end of the buffer.
Fix by calculating the required length exactly.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[settings] Formalise notion of setting applicability
Expose a function setting_applies() to allow a caller to determine
whether or not a particular setting is applicable to a particular
settings block.
Restrict DHCP-backed settings blocks to accepting only DHCP-based
settings.
Restrict network device settings blocks to accepting only DHCP-based
settings and network device-specific settings such as "mac".
Inspired-by: Glenn Brown <glenn@myri.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[dhcp] Allow use of custom reallocation functions for DHCP option blocks
Allow functions other than realloc() to be used to reallocate DHCP
option block data, and specify the reallocation function at the time
of calling dhcpopt_init().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
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resources has been revoked by the registrant of the domain.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>
Change the behaviour for adding DHCP options into a DHCP packet so
that we now append options, rather than insert them in front of
whatever options might already be present.
Apparently, the DHCP relay logic on a Nortel 470-48T layer 2 switch
cares about the order of DHCP options. If we build a DHCP packet
pre-populated with some options, their order will now be preserved,
except for encapsulated options.
Signed-off-by: Marty Connor <mdc@etherboot.org>
[Settings] Remove assumption that all settings have DHCP tag values
Allow for settings to be described by something other than a DHCP option
tag if desirable. Currently used only for the MAC address setting.
Separate out fake DHCP packet creation code from dhcp.c to fakedhcp.c.
Remove notion of settings from dhcppkt.c.
Rationalise dhcp.c to use settings API only for final registration of the
DHCP options, rather than using {store,fetch}_setting throughout.
Allow for calling find_dhcp_option() with "options" set to NULL, in order
to search through all registered option blocks.
Move some static inlines that are likely to be used frequently into
dhcpopts.c as normal functions, to save space.
Add sketch code to reassemble a DHCP packet from our internal "everything
is a DHCP option" data structures.
We need this code in order to be able to return a DHCP packet to a PXE NBP
which reflects options from our multiple sources (e.g. NVS and DHCP
server). This is expensive, but necessary. Having paid this cost, we may
as well try to use the same code to generate our DHCP request packets,
since the process is similar.
Michael Brown