From ebb519919ae63d23f5630695f3af61956aeb40c7 Mon Sep 17 00:00:00 2001
From: Willem Toorop <willem@nlnetlabs.nl>
Date: Thu, 12 Mar 2015 23:09:04 +0100
Subject: [PATCH] Get rid of ldns usage, and a malloc/free

---
 src/general.c       | 55 ++++++++++++++++++++++++++++++++++++++++++---
 src/util-internal.c | 32 --------------------------
 src/util-internal.h |  1 -
 3 files changed, 52 insertions(+), 36 deletions(-)

diff --git a/src/general.c b/src/general.c
index 8531b78f..dc81b8f1 100644
--- a/src/general.c
+++ b/src/general.c
@@ -286,7 +286,7 @@ priv_getdns_hostname_loop(getdns_context *context, getdns_eventloop *loop,
 	struct getdns_bindata *address_data;
 	struct getdns_bindata *address_type;
 	uint16_t req_type;
-	char *name;
+	char name[1024];
 	getdns_return_t retval;
 
 	if ((retval =
@@ -308,11 +308,60 @@ priv_getdns_hostname_loop(getdns_context *context, getdns_eventloop *loop,
 		req_type = GETDNS_RRTYPE_PTR;
 	else
 		return GETDNS_RETURN_INVALID_PARAMETER;
-	if ((name = reverse_address(address_data)) == NULL)
+
+	switch (address_data->size) {
+	case 4:
+		(void)snprintf(name, sizeof(name),
+		    "%hhu.%hhu.%hhu.%hhu.in-addr.arpa.",
+		    ((uint8_t *)address_data->data)[3],
+		    ((uint8_t *)address_data->data)[2],
+		    ((uint8_t *)address_data->data)[1],
+		    ((uint8_t *)address_data->data)[0]);
+		break;
+	case 16:
+		(void)snprintf(name, sizeof(name),
+		    "%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx."
+		    "%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx."
+		    "%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx."
+		    "%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.ip6.arpa.",
+		    ((uint8_t *)address_data->data)[15] & 0x0F,
+		    ((uint8_t *)address_data->data)[15] >> 4,
+		    ((uint8_t *)address_data->data)[14] & 0x0F,
+		    ((uint8_t *)address_data->data)[14] >> 4,
+		    ((uint8_t *)address_data->data)[13] & 0x0F,
+		    ((uint8_t *)address_data->data)[13] >> 4,
+		    ((uint8_t *)address_data->data)[12] & 0x0F,
+		    ((uint8_t *)address_data->data)[12] >> 4,
+		    ((uint8_t *)address_data->data)[11] & 0x0F,
+		    ((uint8_t *)address_data->data)[11] >> 4,
+		    ((uint8_t *)address_data->data)[10] & 0x0F,
+		    ((uint8_t *)address_data->data)[10] >> 4,
+		    ((uint8_t *)address_data->data)[9] & 0x0F,
+		    ((uint8_t *)address_data->data)[9] >> 4,
+		    ((uint8_t *)address_data->data)[8] & 0x0F,
+		    ((uint8_t *)address_data->data)[8] >> 4,
+		    ((uint8_t *)address_data->data)[7] & 0x0F,
+		    ((uint8_t *)address_data->data)[7] >> 4,
+		    ((uint8_t *)address_data->data)[6] & 0x0F,
+		    ((uint8_t *)address_data->data)[6] >> 4,
+		    ((uint8_t *)address_data->data)[5] & 0x0F,
+		    ((uint8_t *)address_data->data)[5] >> 4,
+		    ((uint8_t *)address_data->data)[4] & 0x0F,
+		    ((uint8_t *)address_data->data)[4] >> 4,
+		    ((uint8_t *)address_data->data)[3] & 0x0F,
+		    ((uint8_t *)address_data->data)[3] >> 4,
+		    ((uint8_t *)address_data->data)[2] & 0x0F,
+		    ((uint8_t *)address_data->data)[2] >> 4,
+		    ((uint8_t *)address_data->data)[1] & 0x0F,
+		    ((uint8_t *)address_data->data)[1] >> 4,
+		    ((uint8_t *)address_data->data)[0] & 0x0F,
+		    ((uint8_t *)address_data->data)[0] >> 4);
+		break;
+	default:
 		return GETDNS_RETURN_INVALID_PARAMETER;
+	}
 	retval = priv_getdns_general_loop(context, loop, name, req_type,
 	    extensions, userarg, transaction_id, callback);
-	free(name);
 	return retval;
 }				/* getdns_hostname_loop */
 
diff --git a/src/util-internal.c b/src/util-internal.c
index bbbfd4da..98596c62 100644
--- a/src/util-internal.c
+++ b/src/util-internal.c
@@ -848,38 +848,6 @@ error_free_result:
 	return NULL;
 }
 
-/**
- * reverse an IP address for PTR lookup
- * @param address_data IP address to reverse
- * @return NULL on allocation failure
- * @return reversed string on success, caller must free storage via call to free()
- */
-char *
-reverse_address(struct getdns_bindata *address_data)
-{
-	ldns_rdf *addr_rdf;
-	ldns_rdf *rev_rdf;
-	char *rev_str;
-
-	if (address_data->size == 4)
-		addr_rdf = ldns_rdf_new(LDNS_RDF_TYPE_A, 4, address_data->data);
-	else if (address_data->size == 16)
-		addr_rdf = ldns_rdf_new(LDNS_RDF_TYPE_AAAA, 16, address_data->data);
-	else
-		return NULL;
-	if (!addr_rdf)
-		return NULL;
-
-	rev_rdf = ldns_rdf_address_reverse(addr_rdf);
-	ldns_rdf_free(addr_rdf);
-	if (!rev_rdf)
-		return NULL;
-
-	rev_str = ldns_rdf2str(rev_rdf);
-	ldns_rdf_deep_free(rev_rdf);
-	return rev_str;
-}
-
 static int
 extformatcmp(const void *a, const void *b)
 {
diff --git a/src/util-internal.h b/src/util-internal.h
index 07aa68d2..e469fae8 100644
--- a/src/util-internal.h
+++ b/src/util-internal.h
@@ -122,7 +122,6 @@ getdns_return_t sockaddr_to_dict(struct getdns_context *context,
 
 struct getdns_dns_req;
 struct getdns_dict *create_getdns_response(struct getdns_dns_req *completed_request);
-char *reverse_address(struct getdns_bindata *address_data);
 
 getdns_return_t validate_dname(const char* dname);