public static void Verify(SignPackageRequest request, ILogger logger)
{
if (request == null)
{
throw new ArgumentNullException(nameof(request));
}
if (logger == null)
{
throw new ArgumentNullException(nameof(logger));
}
if (!CertificateUtility.IsSignatureAlgorithmSupported(request.Certificate))
{
throw new SignatureException(NuGetLogCode.NU3013, Strings.SigningCertificateHasUnsupportedSignatureAlgorithm);
}
if (!CertificateUtility.IsCertificatePublicKeyValid(request.Certificate))
{
throw new SignatureException(NuGetLogCode.NU3014, Strings.SigningCertificateFailsPublicKeyLengthRequirement);
}
if (CertificateUtility.HasExtendedKeyUsage(request.Certificate, Oids.LifetimeSigningEku))
{
throw new SignatureException(NuGetLogCode.NU3015, Strings.ErrorCertificateHasLifetimeSigningEKU);
}
if (CertificateUtility.IsCertificateValidityPeriodInTheFuture(request.Certificate))
{
throw new SignatureException(NuGetLogCode.NU3017, Strings.SignatureNotYetValid);
}
request.BuildSigningCertificateChainOnce(logger);
}
internal static bool IsSigningCertificateValid(X509Certificate2 certificate, bool treatIssuesAsErrors, List <SignatureLog> issues)
{
var isValid = true;
if (!CertificateUtility.IsSignatureAlgorithmSupported(certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3013, Strings.SigningCertificateHasUnsupportedSignatureAlgorithm));
isValid = false;
}
if (!CertificateUtility.IsCertificatePublicKeyValid(certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3014, Strings.SigningCertificateFailsPublicKeyLengthRequirement));
isValid = false;
}
if (CertificateUtility.HasExtendedKeyUsage(certificate, Oids.LifetimeSigningEku))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3015, Strings.ErrorCertificateHasLifetimeSigningEKU));
isValid = false;
}
if (CertificateUtility.IsCertificateValidityPeriodInTheFuture(certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3017, Strings.SignatureNotYetValid));
isValid = false;
}
return(isValid);
}
private static bool IsMatch(
X509Certificate2 certificate,
EssCertIdV2 essCertIdV2,
Errors errors,
bool isIssuerSerialRequired)
{
if (isIssuerSerialRequired)
{
if (essCertIdV2.IssuerSerial == null ||
essCertIdV2.IssuerSerial.GeneralNames.Count == 0)
{
throw new SignatureException(errors.InvalidSignature, errors.InvalidSignatureString);
}
}
if (essCertIdV2.IssuerSerial != null)
{
if (!AreSerialNumbersEqual(essCertIdV2.IssuerSerial, certificate))
{
return(false);
}
if (!AreGeneralNamesEqual(essCertIdV2.IssuerSerial, certificate))
{
return(false);
}
}
var hashAlgorithmName = CryptoHashUtility.OidToHashAlgorithmName(essCertIdV2.HashAlgorithm.Algorithm.Value);
var actualHash = CertificateUtility.GetHash(certificate, hashAlgorithmName);
return(essCertIdV2.CertificateHash.SequenceEqual(actualHash));
}
private Signature CreateSignature(SignPackageRequest request, SignatureContent signatureContent)
{
var cmsSigner = CreateCmsSigner(request);
if (request.PrivateKey != null)
{
return(CreateSignature(cmsSigner, signatureContent, request.PrivateKey));
}
var contentInfo = new ContentInfo(signatureContent.GetBytes());
var cms = new SignedCms(contentInfo);
try
{
cms.ComputeSignature(cmsSigner);
}
catch (CryptographicException ex) when(ex.HResult == INVALID_PROVIDER_TYPE_HRESULT)
{
var exceptionBuilder = new StringBuilder();
exceptionBuilder.AppendLine(Strings.SignFailureCertificateInvalidProviderType);
exceptionBuilder.AppendLine(CertificateUtility.X509Certificate2ToString(request.Certificate));
throw new SignatureException(NuGetLogCode.NU3016, exceptionBuilder.ToString());
}
return(Signature.Load(cms));
}
private static void ValidateTimestampCms(SigningSpecifications spec, SignedCms timestampCms)
{
var signerInfo = timestampCms.SignerInfos[0];
try
{
signerInfo.CheckSignature(verifySignatureOnly: true);
}
catch (Exception e)
{
throw new TimestampException(NuGetLogCode.NU3021, Strings.TimestampSignatureValidationFailed, e);
}
if (!CertificateUtility.IsSignatureAlgorithmSupported(signerInfo.Certificate))
{
throw new TimestampException(NuGetLogCode.NU3022, Strings.TimestampUnsupportedSignatureAlgorithm);
}
if (!CertificateUtility.IsCertificatePublicKeyValid(signerInfo.Certificate))
{
throw new TimestampException(NuGetLogCode.NU3023, Strings.TimestampCertificateFailsPublicKeyLengthRequirement);
}
if (!spec.AllowedHashAlgorithmOids.Contains(signerInfo.DigestAlgorithm.Value))
{
throw new TimestampException(NuGetLogCode.NU3024, Strings.TimestampUnsupportedSignatureAlgorithm);
}
if (CertificateUtility.IsCertificateValidityPeriodInTheFuture(signerInfo.Certificate))
{
throw new TimestampException(NuGetLogCode.NU3025, Strings.TimestampNotYetValid);
}
}
private static PrimarySignature CreatePrimarySignature(CmsSigner cmsSigner, SignPackageRequest request, byte[] signingData)
{
var contentInfo = new ContentInfo(signingData);
var cms = new SignedCms(contentInfo);
try
{
#if IS_DESKTOP
cms.ComputeSignature(cmsSigner);
#else
// In .NET Framework, this parameter is not used and a PIN prompt is always shown. In .NET Core, the silent flag needs to be set to false to show a PIN prompt.
