This commit is contained in:
Nick Peng
2018-05-12 10:09:42 +08:00
parent b8cb84fc4a
commit 675534ab12
2 changed files with 32 additions and 11 deletions

30
dns.c
View File

@@ -102,7 +102,7 @@ unsigned char *dns_rr_add_start(struct dns_packet *packet, int *maxlen)
return rrs->data;
}
int dns_rr_add_end(struct dns_packet *packet, int type, int len)
int dns_rr_add_end(struct dns_packet *packet, int type, dns_type_t rrtype, int len)
{
struct dns_rrs *rrs;
struct dns_head *head = &packet->head;
@@ -140,7 +140,8 @@ int dns_rr_add_end(struct dns_packet *packet, int type, int len)
*count += 1;
rrs->next = *start;
rrs->len = len;
*start = packet->len;
rrs->type = rrtype;
*start = packet->len;
packet->len += len;
return 0;
}
@@ -257,13 +258,17 @@ int dns_decode_qd(unsigned char *data, int size, char *domain, int domain_size,
return len;
}
/*
* Format:
* |DNS_NAME\0(string)|qtype(short)|qclass(short)|
*/
int dns_add_domain(struct dns_packet *packet, char *domain, int qtype, int qclass)
{
int maxlen = 0;
int i;
int len = 0;
unsigned char *data = dns_rr_add_start(packet, &maxlen);
unsigned char *data_ptr = data;
if (data == NULL) {
return -1;
}
@@ -287,13 +292,12 @@ int dns_add_domain(struct dns_packet *packet, char *domain, int qtype, int qclas
data += 2;
len += 2;
return dns_rr_add_end(packet, DNS_RR_QD, len);
return dns_rr_add_end(packet, DNS_RR_QD, DNS_T_CNAME, len);
}
int dns_add_A(struct dns_packet *packet, char *domain, int qtype, int qclass)
int dns_add_A(struct dns_packet *packet, unsigned char addr[4])
{
int maxlen = 0;
int i;
int len = 0;
unsigned char *data = dns_rr_add_start(packet, &maxlen);
unsigned char *data_ptr = data;
@@ -301,23 +305,27 @@ int dns_add_A(struct dns_packet *packet, char *domain, int qtype, int qclass)
return -1;
}
memcpy(data, addr, 4);
data += 4;
len += 4;
return dns_rr_add_end(packet, DNS_RR_AN, len);
return dns_rr_add_end(packet, DNS_RR_AN, DNS_T_A, len);
}
int dns_add_AAAA(struct dns_packet *packet, char *domain, int qtype, int qclass)
int dns_add_AAAA(struct dns_packet *packet, unsigned char addr[16])
{
int maxlen = 0;
int i;
int len = 0;
unsigned char *data = dns_rr_add_start(packet, &maxlen);
unsigned char *data_ptr = data;
if (data == NULL) {
return -1;
}
memcpy(data, addr, 4);
data += 4;
len += 4;
return dns_rr_add_end(packet, DNS_RR_AN, len);
return dns_rr_add_end(packet, DNS_RR_AN, DNS_T_AAAA, len);
}
int dns_get_domain(struct dns_rrs *rrs, char *domain, int maxsize, int *qtype, int *qclass)

13
dns.h
View File

@@ -148,6 +148,7 @@ typedef union dns_answer_t {
struct dns_rrs {
unsigned short next;
unsigned short len;
dns_type_t type;
unsigned char data[0];
};
@@ -164,4 +165,16 @@ struct dns_packet {
int dns_decode(struct dns_packet *packet, 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);
int dns_get_domain(struct dns_rrs *rrs, char *domain, int maxsize, int *qtype, int *qclass);
int dns_add_domain(struct dns_packet *packet, char *domain, int qtype, int qclass);
struct dns_rrs *dns_rr_get_next(struct dns_packet *packet, struct dns_rrs *rrs);
struct dns_rrs *dns_rr_get_start(struct dns_packet *packet, int type, int *count);
#endif