Overhaul of K3s scans (#1659)

* Overhaul K3s 1.X checks Signed-off-by: Derek Nola <[email protected]> * Overhaul K3s 2.X Checks Signed-off-by: Derek Nola <[email protected]> * Overhaul K3s 4.X checks Signed-off-by: Derek Nola <[email protected]> * Overhaul K3s 5.X checks Signed-off-by: Derek Nola <[email protected]> * Add K3s cis-1.8 scan Signed-off-by: Derek Nola <[email protected]> * Fix K3s 1.1.10 check Signed-off-by: Derek Nola <[email protected]> * Merge journalctl checks for K3s Signed-off-by: Derek Nola <[email protected]> * Matched Manual/Automated to correct scoring (false/true) Signed-off-by: Derek Nola <[email protected]> * Remove incorrect use of check_for_default_sa.sh script Signed-off-by: Derek Nola <[email protected]> --------- Signed-off-by: Derek Nola <[email protected]> Co-authored-by: afdesk <[email protected]>
aquasecurity · Sep 25, 2024 · a9422a6 · a9422a6
1 parent f8b6f2f
commit a9422a6
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diff --git a/cfg/config.yaml b/cfg/config.yaml
@@ -164,7 +164,6 @@ node:
       - "/var/snap/microk8s/current/credentials/kubelet.config"
       - "/etc/kubernetes/kubeconfig-kubelet"
       - "/var/lib/rancher/rke2/agent/kubelet.kubeconfig"
-      - "/var/lib/rancher/k3s/server/cred/admin.kubeconfig"
       - "/var/lib/rancher/k3s/agent/kubelet.kubeconfig"
     confs:
       - "/etc/kubernetes/kubelet-config.yaml"
@@ -190,7 +189,6 @@ node:
       - "/etc/systemd/system/snap.kubelet.daemon.service"
       - "/etc/systemd/system/snap.microk8s.daemon-kubelet.service"
       - "/etc/kubernetes/kubelet.yaml"
-      - "/var/lib/rancher/rke2/agent/kubelet.kubeconfig"
 
     defaultconf: "/var/lib/kubelet/config.yaml"
     defaultsvc: "/etc/systemd/system/kubelet.service.d/10-kubeadm.conf"
@@ -438,6 +436,12 @@ target_mapping:
     - "controlplane"
     - "node"
     - "policies"
+  "k3s-cis-1.8":
+    - "master"
+    - "etcd"
+    - "controlplane"
+    - "node"
+    - "policies"
   "k3s-cis-1.23":
     - "master"
     - "etcd"

diff --git a/cfg/k3s-cis-1.23/controlplane.yaml b/cfg/k3s-cis-1.23/controlplane.yaml
@@ -21,7 +21,7 @@ groups:
     checks:
       - id: 3.2.1
         text: "Ensure that a minimal audit policy is created (Manual)"
-        audit: "journalctl -D /var/log/journal  -u k3s | grep 'Running kube-apiserver' | tail -n1 | grep 'audit-policy-file'"
+        audit: "journalctl -m -u k3s | grep 'Running kube-apiserver' | tail -n1 | grep 'audit-policy-file'"
         type: "manual"
         tests:
           test_items:

diff --git a/cfg/k3s-cis-1.23/master.yaml b/cfg/k3s-cis-1.23/master.yaml
diff --git a/cfg/k3s-cis-1.23/node.yaml b/cfg/k3s-cis-1.23/node.yaml
@@ -186,7 +186,7 @@ groups:
     checks:
       - id: 4.2.1
         text: "Ensure that the --anonymous-auth argument is set to false (Automated)"
-        audit: '/bin/sh -c ''if test $(journalctl -D /var/log/journal -u k3s | grep "Running kube-apiserver" | wc -l) -gt 0; then journalctl -D /var/log/journal -u k3s | grep "Running kube-apiserver" | tail -n1 | grep "anonymous-auth" | grep -v grep; else echo "--anonymous-auth=false"; fi'' '
+        audit: '/bin/sh -c ''if test $(journalctl -m -u k3s | grep "Running kube-apiserver" | wc -l) -gt 0; then journalctl -m -u k3s | grep "Running kube-apiserver" | tail -n1 | grep "anonymous-auth" | grep -v grep; else echo "--anonymous-auth=false"; fi'' '
         tests:
           test_items:
             - flag: "--anonymous-auth"
@@ -209,7 +209,7 @@ groups:
 