cms.ComputeSignature(cmsSigner, silent: false);
#endif
}
catch (CryptographicException ex) when(ex.HResult == INVALID_PROVIDER_TYPE_HRESULT)
{
var exceptionBuilder = new StringBuilder();
exceptionBuilder.AppendLine(Strings.SignFailureCertificateInvalidProviderType);
exceptionBuilder.AppendLine(CertificateUtility.X509Certificate2ToString(request.Certificate, Common.HashAlgorithmName.SHA256));
throw new SignatureException(NuGetLogCode.NU3001, exceptionBuilder.ToString());
}
return(PrimarySignature.Load(cms));
}
public string GetSigningCertificateFingerprint(HashAlgorithmName algorithm)
{
if (!Enum.IsDefined(typeof(HashAlgorithmName), algorithm))
{
throw new ArgumentException(
string.Format(
CultureInfo.CurrentCulture,
Strings.UnrecognizedEnumValue,
algorithm),
nameof(algorithm));
}
var certificate = SignerInfo.Certificate;
if (certificate == null)
{
throw new InvalidOperationException(string.Format(CultureInfo.CurrentCulture, Strings.Verify_ErrorNoCertificate, FriendlyName));
}
if (_signingCertificateFingerprintLookup == null)
{
_signingCertificateFingerprintLookup = new Dictionary <HashAlgorithmName, string>();
}
if (_signingCertificateFingerprintLookup.TryGetValue(algorithm, out var fingerprint))
{
return(fingerprint);
}
fingerprint = CertificateUtility.GetHashString(certificate, algorithm);
_signingCertificateFingerprintLookup.Add(algorithm, fingerprint);
return(fingerprint);
}
internal static bool IsTimestampValid(Timestamp timestamp, byte[] data, bool treatIssuesAsErrors, List <SignatureLog> issues, SigningSpecifications spec)
{
var isValid = true;
var signerInfo = timestamp.SignerInfo;
if (!timestamp.TstInfo.HasMessageHash(data))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3019, Strings.TimestampIntegrityCheckFailed));
isValid = false;
}
if (timestamp.SignerInfo.Certificate != null)
{
try
{
signerInfo.CheckSignature(verifySignatureOnly: true);
}
catch (Exception e)
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3021, Strings.TimestampSignatureValidationFailed));
issues.Add(SignatureLog.DebugLog(e.ToString()));
isValid = false;
}
if (!CertificateUtility.IsSignatureAlgorithmSupported(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3022, Strings.TimestampUnsupportedSignatureAlgorithm));
isValid = false;
}
if (!CertificateUtility.IsCertificatePublicKeyValid(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3023, Strings.TimestampCertificateFailsPublicKeyLengthRequirement));
isValid = false;
}
if (!spec.AllowedHashAlgorithmOids.Contains(signerInfo.DigestAlgorithm.Value))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3024, Strings.TimestampUnsupportedSignatureAlgorithm));
isValid = false;
}
if (CertificateUtility.IsCertificateValidityPeriodInTheFuture(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3025, Strings.TimestampNotYetValid));
isValid = false;
}
}
else
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3020, Strings.TimestampNoCertificate));
isValid = false;
}
return(isValid);
}
public static EssCertIdV2 Create(X509Certificate2 certificate, Common.HashAlgorithmName hashAlgorithmName)
{
if (certificate == null)
{
throw new ArgumentNullException(nameof(certificate));
}
var algorithm = new AlgorithmIdentifier(hashAlgorithmName.ConvertToOid());
var hash = CertificateUtility.GetHash(certificate, hashAlgorithmName);
var issuerSerial = IssuerSerial.Create(certificate);
return(new EssCertIdV2(algorithm, hash, issuerSerial));
}
private static string GetCertificateFingerprint(
Signature signature,
HashAlgorithmName fingerprintAlgorithm,
IDictionary <HashAlgorithmName, string> CertificateFingerprintLookUp)
{
if (!CertificateFingerprintLookUp.TryGetValue(fingerprintAlgorithm, out var fingerprintString))
{
fingerprintString = CertificateUtility.GetHashString(signature.SignerInfo.Certificate, fingerprintAlgorithm);
CertificateFingerprintLookUp[fingerprintAlgorithm] = fingerprintString;
}
return(fingerprintString);
}
private static string GetCertificateFingerprint(
Signature signature,
HashAlgorithmName fingerprintAlgorithm,
IDictionary <HashAlgorithmName, string> CertificateFingerprintLookUp)
{
if (!CertificateFingerprintLookUp.TryGetValue(fingerprintAlgorithm, out var fingerprintString))
{
var primarySignatureCertificateFingerprint = CertificateUtility.GetHash(signature.SignerInfo.Certificate, fingerprintAlgorithm);
fingerprintString = BitConverter.ToString(primarySignatureCertificateFingerprint).Replace("-", "");
CertificateFingerprintLookUp[fingerprintAlgorithm] = fingerprintString;
}
return(fingerprintString);
}
internal unsafe void AddCountersignature(CmsSigner cmsSigner, CngKey privateKey)
{
using (var hb = new HeapBlockRetainer())
{
var signerInfo = NativeUtility.CreateSignerInfo(cmsSigner, privateKey, hb);
NativeUtility.ThrowIfFailed(NativeMethods.CryptMsgCountersign(
_handle,
dwIndex: 0,
cCountersigners: 1,
rgCountersigners: signerInfo));
AddCertificates(CertificateUtility.GetRawDataForCollection(cmsSigner.Certificates));
}
}
internal static bool BuildCertificateChain(X509Chain chain, X509Certificate2 certificate, out X509ChainStatus[] status)
{
if (certificate == null)
{
throw new ArgumentNullException(nameof(certificate));
}
var buildSuccess = chain.Build(certificate);
status = new X509ChainStatus[chain.ChainStatus.Length];
chain.ChainStatus.CopyTo(status, 0);
// Check if time is not in the future
return(buildSuccess && !CertificateUtility.IsCertificateValidityPeriodInTheFuture(certificate));
}
/// <summary>
/// Get error/warning chain status flags for certificate chain validation during signing.
/// </summary>
/// <param name="certificate">The certificate to verify.</param>
/// <param name="errorStatusFlags">Error chain status flags.</param>
/// <param name="warningStatusFlags">Warning chain status flags.</param>
/// <exception cref="ArgumentNullException">Thrown if <paramref name="certificate" /> is <c>null</c>.</exception>
public static void GetChainStatusFlagsForSigning(
X509Certificate2 certificate,
out X509ChainStatusFlags errorStatusFlags,
out X509ChainStatusFlags warningStatusFlags)
{
if (certificate == null)
{
throw new ArgumentNullException(nameof(certificate));
}
warningStatusFlags = X509ChainStatusFlags.RevocationStatusUnknown | X509ChainStatusFlags.OfflineRevocation;
if (CertificateUtility.IsSelfIssued(certificate))
{
warningStatusFlags |= X509ChainStatusFlags.UntrustedRoot;
}
// Every status flag that isn't a warning is an error.
errorStatusFlags = (~(X509ChainStatusFlags)0) & ~warningStatusFlags;
}
private static PrimarySignature CreatePrimarySignature(CmsSigner cmsSigner, SignPackageRequest request, byte[] signingData)
{
var contentInfo = new ContentInfo(signingData);
var cms = new SignedCms(contentInfo);
try
{
cms.ComputeSignature(cmsSigner);
}
catch (CryptographicException ex) when(ex.HResult == INVALID_PROVIDER_TYPE_HRESULT)
{
var exceptionBuilder = new StringBuilder();
exceptionBuilder.AppendLine(Strings.SignFailureCertificateInvalidProviderType);
exceptionBuilder.AppendLine(CertificateUtility.X509Certificate2ToString(request.Certificate, Common.HashAlgorithmName.SHA256));
throw new SignatureException(NuGetLogCode.NU3001, exceptionBuilder.ToString());
}
return(PrimarySignature.Load(cms));
}
internal static SignatureVerificationStatusFlags ValidateSigningCertificate(X509Certificate2 certificate, bool treatIssuesAsErrors, string signatureFriendlyName, List <SignatureLog> issues)
{
if (certificate == null)
{
throw new ArgumentNullException(nameof(certificate));
}
if (issues == null)
{
throw new ArgumentNullException(nameof(issues));
}
var validationFlags = SignatureVerificationStatusFlags.NoErrors;
if (!CertificateUtility.IsSignatureAlgorithmSupported(certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3013, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_CertificateHasUnsupportedSignatureAlgorithm, signatureFriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.SignatureAlgorithmUnsupported;
}
if (!CertificateUtility.IsCertificatePublicKeyValid(certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3014, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_CertificateFailsPublicKeyLengthRequirement, signatureFriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.CertificatePublicKeyInvalid;
}
if (CertificateUtility.HasExtendedKeyUsage(certificate, Oids.LifetimeSigningEku))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3015, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_CertificateHasLifetimeSigningEKU, signatureFriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.HasLifetimeSigningEku;
}
if (CertificateUtility.IsCertificateValidityPeriodInTheFuture(certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3017, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_CertificateNotYetValid, signatureFriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.CertificateValidityInTheFuture;
}
return(validationFlags);
}
private bool IsSignatureAllowed(Signature signature)
{
// Get information needed for allow list verification
var primarySignatureCertificateFingerprint = CertificateUtility.GetHash(signature.SignerInfo.Certificate, _fingerprintAlgorithm);
var primarySignatureCertificateFingerprintString = BitConverter.ToString(primarySignatureCertificateFingerprint).Replace("-", "");
foreach (var allowedEntry in _allowList)
{
// Verify the certificate hash allow list objects
var certificateHashEntry = allowedEntry as CertificateHashAllowListEntry;
if (certificateHashEntry != null)
{
if (certificateHashEntry.VerificationTarget.HasFlag(VerificationTarget.Primary) &&
StringComparer.OrdinalIgnoreCase.Equals(certificateHashEntry.CertificateFingerprint, primarySignatureCertificateFingerprintString))
{
return(true);
}
}
}
return(false);
}
private static PrimarySignature CreateRepositoryCountersignature(CmsSigner cmsSigner, SignPackageRequest request, PrimarySignature primarySignature)
{
var cms = new SignedCms();
cms.Decode(primarySignature.GetBytes());
try
{
cms.SignerInfos[0].ComputeCounterSignature(cmsSigner);
}
catch (CryptographicException ex) when(ex.HResult == INVALID_PROVIDER_TYPE_HRESULT)
{
var exceptionBuilder = new StringBuilder();
exceptionBuilder.AppendLine(Strings.SignFailureCertificateInvalidProviderType);
exceptionBuilder.AppendLine(CertificateUtility.X509Certificate2ToString(request.Certificate, Common.HashAlgorithmName.SHA256));
throw new SignatureException(NuGetLogCode.NU3001, exceptionBuilder.ToString());
}
return(PrimarySignature.Load(cms));
}
/// <summary>
/// Timestamps data present in the TimestampRequest.
