Chapter 7. Security

Securing your router network involves configuring authentication and authorization. You can authenticate and encrypt the router’s connections using SSL/TLS or SASL. Additionally, you can authorize access to messaging resources by setting user connection restrictions and defining AMQP resource access control.

7.1. Authenticating Remote Peers

You can configure AMQ Interconnect to communicate with clients, routers, and brokers in a secure way by authenticating and encrypting the router’s connections. AMQ Interconnect supports the following security protocols:

SSL/TLS for certificate-based encryption and mutual authentication
SASL for authentication and payload encryption

7.2. Setting Up SSL/TLS for Encryption and Authentication

Before you can secure incoming and outgoing connections using SSL/TLS encryption and authentication, you must first set up the SSL/TLS profile in the router’s configuration file.

Prerequisites

You must have the following files in PEM format:

An X.509 CA certificate (used for signing the router certificate for the SSL/TLS server authentication feature).
A private key (with or without password protection) for the router.
An X.509 router certificate signed by the X.509 CA certificate.

Procedure

In the router’s configuration file, add an sslProfile section:
```
sslProfile {
    name: NAME
    ciphers: CIPHERS
    certDb: PATH.pem
    certFile: PATH.pem
    keyFile: PATH.pem
    password: PASSWORD/PATH_TO_PASSWORD_FILE
    ...
}
```
name
A name for the SSL/TLS profile. You can use this name to refer to the profile from the incoming and outgoing connections.
For example:
```
name: router-ssl-profile
```
ciphers
The SSL cipher suites that can be used by this SSL/TLS profile. If certain ciphers are unsuitable for your environment, you can use this attribute to restrict them from being used.
To enable a cipher list, enter one or more cipher strings separated by colons (:). For example:
```
ciphers: ALL:!aNULL:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP
```
To see the full list of available ciphers, use the openssl ciphers command. For more information about each cipher, see the ciphers man page.
certDb
The absolute path to the database that contains the public certificates of trusted certificate authorities (CA).
For example:
```
certDb: /qdrouterd/ssl_certs/ca-cert.pem
```
certFile
The absolute path to the file containing the PEM-formatted public certificate to be used on the local end of any connections using this profile.
For example:
```
certFile: /qdrouterd/ssl_certs/router-cert-pwd.pem
```
keyFile
The absolute path to the file containing the PEM-formatted private key for the above certificate.
For example:
```
keyFile: /qdrouterd/ssl_certs/router-key-pwd.pem
```
passwordFile or password
If the private key is password-protected, you must provide the password by either specifying the absolute path to a file containing the password that unlocks the certificate key, or entering the password directly in the configuration file.
For example:
```
password: routerKeyPassword
```
For information about additional sslProfile attributes, see sslProfile in the qdrouterd.conf man page.

7.3. Setting Up SASL for Authentication and Payload Encryption

If you plan to use SASL to authenticate connections, you must first add the SASL attributes to the router entity in the router’s configuration file. These attributes define a set of SASL parameters that can be used by the router’s incoming and outgoing connections.

Prerequisites

Before you can set up SASL, you must have the following:

The SASL database is generated.
The SASL configuration file is configured.
The Cyrus SASL plugin is installed for each SASL mechanism you plan to use.
Cyrus SASL uses plugins to support specific SASL mechanisms. Before you can use a particular SASL mechanism, the relevant plugin must be installed. For example, you need the cyrus-sasl-plain plugin to use SASL PLAIN authentication.
To see a list of Cyrus SASL plugins in Red Hat Enterprise Linux, use the yum search cyrus-sasl command. To install a Cyrus SASL plugin, use the yum install PLUGIN command.

Procedure

In the router’s configuration file, add the following attributes to the router section:
```
router {
    ...
    saslConfigPath: PATH
    saslConfigName: FILE_NAME
}
```
saslConfigPath
The absolute path to the SASL configuration file.
For example:
```
saslConfigPath: /qdrouterd/security
```
saslConfigName
The name of the SASL configuration file. This name should not include the .conf file extension.
For example:
```
saslConfigName: qdrouterd_sasl
```

7.4. Securing Incoming Connections

You can secure incoming connections by configuring each connection’s listener entity for encryption, authentication, or both.

Prerequisites

Before securing incoming connections, the security protocols you plan to use should be set up.

