feat(samba_server): new role for SMB/CIFS shares

Mirrors the nfs_server design: standalone tdbsam server, per-share access
control (valid_users, write_list, force_user/group), optional guest fallback
(map to guest = Bad User), UFW rules for ports 445/139, testparm-validated
config, idempotent smbpasswd user creation.
This commit is contained in:
Clément Désiles
2026-05-30 21:57:13 +02:00
parent b2a66099aa
commit a6ca97ca0e
5 changed files with 277 additions and 0 deletions
+72
View File
@@ -0,0 +1,72 @@
# Samba Server
Minimal SMB/CIFS file sharing, mirroring the design of the `nfs_server` role.
Security is assumed to come from the network (firewall + VPN). No Active
Directory, no Kerberos, no winbind. Standalone server, `tdbsam` backend.
## In a nutshell
**Supports:**
- SMB2/SMB3 over TCP (port 445) and legacy NetBIOS (port 139)
- Per-share access control (`valid_users`, `write_list`, `force_user/group`)
- Optional guest fallback (`map to guest = Bad User`)
- UFW firewall configuration
- `testparm`-validated config before reload
- Idempotent user creation via `smbpasswd`
**Limitations:**
- No Active Directory / Kerberos integration
- Samba user accounts are only **created**, never updated. To rotate a
password, run `pdbedit -x <username>` first, then rerun the playbook.
- The matching system user (`/etc/passwd`) must already exist; this role
does not create UNIX accounts.
## Inventory
```yaml
# Bind only to private interfaces
samba_bind_interfaces_only: true
samba_interfaces:
- lo
- lan0
- 192.168.1.161
# UNIX users must exist beforehand (e.g. via the `users` role
# or manual `useradd`). This role only manages the SMB password.
samba_users:
- username: alice
password: "{{ vault_alice_smb_password }}"
- username: bob
password: "{{ vault_bob_smb_password }}"
samba_shares:
- name: photos
path: /mnt/andromeda/family-photos
comment: "Family photos"
read_only: false
valid_users: ["alice", "bob"]
write_list: ["alice"]
force_user: alice
force_group: users
- name: public
path: /mnt/andromeda/public
comment: "Read-only public share"
guest_ok: true
read_only: true
samba_server_firewall_allowed_sources:
- 192.168.1.0/24
- 192.168.27.0/27
```
See [`defaults/main.yml`](./defaults/main.yml) for all variables and defaults.
## Resources
- https://wiki.archlinux.org/title/Samba
- https://wiki.samba.org/index.php/Setting_up_Samba_as_a_Standalone_Server
- `man smb.conf`, `man smbpasswd`, `man pdbedit`
+64
View File
@@ -0,0 +1,64 @@
---
# Global server identity
samba_workgroup: "WORKGROUP"
samba_server_string: "Samba Server"
samba_netbios_name: "{{ inventory_hostname | upper }}"
# Map unknown users to guest (similar to NFS all_squash).
# "Never" disables guest fallback, "Bad User" maps unknown users to guest.
samba_map_to_guest: "Bad User"
samba_guest_account: "nobody"
# Interfaces to bind samba listeners to.
# `bind interfaces only` is always enabled. If samba_interfaces is empty,
# samba binds to no interface and is effectively isolated.
samba_interfaces: []
# Example:
# samba_interfaces:
# - lo
# - lan0
# - 192.168.1.161
# Samba user accounts. The matching system user MUST already exist
# (created by another role or manually). The role only manages the
# samba password (smbpasswd) and is idempotent: existing users are
# not touched. To rotate a password, delete it first with
# `pdbedit -x <username>` then rerun the playbook.
samba_users: []
# Example:
# samba_users:
# - username: alice
# password: "secret"
# Shares
samba_shares: []
# Example:
# samba_shares:
# - name: photos
# path: /mnt/andromeda/family-photos
# comment: "Family photos"
# browseable: true # default: true
# read_only: false # default: true
# guest_ok: false # default: false
# valid_users: ["alice"] # optional
# write_list: ["alice"] # optional
# force_user: alice # optional
# force_group: users # optional
# create_mask: "0664" # default: 0664
# directory_mask: "0775" # default: 0775
# manage_directory: false # default: false (do not create/chown the dir)
# extra_options: # optional, raw smb.conf key/values
# "veto files": "/.DS_Store/"
samba_config_file: "/etc/samba/smb.conf"
# smbd defaults to 445 (SMB) and 139 (NetBIOS Session)
samba_port_smb: 445
samba_port_netbios: 139
samba_server_firewall_allowed_sources:
- 127.0.0.0/8
# OS-dependent service name
samba_service_name: >-
{{ (ansible_facts['os_family'] == 'Archlinux') | ternary('smb', 'smbd') }}
+6
View File
@@ -0,0 +1,6 @@
---
- name: Restart samba
ansible.builtin.systemd:
name: "{{ samba_service_name }}"
state: restarted
daemon_reload: true
+87
View File
@@ -0,0 +1,87 @@
---
- name: Validate samba users have a password set
ansible.builtin.assert:
that:
- item.username is defined and item.username | length > 0
- item.password is defined and item.password | length >= 8
fail_msg: |
Each samba_users entry must define `username` and `password` (>=8 chars).
