- improve dname_has_label(), add unit test

diff --git a/testcode/unitdname.c b/testcode/unitdname.c
index 238c3edf7ade12a40465a5933d816b11b84ca450..b0c3fb057034c2f4ed13bd9d3ef390e64bd9bb2a 100644 (file)
--- a/testcode/unitdname.c
+++ b/testcode/unitdname.c
@@ -794,6 +794,33 @@ dname_test_valid(void)
                , 4096) == 0);
 }
 
+/** Test dname_has_label */
+static void
+dname_test_has_label(void)
+{
+       unit_show_func("util/data/dname.c", "dname_has_label");
+       /* label past root label */
+       unit_assert(dname_has_label((uint8_t*)"\01a\0\01c", 5, (uint8_t*)"\01c") == 0);
+       /* label not found */
+       unit_assert(dname_has_label((uint8_t*)"\02ab\01c\0", 6, (uint8_t*)"\01e") == 0);
+       /* buffer too short */
+       unit_assert(dname_has_label((uint8_t*)"\02ab\01c\0", 5, (uint8_t*)"\0") == 0);
+       unit_assert(dname_has_label((uint8_t*)"\1a\0", 2, (uint8_t*)"\0") == 0);
+       unit_assert(dname_has_label((uint8_t*)"\02ab\01c", 4, (uint8_t*)"\01c") == 0);
+       unit_assert(dname_has_label((uint8_t*)"\02ab\03qwe\06oqieur\03def\01c\0", 19, (uint8_t*)"\01c") == 0);
+
+       /* positive cases  */
+       unit_assert(dname_has_label((uint8_t*)"\0", 1, (uint8_t*)"\0") == 1);
+       unit_assert(dname_has_label((uint8_t*)"\1a\0", 3, (uint8_t*)"\0") == 1);
+       unit_assert(dname_has_label((uint8_t*)"\01a\0\01c", 5, (uint8_t*)"\0") == 1);
+       unit_assert(dname_has_label((uint8_t*)"\02ab\01c", 5, (uint8_t*)"\01c") == 1);
+       unit_assert(dname_has_label((uint8_t*)"\02ab\01c\0", 10, (uint8_t*)"\0") == 1);
+       unit_assert(dname_has_label((uint8_t*)"\02ab\01c\0", 7, (uint8_t*)"\0") == 1);
+       unit_assert(dname_has_label((uint8_t*)"\02ab\03qwe\06oqieur\03def\01c\0", 22, (uint8_t*)"\03def") == 1);
+       unit_assert(dname_has_label((uint8_t*)"\02ab\03qwe\06oqieur\03def\01c\0", 22, (uint8_t*)"\02ab") == 1);
+       unit_assert(dname_has_label((uint8_t*)"\02ab\03qwe\06oqieur\03def\01c\0", 22, (uint8_t*)"\01c") == 1);
+}
+
 /** test pkt_dname_tolower */
 static void
 dname_test_pdtl(sldns_buffer* loopbuf, sldns_buffer* boundbuf)
@@ -855,6 +882,7 @@ void dname_test(void)
        dname_test_canoncmp();
        dname_test_topdomain();
        dname_test_valid();
+       dname_test_has_label();
        sldns_buffer_free(buff);
        sldns_buffer_free(loopbuf);
        sldns_buffer_free(boundbuf);

diff --git a/util/data/dname.c b/util/data/dname.c
index 10da71f6b4f06fc02412c2b69d1580abe53534a4..239a56ac1f284ac3c1db40e1c60959f3e8fe45f7 100644 (file)
--- a/util/data/dname.c
+++ b/util/data/dname.c
@@ -562,12 +562,20 @@ int
 dname_has_label(uint8_t* dname, size_t dnamelen, uint8_t* label)
 {
        size_t len = *dname;
-       while(*dname && len <= dnamelen) {
-               if(*dname == *label && memlowercmp(dname+1, label+1, *dname) == 0)
+       while(len <= dnamelen) {
+               if(!(*dname)) {
+                       if(*dname == *label)
+                               return 1; /* empty label match */
+                       /* termination label found, stop iterating */
+                       return 0;
+               }
+               if(*dname == *label && *label &&
+                       memlowercmp(dname+1, label+1, *dname) == 0)
                        return 1;
                len += *dname;
                dname += *dname;
                dname++;
+               len++;
        }
        return 0;
 }