       - id: 4.2.2
         text: "Ensure that the --authorization-mode argument is not set to AlwaysAllow (Automated)"
-        audit: '/bin/sh -c ''if test $(journalctl -D /var/log/journal -u k3s | grep "Running kube-apiserver" | wc -l) -gt 0; then journalctl -D /var/log/journal -u k3s | grep "Running kube-apiserver" | tail -n1 | grep "authorization-mode" | grep -v grep; else echo "--authorization-mode=Webhook"; fi'' '
+        audit: '/bin/sh -c ''if test $(journalctl -m -u k3s | grep "Running kube-apiserver" | wc -l) -gt 0; then journalctl -m -u k3s | grep "Running kube-apiserver" | tail -n1 | grep "authorization-mode" | grep -v grep; else echo "--authorization-mode=Webhook"; fi'' '
         tests:
           test_items:
             - flag: --authorization-mode
@@ -231,7 +231,7 @@ groups:
 
       - id: 4.2.3
         text: "Ensure that the --client-ca-file argument is set as appropriate (Automated)"
-        audit: '/bin/sh -c ''if test $(journalctl -D /var/log/journal -u k3s | grep "Running kube-apiserver" | wc -l) -gt 0; then journalctl -D /var/log/journal -u k3s | grep "Running kube-apiserver" | tail -n1 | grep "client-ca-file" | grep -v grep; else echo "--client-ca-file=/var/lib/rancher/k3s/server/tls/request-header-ca.crt"; fi'' '
+        audit: '/bin/sh -c ''if test $(journalctl -m -u k3s | grep "Running kube-apiserver" | wc -l) -gt 0; then journalctl -m -u k3s | grep "Running kube-apiserver" | tail -n1 | grep "client-ca-file" | grep -v grep; else echo "--client-ca-file=/var/lib/rancher/k3s/server/tls/request-header-ca.crt"; fi'' '
         tests:
           test_items:
             - flag: --client-ca-file
@@ -251,7 +251,7 @@ groups:
 
       - id: 4.2.4
         text: "Ensure that the --read-only-port argument is set to 0 (Manual)"
-        audit: "journalctl -D /var/log/journal -u k3s | grep 'Running kubelet' | tail -n1 | grep 'read-only-port' "
+        audit: "journalctl -m -u k3s | grep 'Running kubelet' | tail -n1 | grep 'read-only-port' "
         tests:
           bin_op: or
           test_items:
@@ -276,7 +276,7 @@ groups:
 
       - id: 4.2.5
         text: "Ensure that the --streaming-connection-idle-timeout argument is not set to 0 (Manual)"
-        audit: "journalctl -D /var/log/journal -u k3s | grep 'Running kubelet' | tail -n1 | grep 'streaming-connection-idle-timeout'"
+        audit: "journalctl -m -u k3s | grep 'Running kubelet' | tail -n1 | grep 'streaming-connection-idle-timeout'"
         tests:
           test_items:
             - flag: --streaming-connection-idle-timeout
@@ -302,7 +302,7 @@ groups:
 
       - id: 4.2.6
         text: "Ensure that the --protect-kernel-defaults argument is set to true (Automated)"
-        audit: "journalctl -D /var/log/journal -u k3s | grep 'Running kubelet' | tail -n1 | grep 'protect-kernel-defaults'"
+        audit: "journalctl -m -u k3s | grep 'Running kubelet' | tail -n1 | grep 'protect-kernel-defaults'"
         type: "skip"
         tests:
           test_items:
@@ -325,7 +325,7 @@ groups:
 
