Fiddling around with MIC calculation

Author: phax

phase2-lib/src/main/java/com/helger/phase2/crypto/BCCryptoHelper.java

@@ -47,7 +47,6 @@
 import java.security.cert.X509Certificate;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.Enumeration;
 import java.util.LinkedHashMap;
 import java.util.Locale;
 import java.util.Map;
@@ -108,7 +107,6 @@
 import com.helger.http.CHttpHeader;
 import com.helger.io.file.FileHelper;
 import com.helger.mail.cte.EContentTransferEncoding;
-import com.helger.phase2.exception.AS2Exception;
 import com.helger.phase2.util.AS2HttpHelper;
 import com.helger.phase2.util.AS2IOHelper;
 import com.helger.phase2.util.AS2ResourceHelper;
@@ -260,13 +258,23 @@ public KeyStore loadKeyStore (@Nonnull final IKeyStoreType aKeyStoreType,
     return aKeyStore;
   }
 
-  public boolean isEncrypted (@Nonnull final MimeBodyPart aPart) throws MessagingException
+  public boolean isEncrypted (@Nonnull final MimeBodyPart aPart)
   {
     ValueEnforcer.notNull (aPart, "Part");
 
+    String sContentType;
+    try
+    {
+      sContentType = aPart.getContentType ();
+    }
+    catch (final MessagingException ex)
+    {
+      sContentType = null;
+    }
+
     // Content-Type is sthg like this if encrypted:
     // application/pkcs7-mime; name=smime.p7m; smime-type=enveloped-data
-    final ContentType aContentType = AS2HttpHelper.parseContentType (aPart.getContentType ());
+    final ContentType aContentType = AS2HttpHelper.parseContentType (sContentType);
     if (aContentType == null)
       return false;
 
@@ -278,19 +286,28 @@ public boolean isEncrypted (@Nonnull final MimeBodyPart aPart) throws MessagingE
     return sSmimeType != null && sSmimeType.equalsIgnoreCase ("enveloped-data");
   }
 
-  public boolean isSigned (@Nonnull final MimeBodyPart aPart) throws MessagingException
+  public boolean isSigned (@Nonnull final MimeBodyPart aPart)
   {
     ValueEnforcer.notNull (aPart, "Part");
 
-    final ContentType aContentType = AS2HttpHelper.parseContentType (aPart.getContentType ());
+    String sContentType;
+    try
+    {
+      sContentType = aPart.getContentType ();
+    }
+    catch (final MessagingException ex)
+    {
+      sContentType = null;
+    }
+    final ContentType aContentType = AS2HttpHelper.parseContentType (sContentType);
     if (aContentType == null)
       return false;
 
     final String sBaseType = aContentType.getBaseType ();
     return sBaseType.equalsIgnoreCase ("multipart/signed");
   }
 
-  public boolean isCompressed (@Nonnull final String sContentType) throws AS2Exception
+  public boolean isCompressed (@Nonnull final String sContentType)
   {
     ValueEnforcer.notNull (sContentType, "ContentType");
 
@@ -332,23 +349,33 @@ public MIC calculateMIC (@Nonnull final MimeBodyPart aPart,
       aMessageDigest = new LoggingMessageDigest (aMessageDigest);
     }
 
+    final int nHeadersIncluded;
+    final StringBuilder aHeadersIncluded = new StringBuilder ();
     if (bIncludeHeaders)
     {
       // Start hashing the header
-      final Enumeration <String> aHeaderLines = aPart.getAllHeaderLines ();
-      while (aHeaderLines.hasMoreElements ())
+      final ICommonsList <String> aHeaderLines = new CommonsArrayList <> (aPart.getAllHeaderLines ());
+      for (final String sHeaderLine : aHeaderLines)
       {
-        final String sHeaderLine = aHeaderLines.nextElement ();
-
         aMessageDigest.update (AS2IOHelper.getAllAsciiBytes (sHeaderLine));
         aMessageDigest.update (EOL_BYTES);
 
         if (LOGGER.isDebugEnabled ())
           LOGGER.debug ("Using header line '" + sHeaderLine + "' for MIC calculation");
+
+        // For debug logging only
+        if (aHeadersIncluded.length () > 0)
+          aHeadersIncluded.append (':');
+        aHeadersIncluded.append (sHeaderLine.substring (0, sHeaderLine.indexOf (':')));
       }
 
       // The CRLF separator between header and content
       aMessageDigest.update (EOL_BYTES);
+      nHeadersIncluded = aHeaderLines.size ();
+    }
+    else
+    {
+      nHeadersIncluded = -1;
     }
 
     final String sMICEncoding = aPart.getEncoding ();
@@ -372,8 +399,14 @@ public MIC calculateMIC (@Nonnull final MimeBodyPart aPart,
     // Perform Base64 encoding and append algorithm ID
     final MIC ret = new MIC (aMIC, eDigestAlgorithm);
 
-    if (LOGGER.isDebugEnabled ())
-      LOGGER.debug ("  Calculated MIC = " + ret.getAsAS2String ());
+    LOGGER.info ("  Calculated MIC[" +
+                 eDigestAlgorithm +
+                 "][" +
+                 nHeadersIncluded +
+                 " headers; " +
+                 aHeadersIncluded.toString () +
+                 "] = " +
+                 ret.getAsAS2String ());
 
     return ret;
   }
@@ -715,11 +748,9 @@ public MimeBodyPart verify (@Nonnull final MimeBodyPart aPart,
     // Get only once and check
     // Throws "ParseException" if it is not a MIME message
     final Object aContent = aPart.getContent ();
-    if (!(aContent instanceof MimeMultipart))
+    if (!(aContent instanceof final MimeMultipart aMainPart))
       throw new IllegalStateException ("Expected Part content to be MimeMultipart but it isn't. It is " +
                                        ClassHelper.getClassName (aContent));
-    final MimeMultipart aMainPart = (MimeMultipart) aContent;
-
     // SMIMESignedParser uses "7bit" as the default - AS2 wants "binary"
     final SMIMESignedParser aSignedParser = new SMIMESignedParser (new JcaDigestCalculatorProviderBuilder ().setProvider (m_sSecurityProviderName)
                                                                                                             .build (),

phase2-lib/src/main/java/com/helger/phase2/crypto/ICryptoHelper.java

@@ -41,7 +41,6 @@
 
 import com.helger.annotation.WillNotClose;
 import com.helger.mail.cte.EContentTransferEncoding;
-import com.helger.phase2.exception.AS2Exception;
 import com.helger.phase2.util.AS2ResourceHelper;
 import com.helger.security.keystore.IKeyStoreType;
 
@@ -92,10 +91,8 @@ KeyStore loadKeyStore (@Nonnull IKeyStoreType aKeyStoreType,
    * @param aPart
    *        The part to be checked.
    * @return <code>true</code> if it is encrypted, <code>false</code> otherwise.
-   * @throws Exception
-   *         In case something goes wrong.
    */
-  boolean isEncrypted (@Nonnull MimeBodyPart aPart) throws Exception;
+  boolean isEncrypted (@Nonnull MimeBodyPart aPart);
 
   /**
    * Check if the passed MIME body part is signed. The default implementation checks if the base
@@ -104,10 +101,8 @@ KeyStore loadKeyStore (@Nonnull IKeyStoreType aKeyStoreType,
    * @param aPart
    *        The part to be checked.
    * @return <code>true</code> if it is signed, <code>false</code> otherwise.
-   * @throws Exception
-   *         In case something goes wrong.
    */
-  boolean isSigned (@Nonnull MimeBodyPart aPart) throws Exception;
+  boolean isSigned (@Nonnull MimeBodyPart aPart);
 
   /**
    * Check if the passed content type indicates compression. The default implementation checks if
@@ -116,10 +111,8 @@ KeyStore loadKeyStore (@Nonnull IKeyStoreType aKeyStoreType,
    * @param sContentType
    *        The content type to be checked. May not be <code>null</code>.
    * @return <code>true</code> if it is compressed, <code>false</code> otherwise.
-   * @throws AS2Exception
-   *         In case something goes wrong.
    */
-  boolean isCompressed (@Nonnull String sContentType) throws AS2Exception;
+  boolean isCompressed (@Nonnull String sContentType);
 
