Detta är heimdal.info, skapad av makeinfo version 4.8 från heimdal.texi. INFO-DIR-SECTION Security START-INFO-DIR-ENTRY * Heimdal: (heimdal). The Kerberos 5 distribution from KTH END-INFO-DIR-ENTRY  File: heimdal.info, Node: Top, Next: Introduction, Prev: (dir), Up: (dir) Heimdal ******* This manual for version 1.5.1 of Heimdal. * Menu: * Introduction:: * What is Kerberos?:: * Building and Installing:: * Setting up a realm:: * Applications:: * Things in search for a better place:: * Kerberos 4 issues:: * Windows compatibility:: * Programming with Kerberos:: * Migration:: * Acknowledgments:: * Copyrights and Licenses:: --- The Detailed Node Listing --- Setting up a realm * Configuration file:: * Creating the database:: * Modifying the database:: * keytabs:: * Serving Kerberos 4/524/kaserver:: * Remote administration:: * Password changing:: * Testing clients and servers:: * Slave Servers:: * Incremental propagation:: * Encryption types and salting:: * Credential cache server - KCM:: * Cross realm:: * Transit policy:: * Setting up DNS:: * Using LDAP to store the database:: * Providing Kerberos credentials to servers and programs:: * Setting up PK-INIT:: Applications * Authentication modules:: * AFS:: Authentication modules * Digital SIA:: * IRIX:: Kerberos 4 issues * Principal conversion issues:: * Converting a version 4 database:: * kaserver:: Windows compatibility * Configuring Windows to use a Heimdal KDC:: * Inter-Realm keys (trust) between Windows and a Heimdal KDC:: * Create account mappings:: * Encryption types:: * Authorisation data:: * Quirks of Windows 2000 KDC:: * Useful links when reading about the Windows:: Programming with Kerberos  File: heimdal.info, Node: Introduction, Next: What is Kerberos?, Prev: Top, Up: Top 1 Introduction ************** What is Heimdal? ================ Heimdal is a free implementation of Kerberos 5. The goals are to: * have an implementation that can be freely used by anyone * be protocol compatible with existing implementations and, if not in conflict, with RFC 4120 (and any future updated RFC). RFC 4120 replaced RFC 1510. * be reasonably compatible with the M.I.T Kerberos V5 API * have support for Kerberos V5 over GSS-API (RFC1964) * include the most important and useful application programs (rsh, telnet, popper, etc.) * include enough backwards compatibility with Kerberos V4 Status ====== Heimdal has the following features (this does not mean any of this works): * a stub generator and a library to encode/decode/whatever ASN.1/DER stuff * a `libkrb5' library that should be possible to get to work with simple applications * a GSS-API library * `kinit', `klist', `kdestroy' * `telnet', `telnetd' * `rsh', `rshd' * `popper', `push' (a movemail equivalent) * `ftp', and `ftpd' * a library `libkafs' for authenticating to AFS and a program `afslog' that uses it * some simple test programs * a KDC that supports most things; optionally, it may also support Kerberos V4 and kaserver, * simple programs for distributing databases between a KDC master and slaves * a password changing daemon `kpasswdd', library functions for changing passwords and a simple client * some kind of administration system * Kerberos V4 support in many of the applications. Bug reports =========== If you find bugs in this software, make sure it is a genuine bug and not just a part of the code that isn't implemented. Bug reports should be sent to . Please include information on what machine and operating system (including version) you are running, what you are trying to do, what happens, what you think should have happened, an example for us to repeat, the output you get when trying the example, and a patch for the problem if you have one. Please make any patches with `diff -u' or `diff -c'. Suggestions, comments and other non bug reports are also welcome. Mailing list ============ There are two mailing lists with talk about Heimdal. is a low-volume announcement list, while is for general discussion. Send a message to to subscribe. Heimdal source code, binaries and the manual ============================================ The source code for heimdal, links to binaries and the manual (this document) can be found on our web-page at `http://www.pdc.kth.se/heimdal/'.  File: heimdal.info, Node: What is Kerberos?, Next: Building and Installing, Prev: Introduction, Up: Top 2 What is Kerberos? ******************* Now this Cerberus had three heads of dogs, the tail of a dragon, and on his back the heads of all sorts of snakes. -- Pseudo-Apollodorus Library 2.5.12 Kerberos is a system for authenticating users and services on a network. It is built upon the assumption that the network is "unsafe". For example, data sent over the network can be eavesdropped and altered, and addresses can also be faked. Therefore they cannot be used for authentication purposes. Kerberos is a trusted third-party service. That means that there is a third party (the kerberos server) that is trusted by all the entities on the network (users and services, usually called "principals"). All principals share a secret password (or key) with the kerberos server and this enables principals to verify that the messages from the kerberos server are authentic. Thus trusting the kerberos server, users and services can authenticate each other. 2.1 Basic mechanism =================== *Note* This discussion is about Kerberos version 4, but version 5 works similarly. In Kerberos, principals use "tickets" to prove that they are who they claim to be. In the following example, A is the initiator of the authentication exchange, usually a user, and B is the service that A wishes to use. To obtain a ticket for a specific service, A sends a ticket request to the kerberos server. The request contains A's and B's names (along with some other fields). The kerberos server checks that both A and B are valid principals. Having verified the validity of the principals, it creates a packet containing A's and B's names, A's network address (A), the current time (T), the lifetime of the ticket (LIFE), and a secret "session key" (K). This packet is encrypted with B's secret key (K). The actual ticket (T) looks like this: ({A, B, A, T, LIFE, K}K). The reply to A consists of the ticket (T), B's name, the current time, the lifetime of the ticket, and the session key, all encrypted in A's secret key ({B, T, LIFE, K, T}K). A decrypts the reply and retains it for later use. Before sending a message to B, A creates an authenticator consisting of A's name, A's address, the current time, and a "checksum" chosen by A, all encrypted with the secret session key ({A, A, T, CHECKSUM}K). This is sent together with the ticket received from the kerberos server to B. Upon reception, B decrypts the ticket using B's secret key. Since the ticket contains the session key that the authenticator was encrypted with, B can now also decrypt the authenticator. To verify that A really is A, B now has to compare the contents of the ticket with that of the authenticator. If everything matches, B now considers A as properly authenticated. 2.2 Different attacks ===================== Impersonating A --------------- An impostor, C could steal the authenticator and the ticket as it is transmitted across the network, and use them to impersonate A. The address in the ticket and the authenticator was added to make it more difficult to perform this attack. To succeed C will have to either use the same machine as A or fake the source addresses of the packets. By including the time stamp in the authenticator, C does not have much time in which to mount the attack. Impersonating B --------------- C can hijack B's network address, and when A sends her credentials, C just pretend to verify them. C can't be sure that she is talking to A. 2.3 Defence strategies ====================== It would be possible to add a "replay cache" to the server side. The idea is to save the authenticators sent during the last few minutes, so that B can detect when someone is trying to retransmit an already used message. This is somewhat impractical (mostly regarding efficiency), and is not part of Kerberos 4; MIT Kerberos 5 contains it. To authenticate B, A might request that B sends something back that proves that B has access to the session key. An example of this is the checksum that A sent as part of the authenticator. One typical procedure is to add one to the checksum, encrypt it with the session key and send it back to A. This is called "mutual authentication". The session key can also be used to add cryptographic checksums to the messages sent between A and B (known as "message integrity"). Encryption can also be added ("message confidentiality"). This is probably the best approach in all cases. 2.4 Further reading =================== The original paper on Kerberos from 1988 is `Kerberos: An Authentication Service for Open Network Systems', by Jennifer Steiner, Clifford Neuman and Jeffrey I. Schiller. A less technical description can be found in `Designing an Authentication System: a Dialogue in Four Scenes' by Bill Bryant, also from 1988. These documents can be found on our web-page at `http://www.pdc.kth.se/kth-krb/'.  File: heimdal.info, Node: Building and Installing, Next: Setting up a realm, Prev: What is Kerberos?, Up: Top 3 Building and Installing ************************* Build and install instructions are located here: `http://www.h5l.org/compile.html' Prebuilt packages is located here: `http://www.h5l.org/binaries.html'  File: heimdal.info, Node: Setting up a realm, Next: Applications, Prev: Building and Installing, Up: Top 4 Setting up a realm ******************** A realm is an administrative domain. The name of a Kerberos realm is usually the Internet domain name in uppercase. Call your realm the same as your Internet domain name if you do not have strong reasons for not doing so. It will make life easier for you and everyone else. * Menu: * Configuration file:: * Creating the database:: * Modifying the database:: * Checking the setup:: * keytabs:: * Serving Kerberos 4/524/kaserver:: * Remote administration:: * Password changing:: * Testing clients and servers:: * Slave Servers:: * Incremental propagation:: * Encryption types and salting:: * Credential cache server - KCM:: * Cross realm:: * Transit policy:: * Setting up DNS:: * Using LDAP to store the database:: * Providing Kerberos credentials to servers and programs:: * Setting up PK-INIT:: * Debugging Kerberos problems::  File: heimdal.info, Node: Configuration file, Next: Creating the database, Prev: Setting up a realm, Up: Setting up a realm 4.1 Configuration file ====================== To setup a realm you will first have to create a configuration file: `/etc/krb5.conf'. The `krb5.conf' file can contain many configuration options, some of which are described here. There is a sample `krb5.conf' supplied with the distribution. The configuration file is a hierarchical structure consisting of sections, each containing a list of bindings (either variable assignments or subsections). A section starts with `[`section-name']'. A binding consists of a left hand side, an equal sign (`=') and a right hand side (the left hand side tag must be separated from the equal sign with some whitespace). Subsections have a `{' as the first non-whitespace character after the equal sign. All other bindings are treated as variable assignments. The value of a variable extends to the end of the line. [section1] a-subsection = { var = value1 other-var = value with {} sub-sub-section = { var = 123 } } var = some other value [section2] var = yet another value In this manual, names of sections and bindings will be given as strings separated by slashes (`/'). The `other-var' variable will thus be `section1/a-subsection/other-var'. For in-depth information about the contents of the configuration file, refer to the `krb5.conf' manual page. Some of the more important sections are briefly described here. The `libdefaults' section contains a list of library configuration parameters, such as the default realm and the timeout for KDC responses. The `realms' section contains information about specific realms, such as where they hide their KDC. This section serves the same purpose as the Kerberos 4 `krb.conf' file, but can contain more information. Finally the `domain_realm' section contains a list of mappings from domains to realms, equivalent to the Kerberos 4 `krb.realms' file. To continue with the realm setup, you will have to create a configuration file, with contents similar to the following. [libdefaults] default_realm = MY.REALM [realms] MY.REALM = { kdc = my.kdc my.slave.kdc kdc = my.third.kdc kdc = 130.237.237.17 kdc = [2001:6b0:1:ea::100]:88 } [domain_realm] .my.domain = MY.REALM If you use a realm name equal to your domain name, you can omit the `libdefaults', and `domain_realm', sections. If you have a DNS SRV-record for your realm, or your Kerberos server has DNS CNAME `kerberos.my.realm', you can omit the `realms' section too. If you want to use a different configuration file then the default you can point a file with the enviroment variable `KRB5_CONFIG'. env KRB5_CONFIG=$HOME/etc/krb5.conf kinit user@REALM  File: heimdal.info, Node: Creating the database, Next: Modifying the database, Prev: Configuration file, Up: Setting up a realm 4.2 Creating the database ========================= The database library will look for the database in the directory `/var/heimdal', so you should probably create that directory. Make sure the directory has restrictive permissions. # mkdir /var/heimdal The keys of all the principals are stored in the database. If you choose to, these can be encrypted with a master key. You do not have to remember this key (or password), but just to enter it once and it will be stored in a file (`/var/heimdal/m-key'). If