/** @file
RFC3161 Timestamp Countersignature Verification over OpenSSL.
The timestamp is generated by a TimeStamping Authority (TSA) and asserts that a
publisher's signature existed before the specified time. The timestamp extends
the lifetime of the signature when a signing certificate expires or is later
revoked.
Copyright (c) 2014 - 2015, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "InternalCryptLib.h"
#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include <openssl/pkcs7.h>
//
// OID ASN.1 Value for SPC_RFC3161_OBJID ("1.3.6.1.4.1.311.3.3.1")
//
UINT8 mSpcRFC3161OidValue[] = {
0x2b, 0x06, 0x01, 0x04, 0x01, 0x82, 0x37, 0x03, 0x03, 0x01
};
///
/// The messageImprint field SHOULD contain the hash of the datum to be
/// time-stamped. The hash is represented as an OCTET STRING. Its
/// length MUST match the length of the hash value for that algorithm
/// (e.g., 20 bytes for SHA-1 or 16 bytes for MD5).
///
/// MessageImprint ::= SEQUENCE {
/// hashAlgorithm AlgorithmIdentifier,
/// hashedMessage OCTET STRING }
///
typedef struct {
X509_ALGOR *HashAlgorithm;
ASN1_OCTET_STRING *HashedMessage;
} TS_MESSAGE_IMPRINT;
//
// ASN.1 Functions for TS_MESSAGE_IMPRINT
//
DECLARE_ASN1_FUNCTIONS (TS_MESSAGE_IMPRINT)
ASN1_SEQUENCE (TS_MESSAGE_IMPRINT) = {
ASN1_SIMPLE (TS_MESSAGE_IMPRINT, HashAlgorithm, X509_ALGOR),
ASN1_SIMPLE (TS_MESSAGE_IMPRINT, HashedMessage, ASN1_OCTET_STRING)
} ASN1_SEQUENCE_END (TS_MESSAGE_IMPRINT)
IMPLEMENT_ASN1_FUNCTIONS (TS_MESSAGE_IMPRINT)
///
/// Accuracy represents the time deviation around the UTC time contained
/// in GeneralizedTime of time-stamp token.
///
/// Accuracy ::= SEQUENCE {
/// seconds INTEGER OPTIONAL,
/// millis [0] INTEGER (1..999) OPTIONAL,
/// micros [1] INTEGER (1..999) OPTIONAL }
///
typedef struct {
ASN1_INTEGER *Seconds;
ASN1_INTEGER *Millis;
ASN1_INTEGER *Micros;
} TS_ACCURACY;
//
// ASN.1 Functions for TS_ACCURACY
//
DECLARE_ASN1_FUNCTIONS (TS_ACCURACY)
ASN1_SEQUENCE (TS_ACCURACY) = {
ASN1_OPT (TS_ACCURACY, Seconds, ASN1_INTEGER),
ASN1_IMP_OPT (TS_ACCURACY, Millis, ASN1_INTEGER, 0),
ASN1_IMP_OPT (TS_ACCURACY, Micros, ASN1_INTEGER, 1)
} ASN1_SEQUENCE_END (TS_ACCURACY)
IMPLEMENT_ASN1_FUNCTIONS (TS_ACCURACY)
///
/// The timestamp token info resulting from a successful timestamp request,
/// as defined in RFC 3161.
///
/// TSTInfo ::= SEQUENCE {
/// version INTEGER { v1(1) },
/// policy TSAPolicyId,
/// messageImprint MessageImprint,
/// -- MUST have the same value as the similar field in
/// -- TimeStampReq
/// serialNumber INTEGER,
/// -- Time-Stamping users MUST be ready to accommodate integers
/// -- up to 160 bits.
/// genTime GeneralizedTime,
/// accuracy Accuracy OPTIONAL,
/// ordering BOOLEAN DEFAULT FALSE,
/// nonce INTEGER OPTIONAL,
/// -- MUST be present if the similar field was present
/// -- in TimeStampReq. In that case it MUST have the same value.