/// </summary>
public byte[] TimestampData(TimestampRequest request, ILogger logger, CancellationToken token)
{
token.ThrowIfCancellationRequested();
if (request == null)
{
throw new ArgumentNullException(nameof(request));
}
if (logger == null)
{
throw new ArgumentNullException(nameof(logger));
}
// Get the signatureValue from the signerInfo object
using (var signatureNativeCms = NativeCms.Decode(request.SignatureValue, detached: false))
{
var signatureValueHashByteArray = NativeCms.GetSignatureValueHash(
request.TimestampHashAlgorithm,
signatureNativeCms);
// Allows us to track the request.
var nonce = GenerateNonce();
var rfc3161TimestampRequest = new Rfc3161TimestampRequest(
signatureValueHashByteArray,
request.TimestampHashAlgorithm.ConvertToSystemSecurityHashAlgorithmName(),
nonce: nonce,
requestSignerCertificates: true);
// Request a timestamp
// The response status need not be checked here as lower level api will throw if the response is invalid
var timestampToken = rfc3161TimestampRequest.SubmitRequest(
_timestamperUrl,
TimeSpan.FromSeconds(_rfc3161RequestTimeoutSeconds));
// ensure response is for this request
ValidateTimestampResponseNonce(nonce, timestampToken);
var timestampCms = timestampToken.AsSignedCms();
byte[] timestampByteArray;
using (var timestampNativeCms = NativeCms.Decode(timestampCms.Encode(), detached: false))
using (var timestampCertChain = new X509Chain())
{
var policy = timestampCertChain.ChainPolicy;
policy.ApplicationPolicy.Add(new Oid(Oids.TimeStampingEkuOid));
policy.VerificationFlags = X509VerificationFlags.IgnoreNotTimeValid;
policy.ExtraStore.AddRange(timestampCms.Certificates);
policy.RevocationFlag = X509RevocationFlag.ExcludeRoot;
policy.RevocationMode = X509RevocationMode.Online;
var timestampSignerCertificate = GetTimestampSignerCertificate(timestampCms);
if (DateTime.Now < timestampSignerCertificate.NotBefore)
{
throw new TimestampException(LogMessage.CreateError(
NuGetLogCode.NU3025,
string.Format(CultureInfo.CurrentCulture,
Strings.TimestampCertificateInvalid,
$"{Environment.NewLine}{CertificateUtility.X509Certificate2ToString(timestampSignerCertificate)}")));
}
if (!timestampCertChain.Build(timestampSignerCertificate))
{
throw new TimestampException(LogMessage.CreateError(
NuGetLogCode.NU3028,
string.Format(CultureInfo.CurrentCulture,
Strings.TimestampCertificateChainBuildFailure,
$"{Environment.NewLine}{CertificateUtility.X509Certificate2ToString(timestampSignerCertificate)}")));
}
// Insert all the certificates into timestampCms
InsertTimestampCertChainIntoTimestampCms(timestampCms, timestampCertChain, timestampNativeCms);
timestampByteArray = timestampCms.Encode();
}
signatureNativeCms.AddTimestamp(timestampByteArray);
return(signatureNativeCms.Encode());
}
}
/// <summary>
/// Verify if the signature object meets the specification trust and validity requirements.
/// </summary>
/// <param name="timestamp">Timestamp for this signature, if signature is not timestamped it can be null.</param>
/// <param name="allowUntrusted">Setting that tells if a signature that does not meet any soft failure requirements can still be allowed. Used to know if warnings or errors should be logged for an issue.</param>
/// <param name="allowUnknownRevocation">Setting that tells if unkown revocation is valid when building the chain.</param>
/// <param name="allowUntrustedSelfSignedCertificate">Setting that tells if an untrusted self-signed certificate should be allowed as the signing certificate.</param>
/// <param name="fingerprintAlgorithm">Algorithm used to calculate and display the certificate's fingerprint.</param>
/// <param name="certificateExtraStore">Collection of certificates to help the chain building engine as an extra store.</param>
/// <param name="issues">List of log messages.</param>
/// <remarks>This is only public for ease of testing</remarks>
/// <returns>Status of trust for signature.</returns>
public virtual SignatureVerificationSummary Verify(
Timestamp timestamp,
SignatureVerifySettings settings,
HashAlgorithmName fingerprintAlgorithm,
X509Certificate2Collection certificateExtraStore)
{
settings = settings ?? SignatureVerifySettings.Default;
var flags = SignatureVerificationStatusFlags.NoErrors;
var issues = new List <SignatureLog>();
SignatureVerificationStatus status;
var certificate = SignerInfo.Certificate;
if (certificate == null)
{
issues.Add(SignatureLog.Issue(!settings.AllowIllegal, NuGetLogCode.NU3010, string.Format(CultureInfo.CurrentCulture, Strings.Verify_ErrorNoCertificate, FriendlyName)));
flags |= SignatureVerificationStatusFlags.NoCertificate;
status = settings.AllowIllegal? SignatureVerificationStatus.Valid: SignatureVerificationStatus.Disallowed;
return(new SignatureVerificationSummary(Type, status, flags, issues));
}
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture,
Strings.VerificationCertDisplay,
FriendlyName,
$"{Environment.NewLine}{CertificateUtility.X509Certificate2ToString(certificate, fingerprintAlgorithm)}")));
try
{
SignerInfo.CheckSignature(verifySignatureOnly: true);
}
catch (Exception e)
{
issues.Add(SignatureLog.Issue(!settings.AllowIllegal, NuGetLogCode.NU3012, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_SignatureVerificationFailed, FriendlyName)));
issues.Add(SignatureLog.DebugLog(e.ToString()));
flags |= SignatureVerificationStatusFlags.SignatureCheckFailed;
status = settings.AllowIllegal ? SignatureVerificationStatus.Valid : SignatureVerificationStatus.Disallowed;
return(new SignatureVerificationSummary(Type, status, flags, issues));
}
DateTimeOffset?expirationTime = null;
var certificateFlags = VerificationUtility.ValidateSigningCertificate(certificate, !settings.AllowIllegal, FriendlyName, issues);
if (certificateFlags != SignatureVerificationStatusFlags.NoErrors)
{
flags |= certificateFlags;
}
else
{
timestamp = timestamp ?? new Timestamp();
using (var chainHolder = new X509ChainHolder())
{
var chain = chainHolder.Chain;
// This flag should only be set for verification scenarios, not signing.
