Table Of Contents
Implementing Keychain Management on Cisco IOS XR Software
Contents
Restrictions for Implementing Keychain Management
Information About Implementing Keychain Management
Lifetime of a Key
How to Implement Keychain Management
Configuring a Keychain
What to Do Next
Configuring a Tolerance Specification to Accept Keys
Configuring a Key Identifier for the Keychain
What to Do Next
Configuring the Text for the Key String
What to Do Next
Determining the Valid Keys
Configuring the Keys to Generate Authentication Digest for the Outbound Application Traffic
Configuring the Cryptographic Algorithm
Configuration Examples for Implementing Keychain Management
Configuring Keychain Management: Example
Additional References
Related Documents
Standards
MIBs
RFCs
Technical Assistance
Implementing Keychain Management on Cisco IOS XR Software
Keychain management is a common method of authentication to configure shared secrets on all the entities, which exchange secrets such as keys before establishing trust with each other. Routing protocols and network management applications on Cisco IOS XR software often use authentication to enhance security while communicating with peers.
Feature History for Implementing Keychain Management on Cisco IOS XR Software
Release
|
Modification
|
Release 3.3.0
|
This feature was introduced on Cisco CRS-1 and Cisco XR 12000 Series Router.
|
Release 3.4.0
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• Support for the MAC authentication algorithm was added.
•Support for hitless key rollover and key acceptance tolerance were added.
|
Contents
•Restrictions for Implementing Keychain Management
•Information About Implementing Keychain Management
•How to Implement Keychain Management
•Configuration Examples for Implementing Keychain Management
•Additional References
Restrictions for Implementing Keychain Management
You must be aware that changing the system clock impacts the validity of the keys in the existing configuration.
Information About Implementing Keychain Management
The keychain by itself has no relevance; therefore, it must be used by an application that needs to communicate by using the keys (for authentication) with its peers. The keychain provides a secure mechanism to handle the keys and rollover based on the lifetime. Border Gateway Protocol (BGP) uses the keychain to implement a hitless key rollover for authentication.
BGP uses TCP authentication, which enables the authentication option and sends the Message Authentication Code (MAC) based on the cryptographic algorithm configured for the keychain.
To implement keychain management, you must understand the following concepts:
•Lifetime of a Key
Lifetime of a Key
If you are using keys as the security method, you must specify the lifetime for the keys and change the keys on a regular basis when they expire. To maintain stability, each party must be able to store and use more than one key for an application at the same time. A keychain is a sequence of keys that are collectively managed for authenticating the same peer, peer group, or both.
Keychain management groups a sequence of keys together under a keychain and associates each key in the keychain with a lifetime.
Note Any key that is configured without a lifetime is considered invalid; therefore, the key is rejected during configuration.
The lifetime of a key is defined by the following options:
•Start-time—Specifies the absolute time.
•End-time—Specifies the absolute time that is relative to the start-time or infinite time.
Each key definition within the keychain must specify a time interval for which that key is activated; for example, lifetime. Then, during a given key's lifetime, routing update packets are sent with this activated key. Keys cannot be used during time periods for which they are not activated. Therefore, we recommend that for a given keychain, key activation times overlap to avoid any period of time for which no key is activated. If a time period occurs during which no key is activated, neighbor authentication cannot occur; therefore, routing updates can fail.
Multiple keychains can be specified.
How to Implement Keychain Management
This section contains the following procedures:
•Configuring a Keychain (required)
•Configuring a Tolerance Specification to Accept Keys (required)
•Configuring a Key Identifier for the Keychain (required)
•Configuring the Text for the Key String (required)
•Determining the Valid Keys (optional)
•Configuring the Keys to Generate Authentication Digest for the Outbound Application Traffic (required)
•Configuring the Cryptographic Algorithm (required)
Configuring a Keychain
This task configures a name for the keychain.
You can create or modify the name of the keychain.
SUMMARY STEPS
1. configure
2. key chain key-chain-name
3. end
or
commit
4. show key chain key-chain-name
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
RP/0/RP0/CPU0:router# configure
|
Enters global configuration mode.
|
Step 2
|
key chain key-chain-name
Example:
RP/0/RP0/CPU0:router(config)# key chain
isis-keys
RP/0/RP0/CPU0:router(config-isis-keys)#
|
Creates a name for the keychain.
Note Configuring only the keychain name without any key identifiers is considered a nonoperation. When you exit the configuration, the router does not prompt you to commit changes until you have configured the key identifier and at least one of the global configuration mode or keychain-key configuration mode (for example, lifetime or key string).
|
Step 3
|
end
or
commit
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# end
or
RP/0/RP0/CPU0:router(config-isis-keys)# commit
|
Saves configuration changes.
•When you issue the end command, the system prompts you to commit changes:
Uncommitted changes found, commit them before
exiting(yes/no/cancel)?
[cancel]:
–Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.
–Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.
–Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.
•Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.
|
Step 4
|
show key chain key-chain-name
Example:
RP/0/RP0/CPU0:router# show key chain isis-keys
|
(Optional) Displays the name of the keychain.
