ndb/dnsdebug: handle .ip6.arpa names

diff --git a/sys/src/cmd/ndb/dnsdebug.c b/sys/src/cmd/ndb/dnsdebug.c
index b2f3cebf272a544157082ecedc328d6d2431c12b..01377598a95365614e331ba4b39969d71a761962 100644 (file)
--- a/sys/src/cmd/ndb/dnsdebug.c
+++ b/sys/src/cmd/ndb/dnsdebug.c
@@ -121,6 +121,32 @@ longtime(long t)
        return x;
 }
 
+/*
+ *  convert address into a reverse lookup address
+ */
+static void
+mkptrname(char *ip, char *rip, int rlen)
+{
+       uchar a[IPaddrlen];
+       char *p, *e;
+       int i;
+
+       if(cistrstr(ip, "in-addr.arpa") || cistrstr(ip, "ip6.arpa") || parseip(a, ip) == -1)
+               snprint(rip, rlen, "%s", ip);
+       else if(isv4(a))
+               snprint(rip, rlen, "%ud.%ud.%ud.%ud.in-addr.arpa",
+                       a[15], a[14], a[13], a[12]);
+       else{
+               p = rip;
+               e = rip + rlen;
+               for(i = 15; i >= 0; i--){
+                       p = seprint(p, e, "%ux.", a[i]&0xf);
+                       p = seprint(p, e, "%ux.", a[i]>>4);
+               }
+               seprint(p, e, "ip6.arpa");
+       }
+}
+
 int
 prettyrrfmt(Fmt *f)
 {
@@ -372,7 +398,6 @@ void
 doquery(char *name, char *tstr)
 {
        int len, type, rooted;
-       char *p, *np;
        char buf[1024];
        RR *rr, *rp;
        Request req;
@@ -387,6 +412,13 @@ doquery(char *name, char *tstr)
                else
                        tstr = "ip";
 
+       /* look it up */
+       type = rrtype(tstr);
+       if(type < 0){
+               print("!unknown type %s\n", tstr);
+               return;
+       }
+
        /* if name end in '.', remove it */
        len = strlen(name);
        if(len > 0 && name[len-1] == '.'){
@@ -396,34 +428,10 @@ doquery(char *name, char *tstr)
                rooted = 0;
 
        /* inverse queries may need to be permuted */
-       strncpy(buf, name, sizeof buf);
-       if(strcmp("ptr", tstr) == 0 && cistrstr(name, ".arpa") == nil){
-               /* TODO: reversing v6 addrs is harder */
-               for(p = name; *p; p++)
-                       ;
-               *p = '.';
-               np = buf;
-               len = 0;
-               while(p >= name){
-                       len++;
-                       p--;
-                       if(*p == '.'){
-                               memmove(np, p+1, len);
-                               np += len;
-                               len = 0;
-                       }
-               }
-               memmove(np, p+1, len);
-               np += len;
-               strcpy(np, "in-addr.arpa");     /* TODO: ip6.arpa for v6 */
-       }
-
-       /* look it up */
-       type = rrtype(tstr);
-       if(type < 0){
-               print("!unknown type %s\n", tstr);
-               return;
-       }
+       if(type == Tptr)
+               mkptrname(name, buf, sizeof buf);
+       else
+               strncpy(buf, name, sizeof buf);
 
        memset(&req, 0, sizeof req);
        getactivity(&req, 0);