[adns] / src / adns.c

/**/

#include <stdarg.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <unistd.h>

#include <netdb.h>
#include <arpa/nameser.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "adns-internal.h"

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

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

static void vdebug(adns_state ads, const char *fmt, va_list al) {
  if (!(ads->iflags & adns_if_debug)) return;
  fputs("adns debug: ",stderr);
  vfprintf(stderr,fmt,al);
  fputc('\n',stderr);
}

static void debug(adns_state ads, const char *fmt, ...) {
  va_list al;

  va_start(al,fmt);
  vdebug(ads,fmt,al);
  va_end(al);
}

static void vdiag(adns_state ads, const char *fmt, va_list al) {
  if (ads->iflags & adns_if_noerrprint) return;
  fputs("adns: ",stderr);
  vfprintf(stderr,fmt,al);
  fputc('\n',stderr);
}

static void diag(adns_state ads, const char *fmt, ...) {
  va_list al;

  va_start(al,fmt);
  vdiag(ads,fmt,al);
  va_end(al);
}

static void addserver(adns_state ads, struct in_addr addr) {
  int i;
  struct server *ss;
  
  for (i=0; i<ads->nservers; i++) {
    if (ads->servers[i].addr.s_addr == addr.s_addr) {
      debug(ads,"duplicate nameserver %s ignored",inet_ntoa(addr));
      return;
    }
  }
  
  if (ads->nservers>=MAXSERVERS) {
    diag(ads,"too many nameservers, ignoring %s",inet_ntoa(addr));
    return;
  }

  ss= ads->servers+ads->nservers;
  ss->addr= addr;
  ss->state= server_disc;
  ss->connw.head= ss->connw.tail= 0;
  ads->nservers++;
}

static void configparseerr(adns_state ads, const char *fn, int lno,
			   const char *fmt, ...) {
  va_list al;
  
  if (ads->iflags & adns_if_noerrprint) return;
  if (lno==-1) fprintf(stderr,"adns: %s: ",fn);
  else fprintf(stderr,"adns: %s:%d: ",fn,lno);
  va_start(al,fmt);
  vfprintf(stderr,fmt,al);
  va_end(al);
  fputc('\n',stderr);
}

static void ccf_nameserver(adns_state ads, const char *fn, int lno, const char *buf) {
  struct in_addr ia;
  
  if (!inet_aton(buf,&ia)) {
    configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
    return;
  }
  debug(ads,"using nameserver %s",inet_ntoa(ia));
  addserver(ads,ia);
}

static void ccf_search(adns_state ads, const char *fn, int lno, const char *buf) {
  if (!buf) return;
  diag(ads,"warning - `search' ignored FIXME");
}

static void ccf_sortlist(adns_state ads, const char *fn, int lno, const char *buf) {
  diag(ads,"warning - `sortlist' ignored FIXME");
}

static void ccf_options(adns_state ads, const char *fn, int lno, const char *buf) {
  if (!buf) return;
  diag(ads,"warning - `options' ignored FIXME");
}

static void ccf_clearnss(adns_state ads, const char *fn, int lno, const char *buf) {
  ads->nservers= 0;
}

static const struct configcommandinfo {
  const char *name;
  void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
} configcommandinfos[]= {
  { "nameserver",        ccf_nameserver  },
  { "domain",            ccf_search      },
  { "search",            ccf_search      },
  { "sortlist",          ccf_sortlist    },
  { "options",           ccf_options     },
  { "clearnameservers",  ccf_clearnss    },
  {  0                                   }
};

static int ctype_whitespace(int c) { return c==' ' || c=='\n' || c=='\t'; }
static int ctype_digit(int c) { return c>='0' && c<='9'; }

static void readconfig(adns_state ads, const char *filename) {
  char linebuf[2000], *p, *q;
  FILE *file;
  int lno, l, c;
  const struct configcommandinfo *ccip;

  file= fopen(filename,"r");
  if (!file) {
    if (errno == ENOENT) {
      debug(ads,"configuration file `%s' does not exist",filename);
      return;
    }
    diag(ads,"cannot open configuration file `%s': %s",filename,strerror(errno));
    return;
  }

