Adding upstream version 6.1.22-dfsg.upstream/6.1.22-dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2877 insertions, 0 deletions

diff --git a/src/VBox/Runtime/common/crypto/x509-certpaths.cpp b/src/VBox/Runtime/common/crypto/x509-certpaths.cpp
new file mode 100644
index 00000000..798da4b3
--- /dev/null
+++ b/src/VBox/Runtime/common/crypto/x509-certpaths.cpp
@@ -0,0 +1,2877 @@
+/* $Id: x509-certpaths.cpp $ */
+/** @file
+ * IPRT - Crypto - X.509, Simple Certificate Path Builder & Validator.
+ */
+
+/*
+ * Copyright (C) 2006-2020 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+ * VirtualBox OSE distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#define LOG_GROUP RTLOGGROUP_CRYPTO
+#include "internal/iprt.h"
+#include <iprt/crypto/x509.h>
+
+#include <iprt/asm.h>
+#include <iprt/ctype.h>
+#include <iprt/err.h>
+#include <iprt/mem.h>
+#include <iprt/string.h>
+#include <iprt/list.h>
+#include <iprt/log.h>
+#include <iprt/time.h>
+#include <iprt/crypto/applecodesign.h> /* critical extension OIDs */
+#include <iprt/crypto/pkcs7.h> /* PCRTCRPKCS7SETOFCERTS */
+#include <iprt/crypto/store.h>
+
+#include "x509-internal.h"
+
+
+/*********************************************************************************************************************************
+*   Structures and Typedefs                                                                                                      *
+*********************************************************************************************************************************/
+/**
+ * X.509 certificate path node.
+ */
+typedef struct RTCRX509CERTPATHNODE
+{
+    /** Sibling list entry. */
+    RTLISTNODE                      SiblingEntry;
+    /** List of children or leaf list entry. */
+    RTLISTANCHOR                    ChildListOrLeafEntry;
+    /** Pointer to the parent node.  NULL for root. */
+    struct RTCRX509CERTPATHNODE    *pParent;
+
+    /** The distance between this node and the target.  */
+    uint32_t                        uDepth : 8;
+    /** Indicates the source of this certificate.  */
+    uint32_t                        uSrc : 3;
+    /** Set if this is a leaf node. */
+    uint32_t                        fLeaf : 1;
+    /** Makes sure it's a 32-bit bitfield. */
+    uint32_t                        uReserved : 20;
+
+    /** Leaf only: The result of the last path vertification. */
+    int                             rcVerify;
+
+    /** Pointer to the certificate.  This can be NULL only for trust anchors. */
+    PCRTCRX509CERTIFICATE           pCert;
+
+    /** If the certificate or trust anchor was obtained from a store, this is the
+     * associated certificate context (referenced of course).  This is used to
+     * access the trust anchor information, if present.
+     *
+     * (If this is NULL it's from a certificate array or some such given directly to
+     * the path building code.  It's assumed the caller doesn't free these until the
+     * path validation/whatever is done with and the paths destroyed.) */
+    PCRTCRCERTCTX                   pCertCtx;
+} RTCRX509CERTPATHNODE;
+/** Pointer to a X.509 path node. */
+typedef RTCRX509CERTPATHNODE *PRTCRX509CERTPATHNODE;
+
+/** @name RTCRX509CERTPATHNODE::uSrc values.
+ * The trusted and untrusted sources ordered in priority order, where higher
+ * number means high priority in case of duplicates.
+ * @{ */
+#define RTCRX509CERTPATHNODE_SRC_NONE               0
+#define RTCRX509CERTPATHNODE_SRC_TARGET             1
+#define RTCRX509CERTPATHNODE_SRC_UNTRUSTED_SET      2
+#define RTCRX509CERTPATHNODE_SRC_UNTRUSTED_ARRAY    3
+#define RTCRX509CERTPATHNODE_SRC_UNTRUSTED_STORE    4
+#define RTCRX509CERTPATHNODE_SRC_TRUSTED_STORE      5
+#define RTCRX509CERTPATHNODE_SRC_TRUSTED_CERT       6
+#define RTCRX509CERTPATHNODE_SRC_IS_TRUSTED(uSrc)   ((uSrc) >= RTCRX509CERTPATHNODE_SRC_TRUSTED_STORE)
+/** @} */
+
+
+/**
+ * Policy tree node.
+ */
+typedef struct RTCRX509CERTPATHSPOLICYNODE
+{
+    /** Sibling list entry. */
+    RTLISTNODE                      SiblingEntry;
+    /** Tree depth list entry. */
+    RTLISTNODE                      DepthEntry;
+    /** List of children or leaf list entry. */
+    RTLISTANCHOR                    ChildList;
+    /** Pointer to the parent. */
+    struct RTCRX509CERTPATHSPOLICYNODE *pParent;
+
+    /** The policy object ID. */
+    PCRTASN1OBJID                   pValidPolicy;
+
+    /** Optional sequence of policy qualifiers. */
+    PCRTCRX509POLICYQUALIFIERINFOS  pPolicyQualifiers;
+
+    /** The first policy ID in the exepcted policy set. */
+    PCRTASN1OBJID                   pExpectedPolicyFirst;
+    /** Set if we've already mapped pExpectedPolicyFirst. */
+    bool                            fAlreadyMapped;
+    /** Number of additional items in the expected policy set. */
+    uint32_t                        cMoreExpectedPolicySet;
+    /** Additional items in the expected policy set.  */
+    PCRTASN1OBJID                  *papMoreExpectedPolicySet;
+} RTCRX509CERTPATHSPOLICYNODE;
+/** Pointer to a policy tree node. */
+typedef RTCRX509CERTPATHSPOLICYNODE *PRTCRX509CERTPATHSPOLICYNODE;
+
+
+/**
+ * Path builder and validator instance.
+ *
+ * The path builder creates a tree of certificates by forward searching from the
+ * end-entity towards a trusted source.  The leaf nodes are inserted into list
+ * ordered by the source of the leaf certificate and the path length (i.e. tree
+ * depth).
+ *
+ * The path validator works the tree from the leaf end and validates each
+ * potential path found by the builder.  It is generally happy with one working
+ * path, but may be told to verify all of them.
+ */
+typedef struct RTCRX509CERTPATHSINT
+{
+    /** Magic number. */
+    uint32_t                        u32Magic;
+    /** Reference counter. */
+    uint32_t volatile               cRefs;
+
+    /** @name Input
+     * @{ */
+    /** The target certificate (end entity) to build a trusted path for. */
+    PCRTCRX509CERTIFICATE           pTarget;
+
+    /** Lone trusted certificate.  */
+    PCRTCRX509CERTIFICATE           pTrustedCert;
+    /** Store of trusted certificates. */
+    RTCRSTORE                       hTrustedStore;
+
+    /** Store of untrusted certificates. */
+    RTCRSTORE                       hUntrustedStore;
+    /** Array of untrusted certificates, typically from the protocol. */
+    PCRTCRX509CERTIFICATE           paUntrustedCerts;
+    /** Number of entries in paUntrusted. */
+    uint32_t                        cUntrustedCerts;
+    /** Set of untrusted PKCS \#7 / CMS certificatess. */
+    PCRTCRPKCS7SETOFCERTS           pUntrustedCertsSet;
+
+    /** UTC time we're going to validate the path at, requires
+     *  RTCRX509CERTPATHSINT_F_VALID_TIME to be set. */
+    RTTIMESPEC                      ValidTime;
+    /** Number of policy OIDs in the user initial policy set, 0 means anyPolicy. */
+    uint32_t                        cInitialUserPolicySet;
+    /** The user initial policy set.  As with all other user provided data, we
+     * assume it's immutable and remains valid for the usage period of the path
+     * builder & validator. */
+    PCRTASN1OBJID                  *papInitialUserPolicySet;
+    /** Number of certificates before the user wants an explicit policy result.
+     * Set to UINT32_MAX no explicit policy restriction required by the user. */
+    uint32_t                        cInitialExplicitPolicy;
+    /** Number of certificates before the user wants policy mapping to be
+     * inhibited.  Set to UINT32_MAX if no initial policy mapping inhibition
+     * desired by the user. */
+    uint32_t                        cInitialPolicyMappingInhibit;
+    /** Number of certificates before the user wants the anyPolicy to be rejected.
+     * Set to UINT32_MAX no explicit policy restriction required by the user. */
+    uint32_t                        cInitialInhibitAnyPolicy;
+    /** Initial name restriction: Permitted subtrees.  */
+    PCRTCRX509GENERALSUBTREES       pInitialPermittedSubtrees;
+    /** Initial name restriction: Excluded subtrees.  */
+    PCRTCRX509GENERALSUBTREES       pInitialExcludedSubtrees;
+
+    /** Flags RTCRX509CERTPATHSINT_F_XXX. */
+    uint32_t                        fFlags;
+    /** @} */
+
+    /** Sticky status for remembering allocation errors and the like.  */
+    int32_t                         rc;
+    /** Where to store extended error info (optional). */
+    PRTERRINFO                      pErrInfo;
+
+    /** @name Path Builder Output
+     * @{  */
+    /** Pointer to the root of the tree.  This will always be non-NULL after path
+     *  building and thus can be reliably used to tell if path building has taken
+     *  place or not. */
+    PRTCRX509CERTPATHNODE           pRoot;
+    /** List of working leaf tree nodes. */
+    RTLISTANCHOR                    LeafList;
+    /** The number of paths (leafs). */
+    uint32_t                        cPaths;
+    /** @} */
+
+    /** Path Validator State. */
+    struct
+    {
+        /** Number of nodes in the certificate path we're validating (aka 'n'). */
+        uint32_t                        cNodes;
+        /** The current node (0 being the trust anchor). */
+        uint32_t                        iNode;
+
+        /** The root node of the valid policy tree. */
+        PRTCRX509CERTPATHSPOLICYNODE    pValidPolicyTree;
+        /** An array of length cNodes + 1 which tracks all nodes at the given (index)
+         *  tree depth via the RTCRX509CERTPATHSPOLICYNODE::DepthEntry member. */
+        PRTLISTANCHOR                   paValidPolicyDepthLists;
+
+        /** Number of entries in paPermittedSubtrees (name constraints).
+         * If zero, no permitted name constrains currently in effect.  */
+        uint32_t                        cPermittedSubtrees;
+        /** The allocated size of papExcludedSubtrees */
+        uint32_t                        cPermittedSubtreesAlloc;
+        /** Array of permitted subtrees we've collected so far (name constraints). */
+        PCRTCRX509GENERALSUBTREE       *papPermittedSubtrees;
+        /** Set if we end up with an empty set after calculating a name constraints
+         * union.  */
+        bool                            fNoPermittedSubtrees;
+
+        /** Number of entries in paExcludedSubtrees (name constraints).
+         * If zero, no excluded name constrains currently in effect.  */
+        uint32_t                        cExcludedSubtrees;
+        /** Array of excluded subtrees we've collected so far (name constraints). */
+        PCRTCRX509GENERALSUBTREES      *papExcludedSubtrees;
+
+        /** Number of non-self-issued certificates to be processed before a non-NULL
+         * paValidPolicyTree is required. */
+        uint32_t                        cExplicitPolicy;
+        /** Number of non-self-issued certificates to be processed we stop processing
+         * policy mapping extensions. */
+        uint32_t                        cInhibitPolicyMapping;
+        /** Number of non-self-issued certificates to be processed before a the
+         * anyPolicy is rejected. */
+        uint32_t                        cInhibitAnyPolicy;
+        /** Number of non-self-issued certificates we're allowed to process. */
+        uint32_t                        cMaxPathLength;
+
+        /** The working issuer name. */
+        PCRTCRX509NAME                  pWorkingIssuer;
+        /** The working public key algorithm ID. */
+        PCRTASN1OBJID                   pWorkingPublicKeyAlgorithm;
+        /** The working public key algorithm parameters. */
+        PCRTASN1DYNTYPE                 pWorkingPublicKeyParameters;
+        /** A bit string containing the public key. */
+        PCRTASN1BITSTRING               pWorkingPublicKey;
+    } v;
+
+    /** An object identifier initialized to anyPolicy. */
+    RTASN1OBJID                         AnyPolicyObjId;
+
+    /** Temporary scratch space. */
+    char                                szTmp[1024];
+} RTCRX509CERTPATHSINT;
+typedef RTCRX509CERTPATHSINT *PRTCRX509CERTPATHSINT;
+
+/** Magic value for RTCRX509CERTPATHSINT::u32Magic (Bruce Schneier). */
+#define RTCRX509CERTPATHSINT_MAGIC                          UINT32_C(0x19630115)
+
+/** @name RTCRX509CERTPATHSINT_F_XXX - Certificate path build flags.
+ * @{ */
+#define RTCRX509CERTPATHSINT_F_VALID_TIME                    RT_BIT_32(0)
+#define RTCRX509CERTPATHSINT_F_ELIMINATE_UNTRUSTED_PATHS     RT_BIT_32(1)
+#define RTCRX509CERTPATHSINT_F_VALID_MASK                    UINT32_C(0x00000003)
+/** @} */
+
+
+/*********************************************************************************************************************************
+*   Internal Functions                                                                                                           *
+*********************************************************************************************************************************/
+static void rtCrX509CertPathsDestroyTree(PRTCRX509CERTPATHSINT pThis);
+static void rtCrX509CpvCleanup(PRTCRX509CERTPATHSINT pThis);
+
+
+/** @name Path Builder and Validator Config APIs
+ * @{
+ */
+
+RTDECL(int) RTCrX509CertPathsCreate(PRTCRX509CERTPATHS phCertPaths, PCRTCRX509CERTIFICATE pTarget)
+{
+    AssertPtrReturn(phCertPaths, VERR_INVALID_POINTER);
+
+    PRTCRX509CERTPATHSINT pThis = (PRTCRX509CERTPATHSINT)RTMemAllocZ(sizeof(*pThis));
+    if (pThis)
+    {
+        int rc = RTAsn1ObjId_InitFromString(&pThis->AnyPolicyObjId, RTCRX509_ID_CE_CP_ANY_POLICY_OID, &g_RTAsn1DefaultAllocator);
+        if (RT_SUCCESS(rc))
+        {
+            pThis->u32Magic                     = RTCRX509CERTPATHSINT_MAGIC;
+            pThis->cRefs                        = 1;
+            pThis->pTarget                      = pTarget;
+            pThis->hTrustedStore                = NIL_RTCRSTORE;
+            pThis->hUntrustedStore              = NIL_RTCRSTORE;
+            pThis->cInitialExplicitPolicy       = UINT32_MAX;
+            pThis->cInitialPolicyMappingInhibit = UINT32_MAX;
+            pThis->cInitialInhibitAnyPolicy     = UINT32_MAX;
+            pThis->rc                           = VINF_SUCCESS;
+            RTListInit(&pThis->LeafList);
+            *phCertPaths = pThis;
+            return VINF_SUCCESS;
+        }
+        return rc;
+    }
+    return VERR_NO_MEMORY;
+}
+
+
+RTDECL(uint32_t) RTCrX509CertPathsRetain(RTCRX509CERTPATHS hCertPaths)
+{
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, UINT32_MAX);
+
+    uint32_t cRefs = ASMAtomicIncU32(&pThis->cRefs);
+    Assert(cRefs > 0 && cRefs < 64);
+    return cRefs;
+}
+
+
+RTDECL(uint32_t) RTCrX509CertPathsRelease(RTCRX509CERTPATHS hCertPaths)
+{
+    uint32_t cRefs;
+    if (hCertPaths != NIL_RTCRX509CERTPATHS)
+    {
+        PRTCRX509CERTPATHSINT pThis = hCertPaths;
+        AssertPtrReturn(pThis, UINT32_MAX);
+        AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, UINT32_MAX);
+
+        cRefs = ASMAtomicDecU32(&pThis->cRefs);
+        Assert(cRefs < 64);
+        if (!cRefs)
+        {
+            /*
+             * No more references, destroy the whole thing.
