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Rob-HagueRob-Hague
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Abstract out the hash algorithm from RsaDigitalSignature
1 parent 9593e87 commit fc64a52

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4 files changed

+185
-16
lines changed

4 files changed

+185
-16
lines changed

‎src/Renci.SshNet.Tests/Classes/Security/Cryptography/RsaDigitalSignatureTest.cs

Lines changed: 154 additions & 10 deletions
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,9 @@
1-
using Microsoft.VisualStudio.TestTools.UnitTesting;
1+
using System;
2+
using System.Security.Cryptography;
3+
using System.Text;
4+
5+
using Microsoft.VisualStudio.TestTools.UnitTesting;
6+
27
using Renci.SshNet.Security;
38
using Renci.SshNet.Security.Cryptography;
49
using Renci.SshNet.Tests.Common;
@@ -11,17 +16,156 @@ namespace Renci.SshNet.Tests.Classes.Security.Cryptography
1116
[TestClass]
1217
public class RsaDigitalSignatureTest : TestBase
1318
{
19+
[TestMethod]
20+
public void Sha1_SignAndVerify()
21+
{
22+
byte[] data = Encoding.UTF8.GetBytes("hello world");
23+
24+
RsaKey rsaKey = GetRsaKey();
25+
26+
var digitalSignature = new RsaDigitalSignature(rsaKey); // Verify SHA-1 is the default
27+
28+
byte[] signedBytes = digitalSignature.Sign(data);
29+
30+
byte[] expectedSignedBytes = new byte[]
31+
{
32+
// echo -n 'hello world' | openssl dgst -sha1 -sign Key.RSA.txt -out test.signed
33+
0x41, 0x50, 0x12, 0x14, 0xd3, 0x7c, 0xe0, 0x40, 0x50, 0x65, 0xfb, 0x33, 0xd9, 0x17, 0x89, 0xbf,
34+
0xb2, 0x4b, 0x85, 0x15, 0xbf, 0x9e, 0x57, 0x3b, 0x01, 0x15, 0x2b, 0x99, 0xfa, 0x62, 0x9b, 0x2a,
35+
0x05, 0xa0, 0x73, 0xc7, 0xb7, 0x5b, 0xd9, 0x01, 0xaa, 0x56, 0x73, 0x95, 0x13, 0x41, 0x33, 0x0d,
36+
0x7f, 0x83, 0x8a, 0x60, 0x4d, 0x19, 0xdc, 0x9b, 0xba, 0x8e, 0x61, 0xed, 0xd0, 0x8a, 0x3e, 0x38,
37+
0x71, 0xee, 0x34, 0xc3, 0x55, 0x0f, 0x55, 0x65, 0x89, 0xbb, 0x3e, 0x41, 0xee, 0xdf, 0xf5, 0x2f,
38+
0xab, 0x9e, 0x89, 0x37, 0x68, 0x1f, 0x9f, 0x38, 0x00, 0x81, 0x29, 0x93, 0xeb, 0x61, 0x37, 0xad,
39+
0x8d, 0x35, 0xf1, 0x3d, 0x4b, 0x9b, 0x99, 0x74, 0x7b, 0xeb, 0xf4, 0xfb, 0x76, 0xb4, 0xb6, 0xb4,
40+
0x09, 0x33, 0x5c, 0xfa, 0x6a, 0xad, 0x1e, 0xed, 0x1c, 0xe1, 0xb4, 0x4d, 0xf2, 0xa5, 0xc3, 0x64,
41+
0x9a, 0x45, 0x81, 0xee, 0x1b, 0xa6, 0x1d, 0x01, 0x3c, 0x4d, 0xb5, 0x62, 0x9e, 0xff, 0x8e, 0xff,
42+
0x6c, 0x18, 0xed, 0xe9, 0x8e, 0x03, 0x2c, 0xc5, 0x94, 0x81, 0xca, 0x8b, 0x18, 0x3f, 0x25, 0xcd,
43+
0xe5, 0x42, 0x49, 0x43, 0x23, 0x1f, 0xdc, 0x3f, 0xa2, 0x43, 0xbc, 0xbd, 0x42, 0xf5, 0x60, 0xfb,
44+
0x01, 0xd3, 0x67, 0x0d, 0x8d, 0x85, 0x7b, 0x51, 0x14, 0xec, 0x26, 0x53, 0x00, 0x61, 0x25, 0x16,
45+
0x19, 0x10, 0x3c, 0x86, 0x16, 0x59, 0x84, 0x08, 0xd1, 0xf9, 0x1e, 0x05, 0x88, 0xbd, 0x4a, 0x01,
46+
0x43, 0x4e, 0xec, 0x76, 0x0b, 0xd7, 0x2c, 0xe9, 0x98, 0xb1, 0x4c, 0x0a, 0x13, 0xc6, 0x95, 0xf9,
47+
0x8f, 0x95, 0x5c, 0x98, 0x4c, 0x8f, 0x97, 0x4a, 0xad, 0x0d, 0xfe, 0x84, 0xf0, 0x56, 0xc3, 0x29,
48+
0x73, 0x75, 0x55, 0x3c, 0xd9, 0x5e, 0x5b, 0x6f, 0xf9, 0x81, 0xbc, 0xbc, 0x50, 0x75, 0x7d, 0xa8
49+
};
50+
51+
CollectionAssert.AreEqual(expectedSignedBytes, signedBytes);
52+
53+
// Also verify RsaKey uses SHA-1 by default
54+
CollectionAssert.AreEqual(expectedSignedBytes, rsaKey.Sign(data));
55+
56+
// The following fails due to the _isPrivate decision in RsaCipher.Transform. Is that really correct?
57+
//Assert.IsTrue(digitalSignature.Verify(data, signedBytes));
58+
59+
// 'Workaround': use a key with no private key information
60+
var digitalSignaturePublic = new RsaDigitalSignature(new RsaKey()
61+
{
62+
Public = rsaKey.Public
63+
});
64+
Assert.IsTrue(digitalSignaturePublic.Verify(data, signedBytes));
65+
}
1466

