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-rw-r--r--adns-0.6/src/transmit.c257
1 files changed, 257 insertions, 0 deletions
diff --git a/adns-0.6/src/transmit.c b/adns-0.6/src/transmit.c
new file mode 100644
index 0000000..c669af6
--- /dev/null
+++ b/adns-0.6/src/transmit.c
@@ -0,0 +1,257 @@
+/*
+ * transmit.c
+ * - construct queries
+ * - send queries
+ */
+/*
+ * This file is
+ * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ *
+ * It is part of adns, which is
+ * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ * Copyright (C) 1999 Tony Finch <dot@dotat.at>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <errno.h>
+
+#include <sys/types.h>
+#include <sys/uio.h>
+
+#include "internal.h"
+#include "tvarith.h"
+
+#define MKQUERY_START(vb) (rqp= (vb)->buf+(vb)->used)
+#define MKQUERY_ADDB(b) *rqp++= (b)
+#define MKQUERY_ADDW(w) (MKQUERY_ADDB(((w)>>8)&0x0ff), MKQUERY_ADDB((w)&0x0ff))
+#define MKQUERY_STOP(vb) ((vb)->used= rqp-(vb)->buf)
+
+static adns_status mkquery_header(adns_state ads, vbuf *vb, int *id_r, int qdlen) {
+ int id;
+ byte *rqp;
+
+ if (!adns__vbuf_ensure(vb,DNS_HDRSIZE+qdlen+4)) return adns_s_nomemory;
+
+ vb->used= 0;
+ MKQUERY_START(vb);
+
+ *id_r= id= (ads->nextid++) & 0x0ffff;
+ 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 */
+
+ MKQUERY_STOP(vb);
+
+ return adns_s_ok;
+}
+
+static adns_status mkquery_footer(vbuf *vb, adns_rrtype type) {
+ byte *rqp;
+
+ MKQUERY_START(vb);
+ MKQUERY_ADDW(type & adns__rrt_typemask); /* QTYPE */
+ MKQUERY_ADDW(DNS_CLASS_IN); /* QCLASS=IN */
+ MKQUERY_STOP(vb);
+ assert(vb->used <= vb->avail);
+
+ return adns_s_ok;
+}
+
+adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r,
+ const char *owner, int ol,
+ const typeinfo *typei, adns_queryflags flags) {
+ int ll, c, nlabs;
+ byte label[255], *rqp;
+ const char *p, *pe;
+ adns_status st;
+
+ st= mkquery_header(ads,vb,id_r,ol+2); if (st) return st;
+
+ MKQUERY_START(vb);
+
+ p= owner; pe= owner+ol;
+ nlabs= 0;
+ while (p!=pe) {
+ ll= 0;
+ while (p!=pe && (c= *p++)!='.') {
+ if (c=='\\') {
+ if (!(flags & adns_qf_quoteok_query)) return adns_s_querydomaininvalid;
+ 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_querydomaininvalid;
+ } else {
+ return adns_s_querydomaininvalid;
+ }
+ } else if (!(c= *p++)) {
+ return adns_s_querydomaininvalid;
+ }
+ }
+ if (!(flags & adns_qf_quoteok_query)) {
+ if (c == '-') {
+ if (!ll) return adns_s_querydomaininvalid;
+ } else if (!ctype_alpha(c) && !ctype_digit(c)) {
+ return adns_s_querydomaininvalid;
+ }
+ }
+ if (ll == sizeof(label)) return adns_s_querydomaininvalid;
+ label[ll++]= c;
+ }
+ if (!ll) return adns_s_querydomaininvalid;
+ if (nlabs++ > 63) return adns_s_querydomaintoolong;
+ MKQUERY_ADDB(ll);
+ memcpy(rqp,label,ll); rqp+= ll;
+ }
+ MKQUERY_ADDB(0);
+
+ MKQUERY_STOP(vb);
+
+ st= mkquery_footer(vb,typei->type);
+
+ return adns_s_ok;
+}
+
+adns_status adns__mkquery_frdgram(adns_state ads, vbuf *vb, int *id_r,
+ const byte *qd_dgram, int qd_dglen, int qd_begin,
+ adns_rrtype type, adns_queryflags flags) {
+ byte *rqp;
+ findlabel_state fls;
