merged branches/177 (trac #177).

(with the usual prop change to rrsig_46.cc)


git-svn-id: svn://bind10.isc.org/svn/bind10/trunk@1806 e5f2f494-b856-4b98-b285-d166d9295462

src/lib/dns/name.cc

@@ -667,7 +667,7 @@ Name::reverse() const {
 
 Name
 Name::split(unsigned int first, unsigned int n) const {
-    if (n == 0 || first + n > labelcount_) {
+    if (n == 0 || n > labelcount_ || first > labelcount_ - n) {
         isc_throw(OutOfRange, "Name::split: invalid split range");
     }
 

src/lib/dns/tests/name_unittest.cc

@@ -18,6 +18,7 @@
 #include <string>
 #include <sstream>
 #include <iomanip>
+#include <limits>
 #include <stdexcept>
 
 #include <dns/buffer.h>
@@ -492,6 +493,11 @@ TEST_F(NameTest, split) {
     // invalid range: an exception should be thrown.
     EXPECT_THROW(example_name.split(1, 0), OutOfRange);
     EXPECT_THROW(example_name.split(2, 3), OutOfRange);
+
+    // invalid range: the following parameters would cause overflow,
+    // bypassing naive validation.
+    EXPECT_THROW(example_name.split(1, numeric_limits<unsigned int>::max()),
+                 OutOfRange);
 }
 
 TEST_F(NameTest, downcase) {