+             */
+            ASMAtomicWriteU32(&pThis->u32Magic, ~RTCRX509CERTPATHSINT_MAGIC);
+
+            /* config */
+            pThis->pTarget                      = NULL; /* Referencing user memory. */
+            pThis->pTrustedCert                 = NULL; /* Referencing user memory. */
+            RTCrStoreRelease(pThis->hTrustedStore);
+            pThis->hTrustedStore                = NIL_RTCRSTORE;
+            RTCrStoreRelease(pThis->hUntrustedStore);
+            pThis->hUntrustedStore              = NIL_RTCRSTORE;
+            pThis->paUntrustedCerts             = NULL; /* Referencing user memory. */
+            pThis->pUntrustedCertsSet           = NULL; /* Referencing user memory. */
+            pThis->papInitialUserPolicySet      = NULL; /* Referencing user memory. */
+            pThis->pInitialPermittedSubtrees    = NULL; /* Referencing user memory. */
+            pThis->pInitialExcludedSubtrees     = NULL; /* Referencing user memory. */
+
+            /* builder */
+            rtCrX509CertPathsDestroyTree(pThis);
+
+            /* validator */
+            rtCrX509CpvCleanup(pThis);
+
+            /* misc */
+            RTAsn1VtDelete(&pThis->AnyPolicyObjId.Asn1Core);
+
+            /* Finally, the instance itself. */
+            RTMemFree(pThis);
+        }
+    }
+    else
+        cRefs = 0;
+    return cRefs;
+}
+
+
+
+RTDECL(int) RTCrX509CertPathsSetTrustedStore(RTCRX509CERTPATHS hCertPaths, RTCRSTORE hTrustedStore)
+{
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->pRoot == NULL, VERR_WRONG_ORDER);
+
+    if (pThis->hTrustedStore != NIL_RTCRSTORE)
+    {
+        RTCrStoreRelease(pThis->hTrustedStore);
+        pThis->hTrustedStore = NIL_RTCRSTORE;
+    }
+    if (hTrustedStore != NIL_RTCRSTORE)
+    {
+        AssertReturn(RTCrStoreRetain(hTrustedStore) != UINT32_MAX, VERR_INVALID_HANDLE);
+        pThis->hTrustedStore = hTrustedStore;
+    }
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int) RTCrX509CertPathsSetUntrustedStore(RTCRX509CERTPATHS hCertPaths, RTCRSTORE hUntrustedStore)
+{
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->pRoot == NULL, VERR_WRONG_ORDER);
+
+    if (pThis->hUntrustedStore != NIL_RTCRSTORE)
+    {
+        RTCrStoreRelease(pThis->hUntrustedStore);
+        pThis->hUntrustedStore = NIL_RTCRSTORE;
+    }
+    if (hUntrustedStore != NIL_RTCRSTORE)
+    {
+        AssertReturn(RTCrStoreRetain(hUntrustedStore) != UINT32_MAX, VERR_INVALID_HANDLE);
+        pThis->hUntrustedStore = hUntrustedStore;
+    }
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int) RTCrX509CertPathsSetUntrustedArray(RTCRX509CERTPATHS hCertPaths, PCRTCRX509CERTIFICATE paCerts, uint32_t cCerts)
+{
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+
+    pThis->paUntrustedCerts = paCerts;
+    pThis->cUntrustedCerts  = cCerts;
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int) RTCrX509CertPathsSetUntrustedSet(RTCRX509CERTPATHS hCertPaths, PCRTCRPKCS7SETOFCERTS pSetOfCerts)
+{
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+
+    pThis->pUntrustedCertsSet = pSetOfCerts;
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int) RTCrX509CertPathsSetValidTime(RTCRX509CERTPATHS hCertPaths, PCRTTIME pTime)
+{
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+
+    /* Allow this after building paths, as it's only used during verification. */
+
+    if (pTime)
+    {
+        if (RTTimeImplode(&pThis->ValidTime, pTime))
+            return VERR_INVALID_PARAMETER;
+        pThis->fFlags |= RTCRX509CERTPATHSINT_F_VALID_TIME;
+    }
+    else
+        pThis->fFlags &= ~RTCRX509CERTPATHSINT_F_VALID_TIME;
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int) RTCrX509CertPathsSetValidTimeSpec(RTCRX509CERTPATHS hCertPaths, PCRTTIMESPEC pTimeSpec)
+{
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+
+    /* Allow this after building paths, as it's only used during verification. */
+
+    if (pTimeSpec)
+    {
+        pThis->ValidTime = *pTimeSpec;
+        pThis->fFlags |= RTCRX509CERTPATHSINT_F_VALID_TIME;
+    }
+    else
+        pThis->fFlags &= ~RTCRX509CERTPATHSINT_F_VALID_TIME;
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int) RTCrX509CertPathsCreateEx(PRTCRX509CERTPATHS phCertPaths, PCRTCRX509CERTIFICATE pTarget, RTCRSTORE hTrustedStore,
+                                      RTCRSTORE hUntrustedStore, PCRTCRX509CERTIFICATE paUntrustedCerts, uint32_t cUntrustedCerts,
+                                      PCRTTIMESPEC pValidTime)
+{
+    int rc = RTCrX509CertPathsCreate(phCertPaths, pTarget);
+    if (RT_SUCCESS(rc))
+    {
+        PRTCRX509CERTPATHSINT pThis = *phCertPaths;
+
+        rc = RTCrX509CertPathsSetTrustedStore(pThis, hTrustedStore);
+        if (RT_SUCCESS(rc))
+        {
+            rc = RTCrX509CertPathsSetUntrustedStore(pThis, hUntrustedStore);
+            if (RT_SUCCESS(rc))
+            {
+                rc = RTCrX509CertPathsSetUntrustedArray(pThis, paUntrustedCerts, cUntrustedCerts);
+                if (RT_SUCCESS(rc))
+                {
+                    rc = RTCrX509CertPathsSetValidTimeSpec(pThis, pValidTime);
+                    if (RT_SUCCESS(rc))
+                    {
+                        return VINF_SUCCESS;
+                    }
+                }
+                RTCrStoreRelease(pThis->hUntrustedStore);
+            }
+            RTCrStoreRelease(pThis->hTrustedStore);
+        }
+        RTMemFree(pThis);
+        *phCertPaths = NIL_RTCRX509CERTPATHS;
+    }
+    return rc;
+}
+
+/** @} */
+
+
+
+/** @name Path Builder and Validator Common Utility Functions.
+ * @{
+ */
+
+/**
+ * Checks if the certificate is self-issued.
+ *
+ * @returns true / false.
+ * @param   pNode               The path node to check..
+ */
+static bool rtCrX509CertPathsIsSelfIssued(PRTCRX509CERTPATHNODE pNode)
+{
+    return pNode->pCert
+        && RTCrX509Name_MatchByRfc5280(&pNode->pCert->TbsCertificate.Subject, &pNode->pCert->TbsCertificate.Issuer);
+}
+
+/** @}  */
+
+
+
+/** @name Path Builder Functions.
+ * @{
+ */
+
+/**
+ *
+ * @returns
+ * @param   pThis               .
+ */
+static PRTCRX509CERTPATHNODE rtCrX509CertPathsNewNode(PRTCRX509CERTPATHSINT pThis)
+{
+    PRTCRX509CERTPATHNODE pNode = (PRTCRX509CERTPATHNODE)RTMemAllocZ(sizeof(*pNode));
+    if (RT_LIKELY(pNode))
+    {
+        RTListInit(&pNode->SiblingEntry);
+        RTListInit(&pNode->ChildListOrLeafEntry);
+        pNode->rcVerify = VERR_CR_X509_NOT_VERIFIED;
+
+        return pNode;
+    }
+
+    pThis->rc = RTErrInfoSet(pThis->pErrInfo, VERR_NO_MEMORY, "No memory for path node");
+    return NULL;
+}
+
+
+static void rtCrX509CertPathsDestroyNode(PRTCRX509CERTPATHNODE pNode)
+{
+    if (pNode->pCertCtx)
+    {
+        RTCrCertCtxRelease(pNode->pCertCtx);
+        pNode->pCertCtx = NULL;
+    }
+    RT_ZERO(*pNode);
+    RTMemFree(pNode);
+}
+
+
+static void rtCrX509CertPathsAddIssuer(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pParent,
+                                       PCRTCRX509CERTIFICATE pCert, PCRTCRCERTCTX pCertCtx, uint8_t uSrc)
+{
+    /*
+     * Check if we've seen this certificate already in the current path or
+     * among the already gathered issuers.
+     */
+    if (pCert)
+    {
+        /* No duplicate certificates in the path. */
+        PRTCRX509CERTPATHNODE pTmpNode = pParent;
+        while (pTmpNode)
+        {
+            Assert(pTmpNode->pCert);
+            if (   pTmpNode->pCert == pCert
+                || RTCrX509Certificate_Compare(pTmpNode->pCert, pCert) == 0)
+                return;
+            pTmpNode = pTmpNode->pParent;
+        }
+
+        /* No duplicate tree branches. */
+        RTListForEach(&pParent->ChildListOrLeafEntry, pTmpNode, RTCRX509CERTPATHNODE, SiblingEntry)
+        {
+            if (RTCrX509Certificate_Compare(pTmpNode->pCert, pCert) == 0)
+                return;
+        }
+    }
+    else
+        Assert(pCertCtx);
+
+    /*
+     * Reference the context core before making the allocation.
+     */
+    if (pCertCtx)
+        AssertReturnVoidStmt(RTCrCertCtxRetain(pCertCtx) != UINT32_MAX,
+                             pThis->rc = RTErrInfoSetF(pThis->pErrInfo, VERR_CR_X509_CPB_BAD_CERT_CTX,
+                                                       "Bad pCertCtx=%p", pCertCtx));
+
+    /*
+     * We haven't see it, append it as a child.
+     */
+    PRTCRX509CERTPATHNODE pNew = rtCrX509CertPathsNewNode(pThis);
+    if (pNew)
+    {
+        pNew->pParent  = pParent;
+        pNew->pCert    = pCert;
+        pNew->pCertCtx = pCertCtx;
+        pNew->uSrc     = uSrc;
+        pNew->uDepth   = pParent->uDepth + 1;
+        RTListAppend(&pParent->ChildListOrLeafEntry, &pNew->SiblingEntry);
+    }
+    else
+        RTCrCertCtxRelease(pCertCtx);
+}
+
+
+static void rtCrX509CertPathsGetIssuersFromStore(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode,
+                                                 PCRTCRX509NAME pIssuer, RTCRSTORE hStore, uint8_t uSrc)
+{
+    RTCRSTORECERTSEARCH Search;
+    int rc = RTCrStoreCertFindBySubjectOrAltSubjectByRfc5280(hStore, pIssuer, &Search);
+    if (RT_SUCCESS(rc))
+    {
+        PCRTCRCERTCTX pCertCtx;
+        while ((pCertCtx = RTCrStoreCertSearchNext(hStore, &Search)) != NULL)
+        {
+            if (   pCertCtx->pCert
+                || (   RTCRX509CERTPATHNODE_SRC_IS_TRUSTED(uSrc)
+                    && pCertCtx->pTaInfo) )
+                rtCrX509CertPathsAddIssuer(pThis, pNode, pCertCtx->pCert, pCertCtx, uSrc);
+            RTCrCertCtxRelease(pCertCtx);
+        }
+        RTCrStoreCertSearchDestroy(hStore, &Search);
+    }
+}
+
+
+static void rtCrX509CertPathsGetIssuers(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    Assert(RTListIsEmpty(&pNode->ChildListOrLeafEntry));
+    Assert(!pNode->fLeaf);
+    Assert(pNode->pCert);
+
+    /*
+     * Don't recurse infintely.
+     */
+    if (RT_UNLIKELY(pNode->uDepth >= 50))
+        return;
+
+    PCRTCRX509NAME const pIssuer = &pNode->pCert->TbsCertificate.Issuer;
+
+    /*
+     * Trusted certificate.
+     */
+    if (   pThis->pTrustedCert
+        && RTCrX509Certificate_MatchSubjectOrAltSubjectByRfc5280(pThis->pTrustedCert, pIssuer))
+        rtCrX509CertPathsAddIssuer(pThis, pNode, pThis->pTrustedCert, NULL, RTCRX509CERTPATHNODE_SRC_TRUSTED_CERT);
+
+    /*
+     * Trusted certificate store.
+     */
+    if (pThis->hTrustedStore != NIL_RTCRSTORE)
+        rtCrX509CertPathsGetIssuersFromStore(pThis, pNode, pIssuer, pThis->hTrustedStore,
+                                             RTCRX509CERTPATHNODE_SRC_TRUSTED_STORE);
+
+    /*
+     * Untrusted store.
+     */
+    if (pThis->hUntrustedStore != NIL_RTCRSTORE)
+        rtCrX509CertPathsGetIssuersFromStore(pThis, pNode, pIssuer, pThis->hTrustedStore,
+                                             RTCRX509CERTPATHNODE_SRC_UNTRUSTED_STORE);
+
+    /*
+     * Untrusted array.
+     */
+    if (pThis->paUntrustedCerts)
+        for (uint32_t i = 0; i < pThis->cUntrustedCerts; i++)
+            if (RTCrX509Certificate_MatchSubjectOrAltSubjectByRfc5280(&pThis->paUntrustedCerts[i], pIssuer))
+                rtCrX509CertPathsAddIssuer(pThis, pNode, &pThis->paUntrustedCerts[i], NULL,
+                                           RTCRX509CERTPATHNODE_SRC_UNTRUSTED_ARRAY);
+
+    /** @todo Rainy day: Should abstract the untrusted array and set so we don't get
+     *        unnecessary PKCS7/CMS header dependencies. */
+
+    /*
+     * Untrusted set.
+     */
+    if (pThis->pUntrustedCertsSet)
+    {
+        uint32_t const        cCerts   = pThis->pUntrustedCertsSet->cItems;
+        PRTCRPKCS7CERT const *papCerts = pThis->pUntrustedCertsSet->papItems;
+        for (uint32_t i = 0; i < cCerts; i++)
+        {
+            PCRTCRPKCS7CERT pCert = papCerts[i];
+            if (   pCert->enmChoice == RTCRPKCS7CERTCHOICE_X509
+                && RTCrX509Certificate_MatchSubjectOrAltSubjectByRfc5280(pCert->u.pX509Cert, pIssuer))
+                rtCrX509CertPathsAddIssuer(pThis, pNode, pCert->u.pX509Cert, NULL, RTCRX509CERTPATHNODE_SRC_UNTRUSTED_SET);
+        }
+    }
+}
+
+
+static PRTCRX509CERTPATHNODE rtCrX509CertPathsGetNextRightUp(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    for (;;)
+    {
+        /* The root node has no siblings. */
+        PRTCRX509CERTPATHNODE pParent = pNode->pParent;
+        if (!pNode->pParent)
+            return NULL;
+
+        /* Try go to the right. */
+        PRTCRX509CERTPATHNODE pNext = RTListGetNext(&pParent->ChildListOrLeafEntry, pNode, RTCRX509CERTPATHNODE, SiblingEntry);
+        if (pNext)
+            return pNext;
+
+        /* Up. */
+        pNode = pParent;
+    }
+
+    RT_NOREF_PV(pThis);
+}
+
+
+static PRTCRX509CERTPATHNODE rtCrX509CertPathsEliminatePath(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    for (;;)
+    {
+        Assert(RTListIsEmpty(&pNode->ChildListOrLeafEntry));
+
+        /* Don't remove the root node. */
+        PRTCRX509CERTPATHNODE pParent = pNode->pParent;
+        if (!pParent)
+            return NULL;
+
+        /* Before removing and deleting the node check if there is sibling
+           right to it that we should continue processing from. */
+        PRTCRX509CERTPATHNODE pNext = RTListGetNext(&pParent->ChildListOrLeafEntry, pNode, RTCRX509CERTPATHNODE, SiblingEntry);
+        RTListNodeRemove(&pNode->SiblingEntry);
+        rtCrX509CertPathsDestroyNode(pNode);
+
+        if (pNext)
+            return pNext;
+
+        /* If the parent node cannot be removed, do a normal get-next-rigth-up
+           to find the continuation point for the tree loop. */
+        if (!RTListIsEmpty(&pParent->ChildListOrLeafEntry))
+            return rtCrX509CertPathsGetNextRightUp(pThis, pParent);
+
+        pNode = pParent;
+    }
+}
+
+
+/**
+ * Destroys the whole path tree.