15-
/// <summary>
16-
///A test for RsaDigitalSignature Constructor
17-
///</summary>
1867
[TestMethod]
19-
[Ignore] // placeholder for actual test
20-
public void RsaDigitalSignatureConstructorTest()
68+
public void Sha256_SignAndVerify()
2169
{
22-
RsaKey rsaKey = null; // TODO: Initialize to an appropriate value
23-
RsaDigitalSignature target = new RsaDigitalSignature(rsaKey);
24-
Assert.Inconclusive("TODO: Implement code to verify target");
70+
byte[] data = Encoding.UTF8.GetBytes("hello world");
71+
72+
RsaKey rsaKey = GetRsaKey();
73+
74+
var digitalSignature = new RsaDigitalSignature(rsaKey, HashAlgorithmName.SHA256);
75+
76+
byte[] signedBytes = digitalSignature.Sign(data);
77+
78+
CollectionAssert.AreEqual(new byte[]
79+
{
80+
// echo -n 'hello world' | openssl dgst -sha256 -sign Key.RSA.txt -out test.signed
81+
0x2e, 0xef, 0x01, 0x49, 0x5c, 0x66, 0x37, 0x56, 0xc2, 0xfb, 0x7b, 0xfa, 0x80, 0x2f, 0xdb, 0xaa,
82+
0x0d, 0x15, 0xd9, 0x8d, 0xa9, 0xad, 0x81, 0x4f, 0x09, 0x2e, 0x53, 0x9e, 0xce, 0x5d, 0x68, 0x07,
83+
0xae, 0xb9, 0xc0, 0x45, 0xfa, 0x30, 0xd0, 0xf7, 0xd6, 0xa6, 0x8d, 0x19, 0x24, 0x3a, 0xea, 0x91,
84+
0x3e, 0xa2, 0x4a, 0x42, 0x2e, 0x21, 0xf1, 0x48, 0x57, 0xca, 0x2b, 0x6c, 0x9f, 0x79, 0x54, 0x91,
85+
0x3e, 0x3a, 0x4d, 0xd1, 0x70, 0x87, 0x3d, 0xbe, 0x22, 0x97, 0xc9, 0xb0, 0x02, 0xf0, 0xa2, 0xae,
86+
0x7a, 0xbb, 0x8b, 0xaf, 0xc0, 0x3b, 0xab, 0x71, 0xe8, 0x29, 0x1c, 0x18, 0x88, 0xca, 0x74, 0x1b,
87+
0x34, 0x4f, 0xd1, 0x83, 0x39, 0x6e, 0x8f, 0x69, 0x3d, 0x7e, 0xef, 0xef, 0x57, 0x7c, 0xff, 0x21,
88+
0x9c, 0x10, 0x2b, 0xd1, 0x4f, 0x26, 0xbe, 0xaa, 0xd2, 0xd9, 0x03, 0x14, 0x75, 0x97, 0x11, 0xaf,
89+
0xf0, 0x28, 0xf2, 0xd3, 0x07, 0x79, 0x5b, 0x27, 0xdc, 0x97, 0xd8, 0xce, 0x4e, 0x78, 0x89, 0x16,
90+
0x91, 0x2a, 0xb2, 0x47, 0x53, 0x94, 0xe9, 0xa1, 0x15, 0x98, 0x29, 0x0c, 0xa1, 0xf5, 0xe2, 0x8e,
91+
0x11, 0xdc, 0x0c, 0x1c, 0x10, 0xa4, 0xf2, 0x46, 0x5c, 0x78, 0x0c, 0xc1, 0x4a, 0x65, 0x21, 0x8a,
92+
0x2e, 0x32, 0x6c, 0x72, 0x06, 0xf9, 0x7f, 0xa1, 0x6c, 0x2e, 0x13, 0x06, 0x41, 0xaa, 0x23, 0xdd,
