The current development status of this feature was discussed and it's scope will be limited for the first release. SC authentication will be LDAP-based (details in https://bugzilla.redhat.com/show_bug.cgi?id=854396#c6).

Kerberos authentication or automatic retrieval of user TGT after authentication (pkinit) will be postponed, given the functionality currently requires special certificate extension (id-pkinit-san) in order to properly map certificates and (user) principals. This is not guaranteed with the primary supported cards (CAC), so we would first need to work on extending our Kerberos backend to provide the mapping ourselves.

Fixed upstream
master:
https://pagure.io/freeipa/c/da880decfedc66f9d0d2734dcb86c23a8866f603
https://pagure.io/freeipa/c/c4156041feb9c48598427ad59e43313b9c7327bb
ipa-4-5:
https://pagure.io/freeipa/c/cfaaf4e821338dbc146dd49d3c22978165d2e329
https://pagure.io/freeipa/c/5a1ce1fbaa6c7a85bd1bee2a70b8b22509ede7c7

Note that the RFE is implemented, it works with new installs but there are still bugs in upgrades, which have to be fixed. But let's put these patches to current build to allow early testing of at least this.

Fixed upstream
master:
https://pagure.io/freeipa/c/2dda1acf44dc96e660e81baadee9c3a54bf05eb0
ipa-4-5:
https://pagure.io/freeipa/c/2d246000ef2d715fab464b8ef71fdb3731da127e

We need to bump Requires on krb5 to 1.15.1-4 which resolves bug 1428484, moving back to ASSIGNED.

Fixed upstream

master:
https://pagure.io/freeipa/c/0f42670afa935801c25bc66f733a8d1b90ea5a0b

ipa-4-5:
https://pagure.io/freeipa/c/ec3a2a6063beb4ec96796b66abb82476a5c7bd0f

Verified.

Version ::
ipa-client-4.5.0-8.el7.x86_64
sssd-1.15.2-17.el7.x86_64

Results ::

### First the options for enabling/disabling anonymous pkinit support
### Also shows anonymous pkinit working

[root@dhcp129-184 ~]# ipa pkinit-anonymous enable

[root@dhcp129-184 ~]# kdestroy -A

[root@dhcp129-184 ~]# kinit -n

[root@dhcp129-184 ~]# ARMOR_CCACHE=$(klist|grep cache:|cut -d' ' -f3-)

[root@dhcp129-184 ~]# kinit -T $ARMOR_CCACHE admin
Password for admin: 

[root@dhcp129-184 ~]# ipa pkinit-anonymous disable

[root@dhcp129-184 ~]# kdestroy -A

### Also, to be thorough, a test with kinit using the smart card:

[root@dhcp129-184 ~]# kinit -X X509_user_identity=PKCS11:module_name=/usr/lib64/opensc-pkcs11.so demosc1
demosc1 (OpenSC Card)            PIN: 

[root@dhcp129-184 ~]# klist
Ticket cache: KEYRING:persistent:0:krb_ccache_7XZIAfK
Default principal: demosc1

Valid starting       Expires              Service principal
05/08/2017 12:06:24  05/09/2017 12:06:19  krbtgt/TESTRELM.TEST


[root@dhcp129-184 ~]# kinit -n
kinit: Client's credentials have been revoked while getting initial credentials

[root@dhcp129-184 ~]# kinit admin
Password for admin: 


### Now showing that we get a kerberos ticket when logging in using a smart card
### This example uses SU but, we saw the same behavior work with GDM logins

### First I setup users with and without certs.  the certs were generated by IPA.  The Smart Card had the users key and cert added manually with pkcs15-* commands.
### scuser107 does not have cert or certmapdata added
### demosc1 has both cert and certmapdata
### demosc2 has certmapdata only

[root@dhcp129-184 ~]# ipa user-show demosc1 |sed 's/MII.*$/MII.../'
  User login: demosc1
  First name: demosc
  Last name: demosc1
  Home directory: /home/demosc1
  Login shell: /bin/sh
  Principal name: demosc1
  Principal alias: demosc1
  Email address: demosc1
  UID: 576400131
  GID: 576400131
  Certificate: MII...
  Certificate mapping data: X509:<I>O=TESTRELM.TEST,CN=Certificate Authority<S>O=TESTRELM.TEST,CN=demosc1
  Account disabled: False
  Password: True
  Member of groups: ipausers
  Kerberos keys available: True

