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/* $OpenBSD: asr_private.h,v 1.2 2012/04/14 12:06:13 eric Exp $ */
/*
* Copyright (c) 2012 Eric Faurot <eric@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <stdio.h>
#define DEBUG
#define QR_MASK (0x1 << 15)
#define OPCODE_MASK (0xf << 11)
#define AA_MASK (0x1 << 10)
#define TC_MASK (0x1 << 9)
#define RD_MASK (0x1 << 8)
#define RA_MASK (0x1 << 7)
#define Z_MASK (0x7 << 4)
#define RCODE_MASK (0xf)
#define OPCODE(v) ((v) & OPCODE_MASK)
#define RCODE(v) ((v) & RCODE_MASK)
struct packed {
char *data;
size_t len;
size_t offset;
const char *err;
};
struct header {
uint16_t id;
uint16_t flags;
uint16_t qdcount;
uint16_t ancount;
uint16_t nscount;
uint16_t arcount;
};
struct query {
char q_dname[MAXDNAME];
uint16_t q_type;
uint16_t q_class;
};
struct rr {
char rr_dname[MAXDNAME];
uint16_t rr_type;
uint16_t rr_class;
uint32_t rr_ttl;
union {
struct {
char cname[MAXDNAME];
} cname;
struct {
uint16_t preference;
char exchange[MAXDNAME];
} mx;
struct {
char nsname[MAXDNAME];
} ns;
struct {
char ptrname[MAXDNAME];
} ptr;
struct {
char mname[MAXDNAME];
char rname[MAXDNAME];
uint32_t serial;
uint32_t refresh;
uint32_t retry;
uint32_t expire;
uint32_t minimum;
} soa;
struct {
struct in_addr addr;
} in_a;
struct {
struct in6_addr addr6;
} in_aaaa;
struct {
uint16_t rdlen;
const void *rdata;
} other;
} rr;
};
#define ASR_MAXNS 5
#define ASR_MAXDB 3
#define ASR_MAXDOM 10
enum async_type {
ASR_SEND,
ASR_SEARCH,
ASR_GETRRSETBYNAME,
ASR_GETHOSTBYNAME,
ASR_GETHOSTBYADDR,
ASR_GETNETBYNAME,
ASR_GETNETBYADDR,
ASR_GETADDRINFO,
ASR_GETNAMEINFO,
ASR_HOSTADDR,
};
enum asr_db_type {
ASR_DB_FILE,
ASR_DB_DNS,
ASR_DB_YP,
};
struct asr_ctx {
int ac_refcount;
int ac_options;
int ac_ndots;
char *ac_domain;
int ac_domcount;
char *ac_dom[ASR_MAXDOM];
int ac_dbcount;
int ac_db[ASR_MAXDB];
int ac_family[3];
char *ac_hostfile;
int ac_nscount;
int ac_nstimeout;
int ac_nsretries;
struct sockaddr *ac_ns[ASR_MAXNS];
};
struct asr {
char *a_path;
time_t a_mtime;
time_t a_rtime;
struct asr_ctx *a_ctx;
};
#define ASYNC_DOM_FQDN 0x00000001
#define ASYNC_DOM_NDOTS 0x00000002
#define ASYNC_DOM_HOSTALIAS 0x00000004
#define ASYNC_DOM_DOMAIN 0x00000008
#define ASYNC_DOM_ASIS 0x00000010
#define ASYNC_NODATA 0x00000100
#define ASYNC_AGAIN 0x00000200
#define ASYNC_EXTIBUF 0x00001000
#define ASYNC_EXTOBUF 0x00002000
struct async {
int (*as_run)(struct async *, struct async_res *);
struct asr_ctx *as_ctx;
int as_type;
int as_state;
/* cond */
int as_timeout;
int as_fd;
/* loop indices in ctx */
int as_dom_step;
int as_dom_idx;
int as_dom_flags;
int as_family_idx;
int as_db_idx;
int as_ns_idx;
int as_ns_cycles;
int as_count;
union {
struct {
int flags;
uint16_t reqid;
int class;
int type;
char *dname; /* not fqdn! */
int rcode; /* response code */
int ancount; /* answer count */
/* io buffers for query/response */
unsigned char *obuf;
size_t obuflen;
size_t obufsize;
unsigned char *ibuf;
size_t ibuflen;
size_t ibufsize;
size_t bufpos;
size_t datalen; /* for tcp io */
} dns;
struct {
int flags;
int class;
int type;
char *name;
struct async *subq;
int saved_h_errno;
unsigned char *ibuf;
size_t ibuflen;
size_t ibufsize;
} search;
struct {
int flags;
int class;
int type;
char *name;
struct async *subq;
} rrset;
struct {
char *name;
int family;
char *dname;
struct async *subq;
