Author: markt
Date: Fri May 15 10:24:11 2015
New Revision: 1679534

URL: http://svn.apache.org/r1679534
Log:
Fix a problem with SPNEGO auth and Java 8 update 40 onwards.

Modified:
    tomcat/trunk/java/org/apache/catalina/authenticator/SpnegoAuthenticator.java
    tomcat/trunk/webapps/docs/config/valve.xml

Modified: 
tomcat/trunk/java/org/apache/catalina/authenticator/SpnegoAuthenticator.java
URL: 
http://svn.apache.org/viewvc/tomcat/trunk/java/org/apache/catalina/authenticator/SpnegoAuthenticator.java?rev=1679534&r1=1679533&r2=1679534&view=diff
==============================================================================
--- 
tomcat/trunk/java/org/apache/catalina/authenticator/SpnegoAuthenticator.java 
(original)
+++ 
tomcat/trunk/java/org/apache/catalina/authenticator/SpnegoAuthenticator.java 
Fri May 15 10:24:11 2015
@@ -22,6 +22,7 @@ import java.security.Principal;
 import java.security.PrivilegedAction;
 import java.security.PrivilegedActionException;
 import java.security.PrivilegedExceptionAction;
+import java.util.LinkedHashMap;
 import java.util.regex.Pattern;
 
 import javax.security.auth.Subject;
@@ -91,6 +92,14 @@ public class SpnegoAuthenticator extends
         }
     }
 
+    private boolean applyJava8u40Fix = true;
+    public boolean getApplyJava8u40Fix() {
+        return applyJava8u40Fix;
+    }
+    public void setApplyJava8u40Fix(boolean applyJava8u40Fix) {
+        this.applyJava8u40Fix = applyJava8u40Fix;
+    }
+
 
     @Override
     protected String getAuthMethod() {
@@ -164,6 +173,10 @@ public class SpnegoAuthenticator extends
                 authorizationBC.getOffset(),
                 authorizationBC.getLength());
 