you want to have a master key, run `kstash' to create this master key: # kstash Master key: Verifying password - Master key: If you want to generate a random master key you can use the `--random-key' flag to kstash. This will make sure you have a good key on which attackers can't do a dictionary attack. If you have a master key, make sure you make a backup of your master key file; without it backups of the database are of no use. To initialise the database use the `kadmin' program, with the `-l' option (to enable local database mode). First issue a `init MY.REALM' command. This will create the database and insert default principals for that realm. You can have more than one realm in one database, so `init' does not destroy any old database. Before creating the database, `init' will ask you some questions about maximum ticket lifetimes. After creating the database you should probably add yourself to it. You do this with the `add' command. It takes as argument the name of a principal. The principal should contain a realm, so if you haven't set up a default realm, you will need to explicitly include the realm. # kadmin -l kadmin> init MY.REALM Realm max ticket life [unlimited]: Realm max renewable ticket life [unlimited]: kadmin> add me Max ticket life [unlimited]: Max renewable life [unlimited]: Attributes []: Password: Verifying password - Password: Now start the KDC and try getting a ticket. # kdc & # kinit me me@MY.REALMS's Password: # klist Credentials cache: /tmp/krb5cc_0 Principal: me@MY.REALM Issued Expires Principal Aug 25 07:25:55 Aug 25 17:25:55 krbtgt/MY.REALM@MY.REALM If you are curious you can use the `dump' command to list all the entries in the database. It should look something similar to the following example (note that the entries here are truncated for typographical reasons): kadmin> dump me@MY.REALM 1:0:1:0b01d3cb7c293b57:-:0:7:8aec316b9d1629e3baf8 ... kadmin/admin@MY.REALM 1:0:1:e5c8a2675b37a443:-:0:7:cb913ebf85 ... krbtgt/MY.REALM@MY.REALM 1:0:1:52b53b61c875ce16:-:0:7:c8943be ... kadmin/changepw@MY.REALM 1:0:1:f48c8af2b340e9fb:-:0:7:e3e6088 ...  File: heimdal.info, Node: Modifying the database, Next: Checking the setup, Prev: Creating the database, Up: Setting up a realm 4.3 Modifying the database ========================== All modifications of principals are done with with kadmin. A principal has several attributes and lifetimes associated with it. Principals are added, renamed, modified, and deleted with the kadmin commands `add', `rename', `modify', `delete'. Both interactive editing and command line flags can be used (use -help to list the available options). There are different kinds of types for the fields in the database; attributes, absolute time times and relative times. 4.3.1 Attributes ---------------- When doing interactive editing, attributes are listed with `?'. The attributes are given in a comma (`,') separated list. Attributes are removed from the list by prefixing them with `-'. kadmin> modify me Max ticket life [1 day]: Max renewable life [1 week]: Principal expiration time [never]: Password expiration time [never]: Attributes [disallow-renewable]: requires-pre-auth,-disallow-renewable kadmin> get me Principal: me@MY.REALM [...] Attributes: requires-pre-auth 4.3.2 Absolute times -------------------- The format for absolute times are any of the following: never now YYYY-mm-dd YYYY-mm-dd HH:MM:SS 4.3.3 Relative times -------------------- The format for relative times are any of the following combined: N year M month O day P hour Q minute R second  File: heimdal.info, Node: Checking the setup, Next: keytabs, Prev: Modifying the database, Up: Setting up a realm 4.4 Checking the setup ====================== There are two tools that can check the consistency of the Kerberos configuration file and the Kerberos database. The Kerberos configuration file is checked using `verify_krb5_conf'. The tool checks for common errors, but commonly there are several uncommon configuration entries that are never added to the tool and thus generates "unknown entry" warnings. This is usually nothing to worry about. The database check is built into the kadmin tool. It will check for common configuration error that will cause problems later. Common check are for existence and flags on important principals. The database check by run by the following command : kadmin -l check REALM.EXAMPLE.ORG  File: heimdal.info, Node: keytabs, Next: Serving Kerberos 4/524/kaserver, Prev: Checking the setup, Up: Setting up a realm 4.5 keytabs =========== To extract a service ticket from the database and put it in a keytab, you need to first create the principal in the database with `add' (using the `--random-key' flag to get a random key) and then extract it with `ext_keytab'. kadmin> add --random-key host/my.host.name Max ticket life [unlimited]: Max renewable life [unlimited]: Attributes []: kadmin> ext host/my.host.name kadmin> exit # ktutil list Version Type Principal 1 des-cbc-md5 host/my.host.name@MY.REALM 1 des-cbc-md4 host/my.host.name@MY.REALM 1 des-cbc-crc host/my.host.name@MY.REALM 1 des3-cbc-sha1 host/my.host.name@MY.REALM  File: heimdal.info, Node: Serving Kerberos 4/524/kaserver, Next: Remote administration, Prev: keytabs, Up: Setting up a realm 4.6 Serving Kerberos 4/524/kaserver =================================== Heimdal can be configured to support 524, Kerberos 4 or kaserver. All these services are turned off by default. Kerberos 4 is always supported by the KDC, but the Kerberos 4 client support also depends on Kerberos 4 support having been included at compile-time, using `--with-krb4=dir'. 4.6.1 524 --------- 524 is a service that allows the KDC to convert Kerberos 5 tickets to Kerberos 4 tickets for backward compatibility. See also Using 2b tokens with AFS in *Note AFS::. 524 can be turned on by adding this to the configuration file [kdc] enable-524 = yes 4.6.2 Kerberos 4 ---------------- Kerberos 4 is the predecessor to to Kerberos 5. It only supports single DES. You should only enable Kerberos 4 support if you have needs for compatibility with an installed base of Kerberos 4 clients/servers. Kerberos 4 can be turned on by adding this to the configuration file [kdc] enable-kerberos4 = yes 4.6.3 kaserver -------------- Kaserver is a Kerberos 4 that is used in AFS. The protocol has some extra features over plain Kerberos 4, but like Kerberos 4, only uses single DES. You should only enable Kaserver support if you have needs for compatibility with an installed base of AFS machines. Kaserver can be turned on by adding this to the configuration file [kdc] enable-kaserver = yes  File: heimdal.info, Node: Remote administration, Next: Password changing, Prev: Serving Kerberos 4/524/kaserver, Up: Setting up a realm 4.7 Remote administration ========================= The administration server, `kadmind', can be started by `inetd' (which isn't recommended) or run as a normal daemon. If you want to start it from `inetd' you should add a line similar to the one below to your `/etc/inetd.conf'. kerberos-adm stream tcp nowait root /usr/heimdal/libexec/kadmind kadmind You might need to add `kerberos-adm' to your `/etc/services' as `749/tcp'. Access to the administration server is controlled by an ACL file, (default `/var/heimdal/kadmind.acl'.) The file has the following syntax: principal [priv1,priv2,...] [glob-pattern] The matching is from top to bottom for matching principals (and if given, glob-pattern). When there is a match, the access rights of that line are applied. The privileges you can assign to a principal are: `add', `change-password' (or `cpw' for short), `delete', `get', `list', and `modify', or the special privilege `all'. All of these roughly correspond to the different commands in `kadmin'. If a GLOB-PATTERN is given on a line, it restricts the access rights for the principal to only apply for subjects that match the pattern. The patterns are of the same type as those used in shell globbing, see fnmatch(3). In the example below `lha/admin' can change every principal in the database. `jimmy/admin' can only modify principals that belong to the realm `E.KTH.SE'. `mille/admin' is working at the help desk, so he should only be able to change the passwords for single component principals (ordinary users). He will not be able to change any `/admin' principal. lha/admin@E.KTH.SE all jimmy/admin@E.KTH.SE all *@E.KTH.SE jimmy/admin@E.KTH.SE all */*@E.KTH.SE mille/admin@E.KTH.SE change-password *@E.KTH.SE  File: heimdal.info, Node: Password changing, Next: Testing clients and servers, Prev: Remote administration, Up: Setting up a realm 4.8 Password changing ===================== To allow users to change their passwords, you should run `kpasswdd'. It is not run from `inetd'. You might need to add `kpasswd' to your `/etc/services' as `464/udp'. If your realm is not setup to use DNS, you might also need to add a `kpasswd_server' entry to the realm configuration in `/etc/krb5.conf' on client machines: [realms] MY.REALM = { kdc = my.kdc my.slave.kdc kpasswd_server = my.kdc } 4.8.1 Password quality assurance -------------------------------- It is important that users have good passwords, both to make it harder to guess them and to avoid off-line attacks (although pre-authentication provides some defence against off-line attacks). To ensure that the users choose good passwords, you can enable password quality controls in `kpasswdd' and `kadmind'. The controls themselves are done in a shared library or an external program that is used by `kpasswdd'. To configure in these controls, add lines similar to the following to your `/etc/krb5.conf': [password_quality] policies = external-check builtin:minimum-length modulename:policyname external_program = /bin/false policy_libraries = LIBRARY1.SO LIBRARY2.SO In `[password_quality]policies' the module name is optional if the policy name is unique in all modules (members of `policy_libraries'). All built-in policies can be qualified with a module name of `builtin' to unambiguously specify the built-in policy and not a policy by the same name from a loaded module. The built-in policies are * external-check Executes the program specified by `[password_quality]external_program'. A number of key/value pairs are passed as input to the program, one per line, ending with the string `end'. The key/value lines are of the form principal: PRINCIPAL new-password: PASSWORD where PASSWORD is the password to check for the previous PRINCIPAL. If the external application approves the password, it should return `APPROVED' on standard out and exit with exit code 0. If it doesn't approve the password, an one line error message explaining the problem should be returned on standard error and the application should exit with exit code 0. In case of a fatal error, the application should, if possible, print an error message on standard error and exit with a non-zero error code. * minimum-length The minimum length password quality check reads the configuration file stanza `[password_quality]min_length' and requires the password to be at least this length. * character-class The character-class password quality check reads the configuration file stanza `[password_quality]min_classes'. The policy requires the password to have characters from at least that many character classes. Default value if not given is 3. The four different characters classes are, uppercase, lowercase, number, special characters. If you want to write your own shared object to check password policies, see the manual page `kadm5_pwcheck(3)'. Code for a password quality checking function that uses the cracklib library can be found in `lib/kadm5/sample_password_check.c' in the source code distribution. It requires that the cracklib library be built with the patch available at `ftp://ftp.pdc.kth.se/pub/krb/src/cracklib.patch'. A sample policy external program is included in `lib/kadm5/check-cracklib.pl'. If no password quality checking function is configured, the only check performed is that the password is at least six characters long. To check the password policy settings, use the command `verify-password-quality' in `kadmin' program. The password verification is only performed locally, on the client. It may be convenient to set the environment variable `KRB5_CONFIG' to point to a test version of `krb5.conf' while you're testing the `[password_quality]' stanza that way.  File: heimdal.info, Node: Testing clients and servers, Next: Slave Servers, Prev: Password changing, Up: Setting up a realm 4.9 Testing clients and servers =============================== Now you should be able to run all the clients and servers. Refer to the appropriate man pages for information on how to use them.  File: heimdal.info, Node: Slave Servers, Next: Incremental propagation, Prev: Testing clients and servers, Up: Setting up a realm 4.10 Slave servers, Incremental propagation, Testing clients and servers, Setting up a realm ============================================================================================ It is desirable to have at least one backup (slave) server in case the master server fails. It is possible to have any number of such slave servers but more than three usually doesn't buy much more redundancy. All Kerberos servers for a realm must have the same database so that they present the same service to the users. The `hprop' program, running on the master, will propagate the database to the slaves, running `hpropd' processes. Every slave needs a database directory, the master key (if it was used for the database) and a keytab with the principal `hprop/HOSTNAME'. Add the principal with the `ktutil' command and start `hpropd', as follows: slave# ktutil get -p foo/admin hprop/`hostname` slave# mkdir /var/heimdal slave# hpropd The master will use the principal `kadmin/hprop' to authenticate to the slaves. This principal should be added when running `kadmin -l init' but if you do not have it in your database for whatever reason, please add it with `kadmin -l add'. Then run `hprop' on the master: master# hprop slave This was just an hands-on example to make sure that everything was working properly. Doing it manually is of course the wrong way, and to automate this you will want to start `hpropd' from `inetd' on the slave(s) and regularly run `hprop' on the master to regularly propagate the database. Starting the propagation once an hour from `cron' is probably a good idea.  