IMP(13.13): Add exceptions for home directories not owned by owner

Fill tests

Apply shellcheck recommendations

bin/hardening/13.13_check_user_homedir_ownership.sh

@@ -1,5 +1,6 @@
 #!/bin/bash
 
+# run-shellcheck
 #
 # CIS Debian Hardening
 #
@@ -11,26 +12,33 @@
 set -e # One error, it's over
 set -u # One variable unset, it's over
 
+# shellcheck disable=2034
 HARDENING_LEVEL=2
+# shellcheck disable=2034
 DESCRIPTION="Check user home directory ownership."
+EXCEPTIONS=""
 
 ERRORS=0
 
 # This function will be called if the script status is on enabled / audit mode
 audit () {
-    RESULT=$(cat /etc/passwd | awk -F: '{ print $1 ":" $3 ":" $6 }')
+    RESULT=$(awk -F: '{ print $1 ":" $3 ":" $6 }' /etc/passwd )
     for LINE in $RESULT; do
         debug "Working on $LINE"
-        USER=$(awk -F: {'print $1'} <<< $LINE)
-        USERID=$(awk -F: {'print $2'} <<< $LINE)
-        DIR=$(awk -F: {'print $3'} <<< $LINE)    
-        if [ $USERID -ge 500 -a -d "$DIR" -a $USER != "nfsnobody" ]; then
+        USER=$(awk -F: '{print $1}' <<< "$LINE")
+        USERID=$(awk -F: '{print $2}' <<< "$LINE")
+        DIR=$(awk -F: '{print $3}' <<< "$LINE")
+        if [ "$USERID" -ge 500 ] && [ -d "$DIR" ] && [ "$USER" != "nfsnobody" ]; then
             OWNER=$(stat -L -c "%U" "$DIR")
             if [ "$OWNER" != "$USER" ]; then
+                if grep -qw "$DIR:$USER:$OWNER" <<< "$EXCEPTIONS"; then
+                    ok "The home directory ($DIR) of user $USER is owned by $OWNER but is part of exceptions ($DIR:$USER:$OWNER)."
+                else
                     crit "The home directory ($DIR) of user $USER is owned by $OWNER."
                     ERRORS=$((ERRORS+1))
                 fi
             fi
+        fi
     done
 
     if [ $ERRORS = 0 ]; then
@@ -40,17 +48,26 @@ audit () {
 
 # This function will be called if the script status is on enabled mode
 apply () {
-    cat /etc/passwd | awk -F: '{ print $1 " " $3 " " $6 }' | while read USER USERID DIR; do
-        if [ $USERID -ge 500 -a -d "$DIR" -a $USER != "nfsnobody" ]; then
+    awk -F: '{ print $1 " " $3 " " $6 }'  /etc/passwd | while read -r USER USERID DIR; do
+        if [ "$USERID" -ge 500 ] && [ -d "$DIR" ] && [ "$USER" != "nfsnobody" ]; then
             OWNER=$(stat -L -c "%U" "$DIR")
             if [ "$OWNER" != "$USER" ]; then
                 warn "The home directory ($DIR) of user $USER is owned by $OWNER."
-                chown $USER $DIR
+                chown "$USER" "$DIR"
             fi
         fi
     done
 }
 
+# This function will create the config file for this check with default values
+create_config() {
+    cat <<EOF
+status=audit
+# Specify here exception for which owner of user's home directory is not the user
+# "home:user:owner home2:user2:owner2"
+EXCEPTIONS=""
+EOF
+}
 # This function will check config parameters required
 check_config() {
     :
@@ -67,8 +84,9 @@ if [ -z "$CIS_ROOT_DIR" ]; then
 fi
 
 # Main function, will call the proper functions given the configuration (audit, enabled, disabled)
-if [ -r $CIS_ROOT_DIR/lib/main.sh ]; then
-    . $CIS_ROOT_DIR/lib/main.sh
+if [ -r "$CIS_ROOT_DIR"/lib/main.sh ]; then
+    # shellcheck source=/opt/debian-cis/lib/main.sh
+    . "$CIS_ROOT_DIR"/lib/main.sh
 else
     echo "Cannot find main.sh, have you correctly defined your root directory? Current value is $CIS_ROOT_DIR in /etc/default/cis-hardening"
     exit 128

tests/hardening/13.13_check_user_homedir_ownership.sh

@@ -2,9 +2,23 @@
 test_audit() {
     describe Running on blank host
     register_test retvalshouldbe 0
-    dismiss_count_for_test
     # shellcheck disable=2154
     run blank /opt/debian-cis/bin/hardening/"${script}".sh --audit-all
 
-    # TODO fill comprehensive tests
+    useradd -m testhomeuser
+    chown root:root /home/testhomeuser
+
+    describe Wrong home owner
+    register_test retvalshouldbe 1
+    run wronghomeowner /opt/debian-cis/bin/hardening/"${script}".sh --audit-all
+
+    echo "EXCEPTIONS=\"/home/testhomeuser:testhomeuser:root\"" >> /opt/debian-cis/etc/conf.d/"${script}".cfg
+    sed -i 's/audit/enabled/' /opt/debian-cis/etc/conf.d/"${script}".cfg
+
+    describe Added exceptions
+    register_test retvalshouldbe 0
+    run exceptions /opt/debian-cis/bin/hardening/"${script}".sh --audit-all
+
+    # Cleanup
+    userdel testhomeuser
 }