Sweden-Number/dlls/crypt32/chain.c

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/*
* Copyright 2006 Juan Lang
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
*
*/
#include <stdarg.h>
#include "windef.h"
#include "winbase.h"
#include "wincrypt.h"
#include "wine/debug.h"
#include "crypt32_private.h"
WINE_DEFAULT_DEBUG_CHANNEL(crypt);
#define DEFAULT_CYCLE_MODULUS 7
static HCERTCHAINENGINE CRYPT_defaultChainEngine;
/* This represents a subset of a certificate chain engine: it doesn't include
* the "hOther" store described by MSDN, because I'm not sure how that's used.
* It also doesn't include the "hTrust" store, because I don't yet implement
* CTLs or complex certificate chains.
*/
typedef struct _CertificateChainEngine
{
LONG ref;
HCERTSTORE hRoot;
HCERTSTORE hWorld;
DWORD dwFlags;
DWORD dwUrlRetrievalTimeout;
DWORD MaximumCachedCertificates;
DWORD CycleDetectionModulus;
} CertificateChainEngine, *PCertificateChainEngine;
static inline void CRYPT_AddStoresToCollection(HCERTSTORE collection,
DWORD cStores, HCERTSTORE *stores)
{
DWORD i;
for (i = 0; i < cStores; i++)
CertAddStoreToCollection(collection, stores[i], 0, 0);
}
static inline void CRYPT_CloseStores(DWORD cStores, HCERTSTORE *stores)
{
DWORD i;
for (i = 0; i < cStores; i++)
CertCloseStore(stores[i], 0);
}
static const WCHAR rootW[] = { 'R','o','o','t',0 };
static BOOL CRYPT_CheckRestrictedRoot(HCERTSTORE store)
{
BOOL ret = TRUE;
if (store)
{
HCERTSTORE rootStore = CertOpenSystemStoreW(0, rootW);
PCCERT_CONTEXT cert = NULL, check;
BYTE hash[20];
DWORD size;
do {
cert = CertEnumCertificatesInStore(store, cert);
if (cert)
{
size = sizeof(hash);
ret = CertGetCertificateContextProperty(cert, CERT_HASH_PROP_ID,
hash, &size);
if (ret)
{
CRYPT_HASH_BLOB blob = { sizeof(hash), hash };
check = CertFindCertificateInStore(rootStore,
cert->dwCertEncodingType, 0, CERT_FIND_SHA1_HASH, &blob,
NULL);
if (!check)
ret = FALSE;
else
CertFreeCertificateContext(check);
}
}
} while (ret && cert);
if (cert)
CertFreeCertificateContext(cert);
CertCloseStore(rootStore, 0);
}
return ret;
}
HCERTCHAINENGINE CRYPT_CreateChainEngine(HCERTSTORE root,
PCERT_CHAIN_ENGINE_CONFIG pConfig)
{
static const WCHAR caW[] = { 'C','A',0 };
static const WCHAR myW[] = { 'M','y',0 };
static const WCHAR trustW[] = { 'T','r','u','s','t',0 };
PCertificateChainEngine engine =
CryptMemAlloc(sizeof(CertificateChainEngine));
if (engine)
{
HCERTSTORE worldStores[4];
engine->ref = 1;
engine->hRoot = root;
engine->hWorld = CertOpenStore(CERT_STORE_PROV_COLLECTION, 0, 0,
CERT_STORE_CREATE_NEW_FLAG, NULL);
worldStores[0] = CertDuplicateStore(engine->hRoot);
worldStores[1] = CertOpenSystemStoreW(0, caW);
worldStores[2] = CertOpenSystemStoreW(0, myW);
worldStores[3] = CertOpenSystemStoreW(0, trustW);
CRYPT_AddStoresToCollection(engine->hWorld,
sizeof(worldStores) / sizeof(worldStores[0]), worldStores);
CRYPT_AddStoresToCollection(engine->hWorld,
pConfig->cAdditionalStore, pConfig->rghAdditionalStore);
CRYPT_CloseStores(sizeof(worldStores) / sizeof(worldStores[0]),
worldStores);
engine->dwFlags = pConfig->dwFlags;
engine->dwUrlRetrievalTimeout = pConfig->dwUrlRetrievalTimeout;
engine->MaximumCachedCertificates =
pConfig->MaximumCachedCertificates;
if (pConfig->CycleDetectionModulus)
engine->CycleDetectionModulus = pConfig->CycleDetectionModulus;
else
engine->CycleDetectionModulus = DEFAULT_CYCLE_MODULUS;
}
return (HCERTCHAINENGINE)engine;
}
BOOL WINAPI CertCreateCertificateChainEngine(PCERT_CHAIN_ENGINE_CONFIG pConfig,
HCERTCHAINENGINE *phChainEngine)
{
BOOL ret;
TRACE("(%p, %p)\n", pConfig, phChainEngine);
if (pConfig->cbSize != sizeof(*pConfig))
{
SetLastError(E_INVALIDARG);
return FALSE;
}
*phChainEngine = NULL;
ret = CRYPT_CheckRestrictedRoot(pConfig->hRestrictedRoot);
if (ret)
{
HCERTSTORE root;
HCERTCHAINENGINE engine;
if (pConfig->hRestrictedRoot)
root = CertDuplicateStore(pConfig->hRestrictedRoot);
else
root = CertOpenSystemStoreW(0, rootW);
engine = CRYPT_CreateChainEngine(root, pConfig);
if (engine)
{
*phChainEngine = engine;
ret = TRUE;
}
else
ret = FALSE;
}
return ret;
}
VOID WINAPI CertFreeCertificateChainEngine(HCERTCHAINENGINE hChainEngine)
{
PCertificateChainEngine engine = (PCertificateChainEngine)hChainEngine;
TRACE("(%p)\n", hChainEngine);
if (engine && InterlockedDecrement(&engine->ref) == 0)
{
CertCloseStore(engine->hWorld, 0);
CertCloseStore(engine->hRoot, 0);
CryptMemFree(engine);
}
}
static HCERTCHAINENGINE CRYPT_GetDefaultChainEngine(void)
{
if (!CRYPT_defaultChainEngine)
{
CERT_CHAIN_ENGINE_CONFIG config = { 0 };
HCERTCHAINENGINE engine;
config.cbSize = sizeof(config);
CertCreateCertificateChainEngine(&config, &engine);
