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Xen Summit Tokyo 2008
 マスタ サブタイトルの書式設定

 Takahiro Shinagawa
 University of Tsukuba

 Introduction to BitVisor and
 Comparison with Xen


2008/11/21      Xen Summit Tokyo 2008
What is BitVisor ?
    A VMM featuring security functionalities


     Has been developed by “Secure VM Project”
          A R&D project with governmental support
      ▪

              Initiated by NISC (National Information Security Center)
          ▪



              Funded by SCF of MEXT
          ▪



                  SCF: Special Coordination Funds for Promoting Science and Technology
              


                  MEXT: Ministry of education, culture, sports, science and technology
              




     developed from scratch (an all-Japanese product)
         Several universities and organizations are involved
      ▪
                                            * VMM: Virtual Machine
2008/11/21         Xen Summit Tokyo 2008                      22
                                            Monitor
Background & Purpose
    Increasing threats of information leakage


     From lost or stolen PCs and USB memories
     Through the Internet
          Via viruses and P2P file-sharing software
      ▪




    Using a VMM to prevent information leakage


     Enforce encryption and authentication
          Encrypt storages and networks
      ▪

      ▪ Authenticate with smart cards
2008/11/21       Xen Summit Tokyo 2008                33
Functions of the BitVisor

    Storage management                                    Guest OS


     Encryption of HDDs
      and USB memories                                     VMM
                                          Storage             ID                Network
                                        management        management           management

                                         Encryptio           Auth &               VPN
                                            n                 Keys


    ID management
                                                          VMM core
                                                     Hardware Virtualization


     Key & ID management
                                                          Hardware
      using smart cards


2008/11/21      Xen Summit Tokyo 2008                                                   44
Assumptions behind Design
Decisions
    Security of the VMM itself is important


     VMM should be kept as small as possible



    Used in desktop environments


     Windows is the target OS to be secured



    Limited development cost & period


     3 years, 5 full-time researchers, limited budget
2008/11/21      Xen Summit Tokyo 2008                    55
Para Pass-through Architecture
    Pass-through most I/Os

                                                             Guest OS
     Guest handles the devices                             Device Driver


          Devices are not virtualized
      ▪
                                                Para pass-through VMM
                                                  Parapass-through driver

    Intercept partial I/Os                  Control I/Os    Other I/Os      Data I/Os

                                                           Pass-through
                                               Access                       Encryption
                                               Control
     Control I/Os are monitored                            Hardware
                                                              Device
          for access control
      ▪

     Data I/Os are converted
      ▪ for   encryption
                                                                                 66
2008/11/21          Xen Summit Tokyo 2008
Advantages
    The VMM becomes small


     CPU & memory virtualization is simplified
          No scheduling and protection among VMs
      ▪

     Drivers are simplified
          Need to handle only control I/Os and data I/Os
      ▪




    Overhead becomes lower


     Pass-through most I/Os
      ▪ Even   Windows Vista Aero will work
2008/11/21         Xen Summit Tokyo 2008                   77
Disadvantages
    Multiple OSes cannot run simultaneously


     The guest OS directly handles the devices
-> Acceptable since the target is desktop computers


    Hardware support is limited


     A driver is required for each (monitored) device
-> Acceptable in office (government) environments


2008/11/21      Xen Summit Tokyo 2008                    88
Comparison with other VMMs
    Type II VMM
                                                    Guest OS      Guest OS
                                                             VMM
                                                          Device Model

     TCB = Host OS + VMM
                                                            Host OS
                                                          Device Driver
          Ex. Linux(56M LOC)+QEMU(310K LOC)
      ▪
                                                           hardware




                                                     Guest OS      Guest OS
                                                             VMM
                                                          Device Model

    Type I VMM

                                                          Device Driver


     VMM has device model and drivers                     hardware



          Ex. VMWare ESX hypervisor has 200K LOC
      ▪

                                                   * LOC: Lines Of
                                                   Code
2008/11/21         Xen Summit Tokyo 2008                        99
Comparison with Xen (Size)
    Xen

                                                                      Guest
                                                     Domain 0

     VMM (hypervisor) is relatively small                             OS
                                                       Device
                                                       Model
                                                    Device Driver

