fix mesh state permissions for Control

deploy/ochenstarik-server-monitor-manager.sh

@@ -574,6 +574,7 @@ prepare_control_state() {
     chown -R "$CONTROL_USER:$CONTROL_USER" "$STATE_DIR/control"
     find "$STATE_DIR/control" -type d -exec chmod 0700 {} +
     find "$STATE_DIR/control" -type f -exec chmod 0600 {} +
+    repair_mesh_state_permissions
 }
 
 reverse_control_state_migration() {
@@ -682,6 +683,22 @@ read_mesh_value() {
     awk -F '=' -v key="$key" '$1 == key { print substr($0, index($0, "=") + 1); exit }' "$ETC_DIR/mesh.env"
 }
 
+ensure_mesh_state() {
+    install -d -m 0770 -o root -g "$CONTROL_USER" "$MESH_DIR"
+    touch "$MESH_DIR/nodes.tsv"
+    chown root:"$CONTROL_USER" "$MESH_DIR/nodes.tsv"
+    chmod 0660 "$MESH_DIR/nodes.tsv"
+}
+
+repair_mesh_state_permissions() {
+    [[ -d "$MESH_DIR" ]] || return 0
+    install -d -m 0770 -o root -g "$CONTROL_USER" "$MESH_DIR"
+    if [[ -e "$MESH_DIR/nodes.tsv" ]]; then
+        chown root:"$CONTROL_USER" "$MESH_DIR/nodes.tsv"
+        chmod 0660 "$MESH_DIR/nodes.tsv"
+    fi
+}
+
 render_hub_wireguard_config() {
     local private_key endpoint port node_id address public_key status
     private_key="$(cat "$WG_DIR/hub.key")"
@@ -719,8 +736,10 @@ mesh_init() {
     fi
     [[ "$public_endpoint" =~ ^[A-Za-z0-9]([A-Za-z0-9.-]{0,251}[A-Za-z0-9])?$ ]] \
         || fail "Invalid WireGuard public endpoint."
+    ensure_system_user "$CONTROL_USER"
     ensure_mesh_packages
-    install -d -m 0700 "$WG_DIR" "$MESH_DIR" /etc/wireguard
+    install -d -m 0700 -o root -g root "$WG_DIR" /etc/wireguard
+    ensure_mesh_state
     if [[ ! -f "$WG_DIR/hub.key" ]]; then
         umask 077
         wg genkey >"$WG_DIR/hub.key"
@@ -736,8 +755,6 @@ HUB_PUBLIC_KEY=$hub_public
 MESH_NETWORK=$MESH_NETWORK
 EOF
     chmod 0644 "$ETC_DIR/mesh.env"
-    touch "$MESH_DIR/nodes.tsv"
-    chmod 0600 "$MESH_DIR/nodes.tsv"
     printf '%s\n' 'net.ipv4.ip_forward=1' >"/etc/sysctl.d/90-ochenstarik-smm-mesh.conf"
     sysctl --system >/dev/null
     write_mesh_firewall
@@ -761,9 +778,7 @@ EOF
 
 reserve_node_address() {
     local node_id="$1" existing host address
-    install -d -m 0700 "$MESH_DIR"
+    ensure_mesh_state
-    touch "$MESH_DIR/nodes.tsv"
-    chmod 0600 "$MESH_DIR/nodes.tsv"
     existing="$(awk -F '\t' -v node="$node_id" '$1 == node { print $2; exit }' "$MESH_DIR/nodes.tsv")"
     if [[ -n "$existing" ]]; then
         printf '%s\n' "$existing"
@@ -1359,7 +1374,8 @@ add_mesh_peer() {
     awk -F '\t' -v OFS='\t' -v node="$node_id" -v address="$address" -v key="$public_key" \
         '$1 == node { print node, address, key, "active"; found=1; next } { print } END { if (!found) exit 1 }' \
         "$MESH_DIR/nodes.tsv" >"$tmp" || { rm -f -- "$tmp"; fail "Peer reservation is missing."; }
-    chmod 0600 "$tmp"
+    chown root:"$CONTROL_USER" "$tmp"
+    chmod 0660 "$tmp"
     mv -- "$tmp" "$MESH_DIR/nodes.tsv"
     render_hub_wireguard_config
     systemctl restart wg-quick@smm0.service

deploy/ochenstarik-smm-control.service

@@ -23,7 +23,7 @@ LockPersonality=true
 RestrictSUIDSGID=true
 RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
 UMask=0077
-ReadWritePaths=/var/lib/ochenstarik-server-monitor-manager/control
+ReadWritePaths=/var/lib/ochenstarik-server-monitor-manager/control /var/lib/ochenstarik-server-monitor-manager/mesh
 
 [Install]
 WantedBy=multi-user.target

tests/bootstrap/test-bootstrap-contract.sh

@@ -527,7 +527,18 @@ rm -rf "$role_fixture/lib/agent"
 rm -rf -- "$role_fixture"
 
 grep -Fq 'UMask=0077' "$root/deploy/ochenstarik-smm-control.service"
-grep -Fq 'ReadWritePaths=/var/lib/ochenstarik-server-monitor-manager/control' "$root/deploy/ochenstarik-smm-control.service"
+grep -Fq 'ReadWritePaths=/var/lib/ochenstarik-server-monitor-manager/control /var/lib/ochenstarik-server-monitor-manager/mesh' "$root/deploy/ochenstarik-smm-control.service"
+grep -Fq 'install -d -m 0770 -o root -g "$CONTROL_USER" "$MESH_DIR"' "$bootstrap"
+grep -Fq 'chown root:"$CONTROL_USER" "$MESH_DIR/nodes.tsv"' "$bootstrap"
+grep -Fq 'chmod 0660 "$MESH_DIR/nodes.tsv"' "$bootstrap"
+grep -Fq 'install -d -m 0700 -o root -g root "$WG_DIR" /etc/wireguard' "$bootstrap"
+mesh_init_definition="$(extract_bootstrap_function mesh_init)"
+grep -Fq '    ensure_system_user "$CONTROL_USER"' <<<"$mesh_init_definition"
+[[ "$(grep -Fc '    ensure_mesh_state' "$bootstrap")" -eq 2 ]]
+grep -Fq '    repair_mesh_state_permissions' <<<"$prepare_control_state_definition"
+if [[ "$(uname -s)" != MINGW* ]] && command -v sudo >/dev/null 2>&1; then
+    bash "$root/tests/bootstrap/test-mesh-state-permissions.sh"
+fi
 native_smoke="$root/tests/bootstrap/run-native-systemd-smoke.sh"
 grep -Fq 'node_code="$(sudo "$system_bootstrap" node-code smoke-node)"' "$native_smoke"
 grep -Fq 'export SMM_ENROLL_CODE="$node_code"' "$native_smoke"
@@ -870,4 +881,3 @@ grep -Fq 'record_installed_version agent' "$bootstrap" || {
 }
 
 printf '%s\n' "BOOTSTRAP_CONTRACT=PASS"
-

tests/bootstrap/test-mesh-state-permissions.sh

@@ -0,0 +1,61 @@
+#!/usr/bin/env bash
+set -Eeuo pipefail
+IFS=$'\n\t'
+
+root="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/../.." && pwd)"
+bootstrap="$root/deploy/ochenstarik-server-monitor-manager.sh"
+fixture="$(mktemp -d -t smm-mesh-permissions.XXXXXXXX)"
+test_user="$(id -un)"
+test_group="$(id -gn)"
+mesh_dir="$fixture/state/mesh"
+wg_dir="$fixture/etc/wireguard"
+
+cleanup() {
+    sudo rm -rf -- "$fixture"
+}
+trap cleanup EXIT
+
+extract_function() {
+    local name="$1"
+    awk -v name="$name" '
+        $0 == name "() {" { capture=1 }
+        capture { print }
+        capture && $0 == "}" { exit }
+    ' "$bootstrap"
+}
+
+ensure_definition="$(extract_function ensure_mesh_state)"
+repair_definition="$(extract_function repair_mesh_state_permissions)"
+runner="$fixture/apply-permissions.sh"
+{
+    printf '%s\n%s\n' "$ensure_definition" "$repair_definition"
+    printf '%s\n' 'ensure_mesh_state'
+} >"$runner"
+
+sudo env MESH_DIR="$mesh_dir" CONTROL_USER="$test_group" bash "$runner"
+[[ "$(sudo stat -c '%a:%U:%G' "$mesh_dir")" == "770:root:$test_group" ]]
+[[ "$(sudo stat -c '%a:%U:%G' "$mesh_dir/nodes.tsv")" == "660:root:$test_group" ]]
+
+printf '%s\n' $'fixture-node\t10.77.0.2\t-\treserved' >>"$mesh_dir/nodes.tsv"
+grep -Fq 'fixture-node' "$mesh_dir/nodes.tsv"
+
+sudo install -d -m 0700 -o root -g root "$wg_dir"
+printf '%s\n' 'private-hub-key' | sudo tee "$wg_dir/hub.key" >/dev/null
+sudo chown root:root "$wg_dir/hub.key"
+sudo chmod 0600 "$wg_dir/hub.key"
+if sudo -u "$test_user" test -r "$wg_dir/hub.key"; then
+    printf '%s\n' 'Control-equivalent user can read the Hub private key' >&2
+    exit 1
+fi
+
+sudo chmod 0700 "$mesh_dir"
+sudo chmod 0600 "$mesh_dir/nodes.tsv"
+{
+    printf '%s\n%s\n' "$ensure_definition" "$repair_definition"
+    printf '%s\n' 'repair_mesh_state_permissions'
+} >"$runner"
+sudo env MESH_DIR="$mesh_dir" CONTROL_USER="$test_group" bash "$runner"
+[[ "$(sudo stat -c '%a:%U:%G' "$mesh_dir")" == "770:root:$test_group" ]]
+[[ "$(sudo stat -c '%a:%U:%G' "$mesh_dir/nodes.tsv")" == "660:root:$test_group" ]]
+
+printf '%s\n' 'MESH_STATE_PERMISSIONS=PASS'