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<br>
This is a working document for progress on Stan design/development.<br>
<br>
Current <a href="#build">build</a>
and <a href="#test">test</a>
instructions.<br>
<br>
The current set of Stan libraries.<br>
<a href="#asn1">asn1</a>
<br>
<a href="#base">base</a>
<br>
<a href="#ckfw">ckfw</a>
<br>
<a href="#dev">dev</a>
<br>
<a href="#pki">pki</a>
<br>
<a href="#pki1">pki1</a>
<br>
<a href="#pkix">pkix</a>
<br>
<br>
"Public" types below (those available to consumers of
NSS) begin with "NSS". &nbsp;"Protected" types (those only available
within NSS) begin with "nss".<br>
<br>
Open issues appears as numbered indents.<br>
<br>
<br>
<hr width="100%" size="2" align="Left"><br>
<h3><a name="asn1"></a>
ASN.1</a>
</h3>
ASN.1 encoder/decoder wrapping around the current
ASN.1 implementation.<br>
<br>
<br>
<br>
<br>
nssASN1ChooseTemplateFunction</a>
<br>
<br>
<br>
<br>
nssASN1NotifyFunction</a>
<br>
nssASN1EncoderWriteFunction</a>
<br>
nssASN1DecoderFilterFunction</a>
<br>
<br>
<hr width="100%" size="2" align="Left">
<h3><a name="base"></a>
Base</a>
</h3>
Set of base utilities for Stan implementation.
&nbsp;These are all fairly straightforward, except for nssPointerTracker.<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
This is intended for debug builds only.<br>
<ol>
<li>Ignored for now.<br>
</li>
</ol>
<br>
<br>
Suggested additions:<br>
<ol>
<li>nssList - A list that optionally uses a lock. &nbsp;This list would
manage the currently loaded modules in a trust domain, etc.</li>
<ul>
<li>SECMODListLock kept track of the number of waiting threads. &nbsp;Will
this be needed in the trust domain?</li>
</ul>
</ol>
<br>
<hr width="100%" size="2" align="Left">
<h3><a name="ckfw"></a>
CKFW</a>
</h3>
The cryptoki framework, used for building cryptoki tokens.
&nbsp;This needs to be described in a separate document showing how
to set up a token using CKFW. &nbsp;This code only relates to tokens,
so it is not relevant here.<br>
<br>
<br>
<hr width="100%" size="2" align="Left">
<h3><a name="dev"></a>
Device</a>
</h3>
Defines cryptoki devices used in NSS. &nbsp;This
is not part of the exposed API. &nbsp;It is a low-level API allowing
NSS to manage cryptoki devices.<br>
<br>
The relationship is like this:<br>
<br>
libpki --&gt; libdev --&gt; cryptoki<br>
<br>
As an example,<br>
<br>
NSSTrustDomain_FindCertificate --&gt; NSSToken_FindCertificate --&gt;
C_FindObjects<br>
<br>
<br>
Replaces the SECMOD API. &nbsp;The module manages a
PRLibrary that holds a cryptoki implementation via a number of slots.
&nbsp;The API should provide the ability to Load and Unload a module,
Login and Logout to the module (through its slots), and to locate a
particular slot/token.<br>
<br>
<br>
This and NSSToken combine to replace the PK11 API parts
that relate to slot and token management. &nbsp;The slot API should
provide the ability to Login/Logout to a slot, check the login status,
determine basic configuration information about the slot, and modify
the password settings.<br>
<ol>
<li>Should slots also maintain a default session? &nbsp;This session would
be used for slot management calls (sections 9.5 and9.6 of PKCS#11). &nbsp;Or
is the token session sufficient (this would not work if C_GetTokenInfo and
C_InitToken need to be wrapped in a threadsafe session).<br>
</li>
</ol>
<br>
<br>
Fills in the gaps left by NSSSlot. &nbsp;Much of the
cryptoki API is directed towards slots. &nbsp;However, some functionality
clearly belongs with a token type. &nbsp;For example, a certificate
lives on a token, not a slot, so one would expect a function NSSToken_FindCertificate.