  for (lno=1; fgets(linebuf,sizeof(linebuf),file); lno++) {
    l= strlen(linebuf);
    if (!l) continue;
    if (linebuf[l-1] != '\n' && !feof(file)) {
      diag(ads,"%s:%d: line too long",filename,lno);
      while ((c= getc(file)) != EOF && c != '\n') { }
      if (c == EOF) break;
      continue;
    }
    while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
    linebuf[l]= 0;
    p= linebuf;
    while (ctype_whitespace(*p)) p++;
    if (*p == '#' || *p == '\n') continue;
    q= p;
    while (*q && !ctype_whitespace(*q)) q++;
    for (ccip=configcommandinfos;
	 ccip->name && strncmp(ccip->name,p,q-p);
	 ccip++);
    if (!ccip->name) {
      diag(ads,"%s:%d: unknown configuration directive `%.*s'",filename,lno,q-p,p);
      continue;
    }
    while (ctype_whitespace(*q)) q++;
    ccip->fn(ads,filename,lno,q);
  }
  if (ferror(file)) {
    diag(ads,"%s:%d: read error: %s",filename,lno,strerror(errno));
  }
  fclose(file);
}

static const char *instrum_getenv(adns_state ads, const char *envvar) {
  const char *value;

  value= getenv(envvar);
  if (!value) debug(ads,"environment variable %s not set",envvar);
  else debug(ads,"environment variable %s set to `%s'",envvar,value);
  return value;
}

static void readconfigenv(adns_state ads, const char *envvar) {
  const char *filename;

  if (ads->iflags & adns_if_noenv) {
    debug(ads,"not checking environment variable `%s'",envvar);
    return;
  }
  filename= instrum_getenv(ads,envvar);
  if (filename) readconfig(ads,filename);
}
  
int adns_init(adns_state *ads_r, adns_initflags flags) {
  adns_state ads;
  const char *res_options, *adns_res_options;
  struct protoent *proto;
  int r;
  
  ads= malloc(sizeof(*ads)); if (!ads) return errno;
  ads->input.head= ads->input.tail= 0;
  ads->timew.head= ads->timew.tail= 0;
  ads->childw.head= ads->childw.tail= 0;
  ads->output.head= ads->output.tail= 0;
  ads->nextid= 0x311f;
  ads->udpsocket= -1;
  ads->qbufavail= 0;
  ads->qbuf= 0;
  ads->tcpbufavail= ads->tcpbufused= ads->tcpbufdone= 0;
  ads->tcpbuf= 0;
  ads->iflags= flags;
  ads->nservers= 0;
  ads->iflags= flags;

  res_options= instrum_getenv(ads,"RES_OPTIONS");
  adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
  ccf_options(ads,"RES_OPTIONS",-1,res_options);
  ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);

  readconfig(ads,"/etc/resolv.conf");
  readconfigenv(ads,"RES_CONF");
  readconfigenv(ads,"ADNS_RES_CONF");

  ccf_options(ads,"RES_OPTIONS",-1,res_options);
  ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);

  ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
  ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));

  if (!ads->nservers) {
    struct in_addr ia;
    if (ads->iflags & adns_if_debug)
      fprintf(stderr,"adns: no nameservers, using localhost\n");
    ia.s_addr= INADDR_LOOPBACK;
    addserver(ads,ia);
  }

  proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
  ads->udpsocket= socket(AF_INET,SOCK_DGRAM,proto->p_proto);
  if (!ads->udpsocket) { r= errno; goto x_closeudp; }
  
  *ads_r= ads;
  return 0;

 x_closeudp:
  close(ads->udpsocket);
 x_free:
  free(ads);
  return r;
}

static void query_fail(adns_state ads, adns_query qu, adns_status stat) {
  adns_answer *ans;
  
  ans= qu->answer;
  if (!ans) ans= malloc(sizeof(*qu->answer));
  if (ans) {
    ans->status= stat;
    ans->cname= 0;
    ans->type= qu->type;
    ans->nrrs= 0;
  }
  qu->answer= ans;
  LIST_LINK_TAIL(ads->input,qu);
}

int adns_finish(adns_state ads) {
  abort(); /* FIXME */
}

void adns_interest(adns_state ads, int *maxfd,
		   fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
		   struct timeval **tv_io, struct timeval *tvbuf) {
  abort(); /* FIXME */
}

static void autosys(adns_state ads) {
  if (ads->iflags & adns_if_noautosys) return;
  adns_callback(ads,-1,0,0,0);
}

void adns_cancel(adns_state ads, adns_query query) {
  abort(); /* FIXME */
}

int adns_callback(adns_state ads, int maxfd,
		  const fd_set *readfds, const fd_set *writefds,
		  const fd_set *exceptfds) {
  abort(); /* FIXME */
}

static int internal_check(adns_state ads,
			  adns_query *query_io,
			  adns_answer *answer,
			  void *context_r) {
  abort(); /* FIXME */
}

