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#ifndef _ARPA_NAMESER_H_
#include <resolv/arpa/nameser.h>
# ifndef _ISOMAC
/* If the machine allows unaligned access we can do better than using
the NS_GET16, NS_GET32, NS_PUT16, and NS_PUT32 macros from the
installed header. */
#include <string.h>
#include <stdint.h>
#include <netinet/in.h>
extern const struct _ns_flagdata _ns_flagdata[] attribute_hidden;
extern unsigned int __ns_get16 (const unsigned char *) __THROW;
extern unsigned long __ns_get32 (const unsigned char *) __THROW;
int __ns_name_ntop (const unsigned char *, char *, size_t) __THROW;
int __ns_name_unpack (const unsigned char *, const unsigned char *,
const unsigned char *, unsigned char *, size_t) __THROW;
/* Like ns_samename, but for uncompressed binary names. Return true
if the two arguments compare are equal as case-insensitive domain
names. */
_Bool __ns_samebinaryname (const unsigned char *, const unsigned char *)
attribute_hidden;
#define ns_msg_getflag(handle, flag) \
(((handle)._flags & _ns_flagdata[flag].mask) >> _ns_flagdata[flag].shift)
libresolv_hidden_proto (ns_get16)
libresolv_hidden_proto (ns_get32)
libresolv_hidden_proto (ns_put16)
libresolv_hidden_proto (ns_put32)
libresolv_hidden_proto (ns_initparse)
libresolv_hidden_proto (ns_skiprr)
libresolv_hidden_proto (ns_parserr)
libresolv_hidden_proto (ns_sprintrr)
libresolv_hidden_proto (ns_sprintrrf)
libresolv_hidden_proto (ns_samedomain)
libresolv_hidden_proto (ns_format_ttl)
extern __typeof (ns_makecanon) __libc_ns_makecanon;
libc_hidden_proto (__libc_ns_makecanon)
extern __typeof (ns_name_compress) __ns_name_compress;
libc_hidden_proto (__ns_name_compress)
extern __typeof (ns_name_ntop) __ns_name_ntop;
libc_hidden_proto (__ns_name_ntop)
extern __typeof (ns_name_pack) __ns_name_pack;
libc_hidden_proto (__ns_name_pack)
extern __typeof (ns_name_pton) __ns_name_pton;
libc_hidden_proto (__ns_name_pton)
extern __typeof (ns_name_skip) __ns_name_skip;
libc_hidden_proto (__ns_name_skip)
extern __typeof (ns_name_uncompress) __ns_name_uncompress;
libc_hidden_proto (__ns_name_uncompress)
extern __typeof (ns_name_unpack) __ns_name_unpack;
libc_hidden_proto (__ns_name_unpack)
extern __typeof (ns_samename) __libc_ns_samename;
libc_hidden_proto (__libc_ns_samename)
/* Packet parser helper functions. */
/* Verify that P points to an uncompressed domain name in wire format.
On success, return the length of the encoded name, including the
terminating null byte. On failure, return -1 and set errno. EOM
must point one past the last byte in the packet. */
int __ns_name_length_uncompressed (const unsigned char *p,
const unsigned char *eom) attribute_hidden;
/* Iterator over the resource records in a DNS packet. */
struct ns_rr_cursor
{
/* These members are not changed after initialization. */
const unsigned char *begin; /* First byte of packet. */
const unsigned char *end; /* One past the last byte of the packet. */
const unsigned char *first_rr; /* First resource record (or packet end). */
/* Advanced towards the end while reading the packet. */
const unsigned char *current;
};
/* Returns the RCODE field from the DNS header. */
static inline int
ns_rr_cursor_rcode (const struct ns_rr_cursor *c)
{
return c->begin[3] & 0x0f; /* Lower 4 bits at offset 3. */
}
/* Returns the length of the answer section according to the DNS header. */
static inline int
ns_rr_cursor_ancount (const struct ns_rr_cursor *c)
{
return c->begin[6] * 256 + c->begin[7]; /* 16 bits at offset 6. */
}
/* Returns the length of the authority (name server) section according
to the DNS header. */
static inline int
ns_rr_cursor_nscount (const struct ns_rr_cursor *c)
{
return c->begin[8] * 256 + c->begin[9]; /* 16 bits at offset 8. */
}
/* Returns the length of the additional data section according to the
DNS header. */
static inline int
ns_rr_cursor_adcount (const struct ns_rr_cursor *c)
{
return c->begin[10] * 256 + c->begin[11]; /* 16 bits at offset 10. */
}
/* Returns a pointer to the uncompressed question name in wire
format. */
static inline const unsigned char *
ns_rr_cursor_qname (const struct ns_rr_cursor *c)
{
return c->begin + 12; /* QNAME starts right after the header. */
}
/* Returns the question type of the first and only question. */
static inline const int
ns_rr_cursor_qtype (const struct ns_rr_cursor *c)
{
/* 16 bits 4 bytes back from the first RR header start. */
return c->first_rr[-4] * 256 + c->first_rr[-3];
}
/* Returns the clss of the first and only question (usually C_IN). */
static inline const int
ns_rr_cursor_qclass (const struct ns_rr_cursor *c)
{
/* 16 bits 2 bytes back from the first RR header start. */
return c->first_rr[-2] * 256 + c->first_rr[-1];
}
/* Initializes *C to cover the packet [BUF, BUF+LEN). Returns false
if LEN is less than sizeof (*HD), if the packet does not contain a
full (uncompressed) question, or if the question count is not 1. */
_Bool __ns_rr_cursor_init (struct ns_rr_cursor *c,
const unsigned char *buf, size_t len)
attribute_hidden;
/* Like ns_rr, but the record owner name is not decoded into text format. */
struct ns_rr_wire
{
unsigned char rname[NS_MAXCDNAME]; /* Owner name of the record. */
uint16_t rtype; /* Resource record type (T_*). */
uint16_t rclass; /* Resource record class (C_*). */
uint32_t ttl; /* Time-to-live field. */
const unsigned char *rdata; /* Start of resource record data. */
uint16_t rdlength; /* Length of the data at rdata, in bytes. */
};
/* Attempts to parse the record at C into *RR. On success, return
true, and C is advanced past the record, and RR->rdata points to
the record data. On failure, errno is set to EMSGSIZE, and false
is returned. */
_Bool __ns_rr_cursor_next (struct ns_rr_cursor *c, struct ns_rr_wire *rr)
attribute_hidden;
# endif /* !_ISOMAC */
#endif
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