Choices

7.4.1. Adding SSL/TLS Encryption to an Incoming Connection

You can configure an incoming connection to accept encrypted connections only. By adding SSL/TLS encryption, to connect to this router, a remote peer must first start an SSL/TLS handshake with the router and be able to validate the server certificate received by the router during the handshake.

Procedure

In the router’s configuration file, add the following attributes to the connection’s listener entity:
```
listener {
    ...
    sslProfile: SSL_PROFILE_NAME
    requireSsl: yes
}
```
sslProfile
The name of the SSL/TLS profile you set up.
requireSsl
Enter yes to require all clients connecting to the router on this connection to use encryption.

7.4.2. Adding SASL Authentication to an Incoming Connection

You can configure an incoming connection to authenticate the client using SASL. You can use SASL authentication with or without SSL/TLS encryption.

Procedure

In the router’s configuration file, add the following attributes to the connection’s listener section:
```
listener {
    ...
    authenticatePeer: yes
    saslMechanisms: MECHANISMS
}
```
authenticatePeer
Set this attribute to yes to require the router to authenticate the identity of a remote peer before it can use this incoming connection.
saslMechanisms
The SASL authentication mechanism (or mechanisms) to use for peer authentication. You can choose any of the Cyrus SASL authentication mechanisms except for ANONYMOUS. To specify multiple authentication mechanisms, separate each mechanism with a space.
For a full list of supported Cyrus SASL authentication mechanisms, see Authentication Mechanisms.

7.4.3. Adding SSL/TLS Client Authentication to an Incoming Connection

You can configure an incoming connection to authenticate the client using SSL/TLS.

The base SSL/TLS configuration provides content encryption and server authentication, which means that remote peers can verify the router’s identity, but the router cannot verify a peer’s identity.

However, you can require an incoming connection to use SSL/TLS client authentication, which means that remote peers must provide an additional certificate to the router during the SSL/TLS handshake. By using this certificate, the router can verify the client’s identity without using a username and password.

You can use SSL/TLS client authentication with or without SASL authentication.

Procedure

In the router’s configuration, file, add the following attribute to the connection’s listener entity:
```
listener {
    ...
    authenticatePeer: yes
}
```
authenticatePeer
Set this attribute to yes to require the router to authenticate the identity of a remote peer before it can use this incoming connection.

7.4.4. Adding SASL Payload Encryption to an Incoming Connection

If you do not use SSL/TLS, you can still encrypt the incoming connection by using SASL payload encryption.

Procedure

In the router’s configuration file, add the following attributes to the connection’s listener section:
```
listener {
    ...
    requireEncryption: yes
    saslMechanisms: MECHANISMS
}
```
requireEncryption
Set this attribute to yes to require the router to use SASL payload encryption for the connection.
saslMechanisms
The SASL mechanism to use. You can choose any of the Cyrus SASL authentication mechanisms. To specify multiple authentication mechanisms, separate each mechanism with a space.
For a full list of supported Cyrus SASL authentication mechanisms, see Authentication Mechanisms.

7.5. Securing Outgoing Connections

You can secure outgoing connections by configuring each connection’s connector entity for encryption, authentication, or both.

Prerequisites

Before securing outgoing connections, the security protocols you plan to use should be set up.

Choices

7.5.1. Adding SSL/TLS Client Authentication to an Outgoing Connection

If an outgoing connection connects to an external client configured with mutual authentication, you should ensure that the outgoing connection is configured to provide the external client with a valid security certificate during the SSL/TLS handshake.

You can use SSL/TLS client authentication with or without SASL authentication.

Procedure

In the router’s configuration file, add the sslProfile attribute to the connection’s connector entity:
```
connector {
    ...
    sslProfile: SSL_PROFILE_NAME
}
```
sslProfile
The name of the SSL/TLS profile you set up.

7.5.2. Adding SASL Authentication to an Outgoing Connection

You can configure an outgoing connection to provide authentication credentials to the external container. You can use SASL authentication with or without SSL/TLS encryption.

Procedure

In the router’s configuration file, add the saslMechanisms attribute to the connection’s connector entity:
```
connector {
    ...
    saslMechanisms: MECHANISMS
    saslUsername: USERNAME
    saslPassword: PASSWORD
}
```
saslMechanisms
One or more SASL mechanisms to use to authenticate the router to the external container. You can choose any of the Cyrus SASL authentication mechanisms. To specify multiple authentication mechanisms, separate each mechanism with a space.
For a full list of supported Cyrus SASL authentication mechanisms, see Authentication Mechanisms.
saslUsername
If any of the SASL mechanisms uses username/password authentication, then provide the username to connect to the external container.
saslPassword
If any of the SASL mechanisms uses username/password authentication, then provide the password to connect to the external container.

