RTDECL(int) RTAsn1DynType_Compare(PCRTASN1DYNTYPE pLeft, PCRTASN1DYNTYPE pRight)
{
if (RTAsn1DynType_IsPresent(pLeft) && RTAsn1DynType_IsPresent(pRight))
{
if (pLeft->enmType != pRight->enmType)
return pLeft->enmType < pRight->enmType ? -1 : 1;
switch (pLeft->enmType)
{
case RTASN1TYPE_CORE: return RTAsn1Core_Compare(&pLeft->u.Core, &pRight->u.Core); break;
case RTASN1TYPE_NULL: return RTAsn1Null_Compare(&pLeft->u.Asn1Null, &pRight->u.Asn1Null);
case RTASN1TYPE_INTEGER: return RTAsn1Integer_Compare(&pLeft->u.Integer, &pRight->u.Integer);
case RTASN1TYPE_BOOLEAN: return RTAsn1Boolean_Compare(&pLeft->u.Boolean, &pRight->u.Boolean);
case RTASN1TYPE_STRING: return RTAsn1String_Compare(&pLeft->u.String, &pRight->u.String);
case RTASN1TYPE_OCTET_STRING: return RTAsn1OctetString_Compare(&pLeft->u.OctetString, &pRight->u.OctetString);
case RTASN1TYPE_BIT_STRING: return RTAsn1BitString_Compare(&pLeft->u.BitString, &pRight->u.BitString);
case RTASN1TYPE_TIME: return RTAsn1Time_Compare(&pLeft->u.Time, &pRight->u.Time);
case RTASN1TYPE_OBJID: return RTAsn1ObjId_Compare(&pLeft->u.ObjId, &pRight->u.ObjId);
default: AssertFailedReturn(-1);
}
}
else
return (int)RTAsn1DynType_IsPresent(pLeft) - (int)RTAsn1DynType_IsPresent(pRight);
}
/**
* Deals with authenticated attributes.
*
* When authenticated attributes are present (checked by caller) we must:
* - fish out the content type and check it against the content inof,
* - fish out the message digest among and check it against *phDigest,
* - compute the message digest of the authenticated attributes and
* replace *phDigest with this for the signature verification.
*
* @returns IPRT status code.
* @param pSignerInfo The signer info being verified.
* @param pSignedData The signed data.
* @param phDigest On input this is the digest of the content. On
* output it will (on success) be a reference to
* the message digest of the authenticated
* attributes. The input reference is consumed.
* The caller shall release the output reference.
* @param fFlags Flags.
* @param pErrInfo Extended error info, optional.
*/
static int rtCrPkcs7VerifySignerInfoAuthAttribs(PCRTCRPKCS7SIGNERINFO pSignerInfo, PCRTCRPKCS7SIGNEDDATA pSignedData,
PRTCRDIGEST phDigest, uint32_t fFlags, PRTERRINFO pErrInfo)
{
/*
* Scan the attributes and validate the two required attributes
* (RFC-2315, chapter 9.2, fourth bullet). Checking that we've got exactly
* one of each of them is checked by the santiy checker function, so we'll
* just assert that it did it's job here.
*/
uint32_t cContentTypes = 0;
uint32_t cMessageDigests = 0;
uint32_t i = pSignerInfo->AuthenticatedAttributes.cItems;
while (i-- > 0)
{
PCRTCRPKCS7ATTRIBUTE pAttrib = &pSignerInfo->AuthenticatedAttributes.paItems[i];
if (RTAsn1ObjId_CompareWithString(&pAttrib->Type, RTCR_PKCS9_ID_CONTENT_TYPE_OID) == 0)
{
AssertReturn(!cContentTypes, VERR_CR_PKCS7_INTERNAL_ERROR);
AssertReturn(pAttrib->enmType == RTCRPKCS7ATTRIBUTETYPE_OBJ_IDS, VERR_CR_PKCS7_INTERNAL_ERROR);
AssertReturn(pAttrib->uValues.pObjIds->cItems == 1, VERR_CR_PKCS7_INTERNAL_ERROR);
if ( !(fFlags & RTCRPKCS7VERIFY_SD_F_COUNTER_SIGNATURE) /* See note about microsoft below. */
&& RTAsn1ObjId_Compare(&pAttrib->uValues.pObjIds->paItems[0], &pSignedData->ContentInfo.ContentType) != 0)
return RTErrInfoSetF(pErrInfo, VERR_CR_PKCS7_CONTENT_TYPE_ATTRIB_MISMATCH,
"Expected content-type %s, found %s",
&pAttrib->uValues.pObjIds->paItems[0], pSignedData->ContentInfo.ContentType.szObjId);
cContentTypes++;
}
else if (RTAsn1ObjId_CompareWithString(&pAttrib->Type, RTCR_PKCS9_ID_MESSAGE_DIGEST_OID) == 0)
{
AssertReturn(!cMessageDigests, VERR_CR_PKCS7_INTERNAL_ERROR);
AssertReturn(pAttrib->enmType == RTCRPKCS7ATTRIBUTETYPE_OCTET_STRINGS, VERR_CR_PKCS7_INTERNAL_ERROR);
AssertReturn(pAttrib->uValues.pOctetStrings->cItems == 1, VERR_CR_PKCS7_INTERNAL_ERROR);
if (!RTCrDigestMatch(*phDigest,
pAttrib->uValues.pOctetStrings->paItems[0].Asn1Core.uData.pv,
pAttrib->uValues.pOctetStrings->paItems[0].Asn1Core.cb))
{
size_t cbHash = RTCrDigestGetHashSize(*phDigest);
if (cbHash != pAttrib->uValues.pOctetStrings->paItems[0].Asn1Core.cb)
return RTErrInfoSetF(pErrInfo, VERR_CR_PKCS7_MESSAGE_DIGEST_ATTRIB_MISMATCH,
"Authenticated message-digest attribute mismatch: cbHash=%#zx cbValue=%#x",
cbHash, pAttrib->uValues.pOctetStrings->paItems[0].Asn1Core.cb);
return RTErrInfoSetF(pErrInfo, VERR_CR_PKCS7_MESSAGE_DIGEST_ATTRIB_MISMATCH,
"Authenticated message-digest attribute mismatch (cbHash=%#zx):\n"
"signed: %.*Rhxs\n"
"our: %.*Rhxs\n",
cbHash,
cbHash, pAttrib->uValues.pOctetStrings->paItems[0].Asn1Core.uData.pv,
cbHash, RTCrDigestGetHash(*phDigest));
}
cMessageDigests++;
}
}
/*
* Full error reporting here as we don't currently extensively santiy check
* counter signatures.
* Note! Microsoft includes content info in their timestamp counter signatures,
* at least for vista, despite the RFC-3852 stating counter signatures
* "MUST NOT contain a content-type".
*/
if (RT_UNLIKELY( cContentTypes != 1
&& !(fFlags & RTCRPKCS7VERIFY_SD_F_COUNTER_SIGNATURE)))
return RTErrInfoSet(pErrInfo, VERR_CR_PKCS7_MISSING_CONTENT_TYPE_ATTRIB,
"Missing authenticated content-type attribute.");
if (RT_UNLIKELY(cMessageDigests != 1))
return RTErrInfoSet(pErrInfo, VERR_CR_PKCS7_MISSING_MESSAGE_DIGEST_ATTRIB,
"Missing authenticated message-digest attribute.");
/*
* Calculate the digest of the the authenticated attributes for use in the
* signature validation.
*/
if ( pSignerInfo->DigestAlgorithm.Parameters.enmType != RTASN1TYPE_NULL
&& pSignerInfo->DigestAlgorithm.Parameters.enmType != RTASN1TYPE_NOT_PRESENT)
return RTErrInfoSet(pErrInfo, VERR_CR_PKCS7_DIGEST_PARAMS_NOT_IMPL, "Digest algorithm has unsupported parameters");
RTCRDIGEST hDigest;
int rc = RTCrDigestCreateByObjId(&hDigest, &pSignerInfo->DigestAlgorithm.Algorithm);
if (RT_SUCCESS(rc))
{
RTCrDigestRelease(*phDigest);
*phDigest = hDigest;
/* ASSUMES that the attributes are encoded according to DER. */
uint8_t const *pbData = (uint8_t const *)RTASN1CORE_GET_RAW_ASN1_PTR(&pSignerInfo->AuthenticatedAttributes.SetCore.Asn1Core);
uint32_t cbData = RTASN1CORE_GET_RAW_ASN1_SIZE(&pSignerInfo->AuthenticatedAttributes.SetCore.Asn1Core);
uint8_t bSetOfTag = ASN1_TAG_SET | ASN1_TAGCLASS_UNIVERSAL | ASN1_TAGFLAG_CONSTRUCTED;
rc = RTCrDigestUpdate(hDigest, &bSetOfTag, sizeof(bSetOfTag)); /* Replace the implict tag with a SET-OF tag. */
if (RT_SUCCESS(rc))
rc = RTCrDigestUpdate(hDigest, pbData + sizeof(bSetOfTag), cbData - sizeof(bSetOfTag)); /* Skip the implicit tag. */
if (RT_SUCCESS(rc))
rc = RTCrDigestFinal(hDigest, NULL, 0);
}
return rc;
}
