[adns] / src / internal.h

/**/

#ifndef ADNS_INTERNAL_H_INCLUDED
#define ADNS_INTERNAL_H_INCLUDED

#define PRINTFFORMAT(a,b) __attribute__((format(printf,a,b)))
typedef unsigned char byte;

#include <stdarg.h>
#include <assert.h>
#include <unistd.h>

#include <sys/time.h>

#include "adns.h"

/* Configuration and constants */

#define MAXSERVERS 5
#define UDPMAXRETRIES /*15*/5
#define UDPRETRYMS 2000
#define TCPMS 30000
#define LOCALRESOURCEMS 20

#define DNS_PORT 53
#define DNS_MAXUDP 512
#define DNS_MAXDOMAIN 255
#define DNS_HDRSIZE 12
#define DNS_CLASS_IN 1

typedef enum {
  rcode_noerror,
  rcode_formaterror,
  rcode_servfail,
  rcode_nxdomain,
  rcode_notimp,
  rcode_refused
} dns_rcode;

/* Shared data structures */

typedef union {
  adns_status status;
  char *cp;
  adns_rrtype type;
  int i;
  struct in_addr ia;
  unsigned long ul;
} rr_align;

typedef struct {
  int used, avail;
  byte *buf;
} vbuf;

typedef union {
  void *ext;
  int dmaddr_index;
} qcontext;

typedef struct {
  adns_rrtype type;
  const char *name;
  int rrsz;

  adns_status (*parse)(adns_state ads, adns_query qu, int serv,
		       const byte *dgram, int dglen, int cbyte, int max,
		       void *store_r);
  /* Parse one RR, in dgram of length dglen, starting at cbyte and
   * extending until at most max.
   *
   * The RR should be stored at *store_r, of length qu->typei->rrsz.
   *
   * If there is an overrun which might indicate truncation, it should set
   * *rdstart to -1; otherwise it may set it to anything else positive.
   */

  void (*makefinal)(adns_state ads, adns_query qu, void *data);
  /* Change memory management of *data.
   * Previously, used alloc_interim, now use alloc_final.
   */
} typeinfo;

typedef struct allocnode {
  struct allocnode *next;
} allocnode;

union maxalign {
  byte d[1];
  struct in_addr ia;
  long l;
  void *p;
  void (*fp)(void);
  union maxalign *up;
} data;

struct adns__query {
  enum { query_udp, query_tcpwait, query_tcpsent, query_child, query_done } state;
  adns_query back, next, parent;
  struct { adns_query head, tail; } children;
  struct { adns_query back, next; } siblings;
  struct allocnode *allocations;
  int interim_allocd;
  void *final_allocspace;
  
  const typeinfo *typei;
  char *query_dgram;
  int query_dglen;
  
  vbuf vb;
  /* General-purpose messing-about buffer.
   * Wherever a `big' interface is crossed, this may be corrupted/changed
   * unless otherwise specified.
   */

  adns_answer *answer;
  /* This is allocated when a query is submitted, to avoid being unable
   * to relate errors to queries if we run out of memory.  During
   * query processing status, rrs is 0.  cname is set if
   * we found a cname (this corresponds to cname_dgram in the query
   * structure).  type is set from the word go.  nrrs and rrs
   * are set together, when we find how many rrs there are.
   */
  
  byte *cname_dgram;
  int cname_dglen, cname_begin;
  
  int id, flags, udpretries;
  int udpnextserver;
  unsigned long udpsent, tcpfailed; /* bitmap indexed by server */
  struct timeval timeout;
  qcontext context;

