[pmg-devel] [PATCH pmg-api v3] fix #4811: rule db: test regex validity on save

[Dominik Csapak <d.csapak@proxmox.com>]

and warn only when it's an invalid regex on execution, because users may
have previously had such rules. Otherwise, pmg-smtp-filter will restart
every time it encounters such a rule.

When testing, 'die' if the regex execution 'warns', so that users cannot
enter a semi-invalid or very wrong regex like '^*foo$'.

do so for every rule type that uses a regex to match

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 src/PMG/RuleDB/ArchiveFilter.pm        |  6 ++++++
 src/PMG/RuleDB/ContentTypeFilter.pm    |  7 +++++++
 src/PMG/RuleDB/MatchArchiveFilename.pm |  7 +++++++
 src/PMG/RuleDB/MatchField.pm           |  4 +---
 src/PMG/RuleDB/MatchFilename.pm        | 12 +++++++++---
 src/PMG/RuleDB/WhoRegex.pm             | 10 +++++++++-
 src/PMG/Utils.pm                       | 10 ++++++++++
 7 files changed, 49 insertions(+), 7 deletions(-)

diff --git a/src/PMG/RuleDB/ArchiveFilter.pm b/src/PMG/RuleDB/ArchiveFilter.pm
index 6d91556..3d9890c 100644
--- a/src/PMG/RuleDB/ArchiveFilter.pm
+++ b/src/PMG/RuleDB/ArchiveFilter.pm
@@ -48,6 +48,12 @@ sub parse_entity {
 
     my $res;
 
+    # test regex for validity
+    eval { "" =~ m|$self->{field_value}|; };
+    if (my $err = $@) {
+	warn "invalid regex: $err\n";
+	return $res;
+    }
     # match subtypes? We currently do exact matches only.
 
     if (my $id = $entity->head->mime_attr ('x-proxmox-tmp-aid')) {
diff --git a/src/PMG/RuleDB/ContentTypeFilter.pm b/src/PMG/RuleDB/ContentTypeFilter.pm
index 76fc1ce..0199311 100644
--- a/src/PMG/RuleDB/ContentTypeFilter.pm
+++ b/src/PMG/RuleDB/ContentTypeFilter.pm
@@ -60,6 +60,13 @@ sub parse_entity {
 
     my $res;
 
+    # test regex for validity
+    eval { "" =~ m|$self->{field_value}|; };
+    if (my $err = $@) {
+	warn "invalid regex: $err\n";
+	return $res;
+    }
+
     # match subtypes? We currently do exact matches only.
 
     if (my $id = $entity->head->mime_attr ('x-proxmox-tmp-aid')) {
diff --git a/src/PMG/RuleDB/MatchArchiveFilename.pm b/src/PMG/RuleDB/MatchArchiveFilename.pm
index 2ef3543..5b1cb6d 100644
--- a/src/PMG/RuleDB/MatchArchiveFilename.pm
+++ b/src/PMG/RuleDB/MatchArchiveFilename.pm
@@ -25,6 +25,13 @@ sub parse_entity {
 
     my $res;
 
+    # test regex for validity
+    eval { "" =~ m|^$self->{fname}$|i; };
+    if (my $err = $@) {
+	warn "invalid regex: $err\n";
+	return $res;
+    }
+
     if (my $id = $entity->head->mime_attr('x-proxmox-tmp-aid')) {
 	chomp $id;
 
diff --git a/src/PMG/RuleDB/MatchField.pm b/src/PMG/RuleDB/MatchField.pm
index 177a283..ee1851a 100644
--- a/src/PMG/RuleDB/MatchField.pm
+++ b/src/PMG/RuleDB/MatchField.pm
@@ -71,9 +71,7 @@ sub save {
 
     my $regex = $self->{field_value};
 
-    # test regex for validity
-    eval { "" =~ /$regex/i; };
-    die "invalid regex: $@\n" if $@;
+    PMG::Utils::test_regex($regex);
 
     my $new_value = "$self->{field}:$regex";
     $new_value =~ s/\\/\\\\/g;
diff --git a/src/PMG/RuleDB/MatchFilename.pm b/src/PMG/RuleDB/MatchFilename.pm
index c9cdbe0..90f8654 100644
--- a/src/PMG/RuleDB/MatchFilename.pm
+++ b/src/PMG/RuleDB/MatchFilename.pm
@@ -58,6 +58,9 @@ sub save {
     defined($self->{ogroup}) || die "undefined ogroup: ERROR";
 
     my $new_value = $self->{fname};
+
+    PMG::Utils::test_regex("^${new_value}\$");
+
     $new_value =~ s/\\/\\\\/g;
     $new_value = encode('UTF-8', $new_value);
 
@@ -91,9 +94,12 @@ sub parse_entity {
 	chomp $id;
 
 	if (my $value = PMG::Utils::extract_filename($entity->head)) {
-	    if ($value =~ m|^$self->{fname}$|i) {
-		push @$res, $id;
-	    }
+	    eval {
+		if ($value =~ m|^$self->{fname}$|i) {
+		    push @$res, $id;
+		}
+	    };
+	    warn "invalid regex: $@\n" if $@;
 	}
     }
 
diff --git a/src/PMG/RuleDB/WhoRegex.pm b/src/PMG/RuleDB/WhoRegex.pm
index 5c13604..03405bc 100644
--- a/src/PMG/RuleDB/WhoRegex.pm
+++ b/src/PMG/RuleDB/WhoRegex.pm
@@ -60,6 +60,9 @@ sub save {
     defined($self->{address}) || die "undefined address: ERROR";
 
     my $adr = $self->{address};
+
+    PMG::Utils::test_regex("^${adr}\$");
+
     $adr =~ s/\\/\\\\/g;
     $adr = encode('UTF-8', $adr);
 
@@ -100,7 +103,12 @@ sub who_match {
 
     my $t = $self->address;
 
-    return $addr =~ m/^$t$/i;
+    my $res;
+    eval {
+	$res = $addr =~ m/^$t$/i;
+    };
+    warn "invalid regex: $@\n" if $@;
+    return $res;
 }
 
 sub address { 
diff --git a/src/PMG/Utils.pm b/src/PMG/Utils.pm
index d9c9d2d..da1d81b 100644
--- a/src/PMG/Utils.pm
+++ b/src/PMG/Utils.pm
@@ -1580,4 +1580,14 @@ sub try_decode_utf8 {
     return eval { decode('UTF-8', $data, 1) } // $data;
 }
 
+sub test_regex {
+    my ($regex) = @_;
+
+    local $SIG{__WARN__} = sub { die @_ };
+    eval { "" =~ m/$regex/i; };
+    die "invalid regex: $@\n" if $@;
+
+    return undef;
+}
+
 1;
-- 
2.39.2