main/krb5: security fix (CVE-2018-20217)

Fixes #9805

2 files changed, 79 insertions, 11 deletions

diff --git a/main/krb5/APKBUILD b/main/krb5/APKBUILD
index a6f8c2af2a..3c96964968 100644
--- a/main/krb5/APKBUILD
+++ b/main/krb5/APKBUILD
@@ -1,7 +1,7 @@
 # Maintainer: Natanael Copa <ncopa@alpinelinux.org>
 pkgname=krb5
 pkgver=1.14.3
-pkgrel=2
+pkgrel=3
 
 case $pkgver in
 *.*.*) _ver=${pkgver%.*};;
@@ -22,12 +22,17 @@ subpackages="$pkgname-dev $pkgname-doc $pkgname-server
 	$pkgname-server-ldap:ldap $pkgname-pkinit $pkgname-libs"
 source="http://web.mit.edu/kerberos/dist/krb5/${_ver}/krb5-$pkgver.tar.gz
 	mit-krb5_krb5-config_LDFLAGS.patch
+	CVE-2018-20217.patch
 
 	krb5kadmind.initd
 	krb5kdc.initd
 	krb5kpropd.initd
 	"
 
+# secfixes:
+#   1.14.3-r3:
+#     - CVE-2018-20217
+
 _builddir="$srcdir"/krb5-$pkgver
 unpack() {
 	default_unpack
@@ -117,18 +122,9 @@ libs() {
 	mkdir -p "$subpkgdir"/usr/
 	mv "$pkgdir"/usr/lib "$subpkgdir"/usr/ || return 1
 }
-md5sums="f76e4f8a3c95bb59980dd5ef4b48aea9  krb5-1.14.3.tar.gz
-c84a0c7d8014e3528524956ffdd1c3e9  mit-krb5_krb5-config_LDFLAGS.patch
-9c0e3bac122326cdbbbac068056ee8af  krb5kadmind.initd
-71131479c07a2d89b30a2ea18dd64e74  krb5kdc.initd
-d94873a6a1ac6277adf2d25458eda9e5  krb5kpropd.initd"
-sha256sums="cd4620d520cf0df0dd8791309912df2bb20fcba76790b9fba4e25c1da08ff2c9  krb5-1.14.3.tar.gz
-84007c7423f67db7a8b248b9643c49ef25f2d56ce15c2574eb41ecbf51bcd3f2  mit-krb5_krb5-config_LDFLAGS.patch
-213a5b04f091e4644e856aabc38da586bd86c4616ab15f00eefca52fca7137d6  krb5kadmind.initd
-577842c7fe4639a8e9dd349da40e514284dd53440bb71be58283faaf18508f9a  krb5kdc.initd
-1644639d83791bd871f3c89a53a7052ab52994d3ef03d1d675d4217130c1fa94  krb5kpropd.initd"
 sha512sums="97f42bb7e0f69e337b949b451bf925f604e7ef9336c32bd4d62224a8c4a37e631f5a6fc01016bbdf268bbb60fa58712e244e00a1ab5a8bceede6a676482235aa  krb5-1.14.3.tar.gz
 5a3782ff17b383f8cd0415fd13538ab56afd788130d6ad640e9f2682b7deaae7f25713ce358058ed771091040dccf62a3bc87e6fd473d505ec189a95debcc801  mit-krb5_krb5-config_LDFLAGS.patch
+30891c26b191ced94956bea869996a78147f4b87fb9bb511790bf20ff9a04fe5075e3584e03b19206327b954a2ad630b4f90cd443d5855481d521c640fe9d125  CVE-2018-20217.patch
 43b9885b7eb8d0d60920def688de482f2b1701288f9acb1bb21dc76b2395428ff304961959eb04ba5eafd0412bae35668d6d2c8223424b9337bc051eadf51682  krb5kadmind.initd
 ede15f15bbbc9d0227235067abe15245bb9713aea260d397379c63275ce74aea0db6c91c15d599e40c6e89612d76f3a0f8fdd21cbafa3f30d426d4310d3e2cec  krb5kdc.initd
 45be0d421efd41e9dd056125a750c90856586e990317456b68170d733b03cba9ecd18ab87603b20e49575e7839fb4a6d628255533f2631f9e8ddb7f3cc493a90  krb5kpropd.initd"
diff --git a/main/krb5/CVE-2018-20217.patch b/main/krb5/CVE-2018-20217.patch
new file mode 100644
index 0000000000..80f2d55058
--- /dev/null
+++ b/main/krb5/CVE-2018-20217.patch
@@ -0,0 +1,72 @@
+From 5e6d1796106df8ba6bc1973ee0917c170d929086 Mon Sep 17 00:00:00 2001
+From: Isaac Boukris <iboukris@gmail.com>