InterlockedCompareExchangePointer(&CRYPT_defaultChainEngine, engine,
NULL);
if (CRYPT_defaultChainEngine != engine)
CertFreeCertificateChainEngine(engine);
}
return CRYPT_defaultChainEngine;
}
void default_chain_engine_free(void)
{
CertFreeCertificateChainEngine(CRYPT_defaultChainEngine);
}
typedef struct _CertificateChain
{
CERT_CHAIN_CONTEXT context;
2007-09-06 18:59:19 +02:00
HCERTSTORE world;
LONG ref;
} CertificateChain, *PCertificateChain;
static inline BOOL CRYPT_IsCertificateSelfSigned(PCCERT_CONTEXT cert)
{
return CertCompareCertificateName(cert->dwCertEncodingType,
&cert->pCertInfo->Subject, &cert->pCertInfo->Issuer);
}
static void CRYPT_FreeChainElement(PCERT_CHAIN_ELEMENT element)
{
CertFreeCertificateContext(element->pCertContext);
CryptMemFree(element);
}
static void CRYPT_CheckSimpleChainForCycles(PCERT_SIMPLE_CHAIN chain)
{
DWORD i, j, cyclicCertIndex = 0;
/* O(n^2) - I don't think there's a faster way */
for (i = 0; !cyclicCertIndex && i < chain->cElement; i++)
for (j = i + 1; !cyclicCertIndex && j < chain->cElement; j++)
if (CertCompareCertificate(X509_ASN_ENCODING,
chain->rgpElement[i]->pCertContext->pCertInfo,
chain->rgpElement[j]->pCertContext->pCertInfo))
cyclicCertIndex = j;
if (cyclicCertIndex)
{
chain->rgpElement[cyclicCertIndex]->TrustStatus.dwErrorStatus
|= CERT_TRUST_IS_CYCLIC;
/* Release remaining certs */
for (i = cyclicCertIndex + 1; i < chain->cElement; i++)
CRYPT_FreeChainElement(chain->rgpElement[i]);
/* Truncate chain */
chain->cElement = cyclicCertIndex + 1;
}
}
/* Checks whether the chain is cyclic by examining the last element's status */
static inline BOOL CRYPT_IsSimpleChainCyclic(PCERT_SIMPLE_CHAIN chain)
{
if (chain->cElement)
return chain->rgpElement[chain->cElement - 1]->TrustStatus.dwErrorStatus
& CERT_TRUST_IS_CYCLIC;
else
return FALSE;
}
static inline void CRYPT_CombineTrustStatus(CERT_TRUST_STATUS *chainStatus,
CERT_TRUST_STATUS *elementStatus)
{
/* Any error that applies to an element also applies to a chain.. */
chainStatus->dwErrorStatus |= elementStatus->dwErrorStatus;
/* but the bottom nibble of an element's info status doesn't apply to the
* chain.
*/
chainStatus->dwInfoStatus |= (elementStatus->dwInfoStatus & 0xfffffff0);
}
static BOOL CRYPT_AddCertToSimpleChain(PCertificateChainEngine engine,
PCERT_SIMPLE_CHAIN chain, PCCERT_CONTEXT cert)
{
BOOL ret = FALSE;
PCERT_CHAIN_ELEMENT element = CryptMemAlloc(sizeof(CERT_CHAIN_ELEMENT));
if (element)
{
if (!chain->cElement)
chain->rgpElement = CryptMemAlloc(sizeof(PCERT_CHAIN_ELEMENT));
else
chain->rgpElement = CryptMemRealloc(chain->rgpElement,
(chain->cElement + 1) * sizeof(PCERT_CHAIN_ELEMENT));
if (chain->rgpElement)
{
chain->rgpElement[chain->cElement++] = element;
memset(element, 0, sizeof(CERT_CHAIN_ELEMENT));
element->cbSize = sizeof(CERT_CHAIN_ELEMENT);
element->pCertContext = CertDuplicateCertificateContext(cert);
/* FIXME: initialize the rest of element */
if (chain->cElement % engine->CycleDetectionModulus)
CRYPT_CheckSimpleChainForCycles(chain);
CRYPT_CombineTrustStatus(&chain->TrustStatus,
&element->TrustStatus);
ret = TRUE;
}
else
CryptMemFree(element);
}
return ret;
}
static void CRYPT_FreeSimpleChain(PCERT_SIMPLE_CHAIN chain)
{
DWORD i;
for (i = 0; i < chain->cElement; i++)
CRYPT_FreeChainElement(chain->rgpElement[i]);
CryptMemFree(chain->rgpElement);
CryptMemFree(chain);
}
static void CRYPT_CheckTrustedStatus(HCERTSTORE hRoot,
PCERT_CHAIN_ELEMENT rootElement)
{
BYTE hash[20];
DWORD size = sizeof(hash);
CRYPT_HASH_BLOB blob = { sizeof(hash), hash };
PCCERT_CONTEXT trustedRoot;
CertGetCertificateContextProperty(rootElement->pCertContext,
CERT_HASH_PROP_ID, hash, &size);
trustedRoot = CertFindCertificateInStore(hRoot,
rootElement->pCertContext->dwCertEncodingType, 0, CERT_FIND_SHA1_HASH,
&blob, NULL);
if (!trustedRoot)
rootElement->TrustStatus.dwErrorStatus |=
CERT_TRUST_IS_UNTRUSTED_ROOT;
else
CertFreeCertificateContext(trustedRoot);
}
static void CRYPT_CheckRootCert(HCERTCHAINENGINE hRoot,
PCERT_CHAIN_ELEMENT rootElement)
{
PCCERT_CONTEXT root = rootElement->pCertContext;
if (!CryptVerifyCertificateSignatureEx(0, root->dwCertEncodingType,
CRYPT_VERIFY_CERT_SIGN_SUBJECT_CERT, (void *)root,
CRYPT_VERIFY_CERT_SIGN_ISSUER_CERT, (void *)root, 0, NULL))
{
TRACE("Last certificate's signature is invalid\n");
rootElement->TrustStatus.dwErrorStatus |=
CERT_TRUST_IS_NOT_SIGNATURE_VALID;
}
CRYPT_CheckTrustedStatus(hRoot, rootElement);
}
/* Decodes a cert's basic constraints extension (either szOID_BASIC_CONSTRAINTS
* or szOID_BASIC_CONSTRAINTS2, whichever is present) into a
* CERT_BASIC_CONSTRAINTS2_INFO. If it neither extension is present, sets
* constraints->fCA to defaultIfNotSpecified.