/// tsa [0] GeneralName OPTIONAL,
/// extensions [1] IMPLICIT Extensions OPTIONAL }
///
typedef struct {
ASN1_INTEGER *Version;
ASN1_OBJECT *Policy;
TS_MESSAGE_IMPRINT *MessageImprint;
ASN1_INTEGER *SerialNumber;
ASN1_GENERALIZEDTIME *GenTime;
TS_ACCURACY *Accuracy;
ASN1_BOOLEAN Ordering;
ASN1_INTEGER *Nonce;
GENERAL_NAME *Tsa;
STACK_OF(X509_EXTENSION) *Extensions;
} TS_TST_INFO;
//
// ASN.1 Functions for TS_TST_INFO
//
DECLARE_ASN1_FUNCTIONS (TS_TST_INFO)
ASN1_SEQUENCE (TS_TST_INFO) = {
ASN1_SIMPLE (TS_TST_INFO, Version, ASN1_INTEGER),
ASN1_SIMPLE (TS_TST_INFO, Policy, ASN1_OBJECT),
ASN1_SIMPLE (TS_TST_INFO, MessageImprint, TS_MESSAGE_IMPRINT),
ASN1_SIMPLE (TS_TST_INFO, SerialNumber, ASN1_INTEGER),
ASN1_SIMPLE (TS_TST_INFO, GenTime, ASN1_GENERALIZEDTIME),
ASN1_OPT (TS_TST_INFO, Accuracy, TS_ACCURACY),
ASN1_OPT (TS_TST_INFO, Ordering, ASN1_FBOOLEAN),
ASN1_OPT (TS_TST_INFO, Nonce, ASN1_INTEGER),
ASN1_EXP_OPT(TS_TST_INFO, Tsa, GENERAL_NAME, 0),
ASN1_IMP_SEQUENCE_OF_OPT (TS_TST_INFO, Extensions, X509_EXTENSION, 1)
} ASN1_SEQUENCE_END (TS_TST_INFO)
IMPLEMENT_ASN1_FUNCTIONS (TS_TST_INFO)
/**
Convert ASN.1 GeneralizedTime to EFI Time.
@param[in] Asn1Time Pointer to the ASN.1 GeneralizedTime to be converted.
@param[out] SigningTime Return the corresponding EFI Time.
@retval TRUE The time convertion succeeds.
@retval FALSE Invalid parameters.
**/
BOOLEAN
EFIAPI
ConvertAsn1TimeToEfiTime (
IN ASN1_TIME *Asn1Time,
OUT EFI_TIME *EfiTime
)
{
CONST CHAR8 *Str;
UINTN Index;
if ((Asn1Time == NULL) || (EfiTime == NULL)) {
return FALSE;
}
Str = (CONST CHAR8*)Asn1Time->data;
SetMem (EfiTime, 0, sizeof (EFI_TIME));
Index = 0;
if (Asn1Time->type == V_ASN1_UTCTIME) { /* two digit year */
EfiTime->Year = (Str[Index++] - '0') * 10;
EfiTime->Year += (Str[Index++] - '0');
if (EfiTime->Year < 70) {
EfiTime->Year += 100;
}
} else if (Asn1Time->type == V_ASN1_GENERALIZEDTIME) { /* four digit year */
EfiTime->Year = (Str[Index++] - '0') * 1000;
EfiTime->Year += (Str[Index++] - '0') * 100;
EfiTime->Year += (Str[Index++] - '0') * 10;
EfiTime->Year += (Str[Index++] - '0');
if ((EfiTime->Year < 1900) || (EfiTime->Year > 9999)) {
return FALSE;
}
}
EfiTime->Month = (Str[Index++] - '0') * 10;
EfiTime->Month += (Str[Index++] - '0');
if ((EfiTime->Month < 1) || (EfiTime->Month > 12)) {
return FALSE;
}
EfiTime->Day = (Str[Index++] - '0') * 10;
EfiTime->Day += (Str[Index++] - '0');
if ((EfiTime->Day < 1) || (EfiTime->Day > 31)) {
return FALSE;
}
EfiTime->Hour = (Str[Index++] - '0') * 10;
EfiTime->Hour += (Str[Index++] - '0');
if (EfiTime->Hour > 23) {
return FALSE;
}
EfiTime->Minute = (Str[Index++] - '0') * 10;
EfiTime->Minute += (Str[Index++] - '0');
if (EfiTime->Minute > 59) {
return FALSE;
}
EfiTime->Second = (Str[Index++] - '0') * 10;
EfiTime->Second += (Str[Index++] - '0');
if (EfiTime->Second > 59) {
return FALSE;
}
/* Note: we did not adjust the time based on time zone information */
return TRUE;
}
/**
Check the validity of TimeStamp Token Information.
