pam_access: always match local address and clarify LOCAL keyword behaviour

Resolves: RHEL-65223

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
This commit is contained in:
Iker Pedrosa 2024-11-04 09:58:27 +01:00
parent 0b8a09f49e
commit 3720304984
2 changed files with 127 additions and 1 deletions

View File

@ -0,0 +1,119 @@
From ecaaf4456e5aeacae1acdb1775bb5aadd3b19e13 Mon Sep 17 00:00:00 2001
From: Iker Pedrosa <ipedrosa@redhat.com>
Date: Wed, 16 Oct 2024 12:41:09 +0200
Subject: [PATCH 1/2] pam_access: always match local address
* modules/pam_access/pam_access.c: match the local address regardless of
the IP version in use.
In some circumstances the `localhost` may be translated to IPv4 or IPv6,
but the configuration file only indicated the address for one of the two
versions. Since the originating value is set in `PAM_RHOST` and PAM has
no control over it, let's match the local addresses regardless of the IP
version in use.
Resolves: https://issues.redhat.com/browse/RHEL-23018
Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
---
modules/pam_access/pam_access.c | 30 ++++++++++++++++++++++++++++--
1 file changed, 28 insertions(+), 2 deletions(-)
diff --git a/modules/pam_access/pam_access.c b/modules/pam_access/pam_access.c
index bfbc6d57..48e7c7e9 100644
--- a/modules/pam_access/pam_access.c
+++ b/modules/pam_access/pam_access.c
@@ -306,6 +306,23 @@ isipaddr (const char *string, int *addr_type,
return is_ip;
}
+/* is_local_addr - checks if the IP address is local */
+static int
+is_local_addr (const char *string, int addr_type)
+{
+ if (addr_type == AF_INET) {
+ if (strcmp(string, "127.0.0.1") == 0) {
+ return YES;
+ }
+ } else if (addr_type == AF_INET6) {
+ if (strcmp(string, "::1") == 0) {
+ return YES;
+ }
+ }
+
+ return NO;
+}
+
/* are_addresses_equal - translate IP address strings to real IP
* addresses and compare them to find out if they are equal.
@@ -327,9 +344,18 @@ are_addresses_equal (const char *ipaddr0, const char *ipaddr1,
if (isipaddr (ipaddr1, &addr_type1, &addr1) == NO)
return NO;
- if (addr_type0 != addr_type1)
- /* different address types */
+ if (addr_type0 != addr_type1) {
+ /* different address types, but there is still a possibility that they are
+ * both local addresses
+ */
+ int local1 = is_local_addr(ipaddr0, addr_type0);
+ int local2 = is_local_addr(ipaddr1, addr_type1);
+
+ if (local1 == YES && local2 == YES)
+ return YES;
+
return NO;
+ }
if (netmask != NULL) {
/* Got a netmask, so normalize addresses? */
--
2.47.0
From 641dfd1084508c63f3590e93a35b80ffc50774e5 Mon Sep 17 00:00:00 2001
From: Iker Pedrosa <ipedrosa@redhat.com>
Date: Fri, 18 Oct 2024 10:27:07 +0200
Subject: [PATCH 2/2] pam_access: clarify `LOCAL` keyword behaviour
* modules/pam_access/access.conf.5.xml: `LOCAL` keyword behaviour
explanation was focused on the development internals. Let's clarify it
by rephrasing it to something a sysadmin can understand.
Resolves: https://issues.redhat.com/browse/RHEL-39943
Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
---
modules/pam_access/access.conf.5.xml | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)
diff --git a/modules/pam_access/access.conf.5.xml b/modules/pam_access/access.conf.5.xml
index 35a1a8fe..0b93db00 100644
--- a/modules/pam_access/access.conf.5.xml
+++ b/modules/pam_access/access.conf.5.xml
@@ -79,17 +79,12 @@
with network mask (where network mask can be a decimal number or an
internet address also), <emphasis>ALL</emphasis> (which always matches)
or <emphasis>LOCAL</emphasis>. The <emphasis>LOCAL</emphasis>
- keyword matches if and only if
- <citerefentry><refentrytitle>pam_get_item</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- when called with an <parameter>item_type</parameter> of
- <emphasis>PAM_RHOST</emphasis>, returns <code>NULL</code> or an
- empty string (and therefore the
- <replaceable>origins</replaceable> field is compared against the
- return value of
- <citerefentry><refentrytitle>pam_get_item</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- called with an <parameter>item_type</parameter> of
- <emphasis>PAM_TTY</emphasis> or, absent that,
- <emphasis>PAM_SERVICE</emphasis>).
+ keyword matches when the user connects without a network
+ connection (e.g., <emphasis>su</emphasis>,
+ <emphasis>login</emphasis>). A connection through the loopback
+ device (e.g., <command>ssh user@localhost</command>) is
+ considered a network connection, and thus, the
+ <emphasis>LOCAL</emphasis> keyword does not match.
</para>
<para>
--
2.47.0

View File

@ -4,7 +4,7 @@
Summary: An extensible library which provides authentication for applications
Name: pam
Version: 1.6.1
Release: 5%{?dist}
Release: 6%{?dist}
# The library is BSD licensed with option to relicense as GPLv2+
# - this option is redundant as the BSD license allows that anyway.
# pam_timestamp and pam_loginuid modules are GPLv2+.
@ -29,6 +29,8 @@ Patch3: pam-1.5.3-unix-nomsg.patch
Patch4: pam-1.6.1-sast-fixes.patch
# https://github.com/linux-pam/linux-pam/commit/aabd5314a6d76968c377969b49118a2df3f97003
Patch5: pam-1.6.1-pam-env-econf-read-file-fixes.patch
# https://github.com/linux-pam/linux-pam/commit/641dfd1084508c63f3590e93a35b80ffc50774e5
Patch6: pam-1.6.1-pam-access-local.patch
%{load:%{SOURCE3}}
@ -124,6 +126,7 @@ cp %{SOURCE18} .
%patch -P 3 -p1 -b .nomsg
%patch -P 4 -p1 -b .sast-fixes
%patch -P 5 -p1 -b .pam-env-econf-read-file-fixes
%patch -P 6 -p1 -b .pam-access-local
autoreconf -i
@ -362,6 +365,10 @@ done
%{_pam_libdir}/libpam_misc.so.%{so_ver}*
%changelog
* Mon Nov 4 2024 Iker Pedrosa <ipedrosa@redhat.com> - 1.6.1-6
- pam_access: always match local address and clarify LOCAL keyword behaviour.
Resolves: RHEL-65223
* Tue Oct 29 2024 Troy Dawson <tdawson@redhat.com>
- Bump release for October 2024 mass rebuild:
Resolves: RHEL-64018