community.postgresql.postgresql_pg_hba module – Add, remove or modify a rule in a pg_hba file

Note

This module is part of the community.postgresql collection (version 3.7.0).

You might already have this collection installed if you are using the ansible package. It is not included in ansible-core. To check whether it is installed, run ansible-galaxy collection list.

To install it, use: ansible-galaxy collection install community.postgresql. You need further requirements to be able to use this module, see Requirements for details.

To use it in a playbook, specify: community.postgresql.postgresql_pg_hba.

Synopsis

  • The fundamental function of the module is to create, or delete lines in pg_hba files.

  • The lines in the file should be in a typical pg_hba form and lines should be unique per key (type, databases, users, source). If they are not unique and the SID is ‘the one to change’, only one for state=present or none for state=absent of the SID’s will remain.

Requirements

The below requirements are needed on the host that executes this module.

  • ipaddress

Parameters

Parameter

Comments

address

aliases: source, src

string

The source address/net where the connections could come from.

Will not be used for entries of type=local.

You can also use keywords all, samehost, and samenet.

Default: "samehost"

attributes

aliases: attr

string

The attributes the resulting filesystem object should have.

To get supported flags look at the man page for chattr on the target system.

This string should contain the attributes in the same order as the one displayed by lsattr.

The = operator is assumed as default, otherwise + or - operators need to be included in the string.

backup

boolean

If set, create a backup of the pg_hba file before it is modified. The location of the backup is returned in the (backup) variable by this module.

Choices:

  • false ← (default)

  • true

backup_file

string

Write backup to a specific backupfile rather than a temp file.

comment

string

added in community.postgresql 1.5.0

A comment that will be placed in the same line behind the rule. See also the keep_comments_at_rules parameter.

contype

string

Type of the rule. If not set, postgresql_pg_hba will only return contents.

Choices:

  • "local"

  • "host"

  • "hostnossl"

  • "hostssl"

  • "hostgssenc"

  • "hostnogssenc"

create

boolean

Create an pg_hba file if none exists.

When set to false, an error is raised when the pg_hba file doesn’t exist.

Choices:

  • false ← (default)

  • true

databases

string

Databases this line applies to.

Default: "all"

dest

path / required

Path to pg_hba file to modify.

group

string

Name of the group that should own the filesystem object, as would be fed to chown.

When left unspecified, it uses the current group of the current user unless you are root, in which case it can preserve the previous ownership.

keep_comments_at_rules

boolean

added in community.postgresql 1.5.0

If true, comments that stand together with a rule in one line are kept behind that line.

If false, such comments are moved to the beginning of the file, like all other comments.

Choices:

  • false ← (default)

  • true

method

string

Authentication method to be used.

Choices:

  • "cert"

  • "gss"

  • "ident"

  • "krb5"

  • "ldap"

  • "md5" ← (default)

  • "pam"

  • "password"

  • "peer"

  • "radius"

  • "reject"

  • "scram-sha-256"

  • "sspi"

  • "trust"

mode

any

The permissions the resulting filesystem object should have.

For those used to /usr/bin/chmod remember that modes are actually octal numbers. You must give Ansible enough information to parse them correctly. For consistent results, quote octal numbers (for example, '644' or '1777') so Ansible receives a string and can do its own conversion from string into number. Adding a leading zero (for example, 0755) works sometimes, but can fail in loops and some other circumstances.

Giving Ansible a number without following either of these rules will end up with a decimal number which will have unexpected results.

As of Ansible 1.8, the mode may be specified as a symbolic mode (for example, u+rwx or u=rw,g=r,o=r).

If mode is not specified and the destination filesystem object does not exist, the default umask on the system will be used when setting the mode for the newly created filesystem object.

If mode is not specified and the destination filesystem object does exist, the mode of the existing filesystem object will be used.

Specifying mode is the best way to ensure filesystem objects are created with the correct permissions. See CVE-2020-1736 for further details.

netmask

string

The netmask of the source address.

options

string

Additional options for the authentication method.

overwrite

boolean

Remove all existing rules before adding rules. (Like state=absent for all pre-existing rules.)

Choices:

  • false ← (default)

  • true

owner

string

Name of the user that should own the filesystem object, as would be fed to chown.

When left unspecified, it uses the current user unless you are root, in which case it can preserve the previous ownership.

Specifying a numeric username will be assumed to be a user ID and not a username. Avoid numeric usernames to avoid this confusion.

rules

list / elements=dictionary

A list of objects, specifying rules for the pg_hba.conf. Use this to manage multiple rules at once.

Each object can have the following keys (the ‘rule-specific arguments’), which are treated the same as if they were arguments of this module:

address, comment, contype, databases, method, netmask, options, state, users

See also rules_behavior.

rules_behavior

string

Configure how the rules argument works together with the rule-specific arguments outside the rules argument.

See rules for the complete list of rule-specific arguments.

When set to conflict, fail if rules and, for example, address are set.

If combine, the normal rule-specific arguments are not defining a rule, but are used as defaults for the arguments in the rules argument.

Is used only when rules is specified, ignored otherwise.

