X-Git-Url: http://git.harvie.cz/?p=svn%2FPrometheus-QoS%2F.git;a=blobdiff_plain;f=ipv6subnets.c;fp=ipv6subnets.c;h=ce8f7092370a00fbe5a5a00af4c764f449b8b175;hp=0000000000000000000000000000000000000000;hb=0b9c3c198771800cc6c5fbacfc0272549626bcfd;hpb=f64d54310ae39276c552b80183ae2320789bb4be

diff --git a/ipv6subnets.c b/ipv6subnets.c
new file mode 100644
index 0000000..ce8f709
--- /dev/null
+++ b/ipv6subnets.c
@@ -0,0 +1,98 @@
+#include "cll1-0.6.2.h"
+
+/* ====== iptables indexes are used to reduce complexity to log(N) ===== */
+
+char *very_ugly_ipv6_code(char *inip, int bitmask, int format_as_chainname)
+{
+ int colon=0, n, h;
+ char *ip,*outip,*outptr,*fmt;
+
+ duplicate(inip,ip);
+ /* debug printf("(%s,%d) -> ",ip,bitmask); */
+
+ if(ip && *ip && bitmask>=0 && bitmask<=64)
+ {
+  string(outip,strlen(ip)+10); /* assertion: 10>strlen("_%d_%d") */
+ }
+ else
+ {
+  /* should never exit here */
+  return "undefined";
+ }
+ outptr=outip;
+ while(ip && *ip)
+ {
+  if(*ip==':')
+  {
+   if(colon<(bitmask/16-1))
+   {
+    if(format_as_chainname)
+    {
+     *outptr='_';
+    }
+    else
+    {
+     *outptr=':';
+    }
+    outptr++;
+    colon++;
+   }
+   else
+   {
+    char *cutcolon=strchr(ip+1,':');
+    if(cutcolon)
+    {
+     *cutcolon = '\0';
+    }
+    
+    if(format_as_chainname)
+    {
+     fmt = "_%x_%d";
+    }
+    else
+    {
+     fmt = ":%x";
+    }
+    
+    if(bitmask%16)
+    {
+     sscanf(ip+1, "%x", &h);
+/*    printf("[debug - %s scanned hexa as %x]\n",ip+1,h);*/
+     n = h-h%(1<<(16-bitmask%16));
+    }
+    else
+    {
+     n = 0;
+    }
+
+/*  printf("%d/%d => [_%d_%d]\n",h,bitmask,n,bitmask); */
+    sprintf(outptr,fmt,n,bitmask);
+    if(!format_as_chainname)
+    {
+     strcat(outip,"::");  /* ahem :-) */
+    }
+    /* debug printf("[%s]\n",outip); */
+    return outip;
+   }
+  }
+  else
+  {
+   *outptr=*ip;
+   outptr++;
+  }
+  ip++;
+ }
+ /*should never exit here*/
+ *outptr='\0';
+ return outip;
+}
+
+char *index6_id(char *ip,int bitmask)
+{ 
+ return very_ugly_ipv6_code(ip,bitmask,1);
+}
+
+char *subnet6_id(char *ip,int bitmask)
+{
+ return very_ugly_ipv6_code(ip,bitmask,0);
+}