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<div class="moz-cite-prefix">On 8/18/2016 4:49 PM, Valerie Peng
wrote:<br>
</div>
<blockquote
cite="mid:4a33b5ec-816e-5ee5-ae77-f865c6b42fb3@oracle.com"
type="cite">
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
Hi Mike,<br>
<br>
Thanks for the feedback and the detailed write up.<br>
<br>
The scenario here is complicated by the sensitive/non-extractable
keys of PKCS#11 and the fact that java key and key specification
classes assume all relevant values being available.</blockquote>
Um... I think that's true for any PublicKey, but not for Secret or
Private keys. At worst, the Key object is a handle for the real key
that contains all those items, but they might not be available. At
best, most of those components will be available. I say at best,
because of the language in RSAMultiPrimePrivateCRTKey for
getOtherPrimeInfo() which says it can return null.<br>
<br>
<blockquote
cite="mid:4a33b5ec-816e-5ee5-ae77-f865c6b42fb3@oracle.com"
type="cite"> Only when all relevant values are available, then we
will construct the corresponding key objects. This is necessary as
there are other providers which may receive such keys and they
can't handle keys like this.<br>
</blockquote>
<br>
Keys can't generally move across providers AIRC? You can try and
use a key factory to convert them, but that's not guaranteed. A
PKCS11 derived key isn't going to be portable to another provider
without extraction to a keyspec in any case. <br>
<br>
Hmm.. I went back and read the JDK8 p11 guide
(<a class="moz-txt-link-freetext" href="https://docs.oracle.com/javase/8/docs/technotes/guides/security/p11guide.html">https://docs.oracle.com/javase/8/docs/technotes/guides/security/p11guide.html</a>)
and section 3.2 gives the guidance that you only use the generic
interfaces for unextractable keys. I actually think that's wrong,
given the general guidance in the JCA documentation with respect to
Opaque Keys vs transparent KeySpecs. (Hmm... I wonder if this
guidance was in the originally submitted code package
documentation).<br>
<br>
Then there's the point that even a generic Public or Private key has
a "getEncoded()" method. *bleah*<br>
<br>
<br>
<blockquote
cite="mid:4a33b5ec-816e-5ee5-ae77-f865c6b42fb3@oracle.com"
type="cite"> <br>
I am sure that the current PKCS11 provider code needs many
improvement/finer handlings. But I don't see a straightforward way
of "making CKA_PUBLIC_EXPONENT available" across various RSA Key
classes. This should be tracked in a different issue.<br>
</blockquote>
<br>
That's just one of the items. As I mentioned in another email, I
think the RSA key classes and interfaces need a bit more work and
tweaking. I wouldn't try and accomplish that quite yet.<br>
<br>
<blockquote
cite="mid:4a33b5ec-816e-5ee5-ae77-f865c6b42fb3@oracle.com"
type="cite"> <br>
Given the current release schedule, the deadline for this fix (P4)
is coming up in 10 days and I will be on vacation next week.<br>
<br>
If you agree with the value of addressing this with the proposed
changes for JDK 9, then we can proceed.<br>
Otherwise, I will defer this bug to the update release and we can
spend more time to polish this.<br>
</blockquote>
<br>
I think you might as well go ahead with this change. The fix you've
got should work as long as someone who generates a RSA Key pair on a
PKCS11 which is both sensitive and unextractable doesn't try to cast
the keys to RSAPublic or RSAPrivate.<br>
<br>
Mike<br>
<br>
<br>
<blockquote
cite="mid:4a33b5ec-816e-5ee5-ae77-f865c6b42fb3@oracle.com"
type="cite"> Valerie<br>
<br>
<div class="moz-cite-prefix">On 8/18/2016 8:40 AM, Michael StJohns
wrote:<br>
</div>
<blockquote
cite="mid:851c0000-8341-294c-e62b-f15334d417a1@comcast.net"
type="cite">
<meta content="text/html; charset=utf-8"
http-equiv="Content-Type">
<div class="moz-cite-prefix">On 8/17/2016 11:36 PM, Valerie Peng
wrote:<br>
</div>
<blockquote
cite="mid:89d1e859-a988-627d-6b7c-c5ad6f062f18@oracle.com"
type="cite">
<meta content="text/html; charset=utf-8"
http-equiv="Content-Type">
Regression tests are still running, but thought that I will
send the updated webrev out and see if there are more
comments.<br>