* Returns FALSE if the extension is present but couldn't be decoded.
*/
static BOOL CRYPT_DecodeBasicConstraints(PCCERT_CONTEXT cert,
CERT_BASIC_CONSTRAINTS2_INFO *constraints, BOOL defaultIfNotSpecified)
{
BOOL ret = TRUE;
PCERT_EXTENSION ext = CertFindExtension(szOID_BASIC_CONSTRAINTS,
cert->pCertInfo->cExtension, cert->pCertInfo->rgExtension);
constraints->fPathLenConstraint = FALSE;
if (ext)
{
CERT_BASIC_CONSTRAINTS_INFO *info;
DWORD size = 0;
ret = CryptDecodeObjectEx(X509_ASN_ENCODING, szOID_BASIC_CONSTRAINTS,
ext->Value.pbData, ext->Value.cbData, CRYPT_DECODE_ALLOC_FLAG,
NULL, (LPBYTE)&info, &size);
if (ret)
{
if (info->SubjectType.cbData == 1)
constraints->fCA =
info->SubjectType.pbData[0] & CERT_CA_SUBJECT_FLAG;
LocalFree(info);
}
}
else
{
ext = CertFindExtension(szOID_BASIC_CONSTRAINTS2,
cert->pCertInfo->cExtension, cert->pCertInfo->rgExtension);
if (ext)
{
DWORD size = sizeof(CERT_BASIC_CONSTRAINTS2_INFO);
ret = CryptDecodeObjectEx(X509_ASN_ENCODING,
szOID_BASIC_CONSTRAINTS2, ext->Value.pbData, ext->Value.cbData,
0, NULL, constraints, &size);
}
else
constraints->fCA = defaultIfNotSpecified;
}
return ret;
}
/* Checks element's basic constraints to see if it can act as a CA, with
* remainingCAs CAs left in this chain. Updates chainConstraints with the
* element's constraints, if:
* 1. chainConstraints doesn't have a path length constraint, or
* 2. element's path length constraint is smaller than chainConstraints's
* Sets *pathLengthConstraintViolated to TRUE if a path length violation
* occurs.
* Returns TRUE if the element can be a CA, and the length of the remaining
* chain is valid.
*/
static BOOL CRYPT_CheckBasicConstraintsForCA(PCCERT_CONTEXT cert,
CERT_BASIC_CONSTRAINTS2_INFO *chainConstraints, DWORD remainingCAs,
BOOL *pathLengthConstraintViolated)
{
BOOL validBasicConstraints;
CERT_BASIC_CONSTRAINTS2_INFO constraints;
if ((validBasicConstraints = CRYPT_DecodeBasicConstraints(cert,
&constraints, TRUE)))
{
if (!constraints.fCA)
{
TRACE("chain element %d can't be a CA\n", remainingCAs + 1);
validBasicConstraints = FALSE;
}
else if (constraints.fPathLenConstraint)
{
/* If the element has path length constraints, they apply to the
* entire remaining chain.
*/
if (!chainConstraints->fPathLenConstraint ||
constraints.dwPathLenConstraint <
chainConstraints->dwPathLenConstraint)
{
TRACE("setting path length constraint to %d\n",
chainConstraints->dwPathLenConstraint);
chainConstraints->fPathLenConstraint = TRUE;
chainConstraints->dwPathLenConstraint =
constraints.dwPathLenConstraint;
}
}
}
if (chainConstraints->fPathLenConstraint &&
remainingCAs > chainConstraints->dwPathLenConstraint)
{
TRACE("remaining CAs %d exceed max path length %d\n", remainingCAs,
chainConstraints->dwPathLenConstraint);
validBasicConstraints = FALSE;
*pathLengthConstraintViolated = TRUE;
}
return validBasicConstraints;
}
static void CRYPT_CheckSimpleChain(PCertificateChainEngine engine,
PCERT_SIMPLE_CHAIN chain, LPFILETIME time)
{
PCERT_CHAIN_ELEMENT rootElement = chain->rgpElement[chain->cElement - 1];
int i;
BOOL pathLengthConstraintViolated = FALSE;
CERT_BASIC_CONSTRAINTS2_INFO constraints = { TRUE, FALSE, 0 };
for (i = chain->cElement - 1; i >= 0; i--)
{
if (CertVerifyTimeValidity(time,
chain->rgpElement[i]->pCertContext->pCertInfo) != 0)
chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
CERT_TRUST_IS_NOT_TIME_VALID;
if (i != 0)
{
/* Check the signature of the cert this issued */
if (!CryptVerifyCertificateSignatureEx(0, X509_ASN_ENCODING,
CRYPT_VERIFY_CERT_SIGN_SUBJECT_CERT,
(void *)chain->rgpElement[i - 1]->pCertContext,
CRYPT_VERIFY_CERT_SIGN_ISSUER_CERT,
(void *)chain->rgpElement[i]->pCertContext, 0, NULL))
chain->rgpElement[i - 1]->TrustStatus.dwErrorStatus |=
CERT_TRUST_IS_NOT_SIGNATURE_VALID;
/* Once a path length constraint has been violated, every remaining
* CA cert's basic constraints is considered invalid.