+ *
+ * @param   pThis       The path builder and verifier instance.
+ */
+static void rtCrX509CertPathsDestroyTree(PRTCRX509CERTPATHSINT pThis)
+{
+    PRTCRX509CERTPATHNODE pNode, pNextLeaf;
+    RTListForEachSafe(&pThis->LeafList, pNode, pNextLeaf, RTCRX509CERTPATHNODE, ChildListOrLeafEntry)
+    {
+        RTListNodeRemove(&pNode->ChildListOrLeafEntry);
+        RTListInit(&pNode->ChildListOrLeafEntry);
+
+        for (;;)
+        {
+            PRTCRX509CERTPATHNODE pParent = pNode->pParent;
+
+            RTListNodeRemove(&pNode->SiblingEntry);
+            rtCrX509CertPathsDestroyNode(pNode);
+
+            if (!pParent)
+            {
+                pThis->pRoot = NULL;
+                break;
+            }
+
+            if (!RTListIsEmpty(&pParent->ChildListOrLeafEntry))
+                break;
+
+            pNode = pParent;
+        }
+    }
+    Assert(!pThis->pRoot);
+}
+
+
+/**
+ * Adds a leaf node.
+ *
+ * This should normally be a trusted certificate, but the caller can also
+ * request the incomplete paths, in which case this will be an untrusted
+ * certificate.
+ *
+ * @returns Pointer to the next node in the tree to process.
+ * @param   pThis               The path builder instance.
+ * @param   pNode               The leaf node.
+ */
+static PRTCRX509CERTPATHNODE rtCrX509CertPathsAddLeaf(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    pNode->fLeaf = true;
+
+    /*
+     * Priority insert by source and depth.
+     */
+    PRTCRX509CERTPATHNODE pCurLeaf;
+    RTListForEach(&pThis->LeafList, pCurLeaf, RTCRX509CERTPATHNODE, ChildListOrLeafEntry)
+    {
+        if (   pNode->uSrc > pCurLeaf->uSrc
+            || (   pNode->uSrc == pCurLeaf->uSrc
+                && pNode->uDepth < pCurLeaf->uDepth) )
+        {
+            RTListNodeInsertBefore(&pCurLeaf->ChildListOrLeafEntry, &pNode->ChildListOrLeafEntry);
+            pThis->cPaths++;
+            return rtCrX509CertPathsGetNextRightUp(pThis, pNode);
+        }
+    }
+
+    RTListAppend(&pThis->LeafList, &pNode->ChildListOrLeafEntry);
+    pThis->cPaths++;
+    return rtCrX509CertPathsGetNextRightUp(pThis, pNode);
+}
+
+
+
+RTDECL(int) RTCrX509CertPathsBuild(RTCRX509CERTPATHS hCertPaths, PRTERRINFO pErrInfo)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertReturn(!(pThis->fFlags & ~RTCRX509CERTPATHSINT_F_VALID_MASK), VERR_INVALID_PARAMETER);
+    AssertReturn(   (pThis->paUntrustedCerts == NULL && pThis->cUntrustedCerts == 0)
+                 || (pThis->paUntrustedCerts != NULL && pThis->cUntrustedCerts > 0),
+                 VERR_INVALID_PARAMETER);
+    AssertReturn(RTListIsEmpty(&pThis->LeafList), VERR_INVALID_PARAMETER);
+    AssertReturn(pThis->pRoot == NULL, VERR_INVALID_PARAMETER);
+    AssertReturn(pThis->rc == VINF_SUCCESS, pThis->rc);
+    AssertPtrReturn(pThis->pTarget, VERR_INVALID_PARAMETER);
+    Assert(RT_SUCCESS(RTCrX509Certificate_CheckSanity(pThis->pTarget, 0, NULL, NULL)));
+
+    /*
+     * Set up the target.
+     */
+    PRTCRX509CERTPATHNODE pCur;
+    pThis->pRoot = pCur = rtCrX509CertPathsNewNode(pThis);
+    if (pThis->pRoot)
+    {
+        pCur->pCert  = pThis->pTarget;
+        pCur->uDepth = 0;
+        pCur->uSrc   = RTCRX509CERTPATHNODE_SRC_TARGET;
+
+        pThis->pErrInfo = pErrInfo;
+
+        /*
+         * The tree construction loop.
+         * Walks down, up, and right as the tree is constructed.
+         */
+        do
+        {
+            /*
+             * Check for the two leaf cases first.
+             */
+            if (RTCRX509CERTPATHNODE_SRC_IS_TRUSTED(pCur->uSrc))
+                pCur = rtCrX509CertPathsAddLeaf(pThis, pCur);
+#if 0 /* This isn't right.*/
+            else if (rtCrX509CertPathsIsSelfIssued(pCur))
+            {
+                if (pThis->fFlags & RTCRX509CERTPATHSINT_F_ELIMINATE_UNTRUSTED_PATHS)
+                    pCur = rtCrX509CertPathsEliminatePath(pThis, pCur);
+                else
+                    pCur = rtCrX509CertPathsAddLeaf(pThis, pCur);
+            }
+#endif
+            /*
+             * Not a leaf, find all potential issuers and decend into these.
+             */
+            else
+            {
+                rtCrX509CertPathsGetIssuers(pThis, pCur);
+                if (RT_FAILURE(pThis->rc))
+                    break;
+
+                if (!RTListIsEmpty(&pCur->ChildListOrLeafEntry))
+                    pCur = RTListGetFirst(&pCur->ChildListOrLeafEntry, RTCRX509CERTPATHNODE, SiblingEntry);
+                else if (pThis->fFlags & RTCRX509CERTPATHSINT_F_ELIMINATE_UNTRUSTED_PATHS)
+                    pCur = rtCrX509CertPathsEliminatePath(pThis, pCur);
+                else
+                    pCur = rtCrX509CertPathsAddLeaf(pThis, pCur);
+            }
+            if (pCur)
+                Log2(("RTCrX509CertPathsBuild: pCur=%p fLeaf=%d pParent=%p pNext=%p pPrev=%p\n",
+                      pCur, pCur->fLeaf, pCur->pParent,
+                      pCur->pParent ? RTListGetNext(&pCur->pParent->ChildListOrLeafEntry, pCur, RTCRX509CERTPATHNODE, SiblingEntry) : NULL,
+                      pCur->pParent ? RTListGetPrev(&pCur->pParent->ChildListOrLeafEntry, pCur, RTCRX509CERTPATHNODE, SiblingEntry) : NULL));
+        } while (pCur);
+
+        pThis->pErrInfo = NULL;
+        if (RT_SUCCESS(pThis->rc))
+            return VINF_SUCCESS;
+    }
+    else
+        Assert(RT_FAILURE_NP(pThis->rc));
+    return pThis->rc;
+}
+
+
+/**
+ * Looks up path by leaf/path index.
+ *
+ * @returns Pointer to the leaf node of the path.
+ * @param   pThis           The path builder & validator instance.
+ * @param   iPath           The oridnal of the path to get.
+ */
+static PRTCRX509CERTPATHNODE rtCrX509CertPathsGetLeafByIndex(PRTCRX509CERTPATHSINT pThis, uint32_t iPath)
+{
+    Assert(iPath < pThis->cPaths);
+
+    uint32_t                iCurPath = 0;
+    PRTCRX509CERTPATHNODE   pCurLeaf;
+    RTListForEach(&pThis->LeafList, pCurLeaf, RTCRX509CERTPATHNODE, ChildListOrLeafEntry)
+    {
+        if (iCurPath == iPath)
+            return pCurLeaf;
+        iCurPath++;
+    }
+
+    AssertFailedReturn(NULL);
+}
+
+
+static void rtDumpPrintf(PFNRTDUMPPRINTFV pfnPrintfV, void *pvUser, const char *pszFormat, ...)
+{
+    va_list va;
+    va_start(va, pszFormat);
+    pfnPrintfV(pvUser, pszFormat, va);
+    va_end(va);
+}
+
+
+static void rtDumpIndent(PFNRTDUMPPRINTFV pfnPrintfV, void *pvUser, uint32_t cchSpaces, const char *pszFormat, ...)
+{
+    static const char s_szSpaces[] = "                          ";
+    while (cchSpaces > 0)
+    {
+        uint32_t cchBurst = RT_MIN(sizeof(s_szSpaces) - 1, cchSpaces);
+        rtDumpPrintf(pfnPrintfV, pvUser, &s_szSpaces[sizeof(s_szSpaces) - cchBurst - 1]);
+        cchSpaces -= cchBurst;
+    }
+
+    va_list va;
+    va_start(va, pszFormat);
+    pfnPrintfV(pvUser, pszFormat, va);
+    va_end(va);
+}
+
+/** @name X.500 attribute types
+ * See RFC-4519 among others.
+ * @{ */
+#define RTCRX500_ID_AT_OBJECT_CLASS_OID                     "2.5.4.0"
+#define RTCRX500_ID_AT_ALIASED_ENTRY_NAME_OID               "2.5.4.1"
+#define RTCRX500_ID_AT_KNOWLDGEINFORMATION_OID              "2.5.4.2"
+#define RTCRX500_ID_AT_COMMON_NAME_OID                      "2.5.4.3"
+#define RTCRX500_ID_AT_SURNAME_OID                          "2.5.4.4"
+#define RTCRX500_ID_AT_SERIAL_NUMBER_OID                    "2.5.4.5"
+#define RTCRX500_ID_AT_COUNTRY_NAME_OID                     "2.5.4.6"
+#define RTCRX500_ID_AT_LOCALITY_NAME_OID                    "2.5.4.7"
+#define RTCRX500_ID_AT_STATE_OR_PROVINCE_NAME_OID           "2.5.4.8"
+#define RTCRX500_ID_AT_STREET_ADDRESS_OID                   "2.5.4.9"
+#define RTCRX500_ID_AT_ORGANIZATION_NAME_OID                "2.5.4.10"
+#define RTCRX500_ID_AT_ORGANIZATION_UNIT_NAME_OID           "2.5.4.11"
+#define RTCRX500_ID_AT_TITLE_OID                            "2.5.4.12"
+#define RTCRX500_ID_AT_DESCRIPTION_OID                      "2.5.4.13"
+#define RTCRX500_ID_AT_SEARCH_GUIDE_OID                     "2.5.4.14"
+#define RTCRX500_ID_AT_BUSINESS_CATEGORY_OID                "2.5.4.15"
+#define RTCRX500_ID_AT_POSTAL_ADDRESS_OID                   "2.5.4.16"
+#define RTCRX500_ID_AT_POSTAL_CODE_OID                      "2.5.4.17"
+#define RTCRX500_ID_AT_POST_OFFICE_BOX_OID                  "2.5.4.18"
+#define RTCRX500_ID_AT_PHYSICAL_DELIVERY_OFFICE_NAME_OID    "2.5.4.19"
+#define RTCRX500_ID_AT_TELEPHONE_NUMBER_OID                 "2.5.4.20"
+#define RTCRX500_ID_AT_TELEX_NUMBER_OID                     "2.5.4.21"
+#define RTCRX500_ID_AT_TELETEX_TERMINAL_IDENTIFIER_OID      "2.5.4.22"
+#define RTCRX500_ID_AT_FACIMILE_TELEPHONE_NUMBER_OID        "2.5.4.23"
+#define RTCRX500_ID_AT_X121_ADDRESS_OID                     "2.5.4.24"
+#define RTCRX500_ID_AT_INTERNATIONAL_ISDN_NUMBER_OID        "2.5.4.25"
+#define RTCRX500_ID_AT_REGISTERED_ADDRESS_OID               "2.5.4.26"
+#define RTCRX500_ID_AT_DESTINATION_INDICATOR_OID            "2.5.4.27"
+#define RTCRX500_ID_AT_PREFERRED_DELIVERY_METHOD_OID        "2.5.4.28"
+#define RTCRX500_ID_AT_PRESENTATION_ADDRESS_OID             "2.5.4.29"
+#define RTCRX500_ID_AT_SUPPORTED_APPLICATION_CONTEXT_OID    "2.5.4.30"
+#define RTCRX500_ID_AT_MEMBER_OID                           "2.5.4.31"
+#define RTCRX500_ID_AT_OWNER_OID                            "2.5.4.32"
+#define RTCRX500_ID_AT_ROLE_OCCUPANT_OID                    "2.5.4.33"
+#define RTCRX500_ID_AT_SEE_ALSO_OID                         "2.5.4.34"
+#define RTCRX500_ID_AT_USER_PASSWORD_OID                    "2.5.4.35"
+#define RTCRX500_ID_AT_USER_CERTIFICATE_OID                 "2.5.4.36"
+#define RTCRX500_ID_AT_CA_CERTIFICATE_OID                   "2.5.4.37"
+#define RTCRX500_ID_AT_AUTHORITY_REVOCATION_LIST_OID        "2.5.4.38"
+#define RTCRX500_ID_AT_CERTIFICATE_REVOCATION_LIST_OID      "2.5.4.39"
+#define RTCRX500_ID_AT_CROSS_CERTIFICATE_PAIR_OID           "2.5.4.40"
+#define RTCRX500_ID_AT_NAME_OID                             "2.5.4.41"
+#define RTCRX500_ID_AT_GIVEN_NAME_OID                       "2.5.4.42"
+#define RTCRX500_ID_AT_INITIALS_OID                         "2.5.4.43"
+#define RTCRX500_ID_AT_GENERATION_QUALIFIER_OID             "2.5.4.44"
+#define RTCRX500_ID_AT_UNIQUE_IDENTIFIER_OID                "2.5.4.45"
+#define RTCRX500_ID_AT_DN_QUALIFIER_OID                     "2.5.4.46"
+#define RTCRX500_ID_AT_ENHANCHED_SEARCH_GUIDE_OID           "2.5.4.47"
+#define RTCRX500_ID_AT_PROTOCOL_INFORMATION_OID             "2.5.4.48"
+#define RTCRX500_ID_AT_DISTINGUISHED_NAME_OID               "2.5.4.49"
+#define RTCRX500_ID_AT_UNIQUE_MEMBER_OID                    "2.5.4.50"
+#define RTCRX500_ID_AT_HOUSE_IDENTIFIER_OID                 "2.5.4.51"
+#define RTCRX500_ID_AT_SUPPORTED_ALGORITHMS_OID             "2.5.4.52"
+#define RTCRX500_ID_AT_DELTA_REVOCATION_LIST_OID            "2.5.4.53"
+#define RTCRX500_ID_AT_ATTRIBUTE_CERTIFICATE_OID            "2.5.4.58"
+#define RTCRX500_ID_AT_PSEUDONYM_OID                        "2.5.4.65"
+/** @} */
+
+
+static void rtCrX509NameDump(PCRTCRX509NAME pName, PFNRTDUMPPRINTFV pfnPrintfV, void *pvUser)
+{
+    for (uint32_t i = 0; i < pName->cItems; i++)
+    {
+        PCRTCRX509RELATIVEDISTINGUISHEDNAME const pRdn = pName->papItems[i];
+        for (uint32_t j = 0; j < pRdn->cItems; j++)
+        {
+            PRTCRX509ATTRIBUTETYPEANDVALUE pAttrib = pRdn->papItems[j];
+
+            const char *pszType = pAttrib->Type.szObjId;
+            if (   !strncmp(pAttrib->Type.szObjId, "2.5.4.", 6)
+                && (pAttrib->Type.szObjId[8] == '\0' || pAttrib->Type.szObjId[9] == '\0'))
+            {
+                switch (RTStrToUInt8(&pAttrib->Type.szObjId[6]))
+                {
+                    case  3: pszType = "cn"; break;
+                    case  4: pszType = "sn"; break;
+                    case  5: pszType = "serialNumber"; break;
+                    case  6: pszType = "c"; break;
+                    case  7: pszType = "l"; break;
+                    case  8: pszType = "st"; break;
+                    case  9: pszType = "street"; break;
+                    case 10: pszType = "o"; break;
+                    case 11: pszType = "ou"; break;
+                    case 13: pszType = "description"; break;
+                    case 15: pszType = "businessCategory"; break;
+                    case 16: pszType = "postalAddress"; break;
+                    case 17: pszType = "postalCode"; break;
