4 ms·

?! Are you missing the part where OS X is based on BSD?

ori_b 16y ago
That's a myth. There are some parts like libc and the command line apps that were ported from BSD, the the kernel is a mach-that-isn't-anymore hybrid oddity, and the user interface is an Apple-only system. So, to a good approximation, you can say that the command line is based on BSD, and the rest came from NeXT and Apple, with a bit of GNU mixed in. The BSD heritage is rather insignificant when it comes to security, since the largest attack surface comes from Apple applications like Safari, or the file manager, or other apps the end user uses directly on a regular basis.
- pavs 16y ago
  Mac OS X Leopard receives UNIX 03 certification: http://arstechnica.com/apple/news/2007/08/mac-os-x-leopard-receives-unix-03-certification.ars http://arstechnica.com/apple/news/2007/08/mac-os-x-leopard-r...
  - ori_b 16y ago
    Sure, but that just means it provides the correct library calls, has the right shell utilities, and so on. It says nothing about the pedigree, or the amount of security. It's undoubtedly a good thing, but it's not important in this context.
    - pavs 16y ago
      Where do you draw the line when a BSD based OS has been customized to the extend that it can't be considered a BSD based OS?
      - sp332 16y ago
        That only describes the interface, not the implementation. It says (almost) nothing about the kernel, or security.
        pavs 16y ago
        You are right. I just double checked my facts and OSX kernel is actually a hybrid kernel and not a direct descendant of BSD flavor (which was my impression). My mistake.
  - sp332 16y ago
    That's like saying Windows is UNIX-based because it conforms to POSIX.1.
    - abrahamsen 16y ago
      That would be like calling someone a Ph.D. after completing kindergarten. UNIX 03 certification means MacOS X is a UNIX. It doesn't say anything about its status as a BSD though.
- tptacek 16y ago
  xnu's BSD code isn't a myth. Have you ever actually read any of it? Which parts? I had to dive into it headfirst for a Black Hat presentation in 2007, in which we loaded probes into a running xnu kernel to detect hypervisors. I was surprised by how easy it was to navigate based on my familiarity with FreeBSD's kernel. Obviously, there's quite a bit of non-BSD code in OS X, but for anyone who has worked with a BSD kernel before, the similarities are impossible to miss. Hell, even if you can't read kernel code, the fact that OS X has sysctl, doesn't have proc, and debugs with ptrace() doesn't tell you anything?

ori_b 16y ago

That's a myth. There are some parts like libc and the command line apps that were ported from BSD, the the kernel is a mach-that-isn't-anymore hybrid oddity, and the user interface is an Apple-only system. So, to a good approximation, you can say that the command line is based on BSD, and the rest came from NeXT and Apple, with a bit of GNU mixed in. The BSD heritage is rather insignificant when it comes to security, since the largest attack surface comes from Apple applications like Safari, or the file manager, or other apps the end user uses directly on a regular basis.

pavs 16y ago
Mac OS X Leopard receives UNIX 03 certification: http://arstechnica.com/apple/news/2007/08/mac-os-x-leopard-receives-unix-03-certification.ars http://arstechnica.com/apple/news/2007/08/mac-os-x-leopard-r...
- ori_b 16y ago
  Sure, but that just means it provides the correct library calls, has the right shell utilities, and so on. It says nothing about the pedigree, or the amount of security. It's undoubtedly a good thing, but it's not important in this context.
  - pavs 16y ago
    Where do you draw the line when a BSD based OS has been customized to the extend that it can't be considered a BSD based OS?
    - sp332 16y ago
      That only describes the interface, not the implementation. It says (almost) nothing about the kernel, or security.
      - pavs 16y ago
        You are right. I just double checked my facts and OSX kernel is actually a hybrid kernel and not a direct descendant of BSD flavor (which was my impression). My mistake.
- sp332 16y ago
  That's like saying Windows is UNIX-based because it conforms to POSIX.1.
  - abrahamsen 16y ago
    That would be like calling someone a Ph.D. after completing kindergarten. UNIX 03 certification means MacOS X is a UNIX. It doesn't say anything about its status as a BSD though.
tptacek 16y ago
xnu's BSD code isn't a myth. Have you ever actually read any of it? Which parts? I had to dive into it headfirst for a Black Hat presentation in 2007, in which we loaded probes into a running xnu kernel to detect hypervisors. I was surprised by how easy it was to navigate based on my familiarity with FreeBSD's kernel. Obviously, there's quite a bit of non-BSD code in OS X, but for anyone who has worked with a BSD kernel before, the similarities are impossible to miss. Hell, even if you can't read kernel code, the fact that OS X has sysctl, doesn't have proc, and debugs with ptrace() doesn't tell you anything?