test case ensures tag for caa is not blank

src/lib/ares_dns_parse.c

@@ -66,7 +66,8 @@ static ares_status_t ares_dns_parse_and_set_dns_str(ares__buf_t *buf,
                                                     size_t       max_len,
                                                     ares_bool_t  allow_multiple,
                                                     ares_dns_rr_t    *rr,
-                                                    ares_dns_rr_key_t key)
+                                                    ares_dns_rr_key_t key,
+                                                    ares_bool_t blank_allowed)
 {
   ares_status_t status;
   char         *str = NULL;
@@ -76,6 +77,11 @@ static ares_status_t ares_dns_parse_and_set_dns_str(ares__buf_t *buf,
     return status;
   }
 
+  if (!blank_allowed && ares_strlen(str) == 0) {
+    ares_free(str);
+    return ARES_EBADRESP;
+  }
+
   status = ares_dns_rr_set_str_own(rr, key, str);
   if (status != ARES_SUCCESS) {
     ares_free(str);
@@ -255,7 +261,7 @@ static ares_status_t ares_dns_parse_rr_hinfo(ares__buf_t   *buf,
   /* CPU */
   status = ares_dns_parse_and_set_dns_str(
     buf, ares_dns_rr_remaining_len(buf, orig_len, rdlength), ARES_FALSE, rr,
-    ARES_RR_HINFO_CPU);
+    ARES_RR_HINFO_CPU, ARES_TRUE);
   if (status != ARES_SUCCESS) {
     return status;
   }
@@ -263,7 +269,7 @@ static ares_status_t ares_dns_parse_rr_hinfo(ares__buf_t   *buf,
   /* OS */
   status = ares_dns_parse_and_set_dns_str(
     buf, ares_dns_rr_remaining_len(buf, orig_len, rdlength), ARES_FALSE, rr,
-    ARES_RR_HINFO_OS);
+    ARES_RR_HINFO_OS, ARES_TRUE);
 
   return status;
 }
@@ -360,7 +366,7 @@ static ares_status_t ares_dns_parse_rr_naptr(ares__buf_t   *buf,
   /* FLAGS */
   status = ares_dns_parse_and_set_dns_str(
     buf, ares_dns_rr_remaining_len(buf, orig_len, rdlength), ARES_FALSE, rr,
-    ARES_RR_NAPTR_FLAGS);
+    ARES_RR_NAPTR_FLAGS, ARES_TRUE);
   if (status != ARES_SUCCESS) {
     return status;
   }
@@ -368,7 +374,7 @@ static ares_status_t ares_dns_parse_rr_naptr(ares__buf_t   *buf,
   /* SERVICES */
   status = ares_dns_parse_and_set_dns_str(
     buf, ares_dns_rr_remaining_len(buf, orig_len, rdlength), ARES_FALSE, rr,
-    ARES_RR_NAPTR_SERVICES);
+    ARES_RR_NAPTR_SERVICES, ARES_TRUE);
   if (status != ARES_SUCCESS) {
     return status;
   }
@@ -376,7 +382,7 @@ static ares_status_t ares_dns_parse_rr_naptr(ares__buf_t   *buf,
   /* REGEXP */
   status = ares_dns_parse_and_set_dns_str(
     buf, ares_dns_rr_remaining_len(buf, orig_len, rdlength), ARES_FALSE, rr,
-    ARES_RR_NAPTR_REGEXP);
+    ARES_RR_NAPTR_REGEXP, ARES_TRUE);
   if (status != ARES_SUCCESS) {
     return status;
   }
@@ -656,7 +662,7 @@ static ares_status_t ares_dns_parse_rr_caa(ares__buf_t *buf, ares_dns_rr_t *rr,
   /* Tag */
   status = ares_dns_parse_and_set_dns_str(
     buf, ares_dns_rr_remaining_len(buf, orig_len, rdlength), ARES_FALSE, rr,
-    ARES_RR_CAA_TAG);
+    ARES_RR_CAA_TAG, ARES_FALSE);
   if (status != ARES_SUCCESS) {
     return status;
   }