Most image flags are independent values: any combination of flags may
be set for any image, and the flags for one image are independent of
the flags for any other image. The "selected" flag does not follow
this pattern: at most one image may be marked as selected at any time.
When invoking a kernel via the UEFI shim, there will be multiple
"special" images: the selected kernel itself, the shim image, and
potentially a shim-signed GRUB binary to be used as a crutch to assist
shim in loading the kernel (since current versions of the UEFI shim
are not capable of directly loading a Linux kernel).
Remove the "selected" image flag and replace it with a general concept
of an image tag with the same semantics: a given tag may be assigned
to at most one image, an image may be found by its tag only while the
image is currently registered, and a tag will survive unregistration
and reregistration of an image (if it has not already been assigned to
a new image). For visual consistency, also replace the current image
pointer with a current image tag.
The image pointer stored within the image tag holds only a weak
reference to the image, since the selection of an image should not
prevent that image from being freed. (The strong reference to the
currently executing image is held locally within the execution scope
of image_exec(), and is logically separate from the current image
pointer.)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We unregister script images during their execution, to prevent a
"boot" command from re-executing the containing script. This also has
the side effect of preventing executing scripts from showing up within
the Linux magic initrd image (or the Multiboot module list).
Additional logic in bzimage.c and efi_file.c prevents a currently
executing kernel from showing up within the magic initrd image.
Similar logic in multiboot.c prevents the Multiboot kernel from
showing up as a Multiboot module.
This still leaves some corner cases that are not covered correctly.
For example: when using a gzip-compressed kernel image, nothing will
currently hide the original compressed image from the magic initrd.
Fix by moving the logic that temporarily unregisters the current image
from script_exec() to image_exec(), so that it applies to all image
types, and simplify the magic initrd and Multiboot module list
construction logic on the basis that no further filtering of the
registered image list is necessary.
This change has the side effect of hiding currently executing EFI
images from the virtual filesystem exposed by iPXE. For example, when
using iPXE to boot wimboot, the wimboot binary itself will no longer
be visible within the virtual filesystem.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The Linux kernel bzImage image format and the CPIO archive constructor
will parse the image command line for certain arguments of the form
"key=value". This parsing is currently implemented using strstr() in
a way that can cause a false positive suffix match. For example, a
command line containing "highmem=<n>" would erroneously be treated as
containing a value for "mem=<n>".
Fix by centralising the logic used for parsing such arguments, and
including a check that the argument immediately follows a whitespace
delimiter (or is at the start of the string).
Reported-by: Filippo Giunchedi <filippo@esaurito.net>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Embedded images do not have an associated URI. This currently causes
the current working URI (cwuri) to be cleared when starting an
embedded image.
If the current working URI has been set via a ${next-server} setting
from a cached DHCP packet then this will result in unexpected
behaviour. An attempt by the embedded script to use a relative URI to
download files from the TFTP server will fail with the error:
Could not start download: Operation not supported (ipxe.org/3c092083)
Rerunning the "dhcp" command will not fix this error, since the TFTP
settings applicator will not see any change to the ${next-server}
setting and so will not reset the current working URI.
Fix by setting the current working URI to the image's URI only if the
image actually has an associated URI.
Debugged-by: Ignat Korchagin <ignat@cloudflare.com>
Originally-fixed-by: Ignat Korchagin <ignat@cloudflare.com>
Tested-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Consolidate the remaining logic common to initrd_init() and imgmem()
into a shared image_memory() function.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Enable IMAGE_PNG (but not IMAGE_PNM) by default, and drag in the
relevant objects only when image_pixbuf() is present in the binary.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Enable both IMAGE_DER and IMAGE_PEM by default, and drag in the
relevant objects only when image_asn1() is present in the binary.
This allows "imgverify" to transparently use either DER or PEM
signature files.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Return success (rather than failure) after an image format has been
correctly identified.
