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Casper Admin failing to compute checksums for packages

  • December 21, 2017
  • 6 replies
  • 52 views
M
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When I drag a package into Casper Admin, it no longer computes (or at least no longer stores) checksums for packages that are uploaded into it:

This is with JAMF Pro v9.101.0. There's nothing in the release notes for that version about a known problem with computing checksums.

Computer Management --> Security --> Package Validation is set to "Never". Any other setting results in a verification failure.

I can't find any relevant error messages in /var/log/jamf.log or /var/log/system.log.

Any ideas?

Best answer by mthakur

Fixed. It was a file permissions issue.

It seems Casper Admin chooses one of /sbin/md5 or /usr/bin/shasum to calculate checksums.

Checking the executable immediately identified the problem:

$ ls -l /usr/bin/shasum -rw-rw-rw- 37 root wheel 811 Sep 9 2014 /usr/bin/shasum $

The fix was to restore execute permissions to this ... um... executable:

$ sudo chmod 755 /usr/bin/shasum Password: $ ls -l /usr/bin/shasum -rwxr-xr-x 37 root wheel 811 Sep 9 2014 /usr/bin/shasum $

Voila! A quick test in Casper Admin shows the checksums are once again being computed and stored, but with a twist: Checksums are now SHA-512 hashes, not MD5 or SHA-1 or whatever was being used before.

Unresolved: Why did /usr/bin/shasum on my Mac admin machine a) lose its execute permissions and b) become world writable?
Possible answer: The /usr/bin/shasum "executable" is actually a perl script, and its file permissions may have been inadvertently modified when I downloaded and installed some perl libraries.

Curious: What logic does Casper Admin use to choose whether to compute checksums using MD5, SHA1, or SHA512 hashes?
Possible answer: I'm guessing it's related at least in part to the JAMF Pro and macOS versions (I'm running v9.101.0 on Yosemite), but that may not be the full story.

Anyway, thanks to all to read or responded. Happy holidays!

    6 replies

    C
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    • cddwyer
    • Contributor
    • December 22, 2017

    Isn't it better to deploy Mac App Store Apps likes Xcode through VPP?

    justin_smith
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    • justin_smith
    • New Contributor
    • December 22, 2017

    When this happens for me I can usually right click on the file(s) and calculate checksum. If it fails, I rename the file (not the display name, the actual file name) to something slightly different and try calculating it again.

    M
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    • mthakur
    • Author
    • Valued Contributor
    • December 28, 2017

    @cddwyer Sure, VPP would be good, but I can't use it (yet) because of internal bureaucracy at my organization.

    M
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    • mthakur
    • Author
    • Valued Contributor
    • December 28, 2017

    @justinssmith I had already tried Casper Admin --> right click on package --> Calculate Selected Packages Checksum. Noworkee...
    I tried renaming the file, and ... still noworkee.

    Thanks anyway for the suggestions.

    M
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    • mthakur
    • Author
    • Valued Contributor
    • Answer
    • December 28, 2017

    Fixed. It was a file permissions issue.

    It seems Casper Admin chooses one of /sbin/md5 or /usr/bin/shasum to calculate checksums.

    Checking the executable immediately identified the problem:

    $ ls -l /usr/bin/shasum -rw-rw-rw- 37 root wheel 811 Sep 9 2014 /usr/bin/shasum $

    The fix was to restore execute permissions to this ... um... executable:

    $ sudo chmod 755 /usr/bin/shasum Password: $ ls -l /usr/bin/shasum -rwxr-xr-x 37 root wheel 811 Sep 9 2014 /usr/bin/shasum $

    Voila! A quick test in Casper Admin shows the checksums are once again being computed and stored, but with a twist: Checksums are now SHA-512 hashes, not MD5 or SHA-1 or whatever was being used before.

    Unresolved: Why did /usr/bin/shasum on my Mac admin machine a) lose its execute permissions and b) become world writable?
    Possible answer: The /usr/bin/shasum "executable" is actually a perl script, and its file permissions may have been inadvertently modified when I downloaded and installed some perl libraries.

    Curious: What logic does Casper Admin use to choose whether to compute checksums using MD5, SHA1, or SHA512 hashes?
    Possible answer: I'm guessing it's related at least in part to the JAMF Pro and macOS versions (I'm running v9.101.0 on Yosemite), but that may not be the full story.

    Anyway, thanks to all to read or responded. Happy holidays!

    S
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    • scottmorabito
    • New Contributor
    • October 21, 2019

    Not the same issues as op but confirmed having an apostrophe in package name causes checksum failure only when using JAMF Admin. JAMF 10.15.1. Web upload if using cloud works fine.

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