chain.ChainPolicy.VerificationFlags = X509VerificationFlags.IgnoreNotTimeValid;
CertificateChainUtility.SetCertBuildChainPolicy(chain.ChainPolicy, certificateExtraStore, timestamp.UpperLimit.LocalDateTime, CertificateType.Signature);
if (settings.RevocationMode == RevocationMode.Offline)
{
chain.ChainPolicy.RevocationMode = X509RevocationMode.Offline;
}
else
{
chain.ChainPolicy.RevocationMode = X509RevocationMode.Online;
}
var chainBuildingSucceeded = CertificateChainUtility.BuildCertificateChain(chain, certificate, out var chainStatuses);
var x509ChainString = CertificateUtility.X509ChainToString(chain, fingerprintAlgorithm);
if (!string.IsNullOrWhiteSpace(x509ChainString))
{
issues.Add(SignatureLog.DetailedLog(x509ChainString));
}
var chainBuildingHasIssues = false;
if (!chainBuildingSucceeded)
{
var statusFlags = CertificateChainUtility.DefaultObservedStatusFlags;
IEnumerable <string> messages;
if (CertificateChainUtility.TryGetStatusMessage(chainStatuses, statusFlags, out messages))
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(!settings.AllowIllegal, NuGetLogCode.NU3012, string.Format(CultureInfo.CurrentCulture, Strings.VerifyChainBuildingIssue, FriendlyName, message)));
}
chainBuildingHasIssues = true;
flags |= SignatureVerificationStatusFlags.ChainBuildingFailure;
}
// For all the special cases, chain status list only has unique elements for each chain status flag present
// therefore if we are checking for one specific chain status we can use the first of the returned list
// if we are combining checks for more than one, then we have to use the whole list.
if (CertificateChainUtility.TryGetStatusMessage(chainStatuses, X509ChainStatusFlags.Revoked, out messages))
{
issues.Add(SignatureLog.Error(NuGetLogCode.NU3012, string.Format(CultureInfo.CurrentCulture, Strings.VerifyChainBuildingIssue, FriendlyName, messages.First())));
flags |= SignatureVerificationStatusFlags.CertificateRevoked;
return(new SignatureVerificationSummary(Type, SignatureVerificationStatus.Suspect, flags, timestamp, issues));
}
if (CertificateChainUtility.TryGetStatusMessage(chainStatuses, X509ChainStatusFlags.UntrustedRoot, out messages))
{
if (settings.ReportUntrustedRoot)
{
issues.Add(SignatureLog.Issue(!settings.AllowUntrusted, NuGetLogCode.NU3018, string.Format(CultureInfo.CurrentCulture, Strings.VerifyChainBuildingIssue, FriendlyName, messages.First())));
}
if (!settings.AllowUntrusted)
{
chainBuildingHasIssues = true;
flags |= SignatureVerificationStatusFlags.UntrustedRoot;
}
}
var offlineRevocationErrors = CertificateChainUtility.TryGetStatusMessage(chainStatuses, X509ChainStatusFlags.OfflineRevocation, out var _);
var unknownRevocationErrors = CertificateChainUtility.TryGetStatusMessage(chainStatuses, X509ChainStatusFlags.RevocationStatusUnknown, out var unknownRevocationStatusMessages);
if (offlineRevocationErrors || unknownRevocationErrors)
{
if (settings.ReportUnknownRevocation)
{
string unknownRevocationMessage = null;
if (unknownRevocationErrors)
{
unknownRevocationMessage = string.Format(CultureInfo.CurrentCulture, Strings.VerifyChainBuildingIssue, FriendlyName, unknownRevocationStatusMessages.First());
}
if (settings.RevocationMode == RevocationMode.Offline)
{
if (offlineRevocationErrors)
{
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture, Strings.VerifyChainBuildingIssue, FriendlyName, Strings.VerifyCertTrustOfflineWhileRevocationModeOffline)));
}
if (unknownRevocationMessage != null)
{
issues.Add(SignatureLog.InformationLog(unknownRevocationMessage));
}
}
else
{
if (offlineRevocationErrors)
{
issues.Add(SignatureLog.Issue(!settings.AllowUnknownRevocation, NuGetLogCode.NU3018, string.Format(CultureInfo.CurrentCulture, Strings.VerifyChainBuildingIssue, FriendlyName, Strings.VerifyCertTrustOfflineWhileRevocationModeOnline)));
}
if (unknownRevocationMessage != null)
{
issues.Add(SignatureLog.Issue(!settings.AllowUnknownRevocation, NuGetLogCode.NU3018, unknownRevocationMessage));
}
}
}
if (!settings.AllowUnknownRevocation)
{
chainBuildingHasIssues = true;
flags |= SignatureVerificationStatusFlags.UnknownRevocation;
}
}
// Debug log any errors
issues.Add(SignatureLog.DebugLog(
string.Format(
CultureInfo.CurrentCulture,
Strings.VerifyError_InvalidCertificateChain,
FriendlyName,
string.Join(", ", chainStatuses.Select(x => x.Status.ToString())))));
}
var isSignatureTimeValid = Rfc3161TimestampVerificationUtility.ValidateSignerCertificateAgainstTimestamp(certificate, timestamp);
if (isSignatureTimeValid && !chainBuildingHasIssues)
{
return(new SignatureVerificationSummary(Type, SignatureVerificationStatus.Valid, flags, timestamp, issues));
}
else if (!isSignatureTimeValid)
{
issues.Add(
SignatureLog.Issue(
!settings.AllowUntrusted,
NuGetLogCode.NU3037,
string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_SignatureNotTimeValid, FriendlyName)));
if (!settings.AllowUntrusted)
{
flags |= SignatureVerificationStatusFlags.CertificateExpired;
}
expirationTime = DateTime.SpecifyKind(certificate.NotAfter, DateTimeKind.Local);
}
}
}
status = VerificationUtility.GetSignatureVerificationStatus(flags);
return(new SignatureVerificationSummary(Type, status, flags, timestamp, expirationTime, issues));
}
/// <summary>
/// Verify if the timestamp object meets the specification requirements.
/// </summary>
/// <param name="signature">Signature which this timestamp is for.</param>
/// <param name="allowIgnoreTimestamp">Setting that tells if a timestamp can be ignored if it doesn't meet the requirements. Used to know if warnings or errors should be logged for an issue.</param>
/// <param name="allowUnknownRevocation">Setting that tells if unkown revocation is valid when building the chain.</param>
/// <param name="issues">List of log messages.</param>
/// <returns>true if the timestamp meets the requierements, false otherwise.</returns>
internal SignatureVerificationStatusFlags Verify(
Signature signature,
SignedPackageVerifierSettings settings,
HashAlgorithmName fingerprintAlgorithm,
List <SignatureLog> issues)
{
settings = settings ?? SignedPackageVerifierSettings.GetDefault();
var flags = SignatureVerificationStatusFlags.NoErrors;
if (signature == null)
{
throw new ArgumentNullException(nameof(signature));
}
if (issues == null)
{
throw new ArgumentNullException(nameof(issues));
}
var treatIssueAsError = !settings.AllowIgnoreTimestamp;
var timestamperCertificate = SignerInfo.Certificate;
if (timestamperCertificate == null)
{
flags |= SignatureVerificationStatusFlags.NoCertificate;
issues.Add(SignatureLog.Issue(treatIssueAsError, NuGetLogCode.NU3020, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampNoCertificate, signature.FriendlyName)));
return(flags);
}
flags |= VerificationUtility.ValidateTimestamp(this, signature, treatIssueAsError, issues, SigningSpecifications.V1);
if (flags == SignatureVerificationStatusFlags.NoErrors)
{
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture, Strings.TimestampValue, GeneralizedTime.LocalDateTime.ToString()) + Environment.NewLine));
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture,
Strings.VerificationTimestamperCertDisplay,
signature.FriendlyName,
$"{Environment.NewLine}{CertificateUtility.X509Certificate2ToString(timestamperCertificate, fingerprintAlgorithm)}")));
var certificateExtraStore = SignedCms.Certificates;
using (var chainHolder = new X509ChainHolder())
{
var chain = chainHolder.Chain;
// This flag should only be set for verification scenarios, not signing.