int adns_wait(adns_state ads,
	      adns_query *query_io,
	      adns_answer *answer,
	      void *context_r) {
  int r, maxfd, rsel, rcb;
  fd_set readfds, writefds, exceptfds;
  struct timeval tvbuf, *tvp;
  
  for (;;) {
    r= internal_check(ads,query_io,answer,context_r);
    if (r && r != EWOULDBLOCK) return r;
    FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds);
    maxfd= 0; tvp= 0;
    adns_interest(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf);
    rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp);
    if (rsel==-1) return r;
    rcb= adns_callback(ads,maxfd,&readfds,&writefds,&exceptfds);
    assert(rcb==rsel);
  }
}

int adns_check(adns_state ads,
	       adns_query *query_io,
	       adns_answer *answer,
	       void *context_r) {
  autosys(ads);
  return internal_check(ads,query_io,answer,context_r);
}

int adns_synchronous(adns_state ads,
		     const char *owner,
		     adns_rrtype type,
		     adns_queryflags flags,
		     adns_answer *answer) {
  adns_query qu;
  int r;
  
  r= adns_submit(ads,owner,type,flags,0,&qu);
  if (r) return r;

  do {
    r= adns_wait(ads,&qu,answer,0);
  } while (r==EINTR);
  if (r) adns_cancel(ads,qu);
  return r;
}

static adns_status mkquery(adns_state ads, const char *owner, int ol, int id,
			   adns_rrtype type, adns_queryflags flags, int *qml_r) {
  int ll, c, nlabs, qbufreq;
  unsigned char label[255], *nqbuf;
  const char *p, *pe;

#define MKQUERY_ADDB(b) *nqbuf++= (b)
#define MKQUERY_ADDW(w) (MKQUERY_ADDB(((w)>>8)&0x0ff), MKQUERY_ADDB((w)&0x0ff))

  qbufreq= 12+strlen(owner)+3;
  if (ads->qbufavail < qbufreq) {
    nqbuf= realloc(ads->qbuf,qbufreq);
    if (!nqbuf) return adns_s_nolocalmem;
    ads->qbuf= nqbuf; ads->qbufavail= qbufreq;
  }
  nqbuf= ads->qbuf;
  
  MKQUERY_ADDW(id);
  MKQUERY_ADDB(0x01); /* QR=Q(0), OPCODE=QUERY(0000), !AA, !TC, RD */
  MKQUERY_ADDB(0x00); /* !RA, Z=000, RCODE=NOERROR(0000) */
  MKQUERY_ADDW(1); /* QDCOUNT=1 */
  MKQUERY_ADDW(0); /* ANCOUNT=0 */
  MKQUERY_ADDW(0); /* NSCOUNT=0 */
  MKQUERY_ADDW(0); /* ARCOUNT=0 */
  p= owner; pe= owner+ol;
  nlabs= 0;
  if (!*p) return adns_s_invaliddomain;
  do {
    ll= 0;
    while (p!=pe && (c= *p++)!='.') {
      if (c=='\\') {
	if (!(flags & adns_f_anyquote)) return adns_s_invaliddomain;
	if (ctype_digit(p[0])) {
	  if (ctype_digit(p[1]) && ctype_digit(p[2])) {
	    c= (*p++ - '0')*100 + (*p++ - '0')*10 + (*p++ - '0');
	    if (c >= 256) return adns_s_invaliddomain;
	  } else {
	    return adns_s_invaliddomain;
	  }
	} else if (!(c= *p++)) {
	  return adns_s_invaliddomain;
	}
      }
      if (!(flags & adns_f_anyquote)) {
	if ((c >= '0' && c <= '9') || c == '-') {
	  if (!ll) return adns_s_invaliddomain;
	} else if ((c < 'a' || c > 'z') && (c < 'A' && c > 'Z')) {
	  return adns_s_invaliddomain;
	}
      }
      if (ll == sizeof(label)) return adns_s_invaliddomain;
      label[ll++]= c;
    }
    if (!ll) return adns_s_invaliddomain;
    if (nlabs++ > 63) return adns_s_invaliddomain;
    MKQUERY_ADDB(ll);
    memcpy(nqbuf,label,ll); nqbuf+= ll;
  } while (p!=pe);

  MKQUERY_ADDB(0);
  MKQUERY_ADDW(type & adns__rrt_typemask); /* QTYPE */
  MKQUERY_ADDW(1); /* QCLASS=IN */