File: heimdal.info, Node: Incremental propagation, Next: Encryption types and salting, Prev: Slave Servers, Up: Setting up a realm 4.11 Incremental propagation ============================ There is also a newer mechanism for doing incremental propagation in Heimdal. Instead of sending the whole database regularly, it sends the changes as they happen on the master to the slaves. The master keeps track of all the changes by assigning a version number to every change to the database. The slaves know which was the latest version they saw and in this way it can be determined if they are in sync or not. A log of all the changes is kept on the master, and when a slave is at an older version than the oldest one in the log, the whole database has to be sent. Protocol-wise, all the slaves connect to the master and as a greeting tell it the latest version that they have (`IHAVE' message). The master then responds by sending all the changes between that version and the current version at the master (a series of `FORYOU' messages) or the whole database in a `TELLYOUEVERYTHING' message. There is also a keep-alive protocol that makes sure all slaves are up and running. In addition on listening on the network to get connection from new slaves, the ipropd-master also listens on a status unix socket. kadmind and kpasswdd both open that socket when a transation is done and written a notification to the socket. That cause ipropd-master to check for new version in the log file. As a fallback in case a notification is lost by the unix socket, the log file is checked after 30 seconds of no event. 4.11.1 Configuring incremental propagation ------------------------------------------ The program that runs on the master is `ipropd-master' and all clients run `ipropd-slave'. Create the file `/var/heimdal/slaves' on the master containing all the slaves that the database should be propagated to. Each line contains the full name of the principal (for example `iprop/hemligare.foo.se@FOO.SE'). You should already have `iprop/tcp' defined as 2121, in your `/etc/services'. Otherwise, or if you need to use a different port for some peculiar reason, you can use the `--port' option. This is useful when you have multiple realms to distribute from one server. Then you need to create those principals that you added in the configuration file. Create one `iprop/hostname' for the master and for every slave. master# /usr/heimdal/sbin/ktutil get iprop/`hostname` slave# /usr/heimdal/sbin/ktutil get iprop/`hostname` The next step is to start the `ipropd-master' process on the master server. The `ipropd-master' listens on the UNIX domain socket `/var/heimdal/signal' to know when changes have been made to the database so they can be propagated to the slaves. There is also a safety feature of testing the version number regularly (every 30 seconds) to see if it has been modified by some means that do not raise this signal. Then, start `ipropd-slave' on all the slaves: master# /usr/heimdal/libexec/ipropd-master & slave# /usr/heimdal/libexec/ipropd-slave master & To manage the iprop log file you should use the `iprop-log' command. With it you can dump, truncate and replay the logfile.  File: heimdal.info, Node: Encryption types and salting, Next: Credential cache server - KCM, Prev: Incremental propagation, Up: Setting up a realm 4.12 Encryption types and salting ================================= The encryption types that the KDC is going to assign by default is possible to change. Since the keys used for user authentication is salted the encryption types are described together with the salt strings. Salting is used to make it harder to pre-calculate all possible keys. Using a salt increases the search space to make it almost impossible to pre-calculate all keys. Salting is the process of mixing a public string (the salt) with the password, then sending it through an encryption type specific string-to-key function that will output the fixed size encryption key. In Kerberos 5 the salt is determined by the encryption type, except in some special cases. In `des' there is the Kerberos 4 salt (none at all) or the afs-salt (using the cell (realm in AFS lingo)). In `arcfour' (the encryption type that Microsoft Windows 2000 uses) there is no salt. This is to be compatible with NTLM keys in Windows NT 4. `[kadmin]default_keys' in `krb5.conf' controls what salting to use. The syntax of `[kadmin]default_keys' is `[etype:]salt-type[:salt-string]'. `etype' is the encryption type (des-cbc-crc, arcfour-hmac-md5, aes256-cts-hmac-sha1-96), `salt-type' is the type of salt (pw-salt or afs3-salt), and the salt-string is the string that will be used as salt (remember that if the salt is appended/prepended, the empty salt "" is the same thing as no salt at all). Common types of salting include * `v4' (or `des:pw-salt:') The Kerberos 4 salting is using no salt at all. Reason there is colon at the end of the salt string is that it makes the salt the empty string (same as no salt). * `v5' (or `pw-salt') `pw-salt' uses the default salt for each encryption type is specified for. If the encryption type `etype' isn't given, all default encryption will be used. * `afs3-salt' `afs3-salt' is the salt that is used with Transarc kaserver. It's the cell name appended to the password.  File: heimdal.info, Node: Credential cache server - KCM, Next: Cross realm, Prev: Encryption types and salting, Up: Setting up a realm 4.13 Credential cache server - KCM ================================== When KCM running is easy for users to switch between different kerberos principals using `kswitch' or built in support in application, like OpenSSH's GSSAPIClientIdentity. Other advantages are that there is the long term credentials are not written to disk and on reboot the credential is removed when kcm process stopps running. Configure the system startup script to start the kcm process, `/usr/heimdal/libexec/kcm' and then configure the system to use kcm in `krb5.conf'. [libdefaults] default_cc_type = KCM Now when you run `kinit' it doesn't overwrite your existing credentials but rather just add them to the set of credentials. `klist -l' lists the credentials and the star marks the default credential. $ kinit lha@KTH.SE lha@KTH.SE's Password: $ klist -l Name Cache name Expires lha@KTH.SE 0 Nov 22 23:09:40 * lha@SU.SE Initial default ccache Nov 22 14:14:24 When switching between credentials you can use `kswitch'. $ kswitch -i Principal 1 lha@KTH.SE 2 lha@SU.SE Select number: 2 After switching, a new set of credentials are used as default. $ klist -l Name Cache name Expires lha@SU.SE Initial default ccache Nov 22 14:14:24 * lha@KTH.SE 0 Nov 22 23:09:40 Som applications, like openssh with Simon Wilkinsons patch applied, support specifiying that credential to use. The example below will login to the host computer.kth.se using lha@KTH.SE (not the current default credential). $ ssh \ -o GSSAPIAuthentication=yes \ -o GSSAPIKeyExchange=yes \ -o GSSAPIClientIdentity=lha@KTH.SE \ computer.kth.se  File: heimdal.info, Node: Cross realm, Next: Transit policy, Prev: Credential cache server - KCM, Up: Setting up a realm 4.14 Cross realm ================ Suppose you reside in the realm `MY.REALM', how do you authenticate to a server in `OTHER.REALM'? Having valid tickets in `MY.REALM' allows you to communicate with Kerberised services in that realm. However, the computer in the other realm does not have a secret key shared with the Kerberos server in your realm. It is possible to share keys between two realms that trust each other. When a client program, such as `telnet' or `ssh', finds that the other computer is in a different realm, it will try to get a ticket granting ticket for that other realm, but from the local Kerberos server. With that ticket granting ticket, it will then obtain service tickets from the Kerberos server in the other realm. For a two way trust between `MY.REALM' and `OTHER.REALM' add the following principals to each realm. The principals should be `krbtgt/OTHER.REALM@MY.REALM' and `krbtgt/MY.REALM@OTHER.REALM' in `MY.REALM', and `krbtgt/MY.REALM@OTHER.REALM' and `krbtgt/OTHER.REALM@MY.REALM'in `OTHER.REALM'. In Kerberos 5 the trust can be configured to be one way. So that users from `MY.REALM' can authenticate to services in `OTHER.REALM', but not the opposite. In the example above, the `krbtgt/MY.REALM@OTHER.REALM' then should be removed. The two principals must have the same key, key version number, and the same set of encryption types. Remember to transfer the two keys in a safe manner. vr$ klist Credentials cache: FILE:/tmp/krb5cc_913.console Principal: lha@E.KTH.SE Issued Expires Principal May 3 13:55:52 May 3 23:55:54 krbtgt/E.KTH.SE@E.KTH.SE vr$ telnet -l lha hummel.it.su.se Trying 2001:6b0:5:1095:250:fcff:fe24:dbf... Connected to hummel.it.su.se. Escape character is '^]'. Waiting for encryption to be negotiated... [ Trying mutual KERBEROS5 (host/hummel.it.su.se@SU.SE)... ] [ Kerberos V5 accepts you as ``lha@E.KTH.SE'' ] Encryption negotiated. Last login: Sat May 3 14:11:47 from vr.l.nxs.se hummel$ exit vr$ klist Credentials cache: FILE:/tmp/krb5cc_913.console Principal: lha@E.KTH.SE Issued Expires Principal May 3 13:55:52 May 3 23:55:54 krbtgt/E.KTH.SE@E.KTH.SE May 3 13:55:56 May 3 23:55:54 krbtgt/SU.SE@E.KTH.SE May 3 14:10:54 May 3 23:55:54 host/hummel.it.su.se@SU.SE  File: heimdal.info, Node: Transit policy, Next: Setting up DNS, Prev: Cross realm, Up: Setting up a realm 4.15 Transit policy =================== Under some circumstances, you may not wish to set up direct cross-realm trust with every realm to which you wish to authenticate or from which you wish to accept authentications. Kerberos supports multi-hop cross-realm trust where a client principal in realm A authenticates to a service in realm C through a realm B with which both A and C have cross-realm trust relationships. In this situation, A and C need not set up cross-realm principals between each other. If you want to use cross-realm authentication through an intermediate realm, it must be explicitly allowed by either the KDCs for the realm to which the client is authenticating (in this case, realm C), or the server receiving the request. This is done in `krb5.conf' in the `[capaths]' section. In addition, the client in realm A need to be configured to know how to reach realm C via realm B. This can be done either on the client or via KDC configuration in the KDC for realm A. 4.15.1 Allowing cross-realm transits ------------------------------------ When the ticket transits through a realm to another realm, the destination realm adds its peer to the "transited-realms" field in the ticket. The field is unordered, since there is no way to know if know if one of the transited-realms changed the order of the list. For the authentication to be accepted by the final destination realm, all of the transited realms must be listed as trusted in the `[capaths]' configuration, either in the KDC for the destination realm or on the server receiving the authentication. The syntax for `[capaths]' section is: [capaths] CLIENT-REALM = { SERVER-REALM = PERMITTED-CROSS-REALMS ... } In the following example, the realm `STACKEN.KTH.SE' only has direct cross-realm set up with `KTH.SE'. `KTH.SE' has direct cross-realm set up with `STACKEN.KTH.SE' and `SU.SE'. `DSV.SU.SE' only has direct cross-realm set up with `SU.SE'. The goal is to allow principals in the `DSV.SU.SE' or `SU.SE' realms to authenticate to services in `STACKEN.KTH.SE'. This is done with the following `[capaths]' entry on either the server accepting authentication or on the KDC for `STACKEN.KTH.SE'. [capaths] SU.SE = { STACKEN.KTH.SE = KTH.SE } DSV.SU.SE = { STACKEN.KTH.SE = SU.SE KTH.SE } The first entry allows cross-realm authentication from clients in `SU.SE' transiting through `KTH.SE' to `STACKEN.KTH.SE'. The second entry allows cross-realm authentication from clients in `DSV.SU.SE' transiting through both `SU.SE' and `KTH.SE' to `STACKEN.KTH.SE'. Be careful of which realm goes where; it's easy to put realms in the wrong place. The block is tagged with the client realm (the realm of the principal authenticating), and the realm before the equal sign is the final destination realm: the realm to which the client is authenticating. After the equal sign go all the realms that the client transits through. The order of the `PERMITTED-CROSS-REALMS' is not important when doing transit cross realm verification. 4.15.2 Configuring client cross-realm transits ---------------------------------------------- The `[capaths]' section is also used for another purpose: to tell clients which realm to transit through to reach a realm with which their local realm does not have cross-realm trust. This can be done by either putting a `[capaths]' entry in the configuration of the client or by putting the entry in the configuration of the KDC for the client's local realm. In the latter case, the KDC will then hand back a referral to the client when the client requests a cross-realm ticket to the destination realm, telling the client to try to go through an intermediate realm. For client configuration, the order of `PERMITTED-CROSS-REALMS' is significant, since only the first realm in this section (after the equal sign) is used by the client. For example, again consider the `[capaths]' entry above for the case of a client in the `SU.SE' realm, and assume that the client or the `SU.SE' KDC has that `[capaths]' entry. If the client attempts to authenticate to a service in the `STACKEN.KTH.SE' realm, that entry says to first authenticate cross-realm to the `KTH.SE' realm (the first realm listed in the `PERMITTED-CROSS-REALMS' section), and then from there to `STACKEN.KTH.SE'. Each entry in `[capaths]' can only give the next hop, since only the first realm in `PERMITTED-CROSS-REALMS' is used. If, for instance, a client in `DSV.SU.SE' had a `[capaths]' configuration as above but without the first block for `SU.SE', they would not be able to reach `STACKEN.KTH.SE'. They would get as far as `SU.SE' based on the `DSV.SU.SE' entry in `[capaths]' and then attempt to go directly from there to `STACKEN.KTH.SE' and get stuck (unless, of course, the `SU.SE' KDC had the additional entry required to tell the client to go through `KTH.SE'). 4.15.3 Active Directory forest example -------------------------------------- One common place where a `[capaths]' configuration is desirable is with Windows Active Directory forests. One common Active Directory configuration is to have one top-level Active Directory realm but then divide systems, services, and users into child realms (perhaps based on organizational unit). One generally establishes cross-realm trust only with the top-level realm, and then uses transit policy to permit authentications to and from the child realms. For example, suppose an organization has a Heimdal realm `EXAMPLE.COM', a Windows Active Directory realm `WIN.EXAMPLE.COM', and then child Active Directory realms `ENGR.WIN.EXAMPLE.COM' and `SALES.WIN.EXAMPLE.COM'. The goal is to allow users in any of these realms to authenticate to services in any of these realms. The `EXAMPLE.COM' KDC (and possibly client) configuration should therefore contain a `[capaths]' section as follows: [capaths] ENGR.WIN.EXAMPLE.COM = { EXAMPLE.COM = WIN.EXAMPLE.COM } SALES.WIN.EXAMPLE.COM = { EXAMPLE.COM = WIN.EXAMPLE.COM } EXAMPLE.COM = { ENGR.WIN.EXAMPLE.COM = WIN.EXAMPLE.COM SALES.WIN.EXAMPLE.COM = WIN.EXAMPLE.COM } The first two blocks allow clients in the `ENGR.WIN.EXAMPLE.COM' and `SALES.WIN.EXAMPLE.COM' realms to authenticate to services in the `EXAMPLE.COM' realm. The third block tells the client (or tells the KDC to tell the client via referrals) to transit through `WIN.EXAMPLE.COM' to reach these realms. Both sides of the configuration are needed for bi-directional transited cross-realm authentication.  File: heimdal.info, Node: Setting up DNS, Next: Using LDAP to store the database, Prev: Transit policy, Up: Setting up a realm 4.16 Setting up DNS =================== 4.16.1 Using DNS to find KDC ---------------------------- If there is information about where to find the KDC or kadmind for a realm in the `krb5.conf' for a realm, that information will be preferred, and DNS will not be queried. Heimdal will try to use DNS to find the KDCs for a realm. First it will try to find a `SRV' resource record (RR) for the realm. If no SRV RRs are found, it will fall back to looking for an `A' RR for a machine named kerberos.REALM, and then kerberos-1.REALM, etc Adding this information to DNS minimises the client configuration (in the common case, resulting in no configuration needed) and allows the system administrator to change the number of KDCs and on what machines they are running without caring about clients. The downside of using DNS is that the client might be fooled to use the wrong server if someone fakes DNS replies/data, but storing the IP addresses of the KDC on all the clients makes it very hard to change the infrastructure. An example of the configuration for the realm `EXAMPLE.COM': $ORIGIN example.com. _kerberos._tcp SRV 10 1 88 kerberos.example.com. _kerberos._udp SRV 10 1 88 kerberos.example.com. _kerberos._tcp SRV 10 1 88 kerberos-1.example.com. _kerberos._udp SRV 10 1 88 kerberos-1.example.com. _kpasswd._udp SRV 10 1 464 kerberos.example.com. _kerberos-adm._tcp SRV 10 1 749 kerberos.example.com. More information about DNS SRV resource records can be found in RFC-2782 (A DNS RR for specifying the location of services (DNS SRV)). 4.16.2 Using DNS to map hostname to Kerberos realm -------------------------------------------------- Heimdal also supports a way to lookup a realm from a hostname. This to minimise configuration needed on clients. Using this has the drawback that clients can be redirected by an attacker to realms within the same cross realm trust and made to believe they are talking to the right server (since Kerberos authentication will succeed). An example configuration that informs clients that for the realms it.example.com and srv.example.com, they should use the realm EXAMPLE.COM: $ORIGIN example.com. _kerberos.it TXT "EXAMPLE.COM" _kerberos.srv TXT "EXAMPLE.COM"  File: heimdal.info, Node: Using LDAP to store the database, Next: Providing Kerberos credentials to servers and programs, Prev: Setting up DNS, Up: Setting up a realm 4.17 Using LDAP to store the database ===================================== This document describes how to install the LDAP backend for Heimdal. Note that before attempting to configure such an installation, you should be aware of the implications of storing private information (such as users' keys) in a directory service primarily designed for public information. Nonetheless, with a suitable authorisation policy, it is possible to set this up in a secure fashion. A knowledge of LDAP, Kerberos, and C is necessary to install this backend. The HDB schema was devised by Leif Johansson. This assumes, OpenLDAP 2.3 or later. Requirements: * A current release of Heimdal, configured with `--with-openldap=/usr/local' (adjust according to where you have installed OpenLDAP). You can verify that you manage to configure LDAP support by running `kdc --builtin-hdb', and checking that `ldap:' is one entry in the list. Its also possible to configure the ldap backend as a shared module, see option -hdb-openldap-module to configure. * Configure OpenLDAP with `--enable-local' to enable the local transport. * Add the hdb schema to the LDAP server, it's included in the source-tree in `lib/hdb/hdb.schema'. Example from slapd.conf: include /usr/local/etc/openldap/schema/hdb.schema * Configure the LDAP server ACLs to accept writes from clients over the local transport. For example: access to * by dn.exact="uid=heimdal,dc=services,dc=example,dc=com" write ... authz-regexp "gidNumber=.*\\\+uidNumber=0,cn=peercred,cn=external,cn=auth'' "uid=heimdal,dc=services,dc=example,dc=com" The sasl-regexp is for mapping between the SASL/EXTERNAL and a user in a tree. The user that the key is mapped to should be have a krb5Principal aux object with krb5PrincipalName set so that the "creator" and "modifier" is right in `kadmin'. Another option is to create an admins group and add the dn to that group. Since Heimdal talks to the LDAP server over a UNIX domain socket, and uses external sasl authentication, it's not possible to require security layer quality (ssf in cyrus-sasl lingo). So that requirement has to be turned off in OpenLDAP `slapd' configuration file `slapd.conf'. sasl-secprops minssf=0 * Start `slapd' with the local listener (as well as the default TCP/IP listener on port 389) as follows: slapd -h "ldapi:/// ldap:///" Note: These is a bug in `slapd' where it appears to corrupt the krb5Key binary attribute on shutdown. This may be related to our use of the V3 schema definition syntax instead of the old UMich-style, V2 syntax. * You should specify the distinguished name under which your principals will be stored in `krb5.conf'. Also you need to enter the path to the kadmin acl file: [kdc] database = { dbname = ldap:ou=KerberosPrincipals,dc=example,dc=com hdb-ldap-structural-object = inetOrgPerson acl_file = /path/to/kadmind.acl mkey_file = /path/to/mkey } `mkey_file' can be excluded if you feel that you trust your ldap directory to have the raw keys inside it. The hdb-ldap-structural-object is not necessary if you do not need Samba comatibility. * Once you have built Heimdal and started the LDAP server, run kadmin (as usual) to initialise the database. Note that the instructions for stashing a master key are as per any Heimdal installation. kdc# kadmin -l kadmin> init EXAMPLE.COM Realm max ticket life [unlimited]: Realm max renewable ticket life [unlimited]: kadmin> add lukeh Max ticket life [1 day]: Max renewable life [1 week]: Principal expiration time [never]: Password expiration time [never]: Attributes []: lukeh@EXAMPLE.COM's Password: Verifying password - lukeh@EXAMPLE.COM's Password: kadmin> exit Verify that the principal database has indeed been stored in the directory with the following command: kdc# ldapsearch -L -h localhost -D cn=manager \ -w secret -b ou=KerberosPrincipals,dc=example,dc=com \ 'objectclass=krb5KDCEntry' * Now consider adding indexes to the database to speed up the access, at least theses should be added to slapd.conf. index objectClass eq index cn eq,sub,pres index uid eq,sub,pres index displayName eq,sub,pres index krb5PrincipalName eq 4.17.1 smbk5pwd overlay ----------------------- The smbk5pwd overlay, updates the krb5Key and krb5KeyVersionNumber appropriately when it receives an LDAP Password change Extended Operation: `http://www.openldap.org/devel/cvsweb.cgi/contrib/slapd-modules/smbk5pwd/README?hideattic=1&sortbydate=0' 4.17.2 Troubleshooting guide ---------------------------- `https://sec.miljovern.no/bin/view/Info/TroubleshootingGuide' 4.17.3 Using Samba LDAP password database ----------------------------------------- The Samba domain and the Kerberos realm can have different names since arcfour's string to key functions principal/realm independent. So now will be your first and only chance name your Kerberos realm without needing to deal with old configuration files. First, you should set up Samba and get that working with LDAP backend. Now you can proceed as in *Note Using LDAP to store the database::. Heimdal will pick up the Samba LDAP entries if they are in the same search space as the Kerberos entries.  File: heimdal.info, Node: Providing Kerberos credentials to servers and programs, Next: Setting up PK-INIT, Prev: Using LDAP to store the database, Up: Setting up a realm 4.18 Providing Kerberos credentials to servers and programs =========================================================== Some services require Kerberos credentials when they start to make connections to other services or need to use them when they have started. The easiest way to get tickets for a service is to store the key in a keytab. Both ktutil get and kadmin ext can be used to get a keytab. ktutil get is better in that way it changes the key/password for the user. This is also the problem with ktutil. If ktutil is used for the same service principal on several hosts, they keytab will only be useful on the last host. In that case, run the extract command on one host and then securely copy the keytab around to all other hosts that need it. host# ktutil -k /etc/krb5-service.keytab \ get -p lha/admin@EXAMPLE.ORG service-principal@EXAMPLE.ORG lha/admin@EXAMPLE.ORG's Password: To get a Kerberos credential file for the service, use kinit in the `--keytab' mode. This will not ask for a password but instead fetch the key from the keytab. service@host$ kinit --cache=/var/run/service_krb5_cache \ --keytab=/etc/krb5-service.keytab \ service-principal@EXAMPLE.ORG Long running services might need credentials longer then the expiration time of the tickets. kinit can run in a mode that refreshes the tickets before they expire. This is useful for services that write into AFS and other distributed file systems using Kerberos. To run the long running script, just append the program and arguments (if any) after the principal. kinit will stop refreshing credentials and remove the credentials when the script-to-start-service exits. service@host$ kinit --cache=/var/run/service_krb5_cache \ --keytab=/etc/krb5-service.keytab \ service-principal@EXAMPLE.ORG \ script-to-start-service argument1 argument2  File: heimdal.info, Node: Setting up PK-INIT, Next: Debugging Kerberos problems, Prev: Providing Kerberos credentials to servers and programs, Up: Setting up a realm 4.19 Setting up PK-INIT ======================= PK-INIT leverages an existing PKI (public key infrastructure), using certificates to get the initial ticket (usually the krbtgt ticket-granting ticket). To use PK-INIT you must first have a PKI. If you don't have one, it is time to create it. You should first read the whole chapter of the document to see the requirements imposed on the CA software. A mapping between the PKI certificate and what principals that certificate is allowed to use must exist. There are several ways to do this. The administrator can use a configuration file, store the principal in the SubjectAltName extension of the certificate, or store the mapping in the principals entry in the kerberos database. 4.20 Certificates ================= This section documents the requirements on the KDC and client certificates and the format used in the id-pkinit-san OtherName extention. 