93+
0xc8, 0x1c, 0x61, 0xb6, 0x96, 0x87, 0xc4, 0x84, 0xc8, 0x61, 0xec, 0x4e, 0xdd, 0x49, 0x9e, 0x4f,
94+
0x0d, 0x8c, 0xf1, 0x7f, 0xf2, 0x6c, 0x73, 0x5a, 0xa6, 0x3b, 0xbf, 0x4e, 0xba, 0x57, 0x6b, 0xb3,
95+
0x1e, 0x6c, 0x57, 0x76, 0x87, 0x9f, 0xb4, 0x3b, 0xcb, 0xcd, 0xe5, 0x10, 0x7a, 0x4c, 0xeb, 0xc0,
96+
0xc4, 0xc3, 0x75, 0x51, 0x5f, 0xb7, 0x7c, 0xbc, 0x55, 0x8d, 0x05, 0xc7, 0xed, 0xc7, 0x52, 0x4a
97+
}, signedBytes);
98+
99+
100+
// The following fails due to the _isPrivate decision in RsaCipher.Transform. Is that really correct?
101+
//Assert.IsTrue(digitalSignature.Verify(data, signedBytes));
102+
103+
// 'Workaround': use a key with no private key information
104+
var digitalSignaturePublic = new RsaDigitalSignature(new RsaKey()
105+
{
106+
Public = rsaKey.Public
107+
}, HashAlgorithmName.SHA256);
108+
Assert.IsTrue(digitalSignaturePublic.Verify(data, signedBytes));
109+
}
110+
111+
[TestMethod]
112+
public void Sha512_SignAndVerify()
113+
{
114+
byte[] data = Encoding.UTF8.GetBytes("hello world");
115+
116+
RsaKey rsaKey = GetRsaKey();
117+
118+
var digitalSignature = new RsaDigitalSignature(rsaKey, HashAlgorithmName.SHA512);
119+
120+
byte[] signedBytes = digitalSignature.Sign(data);
121+
122+
CollectionAssert.AreEqual(new byte[]
123+
{
124+
// echo -n 'hello world' | openssl dgst -sha512 -sign Key.RSA.txt -out test.signed
125+
0x69, 0x70, 0xb5, 0x9f, 0x32, 0x86, 0x3b, 0xae, 0xc0, 0x79, 0x6e, 0xdb, 0x35, 0xd5, 0xa6, 0x22,
126+
0xcd, 0x2b, 0x4b, 0xd2, 0x68, 0x1a, 0x65, 0x41, 0xa6, 0xd9, 0x20, 0x54, 0x31, 0x9a, 0xb1, 0x44,
127+
0x6e, 0x8f, 0x56, 0x4b, 0xfc, 0x27, 0x7f, 0x3f, 0xe7, 0x47, 0xcb, 0x78, 0x03, 0x05, 0x79, 0x8a,
128+
0x16, 0x7b, 0x12, 0x01, 0x3a, 0xa2, 0xd5, 0x0d, 0x2b, 0x16, 0x38, 0xef, 0x84, 0x6b, 0xd7, 0x19,
129+
0xeb, 0xac, 0x54, 0x01, 0x9d, 0xa6, 0x80, 0x74, 0x43, 0xa8, 0x6e, 0x5e, 0x33, 0x05, 0x06, 0x1d,
130+
0x6d, 0xfe, 0x32, 0x4f, 0xe3, 0xcb, 0x3e, 0x2d, 0x4e, 0xe1, 0x47, 0x03, 0x69, 0xb4, 0x59, 0x80,
131+