  *qml_r= nqbuf - ads->qbuf;
  
  return adns_s_ok;
}

static adns_query allocquery(adns_state ads, const char *owner, int ol,
			     int qml, int id, adns_rrtype type,
			     adns_queryflags flags, void *context) {
  adns_query qu;
  unsigned char *qm;
  
  qu= malloc(sizeof(*qu)+ol+1+qml); if (!qu) return 0;
  qu->next= qu->back= qu->parent= qu->child= 0;
  qu->id= id;
  qu->type= type;
  qu->answer= 0;
  qu->flags= flags;
  qu->context= context;
  qu->udpretries= 0;
  qu->sentudp= qu->senttcp= 0;
  qu->nextserver= 0;
  memcpy(qu->owner,owner,ol); qu->owner[ol]= 0;
  qu->querymsg= qm= qu->owner+ol+1;
  memcpy(qm,ads->qbuf,qml);
  qu->querylen= qml;
  return qu;
}

static int failsubmit(adns_state ads, void *context, adns_query *query_r,
		      adns_rrtype type, adns_queryflags flags,
		      int id, adns_status stat) {
  adns_query qu;

  qu= allocquery(ads,0,0,0,id,type,flags,context); if (!qu) return errno;
  query_fail(ads,qu,stat);
  *query_r= qu;
  return 0;
}

int adns_submit(adns_state ads,
		const char *owner,
		adns_rrtype type,
		adns_queryflags flags,
		void *context,
		adns_query *query_r) {
  adns_query qu;
  adns_status stat;
  int ol, id, qml;

  id= ads->nextid++;

  ol= strlen(owner);
  if (ol<=1 || ol>MAXDNAME+1)
    return failsubmit(ads,context,query_r,type,flags,id,adns_s_invaliddomain);
  if (owner[ol-1]=='.' && owner[ol-2]!='\\') { flags &= ~adns_f_search; ol--; }

  stat= mkquery(ads,owner,ol,id,type,flags,&qml);
  if (stat) return failsubmit(ads,context,query_r,type,flags,id,stat);

  qu= allocquery(ads,owner,ol,qml,id,type,flags,context); if (!qu) return errno;

  LIST_LINK_TAIL(ads->input,qu);
  autosys(ads);

