Comment charger la clé publique RSA à partir d'un fichier en C #
J'ai besoin de charger la clé publique RSA suivante à partir d'un fichier à utiliser avec la classe RSACryptoServiceProvider. Comment puis-je faire ceci?
-----BEGIN PUBLIC KEY-----
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/syEKqEkMtQL0+d
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX+izR
KbGMRtur2TYklnyVkjeeHfAggo8vWQmWesnOG55vQYHbOOFoJbk0EkwEr5R/PbKm
byXPPN8zwnS5/XXXXXXXXXXXX
-----END PUBLIC KEY-----
Ce code fonctionne avec ma clé de pub: http://www.jensign.com/opensslkey/
Voici le code que j'utilise
static string RSA(string input)
{
RSACryptoServiceProvider rsa = DecodeX509PublicKey(Convert.FromBase64String(GetKey()));
return (Convert.ToBase64String(rsa.Encrypt(Encoding.ASCII.GetBytes(input), false)));
}
static string GetKey()
{
return File.ReadAllText("master.pub").Replace("-----BEGIN PUBLIC KEY-----", "").Replace("-----END PUBLIC KEY-----", "");
//.Replace("\n", "");
}
private static bool CompareBytearrays(byte[] a, byte[] b)
{
if (a.Length != b.Length)
return false;
int i = 0;
foreach (byte c in a)
{
if (c != b[i])
return false;
i++;
}
return true;
}
public static RSACryptoServiceProvider DecodeX509PublicKey(byte[] x509key)
{
// encoded OID sequence for PKCS #1 rsaEncryption szOID_RSA_RSA = "1.2.840.113549.1.1.1"
byte[] SeqOID = { 0x30, 0x0D, 0x06, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01, 0x05, 0x00 };
byte[] seq = new byte[15];
// --------- Set up stream to read the asn.1 encoded SubjectPublicKeyInfo blob ------
MemoryStream mem = new MemoryStream(x509key);
BinaryReader binr = new BinaryReader(mem); //wrap Memory Stream with BinaryReader for easy reading
byte bt = 0;
ushort twobytes = 0;
try
{
twobytes = binr.ReadUInt16();
if (twobytes == 0x8130) //data read as little endian order (actual data order for Sequence is 30 81)
binr.ReadByte(); //advance 1 byte
else if (twobytes == 0x8230)
binr.ReadInt16(); //advance 2 bytes
else
return null;
seq = binr.ReadBytes(15); //read the Sequence OID
if (!CompareBytearrays(seq, SeqOID)) //make sure Sequence for OID is correct
return null;
twobytes = binr.ReadUInt16();
if (twobytes == 0x8103) //data read as little endian order (actual data order for Bit String is 03 81)
binr.ReadByte(); //advance 1 byte
else if (twobytes == 0x8203)
binr.ReadInt16(); //advance 2 bytes
else
return null;
bt = binr.ReadByte();
if (bt != 0x00) //expect null byte next
return null;
twobytes = binr.ReadUInt16();
if (twobytes == 0x8130) //data read as little endian order (actual data order for Sequence is 30 81)
binr.ReadByte(); //advance 1 byte
else if (twobytes == 0x8230)
binr.ReadInt16(); //advance 2 bytes
else
return null;
twobytes = binr.ReadUInt16();
byte lowbyte = 0x00;
byte highbyte = 0x00;
if (twobytes == 0x8102) //data read as little endian order (actual data order for Integer is 02 81)
lowbyte = binr.ReadByte(); // read next bytes which is bytes in modulus
else if (twobytes == 0x8202)
{
highbyte = binr.ReadByte(); //advance 2 bytes
lowbyte = binr.ReadByte();
}
else
return null;
byte[] modint = { lowbyte, highbyte, 0x00, 0x00 }; //reverse byte order since asn.1 key uses big endian order
int modsize = BitConverter.ToInt32(modint, 0);
byte firstbyte = binr.ReadByte();
binr.BaseStream.Seek(-1, SeekOrigin.Current);
if (firstbyte == 0x00)
{ //if first byte (highest order) of modulus is zero, don't include it
binr.ReadByte(); //skip this null byte
modsize -= 1; //reduce modulus buffer size by 1
}
byte[] modulus = binr.ReadBytes(modsize); //read the modulus bytes
if (binr.ReadByte() != 0x02) //expect an Integer for the exponent data
return null;
int expbytes = (int)binr.ReadByte(); // should only need one byte for actual exponent data (for all useful values)
byte[] exponent = binr.ReadBytes(expbytes);
// ------- create RSACryptoServiceProvider instance and initialize with public key -----
RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
RSAParameters RSAKeyInfo = new RSAParameters();
RSAKeyInfo.Modulus = modulus;
RSAKeyInfo.Exponent = exponent;
RSA.ImportParameters(RSAKeyInfo);
return RSA;
}
catch (Exception)
{
return null;
}
finally { binr.Close(); }
}
Appelez simplement la méthode "RSA" avec le texte que vous souhaitez crypter et vous avez terminé.
