diff --git a/bpf_progs/bpf_net_helpers.h b/bpf_progs/bpf_net_helpers.h
index 8754466..11d4bbf 100644
--- a/bpf_progs/bpf_net_helpers.h
+++ b/bpf_progs/bpf_net_helpers.h
@@ -34,6 +34,20 @@
 
 #include "bpf_helpers.h"
 
+// IP flags. (from kernel's include/net/ip.h)
+#define IP_CE      0x8000  // Flag: "Congestion" (really reserved 'evil bit')
+#define IP_DF      0x4000  // Flag: "Don't Fragment"
+#define IP_MF      0x2000  // Flag: "More Fragments"
+#define IP_OFFSET  0x1FFF  // "Fragment Offset" part
+
+// IPv6 fragmentation header. (from kernel's include/net/ipv6.h)
+struct frag_hdr {
+    __u8   nexthdr;
+    __u8   reserved;        // always zero
+    __be16 frag_off;        // 13 bit offset, 2 bits zero, 1 bit "More Fragments"
+    __be32 identification;
+};
+
 // Offsets from beginning of L4 (TCP/UDP) header
 #define TCP_OFFSET(field) offsetof(struct tcphdr, field)
 #define UDP_OFFSET(field) offsetof(struct udphdr, field)
diff --git a/bpf_progs/clatd.c b/bpf_progs/clatd.c
index 1dc727c..2555d94 100644
--- a/bpf_progs/clatd.c
+++ b/bpf_progs/clatd.c
@@ -21,20 +21,6 @@
 #include "clatd.h"
 #include "clat_mark.h"
 
-// IP flags. (from kernel's include/net/ip.h)
-#define IP_CE      0x8000  // Flag: "Congestion" (really reserved 'evil bit')
-#define IP_DF      0x4000  // Flag: "Don't Fragment"
-#define IP_MF      0x2000  // Flag: "More Fragments"
-#define IP_OFFSET  0x1FFF  // "Fragment Offset" part
-
-// from kernel's include/net/ipv6.h
-struct frag_hdr {
-    __u8   nexthdr;
-    __u8   reserved;        // always zero
-    __be16 frag_off;        // 13 bit offset, 2 bits zero, 1 bit "More Fragments"
-    __be32 identification;
-};
-
 DEFINE_BPF_MAP_GRW(clat_ingress6_map, HASH, ClatIngress6Key, ClatIngress6Value, 16, AID_SYSTEM)
 
 static inline __always_inline int nat64(struct __sk_buff* skb,
diff --git a/bpf_progs/offload.c b/bpf_progs/offload.c
index 211a111..d1cb9df 100644
--- a/bpf_progs/offload.c
+++ b/bpf_progs/offload.c
@@ -28,9 +28,6 @@
 #include "bpf_net_helpers.h"
 #include "offload.h"
 
-// From kernel:include/net/ip.h
-#define IP_DF 0x4000  // Flag: "Don't Fragment"
-
 // ----- Helper functions for offsets to fields -----
 
 // They all assume simple IP packets: