Support for the file system security requirements of computational E-mail systems

ABSTRACT

Computational e-mail systems, which allow mail messages to contain command scripts that automatically execute upon receipt, can be used as a basis for building a variety of collaborative applications. However, their use also presents a serious security problem because a command script from a sender may access/modify receiver's private files or execute applications on receiver's behalf. Existing solutions to the problem either severely restrict I/O capability of scripts, limiting the range of applications that can be supported over computational e-mail, or permit all I/O to scripts, potentially compromising the security of the receiver's files. Our model, called the intersection model of security, permits I/O for e-mail from trusted senders but without compromising the security of private files. We describe two implementations of our security model: an interpreter-level implementation and an operating systems-level implementation. We discuss the tradeoffs between the two implementations and suggest directions for future work.

REFERENCES

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INDEX TERMS

Primary Classification:
  D. Software
  D.4 OPERATING SYSTEMS

Additional Classification:
  D. Software
  D.4 OPERATING SYSTEMS

  H. Information Systems
  H.4 INFORMATION SYSTEMS APPLICATIONS
      H.4.3 Communications Applications
          Subjects: Electronic mail

General Terms:
Security, Theory

Keywords:
active email, collaboration technology, computational email, computer-supported cooperative work, file systems, groupware, security