ixbin: Add util script to update image contents

[wkz]

Description

usage: ixbin COMMAND [ARGS...]

Update contents of Infix images

Commands:

  unpack PKG KEY-DIR DIR

    Unpack the RAUC bundle PKG and the root filesystem contained in
    it, using the keys stored in KEY-DIR, and store the results in
    DIR.

  pack DIR [KEY-DIR] PKG

    Repackage the (possibly modified) root filesystem in DIR, updating
    all signatures as necessary using the keys stored in KEY-DIR (or
    the keys used to unpack the bundle, if not specified) and store
    the resulting bundle in PKG.

  exec DIR COMMAND [ARGS...]

    Run COMMAND, possibly with ARGS, from the root of the filesystem
    in DIR, inside of a fakeroot context that allows otherwise
    privileged operations such as ownership modifications.

  help

    Show this message and exit.

Key directories:

  KEY-DIR arguments must reference a directory that contains the
  public/private keypair used to verify/sign an image. Most commonly,
  board/common/signing-keys/development from the Infix source tree is
  used to validate the input image.

Example:

  Include a custom file inside a prebuilt Infix image, assign it to
  the UID/GID 1337; and package up the results, signing it with the
  same developer key that was used to create it:

    ixbin unpack infix-aarch64.pkg ~/infix/board/common/signing-keys/development tmp
    cp VBRUN300.DLL tmp/rootfs/lib/
    ixbin exec tmp chown 1337:1337 lib/VBRUN300.DLL
    ixbin pack tmp infix-vb3-aarch64.pkg

Checklist

Tick relevant boxes, this PR is-a or has-a:

• Bugfix
  • Regression tests
  • ChangeLog updates (for next release)
• Feature
  • YANG model change => revision updated?
  • Regression tests added?
  • ChangeLog updates (for next release)
  • Documentation added?
• Test changes
  • Checked in changed Readme.adoc (make test-spec)
  • Added new test to group Readme.adoc and yaml file
• Code style update (formatting, renaming)
• Refactoring (please detail in commit messages)
• Build related changes
• Documentation content changes
  • ChangeLog updated (for major changes)
• Other (please describe): Utility script

[troglobit]

Very nice work!

[abbenteprizer]

I get error about -s flag for which on Ubuntu 22.

Illegal option -s
Usage: /usr/bin/which [-a] args

Maybe something about the version for which changing between Ubuntu 22 and Ubuntu 24...?

which is mostly just an alias for type with some flags on some distros. I would probably use type here for better portability.

[troglobit]

Good catch! Here's another alternative I often use myself, example from another (POSIX shell compliant) script:

error()
{
    printf "\033[1;31mError: %s\033[0m\n" "$*" >&2
}

fatal()
{
    error "$*"
    exit 1
}

# Check for required programs
for proggy in $DEPS; do
    if ! command -v $proggy >/dev/null 2>&1; then
        fatal "$proggy not found, required."
    fi
done

[wkz]

TIL: which is not in POSIX.

The shame, the absolute SHAME! 😆

Updated the script to use command -v instead.

@abbenteprizer is it working as expected otherwise?