          About 100 K LOC [Murray et al. VEE2008]
      ▪                                                      VMM
                                                           hardware

     TCB is not necesssarily small
          Including Domain 0
      ▪




    BitVisor


     VMM is small
      ▪ VMM    core has about 20 K LOC
2008/11/21         Xen Summit Tokyo 2008                                  1010
Comparison with Xen (Overhead)
                           Xen               BitVisor
Need scheduling among      Yes               No
VMs                        (support multiple (support only
                           VMs)              single VM)
Need shadow paging         Yes              Yes
                           (for address     (for protection of
                           translation and  the VMM)
                           protection among
                           VMs and the
                           VMM)
- Shadow paging            Optimized         Preliminary
implementation                               (EPT/NPT will help)
Device driver              Para-             Parapass-through
2008/11/21        Xen Summit Tokyo 2008                      1111
Experimental Setup
    Hardware


     Intel Core 2 Duo E8600 (3.33GHz)
     4GB memory
     10,000rpm HDD
          (Western Digital Raptor WD740GD)
      ▪




    Software


     VMM: BitVisor 0.3 (64bit)
    Guest    OS: Fedora 9Tokyo 2008 Windows Vista (64bit)
                  Xen Summit (64bit),
2008/11/21                                               1212
Experimental Result 1
                   Now Printing




2008/11/21   Xen Summit Tokyo 2008   1313
Experimental Result 2
                   Now Printing




2008/11/21   Xen Summit Tokyo 2008   1414
Summary
    A Secure VMM called BitVisor was introduced


     Encryption of storages and networks
     Authentication and key management using smart
      cards


    Comparisons with Xen were presented


     Difference in the architectures
          Para-virtualization v.s. Para-passthrough
      ▪

     Difference in the performances
2008/11/21          Xen Summit Tokyo 2008             1515
Current Status
    BitVisor 0.7 has been (will be) released


     Intel VT, 32/64bit, and SMP/Multicore
          Also AMD SVM (single processor only)
      ▪

     Major operating systems are supported
          Windows Vista/XP, Linux, FreeBSD, ...
      ▪

     HDD encryption (ATA only)
     USB memory encryption (UHCI only)
     Type B smart cards
     IPsec VPN (Intel PRO100 only)
2008/11/21      Xen Summit Tokyo 2008             1616
Download