0x59, 0x05, 0x15, 0xa0, 0x11, 0x34, 0x47, 0x58, 0xd7, 0x93, 0x2d, 0x40, 0xf2, 0x2c, 0x37, 0x48,
132+
0x6b, 0x3c, 0xd3, 0x03, 0x09, 0x32, 0x74, 0xa0, 0x2d, 0x33, 0x11, 0x99, 0x10, 0xb4, 0x09, 0x31,
133+
0xec, 0xa3, 0x2c, 0x63, 0xba, 0x50, 0xd1, 0x02, 0x45, 0xae, 0xb5, 0x75, 0x7e, 0xfa, 0xfc, 0x06,
134+
0xb6, 0x6a, 0xb2, 0xa1, 0x73, 0x14, 0xa5, 0xaa, 0x17, 0x88, 0x03, 0x19, 0x14, 0x9b, 0xe1, 0x10,
135+
0xf8, 0x2f, 0x73, 0x01, 0xc7, 0x8d, 0x37, 0xef, 0x98, 0x69, 0xc2, 0xe2, 0x7a, 0x11, 0xd5, 0xb8,
136+
0xc9, 0x35, 0x45, 0xcb, 0x56, 0x4b, 0x92, 0x4a, 0xe0, 0x4c, 0xd6, 0x82, 0xae, 0xad, 0x5b, 0xe9,
137+
0x40, 0x7e, 0x2a, 0x48, 0x7d, 0x57, 0xc5, 0xfd, 0xe9, 0x98, 0xe0, 0xbb, 0x09, 0xa1, 0xf5, 0x48,
138+
0x45, 0xcb, 0xee, 0xb9, 0x99, 0x81, 0x44, 0x15, 0x2e, 0x50, 0x39, 0x64, 0x58, 0x4c, 0x34, 0x86,
139+
0xf8, 0x81, 0x9e, 0x1d, 0xb6, 0x97, 0xe0, 0xce, 0x16, 0xca, 0x20, 0x46, 0xe9, 0x49, 0x8f, 0xe6,
140+
0xa0, 0x23, 0x08, 0x80, 0xa6, 0x37, 0x70, 0x06, 0xcc, 0x8f, 0xf4, 0xa0, 0x74, 0x53, 0x26, 0x38
141+
}, signedBytes);
142+
143+
// The following fails due to the _isPrivate decision in RsaCipher.Transform. Is that really correct?
144+
//Assert.IsTrue(digitalSignature.Verify(data, signedBytes));
145+
146+
// 'Workaround': use a key with no private key information
147+
var digitalSignaturePublic = new RsaDigitalSignature(new RsaKey()
148+
{
149+
Public = rsaKey.Public
150+
}, HashAlgorithmName.SHA512);
151+
Assert.IsTrue(digitalSignaturePublic.Verify(data, signedBytes));
152+
}
153+
154+
[TestMethod]
155+
public void Constructor_InvalidHashAlgorithm_ThrowsArgumentException()
156+
{
157+
ArgumentException exception = Assert.ThrowsException<ArgumentException>(
158+
() => new RsaDigitalSignature(new RsaKey(), new HashAlgorithmName("invalid")));
159+
160+
Assert.AreEqual("hashAlgorithmName", exception.ParamName);
161+
}
162+
163+
private static RsaKey GetRsaKey()
164+
{
165+
using (var stream = GetData("Key.RSA.txt"))
166+
{
167+
return (RsaKey) ((KeyHostAlgorithm) new PrivateKeyFile(stream).HostKey).Key;
168+
}
25169
}
26170