Vous pouvez créer un RSACryptoServiceProvider à partir d'un fichier PEM à l'aide de la classe suivante (méthode GetRSAProviderFromPemFile).
Avertissement: Ne copiez pas simplement le code de StackOverflow sans vérification! Surtout pas le code crypto! Ce code a des bugs (voir commentaires). Vous voudrez peut-être écrire et exécuter des tests avant de l'utiliser en production (si vous n'avez vraiment pas de meilleure option). Je refuse de modifier le code pour le corriger, car il serait tout aussi peu fiable que avant sans tests et un mainteneur actif.
Source: Ce code semble provenir de opensslkey de ce site . Copyright (c) 2000 JavaScience Consulting, Michel Gallant. Le package d'origine a été publié sous une licence de type BSD, il est donc probablement OK de l'utiliser (mais vous voudrez peut-être revérifier). Il y a aussi un package NuGet du même auteur.
Voici le code source copié-collé initialement publié pour cette réponse:
RSACryptoServiceProvider provider = PemKeyUtils.GetRSAProviderFromPemFile( @"public_key.pem" );
public class PemKeyUtils
{
const String pemprivheader = "-----BEGIN RSA PRIVATE KEY-----";
const String pemprivfooter = "-----END RSA PRIVATE KEY-----";
const String pempubheader = "-----BEGIN PUBLIC KEY-----";
const String pempubfooter = "-----END PUBLIC KEY-----";
const String pemp8header = "-----BEGIN PRIVATE KEY-----";
const String pemp8footer = "-----END PRIVATE KEY-----";
const String pemp8encheader = "-----BEGIN ENCRYPTED PRIVATE KEY-----";
const String pemp8encfooter = "-----END ENCRYPTED PRIVATE KEY-----";
static bool verbose = false;
public static RSACryptoServiceProvider GetRSAProviderFromPemFile( String pemfile )
{
bool isPrivateKeyFile = true;
string pemstr = File.ReadAllText( pemfile ).Trim();
if (pemstr.StartsWith( pempubheader ) && pemstr.EndsWith( pempubfooter ))
isPrivateKeyFile = false;
byte[] pemkey;
if (isPrivateKeyFile)
pemkey = DecodeOpenSSLPrivateKey( pemstr );
else
pemkey = DecodeOpenSSLPublicKey( pemstr );
if (pemkey == null)
return null;
if (isPrivateKeyFile)
return DecodeRSAPrivateKey( pemkey );
else
return DecodeX509PublicKey( pemkey );
}
//-------- Get the binary RSA PUBLIC key --------
static byte[] DecodeOpenSSLPublicKey( String instr )
{
const String pempubheader = "-----BEGIN PUBLIC KEY-----";
const String pempubfooter = "-----END PUBLIC KEY-----";
String pemstr = instr.Trim();
byte[] binkey;
if (!pemstr.StartsWith( pempubheader ) || !pemstr.EndsWith( pempubfooter ))
return null;
StringBuilder sb = new StringBuilder( pemstr );
sb.Replace( pempubheader, "" ); //remove headers/footers, if present
sb.Replace( pempubfooter, "" );
String pubstr = sb.ToString().Trim(); //get string after removing leading/trailing whitespace
try
{
binkey = Convert.FromBase64String( pubstr );
}
catch (System.FormatException)
{ //if can't b64 decode, data is not valid
return null;
}
return binkey;
}
static RSACryptoServiceProvider DecodeX509PublicKey(byte[] x509Key)
{
// encoded OID sequence for PKCS #1 rsaEncryption szOID_RSA_RSA = "1.2.840.113549.1.1.1"
byte[] seqOid = { 0x30, 0x0D, 0x06, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01, 0x05, 0x00 };
// --------- Set up stream to read the asn.1 encoded SubjectPublicKeyInfo blob ------
using (var mem = new MemoryStream(x509Key))
{
using (var binr = new BinaryReader(mem)) //wrap Memory Stream with BinaryReader for easy reading
{
try
{
var twobytes = binr.ReadUInt16();
switch (twobytes)
{
case 0x8130:
binr.ReadByte(); //advance 1 byte
break;
case 0x8230:
binr.ReadInt16(); //advance 2 bytes
break;
default:
return null;
}
var seq = binr.ReadBytes(15);
if (!CompareBytearrays(seq, seqOid)) //make sure Sequence for OID is correct
return null;
twobytes = binr.ReadUInt16();
if (twobytes == 0x8103) //data read as little endian order (actual data order for Bit String is 03 81)
binr.ReadByte(); //advance 1 byte
else if (twobytes == 0x8203)
binr.ReadInt16(); //advance 2 bytes
else
return null;
var bt = binr.ReadByte();
if (bt != 0x00) //expect null byte next
return null;
twobytes = binr.ReadUInt16();
if (twobytes == 0x8130) //data read as little endian order (actual data order for Sequence is 30 81)
binr.ReadByte(); //advance 1 byte
else if (twobytes == 0x8230)
binr.ReadInt16(); //advance 2 bytes
else
return null;
twobytes = binr.ReadUInt16();
byte lowbyte = 0x00;
byte highbyte = 0x00;
if (twobytes == 0x8102) //data read as little endian order (actual data order for Integer is 02 81)
lowbyte = binr.ReadByte(); // read next bytes which is bytes in modulus
else if (twobytes == 0x8202)
{
highbyte = binr.ReadByte(); //advance 2 bytes
lowbyte = binr.ReadByte();
}
else
return null;
byte[] modint = { lowbyte, highbyte, 0x00, 0x00 }; //reverse byte order since asn.1 key uses big endian order
int modsize = BitConverter.ToInt32(modint, 0);
byte firstbyte = binr.ReadByte();
binr.BaseStream.Seek(-1, SeekOrigin.Current);
if (firstbyte == 0x00)
{ //if first byte (highest order) of modulus is zero, don't include it
binr.ReadByte(); //skip this null byte
modsize -= 1; //reduce modulus buffer size by 1
}
byte[] modulus = binr.ReadBytes(modsize); //read the modulus bytes
if (binr.ReadByte() != 0x02) //expect an Integer for the exponent data
return null;
int expbytes = binr.ReadByte(); // should only need one byte for actual exponent data (for all useful values)
byte[] exponent = binr.ReadBytes(expbytes);
// We don't really need to print anything but if we insist to...
//showBytes("\nExponent", exponent);
//showBytes("\nModulus", modulus);
// ------- create RSACryptoServiceProvider instance and initialize with public key -----
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
RSAParameters rsaKeyInfo = new RSAParameters
{
Modulus = modulus,
Exponent = exponent
};
rsa.ImportParameters(rsaKeyInfo);
return rsa;
}
catch (Exception)
{
return null;
}
}
}
}
//------- Parses binary ans.1 RSA private key; returns RSACryptoServiceProvider ---
static RSACryptoServiceProvider DecodeRSAPrivateKey( byte[] privkey )
{
byte[] MODULUS, E, D, P, Q, DP, DQ, IQ;
// --------- Set up stream to decode the asn.1 encoded RSA private key ------
MemoryStream mem = new MemoryStream( privkey );
BinaryReader binr = new BinaryReader( mem ); //wrap Memory Stream with BinaryReader for easy reading
byte bt = 0;
ushort twobytes = 0;
int elems = 0;
try
{
twobytes = binr.ReadUInt16();
if (twobytes == 0x8130) //data read as little endian order (actual data order for Sequence is 30 81)
binr.ReadByte(); //advance 1 byte
else if (twobytes == 0x8230)
binr.ReadInt16(); //advance 2 bytes
else
return null;
twobytes = binr.ReadUInt16();
if (twobytes != 0x0102) //version number
return null;
bt = binr.ReadByte();
if (bt != 0x00)
return null;
//------ all private key components are Integer sequences ----
elems = GetIntegerSize( binr );
MODULUS = binr.ReadBytes( elems );
elems = GetIntegerSize( binr );
E = binr.ReadBytes( elems );
elems = GetIntegerSize( binr );
D = binr.ReadBytes( elems );
elems = GetIntegerSize( binr );
P = binr.ReadBytes( elems );
elems = GetIntegerSize( binr );
