Design notes for work on https://issues.jboss.org/browse/WFLY-456 (formerly https://issues.jboss.org/browse/AS7-444).
My current development topic branch for this is https://github.com/kabir/wildfly/tree/WFLY-456-audit-log (More current than https://github.com/bstansberry/jboss-as/tree/AS7-444, note that these are personal branches; I make no guarantees not to change its commit history.) This branch is based on work previously done by John Bailey.
Design notes:
1) Processing location in OperationContext
a) when done
b) when decision to not proceed is made in OperationContext
2) Log record format:
a) date
b) read-only?
c) boot?
d) (if boot) version (as string???)
e) rollback?
f) userid (TODO get this somehow)
g) uuid (for domain ops only, to track across processes)
h) isServer?
i) primary (domain or server) model hash
j) if (!isServer) secondary (host) model hash
k) overall hash
l) num operations
m) operations (one at a time)
n) length of a->j (scan from end to last boot during validation; alternative is to write the length first and scan from beginning to last boot)
3) Index record format:
a) overall hash
4) Mgmt operations
a) truncate (back to last boot)
i) don't discard previous; just write under a different file name
b) read log (params -- from (default 0); batch-size (default 20; -1 means all))
c) validate log
d) config changes
5) Validation:
a) compare persisted model hash to current model
b) scan back through log to last config-file-modified boot or version-change boot. We stop at version-change boot to avoid spurious validation problems resulting from changes in model construction across versions
c) recreate by re-running ops
-- validation problems
a) need to verify model hash at each stage -- special controller that ignores all runtime ops
i) problem -- how to recreate domain ops involving remote slaves that don't exist?
ii) problem -- ops with attachments -- attachments won't exist
iii) this "special controller" could end up duplicating a lot of logic just for validation
b) reads and runtime ops cannot be verified against model; it can only be confirmed that their hash is consistent with subsequent hashes in the log. Tamper resistant as modification would require modifying all subsequent log entries, but not tamper proof as this could be done.
6) Domain mode
a) tracking requests from master to slaves
apply a uuid to requests
-- as a header
include uuid in log record
b) detecting host.xml config changes at boot
problem -- can't detect host.xml config changes at boot, as model changes may be due to domain.xml stuff coming from the master
so, independent domain and host logging
but, what about non-model affecting ops? log twice?
c) domain logging on slaves? only if --backup-dc is set? -- no simpler to just log
d) remote-slave-only logging on master?
yes, to maintain a complete record of what was done
7) Non-model-affecting ops
a) re-calculating the model hash for all such ops is too expensive
b) store the hash(es) in the ModelController along with the model
c) provide the hash along with the model to OperationContext
d) when model is updated recalc hashes
8) Config
a) <audit-log> element
b) part of <management> section
c) resource is /core-service=audit-log
d) attributes
i) path (NO -- we need to know the location when first logging, before we have processed ops to set it)
ii) relative-to (NO -- we need to know the location when first logging, before we have processed ops to set it)
iii) log-read-only?
iv) daily-rolling??? (hassle; tempting to defer to later release but it's probably necessary immediately)
9) Other issues
a) disable logging overhead for dev scenarios
i) to disable it during initial boot (until whatever config element that turns it on/off is read) -- maintain log data in memory and only write on last boot op
b) parallel boot handlers should not log
c) fluctuating model hashes
i) if op took the controller lock, that lock ensures proper ordering of model hashes
ii) if op does not take controller lock (reads) earlier model hashes can intermix with later -- validation needs to account for this
Suggested configuration
Only relevant elements to audit logging have been included in the following examples.
jboss-as-config (i.e. standlone.xml and host.xml)
This defines a set of audit-log-appenders which are referenced by the audit-log element.
Currently encryption/tamper detection is not a requirement so all logs are done in clear text. If encryption/tamper detection later becomes a requirement this could be added by for example an audit-log-formatters section which configures whatever we would like to use for encryption/tamper detection and the file-audit-log-appender and syslog-audit-log-appender could individually be made to reference an audit-log-formatter.
<xs:complexType name="domain-managementType">
<xs:annotation>
<xs:documentation>
Domain-wide default configuration settings for the management of standalone servers and a Host Controller.
</xs:documentation>
</xs:annotation>
<xs:sequence>
<xs:element name="security-realms" minOccurs="0">
<xs:complexType>
<xs:sequence>
<xs:element name="security-realm" type="security-realmType" minOccurs="1"
maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="outbound-connections" minOccurs="0">
<xs:complexType>
<xs:sequence>
<xs:element name="ldap" type="ldapType" minOccurs="1" />
</xs:sequence>
<xs:attribute name="protocol" use="required">
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="udp"/>
<xs:enumeration value="tcp"/>
<xs:enumeration value="tls"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="host" default="localhost"/>
<xs:attribute name="port" default="514"/>
</xs:complexType>
<xs:complexType name="audit-logType">
<xs:annotation>
<xs:documentation>
Declaration of management operation audit logging configuration coming from the model controller core.
</xs:documentation>
</xs:annotation>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element name="appenders" type="audit-log-appenders-refType" minOccurs="0"/>
</xs:choice>
<xs:attribute name="log-read-only" type="xs:boolean" default="false">
<xs:annotation>
<xs:documentation>
Whether operations that do not modify the configuration or any runtime services should be logged.
</xs:documentation>
</xs:annotation>
</xs:attribute>
<xs:attribute name="enabled" type="xs:boolean" default="true">
<xs:annotation>
<xs:documentation>
Whether audit logging is enabled.
</xs:documentation>
</xs:annotation>
</xs:attribute>
</xs:complexType>
<xs:complexType name="audit-log-appenders-refType">
<xs:annotation>
<xs:documentation>
References to audit-log-appenders defined in the audit-log-appenders section
</xs:documentation>
</xs:annotation>
<xs:choice minOccurs="1">
<xs:element name="appender" type="audit-log-appender-refType" minOccurs="0"/>
</xs:choice>
</xs:complexType>
<xs:complexType name="audit-log-appender-refType">
<xs:annotation>
<xs:documentation>
A reference to an audit-log-appender defined in the audit-log-appenders section
</xs:documentation>
</xs:annotation>
<xs:attribute name="appender" type="xs:string" use="required"/>
</xs:complexType>
jboss-as-jmx (jmx subsystem)
References the appenders set up in the audit-log-appenders section. This allows for both shared and separate audit logs for core management operations and jmx operations.
<xs:complexType name="subsystem">
<xs:sequence>
<xs:element name="expose-resolved-model" type="resolvedModelType" minOccurs="0" maxOccurs="1"/>
<xs:element name="expose-expression-model" type="expressionModelType" minOccurs="0" maxOccurs="1"/>
<xs:element name="remoting-connector" type="remotingConnectorRefType" minOccurs="0"/>
<xs:element name="audit-log" type="audit-logType" minOccurs="0"/>
</xs:sequence>
</xs:complexType>
<xs:complexType name="audit-logType">
<xs:annotation>
<xs:documentation>
Declaration of management operation audit logging configuration.
</xs:documentation>
</xs:annotation>