rc.d for auto-loading zfs keys
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Authored by ltning-freebsd_anduin.net on Apr 27 2021, 6:55 PM.

Details

Reviewers

allanjude
freqlabs
dteske
chuck
kevans

Group Reviewers

ZFS

Commits

rGe81b2348d210: Add zfskeys rc.d script for auto-loading encryption keys
rG33ff39796ffe: Add zfskeys rc.d script for auto-loading encryption keys

Summary

ZFS in 13 supports encryption, but for the use case where keys are
available in plaintext on disk there is no mechanism for automatically
loading keys on startup.

This script will, by default, look for any dataset with encryption and
keylocation prefixed with file://. It will attempt to unlock, timing
out after 10 seconds for each dataset found.
User can optionally specify explicitly which datasets to attempt to
unlock.

Also supports (optionally by force) unmounting filesystems and unloading
associated keys.

Diff Detail

Repository

rS FreeBSD src repository - subversion

Lint

Lint Passed

Unit

No Test Coverage

Build Status

Buildable 39803
Build 36692: arc lint + arc unit

Event Timeline

ltning-freebsd_anduin.net created this revision.Apr 27 2021, 6:55 PM

Herald added a subscriber: imp. · View Herald TranscriptApr 27 2021, 6:55 PM

ltning-freebsd_anduin.net requested review of this revision.Apr 27 2021, 6:55 PM

Harbormaster completed remote builds in B38894: Diff 88272.Apr 27 2021, 6:56 PM

allanjude edited the summary of this revision. (Show Details)Apr 27 2021, 6:58 PM

allanjude added a reviewer: dteske.Apr 28 2021, 2:23 PM

allanjude added a reviewer: chuck.

grahamperrin added a subscriber: grahamperrin.May 8 2021, 9:19 AM

dteske requested changes to this revision.May 10 2021, 7:47 PM

dteske added inline comments.

libexec/rc/rc.d/zfskeys
27–28	Current test will fail to pass a very-real (but NULL) positional argument to b64encode. Use number of arguments instead of content of arguments to determine whether to encode args or not. Combine into single statement for code efficiency (no need to test number of args if initial `shift` fails -- i.e., in the case of no args given). Also, the wrong `/bin/sh` variable is used. `"$@"` will expand to multiple positional arguments but the `%s` operator in `printf` will only take a single string. To make the two match, I suggest `"$*"` which will squish multiple positional arguments into a single string to fit into `printf`'s `%s` operator.
28	Current test will fail to pass a very-real (but NULL) positional argument to b64encode. Use number of arguments instead of content of arguments to determine whether to encode args or not.
34	Split on pipe (reason: line >80 char)
35	Use "NOT" operator; ditch the space before semi-colon (apply globally please).
36	Split on flag (reason: line >80 char)
38	Split on flag (reason: line >80 char)
44–45	Positional arguments should be quoted.
46–47	Blank line after declarations (apply globally please).

This revision now requires changes to proceed.May 10 2021, 7:47 PM

ltning-freebsd_anduin.net marked 7 inline comments as done.May 19 2021, 5:01 PM

ltning-freebsd_anduin.net added inline comments.

libexec/rc/rc.d/zfskeys
27–28	Also, the wrong `/bin/sh` variable is used. `"$@"` will expand to multiple positional arguments but the `%s` operator in `printf` will only take a single string. To make the two match, I suggest `"$*"` which will squish multiple positional arguments into a single string to fit into `printf`'s `%s` operator. I'm a bit uncertain here; the problem I'm trying to solve is the mangling of `$@` in rc, so the real solution would be to handle an arbitrary number of arguments and concatenate those into a null-terminated string. However in this script we only ever expect to see one argument (a dataset), so perhaps saying `$1` explicitly after the `shift` is more appropriate?
36	Split on flag (reason: line >80 char) I land at 75 chars here..?

ltning-freebsd_anduin.net marked an inline comment as done.Jun 8 2021, 2:47 PM

ltning-freebsd_anduin.net added inline comments.

libexec/rc/rc.d/zfskeys
27–28	I'll be keeping the "$@" here, unless I misunderstood something: $ foofunc() { printf "%s\0" "$@" ; } $ foofunc foo bar baz \| xargs -0 -n 1 echo foo bar baz $