Introduce a new option "size" to configure the maximum size of the
user namespace configured by keep-id.
Closes: https://github.com/containers/podman/issues/24837
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Cut is a cleaner & more performant api relative to SplitN(_, _, 2) added in go 1.18
Previously applied this refactoring to buildah:
https://github.com/containers/buildah/pull/5239
Signed-off-by: Philip Dubé <philip@peerdb.io>
Conceptually equivalent to networking by means of slirp4netns(1),
with a few practical differences:
- pasta(1) forks to background once networking is configured in the
namespace and quits on its own once the namespace is deleted:
file descriptor synchronisation and PID tracking are not needed
- port forwarding is configured via command line options at start-up,
instead of an API socket: this is taken care of right away as we're
about to start pasta
- there's no need for further selection of port forwarding modes:
pasta behaves similarly to containers-rootlessport for local binds
(splice() instead of read()/write() pairs, without L2-L4
translation), and keeps the original source address for non-local
connections like slirp4netns does
- IPv6 is not an experimental feature, and enabled by default. IPv6
port forwarding is supported
- by default, addresses and routes are copied from the host, that is,
container users will see the same IP address and routes as if they
were in the init namespace context. The interface name is also
sourced from the host upstream interface with the first default
route in the routing table. This is also configurable as documented
- sandboxing and seccomp(2) policies cannot be disabled
- only rootless mode is supported.
See https://passt.top for more details about pasta.
Also add a link to the maintained build of pasta(1) manual as valid
in the man page cross-reference checks: that's where the man page
for the latest build actually is -- it's not on Github and it doesn't
match any existing pattern, so add it explicitly.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
add two new options to the keep-id user namespace option:
- uid: allow to override the UID used inside the container.
- gid: allow to override the GID used inside the container.
For example, the following command will map the rootless user (that
has UID=0 inside the rootless user namespace) to the UID=11 inside the
container user namespace:
$ podman run --userns=keep-id:uid=11 --rm -ti fedora cat /proc/self/uid_map
0 1 11
11 0 1
12 12 65525
Closes: https://github.com/containers/podman/issues/15294
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
* Replace "setup", "lookup", "cleanup", "backup" with
"set up", "look up", "clean up", "back up"
when used as verbs. Replace also variations of those.
* Improve language in a few places.
Signed-off-by: Erik Sjölund <erik.sjolund@gmail.com>
The linter ensures a common code style.
- use switch/case instead of else if
- use if instead of switch/case for single case statement
- add space between comment and text
- detect the use of defer with os.Exit()
- use short form var += "..." instead of var = var + "..."
- detect problems with append()
```
newSlice := append(orgSlice, val)
```
This could lead to nasty bugs because the orgSlice will be changed in
place if it has enough capacity too hold the new elements. Thus we
newSlice might not be a copy.
Of course most of the changes are just cosmetic and do not cause any
logic errors but I think it is a good idea to enforce a common style.
This should help maintainability.
Signed-off-by: Paul Holzinger <pholzing@redhat.com>
From a security point of view, it would be nice to be able to map a
rootless usernamespace that does not use your own UID within the
container.
This would add protection against a hostile process escapping the
container and reading content in your homedir.
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
As of podman 1.8.0, because of commit da7595a, the default approach of providing
port-forwarding in rootless mode has switched (and been hard-coded) to rootlessport,
for the purpose of providing super performance. The side-effect of this switch is
source within the container to the port-forwarded service always appears to originate
from 127.0.0.1 (see issue #5138).
This commit allows a user to specify if they want to revert to the previous approach
of leveraging slirp4netns add_hostfwd() api which, although not as stellar performance,
restores usefulness of seeing incoming traffic origin IP addresses.
The change should be transparent; when not specified, rootlessport will continue to be
used, however if specifying --net slirp4netns:slirplisten the old approach will be used.
Note: the above may imply the restored port-forwarding via slirp4netns is not as
performant as the new rootlessport approach, however the figures shared in the original
commit that introduced rootlessport are as follows:
slirp4netns: 8.3 Gbps,
RootlessKit: 27.3 Gbps,
which are more than sufficient for many use cases where the origin of traffic is more
important than limits that cannot be reached due to bottlenecks elsewhere.
Signed-off-by: Aleks Mariusz <m.k@alek.cx>
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
change the default on cgroups v2 and create a new cgroup namespace.
When a cgroup namespace is used, processes inside the namespace are
only able to see cgroup paths relative to the cgroup namespace root
and not have full visibility on all the cgroups present on the
system.
The previous behaviour is maintained on a cgroups v1 host, where a
cgroup namespace is not created by default.
Closes: https://github.com/containers/libpod/issues/4363
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
If we call Container(), we expect the namespace to be prefixed with "container:".
Add this check, and refactor to use named const strings instead of string literals
Signed-off-by: Peter Hunt <pehunt@redhat.com>
allow a container to run in a new cgroup namespace.
When running in a new cgroup namespace, the current cgroup appears to
be the root, so that there is no way for the container to access
cgroups outside of its own subtree.
By default it uses --cgroup=host to keep the previous behavior.
To create a new namespace, --cgroup=private must be provided.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
it creates a namespace where the current UID:GID on the host is mapped
to the same UID:GID in the container.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
We accidentally patched this out trying to enable ns:/path/to/ns
This should restore the ability to configure nondefault CNI
networks with Podman, by ensuring that they request creation of a
network namespace.
Completely remove the WithNetNS() call when we do use an explicit
namespace from a path. We use that call to indicate that a netns
is going to be created - there should not be any question about
whether it actually does.
Fixes#2795
Signed-off-by: Matthew Heon <mheon@redhat.com>
We should be sharing cgroups namespace by default in pods
uts namespace sharing was broken in pods.
Create a new libpod/pkg/namespaces for handling of namespace fields
in containers
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
Closes: #1418
Approved by: mheon