       - id: 4.2.7
         text: "Ensure that the --make-iptables-util-chains argument is set to true (Automated)"
-        audit: "journalctl -D /var/log/journal -u k3s | grep 'Running kubelet' | tail -n1 | grep 'make-iptables-util-chains'"
+        audit: "journalctl -m -u k3s | grep 'Running kubelet' | tail -n1 | grep 'make-iptables-util-chains'"
         type: "skip"
         tests:
           test_items:
@@ -393,7 +393,7 @@ groups:
 
       - id: 4.2.10
         text: "Ensure that the --tls-cert-file and --tls-private-key-file arguments are set as appropriate (Manual)"
-        audit: "journalctl -D /var/log/journal -u k3s | grep 'Running kubelet' | tail -n1"
+        audit: "journalctl -m -u k3s | grep 'Running kubelet' | tail -n1"
         tests:
           test_items:
             - flag: --tls-cert-file

diff --git a/cfg/k3s-cis-1.24/config.yaml b/cfg/k3s-cis-1.24/config.yaml
@@ -16,33 +16,43 @@ master:
   scheduler:
     bins:
       - containerd
+    kubeconfig:
+      - /var/lib/rancher/k3s/server/cred/scheduler.kubeconfig
 
   controllermanager:
     bins:
       - containerd
+    kubeconfig:
+      - /var/lib/rancher/k3s/server/cred/controller.kubeconfig
+
 
   etcd:
     bins:
       - containerd
-    datadirs:
-      - /var/lib/rancher/k3s/server/db/etcd
-
-  node:
-    components:
-      - kubelet
-      - proxy
-
-    kubelet:
-      bins:
-        - containerd
-      defaultkubeconfig: /var/lib/rancher/k3s/agent/kubelet.kubeconfig
-      defaultcafile: /var/lib/rancher/k3s/agent/client-ca.crt
-
-    proxy:
-      bins:
-        - containerd
-      defaultkubeconfig: /var/lib/rancher/k3s/agent/kubeproxy.kubeconfig
-
-  policies:
-    components:
-      - policies
+
+etcd:
+  components:
+    - etcd
+
+  etcd:
+    confs: /var/lib/rancher/k3s/server/db/etcd/config
+
+node:
+  components:
+    - kubelet
+    - proxy
+
+  kubelet:
+    bins:
+      - containerd
+    defaultkubeconfig: /var/lib/rancher/k3s/agent/kubelet.kubeconfig
+    defaultcafile: /var/lib/rancher/k3s/agent/client-ca.crt
+
+  proxy:
+    bins:
+      - containerd
+    defaultkubeconfig: /var/lib/rancher/k3s/agent/kubeproxy.kubeconfig
+
+policies:
+  components:
+    - policies
diff --git a/cfg/k3s-cis-1.24/controlplane.yaml b/cfg/k3s-cis-1.24/controlplane.yaml
@@ -21,7 +21,7 @@ groups:
     checks:
       - id: 3.2.1
         text: "Ensure that a minimal audit policy is created (Automated)"
-        audit: "journalctl -D /var/log/journal  -u k3s | grep 'Running kube-apiserver' | tail -n1 | grep 'audit-policy-file'"
+        audit: "journalctl -m -u k3s | grep 'Running kube-apiserver' | tail -n1 | grep 'audit-policy-file'"
         tests:
           test_items:
             - flag: "--audit-policy-file"

