net/quic/quic_utils.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4 //
   5 // Some helpers for quic
   6
   7 #ifndef NET_QUIC_QUIC_UTILS_H_
   8 #define NET_QUIC_QUIC_UTILS_H_
   9
  10 #include "net/base/int128.h"
  11 #include "net/base/net_export.h"
  12 #include "net/quic/quic_protocol.h"
  13
  14 namespace net {
  15
  16 class NET_EXPORT_PRIVATE QuicUtils {
  17  public:
  18   enum Priority {
  19     LOCAL_PRIORITY,
  20     PEER_PRIORITY,
  21   };
  22
  23   // returns the 64 bit FNV1a hash of the data.  See
  24   // http://www.isthe.com/chongo/tech/comp/fnv/index.html#FNV-param
  25   static uint64 FNV1a_64_Hash(const char* data, int len);
  26
  27   // returns the 128 bit FNV1a hash of the data.  See
  28   // http://www.isthe.com/chongo/tech/comp/fnv/index.html#FNV-param
  29   static uint128 FNV1a_128_Hash(const char* data, int len);
  30
  31   // FindMutualTag sets |out_result| to the first tag in the priority list that
  32   // is also in the other list and returns true. If there is no intersection it
  33   // returns false.
  34   //
  35   // Which list has priority is determined by |priority|.
  36   //
  37   // If |out_index| is non-NULL and a match is found then the index of that
  38   // match in |their_tags| is written to |out_index|.
  39   static bool FindMutualTag(const QuicTagVector& our_tags,
  40                             const QuicTag* their_tags,
  41                             size_t num_their_tags,
  42                             Priority priority,
  43                             QuicTag* out_result,
  44                             size_t* out_index);
  45
  46   // SerializeUint128 writes |v| in little-endian form to |out|.
  47   static void SerializeUint128(uint128 v, uint8* out);
  48
  49   // SerializeUint128 writes the first 96 bits of |v| in little-endian form
  50   // to |out|.
  51   static void SerializeUint128Short(uint128 v, uint8* out);
  52
  53   // Returns the name of the QuicRstStreamErrorCode as a char*
  54   static const char* StreamErrorToString(QuicRstStreamErrorCode error);
  55
  56   // Returns the name of the QuicErrorCode as a char*
  57   static const char* ErrorToString(QuicErrorCode error);
  58
  59   // Returns the level of encryption as a char*
  60   static const char* EncryptionLevelToString(EncryptionLevel level);
  61
  62   // TagToString is a utility function for pretty-printing handshake messages
  63   // that converts a tag to a string. It will try to maintain the human friendly
  64   // name if possible (i.e. kABCD -> "ABCD"), or will just treat it as a number
  65   // if not.
  66   static std::string TagToString(QuicTag tag);
  67
  68   // Given a binary buffer, return a hex+ASCII dump in the style of
  69   // tcpdump's -X and -XX options:
  70   // "0x0000:  0090 69bd 5400 000d 610f 0189 0800 4500  ..i.T...a.....E.\n"
  71   // "0x0010:  001c fb98 4000 4001 7e18 d8ef 2301 455d  ....@.@.~...#.E]\n"
  72   // "0x0020:  7fe2 0800 6bcb 0bc6 806e                 ....k....n\n"
  73   static std::string StringToHexASCIIDump(base::StringPiece in_buffer);
  74
  75   static char* AsChars(unsigned char* data) {
  76     return reinterpret_cast<char*>(data);
  77   }
  78
  79   static QuicPriority LowestPriority();
  80
  81   static QuicPriority HighestPriority();
  82 };
  83
  84 // Utility function that returns an IOVector object wrapped around |str|.
  85 inline IOVector MakeIOVector(base::StringPiece str) {
  86   IOVector iov;
  87   iov.Append(const_cast<char*>(str.data()), str.size());
  88   return iov;
  89 }
  90
  91 }  // namespace net
  92
  93 #endif  // NET_QUIC_QUIC_UTILS_H_