<br>
Webrev is updated at: <a moz-do-not-send="true"
class="moz-txt-link-freetext"
href="http://cr.openjdk.java.net/%7Evaleriep/8078661/webrev.01/">http://cr.openjdk.java.net/~valeriep/8078661/webrev.01/</a><br>
<br>
Thanks,<br>
Valerie<br>
</blockquote>
Hi Valerie - <br>
<br>
You know - re-reading this code I'm reminding of why PKCS11
annoys me so much.<br>
<br>
At line 333 (of the "new" P11Key) you grab the Token, Sensitive
and Extractable values and if the private data is sensitive or
not extractable you create a generic P11PrivateKey and return
that. However the contract for RSAKey requires that the public
modulus be returned if available, and, since its not a sensitive
attribute it probably should be available. Also, even if the
key is sensitive - if its a sensitive CRT key, then
CKA_PUBLIC_EXPONENT should be available.<br>
<br>
That's going to be a surprise if someone tries to cast this
return to an (RSAKey) or (RSAPrivateKey). <u>This should be
changed so a key of the appropriate type is always created.</u><br>
<br>
Also, checking for CKA_EXTRACTABLE being true, doesn't actually
get you access to the clear text information. If a key is
extractable, then it can be wrapped out under another key. The
components themselves aren't available. It's possible to have a
non-sensitive, non-extractable key where the components are
retrievable, but the key can't be wrapped out.<br>
<br>
<br>
(Hmm... the public exponent is in RSAPublicKey and
RSAPrivateCRTKey, but should probably be in RSAKey instead).<br>
<br>
So:<br>
<br>
All RSA keys - even the sensitive private ones - should return
CKA_MODULUS.<br>
All RSA Private CRT Keys - even the sensitive ones - should also
return CKA_PUBLIC_EXPONENT.<br>
All non-sensitive RSA Private keys - should also return
CKA_PRIVATE_EXPONENT<br>
All non-sensitive RSA Private CRT Keys - should also return
CKA_PRIME_1, CKA_PRIME_2, CKA_EXPONENT_1, CKA_EXPONENT_2 and
CKA_COEFFICIENT.<br>
<br>
This is harder to do than it needs to be due to how
p11_objmgt.c::Java_sun_security_pkcs11_wrapper_PKCS11_C_1GetAttributeValue
is built. At lines 248 and 270, it does a check for an error
return and throws an exception if any error occurs. However,
for C_GetAttributeValue, there are a number of "non-fatal"
errors that indicate either buffer size errors or sensitivity of
one or more components or unavailability of one or more
components.<br>
<blockquote type="cite">Note that the error codes
CKR_ATTRIBUTE_SENSITIVE, CKR_ATTRIBUTE_TYPE_INVALID, and
CKR_BUFFER_TOO_SMALL do not denote true errors for <b>C_GetAttributeValue</b>.
If a call to <b>C_GetAttributeValue</b> returns any of these
three values, then the call must nonetheless have processed <i>every</i>
attribute in the template supplied to <b>C_GetAttributeValue</b>.
Each attribute in the template whose value <i>can be</i>
returned by the call to <b>C_GetAttributeValue</b> <i>will
be</i> returned by the call to <b>C_GetAttributeValue</b>.</blockquote>
<br>
<br>
<br>
If you updated this slightly - maybe by adding a new method to
wrapper.PKCS11 (say GetAttributeValuesNoError) - to return the
attributes it was able to get in the call with nulls elsewhere,
then you could do all of the above in one pass. <br>
<br>
Sorry to complicate this. Mike<br>
<br>
ps - I don't have a current build environment set up for the
JDK, otherwise I'd code it and test it myself. I'm happy to
take a swing at it and provide you unverified code you can
integrate.<br>
<br>
<blockquote
cite="mid:89d1e859-a988-627d-6b7c-c5ad6f062f18@oracle.com"
type="cite"> <br>
<div class="moz-cite-prefix">On 8/17/2016 9:55 AM, Michael
StJohns wrote:<br>
</div>
<blockquote
cite="mid:d605af02-3f3b-8fb5-4bbd-ebbd836457cc@comcast.net"
type="cite">
<meta content="text/html; charset=utf-8"
http-equiv="Content-Type">
<div class="moz-cite-prefix">On 8/16/2016 9:24 PM, Valerie
Peng wrote:<br>
</div>
<blockquote
cite="mid:f2065a91-b1bd-f55b-7e1f-055752fcdfe9@oracle.com"
type="cite"> <br>
Anyone has time to review a straightforward fix? The
current PKCS11 code assume that if public exponent is
available for RSA Private Key, then it's a RSA CRT key.
However, not all vendor implementation works this way.