+        if (getApplyJava8u40Fix()) {
+            SpnegoTokenFixer.fix(decoded);
+        }
+
         if (decoded.length == 0) {
             if (log.isDebugEnabled()) {
                 log.debug(sm.getString(
@@ -331,4 +344,153 @@ public class SpnegoAuthenticator extends
             return realm.authenticate(gssContext, storeDelegatedCredential);
         }
     }
+
+
+    /**
+     * This class implements a hack around an incompatibility between the
+     * SPNEGO implementation in Windows and the SPNEGO implementation in Java 8
+     * update 40 onwards. It was introduced by the change to fix this bug:
+     * https://bugs.openjdk.java.net/browse/JDK-8048194
+     * (note: the change applied is not the one suggested in the bug report)
+     * <p>
+     * It is not clear to me if Windows, Java or Tomcat is at fault here. I
+     * think it is Java but I could be wrong.
+     * <p>
+     * This hack works by re-ordering the list of mechTypes in the NegTokenInit
+     * token.
+     */
+    private static class SpnegoTokenFixer {
+
+        public static void fix(byte[] token) {
+            SpnegoTokenFixer fixer = new SpnegoTokenFixer(token);
+            fixer.fix();
+        }
+
+
+        private final byte[] token;
+        private int pos = 0;
+
+
+        private SpnegoTokenFixer(byte[] token) {
+            this.token = token;
+        }
+
+
+        // Fixes the token in-place
+        private void fix() {
+            /*
+             * Useful references:
+             * http://tools.ietf.org/html/rfc4121#page-5
+             * http://tools.ietf.org/html/rfc2743#page-81
+             * https://msdn.microsoft.com/en-us/library/ms995330.aspx
+             */
+
+            // Scan until we find the mech types list. If we find anything
+            // unexpected, abort the fix process.
+            if (!tag(0x60)) return;
+            if (!length()) return;
+            if (!oid("1.3.6.1.5.5.2")) return;
+            if (!tag(0xa0)) return;
+            if (!length()) return;
+            if (!tag(0x30)) return;
+            if (!length()) return;
+            if (!tag(0xa0)) return;
+            lengthAsInt();
+            if (!tag(0x30)) return;
+            // Now at the start of the mechType list.
+            // Read the mechTypes into an ordered set
+            int mechTypesLen = lengthAsInt();
+            int mechTypesStart = pos;
+            LinkedHashMap<String, int[]> mechTypeEntries = new 
LinkedHashMap<>();
+            while (pos < mechTypesStart + mechTypesLen) {
+                int[] value = new int[2];
+                value[0] = pos;
+                String key = oidAsString();
+                value[1] = pos - value[0];
+                mechTypeEntries.put(key, value);
+            }
+            // Now construct the re-ordered mechType list
+            byte[] replacement = new byte[mechTypesLen];
+            int replacementPos = 0;
+
+            int[] first = mechTypeEntries.remove("1.2.840.113554.1.2.2");
+            if (first != null) {
+                System.arraycopy(token, first[0], replacement, replacementPos, 
first[1]);
+                replacementPos += first[1];
+            }
+            for (int[] markers : mechTypeEntries.values()) {
+                System.arraycopy(token, markers[0], replacement, 
replacementPos, markers[1]);
+                replacementPos += markers[1];
+            }
+
+            // Finally, replace the original mechType list with the re-ordered
+            // one.
+            System.arraycopy(replacement, 0, token, mechTypesStart, 
mechTypesLen);
+        }
+
+
+        private boolean tag(int expected) {
+            return (token[pos++] & 0xFF) == expected;
+        }
+
+
+        private boolean length() {
+            // No need to retain the length - just need to consume it and make
+            // sure it is valid.
+            int len = lengthAsInt();
+            return pos + len == token.length;
+        }
+
+
+        private int lengthAsInt() {
+            int len = token[pos++] & 0xFF;
+            if (len > 127) {
+                int bytes = len - 128;
+                len = 0;
+                for (int i = 0; i < bytes; i++) {
+                    len = len << 8;
+                    len = len + (token[pos++] & 0xff);
+                }
+            }
+            return len;
+        }
+
+
+        private boolean oid(String expected) {
+            return expected.equals(oidAsString());
+        }
+
+
+        private String oidAsString() {
+            if (!tag(0x06)) return null;
+            StringBuilder result = new StringBuilder();
+            int len = lengthAsInt();
+            // First byte is special case
+            int v = token[pos++] & 0xFF;
+            int c2 = v % 40;
+            int c1 = (v - c2) / 40;
+            result.append(c1);
+            result.append('.');
+            result.append(c2);
+            int c = 0;
+            boolean write = false;
+            for (int i = 1; i < len; i++) {
+                int b = token[pos++] & 0xFF;
+                if (b > 127) {
+                    b -= 128;
+                } else {
+                    write = true;
+                }
+                c = c << 7;
+                c += b;
+                if (write) {
+                    result.append('.');
+                    result.append(c);
+                    c = 0;
+                    write = false;
+                }
+            }
+            return result.toString();
+        }
+    }
 }

Modified: tomcat/trunk/webapps/docs/config/valve.xml
URL: 
http://svn.apache.org/viewvc/tomcat/trunk/webapps/docs/config/valve.xml?rev=1679534&r1=1679533&r2=1679534&view=diff
==============================================================================
--- tomcat/trunk/webapps/docs/config/valve.xml (original)
+++ tomcat/trunk/webapps/docs/config/valve.xml Fri May 15 10:24:11 2015
@@ -1438,6 +1438,17 @@
 
     <attributes>
 
+      <attribute name="applyJava8u40Fix" required="false">
+        <p>A fix introduced in Java 8 update 40 (
+        <a 
href="https://bugs.openjdk.java.net/browse/JDK-8048194";>JDK-8048194</a>)
+        onwards broke SPNEGO authentication for IE with Tomcat running on
+        Windows 2008 R2 servers. This option enables a work-around that allows
+        SPNEGO authentication to continue working. The work-around should not
+        impact other configurations so it is enabled by default. If necessary,
+        the workaround can be disabled by setting this attribute to
+        <code>false</code>.</p>
+      </attribute>
+
       <attribute name="alwaysUseSession" required="false">
         <p>Should a session always be used once a user is authenticated? This
         may offer some performance benefits since the session can then be used



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