   /**
    * Calculate the MIC

phase2-lib/src/main/java/com/helger/phase2/processor/receiver/net/AS2ReceiverHandler.java

@@ -37,6 +37,7 @@
 import java.security.PrivateKey;
 import java.security.cert.X509Certificate;
 import java.util.Enumeration;
+import java.util.Locale;
 import java.util.function.Consumer;
 
 import org.bouncycastle.cms.CMSException;
@@ -565,26 +566,15 @@ public void handleIncomingMessage (@Nonnull final String sClientInfo,
                                               () -> AbstractActiveNetModule.DISP_PARTNERSHIP_NOT_FOUND);
         }
 
-        // Calculate MIC before decrypt and decompress (see #140)
-        try
-        {
-          aIncomingMIC = AS2Helper.createMICOnReception (aMsg);
-        }
-        catch (final Exception ex)
-        {
-          // Ignore error
-          throw WrappedAS2Exception.wrap (ex);
-        }
+        // Decrypt and verify signature of the data, and attach data to the
+        // message
+        decrypt (aMsg, aResHelper);
 
         // Per RFC5402 compression is always before encryption but can be before
         // or after signing of message but only in one place
         final ICryptoHelper aCryptoHelper = AS2Helper.getCryptoHelper ();
-        boolean bIsDecompressed = false;
-
-        // Decrypt and verify signature of the data, and attach data to the
-        // message
-        decrypt (aMsg, aResHelper);
 
+        boolean bIsDecompressed = false;
         if (aCryptoHelper.isCompressed (aMsg.getContentType ()))
         {
           if (LOGGER.isTraceEnabled ())
@@ -596,6 +586,46 @@ public void handleIncomingMessage (@Nonnull final String sClientInfo,
         // Verify may fail, if our certificate is expired
         verify (aMsg, aResHelper);
 
+        // Calculate MIC state signed by the sender (might have been compressed
+        // or not) (see #140)
+        // Do this only after the partnership was determined
+        // Do this after decryption
+        final boolean bIsSigned = aCryptoHelper.isSigned (aMsg.getData ());
+        if (bIsSigned)
+          try
+          {
+
+            // Copy all Content-related headers to the MIME part. Maintain the order of the source
+            // message. This is relevant for MIC calculation
+            if (true)
+              aMsg.headers ().forEachSingleHeader ( (k, v) -> {
+                if (k.toLowerCase (Locale.ROOT).startsWith ("content-") &&
+                    !CHttpHeader.CONTENT_TYPE.equalsIgnoreCase (k) &&
+                    !CHttpHeader.CONTENT_LENGTH.equalsIgnoreCase (k))
+                  try
+                  {
+                    // Don't overwrite
+                    if (aMsg.getData ().getHeader (k) == null)
+                    {
+                      LOGGER.info ("  Setting MIME part header '" + k + "' to '" + v + "'");
+                      aMsg.getData ().setHeader (k, v);
+                    }
+                  }
+                  catch (final MessagingException ex)
+                  {
+                    LOGGER.error ("Error storing header '" + k + "' with value '" + v + "' in MimeBodyPart");
+                  }
+              }, false);
+
+            // From signed payload
+            aIncomingMIC = AS2Helper.createMICOnReception (aMsg);
+          }
+          catch (final Exception ex)
+          {
+            // Ignore error
+            throw WrappedAS2Exception.wrap (ex);
+          }
+
         if (aCryptoHelper.isCompressed (aMsg.getContentType ()))
         {
           // Per RFC5402 compression is always before encryption but can be
@@ -616,6 +646,18 @@ public void handleIncomingMessage (@Nonnull final String sClientInfo,
           bIsDecompressed = true;
         }
 
+        if (!bIsSigned)
+          try
+          {
+            // From uncompressed payload
+            aIncomingMIC = AS2Helper.createMICOnReception (aMsg);
+          }
+          catch (final Exception ex)
+          {
+            // Ignore error
+            throw WrappedAS2Exception.wrap (ex);
+          }
+
         if (LOGGER.isTraceEnabled ())
           try
           {