----- Original Message -----
> On 5/20/2013 5:28 PM, Pasi Eronen wrote:
> > Hi Xuelei,
> > 
> > It seems the PKSC11 doesn't actually have this bug.
> > 
> > P11KeyAgreement has a separate code path for the "TlsPremasterSecret"
> > algorithm, which strips leading zeroes if the key can be extracted from
> > the token. (And if the key cannot be extracted, then the token is doing
> > the premaster secret->master secret computation, and has to do the
> > stripping -- it can't be done from the Java PKSC11 provider.)
> > 
> It makes sense to me.
> 
> > To make sure this behavior doesn't change, I added a test case
> > for the PKSC11 provider to the Bugzilla (which passes with the
> > "SunPKCS11-NSS" provider without any changes).
> > 
> That's great.  Would you mind to contribute the regression test for
> PKCS11 provider?
> 

It's been attached to the bug report: 
https://bugs.openjdk.java.net/show_bug.cgi?id=100316

Is there any reason the original patch can't be committed?  I haven't seen any 
mentioned.

> Thanks,
> Xuelei
> 
> > Best regards,
> > Pasi
> > 
> > 
> > 
> > On Thu, May 16, 2013 at 10:56 AM, Xuelei Fan <xuelei....@oracle.com
> > <mailto:xuelei....@oracle.com>> wrote:
> > 
> >     Hi Pasi,
> > 
> >     Thank you for your patience, and contribution to OpenJDK.  The bug is
> >     accepted, and you should be able to review it at:
> > 
> >        http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8014618
> > 
> >     Let's use the above bug ID to track the issue.
> > 
> >     Your patch looks fine in general (I may have some very minor comments
> >     later).  We also have similar problems in PKCS11 provider because of
> >     the
> >     update of P11KeyAgreement.java in changeset:
> > 
> >         http://hg.openjdk.java.net/jdk7u/jdk7u-gate/jdk/rev/e574e475c8a6
> > 
> >     Would you like to also fix it in your patch?
> > 
> >     Thanks again for your nice work.
> > 
> >     Regards,
> >     Xuelei
> > 
> > 
> >     On 5/10/2013 5:00 PM, Pasi Eronen wrote:
> >     > AKA "1 out of 256 SSL/TLS handshakes fails with DHE cipher suites"
> >     >
> >     > I reported this bug over a month of ago, but for some reason, it's
> >     > not
> >     > yet visible at bugs.sun.com <http://bugs.sun.com>
> >     <http://bugs.sun.com>. I've included the bug
> >     > report below just in
> >     > case.
> >     >
> >     > It seems this commit from March 2012 inadvertently broke SSL/TLS DHE
> >     > cipher suites, causing the SSL/TLS handshake to fail approximately
> >     > 1 out of 256 times:
> >     >
> >     > http://hg.openjdk.java.net/jdk7u/jdk7u-gate/jdk/rev/e574e475c8a6
> >     >
> >     > The commit was done to fix this bug:
> >     >
> >     > http://bugs.sun.com/view_bug.do?bug_id=7146728
> >     >
> >     > While generating a secret of the same length as modulus may be the
> >     right
> >     > choice generally speaking (and it's what e.g. IPsec uses), SSL/TLS
> >     uses
> >     > a different convention: leading zeroes must be stripped.
> >     >
> >     > This is currently blocking us from updating our production systems to
> >     > Java 7, so although I have not contributed to OpenJDK before, I'd
> >     > like
> >     > to submit a patch and a test case for this (I've signed the OCA
> >     > already). But before I do this, I'd like to check that the approach
> >     > is
> >     > agreeable.
> >     >
> >     > We have a separate "algorithm" value "TlsPremasterSecret", so
> >     > behavior for other cases could stay the same. Would a patch
> >     > like this:
> >     >
> >     >     } else if (algorithm.equals("TlsPremasterSecret")) {
> >     >         // remove leading zero bytes per RFC 5246 Section 8.1.2
> >     >         int i = 0;
> >     >         while ((i < secret.length - 1) && (secret[i] == 0)) {
> >     >             i++;
> >     >         }
> >     >         if (i == 0) {
> >     >             return new SecretKeySpec(secret, "TlsPremasterSecret");
> >     >         } else {
> >     >             byte[] secret2 = new byte[secret.length - i];
> >     >             System.arraycopy(secret, i, secret2, 0, secret2.length);
> >     >             return new SecretKeySpec(secret2, "TlsPremasterSecret");
> >     >         }
> >     >     }
> >     >
> >     > Plus a test case (with fixed keys) that checks that leading zero is
> >     > stripped
> >     > for TlsPremasterSecret and is not stripped otherwise, be sufficient?
> >     >
> >     > Best regards,
> >     > Pasi
> >     >
> >     > ---snip---
> >     >
> >     > Synopsis:
> >     > DHKeyAgreement calculates wrong TlsPremasterSecret 1 out of 256 times
> >     >
> >     > Full OS version:
> >     > Tested on Windows 7 (Microsoft Windows [Version 6.1.7601]), but
> >     occurs in
> >     > e..g OpenJDK 7 as well.
> >     >
> >     > Development Kit or Runtime version:
> >     > java version "1.7.0_17"
> >     > Java(TM) SE Runtime Environment (build 1.7.0_17-b02)
> >     > Java HotSpot(TM) Client VM (build 23.7-b01, mixed mode, sharing)
> >     >
> >     > Description:
> >     > When performing Diffie-Hellman key agreement for SSL/TLS, the TLS
> >     > specification (RFC 5246) says that "Leading bytes of Z that
> >     contain all zero
> >     > bits are stripped before it is used as the pre_master_secret."
> >     >
> >     > However, com.sun.crypto.provider.DHKeyAgreement.java does not
> >     strip leading
> >     > zero bytes. This causes approximately 1 out 256 SSL/TLS handshakes
> >     with
> >     > DH/DHE cipher suites to fail (when the leading byte happens, by
> >     chance, to
> >     > be zero).
> >     >
> >     > Steps to Reproduce:
> >     > 1. Start a simple JSSE socket server with -Djavax.net.debug=all.
> >     >
> >     > 2. Connect to the server with e.g. OpenSSL command line tool,
> >     ensuring that
> >     > DHE cipher suite gets selected (e.g. "openssl s_client -cipher
> >     > DHE-RSA-AES128-SHA -connect 192.168.81.1:9999
> >     <http://192.168.81.1:9999>
> >     > <http://192.168.81.1:9999>") repeatedly. Other SSL
> >     > clients can be used -- this is not an OpenSSL bug (see below).
> >     >
> >     > 3. Repeat the connection. After a couple of hundred successful
> >     connections,
> >     > the connection will fail with handshake_failure alert.
> >     >
> >     > 4. Examine the JSSE debug logs produced by the server: the failed
> >     connection
> >     > will have a PreMaster secret that begins with zero byte
> >     > (while all other connections have non-zero byte here). For example:
> >     >
> >     > SESSION KEYGEN:
> >     > PreMaster Secret:
> >     > 0000: 00 70 C5 7E 91 38 C8 DE   ED 75 3D 76 8A B5 44 69
> >      .p...8...u=v..Di
> >     > 0010: E7 32 1C EE 80 77 50 C7   A9 51 24 2E E3 15 11 30
> >      .2...wP..Q$....0
> >     > 0020: 9D F6 9F BC 9D EB 5C 18   F7 A4 19 ED 1A AC 2E 0C
> >      ......\.........
> >     > 0030: E3 18 C5 11 B1 80 07 7D   B1 C6 70 A8 D7 EB CF DD
> >      ..........p.....
> >     > 0040: 2D B5 1D BC 01 3E 28 2A   2B 5B 38 8F EB 20 F2 A2
> >      -....>(*+[8.. ..
> >     > 0050: 00 07 47 F7 87 B8 99 CB   EF B4 13 04 C8 8B 82 FB
> >      ..G.............
> >     >
> >     > Expected Result:
> >     > Expected result is that every connection succeed.
> >     >
> >     > Actual Result:
> >     > Roughly one out of 256 connections fail.
> >     >
> >     > Source code for an executable test case:
> >     >
> >     > Java server:
> >     >
> >     > import javax.net.ssl.SSLServerSocket;
> >     > import javax.net.ssl.SSLServerSocketFactory;
> >     > import javax.net.ssl.SSLSocket;
> >     >
> >     > public class TestServer {
> >     >     public static void main(String args[]) throws Exception {
> >     >         SSLServerSocketFactory ssf = (SSLServerSocketFactory)
> >     > SSLServerSocketFactory.getDefault();
> >     >         SSLServerSocket ss = (SSLServerSocket)
> >     ssf.createServerSocket(9999);
> >     >         System.out.println("Listening on port 9999");
> >     >         for (String cs : ss.getEnabledCipherSuites()) {
> >     >             System.out.println(cs);
> >     >         }
> >     >         while (true) {
> >     >             SSLSocket s = (SSLSocket) ss.accept();
> >     >             System.out.println("Connected with
> >     > "+s.getSession().getCipherSuite());
> >     >             s.close();
> >     >         }
> >     >     }
> >     > }
> >     >
> >     > Run as as follows:
> >     >
> >     > keytool -storepass "password" -keypass "password" -genkey -keyalg RSA
> >     > -keystore test_keystore.jks -dname CN=test
> >     > javac TestServer.java
> >     > java -Djavax.net.debug=all
> >     -Djavax.net.ssl.keyStore=./test_keystore.jks
> >     > -Djavax.net.ssl.keyStorePassword=password TestServer
> >     >
> >     > OpenSSL client:
> >     >
> >     > set -e
> >     > while true; do
> >     >   openssl s_client -cipher DHE-RSA-AES128-SHA -connect
> >     127.0.0.1:9999 <http://127.0.0.1:9999>
> >     > <http://127.0.0.1:9999> -quiet -no_ign_eof < /dev/null
> >     > done
> >     >
> >     > Workaround:
> >     > Disable Diffie-Hellman cipher suites.
> >     >
> >     > ---snip---
> >     >
> > 
> > 
> 
> 

-- 
Andrew :)

Free Java Software Engineer
Red Hat, Inc. (http://www.redhat.com)

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