  *query_r= qu;
  return 0;
}
Commit	Line	Data
a17d3a1d	1	/**/
a17d3a1d	2
964344fc	3	#include <stdarg.h>
	4	#include <stdio.h>
	5	#include <errno.h>
	6	#include <string.h>
	7	#include <stdlib.h>
e8c505a5	8	#include <assert.h>
80917fcc	9	#include <unistd.h>
964344fc	10
80917fcc	11	#include <netdb.h>
a17d3a1d	12	#include <arpa/nameser.h>
964344fc	13	#include <sys/socket.h>
	14	#include <netinet/in.h>
	15	#include <arpa/inet.h>
a17d3a1d	16
	17	#include "adns-internal.h"
	18
	19	#define LIST_UNLINK(list,node) \
	20	do { \
	21	if ((node)->back) (node)->back->next= (node)->next; \
	22	else (list).head= (node)->next; \
	23	if ((node)->next) (node)->next->back= (node)->back; \
	24	else (list).tail= (node)->back; \
	25	} while(0)
	26
	27	#define LIST_LINK_TAIL(list,node) \
	28	do { \
	29	(node)->back= 0; \
	30	(node)->next= (list).tail; \
964344fc	31	if ((list).tail) (list).tail->back= (node); else (list).head= (node); \
a17d3a1d	32	(list).tail= (node); \
	33	} while(0)
	34
964344fc	35	static void vdebug(adns_state ads, const char *fmt, va_list al) {
	36	if (!(ads->iflags & adns_if_debug)) return;
	37	fputs("adns debug: ",stderr);
	38	vfprintf(stderr,fmt,al);
	39	fputc('\n',stderr);
	40	}
	41
	42	static void debug(adns_state ads, const char *fmt, ...) {
	43	va_list al;
	44
	45	va_start(al,fmt);
	46	vdebug(ads,fmt,al);
	47	va_end(al);
	48	}
	49
	50	static void vdiag(adns_state ads, const char *fmt, va_list al) {
	51	if (ads->iflags & adns_if_noerrprint) return;
	52	fputs("adns: ",stderr);
	53	vfprintf(stderr,fmt,al);
	54	fputc('\n',stderr);
	55	}
	56
	57	static void diag(adns_state ads, const char *fmt, ...) {
	58	va_list al;
	59
	60	va_start(al,fmt);
	61	vdiag(ads,fmt,al);
	62	va_end(al);
	63	}
	64
	65	static void addserver(adns_state ads, struct in_addr addr) {
e8c505a5	66	int i;
80917fcc	67	struct server *ss;
e8c505a5	68
	69	for (i=0; i<ads->nservers; i++) {
	70	if (ads->servers[i].addr.s_addr == addr.s_addr) {
	71	debug(ads,"duplicate nameserver %s ignored",inet_ntoa(addr));
	72	return;
	73	}
	74	}
	75
a17d3a1d	76	if (ads->nservers>=MAXSERVERS) {
964344fc	77	diag(ads,"too many nameservers, ignoring %s",inet_ntoa(addr));
e8c505a5	78	return;
a17d3a1d	79	}
e8c505a5	80
80917fcc	81	ss= ads->servers+ads->nservers;
	82	ss->addr= addr;
	83	ss->state= server_disc;
	84	ss->connw.head= ss->connw.tail= 0;
e8c505a5	85	ads->nservers++;
a17d3a1d	86	}
a17d3a1d	87
964344fc	88	static void configparseerr(adns_state ads, const char *fn, int lno,
	89	const char *fmt, ...) {
	90	va_list al;
	91
	92	if (ads->iflags & adns_if_noerrprint) return;
	93	if (lno==-1) fprintf(stderr,"adns: %s: ",fn);
	94	else fprintf(stderr,"adns: %s:%d: ",fn,lno);
	95	va_start(al,fmt);
	96	vfprintf(stderr,fmt,al);
	97	va_end(al);
	98	fputc('\n',stderr);
	99	}
	100
	101	static void ccf_nameserver(adns_state ads, const char fn, int lno, const char buf) {
	102	struct in_addr ia;
	103
	104	if (!inet_aton(buf,&ia)) {
	105	configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
	106	return;
	107	}
	108	debug(ads,"using nameserver %s",inet_ntoa(ia));
	109	addserver(ads,ia);
	110	}
	111
	112	static void ccf_search(adns_state ads, const char fn, int lno, const char buf) {
	113	if (!buf) return;
	114	diag(ads,"warning - `search' ignored FIXME");
	115	}
	116
	117	static void ccf_sortlist(adns_state ads, const char fn, int lno, const char buf) {
	118	diag(ads,"warning - `sortlist' ignored FIXME");
	119	}
	120
	121	static void ccf_options(adns_state ads, const char fn, int lno, const char buf) {
	122	if (!buf) return;
	123	diag(ads,"warning - `options' ignored FIXME");
	124	}
	125
	126	static void ccf_clearnss(adns_state ads, const char fn, int lno, const char buf) {
	127	ads->nservers= 0;
	128	}
	129
	130	static const struct configcommandinfo {
	131	const char *name;
	132	void (fn)(adns_state ads, const char fn, int lno, const char *buf);
