Created attachment 159563 [details] Initialize environment using argv[] Hi, As discussed here on -hackers@ : https://lists.freebsd.org/pipermail/freebsd-hackers/2015-August/048071.html and for the record, here are two simple patches that allows the EFI loader to set environment variables from arguments and locally override the root path offered through BOOTP (through a new variable called "dhcp.root-path.override"). This allows to chainload loader.efi and pass your root-path (and any other variable) this way (e.g. with iPXE) : #!ipxe chain http://path.to/loader.efi dhcp.root-path.override=server_ip:/path/to/root some_other_var=value Those patches are quite basic and will probably need refactoring, but you get the idea :p Regards, Ganael.
Created attachment 159564 [details] Use dhcp.root-path.override to override BOOTP root path
Finally got around to doing something with this, sorry for the long delay. I took the attached patch and reworked it so that any value delivered from the server that gets automatically set into the dhcp.* env vars can now be overridden with values the platform-specific part of loader(8) has preloaded into the environment. The rootpath and hostname global vars used by other networking code in libstand will be overridden in addition to the automatic dhcp.* vars. I also took the patch from the mailing list thread that sets env vars from the efi loader command line and prepared it for commit. The patches have been turned into a pair of phabricator reviews: https://reviews.freebsd.org/D4559 https://reviews.freebsd.org/D4561
A commit references this bug: Author: ian Date: Tue Dec 22 03:02:52 UTC 2015 New revision: 292583 URL: https://svnweb.freebsd.org/changeset/base/292583 Log: Allow dhcp/bootp server-provided values to be overriden from environment variables in loader(8) and other libstand applications. Sometimes a dhcp server provides incorrect information along with the IP address. It would be useful to have a way to override this with locally-supplied information, such as command line parameters passed from a prior-stage bootloader. This change allows pre-existing env vars to take precedence over values delivered by the dhcp or bootp server. The bootp/dhcp code in libstand automatically creates environment variables from the data provided by the server (dhcp.root-path, dhcp.domain-name, etc). It also transcribes the values to some global variables such as 'rootpath' and 'hostname'. This change does two things: When adding dhcp.* vars to the environment, don't replace existing vars/values. When setting the global vars rootpath and hostname, use the dhcp.root-path and dhcp.host-name env var values if they exist. This allows the platform-specific part of loader(8) to obtain override values in some platform-specific way and store them in the environment before opening the network device. The set of values that can be overriden is currently limited to just string options. The values that are delivered as binary data are things that probably shouldn't be overridden (IP, netmask, gateway, etc). The original patch this evolved from was submitted by martymac@ PR: 202098 Differential Revision: https://reviews.freebsd.org/D4559 Changes: head/lib/libstand/bootp.c
A commit references this bug: Author: ian Date: Tue Dec 22 03:07:38 UTC 2015 New revision: 292584 URL: https://svnweb.freebsd.org/changeset/base/292584 Log: Set env vars from values on the efi loader command line. Examine each cmdline arg and if it contains an '=' convert it to ascii and pass it to putenv(). This allows var=value settings to come in on the command line. This will allow overriding dhcp server-provided data in loader(8), as discussed in PR 202098 PR: 202098 Differential Revision: https://reviews.freebsd.org/D4561 Changes: head/sys/boot/efi/loader/main.c
A commit references this bug: Author: ian Date: Tue Jan 19 21:35:10 UTC 2016 New revision: 294343 URL: https://svnweb.freebsd.org/changeset/base/294343 Log: MFC r292583: Allow dhcp/bootp server-provided values to be overriden from environment variables in loader(8) and other libstand applications. Sometimes a dhcp server provides incorrect information along with the IP address. It would be useful to have a way to override this with locally-supplied information, such as command line parameters passed from a prior-stage bootloader. This change allows pre-existing env vars to take precedence over values delivered by the dhcp or bootp server. The bootp/dhcp code in libstand automatically creates environment variables from the data provided by the server (dhcp.root-path, dhcp.domain-name, etc). It also transcribes the values to some global variables such as 'rootpath' and 'hostname'. This change does two things: When adding dhcp.* vars to the environment, don't replace existing vars/values. When setting the global vars rootpath and hostname, use the dhcp.root-path and dhcp.host-name env var values if they exist. This allows the platform-specific part of loader(8) to obtain override values in some platform-specific way and store them in the environment before opening the network device. The set of values that can be overriden is currently limited to just string options. The values that are delivered as binary data are things that probably shouldn't be overridden (IP, netmask, gateway, etc). The original patch this evolved from was submitted by martymac@ PR: 202098 Relnotes: Yes Changes: _U stable/10/ stable/10/lib/libstand/bootp.c
A commit references this bug: Author: ian Date: Tue Jan 19 21:39:22 UTC 2016 New revision: 294345 URL: https://svnweb.freebsd.org/changeset/base/294345 Log: MFC r292584: Set env vars from values on the efi loader command line. Examine each cmdline arg and if it contains an '=' convert it to ascii and pass it to putenv(). This allows var=value settings to come in on the command line. This will allow overriding dhcp server-provided data in loader(8), as discussed in PR 202098 PR: 202098 Relnotes: Yes (this goes together with r294343) Changes: _U stable/10/ stable/10/sys/boot/efi/loader/main.c
Fixed committed, MFC'd to 10-stable. Efi loader code doesn't appear to exist in 9-stable.