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Diffstat (limited to 'docs/source/markdown/podman-create.1.md')
| -rw-r--r-- | docs/source/markdown/podman-create.1.md | 111 |
1 files changed, 96 insertions, 15 deletions
diff --git a/docs/source/markdown/podman-create.1.md b/docs/source/markdown/podman-create.1.md index db9ff937b..229bb82f5 100644 --- a/docs/source/markdown/podman-create.1.md +++ b/docs/source/markdown/podman-create.1.md @@ -261,8 +261,8 @@ Note: if _host_device_ is a symbolic link then it will be resolved first. The container will only store the major and minor numbers of the host device. Note: if the user only has access rights via a group, accessing the device -from inside a rootless container will fail. The **crun**(1) runtime offers a -workaround for this by adding the option **\-\-annotation run.oci.keep_original_groups=1**. +from inside a rootless container will fail. Use the `--group-add keep-groups` +flag to pass the user's supplementary group access into the container. Podman may load kernel modules required for using the specified device. The devices that podman will load modules when necessary are: @@ -361,9 +361,17 @@ GID map for the user namespace. Using this flag will run the container with user The following example maps uids 0-2000 in the container to the uids 30000-31999 on the host and gids 0-2000 in the container to the gids 30000-31999 on the host. `--gidmap=0:30000:2000` -#### **\-\-group-add**=*group* +#### **\-\-group-add**=*group|keep-groups* -Add additional groups to run as +Add additional groups to assign to primary user running within the container process. + +- `keep-groups` is a special flag that tells Podman to keep the supplementary group access. + +Allows container to use the user's supplementary group access. If file systems or +devices are only accessible by the rootless user's group, this flag tells the OCI +runtime to pass the group access into the container. Currently only available +with the `crun` OCI runtime. Note: `keep-groups` is exclusive, you cannot add any other groups +with this flag. (Not available for remote commands) #### **\-\-health-cmd**=*"command"* | *'["command", "arg1", ...]'* @@ -634,7 +642,7 @@ Valid _mode_ values are: - **none**: no networking; - **container:**_id_: reuse another container's network stack; - **host**: use the Podman host network stack. Note: the host mode gives the container full access to local system services such as D-bus and is therefore considered insecure; -- _network-id_: connect to a user-defined network, multiple networks should be comma separated; +- _network-id_: connect to a user-defined network, multiple networks should be comma-separated; - **ns:**_path_: path to a network namespace to join; - **private**: create a new namespace for the container (default) - **slirp4netns[:OPTIONS,...]**: use **slirp4netns**(1) to create a user network stack. This is the default for rootless containers. It is possible to specify these additional options: @@ -861,6 +869,8 @@ Security Options - `label=filetype:TYPE` : Set the label file type for the container files - `label=disable` : Turn off label separation for the container +Note: Labeling can be disabled for all containers by setting label=false in the **containers.conf** (`/etc/containers/containers.conf` or `$HOME/.config/containers/containers.conf`) file. + - `mask=/path/1:/path/2` : The paths to mask separated by a colon. A masked path cannot be accessed inside the container. @@ -869,13 +879,13 @@ Security Options - `seccomp=unconfined` : Turn off seccomp confinement for the container - `seccomp=profile.json` : White listed syscalls seccomp Json file to be used as a seccomp filter +- `proc-opts=OPTIONS` : Comma-separated list of options to use for the /proc mount. More details for the + possible mount options are specified in the **proc(5)** man page. + - `unmask=ALL or /path/1:/path/2` : Paths to unmask separated by a colon. If set to **ALL**, it will unmask all the paths that are masked or made read only by default. The default masked paths are **/proc/acpi, /proc/kcore, /proc/keys, /proc/latency_stats, /proc/sched_debug, /proc/scsi, /proc/timer_list, /proc/timer_stats, /sys/firmware, and /sys/fs/selinux.** The default paths that are read only are **/proc/asound, /proc/bus, /proc/fs, /proc/irq, /proc/sys, /proc/sysrq-trigger, /sys/fs/cgroup**. -- `proc-opts=OPTIONS` : Comma separated list of options to use for the /proc mount. More details for the - possible mount options are specified at **proc(5)** man page. - Note: Labeling can be disabled for all containers by setting label=false in the **containers.conf** (`/etc/containers/containers.conf` or `$HOME/.config/containers/containers.conf`) file. #### **\-\-shm-size**=*size* @@ -975,11 +985,72 @@ Remote connections use local containers.conf for defaults Set the umask inside the container. Defaults to `0022`. Remote connections use local containers.conf for defaults -#### **\-\-uidmap**=*container_uid:host_uid:amount* +#### **\-\-uidmap**=*container_uid*:*from_uid*:*amount* + +Run the container in a new user namespace using the supplied mapping. This +option conflicts with the **\-\-userns** and **\-\-subuidname** options. This +option provides a way to map host UIDs to container UIDs. It can be passed +several times to map different ranges. + +The _from_uid_ value is based upon the user running the command, either rootful or