return 1;
}
-adns_status adns__get_label(const byte *dgram, int dglen, int *max_io,
- int *cbyte_io, int *lablen_r, int *labstart_r,
- int *namelen_io) {
- /* If succeeds, *lablen_r may be set to -1 to indicate truncation/overrun */
- int max, cbyte, lablen, namelen;
+void adns__findlabel_start(findlabel_state *fls,
+ adns_state ads, int serv,
+ const byte *dgram, int dglen, int max,
+ int dmbegin, int *dmend_rlater) {
+ fls->ads= ads;
+ fls->serv= serv;
+ fls->dgram= dgram;
+ fls->dglen= dglen;
+ fls->max= max;
+ fls->cbyte= dmbegin;
+ fls->namelen= 0;
+ fls->dmend_r= dmend_rlater;
+ fls->namelen_r= namelen_rlater;
+}
- max= *max_io;
- cbyte= *cbyte_io;
-
+adns_status adns__findlabel_next(findlabel_state fls,
+ int *lablen_r, int *labstart_r) {
+ int lablen, jumped;
+
+ jumped= 0;
for (;;) {
- if (cbyte+2 > max) goto x_truncated;
- GET_W(cbyte,lablen);
+ fls->cbyte += 2;
+ if (fls->cbyte > fls->dglen) goto x_truncated;
+ if (fls->cbyte > fls->max) goto x_serverfaulty;
+ GET_W(fls->cbyte-2,lablen);
if (!(lablen & 0x0c000)) break;
if ((lablen & 0x0c000) != 0x0c000) return adns_s_unknownreply;
- if (cbyte_io) { *cbyte_io= cbyte; cbyte_io= 0; }
- cbyte= DNS_HDRSIZE+(lablen&0x3fff);
- *max_io= max= dglen;
+ if (jumped++) {
+ adns__diag(ads,serv,"compressed datagram contains loop");
+ return adns_s_serverfaulty;
+ }
+ if (fls->dmend_r) *(fls->dmend_r)= fls->cbyte;
+ fls->cbyte= DNS_HDRSIZE+(lablen&0x3fff);
+ fls->dmend_r= 0; fls->max= fls->dglen+1;
}
- if (labstart_r) *labstart_r= cbyte;
if (lablen) {
- namelen= *namelen_io;
- if (namelen) namelen++;
- namelen+= lablen;
- if (namelen > DNS_MAXDOMAIN) return adns_s_domaintoolong;
- *namelen_io= namelen;
- cbyte+= lablen;
- if (cbyte > max) goto x_truncated;
+ if (fls->namelen) fls->namelen++;
+ fls->namelen+= lablen;
+ if (fls->namelen > DNS_MAXDOMAIN) return adns_s_domaintoolong;
+ fls->cbyte+= lablen;
+ if (fls->cbyte > fls->dglen) goto x_truncated;
+ if (fls->cbyte > fls->max) goto x_serverfaulty;
+ } else {
+ if (fls->dmend_r) *(fls->dmend_r)= fls->cbyte;
+ if (fls->namelen_r) *(fls->namelen_r)= fls->namelen;
}
- if (cbyte_io) *cbyte_io= cbyte;
+ if (labstart_r) *labstart_r= fls->cbyte;
*lablen_r= lablen;
return adns_s_ok;
x_truncated:
*lablen_r= -1;
return adns_s_ok;
+
+ x_serverfaulty:
+ adns__diag(ads,serv,"label in domain runs beyond end of domain");
+ return adns_s_serverfaulty;
}
-adns_status adns__get_domain_perm(adns_state ads, adns_query qu, int serv,
- const byte *dgram, int dglen,
- int *cbyte_io, int max, int *domainstart_r) {
- /* Returns 0 for OK (*domainstart_r >=0) or truncated (*domainstart_r == -1)
- * or any other adns_s_* value.
- */
- int cbyte, sused, lablen, labstart, namelen, i, ch;
+adns_status adns__parse_domain(adns_state ads, int serv, vbuf *vb,
+ const byte *dgram, int dglen,
+ int *cbyte_io, int max) {
+ findlabel_state fls;
+
+ int cbyte, lablen, labstart, namelen, i, ch;
adns_status st;
- /* If we follow a pointer we set cbyte_io to 0 to indicate that
- * we've lost our original starting and ending points; we don't
- * put the end of the pointed-to thing into the original *cbyte_io.