  /* Possible states:
   *
   *  state   Queue   child  id   nextudpserver  sentudp     failedtcp
   *				  
   *  udp     NONE    null   >=0  0              zero        zero
   *  udp     timew   null   >=0  any            nonzero     zero
   *  udp     NONE    null   >=0  any            nonzero     zero
   *				  
   *  tcpwait timew   null   >=0  irrelevant     zero        any
   *  tcpsent timew   null   >=0  irrelevant     zero        any
   *				  
   *  child   childw  set    >=0  irrelevant     irrelevant  irrelevant
   *  done    output  null   -1   irrelevant     irrelevant  irrelevant
   *
   *			      +------------------------+
   *             START -----> |      udp/NONE          |
   *			      +------------------------+
   *                         /                       |\  \
   *        too big for UDP /             UDP timeout  \  \ send via UDP
   *        do this ASAP!  /              more retries  \  \   do this ASAP!
   *                     |_                  desired     \  _|
   *		  +---------------+     	    	+-----------+
   *              | tcpwait/timew | ____                | udp/timew |
   *              +---------------+     \	    	+-----------+
   *                    |  ^             |                 | |
   *     TCP conn'd;    |  | TCP died    |                 | |
   *     send via TCP   |  | more        |     UDP timeout | |
   *     do this ASAP!  |  | servers     |      no more    | |
   *                    v  | to try      |      retries    | |
   *              +---------------+      |      desired    | |
   *              | tcpsent/timew | ____ |                 | |
   *    	  +---------------+     \|                 | |
   *                  \   \ TCP died     | TCP             | |
   *                   \   \ no more     | timeout         / |
   *                    \   \ servers    |                /  |
   *                     \   \ to try    |               /   |
   *                  got \   \          v             |_    / got
   *                 reply \   _| +------------------+      / reply
   *   	       	       	    \  	  | done/output FAIL |     /
   *                         \    +------------------+    /
   *                          \                          /
   *                           _|                      |_
   *                             (..... got reply ....)
   *                              /                   \
   *        need child query/ies /                     \ no child query
   *                            /                       \
   *                          |_                         _|
   *		    +--------------+		       +----------------+
   *                | child/childw | ----------------> | done/output OK |
   *                +--------------+  children done    +----------------+
   */
};

struct adns__state {
  adns_initflags iflags;
  FILE *diagfile;
  struct { adns_query head, tail; } timew, childw, output;
  int nextid, udpsocket, tcpsocket;
  vbuf tcpsend, tcprecv;
  int nservers, tcpserver;
  enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate;
  struct timeval tcptimeout;
  struct server {
    struct in_addr addr;
  } servers[MAXSERVERS];
};

/* From setup.c: */

void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent,
		 int serv, adns_query qu, const char *fmt, va_list al);

void adns__debug(adns_state ads, int serv, adns_query qu,
		 const char *fmt, ...) PRINTFFORMAT(4,5);
void adns__warn(adns_state ads, int serv, adns_query qu,
		const char *fmt, ...) PRINTFFORMAT(4,5);
void adns__diag(adns_state ads, int serv, adns_query qu,
		const char *fmt, ...) PRINTFFORMAT(4,5);

int adns__vbuf_ensure(vbuf *vb, int want);
int adns__vbuf_appendstr(vbuf *vb, const char *data);
int adns__vbuf_append(vbuf *vb, const byte *data, int len);
/* 1=>success, 0=>realloc failed */
void adns__vbuf_appendq(vbuf *vb, const byte *data, int len);
void adns__vbuf_init(vbuf *vb);
void adns__vbuf_free(vbuf *vb);

int adns__setnonblock(adns_state ads, int fd); /* => errno value */

/* From submit.c: */

int adns__internal_submit(adns_state ads, adns_query *query_r,
			  adns_rrtype type, vbuf *qumsg_vb, int id,
			  adns_queryflags flags, struct timeval now,
			  adns_status failstat, const qcontext *ctx);
/* Submits a query (for internal use, called during external submits).
 *
 * The new query is returned in *query_r, or we return adns_s_nomemory.
 *
 * The query datagram should already have been assembled in qumsg_vb;
 * the memory for it is _taken over_ by this routine whether it
 * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
 *
 * If failstat is nonzero then if we are successful in creating the query
 * it is immediately failed with code failstat (but _submit still succeds).
 *
 * ctx is copied byte-for-byte into the query.
 */

void *adns__alloc_interim(adns_query qu, size_t sz);
/* Allocates some memory, and records which query it came from
 * and how much there was.
 *
 * If an error occurs in the query, all its memory is simply freed.
 *
 * If the query succeeds, one large buffer will be made which is
 * big enough for all these allocations, and then adns__alloc_final
 * will get memory from this buffer.
 *
 * _alloc_interim can fail, in which case it will fail the query too,
 * so nothing more need be done with it.
 */

void *adns__alloc_final(adns_query qu, size_t sz);
/* Cannot fail.
 */

void adns__makefinal_block(adns_query qu, void **blpp, size_t sz);
void adns__makefinal_str(adns_query qu, char **strp);