chain.ChainPolicy.VerificationFlags = X509VerificationFlags.IgnoreNotTimeValid;
CertificateChainUtility.SetCertBuildChainPolicy(chain.ChainPolicy, certificateExtraStore, DateTime.Now, CertificateType.Timestamp);
if (settings.RevocationMode == RevocationMode.Offline)
{
chain.ChainPolicy.RevocationMode = X509RevocationMode.Offline;
}
else
{
chain.ChainPolicy.RevocationMode = X509RevocationMode.Online;
}
var chainBuildSucceed = CertificateChainUtility.BuildCertificateChain(chain, timestamperCertificate, out var chainStatusList);
var x509ChainString = CertificateUtility.X509ChainToString(chain, fingerprintAlgorithm);
if (!string.IsNullOrWhiteSpace(x509ChainString))
{
issues.Add(SignatureLog.DetailedLog(x509ChainString));
}
if (chainBuildSucceed)
{
return(flags);
}
var chainBuildingHasIssues = false;
IEnumerable <string> messages;
var timestampInvalidCertificateFlags = CertificateChainUtility.DefaultObservedStatusFlags;
if (CertificateChainUtility.TryGetStatusMessage(chainStatusList, timestampInvalidCertificateFlags, out messages))
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(treatIssueAsError, NuGetLogCode.NU3028, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampVerifyChainBuildingIssue, signature.FriendlyName, message)));
}
flags |= SignatureVerificationStatusFlags.ChainBuildingFailure;
chainBuildingHasIssues = true;
}
// For all the special cases, chain status list only has unique elements for each chain status flag present
// therefore if we are checking for one specific chain status we can use the first of the returned list
// if we are combining checks for more than one, then we have to use the whole list.
if (CertificateChainUtility.TryGetStatusMessage(chainStatusList, X509ChainStatusFlags.UntrustedRoot, out messages))
{
issues.Add(SignatureLog.Error(NuGetLogCode.NU3028, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampVerifyChainBuildingIssue, signature.FriendlyName, messages.First())));
flags |= SignatureVerificationStatusFlags.UntrustedRoot;
chainBuildingHasIssues = true;
}
if (CertificateChainUtility.TryGetStatusMessage(chainStatusList, X509ChainStatusFlags.Revoked, out messages))
{
issues.Add(SignatureLog.Error(NuGetLogCode.NU3028, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampVerifyChainBuildingIssue, signature.FriendlyName, messages.First())));
flags |= SignatureVerificationStatusFlags.CertificateRevoked;
return(flags);
}
var offlineRevocationErrors = CertificateChainUtility.TryGetStatusMessage(chainStatusList, X509ChainStatusFlags.OfflineRevocation, out var _);
var unknownRevocationErrors = CertificateChainUtility.TryGetStatusMessage(chainStatusList, X509ChainStatusFlags.RevocationStatusUnknown, out var unknownRevocationStatusMessages);
if (offlineRevocationErrors || unknownRevocationErrors)
{
if (treatIssueAsError)
{
string unknownRevocationMessage = null;
if (unknownRevocationErrors)
{
unknownRevocationMessage = string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampVerifyChainBuildingIssue, signature.FriendlyName, unknownRevocationStatusMessages.First());
}
if (settings.RevocationMode == RevocationMode.Offline)
{
if (offlineRevocationErrors)
{
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampVerifyChainBuildingIssue, signature.FriendlyName, Strings.VerifyCertTrustOfflineWhileRevocationModeOffline)));
}
if (unknownRevocationMessage != null)
{
issues.Add(SignatureLog.InformationLog(unknownRevocationMessage));
}
}
else
{
if (offlineRevocationErrors)
{
issues.Add(SignatureLog.Issue(!settings.AllowUnknownRevocation, NuGetLogCode.NU3018, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampVerifyChainBuildingIssue, signature.FriendlyName, Strings.VerifyCertTrustOfflineWhileRevocationModeOnline)));
}
if (unknownRevocationMessage != null)
{
issues.Add(SignatureLog.Issue(!settings.AllowUnknownRevocation, NuGetLogCode.NU3018, unknownRevocationMessage));
}
}
}
if (!chainBuildingHasIssues && (settings.AllowIgnoreTimestamp || settings.AllowUnknownRevocation))
{
return(flags);
}
flags |= SignatureVerificationStatusFlags.UnknownRevocation;
chainBuildingHasIssues = true;
}
// Debug log any errors
issues.Add(
SignatureLog.DebugLog(
string.Format(
CultureInfo.CurrentCulture,
$"{signature.FriendlyName}'s timestamp",
Strings.VerifyError_InvalidCertificateChain,
string.Join(", ", chainStatusList.Select(x => x.Status.ToString())))));
}
}
return(flags);
}
private SignatureVerificationStatus VerifySignature(Signature signature, Timestamp timestamp, bool failuresAreFatal, List <SignatureLog> issues)
{
var certificate = signature.SignerInfo.Certificate;
if (certificate != null)
{
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture,
Strings.VerificationAuthorCertDisplay,
$"{Environment.NewLine}{CertificateUtility.X509Certificate2ToString(certificate)}")));
try
{
signature.SignerInfo.CheckSignature(verifySignatureOnly: true);
}
catch (Exception e)
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3012, Strings.ErrorSignatureVerificationFailed));
issues.Add(SignatureLog.DebugLog(e.ToString()));
return(SignatureVerificationStatus.Invalid);
}
if (!SigningUtility.IsCertificateValidityPeriodInTheFuture(certificate))
{
timestamp = timestamp ?? new Timestamp();
if (Rfc3161TimestampVerificationUtility.ValidateSignerCertificateAgainstTimestamp(certificate, timestamp))
{
// Read signed attribute containing the original cert hashes
// var signingCertificateAttribute = signature.SignerInfo.SignedAttributes.GetAttributeOrDefault(Oids.SigningCertificateV2);
// TODO: how are we going to use the signingCertificateAttribute?
var certificateExtraStore = signature.SignedCms.Certificates;
using (var chain = new X509Chain())
{
// This flags should only be set for verification scenarios, not signing
chain.ChainPolicy.VerificationFlags = X509VerificationFlags.IgnoreNotTimeValid | X509VerificationFlags.IgnoreCtlNotTimeValid;
SigningUtility.SetCertBuildChainPolicy(chain.ChainPolicy, certificateExtraStore, timestamp.UpperLimit.LocalDateTime, NuGetVerificationCertificateType.Signature);
var chainBuildingSucceed = SigningUtility.BuildCertificateChain(chain, certificate, out var chainStatusList);
issues.Add(SignatureLog.DetailedLog(CertificateUtility.X509ChainToString(chain)));
if (chainBuildingSucceed)
{
return(SignatureVerificationStatus.Trusted);
}
var chainBuildingHasIssues = false;
IReadOnlyList <string> messages;
if (SigningUtility.TryGetStatusMessage(chainStatusList, SigningUtility.NotIgnoredCertificateFlags, out messages))
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3018, message));
}
chainBuildingHasIssues = true;
}
// For all the special cases, chain status list only has unique elements for each chain status flag present
// therefore if we are checking for one specific chain status we can use the first of the returned list
// if we are combining checks for more than one, then we have to use the whole list.
