#ifndef DNS_ANALYSE_H
#define DNS_ANALYSE_H

#include <MESA/cJSON.h>

#ifndef u_char
#define u_char unsigned char
#endif

#ifndef u_int16_t
#define u_int16_t unsigned short
#endif

#ifndef u_int32_t
#define u_int32_t unsigned int //adjust by lqy 20070521 long to int
#endif

#ifndef MIN
#define MIN(a, b) ((a) > (b) ? (b) : (a))
#endif

#define DNS_MAX_SALT        256
#define DNS_MAX_OWNER       256
#define DNS_MAX_MAPS        256
#define DNS_MAX_PUBLIC_KEY  256
#define DNS_MAX_SIGNER_NAME 256
#define DNS_MAX_SIGNATURE   256
#define DNS_MAX_DIGEST      256
#define DNS_MAX_TARGET      256

#define DNS_HINFO_MAX_CPU   40
#define DNS_HINFO_MAX_OS    40
#define DNS_MAX_NAME        255

#define DNS_RR_TYPE_ALL  0
#define DNS_RR_TYPE_ANS  1
#define DNS_RR_TYPE_AUTH 2
#define DNS_RR_TYPE_ADD  3

#define NS_INT8SZ  1
#define NS_INT16SZ 2
#define NS_INT32SZ 4

#define NS_GET32(l, cp)                                                                                                   \
	do                                                                                                                    \
	{                                                                                                                     \
		register u_char *t_cp = (u_char *)(cp);                                                                           \
		(l) = ((u_int32_t)t_cp[0] << 24) | ((u_int32_t)t_cp[1] << 16) | ((u_int32_t)t_cp[2] << 8) | ((u_int32_t)t_cp[3]); \
		(cp) += NS_INT32SZ;                                                                                               \
	} while (0)

#define NS_GET16(s, cp)                                         \
	do                                                          \
	{                                                           \
		register u_char *t_cp = (u_char *)(cp);                 \
		(s) = ((u_int16_t)t_cp[0] << 8) | ((u_int16_t)t_cp[1]); \
		(cp) += NS_INT16SZ;                                     \
	} while (0)

#define NS_GET8(s, cp)                          \
	do                                          \
	{                                           \
		register u_char *t_cp = (u_char *)(cp); \
		(s) = ((u_char)t_cp[0]);                \
		(cp) += NS_INT8SZ;                      \
	} while (0)

#define NS_SET8(data, payload, used_len)                         \
	do                                                           \
	{                                                            \
		u_char seg_8 = (data);                                   \
		memcpy(((payload) + (used_len)), &seg_8, sizeof(seg_8)); \
		(used_len) += sizeof(seg_8);                             \
	} while (0)

#define NS_SET16(data, payload, used_len)                          \
	do                                                             \
	{                                                              \
		u_int16_t seg_16 = htons(data);                            \
		memcpy(((payload) + (used_len)), &seg_16, sizeof(seg_16)); \
		(used_len) += sizeof(seg_16);                              \
	} while (0)

#define NS_SET32(data, payload, used_len)                          \
	do                                                             \
	{                                                              \
		u_int32_t seg_32 = htonl(data);                            \
		memcpy(((payload) + (used_len)), &seg_32, sizeof(seg_32)); \
		(used_len) += sizeof(seg_32);                              \
	} while (0)

#define NS_SETLEN(data, len, payload, used_len)           \
	do                                                    \
	{                                                     \
		memcpy(((payload) + (used_len)), (data), (len)); \
		(used_len) += (len);                              \
	} while (0)

/* RR type */
#define DNS_TYPE_A          1
#define DNS_TYPE_NS         2
#define DNS_TYPE_MD         3
#define DNS_TYPE_MF         4
#define DNS_TYPE_CNAME      5
#define DNS_TYPE_SOA        6
#define DNS_TYPE_MB         7
#define DNS_TYPE_MG         8
#define DNS_TYPE_MR         9
#define DNS_TYPE_NULL       10
#define DNS_TYPE_WKS        11
#define DNS_TYPE_PTR        12
#define DNS_TYPE_HINFO      13
#define DNS_TYPE_MINFO      14
#define DNS_TYPE_MX         15
#define DNS_TYPE_TXT        16
#define DNS_TYPE_RP         17
#define DNS_TYPE_ISDN       20
#define DNS_TYPE_AAAA       28
#define DNS_TYPE_SRV        33
#define DNS_TYPE_DNAME      39
#define DNS_TYPE_OPT        41
#define DNS_TYPE_DS         43
#define DNS_TYPE_RRSIG      46
#define DNS_TYPE_NSEC       47
#define DNS_TYPE_DNSKEY     48
#define DNS_TYPE_NSEC3      50
#define DNS_TYPE_NSEC3PARAM 51
#define DNS_QTYPE_AXFR      252
#define DNS_QTYPE_MAILB     253
#define DNS_QTYPE_MAILA     254
#define DNS_QTYPE_ANY       255
#define DNS_TYPE_DLV        32769 /* DSNSEC Lokkaside Validation */
#define DNS_TYPE_UNKNOWN    65534

