Add functions to extract RFC 8914 extended errors

edns.c

@@ -10,6 +10,7 @@
  * See the file LICENSE for the license
  */
 
+#include <ldns/config.h>
 #include <ldns/ldns.h>
 
 #define LDNS_OPTIONLIST_INIT 8
@@ -41,6 +42,44 @@ ldns_edns_get_data(const ldns_edns_option *edns)
 	return edns->_data;
 }
 
+ldns_status 
+ldns_edns_ede_get_code(const ldns_edns_option *edns, uint16_t *ede_code)
+{
+	assert(edns != NULL);
+	assert(ede_code != NULL);
+
+	if (edns->_code != LDNS_EDNS_EDE) return LDNS_STATUS_NOT_EDE;
+
+	if (edns->_size < 2) return LDNS_STATUS_EDE_OPTION_MALFORMED;
+
+	*ede_code = (uint16_t) ntohs(*((uint16_t*) edns->_data));
+
+	return LDNS_STATUS_OK;
+}
+
+ldns_status 
+ldns_edns_ede_get_text(const ldns_edns_option* edns, char **ede_text)
+{
+	assert(edns != NULL);
+	assert(ede_text != NULL);
+
+	if (edns->_code != LDNS_EDNS_EDE) return LDNS_STATUS_NOT_EDE;
+
+	if (edns->_size < 2) return LDNS_STATUS_EDE_OPTION_MALFORMED;
+
+	*ede_text = NULL;
+
+	if (edns->_size > 2)
+	{
+		*ede_text = (char*) malloc((edns->_size - 1) * sizeof(char));
+
+		memset(*ede_text, 0, edns->_size - 1);
+		memcpy(*ede_text, &edns->_data[2], edns->_size - 2);
+	}
+
+	return LDNS_STATUS_OK;
+}
+
 ldns_buffer *
 ldns_edns_get_wireformat_buffer(const ldns_edns_option *edns)
 {

ldns/edns.h

@@ -140,6 +140,21 @@ ldns_edns_option_code ldns_edns_get_code(const ldns_edns_option *edns);
  */
 uint8_t *ldns_edns_get_data(const ldns_edns_option *edns);
 
+/**
+ * extract the RFC 8914 extended error code value.
+ * \param[in] *edns the EDNS option to extract the extended error code from
+ * \param[inout] *ede_code pointer to an uint16_t in which to store the extended error code
+ * \return LDNS_STATUS_OK or an ldns_status message with the error (LDNS_STATUS_NOT_EDE or LDNS_STATUS_EDE_OPTION_MALFORMED)
+ */
+ldns_status ldns_edns_ede_get_code(const ldns_edns_option *edns, uint16_t *ede_code);
+
+/**
+ * extract the optional RFC 8914 extended error code text.
+ * \param[in] *edns the EDNS option to extract the extended error code from
+ * \param[inout] **ede_text pointer to a char* in which to store the extended error text; allocated buffer must be freed by the caller, assigns NULL if no text was provided in the EDNS option
+ * \return LDNS_STATUS_OK or an ldns_status message with the error (LDNS_STATUS_NOT_EDE or LDNS_STATUS_EDE_OPTION_MALFORMED)
+ */
+ldns_status ldns_edns_ede_get_text(const ldns_edns_option* edns, char **ede_text);
 
 /**
  * serialise the EDNS option into wireformat.

ldns/error.h

@@ -141,7 +141,9 @@ enum ldns_enum_status {
 	LDNS_STATUS_RESERVED_SVCPARAM_KEY,
 	LDNS_STATUS_NO_SVCPARAM_VALUE_EXPECTED,
 	LDNS_STATUS_SVCPARAM_KEY_MORE_THAN_ONCE,
-	LDNS_STATUS_INVALID_SVCPARAM_VALUE
+	LDNS_STATUS_INVALID_SVCPARAM_VALUE,
+	LDNS_STATUS_NOT_EDE,
+	LDNS_STATUS_EDE_OPTION_MALFORMED
 };
 typedef enum ldns_enum_status ldns_status;