/* From query.c: */

void adns__query_udp(adns_state ads, adns_query qu, struct timeval now);
void adns__query_tcp(adns_state ads, adns_query qu, struct timeval now);
adns_status adns__mkquery(adns_state ads, vbuf *vb,
			  const char *owner, int ol, int *id_r,
			  const typeinfo *typei, adns_queryflags flags);
/* Assembles a query packet in vb, and returns id at *id_r. */

void adns__query_ok(adns_state ads, adns_query qu);
void adns__query_fail(adns_state ads, adns_query qu, adns_status stat);

void adns__reset_cnameonly(adns_state ads, adns_query qu);
/* Resets all of the memory management stuff etc. to
 * take account of only the CNAME.  Used when we find an error somewhere
 * and want to just report the error (with perhaps CNAME info), and also
 * when we're halfway through RRs in a datagram and discover that we
 * need to retry the query.
 */
   
/* From reply.c: */

void adns__procdgram(adns_state ads, const byte *dgram, int len,
		     int serv, struct timeval now);

/* From types.c: */

const typeinfo *adns__findtype(adns_rrtype type);

/* From parse.c: */

typedef struct {
  adns_state ads;
  int serv;
  const byte *dgram;
  int dglen, max, cbyte, namelen;
  int *dmend_rlater, *namelen_rlater;
} findlabel_state;

void adns__findlabel_start(findlabel_state *fls,
			   adns_state ads, int serv,
			   const byte *dgram, int dglen, int max,
			   int dmbegin, int *dmend_rlater);
/* Finds labels in a domain in a datagram.
 *
 * Call this routine first.
 * endpoint_rlater may be null.
 */

adns_status adns__findlabel_next(findlabel_state *fls,
				 int *lablen_r, int *labstart_r);
/* Then, call this one repeatedly.
 *
 * It will return adns_s_ok if all is well, and tell you the length
 * and start of successive labels.  labstart_r may be null, but
 * lablen_r must not be.
 *
 * After the last label, it will return with *lablen_r zero.
 * Do not then call it again; instead, just throw away the findlabel_state.
 *
 * *dmend_rlater will have been set to point to the next part of
 * the datagram after the label (or after the uncompressed part,
 * if compression was used).  *namelen_rlater will have been set
 * to the length of the domain name (total length of labels plus
 * 1 for each intervening dot).
 *
 * If the datagram appears to be truncated, *lablen_r will be -1.
 * *dmend_rlater, *labstart_r and *namelen_r may contain garbage.
 * Do not call _next again.
 *
 * There may also be errors, in which case *dmend_rlater,
 * *namelen_rlater, *lablen_r and *labstart_r may contain garbage.
 * Do not then call findlabel_next again.
 */

adns_status adns__parse_domain(adns_state ads, int serv, vbuf *vb,
			       const byte *dgram, int dglen,
			       int *cbyte_io, int max);
/* vb must already have been initialised; it will be reset if necessary.
 * If there is truncation, vb->used will be set to 0; otherwise
 * (if there is no error) vb will be null-terminated.
 * If there is an error vb and *cbyte_io may be left indeterminate.
 */

adns_status adns__findrr(adns_state ads, int serv,
			 const byte *dgram, int dglen, int *cbyte_io,
			 int *type_r, int *class_r, int *rdlen_r, int *rdstart_r,
			 const byte *eo_dgram, int eo_dglen, int eo_cbyte,
			 int *eo_matched_r);
  /* Finds the extent and some of the contents of an RR in a datagram
   * and does some checks.  The datagram is *dgram, length dglen, and
   * the RR starts at *cbyte_io (which is updated afterwards to point
   * to the end of the RR).
   *
   * The type, class and RRdata length and start are returned iff
   * the corresponding pointer variables are not null.  type_r and
   * class_r may not be null.
   *
   * If the caller thinks they know what the owner of the RR ought to
   * be they can pass in details in eo_*: this is another (or perhaps
   * the same datagram), and a pointer to where the putative owner
   * starts in that datagram.  In this case *eo_matched_r will be set
   * to 1 if the datagram matched or 0 if it did not.  Either
   * both eo_dgram and eo_matched_r must both be non-null, or they
   * must both be null (in which case eo_dglen and eo_cbyte will be ignored).
   * The eo datagram and contained owner domain MUST be valid and
   * untruncated.
   *
   * If there is truncation then *type_r will be set to -1 and
   * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
   * undefined.
   *
   * If an error is returned then *type_r will be undefined too.
   */

int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len);

