230 lines
6.6 KiB
C
230 lines
6.6 KiB
C
/*************************************************************************
|
|
*
|
|
* Copyright (C) 2018-2020 Ruilin Peng (Nick) <pymumu@gmail.com>.
|
|
*
|
|
* smartdns is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* smartdns is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#ifndef _DNS_HEAD_H
|
|
#define _DNS_HEAD_H
|
|
|
|
#define DNS_RR_A_LEN 4
|
|
#define DNS_RR_AAAA_LEN 16
|
|
#define DNS_MAX_CNAME_LEN 256
|
|
#define DNS_MAX_OPT_LEN 256
|
|
#define DNS_IN_PACKSIZE (512 * 4)
|
|
#define DNS_PACKSIZE (512 * 10)
|
|
#define DNS_DEFAULT_PACKET_SIZE 512
|
|
|
|
#define DNS_ADDR_FAMILY_IP 1
|
|
#define DNS_ADDR_FAMILY_IPV6 2
|
|
|
|
typedef enum dns_qr {
|
|
DNS_QR_QUERY = 0,
|
|
DNS_QR_ANSWER = 1,
|
|
} dns_qr;
|
|
|
|
typedef enum dns_rr_type {
|
|
DNS_RRS_QD = 0,
|
|
DNS_RRS_AN = 1,
|
|
DNS_RRS_NS = 2,
|
|
DNS_RRS_NR = 3,
|
|
DNS_RRS_OPT = 4,
|
|
DNS_RRS_END,
|
|
} dns_rr_type;
|
|
|
|
typedef enum dns_class {
|
|
DNS_C_IN = 1, // DNS C IN
|
|
DNS_C_ANY = 255
|
|
} dns_class_t;
|
|
|
|
typedef enum dns_type {
|
|
DNS_T_A = 1,
|
|
DNS_T_NS = 2,
|
|
DNS_T_CNAME = 5,
|
|
DNS_T_SOA = 6,
|
|
DNS_T_PTR = 12,
|
|
DNS_T_MX = 15,
|
|
DNS_T_TXT = 16,
|
|
DNS_T_AAAA = 28,
|
|
DNS_T_SRV = 33,
|
|
DNS_T_OPT = 41,
|
|
DNS_T_SSHFP = 44,
|
|
DNS_T_SPF = 99,
|
|
DNS_T_AXFR = 252,
|
|
DNS_T_ALL = 255
|
|
} dns_type_t;
|
|
|
|
typedef enum dns_opt_code {
|
|
DNS_OPT_T_ECS = 8, // OPT ECS
|
|
DNS_OPT_T_TCP_KEEPALIVE = 11,
|
|
DNS_OPT_T_ALL = 255
|
|
} dns_opt_code_t;
|
|
|
|
typedef enum dns_opcode {
|
|
DNS_OP_QUERY = 0,
|
|
DNS_OP_IQUERY = 1,
|
|
DNS_OP_STATUS = 2,
|
|
DNS_OP_NOTIFY = 4,
|
|
DNS_OP_UPDATE = 5,
|
|
} dns_opcode_t; /* dns_opcode */
|
|
|
|
typedef enum dns_rtcode {
|
|
DNS_RC_NOERROR = 0,
|
|
DNS_RC_FORMERR = 1,
|
|
DNS_RC_SERVFAIL = 2,
|
|
DNS_RC_NXDOMAIN = 3,
|
|
DNS_RC_NOTIMP = 4,
|
|
DNS_RC_REFUSED = 5,
|
|
DNS_RC_YXDOMAIN = 6,
|
|
DNS_RC_YXRRSET = 7,
|
|
DNS_RC_NXRRSET = 8,
|
|
DNS_RC_NOTAUTH = 9,
|
|
DNS_RC_NOTZONE = 10,
|
|
/* EDNS(0) extended RCODEs */
|
|
DNS_RC_BADVERS = 16,
|
|
} dns_rtcode_t; /* dns_rcode */
|
|
|
|
/* dns packet head */
|
|
struct dns_head {
|
|
unsigned short id; /* identification number */
|
|
unsigned short qr; /* Query/Response Flag */
|
|
unsigned short opcode; /* Operation Code */
|
|
unsigned char aa; /* Authoritative Answer Flag */
|
|
unsigned char tc; /* Truncation Flag */
|
|
unsigned char rd; /* Recursion Desired */
|
|
unsigned char ra; /* Recursion Available */
|
|
unsigned short rcode; /* Response Code */
|
|
unsigned short qdcount; /* number of question entries */
|
|
unsigned short ancount; /* number of answer entries */
|
|
unsigned short nscount; /* number of authority entries */
|
|
unsigned short nrcount; /* number of addititional resource entries */
|
|
} __attribute__((packed));
|
|
|
|
struct dns_rrs {
|
|
unsigned short next;
|
|
unsigned short len;
|
|
dns_type_t type;
|
|
unsigned char data[0];
|
|
};
|
|
|
|
/* packet haed */
|
|
struct dns_packet {
|
|
struct dns_head head;
|
|
unsigned short questions;
|
|
unsigned short answers;
|
|
unsigned short nameservers;
|
|
unsigned short additional;
|
|
unsigned short optcount;
|
|
unsigned short optional;
|
|
unsigned short payloadsize;
|
|
int size;
|
|
int len;
|
|
unsigned char data[0];
|
|
};
|
|
|
|
/* RRS encode/decode context */
|
|
struct dns_data_context {
|
|
unsigned char *data;
|
|
unsigned char *ptr;
|
|
unsigned int maxsize;
