12 #include <arpa/nameser.h>
13 #include <sys/socket.h>
14 #include <netinet/in.h>
15 #include <arpa/inet.h>
17 #include "adns-internal.h"
19 #define LIST_UNLINK(list,node) \
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; \
27 #define LIST_LINK_TAIL(list,node) \
30 (node)->next= (list).tail; \
31 if ((list).tail) (list).tail->back= (node); else (list).head= (node); \
32 (list).tail= (node); \
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);
42 static void debug(adns_state ads, const char *fmt, ...) {
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);
57 static void diag(adns_state ads, const char *fmt, ...) {
65 static void addserver(adns_state ads, struct in_addr addr) {
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));
76 if (ads->nservers>=MAXSERVERS) {
77 diag(ads,"too many nameservers, ignoring %s",inet_ntoa(addr));
81 ss= ads->servers+ads->nservers;
83 ss->state= server_disc;
84 ss->connw.head= ss->connw.tail= 0;
88 static void configparseerr(adns_state ads, const char *fn, int lno,
89 const char *fmt, ...) {
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);
96 vfprintf(stderr,fmt,al);
101 static void ccf_nameserver(adns_state ads, const char *fn, int lno, const char *buf) {
104 if (!inet_aton(buf,&ia)) {
105 configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
108 debug(ads,"using nameserver %s",inet_ntoa(ia));
112 static void ccf_search(adns_state ads, const char *fn, int lno, const char *buf) {
114 diag(ads,"warning - `search' ignored FIXME");
117 static void ccf_sortlist(adns_state ads, const char *fn, int lno, const char *buf) {
118 diag(ads,"warning - `sortlist' ignored FIXME");
121 static void ccf_options(adns_state ads, const char *fn, int lno, const char *buf) {
123 diag(ads,"warning - `options' ignored FIXME");
126 static void ccf_clearnss(adns_state ads, const char *fn, int lno, const char *buf) {
130 static const struct configcommandinfo {
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 },
143 static int whitespace(int c) {
144 return c==' ' || c=='\n' || c=='\t';
147 static void readconfig(adns_state ads, const char *filename) {
148 char linebuf[2000], *p, *q;
151 const struct configcommandinfo *ccip;
153 file= fopen(filename,"r");
155 if (errno == ENOENT) {
156 debug(ads,"configuration file `%s' does not exist",filename);
159 diag(ads,"cannot open configuration file `%s': %s",filename,strerror(errno));
163 for (lno=1; fgets(linebuf,sizeof(linebuf),file); lno++) {
166 if (linebuf[l-1] != '\n' && !feof(file)) {
167 diag(ads,"%s:%d: line too long",filename,lno);
168 while ((c= getc(file)) != EOF && c != '\n') { }
172 while (l>0 && whitespace(linebuf[l-1])) l--;
175 while (whitespace(*p)) p++;
176 if (*p == '#' || *p == '\n') continue;
178 while (*q && !whitespace(*q)) q++;
179 for (ccip=configcommandinfos;
180 ccip->name && strncmp(ccip->name,p,q-p);
183 diag(ads,"%s:%d: unknown configuration directive `%.*s'",filename,lno,q-p,p);
186 while (whitespace(*q)) q++;
187 ccip->fn(ads,filename,lno,q);
190 diag(ads,"%s:%d: read error: %s",filename,lno,strerror(errno));
195 static const char *instrum_getenv(adns_state ads, const char *envvar) {
198 value= getenv(envvar);
199 if (!value) debug(ads,"environment variable %s not set",envvar);
200 else debug(ads,"environment variable %s set to `%s'",envvar,value);
204 static void readconfigenv(adns_state ads, const char *envvar) {
205 const char *filename;
207 if (ads->iflags & adns_if_noenv) {
208 debug(ads,"not checking environment variable `%s'",envvar);
211 filename= instrum_getenv(ads,envvar);
212 if (filename) readconfig(ads,filename);
215 int adns_init(adns_state *ads_r, adns_initflags flags) {
217 const char *res_options, *adns_res_options;
218 struct protoent *proto;
219 struct sockaddr_in udpaddr;
222 ads= malloc(sizeof(*ads)); if (!ads) return errno;
223 ads->input.head= ads->input.tail= 0;
224 ads->timew.head= ads->timew.tail= 0;
