[arch-commits] Commit in pam/trunk (4 files)
Tobias Powalowski
tpowa at archlinux.org
Wed Aug 12 19:24:28 UTC 2020
Date: Wednesday, August 12, 2020 @ 19:24:27
Author: tpowa
Revision: 393557
Prevent determining if user exists through timing, Fix pam_faillock, Backup etc/security/faillock.conf, Drop cracklib dependency
Added:
pam/trunk/0e9b286afe1224b91ff00936058b084ad4b776e4.patch
pam/trunk/395915dae1571e10e2766c999974de864655ea3a.patch
pam/trunk/af0faf666c5008e54dfe43684f210e3581ff1bca.patch
Modified:
pam/trunk/PKGBUILD
------------------------------------------------+
0e9b286afe1224b91ff00936058b084ad4b776e4.patch | 31 ++++++++
395915dae1571e10e2766c999974de864655ea3a.patch | 47 ++++++++++++
PKGBUILD | 26 +++++--
af0faf666c5008e54dfe43684f210e3581ff1bca.patch | 85 +++++++++++++++++++++++
4 files changed, 184 insertions(+), 5 deletions(-)
Added: 0e9b286afe1224b91ff00936058b084ad4b776e4.patch
===================================================================
--- 0e9b286afe1224b91ff00936058b084ad4b776e4.patch (rev 0)
+++ 0e9b286afe1224b91ff00936058b084ad4b776e4.patch 2020-08-12 19:24:27 UTC (rev 393557)
@@ -0,0 +1,31 @@
+From 0e9b286afe1224b91ff00936058b084ad4b776e4 Mon Sep 17 00:00:00 2001
+From: ikerexxe <ipedrosa at redhat.com>
+Date: Tue, 16 Jun 2020 14:44:04 +0200
+Subject: [PATCH] pam_usertype: avoid determining if user exists
+
+Taking a look at the time for the password prompt to appear it was
+possible to determine if a user existed in a system. Solved it by
+matching the runtime until the password prompt was shown by always
+checking the password hash for an existing and a non-existing user.
+
+Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1629598
+---
+ modules/pam_usertype/pam_usertype.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/modules/pam_usertype/pam_usertype.c b/modules/pam_usertype/pam_usertype.c
+index 2807c306..d03b73b5 100644
+--- a/modules/pam_usertype/pam_usertype.c
++++ b/modules/pam_usertype/pam_usertype.c
+@@ -139,8 +139,11 @@ pam_usertype_get_uid(struct pam_usertype_opts *opts,
+ "error retrieving information about user %s", username);
+ }
+
++ pam_modutil_getpwnam(pamh, "root");
++
+ return PAM_USER_UNKNOWN;
+ }
++ pam_modutil_getpwnam(pamh, "pam_usertype_non_existent:");
+
+ *_uid = pwd->pw_uid;
+
Added: 395915dae1571e10e2766c999974de864655ea3a.patch
===================================================================
--- 395915dae1571e10e2766c999974de864655ea3a.patch (rev 0)
+++ 395915dae1571e10e2766c999974de864655ea3a.patch 2020-08-12 19:24:27 UTC (rev 393557)
@@ -0,0 +1,47 @@
+From 395915dae1571e10e2766c999974de864655ea3a Mon Sep 17 00:00:00 2001
+From: ikerexxe <ipedrosa at redhat.com>
+Date: Mon, 15 Jun 2020 09:52:11 +0200
+Subject: [PATCH] pam_faillock: change /run/faillock/$USER permissions to 0660
+
+Nowadays, /run/faillock/$USER files have user:root ownership and 0600
+permissions. This forces the process that writes to these files to have
+CAP_DAC_OVERRIDE capabilites. Just by changing the permissions to 0660
+the capability can be removed, which leads to a more secure system.
