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DNS.h (9273B)

      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 "nsILoadInfo.h"
     11 #include "nscore.h"
     12 #include "nsString.h"
     13 #include "prio.h"
     14 #include "prnetdb.h"
     15 #include "nsISupportsImpl.h"
     16 #include "mozilla/MemoryReporting.h"
     17 #include "nsTArray.h"
     18 
     19 #if !defined(XP_WIN)
     20 #  include <arpa/inet.h>
     21 #endif
     22 
     23 #ifdef XP_WIN
     24 #  include "winsock2.h"
     25 #endif
     26 
     27 #ifndef AF_LOCAL
     28 #  define AF_LOCAL 1  // used for named pipe
     29 #endif
     30 
     31 #define IPv6ADDR_IS_LOOPBACK(a)                                      \
     32  (((a)->u32[0] == 0) && ((a)->u32[1] == 0) && ((a)->u32[2] == 0) && \
     33   ((a)->u8[12] == 0) && ((a)->u8[13] == 0) && ((a)->u8[14] == 0) && \
     34   ((a)->u8[15] == 0x1U))
     35 
     36 #define IPv6ADDR_IS_V4MAPPED(a)                                     \
     37  (((a)->u32[0] == 0) && ((a)->u32[1] == 0) && ((a)->u8[8] == 0) && \
     38   ((a)->u8[9] == 0) && ((a)->u8[10] == 0xff) && ((a)->u8[11] == 0xff))
     39 
     40 #define IPv6ADDR_V4MAPPED_TO_IPADDR(a) ((a)->u32[3])
     41 
     42 #define IPv6ADDR_IS_UNSPECIFIED(a)                                   \
     43  (((a)->u32[0] == 0) && ((a)->u32[1] == 0) && ((a)->u32[2] == 0) && \
     44   ((a)->u32[3] == 0))
     45 
     46 namespace mozilla {
     47 namespace net {
     48 
     49 // IMPORTANT: when adding new values, always add them to the end, otherwise
     50 // it will mess up telemetry.
     51 // Stage_0: Receive the record before the http transaction is created.
     52 // Stage_1: Receive the record after the http transaction is created and the
     53 //          transaction is not dispatched.
     54 // Stage_2: Receive the record after the http transaction is dispatched.
     55 enum HTTPSSVC_RECEIVED_STAGE : uint32_t {
     56  HTTPSSVC_NOT_PRESENT = 0,
     57  HTTPSSVC_WITH_IPHINT_RECEIVED_STAGE_0 = 1,
     58  HTTPSSVC_WITHOUT_IPHINT_RECEIVED_STAGE_0 = 2,
     59  HTTPSSVC_WITH_IPHINT_RECEIVED_STAGE_1 = 3,
     60  HTTPSSVC_WITHOUT_IPHINT_RECEIVED_STAGE_1 = 4,
     61  HTTPSSVC_WITH_IPHINT_RECEIVED_STAGE_2 = 5,
     62  HTTPSSVC_WITHOUT_IPHINT_RECEIVED_STAGE_2 = 6,
     63  HTTPSSVC_NOT_USED = 7,
     64  HTTPSSVC_NO_USABLE_RECORD = 8,
     65 };
     66 
     67 #define HTTPS_RR_IS_USED(s) \
     68  (s > HTTPSSVC_NOT_PRESENT && s < HTTPSSVC_WITH_IPHINT_RECEIVED_STAGE_2)
     69 
     70 // Required buffer size for text form of an IP address.
     71 // Includes space for null termination. We make our own contants
     72 // because we don't want higher-level code depending on things
     73 // like INET6_ADDRSTRLEN and having to include the associated
     74 // platform-specific headers.
     75 #ifdef XP_WIN
     76 // Windows requires longer buffers for some reason.
