properly handle invalid regular expressions supplied when testing filters, add some additional regexp checks (closes #427)

4 files changed, 135 insertions, 94 deletions

diff --git a/classes/pref_filters.php b/classes/pref_filters.php
index c66e9e810..9b8c295ff 100644
--- a/classes/pref_filters.php
+++ b/classes/pref_filters.php
@@ -33,55 +33,65 @@ class Pref_Filters extends Protected_Handler {
 		else
 			$feed = -4;
 
-		$feed_title = getFeedTitle($this->link, $feed);
-
-		$qfh_ret = queryFeedHeadlines($this->link, $cat_filter ? $cat_id : $feed,
-			30, "", $cat_filter, false, false,
-			false, "date_entered DESC", 0, $_SESSION["uid"], $filter);
-
-		$result = $qfh_ret[0];
-
-		$articles = array();
-		$found = 0;
+		$regexp_valid = preg_match('/' . $filter['reg_exp'] . '/',
+			$filter['reg_exp']) !== FALSE;
 
 		print __("Articles matching this filter:");
 
 		print "<div class=\"inactiveFeedHolder\">";
 		print "<table width=\"100%\" cellspacing=\"0\" id=\"prefErrorFeedList\">";
 
-		while ($line = db_fetch_assoc($result)) {
+		if ($regexp_valid) {
 
-			$entry_timestamp = strtotime($line["updated"]);
-			$entry_tags = get_article_tags($this->link, $line["id"], $_SESSION["uid"]);
+			$feed_title = getFeedTitle($this->link, $feed);
 
-			$content_preview = truncate_string(
-				strip_tags($line["content_preview"]), 100, '...');
+			$qfh_ret = queryFeedHeadlines($this->link, $cat_filter ? $cat_id : $feed,
+				30, "", $cat_filter, false, false,
+				false, "date_entered DESC", 0, $_SESSION["uid"], $filter);
 
-			if ($line["feed_title"])
-				$feed_title = $line["feed_title"];
+			$result = $qfh_ret[0];
 
-			print "<tr>";
+			$articles = array();
+			$found = 0;
 
-			print "<td width='5%' align='center'><input
-				dojoType=\"dijit.form.CheckBox\" checked=\"1\"
-				disabled=\"1\" type=\"checkbox\"></td>";
-			print "<td>";
+			while ($line = db_fetch_assoc($result)) {
 
-			print $line["title"];
-			print "&nbsp;(";
-			print "<b>" . $feed_title . "</b>";
-			print "):&nbsp;";
-			print "<span class=\"insensitive\">" . $content_preview . "</span>";
-			print " " . mb_substr($line["date_entered"], 0, 16);
+				$entry_timestamp = strtotime($line["updated"]);
+				$entry_tags = get_article_tags($this->link, $line["id"], $_SESSION["uid"]);
 
-			print "</td></tr>";
+				$content_preview = truncate_string(
+					strip_tags($line["content_preview"]), 100, '...');
 
-			$found++;
-		}
+				if ($line["feed_title"])
+					$feed_title = $line["feed_title"];
+
+				print "<tr>";
+
+				print "<td width='5%' align='center'><input
+					dojoType=\"dijit.form.CheckBox\" checked=\"1\"
+					disabled=\"1\" type=\"checkbox\"></td>";
+				print "<td>";
+
+				print $line["title"];
+				print "&nbsp;(";
+				print "<b>" . $feed_title . "</b>";
+				print "):&nbsp;";
+				print "<span class=\"insensitive\">" . $content_preview . "</span>";
+				print " " . mb_substr($line["date_entered"], 0, 16);
+
+				print "</td></tr>";
+
+				$found++;
+			}
+
+			if ($found == 0) {
+				print "<tr><td align='center'>" .
+					__("No articles matching this filter has been found.") . "</td></tr>";
+			}
+		} else {
+			print "<tr><td align='center' class='error'>" .
+				__("Invalid regular expression.") . "</td></tr>";
 
-		if ($found == 0) {
-			print "<tr><td align='center'>" .
-				__("No articles matching this filter has been found.") . "</td></tr>";
 		}
 
 		print "</table>";
diff --git a/include/functions.php b/include/functions.php
index 25c188ee6..dc5cbc816 100644
--- a/include/functions.php
+++ b/include/functions.php
@@ -4973,63 +4973,70 @@
 	function filter_to_sql($filter) {
 		$query = "";
 
-		if (DB_TYPE == "pgsql")
-			$reg_qpart = "~";
-		else
-			$reg_qpart = "REGEXP";
+		$regexp_valid = preg_match('/' . $filter['reg_exp'] . '/',
+			$filter['reg_exp']) !== FALSE;
 
-		switch ($filter["type"]) {
-			case "title":
-				$query = "LOWER(ttrss_entries.title) $reg_qpart LOWER('".
-					$filter['reg_exp'] . "')";
-				break;
-			case "content":
-				$query = "LOWER(ttrss_entries.content) $reg_qpart LOWER('".
-					$filter['reg_exp'] . "')";
-				break;
-			case "both":
-				$query = "LOWER(ttrss_entries.title) $reg_qpart LOWER('".
-					$filter['reg_exp'] . "') OR LOWER(" .
-					"ttrss_entries.content) $reg_qpart LOWER('" . $filter['reg_exp'] . "')";
-				break;
-			case "tag":
-				$query = "LOWER(ttrss_user_entries.tag_cache) $reg_qpart LOWER('".
-					$filter['reg_exp'] . "')";
-				break;
-			case "link":
-				$query = "LOWER(ttrss_entries.link) $reg_qpart LOWER('".
-					$filter['reg_exp'] . "')";
-				break;
-			case "date":
+		if ($regexp_valid) {
 
