#include <arpa/inet.h>
#include "adns-internal.h"
-
-#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_PART(list,node) LIST_LINK_TAIL(list,node,)
-
-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->tosend.head= ads->tosend.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;
- qu->id= -1;
- LIST_LINK_TAIL(ads->output,qu);
-}
-
-int adns_finish(adns_state ads) {
- abort(); /* FIXME */
-}
-
-static void autosys(adns_state ads, struct timeval now) {
- 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 void inter_maxto(struct timeval **tv_io, struct timeval *tvbuf,
- struct timeval maxto) {
- struct timeval rbuf;
-
- rbuf= *tv_io;
- if (!rbuf) { *tvbuf= maxto; *tv_io= tvbuf; return; }
- if (timercmp(rbuf,&maxto,>)) *rbuf= maxto;
-}
-
-static void inter_maxtoabs(struct timeval **tv_io, struct timeval *tvbuf,
- struct timeval now, struct timeval maxtime) {
- ldiv_t dr;
-
- maxtime.tv_sec -= (now.tv_sec-1);
- maxtime.tv_usec += (1000-now.tv_usec);
- dr= ldiv(maxtime.tv_usec,1000);
- maxtime.tv_sec += dr.quot;
- maxtime.tv_usec -= dr.rem;
- inter_maxto(tv_io,tvbuf,maxtime);
-}
-
-static void localresourcerr(struct timeval **tv_io, struct timeval *tvbuf,
- const char *syscall) {
- struct timeval tvto_lr;
-
- diag(ads,"local system resources scarce (during %s): %s",syscall,strerror(errno));
- timerclear(&tvto_lr); timevaladd(&tvto_lr,LOCALRESOURCEMS);
- inter_maxto(tv_io, tvbuf, tvto_lr);
- return;
-}
-
-static inline void timevaladd(struct timeval *tv_io, long ms) {
- struct timeval tmp;
- assert(ms>=0);
- tmp= *tv_io;
- tmp.tv_usec += (ms%1000)*1000;
- tmp.tv_sec += ms/1000;
- if (tmp.tv_usec >= 1000) { tmp.tv_sec++; tmp.tv_usec -= 1000; }
- *tv_io= tmp;
-}
-
-void adns_interest(adns_state ads, int *maxfd,
- fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
- struct timeval **tv_io, struct timeval *tvbuf) {
- struct timeval now;
- adns_query qu;
- int r;
-
- r= gettimeofday(&now,0);
- if (r) { localresourcerr(tv_io,tvbuf,"gettimeofday"); return; }
-
- for (qu= ads->timew; qu; qu= nqu) {
- nqu= qu->next;
- if (timercmp(&now,qu->timeout,>)) {
- DLIST_UNLINK(ads->timew,qu);
- if (qu->nextudpserver == -1) {
- query_fail(ads,qu,adns_s_notresponding);
- } else {
- DLIST_LINKTAIL(ads->tosend,qu);
- }
- } else {
- inter_maxtoabs(tv_io,tvbuf,now,qu->timeout);
- }
- }
-
- for (qu= ads->tosend; qu; qu= nqu) {
- nqu= qu->next;
- quproc_tosend(ads,qu,now);
- }
-
- for (qu= ads->timew; qu; qu= qu->next) {
- if (qu->sentudp) {
- inter_addfd(maxfd,readfds,ads->udpsocket);
- break;
- }
- }
- switch (ads->tcpstate) {
- case server_disc:
- break;
- case server_connecting:
- inter_addfd(maxfd,readfds,ads->tcpsocket);
- inter_addfd(maxfd,writefds,ads->tcpsocket);
- inter_addfd(maxfd,exceptfds,ads->tcpsocket);
- break;
- case server_connected:
- inter_addfd(maxfd,readfds,ads->tcpsocket);
- inter_addfd(maxfd,exceptfds,ads->tcpsocket);
- if (ads->opbufused) inter_addfd(maxfd,writefds,ads->tcpsocket);
- default:
- abort();
- }
-
-}
-
-static int internal_check(adns_state ads,
- adns_query *query_io,
- adns_answer **answer,
- void **context_r) {
- adns_query qu;
-
- qu= *query_io;
- if (!qu) {
- if (!ads->output.head) return EWOULDBLOCK;
