8170762: Document that ISO10126Padding pads with random bytes

[driverkt]

JDK-8170762 - update Javadoc to indicate ISO10126Padding pads with random bytes, though the spec does not require random bytes

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Issue

• JDK-8170762: Document that ISO10126Padding pads with random bytes

Reviewers

• Weijun Wang (@wangweij - Reviewer)

Reviewing

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[openjdk]

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[driverkt]

/issue add 8170762

[openjdk]

@driverkt This issue is referenced in the PR title - it will now be updated.

[mlbridge]

Webrevs

• 00: Full (be4f321a)

[wangweij]

Bug reporter says "document it in the SunJCE documentation". I am not sure what "SunJCE documentation" is, but the file updated here is an internal class and not a part of any documentation. The best suggestion I can make is adding a footnote to the padding name in Table 4-16 in https://docs.oracle.com/en/java/javase/18/security/oracle-providers.html.

[wangweij]

Also, the bug title does not match code change. Randomness is not removed, it's documented.

[driverkt]

@wangweij - thanks for clarifying! I was wondering about both of these items.

Maybe you can point me in the right direction for updating the documentation link you provided? Is it available in the open?

WRT the bug, should I just change the title of the bug, or what do you suggest?

[driverkt]

/issue add 8170762

[openjdk]

@driverkt This issue is referenced in the PR title - it will now be updated.

[wangweij]

Approved. File another docs bug to update the doc.

[openjdk]

@driverkt This change now passes all automated pre-integration checks.

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8170762: Document that ISO10126Padding pads with random bytes

Reviewed-by: weijun

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At the time when this comment was updated there had been 1 new commit pushed to the master branch:

• e291a67: 8289584: (fs) Print size values in java/nio/file/FileStore/Basic.java when they differ by > 1GiB

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[driverkt]

Filed: https://bugs.openjdk.org/browse/JDK-8289602

Approved. File another docs bug to update the doc.

[driverkt]

/integrate

[openjdk]

@driverkt
Your change (at version be4f321) is now ready to be sponsored by a Committer.

[wangweij]

/sponsor

[openjdk]

Going to push as commit 2dd00f5.
Since your change was applied there has been 1 commit pushed to the master branch:

• e291a67: 8289584: (fs) Print size values in java/nio/file/FileStore/Basic.java when they differ by > 1GiB

Your commit was automatically rebased without conflicts.

[openjdk]

@wangweij @driverkt Pushed as commit 2dd00f5.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[bradfordwetmore]

Just a comment, I believe both approaches are ok. The ISO 10126 spec says:

When padding with octets...the first subfield (pad fill) shall consist
of 0 to 7 octets with arbitrary contents.

Adam's original comment was that because the spec says "arbitrary data," we could potentially just optimize the code a small bit by not having to fill with random data, and rather just leave as an uninitialized field. But using random data to get some arbitrary data it is possibly a little safer since it will perturb the output a little vs. using an all zero padding.

So, fine to leave has been fixed. However, I do have further comments on the doc bug.

[driverkt]

Yes, @bradfordwetmore. Agreed. Both approaches are valid; hence just taking the "document the choice" approach.