     77 const int kIPv4CStrBufSize = 22;
     78 const int kIPv6CStrBufSize = 65;
     79 const int kNetAddrMaxCStrBufSize = kIPv6CStrBufSize;
     80 #else
     81 const int kIPv4CStrBufSize = 16;
     82 const int kIPv6CStrBufSize = 46;
     83 const int kLocalCStrBufSize = 108;
     84 const int kNetAddrMaxCStrBufSize = kLocalCStrBufSize;
     85 #endif
     86 
     87 // This was all created at a time in which we were using NSPR for host
     88 // resolution and we were propagating NSPR types like "PRAddrInfo" and
     89 // "PRNetAddr" all over Gecko. This made it hard to use another host
     90 // resolver -- we were locked into NSPR. The goal here is to get away
     91 // from that. We'll translate what we get from NSPR or any other host
     92 // resolution library into the types below and use them in Gecko.
     93 
     94 union IPv6Addr {
     95  uint8_t u8[16];
     96  uint16_t u16[8];
     97  uint32_t u32[4];
     98  uint64_t u64[2];
     99 };
    100 
    101 // This struct is similar to operating system structs like "sockaddr", used for
    102 // things like "connect" and "getsockname". When tempted to cast or do dumb
    103 // copies of this struct to another struct, bear compiler-computed padding
    104 // in mind. The size of this struct, and the layout of the data in it, may
    105 // not be what you expect.
    106 union NetAddr {
    107  struct {
    108    uint16_t family; /* address family (0x00ff maskable) */
    109    char data[14];   /* raw address data */
    110  } raw{};
    111  struct {
    112    uint16_t family; /* address family (AF_INET) */
    113    uint16_t port;   /* port number */
    114    uint32_t ip;     /* The actual 32 bits of address */
    115  } inet;
    116  struct {
    117    uint16_t family;   /* address family (AF_INET6) */
    118    uint16_t port;     /* port number */
    119    uint32_t flowinfo; /* routing information */
    120    IPv6Addr ip;       /* the actual 128 bits of address */
    121    uint32_t scope_id; /* set of interfaces for a scope */
    122  } inet6;
    123 #if defined(XP_UNIX) || defined(XP_WIN)
    124  struct {           /* Unix domain socket or
    125                        Windows Named Pipes address */
    126    uint16_t family; /* address family (AF_UNIX) */
    127    char path[104];  /* null-terminated pathname */
    128  } local;
    129 #endif
    130  // introduced to support nsTArray<NetAddr> comparisons and sorting
    131  bool operator==(const NetAddr& other) const;
    132  bool operator<(const NetAddr& other) const;
    133 
    134  // Use the default copy constructor/assignment operator, which will memcpy
    135  // under the hood.
    136  NetAddr(const NetAddr&) = default;
    137  inline NetAddr& operator=(const NetAddr& other) = default;
    138 
    139  NetAddr() { memset((void*)this, 0, sizeof(NetAddr)); }
    140  explicit NetAddr(const PRNetAddr* prAddr);
    141 
    142  // Will parse aString into a NetAddr using PR_StringToNetAddr.
    143  // Returns an error code if parsing fails.
    144  // If aPort is non-0 will set the NetAddr's port to (the network endian
    145  // value of) that.
    146  nsresult InitFromString(const nsACString& aString, uint16_t aPort = 0);
    147 
    148  bool IsIPAddrAny() const;
    149  bool IsLoopbackAddr() const;
    150  bool IsLoopBackAddressWithoutIPv6Mapping() const;
    151  bool IsIPAddrV4() const;
    152  bool IsBenchMarkingAddress() const;
    153  bool IsIPAddrV4Mapped() const;
    154  bool IsIPAddrLocal() const;
    155  bool IsIPAddrShared() const;
    156  nsresult GetPort(uint16_t* aResult) const;
    157  bool ToStringBuffer(char* buf, uint32_t bufSize) const;
    158  nsCString ToString() const;
    159  void ToAddrPortString(nsACString& aOutput) const;
    160  nsILoadInfo::IPAddressSpace GetIpAddressSpace() const;
    161 };
    162 
    163 enum class DNSResolverType : uint32_t { Native = 0, TRR };
    164 
    165 class AddrInfo {
    166  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(AddrInfo)
    167 
    168 public:
    169  static const uint32_t NO_TTL_DATA = (uint32_t)-1;
    170 
    171  // Creates an AddrInfo object.
    172  explicit AddrInfo(const nsACString& host, const PRAddrInfo* prAddrInfo,
    173                    bool disableIPv4, bool filterNameCollision,
    174                    const nsACString& cname);
    175 
    176  // Creates a basic AddrInfo object (initialize only the host, cname and TRR
    177  // type).