IReadOnlyList <X509ChainStatus> chainStatus = null;
if (SigningUtility.ChainStatusListIncludesStatus(chainStatusList, X509ChainStatusFlags.Revoked, out chainStatus))
{
var status = chainStatus.First();
issues.Add(SignatureLog.Issue(true, NuGetLogCode.NU3018, status.StatusInformation));
return(SignatureVerificationStatus.Invalid);
}
const X509ChainStatusFlags RevocationStatusFlags = X509ChainStatusFlags.RevocationStatusUnknown | X509ChainStatusFlags.OfflineRevocation;
if (SigningUtility.TryGetStatusMessage(chainStatusList, RevocationStatusFlags, out messages))
{
if (failuresAreFatal)
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3018, message));
}
}
else if (!chainBuildingHasIssues)
{
return(SignatureVerificationStatus.Trusted);
}
chainBuildingHasIssues = true;
}
// Debug log any errors
issues.Add(SignatureLog.DebugLog(string.Format(CultureInfo.CurrentCulture, Strings.ErrorInvalidCertificateChain, string.Join(", ", chainStatusList.Select(x => x.ToString())))));
}
}
else
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3012, Strings.ErrorSignatureVerificationFailed));
}
}
else
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3017, Strings.SignatureNotYetValid));
}
}
else
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3010, Strings.ErrorNoCertificate));
}
return(SignatureVerificationStatus.Untrusted);
}
/// <summary>
/// Validates a SignedCms object containing a timestamp response.
/// </summary>
/// <param name="timestampCms">SignedCms response from the timestamp authority.</param>
/// <param name="messageHash">Message hash that was signed and timestamped.</param>
private bool IsTimestampValid(Timestamp timestamp, byte[] messageHash, bool failuresAreFatal, List <SignatureLog> issues)
{
var timestamperCertificate = timestamp.SignerInfo.Certificate;
if (timestamperCertificate == null)
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3020, Strings.TimestampNoCertificate));
return(false);
}
if (SigningUtility.IsTimestampValid(timestamp, messageHash, failuresAreFatal, issues, _specification))
{
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture, Strings.TimestampValue, timestamp.GeneralizedTime.LocalDateTime.ToString()) + Environment.NewLine));
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture,
Strings.VerificationTimestamperCertDisplay,
$"{Environment.NewLine}{CertificateUtility.X509Certificate2ToString(timestamperCertificate)}")));
//var signingCertificateAttribute = timestampSignerInfo.SignedAttributes.GetAttributeOrDefault(Oids.SigningCertificate);
//if (signingCertificateAttribute == null)
//{
// signingCertificateAttribute = timestampSignerInfo.SignedAttributes.GetAttributeOrDefault(Oids.SigningCertificateV2);
//}
// TODO: how are we going to use the signingCertificateAttribute?
var certificateExtraStore = timestamp.SignedCms.Certificates;
using (var chain = new X509Chain())
{
// This flags should only be set for verification scenarios, not signing
chain.ChainPolicy.VerificationFlags = X509VerificationFlags.IgnoreNotTimeValid | X509VerificationFlags.IgnoreCtlNotTimeValid;
SigningUtility.SetCertBuildChainPolicy(chain.ChainPolicy, certificateExtraStore, DateTime.Now, NuGetVerificationCertificateType.Timestamp);
var chainBuildSucceed = SigningUtility.BuildCertificateChain(chain, timestamperCertificate, out var chainStatusList);
issues.Add(SignatureLog.DetailedLog(CertificateUtility.X509ChainToString(chain)));
if (chainBuildSucceed)
{
return(true);
}
var chainBuildingHasIssues = false;
IReadOnlyList <string> messages;
var timestampInvalidCertificateFlags = SigningUtility.NotIgnoredCertificateFlags |
(X509ChainStatusFlags.Revoked) |
(X509ChainStatusFlags.NotTimeValid) |
(X509ChainStatusFlags.CtlNotTimeValid);
if (SigningUtility.TryGetStatusMessage(chainStatusList, timestampInvalidCertificateFlags, out messages))
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3028, message));
}
chainBuildingHasIssues = true;
}
// For all the special cases, chain status list only has unique elements for each chain status flag present
// therefore if we are checking for one specific chain status we can use the first of the returned list
// if we are combining checks for more than one, then we have to use the whole list.
const X509ChainStatusFlags RevocationStatusFlags = X509ChainStatusFlags.RevocationStatusUnknown | X509ChainStatusFlags.OfflineRevocation;
if (SigningUtility.TryGetStatusMessage(chainStatusList, RevocationStatusFlags, out messages))
{
if (failuresAreFatal)
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(failuresAreFatal, NuGetLogCode.NU3028, message));
}
}
else if (!chainBuildingHasIssues)
{
return(true);
}
chainBuildingHasIssues = true;
}
// Debug log any errors
issues.Add(SignatureLog.DebugLog(string.Format(CultureInfo.CurrentCulture, Strings.ErrorInvalidCertificateChain, string.Join(", ", chainStatusList.Select(x => x.ToString())))));
}
}
return(false);
}
internal static SignatureVerificationStatusFlags ValidateTimestamp(Timestamp timestamp, Signature signature, bool treatIssuesAsErrors, List <SignatureLog> issues, SigningSpecifications spec)
{
if (timestamp == null)
{
throw new ArgumentNullException(nameof(timestamp));
}
if (signature == null)
{
throw new ArgumentNullException(nameof(signature));
}
if (issues == null)
{
throw new ArgumentNullException(nameof(issues));
}
// Default to specification v1
spec = spec ?? SigningSpecifications.V1;
var validationFlags = SignatureVerificationStatusFlags.NoErrors;
var signerInfo = timestamp.SignerInfo;
if (timestamp.SignerInfo.Certificate != null)
{
try
{
signerInfo.CheckSignature(verifySignatureOnly: true);
}
catch (Exception e)
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3021, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampSignatureValidationFailed, signature.FriendlyName)));
issues.Add(SignatureLog.DebugLog(e.ToString()));
validationFlags |= SignatureVerificationStatusFlags.SignatureCheckFailed;
}
if (!CertificateUtility.IsSignatureAlgorithmSupported(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3022, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampUnsupportedSignatureAlgorithm, signature.FriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.SignatureAlgorithmUnsupported;
}
if (!CertificateUtility.IsCertificatePublicKeyValid(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3023, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampCertificateFailsPublicKeyLengthRequirement, signature.FriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.CertificatePublicKeyInvalid;
}
if (!spec.AllowedHashAlgorithmOids.Contains(signerInfo.DigestAlgorithm.Value))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3024, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampUnsupportedSignatureAlgorithm, signature.FriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.HashAlgorithmUnsupported;
}
try
{
var hashAlgorithm = CryptoHashUtility.OidToHashAlgorithmName(timestamp.TstInfo.HashAlgorithmId.Value);
var signatureValue = signature.GetSignatureValue();
var messageHash = hashAlgorithm.ComputeHash(signatureValue);
if (!timestamp.TstInfo.HasMessageHash(messageHash))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3019, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampIntegrityCheckFailed, signature.FriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.IntegrityCheckFailed;
}
}
catch
{
// If the hash algorithm is not supported OidToHashAlgorithmName will throw
