@matheusbsbs / matheus-bagliano / commits / 0866786b80

gitweb: Strip non-printable characters from syntax highlighter output

The current code, as is, passes control characters, such as form-feed (^L) to highlight which then passes it through to the browser. User agents (web browsers) that support 'application/xhtml+xml' usually require that web pages declared as XHTML and with this mimetype are well-formed XML. Unescaped control characters cannot appear within a contents of a valid XML document. This will cause the browser to display one of the following warnings: * Safari v5.1 (6534.50) & Google Chrome v13.0.782.112: This page contains the following errors: error on line 657 at column 38: PCDATA invalid Char value 12 Below is a rendering of the page up to the first error. * Mozilla Firefox 3.6.19 & Mozilla Firefox 5.0: XML Parsing Error: not well-formed Location: http://path/to/git/repo/blah/blah Both errors were generated by gitweb.perl v1.7.3.4 w/ highlight 2.7 using arch/ia64/kernel/unwind.c from the Linux kernel. When syntax highlighter is not used, control characters are replaced by esc_html(), but with syntax highlighter they were passed through to browser (to_utf8() doesn't remove control characters). Introduce sanitize() subroutine which strips forbidden characters, but does not perform HTML escaping, and use it in git_blob() to sanitize syntax highlighter output for XHTML. Note that excluding "\t" (U+0009), "\n" (U+000A) and "\r" (U+000D) is not strictly necessary, atleast for currently the only callsite: "\t" tabs are replaced by spaces by untabify(), "\n" is stripped from each line before processing it, and replacing "\r" could be considered improvement. Originally-by: Christopher M. Fuhrman <cfuhrman@panix.com> Signed-off-by: Jakub Narebski <jnareb@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jakub Narebski committed Sep 16, 2011 at 14:41 UTC 0866786b80aa921576ab4e7474c91207111f970f

1 file changed +13 -1

gitweb/gitweb.perl

+13 -1

@@ -1517,6 +1517,17 @@ sub esc_path {

1517 return $str;

1518 }

1519

1520 +# Sanitize for use in XHTML + application/xml+xhtm (valid XML 1.0)

1521 +sub sanitize {

1522 + my $str = shift;

1523 +

1524 + return undef unless defined $str;

1525 +

1526 + $str = to_utf8($str);

1527 + $str =~ s|([[:cntrl:]])|($1 =~ /[\t\n\r]/ ? $1 : quot_cec($1))|eg;

1528 + return $str;

1529 +}

1530 +

1531 # Make control characters "printable", using character escape codes (CEC)

1532 sub quot_cec {

1533 my $cntrl = shift;

@@ -6484,7 +6495,8 @@ sub git_blob {

6495 $nr++;

6496 $line = untabify($line);

6497 printf qq!<div class="pre"><a id="l%i" href="%s#l%i" class="linenr">%4i</a> %s</div>\n!,

6487 - $nr, esc_attr(href(-replay => 1)), $nr, $nr, $syntax ? to_utf8($line) : esc_html($line, -nbsp=>1);

6498 + $nr, esc_attr(href(-replay => 1)), $nr, $nr,

6499 + $syntax ? sanitize($line) : esc_html($line, -nbsp=>1);

6500 }

6501 }

6502 close $fd