2 // X509Certificates.cs: Handles X.509 certificates.
5 // Sebastien Pouliot <sebastien@ximian.com>
7 // (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
8 // Copyright (C) 2004-2006 Novell, Inc (http://www.novell.com)
10 // Permission is hereby granted, free of charge, to any person obtaining
11 // a copy of this software and associated documentation files (the
12 // "Software"), to deal in the Software without restriction, including
13 // without limitation the rights to use, copy, modify, merge, publish,
14 // distribute, sublicense, and/or sell copies of the Software, and to
15 // permit persons to whom the Software is furnished to do so, subject to
16 // the following conditions:
18 // The above copyright notice and this permission notice shall be
19 // included in all copies or substantial portions of the Software.
21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
31 using System.Runtime.Serialization;
32 using System.Security.Cryptography;
33 using SSCX = System.Security.Cryptography.X509Certificates;
34 using System.Security.Permissions;
37 namespace Mono.Security.X509 {
40 // a. Internet X.509 Public Key Infrastructure Certificate and CRL Profile
41 // http://www.ietf.org/rfc/rfc3280.txt
42 // b. ITU ASN.1 standards (free download)
43 // http://www.itu.int/ITU-T/studygroups/com17/languages/
46 internal class X509Certificate : ISerializable {
48 public class X509Certificate : ISerializable {
50 public class X509Certificate {
55 private byte[] m_encodedcert;
56 private DateTime m_from;
57 private DateTime m_until;
59 private string m_issuername;
60 private string m_keyalgo;
61 private byte[] m_keyalgoparams;
63 private string m_subject;
64 private byte[] m_publickey;
65 private byte[] signature;
66 private string m_signaturealgo;
67 private byte[] m_signaturealgoparams;
68 private byte[] certhash;
72 // from http://www.ietf.org/rfc/rfc2459.txt
74 //Certificate ::= SEQUENCE {
75 // tbsCertificate TBSCertificate,
76 // signatureAlgorithm AlgorithmIdentifier,
77 // signature BIT STRING }
79 //TBSCertificate ::= SEQUENCE {
80 // version [0] Version DEFAULT v1,
81 // serialNumber CertificateSerialNumber,
82 // signature AlgorithmIdentifier,
86 // subjectPublicKeyInfo SubjectPublicKeyInfo,
87 // issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
88 // -- If present, version shall be v2 or v3
89 // subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
90 // -- If present, version shall be v2 or v3
91 // extensions [3] Extensions OPTIONAL
92 // -- If present, version shall be v3 -- }
94 private byte[] serialnumber;
96 // private byte[] issuerUniqueID;
97 // private byte[] subjectUniqueID;
98 private X509ExtensionCollection extensions;
100 private static string encoding_error = Locale.GetText ("Input data cannot be coded as a valid certificate.");
103 // that's were the real job is!
104 private void Parse (byte[] data)
107 decoder = new ASN1 (data);
109 if (decoder.Tag != 0x30)
110 throw new CryptographicException (encoding_error);
111 // Certificate / TBSCertificate
112 if (decoder [0].Tag != 0x30)
113 throw new CryptographicException (encoding_error);
115 ASN1 tbsCertificate = decoder [0];
118 // Certificate / TBSCertificate / Version
119 ASN1 v = decoder [0][tbs];
120 version = 1; // DEFAULT v1
121 if ((v.Tag == 0xA0) && (v.Count > 0)) {
122 // version (optional) is present only in v2+ certs
123 version += v [0].Value [0]; // zero based
127 // Certificate / TBSCertificate / CertificateSerialNumber
128 ASN1 sn = decoder [0][tbs++];
130 throw new CryptographicException (encoding_error);
131 serialnumber = sn.Value;
132 Array.Reverse (serialnumber, 0, serialnumber.Length);
134 // Certificate / TBSCertificate / AlgorithmIdentifier
136 // ASN1 signatureAlgo = tbsCertificate.Element (tbs++, 0x30);
138 issuer = tbsCertificate.Element (tbs++, 0x30);
139 m_issuername = X501.ToString (issuer);
141 ASN1 validity = tbsCertificate.Element (tbs++, 0x30);
142 ASN1 notBefore = validity [0];
