10 #include <arpa/nameser.h>
11 #include <sys/socket.h>
12 #include <netinet/in.h>
13 #include <arpa/inet.h>
15 #include "adns-internal.h"
17 #define LIST_UNLINK(list,node) \
19 if ((node)->back) (node)->back->next= (node)->next; \
20 else (list).head= (node)->next; \
21 if ((node)->next) (node)->next->back= (node)->back; \
22 else (list).tail= (node)->back; \
25 #define LIST_LINK_TAIL(list,node) \
28 (node)->next= (list).tail; \
29 if ((list).tail) (list).tail->back= (node); else (list).head= (node); \
30 (list).tail= (node); \
33 static void vdebug(adns_state ads, const char *fmt, va_list al) {
34 if (!(ads->iflags & adns_if_debug)) return;
35 fputs("adns debug: ",stderr);
36 vfprintf(stderr,fmt,al);
40 static void debug(adns_state ads, const char *fmt, ...) {
48 static void vdiag(adns_state ads, const char *fmt, va_list al) {
49 if (ads->iflags & adns_if_noerrprint) return;
50 fputs("adns: ",stderr);
51 vfprintf(stderr,fmt,al);
55 static void diag(adns_state ads, const char *fmt, ...) {
63 static void addserver(adns_state ads, struct in_addr addr) {
66 for (i=0; i<ads->nservers; i++) {
67 if (ads->servers[i].addr.s_addr == addr.s_addr) {
68 debug(ads,"duplicate nameserver %s ignored",inet_ntoa(addr));
73 if (ads->nservers>=MAXSERVERS) {
74 diag(ads,"too many nameservers, ignoring %s",inet_ntoa(addr));
78 ads->servers[ads->nservers].addr= addr;
79 ads->servers[ads->nservers].tcpsocket= -1;
83 static void configparseerr(adns_state ads, const char *fn, int lno,
84 const char *fmt, ...) {
87 if (ads->iflags & adns_if_noerrprint) return;
88 if (lno==-1) fprintf(stderr,"adns: %s: ",fn);
89 else fprintf(stderr,"adns: %s:%d: ",fn,lno);
91 vfprintf(stderr,fmt,al);
96 static void ccf_nameserver(adns_state ads, const char *fn, int lno, const char *buf) {
99 if (!inet_aton(buf,&ia)) {
100 configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
103 debug(ads,"using nameserver %s",inet_ntoa(ia));
107 static void ccf_search(adns_state ads, const char *fn, int lno, const char *buf) {
109 diag(ads,"warning - `search' ignored FIXME");
112 static void ccf_sortlist(adns_state ads, const char *fn, int lno, const char *buf) {
113 diag(ads,"warning - `sortlist' ignored FIXME");
116 static void ccf_options(adns_state ads, const char *fn, int lno, const char *buf) {
118 diag(ads,"warning - `options' ignored FIXME");
121 static void ccf_clearnss(adns_state ads, const char *fn, int lno, const char *buf) {
125 static const struct configcommandinfo {
127 void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
128 } configcommandinfos[]= {
129 { "nameserver", ccf_nameserver },
130 { "domain", ccf_search },
131 { "search", ccf_search },
132 { "sortlist", ccf_sortlist },
133 { "options", ccf_options },
134 { "clearnameservers", ccf_clearnss },
138 static int whitespace(int c) {
139 return c==' ' || c=='\n' || c=='\t';
142 static void readconfig(adns_state ads, const char *filename) {
143 char linebuf[2000], *p, *q;
146 const struct configcommandinfo *ccip;
148 file= fopen(filename,"r");
150 if (errno == ENOENT) {
151 debug(ads,"configuration file `%s' does not exist",filename);
154 diag(ads,"cannot open configuration file `%s': %s",filename,strerror(errno));
158 for (lno=1; fgets(linebuf,sizeof(linebuf),file); lno++) {
161 if (linebuf[l-1] != '\n' && !feof(file)) {
162 diag(ads,"%s:%d: line too long",filename,lno);
163 while ((c= getc(file)) != EOF && c != '\n') { }
167 while (l>0 && whitespace(linebuf[l-1])) l--;
170 while (whitespace(*p)) p++;
171 if (*p == '#' || *p == '\n') continue;
173 while (*q && !whitespace(*q)) q++;
174 for (ccip=configcommandinfos;
175 ccip->name && strncmp(ccip->name,p,q-p);
178 diag(ads,"%s:%d: unknown configuration directive `%.*s'",filename,lno,q-p,p);
181 while (whitespace(*q)) q++;