&nbsp;Thus functions that deal with importing/exporting an object
and performing actual cryptographic operations belong here.<br>
<ol>
<li>The distinction between a slot and a token is not clear. &nbsp;Most
functions take a slotID as an argument, even though it is obvious that
the event is intended to occur on a token. &nbsp;That leaves various
possibilities:</li>
<ol>
<li>Implement the API entirely as NSSToken. &nbsp;If the token is not
present, some calls will simply fail.</li>
<li>Divide the API between NSSToken and NSSSlot, as described above.
&nbsp;NSSSlot would handle cryptoki calls specified as "slot management",
while NSSToken handles actual token operations.</li>
<li>Others?</li>
</ol>
<li>Session management. &nbsp;Tokens needs a threadsafe session handle
to perform operations. &nbsp;CryptoContexts are meant to provide such sessions,
but other objects will need access to token functions as well (examples:
the TrustDomain_Find functions, _Login, _Logout, and others that do not exist
such as NSSToken_ChangePassword). &nbsp;For those functions, the token could
maintain a default session. &nbsp;Thus all NSSToken API functions would take
sessionOpt as an argument. &nbsp;If the caller is going to provide a session,
it sends an NSSSession there, otherwise it sends NULL and the default session
is utilized.<br>
</li>
</ol>
Proposed:<br>
NSSSession<br>
Wraps a Cryptoki session. &nbsp;Created from a slot. &nbsp;Used to manage
sessions for crypto contexts. &nbsp;Has a lock field, which locks the session
if the slot is not threadsafe.<br>
<br>
<hr width="100%" size="2" align="Left"><br>
<h3><a name="pki"></a>
PKI</a>
</h3>
The NSS PKI library.<br>
<br>
<br>
<ol>
<li>The API leaves open the possibility of NSSCertificate meaning various
certificate types, not just X.509. &nbsp;The way to keep open this possibility
is to keep only generally useful information in the NSSCertificate type.
&nbsp;Examples would be the certificate encoding, label, trust (obtained
from cryptoki calls), an email address, etc. &nbsp;Some type of generic
reference should be kept to the decoded certificate, which would then be
accessed by a type-specific API (e.g., NSSX509_GetSubjectName).</li>
</ol>
<br>
<br>
<ol>
<li>Should this be a typedef of NSSCertificate?&nbsp; This implies that
any function that requires an NSSUserCertificate would fail when called
with a certificate lacking a private key. </li>
</ol>
<br>
<br>
<br>
<br>
A trust domain is "the field in which certificates may
be validated." &nbsp;It is a collection of modules capable of performing
cryptographic operations and storing certs and keys. &nbsp;This collection
is managed by NSS in a manner opaque to the consumer. &nbsp;The slots
will have various orderings determining which has preference for a
given operation. &nbsp;For example, the trust domain may order the storage
of user certificates one way, and the storage of email certificates in
another way [is that a good example?].<br>
<br>
<ol>
<li> How will ordering work? &nbsp;We already have the suggestion
that there be two kinds of ordering: storage and search. &nbsp;How
will they be constructed/managed? &nbsp;Do we want to expose access
to a token that overrides this ordering (i.e., the download of updated
root certs may need to override storage order)</li>
<li>How are certs cached? &nbsp;Nelson wonders what it means to Stan
when a cert does not live on a token yet. &nbsp;Bob, Terry, and I discussed
this. &nbsp;My conclusion is that there should be a type, separate
from NSSCertificate, that holds the decoded cert parts (e.g., NSSX509Certificate,
or to avoid confusion, NSSX509DecodedParts). &nbsp;NSSCertificate would
keep a handle to this type, so that it only needs to decode the cert
once. &nbsp;The NSSTrustDomain would keep a hash table of cached certs,
some of which may not live on a token yet (i.e., they are only NSSX509DecodedParts).