diff --git a/cfg/k3s-cis-1.24/etcd.yaml b/cfg/k3s-cis-1.24/etcd.yaml
@@ -10,128 +10,135 @@ groups:
     checks:
       - id: 2.1
         text: "Ensure that the --cert-file and --key-file arguments are set as appropriate (Automated)"
-        audit: "grep -A 4 'client-transport-security' $etcdconf | grep -E 'cert-file|key-file'"
+        audit_config: "cat $etcdconf"
         tests:
           bin_op: and
           test_items:
-            - flag: "cert-file"
-              set: true
-            - flag: "key-file"
-              set: true
+            - path: "{.client-transport-security.cert-file}"
+              compare:
+                op: eq
+                value: "/var/lib/rancher/k3s/server/tls/etcd/server-client.crt"
+            - path: "{.client-transport-security.key-file}"
+              compare:
+                op: eq
+                value: "/var/lib/rancher/k3s/server/tls/etcd/server-client.key"
         remediation: |
-          Follow the etcd service documentation and configure TLS encryption.
-          Then, edit the etcd pod specification file /etc/kubernetes/manifests/etcd.yaml
-          on the master node and set the below parameters.
-          --cert-file=</path/to/ca-file>
-          --key-file=</path/to/key-file>
-        scored: true
+          If running on with sqlite or a external DB, etcd checks are Not Applicable.
+          When running with embedded-etcd, K3s generates cert and key files for etcd.
+          These are located in /var/lib/rancher/k3s/server/tls/etcd/.
+          If this check fails, ensure that the configuration file $etcdconf
+          has not been modified to use custom cert and key files.
+        scored: false
 
       - id: 2.2
         text: "Ensure that the --client-cert-auth argument is set to true (Automated)"
-        audit: "grep -A 4 'client-transport-security' $etcdconf | grep 'client-cert-auth'"
+        audit_config: "cat $etcdconf"
         tests:
-          bin_op: or
           test_items:
-            - flag: "--client-cert-auth"
-              set: true
-            - flag: "client-cert-auth"
+            - path: "{.client-transport-security.client-cert-auth}"
               compare:
                 op: eq
                 value: true
-              set: true
         remediation: |
-          Edit the etcd pod specification file $etcdconf on the master
-          node and set the below parameter.
-          --client-cert-auth="true"
-        scored: true
+          If running on with sqlite or a external DB, etcd checks are Not Applicable.
+          When running with embedded-etcd, K3s sets the --client-cert-auth parameter to true.
+          If this check fails, ensure that the configuration file $etcdconf
+          has not been modified to disable client certificate authentication.
+        scored: false
 
       - id: 2.3
         text: "Ensure that the --auto-tls argument is not set to true (Automated)"
-        audit: "if grep -q '^auto-tls' $etcdconf;then grep '^auto-tls' $etcdconf;else echo 'notset';fi"
+        audit_config: "cat $etcdconf"
         tests:
           bin_op: or
           test_items:
-            - flag: "--auto-tls"
-              set: false
-            - flag: "--auto-tls"
+            - path: "{.client-transport-security.auto-tls}"
               compare:
                 op: eq
                 value: false
+            - path: "{.client-transport-security.auto-tls}"
+              set: false
         remediation: |
-          Edit the etcd pod specification file $etcdconf on the master
+          If running on with sqlite or a external DB, etcd checks are Not Applicable.
+          When running with embedded-etcd, K3s does not set the --auto-tls parameter.
+          If this check fails, edit the etcd pod specification file $etcdconf on the master
           node and either remove the --auto-tls parameter or set it to false.
-            --auto-tls=false
-        scored: true
+          client-transport-security:
+            auto-tls: false
+        scored: false
 
       - id: 2.4
         text: "Ensure that the --peer-cert-file and --peer-key-file arguments are set as appropriate (Automated)"
-        audit: "grep -A 4 'peer-transport-security' $etcdconf | grep -E 'cert-file|key-file'"
+        audit_config: "cat $etcdconf"
         tests:
           bin_op: and
           test_items:
-            - flag: "cert-file"
-              set: true
-            - flag: "key-file"
-              set: true
+            - path: "{.peer-transport-security.cert-file}"
+              compare:
+                op: eq
+                value: "/var/lib/rancher/k3s/server/tls/etcd/peer-server-client.crt"
+            - path: "{.peer-transport-security.key-file}"
+              compare:
+                op: eq
+                value: "/var/lib/rancher/k3s/server/tls/etcd/peer-server-client.key"
         remediation: |
-          Follow the etcd service documentation and configure peer TLS encryption as appropriate
-          for your etcd cluster.
-          Then, edit the etcd pod specification file $etcdconf on the
-          master node and set the below parameters.
-          --peer-client-file=</path/to/peer-cert-file>
-          --peer-key-file=</path/to/peer-key-file>
-        scored: true
+          If running on with sqlite or a external DB, etcd checks are Not Applicable.
+          When running with embedded-etcd, K3s generates peer cert and key files for etcd.
+          These are located in /var/lib/rancher/k3s/server/tls/etcd/.
+          If this check fails, ensure that the configuration file $etcdconf
+          has not been modified to use custom peer cert and key files.
+        scored: false
 