+Date: Mon, 3 Dec 2018 02:33:07 +0200
+Subject: [PATCH] Ignore password attributes for S4U2Self requests
+
+For consistency with Windows KDCs, allow protocol transition to work
+even if the password has expired or needs changing.
+
+Also, when looking up an enterprise principal with an AS request,
+treat ERR_KEY_EXP as confirmation that the client is present in the
+realm.
+
+[ghudson@mit.edu: added comment in kdc_process_s4u2self_req(); edited
+commit message]
+
+ticket: 8763 (new)
+tags: pullup
+target_version: 1.17
+---
+ src/kdc/kdc_util.c           | 5 +++++
+ src/lib/krb5/krb/s4u_creds.c | 2 +-
+ src/tests/gssapi/t_s4u.py    | 8 ++++++++
+ 3 files changed, 14 insertions(+), 1 deletion(-)
+
+diff --git a/src/kdc/kdc_util.c b/src/kdc/kdc_util.c
+index 6d53173fb0..6517a213cd 100644
+--- a/src/kdc/kdc_util.c
++++ b/src/kdc/kdc_util.c
+@@ -1607,6 +1607,11 @@ kdc_process_s4u2self_req(kdc_realm_t *kdc_active_realm,
+ 
+         memset(&no_server, 0, sizeof(no_server));
+ 
++        /* Ignore password expiration and needchange attributes (as Windows
++         * does), since S4U2Self is not password authentication. */
++        princ->pw_expiration = 0;
++        clear(princ->attributes, KRB5_KDB_REQUIRES_PWCHANGE);
++
+         code = validate_as_request(kdc_active_realm, request, *princ,
+                                    no_server, kdc_time, status, &e_data);
+         if (code) {
+diff --git a/src/lib/krb5/krb/s4u_creds.c b/src/lib/krb5/krb/s4u_creds.c
+index d2fdcb3f16..614ed41908 100644
+--- a/src/lib/krb5/krb/s4u_creds.c
++++ b/src/lib/krb5/krb/s4u_creds.c
+@@ -116,7 +116,7 @@ s4u_identify_user(krb5_context context,
+     code = k5_get_init_creds(context, &creds, &client, NULL, NULL, 0, NULL,
+                              opts, krb5_get_as_key_noop, &userid, &use_master,
+                              NULL);
+-    if (code == 0 || code == KRB5_PREAUTH_FAILED) {
++    if (!code || code == KRB5_PREAUTH_FAILED || code == KRB5KDC_ERR_KEY_EXP) {
+         *canon_user = userid.user;
+         userid.user = NULL;
+         code = 0;
+diff --git a/src/tests/gssapi/t_s4u.py b/src/tests/gssapi/t_s4u.py
+index fd29e1a270..84f3fbd752 100755
+--- a/src/tests/gssapi/t_s4u.py
++++ b/src/tests/gssapi/t_s4u.py
+@@ -19,6 +19,14 @@
+ # Get forwardable creds for service1 in the default cache.
+ realm.kinit(service1, None, ['-f', '-k'])
+ 
++# Try S4U2Self for user with a restricted password.
++realm.run([kadminl, 'modprinc', '+needchange', realm.user_princ])
++realm.run(['./t_s4u', 'e:user', '-'])
++realm.run([kadminl, 'modprinc', '-needchange',
++          '-pwexpire', '1/1/2000', realm.user_princ])
++realm.run(['./t_s4u', 'e:user', '-'])
++realm.run([kadminl, 'modprinc', '-pwexpire', 'never', realm.user_princ])
++
+ # Try krb5 -> S4U2Proxy with forwardable user creds.  This should fail
+ # at the S4U2Proxy step since the DB2 back end currently has no
+ # support for allowing it.