DNS defines

Generic DNS values. More...

Detailed Description

Generic DNS values.

Modules
	DNS cache
	DNS cache.
	DNS message parser and composer
	Parsing and composition of DNS messages.

Files
file	dns.h
	Generic DNS values.

Functions
static int	dns_query (const char *domain_name, void *addr_out, int family)
	Get IP address for DNS name. More...

DNS defines
#define	DNS_TYPE_A   (1)
#define	DNS_TYPE_AAAA   (28)
#define	DNS_CLASS_IN   (1)

Field lengths
#define	RR_TYPE_LENGTH   (2U)
#define	RR_CLASS_LENGTH   (2U)
#define	RR_TTL_LENGTH   (4U)
#define	RR_RDLENGTH_LENGTH   (2U)

Function Documentation

dns_query()

static int dns_query ( const char *  domain_name, void *  addr_out, int  family  )

inlinestatic

Get IP address for DNS name.

This function will synchronously try to resolve a DNS A or AAAA record by contacting the DNS server specified in the global variable sock_dns_server.

By supplying AF_INET, AF_INET6 or AF_UNSPEC in family requesting of A records (IPv4), AAAA records (IPv6) or both can be selected.

This function will return the first DNS record it receives. IF both A and AAAA are requested, AAAA will be preferred.

Note

addr_out needs to provide space for any possible result! (4byte when family==AF_INET, 16byte otherwise)

Parameters

[in]	domain_name	DNS name to resolve into address
[out]	addr_out	buffer to write result into
[in]	family	Either AF_INET, AF_INET6 or AF_UNSPEC

Returns

the size of the resolved address on success

< 0 otherwise

Definition at line 73 of file dns.h.