Choices:

  • "conflict" ← (default)

  • "combine"

selevel

string

The level part of the SELinux filesystem object context.

This is the MLS/MCS attribute, sometimes known as the range.

When set to _default, it will use the level portion of the policy if available.

serole

string

The role part of the SELinux filesystem object context.

When set to _default, it will use the role portion of the policy if available.

setype

string

The type part of the SELinux filesystem object context.

When set to _default, it will use the type portion of the policy if available.

seuser

string

The user part of the SELinux filesystem object context.

By default it uses the system policy, where applicable.

When set to _default, it will use the user portion of the policy if available.

state

string

The lines will be added/modified when state=present and removed when state=absent.

Choices:

  • "absent"

  • "present" ← (default)

unsafe_writes

boolean

Influence when to use atomic operation to prevent data corruption or inconsistent reads from the target filesystem object.

By default this module uses atomic operations to prevent data corruption or inconsistent reads from the target filesystem objects, but sometimes systems are configured or just broken in ways that prevent this. One example is docker mounted filesystem objects, which cannot be updated atomically from inside the container and can only be written in an unsafe manner.

This option allows Ansible to fall back to unsafe methods of updating filesystem objects when atomic operations fail (however, it doesn’t force Ansible to perform unsafe writes).

IMPORTANT! Unsafe writes are subject to race conditions and can lead to data corruption.

Choices:

  • false ← (default)

  • true

users

string

Users this line applies to.

Default: "all"

Attributes

Attribute

Support

Description

check_mode

Support: full

Can run in check_mode and return changed status prediction without modifying target

diff_mode

Support: full

Will return details on what has changed (or possibly needs changing in check_mode), when in diff mode

Notes

Note

  • The default authentication assumes that on the host, you are either logging in as or sudo’ing to an account with appropriate permissions to read and modify the file.

  • This module also returns the pg_hba info. You can use this module to only retrieve it by only specifying dest. The info can be found in the returned data under key pg_hba, being a list, containing a dict per rule.

  • This module will sort resulting pg_hba files if a rule change is required. This could give unexpected results with manual created hba files, if it was improperly sorted. For example a rule was created for a net first and for a ip in that net range next. In that situation, the ‘ip specific rule’ will never hit, it is in the pg_hba file obsolete. After the pg_hba file is rewritten by the community.postgresql.postgresql_pg_hba module, the ip specific rule will be sorted above the range rule. And then it will hit, which will give unexpected results.

See Also

See also

PostgreSQL pg_hba.conf file reference

Complete reference of the PostgreSQL pg_hba.conf file documentation.

Examples

- name: Grant users joe and simon access to databases sales and logistics from ipv6 localhost ::1/128 using peer authentication
  community.postgresql.postgresql_pg_hba:
    dest: /var/lib/postgres/data/pg_hba.conf
    contype: host
    users: joe,simon
    source: ::1
    databases: sales,logistics
    method: peer
    create: true

- name: Grant user replication from network 192.168.0.100/24 access for replication with client cert authentication
  community.postgresql.postgresql_pg_hba:
    dest: /var/lib/postgres/data/pg_hba.conf
    contype: host
    users: replication
    source: 192.168.0.100/24
    databases: replication
    method: cert

- name: Revoke access from local user mary on database mydb
  community.postgresql.postgresql_pg_hba:
    dest: /var/lib/postgres/data/pg_hba.conf
    contype: local
    users: mary
    databases: mydb
    state: absent

- name: Grant some_user access to some_db, comment that and keep other rule-specific comments attached to their rules
  community.postgresql.postgresql_pg_hba:
    dest: /var/lib/postgres/data/pg_hba.conf
    contype: host
    users: some_user
    databases: some_db
    method: md5
    source: ::/0
    keep_comments_at_rules: true
    comment: "this rule is an example"

- name: Replace everything with a new set of rules
  community.postgresql.postgresql_pg_hba:
    dest: /var/lib/postgres/data/pg_hba.conf
    overwrite: true # remove preexisting rules

    # custom defaults
    rules_behavior: combine
    contype: hostssl
    address: 2001:db8::/64
    comment: added in bulk

    rules:
    - users: user1
      databases: db1
      # contype, address and comment come from custom default
    - users: user2
      databases: db2
      comment: added with love # overwrite custom default for this rule
      # contype and address come from custom default
    - users: user3
      databases: db3
      # contype, address and comment come from custom default

Return Values

Common return values are documented here, the following are the fields unique to this module:

Key

Description

backup_file

string

File that the original pg_hba file was backed up to.

Returned: changed

Sample: "/tmp/pg_hba_jxobj_p"

msgs

list / elements=string

List of textual messages what was done.

Returned: success

Sample: {"msgs": ["Removing", "Changed", "Writing"]}

pg_hba

list / elements=string

List of the pg_hba rules as they are configured in the specified hba file.

Returned: success

Sample: {"pg_hba": [{"db": "all", "method": "md5", "src": "samehost", "type": "host", "usr": "all"}]}

Authors

  • Sebastiaan Mannem (@sebasmannem)

  • Felix Hamme (@betanummeric)