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3030, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampMessageImprintUnsupportedHashAlgorithm, signature.FriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.MessageImprintUnsupportedAlgorithm;
}
if (CertificateUtility.IsCertificateValidityPeriodInTheFuture(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3025, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampNotYetValid, signature.FriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.CertificateValidityInTheFuture;
}
if (!CertificateUtility.IsDateInsideValidityPeriod(signerInfo.Certificate, timestamp.GeneralizedTime))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3036, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampGeneralizedTimeInvalid, signature.FriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.GeneralizedTimeOutsideValidity;
}
}
else
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3020, string.Format(CultureInfo.CurrentCulture, Strings.VerifyError_TimestampNoCertificate, signature.FriendlyName)));
validationFlags |= SignatureVerificationStatusFlags.NoCertificate;
}
return(validationFlags);
}
internal static bool IsTimestampValid(Timestamp timestamp, Signature signature, bool treatIssuesAsErrors, List <SignatureLog> issues, SigningSpecifications spec)
{
if (timestamp == null)
{
throw new ArgumentNullException(nameof(timestamp));
}
if (signature == null)
{
throw new ArgumentNullException(nameof(signature));
}
if (issues == null)
{
throw new ArgumentNullException(nameof(issues));
}
// Default to specification v1
spec = spec ?? SigningSpecifications.V1;
var isValid = true;
var signerInfo = timestamp.SignerInfo;
if (timestamp.SignerInfo.Certificate != null)
{
try
{
signerInfo.CheckSignature(verifySignatureOnly: true);
}
catch (Exception e)
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3021, Strings.TimestampSignatureValidationFailed));
issues.Add(SignatureLog.DebugLog(e.ToString()));
isValid = false;
}
if (!CertificateUtility.IsSignatureAlgorithmSupported(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3022, Strings.TimestampUnsupportedSignatureAlgorithm));
isValid = false;
}
if (!CertificateUtility.IsCertificatePublicKeyValid(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3023, Strings.TimestampCertificateFailsPublicKeyLengthRequirement));
isValid = false;
}
if (!spec.AllowedHashAlgorithmOids.Contains(signerInfo.DigestAlgorithm.Value))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3024, Strings.TimestampUnsupportedSignatureAlgorithm));
isValid = false;
}
try
{
var hashAlgorithm = CryptoHashUtility.OidToHashAlgorithmName(timestamp.TstInfo.HashAlgorithmId.Value);
var signatureValue = signature.GetSignatureValue();
var messageHash = hashAlgorithm.ComputeHash(signatureValue);
if (!timestamp.TstInfo.HasMessageHash(messageHash))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3019, Strings.TimestampIntegrityCheckFailed));
isValid = false;
}
}
catch
{
// If the hash algorithm is not supported OidToHashAlgorithmName will throw
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3030, Strings.TimestampMessageImprintUnsupportedHashAlgorithm));
isValid = false;
}
if (CertificateUtility.IsCertificateValidityPeriodInTheFuture(signerInfo.Certificate))
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3025, Strings.TimestampNotYetValid));
isValid = false;
}
}
else
{
issues.Add(SignatureLog.Issue(treatIssuesAsErrors, NuGetLogCode.NU3020, Strings.TimestampNoCertificate));
isValid = false;
}
return(isValid);
}
/// <summary>
/// Verify if the signature object meets the specification trust and validity requirements.
/// </summary>
/// <param name="timestamp">Timestamp for this signature, if signature is not timestamped it can be null.</param>
/// <param name="allowUntrusted">Setting that tells if a signature that does not meet any soft failure requirements can still be allowed. Used to know if warnings or errors should be logged for an issue.</param>
/// <param name="allowUnknownRevocation">Setting that tells if unkown revocation is valid when building the chain.</param>
/// <param name="allowUntrustedSelfSignedCertificate">Setting that tells if an untrusted self-signed certificate should be allowed as the signing certificate.</param>
/// <param name="fingerprintAlgorithm">Algorithm used to calculate and display the certificate's fingerprint.</param>
/// <param name="certificateExtraStore">Collection of certificates to help the chain building engine as an extra store.</param>
/// <param name="issues">List of log messages.</param>
/// <returns>Status of trust for signature.</returns>
internal virtual SignatureVerificationStatus Verify(
Timestamp timestamp,
SignedPackageVerifierSettings settings,
HashAlgorithmName fingerprintAlgorithm,
X509Certificate2Collection certificateExtraStore,
List <SignatureLog> issues)
{
if (issues == null)
{
throw new ArgumentNullException(nameof(issues));
}
settings = settings ?? SignedPackageVerifierSettings.Default;
var treatIssueAsError = !settings.AllowUntrusted;
var certificate = SignerInfo.Certificate;
if (certificate == null)
{
issues.Add(SignatureLog.Issue(treatIssueAsError, NuGetLogCode.NU3010, Strings.ErrorNoCertificate));
return(SignatureVerificationStatus.Invalid);
}
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture,
Strings.VerificationAuthorCertDisplay,
$"{Environment.NewLine}{CertificateUtility.X509Certificate2ToString(certificate, fingerprintAlgorithm)}")));
try
{
SignerInfo.CheckSignature(verifySignatureOnly: true);
}
catch (Exception e)
{
issues.Add(SignatureLog.Issue(treatIssueAsError, NuGetLogCode.NU3012, Strings.ErrorSignatureVerificationFailed));
issues.Add(SignatureLog.DebugLog(e.ToString()));
return(SignatureVerificationStatus.Invalid);
}
if (VerificationUtility.IsSigningCertificateValid(certificate, treatIssueAsError, issues))
{
timestamp = timestamp ?? new Timestamp();
if (Rfc3161TimestampVerificationUtility.ValidateSignerCertificateAgainstTimestamp(certificate, timestamp))
{
using (var chainHolder = new X509ChainHolder())
{
var chain = chainHolder.Chain;
// These flags should only be set for verification scenarios not signing
chain.ChainPolicy.VerificationFlags = X509VerificationFlags.IgnoreNotTimeValid | X509VerificationFlags.IgnoreCtlNotTimeValid;
CertificateChainUtility.SetCertBuildChainPolicy(chain.ChainPolicy, certificateExtraStore, timestamp.UpperLimit.LocalDateTime, CertificateType.Signature);
var chainBuildingSucceed = CertificateChainUtility.BuildCertificateChain(chain, certificate, out var chainStatuses);
issues.Add(SignatureLog.DetailedLog(CertificateUtility.X509ChainToString(chain, fingerprintAlgorithm)));
if (chainBuildingSucceed)
{
return(SignatureVerificationStatus.Trusted);
}
var chainBuildingHasIssues = false;
var statusFlags = CertificateChainUtility.DefaultObservedStatusFlags;
var isSelfSignedCertificate = CertificateUtility.IsSelfIssued(certificate);
if (isSelfSignedCertificate)
{
statusFlags &= ~X509ChainStatusFlags.UntrustedRoot;
}
IEnumerable <string> messages;
if (CertificateChainUtility.TryGetStatusMessage(chainStatuses, statusFlags, out messages))
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(treatIssueAsError, NuGetLogCode.NU3012, message));
}
chainBuildingHasIssues = true;
}
// For all the special cases, chain status list only has unique elements for each chain status flag present
// therefore if we are checking for one specific chain status we can use the first of the returned list
// if we are combining checks for more than one, then we have to use the whole list.