	133	} configcommandinfos[]= {
	134	{ "nameserver", ccf_nameserver },
	135	{ "domain", ccf_search },
	136	{ "search", ccf_search },
	137	{ "sortlist", ccf_sortlist },
	138	{ "options", ccf_options },
	139	{ "clearnameservers", ccf_clearnss },
	140	{ 0 }
	141	};
	142
350d37d9	143	static int ctype_whitespace(int c) { return c==' ' \|\| c=='\n' \|\| c=='\t'; }
350d37d9	144	static int ctype_digit(int c) { return c>='0' && c<='9'; }
964344fc	145
	146	static void readconfig(adns_state ads, const char *filename) {
	147	char linebuf[2000], p, q;
	148	FILE *file;
	149	int lno, l, c;
	150	const struct configcommandinfo *ccip;
	151
	152	file= fopen(filename,"r");
	153	if (!file) {
	154	if (errno == ENOENT) {
	155	debug(ads,"configuration file `%s' does not exist",filename);
	156	return;
	157	}
	158	diag(ads,"cannot open configuration file `%s': %s",filename,strerror(errno));
	159	return;
	160	}
	161
	162	for (lno=1; fgets(linebuf,sizeof(linebuf),file); lno++) {
	163	l= strlen(linebuf);
	164	if (!l) continue;
	165	if (linebuf[l-1] != '\n' && !feof(file)) {
	166	diag(ads,"%s:%d: line too long",filename,lno);
	167	while ((c= getc(file)) != EOF && c != '\n') { }
	168	if (c == EOF) break;
	169	continue;
	170	}
350d37d9	171	while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
964344fc	172	linebuf[l]= 0;
964344fc	173	p= linebuf;
350d37d9	174	while (ctype_whitespace(*p)) p++;
964344fc	175	if (p == '#' \|\| p == '\n') continue;
964344fc	176	q= p;
350d37d9	177	while (q && !ctype_whitespace(q)) q++;
964344fc	178	for (ccip=configcommandinfos;
	179	ccip->name && strncmp(ccip->name,p,q-p);
	180	ccip++);
	181	if (!ccip->name) {
	182	diag(ads,"%s:%d: unknown configuration directive `%.*s'",filename,lno,q-p,p);
	183	continue;
	184	}
350d37d9	185	while (ctype_whitespace(*q)) q++;
964344fc	186	ccip->fn(ads,filename,lno,q);
	187	}
	188	if (ferror(file)) {
	189	diag(ads,"%s:%d: read error: %s",filename,lno,strerror(errno));
	190	}
	191	fclose(file);
	192	}
	193
	194	static const char instrum_getenv(adns_state ads, const char envvar) {
	195	const char *value;
	196
	197	value= getenv(envvar);
e8c505a5	198	if (!value) debug(ads,"environment variable %s not set",envvar);
e8c505a5	199	else debug(ads,"environment variable %s set to `%s'",envvar,value);
964344fc	200	return value;
a17d3a1d	201	}
a17d3a1d	202
964344fc	203	static void readconfigenv(adns_state ads, const char *envvar) {
a17d3a1d	204	const char *filename;
a17d3a1d	205
964344fc	206	if (ads->iflags & adns_if_noenv) {
	207	debug(ads,"not checking environment variable `%s'",envvar);
	208	return;
	209	}
	210	filename= instrum_getenv(ads,envvar);
	211	if (filename) readconfig(ads,filename);
a17d3a1d	212	}
a17d3a1d	213
964344fc	214	int adns_init(adns_state *ads_r, adns_initflags flags) {
a17d3a1d	215	adns_state ads;
964344fc	216	const char res_options, adns_res_options;
80917fcc	217	struct protoent *proto;
350d37d9	218	int r;
a17d3a1d	219
a17d3a1d	220	ads= malloc(sizeof(*ads)); if (!ads) return errno;
964344fc	221	ads->input.head= ads->input.tail= 0;
a17d3a1d	222	ads->timew.head= ads->timew.tail= 0;
964344fc	223	ads->childw.head= ads->childw.tail= 0;
964344fc	224	ads->output.head= ads->output.tail= 0;
80917fcc	225	ads->nextid= 0x311f;
a17d3a1d	226	ads->udpsocket= -1;
	227	ads->qbufavail= 0;
	228	ads->qbuf= 0;
	229	ads->tcpbufavail= ads->tcpbufused= ads->tcpbufdone= 0;
	230	ads->tcpbuf= 0;
964344fc	231	ads->iflags= flags;
a17d3a1d	232	ads->nservers= 0;
964344fc	233	ads->iflags= flags;
	234
	235	res_options= instrum_getenv(ads,"RES_OPTIONS");
	236	adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
	237	ccf_options(ads,"RES_OPTIONS",-1,res_options);
	238	ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
a17d3a1d	239
	240	readconfig(ads,"/etc/resolv.conf");
	241	readconfigenv(ads,"RES_CONF");
	242	readconfigenv(ads,"ADNS_RES_CONF");
964344fc	243
