apt-private/private-download.cc

   1 // Include Files                                                        /*{{{*/
   2 #include <config.h>
   3
   4 #include <apt-pkg/acquire.h>
   5 #include <apt-pkg/acquire-item.h>
   6 #include <apt-pkg/configuration.h>
   7 #include <apt-pkg/error.h>
   8 #include <apt-pkg/fileutl.h>
   9 #include <apt-pkg/strutl.h>
  10
  11 #include <apt-private/private-output.h>
  12 #include <apt-private/private-download.h>
  13
  14 #include <fstream>
  15 #include <string>
  16 #include <vector>
  17
  18 #include <unistd.h>
  19 #include <sys/types.h>
  20 #include <pwd.h>
  21 #include <fcntl.h>
  22 #include <sys/vfs.h>
  23 #include <sys/statvfs.h>
  24 #include <errno.h>
  25
  26 #include <apti18n.h>
  27                                                                         /*}}}*/
  28
  29 bool CheckDropPrivsMustBeDisabled(pkgAcquire &Fetcher)                  /*{{{*/
  30 {
  31    // no need/possibility to drop privs
  32    if(getuid() != 0)
  33       return true;
  34
  35    // the user does not want to drop privs
  36    std::string SandboxUser = _config->Find("APT::Sandbox::User");
  37    if (SandboxUser.empty())
  38       return true;
  39
  40    struct passwd const * const pw = getpwnam(SandboxUser.c_str());
  41    if (pw == NULL)
  42       return true;
  43
  44    if (seteuid(pw->pw_uid) != 0)
  45       return _error->Errno("seteuid", "seteuid %u failed", pw->pw_uid);
  46
  47    bool res = true;
  48    // check if we can write to destfile
  49    for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin();
  50         I != Fetcher.ItemsEnd() && res == true; ++I)
  51    {
  52       int fd = open((*I)->DestFile.c_str(), O_CREAT | O_RDWR, 0600);
  53       if (fd < 0)
  54       {
  55          res = false;
  56          std::string msg;
  57          strprintf(msg, _("Can't drop privileges for downloading as file '%s' couldn't be accessed by user '%s'."),
  58                (*I)->DestFile.c_str(), SandboxUser.c_str());
  59          c0out << msg << std::endl;
  60          _config->Set("APT::Sandbox::User", "");
  61       }
  62       close(fd);
  63    }
  64
  65    if (seteuid(0) != 0)
  66       return _error->Errno("seteuid", "seteuid %u failed", 0);
  67
  68    return res;
  69 }
  70                                                                         /*}}}*/
  71 // CheckAuth - check if each download comes form a trusted source       /*{{{*/
  72 bool CheckAuth(pkgAcquire& Fetcher, bool const PromptUser)
  73 {
  74    std::string UntrustedList;
  75    for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin(); I < Fetcher.ItemsEnd(); ++I)
  76       if (!(*I)->IsTrusted())
  77           UntrustedList += std::string((*I)->ShortDesc()) + " ";
  78
  79    if (UntrustedList == "")
  80       return true;
  81
  82    return AuthPrompt(UntrustedList, PromptUser);
  83 }
  84
  85 bool AuthPrompt(std::string const &UntrustedList, bool const PromptUser)
  86 {
  87    ShowList(c2out,_("WARNING: The following packages cannot be authenticated!"),UntrustedList,"");
  88
  89    if (_config->FindB("APT::Get::AllowUnauthenticated",false) == true)
  90    {
  91       c2out << _("Authentication warning overridden.\n");
  92       return true;
  93    }
  94
  95    if (PromptUser == false)
  96       return _error->Error(_("Some packages could not be authenticated"));
  97
  98    if (_config->FindI("quiet",0) < 2
  99        && _config->FindB("APT::Get::Assume-Yes",false) == false)
 100    {
 101       c2out << _("Install these packages without verification?") << std::flush;
 102       if (!YnPrompt(false))
 103          return _error->Error(_("Some packages could not be authenticated"));
 104
 105       return true;
 106    }
 107    else if (_config->FindB("APT::Get::Force-Yes",false) == true)
 108       return true;
 109
 110    return _error->Error(_("There are problems and -y was used without --force-yes"));
 111 }
 112                                                                         /*}}}*/
 113 bool AcquireRun(pkgAcquire &Fetcher, int const PulseInterval, bool * const Failure, bool * const TransientNetworkFailure)/*{{{*/
 114 {
 115    pkgAcquire::RunResult res;
 116    if(PulseInterval > 0)
 117       res = Fetcher.Run(PulseInterval);
 118    else
 119       res = Fetcher.Run();
 120
 121    if (res == pkgAcquire::Failed)
 122       return false;
 123
 124    for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin();
 125         I != Fetcher.ItemsEnd(); ++I)
 126    {
 127
 128       if ((*I)->Status == pkgAcquire::Item::StatDone &&
 129             (*I)->Complete == true)
 130          continue;
 131
 132       if (TransientNetworkFailure != NULL && (*I)->Status == pkgAcquire::Item::StatIdle)
 133       {
 134          *TransientNetworkFailure = true;
 135          continue;
 136       }
 137
 138       ::URI uri((*I)->DescURI());
 139       uri.User.clear();
 140       uri.Password.clear();
 141       std::string descUri = std::string(uri);
 142       _error->Error(_("Failed to fetch %s  %s\n"), descUri.c_str(),
 143             (*I)->ErrorText.c_str());
 144
 145       if (Failure != NULL)
 146          *Failure = true;
 147    }
 148
 149    return true;
 150 }
 151                                                                         /*}}}*/
 152 bool CheckFreeSpaceBeforeDownload(std::string const &Dir, unsigned long long FetchBytes)/*{{{*/
 153 {
 154    uint32_t const RAMFS_MAGIC = 0x858458f6;
 155    /* Check for enough free space, but only if we are actually going to
 156       download */
 157    if (_config->FindB("APT::Get::Print-URIs", false) == true ||
 158        _config->FindB("APT::Get::Download", true) == false)
 159       return true;
 160
 161    struct statvfs Buf;
 162    if (statvfs(Dir.c_str(),&Buf) != 0) {
 163       if (errno == EOVERFLOW)
 164          return _error->WarningE("statvfs",_("Couldn't determine free space in %s"),
 165                Dir.c_str());
 166       else
 167          return _error->Errno("statvfs",_("Couldn't determine free space in %s"),
 168                Dir.c_str());
 169    }
 170    else
 171    {
 172       unsigned long long const FreeBlocks = _config->Find("APT::Sandbox::User").empty() ? Buf.f_bfree : Buf.f_bavail;
 173       if (FreeBlocks < (FetchBytes / Buf.f_bsize))
 174       {
 175          struct statfs Stat;
 176          if (statfs(Dir.c_str(),&Stat) != 0
 177 #if HAVE_STRUCT_STATFS_F_TYPE
 178                || Stat.f_type != RAMFS_MAGIC
 179 #endif
 180             )
 181             return _error->Error(_("You don't have enough free space in %s."),
 182                   Dir.c_str());
 183       }
 184    }
 185    return true;
 186 }
 187                                                                         /*}}}*/