apt-pkg/contrib/hashes.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: hashes.cc,v 1.1 2001/03/06 07:15:29 jgg Exp $
   4 /* ######################################################################
   5
   6    Hashes - Simple wrapper around the hash functions
   7
   8    This is just used to make building the methods simpler, this is the
   9    only interface required..
  10
  11    ##################################################################### */
  12                                                                         /*}}}*/
  13 // Include Files                                                        /*{{{*/
  14 #include <config.h>
  15
  16 #include <apt-pkg/hashes.h>
  17 #include <apt-pkg/fileutl.h>
  18 #include <apt-pkg/configuration.h>
  19 #include <apt-pkg/md5.h>
  20 #include <apt-pkg/sha1.h>
  21 #include <apt-pkg/sha2.h>
  22
  23 #include <stddef.h>
  24 #include <algorithm>
  25 #include <unistd.h>
  26 #include <string>
  27 #include <iostream>
  28                                                                         /*}}}*/
  29
  30 const char* HashString::_SupportedHashes[] =
  31 {
  32    "SHA512", "SHA256", "SHA1", "MD5Sum", NULL
  33 };
  34
  35 HashString::HashString()
  36 {
  37 }
  38
  39 HashString::HashString(std::string Type, std::string Hash) : Type(Type), Hash(Hash)
  40 {
  41 }
  42
  43 HashString::HashString(std::string StringedHash)                        /*{{{*/
  44 {
  45    // legacy: md5sum without "MD5Sum:" prefix
  46    if (StringedHash.find(":") == std::string::npos && StringedHash.size() == 32)
  47    {
  48       Type = "MD5Sum";
  49       Hash = StringedHash;
  50       return;
  51    }
  52    std::string::size_type pos = StringedHash.find(":");
  53    Type = StringedHash.substr(0,pos);
  54    Hash = StringedHash.substr(pos+1, StringedHash.size() - pos);
  55
  56    if(_config->FindB("Debug::Hashes",false) == true)
  57       std::clog << "HashString(string): " << Type << " : " << Hash << std::endl;
  58 }
  59                                                                         /*}}}*/
  60 bool HashString::VerifyFile(std::string filename) const                 /*{{{*/
  61 {
  62    std::string fileHash = GetHashForFile(filename);
  63
  64    if(_config->FindB("Debug::Hashes",false) == true)
  65       std::clog << "HashString::VerifyFile: got: " << fileHash << " expected: " << toStr() << std::endl;
  66
  67    return (fileHash == Hash);
  68 }
  69                                                                         /*}}}*/
  70 bool HashString::FromFile(std::string filename)                         /*{{{*/
  71 {
  72    // pick the strongest hash
  73    if (Type == "")
  74       Type = _SupportedHashes[0];
  75
  76    Hash = GetHashForFile(filename);
  77    return true;
  78 }
  79                                                                         /*}}}*/
  80 std::string HashString::GetHashForFile(std::string filename) const      /*{{{*/
  81 {
  82    std::string fileHash;
  83
  84    FileFd Fd(filename, FileFd::ReadOnly);
  85    if(Type == "MD5Sum")
  86    {
  87       MD5Summation MD5;
  88       MD5.AddFD(Fd);
  89       fileHash = (std::string)MD5.Result();
  90    }
  91    else if (Type == "SHA1")
  92    {
  93       SHA1Summation SHA1;
  94       SHA1.AddFD(Fd);
  95       fileHash = (std::string)SHA1.Result();
  96    }
  97    else if (Type == "SHA256")
  98    {
  99       SHA256Summation SHA256;
 100       SHA256.AddFD(Fd);
 101       fileHash = (std::string)SHA256.Result();
 102    }
 103    else if (Type == "SHA512")
 104    {
 105       SHA512Summation SHA512;
 106       SHA512.AddFD(Fd);
 107       fileHash = (std::string)SHA512.Result();
 108    }
 109    Fd.Close();
 110
 111    return fileHash;
 112 }
 113                                                                         /*}}}*/
 114 const char** HashString::SupportedHashes()
 115 {
 116    return _SupportedHashes;
 117 }
 118
 119 APT_PURE bool HashString::empty() const
 120 {
 121    return (Type.empty() || Hash.empty());
 122 }
 123
 124 std::string HashString::toStr() const
 125 {
 126    return Type + std::string(":") + Hash;
 127 }
 128
 129 // Hashes::AddFD - Add the contents of the FD                           /*{{{*/
 130 // ---------------------------------------------------------------------
 131 /* */
 132 bool Hashes::AddFD(int const Fd,unsigned long long Size, bool const addMD5,
 133                    bool const addSHA1, bool const addSHA256, bool const addSHA512)
 134 {
 135    unsigned char Buf[64*64];
 136    bool const ToEOF = (Size == 0);
 137    while (Size != 0 || ToEOF)
 138    {
 139       unsigned long long n = sizeof(Buf);
 140       if (!ToEOF) n = std::min(Size, n);
 141       ssize_t const Res = read(Fd,Buf,n);
 142       if (Res < 0 || (!ToEOF && Res != (ssize_t) n)) // error, or short read
 143          return false;
 144       if (ToEOF && Res == 0) // EOF
 145          break;
 146       Size -= Res;
 147       if (addMD5 == true)
 148          MD5.Add(Buf,Res);
 149       if (addSHA1 == true)
 150          SHA1.Add(Buf,Res);
 151       if (addSHA256 == true)
 152          SHA256.Add(Buf,Res);
 153       if (addSHA512 == true)
 154          SHA512.Add(Buf,Res);
 155    }
 156    return true;
 157 }
 158 bool Hashes::AddFD(FileFd &Fd,unsigned long long Size, bool const addMD5,
 159                    bool const addSHA1, bool const addSHA256, bool const addSHA512)
 160 {
 161    unsigned char Buf[64*64];
 162    bool const ToEOF = (Size == 0);
 163    while (Size != 0 || ToEOF)
 164    {
 165       unsigned long long n = sizeof(Buf);
 166       if (!ToEOF) n = std::min(Size, n);
 167       unsigned long long a = 0;
 168       if (Fd.Read(Buf, n, &a) == false) // error
 169          return false;
 170       if (ToEOF == false)
 171       {
 172          if (a != n) // short read
 173             return false;
 174       }
 175       else if (a == 0) // EOF
 176          break;
 177       Size -= a;
 178       if (addMD5 == true)
 179          MD5.Add(Buf, a);
 180       if (addSHA1 == true)
 181          SHA1.Add(Buf, a);
 182       if (addSHA256 == true)
 183          SHA256.Add(Buf, a);
 184       if (addSHA512 == true)
 185          SHA512.Add(Buf, a);
 186    }
 187    return true;
 188 }
 189                                                                         /*}}}*/