4.20.1 KDC certificate ---------------------- The certificate for the KDC has serveral requirements. First, the certificate should have an Extended Key Usage (EKU) id-pkkdcekuoid (1.3.6.1.5.2.3.5) set. Second, there must be a subjectAltName otherName using OID id-pkinit-san (1.3.6.1.5.2.2) in the type field and a DER encoded KRB5PrincipalName that matches the name of the TGS of the target realm. Also, if the certificate has a nameConstraints extention with a Generalname with dNSName or iPAdress, it must match the hostname or adress of the KDC. The client is not required by the standard to check the server certificate for this information if the client has external information confirming which certificate the KDC is supposed to be using. However, adding this information to the KDC certificate removes the need to specially configure the client to recognize the KDC certificate. Remember that if the client would accept any certificate as the KDC's certificate, the client could be fooled into trusting something that isn't a KDC and thus expose the user to giving away information (like a password or other private information) that it is supposed to keep secret. 4.20.2 Client certificate ------------------------- The client certificate may need to have a EKU id-pkekuoid (1.3.6.1.5.2.3.4) set depending on the certifiate on the KDC. It possible to store the principal (if allowed by the KDC) in the certificate and thus delegate responsibility to do the mapping between certificates and principals to the CA. This behavior is controlled by KDC configuration option: [kdc] pkinit_principal_in_certificate = yes 4.20.2.1 Using KRB5PrincipalName in id-pkinit-san ................................................. The OtherName extention in the GeneralName is used to do the mapping between certificate and principal. For the KDC certificate, this stores the krbtgt principal name for that KDC. For the client certificate, this stores the principal for which that certificate is allowed to get tickets. The principal is stored in a SubjectAltName in the certificate using OtherName. The OID in the type is id-pkinit-san. id-pkinit-san OBJECT IDENTIFIER ::= { iso (1) org (3) dod (6) internet (1) security (5) kerberosv5 (2) 2 } The data part of the OtherName is filled with the following DER encoded ASN.1 structure: KRB5PrincipalName ::= SEQUENCE { realm [0] Realm, principalName [1] PrincipalName } where Realm and PrincipalName is defined by the Kerberos ASN.1 specification. 4.21 Naming certificate using hx509 =================================== hx509 is the X.509 software used in Heimdal to handle certificates. hx509 supports several different syntaxes for specifying certificate files or formats. Several formats may be used: PEM, certificates embedded in PKCS#12 files, certificates embedded in PKCS#11 devices, and raw DER encoded certificates. Those formats may be specified as follows: DIR: DIR specifies a directory which contains certificates in the DER or PEM format. The main feature of DIR is that the directory is read on demand when iterating over certificates. This allows applications, in some situations, to avoid having to store all certificates in memory. It's very useful for tests that iterate over large numbers of certificates. The syntax is: DIR:/path/to/der/files FILE: FILE: specifies a file that contains a certificate or private key. The file can be either a PEM (openssl) file or a raw DER encoded certificate. If it's a PEM file, it can contain several keys and certificates and the code will try to match the private key and certificate together. Multiple files may be specified, separated by commas. It's useful to have one PEM file that contains all the trust anchors. The syntax is: FILE:certificate.pem,private-key.key,other-cert.pem,.... PKCS11: PKCS11: is used to handle smartcards via PKCS#11 drivers, such as soft-token, opensc, or muscle. The argument specifies a shared object that implements the PKCS#11 API. The default is to use all slots on the device/token. The syntax is: PKCS11:shared-object.so PKCS12: PKCS12: is used to handle PKCS#12 files. PKCS#12 files commonly have the extension pfx or p12. The syntax is: PKCS12:/path/to/file.pfx 4.22 Configure the Kerberos software ==================================== First configure the client's trust anchors and what parameters to verify. See the subsections below for how to do that. Then, you can use kinit to get yourself tickets. For example: $ kinit -C FILE:$HOME/.certs/lha.crt,$HOME/.certs/lha.key lha@EXAMPLE.ORG Enter your private key passphrase: : lha@nutcracker ; klist Credentials cache: FILE:/tmp/krb5cc_19100a Principal: lha@EXAMPLE.ORG Issued Expires Principal Apr 20 02:08:08 Apr 20 12:08:08 krbtgt/EXAMPLE.ORG@EXAMPLE.ORG Using PKCS#11 it can look like this instead: $ kinit -C PKCS11:/usr/heimdal/lib/hx509.so lha@EXAMPLE.ORG PIN code for SoftToken (slot): $ klist Credentials cache: API:4 Principal: lha@EXAMPLE.ORG Issued Expires Principal Mar 26 23:40:10 Mar 27 09:40:10 krbtgt/EXAMPLE.ORG@EXAMPLE.ORG TODO: Write about the KDC. 4.23 Configure the client ========================= [appdefaults] pkinit_anchors = FILE:/path/to/trust-anchors.pem [realms] EXAMPLE.COM = { pkinit_require_eku = true pkinit_require_krbtgt_otherName = true pkinit_win2k = no pkinit_win2k_require_binding = yes } 4.24 Configure the KDC ====================== [kdc] enable-pkinit = yes pkinit_identity = FILE:/secure/kdc.crt,/secure/kdc.key pkinit_anchors = FILE:/path/to/trust-anchors.pem pkinit_pool = PKCS12:/path/to/useful-intermediate-certs.pfx pkinit_pool = FILE:/path/to/other-useful-intermediate-certs.pem pkinit_allow_proxy_certificate = no pkinit_win2k_require_binding = yes pkinit_principal_in_certificate = no 4.24.1 Using pki-mapping file ----------------------------- Note that the file name is space sensitive. # cat /var/heimdal/pki-mapping # comments starts with # lha@EXAMPLE.ORG:C=SE,O=Stockholm universitet,CN=Love,UID=lha lha@EXAMPLE.ORG:CN=Love,UID=lha 4.24.2 Using the Kerberos database ---------------------------------- 4.25 Use hxtool to create certificates ====================================== 4.25.1 Generate certificates ---------------------------- First, you need to generate a CA certificate. This example creates a CA certificate that will be valid for 10 years. You need to change -subject in the command below to something appropriate for your site. hxtool issue-certificate \ --self-signed \ --issue-ca \ --generate-key=rsa \ --subject="CN=CA,DC=test,DC=h5l,DC=se" \ --lifetime=10years \ --certificate="FILE:ca.pem" The KDC needs to have a certificate, so generate a certificate of the type "pkinit-kdc" and set the PK-INIT specifial SubjectAltName to the name of the krbtgt of the realm. You need to change -subject and -pk-init-principal in the command below to something appropriate for your site. hxtool issue-certificate \ --ca-certificate=FILE:ca.pem \ --generate-key=rsa \ --type="pkinit-kdc" \ --pk-init-principal="krbtgt/TEST.H5L.SE@TEST.H5L.SE" \ --subject="uid=kdc,DC=test,DC=h5l,DC=se" \ --certificate="FILE:kdc.pem" The users also needs to have certificates. For your first client, generate a certificate of type "pkinit-client". The client doesn't need to have the PK-INIT SubjectAltName set; you can have the Subject DN in the ACL file (pki-mapping) instead. You need to change -subject and -pk-init-principal in the command below to something appropriate for your site. You can omit -pk-init-principal if you're going to use the ACL file instead. hxtool issue-certificate \ --ca-certificate=FILE:ca.pem \ --generate-key=rsa \ --type="pkinit-client" \ --pk-init-principal="lha@TEST.H5L.SE" \ --subject="uid=lha,DC=test,DC=h5l,DC=se" \ --certificate="FILE:user.pem" 4.25.2 Validate the certificate ------------------------------- hxtool also contains a tool that will validate certificates according to rules from the PKIX document. These checks are not complete, but they provide a good test of whether you got all of the basic bits right in your certificates. hxtool validate FILE:user.pem 4.26 Use OpenSSL to create certificates ======================================= This section tries to give the CA owners hints how to create certificates using OpenSSL (or CA software based on OpenSSL). 4.26.1 Using OpenSSL to create certificates with krb5PrincipalName ------------------------------------------------------------------ To make OpenSSL create certificates with krb5PrincipalName, use an `openssl.cnf' as described below. To see a complete example of creating client and KDC certificates, see the test-data generation script `lib/hx509/data/gen-req.sh' in the source-tree. The certicates it creates are used to test the PK-INIT functionality in `tests/kdc/check-kdc.in'. To use this example you have to use OpenSSL 0.9.8a or later. [user_certificate] subjectAltName=otherName:1.3.6.1.5.2.2;SEQUENCE:princ_name [princ_name] realm = EXP:0, GeneralString:MY.REALM principal_name = EXP:1, SEQUENCE:principal_seq [principal_seq] name_type = EXP:0, INTEGER:1 name_string = EXP:1, SEQUENCE:principals [principals] princ1 = GeneralString:userid Command usage: openssl x509 -extensions user_certificate openssl ca -extensions user_certificate 4.27 Using PK-INIT with Windows =============================== 4.27.1 Client configration -------------------------- Clients using a Windows KDC with PK-INIT need configuration since windows uses pre-standard format and this can't be autodetected. The pkinit_win2k_require_binding option requires the reply for the KDC to be of the new, secure, type that binds the request to reply. Before, clients could fake the reply from the KDC. To use this option you have to apply a fix from Microsoft. [realms] MY.MS.REALM = { pkinit_win2k = yes pkinit_win2k_require_binding = no } 4.27.2 Certificates ------------------- The client certificates need to have the extended keyusage "Microsoft Smartcardlogin" (openssl has the OID shortname msSmartcardLogin). See Microsoft Knowledge Base Article - 281245 "Guidelines for Enabling Smart Card Logon with Third-Party Certification Authorities" for a more extensive description of how set setup an external CA so that it includes all the information required to make a Windows KDC happy. 4.27.3 Configure Windows 2000 CA -------------------------------- To enable Microsoft Smartcardlogin for certificates in your Windows 2000 CA, you want to look at Microsoft Knowledge Base Article - 313274 "HOW TO: Configure a Certification Authority to Issue Smart Card Certificates in Windows".  File: heimdal.info, Node: Debugging Kerberos problems, Prev: Setting up PK-INIT, Up: Setting up a realm 4.28 Debugging Kerberos problems ================================ To debug Kerberos client and server problems you can enable debug traceing by adding the following to `/etc/krb5,conf'. Note that the trace logging is sparse at the moment, but will continue to improve. [logging] libkrb5 = 0-/SYSLOG:  File: heimdal.info, Node: Applications, Next: Things in search for a better place, Prev: Setting up a realm, Up: Top 5 Applications ************** * Menu: * Authentication modules:: * AFS::  File: heimdal.info, Node: Authentication modules, Next: AFS, Prev: Applications, Up: Applications 5.1 Authentication modules ========================== The problem of having different authentication mechanisms has been recognised by several vendors, and several solutions have appeared. In most cases these solutions involve some kind of shared modules that are loaded at run-time. Modules for some of these systems can be found in `lib/auth'. Presently there are modules for Digital's SIA, and IRIX' `login' and `xdm' (in `lib/auth/afskauthlib'). * Menu: * Digital SIA:: * IRIX::  File: heimdal.info, Node: Digital SIA, Next: IRIX, Prev: Authentication modules, Up: Authentication modules 5.1.1 Digital SIA ----------------- How to install the SIA module depends on which OS version you're running. Tru64 5.0 has a new command, `siacfg', which makes this process quite simple. If you have this program, you should just be able to run: siacfg -a KRB5 /usr/athena/lib/libsia_krb5.so On older versions, or if you want to do it by hand, you have to do the following (not tested by us on Tru64 5.0): * Make sure `libsia_krb5.so' is available in `/usr/athena/lib'. If `/usr/athena' is not on local disk, you might want to put it in `/usr/shlib' or someplace else. If you do, you'll have to edit `krb5_matrix.conf' to reflect the new location (you will also have to do this if you installed in some other directory than `/usr/athena'). If you built with shared libraries, you will have to copy the shared `libkrb.so', `libdes.so', `libkadm.so', and `libkafs.so' to a place where the loader can find them (such as `/usr/shlib'). * Copy (your possibly edited) `krb5_matrix.conf' to `/etc/sia'. * Apply `security.patch' to `/sbin/init.d/security'. * Turn on KRB5 security by issuing `rcmgr set SECURITY KRB5' and `rcmgr set KRB5_MATRIX_CONF krb5_matrix.conf'. * Digital thinks you should reboot your machine, but that really shouldn't be necessary. It's usually sufficient just to run `/sbin/init.d/security start' (and restart any applications that use SIA, like `xdm'.) Users with local passwords (like `root') should be able to login safely. When using Digital's xdm the `KRB5CCNAME' environment variable isn't passed along as it should (since xdm zaps the environment). Instead you have to set `KRB5CCNAME' to the correct value in `/usr/lib/X11/xdm/Xsession'. Add a line similar to KRB5CCNAME=FILE:/tmp/krb5cc`id -u`_`ps -o ppid= -p $$`; export KRB5CCNAME If you use CDE, `dtlogin' allows you to specify which additional environment variables it should export. To add `KRB5CCNAME' to this list, edit `/usr/dt/config/Xconfig', and look for the definition of `exportList'. You want to add something like: Dtlogin.exportList: KRB5CCNAME Notes to users with Enhanced security ..................................... Digital's `ENHANCED' (C2) security, and Kerberos solve two different problems. C2 deals with local security, adds better control of who can do what, auditing, and similar things. Kerberos deals with network security. To make C2 security work with Kerberos you will have to do the following. * Replace all occurrences of `krb5_matrix.conf' with `krb5+c2_matrix.conf' in the directions above. * You must enable "vouching" in the `default' database. This will make the OSFC2 module trust other SIA modules, so you can login without giving your C2 password. To do this use `edauth' to edit the default entry `/usr/tcb/bin/edauth -dd default', and add a `d_accept_alternate_vouching' capability, if not already present. * For each user who does _not_ have a local C2 password, you should set the password expiration field to zero. You can do this for each user, or in the `default' table. To do this use `edauth' to set (or change) the `u_exp' capability to `u_exp#0'. * You also need to be aware that the shipped `login', `rcp', and `rshd', don't do any particular C2 magic (such as checking for various forms of disabled accounts), so if you rely on those features, you shouldn't use those programs. If you configure with `--enable-osfc2', these programs will, however, set the login UID. Still: use at your own risk. At present `su' does not accept the vouching flag, so it will not work as expected. Also, kerberised ftp will not work with C2 passwords. You can solve this by using both Digital's ftpd and our on different ports. *Remember*, if you do these changes you will get a system that most certainly does _not_ fulfil the requirements of a C2 system. If C2 is what you want, for instance if someone else is forcing you to use it, you're out of luck. If you use enhanced security because you want a system that is more secure than it would otherwise be, you probably got an even more secure system. Passwords will not be sent in the clear, for instance.  