Carry split and detection functions to separate file

This needed to escape code duplication in further development of kernel
module. Also this cleanups the code.

mangle.h

@@ -0,0 +1,63 @@
+#ifndef YU_MANGLE_H
+#define YU_MANGLE_H
+#define RAWSOCKET_MARK 0xfc70
+
+#ifdef KERNEL_SPACE
+#include <linux/types.h>
+typedef __u8 uint8_t;
+typedef __u32 uint32_t;
+
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/stddef.h>
+#include <linux/net.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/tcp.h>
+
+#include <asm/byteorder.h>
+#define ntohs(x) __constant_ntohs(x)
+#define ntohl(x) __constant_ntohl(x)
+#define htons(x) __constant_htons(x)
+#define htonl(x) __constant_htonl(x)
+
+#define	IP_RF 0x8000			/* reserved fragment flag */
+#define	IP_DF 0x4000			/* dont fragment flag */
+#define	IP_MF 0x2000			/* more fragments flag */
+#define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
+#else
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+#include <arpa/inet.h>
+#include <netinet/ip.h>
+#include <netinet/tcp.h>
+#endif
+
+struct verdict {
+	int gvideo_hello; /* google video hello packet */
+	int sni_offset; /* offset from start of tcp _payload_ */
+	int sni_len;
+};
+
+struct verdict analyze_tls_data(const uint8_t *data, uint32_t dlen);
+
+int ip4_frag(const uint8_t *pkt, uint32_t pktlen, 
+			uint32_t payload_offset, 
+			uint8_t *frag1, uint32_t *f1len, 
+			uint8_t *frag2, uint32_t *f2len);
+
+int tcp4_frag(const uint8_t *pkt, uint32_t pktlen, 
+			uint32_t payload_offset, 
+			uint8_t *seg1, uint32_t *s1len, 
+			uint8_t *seg2, uint32_t *s2len);
+
+int ip4_payload_split(uint8_t *pkt, uint32_t buflen,
+		       struct iphdr **iph, uint32_t *iph_len, 
+		       uint8_t **payload, uint32_t *plen);
+
+int tcp4_payload_split(uint8_t *pkt, uint32_t buflen,
+		       struct iphdr **iph, uint32_t *iph_len,
+		       struct tcphdr **tcph, uint32_t *tcph_len,
+		       uint8_t **payload, uint32_t *plen);
+#endif /* YU_MANGLE_H */