/* From event.c: */

void adns__tcp_broken(adns_state ads, const char *what, const char *why);
void adns__tcp_tryconnect(adns_state ads, struct timeval now);
void adns__autosys(adns_state ads, struct timeval now);

/* Useful static inline functions: */

static inline void timevaladd(struct timeval *tv_io, long ms) {
  struct timeval tmp;
  assert(ms>=0);
  tmp= *tv_io;
  tmp.tv_usec += (ms%1000)*1000000;
  tmp.tv_sec += ms/1000;
  if (tmp.tv_usec >= 1000000) { tmp.tv_sec++; tmp.tv_usec -= 1000; }
  *tv_io= tmp;
}

static inline int ctype_whitespace(int c) { return c==' ' || c=='\n' || c=='\t'; }
static inline int ctype_digit(int c) { return c>='0' && c<='9'; }
static inline int ctype_alpha(int c) {
  return (c >= 'a' && c <= 'z') || (c >= 'A' || c <= 'Z');
}

/* Useful macros */

#define MEM_ROUND(sz) \
  (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
   * sizeof(union maxalign) )

#define LIST_INIT(list) ((list).head= (list).tail= 0)

#define LIST_UNLINK_PART(list,node,part) \
  do { \
    if ((node)->back) (node)->back->part next= (node)->part next; \
      else                        (list).head= (node)->part next; \
    if ((node)->next) (node)->next->part back= (node)->part back; \
      else                        (list).tail= (node)->part back; \
  } while(0)

#define LIST_LINK_TAIL_PART(list,node,part) \
  do { \
    (node)->part back= 0; \
    (node)->part next= (list).tail; \
    if ((list).tail) (list).tail->part back= (node); else (list).part head= (node); \
    (list).tail= (node); \
  } while(0)

#define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
#define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)

#define GETIL_B(cb) (dgram[(cb)++])
#define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
#define GET_W(cb,tv) ((tv)=0, (tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))