File: heimdal.info, Node: IRIX, Prev: Digital SIA, Up: Authentication modules 5.1.2 IRIX ---------- The IRIX support is a module that is compatible with Transarc's `afskauthlib.so'. It should work with all programs that use this library. This should include `login' and `xdm'. The interface is not very documented but it seems that you have to copy `libkafs.so', `libkrb.so', and `libdes.so' to `/usr/lib', or build your `afskauthlib.so' statically. The `afskauthlib.so' itself is able to reside in `/usr/vice/etc', `/usr/afsws/lib', or the current directory (wherever that is). IRIX 6.4 and newer seem to have all programs (including `xdm' and `login') in the N32 object format, whereas in older versions they were O32. For it to work, the `afskauthlib.so' library has to be in the same object format as the program that tries to load it. This might require that you have to configure and build for O32 in addition to the default N32. Apart from this it should "just work"; there are no configuration files. Note that recent Irix 6.5 versions (at least 6.5.22) have PAM, including a `pam_krb5.so' module. Not all relevant programs use PAM, though, e.g. `ssh'. In particular, for console graphical login you need to turn off `visuallogin' and turn on `xdm' with `chkconfig'.  File: heimdal.info, Node: AFS, Prev: Authentication modules, Up: Applications 5.2 AFS ======= AFS is a distributed filesystem that uses Kerberos for authentication. For more information about AFS see OpenAFS `http://www.openafs.org/' and Arla `http://www.stacken.kth.se/projekt/arla/'. 5.2.1 kafs and afslog --------------------- `afslog(1)' will obtains AFS tokens for a number of cells. What cells to get tokens for can either be specified as an explicit list, as file paths to get tokens for, or be left unspecified, in which case will use whatever magic `kafs(3)' decides upon. If not told what cell to get credentials for, `kafs(3)' will search for the files ThisCell and TheseCells in the locations specified in `kafs(3)' and try to get tokens for these cells and the cells specified in $HOME/.TheseCells. More usefully it will look at and ~/.TheseCells in your home directory and for each line which is a cell get afs token for these cells. The TheseCells file defines the the cells to which applications on the local client machine should try to aquire tokens for. It must reside in the directories searched by `kafs(3)' on every AFS client machine. The file is in ASCII format and contains one character string, the cell name, per line. Cell names are case sensitive, but most cell names are lower case. See manpage for `kafs(3)' for search locations of ThisCell and TheseCells. 5.2.2 How to get a KeyFile -------------------------- `ktutil -k AFSKEYFILE:KeyFile get afs@MY.REALM' or you can extract it with kadmin kadmin> ext -k AFSKEYFILE:/usr/afs/etc/KeyFile afs@My.CELL.NAME You have to make sure you have a `des-cbc-md5' encryption type since that is the enctype that will be converted. 5.2.3 How to convert a srvtab to a KeyFile ------------------------------------------ You need a `/usr/vice/etc/ThisCell' containing the cellname of your AFS-cell. `ktutil copy krb4:/root/afs-srvtab AFSKEYFILE:/usr/afs/etc/KeyFile'. If keyfile already exists, this will add the new key in afs-srvtab to KeyFile. 5.3 Using 2b tokens with AFS ============================ 5.3.1 What is 2b ? ------------------ 2b is the name of the proposal that was implemented to give basic Kerberos 5 support to AFS in rxkad. It's not real Kerberos 5 support since it still uses fcrypt for data encryption and not Kerberos encryption types. Its only possible (in all cases) to do this for DES encryption types because only then the token (the AFS equivalent of a ticket) will be smaller than the maximum size that can fit in the token cache in the OpenAFS/Transarc client. It is a so tight fit that some extra wrapping on the ASN1/DER encoding is removed from the Kerberos ticket. 2b uses a Kerberos 5 EncTicketPart instead of a Kerberos 4 ditto for the part of the ticket that is encrypted with the service's key. The client doesn't know what's inside the encrypted data so to the client it doesn't matter. To differentiate between Kerberos 4 tickets and Kerberos 5 tickets, 2b uses a special kvno, 213 for 2b tokens and 255 for Kerberos 5 tokens. Its a requirement that all AFS servers that support 2b also support native Kerberos 5 in rxkad. 5.3.2 Configuring a Heimdal kdc to use 2b tokens ------------------------------------------------ Support for 2b tokens in the kdc are turned on for specific principals by adding them to the string list option `[kdc]use_2b' in the kdc's `krb5.conf' file. [kdc] use_2b = { afs@SU.SE = yes afs/it.su.se@SU.SE = yes } 5.3.3 Configuring AFS clients for 2b support -------------------------------------------- There is no need to configure AFS clients for 2b support. The only software that needs to be installed/upgrade is a Kerberos 5 enabled `afslog'.  File: heimdal.info, Node: Things in search for a better place, Next: Kerberos 4 issues, Prev: Applications, Up: Top 6 Things in search for a better place ************************************* 6.1 Making things work on Ciscos ================================ Modern versions of Cisco IOS has some support for authenticating via Kerberos 5. This can be used both by having the router get a ticket when you login (boring), and by using Kerberos authenticated telnet to access your router (less boring). The following has been tested on IOS 11.2(12), things might be different with other versions. Old versions are known to have bugs. To make this work, you will first have to configure your router to use Kerberos (this is explained in the documentation). A sample configuration looks like the following: aaa new-model aaa authentication login default krb5-telnet krb5 enable aaa authorization exec krb5-instance kerberos local-realm FOO.SE kerberos srvtab entry host/router.foo.se 0 891725446 4 1 8 012345678901234567 kerberos server FOO.SE 10.0.0.1 kerberos instance map admin 15 This tells you (among other things) that when logging in, the router should try to authenticate with kerberised telnet, and if that fails try to verify a plain text password via a Kerberos ticket exchange (as opposed to a local database, RADIUS or something similar), and if that fails try the local enable password. If you're not careful when you specify the `login default' authentication mechanism, you might not be able to login at all. The `instance map' and `authorization exec' lines says that people with `admin' instances should be given `enabled' shells when logging in. The numbers after the principal on the `srvtab' line are principal type, time stamp (in seconds since 1970), key version number (4), keytype (1 == des), key length (always 8 with des), and then the key. To make the Heimdal KDC produce tickets that the Cisco can decode you might have to turn on the `encode_as_rep_as_tgs_rep' flag in the KDC. You will also have to specify that the router can't handle anything but `des-cbc-crc'. This can be done with the `del_enctype' command of `kadmin'. This all fine and so, but unless you have an IOS version with encryption (available only in the U.S) it doesn't really solve any problems. Sure you don't have to send your password over the wire, but since the telnet connection isn't protected it's still possible for someone to steal your session. This won't be fixed until someone adds integrity to the telnet protocol. A working solution would be to hook up a machine with a real operating system to the console of the Cisco and then use it as a backwards terminal server.  File: heimdal.info, Node: Kerberos 4 issues, Next: Windows compatibility, Prev: Things in search for a better place, Up: Top 7 Kerberos 4 issues ******************* The KDC has built-in version 4 support. It is not enabled by default, see setup how to set it up. The KDC will also have kaserver emulation and be able to handle AFS-clients that use `klog'. For more about AFS, see the section *Note AFS::. * Menu: * Principal conversion issues:: * Converting a version 4 database:: * kaserver::  File: heimdal.info, Node: Principal conversion issues, Next: Converting a version 4 database, Prev: Kerberos 4 issues, Up: Kerberos 4 issues 7.1 Principal conversion issues =============================== First, Kerberos 4 and Kerberos 5 principals are different. A version 4 principal consists of a name, an instance, and a realm. A version 5 principal has one or more components, and a realm (the terms "name" and "instance" are still used, for the first and second component, respectively). Also, in some cases the name of a version 4 principal differs from the first component of the corresponding version 5 principal. One notable example is the "host" type principals, where the version 4 name is `rcmd' (for "remote command"), and the version 5 name is `host'. For the class of principals that has a hostname as instance, there is an other major difference, Kerberos 4 uses only the first component of the hostname, whereas Kerberos 5 uses the fully qualified hostname. Because of this it can be hard or impossible to correctly convert a version 4 principal to a version 5 principal (1). The biggest problem is to know if the conversion resulted in a valid principal. To give an example, suppose you want to convert the principal `rcmd.foo'. The `rcmd' name suggests that the instance is a hostname (even if there are exceptions to this rule). To correctly convert the instance `foo' to a hostname, you have to know which host it is referring to. You can to this by either guessing (from the realm) which domain name to append, or you have to have a list of possible hostnames. In the simplest cases you can cover most principals with the first rule. If you have several domains sharing a single realm this will not usually work. If the exceptions are few you can probably come by with a lookup table for the exceptions. In a complex scenario you will need some kind of host lookup mechanism. Using DNS for this is tempting, but DNS is error prone, slow and unsafe (2). Fortunately, the KDC has a trump on hand: it can easily tell if a principal exists in the database. The KDC will use `krb5_425_conv_principal_ext' to convert principals when handling to version 4 requests. ---------- Footnotes ---------- (1) the other way is not always trivial either, but usually easier (2) at least until secure DNS is commonly available  File: heimdal.info, Node: Converting a version 4 database, Next: kaserver, Prev: Principal conversion issues, Up: Kerberos 4 issues 7.2 Converting a version 4 database =================================== If you want to convert an existing version 4 database, the principal conversion issue arises too. If you decide to convert your database once and for all, you will only have to do this conversion once. It is also possible to run a version 5 KDC as a slave to a version 4 KDC. In this case this conversion will happen every time the database is propagated. When doing this conversion, there are a few things to look out for. If you have stale entries in the database, these entries will not be converted. This might be because these principals are not used anymore, or it might be just because the principal couldn't be converted. You might also see problems with a many-to-one mapping of principals. For instance, if you are using DNS lookups and you have two principals `rcmd.foo' and `rcmd.bar', where `foo' is a CNAME for `bar', the resulting principals will be the same. Since the conversion function can't tell which is correct, these conflicts will have to be resolved manually. 