       - id: 2.5
         text: "Ensure that the --peer-client-cert-auth argument is set to true (Automated)"
-        audit: "grep -A 4 'peer-transport-security' $etcdconf | grep 'client-cert-auth'"
+        audit_config: "cat $etcdconf"
         tests:
-          bin_op: or
           test_items:
-            - flag: "--client-cert-auth"
-              set: true
-            - flag: "client-cert-auth"
+            - path: "{.peer-transport-security.client-cert-auth}"
               compare:
                 op: eq
                 value: true
-              set: true
         remediation: |
-          Edit the etcd pod specification file $etcdconf on the master
-          node and set the below parameter.
-          --peer-client-cert-auth=true
-        scored: true
+          If running on with sqlite or a external DB, etcd checks are Not Applicable.
+          When running with embedded-etcd, K3s sets the --peer-cert-auth parameter to true.
+          If this check fails, ensure that the configuration file $etcdconf
+          has not been modified to disable peer client certificate authentication.
+        scored: false
 
       - id: 2.6
         text: "Ensure that the --peer-auto-tls argument is not set to true (Automated)"
-        audit: "if grep -q '^peer-auto-tls' $etcdconf;then grep '^peer-auto-tls' $etcdconf;else echo 'notset';fi"
+        audit_config: "cat $etcdconf"
         tests:
           bin_op: or
           test_items:
-            - flag: "--peer-auto-tls"
-              set: false
-            - flag: "--peer-auto-tls"
+            - path: "{.peer-transport-security.auto-tls}"
               compare:
                 op: eq
                 value: false
-              set: true
+            - path: "{.peer-transport-security.auto-tls}"
+              set: false
         remediation: |
-          Edit the etcd pod specification file $etcdconf on the master
+          If running on with sqlite or a external DB, etcd checks are Not Applicable.
+          When running with embedded-etcd, K3s does not set the --peer-auto-tls parameter.
+          If this check fails, edit the etcd pod specification file $etcdconf on the master
           node and either remove the --peer-auto-tls parameter or set it to false.
-          --peer-auto-tls=false
-        scored: true
+          peer-transport-security:
+            auto-tls: false
+        scored: false
 
       - id: 2.7
         text: "Ensure that a unique Certificate Authority is used for etcd (Automated)"
-        audit: "if grep -q 'trusted-ca-file' $etcdconf;then grep 'trusted-ca-file' $etcdconf;else echo 'notset';fi"
+        audit_config: "cat $etcdconf"
         tests:
           test_items:
-            - flag: "trusted-ca-file"
-              set: true
+            - path: "{.peer-transport-security.trusted-ca-file}"
+              compare:
+                op: eq
+                value: "/var/lib/rancher/k3s/server/tls/etcd/peer-ca.crt"
         remediation: |
-          [Manual test]
-          Follow the etcd documentation and create a dedicated certificate authority setup for the
-          etcd service.
-          Then, edit the etcd pod specification file $etcdconf on the
-          master node and set the below parameter.
-          --trusted-ca-file=</path/to/ca-file>
+          If running on with sqlite or a external DB, etcd checks are Not Applicable.
+          When running with embedded-etcd, K3s generates a unique certificate authority for etcd.
+          This is located at /var/lib/rancher/k3s/server/tls/etcd/peer-ca.crt.
+          If this check fails, ensure that the configuration file $etcdconf
+          has not been modified to use a shared certificate authority.
         scored: false