From: ian <ian>
Date: Wed, 1 Mar 2000 23:50:05 +0000 (+0000)
Subject: +  * Better checking of long domain names and labels in queries.
X-Git-Tag: rel-adns-0-7~10
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=adns.git;a=commitdiff_plain;h=4b2c4f8a37e33604c1aeddafe49b7c33089692a4;ds=sidebyside

+  * Better checking of long domain names and labels in queries.

@@ -2,6 +2,8 @@
+  * Better checking of long domain names and labels in queries.
+  * Unfortunately, answer->owner may be null on error.  Documented.
---

diff --git a/changelog b/changelog
index f41efb6..155d177 100644
--- a/changelog
+++ b/changelog
@@ -2,6 +2,8 @@ adns (0.7) BETA; urgency=medium
 
   * README updated (from www home page).
   * Better reporting of unexpected or weird replies from nameserver.
+  * Better checking of long domain names and labels in queries.
+  * Unfortunately, answer->owner may be null on error.  Documented.
 
  --
 
diff --git a/client/adh-query.c b/client/adh-query.c
index bae71f4..cc5dc12 100644
--- a/client/adh-query.c
+++ b/client/adh-query.c
@@ -89,6 +89,7 @@ void of_ptr(const struct optioninfo *oi, const char *arg) {
   if (!inet_aton(arg,&sa.sin_addr)) usageerr("invalid IP address %s",arg);
 
   prep_query(&qun,&quflags);
+  qun->owner= xstrsave(arg);
   r= adns_submit_reverse(ads,
 			 (struct sockaddr*)&sa,
 			 ov_type == adns_r_none ? adns_r_ptr : ov_type,
@@ -105,6 +106,7 @@ void query_do(const char *domain) {
   int quflags, r;
 
   prep_query(&qun,&quflags);
+  qun->owner= xstrsave(domain);
   r= adns_submit(ads, domain,
 		 ov_type == adns_r_none ? adns_r_addr : ov_type,
 		 quflags,
@@ -145,8 +147,12 @@ static void print_ttl(struct query_node *qun, adns_answer *answer) {
   if (printf("%lu ",ttl) == EOF) outerr();
 }
 
+static const char *owner_show(struct query_node *qun, adns_answer *answer) {
+  return answer->owner ? answer->owner : qun->owner;
+}
+
 static void print_owner_ttl(struct query_node *qun, adns_answer *answer) {
-  if (qun->pqfr.show_owner) print_withspace(answer->owner);
+  if (qun->pqfr.show_owner) print_withspace(owner_show(qun,answer));
   print_ttl(qun,answer);
 }
 
@@ -195,15 +201,15 @@ static void print_dnsfail(adns_status st, struct query_node *qun, adns_answer *a
   }
   assert(ov_format == fmt_simple);
   if (st == adns_s_nxdomain) {
-    r= fprintf(stderr,"%s does not exist\n", answer->owner);
+    r= fprintf(stderr,"%s does not exist\n", owner_show(qun,answer));
   } else {
     ist= adns_rr_info(answer->type, &typename, 0,0,0,0);
     if (st == adns_s_nodata) {
-      r= fprintf(stderr,"%s has no %s record\n", answer->owner, typename);
+      r= fprintf(stderr,"%s has no %s record\n", owner_show(qun,answer), typename);
     } else {
       statusstring= adns_strerror(st);
       r= fprintf(stderr,"Error during DNS %s lookup for %s: %s\n",
-		 typename, answer->owner, statusstring);
+		 typename, owner_show(qun,answer), statusstring);
     }
   }
   if (r == EOF) sysfail("write error message to stderr",errno);
@@ -233,7 +239,7 @@ void query_done(struct query_node *qun, adns_answer *answer) {
     }
   }
   if (qun->pqfr.show_owner) {
-    realowner= answer->cname ? answer->cname : answer->owner;
+    realowner= answer->cname ? answer->cname : owner_show(qun,answer);
     assert(realowner);
   } else {
     realowner= 0;
diff --git a/client/adnshost.h b/client/adnshost.h
index 8b459b3..93a7608 100644
--- a/client/adnshost.h
+++ b/client/adnshost.h
@@ -90,7 +90,7 @@ void opt_do(const struct optioninfo *oip, const char *arg, int invert);
 struct query_node {
   struct query_node *next, *back;
   struct perqueryflags_remember pqfr;
-  char *id;
+  char *id, *owner;
   adns_query qu;
 };
 
diff --git a/src/adns.h b/src/adns.h
index feb9f9d..6643864 100644
--- a/src/adns.h
+++ b/src/adns.h
@@ -284,7 +284,7 @@ typedef struct {
 typedef struct {
   adns_status status;
   char *cname; /* always NULL if query was for CNAME records */
-  char *owner; /* only set if requested in query flags */
+  char *owner; /* only set if requested in query flags, and may be 0 on error anyway */
   adns_rrtype type; /* guaranteed to be same as in query */
   time_t expires; /* expiry time, defined only if _s_ok, nxdomain or nodata. NOT TTL! */
   int nrrs, rrsz; /* nrrs is 0 if an error occurs */
diff --git a/src/general.c b/src/general.c
index 8793762..d5bdcb0 100644
--- a/src/general.c
+++ b/src/general.c
@@ -244,7 +244,7 @@ static const struct sinfo {
 
   SINFO(  querydomainwrong,    "Domain invalid for particular DNS query type"  ),
   SINFO(  querydomaininvalid,  "Domain name is syntactically invalid"          ),
-  SINFO(  querydomaintoolong,  "Domain name is too long"                       ),
+  SINFO(  querydomaintoolong,  "Domain name or component is too long"          ),
 
   SINFO(  nxdomain,            "No such domain"                                ),
   SINFO(  nodata,              "No such data"                                  )
diff --git a/src/transmit.c b/src/transmit.c
index c669af6..b97ffc6 100644
--- a/src/transmit.c
+++ b/src/transmit.c
@@ -77,7 +77,7 @@ static adns_status mkquery_footer(vbuf *vb, adns_rrtype type) {
 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;
+  int ll, c, nbytes;
   byte label[255], *rqp;
   const char *p, *pe;
   adns_status st;
@@ -87,7 +87,7 @@ adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r,
   MKQUERY_START(vb);
 
   p= owner; pe= owner+ol;
-  nlabs= 0;
+  nbytes= 0;
   while (p!=pe) {
     ll= 0;
     while (p!=pe && (c= *p++)!='.') {
@@ -115,7 +115,9 @@ adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r,
       label[ll++]= c;
     }
     if (!ll) return adns_s_querydomaininvalid;
-    if (nlabs++ > 63) return adns_s_querydomaintoolong;
+    if (ll > 63) return adns_s_querydomaintoolong;
+    nbytes+= ll+1;
+    if (nbytes > 254) return adns_s_querydomaintoolong;
     MKQUERY_ADDB(ll);
     memcpy(rqp,label,ll); rqp+= ll;
   }