7.2.1 Conversion example ------------------------ Given the following set of hosts and services: foo.se rcmd mail.foo.se rcmd, pop ftp.bar.se rcmd, ftp you have a database that consists of the following principals: `rcmd.foo', `rcmd.mail', `pop.mail', `rcmd.ftp', and `ftp.ftp'. lets say you also got these extra principals: `rcmd.gone', `rcmd.old-mail', where `gone.foo.se' was a machine that has now passed away, and `old-mail.foo.se' was an old mail machine that is now a CNAME for `mail.foo.se'. When you convert this database you want the following conversions to be done: rcmd.foo host/foo.se rcmd.mail host/mail.foo.se pop.mail pop/mail.foo.se rcmd.ftp host/ftp.bar.se ftp.ftp ftp/ftp.bar.se rcmd.gone removed rcmd.old-mail removed A `krb5.conf' that does this looks like: [realms] FOO.SE = { v4_name_convert = { host = { ftp = ftp pop = pop rcmd = host } } v4_instance_convert = { foo = foo.se ftp = ftp.bar.se } default_domain = foo.se } The `v4_name_convert' section says which names should be considered having an instance consisting of a hostname, and it also says how the names should be converted (for instance `rcmd' should be converted to `host'). The `v4_instance_convert' section says how a hostname should be qualified (this is just a hosts-file in disguise). Host-instances that aren't covered by `v4_instance_convert' are qualified by appending the contents of the `default_domain'. Actually, this example doesn't work. Or rather, it works to well. Since it has no way of knowing which hostnames are valid and which are not, it will happily convert `rcmd.gone' to `host/gone.foo.se'. This isn't a big problem, but if you have run your kerberos realm for a few years, chances are big that you have quite a few `junk' principals. If you don't want this you can remove the `default_domain' statement, but then you will have to add entries for _all_ your hosts in the `v4_instance_convert' section. Instead of doing this you can use DNS to convert instances. This is not a solution without problems, but it is probably easier than adding lots of static host entries. To enable DNS lookup you should turn on `v4_instance_resolve' in the `[libdefaults]' section. 7.2.2 Converting a database --------------------------- The database conversion is done with `hprop'. You can run this command to propagate the database to the machine called `slave-server' (which should be running a `hpropd'). hprop --source=krb4-db --master-key=/.m slave-server This command can also be to use for converting the v4 database on the server: hprop -n --source=krb4-db -d /var/kerberos/principal --master-key=/.m | hpropd -n  File: heimdal.info, Node: kaserver, Prev: Converting a version 4 database, Up: Kerberos 4 issues 7.3 kaserver ============ 7.3.1 kaserver emulation ------------------------ The Heimdal kdc can emulate a kaserver. The kaserver is a Kerberos 4 server with pre-authentication using Rx as the on-wire protocol. The kdc contains a minimalistic Rx implementation. There are three parts of the kaserver; KAA (Authentication), KAT (Ticket Granting), and KAM (Maintenance). The KAA interface and KAT interface both passes over DES encrypted data-blobs (just like the Kerberos-protocol) and thus do not need any other protection. The KAM interface uses `rxkad' (Kerberos authentication layer for Rx) for security and data protection, and is used for example for changing passwords. This part is not implemented in the kdc. Another difference between the ka-protocol and the Kerberos 4 protocol is that the pass-phrase is salted with the cellname in the `string to key' function in the ka-protocol, while in the Kerberos 4 protocol there is no salting of the password at all. To make sure AFS-compatible keys are added to each principals when they are created or their password are changed, `afs3-salt' should be added to `[kadmin]default_keys'. For more about AFS, see the section *Note AFS::. 7.3.2 Transarc AFS Windows client --------------------------------- The Transarc Windows client uses Kerberos 4 to obtain tokens, and thus does not need a kaserver. The Windows client assumes that the Kerberos server is on the same machine as the AFS-database server. If you do not like to do that you can add a small program that runs on the database servers that forward all kerberos requests to the real kerberos server. A program that does this is `krb-forward' (`ftp://ftp.stacken.kth.se/pub/projekts/krb-forward').  File: heimdal.info, Node: Windows compatibility, Next: Programming with Kerberos, Prev: Kerberos 4 issues, Up: Top 8 Windows compatibility *********************** Microsoft Windows, starting from version 2000 (formerly known as Windows NT 5), implements Kerberos 5. Their implementation, however, has some quirks, peculiarities, and bugs. This chapter is a short summary of the compatibility issues between Heimdal and various Windows versions. The big problem with the Kerberos implementation in Windows is that the available documentation is more focused on getting things to work rather than how they work, and not that useful in figuring out how things really work. It's of course subject to change all the time and mostly consists of our not so inspired guesses. Hopefully it's still somewhat useful. * Menu: * Configuring Windows to use a Heimdal KDC:: * Inter-Realm keys (trust) between Windows and a Heimdal KDC:: * Create account mappings:: * Encryption types:: * Authorisation data:: * Quirks of Windows 2000 KDC:: * Useful links when reading about the Windows::  File: heimdal.info, Node: Configuring Windows to use a Heimdal KDC, Next: Inter-Realm keys (trust) between Windows and a Heimdal KDC, Prev: Windows compatibility, Up: Windows compatibility 8.1 Configuring Windows to use a Heimdal KDC ============================================ You need the command line program called `ksetup.exe'. This program comes with the Windows Support Tools, available from either the installation CD-ROM (`SUPPORT/TOOLS/SUPPORT.CAB'), or from Microsoft web site. Starting from Windows 2008, it is already installed. This program is used to configure the Kerberos settings on a Workstation. `Ksetup' store the domain information under the registry key: `HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\LSA\Kerberos\Domains'. Use the `kadmin' program in Heimdal to create a host principal in the Kerberos realm. unix% kadmin kadmin> ank --password=password host/datan.example.com The name `datan.example.com' should be replaced with DNS name of the workstation. You must configure the workstation as a member of a workgroup, as opposed to a member in an NT domain, and specify the KDC server of the realm as follows: C:> ksetup /setdomain EXAMPLE.COM C:> ksetup /addkdc EXAMPLE.COM kdc.example.com Set the machine password, i.e. create the local keytab: C:> ksetup /SetComputerPassword password The password used in `ksetup /setmachpassword' must be the same as the password used in the `kadmin ank' command. The workstation must now be rebooted. A mapping between local NT users and Kerberos principals must be specified. You have two choices. First: C:> ksetup /mapuser user@MY.REALM nt_user This will map a user to a specific principal; this allows you to have other usernames in the realm than in your NT user database. (Don't ask me why on earth you would want that....) You can also say: C:> ksetup /mapuser * * The Windows machine will now map any user to the corresponding principal, for example `nisse' to the principal `nisse@MY.REALM'. (This is most likely what you want.)  File: heimdal.info, Node: Inter-Realm keys (trust) between Windows and a Heimdal KDC, Next: Create account mappings, Prev: Configuring Windows to use a Heimdal KDC, Up: Windows compatibility 8.2 Inter-Realm keys (trust) between Windows and a Heimdal KDC ============================================================== See also the Step-by-Step guide from Microsoft, referenced below. Install Windows, and create a new controller (Active Directory Server) for the domain. By default the trust will be non-transitive. This means that only users directly from the trusted domain may authenticate. This can be changed to transitive by using the `netdom.exe' tool. `netdom.exe' can also be used to add the trust between two realms. You need to tell Windows on what hosts to find the KDCs for the non-Windows realm with `ksetup', see *Note Configuring Windows to use a Heimdal KDC::. This needs to be done on all computers that want enable cross-realm login with `Mapped Names'. Then you need to add the inter-realm keys on the Windows KDC. Start the Domain Tree Management tool (found in Programs, Administrative tools, Active Directory Domains and Trusts). Right click on Properties of your domain, select the Trust tab. Press Add on the appropriate trust windows and enter domain name and password. When prompted if this is a non-Windows Kerberos realm, press OK. Do not forget to add trusts in both directions (if that's what you want). If you want to use `netdom.exe' instead of the Domain Tree Management tool, you do it like this: netdom trust NT.REALM.EXAMPLE.COM /Domain:EXAMPLE.COM /add /realm /passwordt:TrustPassword You also need to add the inter-realm keys to the Heimdal KDC. But take care to the encryption types and salting used for those keys. There should be no encryption type stronger than the one configured on Windows side for this relationship, itself limited to the ones supported by this specific version of Windows, nor any Kerberos 4 salted hashes, as Windows does not seem to understand them. Otherwise, the trust will not works. Here are the version-specific needed information: 1. Windows 2000: maximum encryption type is DES 2. Windows 2003: maximum encryption type is DES 3. Windows 2003RC2: maximum encryption type is RC4, relationship defaults to DES 4. Windows 2008: maximum encryption type is AES, relationship defaults to RC4 For Windows 2003RC2, to change the trust encryption type, you have to use the `ktpass', from the Windows 2003 Resource kit *service pack2*, available from Microsoft web site. C:> ktpass /MITRealmName UNIX.EXAMPLE.COM /TrustEncryp RC4 For Windows 2008, the same operation can be done with the `ksetup', installed by default. C:> ksetup /SetEncTypeAttre EXAMPLE.COM AES256-SHA1 Once the relationship is correctly configured, you can add the required inter-realm keys, using heimdal default encryption types: kadmin add krbtgt/NT.REALM.EXAMPLE.COM@EXAMPLE.COM kadmin add krbtgt/REALM.EXAMPLE.COM@NT.EXAMPLE.COM Use the same passwords for both keys. And if needed, to remove unsupported encryptions, such as the following ones for a Windows 2003RC2 server. kadmin del_enctype krbtgt/REALM.EXAMPLE.COM@NT.EXAMPLE.COM aes256-cts-hmac-sha1-96 kadmin del_enctype krbtgt/REALM.EXAMPLE.COM@NT.EXAMPLE.COM des3-cbc-sha1 kadmin del_enctype krbtgt/NT.EXAMPLE.COM@EXAMPLE.COM aes256-cts-hmac-sha1-96 kadmin del_enctype krbtgt/NT.EXAMPLE.COM@EXAMPLE.COM des3-cbc-sha1 Do not forget to reboot before trying the new realm-trust (after running `ksetup'). It looks like it might work, but packets are never sent to the non-Windows KDC.  File: heimdal.info, Node: Create account mappings, Next: Encryption types, Prev: Inter-Realm keys (trust) between Windows and a Heimdal KDC, Up: Windows compatibility 8.3 Create account mappings =========================== Start the `Active Directory Users and Computers' tool. Select the View menu, that is in the left corner just below the real menu (or press Alt-V), and select Advanced Features. Right click on the user that you are going to do a name mapping for and choose Name mapping. Click on the Kerberos Names tab and add a new principal from the non-Windows domain. This adds `authorizationNames' entry to the users LDAP entry to the Active Directory LDAP catalog. When you create users by script you can add this entry instead.  File: heimdal.info, Node: Encryption types, Next: Authorisation data, Prev: Create account mappings, Up: Windows compatibility 8.4 Encryption types ==================== Windows 2000 supports both the standard DES encryptions (`des-cbc-crc' and `des-cbc-md5') and its own proprietary encryption that is based on MD4 and RC4 that is documented in and is supposed to be described in `draft-brezak-win2k-krb-rc4-hmac-03.txt'. New users will get both MD4 and DES keys. Users that are converted from a NT4 database, will only have MD4 passwords and will need a password change to get a DES key.  File: heimdal.info, Node: Authorisation data, Next: Quirks of Windows 2000 KDC, Prev: Encryption types, Up: Windows compatibility 8.5 Authorisation data ====================== The Windows 2000 KDC also adds extra authorisation data in tickets. It is at this point unclear what triggers it to do this. The format of this data is only available under a "secret" license from Microsoft, which prohibits you implementing it. A simple way of getting hold of the data to be able to understand it better is described here. 1. Find the client example on using the SSPI in the SDK documentation. 2. Change "AuthSamp" in the source code to lowercase. 3. Build the program. 4. Add the "authsamp" principal with a known password to the database. Make sure it has a DES key. 5. Run `ktutil add' to add the key for that principal to a keytab. 6. Run `appl/test/nt_gss_server -p 2000 -s authsamp --dump-auth=FILE' where FILE is an appropriate file. 7. It should authenticate and dump for you the authorisation data in the file. 8. The tool `lib/asn1/asn1_print' is somewhat useful for analysing the data.  File: heimdal.info, Node: Quirks of Windows 2000 KDC, Next: Useful links when reading about the Windows, Prev: Authorisation data, Up: Windows compatibility 8.6 Quirks of Windows 2000 KDC ============================== There are some issues with salts and Windows 2000. Using an empty salt--which is the only one that Kerberos 4 supported, and is therefore known as a Kerberos 4 compatible salt--does not work, as far as we can tell from out experiments and users' reports. Therefore, you have to make sure you keep around keys with all the different types of salts that are required. Microsoft have fixed this issue post Windows 2003. Microsoft seems also to have forgotten to implement the checksum algorithms `rsa-md4-des' and `rsa-md5-des'. This can make Name mapping (*note Create account mappings::) fail if a `des-cbc-md5' key is used. To make the KDC return only `des-cbc-crc' you must delete the `des-cbc-md5' key from the kdc using the `kadmin del_enctype' command. kadmin del_enctype lha des-cbc-md5 You should also add the following entries to the `krb5.conf' file: [libdefaults] default_etypes = des-cbc-crc default_etypes_des = des-cbc-crc These configuration options will make sure that no checksums of the unsupported types are generated.  