netwerk/dns/DNS.h

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #ifndef DNS_h_
   6 #define DNS_h_
   7
   8 #include "nscore.h"
   9 #include "prio.h"
  10 #include "prnetdb.h"
  11 #include "mozilla/LinkedList.h"
  12
  13 #if !defined(XP_WIN) && !defined(XP_OS2)
  14 #include <arpa/inet.h>
  15 #endif
  16
  17 #ifdef XP_WIN
  18 #include "winsock2.h"
  19 #endif
  20
  21 #define IPv6ADDR_IS_LOOPBACK(a) \
  22   (((a)->u32[0] == 0)     &&    \
  23    ((a)->u32[1] == 0)     &&    \
  24    ((a)->u32[2] == 0)     &&    \
  25    ((a)->u8[12] == 0)     &&    \
  26    ((a)->u8[13] == 0)     &&    \
  27    ((a)->u8[14] == 0)     &&    \
  28    ((a)->u8[15] == 0x1U))
  29
  30 #define IPv6ADDR_IS_V4MAPPED(a) \
  31   (((a)->u32[0] == 0)     &&    \
  32    ((a)->u32[1] == 0)     &&    \
  33    ((a)->u8[8] == 0)      &&    \
  34    ((a)->u8[9] == 0)      &&    \
  35    ((a)->u8[10] == 0xff)  &&    \
  36    ((a)->u8[11] == 0xff))
  37
  38 #define IPv6ADDR_V4MAPPED_TO_IPADDR(a) ((a)->u32[3])
  39
  40 #define IPv6ADDR_IS_UNSPECIFIED(a) \
  41   (((a)->u32[0] == 0)  &&          \
  42    ((a)->u32[1] == 0)  &&          \
  43    ((a)->u32[2] == 0)  &&          \
  44    ((a)->u32[3] == 0))
  45
  46 namespace mozilla {
  47 namespace net {
  48
  49 // Required buffer size for text form of an IP address.
  50 // Includes space for null termination. We make our own contants
  51 // because we don't want higher-level code depending on things
  52 // like INET6_ADDRSTRLEN and having to include the associated
  53 // platform-specific headers.
  54 #ifdef XP_WIN
  55 // Windows requires longer buffers for some reason.
  56 const int kIPv4CStrBufSize = 22;
  57 const int kIPv6CStrBufSize = 65;
  58 #else
  59 const int kIPv4CStrBufSize = 16;
  60 const int kIPv6CStrBufSize = 46;
  61 #endif
  62
  63 // This was all created at a time in which we were using NSPR for host
  64 // resolution and we were propagating NSPR types like "PRAddrInfo" and
  65 // "PRNetAddr" all over Gecko. This made it hard to use another host
  66 // resolver -- we were locked into NSPR. The goal here is to get away
  67 // from that. We'll translate what we get from NSPR or any other host
  68 // resolution library into the types below and use them in Gecko.
  69
  70 union IPv6Addr {
  71   uint8_t  u8[16];
  72   uint16_t u16[8];
  73   uint32_t u32[4];
  74   uint64_t u64[2];
  75 };
  76
  77 // This struct is similar to operating system structs like "sockaddr", used for
  78 // things like "connect" and "getsockname". When tempted to cast or do dumb
  79 // copies of this struct to another struct, bear compiler-computed padding
  80 // in mind. The size of this struct, and the layout of the data in it, may
  81 // not be what you expect.
  82 union NetAddr {
  83   struct {
  84     uint16_t family;                /* address family (0x00ff maskable) */
  85     char data[14];                  /* raw address data */
  86   } raw;
  87   struct {
  88     uint16_t family;                /* address family (AF_INET) */
  89     uint16_t port;                  /* port number */
  90     uint32_t ip;                    /* The actual 32 bits of address */
  91   } inet;
  92   struct {
  93     uint16_t family;                /* address family (AF_INET6) */
  94     uint16_t port;                  /* port number */
  95     uint32_t flowinfo;              /* routing information */
  96     IPv6Addr ip;                    /* the actual 128 bits of address */
  97     uint32_t scope_id;              /* set of interfaces for a scope */
  98   } inet6;
  99 #if defined(XP_UNIX) || defined(XP_OS2)
 100   struct {                          /* Unix domain socket address */
 101     uint16_t family;                /* address family (AF_UNIX) */
 102 #ifdef XP_OS2
 103     char path[108];                 /* null-terminated pathname */
 104 #else
 105     char path[104];                 /* null-terminated pathname */
 106 #endif
 107   } local;
 108 #endif
 109 };
 110
 111 // This class wraps a NetAddr union to provide C++ linked list
 112 // capabilities and other methods. It is created from a PRNetAddr,
 113 // which is converted to a mozilla::dns::NetAddr.
 114 class NetAddrElement : public LinkedListElement<NetAddrElement> {
 115 public:
 116   NetAddrElement(const PRNetAddr *prNetAddr);
 117   ~NetAddrElement();
 118
 119   NetAddr mAddress;
 120 };
 121
 122 class AddrInfo {
 123 public:
 124   AddrInfo(const char *host, const PRAddrInfo *prAddrInfo, bool disableIPv4);
 125   ~AddrInfo();
 126
 127   char *mHostName;
 128   LinkedList<NetAddrElement> mAddresses;
 129 };
 130
 131 // Copies the contents of a PRNetAddr to a NetAddr.
 132 // Does not do a ptr safety check!
 133 void PRNetAddrToNetAddr(const PRNetAddr *prAddr, NetAddr *addr);
 134
 135 // Copies the contents of a NetAddr to a PRNetAddr.
 136 // Does not do a ptr safety check!
 137 void NetAddrToPRNetAddr(const NetAddr *addr, PRNetAddr *prAddr);
 138
 139 bool NetAddrToString(const NetAddr *addr, char *buf, uint32_t bufSize);
 140
 141 bool IsLoopBackAddress(const NetAddr *addr);
 142
 143 bool IsIPAddrAny(const NetAddr *addr);
 144
 145 bool IsIPAddrV4Mapped(const NetAddr *addr);
 146
 147 } // namespace net
 148 } // namespace mozilla
 149
 150 #endif // DNS_h_