Note The key-chain-name argument is optional. If you do not specify a name for the key-chain-name argument, all the keychains are displayed.
|
What to Do Next
After completing keychain configuration, see the Configuring a Tolerance Specification to Accept Keys section.
Configuring a Tolerance Specification to Accept Keys
This task configures the tolerance specification to accept keys for a keychain to facilitate a hitless key rollover for applications, such as routing and management protocols.
SUMMARY STEPS
1. configure
2. key chain key-chain-name
3. accept-tolerance [value | infinite]
4. end
or
commit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
RP/0/RP0/CPU0:router# configure
|
Enters global configuration mode.
|
Step 2
|
key chain key-chain-name
Example:
RP/0/RP0/CPU0:router(config)# key chain isis-keys
|
Creates a name for the keychain.
|
Step 3
|
accept-tolerance [value | infinite]
Example:
RP/0/RP0/CPU0:router(config-isis-keys)#
accept-tolerance infinite
|
Configures a tolerance value to accept keys for the keychain.
•Use the value argument to set the tolerance range in seconds. The range is from 1 to 8640000.
•Use the infinite keyword to specify that the tolerance specification is infinite.
|
Step 4
|
end
or
commit
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# end
or
RP/0/RP0/CPU0:router(config-isis-keys)# commit
|
Saves configuration changes.
•When you issue the end command, the system prompts you to commit changes:
Uncommitted changes found, commit them
before exiting(yes/no/cancel)?
[cancel]:
–Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.
–Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.
–Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.
•Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.
|
Configuring a Key Identifier for the Keychain
This task configures a key identifier for the keychain.
You can create or modify the key for the keychain.
SUMMARY STEPS
1. configure
2. key chain key-chain-name
3. key key-id
4. end
or
commit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
RP/0/RP0/CPU0:router# configure
|
Enters global configuration mode.
|
Step 2
|
key chain key-chain-name
Example:
RP/0/RP0/CPU0:router(config)# key chain
isis-keys
|
Creates a name for the keychain.
|
Step 3
|
key key-id
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# key 8
|
Creates a key for the keychain. The key ID number is translated from decimal to hexadecimal to create the command mode subprompt.
|
Step 4
|
end
or
commit
Example:
RP/0/RP0/CPU0:router(config-isis-keys-0x8)# end
or
RP/0/RP0/CPU0:router(config-isis-keys-0x8)#
commit
|
Saves configuration changes.
•When you issue the end command, the system prompts you to commit changes:
Uncommitted changes found, commit them before
exiting(yes/no/cancel)?
[cancel]:
–Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.
–Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.
–Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.
•Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.
|
What to Do Next
After configuring a key identifier for the keychain, see the Configuring the Text for the Key String section.
Configuring the Text for the Key String
This task configures the text for the key string.
SUMMARY STEPS
1. configure
2. key chain key-chain-name
3. key key-id
4. key-string [clear | password] key-string-text
5. end
or
commit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
RP/0/RP0/CPU0:router# configure
|
Enters global configuration mode.
|
Step 2
|
key chain key-chain-name
Example:
RP/0/RP0/CPU0:router(config)# key chain
isis-keys
|
Creates a name for the keychain.
|
Step 3
|
key key-id
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# key 8
RP/0/RP0/CPU0:router(config-isis-keys-0x8)#
|
Creates a key for the keychain.
|
Step 4
|
key-string [clear | password] key-string-text
Example:
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)#
key-string password 8
|
Specifies the text string for the key.
•Use the clear keyword to specify the key string in clear text form; use the password keyword to specify the key in encrypted form.
|
Step 5
|
end
or
commit
Example:
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)# end
or
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)#
commit
|
Saves configuration changes.
•When you issue the end command, the system prompts you to commit changes:
Uncommitted changes found, commit them before
exiting(yes/no/cancel)?
[cancel]:
–Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.
–Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.
–Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.
•Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.
|
What to Do Next
After configuring the text for the key string, see the Configuring the Keys to Generate Authentication Digest for the Outbound Application Traffic section.
Determining the Valid Keys
This task determines the valid keys for local applications to authenticate the remote peers.
SUMMARY STEPS
1. configure
2. key chain key-chain-name
3. key key-id
4. accept-lifetime start-time [duration durationvalue | infinite | end-time]
5. end
or
commit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
RP/0/RP0/CPU0:router# configure
|
Enters global configuration mode.
|
Step 2
|
key chain key-chain-name
Example:
RP/0/RP0/CPU0:router(config)# key chain
isis-keys
|
Creates a a name for the keychain.
|
Step 3
|
key key-id
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# key 8
RP/0/RP0/CPU0:router(config-isis-keys-0x8)#
|
Creates a key for the keychain.
|
Step 4
|
accept-lifetime start-time [duration
durationvalue | infinite | end-time]
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# key 8
RP/0/RP0/CPU0:router(config-isis-keys-0x8)#
accept-lifetime 1:00:00 october 24 2005
infinite
|
(Optional) Specifies the validity of the key lifetime in terms of clock time.
|
Step 5
|
end
or
commit
Example:
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)# end
or
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)#
commit
|
Saves configuration changes.