+                    case 18: pszType = "postOfficeBox"; break;
+                    case 20: pszType = "telephoneNumber"; break;
+                    case 26: pszType = "registeredAddress"; break;
+                    case 31: pszType = "member"; break;
+                    case 41: pszType = "name"; break;
+                    case 42: pszType = "givenName"; break;
+                    case 43: pszType = "initials"; break;
+                    case 45: pszType = "x500UniqueIdentifier"; break;
+                    case 50: pszType = "uniqueMember"; break;
+                }
+            }
+            rtDumpPrintf(pfnPrintfV, pvUser, "/%s=", pszType);
+            if (pAttrib->Value.enmType == RTASN1TYPE_STRING)
+            {
+                if (pAttrib->Value.u.String.pszUtf8)
+                    rtDumpPrintf(pfnPrintfV, pvUser, "%s", pAttrib->Value.u.String.pszUtf8);
+                else
+                {
+                    const char *pch = pAttrib->Value.u.String.Asn1Core.uData.pch;
+                    uint32_t    cch = pAttrib->Value.u.String.Asn1Core.cb;
+                    int rc = RTStrValidateEncodingEx(pch, cch, 0);
+                    if (RT_SUCCESS(rc) && cch)
+                        rtDumpPrintf(pfnPrintfV, pvUser, "%.*s", (size_t)cch, pch);
+                    else
+                        while (cch > 0)
+                        {
+                            if (RT_C_IS_PRINT(*pch))
+                                rtDumpPrintf(pfnPrintfV, pvUser, "%c", *pch);
+                            else
+                                rtDumpPrintf(pfnPrintfV, pvUser, "\\x%02x", *pch);
+                            cch--;
+                            pch++;
+                        }
+                }
+            }
+            else
+                rtDumpPrintf(pfnPrintfV, pvUser, "<not-string: uTag=%#x>", pAttrib->Value.u.Core.uTag);
+        }
+    }
+}
+
+
+static const char *rtCrX509CertPathsNodeGetSourceName(PRTCRX509CERTPATHNODE pNode)
+{
+    switch (pNode->uSrc)
+    {
+        case RTCRX509CERTPATHNODE_SRC_TARGET:           return "target";
+        case RTCRX509CERTPATHNODE_SRC_UNTRUSTED_SET:    return "untrusted_set";
+        case RTCRX509CERTPATHNODE_SRC_UNTRUSTED_ARRAY:  return "untrusted_array";
+        case RTCRX509CERTPATHNODE_SRC_UNTRUSTED_STORE:  return "untrusted_store";
+        case RTCRX509CERTPATHNODE_SRC_TRUSTED_STORE:    return "trusted_store";
+        case RTCRX509CERTPATHNODE_SRC_TRUSTED_CERT:     return "trusted_cert";
+        default:                                        return "invalid";
+    }
+}
+
+
+static void rtCrX509CertPathsDumpOneWorker(PRTCRX509CERTPATHSINT pThis, uint32_t iPath, PRTCRX509CERTPATHNODE pCurLeaf,
+                                           uint32_t uVerbosity, PFNRTDUMPPRINTFV pfnPrintfV, void *pvUser)
+{
+    RT_NOREF_PV(pThis);
+    rtDumpPrintf(pfnPrintfV, pvUser, "Path #%u: %s, %u deep, rcVerify=%Rrc\n",
+                 iPath, RTCRX509CERTPATHNODE_SRC_IS_TRUSTED(pCurLeaf->uSrc) ? "trusted" : "untrusted", pCurLeaf->uDepth,
+                 pCurLeaf->rcVerify);
+
+    for (uint32_t iIndent = 2; pCurLeaf; iIndent += 2, pCurLeaf = pCurLeaf->pParent)
+    {
+        if (pCurLeaf->pCert)
+        {
+            rtDumpIndent(pfnPrintfV, pvUser, iIndent, "Issuer : ");
+            rtCrX509NameDump(&pCurLeaf->pCert->TbsCertificate.Issuer, pfnPrintfV, pvUser);
+            rtDumpPrintf(pfnPrintfV, pvUser, "\n");
+
+            rtDumpIndent(pfnPrintfV, pvUser, iIndent, "Subject: ");
+            rtCrX509NameDump(&pCurLeaf->pCert->TbsCertificate.Subject, pfnPrintfV, pvUser);
+            rtDumpPrintf(pfnPrintfV, pvUser, "\n");
+
+            if (uVerbosity >= 4)
+                RTAsn1Dump(&pCurLeaf->pCert->SeqCore.Asn1Core, 0, iIndent, pfnPrintfV, pvUser);
+            else if (uVerbosity >= 3)
+                RTAsn1Dump(&pCurLeaf->pCert->TbsCertificate.T3.Extensions.SeqCore.Asn1Core, 0, iIndent, pfnPrintfV, pvUser);
+        }
+        else
+        {
+            Assert(pCurLeaf->pCertCtx); Assert(pCurLeaf->pCertCtx->pTaInfo);
+            rtDumpIndent(pfnPrintfV, pvUser, iIndent, "Subject: ");
+            rtCrX509NameDump(&pCurLeaf->pCertCtx->pTaInfo->CertPath.TaName, pfnPrintfV, pvUser);
+
+            if (uVerbosity >= 4)
+                RTAsn1Dump(&pCurLeaf->pCertCtx->pTaInfo->SeqCore.Asn1Core, 0, iIndent, pfnPrintfV, pvUser);
+        }
+
+        const char *pszSrc = rtCrX509CertPathsNodeGetSourceName(pCurLeaf);
+        rtDumpIndent(pfnPrintfV, pvUser, iIndent, "Source : %s\n", pszSrc);
+    }
+}
+
+
+RTDECL(int) RTCrX509CertPathsDumpOne(RTCRX509CERTPATHS hCertPaths, uint32_t iPath, uint32_t uVerbosity,
+                                     PFNRTDUMPPRINTFV pfnPrintfV, void *pvUser)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertPtrReturn(pfnPrintfV, VERR_INVALID_POINTER);
+    int rc;
+    if (iPath < pThis->cPaths)
+    {
+        PRTCRX509CERTPATHNODE pLeaf = rtCrX509CertPathsGetLeafByIndex(pThis, iPath);
+        if (pLeaf)
+        {
+            rtCrX509CertPathsDumpOneWorker(pThis, iPath, pLeaf, uVerbosity, pfnPrintfV, pvUser);
+            rc = VINF_SUCCESS;
+        }
+        else
+            rc = VERR_CR_X509_CERTPATHS_INTERNAL_ERROR;
+    }
+    else
+        rc = VERR_NOT_FOUND;
+    return rc;
+}
+
+
+RTDECL(int) RTCrX509CertPathsDumpAll(RTCRX509CERTPATHS hCertPaths, uint32_t uVerbosity, PFNRTDUMPPRINTFV pfnPrintfV, void *pvUser)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertPtrReturn(pfnPrintfV, VERR_INVALID_POINTER);
+
+    /*
+     * Dump all the paths.
+     */
+    rtDumpPrintf(pfnPrintfV, pvUser, "%u paths, rc=%Rrc\n", pThis->cPaths, pThis->rc);
+    uint32_t iPath = 0;
+    PRTCRX509CERTPATHNODE pCurLeaf, pNextLeaf;
+    RTListForEachSafe(&pThis->LeafList, pCurLeaf, pNextLeaf, RTCRX509CERTPATHNODE, ChildListOrLeafEntry)
+    {
+        rtCrX509CertPathsDumpOneWorker(pThis, iPath, pCurLeaf, uVerbosity, pfnPrintfV, pvUser);
+        iPath++;
+    }
+
+    return VINF_SUCCESS;
+}
+
+
+/** @} */
+
+
+/** @name Path Validator Functions.
+ * @{
+ */
+
+
+static void *rtCrX509CpvAllocZ(PRTCRX509CERTPATHSINT pThis, size_t cb, const char *pszWhat)
+{
+    void *pv = RTMemAllocZ(cb);
+    if (!pv)
+        pThis->rc = RTErrInfoSetF(pThis->pErrInfo, VERR_NO_MEMORY, "Failed to allocate %zu bytes for %s", cb, pszWhat);
+    return pv;
+}
+
+
+DECL_NO_INLINE(static, bool) rtCrX509CpvFailed(PRTCRX509CERTPATHSINT pThis, int rc, const char *pszFormat, ...)
+{
+    va_list va;
+    va_start(va, pszFormat);
+    pThis->rc = RTErrInfoSetV(pThis->pErrInfo, rc, pszFormat, va);
+    va_end(va);
+    return false;
+}
+
+
+/**
+ * Adds a sequence of excluded sub-trees.
+ *
+ * Don't waste time optimizing the output if this is supposed to be a union.
+ * Unless the path is very long, it's a lot more work to optimize and the result
+ * will be the same anyway.
+ *
+ * @returns success indicator.
+ * @param   pThis               The validator instance.
+ * @param   pSubtrees           The sequence of sub-trees to add.
+ */
+static bool rtCrX509CpvAddExcludedSubtrees(PRTCRX509CERTPATHSINT pThis, PCRTCRX509GENERALSUBTREES pSubtrees)
+{
+    if (((pThis->v.cExcludedSubtrees + 1) & 0xf) == 0)
+    {
+        void *pvNew = RTMemRealloc(pThis->v.papExcludedSubtrees,
+                                   (pThis->v.cExcludedSubtrees + 16) * sizeof(pThis->v.papExcludedSubtrees[0]));
+        if (RT_UNLIKELY(!pvNew))
+            return rtCrX509CpvFailed(pThis, VERR_NO_MEMORY, "Error growing subtrees pointer array to %u elements",
+                                     pThis->v.cExcludedSubtrees + 16);
+        pThis->v.papExcludedSubtrees = (PCRTCRX509GENERALSUBTREES *)pvNew;
+    }
+    pThis->v.papExcludedSubtrees[pThis->v.cExcludedSubtrees] = pSubtrees;
+    pThis->v.cExcludedSubtrees++;
+    return true;
+}
+
+
+/**
+ * Checks if a sub-tree is according to RFC-5280.
+ *
+ * @returns Success indiciator.
+ * @param   pThis               The validator instance.
+ * @param   pSubtree            The subtree to check.
+ */
+static bool rtCrX509CpvCheckSubtreeValidity(PRTCRX509CERTPATHSINT pThis, PCRTCRX509GENERALSUBTREE pSubtree)
+{
+    if (   pSubtree->Base.enmChoice <= RTCRX509GENERALNAMECHOICE_INVALID
+        || pSubtree->Base.enmChoice >= RTCRX509GENERALNAMECHOICE_END)
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_UNEXP_GENERAL_SUBTREE_CHOICE,
+                                 "Unexpected GeneralSubtree choice %#x", pSubtree->Base.enmChoice);
+
+    if (RTAsn1Integer_UnsignedCompareWithU32(&pSubtree->Minimum, 0) != 0)
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_UNEXP_GENERAL_SUBTREE_MIN,
+                                 "Unexpected GeneralSubtree Minimum value: %#llx",
+                                 pSubtree->Minimum.uValue);
+
+    if (RTAsn1Integer_IsPresent(&pSubtree->Maximum))
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_UNEXP_GENERAL_SUBTREE_MAX,
+                                 "Unexpected GeneralSubtree Maximum value: %#llx",
+                                 pSubtree->Maximum.uValue);
+
+    return true;
+}
+
+
+/**
+ * Grows the array of permitted sub-trees.
+ *
+ * @returns success indiciator.
+ * @param   pThis               The validator instance.
+ * @param   cAdding             The number of subtrees we should grow by
+ *                              (relative to the current number of valid
+ *                              entries).
+ */
+static bool rtCrX509CpvGrowPermittedSubtrees(PRTCRX509CERTPATHSINT pThis, uint32_t cAdding)
+{
+    uint32_t cNew = RT_ALIGN_32(pThis->v.cPermittedSubtrees + cAdding, 16);
+    if (cNew > pThis->v.cPermittedSubtreesAlloc)
+    {
+        if (cNew >= _4K)
+            return rtCrX509CpvFailed(pThis, VERR_NO_MEMORY, "Too many permitted subtrees: %u (cur %u)",
+                                     cNew, pThis->v.cPermittedSubtrees);
+        void *pvNew = RTMemRealloc(pThis->v.papPermittedSubtrees, cNew * sizeof(pThis->v.papPermittedSubtrees[0]));
+        if (RT_UNLIKELY(!pvNew))
+            return rtCrX509CpvFailed(pThis, VERR_NO_MEMORY, "Error growing subtrees pointer array from %u to %u elements",
+                                     pThis->v.cPermittedSubtreesAlloc, cNew);
+        pThis->v.papPermittedSubtrees = (PCRTCRX509GENERALSUBTREE *)pvNew;
+    }
+    return true;
+}
+
+
+/**
+ * Adds a sequence of permitted sub-trees.
+ *
+ * We store reference to each individual sub-tree because we must support
+ * intersection calculation.
+ *
+ * @returns success indiciator.
+ * @param   pThis               The validator instance.
+ * @param   cSubtrees           The number of sub-trees to add.
+ * @param   papSubtrees         Array of sub-trees to add.
+ */
+static bool rtCrX509CpvAddPermittedSubtrees(PRTCRX509CERTPATHSINT pThis, uint32_t cSubtrees,
+                                            PRTCRX509GENERALSUBTREE const *papSubtrees)
+{
+    /*
+     * If the array is empty, assume no permitted names.
+     */
+    if (!cSubtrees)
+    {
+        pThis->v.fNoPermittedSubtrees = true;
+        return true;
+    }
+
+    /*
+     * Grow the array if necessary.
+     */
+    if (!rtCrX509CpvGrowPermittedSubtrees(pThis, cSubtrees))
+        return false;
+
+    /*
+     * Append each subtree to the array.
+     */
+    uint32_t iDst = pThis->v.cPermittedSubtrees;
+    for (uint32_t iSrc = 0; iSrc < cSubtrees; iSrc++)
+    {
+        if (!rtCrX509CpvCheckSubtreeValidity(pThis, papSubtrees[iSrc]))
+            return false;
+        pThis->v.papPermittedSubtrees[iDst] = papSubtrees[iSrc];
+        iDst++;
+    }
+    pThis->v.cPermittedSubtrees = iDst;
+
+    return true;
+}
+
+
+/**
+ * Adds a one permitted sub-tree.
+ *
+ * We store reference to each individual sub-tree because we must support
+ * intersection calculation.
+ *
+ * @returns success indiciator.
+ * @param   pThis               The validator instance.
+ * @param   pSubtree            Array of sub-trees to add.
+ */
+static bool rtCrX509CpvAddPermittedSubtree(PRTCRX509CERTPATHSINT pThis, PCRTCRX509GENERALSUBTREE pSubtree)
+{
+    return rtCrX509CpvAddPermittedSubtrees(pThis, 1, (PRTCRX509GENERALSUBTREE const *)&pSubtree);
+}
+
+
+/**
+ * Calculates the intersection between @a pSubtrees and the current permitted
+ * sub-trees.
+ *
+ * @returns Success indicator.
+ * @param   pThis               The validator instance.
+ * @param   pSubtrees           The sub-tree sequence to intersect with.