#define DNS_CLASS_UNKNOWN 0
#define DNS_CLASS_IN      1
#define DNS_CLASS_CS      2
#define DNS_CLASS_CH      3
#define DNS_CLASS_HS      4
#define DNS_QCLASS_ANY    255

// 存储 DNS 头部信息的结构体
typedef struct _dns_hdr
{
	u_int16_t id;
#if __BYTE_ORDER == __LITTLE_ENDIAN
	u_char rd : 1;
	u_char tc : 1;
	u_char aa : 1;
	u_char opcode : 4;
	u_char qr : 1;
	u_char rcode : 4;
	u_char z : 3;
	u_char ra : 1;
#elif __BYTE_ORDER == __BIG_ENDIAN
	u_char qr : 1;
	u_char opcode : 4;
	u_char aa : 1;
	u_char tc : 1;
	u_char rd : 1;
	u_char ra : 1;
	u_char z : 3;
	u_char rcode : 4;
#endif
	u_int16_t qdcount;
	u_int16_t ancount;
	u_int16_t aucount; //authority count
	u_int16_t adcount; //additional count
} dns_hdr_t;

typedef struct _hinfo
{
	u_char os_len;
	u_char cpu_len;
	u_char cpu[DNS_HINFO_MAX_CPU + 1];
	u_char os[DNS_HINFO_MAX_OS + 1];
} hinfo_t;

typedef struct _minfo
{
	u_char rmailbx[DNS_MAX_NAME + 1];
	u_char emailbx[DNS_MAX_NAME + 1];
} minfo_t;

typedef struct _mx
{
	u_int16_t preference;
	u_char exchange[DNS_MAX_NAME + 1];
} mx_t;

typedef struct _soa
{
	u_char mname[DNS_MAX_NAME + 1];
	u_char rname[DNS_MAX_NAME + 1];
	u_int32_t serial;
	u_int32_t refresh;
	u_int32_t retry;
	u_int32_t expire;
	u_int32_t minimum;
} soa_t;

typedef struct _rp_t
{
	u_char mailbox[DNS_MAX_NAME + 1];
	u_char txt_rr[DNS_MAX_NAME + 1];
} rp_t;

typedef struct _txt_t
{
	u_char txt[DNS_MAX_NAME + 1];
	u_char size;
} txt_t;

typedef struct _null
{
	u_char null[DNS_MAX_NAME + 1];
	u_char size;
} null_t;

typedef struct _wks
{
	u_char protocol;
	u_int32_t addr;
	u_int32_t size;
	u_char *bitmap;
} wks_t;

typedef struct _srv
{
	u_int16_t priority;
	u_int16_t weight;
	u_int16_t port;
	u_char target[DNS_MAX_TARGET];
} srv_t;

typedef struct _ds
{
	u_int16_t key_tag;
	u_char algo;
	u_char digest_type;
	u_int32_t digest_len;
	u_char *digest;
} ds_t;

typedef struct _rrsig
{
	u_int16_t type_covered;
	u_char algo;
	u_char labels;
	u_int32_t original_ttl;
	u_int32_t sig_expiration;
	u_int32_t sig_inception;
	u_int32_t key_tag;
	u_int32_t signature_len;
	u_char signer_name[DNS_MAX_SIGNER_NAME];
	u_char *signature;
} rrsig_t;

typedef struct _nsec
{
	u_int16_t maps_temp_len;
	u_int16_t maps_len;
	u_char next_domain[DNS_MAX_OWNER];
	u_char type_bit_maps[DNS_MAX_MAPS];
} nsec_t;

