Warn for insecure PEM file encryption

Author: markt-asf

java/org/apache/tomcat/util/net/jsse/LocalStrings.properties

@@ -20,6 +20,8 @@ jsseUtil.excludeProtocol=The SSL protocol [{0}] which is supported in this JRE w
 jsseUtil.noDefaultProtocols=Unable to determine a default for sslEnabledProtocols. Set an explicit value to ensure the connector can start.
 jsseUtil.opensslconf.present=A connector is configured to use a JSSE TLS implementation with OpenSSL specific OpenSSLConf configuration elements. The OpenSSLConf configuration elements will be ignored.
 
+pemFile.encryption.broken=The PEM file [{0}] is using [{1}] which is considered broken because a brute force attack is trivial with current hardware
+pemFile.encryption.insecure=The PEM file [{0}] is using [{1}] which is considered insecure as it is vulnerable to a brute-force attack
 pemFile.noMultiPrimes=The PKCS#1 certificate is in multi-prime format and Java does not provide an API for constructing an RSA private key object from that format
 pemFile.noPassword=A password is required to decrypt the private key
 pemFile.notPbkdf2=The OID [{0}] is not the correct OID for PKBDF2 which is the only permitted KDF for PBES2

java/org/apache/tomcat/util/net/jsse/PEMFile.java

@@ -51,6 +51,8 @@
 import javax.crypto.spec.PBEKeySpec;
 import javax.crypto.spec.SecretKeySpec;
 
+import org.apache.juli.logging.Log;
+import org.apache.juli.logging.LogFactory;
 import org.apache.tomcat.util.buf.Asn1Parser;
 import org.apache.tomcat.util.buf.Asn1Writer;
 import org.apache.tomcat.util.buf.HexUtils;
@@ -64,6 +66,7 @@
  */
 public class PEMFile {
 
+    private static final Log log = LogFactory.getLog(PEMFile.class);
     private static final StringManager sm = StringManager.getManager(PEMFile.class);
 
     private static final byte[] OID_EC_PUBLIC_KEY =
@@ -370,18 +373,21 @@ public PrivateKey toPrivateKey(String password, String keyAlgorithm, Format form
                             secretKeyAlgorithm = "DES";
                             cipherTransformation = "DES/CBC/PKCS5Padding";
                             keyLength = 8;
+                            log.error(sm.getString("pemFile.encryption.broken", filename, algorithm));
                             break;
                         }
                         case "DES-EDE3-CBC": {
                             secretKeyAlgorithm = "DESede";
                             cipherTransformation = "DESede/CBC/PKCS5Padding";
                             keyLength = 24;
+                            log.warn(sm.getString("pemFile.encryption.insecure", filename, algorithm));
                             break;
                         }
                         case "AES-256-CBC": {
                             secretKeyAlgorithm = "AES";
                             cipherTransformation = "AES/CBC/PKCS5Padding";
                             keyLength = 32;
+                            log.warn(sm.getString("pemFile.encryption.insecure", filename, algorithm));
                             break;
                         }
                         default:
@@ -501,6 +507,7 @@ public PrivateKey toPrivateKey(String password, String keyAlgorithm, Format form
                         throw new NoSuchAlgorithmException(
                                 sm.getString("pemFile.unknownEncryptionAlgorithm", toDottedOidString(oidCipher)));
                     }
+                    log.warn(sm.getString("pemFile.encryption.insecure", filename, algorithm));
 
                     byte[] iv = p.parseOctetString();
 

webapps/docs/changelog.xml

@@ -258,6 +258,10 @@
         Remove support for HTTP 0.9. (markt)
       </update>
       <!-- Entries for backport and removal before 12.0.0-M1 below this line -->
+      <add>
+        Log a suitable warning if an encrypted PEM file is detected using an
+        insecure form for encryption. (markt)
+      </add>
     </changelog>
   </subsection>
   <subsection name="Jasper">