-				if ($filter["filter_param"] == "before")
-					$cmp_qpart = "<";
-				else
-					$cmp_qpart = ">=";
+			if (DB_TYPE == "pgsql")
+				$reg_qpart = "~";
+			else
+				$reg_qpart = "REGEXP";
 
-				$timestamp = date("Y-m-d H:N:s", strtotime($filter["reg_exp"]));
-				$query = "ttrss_entries.date_entered $cmp_qpart '$timestamp'";
-				break;
-			case "author":
-				$query = "LOWER(ttrss_entries.author) $reg_qpart LOWER('".
-					$filter['reg_exp'] . "')";
-				break;
-		}
+			switch ($filter["type"]) {
+				case "title":
+					$query = "LOWER(ttrss_entries.title) $reg_qpart LOWER('".
+						$filter['reg_exp'] . "')";
+					break;
+				case "content":
+					$query = "LOWER(ttrss_entries.content) $reg_qpart LOWER('".
+						$filter['reg_exp'] . "')";
+					break;
+				case "both":
+					$query = "LOWER(ttrss_entries.title) $reg_qpart LOWER('".
+						$filter['reg_exp'] . "') OR LOWER(" .
+						"ttrss_entries.content) $reg_qpart LOWER('" . $filter['reg_exp'] . "')";
+					break;
+				case "tag":
+					$query = "LOWER(ttrss_user_entries.tag_cache) $reg_qpart LOWER('".
+						$filter['reg_exp'] . "')";
+					break;
+				case "link":
+					$query = "LOWER(ttrss_entries.link) $reg_qpart LOWER('".
+						$filter['reg_exp'] . "')";
+					break;
+				case "date":
 
-		if ($filter["inverse"])
-			$query = "NOT ($query)";
+					if ($filter["filter_param"] == "before")
+						$cmp_qpart = "<";
+					else
+						$cmp_qpart = ">=";
 
-		if ($query) {
-			if (DB_TYPE == "pgsql") {
-				$query = " ($query) AND ttrss_entries.date_entered > NOW() - INTERVAL '14 days'";
-			} else {
-				$query = " ($query) AND ttrss_entries.date_entered > DATE_SUB(NOW(), INTERVAL 14 DAY)";
+					$timestamp = date("Y-m-d H:N:s", strtotime($filter["reg_exp"]));
+					$query = "ttrss_entries.date_entered $cmp_qpart '$timestamp'";
+					break;
+				case "author":
+					$query = "LOWER(ttrss_entries.author) $reg_qpart LOWER('".
+						$filter['reg_exp'] . "')";
+					break;
 			}
-			$query .= " AND ";
-		}
 
+			if ($filter["inverse"])
+				$query = "NOT ($query)";
 
-		return $query;
+			if ($query) {
+				if (DB_TYPE == "pgsql") {
+					$query = " ($query) AND ttrss_entries.date_entered > NOW() - INTERVAL '14 days'";
+				} else {
+					$query = " ($query) AND ttrss_entries.date_entered > DATE_SUB(NOW(), INTERVAL 14 DAY)";
+				}
+				$query .= " AND ";
+			}
+
+			return $query;
+		} else {
+			return false;
+		}
 	}
 
 	// Status codes:
diff --git a/js/functions.js b/js/functions.js
index bd0d5fb73..4a4602f9e 100644
--- a/js/functions.js
+++ b/js/functions.js
@@ -982,19 +982,39 @@ function quickAddFilter() {
 			test: function() {
 				if (this.validate()) {
 
-					if (dijit.byId("filterTestDlg"))
-						dijit.byId("filterTestDlg").destroyRecursive();
+					var query = "?op=rpc&method=verifyRegexp&reg_exp=" +
+						param_escape(dialog.attr('value').reg_exp);
+
+					notify_progress("Verifying regular expression...");
+
+					new Ajax.Request("backend.php",	{
+						parameters: query,
+						onComplete: function(transport) {
+							var reply = JSON.parse(transport.responseText);
+
+							if (reply) {
+								notify('');
+
+								if (!reply['status']) {
+									alert("Invalid regular expression.");
+									return;
+								} else {
 
-					tdialog = new dijit.Dialog({
-						id: "filterTestDlg",
-						title: __("Filter Test Results"),
-						style: "width: 600px",
-						href: "backend.php?savemode=test&" +
-							dojo.objectToQuery(dialog.attr('value')),
-						});
+									if (dijit.byId("filterTestDlg"))
+										dijit.byId("filterTestDlg").destroyRecursive();
 
-					tdialog.show();
+									tdialog = new dijit.Dialog({
+										id: "filterTestDlg",
+										title: __("Filter Test Results"),
+										style: "width: 600px",
+										href: "backend.php?savemode=test&" +
+										dojo.objectToQuery(dialog.attr('value')),
+									});
 
+									tdialog.show();
+								}
+							}
+					}});
 				}
 			},
 			execute: function() {
@@ -1014,7 +1034,7 @@ function quickAddFilter() {
 								notify('');
 
 								if (!reply['status']) {
-									alert("Match regular expression seems to be invalid.");
+									alert("Invalid regular expression.");
 									return;
 								} else {
 									notify_progress("Saving data...", true);
diff --git a/tt-rss.css b/tt-rss.css
index 94aa75874..7a0ef8bbb 100644
--- a/tt-rss.css
+++ b/tt-rss.css
@@ -1407,3 +1407,7 @@ a.bookmarklet {
 	padding : 1em;
 	color : gray;
 }
+
+td.error { 
+	color : red;
+}