Commit graph

13 commits

Author SHA1 Message Date
David Gibson
527c822a3b test/nstool: Provide useful error if given a path that's too long
Normal filesystem paths can be very long (PATH_MAX is around 8k), however
Unix domain sockets can only use relatively short paths (UNIX_PATH_MAX is
108 on Linux).  Currently nstool will simply truncate paths that are too
long, leading to difficult to understand failures.

Make such failures clearer, with an explicit error message if given a path
that's too long.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-05-23 17:06:29 +02:00
David Gibson
1a3ade9037 nstool: Enter holder's cwd when changing mount ns with nstool exec
If we enter a mount namespace with nstool exec our working directory will
be changed to / in the new mount ns.  This is surprising if we haven't
actually altered any mounts yet in the new ns.  Instead, change the working
directory to match that of the holder process in this situation.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:12:12 +02:00
David Gibson
98031bee73 nstool: Advertise the holder's cwd (in its mountns) across the socket
This is possible useful in nstool info and has further uses for nstool
exec.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:12:10 +02:00
David Gibson
329149d51a nstool: Add --keep-caps option to nstool exec
This allows you to run commands within a user namespace with the
privilege that comes from owning that userns.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:12:03 +02:00
David Gibson
0b66944648 nstool: Add nstool exec command to execute commands in an nstool namespace
This combines nstool info -pw <sock> with nsenter with various options for
a more convenient and less verbose of entering existing nstool managed
namespaces.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:12:01 +02:00
David Gibson
3bcbca5db8 nstool: Helpers to iterate through namespace types
Will make things a bit less verbose in future.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:11:59 +02:00
David Gibson
f6a9ea3af5 nstool: Add magic number to advertized information
So that we'll probably give a better error if you point it at something
that's not an nstool hold control socket.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:11:57 +02:00
David Gibson
4311066bdb nstool: Detect what namespaces target is in
Give nstool the ability to detect what namespaces the target process is in,
relative to where it's called.  That is, those namespace types for which
the target is not in the same namespace as the caller.  For now, just
print this information with "info", which can be useful for debugging.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:11:55 +02:00
David Gibson
fd4a752e92 nstool: Replace "pid" subcommand with "info" subcommand
The new subcommand gives more information about the holder process and its
namespace, and may be further extended in future.  Add some options which
give the old behaviour for existing scripts.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:11:52 +02:00
David Gibson
a4b017d91c nstool: Split some command line parsing and socket setup to subcommands
This will make it easier to differentiate the options to those commands
further in future.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:11:50 +02:00
David Gibson
42fb218347 nstool: Move description of its operation modes from comment to usage
Easier to see it there.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:11:48 +02:00
David Gibson
2884ccd2e7 nstool: Reverse parameters to nstool
Having the "subcommand" first is more conventional and will make it more
natural for future extensions I have planned.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:11:43 +02:00
David Gibson
4914fce77b nstool: Rename nsholder to nstool
In preparation for extending what it does.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-08 01:11:41 +02:00
Renamed from test/nsholder.c (Browse further)