[pve-devel] [PATCH pve-storage] fix #6450: add file-checksum endpoint to storage API

[Shannon Sterz]

one comment in-line

On Mon Sep 29, 2025 at 11:35 AM CEST, Nicolas Frey wrote:
> The storage API endpoint now supports an optional 'checksum' parameter.
> If set, the checksum is calculated using one of the hashing algorithms
> listed in the enum and returned in the 'checksum' return property.
>
> Fixes: https://bugzilla.proxmox.com/show_bug.cgi?id=6450
>
> Signed-off-by: Nicolas Frey <n.frey at proxmox.com>
> ---
>  src/PVE/API2/Storage/Content.pm | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
>
> diff --git a/src/PVE/API2/Storage/Content.pm b/src/PVE/API2/Storage/Content.pm
> index 1fe7303..ea60589 100644
> --- a/src/PVE/API2/Storage/Content.pm
> +++ b/src/PVE/API2/Storage/Content.pm
> @@ -306,6 +306,12 @@ __PACKAGE__->register_method({
>                  description => "Volume identifier",
>                  type => 'string',
>              },
> +            checksum => {
> +                description => 'The algorithm to calculate the checksum of the file.',
> +                enum => [qw(sha512 sha384 sha256 sha224 sha1 md5)],
> +                type => 'string',
> +                optional => 1,
> +            }
>          },
>      },
>      returns => {
> @@ -340,6 +346,11 @@ __PACKAGE__->register_method({
>                  type => 'boolean',
>                  optional => 1,
>              },
> +            checksum => {
> +                description => 'The checksum of the file.',
> +                type => 'string',
> +                optional => 1,
> +            }
>          },
>      },
>      code => sub {
> @@ -376,6 +387,11 @@ __PACKAGE__->register_method({
>              warn $@ if $@;
>          }
>
> +        if (exists $param->{checksum}) {
> +            print "calculating checksum...\n";
> +            $entry->{checksum} = PVE::Tools::get_file_hash($param->{checksum}, $path);

i've tested this with some not too uncommon disk images such as a 32GB
volume that is essentially empty and the api endpoint here just times
out. which is not too surprising. i wonder if we can cache the hashes
here somehow and calculate them in a worker tasks. i also wonder how
this should ideally work for running vm and container images as their
checksum could change all the time.

maybe we can at least calculate the hashes here for some more static
assets such iso etc. ahead of time and only enable this flag for things
like that (so isos, container templates, images of vm and container
templates etc.) basically things that don't change that much?

> +        }
> +
>          return $entry;
>      },
>  });