Zach Miller Computer Sciences Department University of Wisconsin-Madison Securing Condor

Overview › Problems With Default Installation › Security Policy Configuration › Configuring Security Methods › Conclusion and Questions

Problems With Default Installation › Host-based granularity is too big  Any user who can login to central manager has “Administrator” privileges  Any user on a machine can evict the job on that machine via condor_vacate

Problems With Default Installation › Most connections are NOT authenticated  Queue management commands are.  Daemon-to-daemon commands are not.  It is possible to send false information to the collector and other denials of service

Problems With Default Installation › Traffic is not encrypted or checksummed  Possibility of someone eavesdropping on your traffic, including files transferred to or from execute machine  Possibility of someone modifying your traffic without detection

Security Policy Configuration › Condor provides many mechanisms to address the previous shortcomings:  Many authentication methods  Strong encryption  Signed checksums for integrity

Security Policy Configuration › Condor will negotiate security requirements and supported methods client server I want to submit a job You must authenticate w/ kerberos KERBEROS normal submit protocol

Security Policy Configuration Default Policy SEC_DEFAULT_ENCRYPTION = OPTIONAL SEC_DEFAULT_INTEGRITY = OPTIONAL SEC_DEFAULT_AUTHENTICATION = OPTIONAL SEC_DEFAULT_AUTHENTICATION_METHODS = FS, GSI, KERBEROS, SSL, PASSWORD#UNIX SEC_DEFAULT_AUTHENTICATION_METHODS = NTSSPI, KERBEROS, SSL, PASSWORD#WIN32

Security Policy Configuration Default Policy Possible Policy Values NEVERdo not allow this to happen OPTIONALdo not request it, but allow it PREFFEREDrequest it, but do not require it REQUIREDthis is mandatory SEC_DEFAULT_ENCRYPTION = OPTIONAL SEC_DEFAULT_INTEGRITY = OPTIONAL SEC_DEFAULT_AUTHENTICATION = OPTIONAL SEC_DEFAULT_AUTHENTICATION_METHODS = FS, GSI, KERBEROS, SSL, PASSWORD#UNIX SEC_DEFAULT_AUTHENTICATION_METHODS = NTSSPI, KERBEROS, SSL, PASSWORD#WIN32

Security Policy Configuration YYYX YYYN YYNN XNNN R P O N Required Preferred Optional Never Client Policy Server Policy Policy Reconciliation

Security Policy Configuration Very Secure Policy SEC_DEFAULT_ENCRYPTION = REQUIRED SEC_DEFAULT_INTEGRITY = REQUIRED SEC_DEFAULT_AUTHENTICATION = REQUIRED SEC_DEFAULT_AUTHENTICATION_METHODS = SSL SSL CONFIGURATION LATER IN THIS TUTORIAL

Security Policy Configuration Policy Reconciliation Example 1 CLIENT POLICY SEC_DEFAULT_ENCRYPTION = OPTIONAL SEC_DEFAULT_INTEGRITY = OPTIONAL SEC_DEFAULT_AUTHENTICATION = OPTIONAL SEC_DEFAULT_AUTHENTICATION_METHODS = FS, GSI, KERBEROS, SSL, PASSWORD SERVER POLICY SEC_DEFAULT_ENCRYPTION = REQUIRED SEC_DEFAULT_INTEGRITY = REQUIRED SEC_DEFAULT_AUTHENTICATION = REQUIRED SEC_DEFAULT_AUTHENTICATION_METHODS = SSL RECONCILED POLICY ENCRYPTION = YES INTEGRITY = YES AUTHENTICATION = YES METHODS = SSL

Security Policy Configuration Policy Reconciliation Example 2 CLIENT POLICY SEC_DEFAULT_ENCRYPTION = PREFERRED SEC_DEFAULT_INTEGRITY = OPTIONAL SEC_DEFAULT_AUTHENTICATION = REQUIRED SEC_DEFAULT_AUTHENTICATION_METHODS = SSL, GSI, KERBEROS, PASSWORD SERVER POLICY SEC_DEFAULT_ENCRYPTION = NEVER SEC_DEFAULT_INTEGRITY = PREFERRED SEC_DEFAULT_AUTHENTICATION = OPTIONAL SEC_DEFAULT_AUTHENTICATION_METHODS = FS,GSI,SSL RECONCILED POLICY ENCRYPTION = NO INTEGRITY = YES AUTHENTICATION = YES METHODS = GSI,SSL

Security Policy Configuration › As you can see, you may specify a different policy for each authorization level Another Example Policy SEC_DEFAULT_ENCRYPTION = OPTIONAL SEC_DEFAULT_INTEGRITY = PREFERRED SEC_DEFAULT_AUTHENTICATION = REQUIRED SEC_DEFAULT_AUTHENTICATION_METHODS = FS, GSI, KERBEROS, PASSWORD, SSL SEC_READ_INTEGRITY = OPTIONAL SEC_READ_AUTHENTICATION = OPTIONAL SEC_CLIENT_INTEGRITY = OPTIONAL SEC_CLIENT_AUTHENTICATION = OPTIONAL

Security Policy Configuration › Possible values for authorization levels:  CLIENT  READ  WRITE  CONFIG  ADMINISTRATOR  OWNER  DAEMON  NEGOTIATOR

Security Policy Configuration There is now a hierarchy of authorization: READ WRITE DAEMONADMINISTRATOR CONFIG OWNER CLIENT NEGOTIATOR

Security Policy Configuration Once you have authenticated users, you may use a more fine-grained authorization list: ALLOW_WRITE = ALLOW_WRITE = ALLOW_WRITE =

Security Policy Configuration › Format of canonical username: › One wildcard allowed in the portion, and one allowed in the host portion

Security Policy Configuration › Usernames can now be mapped with regular expressions. Old GSI mapfile: “/C=US/ST=Wisconsin/L=Madison/O=University of Wisconsin -- Madison/O=Computer Sciences Department/OU=Condor Project/CN=Zach “/C=US/ST=Wisconsin/L=Madison/O=University of Wisconsin -- Madison/O=Computer Sciences Department/OU=Condor Project/CN=Todd Etc.