char addr[16];
int addrlen;
} hostnamadr;
struct {
char *name;
int family;
struct async *subq;
in_addr_t addr;
} netnamadr;
struct {
char *hostname;
char *servname;
int port_tcp;
int port_udp;
union {
struct sockaddr sa;
struct sockaddr_in sain;
struct sockaddr_in6 sain6;
} sa;
struct addrinfo hints;
struct addrinfo *aifirst;
struct addrinfo *ailast;
struct async *subq;
int flags;
} ai;
struct {
char *hostname;
char *servname;
size_t hostnamelen;
size_t servnamelen;
union {
struct sockaddr sa;
struct sockaddr_in sain;
struct sockaddr_in6 sain6;
} sa;
int flags;
struct async *subq;
} ni;
struct {
char *name;
int family;
int aiflags;
union {
struct sockaddr sa;
struct sockaddr_in sain;
struct sockaddr_in6 sain6;
} sa;
struct async *subq;
int class;
int type;
int ancount;
unsigned char *pkt;
size_t pktlen;
size_t pktpos;
FILE *file;
#define MAXTOKEN 10
char *tokens[MAXTOKEN];
int token_count;
int token_idx;
} host;
} as;
};
#define AS_DB(p) ((p)->as_ctx->ac_db[(p)->as_db_idx - 1])
#define AS_FAMILY(p) ((p)->as_ctx->ac_family[(p)->as_family_idx])
enum asr_state {
ASR_STATE_INIT,
ASR_STATE_SEARCH_DOMAIN,
ASR_STATE_LOOKUP_DOMAIN,
ASR_STATE_NEXT_DOMAIN,
ASR_STATE_NEXT_DB,
ASR_STATE_SAME_DB,
ASR_STATE_NEXT_FAMILY,
ASR_STATE_LOOKUP_FAMILY,
ASR_STATE_NEXT_NS,
ASR_STATE_READ_RR,
ASR_STATE_READ_FILE,
ASR_STATE_UDP_SEND,
ASR_STATE_UDP_RECV,
ASR_STATE_TCP_WRITE,
ASR_STATE_TCP_READ,
ASR_STATE_PACKET,
ASR_STATE_SUBQUERY,
ASR_STATE_NOT_FOUND,
ASR_STATE_HALT,
};
/* asr_utils.c */
void packed_init(struct packed*, char*, size_t);
int pack_header(struct packed*, const struct header*);
int pack_query(struct packed*, uint16_t, uint16_t, const char*);
int unpack_header(struct packed*, struct header*);
int unpack_query(struct packed*, struct query*);
int unpack_rr(struct packed*, struct rr*);
int sockaddr_from_str(struct sockaddr *, int, const char *);
ssize_t dname_from_fqdn(const char*, char*, size_t);
/* asr.c */
struct asr_ctx *asr_use_resolver(struct asr *);
void asr_ctx_unref(struct asr_ctx *);
struct async *async_new(struct asr_ctx *, int);
void async_free(struct async *);
size_t asr_make_fqdn(const char *, const char *, char *, size_t);
size_t asr_domcat(const char *, const char *, char *, size_t);
char *asr_strdname(const char *, char *, size_t);
int asr_iter_db(struct async *);
int asr_iter_ns(struct async *);
int asr_iter_domain(struct async *, const char *, char *, size_t);
int asr_parse_namedb_line(FILE *, char **, int);
/* <*>_async.h */
struct async *res_query_async_ctx(const char *, int, int, unsigned char *, int,
struct asr_ctx *);
struct async *res_search_async_ctx(const char *, int, int, unsigned char *, int,
struct asr_ctx *);
struct async *gethostbyaddr_async_ctx(const void *, socklen_t, int,
struct asr_ctx *);
struct async *hostaddr_async_ctx(const char *, int, int, struct asr_ctx *);
#ifdef DEBUG
extern int asr_debug;
/* asr_debug.h */
const char *asr_querystr(int);
const char *asr_transitionstr(int);
void asr_dump(struct asr *);
void asr_dump_async(struct async *);
void asr_dump_packet(FILE *, const void *, size_t, int);
void asr_printf(const char *fmt, ...);
void async_set_state(struct async *, int);
#else /* DEBUG */
#define async_set_state(a, s) do { (a)->as_state = (s); } while (0)
#endif /* DEBUG */
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