release/src/router/dnsmasq/src/dns-protocol.h

   1 /* dnsmasq is Copyright (c) 2000-2013 Simon Kelley
   2
   3    This program is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; version 2 dated June, 1991, or
   6    (at your option) version 3 dated 29 June, 2007.
   7
   8    This program is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11    GNU General Public License for more details.
  12
  13    You should have received a copy of the GNU General Public License
  14    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15 */
  16
  17 #define NAMESERVER_PORT 53
  18 #define TFTP_PORT       69
  19
  20 #define IN6ADDRSZ       16
  21 #define INADDRSZ        4
  22
  23 #define PACKETSZ        512             /* maximum packet size */
  24 #define MAXDNAME        1025            /* maximum presentation domain name */
  25 #define RRFIXEDSZ       10              /* #/bytes of fixed data in r record */
  26 #define MAXLABEL        63              /* maximum length of domain label */
  27
  28 #define NOERROR         0               /* no error */
  29 #define FORMERR         1               /* format error */
  30 #define SERVFAIL        2               /* server failure */
  31 #define NXDOMAIN        3               /* non existent domain */
  32 #define NOTIMP          4               /* not implemented */
  33 #define REFUSED         5               /* query refused */
  34
  35 #define QUERY           0               /* opcode */
  36
  37 #define C_IN            1               /* the arpa internet */
  38 #define C_CHAOS         3               /* for chaos net (MIT) */
  39 #define C_ANY           255             /* wildcard match */
  40
  41 #define T_A             1
  42 #define T_NS            2
  43 #define T_CNAME         5
  44 #define T_SOA           6
  45 #define T_PTR           12
  46 #define T_MX            15
  47 #define T_TXT           16
  48 #define T_SIG           24
  49 #define T_AAAA          28
  50 #define T_SRV           33
  51 #define T_NAPTR         35
  52 #define T_OPT           41
  53 #define T_TKEY          249
  54 #define T_TSIG          250
  55 #define T_AXFR          252
  56 #define T_MAILB         253
  57 #define T_ANY           255
  58
  59 struct dns_header {
  60   u16 id;
  61   u8  hb3,hb4;
  62   u16 qdcount,ancount,nscount,arcount;
  63 };
  64
  65 #define HB3_QR       0x80
  66 #define HB3_OPCODE   0x78
  67 #define HB3_AA       0x04
  68 #define HB3_TC       0x02
  69 #define HB3_RD       0x01
  70
  71 #define HB4_RA       0x80
  72 #define HB4_AD       0x20
  73 #define HB4_CD       0x10
  74 #define HB4_RCODE    0x0f
  75
  76 #define OPCODE(x)          (((x)->hb3 & HB3_OPCODE) >> 3)
  77 #define RCODE(x)           ((x)->hb4 & HB4_RCODE)
  78 #define SET_RCODE(x, code) (x)->hb4 = ((x)->hb4 & ~HB4_RCODE) | code
  79
  80 #define GETSHORT(s, cp) { \
  81         unsigned char *t_cp = (unsigned char *)(cp); \
  82         (s) = ((u16)t_cp[0] << 8) \
  83             | ((u16)t_cp[1]) \
  84             ; \
  85         (cp) += 2; \
  86 }
  87
  88 #define GETLONG(l, cp) { \
  89         unsigned char *t_cp = (unsigned char *)(cp); \
  90         (l) = ((u32)t_cp[0] << 24) \
  91             | ((u32)t_cp[1] << 16) \
  92             | ((u32)t_cp[2] << 8) \
  93             | ((u32)t_cp[3]) \
  94             ; \
  95         (cp) += 4; \
  96 }
  97
  98 #define PUTSHORT(s, cp) { \
  99         u16 t_s = (u16)(s); \
 100         unsigned char *t_cp = (unsigned char *)(cp); \
 101         *t_cp++ = t_s >> 8; \
 102         *t_cp   = t_s; \
 103         (cp) += 2; \
 104 }
 105
 106 #define PUTLONG(l, cp) { \
 107         u32 t_l = (u32)(l); \
 108         unsigned char *t_cp = (unsigned char *)(cp); \
 109         *t_cp++ = t_l >> 24; \
 110         *t_cp++ = t_l >> 16; \
 111         *t_cp++ = t_l >> 8; \
 112         *t_cp   = t_l; \
 113         (cp) += 4; \
 114 }
 115