apt/apt-private/private-download.cc

// Include Files							/*{{{*/
#include <config.h>

#include <apt-pkg/acquire.h>
#include <apt-pkg/acquire-item.h>
#include <apt-pkg/configuration.h>
#include <apt-pkg/error.h>
#include <apt-pkg/fileutl.h>
#include <apt-pkg/strutl.h>

#include <apt-private/private-output.h>
#include <apt-private/private-download.h>

#include <fstream>
#include <string>
#include <vector>

#include <unistd.h>
#include <sys/types.h>
#include <pwd.h>
#include <fcntl.h>
#include <sys/vfs.h>
#include <sys/statvfs.h>
#include <errno.h>

#include <apti18n.h>
									/*}}}*/

bool CheckDropPrivsMustBeDisabled(pkgAcquire &Fetcher)			/*{{{*/
{
   // no need/possibility to drop privs
   if(getuid() != 0)
      return true;

   // the user does not want to drop privs
   std::string SandboxUser = _config->Find("APT::Sandbox::User");
   if (SandboxUser.empty())
      return true;

   struct passwd const * const pw = getpwnam(SandboxUser.c_str());
   if (pw == NULL)
      return true;

   if (seteuid(pw->pw_uid) != 0)
      return _error->Errno("seteuid", "seteuid %u failed", pw->pw_uid);

   bool res = true;
   // check if we can write to destfile
   for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin();
	I != Fetcher.ItemsEnd() && res == true; ++I)
   {
      if ((*I)->DestFile.empty())
	 continue;
      // we assume that an existing (partial) file means that we have sufficient rights
      if (RealFileExists((*I)->DestFile))
	 continue;
      int fd = open((*I)->DestFile.c_str(), O_CREAT | O_EXCL | O_RDWR, 0600);
      if (fd < 0)
      {
	 res = false;
	 std::string msg;
	 strprintf(msg, _("Can't drop privileges for downloading as file '%s' couldn't be accessed by user '%s'."),
	       (*I)->DestFile.c_str(), SandboxUser.c_str());
	 std::cerr << "W: " << msg << std::endl;
	 _config->Set("APT::Sandbox::User", "");
	 break;
      }
      unlink((*I)->DestFile.c_str());
      close(fd);
   }

   if (seteuid(0) != 0)
      return _error->Errno("seteuid", "seteuid %u failed", 0);

   return res;
}
									/*}}}*/
// CheckAuth - check if each download comes form a trusted source	/*{{{*/
bool CheckAuth(pkgAcquire& Fetcher, bool const PromptUser)
{
   std::string UntrustedList;
   for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin(); I < Fetcher.ItemsEnd(); ++I)
      if (!(*I)->IsTrusted())
          UntrustedList += std::string((*I)->ShortDesc()) + " ";

   if (UntrustedList == "")
      return true;

   return AuthPrompt(UntrustedList, PromptUser);
}

bool AuthPrompt(std::string const &UntrustedList, bool const PromptUser)
{
   ShowList(c2out,_("WARNING: The following packages cannot be authenticated!"),UntrustedList,"");

   if (_config->FindB("APT::Get::AllowUnauthenticated",false) == true)
   {
      c2out << _("Authentication warning overridden.\n");
      return true;
   }

   if (PromptUser == false)
      return _error->Error(_("Some packages could not be authenticated"));

   if (_config->FindI("quiet",0) < 2
       && _config->FindB("APT::Get::Assume-Yes",false) == false)
   {
      c2out << _("Install these packages without verification?") << std::flush;
      if (!YnPrompt(false))
         return _error->Error(_("Some packages could not be authenticated"));

      return true;
   }
   else if (_config->FindB("APT::Get::Force-Yes",false) == true)
      return true;

   return _error->Error(_("There are problems and -y was used without --force-yes"));
}
									/*}}}*/
bool AcquireRun(pkgAcquire &Fetcher, int const PulseInterval, bool * const Failure, bool * const TransientNetworkFailure)/*{{{*/
{
   pkgAcquire::RunResult res;
   if(PulseInterval > 0)
      res = Fetcher.Run(PulseInterval);
   else
      res = Fetcher.Run();

   if (res == pkgAcquire::Failed)
      return false;

   for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin();
	I != Fetcher.ItemsEnd(); ++I)
   {

      if ((*I)->Status == pkgAcquire::Item::StatDone &&
	    (*I)->Complete == true)
	 continue;

      if (TransientNetworkFailure != NULL && (*I)->Status == pkgAcquire::Item::StatIdle)
      {
	 *TransientNetworkFailure = true;
	 continue;
      }

      ::URI uri((*I)->DescURI());
      uri.User.clear();
      uri.Password.clear();
      std::string descUri = std::string(uri);
      _error->Error(_("Failed to fetch %s  %s\n"), descUri.c_str(),
	    (*I)->ErrorText.c_str());

      if (Failure != NULL)
	 *Failure = true;
   }

   return true;
}
									/*}}}*/
bool CheckFreeSpaceBeforeDownload(std::string const &Dir, unsigned long long FetchBytes)/*{{{*/
{
   uint32_t const RAMFS_MAGIC = 0x858458f6;
   /* Check for enough free space, but only if we are actually going to
      download */
   if (_config->FindB("APT::Get::Print-URIs", false) == true ||
       _config->FindB("APT::Get::Download", true) == false)
      return true;

   struct statvfs Buf;
   if (statvfs(Dir.c_str(),&Buf) != 0) {
      if (errno == EOVERFLOW)
	 return _error->WarningE("statvfs",_("Couldn't determine free space in %s"),
	       Dir.c_str());
      else
	 return _error->Errno("statvfs",_("Couldn't determine free space in %s"),
	       Dir.c_str());
   }
   else
   {
      unsigned long long const FreeBlocks = _config->Find("APT::Sandbox::User").empty() ? Buf.f_bfree : Buf.f_bavail;
      if (FreeBlocks < (FetchBytes / Buf.f_bsize))
      {
	 struct statfs Stat;
	 if (statfs(Dir.c_str(),&Stat) != 0
#if HAVE_STRUCT_STATFS_F_TYPE
	       || Stat.f_type != RAMFS_MAGIC
#endif
	    )
	    return _error->Error(_("You don't have enough free space in %s."),
		  Dir.c_str());
      }
   }
   return true;
}
									/*}}}*/