*/
if (pathLengthConstraintViolated)
chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
CERT_TRUST_INVALID_BASIC_CONSTRAINTS;
else if (!CRYPT_CheckBasicConstraintsForCA(
chain->rgpElement[i]->pCertContext, &constraints, i - 1,
&pathLengthConstraintViolated))
chain->rgpElement[i]->TrustStatus.dwErrorStatus |=
CERT_TRUST_INVALID_BASIC_CONSTRAINTS;
else if (constraints.fPathLenConstraint &&
constraints.dwPathLenConstraint)
{
/* This one's valid - decrement max length */
constraints.dwPathLenConstraint--;
}
}
/* FIXME: check valid usages and name constraints */
CRYPT_CombineTrustStatus(&chain->TrustStatus,
&chain->rgpElement[i]->TrustStatus);
}
if (CRYPT_IsCertificateSelfSigned(rootElement->pCertContext))
{
rootElement->TrustStatus.dwInfoStatus |= CERT_TRUST_IS_SELF_SIGNED;
CRYPT_CheckRootCert(engine->hRoot, rootElement);
}
/* FIXME: check revocation of every cert with CertVerifyRevocation */
CRYPT_CombineTrustStatus(&chain->TrustStatus, &rootElement->TrustStatus);
}
static PCCERT_CONTEXT CRYPT_GetIssuer(HCERTSTORE store, PCCERT_CONTEXT subject,
PCCERT_CONTEXT prevIssuer)
{
PCCERT_CONTEXT issuer;
DWORD flags = 0;
issuer = CertGetIssuerCertificateFromStore(store, subject, prevIssuer,
&flags);
return issuer;
}
/* Builds a simple chain by finding an issuer for the last cert in the chain,
* until reaching a self-signed cert, or until no issuer can be found.
*/
static BOOL CRYPT_BuildSimpleChain(PCertificateChainEngine engine,
HCERTSTORE world, PCERT_SIMPLE_CHAIN chain)
{
BOOL ret = TRUE;
PCCERT_CONTEXT cert = chain->rgpElement[chain->cElement - 1]->pCertContext;
while (ret && !CRYPT_IsSimpleChainCyclic(chain) &&
!CRYPT_IsCertificateSelfSigned(cert))
{
PCCERT_CONTEXT issuer = CRYPT_GetIssuer(world, cert, NULL);
if (issuer)
{
ret = CRYPT_AddCertToSimpleChain(engine, chain, issuer);
cert = issuer;
}
else
{
TRACE("Couldn't find issuer, halting chain creation\n");
break;
}
}
return ret;
}
static BOOL CRYPT_GetSimpleChainForCert(PCertificateChainEngine engine,
HCERTSTORE world, PCCERT_CONTEXT cert, LPFILETIME pTime,
PCERT_SIMPLE_CHAIN *ppChain)
{
BOOL ret = FALSE;
PCERT_SIMPLE_CHAIN chain;
TRACE("(%p, %p, %p, %p)\n", engine, world, cert, pTime);
chain = CryptMemAlloc(sizeof(CERT_SIMPLE_CHAIN));
if (chain)
{
memset(chain, 0, sizeof(CERT_SIMPLE_CHAIN));
chain->cbSize = sizeof(CERT_SIMPLE_CHAIN);
ret = CRYPT_AddCertToSimpleChain(engine, chain, cert);
if (ret)
{
ret = CRYPT_BuildSimpleChain(engine, world, chain);
if (ret)
CRYPT_CheckSimpleChain(engine, chain, pTime);
}
if (!ret)
{
CRYPT_FreeSimpleChain(chain);
chain = NULL;
}
*ppChain = chain;
}
return ret;
}
static BOOL CRYPT_BuildCandidateChainFromCert(HCERTCHAINENGINE hChainEngine,
PCCERT_CONTEXT cert, LPFILETIME pTime, HCERTSTORE hAdditionalStore,
PCertificateChain *ppChain)
{
PCertificateChainEngine engine = (PCertificateChainEngine)hChainEngine;
PCERT_SIMPLE_CHAIN simpleChain = NULL;
HCERTSTORE world;
BOOL ret;
world = CertOpenStore(CERT_STORE_PROV_COLLECTION, 0, 0,
CERT_STORE_CREATE_NEW_FLAG, NULL);
CertAddStoreToCollection(world, engine->hWorld, 0, 0);
if (hAdditionalStore)
CertAddStoreToCollection(world, hAdditionalStore, 0, 0);
/* FIXME: only simple chains are supported for now, as CTLs aren't
* supported yet.