@param[in] TstInfo Pointer to the TS_TST_INFO structure.
@param[in] TimestampedData Pointer to the data to be time-stamped.
@param[in] DataSize Size of timestamped data in bytes.
@retval TRUE The TimeStamp Token Information is valid.
@retval FALSE Invalid TimeStamp Token Information.
**/
BOOLEAN
EFIAPI
CheckTSTInfo (
IN CONST TS_TST_INFO *TstInfo,
IN CONST UINT8 *TimestampedData,
IN UINTN DataSize
)
{
BOOLEAN Status;
TS_MESSAGE_IMPRINT *Imprint;
X509_ALGOR *HashAlgo;
CONST EVP_MD *Md;
EVP_MD_CTX MdCtx;
UINTN MdSize;
UINT8 *HashedMsg;
//
// Initialization
//
Status = FALSE;
HashAlgo = NULL;
HashedMsg = NULL;
//
// -- Check version number of Timestamp:
// The version field (currently v1) describes the version of the time-stamp token.
// Conforming time-stamping servers MUST be able to provide version 1 time-stamp tokens.
//
if ((ASN1_INTEGER_get (TstInfo->Version)) != 1) {
return FALSE;
}
//
// -- Check Policies
// The policy field MUST indicate the TSA's policy under which the response was produced.
//
if (TstInfo->Policy == NULL) {
/// NOTE: Need to check if the requested and returned policies.
/// We have no information about the Requested TSA Policy.
return FALSE;
}
//
// -- Compute & Check Message Imprint
//
Imprint = TstInfo->MessageImprint;
HashAlgo = X509_ALGOR_dup (Imprint->HashAlgorithm);
Md = EVP_get_digestbyobj (HashAlgo->algorithm);
if (Md == NULL) {
goto _Exit;
}
MdSize = EVP_MD_size (Md);
HashedMsg = AllocateZeroPool (MdSize);
if (HashedMsg == NULL) {
goto _Exit;
}
EVP_DigestInit (&MdCtx, Md);
EVP_DigestUpdate (&MdCtx, TimestampedData, DataSize);
EVP_DigestFinal (&MdCtx, HashedMsg, NULL);
if ((MdSize == (UINTN)ASN1_STRING_length (Imprint->HashedMessage)) &&
(CompareMem (HashedMsg, ASN1_STRING_data (Imprint->HashedMessage), MdSize) != 0)) {
goto _Exit;
}
//
// -- Check Nonces
//
if (TstInfo->Nonce != NULL) {
//
// Nonces is optional, No error if no nonce is returned;
//
}
//
// -- Check if the TSA name and signer certificate is matched.
//
if (TstInfo->Tsa != NULL) {
//
// Ignored the optional Tsa field checking.
//
}
Status = TRUE;
_Exit:
X509_ALGOR_free (HashAlgo);
if (HashedMsg != NULL) {
FreePool (HashedMsg);
}
return Status;
}
/**
Verifies the validility of a TimeStamp Token as described in RFC 3161 ("Internet
X.509 Public Key Infrastructure Time-Stamp Protocol (TSP)").
If TSToken is NULL, then return FALSE.
If TimestampedData is NULL, then return FALSE.
@param[in] TSToken Pointer to the RFC3161 TimeStamp Token, which is generated
by a TSA and located in the software publisher's SignerInfo
structure.
@param[in] TokenSize Size of the TimeStamp Token in bytes.
@param[in] TsaCert Pointer to a trusted/root TSA certificate encoded in DER.
@param[in] CertSize Size of the trusted TSA certificate in bytes.
@param[in] TimestampedData Pointer to the data to be time-stamped.
@param[in] DataSize Size of timestamped data in bytes.
@param[out] SigningTime Return the time of timestamp generation time if the timestamp
signature is valid.
@retval TRUE The specified timestamp token is valid.
@retval FALSE Invalid timestamp token.
