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Access Control

POSIX Access Control

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Adam Doupé

Arizona State University

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https://pwn.college

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POSIX ACL

  • 12 permission bits for each file, logically grouped into 4 sets of three bits each

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  • first 3 bits:
    • SUID SGID Sticky-bit
  • next 3 bit sets apply to file’s owner, users in file’s group and all users respectively
    • read write execute

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POSIX ACL

  • SUID
  • SGID
  • Sticky-bit
  • read
  • write
  • execute

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