	244	ccf_options(ads,"RES_OPTIONS",-1,res_options);
	245	ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
	246
	247	ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
	248	ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
	249
a17d3a1d	250	if (!ads->nservers) {
964344fc	251	struct in_addr ia;
964344fc	252	if (ads->iflags & adns_if_debug)
a17d3a1d	253	fprintf(stderr,"adns: no nameservers, using localhost\n");
964344fc	254	ia.s_addr= INADDR_LOOPBACK;
964344fc	255	addserver(ads,ia);
a17d3a1d	256	}
80917fcc	257
	258	proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
	259	ads->udpsocket= socket(AF_INET,SOCK_DGRAM,proto->p_proto);
	260	if (!ads->udpsocket) { r= errno; goto x_closeudp; }
a17d3a1d	261
	262	*ads_r= ads;
	263	return 0;
80917fcc	264
	265	x_closeudp:
	266	close(ads->udpsocket);
	267	x_free:
	268	free(ads);
	269	return r;
a17d3a1d	270	}
a17d3a1d	271
964344fc	272	static void query_fail(adns_state ads, adns_query qu, adns_status stat) {
e8c505a5	273	adns_answer *ans;
a17d3a1d	274
	275	ans= qu->answer;
	276	if (!ans) ans= malloc(sizeof(*qu->answer));
	277	if (ans) {
	278	ans->status= stat;
	279	ans->cname= 0;
	280	ans->type= qu->type;
	281	ans->nrrs= 0;
	282	}
	283	qu->answer= ans;
964344fc	284	LIST_LINK_TAIL(ads->input,qu);
a17d3a1d	285	}
a17d3a1d	286
80917fcc	287	int adns_finish(adns_state ads) {
	288	abort(); /* FIXME */
	289	}
	290
e8c505a5	291	void adns_interest(adns_state ads, int *maxfd,
964344fc	292	fd_set readfds, fd_set writefds, fd_set *exceptfds,
e8c505a5	293	struct timeval *tv_io, struct timeval tvbuf) {
964344fc	294	abort(); /* FIXME */
a17d3a1d	295	}
a17d3a1d	296
e8c505a5	297	static void autosys(adns_state ads) {
	298	if (ads->iflags & adns_if_noautosys) return;
	299	adns_callback(ads,-1,0,0,0);
	300	}
	301
	302	void adns_cancel(adns_state ads, adns_query query) {
	303	abort(); /* FIXME */
	304	}
	305
	306	int adns_callback(adns_state ads, int maxfd,
	307	const fd_set readfds, const fd_set writefds,
	308	const fd_set *exceptfds) {
	309	abort(); /* FIXME */
	310	}
	311
	312	static int internal_check(adns_state ads,
	313	adns_query *query_io,
	314	adns_answer *answer,
	315	void *context_r) {
	316	abort(); /* FIXME */
	317	}
	318
	319	int adns_wait(adns_state ads,
	320	adns_query *query_io,
	321	adns_answer *answer,
	322	void *context_r) {
	323	int r, maxfd, rsel, rcb;
	324	fd_set readfds, writefds, exceptfds;
	325	struct timeval tvbuf, *tvp;
	326
	327	for (;;) {
	328	r= internal_check(ads,query_io,answer,context_r);
	329	if (r && r != EWOULDBLOCK) return r;
	330	FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds);
	331	maxfd= 0; tvp= 0;
	332	adns_interest(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf);
	333	rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp);
	334	if (rsel==-1) return r;
	335	rcb= adns_callback(ads,maxfd,&readfds,&writefds,&exceptfds);
	336	assert(rcb==rsel);
	337	}
	338	}
	339
	340	int adns_check(adns_state ads,
	341	adns_query *query_io,
	342	adns_answer *answer,
	343	void *context_r) {
	344	autosys(ads);
	345	return internal_check(ads,query_io,answer,context_r);
	346	}
	347
	348	int adns_synchronous(adns_state ads,
	349	const char *owner,
	350	adns_rrtype type,
72934832	351	adns_queryflags flags,
e8c505a5	352	adns_answer *answer) {
	353	adns_query qu;
	354	int r;
	355
	356	r= adns_submit(ads,owner,type,flags,0,&qu);
	357	if (r) return r;
	358
72934832	359	do {
	360	r= adns_wait(ads,&qu,answer,0);
	361	} while (r==EINTR);
e8c505a5	362	if (r) adns_cancel(ads,qu);
	363	return r;
	364	}
	365
350d37d9	366	static adns_status mkquery(adns_state ads, const char *owner, int ol, int id,
	367	adns_rrtype type, adns_queryflags flags, int *qml_r) {
	368	int ll, c, nlabs, qbufreq;
	369	unsigned char label[255], *nqbuf;
	370	const char p, pe;
	371
	372	#define MKQUERY_ADDB(b) *nqbuf++= (b)
