PosixPathSecurity.cpp

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#include "blocxx/BLOCXX_config.h"
#include "blocxx/PathSecurity.hpp"

namespace BLOCXX_NAMESPACE
{

   inline bool group_ok(::gid_t gid)
   {
#ifdef BLOCXX_SOLARIS
      return gid == 0 /* root */ || gid == 3 /* sys */;
#elif defined(BLOCXX_DARWIN)
      return gid == 0 /* root */ || gid == 80 /* admin */;
#else
      return gid == 0 /* root */;
#endif
   }

   inline bool check_grp_oth(struct stat const & x)
   {
      ::mode_t badmsk = group_ok(x.st_gid) ? S_IWOTH : (S_IWGRP | S_IWOTH);
      return !(x.st_mode & badmsk);
   }

   EFileStatusReturn file_ok(struct stat const & x, ::uid_t uid, bool full_path)
   {
      // Note: originally this disallowed multiple hard links to a file,
      // but that restriction is not necessary, as the permissions for a
      // file are associated with its inode, and not with its directory
      // entries.  Note also that it's not a problem if someone does an
      // unlink of an alternate path to the file, as this just removes
      // the alternate directory entry -- the file itself is not actually
      // deleted until there are no hard links at all to it.
      EFileStatusReturn retval(E_FILE_OK);
      if (x.st_uid == 0 || 
#if defined(BLOCXX_HPUX) || defined(BLOCXX_AIX)
          // on HP-UX & AIX, many system dirs & files are owned by the bin user, which has a uid of 2.
          x.st_uid == 2 ||
#endif
          x.st_uid == uid)
      {
         if (!(S_ISLNK(x.st_mode) || check_grp_oth(x) || S_ISDIR(x.st_mode) && !full_path && (x.st_mode & S_ISVTX)))
         {
            retval = E_FILE_BAD_OTHER;
         }
      }
      else
      {
         retval = E_FILE_BAD_OWNER;
      }
      return retval;
   }

   EFileStatusReturn getFileStatus(struct stat const & x, uid_t uid, bool is_full_path, const String& path)
   {
      return file_ok(x, uid, is_full_path);
   }

   bool isPathAbsolute(String const & path)
   {
      return path.startsWith("/") ? true : false;
   }

}  // end namespace BLOCXX_NAMESPACE