#endif
Commit	Line	Data
37e28fde	1	/**/
	2
	3	#ifndef ADNS_INTERNAL_H_INCLUDED
	4	#define ADNS_INTERNAL_H_INCLUDED
	5
4353a5c4	6	#define PRINTFFORMAT(a,b) __attribute__((format(printf,a,b)))
	7	typedef unsigned char byte;
	8
	9	#include <stdarg.h>
	10	#include <assert.h>
	11	#include <unistd.h>
	12
37e28fde	13	#include <sys/time.h>
	14
	15	#include "adns.h"
	16
	17	/* Configuration and constants */
	18
	19	#define MAXSERVERS 5
b9de380c	20	#define UDPMAXRETRIES /15/5
37e28fde	21	#define UDPRETRYMS 2000
	22	#define TCPMS 30000
	23	#define LOCALRESOURCEMS 20
b9de380c	24
98a3f706	25	#define DNS_PORT 53
b9de380c	26	#define DNS_MAXUDP 512
	27	#define DNS_MAXDOMAIN 255
	28	#define DNS_HDRSIZE 12
	29	#define DNS_CLASS_IN 1
37e28fde	30
98a3f706	31	typedef enum {
	32	rcode_noerror,
	33	rcode_formaterror,
	34	rcode_servfail,
	35	rcode_nxdomain,
	36	rcode_notimp,
	37	rcode_refused
	38	} dns_rcode;
	39
37e28fde	40	/* Shared data structures */
37e28fde	41
4353a5c4	42	typedef union {
37e28fde	43	adns_status status;
	44	char *cp;
	45	adns_rrtype type;
4353a5c4	46	int i;
37e28fde	47	struct in_addr ia;
37e28fde	48	unsigned long ul;
4353a5c4	49	} rr_align;
	50
	51	typedef struct {
	52	int used, avail;
	53	byte *buf;
	54	} vbuf;
	55
	56	typedef union {
	57	void *ext;
	58	int dmaddr_index;
	59	} qcontext;
37e28fde	60
0ba0614a	61	typedef struct {
0ba0614a	62	adns_rrtype type;
68442019	63	const char *name;
98a3f706	64	int rrsz;
8e5b0abb	65
8e5b0abb	66	adns_status (*parse)(adns_state ads, adns_query qu, int serv,
31144a72	67	const byte *dgram, int dglen, int cbyte, int max,
	68	void *store_r);
	69	/* Parse one RR, in dgram of length dglen, starting at cbyte and
	70	* extending until at most max.
	71	*
	72	* The RR should be stored at *store_r, of length qu->typei->rrsz.
	73	*
	74	* If there is an overrun which might indicate truncation, it should set
	75	* *rdstart to -1; otherwise it may set it to anything else positive.
8e5b0abb	76	*/
	77
	78	void (makefinal)(adns_state ads, adns_query qu, void data);
	79	/* Change memory management of *data.
	80	* Previously, used alloc_interim, now use alloc_final.
31144a72	81	*/
0ba0614a	82	} typeinfo;
0ba0614a	83
8e5b0abb	84	typedef struct allocnode {
	85	struct allocnode *next;
	86	} allocnode;
	87
	88	union maxalign {
	89	byte d[1];
	90	struct in_addr ia;
	91	long l;
	92	void *p;
	93	void (*fp)(void);
	94	union maxalign *up;
	95	} data;
	96
37e28fde	97	struct adns__query {
ddfda861	98	enum { query_udp, query_tcpwait, query_tcpsent, query_child, query_done } state;
4353a5c4	99	adns_query back, next, parent;
37e28fde	100	struct { adns_query head, tail; } children;
37e28fde	101	struct { adns_query back, next; } siblings;
8e5b0abb	102	struct allocnode *allocations;
68442019	103	int interim_allocd;
68442019	104	void *final_allocspace;
0ba0614a	105
0ba0614a	106	const typeinfo *typei;
8e5b0abb	107	char *query_dgram;
8e5b0abb	108	int query_dglen;
31144a72	109
8e5b0abb	110	vbuf vb;
	111	/* General-purpose messing-about buffer.
	112	* Wherever a `big' interface is crossed, this may be corrupted/changed
	113	* unless otherwise specified.
	114	*/
	115
	116	adns_answer *answer;
	117	/* This is allocated when a query is submitted, to avoid being unable
	118	* to relate errors to queries if we run out of memory. During
	119	* query processing status, rrs is 0. cname is set if
	120	* we found a cname (this corresponds to cname_dgram in the query
	121	* structure). type is set from the word go. nrrs and rrs
	122	* are set together, when we find how many rrs there are.
	123	*/
31144a72	124
31144a72	125	byte *cname_dgram;
	126	int cname_dglen, cname_begin;
	127
ddfda861	128	int id, flags, udpretries;
4353a5c4	129	int udpnextserver;
4353a5c4	130	unsigned long udpsent, tcpfailed; /* bitmap indexed by server */
37e28fde	131	struct timeval timeout;
4353a5c4	132	qcontext context;
ddfda861	133
37e28fde	134	/* Possible states:
ddfda861	135	*
8e5b0abb	136	* state Queue child id nextudpserver sentudp failedtcp
	137	*
	138	* udp NONE null >=0 0 zero zero