*/
if ((ret = CRYPT_GetSimpleChainForCert(engine, world, cert, pTime,
&simpleChain)))
{
PCertificateChain chain = CryptMemAlloc(sizeof(CertificateChain));
if (chain)
{
chain->ref = 1;
2007-09-06 18:59:19 +02:00
chain->world = world;
chain->context.cbSize = sizeof(CERT_CHAIN_CONTEXT);
memcpy(&chain->context.TrustStatus, &simpleChain->TrustStatus,
sizeof(CERT_TRUST_STATUS));
chain->context.cChain = 1;
chain->context.rgpChain = CryptMemAlloc(sizeof(PCERT_SIMPLE_CHAIN));
chain->context.rgpChain[0] = simpleChain;
chain->context.cLowerQualityChainContext = 0;
chain->context.rgpLowerQualityChainContext = NULL;
chain->context.fHasRevocationFreshnessTime = FALSE;
chain->context.dwRevocationFreshnessTime = 0;
}
else
ret = FALSE;
*ppChain = chain;
}
return ret;
}
/* Makes and returns a copy of chain, up to and including element iElement. */
static PCERT_SIMPLE_CHAIN CRYPT_CopySimpleChainToElement(
PCERT_SIMPLE_CHAIN chain, DWORD iElement)
{
PCERT_SIMPLE_CHAIN copy = CryptMemAlloc(sizeof(CERT_SIMPLE_CHAIN));
if (copy)
{
memset(copy, 0, sizeof(CERT_SIMPLE_CHAIN));
copy->cbSize = sizeof(CERT_SIMPLE_CHAIN);
copy->rgpElement =
CryptMemAlloc((iElement + 1) * sizeof(PCERT_CHAIN_ELEMENT));
if (copy->rgpElement)
{
DWORD i;
BOOL ret = TRUE;
memset(copy->rgpElement, 0,
(iElement + 1) * sizeof(PCERT_CHAIN_ELEMENT));
for (i = 0; ret && i <= iElement; i++)
{
PCERT_CHAIN_ELEMENT element =
CryptMemAlloc(sizeof(CERT_CHAIN_ELEMENT));
if (element)
{
memcpy(element, chain->rgpElement[i],
sizeof(CERT_CHAIN_ELEMENT));
element->pCertContext = CertDuplicateCertificateContext(
chain->rgpElement[i]->pCertContext);
/* Reset the trust status of the copied element, it'll get
* rechecked after the new chain is done.
*/
memset(&element->TrustStatus, 0, sizeof(CERT_TRUST_STATUS));
copy->rgpElement[copy->cElement++] = element;
}
else
ret = FALSE;
}
if (!ret)
{
for (i = 0; i <= iElement; i++)
CryptMemFree(copy->rgpElement[i]);
CryptMemFree(copy->rgpElement);
CryptMemFree(copy);
copy = NULL;
}
}
else
{
CryptMemFree(copy);
copy = NULL;
}
}
return copy;
}
static void CRYPT_FreeLowerQualityChains(PCertificateChain chain)
{
DWORD i;
for (i = 0; i < chain->context.cLowerQualityChainContext; i++)
CertFreeCertificateChain(chain->context.rgpLowerQualityChainContext[i]);
CryptMemFree(chain->context.rgpLowerQualityChainContext);
}
static void CRYPT_FreeChainContext(PCertificateChain chain)
{
DWORD i;
CRYPT_FreeLowerQualityChains(chain);
for (i = 0; i < chain->context.cChain; i++)
CRYPT_FreeSimpleChain(chain->context.rgpChain[i]);
CryptMemFree(chain->context.rgpChain);
CertCloseStore(chain->world, 0);
CryptMemFree(chain);
}
/* Makes and returns a copy of chain, up to and including element iElement of
* simple chain iChain.
*/
static PCertificateChain CRYPT_CopyChainToElement(PCertificateChain chain,
DWORD iChain, DWORD iElement)
{
PCertificateChain copy = CryptMemAlloc(sizeof(CertificateChain));
if (copy)
{
copy->ref = 1;
copy->world = CertDuplicateStore(chain->world);
copy->context.cbSize = sizeof(CERT_CHAIN_CONTEXT);
/* Leave the trust status of the copied chain unset, it'll get
* rechecked after the new chain is done.
*/
memset(&copy->context.TrustStatus, 0, sizeof(CERT_TRUST_STATUS));
copy->context.cLowerQualityChainContext = 0;
copy->context.rgpLowerQualityChainContext = NULL;
copy->context.fHasRevocationFreshnessTime = FALSE;
copy->context.dwRevocationFreshnessTime = 0;
copy->context.rgpChain = CryptMemAlloc(
(iChain + 1) * sizeof(PCERT_SIMPLE_CHAIN));
if (copy->context.rgpChain)
{
BOOL ret = TRUE;
DWORD i;
memset(copy->context.rgpChain, 0,
(iChain + 1) * sizeof(PCERT_SIMPLE_CHAIN));
if (iChain)
{
for (i = 0; ret && iChain && i < iChain - 1; i++)
{
copy->context.rgpChain[i] =
CRYPT_CopySimpleChainToElement(chain->context.rgpChain[i],
chain->context.rgpChain[i]->cElement - 1);
if (!copy->context.rgpChain[i])
ret = FALSE;
}
}
else
i = 0;
if (ret)
{
copy->context.rgpChain[i] =
CRYPT_CopySimpleChainToElement(chain->context.rgpChain[i],
iElement);
if (!copy->context.rgpChain[i])
ret = FALSE;
}
if (!ret)
{
CRYPT_FreeChainContext(copy);
copy = NULL;
}
else
copy->context.cChain = iChain + 1;
}
else
{
CryptMemFree(copy);
copy = NULL;
}
}
return copy;
}
static PCertificateChain CRYPT_BuildAlternateContextFromChain(
HCERTCHAINENGINE hChainEngine, LPFILETIME pTime, HCERTSTORE hAdditionalStore,
PCertificateChain chain)
{
PCertificateChainEngine engine = (PCertificateChainEngine)hChainEngine;
PCertificateChain alternate;
TRACE("(%p, %p, %p, %p)\n", hChainEngine, pTime, hAdditionalStore, chain);
/* Always start with the last "lower quality" chain to ensure a consistent
* order of alternate creation:
*/
if (chain->context.cLowerQualityChainContext)
chain = (PCertificateChain)chain->context.rgpLowerQualityChainContext[
chain->context.cLowerQualityChainContext - 1];
/* A chain with only one element can't have any alternates */
if (chain->context.cChain <= 1 && chain->context.rgpChain[0]->cElement <= 1)
alternate = NULL;
else
{
DWORD i, j;
PCCERT_CONTEXT alternateIssuer = NULL;
alternate = NULL;
for (i = 0; !alternateIssuer && i < chain->context.cChain; i++)
for (j = 0; !alternateIssuer &&
j < chain->context.rgpChain[i]->cElement - 1; j++)
{
PCCERT_CONTEXT subject =
chain->context.rgpChain[i]->rgpElement[j]->pCertContext;
PCCERT_CONTEXT prevIssuer = CertDuplicateCertificateContext(