&nbsp;This cache could be accessed in the same way the temp db was,
and when the cert is ready to be moved onto a token a call to NSSTrustDomain_ImportCertificate
is made. &nbsp;Note that this is essentially the same as CERT_TempCertToPerm.</li>
<ul>
<li>The hashtable in lib/base (copied from ckfw/hash.c) uses the identity
hash. &nbsp;Therefore, in a hash of certificates, the key is the certificate
pointer itself. &nbsp;One possibility is to store the decoded cert (NSSX509DecodedParts
above) as the value in the {key, value} pair. &nbsp;When a cert is decoded,
the cert pointer and decoding pointer are added to the hash. &nbsp;Subsequent
lookups have access to one or both of these pointers. &nbsp;This keeps NSSCertificate
separate from its decoding, while providing a way to locate it.</li>
</ul>
<li>The API is designed to keep token details hidden from the user. &nbsp;However,
it has already been realized that PSM and CMS may need special access to
tokens. &nbsp;Is this part of the TrustDomain API, or should PSM and CMS
be allowed to use "friend" headers from the Token API?</li>
<li>Do we want to allow traversal via NSSTrustDomain_TraverseXXXX?<br>
</li>
</ol>
NSSCryptoContext</a>
<br>
Analgous to a Cryptoki session. &nbsp;Manages session objects only.<br>
<br>
<br>
<br>
<ol>
comments</a>
.</li>
</ol>
<br>
NSSAlgorithmAndParameters</a>
<br>
<ol>
comments</a>
. &nbsp;The old NSS code had various types related to algorithms
running around in it. &nbsp;We had SECOidTag, SECAlgorithmID, SECItem's
for parameters, CK_MECHANISM for cryptoki, etc. &nbsp;This type should
be able to encapsulate all of those.</li>
</ol>
<br>
<br>
<br>
<br>
<hr width="100%" size="2"><br>
<br>
A diagram to suggest a possible TrustDomain architecture.<br>
<br>
<img src="./standiag.png" alt="Trust Domain Diagram" width="748" height="367">
<br>
<hr width="100%" size="2" align="Left"><br>
<h3><a name="pki1"></a>
PKI1</a>
</h3>
<br>
<br>
<br>
<br>
<br>
<br>
NSSNameChoice<br>
NSSGeneralName<br>
NSSGeneralNameChoice<br>
NSSOtherName<br>
NSSRFC822Name<br>
NSSDNSName<br>
NSSX400Address<br>
NSSEdiParityAddress<br>
NSSURI<br>
NSSIPAddress<br>
NSSRegisteredID<br>
NSSGeneralNameSeq<br>
nssAttributeTypeAliasTable</a>
<br>
<br>
<br>
<hr width="100%" size="2" align="Left"><br>
<h3><a name="pkix"></a>
PKIX&nbsp;</a>
</h3>
There is a plethora of PKIX related types here.<br>
<br>
<hr width="100%" size="2" align="Left"><br>
<h3><a name="build"></a>
Building Stan</h3>
<br>
From nss/lib, run "make BUILD_STAN=1"<br>
<br>
<hr width="100%" size="2" align="Left"><br>
<h3><a name="test"></a>
Testing Stan</h3>
A&nbsp;new command line tool, pkiutil, has been created to use only
the Stan API. &nbsp;It depends on a new library, cmdlib, meant to replace
the old secutil library. &nbsp;The old library had code used by products
that needed to be integrated into the main library codebase somehow. &nbsp;The
goal of the new cmdlib is to have functionality needed strictly for NSS
tools.<br>
<br>
How to build:<br>
<ol>
<li>cd nss/cmd/cmdlib; make</li>
<li>cd ../pkiutil; make</li>
</ol>
pkiutil will give detailed help with either "pkiutil -?" or "pkiutil
--help".<br>
<br>
So far, the only available test is to list certs on the builtins token.
&nbsp;Copy "libnssckbi.so" (or whatever it is) to cmd/pkiutil. &nbsp;Then
run "pkiutil -L" or "pkiutil --list". &nbsp;The list of certificate nicknames
should be displayed.<br>
<br>
<br>
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