public static void TagMustBeCorrect_Custom(AsnEncodingRules ruleSet)
{
byte[] inputData = { 0x87, 2, 0, 0x80 };
byte[] output = new byte[inputData.Length];
AsnReader reader = new AsnReader(inputData, ruleSet);
Asn1Tag wrongTag1 = new Asn1Tag(TagClass.Application, 0);
Asn1Tag wrongTag2 = new Asn1Tag(TagClass.ContextSpecific, 1);
Asn1Tag correctTag = new Asn1Tag(TagClass.ContextSpecific, 7);
AssertExtensions.Throws <ArgumentException>(
"expectedTag",
() => reader.TryReadPrimitiveOctetString(out _, Asn1Tag.Null));
AssertExtensions.Throws <ArgumentException>(
"expectedTag",
() => reader.TryReadOctetString(output, out _, Asn1Tag.Null));
AssertExtensions.Throws <ArgumentException>(
"expectedTag",
() => reader.ReadOctetString(Asn1Tag.Null));
Assert.True(reader.HasData, "HasData after bad universal tag");
Assert.Throws <AsnContentException>(() => reader.TryReadPrimitiveOctetString(out _));
Assert.Throws <AsnContentException>(() => reader.TryReadOctetString(output, out _));
Assert.Throws <AsnContentException>(() => reader.ReadOctetString());
Assert.True(reader.HasData, "HasData after default tag");
Assert.Throws <AsnContentException>(() => reader.TryReadPrimitiveOctetString(out _, wrongTag1));
Assert.Throws <AsnContentException>(() => reader.TryReadOctetString(output, out _, wrongTag1));
Assert.Throws <AsnContentException>(() => reader.ReadOctetString(wrongTag1));
Assert.True(reader.HasData, "HasData after wrong custom class");
Assert.Throws <AsnContentException>(() => reader.TryReadPrimitiveOctetString(out _, wrongTag2));
Assert.Throws <AsnContentException>(() => reader.TryReadOctetString(output, out _, wrongTag2));
Assert.Throws <AsnContentException>(() => reader.ReadOctetString(wrongTag2));
Assert.True(reader.HasData, "HasData after wrong custom tag value");
Assert.True(reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> value, correctTag));
Assert.Equal("0080", value.ByteArrayToHex());
Assert.False(reader.HasData, "HasData after reading value");
reader = new AsnReader(inputData, ruleSet);
Assert.True(reader.TryReadOctetString(output.AsSpan(1), out int written, correctTag));
Assert.Equal("0080", output.AsSpan(1, written).ByteArrayToHex());
Assert.False(reader.HasData, "HasData after reading value");
reader = new AsnReader(inputData, ruleSet);
byte[] output2 = reader.ReadOctetString(correctTag);
Assert.Equal("0080", output2.ByteArrayToHex());
Assert.False(reader.HasData, "HasData after reading value");
}
public static void ExpectedTag_IgnoresConstructed(
AsnEncodingRules ruleSet,
string inputHex,
TagClass tagClass,
int tagValue)
{
byte[] inputData = inputHex.HexToByteArray();
AsnReader reader = new AsnReader(inputData, ruleSet);
Assert.True(
reader.TryReadPrimitiveOctetString(
out ReadOnlyMemory <byte> val1,
new Asn1Tag(tagClass, tagValue, true)));
Assert.False(reader.HasData);
reader = new AsnReader(inputData, ruleSet);
Assert.True(
reader.TryReadPrimitiveOctetString(
out ReadOnlyMemory <byte> val2,
new Asn1Tag(tagClass, tagValue, false)));
Assert.False(reader.HasData);
Assert.Equal(val1.ByteArrayToHex(), val2.ByteArrayToHex());
}
public static void TryReadPrimitiveOctetStringBytes_Success_CER_MaxLength()
{
// CER says that the maximum encoding length for an OctetString primitive
// is 1000.
//
// So we need 04 [1000] { 1000 anythings }
// 1000 => 0x3E8, so the length encoding is 82 03 E8.
// 1000 + 3 + 1 == 1004
byte[] input = new byte[1004];
input[0] = 0x04;
input[1] = 0x82;
input[2] = 0x03;
input[3] = 0xE8;
// Contents
input[4] = 0x02;
input[5] = 0xA0;
input[1002] = 0xA5;
input[1003] = 0xFC;
AsnReader reader = new AsnReader(input, AsnEncodingRules.CER);
bool success = reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> contents);
Assert.True(success, "reader.TryReadOctetStringBytes");
Assert.Equal(1000, contents.Length);
// Check that it is, in fact, the same memory. No copies with this API.