[root@dhcp129-184 ~]# ipa user-show demosc2 |sed 's/MII.*$/MII.../'
  User login: demosc2
  First name: demosc2
  Last name: demosc2
  Home directory: /home/demosc2
  Login shell: /bin/sh
  Principal name: demosc2
  Principal alias: demosc2
  Email address: demosc2
  UID: 576400132
  GID: 576400132
  Certificate mapping data: X509:<I>O=TESTRELM.TEST,CN=Certificate Authority<S>O=TESTRELM.TEST,CN=demosc1
  Account disabled: False
  Password: True
  Member of groups: ipausers
  Kerberos keys available: True

[root@dhcp129-184 ~]# ipa user-show scuser107 |sed 's/MII.*$/MII.../'
  User login: scuser107
  First name: f
  Last name: l
  Home directory: /home/scuser107
  Login shell: /bin/sh
  Principal name: scuser107
  Principal alias: scuser107
  Email address: scuser107
  UID: 576400135
  GID: 576400135
  Account disabled: False
  Password: True
  Member of groups: ipausers
  Kerberos keys available: True

[root@dhcp129-184 ~]# ipa certmaprule-find combined
-------------------------------------------
1 Certificate Identity Mapping Rule matched
-------------------------------------------
  Rule name: combined
  Mapping rule: (|(userCertificate;binary={cert!bin})(ipacertmapdata=X509:<I>{issuer_dn!nss_x500}<S>{subject_dn!nss_x500}))
  Matching rule: <ISSUER>CN=Certificate Authority,O=TESTRELM.TEST
  Enabled: TRUE
----------------------------
Number of entries returned 1
----------------------------

####################################################################
### Now the test showing su ask for pin and getting kerberos ticket
####################################################################

[root@dhcp129-184 ~]# su - demosc1 -c 'kdestroy -A'

[root@dhcp129-184 ~]# su - demosc1 -c klist
klist: Credentials cache keyring 'persistent:576400131:krb_ccache_Yova6yX' not found

[root@dhcp129-184 ~]# su - scuser107 
Last login: Mon May  8 11:56:17 MDT 2017 on pts/0

-sh-4.2$ whoami
scuser107

-sh-4.2$ su - demosc1 -c 'klist'
PIN for demosc1 (OpenSC Card) for user demosc1
Ticket cache: KEYRING:persistent:576400131:krb_ccache_ndRgXGh
Default principal: demosc1

Valid starting       Expires              Service principal
05/08/2017 11:57:34  05/09/2017 11:57:32  krbtgt/TESTRELM.TEST

### Then as second user with certmapdata:

[root@dhcp129-184 ~]# su - demosc2 -c 'kdestroy -A'

[root@dhcp129-184 ~]# su - demosc2 -c 'klist'
klist: Credentials cache keyring 'persistent:576400132:krb_ccache_ZAnYcCH' not found

[root@dhcp129-184 ~]# su - scuser107 
Last login: Mon May  8 11:57:11 MDT 2017 on pts/0

-sh-4.2$ whoami
scuser107

-sh-4.2$ su - demosc2 -c 'klist'
PIN for demosc1 (OpenSC Card) for user demosc2
Ticket cache: KEYRING:persistent:576400132:krb_ccache_9Or3NnY
Default principal: demosc2

Valid starting       Expires              Service principal
05/08/2017 11:59:07  05/09/2017 11:59:05  krbtgt/TESTRELM.TEST

Please note that Red Hat officially released public RHEL-7.4 Beta this week, as announced here:
https://www.redhat.com/en/about/blog/red-hat-enterprise-linux-74-beta-now-available

The new RHEL-7.4 release includes a lot of new IdM functionality, including this RFE. Highlights can be found in RHEL-7.4 Release Notes, especially in the Authentication & Interoperability chapter:
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7-Beta/html/7.4_Release_Notes/new_features_authentication_and_interoperability.html

IdM Engineering team would like to encourage everyone interested in this new functionality (and especially customers or community members requesting it) to try Beta and provide us with your feedback!

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2017:2304