IEnumerable <X509ChainStatus> chainStatus = null;
if (CertificateChainUtility.ChainStatusListIncludesStatus(chainStatuses, X509ChainStatusFlags.Revoked, out chainStatus))
{
var status = chainStatus.First();
issues.Add(SignatureLog.Error(NuGetLogCode.NU3012, status.StatusInformation));
return(SignatureVerificationStatus.Invalid);
}
if (isSelfSignedCertificate &&
CertificateChainUtility.TryGetStatusMessage(chainStatuses, X509ChainStatusFlags.UntrustedRoot, out messages))
{
issues.Add(SignatureLog.Issue(!settings.AllowUntrustedSelfIssuedCertificate, NuGetLogCode.NU3018, messages.First()));
if (!chainBuildingHasIssues && settings.AllowUntrustedSelfIssuedCertificate)
{
return(SignatureVerificationStatus.Trusted);
}
}
const X509ChainStatusFlags RevocationStatusFlags = X509ChainStatusFlags.RevocationStatusUnknown | X509ChainStatusFlags.OfflineRevocation;
if (CertificateChainUtility.TryGetStatusMessage(chainStatuses, RevocationStatusFlags, out messages))
{
if (treatIssueAsError)
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(!settings.AllowUnknownRevocation, NuGetLogCode.NU3018, message));
}
}
if (!chainBuildingHasIssues && settings.AllowUnknownRevocation)
{
return(SignatureVerificationStatus.Trusted);
}
chainBuildingHasIssues = true;
}
// Debug log any errors
issues.Add(SignatureLog.DebugLog(
string.Format(
CultureInfo.CurrentCulture,
Strings.ErrorInvalidCertificateChain,
string.Join(", ", chainStatuses.Select(x => x.Status.ToString())))));
}
}
else
{
issues.Add(SignatureLog.Issue(treatIssueAsError, NuGetLogCode.NU3011, Strings.SignatureNotTimeValid));
}
}
return(SignatureVerificationStatus.Untrusted);
}
private static void ValidateTimestampCms(SigningSpecifications spec, SignedCms timestampCms, IRfc3161TimestampToken timestampToken)
{
var signerInfo = timestampCms.SignerInfos[0];
try
{
signerInfo.CheckSignature(verifySignatureOnly: true);
}
catch (Exception e)
{
throw new TimestampException(NuGetLogCode.NU3021, Strings.SignError_TimestampSignatureValidationFailed, e);
}
if (signerInfo.Certificate == null)
{
throw new TimestampException(NuGetLogCode.NU3020, Strings.SignError_TimestampNoCertificate);
}
if (!CertificateUtility.IsSignatureAlgorithmSupported(signerInfo.Certificate))
{
var certificateSignatureAlgorithm = GetNameOrOidString(signerInfo.Certificate.SignatureAlgorithm);
var supportedSignatureAlgorithms = string.Join(", ", spec.AllowedSignatureAlgorithms);
var errorMessage = string.Format(CultureInfo.CurrentCulture,
Strings.TimestampCertificateUnsupportedSignatureAlgorithm,
certificateSignatureAlgorithm,
supportedSignatureAlgorithms);
throw new TimestampException(NuGetLogCode.NU3022, errorMessage);
}
if (!CertificateUtility.IsCertificatePublicKeyValid(signerInfo.Certificate))
{
throw new TimestampException(NuGetLogCode.NU3023, Strings.SignError_TimestampCertificateFailsPublicKeyLengthRequirement);
}
if (!spec.AllowedHashAlgorithmOids.Contains(signerInfo.DigestAlgorithm.Value))
{
var digestAlgorithm = GetNameOrOidString(signerInfo.DigestAlgorithm);
var supportedSignatureAlgorithms = string.Join(", ", spec.AllowedHashAlgorithms);
var errorMessage = string.Format(CultureInfo.CurrentCulture,
Strings.TimestampSignatureUnsupportedDigestAlgorithm,
digestAlgorithm,
supportedSignatureAlgorithms);
throw new TimestampException(NuGetLogCode.NU3024, errorMessage);
}
if (CertificateUtility.IsCertificateValidityPeriodInTheFuture(signerInfo.Certificate))
{
throw new TimestampException(NuGetLogCode.NU3025, Strings.SignError_TimestampNotYetValid);
}
if (!CertificateUtility.IsDateInsideValidityPeriod(signerInfo.Certificate, timestampToken.TokenInfo.Timestamp))
{
throw new TimestampException(NuGetLogCode.NU3036, Strings.SignError_TimestampGeneralizedTimeInvalid);
}
}
/// <summary>
/// Verify if the timestamp object meets the specification requirements.
/// </summary>
/// <param name="signature">Signature which this timestamp is for.</param>
/// <param name="allowIgnoreTimestamp">Setting that tells if a timestamp can be ignored if it doesn't meet the requirements. Used to know if warnings or errors should be logged for an issue.</param>
/// <param name="allowUnknownRevocation">Setting that tells if unkown revocation is valid when building the chain.</param>
/// <param name="issues">List of log messages.</param>
/// <returns>true if the timestamp meets the requierements, false otherwise.</returns>
internal bool Verify(
Signature signature,
SignedPackageVerifierSettings settings,
HashAlgorithmName fingerprintAlgorithm,
List <SignatureLog> issues)
{
settings = settings ?? SignedPackageVerifierSettings.GetDefault();
if (signature == null)
{
throw new ArgumentNullException(nameof(signature));
}
if (issues == null)
{
throw new ArgumentNullException(nameof(issues));
}
var treatIssueAsError = !settings.AllowIgnoreTimestamp;
var timestamperCertificate = SignerInfo.Certificate;
if (timestamperCertificate == null)
{
issues.Add(SignatureLog.Issue(treatIssueAsError, NuGetLogCode.NU3020, Strings.TimestampNoCertificate));
return(false);
}
if (VerificationUtility.IsTimestampValid(this, signature, treatIssueAsError, issues, SigningSpecifications.V1))
{
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture, Strings.TimestampValue, GeneralizedTime.LocalDateTime.ToString()) + Environment.NewLine));
issues.Add(SignatureLog.InformationLog(string.Format(CultureInfo.CurrentCulture,
Strings.VerificationTimestamperCertDisplay,
$"{Environment.NewLine}{CertificateUtility.X509Certificate2ToString(timestamperCertificate, fingerprintAlgorithm)}")));
var certificateExtraStore = SignedCms.Certificates;
using (var chainHolder = new X509ChainHolder())
{
var chain = chainHolder.Chain;
// This flags should only be set for verification scenarios, not signing
chain.ChainPolicy.VerificationFlags = X509VerificationFlags.IgnoreNotTimeValid | X509VerificationFlags.IgnoreCtlNotTimeValid;
CertificateChainUtility.SetCertBuildChainPolicy(chain.ChainPolicy, certificateExtraStore, DateTime.Now, CertificateType.Timestamp);
var chainBuildSucceed = CertificateChainUtility.BuildCertificateChain(chain, timestamperCertificate, out var chainStatusList);
issues.Add(SignatureLog.DetailedLog(CertificateUtility.X509ChainToString(chain, fingerprintAlgorithm)));
if (chainBuildSucceed)
{
return(true);
}
var chainBuildingHasIssues = false;
IEnumerable <string> messages;
var timestampInvalidCertificateFlags = CertificateChainUtility.DefaultObservedStatusFlags |
(X509ChainStatusFlags.Revoked) |
(X509ChainStatusFlags.NotTimeValid) |
(X509ChainStatusFlags.CtlNotTimeValid);
if (CertificateChainUtility.TryGetStatusMessage(chainStatusList, timestampInvalidCertificateFlags, out messages))
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(treatIssueAsError, NuGetLogCode.NU3028, message));
}
chainBuildingHasIssues = true;
}
// For all the special cases, chain status list only has unique elements for each chain status flag present
// therefore if we are checking for one specific chain status we can use the first of the returned list
// if we are combining checks for more than one, then we have to use the whole list.
const X509ChainStatusFlags RevocationStatusFlags = X509ChainStatusFlags.RevocationStatusUnknown | X509ChainStatusFlags.OfflineRevocation;
if (CertificateChainUtility.TryGetStatusMessage(chainStatusList, RevocationStatusFlags, out messages))
{
if (treatIssueAsError)
{
foreach (var message in messages)
{
issues.Add(SignatureLog.Issue(!settings.AllowUnknownRevocation, NuGetLogCode.NU3028, message));
}
}
if (!chainBuildingHasIssues && (settings.AllowIgnoreTimestamp || settings.AllowUnknownRevocation))
{
return(true);
}
chainBuildingHasIssues = true;
}
// Debug log any errors
issues.Add(
SignatureLog.DebugLog(
string.Format(
CultureInfo.CurrentCulture,
Strings.ErrorInvalidCertificateChain,
string.Join(", ", chainStatusList.Select(x => x.Status.ToString())))));
}
}
return(false);
}