225 ads->childw.head= ads->childw.tail= 0;
226 ads->output.head= ads->output.tail= 0;
231 ads->tcpbufavail= ads->tcpbufused= ads->tcpbufdone= 0;
237 res_options= instrum_getenv(ads,"RES_OPTIONS");
238 adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
239 ccf_options(ads,"RES_OPTIONS",-1,res_options);
240 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
242 readconfig(ads,"/etc/resolv.conf");
243 readconfigenv(ads,"RES_CONF");
244 readconfigenv(ads,"ADNS_RES_CONF");
246 ccf_options(ads,"RES_OPTIONS",-1,res_options);
247 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
249 ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
250 ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
252 if (!ads->nservers) {
254 if (ads->iflags & adns_if_debug)
255 fprintf(stderr,"adns: no nameservers, using localhost\n");
256 ia.s_addr= INADDR_LOOPBACK;
260 proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
261 ads->udpsocket= socket(AF_INET,SOCK_DGRAM,proto->p_proto);
262 if (!ads->udpsocket) { r= errno; goto x_closeudp; }
264 memset(&udpaddr,0,sizeof(udpaddr));
265 udpaddr.sin_family= AF_INET;
266 udpaddr.sin_addr.s_addr= INADDR_ANY;
268 r= bind(ads->udpsocket,&udpaddr,sizeof(udpaddr));
269 if (r) { r= errno; goto x_closeudp; }
271 udpaddrlen= sizeof(udpaddr);
272 r= getsockname(ads->udpsocket,&udpaddr,&udpaddrlen);
273 if (r) { r= errno; goto x_closeudp; }
274 if (udpaddr.sin_family != AF_INET) {
275 diag(ads,"network API error: UDP socket not AF_INET but %lu",
276 (unsigned long)udpaddr.sin_family);
277 r= EPROTOTYPE; goto x_closeudp;
279 debug(ads,"UDP socket is %s:%u",inet_ntoa(udpaddr.sin_addr),ntohs(udpaddr.sin_port));
285 close(ads->udpsocket);
291 static void query_fail(adns_state ads, adns_query qu, adns_status stat) {
295 if (!ans) ans= malloc(sizeof(*qu->answer));
303 LIST_LINK_TAIL(ads->input,qu);
306 int adns_finish(adns_state ads) {
310 void adns_interest(adns_state ads, int *maxfd,
311 fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
312 struct timeval **tv_io, struct timeval *tvbuf) {
316 static void autosys(adns_state ads) {
317 if (ads->iflags & adns_if_noautosys) return;
318 adns_callback(ads,-1,0,0,0);
321 void adns_cancel(adns_state ads, adns_query query) {
325 int adns_callback(adns_state ads, int maxfd,
326 const fd_set *readfds, const fd_set *writefds,
327 const fd_set *exceptfds) {
331 static int internal_check(adns_state ads,
332 adns_query *query_io,
338 int adns_wait(adns_state ads,
339 adns_query *query_io,
342 int r, maxfd, rsel, rcb;
343 fd_set readfds, writefds, exceptfds;
344 struct timeval tvbuf, *tvp;
347 r= internal_check(ads,query_io,answer,context_r);
348 if (r && r != EWOULDBLOCK) return r;
349 FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds);
351 adns_interest(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf);
352 rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp);
353 if (rsel==-1) return r;
354 rcb= adns_callback(ads,maxfd,&readfds,&writefds,&exceptfds);
359 int adns_check(adns_state ads,
360 adns_query *query_io,
364 return internal_check(ads,query_io,answer,context_r);
367 int adns_synchronous(adns_state ads,
370 adns_queryflags flags,
371 adns_answer *answer) {
375 r= adns_submit(ads,owner,type,flags,0,&qu);
379 r= adns_wait(ads,&qu,answer,0);
381 if (r) adns_cancel(ads,qu);
385 static int mkquery(adns_state ads,
391 int adns_submit(adns_state ads,
394 adns_queryflags flags,
396 adns_query *query_r) {
403 if (ol>MAXDNAME+1) { stat= adns_s_invaliddomain; ol= 0; }
404 if (ol>0 && owner[ol-1]=='.') { flags &= ~adns_f_search; ol--; }
405 qu= malloc(sizeof(*qu)+ol+1); if (!qu) return errno;
406 qu->next= qu->back= qu->parent= qu->child= 0;
407 qu->id= ads->nextid++;
411 qu->context= context;
413 qu->sentudp= qu->senttcp= 0;
415 memcpy(qu->owner,owner,ol); qu->owner[ol]= 0;
418 mkquery(ads,owner,type);
421 query_fail(ads,qu,stat);
423 LIST_LINK_TAIL(ads->input,qu);