Assert.True(
Unsafe.AreSame(
ref MemoryMarshal.GetReference(contents.Span),
ref input[4]));
}
internal static ReadOnlyMemory <byte> GetContent(
ReadOnlyMemory <byte> wrappedContent,
string contentType)
{
// Read the input.
//
// PKCS7's id-data is written in both PKCS#7 and CMS as an OCTET STRING wrapping
// the arbitrary bytes, so the OCTET STRING must always be present.
//
// For other types, CMS says to always write an OCTET STRING, and to put the properly
// encoded data within it.
// PKCS#7 originally ommitted the OCTET STRING wrapper for this model, so this is the
// dynamic adapter.
//
// See https://tools.ietf.org/html/rfc5652#section-5.2.1
byte[]? rented = null;
int bytesWritten = 0;
try
{
AsnReader reader = new AsnReader(wrappedContent, AsnEncodingRules.BER);
if (reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> inner))
{
return(inner);
}
rented = CryptoPool.Rent(wrappedContent.Length);
if (!reader.TryReadOctetString(rented, out bytesWritten))
{
Debug.Fail($"TryCopyOctetStringBytes failed with an array larger than the encoded value");
throw new CryptographicException();
}
return(rented.AsSpan(0, bytesWritten).ToArray());
}
catch (Exception) when(contentType != Oids.Pkcs7Data)
{
}
catch (AsnContentException e)
{
throw new CryptographicException(SR.Cryptography_Der_Invalid_Encoding, e);
}
finally
{
if (rented != null)
{
CryptoPool.Return(rented, bytesWritten);
}
}
// PKCS#7 encoding for something other than id-data.
Debug.Assert(contentType != Oids.Pkcs7Data);
return(wrappedContent);
}
public static void TagMustBeCorrect_Universal(AsnEncodingRules ruleSet)
{
byte[] inputData = { 4, 1, 0x7E };
AsnReader reader = new AsnReader(inputData, ruleSet);
AssertExtensions.Throws <ArgumentException>(
"expectedTag",
() => reader.TryReadPrimitiveOctetString(out _, Asn1Tag.Null));
Assert.True(reader.HasData, "HasData after bad universal tag");
Assert.Throws <AsnContentException>(
() => reader.TryReadPrimitiveOctetString(out _, new Asn1Tag(TagClass.ContextSpecific, 0)));
Assert.True(reader.HasData, "HasData after wrong tag");
Assert.True(reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> value));
Assert.Equal("7E", value.ByteArrayToHex());
Assert.False(reader.HasData, "HasData after read");
}
public static void TryReadPrimitiveOctetStringBytes_Throws(
string description,
AsnEncodingRules ruleSet,
string inputHex)
{
_ = description;
byte[] inputData = inputHex.HexToByteArray();
AsnReader reader = new AsnReader(inputData, ruleSet);
Assert.Throws <AsnContentException>(
() => reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> contents));
}
public static void TryReadPrimitiveOctetStringBytes_Success(
AsnEncodingRules ruleSet,
int expectedLength,
string inputHex)
{
byte[] inputData = inputHex.HexToByteArray();
AsnReader reader = new AsnReader(inputData, ruleSet);
bool didRead = reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> contents);
Assert.True(didRead, "reader.TryReadOctetStringBytes");
Assert.Equal(expectedLength, contents.Length);
}
private static void AssertExtension(AsnReader extensions, string oid, bool critical, int index, byte[] bytes)
{
AsnReader extension = extensions.ReadSequence();
Assert.Equal(oid, extension.ReadObjectIdentifier());
if (critical)
{
Assert.True(extension.ReadBoolean(), $"{oid} is critical");
}
Assert.True(extension.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> extensionBytes));
AssertRefSame(extensionBytes, ref bytes[index], $"{oid} extension value is at byte {index}");
}
public static void TryReadPrimitiveOctetStringBytes_Fails(
string description,
AsnEncodingRules ruleSet,
string inputHex)
{
_ = description;
byte[] inputData = inputHex.HexToByteArray();
AsnReader reader = new AsnReader(inputData, ruleSet);
bool didRead = reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> contents);
Assert.False(didRead, "reader.TryReadOctetStringBytes");
Assert.Equal(0, contents.Length);
}
public static void TryReadPrimitiveOctetStringBytes_Throws_CER_TooLong()
{
// CER says that the maximum encoding length for an OctetString primitive
// is 1000.
