netwerk/dns/DNS.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef DNS_h_
   8 #define DNS_h_
   9
  10 #include "nscore.h"
  11 #include "prio.h"
  12 #include "prnetdb.h"
  13 #include "plstr.h"
  14 #include "mozilla/LinkedList.h"
  15 #include "mozilla/MemoryReporting.h"
  16
  17 #if !defined(XP_WIN)
  18 #include <arpa/inet.h>
  19 #endif
  20
  21 #ifdef XP_WIN
  22 #include "winsock2.h"
  23 #endif
  24
  25 #define IPv6ADDR_IS_LOOPBACK(a) \
  26   (((a)->u32[0] == 0)     &&    \
  27    ((a)->u32[1] == 0)     &&    \
  28    ((a)->u32[2] == 0)     &&    \
  29    ((a)->u8[12] == 0)     &&    \
  30    ((a)->u8[13] == 0)     &&    \
  31    ((a)->u8[14] == 0)     &&    \
  32    ((a)->u8[15] == 0x1U))
  33
  34 #define IPv6ADDR_IS_V4MAPPED(a) \
  35   (((a)->u32[0] == 0)     &&    \
  36    ((a)->u32[1] == 0)     &&    \
  37    ((a)->u8[8] == 0)      &&    \
  38    ((a)->u8[9] == 0)      &&    \
  39    ((a)->u8[10] == 0xff)  &&    \
  40    ((a)->u8[11] == 0xff))
  41
  42 #define IPv6ADDR_V4MAPPED_TO_IPADDR(a) ((a)->u32[3])
  43
  44 #define IPv6ADDR_IS_UNSPECIFIED(a) \
  45   (((a)->u32[0] == 0)  &&          \
  46    ((a)->u32[1] == 0)  &&          \
  47    ((a)->u32[2] == 0)  &&          \
  48    ((a)->u32[3] == 0))
  49
  50 namespace mozilla {
  51 namespace net {
  52
  53 // Required buffer size for text form of an IP address.
  54 // Includes space for null termination. We make our own contants
  55 // because we don't want higher-level code depending on things
  56 // like INET6_ADDRSTRLEN and having to include the associated
  57 // platform-specific headers.
  58 #ifdef XP_WIN
  59 // Windows requires longer buffers for some reason.
  60 const int kIPv4CStrBufSize = 22;
  61 const int kIPv6CStrBufSize = 65;
  62 const int kNetAddrMaxCStrBufSize = kIPv6CStrBufSize;
  63 #else
  64 const int kIPv4CStrBufSize = 16;
  65 const int kIPv6CStrBufSize = 46;
  66 const int kLocalCStrBufSize = 108;
  67 const int kNetAddrMaxCStrBufSize = kLocalCStrBufSize;
  68 #endif
  69
  70 // This was all created at a time in which we were using NSPR for host
  71 // resolution and we were propagating NSPR types like "PRAddrInfo" and
  72 // "PRNetAddr" all over Gecko. This made it hard to use another host
  73 // resolver -- we were locked into NSPR. The goal here is to get away
  74 // from that. We'll translate what we get from NSPR or any other host
  75 // resolution library into the types below and use them in Gecko.
  76
  77 union IPv6Addr {
  78   uint8_t  u8[16];
  79   uint16_t u16[8];
  80   uint32_t u32[4];
  81   uint64_t u64[2];
  82 };
  83
  84 // This struct is similar to operating system structs like "sockaddr", used for
  85 // things like "connect" and "getsockname". When tempted to cast or do dumb
  86 // copies of this struct to another struct, bear compiler-computed padding
  87 // in mind. The size of this struct, and the layout of the data in it, may
  88 // not be what you expect.
  89 union NetAddr {
  90   struct {
  91     uint16_t family;                /* address family (0x00ff maskable) */
  92     char data[14];                  /* raw address data */
  93   } raw;
  94   struct {
  95     uint16_t family;                /* address family (AF_INET) */
  96     uint16_t port;                  /* port number */
  97     uint32_t ip;                    /* The actual 32 bits of address */
  98   } inet;
  99   struct {
 100     uint16_t family;                /* address family (AF_INET6) */
 101     uint16_t port;                  /* port number */
 102     uint32_t flowinfo;              /* routing information */
 103     IPv6Addr ip;                    /* the actual 128 bits of address */
 104     uint32_t scope_id;              /* set of interfaces for a scope */
 105   } inet6;
 106 #if defined(XP_UNIX)
 107   struct {                          /* Unix domain socket address */
 108     uint16_t family;                /* address family (AF_UNIX) */
 109     char path[104];                 /* null-terminated pathname */
 110   } local;
 111 #endif
 112   // introduced to support nsTArray<NetAddr> (for DNSRequestParent.cpp)
 113   bool operator == (const NetAddr& other) const;
 114 };
 115
 116 // This class wraps a NetAddr union to provide C++ linked list
 117 // capabilities and other methods. It is created from a PRNetAddr,
 118 // which is converted to a mozilla::dns::NetAddr.
 119 class NetAddrElement : public LinkedListElement<NetAddrElement> {
 120 public:
 121   explicit NetAddrElement(const PRNetAddr *prNetAddr);
 122   NetAddrElement(const NetAddrElement& netAddr);
 123   ~NetAddrElement();
 124
 125   NetAddr mAddress;
 126 };
 127
 128 class AddrInfo {
 129 public:
 130   // Creates an AddrInfo object. It calls the AddrInfo(const char*, const char*)
 131   // to initialize the host and the cname.
 132   AddrInfo(const char *host, const PRAddrInfo *prAddrInfo, bool disableIPv4,
 133            const char *cname);
 134
 135   // Creates a basic AddrInfo object (initialize only the host and the cname).
 136   AddrInfo(const char *host, const char *cname);
 137   ~AddrInfo();
 138
 139   void AddAddress(NetAddrElement *address);
 140
 141   size_t SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const;
 142
 143   char *mHostName;
 144   char *mCanonicalName;
 145   LinkedList<NetAddrElement> mAddresses;
 146
 147 private:
 148   void Init(const char *host, const char *cname);
 149 };
 150
 151 // Copies the contents of a PRNetAddr to a NetAddr.
 152 // Does not do a ptr safety check!
 153 void PRNetAddrToNetAddr(const PRNetAddr *prAddr, NetAddr *addr);
 154
 155 // Copies the contents of a NetAddr to a PRNetAddr.
 156 // Does not do a ptr safety check!
 157 void NetAddrToPRNetAddr(const NetAddr *addr, PRNetAddr *prAddr);
 158
 159 bool NetAddrToString(const NetAddr *addr, char *buf, uint32_t bufSize);
 160
 161 bool IsLoopBackAddress(const NetAddr *addr);
 162
 163 bool IsIPAddrAny(const NetAddr *addr);
 164
 165 bool IsIPAddrV4Mapped(const NetAddr *addr);
 166
 167 bool IsIPAddrLocal(const NetAddr *addr);
 168
 169 nsresult GetPort(const NetAddr *aAddr, uint16_t *aResult);
 170
 171 } // namespace net
 172 } // namespace mozilla
 173
 174 #endif // DNS_h_