rootless users. +* rootful user: *container_uid*:*host_uid*:*amount* +* rootless user: *container_uid*:*intermediate_uid*:*amount* + +When **podman create** is called by a privileged user, the option **\-\-uidmap** +works as a direct mapping between host UIDs and container UIDs. + +host UID -> container UID + +The _amount_ specifies the number of consecutive UIDs that will be mapped. +If for example _amount_ is **4** the mapping would look like: + +| host UID | container UID | +| - | - | +| _from_uid_ | _container_uid_ | +| _from_uid_ + 1 | _container_uid_ + 1 | +| _from_uid_ + 2 | _container_uid_ + 2 | +| _from_uid_ + 3 | _container_uid_ + 3 | + +When **podman create** is called by an unprivileged user (i.e. running rootless), +the value _from_uid_ is interpreted as an "intermediate UID". In the rootless +case, host UIDs are not mapped directly to container UIDs. Instead the mapping +happens over two mapping steps: -UID map for the user namespace. Using this flag will run the container with user namespace enabled. It conflicts with the `--userns` and `--subuidname` flags. +host UID -> intermediate UID -> container UID -The following example maps uids 0-2000 in the container to the uids 30000-31999 on the host and gids 0-2000 in the container to the gids 30000-31999 on the host. `--uidmap=0:30000:2000` +The **\-\-uidmap** option only influences the second mapping step. + +The first mapping step is derived by Podman from the contents of the file +_/etc/subuid_ and the UID of the user calling Podman. + +First mapping step: + +| host UID | intermediate UID | +| - | - | +| UID for the user starting Podman | 0 | +| 1st subordinate UID for the user starting Podman | 1 | +| 2nd subordinate UID for the user starting Podman | 2 | +| 3rd subordinate UID for the user starting Podman | 3 | +| nth subordinate UID for the user starting Podman | n | + +To be able to use intermediate UIDs greater than zero, the user needs to have +subordinate UIDs configured in _/etc/subuid_. See **subuid**(5). + +The second mapping step is configured with **\-\-uidmap**. + +If for example _amount_ is **5** the second mapping step would look like: + +| intermediate UID | container UID | +| - | - | +| _from_uid_ | _container_uid_ | +| _from_uid_ + 1 | _container_uid_ + 1 | +| _from_uid_ + 2 | _container_uid_ + 2 | +| _from_uid_ + 3 | _container_uid_ + 3 | +| _from_uid_ + 4 | _container_uid_ + 4 | + +Even if a user does not have any subordinate UIDs in _/etc/subuid_, +**\-\-uidmap** could still be used to map the normal UID of the user to a +container UID by running `podman create --uidmap $container_uid:0:1 --user $container_uid ...`. #### **\-\-ulimit**=*option* @@ -1032,9 +1103,9 @@ Create a bind mount. If you specify, ` -v /HOST-DIR:/CONTAINER-DIR`, Podman bind mounts `/HOST-DIR` in the host to `/CONTAINER-DIR` in the Podman container. Similarly, `-v SOURCE-VOLUME:/CONTAINER-DIR` will mount the volume in the host to the container. If no such named volume exists, Podman will -create one. The `OPTIONS` are a comma delimited list and can be: <sup>[[1]](#Footnote1)</sup> (Note when using the remote client, the volumes will be mounted from the remote server, not necessarly the client machine.) +create one. The `OPTIONS` are a comma-separated list and can be: <sup>[[1]](#Footnote1)</sup> (Note when using the remote client, the volumes will be mounted from the remote server, not necessarly the client machine.) -The _options_ is a comma delimited list and can be: +The _options_ is a comma-separated list and can be: * **rw**|**ro** * **z**|**Z** @@ -1124,7 +1195,7 @@ host into the container to allow speeding up builds. Content mounted into the container is labeled with the private label. On SELinux systems, labels in the source directory must be readable by the container label. Usually containers can read/execute `container_share_t` -and can read/write `container_file_t`. If you can not change the labels on a +and can read/write `container_file_t`. If you cannot change the labels on a source volume, SELinux container separation must be disabled for the container to work. - The source directory mounted into the container with an overlay mount @@ -1184,10 +1255,14 @@ will convert /foo into a `shared` mount point. Alternatively one can directly change propagation properties of source mount. Say `/` is source mount for `/foo`, then use `mount --make-shared /` to convert `/` into a `shared` mount. +Note: if the user only has access rights via a group, accessing the volume +from inside a rootless container will fail. Use the `--group-add keep-groups` +flag to pass the user's supplementary group access into the container. + #### **\-\-volumes-from**[=*CONTAINER*[:*OPTIONS*]] Mount volumes from the specified container(s). Used to share volumes between -containers. The *options* is a comma delimited list with the following available elements: +containers. The *options* is a comma-separated list with the following available elements: * **rw**|**ro** * **z** @@ -1292,6 +1367,12 @@ $ podman create --name container3 --requires container1,container2 -t -i fedora $ podman start --attach container3 ``` +### Configure keep supplemental groups for access to volume + +``` +$ podman create -v /var/lib/design:/var/lib/design --group-add keep-groups ubi8 +``` + ### Rootless Containers Podman runs as a non root user on most systems. This feature requires that a new enough version of shadow-utils |