**/
BOOLEAN
EFIAPI
TimestampTokenVerify (
IN CONST UINT8 *TSToken,
IN UINTN TokenSize,
IN CONST UINT8 *TsaCert,
IN UINTN CertSize,
IN CONST UINT8 *TimestampedData,
IN UINTN DataSize,
OUT EFI_TIME *SigningTime
)
{
BOOLEAN Status;
CONST UINT8 *TokenTemp;
PKCS7 *Pkcs7;
X509 *Cert;
CONST UINT8 *CertTemp;
X509_STORE *CertStore;
BIO *OutBio;
UINT8 *TstData;
UINTN TstSize;
CONST UINT8 *TstTemp;
TS_TST_INFO *TstInfo;
Status = FALSE;
//
// Check input parameters
//
if ((TSToken == NULL) || (TsaCert == NULL) || (TimestampedData == NULL) ||
(TokenSize > INT_MAX) || (CertSize > INT_MAX) || (DataSize > INT_MAX)) {
return FALSE;
}
//
// Initializations
//
if (SigningTime != NULL) {
SetMem (SigningTime, sizeof (EFI_TIME), 0);
}
Pkcs7 = NULL;
Cert = NULL;
CertStore = NULL;
OutBio = NULL;
TstData = NULL;
TstInfo = NULL;
//
// TimeStamp Token should contain one valid DER-encoded ASN.1 PKCS#7 structure.
//
TokenTemp = TSToken;
Pkcs7 = d2i_PKCS7 (NULL, (const unsigned char **) &TokenTemp, (int) TokenSize);
if (Pkcs7 == NULL) {
goto _Exit;
}
//
// The timestamp signature (TSA's response) will be one PKCS#7 signed data.
//
if (!PKCS7_type_is_signed (Pkcs7)) {
goto _Exit;
}
//
// Read the trusted TSA certificate (DER-encoded), and Construct X509 Certificate.
//
CertTemp = TsaCert;
Cert = d2i_X509 (NULL, &CertTemp, (long) CertSize);
if (Cert == NULL) {
goto _Exit;
}
//
// Setup X509 Store for trusted certificate.
//
CertStore = X509_STORE_new ();
if ((CertStore == NULL) || !(X509_STORE_add_cert (CertStore, Cert))) {
goto _Exit;
}
//
// Allow partial certificate chains, terminated by a non-self-signed but
// still trusted intermediate certificate. Also disable time checks.
//
X509_STORE_set_flags (CertStore,
X509_V_FLAG_PARTIAL_CHAIN | X509_V_FLAG_NO_CHECK_TIME);
X509_STORE_set_purpose (CertStore, X509_PURPOSE_ANY);
//
// Verifies the PKCS#7 signedData structure, and output the signed contents.
//
OutBio = BIO_new (BIO_s_mem ());
if (OutBio == NULL) {
goto _Exit;
}
if (!PKCS7_verify (Pkcs7, NULL, CertStore, NULL, OutBio, PKCS7_BINARY)) {
goto _Exit;
}
//
// Read the signed contents detached in timestamp signature.
//
TstData = AllocateZeroPool (2048);
if (TstData == NULL) {
goto _Exit;
}
TstSize = BIO_read (OutBio, (void *) TstData, 2048);
//
// Construct TS_TST_INFO structure from the signed contents.
//
TstTemp = TstData;
TstInfo = d2i_TS_TST_INFO (NULL, (const unsigned char **) &TstTemp,
(int)TstSize);
if (TstInfo == NULL) {
goto _Exit;
}
//
// Check TS_TST_INFO structure.
//
Status = CheckTSTInfo (TstInfo, TimestampedData, DataSize);
if (!Status) {
goto _Exit;
}
//
// Retrieve the signing time from TS_TST_INFO structure.
//
if (SigningTime != NULL) {
SetMem (SigningTime, sizeof (EFI_TIME), 0);
Status = ConvertAsn1TimeToEfiTime (TstInfo->GenTime, SigningTime);
}
_Exit:
//
// Release Resources
//
PKCS7_free (Pkcs7);
X509_free (Cert);
X509_STORE_free (CertStore);
BIO_free (OutBio);
TS_TST_INFO_free (TstInfo);
if (TstData != NULL) {
FreePool (TstData);
}
return Status;
}
/**
Verifies the validility of a RFC3161 Timestamp CounterSignature embedded in PE/COFF Authenticode
signature.
If AuthData is NULL, then return FALSE.
@param[in] AuthData Pointer to the Authenticode Signature retrieved from signed
PE/COFF image to be verified.
@param[in] DataSize Size of the Authenticode Signature in bytes.
@param[in] TsaCert Pointer to a trusted/root TSA certificate encoded in DER, which
is used for TSA certificate chain verification.
@param[in] CertSize Size of the trusted certificate in bytes.
@param[out] SigningTime Return the time of timestamp generation time if the timestamp
signature is valid.