•When you issue the end command, the system prompts you to commit changes:
Uncommitted changes found, commit them before
exiting(yes/no/cancel)?
[cancel]:
–Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.
–Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.
–Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.
•Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.
|
Configuring the Keys to Generate Authentication Digest for the Outbound Application Traffic
This task configures the keys to generate authentication digest for the outbound application traffic.
SUMMARY STEPS
1. configure
2. key chain key-chain-name
3. key key-id
4. send-lifetime start-time [duration durationvalue | infinite | end-time]
5. end
or
commit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
RP/0/RP0/CPU0:router# configure
|
Enters global configuration mode.
|
Step 2
|
key chain key-chain-name
Example:
RP/0/RP0/CPU0:router(config)# key chain
isis-keys
|
Creates a name for the keychain.
|
Step 3
|
key key-id
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# key 8
RP/0/RP0/CPU0:router(config-isis-keys-0x8)#
|
Creates a key for the keychain.
|
Step 4
|
send-lifetime start-time [duration
durationvalue | infinite | end-time]
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# key 8
RP/0/RP0/CPU0:router(config-isis-keys-0x8)#
send-lifetime 1:00:00 october 24 2005 infinite
|
(Optional) Specifies the set time period during which an authentication key on a keychain is valid to be sent. You can specify the validity of the key lifetime in terms of clock time.
In addition, you can specify a start-time value and one of the following values:
•duration keyword (seconds)
•infinite keyword
•end-time argument
If you intend to set lifetimes on keys, Network Time Protocol (NTP) or some other time synchronization method is recommended.
|
Step 5
|
end
or
commit
Example:
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)# end
or
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)#
commit
|
Saves configuration changes.
•When you issue the end command, the system prompts you to commit changes:
Uncommitted changes found, commit them before
exiting(yes/no/cancel)?
[cancel]:
–Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.
–Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.
–Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.
•Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.
|
Configuring the Cryptographic Algorithm
This task allows the keychain configuration to accept the choice of the cryptographic algorithm.
SUMMARY STEPS
1. configure
2. key chain key-chain-name
3. key key-id
4. cryptographic-algorithm [HMAC-MD5 | HMAC-SHA1-12 | HMAC-SHA1-20 | MD5 | SHA-1]
5. end
or
commit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
RP/0/RP0/CPU0:router# configure
|
Enters global configuration mode.
|
Step 2
|
key chain key-chain-name
Example:
RP/0/RP0/CPU0:router(config)# key chain isis-keys
RP/0/RP0/CPU0:router(config-isis-keys)#
|
Creates a name for the keychain.
|
Step 3
|
key key-id
Example:
RP/0/RP0/CPU0:router(config-isis-keys)# key 8
RP/0/RP0/CPU0:router(config-isis-keys-0x8)#
|
Creates a key for the keychain.
|
Step 4
|
cryptographic-algorithm [HMAC-MD5 | HMAC-SHA1-12 |
HMAC-SHA1-20 | MD5 | SHA-1]
Example:
RP/0/RP0/CPU0:router(config-isis-keys-0x8)#
cryptographic-algorithm MD5
|
Specifies the choice of the cryptographic algorithm. You can choose from the following list of algorithms:
•HMAC-MD5
•HMAC-SHA1-12
•HMAC-SHA1-20
•MD5
•SHA-1
|
Step 5
|
end
or
commit
Example:
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)# end
or
RP/0/RP0/CPU0:myhost(config-isis-keys-0x8)# commit
|
Saves configuration changes.
•When you issue the end command, the system prompts you to commit changes:
Uncommitted changes found, commit them
before exiting(yes/no/cancel)?
[cancel]:
–Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.
–Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.
–Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.
•Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.
|
Configuration Examples for Implementing Keychain Management
This section provides the following configuration example:
•Configuring Keychain Management: Example
Configuring Keychain Management: Example
The following example shows how to configure keychain management:
accept-tolerance infinite
cryptographic-algorithm MD5
send-lifetime 1:00:00 june 29 2006 infinite
accept-lifetime 1:00:00 june 29 2006 infinite
Uncommitted changes found, commit them? [yes]: yes
accept-tolerance -- infinite
Key 8 -- text "1104000E120B520005282820"
cryptographic-algorithm -- MD5
Send lifetime: 01:00:00, 29 Jun 2006 - Always valid [Valid now]
Accept lifetime: 01:00:00, 29 Jun 2006 - Always valid [Valid now]
Additional References
The following sections provide references related to implementing keychain management.
Related Documents
Related Topic
|
Document Title
|
Keychain management commands: complete command syntax, command modes, command history, defaults, usage guidelines, and examples
|
Keychain Management Commands on Cisco IOS XR Software
|
Standards
Standards
|
Title
|
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.
|
—
|
MIBs
RFCs
RFCs
|
Title
|
No new or modified RFCs are supported by this feature.
|
—
|
Technical Assistance
Description
|
Link
|
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|
http://www.cisco.com/techsupport
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