+ */
+static bool rtCrX509CpvIntersectionPermittedSubtrees(PRTCRX509CERTPATHSINT pThis, PCRTCRX509GENERALSUBTREES pSubtrees)
+{
+    /*
+     * Deal with special cases first.
+     */
+    if (pThis->v.fNoPermittedSubtrees)
+    {
+        Assert(pThis->v.cPermittedSubtrees == 0);
+        return true;
+    }
+
+    uint32_t                       cRight   = pSubtrees->cItems;
+    PRTCRX509GENERALSUBTREE const *papRight = pSubtrees->papItems;
+    if (cRight == 0)
+    {
+        pThis->v.cPermittedSubtrees = 0;
+        pThis->v.fNoPermittedSubtrees = true;
+        return true;
+    }
+
+    uint32_t                    cLeft   = pThis->v.cPermittedSubtrees;
+    PCRTCRX509GENERALSUBTREE   *papLeft = pThis->v.papPermittedSubtrees;
+    if (!cLeft) /* first name constraint, no initial constraint */
+        return rtCrX509CpvAddPermittedSubtrees(pThis, cRight, papRight);
+
+    /*
+     * Create a new array with the intersection, freeing the old (left) array
+     * once we're done.
+     */
+    bool afRightTags[RTCRX509GENERALNAMECHOICE_END] = { 0, 0, 0, 0,  0, 0, 0, 0,  0 };
+
+    pThis->v.cPermittedSubtrees      = 0;
+    pThis->v.cPermittedSubtreesAlloc = 0;
+    pThis->v.papPermittedSubtrees    = NULL;
+
+    for (uint32_t iRight = 0; iRight < cRight; iRight++)
+    {
+        if (!rtCrX509CpvCheckSubtreeValidity(pThis, papRight[iRight]))
+            return false;
+
+        RTCRX509GENERALNAMECHOICE const enmRightChoice = papRight[iRight]->Base.enmChoice;
+        afRightTags[enmRightChoice] = true;
+
+        bool fHaveRight = false;
+        for (uint32_t iLeft = 0; iLeft < cLeft; iLeft++)
+            if (papLeft[iLeft]->Base.enmChoice == enmRightChoice)
+            {
+                if (RTCrX509GeneralSubtree_Compare(papLeft[iLeft], papRight[iRight]) == 0)
+                {
+                    if (!fHaveRight)
+                    {
+                        fHaveRight = true;
+                        rtCrX509CpvAddPermittedSubtree(pThis, papLeft[iLeft]);
+                    }
+                }
+                else if (RTCrX509GeneralSubtree_ConstraintMatch(papLeft[iLeft], papRight[iRight]))
+                {
+                    if (!fHaveRight)
+                    {
+                        fHaveRight = true;
+                        rtCrX509CpvAddPermittedSubtree(pThis, papRight[iRight]);
+                    }
+                }
+                else if (RTCrX509GeneralSubtree_ConstraintMatch(papRight[iRight], papLeft[iLeft]))
+                    rtCrX509CpvAddPermittedSubtree(pThis, papLeft[iLeft]);
+            }
+    }
+
+    /*
+     * Add missing types not specified in the right set.
+     */
+    for (uint32_t iLeft = 0; iLeft < cLeft; iLeft++)
+        if (!afRightTags[papLeft[iLeft]->Base.enmChoice])
+            rtCrX509CpvAddPermittedSubtree(pThis, papLeft[iLeft]);
+
+    /*
+     * If we ended up with an empty set, no names are permitted any more.
+     */
+    if (pThis->v.cPermittedSubtrees == 0)
+        pThis->v.fNoPermittedSubtrees = true;
+
+    RTMemFree(papLeft);
+    return RT_SUCCESS(pThis->rc);
+}
+
+
+/**
+ * Check if the given X.509 name is permitted by current name constraints.
+ *
+ * @returns true is permitteded, false if not (caller set error info).
+ * @param   pThis       The validator instance.
+ * @param   pName       The name to match.
+ */
+static bool rtCrX509CpvIsNamePermitted(PRTCRX509CERTPATHSINT pThis, PCRTCRX509NAME pName)
+{
+    uint32_t i = pThis->v.cPermittedSubtrees;
+    if (i == 0)
+        return !pThis->v.fNoPermittedSubtrees;
+
+    while (i-- > 0)
+    {
+        PCRTCRX509GENERALSUBTREE pConstraint = pThis->v.papPermittedSubtrees[i];
+        if (   RTCRX509GENERALNAME_IS_DIRECTORY_NAME(&pConstraint->Base)
+            && RTCrX509Name_ConstraintMatch(&pConstraint->Base.u.pT4->DirectoryName, pName))
+            return true;
+    }
+    return false;
+}
+
+
+/**
+ * Check if the given X.509 general name is permitted by current name
+ * constraints.
+ *
+ * @returns true is permitteded, false if not (caller sets error info).
+ * @param   pThis           The validator instance.
+ * @param   pGeneralName    The name to match.
+ */
+static bool rtCrX509CpvIsGeneralNamePermitted(PRTCRX509CERTPATHSINT pThis, PCRTCRX509GENERALNAME pGeneralName)
+{
+    uint32_t i = pThis->v.cPermittedSubtrees;
+    if (i == 0)
+        return !pThis->v.fNoPermittedSubtrees;
+
+    while (i-- > 0)
+        if (RTCrX509GeneralName_ConstraintMatch(&pThis->v.papPermittedSubtrees[i]->Base, pGeneralName))
+            return true;
+    return false;
+}
+
+
+/**
+ * Check if the given X.509 name is excluded by current name constraints.
+ *
+ * @returns true if excluded (caller sets error info), false if not explicitly
+ *          excluded.
+ * @param   pThis       The validator instance.
+ * @param   pName       The name to match.
+ */
+static bool rtCrX509CpvIsNameExcluded(PRTCRX509CERTPATHSINT pThis, PCRTCRX509NAME pName)
+{
+    uint32_t i = pThis->v.cExcludedSubtrees;
+    while (i-- > 0)
+    {
+        PCRTCRX509GENERALSUBTREES pSubTrees = pThis->v.papExcludedSubtrees[i];
+        uint32_t j = pSubTrees->cItems;
+        while (j-- > 0)
+        {
+            PCRTCRX509GENERALSUBTREE const pSubTree = pSubTrees->papItems[j];
+            if (   RTCRX509GENERALNAME_IS_DIRECTORY_NAME(&pSubTree->Base)
+                && RTCrX509Name_ConstraintMatch(&pSubTree->Base.u.pT4->DirectoryName, pName))
+                return true;
+        }
+    }
+    return false;
+}
+
+
+/**
+ * Check if the given X.509 general name is excluded by current name
+ * constraints.
+ *
+ * @returns true if excluded (caller sets error info), false if not explicitly
+ *          excluded.
+ * @param   pThis           The validator instance.
+ * @param   pGeneralName    The name to match.
+ */
+static bool rtCrX509CpvIsGeneralNameExcluded(PRTCRX509CERTPATHSINT pThis, PCRTCRX509GENERALNAME pGeneralName)
+{
+    uint32_t i = pThis->v.cExcludedSubtrees;
+    while (i-- > 0)
+    {
+        PCRTCRX509GENERALSUBTREES pSubTrees = pThis->v.papExcludedSubtrees[i];
+        uint32_t j = pSubTrees->cItems;
+        while (j-- > 0)
+            if (RTCrX509GeneralName_ConstraintMatch(&pSubTrees->papItems[j]->Base, pGeneralName))
+                return true;
+    }
+    return false;
+}
+
+
+/**
+ * Creates a new node and inserts it.
+ *
+ * @param   pThis           The path builder & validator instance.
+ * @param   pParent         The parent node. NULL for the root node.
+ * @param   iDepth          The tree depth to insert at.
+ * @param   pValidPolicy    The valid policy of the new node.
+ * @param   pQualifiers     The qualifiers of the new node.
+ * @param   pExpectedPolicy The (first) expected polcy of the new node.
+ */
+static bool rtCrX509CpvPolicyTreeInsertNew(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHSPOLICYNODE pParent, uint32_t iDepth,
+                                           PCRTASN1OBJID pValidPolicy, PCRTCRX509POLICYQUALIFIERINFOS pQualifiers,
+                                           PCRTASN1OBJID pExpectedPolicy)
+{
+    Assert(iDepth <= pThis->v.cNodes);
+
+    PRTCRX509CERTPATHSPOLICYNODE pNode;
+    pNode = (PRTCRX509CERTPATHSPOLICYNODE)rtCrX509CpvAllocZ(pThis, sizeof(*pNode), "policy tree node");
+    if (pNode)
+    {
+        pNode->pParent = pParent;
+        if (pParent)
+            RTListAppend(&pParent->ChildList, &pNode->SiblingEntry);
+        else
+        {
+            Assert(pThis->v.pValidPolicyTree == NULL);
+            pThis->v.pValidPolicyTree = pNode;
+            RTListInit(&pNode->SiblingEntry);
+        }
+        RTListInit(&pNode->ChildList);
+        RTListAppend(&pThis->v.paValidPolicyDepthLists[iDepth], &pNode->DepthEntry);
+
+        pNode->pValidPolicy = pValidPolicy;
+        pNode->pPolicyQualifiers = pQualifiers;
+        pNode->pExpectedPolicyFirst = pExpectedPolicy;
+        pNode->cMoreExpectedPolicySet = 0;
+        pNode->papMoreExpectedPolicySet = NULL;
+        return true;
+    }
+    return false;
+}
+
+
+/**
+ * Unlinks and frees a node in the valid policy tree.
+ *
+ * @param   pThis           The path builder & validator instance.
+ * @param   pNode           The node to destroy.
+ */
+static void rtCrX509CpvPolicyTreeDestroyNode(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHSPOLICYNODE pNode)
+{
+    Assert(RTListIsEmpty(&pNode->ChildList));
+    if (pNode->pParent)
+        RTListNodeRemove(&pNode->SiblingEntry);
+    else
+        pThis->v.pValidPolicyTree = NULL;
+    RTListNodeRemove(&pNode->DepthEntry);
+    pNode->pParent = NULL;
+
+    if (pNode->papMoreExpectedPolicySet)
+    {
+        RTMemFree(pNode->papMoreExpectedPolicySet);
+        pNode->papMoreExpectedPolicySet = NULL;
+    }
+    RTMemFree(pNode);
+}
+
+
+/**
+ * Unlinks and frees a sub-tree in the valid policy tree.
+ *
+ * @param   pThis           The path builder & validator instance.
+ * @param   pNode           The node that is the root of the subtree.
+ */
+static void rtCrX509CpvPolicyTreeDestroySubtree(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHSPOLICYNODE pNode)
+{
+    if (!RTListIsEmpty(&pNode->ChildList))
+    {
+        PRTCRX509CERTPATHSPOLICYNODE pCur = pNode;
+        do
+        {
+            Assert(!RTListIsEmpty(&pCur->ChildList));
+
+            /* Decend until we find a leaf. */
+            do
+                pCur = RTListGetFirst(&pCur->ChildList, RTCRX509CERTPATHSPOLICYNODE, SiblingEntry);
+            while (!RTListIsEmpty(&pCur->ChildList));
+
+            /* Remove it and all leafy siblings. */
+            PRTCRX509CERTPATHSPOLICYNODE pParent = pCur->pParent;
+            do
+            {
+                Assert(pCur != pNode);
+                rtCrX509CpvPolicyTreeDestroyNode(pThis, pCur);
+                pCur = RTListGetFirst(&pParent->ChildList, RTCRX509CERTPATHSPOLICYNODE, SiblingEntry);
+                if (!pCur)
+                {
+                    pCur = pParent;
+                    pParent = pParent->pParent;
+                }
+            } while (RTListIsEmpty(&pCur->ChildList) && pCur != pNode);
+        } while (pCur != pNode);
+    }
+
+    rtCrX509CpvPolicyTreeDestroyNode(pThis, pNode);
+}
+
+
+
+/**
+ * Destroys the entire policy tree.
+ *
+ * @param   pThis           The path builder & validator instance.
+ */
+static void rtCrX509CpvPolicyTreeDestroy(PRTCRX509CERTPATHSINT pThis)
+{
+    uint32_t i = pThis->v.cNodes + 1;
+    while (i-- > 0)
+    {
+        PRTCRX509CERTPATHSPOLICYNODE pCur, pNext;
+        RTListForEachSafe(&pThis->v.paValidPolicyDepthLists[i], pCur, pNext, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+        {
+            rtCrX509CpvPolicyTreeDestroyNode(pThis, pCur);
+        }
+    }
+}
+
+
+/**
+ * Removes all leaf nodes at level @a iDepth and above.
+ *
+ * @param   pThis           The path builder & validator instance.
+ * @param   iDepth          The depth to start pruning at.
+ */
+static void rtCrX509CpvPolicyTreePrune(PRTCRX509CERTPATHSINT pThis, uint32_t iDepth)
+{
+    do
+    {
+        PRTLISTANCHOR pList = &pThis->v.paValidPolicyDepthLists[iDepth];
+        PRTCRX509CERTPATHSPOLICYNODE pCur, pNext;
+        RTListForEachSafe(pList, pCur, pNext, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+        {
+            if (RTListIsEmpty(&pCur->ChildList))
+                rtCrX509CpvPolicyTreeDestroyNode(pThis, pCur);
+        }
+
+    } while (iDepth-- > 0);
+}
+
+
+/**
+ * Checks if @a pPolicy is the valid policy of a child of @a pNode.
+ *
+ * @returns true if in child node, false if not.
+ * @param   pNode           The node which children to check.
+ * @param   pPolicy         The valid policy to look for among the children.
+ */
+static bool rtCrX509CpvPolicyTreeIsChild(PRTCRX509CERTPATHSPOLICYNODE pNode, PCRTASN1OBJID pPolicy)
+{
+    PRTCRX509CERTPATHSPOLICYNODE pChild;
+    RTListForEach(&pNode->ChildList, pChild, RTCRX509CERTPATHSPOLICYNODE, SiblingEntry)
+    {
+        if (RTAsn1ObjId_Compare(pChild->pValidPolicy, pPolicy) == 0)
+            return true;
+    }
+    return true;
+}
+
+
+/**
+ * Prunes the valid policy tree according to the specified user policy set.
+ *
+ * @returns Pointer to the policy object from @a papPolicies if found, NULL if
+ *          no match.
+ * @param   pObjId          The object ID to locate at match in the set.
+ * @param   cPolicies       The number of policies in @a papPolicies.
+ * @param   papPolicies     The policy set to search.
+ */
+static PCRTASN1OBJID rtCrX509CpvFindObjIdInPolicySet(PCRTASN1OBJID pObjId, uint32_t cPolicies, PCRTASN1OBJID *papPolicies)
+{
+    uint32_t i = cPolicies;
+    while (i-- > 0)
+        if (RTAsn1ObjId_Compare(pObjId, papPolicies[i]) == 0)
+            return papPolicies[i];
+    return NULL;
+}
+
+
+/**
+ * Prunes the valid policy tree according to the specified user policy set.
+ *
+ * @returns success indicator (allocates memory)
+ * @param   pThis           The path builder & validator instance.
+ * @param   cPolicies       The number of policies in @a papPolicies.
+ * @param   papPolicies     The user initial policies.
+ */
+static bool rtCrX509CpvPolicyTreeIntersect(PRTCRX509CERTPATHSINT pThis, uint32_t cPolicies, PCRTASN1OBJID *papPolicies)
+{
+    /*
+     * 4.1.6.g.i - NULL tree remains NULL.
+     */
+    if (!pThis->v.pValidPolicyTree)
+        return true;
+
+    /*
+     * 4.1.6.g.ii - If the user set includes anyPolicy, the whole tree is the
+     *              result of the intersection.
+     */
+    uint32_t i = cPolicies;
+    while (i-- > 0)
+        if (RTAsn1ObjId_CompareWithString(papPolicies[i], RTCRX509_ID_CE_CP_ANY_POLICY_OID) == 0)
+            return true;
+
+    /*
+     * 4.1.6.g.iii - Complicated.