+
+Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1661822
+---
+ modules/pam_faillock/faillock.c | 14 +++++++++++++-
+ 1 file changed, 13 insertions(+), 1 deletion(-)
+
+diff --git a/modules/pam_faillock/faillock.c b/modules/pam_faillock/faillock.c
+index e492f5f9..4ea94cbe 100644
+--- a/modules/pam_faillock/faillock.c
++++ b/modules/pam_faillock/faillock.c
+@@ -76,7 +76,7 @@ open_tally (const char *dir, const char *user, uid_t uid, int create)
+ flags |= O_CREAT;
+ }
+
+- fd = open(path, flags, 0600);
++ fd = open(path, flags, 0660);
+
+ free(path);
+
+@@ -88,6 +88,18 @@ open_tally (const char *dir, const char *user, uid_t uid, int create)
+ if (st.st_uid != uid) {
+ ignore_return(fchown(fd, uid, -1));
+ }
++
++ /*
++ * If umask is set to 022, as will probably in most systems, then the
++ * group will not be able to write to the file. So, change the file
++ * permissions just in case.
++ * Note: owners of this file are user:root, so if the permissions are
++ * not changed the root process writing to this file will require
++ * CAP_DAC_OVERRIDE.
++ */
++ if (!(st.st_mode & S_IWGRP)) {
++ ignore_return(fchmod(fd, 0660));
++ }
+ }
+ }
+
Modified: PKGBUILD
===================================================================
--- PKGBUILD 2020-08-12 18:48:08 UTC (rev 393556)
+++ PKGBUILD 2020-08-12 19:24:27 UTC (rev 393557)
@@ -3,16 +3,20 @@
pkgname=pam
pkgver=1.4.0
-pkgrel=2
+pkgrel=3
pkgdesc="PAM (Pluggable Authentication Modules) library"
arch=('x86_64')
license=('GPL2')
url="http://linux-pam.org"
-depends=('glibc' 'cracklib' 'libtirpc' 'pambase' 'audit')
+depends=('glibc' 'libtirpc' 'pambase' 'audit')
makedepends=('flex' 'w3m' 'docbook-xml>=4.4' 'docbook-xsl')
-backup=(etc/security/{access.conf,group.conf,limits.conf,namespace.conf,namespace.init,pam_env.conf,time.conf} etc/environment)
+backup=(etc/security/{access.conf,faillock.conf,group.conf,limits.conf,namespace.conf,namespace.init,pam_env.conf,time.conf} etc/environment)
source=(https://github.com/linux-pam/linux-pam/releases/download/v$pkgver/Linux-PAM-$pkgver.tar.xz
- https://github.com/linux-pam/linux-pam/releases/download/v$pkgver/Linux-PAM-$pkgver.tar.xz.asc)
+ https://github.com/linux-pam/linux-pam/releases/download/v$pkgver/Linux-PAM-$pkgver.tar.xz.asc
+ 395915dae1571e10e2766c999974de864655ea3a.patch
+ af0faf666c5008e54dfe43684f210e3581ff1bca.patch
+ 0e9b286afe1224b91ff00936058b084ad4b776e4.patch
+ $pkgname.tmpfiles)
validpgpkeys=(
'8C6BFD92EE0F42EDF91A6A736D1A7F052E5924BB' # Thorsten Kukuk
'296D6F29A020808E8717A8842DB5BD89A340AEB7' #Dimitry V. Levin <ldv at altlinux.org>
@@ -19,10 +23,21 @@
)
sha256sums=('cd6d928c51e64139be3bdb38692c68183a509b83d4f2c221024ccd4bcddfd034'
- 'SKIP')
+ 'SKIP'
+ 'cd2440d7bec55fa91e499060c0bf248f4fd20e7a0ef613eb7a06ee083f7ce21b'
+ 'ac3e1d307756f5975587a7846500414c02d2b60acb271017b9c7aa6f47c89875'
+ '68f81b67dde5ee6003524b6b14e2d6f27edcfc0a2bde4c55a1cacbc6e299c207'
+ '5631f224e90c4f0459361c2a5b250112e3a91ba849754bb6f67d69d683a2e5ac')
options=('!emptydirs')
+prepare() {
+ cd Linux-PAM-$pkgver
+ patch -p1 -i ../395915dae1571e10e2766c999974de864655ea3a.patch
+ patch -p1 -i ../af0faf666c5008e54dfe43684f210e3581ff1bca.patch
+ patch -p1 -i ../0e9b286afe1224b91ff00936058b084ad4b776e4.patch
+}
+
build() {
cd Linux-PAM-$pkgver
./configure --libdir=/usr/lib --sbindir=/usr/bin --disable-db
@@ -30,6 +45,7 @@
}
package() {
+ install -Dm 644 $pkgname.tmpfiles "$pkgdir"/usr/lib/tmpfiles.d/$pkgname.conf
cd Linux-PAM-$pkgver
make DESTDIR="$pkgdir" SCONFIGDIR=/etc/security install
Added: af0faf666c5008e54dfe43684f210e3581ff1bca.patch
===================================================================
--- af0faf666c5008e54dfe43684f210e3581ff1bca.patch (rev 0)
+++ af0faf666c5008e54dfe43684f210e3581ff1bca.patch 2020-08-12 19:24:27 UTC (rev 393557)
@@ -0,0 +1,85 @@
+From af0faf666c5008e54dfe43684f210e3581ff1bca Mon Sep 17 00:00:00 2001
+From: ikerexxe <ipedrosa at redhat.com>
+Date: Tue, 16 Jun 2020 14:32:36 +0200
+Subject: [PATCH] pam_unix: avoid determining if user exists
+
+Taking a look at the time for the password prompt to appear it was
+possible to determine if a user existed in a system. Solved it by
+matching the runtime until the password prompt was shown by always
+checking the password hash for an existing and a non-existing user.