//
// So we need 04 [1001] { 1001 0x00s }
// 1001 => 0x3E9, so the length encoding is 82 03 E9.
// 1001 + 3 + 1 == 1005
byte[] input = new byte[1005];
input[0] = 0x04;
input[1] = 0x82;
input[2] = 0x03;
input[3] = 0xE9;
AsnReader reader = new AsnReader(input, AsnEncodingRules.CER);
Assert.Throws <AsnContentException>(
() => reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> contents));
Assert.Throws <AsnContentException>(
() => reader.TryReadOctetString(new byte[input.Length], out _));
Assert.Throws <AsnContentException>(() => reader.ReadOctetString());
}
public static void ReadMicrosoftComCert()
{
byte[] bytes = MicrosoftDotComSslCertBytes;
AsnReader fileReader = new AsnReader(bytes, AsnEncodingRules.DER);
AsnReader certReader = fileReader.ReadSequence();
Assert.False(fileReader.HasData, "fileReader.HasData");
AsnReader tbsCertReader = certReader.ReadSequence();
AsnReader sigAlgReader = certReader.ReadSequence();
Assert.True(
certReader.TryReadPrimitiveBitString(
out int unusedBitCount,
out ReadOnlyMemory <byte> signature),
"certReader.TryReadPrimitiveBitStringValue");
Assert.Equal(0, unusedBitCount);
AssertRefSame(signature, ref bytes[1176], "Signature is a ref to bytes[1176]");
Assert.False(certReader.HasData, "certReader.HasData");
AsnReader versionExplicitWrapper = tbsCertReader.ReadSequence(new Asn1Tag(TagClass.ContextSpecific, 0));
Assert.True(versionExplicitWrapper.TryReadInt32(out int certVersion));
Assert.Equal(2, certVersion);
Assert.False(versionExplicitWrapper.HasData, "versionExplicitWrapper.HasData");
ReadOnlyMemory <byte> serialBytes = tbsCertReader.ReadIntegerBytes();
AssertRefSame(serialBytes, ref bytes[15], "Serial number starts at bytes[15]");
AsnReader tbsSigAlgReader = tbsCertReader.ReadSequence();
Assert.Equal("1.2.840.113549.1.1.11", tbsSigAlgReader.ReadObjectIdentifier());
Assert.True(tbsSigAlgReader.HasData, "tbsSigAlgReader.HasData before ReadNull");
tbsSigAlgReader.ReadNull();
Assert.False(tbsSigAlgReader.HasData, "tbsSigAlgReader.HasData after ReadNull");
AsnReader issuerReader = tbsCertReader.ReadSequence();
Asn1Tag printableString = new Asn1Tag(UniversalTagNumber.PrintableString);
AssertRdn(issuerReader, "2.5.4.6", 57, printableString, bytes, "issuer[C]");
AssertRdn(issuerReader, "2.5.4.10", 70, printableString, bytes, "issuer[O]");
AssertRdn(issuerReader, "2.5.4.11", 101, printableString, bytes, "issuer[OU]");
AssertRdn(issuerReader, "2.5.4.3", 134, printableString, bytes, "issuer[CN]");
Assert.False(issuerReader.HasData, "issuerReader.HasData");
AsnReader validityReader = tbsCertReader.ReadSequence();
Assert.Equal(new DateTimeOffset(2014, 10, 15, 0, 0, 0, TimeSpan.Zero), validityReader.ReadUtcTime());
Assert.Equal(new DateTimeOffset(2016, 10, 15, 23, 59, 59, TimeSpan.Zero), validityReader.ReadUtcTime());
Assert.False(validityReader.HasData, "validityReader.HasData");
AsnReader subjectReader = tbsCertReader.ReadSequence();
Asn1Tag utf8String = new Asn1Tag(UniversalTagNumber.UTF8String);
AssertRdn(subjectReader, "1.3.6.1.4.1.311.60.2.1.3", 220, printableString, bytes, "subject[EV Country]");
AssertRdn(subjectReader, "1.3.6.1.4.1.311.60.2.1.2", 241, utf8String, bytes, "subject[EV State]", "Washington");
AssertRdn(subjectReader, "2.5.4.15", 262, printableString, bytes, "subject[Business Category]");
AssertRdn(subjectReader, "2.5.4.5", 293, printableString, bytes, "subject[Serial Number]");