Changing to a tighter check and did minor code-refactoring
to avoid re-retrieving the attribute values. <br>
<br>
Bug: <a moz-do-not-send="true"
class="moz-txt-link-freetext"
href="https://bugs.openjdk.java.net/browse/JDK-8078661">https://bugs.openjdk.java.net/browse/JDK-8078661</a>
<br>
Webrev: <a moz-do-not-send="true"
class="moz-txt-link-freetext"
href="http://cr.openjdk.java.net/%7Evaleriep/8078661/webrev.00/">http://cr.openjdk.java.net/~valeriep/8078661/webrev.00/</a>
<br>
<br>
Thanks, <br>
Valerie <br>
</blockquote>
<p>Given that there's a change to PKCS11 for 2.40 that says
that all RSA private key objects MUST also store
CKA_PUBLIC_EXPONENT, some change needed to be made.</p>
<p>Sorry - I don't think this fix will work. Or if its
working on your version of PKCS11, your version of PKCS11
is doing it wrong. The problem is that if you specify
attributes that don't exist on the object, the underlying
PKCS11 library is supposed to return
CKR_ATTRIBUTE_TYPE_INVALID. And that should trigger a
thrown exception before you ever get anything copied to
your attributes.</p>
<p>1) Get modulus and private exponent first. That gives
you the stuff for a generic RSA private key - and if it
fails, there's no reason to continue.</p>
<p>2) Then get the rest of the stuff. If that fails, then
you already have the stuff you need for a normal private
key.<br>
</p>
<p> <br>
</p>
<p> </p>
<blockquote type="cite">
<pre> boolean crtKey;
try {
session.token.p11.C_GetAttributeValue
(session.id(), keyID, attrs2);
<span class="removed">- crtKey = (attrs2[0].pValue instanceof byte[]);</span>
<span class="new">+ crtKey = ((attrs2[1].pValue instanceof byte[]) &&</span>
<span class="new">+ (attrs2[3].pValue instanceof byte[]) &&</span>
<span class="new">+ (attrs2[4].pValue instanceof byte[]) &&</span>
<span class="new">+ (attrs2[5].pValue instanceof byte[]) &&</span>
<span class="new">+ (attrs2[6].pValue instanceof byte[]) &&</span>
<span class="new">+ (attrs2[7].pValue instanceof byte[])) ;</span>
} catch (PKCS11Exception e) {
// ignore, assume not available
crtKey = false;
}</pre>
</blockquote>
<p>// Change attrs2 so it only has the additional CRT
attributes (e.g. delete CKA_MODULUS, CKA_PRIVATE_EXPONENT
from the list<br>
</p>
<p>Replace the above with <br>
</p>
<p>CK_ATTRIBUTE[] attrs3 = new CK_ATTRIBUTE[] {<br>
new CK_ATTRIBUTE(CKA_MODULUS),<br>
new CK_ATTRIBUTE(CKA_PRIVATE_EXPONENT)<br>
};<br>
// no try block needed here - we want to throw the error
if it occurs<br>
session.token.p11.C_GetAttributeValue (session.id(),
keyID, attrs3);</p>
<p>// So far so good - we have the base attributes, let's
see if we can get the additional attributes;</p>
<p>try { <br>
session.token.p11.C_GetAttributeValue(session.id(),keyID,
attrs2);<br>
} catch (PKCS11Exception e) {<br>
// we really should check the return value for one of
the non-fatal values, but let's just assume its not a CRT
key<br>
return new P11RSAPrivateNonCRTKey (session, keyID,
algorithm, keyLength, attrs2, attrs3);<br>
}</p>
<p>// if we fall through then its a CRT key<br>
// -- we should check for byte[] ness of each of the
components, and throw an error if they arent - but which
error?</p>
<p>return new P11RSAPrivateKey (session, keyID, algorithm,
keyLength, attrs2, attrs3);<br>
</p>
<p>// there are cleanups necessary in other places. I'd
suggest rather than depending on the ordering of
attributes, you do assignment by CKA_ values just so
someone coming later doesn't mess things up by mistake.
Also, a hell of a lot more readable.<br>
</p>
<p>static CK_ATTRIBUTE getAttribute (CK_ATTRIBUTE[] attrs,
long attrType) {<br>
for (CK_ATTRIBUTE a : attrs) {<br>
if (a.type == attrType)<br>
return a;<br>
}<br>
return null; // or throw something?<br>
}<br>
</p>
<p><br>
coeff =
getAtttribute(attrs,CKA_COEFFICIENT).getBigInteger();<br>
</p>
<br>
The other possibility is to change the C code for
C_GetAttributeValues so it doesn't error out for the
non-fatal error codes and instead returns a null value
attribute when the attribute is missing.<br>
<br>
Mike<br>
<br>
</blockquote>
<br>
</blockquote>
<p><br>
</p>
</blockquote>
<br>
</blockquote>
<p><br>
</p>
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