dns.h

00001 /**
00002  * @file
00003  * DNS - host name to IP address resolver.
00004  */
00005 
00006 /*
00007  * Port to lwIP from uIP
00008  * by Jim Pettinato April 2007
00009  *
00010  * security fixes and more by Simon Goldschmidt
00011  *
00012  * uIP version Copyright (c) 2002-2003, Adam Dunkels.
00013  * All rights reserved.
00014  *
00015  * Redistribution and use in source and binary forms, with or without
00016  * modification, are permitted provided that the following conditions
00017  * are met:
00018  * 1. Redistributions of source code must retain the above copyright
00019  *    notice, this list of conditions and the following disclaimer.
00020  * 2. Redistributions in binary form must reproduce the above copyright
00021  *    notice, this list of conditions and the following disclaimer in the
00022  *    documentation and/or other materials provided with the distribution.
00023  * 3. The name of the author may not be used to endorse or promote
00024  *    products derived from this software without specific prior
00025  *    written permission.
00026  *
00027  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
00028  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
00029  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
00030  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
00031  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
00032  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
00033  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00034  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
00035  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
00036  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
00037  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00038  */
00039 
00040 #ifndef LWIP_HDR_PROT_DNS_H
00041 #define LWIP_HDR_PROT_DNS_H
00042 
00043 #include "lwip/arch.h"
00044 
00045 #ifdef __cplusplus
00046 extern "C" {
00047 #endif
00048 
00049 /** DNS server port address */
00050 #ifndef DNS_SERVER_PORT
00051 #define DNS_SERVER_PORT           53
00052 #endif
00053 
00054 /* DNS field TYPE used for "Resource Records" */
00055 #define DNS_RRTYPE_A              1     /* a host address */
00056 #define DNS_RRTYPE_NS             2     /* an authoritative name server */
00057 #define DNS_RRTYPE_MD             3     /* a mail destination (Obsolete - use MX) */
00058 #define DNS_RRTYPE_MF             4     /* a mail forwarder (Obsolete - use MX) */
00059 #define DNS_RRTYPE_CNAME          5     /* the canonical name for an alias */
00060 #define DNS_RRTYPE_SOA            6     /* marks the start of a zone of authority */
00061 #define DNS_RRTYPE_MB             7     /* a mailbox domain name (EXPERIMENTAL) */
00062 #define DNS_RRTYPE_MG             8     /* a mail group member (EXPERIMENTAL) */
00063 #define DNS_RRTYPE_MR             9     /* a mail rename domain name (EXPERIMENTAL) */
00064 #define DNS_RRTYPE_NULL           10    /* a null RR (EXPERIMENTAL) */
00065 #define DNS_RRTYPE_WKS            11    /* a well known service description */
00066 #define DNS_RRTYPE_PTR            12    /* a domain name pointer */
00067 #define DNS_RRTYPE_HINFO          13    /* host information */
00068 #define DNS_RRTYPE_MINFO          14    /* mailbox or mail list information */
00069 #define DNS_RRTYPE_MX             15    /* mail exchange */
00070 #define DNS_RRTYPE_TXT            16    /* text strings */
00071 #define DNS_RRTYPE_AAAA           28    /* IPv6 address */
00072 #define DNS_RRTYPE_SRV            33    /* service location */
00073 #define DNS_RRTYPE_ANY            255   /* any type */
00074 
00075 /* DNS field CLASS used for "Resource Records" */
00076 #define DNS_RRCLASS_IN            1     /* the Internet */
00077 #define DNS_RRCLASS_CS            2     /* the CSNET class (Obsolete - used only for examples in some obsolete RFCs) */
00078 #define DNS_RRCLASS_CH            3     /* the CHAOS class */
00079 #define DNS_RRCLASS_HS            4     /* Hesiod [Dyer 87] */
00080 #define DNS_RRCLASS_ANY           255   /* any class */
00081 #define DNS_RRCLASS_FLUSH         0x800 /* Flush bit */
00082 
00083 /* DNS protocol flags */
00084 #define DNS_FLAG1_RESPONSE        0x80
00085 #define DNS_FLAG1_OPCODE_STATUS   0x10
00086 #define DNS_FLAG1_OPCODE_INVERSE  0x08
00087 #define DNS_FLAG1_OPCODE_STANDARD 0x00
00088 #define DNS_FLAG1_AUTHORATIVE     0x04
00089 #define DNS_FLAG1_TRUNC           0x02
00090 #define DNS_FLAG1_RD              0x01
00091 #define DNS_FLAG2_RA              0x80
00092 #define DNS_FLAG2_ERR_MASK        0x0f
00093 #define DNS_FLAG2_ERR_NONE        0x00
00094 #define DNS_FLAG2_ERR_NAME        0x03
00095 
00096 #define DNS_HDR_GET_OPCODE(hdr) ((((hdr)->flags1) >> 3) & 0xF)
00097 
00098 #ifdef PACK_STRUCT_USE_INCLUDES
00099 #  include "arch/bpstruct.h"
00100 #endif
00101 PACK_STRUCT_BEGIN
00102 /** DNS message header */
00103 struct dns_hdr {
00104   PACK_STRUCT_FIELD(u16_t id);
00105   PACK_STRUCT_FLD_8(u8_t flags1);
00106   PACK_STRUCT_FLD_8(u8_t flags2);
00107   PACK_STRUCT_FIELD(u16_t numquestions);
00108   PACK_STRUCT_FIELD(u16_t numanswers);
00109   PACK_STRUCT_FIELD(u16_t numauthrr);
00110   PACK_STRUCT_FIELD(u16_t numextrarr);
00111 } PACK_STRUCT_STRUCT;
00112 PACK_STRUCT_END
00113 #ifdef PACK_STRUCT_USE_INCLUDES
00114 #  include "arch/epstruct.h"
00115 #endif
00116 #define SIZEOF_DNS_HDR 12
00117 
00118 
00119 /* Multicast DNS definitions */
00120 
00121 /** UDP port for multicast DNS queries */
00122 #ifndef DNS_MQUERY_PORT
00123 #define DNS_MQUERY_PORT             5353
00124 #endif
00125 
00126 /* IPv4 group for multicast DNS queries: 224.0.0.251 */
00127 #ifndef DNS_MQUERY_IPV4_GROUP_INIT
00128 #define DNS_MQUERY_IPV4_GROUP_INIT  IPADDR4_INIT_BYTES(224,0,0,251)
00129 #endif
00130 
00131 /* IPv6 group for multicast DNS queries: FF02::FB */
00132 #ifndef DNS_MQUERY_IPV6_GROUP_INIT
00133 #define DNS_MQUERY_IPV6_GROUP_INIT  IPADDR6_INIT_HOST(0xFF020000,0,0,0xFB)
00134 #endif
00135 
00136 #ifdef __cplusplus
00137 }
00138 #endif
00139 
00140 #endif /* LWIP_HDR_PROT_DNS_H */