chain->context.rgpChain[i]->rgpElement[j + 1]->pCertContext);
alternateIssuer = CRYPT_GetIssuer(prevIssuer->hCertStore,
subject, prevIssuer);
}
if (alternateIssuer)
{
i--;
j--;
alternate = CRYPT_CopyChainToElement(chain, i, j);
if (alternate)
{
BOOL ret = CRYPT_AddCertToSimpleChain(engine,
alternate->context.rgpChain[i], alternateIssuer);
if (ret)
{
ret = CRYPT_BuildSimpleChain(engine, alternate->world,
alternate->context.rgpChain[i]);
if (ret)
CRYPT_CheckSimpleChain(engine,
alternate->context.rgpChain[i], pTime);
CRYPT_CombineTrustStatus(&alternate->context.TrustStatus,
&alternate->context.rgpChain[i]->TrustStatus);
}
if (!ret)
{
CRYPT_FreeChainContext(alternate);
alternate = NULL;
}
}
}
}
TRACE("%p\n", alternate);
return alternate;
}
#define CHAIN_QUALITY_SIGNATURE_VALID 8
#define CHAIN_QUALITY_TIME_VALID 4
#define CHAIN_QUALITY_COMPLETE_CHAIN 2
#define CHAIN_QUALITY_TRUSTED_ROOT 1
#define CHAIN_QUALITY_HIGHEST \
CHAIN_QUALITY_SIGNATURE_VALID | CHAIN_QUALITY_TIME_VALID | \
CHAIN_QUALITY_COMPLETE_CHAIN | CHAIN_QUALITY_TRUSTED_ROOT
#define IS_TRUST_ERROR_SET(TrustStatus, bits) \
(TrustStatus)->dwErrorStatus & (bits)
static DWORD CRYPT_ChainQuality(PCertificateChain chain)
{
DWORD quality = CHAIN_QUALITY_HIGHEST;
if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
CERT_TRUST_IS_UNTRUSTED_ROOT))
quality &= ~CHAIN_QUALITY_TRUSTED_ROOT;
if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
CERT_TRUST_IS_PARTIAL_CHAIN))
if (chain->context.TrustStatus.dwErrorStatus & CERT_TRUST_IS_PARTIAL_CHAIN)
quality &= ~CHAIN_QUALITY_COMPLETE_CHAIN;
if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
CERT_TRUST_IS_NOT_TIME_VALID | CERT_TRUST_IS_NOT_TIME_NESTED))
quality &= ~CHAIN_QUALITY_TIME_VALID;
if (IS_TRUST_ERROR_SET(&chain->context.TrustStatus,
CERT_TRUST_IS_NOT_SIGNATURE_VALID))
quality &= ~CHAIN_QUALITY_SIGNATURE_VALID;
return quality;
}
/* Chooses the highest quality chain among chain and its "lower quality"
* alternate chains. Returns the highest quality chain, with all other
* chains as lower quality chains of it.
*/
static PCertificateChain CRYPT_ChooseHighestQualityChain(
PCertificateChain chain)
{
DWORD i;
/* There are always only two chains being considered: chain, and an
* alternate at chain->rgpLowerQualityChainContext[i]. If the alternate
* has a higher quality than chain, the alternate gets assigned the lower
* quality contexts, with chain taking the alternate's place among the
* lower quality contexts.
*/
for (i = 0; i < chain->context.cLowerQualityChainContext; i++)
{
PCertificateChain alternate =
(PCertificateChain)chain->context.rgpLowerQualityChainContext[i];
if (CRYPT_ChainQuality(alternate) > CRYPT_ChainQuality(chain))
{
alternate->context.cLowerQualityChainContext =
chain->context.cLowerQualityChainContext;
alternate->context.rgpLowerQualityChainContext =
chain->context.rgpLowerQualityChainContext;
alternate->context.rgpLowerQualityChainContext[i] =
(PCCERT_CHAIN_CONTEXT)chain;
chain = alternate;
}
}
return chain;
}
static BOOL CRYPT_AddAlternateChainToChain(PCertificateChain chain,
PCertificateChain alternate)
{
BOOL ret;
if (chain->context.cLowerQualityChainContext)
chain->context.rgpLowerQualityChainContext =
CryptMemRealloc(chain->context.rgpLowerQualityChainContext,
(chain->context.cLowerQualityChainContext + 1) *
sizeof(PCCERT_CHAIN_CONTEXT));
else
chain->context.rgpLowerQualityChainContext =
CryptMemAlloc(sizeof(PCCERT_CHAIN_CONTEXT));
if (chain->context.rgpLowerQualityChainContext)
{
chain->context.rgpLowerQualityChainContext[
chain->context.cLowerQualityChainContext++] =
(PCCERT_CHAIN_CONTEXT)alternate;
ret = TRUE;
}
else
ret = FALSE;
return ret;
}
typedef struct _CERT_CHAIN_PARA_NO_EXTRA_FIELDS {
DWORD cbSize;
CERT_USAGE_MATCH RequestedUsage;
} CERT_CHAIN_PARA_NO_EXTRA_FIELDS, *PCERT_CHAIN_PARA_NO_EXTRA_FIELDS;
typedef struct _CERT_CHAIN_PARA_EXTRA_FIELDS {
DWORD cbSize;
CERT_USAGE_MATCH RequestedUsage;
CERT_USAGE_MATCH RequestedIssuancePolicy;
DWORD dwUrlRetrievalTimeout;
BOOL fCheckRevocationFreshnessTime;
DWORD dwRevocationFreshnessTime;
} CERT_CHAIN_PARA_EXTRA_FIELDS, *PCERT_CHAIN_PARA_EXTRA_FIELDS;
BOOL WINAPI CertGetCertificateChain(HCERTCHAINENGINE hChainEngine,
PCCERT_CONTEXT pCertContext, LPFILETIME pTime, HCERTSTORE hAdditionalStore,
PCERT_CHAIN_PARA pChainPara, DWORD dwFlags, LPVOID pvReserved,
PCCERT_CHAIN_CONTEXT* ppChainContext)
{
BOOL ret;
PCertificateChain chain = NULL;
TRACE("(%p, %p, %p, %p, %p, %08x, %p, %p)\n", hChainEngine, pCertContext,
pTime, hAdditionalStore, pChainPara, dwFlags, pvReserved, ppChainContext);
if (ppChainContext)
*ppChainContext = NULL;
if (!pChainPara)
{
SetLastError(E_INVALIDARG);
return FALSE;
}
if (!pCertContext->pCertInfo->SignatureAlgorithm.pszObjId)
{
SetLastError(ERROR_INVALID_DATA);
return FALSE;
}
if (!hChainEngine)
hChainEngine = CRYPT_GetDefaultChainEngine();
/* FIXME: what about HCCE_LOCAL_MACHINE? */
/* FIXME: pChainPara is for now ignored */
ret = CRYPT_BuildCandidateChainFromCert(hChainEngine, pCertContext, pTime,
hAdditionalStore, &chain);
if (ret)
{
PCertificateChain alternate = NULL;
do {
alternate = CRYPT_BuildAlternateContextFromChain(hChainEngine,
pTime, hAdditionalStore, chain);
/* Alternate contexts are added as "lower quality" contexts of
* chain, to avoid loops in alternate chain creation.