    178  explicit AddrInfo(const nsACString& host, const nsACString& cname,
    179                    DNSResolverType aResolverType, unsigned int aTRRType,
    180                    nsTArray<NetAddr>&& addresses);
    181 
    182  // Creates a basic AddrInfo object (initialize only the host and TRR
    183  // status).
    184  explicit AddrInfo(const nsACString& host, DNSResolverType aResolverType,
    185                    unsigned int aTRRType, nsTArray<NetAddr>&& addresses,
    186                    uint32_t aTTL = NO_TTL_DATA);
    187 
    188  explicit AddrInfo(const AddrInfo* src);  // copy
    189 
    190  size_t SizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const;
    191 
    192  bool IsTRR() const { return mResolverType == DNSResolverType::TRR; }
    193  DNSResolverType ResolverType() const { return mResolverType; }
    194  unsigned int TRRType() { return mTRRType; }
    195 
    196  double GetTrrFetchDuration() { return mTrrFetchDuration; }
    197  double GetTrrFetchDurationNetworkOnly() {
    198    return mTrrFetchDurationNetworkOnly;
    199  }
    200 
    201  const nsTArray<NetAddr>& Addresses() { return mAddresses; }
    202  const nsCString& Hostname() { return mHostName; }
    203  const nsCString& CanonicalHostname() { return mCanonicalName; }
    204  uint32_t TTL() { return ttl; }
    205 
    206  class MOZ_STACK_CLASS AddrInfoBuilder {
    207   public:
    208    explicit AddrInfoBuilder(AddrInfo* aInfo) {
    209      mInfo = new AddrInfo(aInfo);  // Clone it
    210    }
    211 
    212    void SetTrrFetchDurationNetworkOnly(double aTime) {
    213      mInfo->mTrrFetchDurationNetworkOnly = aTime;
    214    }
    215 
    216    void SetTrrFetchDuration(double aTime) { mInfo->mTrrFetchDuration = aTime; }
    217 
    218    void SetTTL(uint32_t aTTL) { mInfo->ttl = aTTL; }
    219 
    220    void SetAddresses(nsTArray<NetAddr>&& addresses) {
    221      mInfo->mAddresses = std::move(addresses);
    222    }
    223 
    224    template <class Comparator>
    225    void SortAddresses(const Comparator& aComp) {
    226      mInfo->mAddresses.Sort(aComp);
    227    }
    228 
    229    void SetCanonicalHostname(const nsACString& aCname) {
    230      mInfo->mCanonicalName = aCname;
    231    }
    232 
    233    already_AddRefed<AddrInfo> Finish() { return mInfo.forget(); }
    234 
    235   private:
    236    RefPtr<AddrInfo> mInfo;
    237  };
    238 
    239  AddrInfoBuilder Build() { return AddrInfoBuilder(this); }
    240 
    241 private:
    242  ~AddrInfo();
    243  uint32_t ttl = NO_TTL_DATA;
    244 
    245  nsCString mHostName;
    246  nsCString mCanonicalName;
    247  DNSResolverType mResolverType = DNSResolverType::Native;
    248  unsigned int mTRRType = 0;
    249  double mTrrFetchDuration = 0;
    250  double mTrrFetchDurationNetworkOnly = 0;
    251 
    252  nsTArray<NetAddr> mAddresses;
    253 };
    254 
    255 // Copies the contents of a PRNetAddr to a NetAddr.
    256 // Does not do a ptr safety check!
    257 void PRNetAddrToNetAddr(const PRNetAddr* prAddr, NetAddr* addr);
    258 
    259 // Copies the contents of a NetAddr to a PRNetAddr.
    260 // Does not do a ptr safety check!
    261 void NetAddrToPRNetAddr(const NetAddr* addr, PRNetAddr* prAddr);
    262 
    263 bool IsLoopbackHostname(const nsACString& aAsciiHost);
    264 
    265 bool HostIsIPLiteral(const nsACString& aAsciiHost);
    266 
    267 }  // namespace net
    268 }  // namespace mozilla
    269 
    270 #endif  // DNS_h_