AssertRdn(subjectReader, "2.5.4.6", 313, printableString, bytes, "subject[C]");
AssertRdn(subjectReader, "2.5.4.17", 326, utf8String, bytes, "subject[Postal Code]", "98052");
AssertRdn(subjectReader, "2.5.4.8", 342, utf8String, bytes, "subject[ST]", "Washington");
AssertRdn(subjectReader, "2.5.4.7", 363, utf8String, bytes, "subject[L]", "Redmond");
AssertRdn(subjectReader, "2.5.4.9", 381, utf8String, bytes, "subject[Street Address]", "1 Microsoft Way");
AssertRdn(subjectReader, "2.5.4.10", 407, utf8String, bytes, "subject[O]", "Microsoft Corporation");
AssertRdn(subjectReader, "2.5.4.11", 439, utf8String, bytes, "subject[OU]", "MSCOM");
AssertRdn(subjectReader, "2.5.4.3", 455, utf8String, bytes, "subject[CN]", "www.microsoft.com");
Assert.False(subjectReader.HasData, "subjectReader.HasData");
AsnReader subjectPublicKeyInfo = tbsCertReader.ReadSequence();
AsnReader spkiAlgorithm = subjectPublicKeyInfo.ReadSequence();
Assert.Equal("1.2.840.113549.1.1.1", spkiAlgorithm.ReadObjectIdentifier());
spkiAlgorithm.ReadNull();
Assert.False(spkiAlgorithm.HasData, "spkiAlgorithm.HasData");
Assert.True(
subjectPublicKeyInfo.TryReadPrimitiveBitString(
out unusedBitCount,
out ReadOnlyMemory <byte> encodedPublicKey),
"subjectPublicKeyInfo.TryReadBitStringBytes");
Assert.Equal(0, unusedBitCount);
AssertRefSame(encodedPublicKey, ref bytes[498], "Encoded public key starts at byte 498");
Assert.False(subjectPublicKeyInfo.HasData, "subjectPublicKeyInfo.HasData");
AsnReader publicKeyReader = new AsnReader(encodedPublicKey, AsnEncodingRules.DER);
AsnReader rsaPublicKeyReader = publicKeyReader.ReadSequence();
AssertRefSame(rsaPublicKeyReader.ReadIntegerBytes(), ref bytes[506], "RSA Modulus is at bytes[502]");
Assert.True(rsaPublicKeyReader.TryReadInt32(out int rsaExponent));
Assert.Equal(65537, rsaExponent);
Assert.False(rsaPublicKeyReader.HasData, "rsaPublicKeyReader.HasData");
Assert.False(publicKeyReader.HasData, "publicKeyReader.HasData");
AsnReader extensionsContainer = tbsCertReader.ReadSequence(new Asn1Tag(TagClass.ContextSpecific, 3));
AsnReader extensions = extensionsContainer.ReadSequence();
Assert.False(extensionsContainer.HasData, "extensionsContainer.HasData");
AsnReader sanExtension = extensions.ReadSequence();
Assert.Equal("2.5.29.17", sanExtension.ReadObjectIdentifier());
Assert.True(sanExtension.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> sanExtensionBytes));
Assert.False(sanExtension.HasData, "sanExtension.HasData");
AsnReader sanExtensionPayload = new AsnReader(sanExtensionBytes, AsnEncodingRules.DER);
AsnReader sanExtensionValue = sanExtensionPayload.ReadSequence();
Assert.False(sanExtensionPayload.HasData, "sanExtensionPayload.HasData");
Asn1Tag dnsName = new Asn1Tag(TagClass.ContextSpecific, 2);
Assert.Equal("www.microsoft.com", sanExtensionValue.ReadCharacterString(UniversalTagNumber.IA5String, dnsName));
Assert.Equal("wwwqa.microsoft.com", sanExtensionValue.ReadCharacterString(UniversalTagNumber.IA5String, dnsName));
Assert.False(sanExtensionValue.HasData, "sanExtensionValue.HasData");
AsnReader basicConstraints = extensions.ReadSequence();
Assert.Equal("2.5.29.19", basicConstraints.ReadObjectIdentifier());
Assert.True(basicConstraints.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> basicConstraintsBytes));
AsnReader basicConstraintsPayload = new AsnReader(basicConstraintsBytes, AsnEncodingRules.DER);