7.6. Integrating with Kerberos

By using the GSSAPI SASL mechanism, you can configure AMQ Interconnect to authenticate incoming connections using Kerberos.

Prerequisites

A Kerberos infrastructure must be deployed in your environment.
In the Kerberos environment, a service principal of amqp/HOSTNAME@REALM must be configured.
This is the service principal that AMQ Interconnect uses.
The cyrus-sasl-gssapi package must be installed on each client and router host machine.
SASL must be set up for AMQ Interconnect.

Procedure

On the router’s host machine, open the /etc/sasl2/qdrouterd.conf configuration file.

Example 7.1. An /etc/sasl2/qdrouterd.conf Configuration File

pwcheck_method: auxprop
auxprop_plugin: sasldb
sasldb_path: qdrouterd.sasldb
keytab: /etc/krb5.keytab
mech_list: ANONYMOUS DIGEST-MD5 EXTERNAL PLAIN GSSAPI

Verify the following:
- The mech_list attribute contains the GSSAPI mechanism.
- The keytab attribute points to the location of the keytab file.
Open the router’s configuration file.
For each incoming connection that should use Kerberos for authentication, set the router’s listener to use the GSSAPI mechanism.
Example 7.2. A listener in the Router Configuration File
```
listener {
    ...
    authenticatePeer: yes
    saslMechanisms: GSSAPI
}
```
For more information about these attributes, see Section 7.4.2, “Adding SASL Authentication to an Incoming Connection”.

7.7. Authorizing Access to Messaging Resources

You can restrict the number of user connections, and control access to AMQP messaging resources by configuring policies.

7.7.1. Types of Policies

You can configure two different types of policies: global policies and vhost policies.

Global policies: Settings for the router. A global policy defines the maximum number of incoming user connections for the router (across all vhost policies), and defines how the router should use vhost policies.
Vhost policies: Connection and AMQP resource limits for a messaging endpoint (called an AMQP virtual host, or vhost). A vhost policy defines what a client can access on a messaging endpoint over a particular connection.
Note
A vhost is typically the name of the host to which the client connection is directed. For example, if a client application opens a connection to the amqp://mybroker.example.com:5672/queue01 URL, the vhost would be mybroker.example.com.

The resource limits defined in global and vhost policies are applied to user connections only. The limits do not affect inter-router connections or router connections that are outbound to waypoints.

7.7.2. How AMQ Interconnect Applies Policies

AMQ Interconnect uses both global and vhost policies to determine whether to permit a connection, and if it is permitted, to apply the appropriate resource limits.

When a client creates a connection to the router, the router first determines whether to allow or deny the connection. This decision is based on the following criteria:

Whether the connection will exceed the router’s global connection limit (defined in the global policy)
Whether the connection will exceed the vhost’s connection limits (defined in the vhost policy that matches the host to which the connection is directed)

If the connection is allowed, the router assigns the user (the authenticated user name from the connection) to a user group, and enforces the user group’s resource limits for the lifetime of the connection.

7.7.3. Configuring Global Policies

You can set the incoming connection limit for the router and define how it should use vhost policies by configuring a global policy.

Procedure

In the router configuration file, add a policy section.
```
policy {
    maxConnections: 10000  1
    enableVhostPolicy: true  2
    policyDir: /etc/qpid-dispatch/policies/  3
    defaultVhost: $default  4
}
```
1
The maximum number of concurrent client connections allowed for this router. This limit is always enforced, even if no other policy settings have been defined. The limit is applied to all incoming connections regardless of remote host, authenticated user, or targeted vhost. The default (and the maximum) value is 65535.
2
Enables the router to enforce the connection denials and resource limits defined in the configured vhost policies. The default is false, which means that the router will not enforce any vhost policies.
Note
Setting enableVhostPolicy to false improves the router’s performance.
3
The absolute path to a directory that holds vhost policy definition files in JSON format (*.json). The router processes all of the vhost policies in each JSON file that is in this directory. For more information, see Section 7.7.4, “Configuring Vhost Policies”.
4
The name of the default vhost policy, which is applied to any connection for which a vhost policy has not been configured. The default is $default. If defaultVhost is not defined, then default vhost processing is disabled.

