dhcp.h

#ifndef DHCP_H
#define DHCP_H

#include <stdint.h>

enum ports {
    BOOTPS = 67,
    BOOTPC = 68
};

enum op_types {
    BOOTREQUEST = 1,
    BOOTREPLY   = 2,   
};

enum hardware_address_types {
    ETHERNET     = 0x01,
    ETHERNET_LEN = 0x06,
};

/* DHCP message */

enum {
    DHCP_HEADER_SIZE = 236 // without size of options
};

struct dhcp_message {
    uint8_t op;      // message op code, message type
    uint8_t htype;   // hardware address type
    uint8_t hlen;    // hardware address length
    uint8_t hops;    // incremented by relay agents

    uint32_t xid;    // transaction ID

    uint16_t secs;   // seconds since address acquisition or renewal
    uint16_t flags;  // flags

    uint32_t ciaddr; // client IP address
    uint32_t yiaddr; // 'your' client IP address
    uint32_t siaddr; // IP address of the next server to use in bootstrap
    uint32_t giaddr; // relay agent IP address

    uint8_t chaddr[16]; // client hardware address

    uint8_t sname[64]; // server host name

    uint8_t file[128]; // boot file name

    uint8_t options[312]; // optional parameters field
};

typedef struct dhcp_message dhcp_message;

#endif