+ int lablen, labstart;
+ adns_status st;
+
+ st= mkquery_header(ads,vb,id_r,qd_dglen); if (st) return st;
+
+ MKQUERY_START(vb);
+
+ adns__findlabel_start(&fls,ads,-1,0,qd_dgram,qd_dglen,qd_dglen,qd_begin,0);
+ for (;;) {
+ st= adns__findlabel_next(&fls,&lablen,&labstart); assert(!st);
+ if (!lablen) break;
+ assert(lablen<255);
+ MKQUERY_ADDB(lablen);
+ memcpy(rqp,qd_dgram+labstart,lablen);
+ rqp+= lablen;
+ }
+ MKQUERY_ADDB(0);
+
+ MKQUERY_STOP(vb);
+
+ st= mkquery_footer(vb,type);
+
+ return adns_s_ok;
+}
+
+void adns__querysend_tcp(adns_query qu, struct timeval now) {
+ byte length[2];
+ struct iovec iov[2];
+ int wr, r;
+ adns_state ads;
+
+ if (qu->ads->tcpstate != server_ok) return;
+
+ assert(qu->state == query_tcpw);
+
+ length[0]= (qu->query_dglen&0x0ff00U) >>8;
+ length[1]= (qu->query_dglen&0x0ff);
+
+ ads= qu->ads;
+ if (!adns__vbuf_ensure(&ads->tcpsend,ads->tcpsend.used+qu->query_dglen+2)) return;
+
+ qu->retries++;
+
+ /* Reset idle timeout. */
+ ads->tcptimeout.tv_sec= ads->tcptimeout.tv_usec= 0;
+
+ if (ads->tcpsend.used) {
+ wr= 0;
+ } else {
+ iov[0].iov_base= length;
+ iov[0].iov_len= 2;
+ iov[1].iov_base= qu->query_dgram;
+ iov[1].iov_len= qu->query_dglen;
+ adns__sigpipe_protect(qu->ads);
+ wr= writev(qu->ads->tcpsocket,iov,2);
+ adns__sigpipe_unprotect(qu->ads);
+ if (wr < 0) {
+ if (!(errno == EAGAIN || errno == EINTR || errno == ENOSPC ||
+ errno == ENOBUFS || errno == ENOMEM)) {
+ adns__tcp_broken(ads,"write",strerror(errno));
+ return;
+ }
+ wr= 0;
+ }
+ }
+
+ if (wr<2) {
+ r= adns__vbuf_append(&ads->tcpsend,length,2-wr); assert(r);
+ wr= 0;
+ } else {
+ wr-= 2;
+ }
+ if (wr<qu->query_dglen) {
+ r= adns__vbuf_append(&ads->tcpsend,qu->query_dgram+wr,qu->query_dglen-wr); assert(r);
+ }
+}
+
+static void query_usetcp(adns_query qu, struct timeval now) {
+ qu->state= query_tcpw;
+ qu->timeout= now;
+ timevaladd(&qu->timeout,TCPWAITMS);
+ LIST_LINK_TAIL(qu->ads->tcpw,qu);
+ adns__querysend_tcp(qu,now);
+ adns__tcp_tryconnect(qu->ads,now);
+}
+
+void adns__query_send(adns_query qu, struct timeval now) {
+ struct sockaddr_in servaddr;
+ int serv, r;
+ adns_state ads;
+
+ assert(qu->state == query_tosend);
+ if ((qu->flags & adns_qf_usevc) || (qu->query_dglen > DNS_MAXUDP)) {
+ query_usetcp(qu,now);
+ return;
+ }
+
+ if (qu->retries >= UDPMAXRETRIES) {
+ adns__query_fail(qu,adns_s_timeout);
+ return;
+ }
+
+ serv= qu->udpnextserver;
+ memset(&servaddr,0,sizeof(servaddr));
+
+ ads= qu->ads;
+ servaddr.sin_family= AF_INET;
+ servaddr.sin_addr= ads->servers[serv].addr;
+ servaddr.sin_port= htons(DNS_PORT);
+
+ r= sendto(ads->udpsocket,qu->query_dgram,qu->query_dglen,0,
+ (const struct sockaddr*)&servaddr,sizeof(servaddr));
+ if (r<0 && errno == EMSGSIZE) { qu->retries= 0; query_usetcp(qu,now); return; }
+ if (r<0) adns__warn(ads,serv,0,"sendto failed: %s",strerror(errno));
+
+ qu->timeout= now;
+ timevaladd(&qu->timeout,UDPRETRYMS);
+ qu->udpsent |= (1<<serv);
+ qu->udpnextserver= (serv+1)%ads->nservers;
+ qu->retries++;
+ LIST_LINK_TAIL(ads->udpw,qu);
+}
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