/*
 * network.h
 *
 *  Created on: Jul 29, 2017
 *      Author: wangyu
 */

#ifndef UDP2RAW_NETWORK_H_
#define UDP2RAW_NETWORK_H_

extern int raw_recv_fd;
extern int raw_send_fd;
extern int use_tcp_dummy_socket;
extern int seq_mode;
extern int max_seq_mode;
extern int filter_port;
// extern u32_t bind_address_uint32;
extern int disable_bpf_filter;

extern int lower_level;
extern int lower_level_manual;
extern char if_name[100];
extern char dev[100];
extern unsigned char dest_hw_addr[];

extern int random_drop;

extern int ifindex;

extern char g_packet_buf[huge_buf_len];
extern int g_packet_buf_len;
extern int g_packet_buf_cnt;
#ifdef UDP2RAW_MP
extern queue_t my_queue;

extern ev_async async_watcher;
extern struct ev_loop *g_default_loop;

extern pthread_mutex_t queue_mutex;
extern int use_pcap_mutex;

extern int pcap_cnt;

extern int pcap_link_header_len;

extern int send_with_pcap;
extern int pcap_header_captured;
extern int pcap_header_buf[buf_len];

struct icmphdr {
    uint8_t type;
    uint8_t code;
    uint16_t check_sum;
    uint16_t id;
    uint16_t seq;
};
#endif

struct my_iphdr {
#ifdef UDP2RAW_LITTLE_ENDIAN
    unsigned char ihl : 4;
    unsigned char version : 4;
#else
    unsigned char version : 4;
    unsigned char ihl : 4;
#endif
    u_int8_t tos;
    u_int16_t tot_len;
    u_int16_t id;
    u_int16_t frag_off;
    u_int8_t ttl;
    u_int8_t protocol;
    u_int16_t check;
    u_int32_t saddr;
    u_int32_t daddr;
    /*The options start here. */
};

struct my_udphdr {
    /*__extension__*/ union {
        struct
        {
            u_int16_t uh_sport; /* source port */
            u_int16_t uh_dport; /* destination port */
            u_int16_t uh_ulen;  /* udp length */
            u_int16_t uh_sum;   /* udp checksum */
        };
        struct
        {
            u_int16_t source;
            u_int16_t dest;
            u_int16_t len;
            u_int16_t check;
        };
    };
};

struct my_tcphdr {
    /*__extension__*/ union {
        struct
        {
            u_int16_t th_sport; /* source port */
            u_int16_t th_dport; /* destination port */
            u_int32_t th_seq;   /* sequence number */
            u_int32_t th_ack;   /* acknowledgement number */
#ifdef UDP2RAW_LITTLE_ENDIAN
            u_int8_t th_x2 : 4;  /* (unused) */
            u_int8_t tc_off : 4; /* data offset */
#else
            u_int8_t th_off : 4; /* data offset */
            u_int8_t th_x2 : 4;  /* (unused) */
#endif
            u_int8_t th_flags;
#define TH_FIN 0x01
#define TH_SYN 0x02
#define TH_RST 0x04
#define TH_PUSH 0x08
#define TH_ACK 0x10
#define TH_URG 0x20
            u_int16_t th_win; /* window */
            u_int16_t th_sum; /* checksum */
            u_int16_t th_urp; /* urgent pointer */
        };
        struct
        {
            u_int16_t source;
            u_int16_t dest;
            u_int32_t seq;
            u_int32_t ack_seq;
#ifdef UDP2RAW_LITTLE_ENDIAN
            u_int16_t res1 : 4;
            u_int16_t doff : 4;
            u_int16_t fin : 1;
            u_int16_t syn : 1;
            u_int16_t rst : 1;
            u_int16_t psh : 1;
            u_int16_t ack : 1;
            u_int16_t urg : 1;
            u_int16_t res2 : 2;
#else
            u_int16_t doff : 4;
            u_int16_t res1 : 4;
            u_int16_t res2 : 2;
            u_int16_t urg : 1;
            u_int16_t ack : 1;
            u_int16_t psh : 1;
            u_int16_t rst : 1;
            u_int16_t syn : 1;
            u_int16_t fin : 1;
#endif
            u_int16_t window;
            u_int16_t check;
            u_int16_t urg_ptr;
        };
    };
};

