[pmg-devel] [PATCH pmg-api v4 5/5] fix #2709: ruledb: match-field: optionally restrict to top mime-part

[Dominik Csapak]

an alternative to this could be that we don't traverse entities if they
are a 'message/rfc822' ? that way we could still match fields from
individual parts, just not in nested messages.

But I think this patch is still fine since we document the
match field for mail headers and those (should) only
appear in the top-level part anyway..

On 2/20/25 21:13, Stoiko Ivanov wrote:
> The current Match Field (header) what-objects always traverse each
> mime-part of a mail.
> This can be inconvenient, and causes unexpected matches when you
> forward a message as attachment(message/rfc822).
> 
> following the patches for adding a Disclaimer on top of a mail from an
> implementation point of view, this simply adds an optional
> top-level-only attribute for the MatchField object, which is disabled
> by default for backwards-compatibility.
> 
> Signed-off-by: Stoiko Ivanov <s.ivanov at proxmox.com>
> ---
>   src/PMG/RuleDB/ContentTypeFilter.pm |  2 +-
>   src/PMG/RuleDB/MatchField.pm        | 47 +++++++++++++++++++++++++++--
>   2 files changed, 45 insertions(+), 4 deletions(-)
> 
> diff --git a/src/PMG/RuleDB/ContentTypeFilter.pm b/src/PMG/RuleDB/ContentTypeFilter.pm
> index e44bf3c..6818de1 100644
> --- a/src/PMG/RuleDB/ContentTypeFilter.pm
> +++ b/src/PMG/RuleDB/ContentTypeFilter.pm
> @@ -35,7 +35,7 @@ sub new {
>   	$fvalue = $nt;
>       }
>   
> -    my $self = $class->SUPER::new('content-type', $fvalue, $ogroup);
> +    my $self = $class->SUPER::new('content-type', $fvalue, $ogroup, undef);
>       $self->{only_content} = $only_content;
>   
>       return $self;
> diff --git a/src/PMG/RuleDB/MatchField.pm b/src/PMG/RuleDB/MatchField.pm
> index ee1851a..f6787e8 100644
> --- a/src/PMG/RuleDB/MatchField.pm
> +++ b/src/PMG/RuleDB/MatchField.pm
> @@ -27,7 +27,7 @@ sub otype_text {
>   }
>   
>   sub new {
> -    my ($type, $field, $field_value, $ogroup) = @_;
> +    my ($type, $field, $field_value, $ogroup, $top_part_only) = @_;
>   
>       my $class = ref($type) || $type;
>   
> @@ -35,6 +35,7 @@ sub new {
>   
>       $self->{field} = $field;
>       $self->{field_value} = $field_value;
> +    $self->{top_part_only} = $top_part_only;
>   
>       return $self;
>   }
> @@ -54,12 +55,28 @@ sub load_attr {
>       my $decoded_field_value = PMG::Utils::try_decode_utf8($field_value);
>       # use known constructor, bless afterwards (because sub class can have constructor
>       # with other parameter signature).
> -    my $obj =  PMG::RuleDB::MatchField->new($field, $decoded_field_value, $ogroup);
> +    my $obj =  PMG::RuleDB::MatchField->new($field, $decoded_field_value, $ogroup, undef);
>       bless $obj, $class;
>   
> +    my $sth = $ruledb->{dbh}->prepare(
> +	"SELECT * FROM Attribut WHERE Object_ID = ?");
> +
> +    $sth->execute($id);
> +
> +    $obj->{top_part_only} = 0;
> +
> +    while (my $ref = $sth->fetchrow_hashref()) {
> +	if ($ref->{name} eq 'top_part_only') {
> +	    $obj->{top_part_only} = $ref->{value};
> +	}
> +    }
> +
> +    $sth->finish();
> +
>       $obj->{id} = $id;
>   
> -    $obj->{digest} = Digest::SHA::sha1_hex($id, $field, $field_value, $ogroup);
> +    $obj->{digest} = Digest::SHA::sha1_hex(
> +	$id, $field, $field_value, $ogroup, $obj->{top_part_only});
>   
>       return $obj;
>   }
> @@ -79,6 +96,9 @@ sub save {
>   
>       if (defined ($self->{id})) {
>   	# update
> +	$ruledb->{dbh}->do(
> +	    "DELETE FROM Attribut WHERE Object_ID = ?",
> +	    undef, $self->{id});
>   
>   	$ruledb->{dbh}->do(
>   	    "UPDATE Object SET Value = ? WHERE ID = ?",
> @@ -96,6 +116,12 @@ sub save {
>   	$self->{id} = PMG::Utils::lastid($ruledb->{dbh}, 'object_id_seq');
>       }
>   
> +    if (defined($self->{top_part_only})) {
> +	$ruledb->{dbh}->do(
> +	    "INSERT INTO Attribut (Value, Name, Object_ID) VALUES (?, 'top_part_only', ?)",
> +	    undef, $self->{top_part_only}, $self->{id});
> +    }
> +
>       return $self->{id};
>   }
>   
> @@ -124,6 +150,8 @@ sub parse_entity {
>   	}
>       }
>   
> +    return $res if $self->{top_part_only};
> +
>       foreach my $part ($entity->parts)  {
>   	if (my $match = $self->parse_entity($part)) {
>   	    push @$res, @$match;
> @@ -160,6 +188,12 @@ sub properties {
>   	    type => 'string',
>   	    maxLength => 1024,
>   	},
> +	'top-part-only' => {
> +	    description => "only match the headers in the first MIME-Part",
> +	    type => 'boolean',
> +	    optional => 1,
> +	    default => 0,
> +	},
>       };
>   }
>   
> @@ -169,6 +203,7 @@ sub get {
>       return {
>   	field => $self->{field},
>   	value => $self->{field_value},
> +	'top-part-only' => $self->{top_part_only},
>       };
>   }
>   
> @@ -177,6 +212,12 @@ sub update {
>   
>       $self->{field_value} = $param->{value};
>       $self->{field} = $param->{field};
> +
> +    if (defined($param->{'top-part-only'}) && $param->{'top-part-only'} == 1) {
> +	$self->{top_part_only} = 1;
> +    } else {
> +	delete $self->{top_part_only};
> +    }
>   }
>   
>   1;