EJBCA and Cisco IOS

This guide is contributed by Bruno Bonfils.

The following displays the IOS configuration related to the CA:

!
 crypto ca trustpoint FMSCA
 enrollment url http://your.ca.host.name:8080/ejbca/publicweb/apply/scep
 serial-number
 source interface Ethernet0
 auto-enroll regenerate
 ! 
  • The enrollment line tells how (the method, here an http url) to contact the PKI software. Note that you must omit the pkiclient.exe filename at the end which is automatically add by IOS.
  • The serial-number tells IOS to include the serial number in the request.
  • The name of the trust point you use MUST MATCH exactly the short name of your CA in EJBCA (FMSCA in this example).

Then use the following command to fetch the CA certificate:

# crypto ca authenticate FMSCA  

Next, login to EJBCA, and create a new entity profile according to the following example:

Then, do the password enrollment using the command:

# crypto ca enroll FMSCA

Check your ejbca logs, you should see something like:

ERROR [PKCS10RequestMessage] No CN in DN: SN=12013150+unstructuredName=your.ciscobox.hosts.name
ERROR [Log4jLogDevice] October 19, 2005 9:48:33 AM CEST, CAId : 0, CA, EVENT_ERROR_USERAUTHENTICATION, Administrator : \
PUBLICWEBUSER, IP Address : 192.168.134.1, User : 12013150, Certificate : No Certificate Involved, Comment : \
Got request for nonexisting user: 1201315

So, you know you must add an entity using the serial number as username, the password you define in IOS, and serialNumber/unstructuredNamed as subject DN fields.

After adding the end entity, do the password enrollment again. If you see this you have enrolled successfully:

saroumane#sh crypto ca cert
Certificate
  Status: Available
  Certificate Serial Number: 426FA96340F5D2CA
  Certificate Usage: General Purpose
  Issuer:
    c=FR
    o=Fimasys
    cn=Fimasys Security CA
  Subject:
    Name: your.ciscobox.hosts.name
    Serial Number: 12013150
    serialNumber=12013150
    hostname=your.ciscobox.hosts.name
  Validity Date:
    start date: 08:58:28 CET Oct 19 2005
    end   date: 09:08:28 CET Oct 19 2007
  Associated Trustpoints: FMSCA

CA Certificate
  Status: Available
  Certificate Serial Number: 7AA2B9942CD0D362
  Certificate Usage: Signature
  Issuer:
    c=FR
    o=Fimasys
    cn=Fimasys Security CA
  Subject:
    c=FR
    o=Fimasys
    cn=Fimasys Security CA
  Validity Date:
    start date: 07:29:35 CET Oct 17 2005
    end   date: 07:39:35 CET Oct 15 2015
  Associated Trustpoints: FMSCA  

Cisco IOS Simulator

There is a Cisco 7200 emulator called dynamips available and a graphical front end GNS3.
The following describes how to configure and enroll directly with EJBCA using GNS3 on Ubuntu 8.10:

 sudo apt-get install gns3 uml-utilities bridge-utils 

Note that this requires EJBCA version 3.8.1 or later.

Configure the host and gns3 to be able to communicate with each other, allowing the router can connect to EJBCA on the host computer. This is taken from http://www.blindhog.net/linux-bridging-for-gns3-lan-communications/".

1. Create a tap interface
 sudo tunctl -t tap0
 2. Remove ip addressing and set eth0 and tap0 to promiscuous mode
 sudo ifconfig tap0 0.0.0.0 promisc up
 sudo ifconfig eth0 0.0.0.0 promisc up
 3. Create a new bridge interface
 sudo brctl addbr br0
 4. Add tap0 and eth0 to the bridge group
 sudo brctl addif br0 tap0
 sudo brctl addif br0 eth0
 5. Enable the bridge interface and give it an ip address
 sudo ifconfig br0 up
 sudo ifconfig br0 10.10.10.99/24
 6. Configure the default route
 sudo route add default gw 10.10.10.254 

Start gns3:

 sudo gns3 

Configure with IOS image, for example c7200-jk9s-mz.124-13b.bin (an image with crypto commands), it's available on the net. Also configure a simple topology:

  • drag cloud to topology window
  • drag c7200 to topology window
  • configure cloud and add tap0 interface
  • add manual link from cloud to c7200
  • start c7200
  • open console on c7200
  • enter configuration and configure FastEthernet0/0 with ip 10.10.10.98/255.255.255.0

Now you should be able to ping the host computer, where EJBCA is running.