See roles/samba_server/defaults/main.yml for the expected schema.
loop: "{{ samba_users }}"
loop_control:
label: "{{ item.username | default('<unnamed>') }}"
no_log: true
- name: Install samba
ansible.builtin.package:
name: samba
state: present
- name: Configure samba
ansible.builtin.template:
src: smb.conf.j2
dest: "{{ samba_config_file }}"
owner: root
group: root
mode: "0644"
validate: "testparm -s %s"
notify: Restart samba
- name: Ensure share directories exist
ansible.builtin.file:
path: "{{ item.path }}"
state: directory
owner: "{{ item.force_user | default('root') }}"
group: "{{ item.force_group | default('root') }}"
mode: "{{ item.directory_mask | default('0775') }}"
loop: "{{ samba_shares }}"
loop_control:
label: "{{ item.name }}"
when: item.manage_directory | default(false)
- name: Verify system users exist for samba accounts
ansible.builtin.getent:
database: passwd
key: "{{ item.username }}"
loop: "{{ samba_users }}"
loop_control:
label: "{{ item.username }}"
- name: Check existing samba users
ansible.builtin.command: pdbedit -L
register: samba_existing_users
changed_when: false
failed_when: false
- name: Add samba users
ansible.builtin.shell: |
set -o pipefail
(echo "{{ item.password }}"; echo "{{ item.password }}") | smbpasswd -s -a "{{ item.username }}"
args:
executable: /bin/bash
loop: "{{ samba_users }}"
loop_control:
label: "{{ item.username }}"
when: item.username not in (samba_existing_users.stdout | default(''))
changed_when: true
no_log: true
- name: Systemd service for samba is started and enabled
ansible.builtin.systemd:
name: "{{ samba_service_name }}"
state: started
enabled: true
- name: Setup firewall rules for samba
community.general.ufw:
rule: allow
src: "{{ item.0 }}"
port: "{{ item.1 }}"
proto: tcp
direction: in
comment: "Samba (SMB)"
loop: "{{ samba_server_firewall_allowed_sources | product([samba_port_smb, samba_port_netbios]) | list }}"
retries: 5
delay: 2
register: ufw_result
until: ufw_result is succeeded
+48
View File
@@ -0,0 +1,48 @@
# {{ ansible_managed }}
[global]
workgroup = {{ samba_workgroup }}
server string = {{ samba_server_string }}
netbios name = {{ samba_netbios_name }}
server role = standalone server
security = user
passdb backend = tdbsam
map to guest = {{ samba_map_to_guest }}
guest account = {{ samba_guest_account }}
bind interfaces only = yes
interfaces = {{ samba_interfaces | join(' ') }}
log file = /var/log/samba/log.%m
max log size = 1000
logging = file
disable netbios = no
dns proxy = no
{% for share in samba_shares %}
[{{ share.name }}]
path = {{ share.path }}
{% if share.comment is defined %}
comment = {{ share.comment }}
{% endif %}
browseable = {{ share.browseable | default(true) | ternary('yes', 'no') }}
read only = {{ share.read_only | default(true) | ternary('yes', 'no') }}
guest ok = {{ share.guest_ok | default(false) | ternary('yes', 'no') }}
{% if share.valid_users is defined %}
valid users = {{ share.valid_users | join(' ') }}
{% endif %}
{% if share.write_list is defined %}
write list = {{ share.write_list | join(' ') }}
{% endif %}
{% if share.force_user is defined %}
force user = {{ share.force_user }}
{% endif %}
{% if share.force_group is defined %}
force group = {{ share.force_group }}
{% endif %}
create mask = {{ share.create_mask | default('0664') }}
directory mask = {{ share.directory_mask | default('0775') }}
{% if share.extra_options is defined %}
{% for k, v in share.extra_options.items() %}
{{ k }} = {{ v }}
{% endfor %}
{% endif %}
{% endfor %}