lib/rfc2671.c

   1 /*
   2  * Copyright (C) 1996-2015 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #include "squid.h"
  10 #include "rfc1035.h"
  11 #include "rfc2671.h"
  12
  13 int
  14 rfc2671RROptPack(char *buf, size_t sz, ssize_t edns_sz)
  15 {
  16     // set the OPT record correctly. base it on a macro size of the Squid DNS read buffer
  17     static rfc1035_rr opt;
  18
  19     // EDNS OPT record says only what our DNS buffer size is so far.
  20     snprintf(opt.name, RFC1035_MAXHOSTNAMESZ, ".");
  21     opt.type = RFC1035_TYPE_OPT;
  22     opt._class = min(edns_sz, (ssize_t)SQUID_UDP_SO_RCVBUF-1);
  23     opt.ttl = 0; // relevant?
  24     opt.rdata = NULL;
  25     opt.rdlength = 0;
  26
  27     return rfc1035RRPack(buf, sz, &opt);
  28 }
  29