From 829ee8631ff31248632ca192a122f54dfde6068b Mon Sep 17 00:00:00 2001
From: Thibault Ayanides <thibault.ayanides@ovhcloud.com>
Date: Mon, 16 Nov 2020 14:06:39 +0100
Subject: [PATCH] Revert to previous check (8.2.4 in old num)

---
 .../4.2.2.3_syslog_ng_logfiles_perm.sh        | 135 ++++++++++++++----
 1 file changed, 107 insertions(+), 28 deletions(-)

diff --git a/bin/hardening/4.2.2.3_syslog_ng_logfiles_perm.sh b/bin/hardening/4.2.2.3_syslog_ng_logfiles_perm.sh
index 05eb25d..df50474 100755
--- a/bin/hardening/4.2.2.3_syslog_ng_logfiles_perm.sh
+++ b/bin/hardening/4.2.2.3_syslog_ng_logfiles_perm.sh
@@ -5,50 +5,113 @@
 #
 
 #
-# 4.2.2.3 Ensure syslog-ng default file permissions configured (Scored)
+# 4.2.2.3 Create and Set Permissions on syslog-ng Log Files (Scored)
 #
 
 set -e # One error, it's over
 set -u # One variable unset, it's over
 
-HARDENING_LEVEL=3
-DESCRIPTION="Ensure logfile are created with root:640"
+# Note: this is not exacly the same check as the one described in CIS PDF
 
-PATTERN='options[[:space:]]*{[[:alnum:] ()_;"\t]*perm\(0640\);'
+# shellcheck disable=2034
+HARDENING_LEVEL=3
+# shellcheck disable=2034
+DESCRIPTION="Create and set permissions on syslog-ng logfiles."
+
+PERMISSIONS=''
+USER=''
+GROUP=''
+EXCEPTIONS=''
 
 # This function will be called if the script status is on enabled / audit mode
 audit () {
-    FOUND=0
-    FILES="$SYSLOG_BASEDIR/syslog-ng.conf $($SUDO_CMD find -L $SYSLOG_BASEDIR/conf.d/ -type f)"
+    FILES=$(grep "file(" "$SYSLOG_BASEDIR"/syslog-ng.conf | grep '"' | cut -d'"' -f 2)
     for FILE in $FILES; do
-       does_pattern_exist_in_file_multiline "$FILE" "$PATTERN"
-        if [ $FNRET = 0 ]; then
-            FOUND=1
+        does_file_exist "$FILE"
+        if [ "$FNRET" != 0 ]; then
+            warn "$FILE does not exist"
+        else
+            FOUND_EXC=0
+            if grep -q "$FILE" <(tr ' ' '\n' <<< "$EXCEPTIONS" | cut -d ":" -f 1); then
+                debug "$FILE is found in exceptions"
+                debug "Setting special user:group:perm"
+                FOUND_EXC=1
+                local user_bak="$USER"
+                local group_bak="$GROUP"
+                local perm_bak="$PERMISSIONS"
+                USER="$(tr ' ' '\n' <<< "$EXCEPTIONS" | grep "$FILE" | cut -d':' -f 2)"
+                GROUP="$(tr ' ' '\n' <<< "$EXCEPTIONS" | grep "$FILE" | cut -d':' -f 3)"
+                PERMISSIONS="$(tr ' ' '\n' <<< "$EXCEPTIONS" | grep "$FILE" | cut -d':' -f 4)"
+            fi
+            has_file_correct_ownership "$FILE" "$USER" "$GROUP"
+            if [ "$FNRET" = 0 ]; then
+                ok "$FILE has correct ownership ($USER:$GROUP)"
+            else
+                crit "$FILE ownership was not set to $USER:$GROUP"
+            fi
+            has_file_correct_permissions "$FILE" "$PERMISSIONS"
+            if [ "$FNRET" = 0 ]; then
+                ok "$FILE has correct permissions ($PERMISSIONS)"
+            else
+                crit "$FILE permissions were not set to $PERMISSIONS"
+            fi
+            if [ "$FOUND_EXC" = 1 ]; then
+                debug "Resetting user:group:perm"
+                USER="$user_bak"
+                GROUP="$group_bak"
+                PERMISSIONS="$perm_bak"
+            fi
         fi
     done
-
-    if [ $FOUND = 1 ]; then
-        ok "$PATTERN is present in $FILES"
-    else
-        crit "$PATTERN is not present in $FILES"
-    fi
 }
 