7.7.4. Configuring Vhost Policies

Vhost policies are JSON files that define the connection limits and AMQP resource limits for a messaging endpoint. To configure a vhost policy, you create the vhost policy JSON file and then configure the router to point to the location where you created the file.

A vhost policy consists of the following:

Connection limits
These limits control the number of users that can be connected to the vhost simultaneously.
User groups
A user group defines the messaging resources that the group members are permitted to access. Each user group defines the following:
- A set of users that can connect to the vhost (the group members)
- The remote hosts from which the group members may connect to the router network
- The AMQP resources that the group members are permitted to access on the vhost

Procedure

Determine where to store the vhost policy JSON files.
The directory should be accessible by each router that needs to apply these vhost policies.
In the directory you determined, create a JSON file for each vhost policy.
```
[
    ["vhost", {
        "hostname": "example.com",  1
        "maxConnections": 10000,  2
        "maxConnectionsPerUser": 100,  3
        "maxConnectionsPerHost": 100,  4
        "allowUnknownUser": true,  5
        "groups": {
            "admin": {
                "users": ["admin1", "admin2"],  6
                "remoteHosts": ["127.0.0.1", "::1"],  7
                "sources": "*",  8
                "targets": "*"  9
            },
            "developers": {
                "users": ["dev1", "dev2", "dev3"],
                "remoteHosts": "*",
                "sources": ["myqueue1", "myqueue2"],
                "targets": ["myqueue1", "myqueue2"]
            },
            "$default": {
                "remoteHosts": "*",
                "allowDynamicSource": true,
                "sources": ["myqueue1", "myqueue2"],
                "targets": ["myqueue1", "myqueue2"]
            }
        }
    }]
]
```
1
The hostname of the vhost. This vhost policy will be applied to any client connection that is directed to the hostname that you specify. This name must be unique; you can only have one vhost policy per hostname.
2
The global maximum number of concurrent client connections allowed for this vhost. The default is 65535.
3
The maximum number of concurrent client connections allowed for any user. The default is 65535.
4
The maximum number of concurrent client connections allowed for any remote host (the host from which the client is connecting). The default is 65535.
5
Whether unknown users (users who are not members of a defined user group) are allowed to connect to the vhost. Unknown users are assigned to the $default user group and receive $default settings. The default is false, which means that unknown users are not allowed.
6
A list of authenticated users for this user group. Use commas to separate multiple users. A user may belong to only one vhost user group.
7
A list of remote hosts from which the users may connect. A host can be a hostname, IP address, or IP address range. Use commas to separate multiple hosts. To allow access from all remote hosts, specify a wildcard *. To deny access from all remote hosts, leave this attribute blank.
8
A list of AMQP source addresses from which users in this group may receive messages. If you do not specify any addresses, users in this group are not allowed to receive messages from any addresses.
You can use the substitution token ${user} to specify an AMQP address that contains a user’s authenticated user name. This enables you to allow access to resources specific to each user in the user group without having to name each user individually. You can only specify the ${user} token once in an AMQP address name. If there are multiple tokens in an address, only the leftmost token will be substituted.
You can use an asterisk (*) wildcard to match one or more characters in an AMQP address. However, this wildcard is only recognized if it is the last character in the address name.
Example 7.3. Allowing Access to All Addresses
"sources": "*"
Example 7.4. Restricting Access to All Addresses
"sources": ""
Example 7.5. Allowing Access to Specific Addresses
"sources": ["myaddress01", "myaddress02", "myaddress03"]
Example 7.6. Allowing Access to User-Specific Addresses
This definition allows access to any address that meets any of the following rules:
Starts with the prefix tmp_ and ends with the user name
Starts with the prefix temp followed by any additional characters
Starts with the user name, is followed by -home-, and ends with any additional characters
"sources": ["tmp_${user}", "temp*", "${user}-home-*"]
9
A list of AMQP target addresses from which users in this group may send messages. You can specify multiple AMQP addresses and use user name substitution and wildcards the same way as with source addresses.
In the router configuration file, locate the policy entity and set the policyDir attribute to point to the directory where the vhost policy JSON files are stored.
```
policy {
    maxConnections: 1000
    enableVhostPolicy: true
    policyDir: /etc/vhost-policies/ 1
    defaultVhost: $default
}
```
1
The absolute path to a directory that holds vhost policy definition files in JSON format (*.json). The router processes all of the vhost policies in each JSON file that is in this directory.
Repeat the previous step for each additional router that should use the vhost policies located in the vhost policy directory.

