From: Vladimír Čunát <vladimir.cunat@nic.cz>
Date: Wed, 1 Aug 2018 16:06:17 +0000 (+0200)
Subject: knot_dname_in_bailiwick(): new API
X-Git-Tag: v2.7.0~5^2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d55f160a96bbcfe36ee4e10a2211bee669e9f0df;p=thirdparty%2Fknot-dns.git

knot_dname_in_bailiwick(): new API

And reimplement knot_dname_is_sub() and knot_dname_in() via the new API.
---

diff --git a/src/libknot/dname.c b/src/libknot/dname.c
index d97bcd4efe..1a2790ea63 100644
--- a/src/libknot/dname.c
+++ b/src/libknot/dname.c
@@ -516,44 +516,6 @@ size_t knot_dname_realsize(const knot_dname_t *name, const uint8_t *pkt)
 	return len + 1;
 }
 
-_public_
-bool knot_dname_is_sub(const knot_dname_t *sub, const knot_dname_t *domain)
-{
-	if (sub == NULL || domain == NULL || sub == domain) {
-		return false;
-	}
-
-	/* Subdomain must have more labels than parent. */
-	size_t sub_l = knot_dname_labels(sub, NULL);
-	size_t domain_l = knot_dname_labels(domain, NULL);
-	if (sub_l <= domain_l) {
-		return false;
-	}
-
-	/* Align end-to-end to common suffix. */
-	int common = dname_align(&sub, sub_l, &domain, domain_l);
-
-	/* Compare common suffix. */
-	while (common > 0) {
-		/* Compare label. */
-		if (!label_is_equal(sub, domain)) {
-			return false;
-		}
-		/* Next label. */
-		sub = knot_wire_next_label(sub, NULL);
-		domain = knot_wire_next_label(domain, NULL);
-		--common;
-	}
-
-	return true;
-}
-
-_public_
-bool knot_dname_in(const knot_dname_t *domain, const knot_dname_t *sub)
-{
-	return knot_dname_is_equal(domain, sub) || knot_dname_is_sub(sub, domain);
-}
-
 _public_
 size_t knot_dname_matched_labels(const knot_dname_t *d1, const knot_dname_t *d2)
 {
@@ -772,3 +734,22 @@ uint8_t *knot_dname_lf(const knot_dname_t *src, knot_dname_storage_t storage)
 
 	return &storage[idx];
 }
+
+_public_
+int knot_dname_in_bailiwick(const knot_dname_t *name, const knot_dname_t *bailiwick)
+{
+	if (name == NULL || bailiwick == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	int label_diff = knot_dname_labels(name, NULL) - knot_dname_labels(bailiwick, NULL);
+	if (label_diff < 0) {
+		return KNOT_EOUTOFZONE;
+	}
+
+	for (int i = 0; i < label_diff; ++i) {
+		name = knot_wire_next_label(name, NULL);
+	}
+
+	return knot_dname_is_equal(name, bailiwick) ? label_diff : KNOT_EOUTOFZONE;
+}
diff --git a/src/libknot/dname.h b/src/libknot/dname.h
index b96e9095b7..e6e11afe49 100644
--- a/src/libknot/dname.h
+++ b/src/libknot/dname.h
@@ -189,30 +189,6 @@ size_t knot_dname_size(const knot_dname_t *name);
 _pure_
 size_t knot_dname_realsize(const knot_dname_t *name, const uint8_t *pkt);
 
-/*!
- * \brief Checks if one domain name is a (strict) subdomain of other.
- *
- * \param sub     Domain name to be the possible subdomain.
- * \param domain  Domain name to be the possible parent domain.
- *
- * \retval true \a sub is a (strict) subdomain of \a domain.
- * \retval false otherwise.
- */
-_pure_
-bool knot_dname_is_sub(const knot_dname_t *sub, const knot_dname_t *domain);
-
-/*!
- * \brief Check if the domain name is a subdomain of or equal to other.
- *
- * \param domain  Domain name to be the possible parent domain.
- * \param sub     Domain name to be the possible subdomain.
- *
- * \retval true \a sub us a subdomain or equal to \a domain.
- * \retval false otherwise.
- */
-_pure_
-bool knot_dname_in(const knot_dname_t *domain, const knot_dname_t *sub);
-
 /*!
  * \brief Checks if the domain name is a wildcard.
  *
@@ -338,4 +314,46 @@ size_t knot_dname_labels(const uint8_t *name, const uint8_t *pkt);
  */
 uint8_t *knot_dname_lf(const knot_dname_t *src, knot_dname_storage_t storage);
 
+/*!
+ * \brief Check whether a domain name is under another one and how deep.
+ *
+ * \param name       The longer name to check.
+ * \param bailiwick  The shorter name to check.
+ *
+ * \retval >=0 a subdomain nested this many labels.
+ * \retval <0 not a subdomain (KNOT_EOUTOFZONE) or another error (KNOT_EINVAL).
+ */
+int knot_dname_in_bailiwick(const knot_dname_t *name, const knot_dname_t *bailiwick);
+
+/*!
+ * \brief Checks if one domain name is a (strict) subdomain of other.
+ *
+ * \param sub     Domain name to be the possible subdomain.
+ * \param domain  Domain name to be the possible parent domain.
+ *
+ * \retval true \a sub is a (strict) subdomain of \a domain.
+ * \retval false otherwise.
+ */
+static inline
+bool knot_dname_is_sub(const knot_dname_t *sub, const knot_dname_t *domain)
+{
+	return knot_dname_in_bailiwick(sub, domain) > 0;
+}
+
+/*!
+ * \brief Check if the domain name is a subdomain of or equal to other.
+ *
+ * \param domain  Domain name to be the possible parent domain.
+ * \param sub     Domain name to be the possible subdomain.
+ *
+ * \retval true \a sub us a subdomain or equal to \a domain.
+ * \retval false otherwise.
+ */
+static inline
+bool knot_dname_in(const knot_dname_t *domain, const knot_dname_t *sub)
+{
+	return knot_dname_in_bailiwick(sub, domain) >= 0;
+}
+
+
 /*! @} */