     http://www.securevm.org/



2008/11/21   Xen Summit Tokyo 2008   1717

More Related Content

XS Japan 2008 BitVisor English

  • 1. Xen Summit Tokyo 2008 マスタ サブタイトルの書式設定 Takahiro Shinagawa University of Tsukuba Introduction to BitVisor and Comparison with Xen 2008/11/21 Xen Summit Tokyo 2008
  • 2. What is BitVisor ? A VMM featuring security functionalities   Has been developed by “Secure VM Project” A R&D project with governmental support ▪ Initiated by NISC (National Information Security Center) ▪ Funded by SCF of MEXT ▪ SCF: Special Coordination Funds for Promoting Science and Technology  MEXT: Ministry of education, culture, sports, science and technology   developed from scratch (an all-Japanese product) Several universities and organizations are involved ▪ * VMM: Virtual Machine 2008/11/21 Xen Summit Tokyo 2008 22 Monitor
  • 3. Background & Purpose Increasing threats of information leakage   From lost or stolen PCs and USB memories  Through the Internet Via viruses and P2P file-sharing software ▪ Using a VMM to prevent information leakage   Enforce encryption and authentication Encrypt storages and networks ▪ ▪ Authenticate with smart cards 2008/11/21 Xen Summit Tokyo 2008 33
  • 4. Functions of the BitVisor Storage management Guest OS   Encryption of HDDs and USB memories VMM Storage ID Network management management management Encryptio Auth & VPN n Keys ID management  VMM core Hardware Virtualization  Key & ID management Hardware using smart cards 2008/11/21 Xen Summit Tokyo 2008 44
  • 5. Assumptions behind Design Decisions Security of the VMM itself is important   VMM should be kept as small as possible Used in desktop environments   Windows is the target OS to be secured Limited development cost & period   3 years, 5 full-time researchers, limited budget 2008/11/21 Xen Summit Tokyo 2008 55
  • 6. Para Pass-through Architecture Pass-through most I/Os  Guest OS  Guest handles the devices Device Driver Devices are not virtualized ▪ Para pass-through VMM Parapass-through driver Intercept partial I/Os Control I/Os Other I/Os Data I/Os  Pass-through Access Encryption Control  Control I/Os are monitored Hardware Device for access control ▪  Data I/Os are converted ▪ for encryption 66 2008/11/21 Xen Summit Tokyo 2008
  • 7. Advantages The VMM becomes small   CPU & memory virtualization is simplified No scheduling and protection among VMs ▪  Drivers are simplified Need to handle only control I/Os and data I/Os ▪ Overhead becomes lower   Pass-through most I/Os ▪ Even Windows Vista Aero will work 2008/11/21 Xen Summit Tokyo 2008 77
  • 8. Disadvantages Multiple OSes cannot run simultaneously   The guest OS directly handles the devices -> Acceptable since the target is desktop computers Hardware support is limited   A driver is required for each (monitored) device -> Acceptable in office (government) environments 2008/11/21 Xen Summit Tokyo 2008 88
  • 9. Comparison with other VMMs Type II VMM  Guest OS Guest OS VMM Device Model  TCB = Host OS + VMM Host OS Device Driver Ex. Linux(56M LOC)+QEMU(310K LOC) ▪ hardware Guest OS Guest OS VMM Device Model Type I VMM  Device Driver  VMM has device model and drivers hardware Ex. VMWare ESX hypervisor has 200K LOC ▪ * LOC: Lines Of Code 2008/11/21 Xen Summit Tokyo 2008 99
  • 10. Comparison with Xen (Size) Xen  Guest Domain 0  VMM (hypervisor) is relatively small OS Device Model Device Driver About 100 K LOC [Murray et al. VEE2008] ▪ VMM hardware  TCB is not necesssarily small Including Domain 0 ▪ BitVisor   VMM is small ▪ VMM core has about 20 K LOC 2008/11/21 Xen Summit Tokyo 2008 1010
  • 11. Comparison with Xen (Overhead) Xen BitVisor Need scheduling among Yes No VMs (support multiple (support only VMs) single VM) Need shadow paging Yes Yes (for address (for protection of translation and the VMM) protection among VMs and the VMM) - Shadow paging Optimized Preliminary implementation (EPT/NPT will help) Device driver Para- Parapass-through 2008/11/21 Xen Summit Tokyo 2008 1111
  • 12. Experimental Setup Hardware   Intel Core 2 Duo E8600 (3.33GHz)  4GB memory  10,000rpm HDD (Western Digital Raptor WD740GD) ▪ Software   VMM: BitVisor 0.3 (64bit)  Guest OS: Fedora 9Tokyo 2008 Windows Vista (64bit) Xen Summit (64bit), 2008/11/21 1212
  • 13. Experimental Result 1 Now Printing 2008/11/21 Xen Summit Tokyo 2008 1313
  • 14. Experimental Result 2 Now Printing 2008/11/21 Xen Summit Tokyo 2008 1414
  • 15. Summary A Secure VMM called BitVisor was introduced   Encryption of storages and networks  Authentication and key management using smart cards Comparisons with Xen were presented   Difference in the architectures Para-virtualization v.s. Para-passthrough ▪  Difference in the performances 2008/11/21 Xen Summit Tokyo 2008 1515
  • 16. Current Status BitVisor 0.7 has been (will be) released   Intel VT, 32/64bit, and SMP/Multicore Also AMD SVM (single processor only) ▪  Major operating systems are supported Windows Vista/XP, Linux, FreeBSD, ... ▪  HDD encryption (ATA only)  USB memory encryption (UHCI only)  Type B smart cards  IPsec VPN (Intel PRO100 only) 2008/11/21 Xen Summit Tokyo 2008 1616
  • 17. Download http://www.securevm.org/ 2008/11/21 Xen Summit Tokyo 2008 1717