143 m_from = ASN1Convert.ToDateTime (notBefore);
144 ASN1 notAfter = validity [1];
145 m_until = ASN1Convert.ToDateTime (notAfter);
147 subject = tbsCertificate.Element (tbs++, 0x30);
148 m_subject = X501.ToString (subject);
150 ASN1 subjectPublicKeyInfo = tbsCertificate.Element (tbs++, 0x30);
152 ASN1 algorithm = subjectPublicKeyInfo.Element (0, 0x30);
153 ASN1 algo = algorithm.Element (0, 0x06);
154 m_keyalgo = ASN1Convert.ToOid (algo);
155 // parameters ANY DEFINED BY algorithm OPTIONAL
156 // so we dont ask for a specific (Element) type and return DER
157 ASN1 parameters = algorithm [1];
158 m_keyalgoparams = ((algorithm.Count > 1) ? parameters.GetBytes () : null);
160 ASN1 subjectPublicKey = subjectPublicKeyInfo.Element (1, 0x03);
161 // we must drop th first byte (which is the number of unused bits
163 int n = subjectPublicKey.Length - 1;
164 m_publickey = new byte [n];
165 Buffer.BlockCopy (subjectPublicKey.Value, 1, m_publickey, 0, n);
167 // signature processing
168 byte[] bitstring = decoder [2].Value;
169 // first byte contains unused bits in first byte
170 signature = new byte [bitstring.Length - 1];
171 Buffer.BlockCopy (bitstring, 1, signature, 0, signature.Length);
173 algorithm = decoder [1];
174 algo = algorithm.Element (0, 0x06);
175 m_signaturealgo = ASN1Convert.ToOid (algo);
176 parameters = algorithm [1];
177 if (parameters != null)
178 m_signaturealgoparams = parameters.GetBytes ();
180 m_signaturealgoparams = null;
182 // Certificate / TBSCertificate / issuerUniqueID
183 ASN1 issuerUID = tbsCertificate.Element (tbs, 0xA1);
184 if (issuerUID != null) {
186 // issuerUniqueID = issuerUID.Value;
189 // Certificate / TBSCertificate / subjectUniqueID
190 ASN1 subjectUID = tbsCertificate.Element (tbs, 0xA2);
191 if (subjectUID != null) {
193 // subjectUniqueID = subjectUID.Value;
196 // Certificate / TBSCertificate / Extensions
197 ASN1 extns = tbsCertificate.Element (tbs, 0xA3);
198 if ((extns != null) && (extns.Count == 1))
199 extensions = new X509ExtensionCollection (extns [0]);
201 extensions = new X509ExtensionCollection (null);
203 // keep a copy of the original data
204 m_encodedcert = (byte[]) data.Clone ();
206 catch (Exception ex) {
207 throw new CryptographicException (encoding_error, ex);
213 public X509Certificate (byte[] data)
216 // does it looks like PEM ?
217 if ((data.Length > 0) && (data [0] == 0x2D)) {
219 data = PEM ("CERTIFICATE", data);
221 catch (Exception ex) {
222 throw new CryptographicException (encoding_error, ex);
229 private byte[] GetUnsignedBigInteger (byte[] integer)
231 if (integer [0] == 0x00) {
232 // this first byte is added so we're sure it's an unsigned integer
233 // however we can't feed it into RSAParameters or DSAParameters
234 int length = integer.Length - 1;
235 byte[] uinteger = new byte [length];
236 Buffer.BlockCopy (integer, 1, uinteger, 0, length);
248 DSAParameters dsaParams = new DSAParameters ();
249 // for DSA m_publickey contains 1 ASN.1 integer - Y
250 ASN1 pubkey = new ASN1 (m_publickey);
251 if ((pubkey == null) || (pubkey.Tag != 0x02))
253 dsaParams.Y = GetUnsignedBigInteger (pubkey.Value);
255 ASN1 param = new ASN1 (m_keyalgoparams);
256 if ((param == null) || (param.Tag != 0x30) || (param.Count < 3))
258 if ((param [0].Tag != 0x02) || (param [1].Tag != 0x02) || (param [2].Tag != 0x02))
260 dsaParams.P = GetUnsignedBigInteger (param [0].Value);
261 dsaParams.Q = GetUnsignedBigInteger (param [1].Value);
262 dsaParams.G = GetUnsignedBigInteger (param [2].Value);
264 // BUG: MS BCL 1.0 can't import a key which
265 // isn't the same size as the one present in
267 _dsa = (DSA) new DSACryptoServiceProvider (dsaParams.Y.Length << 3);
268 _dsa.ImportParameters (dsaParams);
281 public X509ExtensionCollection Extensions {
282 get { return extensions; }
287 if (certhash == null) {
288 HashAlgorithm hash = null;
289 switch (m_signaturealgo) {
290 case "1.2.840.113549.1.1.2": // MD2 with RSA encryption
291 // maybe someone installed MD2 ?