+     */
+    PRTCRX509CERTPATHSPOLICYNODE pCur, pNext;
+    PRTLISTANCHOR pList;
+
+    /* 1 & 2: Delete nodes which parent has valid policy == anyPolicy and which
+              valid policy is neither anyPolicy nor a member of papszPolicies.
+              While doing so, construct a set of unused user policies that
+              we'll replace anyPolicy nodes with in step 3. */
+    uint32_t        cPoliciesLeft   = 0;
+    PCRTASN1OBJID  *papPoliciesLeft = NULL;
+    if (cPolicies)
+    {
+        papPoliciesLeft = (PCRTASN1OBJID *)rtCrX509CpvAllocZ(pThis, cPolicies * sizeof(papPoliciesLeft[0]), "papPoliciesLeft");
+        if (!papPoliciesLeft)
+            return false;
+        for (i = 0; i < cPolicies; i++)
+            papPoliciesLeft[i] = papPolicies[i];
+    }
+
+    for (uint32_t iDepth = 1; iDepth <= pThis->v.cNodes; iDepth++)
+    {
+        pList = &pThis->v.paValidPolicyDepthLists[iDepth];
+        RTListForEachSafe(pList, pCur, pNext, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+        {
+            Assert(pCur->pParent);
+            if (   RTAsn1ObjId_CompareWithString(pCur->pParent->pValidPolicy, RTCRX509_ID_CE_CP_ANY_POLICY_OID) == 0
+                && RTAsn1ObjId_CompareWithString(pCur->pValidPolicy, RTCRX509_ID_CE_CP_ANY_POLICY_OID) != 0)
+            {
+                PCRTASN1OBJID pFound = rtCrX509CpvFindObjIdInPolicySet(pCur->pValidPolicy, cPolicies, papPolicies);
+                if (!pFound)
+                    rtCrX509CpvPolicyTreeDestroySubtree(pThis, pCur);
+                else
+                    for (i = 0; i < cPoliciesLeft; i++)
+                        if (papPoliciesLeft[i] == pFound)
+                        {
+                            cPoliciesLeft--;
+                            if (i < cPoliciesLeft)
+                                papPoliciesLeft[i] = papPoliciesLeft[cPoliciesLeft];
+                            papPoliciesLeft[cPoliciesLeft] = NULL;
+                            break;
+                        }
+            }
+        }
+    }
+
+    /*
+     * 4.1.5.g.iii.3 - Replace anyPolicy nodes on the final tree depth with
+     *                 the policies in papPoliciesLeft.
+     */
+    pList = &pThis->v.paValidPolicyDepthLists[pThis->v.cNodes];
+    RTListForEachSafe(pList, pCur, pNext, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+    {
+        if (RTAsn1ObjId_CompareWithString(pCur->pValidPolicy, RTCRX509_ID_CE_CP_ANY_POLICY_OID) == 0)
+        {
+            for (i = 0; i < cPoliciesLeft; i++)
+                rtCrX509CpvPolicyTreeInsertNew(pThis, pCur->pParent, pThis->v.cNodes - 1,
+                                               papPoliciesLeft[i], pCur->pPolicyQualifiers, papPoliciesLeft[i]);
+            rtCrX509CpvPolicyTreeDestroyNode(pThis, pCur);
+        }
+    }
+
+    RTMemFree(papPoliciesLeft);
+
+    /*
+     * 4.1.5.g.iii.4 - Prune the tree
+     */
+    rtCrX509CpvPolicyTreePrune(pThis, pThis->v.cNodes - 1);
+
+    return RT_SUCCESS(pThis->rc);
+}
+
+
+
+/**
+ * Frees the path validator state.
+ *
+ * @param   pThis           The path builder & validator instance.
+ */
+static void rtCrX509CpvCleanup(PRTCRX509CERTPATHSINT pThis)
+{
+    /*
+     * Destroy the policy tree and all its nodes.  We do this from the bottom
+     * up via the depth lists, saving annoying tree traversal.
+     */
+    if (pThis->v.paValidPolicyDepthLists)
+    {
+        rtCrX509CpvPolicyTreeDestroy(pThis);
+
+        RTMemFree(pThis->v.paValidPolicyDepthLists);
+        pThis->v.paValidPolicyDepthLists = NULL;
+    }
+
+    Assert(pThis->v.pValidPolicyTree == NULL);
+    pThis->v.pValidPolicyTree = NULL;
+
+    /*
+     * Destroy the name constraint arrays.
+     */
+    if (pThis->v.papPermittedSubtrees)
+    {
+        RTMemFree(pThis->v.papPermittedSubtrees);
+        pThis->v.papPermittedSubtrees = NULL;
+    }
+    pThis->v.cPermittedSubtrees = 0;
+    pThis->v.cPermittedSubtreesAlloc = 0;
+    pThis->v.fNoPermittedSubtrees = false;
+
+    if (pThis->v.papExcludedSubtrees)
+    {
+        RTMemFree(pThis->v.papExcludedSubtrees);
+        pThis->v.papExcludedSubtrees = NULL;
+    }
+    pThis->v.cExcludedSubtrees = 0;
+
+    /*
+     * Clear other pointers.
+     */
+    pThis->v.pWorkingIssuer              = NULL;
+    pThis->v.pWorkingPublicKey           = NULL;
+    pThis->v.pWorkingPublicKeyAlgorithm  = NULL;
+    pThis->v.pWorkingPublicKeyParameters = NULL;
+}
+
+
+
+/**
+ * Initializes the state.
+ *
+ * Caller must check pThis->rc.
+ *
+ * @param   pThis           The path builder & validator instance.
+ * @param   pTrustAnchor    The trust anchor node for the path that we're about
+ *                          to validate.
+ */
+static void rtCrX509CpvInit(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pTrustAnchor)
+{
+    rtCrX509CpvCleanup(pThis);
+
+    /*
+     * The node count does not include the trust anchor.
+     */
+    pThis->v.cNodes = pTrustAnchor->uDepth;
+
+    /*
+     * Valid policy tree starts with an anyPolicy node.
+     */
+    uint32_t i = pThis->v.cNodes + 1;
+    pThis->v.paValidPolicyDepthLists = (PRTLISTANCHOR)rtCrX509CpvAllocZ(pThis, i * sizeof(RTLISTANCHOR),
+                                                                        "paValidPolicyDepthLists");
+    if (RT_UNLIKELY(!pThis->v.paValidPolicyDepthLists))
+        return;
+    while (i-- > 0)
+        RTListInit(&pThis->v.paValidPolicyDepthLists[i]);
+
+    if (!rtCrX509CpvPolicyTreeInsertNew(pThis, NULL, 0 /* iDepth*/, &pThis->AnyPolicyObjId, NULL, &pThis->AnyPolicyObjId))
+        return;
+    Assert(!RTListIsEmpty(&pThis->v.paValidPolicyDepthLists[0])); Assert(pThis->v.pValidPolicyTree);
+
+    /*
+     * Name constrains.
+     */
+    if (pThis->pInitialPermittedSubtrees)
+        rtCrX509CpvAddPermittedSubtrees(pThis, pThis->pInitialPermittedSubtrees->cItems,
+                                        pThis->pInitialPermittedSubtrees->papItems);
+    if (pThis->pInitialExcludedSubtrees)
+        rtCrX509CpvAddExcludedSubtrees(pThis, pThis->pInitialExcludedSubtrees);
+
+    /*
+     * Counters.
+     */
+    pThis->v.cExplicitPolicy        = pThis->cInitialExplicitPolicy;
+    pThis->v.cInhibitPolicyMapping  = pThis->cInitialPolicyMappingInhibit;
+    pThis->v.cInhibitAnyPolicy      = pThis->cInitialInhibitAnyPolicy;
+    pThis->v.cMaxPathLength         = pThis->v.cNodes;
+
+    /*
+     * Certificate info from the trust anchor.
+     */
+    if (pTrustAnchor->pCert)
+    {
+        PCRTCRX509TBSCERTIFICATE const pTbsCert = &pTrustAnchor->pCert->TbsCertificate;
+        pThis->v.pWorkingIssuer                 = &pTbsCert->Subject;
+        pThis->v.pWorkingPublicKey              = &pTbsCert->SubjectPublicKeyInfo.SubjectPublicKey;
+        pThis->v.pWorkingPublicKeyAlgorithm     = &pTbsCert->SubjectPublicKeyInfo.Algorithm.Algorithm;
+        pThis->v.pWorkingPublicKeyParameters    = &pTbsCert->SubjectPublicKeyInfo.Algorithm.Parameters;
+    }
+    else
+    {
+        Assert(pTrustAnchor->pCertCtx); Assert(pTrustAnchor->pCertCtx->pTaInfo);
+
+        PCRTCRTAFTRUSTANCHORINFO const  pTaInfo = pTrustAnchor->pCertCtx->pTaInfo;
+        pThis->v.pWorkingIssuer                 = &pTaInfo->CertPath.TaName;
+        pThis->v.pWorkingPublicKey              = &pTaInfo->PubKey.SubjectPublicKey;
+        pThis->v.pWorkingPublicKeyAlgorithm     = &pTaInfo->PubKey.Algorithm.Algorithm;
+        pThis->v.pWorkingPublicKeyParameters    = &pTaInfo->PubKey.Algorithm.Parameters;
+    }
+    if (   !RTASN1CORE_IS_PRESENT(&pThis->v.pWorkingPublicKeyParameters->u.Core)
+        || pThis->v.pWorkingPublicKeyParameters->enmType == RTASN1TYPE_NULL)
+        pThis->v.pWorkingPublicKeyParameters = NULL;
+}
+
+
+/**
+ * Step 6.1.3.a.
+ */
+static bool rtCrX509CpvCheckBasicCertInfo(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    /*
+     * 6.1.3.a.1 - Verify the certificate signature.
+     */
+    int rc = RTCrX509Certificate_VerifySignature(pNode->pCert, pThis->v.pWorkingPublicKeyAlgorithm,
+                                                 pThis->v.pWorkingPublicKeyParameters, pThis->v.pWorkingPublicKey,
+                                                 pThis->pErrInfo);
+    if (RT_FAILURE(rc))
+    {
+        pThis->rc = rc;
+        return false;
+    }
+
+    /*
+     * 6.1.3.a.2 - Verify that the certificate is valid at the specified time.
+     */
+    AssertCompile(sizeof(pThis->szTmp) >= 36 * 3);
+    if (   (pThis->fFlags & RTCRX509CERTPATHSINT_F_VALID_TIME)
+        && !RTCrX509Validity_IsValidAtTimeSpec(&pNode->pCert->TbsCertificate.Validity, &pThis->ValidTime))
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_NOT_VALID_AT_TIME,
+                                 "Certificate is not valid (ValidTime=%s Validity=[%s...%s])",
+                                 RTTimeSpecToString(&pThis->ValidTime, &pThis->szTmp[0], 36),
+                                 RTTimeToString(&pNode->pCert->TbsCertificate.Validity.NotBefore.Time, &pThis->szTmp[36], 36),
+                                 RTTimeToString(&pNode->pCert->TbsCertificate.Validity.NotAfter.Time,  &pThis->szTmp[2*36], 36) );
+
+    /*
+     * 6.1.3.a.3 - Verified that the certficiate is not revoked.
+     */
+    /** @todo rainy day. */
+
+    /*
+     * 6.1.3.a.4 - Check the issuer name.
+     */
+    if (!RTCrX509Name_MatchByRfc5280(&pNode->pCert->TbsCertificate.Issuer, pThis->v.pWorkingIssuer))
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_ISSUER_MISMATCH, "Issuer mismatch");
+
+    return true;
+}
+
+
+/**
+ * Step 6.1.3.b-c.
+ */
+static bool rtCrX509CpvCheckNameConstraints(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    if (pThis->v.fNoPermittedSubtrees)
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_NO_PERMITTED_NAMES, "No permitted subtrees");
+
+    if (   pNode->pCert->TbsCertificate.Subject.cItems > 0
+        && (   !rtCrX509CpvIsNamePermitted(pThis, &pNode->pCert->TbsCertificate.Subject)
+            || rtCrX509CpvIsNameExcluded(pThis, &pNode->pCert->TbsCertificate.Subject)) )
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_NAME_NOT_PERMITTED,
+                                 "Subject name is not permitted by current name constraints");
+
+    PCRTCRX509GENERALNAMES pAltSubjectName = pNode->pCert->TbsCertificate.T3.pAltSubjectName;
+    if (pAltSubjectName)
+    {
+        uint32_t i = pAltSubjectName->cItems;
+        while (i-- > 0)
+            if (   !rtCrX509CpvIsGeneralNamePermitted(pThis, pAltSubjectName->papItems[i])
+                || rtCrX509CpvIsGeneralNameExcluded(pThis, pAltSubjectName->papItems[i]))
+                return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_ALT_NAME_NOT_PERMITTED,
+                                         "Alternative name #%u is is not permitted by current name constraints", i);
+    }
+
+    return true;
+}
+
+
+/**
+ * Step 6.1.3.d-f.
+ */
+static bool rtCrX509CpvWorkValidPolicyTree(PRTCRX509CERTPATHSINT pThis, uint32_t iDepth, PRTCRX509CERTPATHNODE pNode,
+                                           bool fSelfIssued)
+{
+    PCRTCRX509CERTIFICATEPOLICIES pPolicies = pNode->pCert->TbsCertificate.T3.pCertificatePolicies;
+    if (pPolicies)
+    {
+        /*
+         * 6.1.3.d.1 - Work the certiciate policies into the tree.
+         */
+        PRTCRX509CERTPATHSPOLICYNODE    pCur;
+        PRTLISTANCHOR                   pListAbove  = &pThis->v.paValidPolicyDepthLists[iDepth - 1];
+        uint32_t                        iAnyPolicy  = UINT32_MAX;
+        uint32_t                        i           = pPolicies->cItems;
+        while (i-- > 0)
+        {
+            PCRTCRX509POLICYQUALIFIERINFOS const    pQualifiers = &pPolicies->papItems[i]->PolicyQualifiers;
+            PCRTASN1OBJID const                     pIdP        = &pPolicies->papItems[i]->PolicyIdentifier;
+            if (RTAsn1ObjId_CompareWithString(pIdP, RTCRX509_ID_CE_CP_ANY_POLICY_OID) == 0)
+            {
+                iAnyPolicy++;
+                continue;
+            }
+
+            /*
+             * 6.1.3.d.1.i - Create children for matching policies.
+             */
+            uint32_t cMatches = 0;
+            RTListForEach(pListAbove, pCur, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+            {
+                bool fMatch = RTAsn1ObjId_Compare(pCur->pExpectedPolicyFirst, pIdP) == 0;
+                if (!fMatch && pCur->cMoreExpectedPolicySet)
+                    for (uint32_t j = 0; !fMatch && j < pCur->cMoreExpectedPolicySet; j++)
+                        fMatch = RTAsn1ObjId_Compare(pCur->papMoreExpectedPolicySet[j], pIdP) == 0;
+                if (fMatch)
+                {
+                    if (!rtCrX509CpvPolicyTreeInsertNew(pThis, pCur, iDepth, pIdP, pQualifiers, pIdP))
+                        return false;
+                    cMatches++;
+                }
+            }
+
+            /*
+             * 6.1.3.d.1.ii - If no matches above do the same for anyPolicy
+             *                nodes, only match with valid policy this time.
+             */
+            if (cMatches == 0)
+            {
+                RTListForEach(pListAbove, pCur, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+                {
+                    if (RTAsn1ObjId_CompareWithString(pCur->pExpectedPolicyFirst, RTCRX509_ID_CE_CP_ANY_POLICY_OID) == 0)
+                    {
+                        if (!rtCrX509CpvPolicyTreeInsertNew(pThis, pCur, iDepth, pIdP, pQualifiers, pIdP))
+                            return false;
+                    }
+                }
+            }
+        }
+
+        /*
+         * 6.1.3.d.2 - If anyPolicy present, make sure all expected policies
+         *             are propagated to the current depth.