struct my_ip6hdr {
#ifdef UDP2RAW_LITTLE_ENDIAN
    uint8_t traffic_class_high : 4;
    uint8_t version : 4;
    uint8_t flow_label_high : 4;
    uint8_t traffic_class_low : 4;
#else
    uint8_t version : 4;
    uint8_t traffic_class_high : 4;
    uint8_t traffic_class_low : 4;
    uint8_t flow_label_high : 4;
#endif
    u_int16_t flow_label_low;
    u_int16_t payload_len;
    uint8_t next_header;
    uint8_t hop_limit;

    struct in6_addr src;
    struct in6_addr dst;
};

struct my_icmphdr {
    uint8_t type;
    uint8_t code;
    uint16_t check_sum;
    uint16_t id;
    uint16_t seq;
};

struct pseudo_header {
    u_int32_t source_address;
    u_int32_t dest_address;
    u_int8_t placeholder;
    u_int8_t protocol;
    u_int16_t tcp_length;
};

struct pseudo_header6 {
    struct in6_addr src;
    struct in6_addr dst;
    u_int32_t tcp_length;
    u_int16_t placeholder1;
    u_int8_t placeholder2;
    u_int8_t next_header;
};

struct packet_info_t  // todo change this to union
{
    uint8_t protocol;

    // u32_t src_ip;
    // u32_t dst_ip;
    my_ip_t new_src_ip;
    my_ip_t new_dst_ip;

    uint16_t src_port;
    uint16_t dst_port;

    // tcp_part:
    bool syn, ack, psh, rst;

    u32_t seq, ack_seq;

    u32_t ack_seq_counter;

    u32_t ts, ts_ack;

    uint16_t my_icmp_seq;

    bool has_ts;

    i32_t data_len;

#ifdef UDP2RAW_LINUX
    sockaddr_ll addr_ll;
#endif

    packet_info_t();
};

struct raw_info_t {
    packet_info_t send_info;
    packet_info_t recv_info;
    // int last_send_len;
    // int last_recv_len;
    bool peek = 0;
    // bool csum=1;
    u32_t reserved_send_seq;
    // uint32_t first_seq,first_ack_seq;
    int rst_received = 0;
    bool disabled = 0;

};  // g_raw_info;

int init_raw_socket();

void init_filter(int port);

void remove_filter();

#ifdef UDP2RAW_LINUX
int init_ifindex(const char *if_name, int fd, int &index);
#endif

#ifdef UDP2RAW_MP
int init_ifindex(const char *if_name, int &index);
#endif

int find_lower_level_info(u32_t ip, u32_t &dest_ip, string &if_name, string &hw);

int get_src_adress(u32_t &ip, u32_t remote_ip_uint32, int remote_port);  // a trick to get src adress for a dest adress,so that we can use the src address in raw socket as source ip
int get_src_adress2(address_t &output_addr, address_t remote_addr);

int try_to_list_and_bind(int &bind_fd, u32_t local_ip_uint32, int port);  // try to bind to a port,may fail.
int try_to_list_and_bind2(int &fd, address_t address);

int client_bind_to_a_new_port(int &bind_fd, u32_t local_ip_uint32);  // find a free port and bind to it.
int client_bind_to_a_new_port2(int &fd, const address_t &address);

int discard_raw_packet();
int pre_recv_raw_packet();

int send_raw_ip(raw_info_t &raw_info, const char *payload, int payloadlen);

int peek_raw(raw_info_t &peek_info);

int recv_raw_ip(raw_info_t &raw_info, char *&payload, int &payloadlen);

int send_raw_icmp(raw_info_t &raw_info, const char *payload, int payloadlen);

int send_raw_udp(raw_info_t &raw_info, const char *payload, int payloadlen);

int send_raw_tcp(raw_info_t &raw_info, const char *payload, int payloadlen);

int recv_raw_icmp(raw_info_t &raw_info, char *&payload, int &payloadlen);

int recv_raw_udp(raw_info_t &raw_info, char *&payload, int &payloadlen);

int recv_raw_tcp(raw_info_t &raw_info, char *&payload, int &payloadlen);

// int send_raw(raw_info_t &raw_info,const char * payload,int payloadlen);

// int recv_raw(raw_info_t &raw_info,char * &payload,int &payloadlen);

int send_raw0(raw_info_t &raw_info, const char *payload, int payloadlen);

int recv_raw0(raw_info_t &raw_info, char *&payload, int &payloadlen);

int after_send_raw0(raw_info_t &raw_info);

int after_recv_raw0(raw_info_t &raw_info);

#endif /* NETWORK_H_ */