293 hash = HashAlgorithm.Create ("MD2");
295 hash = Mono.Security.Cryptography.MD2.Create ();
298 case "1.2.840.113549.1.1.4": // MD5 with RSA encryption
299 hash = MD5.Create ();
301 case "1.2.840.113549.1.1.5": // SHA-1 with RSA Encryption
302 case "1.3.14.3.2.29": // SHA1 with RSA signature
303 case "1.2.840.10040.4.3": // SHA1-1 with DSA
304 hash = SHA1.Create ();
309 if ((decoder == null) || (decoder.Count < 1))
311 byte[] toBeSigned = decoder [0].GetBytes ();
312 certhash = hash.ComputeHash (toBeSigned, 0, toBeSigned.Length);
314 return (byte[]) certhash.Clone ();
318 public virtual string IssuerName {
319 get { return m_issuername; }
322 public virtual string KeyAlgorithm {
323 get { return m_keyalgo; }
326 public virtual byte[] KeyAlgorithmParameters {
328 if (m_keyalgoparams == null)
330 return (byte[]) m_keyalgoparams.Clone ();
334 public virtual byte[] PublicKey {
336 if (m_publickey == null)
338 return (byte[]) m_publickey.Clone ();
342 public virtual RSA RSA {
345 RSAParameters rsaParams = new RSAParameters ();
346 // for RSA m_publickey contains 2 ASN.1 integers
347 // the modulus and the public exponent
348 ASN1 pubkey = new ASN1 (m_publickey);
349 ASN1 modulus = pubkey [0];
350 if ((modulus == null) || (modulus.Tag != 0x02))
352 ASN1 exponent = pubkey [1];
353 if (exponent.Tag != 0x02)
356 rsaParams.Modulus = GetUnsignedBigInteger (modulus.Value);
357 rsaParams.Exponent = exponent.Value;
359 // BUG: MS BCL 1.0 can't import a key which
360 // isn't the same size as the one present in
362 int keySize = (rsaParams.Modulus.Length << 3);
363 _rsa = (RSA) new RSACryptoServiceProvider (keySize);
364 _rsa.ImportParameters (rsaParams);
377 public virtual byte[] RawData {
379 if (m_encodedcert == null)
381 return (byte[]) m_encodedcert.Clone ();
385 public virtual byte[] SerialNumber {
387 if (serialnumber == null)
389 return (byte[]) serialnumber.Clone ();
393 public virtual byte[] Signature {
395 if (signature == null)
398 switch (m_signaturealgo) {
399 case "1.2.840.113549.1.1.2": // MD2 with RSA encryption
400 case "1.2.840.113549.1.1.4": // MD5 with RSA encryption
401 case "1.2.840.113549.1.1.5": // SHA-1 with RSA Encryption
402 case "1.3.14.3.2.29": // SHA1 with RSA signature
403 return (byte[]) signature.Clone ();
405 case "1.2.840.10040.4.3": // SHA-1 with DSA
406 ASN1 sign = new ASN1 (signature);
407 if ((sign == null) || (sign.Count != 2))
409 // parts may be less than 20 bytes (i.e. first bytes were 0x00)
410 byte[] part1 = sign [0].Value;
411 byte[] part2 = sign [1].Value;
412 byte[] sig = new byte [40];
413 Buffer.BlockCopy (part1, 0, sig, (20 - part1.Length), part1.Length);
414 Buffer.BlockCopy (part2, 0, sig, (40 - part2.Length), part2.Length);
418 throw new CryptographicException ("Unsupported hash algorithm: " + m_signaturealgo);
423 public virtual string SignatureAlgorithm {
424 get { return m_signaturealgo; }
427 public virtual byte[] SignatureAlgorithmParameters {
429 if (m_signaturealgoparams == null)