+         */
+        if (   iAnyPolicy < pPolicies->cItems
+            && (   pThis->v.cInhibitAnyPolicy > 0
+                || (pNode->pParent && fSelfIssued) ) )
+        {
+            PCRTCRX509POLICYQUALIFIERINFOS pApQ = &pPolicies->papItems[iAnyPolicy]->PolicyQualifiers;
+            RTListForEach(pListAbove, pCur, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+            {
+                if (!rtCrX509CpvPolicyTreeIsChild(pCur, pCur->pExpectedPolicyFirst))
+                    rtCrX509CpvPolicyTreeInsertNew(pThis, pCur, iDepth, pCur->pExpectedPolicyFirst, pApQ,
+                                                   pCur->pExpectedPolicyFirst);
+                for (uint32_t j = 0; j < pCur->cMoreExpectedPolicySet; j++)
+                    if (!rtCrX509CpvPolicyTreeIsChild(pCur, pCur->papMoreExpectedPolicySet[j]))
+                        rtCrX509CpvPolicyTreeInsertNew(pThis, pCur, iDepth, pCur->papMoreExpectedPolicySet[j], pApQ,
+                                                       pCur->papMoreExpectedPolicySet[j]);
+            }
+        }
+        /*
+         * 6.1.3.d.3 - Prune the tree.
+         */
+        else
+            rtCrX509CpvPolicyTreePrune(pThis, iDepth - 1);
+    }
+    else
+    {
+        /*
+         * 6.1.3.e - No policy extension present, set tree to NULL.
+         */
+        rtCrX509CpvPolicyTreeDestroy(pThis);
+    }
+
+    /*
+     * 6.1.3.f - NULL tree check.
+     */
+    if (   pThis->v.pValidPolicyTree == NULL
+        && pThis->v.cExplicitPolicy == 0)
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_NO_VALID_POLICY,
+                                 "An explicit policy is called for but the valid policy tree is NULL.");
+    return RT_SUCCESS(pThis->rc);
+}
+
+
+/**
+ * Step 6.1.4.a-b.
+ */
+static bool rtCrX509CpvSoakUpPolicyMappings(PRTCRX509CERTPATHSINT pThis, uint32_t iDepth,
+                                            PCRTCRX509POLICYMAPPINGS pPolicyMappings)
+{
+    /*
+     * 6.1.4.a - The anyPolicy is not allowed in policy mappings as it would
+     *           allow an evil intermediate certificate to expand the policy
+     *           scope of a certiciate chain without regard to upstream.
+     */
+    uint32_t i = pPolicyMappings->cItems;
+    while (i-- > 0)
+    {
+        PCRTCRX509POLICYMAPPING const pOne = pPolicyMappings->papItems[i];
+        if (RTAsn1ObjId_CompareWithString(&pOne->IssuerDomainPolicy, RTCRX509_ID_CE_CP_ANY_POLICY_OID) == 0)
+            return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_INVALID_POLICY_MAPPING,
+                                     "Invalid policy mapping %#u: IssuerDomainPolicy is anyPolicy.", i);
+
+        if (RTAsn1ObjId_CompareWithString(&pOne->SubjectDomainPolicy, RTCRX509_ID_CE_CP_ANY_POLICY_OID) == 0)
+            return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_INVALID_POLICY_MAPPING,
+                                     "Invalid policy mapping %#u: SubjectDomainPolicy is anyPolicy.", i);
+    }
+
+    PRTCRX509CERTPATHSPOLICYNODE pCur, pNext;
+    if (pThis->v.cInhibitPolicyMapping > 0)
+    {
+        /*
+         * 6.1.4.b.1 - Do the policy mapping.
+         */
+        i = pPolicyMappings->cItems;
+        while (i-- > 0)
+        {
+            PCRTCRX509POLICYMAPPING const pOne = pPolicyMappings->papItems[i];
+
+            uint32_t cFound = 0;
+            RTListForEach(&pThis->v.paValidPolicyDepthLists[iDepth], pCur, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+            {
+                if (RTAsn1ObjId_Compare(pCur->pValidPolicy, &pOne->IssuerDomainPolicy))
+                {
+                    if (!pCur->fAlreadyMapped)
+                    {
+                        pCur->fAlreadyMapped = true;
+                        pCur->pExpectedPolicyFirst = &pOne->SubjectDomainPolicy;
+                    }
+                    else
+                    {
+                        uint32_t iExpected = pCur->cMoreExpectedPolicySet;
+                        void *pvNew = RTMemRealloc(pCur->papMoreExpectedPolicySet,
+                                                   sizeof(pCur->papMoreExpectedPolicySet[0]) * (iExpected + 1));
+                        if (!pvNew)
+                            return rtCrX509CpvFailed(pThis, VERR_NO_MEMORY,
+                                                     "Error growing papMoreExpectedPolicySet array (cur %u, depth %u)",
+                                                     pCur->cMoreExpectedPolicySet, iDepth);
+                        pCur->papMoreExpectedPolicySet = (PCRTASN1OBJID *)pvNew;
+                        pCur->papMoreExpectedPolicySet[iExpected] = &pOne->SubjectDomainPolicy;
+                        pCur->cMoreExpectedPolicySet = iExpected  + 1;
+                    }
+                    cFound++;
+                }
+            }
+
+            /*
+             * If no mapping took place, look for an anyPolicy node.
+             */
+            if (!cFound)
+            {
+                RTListForEach(&pThis->v.paValidPolicyDepthLists[iDepth], pCur, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+                {
+                    if (RTAsn1ObjId_CompareWithString(pCur->pValidPolicy, RTCRX509_ID_CE_CP_ANY_POLICY_OID) == 0)
+                    {
+                        if (!rtCrX509CpvPolicyTreeInsertNew(pThis, pCur->pParent, iDepth,
+                                                            &pOne->IssuerDomainPolicy,
+                                                            pCur->pPolicyQualifiers,
+                                                            &pOne->SubjectDomainPolicy))
+                            return false;
+                        break;
+                    }
+                }
+            }
+        }
+    }
+    else
+    {
+        /*
+         * 6.1.4.b.2 - Remove matching policies from the tree if mapping is
+         *             inhibited and prune the tree.
+         */
+        uint32_t cRemoved = 0;
+        i = pPolicyMappings->cItems;
+        while (i-- > 0)
+        {
+            PCRTCRX509POLICYMAPPING const pOne = pPolicyMappings->papItems[i];
+            RTListForEachSafe(&pThis->v.paValidPolicyDepthLists[iDepth], pCur, pNext, RTCRX509CERTPATHSPOLICYNODE, DepthEntry)
+            {
+                if (RTAsn1ObjId_Compare(pCur->pValidPolicy, &pOne->IssuerDomainPolicy))
+                {
+                    rtCrX509CpvPolicyTreeDestroyNode(pThis, pCur);
+                    cRemoved++;
+                }
+            }
+        }
+        if (cRemoved)
+            rtCrX509CpvPolicyTreePrune(pThis, iDepth - 1);
+    }
+
+    return true;
+}
+
+
+/**
+ * Step 6.1.4.d-f & 6.1.5.c-e.
+ */
+static void rtCrX509CpvSetWorkingPublicKeyInfo(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    PCRTCRX509TBSCERTIFICATE const pTbsCert = &pNode->pCert->TbsCertificate;
+
+    /*
+     * 6.1.4.d - The public key.
+     */
+    pThis->v.pWorkingPublicKey = &pTbsCert->SubjectPublicKeyInfo.SubjectPublicKey;
+
+    /*
+     * 6.1.4.e - The public key parameters.  Use new ones if present, keep old
+     *           if the algorithm remains the same.
+     */
+    if (   RTASN1CORE_IS_PRESENT(&pTbsCert->SubjectPublicKeyInfo.Algorithm.Parameters.u.Core)
+        && pTbsCert->SubjectPublicKeyInfo.Algorithm.Parameters.enmType != RTASN1TYPE_NULL)
+        pThis->v.pWorkingPublicKeyParameters = &pTbsCert->SubjectPublicKeyInfo.Algorithm.Parameters;
+    else if (   pThis->v.pWorkingPublicKeyParameters
+             && RTAsn1ObjId_Compare(pThis->v.pWorkingPublicKeyAlgorithm, &pTbsCert->SubjectPublicKeyInfo.Algorithm.Algorithm) != 0)
+        pThis->v.pWorkingPublicKeyParameters = NULL;
+
+    /*
+     * 6.1.4.f - The public algorithm.
+     */
+    pThis->v.pWorkingPublicKeyAlgorithm = &pTbsCert->SubjectPublicKeyInfo.Algorithm.Algorithm;
+}
+
+
+/**
+ * Step 6.1.4.g.
+ */
+static bool rtCrX509CpvSoakUpNameConstraints(PRTCRX509CERTPATHSINT pThis, PCRTCRX509NAMECONSTRAINTS pNameConstraints)
+{
+    if (pNameConstraints->T0.PermittedSubtrees.cItems > 0)
+        if (!rtCrX509CpvIntersectionPermittedSubtrees(pThis, &pNameConstraints->T0.PermittedSubtrees))
+            return false;
+
+    if (pNameConstraints->T1.ExcludedSubtrees.cItems > 0)
+        if (!rtCrX509CpvAddExcludedSubtrees(pThis, &pNameConstraints->T1.ExcludedSubtrees))
+            return false;
+
+    return true;
+}
+
+
+/**
+ * Step 6.1.4.i.
+ */
+static bool rtCrX509CpvSoakUpPolicyConstraints(PRTCRX509CERTPATHSINT pThis, PCRTCRX509POLICYCONSTRAINTS pPolicyConstraints)
+{
+    if (RTAsn1Integer_IsPresent(&pPolicyConstraints->RequireExplicitPolicy))
+    {
+        if (RTAsn1Integer_UnsignedCompareWithU32(&pPolicyConstraints->RequireExplicitPolicy, pThis->v.cExplicitPolicy) < 0)
+            pThis->v.cExplicitPolicy = pPolicyConstraints->RequireExplicitPolicy.uValue.s.Lo;
+    }
+
+    if (RTAsn1Integer_IsPresent(&pPolicyConstraints->InhibitPolicyMapping))
+    {
+        if (RTAsn1Integer_UnsignedCompareWithU32(&pPolicyConstraints->InhibitPolicyMapping, pThis->v.cInhibitPolicyMapping) < 0)
+            pThis->v.cInhibitPolicyMapping = pPolicyConstraints->InhibitPolicyMapping.uValue.s.Lo;
+    }
+    return true;
+}
+
+
+/**
+ * Step 6.1.4.j.
+ */
+static bool rtCrX509CpvSoakUpInhibitAnyPolicy(PRTCRX509CERTPATHSINT pThis, PCRTASN1INTEGER pInhibitAnyPolicy)
+{
+    if (RTAsn1Integer_UnsignedCompareWithU32(pInhibitAnyPolicy, pThis->v.cInhibitAnyPolicy) < 0)
+        pThis->v.cInhibitAnyPolicy = pInhibitAnyPolicy->uValue.s.Lo;
+    return true;
+}
+
+
+/**
+ * Steps 6.1.4.k, 6.1.4.l, 6.1.4.m, and 6.1.4.n.
+ */
+static bool rtCrX509CpvCheckAndSoakUpBasicConstraintsAndKeyUsage(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode,
+                                                                 bool fSelfIssued)
+{
+    /* 6.1.4.k - If basic constraints present, CA must be set. */
+    if (RTAsn1Integer_UnsignedCompareWithU32(&pNode->pCert->TbsCertificate.T0.Version, RTCRX509TBSCERTIFICATE_V3) != 0)
+    {
+        /* Note! Add flags if support for older certificates is needed later. */
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_NOT_V3_CERT,
+                                 "Only version 3 certificates are supported (Version=%llu)",
+                                 pNode->pCert->TbsCertificate.T0.Version.uValue);
+    }
+    PCRTCRX509BASICCONSTRAINTS pBasicConstraints = pNode->pCert->TbsCertificate.T3.pBasicConstraints;
+    if (pBasicConstraints)
+    {
+        if (!pBasicConstraints->CA.fValue)
+            return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_NOT_CA_CERT,
+                                     "Intermediate certificate (#%u) is not marked as a CA", pThis->v.iNode);
+    }
+
+    /* 6.1.4.l - Work cMaxPathLength. */
+    if (!fSelfIssued)
+    {
+        if (pThis->v.cMaxPathLength > 0)
+            pThis->v.cMaxPathLength--;
+        else
+            return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_MAX_PATH_LENGTH,
+                                     "Hit max path length at node #%u", pThis->v.iNode);
+    }
+
+    /* 6.1.4.m - Update cMaxPathLength if basic constrain field is present and smaller. */
+    if (pBasicConstraints)
+    {
+        if (RTAsn1Integer_IsPresent(&pBasicConstraints->PathLenConstraint))
+            if (RTAsn1Integer_UnsignedCompareWithU32(&pBasicConstraints->PathLenConstraint, pThis->v.cMaxPathLength) < 0)
+                pThis->v.cMaxPathLength = pBasicConstraints->PathLenConstraint.uValue.s.Lo;
+    }
+
+    /* 6.1.4.n - Require keyCertSign in key usage if the extension is present. */
+    PCRTCRX509TBSCERTIFICATE const pTbsCert = &pNode->pCert->TbsCertificate;
+    if (   (pTbsCert->T3.fFlags     & RTCRX509TBSCERTIFICATE_F_PRESENT_KEY_USAGE)
+        && !(pTbsCert->T3.fKeyUsage & RTCRX509CERT_KEY_USAGE_F_KEY_CERT_SIGN))
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_MISSING_KEY_CERT_SIGN,
+                                 "Node #%u does not have KeyCertSign set (keyUsage=%#x)",
+                                 pThis->v.iNode, pTbsCert->T3.fKeyUsage);
+
+    return true;
+}
+
+
+/**
+ * Step 6.1.4.o - check out critical extensions.
+ */
+static bool rtCrX509CpvCheckCriticalExtensions(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    uint32_t                  cLeft = pNode->pCert->TbsCertificate.T3.Extensions.cItems;
+    PRTCRX509EXTENSION const *ppCur = pNode->pCert->TbsCertificate.T3.Extensions.papItems;
+    while (cLeft-- > 0)
+    {
+        PCRTCRX509EXTENSION const pCur = *ppCur;
+        if (pCur->Critical.fValue)
+        {
+            if (   RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_KEY_USAGE_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_SUBJECT_ALT_NAME_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_ISSUER_ALT_NAME_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_BASIC_CONSTRAINTS_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_NAME_CONSTRAINTS_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_CERTIFICATE_POLICIES_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_POLICY_MAPPINGS_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_POLICY_CONSTRAINTS_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_EXT_KEY_USAGE_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCRX509_ID_CE_INHIBIT_ANY_POLICY_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCR_APPLE_CS_DEVID_APPLICATION_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCR_APPLE_CS_DEVID_INSTALLER_OID) != 0
+                && RTAsn1ObjId_CompareWithString(&pCur->ExtnId, RTCR_APPLE_CS_DEVID_KEXT_OID) != 0
+               )
+                return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_UNKNOWN_CRITICAL_EXTENSION,
+                                         "Node #%u has an unknown critical extension: %s", pThis->v.iNode, pCur->ExtnId.szObjId);
+        }
+
+        ppCur++;
+    }
+
+    return true;
+}
+
+
+/**
+ * Step 6.1.5 - The wrapping up.
+ */
+static bool rtCrX509CpvWrapUp(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pNode)
+{
+    Assert(!pNode->pParent); Assert(pThis->pTarget == pNode->pCert);
+
+    /*
+     * 6.1.5.a - Decrement explicit policy.
+     */
+    if (pThis->v.cExplicitPolicy > 0)
+        pThis->v.cExplicitPolicy--;
+
+    /*
+     * 6.1.5.b - Policy constraints and explicit policy.