	139	* udp timew null >=0 any nonzero zero
	140	* udp NONE null >=0 any nonzero zero
	141	*
	142	* tcpwait timew null >=0 irrelevant zero any
	143	* tcpsent timew null >=0 irrelevant zero any
	144	*
	145	* child childw set >=0 irrelevant irrelevant irrelevant
	146	* done output null -1 irrelevant irrelevant irrelevant
ddfda861	147	*
	148	* +------------------------+
	149	* START -----> \| udp/NONE \|
	150	* +------------------------+
	151	* / \|\ \
	152	* too big for UDP / UDP timeout \ \ send via UDP
	153	* do this ASAP! / more retries \ \ do this ASAP!
	154	* \|_ desired \ _\|
	155	* +---------------+ +-----------+
	156	* \| tcpwait/timew \| ____ \| udp/timew \|
	157	* +---------------+ \ +-----------+
	158	* \| ^ \| \| \|
	159	* TCP conn'd; \| \| TCP died \| \| \|
	160	* send via TCP \| \| more \| UDP timeout \| \|
	161	* do this ASAP! \| \| servers \| no more \| \|
	162	* v \| to try \| retries \| \|
	163	* +---------------+ \| desired \| \|
	164	* \| tcpsent/timew \| ____ \| \| \|
	165	* +---------------+ \\| \| \|
	166	* \ \ TCP died \| TCP \| \|
	167	* \ \ no more \| timeout / \|
	168	* \ \ servers \| / \|
	169	* \ \ to try \| / \|
	170	* got \ \ v \|_ / got
	171	* reply \ _\| +------------------+ / reply
	172	* \ \| done/output FAIL \| /
	173	* \ +------------------+ /
	174	* \ /
	175	* _\| \|_
	176	* (..... got reply ....)
	177	* / \
	178	* need child query/ies / \ no child query
	179	* / \
	180	* \|_ _\|
	181	* +--------------+ +----------------+
	182	* \| child/childw \| ----------------> \| done/output OK \|
	183	* +--------------+ children done +----------------+
37e28fde	184	*/
	185	};
	186
37e28fde	187	struct adns__state {
37e28fde	188	adns_initflags iflags;
37e28fde	189	FILE *diagfile;
ddfda861	190	struct { adns_query head, tail; } timew, childw, output;
4353a5c4	191	int nextid, udpsocket, tcpsocket;
8e5b0abb	192	vbuf tcpsend, tcprecv;
37e28fde	193	int nservers, tcpserver;
8402e34c	194	enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate;
37e28fde	195	struct timeval tcptimeout;
	196	struct server {
	197	struct in_addr addr;
	198	} servers[MAXSERVERS];
	199	};
	200
	201	/* From setup.c: */
	202
4353a5c4	203	void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent,
68442019	204	int serv, adns_query qu, const char *fmt, va_list al);
31144a72	205
31144a72	206	void adns__debug(adns_state ads, int serv, adns_query qu,
68442019	207	const char *fmt, ...) PRINTFFORMAT(4,5);
31144a72	208	void adns__warn(adns_state ads, int serv, adns_query qu,
68442019	209	const char *fmt, ...) PRINTFFORMAT(4,5);
31144a72	210	void adns__diag(adns_state ads, int serv, adns_query qu,
68442019	211	const char *fmt, ...) PRINTFFORMAT(4,5);
37e28fde	212
4353a5c4	213	int adns__vbuf_ensure(vbuf *vb, int want);
31144a72	214	int adns__vbuf_appendstr(vbuf vb, const char data);
4353a5c4	215	int adns__vbuf_append(vbuf vb, const byte data, int len);
ddfda861	216	/* 1=>success, 0=>realloc failed */
4353a5c4	217	void adns__vbuf_appendq(vbuf vb, const byte data, int len);
4353a5c4	218	void adns__vbuf_init(vbuf *vb);
8e5b0abb	219	void adns__vbuf_free(vbuf *vb);
4353a5c4	220
4353a5c4	221	int adns__setnonblock(adns_state ads, int fd); /* => errno value */
ddfda861	222
37e28fde	223	/* From submit.c: */
37e28fde	224
8e5b0abb	225	int adns__internal_submit(adns_state ads, adns_query *query_r,
68442019	226	adns_rrtype type, vbuf *qumsg_vb, int id,
8e5b0abb	227	adns_queryflags flags, struct timeval now,
	228	adns_status failstat, const qcontext *ctx);
	229	/* Submits a query (for internal use, called during external submits).
	230	*
	231	* The new query is returned in *query_r, or we return adns_s_nomemory.
	232	*
68442019	233	* The query datagram should already have been assembled in qumsg_vb;
	234	* the memory for it is _taken over_ by this routine whether it
	235	* succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
8e5b0abb	236	*
	237	* If failstat is nonzero then if we are successful in creating the query
	238	* it is immediately failed with code failstat (but _submit still succeds).
	239	*