430 return m_signaturealgoparams;
431 return (byte[]) m_signaturealgoparams.Clone ();
435 public virtual string SubjectName {
436 get { return m_subject; }
439 public virtual DateTime ValidFrom {
440 get { return m_from; }
443 public virtual DateTime ValidUntil {
444 get { return m_until; }
448 get { return version; }
451 public bool IsCurrent {
452 get { return WasCurrent (DateTime.Now); }
455 public bool WasCurrent (DateTime instant)
457 return ((instant > ValidFrom) && (instant <= ValidUntil));
460 internal bool VerifySignature (DSA dsa)
462 // signatureOID is check by both this.Hash and this.Signature
463 DSASignatureDeformatter v = new DSASignatureDeformatter (dsa);
464 // only SHA-1 is supported
465 v.SetHashAlgorithm ("SHA1");
466 return v.VerifySignature (this.Hash, this.Signature);
469 internal bool VerifySignature (RSA rsa)
471 RSAPKCS1SignatureDeformatter v = new RSAPKCS1SignatureDeformatter (rsa);
472 switch (m_signaturealgo) {
473 // MD2 with RSA encryption
474 case "1.2.840.113549.1.1.2":
475 // maybe someone installed MD2 ?
476 v.SetHashAlgorithm ("MD2");
478 // MD5 with RSA encryption
479 case "1.2.840.113549.1.1.4":
480 v.SetHashAlgorithm ("MD5");
482 // SHA-1 with RSA Encryption
483 case "1.2.840.113549.1.1.5":
484 case "1.3.14.3.2.29":
485 v.SetHashAlgorithm ("SHA1");
488 throw new CryptographicException ("Unsupported hash algorithm: " + m_signaturealgo);
490 return v.VerifySignature (this.Hash, this.Signature);
493 public bool VerifySignature (AsymmetricAlgorithm aa)
496 throw new ArgumentNullException ("aa");
499 return VerifySignature (aa as RSA);
501 return VerifySignature (aa as DSA);
503 throw new NotSupportedException ("Unknown Asymmetric Algorithm " + aa.ToString ());
506 public bool CheckSignature (byte[] hash, string hashAlgorithm, byte[] signature)
508 RSACryptoServiceProvider r = (RSACryptoServiceProvider) RSA;
509 return r.VerifyHash (hash, hashAlgorithm, signature);
512 public bool IsSelfSigned {
514 if (m_issuername == m_subject)
515 return VerifySignature (RSA);
521 #if INSIDE_CORLIB || NET_2_0
522 public ASN1 GetIssuerName ()
527 public ASN1 GetSubjectName ()
532 protected X509Certificate (SerializationInfo info, StreamingContext context)
534 Parse ((byte[]) info.GetValue ("raw", typeof (byte[])));
537 [SecurityPermission (SecurityAction.Demand, SerializationFormatter = true)]
538 public virtual void GetObjectData (SerializationInfo info, StreamingContext context)
540 info.AddValue ("raw", m_encodedcert);
541 // note: we NEVER serialize the private key
545 static byte[] PEM (string type, byte[] data)
547 string pem = Encoding.ASCII.GetString (data);
548 string header = String.Format ("-----BEGIN {0}-----", type);
549 string footer = String.Format ("-----END {0}-----", type);
550 int start = pem.IndexOf (header) + header.Length;
551 int end = pem.IndexOf (footer, start);
552 string base64 = pem.Substring (start, (end - start));
553 return Convert.FromBase64String (base64);