+
+Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1629598
+---
+ modules/pam_unix/passverify.c | 6 ++++++
+ modules/pam_unix/support.c | 33 ++++++++++++++++++++++++++-------
+ 2 files changed, 32 insertions(+), 7 deletions(-)
+
+diff --git a/modules/pam_unix/passverify.c b/modules/pam_unix/passverify.c
+index a571b4f7..7455eae6 100644
+--- a/modules/pam_unix/passverify.c
++++ b/modules/pam_unix/passverify.c
+@@ -1096,6 +1096,12 @@ helper_verify_password(const char *name, const char *p, int nullok)
+ if (pwd == NULL || hash == NULL) {
+ helper_log_err(LOG_NOTICE, "check pass; user unknown");
+ retval = PAM_USER_UNKNOWN;
++ } else if (p[0] == '\0' && nullok) {
++ if (hash[0] == '\0') {
++ retval = PAM_SUCCESS;
++ } else {
++ retval = PAM_AUTH_ERR;
++ }
+ } else {
+ retval = verify_pwd_hash(p, hash, nullok);
+ }
+diff --git a/modules/pam_unix/support.c b/modules/pam_unix/support.c
+index 41db1f04..dc67238c 100644
+--- a/modules/pam_unix/support.c
++++ b/modules/pam_unix/support.c
+@@ -601,6 +601,8 @@ _unix_blankpasswd (pam_handle_t *pamh, unsigned long long ctrl, const char *name
+ char *salt = NULL;
+ int daysleft;
+ int retval;
++ int execloop = 1;
++ int nonexistent = 1;
+
+ D(("called"));
+
+@@ -624,14 +626,31 @@ _unix_blankpasswd (pam_handle_t *pamh, unsigned long long ctrl, const char *name
+
+ /* UNIX passwords area */
+
+- retval = get_pwd_hash(pamh, name, &pwd, &salt);
++ /*
++ * Execute this loop twice: one checking the password hash of an existing
++ * user and another one for a non-existing user. This way the runtimes
++ * are equal, making it more difficult to differentiate existing from
++ * non-existing users.
++ */
++ while (execloop) {
++ retval = get_pwd_hash(pamh, name, &pwd, &salt);
+
+- if (retval == PAM_UNIX_RUN_HELPER) {
+- /* salt will not be set here so we can return immediately */
+- if (_unix_run_helper_binary(pamh, NULL, ctrl, name) == PAM_SUCCESS)
+- return 1;
+- else
+- return 0;
++ if (retval == PAM_UNIX_RUN_HELPER) {
++ execloop = 0;
++ if(nonexistent) {
++ get_pwd_hash(pamh, "pam_unix_non_existent:", &pwd, &salt);
++ }
++ /* salt will not be set here so we can return immediately */
++ if (_unix_run_helper_binary(pamh, NULL, ctrl, name) == PAM_SUCCESS)
++ return 1;
++ else
++ return 0;
++ } else if (retval == PAM_USER_UNKNOWN) {
++ name = "root";
++ nonexistent = 0;
++ } else {
++ execloop = 0;
++ }
+ }
+
+ /* Does this user have a password? */
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