Security Policy Configuration › New mapfile applies to all types of authentication › In your condor_config: SEC_CANONICAL_MAPFILE = /path/to/mapfile › Each line is a mapping rule

Security Policy Configuration › Sample map file: CLAIMTOBE.*nobody FS(.*)\1 GSI =(.*)\1

Security Policy Configuration › Review:  The security policy determines which types of security mechanism will be used for a given type of command: SEC_ADMINISTRATOR_AUTHENTICATION = REQUIRED SEC_ADMINISTRATOR_AUTHENTICATION_METHODS = GSI

Security Policy Configuration › Review:  The map file gives you a canonical name from the authenticated user: GSI =(.*)\1 “/C=US/ST=Wisconsin/L=Madison/O=University of Wisconsin – Madison/O=Computer Sciences Department/OU=Condor Project /CN=Zach

Security Policy Configuration › Review:  The ALLOW_ and DENY_ lists control the authorization of the canonical users: ALLOW_WRITE = DENY_WRITE = *.evildomain.net

Configuring Security Methods CLAIMTOBE is not configurable, and is meant for testing purposes only. ANONYMOUS is also not configurable, and always sends the username “CONDOR_ANONYMOUS”

Configuring Security Methods FS works by creating a file in /tmp, and checking to see who the owner of that file is. FS_REMOTE is similar, but allows you to specify where to create the file, allowing you to use a directory on NFS or some other shared storage. This is specified like so: FS_REMOTE_DIR = /shared/temp/space

Configuring Security Methods NTSSPI uses Windows’ SSPI authentication. This requires that the username and password be the same on two machines that are authenticating to each other. There are no configuration options for this method.

Configuring Security Methods GSI is the Globus Toolkit’s implementation of X.509. There are quite a number of configuration options for this which essentially specify which credentials to use, which to expect, and who is allowed to sign the credentials.

Configuring Security Methods When using GSI, a user typically has a public key (certificate) and a private key that is encrypted with a password. A temporary certificate, called a proxy, is created for use with condor: % grid-proxy-init -cert zmiller.crt -key zmiller.key Your identity: /C=US/ST=Wisconsin/L=Madison/O=University of Wisconsin -- Madison/O=Computer Sciences Department/OU=Condor Project/CN=Zach Enter GRID pass phrase for this identity: Creating proxy Done

Configuring Security Methods For the Condor daemons to use GSI authentication, however, they will need either a proxy or a private key with no password. Proxies would need to be valid for a considerable length of time to be useful in this context, so usually a cert/keypair is used.

Configuring Security Methods GSI_DAEMON_CERT = condor_cred.crt GSI_DAEMON_KEY = condor_cred.key Also, Condor needs to know the public key of any CA that signs certificates: GSI_DAEMON_TRUSTED_CA_DIR=/path/to/keys

Configuring Security Methods Typically, there is a “host credential” which is owned by root in: /etc/grid-security/host.crt /etc/grid-security/host.key And also a directory of signing keys in /etc/grid-security/certificates

Configuring Security Methods Condor will use those defaults without any additional configuration, if it has root privilege to read the host key. Alternatively, you can specify your own directory to hold the key files and the signing certificates by using: GSI_DAEMON_DIRECTORY=~/globus/

Configuring Security Methods Since GSI is currently available only on UNIX systems, we have also added support for OpenSSL. It needs essentially the same information as GSI, which is specified in this case with a different set of configuration parameters: AUTH_SSL_SERVER_CAFILE AUTH_SSL_SERVER_CADIR AUTH_SSL_SERVER_CERTFILE AUTH_SSL_SERVER_KEYFILE AUTH_SSL_CLIENT_CAFILE AUTH_SSL_CLIENT_CADIR AUTH_SSL_CLIENT_CERTFILE AUTH_SSL_CLIENT_KEYFILE

Configuring Security Methods For both GSI and OpenSSL, you can use the openssl command line tool to create all the necessary keys and files. For more detailed info on that, please see the openssl man page, or come to the security BOF 1:30.

Configuring Security Methods KERBEROS is now available on both UNIX and Windows platforms On UNIX, it authenticates again a KDC (Kerberos Domain Controller). On Windows, the Active Directory server fills this role.

Configuring Security Methods For Kerberos, a user may need to run kinit if that is not part of the normal login process: % kinit Password for % klist Ticket cache: FILE:/var/adm/krb5/tmp/tkt/tkt_24842_pid14957 Default principal: Valid starting Expires Service principal 04/24/06 12:01:07 05/24/06

Configuring Security Methods The Condor daemons can use the “host credential” if they are running as root. The default keytab file is typically in /etc/v5srvtab Alternatively, you can specify your own keytab file and server principal to use: KERBEROS_SERVER_KEYTAB = /scratch/zmiller/keytab.zmiller KERBEROS_SERVER_PRINCIPAL =

Configuring Security Methods PASSWORD authentication also works on both UNIX and Windows, although the interface is somewhat different. On Windows, the password is stored in a secure part of the registry. On UNIX, the password is stored in a file specified by: SEC_PASSWORD_FILE = /path/to/file

Configuring Security Methods To set the pool password, use the condor_store_cred command: condor_store_cred add –p password

Conclusion Now you have seen a general overview of the different methods that Condor supports, how to configure them, and how to set policy so they get used where you want them.

Questions? Also, security BOF 2:30!