182 ccip->fn(ads,filename,lno,q);
185 diag(ads,"%s:%d: read error: %s",filename,lno,strerror(errno));
190 static const char *instrum_getenv(adns_state ads, const char *envvar) {
193 value= getenv(envvar);
194 if (!value) debug(ads,"environment variable %s not set",envvar);
195 else debug(ads,"environment variable %s set to `%s'",envvar,value);
199 static void readconfigenv(adns_state ads, const char *envvar) {
200 const char *filename;
202 if (ads->iflags & adns_if_noenv) {
203 debug(ads,"not checking environment variable `%s'",envvar);
206 filename= instrum_getenv(ads,envvar);
207 if (filename) readconfig(ads,filename);
210 int adns_init(adns_state *ads_r, adns_initflags flags) {
212 const char *res_options, *adns_res_options;
214 ads= malloc(sizeof(*ads)); if (!ads) return errno;
215 ads->input.head= ads->input.tail= 0;
216 ads->timew.head= ads->timew.tail= 0;
217 ads->childw.head= ads->childw.tail= 0;
218 ads->output.head= ads->output.tail= 0;
222 ads->tcpbufavail= ads->tcpbufused= ads->tcpbufdone= 0;
228 res_options= instrum_getenv(ads,"RES_OPTIONS");
229 adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
230 ccf_options(ads,"RES_OPTIONS",-1,res_options);
231 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
233 readconfig(ads,"/etc/resolv.conf");
234 readconfigenv(ads,"RES_CONF");
235 readconfigenv(ads,"ADNS_RES_CONF");
237 ccf_options(ads,"RES_OPTIONS",-1,res_options);
238 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
240 ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
241 ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
243 if (!ads->nservers) {
245 if (ads->iflags & adns_if_debug)
246 fprintf(stderr,"adns: no nameservers, using localhost\n");
247 ia.s_addr= INADDR_LOOPBACK;
255 static void query_fail(adns_state ads, adns_query qu, adns_status stat) {
259 if (!ans) ans= malloc(sizeof(*qu->answer));
267 LIST_LINK_TAIL(ads->input,qu);
270 void adns_interest(adns_state ads, int *maxfd,
271 fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
272 struct timeval **tv_io, struct timeval *tvbuf) {
276 static void autosys(adns_state ads) {
277 if (ads->iflags & adns_if_noautosys) return;
278 adns_callback(ads,-1,0,0,0);
281 void adns_cancel(adns_state ads, adns_query query) {
285 int adns_callback(adns_state ads, int maxfd,
286 const fd_set *readfds, const fd_set *writefds,
287 const fd_set *exceptfds) {
291 static int internal_check(adns_state ads,
292 adns_query *query_io,
298 int adns_wait(adns_state ads,
299 adns_query *query_io,
302 int r, maxfd, rsel, rcb;
303 fd_set readfds, writefds, exceptfds;
304 struct timeval tvbuf, *tvp;
307 r= internal_check(ads,query_io,answer,context_r);
308 if (r && r != EWOULDBLOCK) return r;
309 FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds);
311 adns_interest(ads,&maxfd,&readfds,&writefds,&exceptfds,&tvp,&tvbuf);
312 rsel= select(maxfd,&readfds,&writefds,&exceptfds,tvp);
313 if (rsel==-1) return r;
314 rcb= adns_callback(ads,maxfd,&readfds,&writefds,&exceptfds);
319 int adns_check(adns_state ads,
320 adns_query *query_io,
324 return internal_check(ads,query_io,answer,context_r);
327 int adns_synchronous(adns_state ads,
331 adns_answer *answer) {
335 r= adns_submit(ads,owner,type,flags,0,&qu);
338 r= adns_wait(ads,&qu,answer,0);
339 if (r) adns_cancel(ads,qu);
343 int adns_submit(adns_state ads,
348 adns_query *query_r) {
355 if (ol>MAXDNAME+1) { stat= adns_s_invaliddomain; ol= 0; }
356 if (ol>0 && owner[ol-1]=='.') { flags &= ~adns_f_search; ol--; }
357 qu= malloc(sizeof(*qu)+ol+1); if (!qu) return errno;
358 qu->next= qu->back= qu->parent= qu->child= 0;
362 qu->context= context;
365 memcpy(qu->owner,owner,ol); qu->owner[ol]= 0;
367 query_fail(ads,qu,stat);
369 LIST_LINK_TAIL(ads->input,qu);