 # This function will be called if the script status is on enabled mode
 apply () {
-    FOUND=0
-    FILES="$SYSLOG_BASEDIR/syslog-ng.conf $(find -L $SYSLOG_BASEDIR/conf.d/ -type f)"
     for FILE in $FILES; do
-       does_pattern_exist_in_file_multiline "$FILE" "$PATTERN"
-        if [ $FNRET = 0 ]; then
-            FOUND=1
+        does_file_exist "$FILE"
+        if [ "$FNRET" != 0 ]; then
+            info "$FILE does not exist"
+            filedir=$(dirname "${FILE#/var/log/}")
+            if [ ! "$filedir" = "." ] && [ ! -d /var/log/"$filedir" ]; then
+                debug "Creating /var/log/$filedir for $FILE"
+                debug "mkdir -p /var/log/$filedir"
+                mkdir -p /var/log/"$filedir"
+            fi
+            touch "$FILE"
+        fi
+        FOUND_EXC=0
+        if grep "$FILE" <(tr ' ' '\n' <<< "$EXCEPTIONS" | cut -d ":" -f 1); then
+            debug "$FILE is found in exceptions"
+            debug "Setting special user:group:perm"
+            FOUND_EXC=1
+            local user_bak="$USER"
+            local group_bak="$GROUP"
+            local perm_bak="$PERMISSIONS"
+            USER="$(tr ' ' '\n' <<< "$EXCEPTIONS" | grep "$FILE" | cut -d':' -f 2)"
+            GROUP="$(tr ' ' '\n' <<< "$EXCEPTIONS" | grep "$FILE" | cut -d':' -f 3)"
+            PERMISSIONS="$(tr ' ' '\n' <<< "$EXCEPTIONS" | grep "$FILE" | cut -d':' -f 4)"
+        fi
+        has_file_correct_ownership "$FILE" "$USER" "$GROUP"
+        if [ "$FNRET" = 0 ]; then
+            ok "$FILE has correct ownership"
+        else
+            warn "fixing $FILE ownership to $USER:$GROUP"
+            chown "$USER":"$GROUP" "$FILE"
+        fi
+        has_file_correct_permissions "$FILE" "$PERMISSIONS"
+        if [ "$FNRET" = 0 ]; then
+            ok "$FILE has correct permissions"
+        else
+            info "fixing $FILE permissions to $PERMISSIONS"
+            chmod 0"$PERMISSIONS" "$FILE"
+        fi
+        if [ "$FOUND_EXC" = 1 ]; then
+            debug "Resetting user:group:perm"
+            USER="$user_bak"
+            GROUP="$group_bak"
+            PERMISSIONS="$perm_bak"
         fi
     done
-    if [ $FOUND = 1 ]; then
-        ok "$PATTERN is present in $FILES"
-    else
-        crit "$PATTERN is not present in $FILES, please set a remote host to send your logs"
-    fi
 }
 
 # This function will create the config file for this check with default values
@@ -56,12 +119,27 @@ create_config() {
     cat <<EOF
 status=audit
 SYSLOG_BASEDIR='/etc/syslog-ng'
+PERMISSIONS='640'
+USER='root'
+GROUP='adm'
+# Put exceptions here with file:user:group:permissions
+# example: /dev/null:root:root:666
+EXCEPTIONS=''
 EOF
 }
 
 # This function will check config parameters required
 check_config() {
-    :
+    does_user_exist "$USER"
+    if [ "$FNRET" != 0 ]; then
+        crit "$USER does not exist"
+        exit 128
+    fi
+    does_group_exist $GROUP
+    if [ "$FNRET" != 0 ]; then
+        crit "$GROUP does not exist"
+        exit 128
+    fi
 }
 
 # Source Root Dir Parameter
@@ -75,8 +153,9 @@ 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