[pve-devel] [PATCH installer v2] auto: allow a binary executable as the first boot executable

[Christoph Heiss]

LGTM. Tested with a shell script and a compiled binary, w/ and w/o
sending the `Content-Length` header in the response.

The "Automated Installation" page needs to be updated though, to
reflect:

a) that either shell-scripts or compiled binaries can be used and
b) that the compiled binaries must be (obviously) x86_64 and best case
   statically linked, as there otherwise no guarantees that it will run
   on the target system and might just fail blindly.

Please consider this patch:

Tested-by: Christoph Heiss <c.heiss at proxmox.com>
Reviewed-by: Christoph Heiss <c.heiss at proxmox.com>

FWIW, just thinking out loud here: Maybe the fetching of the first-boot
hook should be moved into `proxmox-fetch-answer` altogether. In a sense
that `proxmox-fetch-answer` would fetch all the needed things in
advance, such that the auto-installer, post-hook etc. doesn't have to do
that anymore.
But that's really not pressing of any kind, rather a long-term thing.

On Wed Dec 11, 2024 at 10:24 AM CET, Daniel Kral wrote:
> As the initial use case for the first boot feature request [0] was for
> running shell scripts, the auto installer retrieved the binary as a
> `String`. Unfortunately, this tries to interpret binary data as UTF-8
> and will transform 'invalid' characters to replacement characters [1].
>
> This causes the auto-installer to create an invalid binary when fetching
> from an URL, and error with a `stream did not contain valid UTF-8` error
> when fetching from the ISO image.
>
> To allow binary executables to be used as a first boot executable, this
> commit changes the fetching from being read as a `String` to being read
> as a `Vec<u8>` to not interfere with the content of the executable.
>
> [0] https://bugzilla.proxmox.com/show_bug.cgi?id=5579
> [1] https://doc.rust-lang.org/src/alloc/string.rs.html#635
>
> Signed-off-by: Daniel Kral <d.kral at proxmox.com>
> ---
> changes from v1:
>   - remove explicit handling of `std::io::ErrorKind::UnexpectedEof`
>
>  .../src/bin/proxmox-auto-installer.rs          | 12 ++++++++----
>  proxmox-installer-common/src/http.rs           | 18 ++++++++++++++----
>  2 files changed, 22 insertions(+), 8 deletions(-)
> [..]