Next, do the actual enrollment as described above, using the following commands:

 Router>enable
 Router#configure terminal
 Router(config)#
 Router(config)#crypto ca trustpoint ScepCA 
 Router(ca-trustpoint)#enrollment url http://10.10.10.99:8080/ejbca/publicweb/apply/scep
 Router(ca-trustpoint)#serial-number
 Router(ca-trustpoint)#ip-address none
 Router(ca-trustpoint)#subject-name OU=Network Management, O=PrimeKey Solutions AB, C=SE
 Router(ca-trustpoint)#revocation-check none
 Router(ca-trustpoint)#exit 
 Router(config)#crypto ca authenticate ScepCA
 Router(config)#crypto ca enroll ScepCA 

Check the log for the username of the user you must create is called. create end entity profile and user with DN containing SN=FFFFFF and unstructuredName=Router, as seen in the log file (FFFFFF and Router are the default values in the simulator).

Router(config)#crypto ca enroll ScepCA
 Router(config)#exit
 Router#show crypto ca certificate

You can always look at the defined trustpoints using the command:

 Router#show crypto ca trustpoints

If you are enrolling towards an RA instead, issue the following commands (Refer to the External RA documentation for information on how to set up an external RA for SCEP).

Router>enable
 Router#configure terminal
 Router(config)#
 Router(config)#crypto ca trustpoint ScepRA 
 Router(ca-trustpoint)#enrollment url http://10.10.10.99:8080/scepraserver/scep
 Router(ca-trustpoint)#enrollment mode ra
 Router(ca-trustpoint)#serial-number
 Router(ca-trustpoint)#ip-address none
 Router(ca-trustpoint)#subject-name OU=Network Management, O=PrimeKey Solutions AB, C=SE
 Router(ca-trustpoint)#revocation-check none
 Router(ca-trustpoint)#exit 
 Router(config)#crypto ca authenticate ScepRA
 Router(config)#crypto ca enroll ScepRA

Note that this would only have a chance to work in EJBCA 3.8.1 and later, and actually it does not work due to the following error in Cisco. If you have any ideas, please contact us.

 Router#debug crypto pki API
 Router#debug crypto pki messages
 Router#debug crypto pki server
 Router#debug crypto pki transactions
 Router#debug crypto pki validation 
 ... 
 *Jan 16 21:47:32.546: CRYPTO_PKI: make trustedCerts list for ScepRA
 *Jan 16 21:47:32.550: CRYPTO_PKI: subject="c=SE,o=Foo,cn=Scep RA" serial number= 3A 46 2F B4 5B AC 06 47 
 *Jan 16 21:47:32.554: CRYPTO_PKI: subject="c=SE,o=EJBCA Sample,cn=ScepCA" serial number= 19 A6 7D 78 AF 9D 3B 27 
 *Jan 16 21:47:32.566: E ../cert-c/source/p7digdat.c(377) : Error #703h
 *Jan 16 21:47:32.566: E ../cert-c/source/p7spprt.c(589) : Error #703h
 *Jan 16 21:47:32.582: pkcs7 verify data returned status 0x703
 *Jan 16 21:47:32.582: CRYPTO_PKI: status = 1795: failed to verify
 *Jan 16 21:47:32.582: %PKI-6-CERTFAIL: Certificate enrollment failed.
 *Jan 16 21:47:32.582: CRYPTO_PKI: All enrollment requests completed for trustpoint ScepRA.