27171
/// <summary>
@@ -37,4 +181,4 @@ public void DisposeTest()
37181
Assert.Inconclusive("A method that does not return a value cannot be verified.");
38182
}
39183
}
40-
}
184+
}

‎src/Renci.SshNet.Tests/Common/TestBase.cs

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -49,9 +49,9 @@ protected void CreateTestFile(string fileName, int size)
4949
}
5050
}
5151

52-
protected Stream GetData(string name)
52+
protected static Stream GetData(string name)
5353
{
5454
return ExecutingAssembly.GetManifestResourceStream(string.Format("Renci.SshNet.Tests.Data.{0}", name));
5555
}
5656
}
57-
}
57+
}

‎src/Renci.SshNet/Common/ObjectIdentifier.cs

Lines changed: 16 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,6 @@
11
using System;
2+
using System.Linq;
3+
using System.Security.Cryptography;
24

35
namespace Renci.SshNet.Common
46
{
@@ -32,5 +34,19 @@ public ObjectIdentifier(params ulong[] identifiers)
3234

3335
Identifiers = identifiers;
3436
}
37+
38+
internal static ObjectIdentifier FromHashAlgorithmName(HashAlgorithmName hashAlgorithmName)
39+
{
40+
var oid = CryptoConfig.MapNameToOID(hashAlgorithmName.Name);
41+
42+
if (oid is null)
43+
{
44+
throw new ArgumentException($"Could not map `{hashAlgorithmName}` to OID.", nameof(hashAlgorithmName));
45+
}
46+
47+
var identifiers = oid.Split('.').Select(ulong.Parse).ToArray();
48+
49+
return new ObjectIdentifier(identifiers);
50+
}
3551
}
3652
}

‎src/Renci.SshNet/Security/Cryptography/RsaDigitalSignature.cs

Lines changed: 13 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -1,6 +1,5 @@
11
using System;
22
using System.Security.Cryptography;
3-
using Renci.SshNet.Abstractions;
43
using Renci.SshNet.Common;
54
using Renci.SshNet.Security.Cryptography.Ciphers;
65

@@ -14,13 +13,23 @@ public class RsaDigitalSignature : CipherDigitalSignature, IDisposable
1413
private HashAlgorithm _hash;
1514

1615
/// <summary>
17-
/// Initializes a new instance of the <see cref="RsaDigitalSignature"/> class.
16+
/// Initializes a new instance of the <see cref="RsaDigitalSignature"/> class with the SHA1 hash algorithm.
1817
/// </summary>
1918
/// <param name="rsaKey">The RSA key.</param>
2019
public RsaDigitalSignature(RsaKey rsaKey)
21-
: base(new ObjectIdentifier(1, 3, 14, 3, 2, 26), new RsaCipher(rsaKey))
20+
: this(rsaKey, HashAlgorithmName.SHA1)
21+
{ }
22+
23+
/// <summary>
24+
/// Initializes a new instance of the <see cref="RsaDigitalSignature"/> class.
25+
/// </summary>
26+
/// <param name="rsaKey">The RSA key.</param>
27+
/// <param name="hashAlgorithmName">The hash algorithm to use in the digital signature.</param>
28+
public RsaDigitalSignature(RsaKey rsaKey, HashAlgorithmName hashAlgorithmName)
29+
: base(ObjectIdentifier.FromHashAlgorithmName(hashAlgorithmName), new RsaCipher(rsaKey))
2230
{
23-
_hash = CryptoAbstraction.CreateSHA1();
31+
_hash = CryptoConfig.CreateFromName(hashAlgorithmName.Name) as HashAlgorithm
32+
?? throw new ArgumentException($"Could not create {nameof(HashAlgorithm)} from `{hashAlgorithmName}`.", nameof(hashAlgorithmName));
2433
}
2534

2635
/// <summary>

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