	240	* ctx is copied byte-for-byte into the query.
	241	*/
	242
	243	void *adns__alloc_interim(adns_query qu, size_t sz);
	244	/* Allocates some memory, and records which query it came from
	245	* and how much there was.
	246	*
	247	* If an error occurs in the query, all its memory is simply freed.
	248	*
	249	* If the query succeeds, one large buffer will be made which is
	250	* big enough for all these allocations, and then adns__alloc_final
	251	* will get memory from this buffer.
	252	*
	253	* _alloc_interim can fail, in which case it will fail the query too,
	254	* so nothing more need be done with it.
	255	*/
	256
	257	void *adns__alloc_final(adns_query qu, size_t sz);
	258	/* Cannot fail.
	259	*/
37e28fde	260
68442019	261	void adns__makefinal_block(adns_query qu, void **blpp, size_t sz);
	262	void adns__makefinal_str(adns_query qu, char **strp);
	263
37e28fde	264	/* From query.c: */
37e28fde	265
ddfda861	266	void adns__query_udp(adns_state ads, adns_query qu, struct timeval now);
ddfda861	267	void adns__query_tcp(adns_state ads, adns_query qu, struct timeval now);
68442019	268	adns_status adns__mkquery(adns_state ads, vbuf *vb,
68442019	269	const char owner, int ol, int id_r,
98a3f706	270	const typeinfo *typei, adns_queryflags flags);
68442019	271	/* Assembles a query packet in vb, and returns id at id_r. /
4353a5c4	272
8e5b0abb	273	void adns__query_ok(adns_state ads, adns_query qu);
	274	void adns__query_fail(adns_state ads, adns_query qu, adns_status stat);
	275
68442019	276	void adns__reset_cnameonly(adns_state ads, adns_query qu);
	277	/* Resets all of the memory management stuff etc. to
	278	* take account of only the CNAME. Used when we find an error somewhere
	279	* and want to just report the error (with perhaps CNAME info), and also
	280	* when we're halfway through RRs in a datagram and discover that we
	281	* need to retry the query.
	282	*/
	283
4353a5c4	284	/* From reply.c: */
4353a5c4	285
98a3f706	286	void adns__procdgram(adns_state ads, const byte *dgram, int len,
	287	int serv, struct timeval now);
	288
	289	/* From types.c: */
	290
	291	const typeinfo *adns__findtype(adns_rrtype type);
	292
	293	/* From parse.c: */
	294
f1e474dd	295	typedef struct {
68442019	296	adns_state ads;
68442019	297	int serv;
f1e474dd	298	const byte *dgram;
	299	int dglen, max, cbyte, namelen;
	300	int dmend_rlater, namelen_rlater;
	301	} findlabel_state;
	302
	303	void adns__findlabel_start(findlabel_state *fls,
	304	adns_state ads, int serv,
	305	const byte *dgram, int dglen, int max,
	306	int dmbegin, int *dmend_rlater);
	307	/* Finds labels in a domain in a datagram.
	308	*
	309	* Call this routine first.
	310	* endpoint_rlater may be null.
	311	*/
	312
	313	adns_status adns__findlabel_next(findlabel_state *fls,
	314	int lablen_r, int labstart_r);
	315	/* Then, call this one repeatedly.
	316	*
	317	* It will return adns_s_ok if all is well, and tell you the length
	318	* and start of successive labels. labstart_r may be null, but
	319	* lablen_r must not be.
	320	*
	321	* After the last label, it will return with *lablen_r zero.
	322	* Do not then call it again; instead, just throw away the findlabel_state.
	323	*
	324	* *dmend_rlater will have been set to point to the next part of
	325	* the datagram after the label (or after the uncompressed part,
	326	* if compression was used). *namelen_rlater will have been set
	327	* to the length of the domain name (total length of labels plus
	328	* 1 for each intervening dot).
	329	*
	330	* If the datagram appears to be truncated, *lablen_r will be -1.
	331	* dmend_rlater, labstart_r and *namelen_r may contain garbage.
	332	* Do not call _next again.
	333	*
	334	* There may also be errors, in which case *dmend_rlater,
	335	* namelen_rlater, lablen_r and *labstart_r may contain garbage.
	336	* Do not then call findlabel_next again.
	337	*/
	338
	339	adns_status adns__parse_domain(adns_state ads, int serv, vbuf *vb,
	340	const byte *dgram, int dglen,
	341	int *cbyte_io, int max);