typedef struct _dnskey
{
	u_int16_t flags;
	u_char protocol;
	u_char algo;
	u_int32_t public_key_len;
	u_char *public_key;
} dnskey_t;

typedef struct _nsec3
{
	u_char hash_algo;
	u_char flags;
	u_char salt_len;
	u_char hash_len;
	u_int16_t iteration;
	u_int16_t maps_temp_len;
	u_int16_t maps_len;
	u_char *salt_value;
	u_char *next_hash_owner;
	u_char type_bit_maps[DNS_MAX_MAPS];
} nsec3_t;

typedef struct _nsec3param
{
	u_char hash_algo;
	u_char flags;
	u_char salt_len;
	u_int16_t iteration;
	u_char *salt_value;
} nsec3param_t;

// 存储 DNS 资源记录区域(回答区域 / 授权区域 / 附加区域)的结构体
typedef struct _dns_rr
{
	u_char name[DNS_MAX_NAME + 1];
	u_int16_t type;
	u_int16_t rr_class;
	u_int32_t ttl; /* 1byte: extended RCODE; 1byte: version; 2bytes: Z(upper bit) if type is OPT */
	u_int16_t rdlength;
	union {
		u_char cname[DNS_MAX_NAME + 1]; /* cname[DNS_MAX_NAME + 1]; */
		hinfo_t hinfo;
		u_char mb[DNS_MAX_NAME + 1]; /* mb[DNS_MAX_NAME + 1]; */
		u_char md[DNS_MAX_NAME + 1]; /* md[DNS_MAX_NAME + 1]; */
		u_char mf[DNS_MAX_NAME + 1]; /* mf[DNS_MAX_NAME + 1]; */
		u_char mg[DNS_MAX_NAME + 1]; /* mg[DNS_MAX_NAME + 1]; */
		minfo_t minfo;
		u_char mr[DNS_MAX_NAME + 1]; /* mr[DNS_MAX_NAME + 1]; */
		mx_t mx;
		u_char ns[DNS_MAX_NAME + 1];  /* ns[DNS_MAX_NAME + 1]; */
		u_char ptr[DNS_MAX_NAME + 1]; /* ptr[DNS_MAX_NAME + 1]; */
		soa_t soa;
		u_char a[DNS_MAX_NAME + 1];
		u_char aaaa[DNS_MAX_NAME + 1]; /* aaaa[16]; */
		u_char dname[DNS_MAX_NAME + 1];
		u_char isdn[DNS_MAX_NAME + 1];
		u_char unknown_data[DNS_MAX_NAME + 1];
		txt_t txt;
		rp_t rp;
		null_t null;
		wks_t wks;
		srv_t srv;
		ds_t ds;
		rrsig_t rrsig;
		nsec_t nsec;
		dnskey_t dnskey;
		nsec3_t nsec3;
		nsec3param_t nsec3param;
	} rdata;
} dns_rr_t;

typedef struct _fake_packet_opt
{
	u_int16_t cfg_type; /* IP or STR */
	u_int16_t res_type;
	u_int32_t ttl;
	u_int32_t res_len;
	u_char res_info[DNS_MAX_NAME + 1];
} cheat_pkt_opt_t;

// 存储 DNS Queries 区域的结构体
typedef struct
{
	u_int16_t qtype;
	u_int16_t qclass;
	u_char qname[DNS_MAX_NAME + 1];
} dns_query_question_t;

#define MAX_RR_NUM 256

// 存储完整 DNS 信息的结构体
typedef struct _dns_info
{
	// 存储 DNS 头部信息的结构体
	dns_hdr_t hdr_info;

	// RR 记录的个数
	int rr_count;
	// 存储 DNS 资源记录区域(回答区域 / 授权区域 / 附加区域)的结构体
	dns_rr_t rr[MAX_RR_NUM];

	// 存储 DNS Queries 区域的结构体
	dns_query_question_t query_question;
} dns_info_t;

#ifdef __cplusplus
extern "C"
{
#endif

dns_info_t *dns_new(void);
void dns_free(dns_info_t *dns_info);

int dns_parser(dns_info_t *dns_info, char *in_buff, int buff_len);
int dns_package(dns_info_t *dns_info, char *out_buff, int buff_size);
int dns_cheat_response(dns_info_t *dns_info, cheat_pkt_opt_t *cheat_opt, int cheat_opt_num, char *out_buff, int buff_size);

#ifdef __cplusplus
}
#endif
#endif