- */
- cbyte= *cbyte_io;
- sused= qu->ans.used;
- namelen= 0;
+ ands__findlabel_start(&fls,ads,serv, dgram,dglen,max, *cbyte_io,cbyte_io);
+ vb->used= 0;
for (;;) {
- st= adns__get_label(dgram,dglen,&max, &cbyte,&lablen,&labstart,&namelen);
+ st= adns__findlabel_next(&fls,&lablen,&labstart);
if (st) return st;
- if (lablen<0) goto x_truncated;
+ if (lablen<0) { vb->used=0; return adns_s_ok; }
if (!lablen) break;
- if (qu->ans.used != sused)
+ if (vb->used)
if (!adns__vbuf_append(&qu->ans,".",1)) return adns_s_nolocalmem;
if (qu->flags & adns_qf_anyquote) {
if (!vbuf__append_quoted1035(&qu->ans,dgram+labstart,lablen))
return adns_s_nolocalmem;
} else {
if (!ctype_alpha(dgram[labstart])) return adns_s_invaliddomain;
- for (i= cbyte+1; i<cbyte+lablen; i++) {
- ch= dgram[cbyte];
+ for (i= labstart+1; i<labstart+lablen; i++) {
+ ch= dgram[i];
if (ch != '-' && !ctype_alpha(ch) && !ctype_digit(ch))
return adns_s_invaliddomain;
}
return adns_s_nolocalmem;
}
}
- if (cbyte_io) *cbyte_io= cbyte;
if (!adns__vbuf_append(&qu->ans,"",1)) return adns_s_nolocalmem;
- *domainstart_r= sused;
return adns_s_ok;
-
- x_truncated:
- *domainstart_r= -1;
- return cbyte_io ? -1 : adns_s_serverfaulty;
}
-adns_status adns__get_domain_temp(adns_state ads, adns_query qu, int serv,
- const byte *dgram, int dglen,
- int *cbyte_io, int max, int *domainstart_r) {
- int sused;
- adns_status st;
-
- sused= qu->ans.used;
- st= adns__get_domain_perm(ads,qu,serv,dgram,dglen,cbyte_io,max,domainstart_r);
- qu->ans.used= sused;
- return st;
-}
-
-adns_status adns__get_rr_temp(adns_state ads, adns_query qu, int serv,
- const byte *dgram, int dglen, int *cbyte_io,
- int *type_r, int *class_r, int *rdlen_r, int *rdstart_r,
- const byte *eo_dgram, int eo_dglen, int eo_cbyte,
- int *eo_matched_r) {
- /* _s_ok can have *type_r == -1 and other output invalid, for truncation
- * type_r and class_r must be !0, other _r may be 0.
- * eo_dgram==0 for no comparison, otherwise all eo_ must be valid.
+adns_status adns__findrr(adns_state ads, int serv,
+ const byte *dgram, int dglen, int *cbyte_io,
+ int *type_r, int *class_r, int *rdlen_r, int *rdstart_r,
+ const byte *eo_dgram, int eo_dglen, int eo_cbyte,
+ int *eo_matched_r) {
+ /* Finds the extent and some of the contents of an RR in a datagram
+ * and does some checks. The datagram is *dgram, length dglen, and
+ * the RR starts at *cbyte_io (which is updated afterwards to point
+ * to the end of the RR).
+ *
+ * The type, class and RRdata length and start are returned iff
+ * the corresponding pointer variables are not null. type_r and
+ * class_r may not be null.
+ *
+ * If the caller thinks they know what the owner of the RR ought to
+ * be they can pass in details in eo_*: this is another (or perhaps
+ * the same datagram), and a pointer to where the putative owner
+ * starts in that datagram. In this case *eo_matched_r will be set
+ * to 1 if the datagram matched or 0 if it did not. Either
+ * both eo_dgram and eo_matched_r must both be non-null, or they
+ * must both be null (in which case eo_dglen and eo_cbyte will be ignored).
+ * The eo datagram and contained owner domain MUST be valid and
+ * untruncated.
+ *
+ * If there is truncation then *type_r will be set to -1 and
+ * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
+ * undefined.
+ *
+ * If an error is returned then *type_r will be undefined too.
*/
- int cbyte, tmp, rdlen, mismatch;
+ findlabel_state fls, eo_fls;
+ int cbyte;
+
+ int tmp, rdlen, mismatch;
int max, lablen, labstart, namelen, ch;
int eo_max, eo_lablen, eo_labstart, eo_namelen, eo_ch;
adns_status st;
cbyte= *cbyte_io;
- mismatch= eo_dgram ? 1 : 0;
- namelen= 0; eo_namelen= 0;
- max= dglen; eo_max= eo_dglen;
+ ands__findlabel_start(&fls,ads,serv, dgram,dglen,dglen,cbyte,&cbyte);
+ if (eo_dgram) {
+ ands__findlabel_start(&eo_fls,ads,serv, eo_dgram,eo_dglen,eo_dglen,eo_cbyte,0);
+ mismatch= 0;
+ } else {
+ mismatch= 1;
+ }
+
for (;;) {
- st= adns__get_label(dgram,dglen,&max,
- &cbyte,&lablen,&labstart,&namelen);
+ st= adns__findlabel_next(&fls,&lablen,&labstart);
if (st) return st;
if (lablen<0) goto x_truncated;
if (!mismatch) {
- st= adns__get_label(eo_dgram,eo_dglen,&eo_max,
- &eo_cbyte,&eo_lablen,&eo_labstart,&eo_namelen);
- if (st) return st;
- assert(eo_lablen>=0);
+ st= adns__findlabel_next(&eo_fls,&eo_lablen,&eo_labstart);
+ assert(!st); assert(eo_lablen>=0);
if (lablen != eo_lablen) mismatch= 1;
while (!mismatch && lablen-- > 0) {
ch= dgram[labstart++]; if (ctype_alpha(ch)) ch &= ~32;
~ianmdlvl / adns.git / blobdiff