This has no practical effect, since the return value from
image_probe() is deliberately never used, but avoids a somewhat
surprising and misleading "format not recognised" error message when
debugging is enabled.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The current usage pattern of image_probe() is a legacy from the time
before commit 34b6ecb ("[image] Simplify image management") when
loading an image to its executable location in memory was a separate
action from actually executing the image.
Call image_probe() as soon as an image is registered. This allows
"imgstat" to display image type information for all images and allows
image-consuming code to assume that image->type is already set
correctly.
Ignore failures if image_probe() does not recognise the image, since
we do expect to handle unrecognised images (initrds, modules, etc).
Unrecognised images will be left with a NULL image->type, which
image-consuming code can easily check.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
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>
Expose image tail-recursion to iPXE scripts via the "--replace"
option. This functions similarly to exec() under Unix: the
currently-executing script is replaced with the new image (as opposed
to running the new image as a subroutine).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Remove the name, cmdline, and action parameters from imgdownload() and
imgdownload_string(). These functions now simply download and return
an image.
Add the function imgacquire(), which will interpret a "name or URI
string" parameter and return either an existing image or a newly
downloaded image.
Use imgacquire() to merge similar image-management commands that
currently differ only by whether they take the name of an existing
image or the URI of a new image to download. For example, "chain" and
"imgexec" can now be merged.
Extend imgstat and imgfree commands to take an optional list of
images.
Remove the arbitrary restriction on the length of image names.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Trusted images may always be executed. Untrusted images may be
executed only if the current image trust requirement allows untrusted
images.
Images can be marked as trusted using image_trust(), and marked as
untrusted using image_untrust().
The current image trust requirement can be changed using
image_set_trust(). It is possible to make the change permanent, in
which case any future attempts to change the image trust requirement
will fail.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
All users of imgdownload() require registration of the image, so make
registration an integral part of imgdownload() itself and simplify the
"action" parameter to be one of image_select(), image_exec() et al.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
These functions are used only as the "action" parameters to
imgdownload() or imgfetch(), and so belong in imgmgmt.c rather than
image.c
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Refactor the {load,exec} image operations as {probe,exec}. This makes
the probe mechanism cleaner, eliminates some forward declarations,
avoids holding magic state in image->priv, eliminates the possibility
of screwing up between the "load" and "exec" stages, and makes the
documentation simpler since the concept of "loading" (as distinct from
"executing") no longer needs to be explained.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
image_set_cmdline() strdup()s cmdline, which free_image() doesn't
clean up.
Signed-off-by: Piotr Jaroszyński <p.jaroszynski@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Standardise on using ref_init() to initialise an embedded reference
count, to match the coding style used by other embedded objects.
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>
Intel's C compiler (icc) chokes on the zero-length arrays that we
currently use as part of the mechanism for accessing linker table
entries. Abstract away the zero-length arrays, to make a port to icc
easier.
Introduce macros such as for_each_table_entry() to simplify the common
case of iterating over all entries in a linker table.
Represent table names as #defined string constants rather than
unquoted literals; this avoids visual confusion between table names
and C variable or type names, and also allows us to force a
compilation error in the event of incorrect table names.
Multi-level menus via COMBOOT rely on the COMBOOT program being able
to exit and invoke a new COMBOOT program (the next menu). This works,
but rapidly (within about five iterations) runs out of space in gPXE's
internal stack, since each new image is executed in a new function
context.
Fix by allowing tail recursion between images; an image can now
specify a replacement image for itself, and image_exec() will perform
the necessary tail recursion.
Clearing the LOADED flag actually prevents users from doing clever things
such as loading an image, then loading a patch image, then executing the
first image. (image_exec() checks for IMAGE_LOADED, so this sequence of
operations will fail if the LOADED flag gets cleared.)
This reverts commit 14c080020f.
Loading an image may overwrite part or all of any previously-loaded
images, so we should clear the LOADED flag for all images prior to
attempting to load a new image.
Michael Brown
Piotr Jaroszyński
Michael Brown
Holger Lubitz