* The highest-quality chain is chosen at the end.
*/
if (alternate)
ret = CRYPT_AddAlternateChainToChain(chain, alternate);
} while (ret && alternate);
chain = CRYPT_ChooseHighestQualityChain(chain);
if (!(dwFlags & CERT_CHAIN_RETURN_LOWER_QUALITY_CONTEXTS))
{
CRYPT_FreeLowerQualityChains(chain);
chain->context.cLowerQualityChainContext = 0;
chain->context.rgpLowerQualityChainContext = NULL;
}
if (ppChainContext)
*ppChainContext = (PCCERT_CHAIN_CONTEXT)chain;
else
CertFreeCertificateChain((PCCERT_CHAIN_CONTEXT)chain);
}
TRACE("returning %d\n", ret);
return ret;
}
PCCERT_CHAIN_CONTEXT WINAPI CertDuplicateCertificateChain(
PCCERT_CHAIN_CONTEXT pChainContext)
{
PCertificateChain chain = (PCertificateChain)pChainContext;
TRACE("(%p)\n", pChainContext);
if (chain)
InterlockedIncrement(&chain->ref);
return pChainContext;
}
VOID WINAPI CertFreeCertificateChain(PCCERT_CHAIN_CONTEXT pChainContext)
{
PCertificateChain chain = (PCertificateChain)pChainContext;
TRACE("(%p)\n", pChainContext);
if (chain)
{
if (InterlockedDecrement(&chain->ref) == 0)
CRYPT_FreeChainContext(chain);
}
}
static void find_element_with_error(PCCERT_CHAIN_CONTEXT chain, DWORD error,
LONG *iChain, LONG *iElement)
{
DWORD i, j;
for (i = 0; i < chain->cChain; i++)
for (j = 0; j < chain->rgpChain[i]->cElement; j++)
if (chain->rgpChain[i]->rgpElement[j]->TrustStatus.dwErrorStatus &
error)
{
*iChain = i;
*iElement = j;
return;
}
}
static BOOL WINAPI verify_base_policy(LPCSTR szPolicyOID,
PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
{
pPolicyStatus->lChainIndex = pPolicyStatus->lElementIndex = -1;
if (pChainContext->TrustStatus.dwErrorStatus &
CERT_TRUST_IS_NOT_SIGNATURE_VALID)
{
pPolicyStatus->dwError = TRUST_E_CERT_SIGNATURE;
find_element_with_error(pChainContext,
CERT_TRUST_IS_NOT_SIGNATURE_VALID, &pPolicyStatus->lChainIndex,
&pPolicyStatus->lElementIndex);
}
else if (pChainContext->TrustStatus.dwErrorStatus &
CERT_TRUST_IS_UNTRUSTED_ROOT)
{
pPolicyStatus->dwError = CERT_E_UNTRUSTEDROOT;
find_element_with_error(pChainContext,
CERT_TRUST_IS_UNTRUSTED_ROOT, &pPolicyStatus->lChainIndex,
&pPolicyStatus->lElementIndex);
}
else if (pChainContext->TrustStatus.dwErrorStatus & CERT_TRUST_IS_CYCLIC)
{
pPolicyStatus->dwError = CERT_E_CHAINING;
find_element_with_error(pChainContext, CERT_TRUST_IS_CYCLIC,
&pPolicyStatus->lChainIndex, &pPolicyStatus->lElementIndex);
/* For a cyclic chain, which element is a cycle isn't meaningful */
pPolicyStatus->lElementIndex = -1;
}
return TRUE;
}
static BYTE msTestPubKey1[] = {
0x30,0x47,0x02,0x40,0x81,0x55,0x22,0xb9,0x8a,0xa4,0x6f,0xed,0xd6,0xe7,0xd9,
0x66,0x0f,0x55,0xbc,0xd7,0xcd,0xd5,0xbc,0x4e,0x40,0x02,0x21,0xa2,0xb1,0xf7,
0x87,0x30,0x85,0x5e,0xd2,0xf2,0x44,0xb9,0xdc,0x9b,0x75,0xb6,0xfb,0x46,0x5f,
0x42,0xb6,0x9d,0x23,0x36,0x0b,0xde,0x54,0x0f,0xcd,0xbd,0x1f,0x99,0x2a,0x10,
0x58,0x11,0xcb,0x40,0xcb,0xb5,0xa7,0x41,0x02,0x03,0x01,0x00,0x01 };
static BYTE msTestPubKey2[] = {
0x30,0x48,0x02,0x41,0x00,0x81,0x55,0x22,0xb9,0x8a,0xa4,0x6f,0xed,0xd6,0xe7,
0xd9,0x66,0x0f,0x55,0xbc,0xd7,0xcd,0xd5,0xbc,0x4e,0x40,0x02,0x21,0xa2,0xb1,
0xf7,0x87,0x30,0x85,0x5e,0xd2,0xf2,0x44,0xb9,0xdc,0x9b,0x75,0xb6,0xfb,0x46,
0x5f,0x42,0xb6,0x9d,0x23,0x36,0x0b,0xde,0x54,0x0f,0xcd,0xbd,0x1f,0x99,0x2a,
0x10,0x58,0x11,0xcb,0x40,0xcb,0xb5,0xa7,0x41,0x02,0x03,0x01,0x00,0x01 };
static BYTE msTestPubKey3[] = {