- qu= ads->output.head;
- } else {
- if (qu->id>=0) return EWOULDBLOCK;
- }
- LIST_UNLINK(ads->output,qu);
- *answer= qu->answer;
- if (context_r) *context_r= qu->context;
- free(qu);
- return 0;
-}
-
-int adns_wait(adns_state ads,
- adns_query *query_io,
- adns_answer **answer_r,
- 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_r,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_r,
- void **context_r) {
- autosys(ads);
- return internal_check(ads,query_io,answer_r,context_r);
-}
-
-int adns_synchronous(adns_state ads,
- const char *owner,
- adns_rrtype type,
- adns_queryflags flags,
- adns_answer **answer_r) {
- 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_r,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= 0;
- qu->children.head= qu->children.tail= 0;
- qu->siblings.next= qu->siblings.back= 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;
-}
-
-static void quproc_tosend(adns_state ads, adns_query qu, struct timeval now) {
- /* Query must be on the `tosend' queue, and guarantees to remove it. */
- struct sockaddr_in servaddr;
- int serv;
-
- if (qu->nextudpserver != -1) {
- if (qu->udpretries >= UDPMAXRETRIES) {
- DLIST_UNLINK(ads->tosend,qu);
- query_fail(ads,qu,adns_s_notresponding);
- return;
- }
- serv= qu->nextudpserver;
- memset(&servaddr,0,sizeof(servaddr));
- servaddr.sin_family= AF_INET;
- servaddr.sin_addr= ads->servers[serv].addr;
- servaddr.sin_port= htons(53);
- r= sendto(ads->udpsocket,qu->querymsg,qu->querylen,0,&servaddr,sizeof(servaddr));
- if (r<0 && errno == EMSGSIZE) {
- qu->nextudpserver= -1;
- } else {
- if (r<0) {
- diag("sendto %s failed: %s",inet_ntoa(servaddr.sin_addr),strerror(errno));
- }
- DLIST_UNLINK(ads->tosend,qu);
- timevaladd(&now,UDPRETRYMS);
- qu->timeout= now;
- qu->sentudp |= (1<<serv);
- qu->nextudpserver= (serv+1)%ads->nservers;
- qu->udpretries++;
- DLIST_LINKTAIL(ads->timew,qu);
- return;
- }
- }
-
- for (;;) {
- serv= tcpserver_get(ads);
- if (serv<0) { r=0; break; }
- if (ads->opbufused) { r=0; break; }
- r= write(ads->tcpsocket,qu->querymsg,qu->querylen);
- if (r >= 0) break;
- if (errno == EAGAIN || errno == EINTR || errno == ENOSPC ||
- errno == ENOBUFS || errno == ENOMEM) {
- r= 0; break;
- }
- tcpserver_broken(serv);
- }
- if (r < qu->querylen) {
- newopbufused= qu->opbufused + (qu->querylen-r);
- if (newopbufused > ads->opbufavail) {
- newopbufavail= ads->newopbufused<<1;
- newopbuf= realloc(newopbufavail);
- if (!newopbuf) {
- DLIST_UNLINK(ads->tosend,qu);
- query_fail(ads,qu,adns_s_nolocalmem);
- return;
- }
- ads->opbuf= newopbuf;
- ads->opbufavail= newopbufavail;
- }
- memcpy(ads->opbuf+ads->opbufused,qu->querymsg+r,qu->querylen-r);
- ads->opbufused= newopbufused;
- }
- DLIST_UNLINK(ads->tosend,qu);
- timevaladd(&now,TCPMS);
- qu->timeout= now;
- qu->senttcp |= (1<<qu->nextserver);
- DLIST_LINKTAIL(ads->timew,qu);
-}
-
-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;
- if (qu->flags & adns_f_usevc) qu->udpretries= -1;
- LIST_LINK_TAIL(ads->tosend,qu);
-
- r= gettimeofday(&now,0); if (r) return;
- quproc_tosend(ads,qu,now);
- autosys(ads,now);
-
- *query_r= qu;
- return 0;
-}
~mdw / adns / blobdiff