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[PATCH 3/5] gitweb: Split validate_input into validate_pathname and validate_refname

From
Jakub Narebski <jnareb@gmail.com>
Date
Sep 25, 2006, 23:57 UTC
Message-ID
<200609260157.03035.jnareb@gmail.com>
In-Reply-To
<200609260153.08503.jnareb@gmail.com>

Split validate_input subroutine into validate_pathname which is used for $project, $file_name and $file_parent parameters, and validate_refname which is used for $hash, $hash_base, $hash_parent and $hash_parent_base parameters. Reintroduce validation of $file_name and $file_parent parameters, removed in a2f3db2f5de2a3667b0e038aa65e3

validate_pathname in addition to what validate_input did checks also for doubled slashes and NUL character. It does not check if input is textual hash, and does not check if all characters are from the following set: [a-zA-Z0-9_\x80-\xff\ \t\.\/\-\+\#\~\%].

validate_refname first check if the input is textual hash, then checks if it is valid pathname, then checks for invalid characters (according to git-check-ref-format manpage). It does not check if all charactes are from the [a-zA-Z0-9_\x80-\xff\ \t\.\/\-\+\#\~\%] set.

We do not reintroduce validating pathnames we got from git.
Signed-off-by: Jakub Narebski <jnareb@gmail.com>
---
At last.
 gitweb/gitweb.perl |   66 +++++++++++++++++++++++++++++++++++++++-------------
 1 files changed, 50 insertions(+), 16 deletions(-)
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 6458d7b..7fce9a6 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -200,9 +200,10 @@ if (defined $action) {
 	}
 }
 
+# parameters which are pathnames
 our $project = $cgi->param('p');
 if (defined $project) {
-	if (!validate_input($project) ||
+	if (!validate_pathname($project) ||
 	    !(-d "$projectroot/$project") ||
 	    !(-e "$projectroot/$project/HEAD") ||
 	    ($export_ok && !(-e "$projectroot/$project/$export_ok")) ||
@@ -212,38 +213,50 @@ if (defined $project) {
 	}
 }
 
-# We have to handle those containing any characters:
 our $file_name = $cgi->param('f');
+if (defined $file_name) {
+	if (!validate_pathname($file_name)) {
+		die_error(undef, "Invalid file parameter");
+	}
+}
+
 our $file_parent = $cgi->param('fp');
+if (defined $file_parent) {
+	if (!validate_pathname($file_parent)) {
+		die_error(undef, "Invalid file parent parameter");
+	}
+}
 
+# parameters which are refnames
 our $hash = $cgi->param('h');
 if (defined $hash) {
-	if (!validate_input($hash)) {
+	if (!validate_refname($hash)) {
 		die_error(undef, "Invalid hash parameter");
 	}
 }
 
 our $hash_parent = $cgi->param('hp');
 if (defined $hash_parent) {
-	if (!validate_input($hash_parent)) {
+	if (!validate_refname($hash_parent)) {
 		die_error(undef, "Invalid hash parent parameter");
 	}
 }
 
 our $hash_base = $cgi->param('hb');
 if (defined $hash_base) {
-	if (!validate_input($hash_base)) {
+	if (!validate_refname($hash_base)) {
 		die_error(undef, "Invalid hash base parameter");
 	}
 }
 
 our $hash_parent_base = $cgi->param('hpb');
 if (defined $hash_parent_base) {
-	if (!validate_input($hash_parent_base)) {
+	if (!validate_refname($hash_parent_base)) {
 		die_error(undef, "Invalid hash parent base parameter");
 	}
 }
 
+# other parameters
 our $page = $cgi->param('pg');
 if (defined $page) {
 	if ($page =~ m/[^0-9]/) {
@@ -273,7 +286,7 @@ sub evaluate_path_info {
 		$project =~ s,/*[^/]*$,,;
 	}
 	# validate project
-	$project = validate_input($project);
+	$project = validate_pathname($project);
 	if (!$project ||
 	    ($export_ok && !-e "$projectroot/$project/$export_ok") ||
 	    ($strict_export && !project_in_list($project))) {
@@ -294,12 +307,12 @@ sub evaluate_path_info {
 		} else {
 			$action  ||= "blob_plain";
 		}
-		$hash_base ||= validate_input($refname);
-		$file_name ||= $pathname;
+		$hash_base ||= validate_refname($refname);
+		$file_name ||= validate_pathname($pathname);
 	} elsif (defined $refname) {
 		# we got "project.git/branch"
 		$action ||= "shortlog";
-		$hash   ||= validate_input($refname);
+		$hash   ||= validate_refname($refname);
 	}
 }
 evaluate_path_info();
@@ -387,16 +400,37 @@ sub href(%) {
 ## ======================================================================
 ## validation, quoting/unquoting and escaping
 
-sub validate_input {
-	my $input = shift;
+sub validate_pathname {
+	my $input = shift || return undef;
 
-	if ($input =~ m/^[0-9a-fA-F]{40}$/) {
-		return $input;
+	# no '.' or '..' as elements of path, i.e. no '.' nor '..'
+	# at the beginning, at the end, and between slashes.
+	if ($input =~ m!(^|/)(|\.|\.\.)(/|$)!) {
+		return undef;
 	}
-	if ($input =~ m/(^|\/)(|\.|\.\.)($|\/)/) {
+	# no doubled slashes
+	if ($input =~ m!//!) {
 		return undef;
 	}
-	if ($input =~ m/[^a-zA-Z0-9_\x80-\xff\ \t\.\/\-\+\#\~\%]/) {
+	# no null characters
+	if ($input =~ m!\0!) {
+		return undef;
+	}
+	return $input;
+}
+
+sub validate_refname {
+	my $input = shift || return undef;
+
+	# textual hashes are O.K.
+	if ($input =~ m/^[0-9a-fA-F]{40}$/) {
+		return $input;
+	}
+	# it must be correct pathname
+	$input = validate_pathname($input)
+		or return undef;
+	# restrictions on ref name according to git-check-ref-format
+	if ($input =~ m!(/\.|\.\.|[\000-\040\177 ~^:?*\[]|/$)!) {
 		return undef;
 	}
 	return $input;
-- 
1.4.2.1
Previous: Jakub NarebskiNext: Junio C Hamano
Message 4 of 10 in “gitweb: A few code cleanup patches”
  1. 0/5 gitweb: A few code cleanup patchesJakub Narebski, Sep 25, 2006
  2. 1/5 gitweb: Strip trailing slashes from $path in git_get_hash_by_pathJakub Narebski, Sep 25, 2006
  3. 2/5 gitweb: Use "return" instead of "return undef" for some subsJakub Narebski, Sep 25, 2006
  4. 3/5 gitweb: Split validate_input into validate_pathname and validate_refnameJakub Narebski, Sep 25, 2006
  5. Junio C HamanoSep 26, 2006
  6. Jakub NarebskiSep 26, 2006
  7. 4/5 gitweb: Add git_url subroutine, and use it to quote full URLsJakub Narebski, Sep 25, 2006
  8. 5/5 gitweb: Quote filename in HTTP Content-Disposition: headerJakub Narebski, Sep 25, 2006
  9. Junio C HamanoSep 26, 2006
  10. Jakub NarebskiSep 26, 2006

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