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Telnet 3270

  • TN3270
  • open source client
  • x3270
  • in clear text encrypted with epsidic
  • Free
  • provides easy screen recording

SNA

  • System Network Architecture
  • Networks before TCP/IP
  • Logical Units gets an ID
  • Identified in the network
    • Typically your terminal gets a LU / Logical Unit

VTAM

  • When we connect it is likely the first screen

Commands

  1. LOGON
      • LOGON APPLID(TSO) DATA(ROOT)
  2. LOGOFF
  3. IBMTEST
    1. IBMECHO A ... 9

TSO

  • Time sharing option
    • Shell environment
    • used to be optional
  • The "BASH" shell of z/OS
  • Lot's of commands we can run
  • You 'CALL' executables
  • You 'EXEC' REXX scripts

REXX

  • Restructured Extender Executor
  • Scripting Language
  • Preinstalled on all z/OS

JCL

  • Job Control Language
  • looks like garbage
  • You 'SUBmit' jobs
  • Useful to do stuff where you can submit JCL but don't have an interactive terminal

RACF'd

  • Resource Access Control Facility
    • IBM security Product
  • Think 'Active Directory' but for your mainframe
  • Could also be:
    • CA-TopSecret
    • CA-ACF2
  • Most important rights (aka attributes)
    • SPECIAL
      • Make any change to RACF
      • Can't do anything but can give myself the ability to do anything
      • Have the ability to sudo root, if they type the right command
    • OPERATIONS
      • Edit any file

Virtual Storage

  • Memory
  • Lot's of important stuff in memory

APF

  • Authorized Program Facility
  • Think 'programs with setuid 0'
  • Except, it's not access rights
  • APF programs can edit ANY region of memory
  • RACF, when you log in takes your access rights from the database and puts into a place in memory that is write protected. You as a normal user cannot change it.
  • and references that instead of it's DB
  • Both SPECIAL and OPERATIONS are one bit flags in your ACEE.
  • If we can change our memory than we give ourselves access to whatever we want.
  • If we can change these 2 bits then we can own the mainframe.

CICS

  • Customer Information Control System
  • Websites before websites existed
  • Transaction IDs = URL
    • But they are only 4 characters long
    • I.E. CESN, CSGM, CEDA