0x30,0x47,0x02,0x40,0x9c,0x50,0x05,0x1d,0xe2,0x0e,0x4c,0x53,0xd8,0xd9,0xb5,
0xe5,0xfd,0xe9,0xe3,0xad,0x83,0x4b,0x80,0x08,0xd9,0xdc,0xe8,0xe8,0x35,0xf8,
0x11,0xf1,0xe9,0x9b,0x03,0x7a,0x65,0x64,0x76,0x35,0xce,0x38,0x2c,0xf2,0xb6,
0x71,0x9e,0x06,0xd9,0xbf,0xbb,0x31,0x69,0xa3,0xf6,0x30,0xa0,0x78,0x7b,0x18,
0xdd,0x50,0x4d,0x79,0x1e,0xeb,0x61,0xc1,0x02,0x03,0x01,0x00,0x01 };
static BOOL WINAPI verify_authenticode_policy(LPCSTR szPolicyOID,
PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
{
BOOL ret = verify_base_policy(szPolicyOID, pChainContext, pPolicyPara,
pPolicyStatus);
if (ret && pPolicyStatus->dwError == CERT_E_UNTRUSTEDROOT)
{
CERT_PUBLIC_KEY_INFO msPubKey = { { 0 } };
BOOL isMSTestRoot = FALSE;
PCCERT_CONTEXT failingCert =
pChainContext->rgpChain[pPolicyStatus->lChainIndex]->
rgpElement[pPolicyStatus->lElementIndex]->pCertContext;
DWORD i;
CRYPT_DATA_BLOB keyBlobs[] = {
{ sizeof(msTestPubKey1), msTestPubKey1 },
{ sizeof(msTestPubKey2), msTestPubKey2 },
{ sizeof(msTestPubKey3), msTestPubKey3 },
};
/* Check whether the root is an MS test root */
for (i = 0; !isMSTestRoot && i < sizeof(keyBlobs) / sizeof(keyBlobs[0]);
i++)
{
msPubKey.PublicKey.cbData = keyBlobs[i].cbData;
msPubKey.PublicKey.pbData = keyBlobs[i].pbData;
if (CertComparePublicKeyInfo(
X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
&failingCert->pCertInfo->SubjectPublicKeyInfo, &msPubKey))
isMSTestRoot = TRUE;
}
if (isMSTestRoot)
pPolicyStatus->dwError = CERT_E_UNTRUSTEDTESTROOT;
}
return ret;
}
static BOOL WINAPI verify_basic_constraints_policy(LPCSTR szPolicyOID,
PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
{
pPolicyStatus->lChainIndex = pPolicyStatus->lElementIndex = -1;
if (pChainContext->TrustStatus.dwErrorStatus &
CERT_TRUST_INVALID_BASIC_CONSTRAINTS)
{
pPolicyStatus->dwError = TRUST_E_BASIC_CONSTRAINTS;
find_element_with_error(pChainContext,
CERT_TRUST_INVALID_BASIC_CONSTRAINTS, &pPolicyStatus->lChainIndex,
&pPolicyStatus->lElementIndex);
}
return TRUE;
}
typedef BOOL (WINAPI *CertVerifyCertificateChainPolicyFunc)(LPCSTR szPolicyOID,
PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
PCERT_CHAIN_POLICY_STATUS pPolicyStatus);
BOOL WINAPI CertVerifyCertificateChainPolicy(LPCSTR szPolicyOID,
PCCERT_CHAIN_CONTEXT pChainContext, PCERT_CHAIN_POLICY_PARA pPolicyPara,
PCERT_CHAIN_POLICY_STATUS pPolicyStatus)
{
static HCRYPTOIDFUNCSET set = NULL;
BOOL ret = FALSE;
CertVerifyCertificateChainPolicyFunc verifyPolicy = NULL;
HCRYPTOIDFUNCADDR hFunc = NULL;
TRACE("(%s, %p, %p, %p)\n", debugstr_a(szPolicyOID), pChainContext,
pPolicyPara, pPolicyStatus);
if (!HIWORD(szPolicyOID))
{
switch (LOWORD(szPolicyOID))
{
case (int)CERT_CHAIN_POLICY_BASE:
verifyPolicy = verify_base_policy;
break;
case (int)CERT_CHAIN_POLICY_AUTHENTICODE:
verifyPolicy = verify_authenticode_policy;
break;
case (int)CERT_CHAIN_POLICY_BASIC_CONSTRAINTS:
verifyPolicy = verify_basic_constraints_policy;
break;
default:
FIXME("unimplemented for %d\n", LOWORD(szPolicyOID));
}
}
if (!verifyPolicy)
{
if (!set)
set = CryptInitOIDFunctionSet(
CRYPT_OID_VERIFY_CERTIFICATE_CHAIN_POLICY_FUNC, 0);
CryptGetOIDFunctionAddress(set, X509_ASN_ENCODING, szPolicyOID, 0,
(void **)&verifyPolicy, hFunc);
}
if (verifyPolicy)
ret = verifyPolicy(szPolicyOID, pChainContext, pPolicyPara,
pPolicyStatus);
if (hFunc)
CryptFreeOIDFunctionAddress(hFunc, 0);
return ret;
}