	342	/* vb must already have been initialised; it will be reset if necessary.
	343	* If there is truncation, vb->used will be set to 0; otherwise
	344	* (if there is no error) vb will be null-terminated.
	345	* If there is an error vb and *cbyte_io may be left indeterminate.
	346	*/
	347
	348	adns_status adns__findrr(adns_state ads, int serv,
	349	const byte dgram, int dglen, int cbyte_io,
	350	int type_r, int class_r, int rdlen_r, int rdstart_r,
	351	const byte *eo_dgram, int eo_dglen, int eo_cbyte,
	352	int *eo_matched_r);
	353	/* Finds the extent and some of the contents of an RR in a datagram
	354	* and does some checks. The datagram is *dgram, length dglen, and
	355	* the RR starts at *cbyte_io (which is updated afterwards to point
	356	* to the end of the RR).
	357	*
	358	* The type, class and RRdata length and start are returned iff
	359	* the corresponding pointer variables are not null. type_r and
	360	* class_r may not be null.
	361	*
362	* If the caller thinks they know what the owner of the RR ought to
363	* be they can pass in details in eo_*: this is another (or perhaps
364	* the same datagram), and a pointer to where the putative owner
365	* starts in that datagram. In this case *eo_matched_r will be set
366	* to 1 if the datagram matched or 0 if it did not. Either
367	* both eo_dgram and eo_matched_r must both be non-null, or they
368	* must both be null (in which case eo_dglen and eo_cbyte will be ignored).
369	* The eo datagram and contained owner domain MUST be valid and
370	* untruncated.
371	*
372	* If there is truncation then *type_r will be set to -1 and
373	* cbyte_io, class_r, rdlen_r, rdstart_r and *eo_matched_r will be
374	* undefined.
375	*
376	* If an error is returned then *type_r will be undefined too.
377	*/
98a3f706	378
f1e474dd	379	int vbuf__append_quoted1035(vbuf vb, const byte buf, int len);
8402e34c	380
8402e34c	381	/* From event.c: */
4353a5c4	382
8402e34c	383	void adns__tcp_broken(adns_state ads, const char what, const char why);
4353a5c4	384	void adns__tcp_tryconnect(adns_state ads, struct timeval now);
4353a5c4	385	void adns__autosys(adns_state ads, struct timeval now);
37e28fde	386
	387	/* Useful static inline functions: */
	388
	389	static inline void timevaladd(struct timeval *tv_io, long ms) {
	390	struct timeval tmp;
	391	assert(ms>=0);
	392	tmp= *tv_io;
94436798	393	tmp.tv_usec += (ms%1000)*1000000;
37e28fde	394	tmp.tv_sec += ms/1000;
94436798	395	if (tmp.tv_usec >= 1000000) { tmp.tv_sec++; tmp.tv_usec -= 1000; }
37e28fde	396	*tv_io= tmp;
ddfda861	397	}
37e28fde	398
	399	static inline int ctype_whitespace(int c) { return c==' ' \|\| c=='\n' \|\| c=='\t'; }
	400	static inline int ctype_digit(int c) { return c>='0' && c<='9'; }
98a3f706	401	static inline int ctype_alpha(int c) {
	402	return (c >= 'a' && c <= 'z') \|\| (c >= 'A' \|\| c <= 'Z');
	403	}
37e28fde	404
	405	/* Useful macros */
	406
8e5b0abb	407	#define MEM_ROUND(sz) \
	408	(( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
	409	* sizeof(union maxalign) )
	410
4353a5c4	411	#define LIST_INIT(list) ((list).head= (list).tail= 0)
4353a5c4	412
37e28fde	413	#define LIST_UNLINK_PART(list,node,part) \
	414	do { \
	415	if ((node)->back) (node)->back->part next= (node)->part next; \
	416	else (list).head= (node)->part next; \
	417	if ((node)->next) (node)->next->part back= (node)->part back; \
	418	else (list).tail= (node)->part back; \
	419	} while(0)
	420
	421	#define LIST_LINK_TAIL_PART(list,node,part) \
	422	do { \
	423	(node)->part back= 0; \
	424	(node)->part next= (list).tail; \
	425	if ((list).tail) (list).tail->part back= (node); else (list).part head= (node); \
	426	(list).tail= (node); \
	427	} while(0)
	428
	429	#define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
4353a5c4	430	#define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)
37e28fde	431
98a3f706	432	#define GETIL_B(cb) (dgram[(cb)++])
	433	#define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
	434	#define GET_W(cb,tv) ((tv)=0, (tv)\|=(GETIL_B((cb))<<8), (tv)\|=GETIL_B(cb), (tv))
	435
37e28fde	436	#endif