7.7.5. Example: Configuring a Vhost Policy

In this example, a vhost policy defines resource limits for clients connecting to the example.com host.

Example 7.7. A Vhost Policy JSON File

[
    ["vhost", {
        "hostname": "example.com",  1
        "maxConnectionsPerUser": 10,  2
        "allowUnknownUser": true,  3
        "groups": {
            "admin": {
                "users": ["admin1", "admin2"],  4
                "remoteHosts": ["127.0.0.1", "::1"],  5
                "sources": "*",  6
                "targets": "*"  7
            },
            "$default": {
                "remoteHosts": "*",  8
                "sources": ["news*", "sports*", "chat*"],  9
                "targets": "chat*"  10
            }
        }
    }]
]

1: The rules defined in this vhost policy will be applied to any user connecting to example.com.
2: Each user can open up to 10 connections to the vhost.
3: Any user can connect to this vhost. Users that are not part of the admin group are assigned to the $default group.
4: If the admin1 or admin2 user connects to the vhost, they are assigned to the admin user group.
5: Users in the admin user group must connect from localhost. If the admin user attempts to connect from any other host, the connection will be denied.
6: Users in the admin user group can receive from any address offered by the vhost.
7: Users in the admin user group can send to any address offered by the vhost.
8: Any non-admin user is permitted to connect from any host.
9: Non-admin users are permitted to receive messages from any addresses that start with the news, sports, or chat prefixes.
10: Non-admin users are permitted to send messages to any address that start with the chat prefix.

7.7.6. Example: Using a Vhost Policy to Limit Memory Consumption (Advanced)

By using the advanced vhost policy attributes, you can control how much system buffer memory a user connection can potentially consume.

In this example, a stock trading site provides services for stock traders. However, the site must also accept high-capacity, automated data feeds from stock exchanges. To prevent trading activity from consuming memory needed for the feeds, a larger amount of system buffer memory is allotted to the feeds than to the traders.

This examples uses the maxSessions and maxSessionWindow attributes to set the buffer memory consumption limits for each AMQP session. These settings are passed directly to the AMQP connection and session negotiations, and do not require any processing cycles on the router.

This example does not show the vhost policy settings that are unrelated to buffer allocation.

Example 7.8. A Vhost Policy to Limit Memory Consumption

[
    ["vhost", {
        "hostname": "traders.com",  1
        "groups": {
            "traders": {
                "users": ["trader1", "trader2"],  2
                "maxFrameSize": 10000,
                "maxSessionWindow": 5000000,  3
                "maxSessions": 1  4
            },
            "feeds": {
                "users": ["nyse-feed", "nasdaq-feed"],  5
                "maxFrameSize": 60000,
                "maxSessionWindow": 1200000000,  6
                "maxSessions": 3  7
            }
        }
    }]
]

1: The rules defined in this vhost policy will be applied to any user connecting to traders.com.
2: The traders group includes trader1, trader2, and any other user defined in the list.
3: At most, 5,000,000 bytes of data can be in flight on each session.
4: Only one session per connection is allowed.
5: The feeds group includes two users.
6: At most, 1,200,000,000 bytes of data can be in flight on each session.
7: Up to three sessions per connection are allowed.

Chapter 7. Security

7.1. Authenticating Remote Peers

7.2. Setting Up SSL/TLS for Encryption and Authentication

7.3. Setting Up SASL for Authentication and Payload Encryption

7.4. Securing Incoming Connections

7.4.1. Adding SSL/TLS Encryption to an Incoming Connection

7.4.2. Adding SASL Authentication to an Incoming Connection

7.4.3. Adding SSL/TLS Client Authentication to an Incoming Connection

7.4.4. Adding SASL Payload Encryption to an Incoming Connection

7.5. Securing Outgoing Connections

7.5.1. Adding SSL/TLS Client Authentication to an Outgoing Connection

7.5.2. Adding SASL Authentication to an Outgoing Connection

7.6. Integrating with Kerberos

7.7. Authorizing Access to Messaging Resources

7.7.1. Types of Policies

7.7.2. How AMQ Interconnect Applies Policies

7.7.3. Configuring Global Policies

7.7.4. Configuring Vhost Policies

7.7.5. Example: Configuring a Vhost Policy

7.7.6. Example: Using a Vhost Policy to Limit Memory Consumption (Advanced)

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

Making open source more inclusive

About Red Hat

Red Hat legal and privacy links

Red Hat legal and privacy links