diff --git a/src/include/lwip/ip.h b/src/include/lwip/ip.h
index 6d4fbe3b..e2b090e1 100644
--- a/src/include/lwip/ip.h
+++ b/src/include/lwip/ip.h
@@ -116,7 +116,7 @@ struct ip_globals
 #endif /* LWIP_IPV4 */
 #if LWIP_IPV6
   /** Header of the input IPv6 packet currently being processed. */
-  const struct ip6_hdr *current_ip6_header;
+  struct ip6_hdr *current_ip6_header;
 #endif /* LWIP_IPV6 */
   /** Total header length of current_ip4/6_header (i.e. after this, the UDP/TCP header starts) */
   u16_t current_ip_header_tot_len;
@@ -152,7 +152,7 @@ extern struct ip_globals ip_data;
 /** Get the IPv6 header of the current packet.
  * This function must only be called from a receive callback (udp_recv,
  * raw_recv, tcp_accept). It will return NULL otherwise. */
-#define ip6_current_header()      ip_data.current_ip6_header
+#define ip6_current_header()      ((const struct ip6_hdr*)(ip_data.current_ip6_header))
 /** Returns TRUE if the current IP input packet is IPv6, FALSE if it is IPv4 */
 #define ip_current_is_v6()        (ip6_current_header() != NULL)
 /** Source IPv6 address of current_header */
@@ -194,13 +194,13 @@ extern struct ip_globals ip_data;
 /** Get the IPv6 header of the current packet.
  * This function must only be called from a receive callback (udp_recv,
  * raw_recv, tcp_accept). It will return NULL otherwise. */
-#define ip6_current_header()      ip_data.current_ip6_header
+#define ip6_current_header()      ((const struct ip6_hdr*)(ip_data.current_ip6_header))
 /** Always returns TRUE when only supporting IPv6 only */
 #define ip_current_is_v6()        1
 /** Get the transport layer protocol */
 #define ip_current_header_proto() IP6H_NEXTH(ip6_current_header())
 /** Get the transport layer header */
-#define ip_next_header_ptr()     ((const void*)((const u8_t*)ip6_current_header()))
+#define ip_next_header_ptr()     ((const void*)(((const u8_t*)ip6_current_header()) + ip_current_header_tot_len()))
 /** Source IP6 address of current_header */
 #define ip6_current_src_addr()    (&ip_data.current_iphdr_src)
 /** Destination IP6 address of current_header */
diff --git a/src/include/lwip/ip6_frag.h b/src/include/lwip/ip6_frag.h
index 1a666a8c..87e0e86a 100644
--- a/src/include/lwip/ip6_frag.h
+++ b/src/include/lwip/ip6_frag.h
@@ -90,7 +90,7 @@ extern "C" {
 struct ip6_reassdata {
   struct ip6_reassdata *next;
   struct pbuf *p;
-  const struct ip6_hdr *iphdr; /* pointer to the first (original) IPv6 header */
+  struct ip6_hdr *iphdr; /* pointer to the first (original) IPv6 header */
 #if IPV6_FRAG_COPYHEADER
   ip6_addr_p_t src; /* copy of the source address in the IP header */
   ip6_addr_p_t dest; /* copy of the destination address in the IP header */