169 lines
4.4 KiB
C
169 lines
4.4 KiB
C
#ifndef _DNS_HEAD_H
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#define _DNS_HEAD_H
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#include <arpa/inet.h>
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#include <linux/filter.h>
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#include <netdb.h>
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#include <stdint.h>
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#define DNS_RR_A_LEN 4
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#define DNS_RR_AAAA_LEN 16
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#define DNS_MAX_CNAME_LEN 256
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#define DNS_IN_PACKSIZE (512 * 2)
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#define DNS_PACKSIZE (512 * 4)
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typedef enum dns_qr {
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DNS_QR_QUERY = 0,
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DNS_QR_ANSWER = 1,
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} dns_qr;
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typedef enum dns_rr_type {
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DNS_RRS_QD = 0,
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DNS_RRS_AN = 1,
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DNS_RRS_NS = 2,
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DNS_RRS_NR = 3,
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DNS_RRS_END = 4,
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} dns_rr_type;
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typedef enum dns_class { DNS_C_IN = 1, DNS_C_ANY = 255 } dns_class_t;
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typedef enum dns_type {
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DNS_T_A = 1,
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DNS_T_NS = 2,
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DNS_T_CNAME = 5,
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DNS_T_SOA = 6,
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DNS_T_PTR = 12,
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DNS_T_MX = 15,
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DNS_T_TXT = 16,
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DNS_T_AAAA = 28,
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DNS_T_SRV = 33,
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DNS_T_OPT = 41,
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DNS_T_SSHFP = 44,
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DNS_T_SPF = 99,
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DNS_T_AXFR = 252,
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DNS_T_ALL = 255
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} dns_type_t;
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typedef enum dns_opcode {
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DNS_OP_QUERY = 0,
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DNS_OP_IQUERY = 1,
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DNS_OP_STATUS = 2,
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DNS_OP_NOTIFY = 4,
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DNS_OP_UPDATE = 5,
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} dns_opcode_t; /* dns_opcode */
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typedef enum dns_rtcode {
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DNS_RC_NOERROR = 0,
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DNS_RC_FORMERR = 1,
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DNS_RC_SERVFAIL = 2,
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DNS_RC_NXDOMAIN = 3,
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DNS_RC_NOTIMP = 4,
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DNS_RC_REFUSED = 5,
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DNS_RC_YXDOMAIN = 6,
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DNS_RC_YXRRSET = 7,
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DNS_RC_NXRRSET = 8,
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DNS_RC_NOTAUTH = 9,
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DNS_RC_NOTZONE = 10,
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/* EDNS(0) extended RCODEs */
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DNS_RC_BADVERS = 16,
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} dns_rtcode_t; /* dns_rcode */
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struct dns_head {
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unsigned short id; // identification number
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unsigned short qr; /* Query/Response Flag */
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unsigned short opcode; /* Operation Code */
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unsigned char aa; /* Authoritative Answer Flag */
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unsigned char tc; /* Truncation Flag */
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unsigned char rd; /* Recursion Desired */
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unsigned char ra; /* Recursion Available */
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unsigned short rcode; /* Response Code */
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unsigned short qdcount; // number of question entries
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unsigned short ancount; // number of answer entries
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unsigned short nscount; // number of authority entries
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unsigned short nrcount; // number of addititional resource entries
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} __attribute__((packed));
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struct dns_rrs {
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unsigned short next;
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unsigned short len;
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dns_type_t type;
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unsigned char data[0];
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};
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struct dns_packet {
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struct dns_head head;
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unsigned short questions;
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unsigned short answers;
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unsigned short nameservers;
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unsigned short additional;
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int size;
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int len;
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unsigned char data[0];
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};
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struct dns_data_context {
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unsigned char *data;
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unsigned char *ptr;
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unsigned int maxsize;
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};
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struct dns_context {
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struct dns_packet *packet;
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unsigned char *data;
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unsigned int maxsize;
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unsigned char *ptr;
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};
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struct dns_soa {
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char mname[DNS_MAX_CNAME_LEN];
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char rname[DNS_MAX_CNAME_LEN];
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unsigned int serial;
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unsigned int refresh;
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unsigned int retry;
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unsigned int expire;
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unsigned int minimum;
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} __attribute__((packed));;
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struct dns_rrs *dns_get_rrs_next(struct dns_packet *packet, struct dns_rrs *rrs);
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struct dns_rrs *dns_get_rrs_start(struct dns_packet *packet, dns_rr_type type, int *count);
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/*
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* Question
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*/
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int dns_add_domain(struct dns_packet *packet, char *domain, int qtype, int qclass);
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int dns_get_domain(struct dns_rrs *rrs, char *domain, int maxsize, int *qtype, int *qclass);
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/*
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* Answers
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*/
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int dns_add_CNAME(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, char *cname);
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int dns_get_CNAME(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, char *cname, int cname_size);
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int dns_add_A(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, unsigned char addr[DNS_RR_A_LEN]);
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int dns_get_A(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, unsigned char addr[DNS_RR_A_LEN]);
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int dns_add_PTR(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, char *cname);
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int dns_get_PTR(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, char *cname, int cname_size);
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int dns_add_AAAA(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, unsigned char addr[DNS_RR_AAAA_LEN]);
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int dns_get_AAAA(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, unsigned char addr[DNS_RR_AAAA_LEN]);
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int dns_add_SOA(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, struct dns_soa *soa);
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int dns_get_SOA(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, struct dns_soa *soa);
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/*
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* Packet operation
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*/
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int dns_decode(struct dns_packet *packet, int maxsize, unsigned char *data, int size);
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int dns_encode(unsigned char *data, int size, struct dns_packet *packet);
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int dns_packet_init(struct dns_packet *packet, int size, struct dns_head *head);
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#endif |