File: heimdal.info, Node: Useful links when reading about the Windows, Prev: Quirks of Windows 2000 KDC, Up: Windows compatibility 8.7 Useful links when reading about the Windows =============================================== See also our paper presented at the 2001 Usenix Annual Technical Conference, available in the proceedings or at `http://www.usenix.org/publications/library/proceedings/usenix01/freenix01/westerlund.html'. There are lots of texts about Kerberos on Microsoft's web site, here is a short list of the interesting documents that we have managed to find. * Step-by-Step Guide to Kerberos 5 (krb5 1.0) Interoperability: `http://www.microsoft.com/technet/prodtechnol/windows2000serv/howto/kerbstep.mspx'. Kerberos GSS-API (in Windows-eze SSPI), Windows as a client in a non-Windows KDC realm, adding unix clients to a Windows 2000 KDC, and adding cross-realm trust (*note Inter-Realm keys (trust) between Windows and a Heimdal KDC::). * Windows 2000 Kerberos Authentication: `www.microsoft.com/technet/prodtechnol/windows2000serv/deploy/confeat/kerberos.mspx'. White paper that describes how Kerberos is used in Windows 2000. * Overview of Kerberos: `http://support.microsoft.com/support/kb/articles/Q248/7/58.ASP'. Links to useful other links. * Event logging for Kerberos: `http://support.microsoft.com/support/kb/articles/Q262/1/77.ASP'. Basically it say that you can add a registry key `HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\Kerberos\Parameters\LogLevel' with value DWORD equal to 1, and then you'll get logging in the Event Logger. Other useful programs include these: * pwdump2 `http://www.bindview.com/Support/RAZOR/Utilities/Windows/pwdump2_readme.cfm'  File: heimdal.info, Node: Programming with Kerberos, Next: Migration, Prev: Windows compatibility, Up: Top 9 Programming with Kerberos *************************** See the Kerberos 5 API introduction and documentation on the Heimdal webpage.  File: heimdal.info, Node: Migration, Next: Acknowledgments, Prev: Programming with Kerberos, Up: Top 10 Migration ************ 10.1 Migration from MIT Kerberos to Heimdal =========================================== hpropd can read MIT Kerberos dump, the format is the same as used in mit-kerberos 1.0b7, and to dump that format use the following command: `kdb5_util dump -b7'. To load the MIT Kerberos dump file, use the following command: `/usr/heimdal/libexec/hprop --database=dump-file --master-key=/var/db/krb5kdc/mit_stash --source=mit-dump --decrypt --stdout | /usr/heimdal/libexec/hpropd --stdin' 10.2 General issues =================== When migrating from a Kerberos 4 KDC. 10.3 Order in what to do things: ================================ * Convert the database, check all principals that hprop complains about. `hprop -n --source=| hpropd -n' Replace with whatever source you have, like krb4-db or krb4-dump. * Run a Kerberos 5 slave for a while. * Figure out if it does everything you want it to. Make sure that all things that you use works for you. * Let a small number of controlled users use Kerberos 5 tools. Find a sample population of your users and check what programs they use, you can also check the kdc-log to check what ticket are checked out. * Burn the bridge and change the master. * Let all users use the Kerberos 5 tools by default. * Turn off services that do not need Kerberos 4 authentication. Things that might be hard to get away is old programs with support for Kerberos 4. Example applications are old Eudora installations using KPOP, and Zephyr. Eudora can use the Kerberos 4 kerberos in the Heimdal kdc.  File: heimdal.info, Node: Acknowledgments, Next: Copyrights and Licenses, Prev: Migration, Up: Top Appendix A Acknowledgments ************************** Eric Young wrote "libdes". Heimdal used to use libdes, without it kth-krb would never have existed. Since there are no longer any Eric Young code left in the library, we renamed it to libhcrypto. All functions in libhcrypto have been re-implemented or used available public domain code. The core AES function where written by Vincent Rijmen, Antoon Bosselaers and Paulo Barreto. The core DES SBOX transformation was written by Richard Outerbridge. `imath' that is used for public key crypto support is written by Michael J. Fromberger. The University of California at Berkeley initially wrote `telnet', and `telnetd'. The authentication and encryption code of `telnet' and `telnetd' was added by David Borman (then of Cray Research, Inc). The encryption code was removed when this was exported and then added back by Juha Eskelinen. The `popper' was also a Berkeley program initially. Some of the functions in `libroken' also come from Berkeley by way of NetBSD/FreeBSD. `editline' was written by Simmule Turner and Rich Salz. Heimdal contains a modifed copy. The `getifaddrs' implementation for Linux was written by Hideaki YOSHIFUJI for the Usagi project. The `pkcs11.h' headerfile was written by the Scute project. Bugfixes, documentation, encouragement, and code has been contributed by: Alexander Boström Allan McRae Andrew Bartlett Andrew Cobaugh Andrew Tridge Anton Lundin Asanka Herath Björn Grönvall Björn Sandell Björn Schlögl Brandon S. Allbery KF8NH Brian A May Buck Huppmann Cacdric Schieli Chaskiel M Grundman Christos Zoulas Cizzi Storm Daniel Kouril David Love David Markey David R Boldt Derrick J Brashear Donald Norwood Douglas E Engert Frank van der Linden Gabor Gombas Guido Günther Guillaume Rousse Harald Barth Ingo Schwarze Jacques A. Vidrine Jaideep Padhye Jan Rekorajski Jason McIntyre Jeffrey Altman Jelmer Vernooij Joerg Pulz Johan Danielsson Johan Gadsjö Johan Ihrén John Center Jun-ichiro itojun Hagino KAMADA Ken'ichi Kamen Mazdrashki Karolin Seeger Ken Hornstein Love Hörnquist Åstrand Luke Howard Magnus Ahltorp Magnus Holmberg Marc Horowitz Mario Strasser Mark Eichin Martin von Gagern Matthias Dieter Wallnöfer Matthieu Patou Mattias Amnefelt Michael B Allen Michael Fromberger Michal Vocu Milosz Kmieciak Miroslav Ruda Mustafa A. Hashmi Nicolas Williams Patrik Lundin Petr Holub Phil Fisher Rafal Malinowski Ragnar Sundblad Rainer Toebbicke Richard Nyberg Roland C. Dowdeswell Roman Divacky Russ Allbery Sho Hosoda, 細田 将 Simon Wilkinson Stefan Metzmacher Ted Percival Tom Payerle Victor Guerra Zeqing Xia Åke Sandgren and we hope that those not mentioned here will forgive us. All bugs were introduced by ourselves.  File: heimdal.info, Node: Copyrights and Licenses, Prev: Acknowledgments, Up: Top Appendix B Copyrights and Licenses ********************************** Kungliga Tekniska Högskolan ============================ Copyright (c) 1997-2011 Kungliga Tekniska Högskolan (Royal Institute of Technology, Stockholm, Sweden). All rights reserved. Portions Copyright (c) 2009 Apple Inc. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the Institute nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Massachusetts Institute of Technology ===================================== The parts of the libtelnet that handle Kerberos. Copyright (C) 1990 by the Massachusetts Institute of Technology Export of this software from the United States of America may require a specific license from the United States Government. It is the responsibility of any person or organization contemplating export to obtain such a license before exporting. WITHIN THAT CONSTRAINT, permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the name of M.I.T. not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. M.I.T. makes no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty. The Regents of the University of California =========================================== The parts of the libroken, most of libtelnet, telnet, ftp, and popper. Copyright (c) 1988, 1990, 1993 The Regents of the University of California. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. The Regents of the University of California. ============================================ libedit Copyright (c) 1992, 1993 The Regents of the University of California. All rights reserved. This code is derived from software contributed to Berkeley by Christos Zoulas of Cornell University. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of the University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. TomsFastMath / LibTomMath ========================= Tom's fast math (bignum support) and LibTomMath LibTomMath is hereby released into the Public Domain. Doug Rabson =========== GSS-API mechglue layer. Copyright (c) 2005 Doug Rabson All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. PADL Software Pty Ltd ===================== GSS-API CFX, SPNEGO, naming extensions, API extensions. KCM credential cache. HDB LDAP backend. Copyright (c) 2003-2011, PADL Software Pty Ltd. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. Neither the name of PADL Software nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Marko Kreen =========== Fortuna in libhcrypto Copyright (c) 2005 Marko Kreen All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. NTT (Nippon Telegraph and Telephone Corporation) ================================================ Camellia in libhcrypto Copyright (c) 2006,2007 NTT (Nippon Telegraph and Telephone Corporation) . All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer as the first lines of this file unmodified. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY NTT ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL NTT BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. The NetBSD Foundation, Inc. =========================== vis.c in libroken Copyright (c) 1999, 2005 The NetBSD Foundation, Inc. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Vincent Rijmen, Antoon Bosselaers, Paulo Barreto ================================================ AES in libhcrypto rijndael-alg-fst.c @version 3.0 (December 2000) Optimised ANSI C code for the Rijndael cipher (now AES) @author Vincent Rijmen @author Antoon Bosselaers @author Paulo Barreto This code is hereby placed in the public domain. THIS SOFTWARE IS PROVIDED BY THE AUTHORS ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Apple, Inc ========== kdc/announce.c Copyright (c) 2008 Apple Inc. All Rights Reserved. Export of this software from the United States of America may require a specific license from the United States Government. It is the responsibility of any person or organization contemplating export to obtain such a license before exporting. WITHIN THAT CONSTRAINT, permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the name of Apple Inc. not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. Apple Inc. makes no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty. THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. Richard Outerbridge =================== DES core in libhcrypto D3DES (V5.09) - A portable, public domain, version of the Data Encryption Standard. Written with Symantec's THINK (Lightspeed) C by Richard Outerbridge. Thanks to: Dan Hoey for his excellent Initial and Inverse permutation code; Jim Gillogly & Phil Karn for the DES key schedule code; Dennis Ferguson, Eric Young and Dana How for comparing notes; and Ray Lau, for humouring me on. Copyright (c) 1988,1989,1990,1991,1992 by Richard Outerbridge. (GEnie : OUTER; CIS : [71755,204]) Graven Imagery, 1992. Secure Endpoints Inc ==================== Windows support Copyright (c) 2009, Secure Endpoints Inc. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: - Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Novell, Inc =========== lib/hcrypto/test_dh.c Copyright (c) 2007, Novell, Inc. Author: Matthias Koenig All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the Novell nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  Tag Table: Node: Top212 Node: Introduction1708 Node: What is Kerberos?4517 Node: Building and Installing9630 Node: Setting up a realm9957 Node: Configuration file10945 Node: Creating the database14013 Node: Modifying the database16945 Node: Checking the setup18538 Node: keytabs19393 Node: Serving Kerberos 4/524/kaserver20261 Node: Remote administration21805 Node: Password changing23735 Node: Testing clients and servers27923 Node: Slave Servers28251 Node: Incremental propagation30006 Node: Encryption types and salting33250 Node: Credential cache server - KCM35427 Node: Cross realm37411 Node: Transit policy39957 Node: Setting up DNS46734 Node: Using LDAP to store the database49209 Node: Providing Kerberos credentials to servers and programs55214 Node: Setting up PK-INIT57312 Node: Debugging Kerberos problems69791 Node: Applications70222 Node: Authentication modules70422 Node: Digital SIA71016 Node: IRIX75400 Node: AFS76690 Node: Things in search for a better place80444 Node: Kerberos 4 issues83173 Node: Principal conversion issues83680 Ref: Principal conversion issues-Footnote-185911 Ref: Principal conversion issues-Footnote-285979 Node: Converting a version 4 database86032 Node: kaserver90362 Node: Windows compatibility92183 Node: Configuring Windows to use a Heimdal KDC93269 Node: Inter-Realm keys (trust) between Windows and a Heimdal KDC95339 Node: Create account mappings99010 Node: Encryption types99762 Node: Authorisation data100362 Node: Quirks of Windows 2000 KDC101509 Node: Useful links when reading about the Windows102803 Node: Programming with Kerberos104607 Node: Migration104857 Node: Acknowledgments106618 Node: Copyrights and Licenses109544  End Tag Table