11 adns_status
adns__mkquery(adns_state ads
, vbuf
*vb
,
12 const char *owner
, int ol
, int *id_r
,
13 const typeinfo
*typei
, adns_queryflags flags
) {
15 byte label
[255], *rqp
;
18 #define MKQUERY_ADDB(b) *rqp++= (b)
19 #define MKQUERY_ADDW(w) (MKQUERY_ADDB(((w)>>8)&0x0ff), MKQUERY_ADDB((w)&0x0ff))
22 if (!adns__vbuf_ensure(vb
,DNS_HDRSIZE
+strlen(owner
)+1+5))
23 return adns_s_nolocalmem
;
26 *id_r
= id
= (ads
->nextid
++) & 0x0ffff;
29 MKQUERY_ADDB(0x01); /* QR=Q(0), OPCODE=QUERY(0000), !AA, !TC, RD */
30 MKQUERY_ADDB(0x00); /* !RA, Z=000, RCODE=NOERROR(0000) */
31 MKQUERY_ADDW(1); /* QDCOUNT=1 */
32 MKQUERY_ADDW(0); /* ANCOUNT=0 */
33 MKQUERY_ADDW(0); /* NSCOUNT=0 */
34 MKQUERY_ADDW(0); /* ARCOUNT=0 */
35 p
= owner
; pe
= owner
+ol
;
37 if (!*p
) return adns_s_invaliddomain
;
40 while (p
!=pe
&& (c
= *p
++)!='.') {
42 if (!(flags
& adns_qf_anyquote
)) return adns_s_invaliddomain
;
43 if (ctype_digit(p
[0])) {
44 if (ctype_digit(p
[1]) && ctype_digit(p
[2])) {
45 c
= (*p
++ - '0')*100 + (*p
++ - '0')*10 + (*p
++ - '0');
46 if (c
>= 256) return adns_s_invaliddomain
;
48 return adns_s_invaliddomain
;
50 } else if (!(c
= *p
++)) {
51 return adns_s_invaliddomain
;
54 if (!(flags
& adns_qf_anyquote
)) {
55 if (ctype_digit(c
) || c
== '-') {
56 if (!ll
) return adns_s_invaliddomain
;
57 } else if (!ctype_alpha(c
)) {
58 return adns_s_invaliddomain
;
61 if (ll
== sizeof(label
)) return adns_s_invaliddomain
;
64 if (!ll
) return adns_s_invaliddomain
;
65 if (nlabs
++ > 63) return adns_s_invaliddomain
;
67 memcpy(rqp
,label
,ll
); rqp
+= ll
;
71 MKQUERY_ADDW(typei
->type
& adns__rrt_typemask
); /* QTYPE */
72 MKQUERY_ADDW(DNS_CLASS_IN
); /* QCLASS=IN */
74 vb
->used
= rqp
- vb
->buf
;
75 assert(vb
->used
<= vb
->avail
);
80 void adns__query_tcp(adns_state ads
, adns_query qu
, struct timeval now
) {
81 /* Query must be in state tcpwait/timew; it will be moved to a new state
82 * if possible and no further processing can be done on it for now.
83 * (Resulting state is one of tcpwait/timew (if server not connected),
84 * tcpsent/timew, child/childw or done/output.)
86 * adns__tcp_tryconnect should already have been called - _tcp
87 * will only use an existing connection (if there is one), which it
88 * may break. If the conn list lost then the caller is responsible for any
89 * reestablishment and retry.