@retval TRUE The specified Authenticode includes a valid RFC3161 Timestamp CounterSignature.
@retval FALSE No valid RFC3161 Timestamp CounterSignature in the specified Authenticode data.
**/
BOOLEAN
EFIAPI
ImageTimestampVerify (
IN CONST UINT8 *AuthData,
IN UINTN DataSize,
IN CONST UINT8 *TsaCert,
IN UINTN CertSize,
OUT EFI_TIME *SigningTime
)
{
BOOLEAN Status;
PKCS7 *Pkcs7;
CONST UINT8 *Temp;
STACK_OF(PKCS7_SIGNER_INFO) *SignerInfos;
PKCS7_SIGNER_INFO *SignInfo;
UINTN Index;
STACK_OF(X509_ATTRIBUTE) *Sk;
X509_ATTRIBUTE *Xa;
ASN1_OBJECT *XaObj;
ASN1_TYPE *Asn1Type;
ASN1_OCTET_STRING *EncDigest;
UINT8 *TSToken;
UINTN TokenSize;
//
// Input Parameters Checking.
//
if ((AuthData == NULL) || (TsaCert == NULL)) {
return FALSE;
}
if ((DataSize > INT_MAX) || (CertSize > INT_MAX)) {
return FALSE;
}
//
// Register & Initialize necessary digest algorithms for PKCS#7 Handling.
//
if ((EVP_add_digest (EVP_md5 ()) == 0) || (EVP_add_digest (EVP_sha1 ()) == 0) ||
(EVP_add_digest (EVP_sha256 ()) == 0) || (EVP_add_digest_alias (SN_sha1WithRSAEncryption, SN_sha1WithRSA)) == 0) {
return FALSE;
}
//
// Initialization.
//
Status = FALSE;
Pkcs7 = NULL;
SignInfo = NULL;
//
// Decode ASN.1-encoded Authenticode data into PKCS7 structure.
//
Temp = AuthData;
Pkcs7 = d2i_PKCS7 (NULL, (const unsigned char **) &Temp, (int) DataSize);
if (Pkcs7 == NULL) {
goto _Exit;
}
//
// Check if there is one and only one signer.
//
SignerInfos = PKCS7_get_signer_info (Pkcs7);
if (!SignerInfos || (sk_PKCS7_SIGNER_INFO_num (SignerInfos) != 1)) {
goto _Exit;
}
//
// Locate the TimeStamp CounterSignature.
//
SignInfo = sk_PKCS7_SIGNER_INFO_value (SignerInfos, 0);
if (SignInfo == NULL) {
goto _Exit;
}
//
// Locate Message Digest which will be the data to be time-stamped.
//
EncDigest = SignInfo->enc_digest;
if (EncDigest == NULL) {
goto _Exit;
}
//
// The RFC3161 timestamp counterSignature is contained in unauthenticatedAttributes field
// of SignerInfo.
//
Sk = SignInfo->unauth_attr;
if (Sk == NULL) { // No timestamp counterSignature.
goto _Exit;
}
Asn1Type = NULL;
for (Index = 0; Index < (UINTN) sk_X509_ATTRIBUTE_num (Sk); Index++) {
//
// Search valid RFC3161 timestamp counterSignature based on OBJID.
//
Xa = sk_X509_ATTRIBUTE_value (Sk, (int)Index);
if (Xa == NULL) {
continue;
}
XaObj = X509_ATTRIBUTE_get0_object(Xa);
if (XaObj == NULL) {
continue;
}
if ((OBJ_length(XaObj) != sizeof (mSpcRFC3161OidValue)) ||
(CompareMem (OBJ_get0_data(XaObj), mSpcRFC3161OidValue, sizeof (mSpcRFC3161OidValue)) != 0)) {
continue;
}
Asn1Type = X509_ATTRIBUTE_get0_type(Xa, 0);
}
if (Asn1Type == NULL) {
Status = FALSE;
goto _Exit;
}
TSToken = Asn1Type->value.octet_string->data;
TokenSize = Asn1Type->value.octet_string->length;
//
// TimeStamp counterSignature (Token) verification.
//
Status = TimestampTokenVerify (
TSToken,
TokenSize,
TsaCert,
CertSize,
EncDigest->data,
EncDigest->length,
SigningTime
);
_Exit:
//
// Release Resources
//
PKCS7_free (Pkcs7);
return Status;
}