+     */
+    PCRTCRX509POLICYCONSTRAINTS pPolicyConstraints = pNode->pCert->TbsCertificate.T3.pPolicyConstraints;
+    if (   pPolicyConstraints
+        && RTAsn1Integer_IsPresent(&pPolicyConstraints->RequireExplicitPolicy)
+        && RTAsn1Integer_UnsignedCompareWithU32(&pPolicyConstraints->RequireExplicitPolicy, 0) == 0)
+        pThis->v.cExplicitPolicy = 0;
+
+    /*
+     * 6.1.5.c-e - Update working public key info.
+     */
+    rtCrX509CpvSetWorkingPublicKeyInfo(pThis, pNode);
+
+    /*
+     * 6.1.5.f - Critical extensions.
+     */
+    if (!rtCrX509CpvCheckCriticalExtensions(pThis, pNode))
+        return false;
+
+    /*
+     * 6.1.5.g - Calculate the intersection between the user initial policy set
+     *           and the valid policy tree.
+     */
+    rtCrX509CpvPolicyTreeIntersect(pThis, pThis->cInitialUserPolicySet, pThis->papInitialUserPolicySet);
+
+    if (   pThis->v.cExplicitPolicy == 0
+        && pThis->v.pValidPolicyTree == NULL)
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CPV_NO_VALID_POLICY, "No valid policy (wrap-up).");
+
+    return true;
+}
+
+
+/**
+ * Worker that validates one path.
+ *
+ * This implements the algorithm in RFC-5280, section 6.1, with exception of
+ * the CRL checks in 6.1.3.a.3.
+ *
+ * @returns success indicator.
+ * @param   pThis           The path builder & validator instance.
+ * @param   pTrustAnchor    The trust anchor node.
+ */
+static bool rtCrX509CpvOneWorker(PRTCRX509CERTPATHSINT pThis, PRTCRX509CERTPATHNODE pTrustAnchor)
+{
+    /*
+     * Special case, target certificate is trusted.
+     */
+    if (!pTrustAnchor->pParent)
+        return rtCrX509CpvFailed(pThis, VERR_CR_X509_CERTPATHS_INTERNAL_ERROR, "Target certificate is trusted.");
+
+    /*
+     * Normal processing.
+     */
+    rtCrX509CpvInit(pThis, pTrustAnchor);
+    if (RT_SUCCESS(pThis->rc))
+    {
+        PRTCRX509CERTPATHNODE   pNode = pTrustAnchor->pParent;
+        uint32_t                iNode = pThis->v.iNode = 1; /* We count to cNode (inclusive).  Same a validation tree depth. */
+        while (pNode && RT_SUCCESS(pThis->rc))
+        {
+            /*
+             * Basic certificate processing.
+             */
+            if (!rtCrX509CpvCheckBasicCertInfo(pThis, pNode))                                           /* Step 6.1.3.a */
+                break;
+
+            bool const fSelfIssued = rtCrX509CertPathsIsSelfIssued(pNode);
+            if (!fSelfIssued || !pNode->pParent)                                                        /* Step 6.1.3.b-c */
+                if (!rtCrX509CpvCheckNameConstraints(pThis, pNode))
+                    break;
+
+            if (!rtCrX509CpvWorkValidPolicyTree(pThis, iNode, pNode, fSelfIssued))                      /* Step 6.1.3.d-f */
+                break;
+
+            /*
+             * If it's the last certificate in the path, do wrap-ups.
+             */
+            if (!pNode->pParent)                                                                         /* Step 6.1.5 */
+            {
+                Assert(iNode == pThis->v.cNodes);
+                if (!rtCrX509CpvWrapUp(pThis, pNode))
+                    break;
+                AssertRCBreak(pThis->rc);
+                return true;
+            }
+
+            /*
+             * Preparations for the next certificate.
+             */
+            PCRTCRX509TBSCERTIFICATE const pTbsCert = &pNode->pCert->TbsCertificate;
+            if (   pTbsCert->T3.pPolicyMappings
+                && !rtCrX509CpvSoakUpPolicyMappings(pThis, iNode, pTbsCert->T3.pPolicyMappings))        /* Step 6.1.4.a-b */
+                break;
+
+            pThis->v.pWorkingIssuer = &pTbsCert->Subject;                                               /* Step 6.1.4.c */
+
+            rtCrX509CpvSetWorkingPublicKeyInfo(pThis, pNode);                                           /* Step 6.1.4.d-f */
+
+            if (   pTbsCert->T3.pNameConstraints                                                        /* Step 6.1.4.g */
+                && !rtCrX509CpvSoakUpNameConstraints(pThis, pTbsCert->T3.pNameConstraints))
+                break;
+
+            if (!fSelfIssued)                                                                           /* Step 6.1.4.h */
+            {
+                if (pThis->v.cExplicitPolicy > 0)
+                    pThis->v.cExplicitPolicy--;
+                if (pThis->v.cInhibitPolicyMapping > 0)
+                    pThis->v.cInhibitPolicyMapping--;
+                if (pThis->v.cInhibitAnyPolicy > 0)
+                    pThis->v.cInhibitAnyPolicy--;
+            }
+
+            if (   pTbsCert->T3.pPolicyConstraints                                                      /* Step 6.1.4.j */
+                && !rtCrX509CpvSoakUpPolicyConstraints(pThis, pTbsCert->T3.pPolicyConstraints))
+                break;
+
+            if (   pTbsCert->T3.pInhibitAnyPolicy                                                       /* Step 6.1.4.j */
+                && !rtCrX509CpvSoakUpInhibitAnyPolicy(pThis, pTbsCert->T3.pInhibitAnyPolicy))
+                break;
+
+            if (!rtCrX509CpvCheckAndSoakUpBasicConstraintsAndKeyUsage(pThis, pNode, fSelfIssued))       /* Step 6.1.4.k-n */
+                break;
+
+            if (!rtCrX509CpvCheckCriticalExtensions(pThis, pNode))                                      /* Step 6.1.4.o */
+                break;
+
+            /*
+             * Advance to the next certificate.
+             */
+            pNode = pNode->pParent;
+            pThis->v.iNode = ++iNode;
+        }
+        AssertStmt(RT_FAILURE_NP(pThis->rc), pThis->rc = VERR_CR_X509_CERTPATHS_INTERNAL_ERROR);
+    }
+    return false;
+}
+
+
+RTDECL(int) RTCrX509CertPathsValidateOne(RTCRX509CERTPATHS hCertPaths, uint32_t iPath, PRTERRINFO pErrInfo)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertReturn(!(pThis->fFlags & ~RTCRX509CERTPATHSINT_F_VALID_MASK), VERR_INVALID_PARAMETER);
+    AssertPtrReturn(pThis->pTarget, VERR_INVALID_PARAMETER);
+    AssertPtrReturn(pThis->pRoot, VERR_INVALID_PARAMETER);
+    AssertReturn(pThis->rc == VINF_SUCCESS, VERR_INVALID_PARAMETER);
+
+    /*
+     * Locate the path and validate it.
+     */
+    int rc;
+    if (iPath < pThis->cPaths)
+    {
+        PRTCRX509CERTPATHNODE pLeaf = rtCrX509CertPathsGetLeafByIndex(pThis, iPath);
+        if (pLeaf)
+        {
+            if (RTCRX509CERTPATHNODE_SRC_IS_TRUSTED(pLeaf->uSrc))
+            {
+                pThis->pErrInfo = pErrInfo;
+                rtCrX509CpvOneWorker(pThis, pLeaf);
+                pThis->pErrInfo = NULL;
+                rc = pThis->rc;
+                pThis->rc = VINF_SUCCESS;
+            }
+            else
+                rc = RTErrInfoSetF(pErrInfo, VERR_CR_X509_NO_TRUST_ANCHOR, "Path #%u is does not have a trust anchor: uSrc=%s",
+                                   iPath, rtCrX509CertPathsNodeGetSourceName(pLeaf));
+            pLeaf->rcVerify = rc;
+        }
+        else
+            rc = VERR_CR_X509_CERTPATHS_INTERNAL_ERROR;
+    }
+    else
+        rc = VERR_NOT_FOUND;
+    return rc;
+}
+
+
+RTDECL(int) RTCrX509CertPathsValidateAll(RTCRX509CERTPATHS hCertPaths, uint32_t *pcValidPaths, PRTERRINFO pErrInfo)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertReturn(!(pThis->fFlags & ~RTCRX509CERTPATHSINT_F_VALID_MASK), VERR_INVALID_PARAMETER);
+    AssertPtrReturn(pThis->pTarget, VERR_INVALID_PARAMETER);
+    AssertPtrReturn(pThis->pRoot, VERR_INVALID_PARAMETER);
+    AssertReturn(pThis->rc == VINF_SUCCESS, VERR_INVALID_PARAMETER);
+    AssertPtrNullReturn(pcValidPaths, VERR_INVALID_POINTER);
+
+    /*
+     * Validate the paths.
+     */
+    pThis->pErrInfo = pErrInfo;
+
+    int      rcLastFailure = VINF_SUCCESS;
+    uint32_t cValidPaths   = 0;
+    PRTCRX509CERTPATHNODE pCurLeaf;
+    RTListForEach(&pThis->LeafList, pCurLeaf, RTCRX509CERTPATHNODE, ChildListOrLeafEntry)
+    {
+        if (RTCRX509CERTPATHNODE_SRC_IS_TRUSTED(pCurLeaf->uSrc))
+        {
+            rtCrX509CpvOneWorker(hCertPaths, pCurLeaf);
+            if (RT_SUCCESS(pThis->rc))
+                cValidPaths++;
+            else
+                rcLastFailure = pThis->rc;
+            pCurLeaf->rcVerify = pThis->rc;
+            pThis->rc = VINF_SUCCESS;
+        }
+        else
+            pCurLeaf->rcVerify = VERR_CR_X509_NO_TRUST_ANCHOR;
+    }
+
+    pThis->pErrInfo = NULL;
+
+    if (pcValidPaths)
+        *pcValidPaths = cValidPaths;
+    if (cValidPaths > 0)
+        return VINF_SUCCESS;
+    if (RT_SUCCESS_NP(rcLastFailure))
+        return RTErrInfoSetF(pErrInfo, VERR_CR_X509_CPV_NO_TRUSTED_PATHS,
+                             "None of the %u path(s) have a trust anchor.", pThis->cPaths);
+    return rcLastFailure;
+}
+
+
+RTDECL(uint32_t) RTCrX509CertPathsGetPathCount(RTCRX509CERTPATHS hCertPaths)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, UINT32_MAX);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, UINT32_MAX);
+    AssertPtrReturn(pThis->pRoot, UINT32_MAX);
+
+    /*
+     * Return data.
+     */
+    return pThis->cPaths;
+}
+
+
+RTDECL(int)  RTCrX509CertPathsQueryPathInfo(RTCRX509CERTPATHS hCertPaths, uint32_t iPath,
+                                            bool *pfTrusted, uint32_t *pcNodes, PCRTCRX509NAME *ppSubject,
+                                            PCRTCRX509SUBJECTPUBLICKEYINFO *ppPublicKeyInfo,
+                                            PCRTCRX509CERTIFICATE *ppCert, PCRTCRCERTCTX *ppCertCtx,
+                                            int *prcVerify)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertPtrReturn(pThis->pRoot, VERR_WRONG_ORDER);
+    AssertReturn(iPath < pThis->cPaths, VERR_NOT_FOUND);
+
+    /*
+     * Get the data.
+     */
+    PRTCRX509CERTPATHNODE pLeaf = rtCrX509CertPathsGetLeafByIndex(pThis, iPath);
+    AssertReturn(pLeaf, VERR_CR_X509_INTERNAL_ERROR);
+
+    if (pfTrusted)
+        *pfTrusted = RTCRX509CERTPATHNODE_SRC_IS_TRUSTED(pLeaf->uSrc);
+
+    if (pcNodes)
+        *pcNodes = pLeaf->uDepth + 1; /* Includes both trust anchor and target. */
+
+    if (ppSubject)
+        *ppSubject = pLeaf->pCert ? &pLeaf->pCert->TbsCertificate.Subject : &pLeaf->pCertCtx->pTaInfo->CertPath.TaName;
+
+    if (ppPublicKeyInfo)
+        *ppPublicKeyInfo = pLeaf->pCert ? &pLeaf->pCert->TbsCertificate.SubjectPublicKeyInfo : &pLeaf->pCertCtx->pTaInfo->PubKey;
+
+    if (ppCert)
+        *ppCert = pLeaf->pCert;
+
+    if (ppCertCtx)
+    {
+        if (pLeaf->pCertCtx)
+        {
+            uint32_t cRefs = RTCrCertCtxRetain(pLeaf->pCertCtx);
+            AssertReturn(cRefs != UINT32_MAX, VERR_CR_X509_INTERNAL_ERROR);
+        }
+        *ppCertCtx = pLeaf->pCertCtx;
+    }
+
+    if (prcVerify)
+        *prcVerify = pLeaf->rcVerify;
+
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(uint32_t) RTCrX509CertPathsGetPathLength(RTCRX509CERTPATHS hCertPaths, uint32_t iPath)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, UINT32_MAX);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, UINT32_MAX);
+    AssertPtrReturn(pThis->pRoot, UINT32_MAX);
+    AssertReturn(iPath < pThis->cPaths, UINT32_MAX);
+
+    /*
+     * Get the data.
+     */
+    PRTCRX509CERTPATHNODE pLeaf = rtCrX509CertPathsGetLeafByIndex(pThis, iPath);
+    AssertReturn(pLeaf, UINT32_MAX);
+    return pLeaf->uDepth + 1;
+}
+
+
+RTDECL(int) RTCrX509CertPathsGetPathVerifyResult(RTCRX509CERTPATHS hCertPaths, uint32_t iPath)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, VERR_INVALID_HANDLE);
+    AssertPtrReturn(pThis->pRoot, VERR_WRONG_ORDER);
+    AssertReturn(iPath < pThis->cPaths, VERR_NOT_FOUND);
+
+    /*
+     * Get the data.
+     */
+    PRTCRX509CERTPATHNODE pLeaf = rtCrX509CertPathsGetLeafByIndex(pThis, iPath);
+    AssertReturn(pLeaf, VERR_CR_X509_INTERNAL_ERROR);
+
+    return pLeaf->rcVerify;
+}
+
+
+static PRTCRX509CERTPATHNODE rtCrX509CertPathsGetPathNodeByIndexes(PRTCRX509CERTPATHSINT pThis, uint32_t iPath, uint32_t iNode)
+{
+    PRTCRX509CERTPATHNODE pNode = rtCrX509CertPathsGetLeafByIndex(pThis, iPath);
+    Assert(pNode);
+    if (pNode)
+    {
+        if (iNode <= pNode->uDepth)
+        {
+            uint32_t uCertDepth = pNode->uDepth - iNode;
+            while (pNode->uDepth > uCertDepth)
+                pNode = pNode->pParent;
+            Assert(pNode);
+            Assert(pNode && pNode->uDepth == uCertDepth);
+            return pNode;
+        }
+    }
+
+    return NULL;
+}
+
+
+RTDECL(PCRTCRX509CERTIFICATE) RTCrX509CertPathsGetPathNodeCert(RTCRX509CERTPATHS hCertPaths, uint32_t iPath, uint32_t iNode)
+{
+    /*
+     * Validate the input.
+     */
+    PRTCRX509CERTPATHSINT pThis = hCertPaths;
+    AssertPtrReturn(pThis, NULL);
+    AssertReturn(pThis->u32Magic == RTCRX509CERTPATHSINT_MAGIC, NULL);
+    AssertPtrReturn(pThis->pRoot, NULL);
+    AssertReturn(iPath < pThis->cPaths, NULL);
+
+    /*
+     * Get the data.
+     */
+    PRTCRX509CERTPATHNODE pNode = rtCrX509CertPathsGetPathNodeByIndexes(pThis, iPath, iNode);
+    if (pNode)
+        return pNode->pCert;
+    return NULL;
+}
+
+
+/** @} */
+