Hi devs!
I'm working on enhancing a custom 0.8.2.1 producer/consumer to support
establishing connections a secured 0.9.0 cluster with strict ACLs on each
topic. I'm pretty new to (read: first day working with) GSS-API/JAAS and not
really sure how to approach this problem. Our existing implementation is
pretty straight forward, establish a socket to the broker and send/receive byte
arrays conforming to the Kafka protocol accordingly.
Now--with 0.9.0 brokers configured to listen on 9093 with SASL_PLAINTEXT. I'm
performing a auth with Kerberos on our existing Kerberos infrastructure that's
in a known functional state and I'm running into a world of confusion.
My initial experiments consisted of sending a metadata fetch request for a
single topic only that has ACLs restricting metadata, consuming and producing
to only a single principal. Something that should be pretty straight forward.
I'm launching my client with the following system properties configured:
JAVA_OPTS="$JAVA_OPTS -Djavax.security.auth.useSubjectCredsOnly=false"
JAVA_OPTS="$JAVA_OPTS -Djava.security.auth.login.config=$CONFIGDIR/jaas.conf"
JAVA_OPTS="$JAVA_OPTS
-Djava.security.debug=gssloginconfig,configfile,configparser,logincontext"
JAVA_OPTS="$JAVA_OPTS -Djava.security.krb5.realm=MY.REALM"
JAVA_OPTS="$JAVA_OPTS -Djava.security.krb5.kdc=my.kdc"
...and my jaas.conf contains:
com.sun.security.jgss.krb5.initiate {
com.sun.security.auth.module.Krb5LoginModule required
principal="dariens@MY.REALM"
useKeyTab=true
keyTab="/opt/klogger/config/dariens.keytab"
useTicketCache=false
doNotPrompt=true
storeKey=true;
};
I then open the socket as I did with 0.8.2.1 and then use GSS-API to
authenticate myself with a little util that accepts the socket then returns the
GSSContext (code below). I then tried a number of things (being unfamiliar
with everything in this space I relied on trial and error/brute force to
attempt to get it working).
I tried sending/receiving byte arrays as I would have with 0.8.2.1 with
combinations of encrypt/verifyIntegrity, I tried wrapping the original byte
array with the context and sending/verifying the token, all to no avail and
gave up after a number of hours.
FWIW, I do see that I am authenticating via GSS-API properly regardless of what
I then do over the socket.
Could anyone advise how far off my approach is? I'll be reading up on this
more today and have some packet captures that I'll examine to glean more
information on but in the meantime some help would be greatly appreciated!
Logs:
[2015-12-10 14:59:03,716] INFO Listening on port 2002
(com.blackberry.bdp.klogger.TcpListener)
[2015-12-10 14:59:05,408] INFO Creating new producer for topic dariens-only-rw,
key 1 (com.blackberry.bdp.krackle.producer.Producer)
[2015-12-10 14:59:05,624] INFO Updating metadata
(com.blackberry.bdp.krackle.producer.Producer)
[2015-12-10 14:59:05,626] INFO Getting metadata for dariens-only-rw
(com.blackberry.bdp.krackle.meta.MetaData)
[2015-12-10 14:59:05,629] INFO established socket to k1-kafka090.kafka.lab:9093
(com.blackberry.bdp.krackle.meta.MetaData)
[2015-12-10 14:59:05,776] INFO sending token of size 572 from initSecContext
(com.blackberry.bdp.krackle.security.GssKrb5AuthHandler)
[2015-12-10 14:59:05,776] INFO context established
(com.blackberry.bdp.krackle.security.GssKrb5AuthHandler)
[2015-12-10 14:59:05,776] INFO client: dariens@MY.REALM
(com.blackberry.bdp.krackle.security.GssKrb5AuthHandler)
[2015-12-10 14:59:05,776] INFO server: kafka
(com.blackberry.bdp.krackle.security.GssKrb5AuthHandler)
[2015-12-10 14:59:05,776] INFO mutual auth took place?: false
(com.blackberry.bdp.krackle.security.GssKrb5AuthHandler)
[2015-12-10 14:59:05,776] INFO context supports data integrity?: true
(com.blackberry.bdp.krackle.security.GssKrb5AuthHandler)
[2015-12-10 14:59:05,776] INFO context supports data confidentiality?: false
(com.blackberry.bdp.krackle.security.GssKrb5AuthHandler)
configfile: reading file:/opt/klogger/config/jaas.conf
configparser: Reading next config entry: com.sun.security.jgss.krb5.initiate
configparser: com.sun.security.auth.module.Krb5LoginModule, required
configparser: storeKey=true
configparser: useKeyTab=true
configparser: principal=dariens@MY.REALM
configparser: keyTab=/opt/klogger/config/dariens.keytab
configparser: useTicketCache=false
configparser: doNotPrompt=true
[GSS LoginConfigImpl]: Trying com.sun.security.jgss.krb5.initiate: Found!
[LoginContext]: login success
[LoginContext]: commit success
Some GSS-API related source:
public GssKrb5AuthHandler() throws GSSException {
krb5Oid = new Oid("1.2.840.113554.1.2.2");
manager = GSSManager.getInstance();
requestMutualAuth = false;
encrypt = false;
verifyIntegrity = true;
}
public GSSContext getContext(Socket sock,
String peerPrincipal)
throws GSSException, IOException {
DataInputStream inStream = new DataInputStream(sock.getInputStream());
DataOutputStream outStream = new DataOutputStream(sock.getOutputStream());
GSSName peerName = manager.createName(peerPrincipal, null);
GSSContext context = manager.createContext(peerName,
krb5Oid,
null,
GSSContext.DEFAULT_LIFETIME);
context.requestMutualAuth(requestMutualAuth); // Mutual authentication
context.requestConf(encrypt); // Confidentility/encryption
context.requestInteg(verifyIntegrity); // Integrity(i.e. require wrap() and
getMICmethods()
byte[] token = new byte[0];
while (!context.isEstablished()) {
token = context.initSecContext(token, 0, token.length);
if (token != null) {
LOG.info("sending token of size {} from initSecContext", token.length);
outStream.writeInt(token.length);
outStream.write(token);
outStream.flush();
}
if (!context.isEstablished()) {
token = new byte[inStream.readInt()];
LOG.info("read input token (size {}) for processing by initSecContext",
token.length);
inStream.readFully(token);
}
}
LOG.info("context established");
LOG.info("client: {}", context.getSrcName());
LOG.info("server: {} ", context.getTargName());
LOG.info("mutual auth took place?: {}", context.getMutualAuthState());
LOG.info("context supports data integrity?: {}", context.getIntegState());
LOG.info("context supports data confidentiality?: {}",
context.getConfState());
return context;
}