95 if (ads
->tcpstate
!= server_ok
) return;
97 length
[0]= (qu
->query_dglen
&0x0ff00U
) >>8;
98 length
[1]= (qu
->query_dglen
&0x0ff);
100 if (!adns__vbuf_ensure(&ads
->tcpsend
,ads
->tcpsend
.used
+qu
->query_dglen
+2)) return;
102 timevaladd(&now
,TCPMS
);
104 qu
->state
= query_tcpsent
;
105 LIST_LINK_TAIL(ads
->timew
,qu
);
107 if (ads
->tcpsend
.used
) {
110 iov
[0].iov_base
= length
;
112 iov
[1].iov_base
= qu
->query_dgram
;
113 iov
[1].iov_len
= qu
->query_dglen
;
114 wr
= writev(ads
->tcpsocket
,iov
,2);
116 if (!(errno
== EAGAIN
|| errno
== EINTR
|| errno
== ENOSPC
||
117 errno
== ENOBUFS
|| errno
== ENOMEM
)) {
118 adns__tcp_broken(ads
,"write",strerror(errno
));
126 r
= adns__vbuf_append(&ads
->tcpsend
,length
,2-wr
); assert(r
);
131 if (wr
<qu
->query_dglen
) {
132 r
= adns__vbuf_append(&ads
->tcpsend
,qu
->query_dgram
+wr
,qu
->query_dglen
-wr
); assert(r
);
136 static void query_usetcp(adns_state ads
, adns_query qu
, struct timeval now
) {
137 timevaladd(&now
,TCPMS
);
139 qu
->state
= query_tcpwait
;
140 LIST_LINK_TAIL(ads
->timew
,qu
);
141 adns__query_tcp(ads
,qu
,now
);
142 adns__tcp_tryconnect(ads
,now
);
145 void adns__query_udp(adns_state ads
, adns_query qu
, struct timeval now
) {
146 /* Query must be in state udp/NONE; it will be moved to a new state,
147 * and no further processing can be done on it for now.
148 * (Resulting state is one of udp/timew, tcpwait/timew (if server not connected),
149 * tcpsent/timew, child/childw or done/output.)
151 struct sockaddr_in servaddr
;
154 assert(qu
->state
== query_udp
);
155 if ((qu
->flags
& adns_qf_usevc
) || (qu
->query_dglen
> DNS_MAXUDP
)) {
156 query_usetcp(ads
,qu
,now
);
160 if (qu
->udpretries
>= UDPMAXRETRIES
) {
161 adns__query_fail(ads
,qu
,adns_s_timeout
);
165 serv
= qu
->udpnextserver
;
166 memset(&servaddr
,0,sizeof(servaddr
));
167 servaddr
.sin_family
= AF_INET
;
168 servaddr
.sin_addr
= ads
->servers
[serv
].addr
;
169 servaddr
.sin_port
= htons(DNS_PORT
);
171 r
= sendto(ads
->udpsocket
,qu
->query_dgram
,qu
->query_dglen
,0,&servaddr
,sizeof(servaddr
));
172 if (r
<0 && errno
== EMSGSIZE
) { query_usetcp(ads
,qu
,now
); return; }
173 if (r
<0) adns__warn(ads
,serv
,0,"sendto failed: %s",strerror(errno
));
175 timevaladd(&now
,UDPRETRYMS
);
177 qu
->udpsent
|= (1<<serv
);
178 qu
->udpnextserver
= (serv
+1)%ads
->nservers
;
180 LIST_LINK_TAIL(ads
->timew
,qu
);
183 static void adns__query_done(adns_state ads
, adns_query qu
) {
188 qu
->answer
= ans
= realloc(qu
->answer
,
189 MEM_ROUND(MEM_ROUND(sizeof(*ans
)) +
190 qu
->interim_allocd
));
191 qu
->final_allocspace
= (byte
*)qu
->answer
+ MEM_ROUND(sizeof(*ans
));
193 adns__makefinal_str(qu
,&ans
->cname
);
195 adns__makefinal_block(qu
,&ans
->rrs
.untyped
,ans
->rrsz
*ans
->nrrs
);
196 for (i
=0; i
<ans
->nrrs
; i
++)
197 qu
->typei
->makefinal(ads
,qu
,ans
->rrs
.bytes
+ans
->rrsz
*i
);
200 for (an
= qu
->allocations
; an
; an
= ann
) { ann
= an
->next
; free(an
); }
202 adns__vbuf_free(&qu
->vb
);
205 LIST_LINK_TAIL(ads
->output
,qu
);
208 void adns__reset_cnameonly(adns_state ads
, adns_query qu
) {
209 assert(qu
->final_allocspace
);
212 qu
->interim_allocd
= qu
->answer
->cname ?
MEM_ROUND(strlen(qu
->answer
->cname
)+1) : 0;
215 void adns__query_fail(adns_state ads
, adns_query qu
, adns_status stat
) {
216 adns__reset_cnameonly(ads
,qu
);
217 qu
->answer
->status
= stat
;
218 adns__query_done(ads
,qu
);