From: Dirk-Jan C. Binnema <dirk-jan.binnema@nokia.com>
Date: Sun, 8 Jul 2007 10:32:26 +0000 (+0000)
Subject: * include artificial breakpoints in very long (>256 chars) lines; this will make... 
X-Git-Tag: git_migration_finished~2911
X-Git-Url: http://git.maemo.org/git/?p=modest;a=commitdiff_plain;h=95a844036e2eb46e1c59838899e9334d236181a3

* include artificial breakpoints in very long (>256 chars) lines; this will make sure the regexp parsing is not DoS'ing modest in some pathological cases.

the problem was that we do a text->html conversion for showing messages, and
  run some regexps to hyperlinkify things that look like email addresses etc.,
  when lines are really long, this takes a *lot* of time.

  Fixes: NB#62530

pmo-trunk-r2627
---

diff --git a/src/modest-text-utils.c b/src/modest-text-utils.c
index 52d9ecf..3c32ada 100644
--- a/src/modest-text-utils.c
+++ b/src/modest-text-utils.c
@@ -300,6 +300,7 @@ modest_text_utils_convert_buffer_to_html (GString *html, const gchar *data)
 	guint		 i;
 	gboolean	space_seen = FALSE;
 	gsize           len;
+	guint           break_dist = 0; /* distance since last break point */
 
 	len = strlen (data);
 
@@ -312,6 +313,15 @@ modest_text_utils_convert_buffer_to_html (GString *html, const gchar *data)
 			space_seen = FALSE;
 		}
 		
+		/* we artificially insert a breakpoint (newline)
+		 * after 256, to make sure our lines are not so long
+		 * they will DOS the regexping later
+		 */
+		if (++break_dist == 256) {
+			g_string_append_c (html, '\n');
+			break_dist = 0;
+		}
+		
 		switch (kar) {
 		case 0:  break; /* ignore embedded \0s */	
 		case '<'  : g_string_append (html, "&lt;");   break;
@@ -319,9 +329,10 @@ modest_text_utils_convert_buffer_to_html (GString *html, const gchar *data)
 		case '&'  : g_string_append (html, "&amp;");  break;
 		case '"'  : g_string_append (html, "&quot;");  break;
 		case '\'' : g_string_append (html, "&apos;"); break;
-		case '\n' : g_string_append (html, "<br>\n");  break;
-		case '\t' : g_string_append (html, "&nbsp;&nbsp;&nbsp; "); break; /* note the space at the end*/
+		case '\n' : g_string_append (html, "<br>\n");              break_dist= 0; break;
+		case '\t' : g_string_append (html, "&nbsp;&nbsp;&nbsp; "); break_dist=0; break; /* note the space at the end*/
 		case ' ':
+			break_dist = 0;
 			if (space_seen) { /* second space in a row */
 				g_string_append (html, "&nbsp; ");
 				space_seen = FALSE;