	373	#define MKQUERY_ADDW(w) (MKQUERY_ADDB(((w)>>8)&0x0ff), MKQUERY_ADDB((w)&0x0ff))
	374
	375	qbufreq= 12+strlen(owner)+3;
	376	if (ads->qbufavail < qbufreq) {
	377	nqbuf= realloc(ads->qbuf,qbufreq);
	378	if (!nqbuf) return adns_s_nolocalmem;
	379	ads->qbuf= nqbuf; ads->qbufavail= qbufreq;
	380	}
	381	nqbuf= ads->qbuf;
	382
	383	MKQUERY_ADDW(id);
	384	MKQUERY_ADDB(0x01); /* QR=Q(0), OPCODE=QUERY(0000), !AA, !TC, RD */
	385	MKQUERY_ADDB(0x00); /* !RA, Z=000, RCODE=NOERROR(0000) */
	386	MKQUERY_ADDW(1); /* QDCOUNT=1 */
	387	MKQUERY_ADDW(0); /* ANCOUNT=0 */
	388	MKQUERY_ADDW(0); /* NSCOUNT=0 */
	389	MKQUERY_ADDW(0); /* ARCOUNT=0 */
	390	p= owner; pe= owner+ol;
	391	nlabs= 0;
	392	if (!*p) return adns_s_invaliddomain;
	393	do {
	394	ll= 0;
	395	while (p!=pe && (c= *p++)!='.') {
	396	if (c=='\\') {
	397	if (!(flags & adns_f_anyquote)) return adns_s_invaliddomain;
	398	if (ctype_digit(p[0])) {
	399	if (ctype_digit(p[1]) && ctype_digit(p[2])) {
	400	c= (p++ - '0')100 + (p++ - '0')10 + (*p++ - '0');
	401	if (c >= 256) return adns_s_invaliddomain;
	402	} else {
	403	return adns_s_invaliddomain;
	404	}
	405	} else if (!(c= *p++)) {
	406	return adns_s_invaliddomain;
	407	}
	408	}
	409	if (!(flags & adns_f_anyquote)) {
	410	if ((c >= '0' && c <= '9') \|\| c == '-') {
	411	if (!ll) return adns_s_invaliddomain;
	412	} else if ((c < 'a' \|\| c > 'z') && (c < 'A' && c > 'Z')) {
	413	return adns_s_invaliddomain;
	414	}
	415	}
	416	if (ll == sizeof(label)) return adns_s_invaliddomain;
	417	label[ll++]= c;
	418	}
	419	if (!ll) return adns_s_invaliddomain;
	420	if (nlabs++ > 63) return adns_s_invaliddomain;
	421	MKQUERY_ADDB(ll);
	422	memcpy(nqbuf,label,ll); nqbuf+= ll;
	423	} while (p!=pe);
	424
	425	MKQUERY_ADDB(0);
	426	MKQUERY_ADDW(type & adns__rrt_typemask); /* QTYPE */
	427	MKQUERY_ADDW(1); /* QCLASS=IN */
	428
	429	*qml_r= nqbuf - ads->qbuf;
430
431	return adns_s_ok;
80917fcc	432	}
80917fcc	433
350d37d9	434	static adns_query allocquery(adns_state ads, const char *owner, int ol,
	435	int qml, int id, adns_rrtype type,
	436	adns_queryflags flags, void *context) {
a17d3a1d	437	adns_query qu;
350d37d9	438	unsigned char *qm;
	439
	440	qu= malloc(sizeof(*qu)+ol+1+qml); if (!qu) return 0;
a17d3a1d	441	qu->next= qu->back= qu->parent= qu->child= 0;
350d37d9	442	qu->id= id;
a17d3a1d	443	qu->type= type;
	444	qu->answer= 0;
	445	qu->flags= flags;
	446	qu->context= context;
964344fc	447	qu->udpretries= 0;
80917fcc	448	qu->sentudp= qu->senttcp= 0;
80917fcc	449	qu->nextserver= 0;
a17d3a1d	450	memcpy(qu->owner,owner,ol); qu->owner[ol]= 0;
350d37d9	451	qu->querymsg= qm= qu->owner+ol+1;
	452	memcpy(qm,ads->qbuf,qml);
	453	qu->querylen= qml;
	454	return qu;
	455	}
80917fcc	456
350d37d9	457	static int failsubmit(adns_state ads, void context, adns_query query_r,
	458	adns_rrtype type, adns_queryflags flags,
	459	int id, adns_status stat) {
	460	adns_query qu;
80917fcc	461
350d37d9	462	qu= allocquery(ads,0,0,0,id,type,flags,context); if (!qu) return errno;
	463	query_fail(ads,qu,stat);
	464	*query_r= qu;
	465	return 0;
	466	}
	467
	468	int adns_submit(adns_state ads,
	469	const char *owner,
	470	adns_rrtype type,
	471	adns_queryflags flags,
	472	void *context,
	473	adns_query *query_r) {
	474	adns_query qu;
	475	adns_status stat;
	476	int ol, id, qml;
	477
	478	id= ads->nextid++;
	479
	480	ol= strlen(owner);
	481	if (ol<=1 \|\| ol>MAXDNAME+1)
	482	return failsubmit(ads,context,query_r,type,flags,id,adns_s_invaliddomain);
	483	if (owner[ol-1]=='.' && owner[ol-2]!='\\') { flags &= ~adns_f_search; ol--; }
	484
	485	stat= mkquery(ads,owner,ol,id,type,flags,&qml);
	486	if (stat) return failsubmit(ads,context,query_r,type,flags,id,stat);
	487
	488	qu= allocquery(ads,owner,ol,qml,id,type,flags,context); if (!qu) return errno;
	489
	490	LIST_LINK_TAIL(ads->input,qu);
	491	autosys(ads);
80917fcc	492
a17d3a1d	493	*query_r= qu;
e8c505a5	494	return 0;
a17d3a1d	495	}