AsnReader basicConstraintsValue = basicConstraintsPayload.ReadSequence();
Assert.False(basicConstraintsValue.HasData, "basicConstraintsValue.HasData");
Assert.False(basicConstraintsPayload.HasData, "basicConstraintsPayload.HasData");
AsnReader keyUsageExtension = extensions.ReadSequence();
Assert.Equal("2.5.29.15", keyUsageExtension.ReadObjectIdentifier());
Assert.True(keyUsageExtension.ReadBoolean(), "keyUsageExtension.ReadBoolean() (IsCritical)");
Assert.True(keyUsageExtension.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> keyUsageBytes));
AsnReader keyUsagePayload = new AsnReader(keyUsageBytes, AsnEncodingRules.DER);
Assert.Equal(
X509KeyUsageCSharpStyle.DigitalSignature | X509KeyUsageCSharpStyle.KeyEncipherment,
keyUsagePayload.ReadNamedBitListValue <X509KeyUsageCSharpStyle>());
Assert.False(keyUsagePayload.HasData, "keyUsagePayload.HasData");
AssertExtension(extensions, "2.5.29.37", false, 863, bytes);
AssertExtension(extensions, "2.5.29.32", false, 894, bytes);
AssertExtension(extensions, "2.5.29.35", false, 998, bytes);
AssertExtension(extensions, "2.5.29.31", false, 1031, bytes);
AssertExtension(extensions, "1.3.6.1.5.5.7.1.1", false, 1081, bytes);
Assert.False(extensions.HasData, "extensions.HasData");
Assert.Equal("1.2.840.113549.1.1.11", sigAlgReader.ReadObjectIdentifier());
sigAlgReader.ReadNull();
Assert.False(sigAlgReader.HasData);
}
internal static AlgorithmIdentifier ToPresentationObject(this AlgorithmIdentifierAsn asn)
{
int keyLength;
byte[] parameters = Array.Empty <byte>();
switch (asn.Algorithm)
{
case Oids.Rc2Cbc:
{
if (asn.Parameters == null)
{
keyLength = 0;
break;
}
Rc2CbcParameters rc2Params = Rc2CbcParameters.Decode(
asn.Parameters.Value,
AsnEncodingRules.BER);
int keySize = rc2Params.GetEffectiveKeyBits();
// These are the only values .NET Framework would set.
switch (keySize)
{
case 40:
case 56:
case 64:
case 128:
keyLength = keySize;
break;
default:
keyLength = 0;
break;
}
break;
}
case Oids.Rc4:
{
if (asn.Parameters == null)
{
keyLength = 0;
break;
}
int saltLen = 0;
try
{
AsnReader reader = new AsnReader(asn.Parameters.Value, AsnEncodingRules.BER);
// DER NULL is considered the same as not present.
// No call to ReadNull() is necessary because the serializer already verified that
// there's no data after the [AnyValue] value.
if (reader.PeekTag() != Asn1Tag.Null)
{
if (reader.TryReadPrimitiveOctetString(out ReadOnlyMemory <byte> contents))
{
saltLen = contents.Length;
}
else
{
Span <byte> salt = stackalloc byte[KeyLengths.Rc4Max_128Bit / 8];
if (!reader.TryReadOctetString(salt, out saltLen))
{
throw new CryptographicException();
}
}
}
}
catch (AsnContentException e)
{
throw new CryptographicException(SR.Cryptography_Der_Invalid_Encoding, e);
}
keyLength = KeyLengths.Rc4Max_128Bit - 8 * saltLen;
break;
}
case Oids.DesCbc:
keyLength = KeyLengths.Des_64Bit;
break;
case Oids.TripleDesCbc:
keyLength = KeyLengths.TripleDes_192Bit;
break;
case Oids.RsaOaep when !asn.HasNullEquivalentParameters():
keyLength = 0;
Debug.Assert(asn.Parameters != null);
parameters = asn.Parameters.Value.ToArray();
break;
default:
// .NET Framework doesn't set a keylength for AES, or any other algorithm than the ones
// listed here.
keyLength = 0;
break;
}
return(new AlgorithmIdentifier(new Oid(asn.Algorithm), keyLength)
{
Parameters = parameters
});
}