|
|
};
|
|
|
|
/* packet encode/decode context */
|
|
struct dns_context {
|
|
struct dns_packet *packet;
|
|
unsigned char *data;
|
|
unsigned int maxsize;
|
|
unsigned char *ptr;
|
|
};
|
|
|
|
/* SOA data */
|
|
struct dns_soa {
|
|
char mname[DNS_MAX_CNAME_LEN];
|
|
char rname[DNS_MAX_CNAME_LEN];
|
|
unsigned int serial;
|
|
unsigned int refresh;
|
|
unsigned int retry;
|
|
unsigned int expire;
|
|
unsigned int minimum;
|
|
} __attribute__((packed));
|
|
|
|
#define DNS_OPT_ECS_FAMILY_IPV4 1
|
|
#define DNS_OPT_ECS_FAMILY_IPV6 2
|
|
|
|
/* OPT ECS */
|
|
struct dns_opt_ecs {
|
|
unsigned short family;
|
|
unsigned char source_prefix;
|
|
unsigned char scope_prefix;
|
|
unsigned char addr[DNS_RR_AAAA_LEN];
|
|
};
|
|
|
|
/* OPT */
|
|
struct dns_opt {
|
|
unsigned short code;
|
|
unsigned short length;
|
|
unsigned char data[0];
|
|
} __attribute__((packed));
|
|
|
|
struct dns_rrs *dns_get_rrs_next(struct dns_packet *packet, struct dns_rrs *rrs);
|
|
struct dns_rrs *dns_get_rrs_start(struct dns_packet *packet, dns_rr_type type, int *count);
|
|
|
|
/*
|
|
* Question
|
|
*/
|
|
int dns_add_domain(struct dns_packet *packet, char *domain, int qtype, int qclass);
|
|
int dns_get_domain(struct dns_rrs *rrs, char *domain, int maxsize, int *qtype, int *qclass);
|
|
|
|
/*
|
|
* Answers
|
|
*/
|
|
int dns_add_CNAME(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, char *cname);
|
|
int dns_get_CNAME(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, char *cname, int cname_size);
|
|
|
|
int dns_add_A(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, unsigned char addr[DNS_RR_A_LEN]);
|
|
int dns_get_A(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, unsigned char addr[DNS_RR_A_LEN]);
|
|
|
|
int dns_add_PTR(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, char *cname);
|
|
int dns_get_PTR(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, char *cname, int cname_size);
|
|
|
|
int dns_add_AAAA(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl,
|
|
unsigned char addr[DNS_RR_AAAA_LEN]);
|
|
int dns_get_AAAA(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, unsigned char addr[DNS_RR_AAAA_LEN]);
|
|
|
|
int dns_add_SOA(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, struct dns_soa *soa);
|
|
int dns_get_SOA(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, struct dns_soa *soa);
|
|
|
|
int dns_add_NS(struct dns_packet *packet, dns_rr_type type, char *domain, int ttl, char *cname);
|
|
int dns_get_NS(struct dns_rrs *rrs, char *domain, int maxsize, int *ttl, char *cname, int cname_size);
|
|
|
|
int dns_set_OPT_payload_size(struct dns_packet *packet, int payload_size);
|
|
int dns_get_OPT_payload_size(struct dns_packet *packet);
|
|
|
|
int dns_add_OPT_ECS(struct dns_packet *packet, struct dns_opt_ecs *ecs);
|
|
int dns_get_OPT_ECS(struct dns_rrs *rrs, unsigned short *opt_code, unsigned short *opt_len, struct dns_opt_ecs *ecs);
|
|
|
|
int dns_add_OPT_TCP_KEEYALIVE(struct dns_packet *packet, unsigned short timeout);
|
|
int dns_get_OPT_TCP_KEEYALIVE(struct dns_rrs *rrs, unsigned short *opt_code, unsigned short *opt_len,
|
|
unsigned short *timeout);
|
|
/*
|
|
* Packet operation
|
|
*/
|
|
int dns_decode(struct dns_packet *packet, int maxsize, unsigned char *data, int size);
|
|
int dns_encode(unsigned char *data, int size, struct dns_packet *packet);
|
|
|
|
int dns_packet_init(struct dns_packet *packet, int size, struct dns_head *head);
|
|
|
|
#endif
|