Q = binr.ReadBytes( elems );
elems = GetIntegerSize( binr );
DP = binr.ReadBytes( elems );
elems = GetIntegerSize( binr );
DQ = binr.ReadBytes( elems );
elems = GetIntegerSize( binr );
IQ = binr.ReadBytes( elems );
Console.WriteLine( "showing components .." );
if (verbose)
{
showBytes( "\nModulus", MODULUS );
showBytes( "\nExponent", E );
showBytes( "\nD", D );
showBytes( "\nP", P );
showBytes( "\nQ", Q );
showBytes( "\nDP", DP );
showBytes( "\nDQ", DQ );
showBytes( "\nIQ", IQ );
}
// ------- create RSACryptoServiceProvider instance and initialize with public key -----
RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
RSAParameters RSAparams = new RSAParameters();
RSAparams.Modulus = MODULUS;
RSAparams.Exponent = E;
RSAparams.D = D;
RSAparams.P = P;
RSAparams.Q = Q;
RSAparams.DP = DP;
RSAparams.DQ = DQ;
RSAparams.InverseQ = IQ;
RSA.ImportParameters( RSAparams );
return RSA;
}
catch (Exception)
{
return null;
}
finally { binr.Close(); }
}
private static int GetIntegerSize( BinaryReader binr )
{
byte bt = 0;
byte lowbyte = 0x00;
byte highbyte = 0x00;
int count = 0;
bt = binr.ReadByte();
if (bt != 0x02) //expect integer
return 0;
bt = binr.ReadByte();
if (bt == 0x81)
count = binr.ReadByte(); // data size in next byte
else
if (bt == 0x82)
{
highbyte = binr.ReadByte(); // data size in next 2 bytes
lowbyte = binr.ReadByte();
byte[] modint = { lowbyte, highbyte, 0x00, 0x00 };
count = BitConverter.ToInt32( modint, 0 );
}
else
{
count = bt; // we already have the data size
}
while (binr.ReadByte() == 0x00)
{ //remove high order zeros in data
count -= 1;
}
binr.BaseStream.Seek( -1, SeekOrigin.Current ); //last ReadByte wasn't a removed zero, so back up a byte
return count;
}
//----- Get the binary RSA PRIVATE key, decrypting if necessary ----
static byte[] DecodeOpenSSLPrivateKey( String instr )
{
const String pemprivheader = "-----BEGIN RSA PRIVATE KEY-----";
const String pemprivfooter = "-----END RSA PRIVATE KEY-----";
String pemstr = instr.Trim();
byte[] binkey;
if (!pemstr.StartsWith( pemprivheader ) || !pemstr.EndsWith( pemprivfooter ))
return null;
StringBuilder sb = new StringBuilder( pemstr );
sb.Replace( pemprivheader, "" ); //remove headers/footers, if present
sb.Replace( pemprivfooter, "" );
String pvkstr = sb.ToString().Trim(); //get string after removing leading/trailing whitespace
try
{ // if there are no PEM encryption info lines, this is an UNencrypted PEM private key
binkey = Convert.FromBase64String( pvkstr );
return binkey;
}
catch (System.FormatException)
{ //if can't b64 decode, it must be an encrypted private key
//Console.WriteLine("Not an unencrypted OpenSSL PEM private key");
}
StringReader str = new StringReader( pvkstr );
//-------- read PEM encryption info. lines and extract salt -----
if (!str.ReadLine().StartsWith( "Proc-Type: 4,ENCRYPTED" ))
return null;
String saltline = str.ReadLine();
if (!saltline.StartsWith( "DEK-Info: DES-EDE3-CBC," ))
return null;
String saltstr = saltline.Substring( saltline.IndexOf( "," ) + 1 ).Trim();
byte[] salt = new byte[saltstr.Length / 2];
for (int i = 0; i < salt.Length; i++)
salt[i] = Convert.ToByte( saltstr.Substring( i * 2, 2 ), 16 );
if (!(str.ReadLine() == ""))
return null;
//------ remaining b64 data is encrypted RSA key ----
String encryptedstr = str.ReadToEnd();
try
{ //should have b64 encrypted RSA key now
binkey = Convert.FromBase64String( encryptedstr );
}
catch (System.FormatException)
{ // bad b64 data.
return null;
}
//------ Get the 3DES 24 byte key using PDK used by OpenSSL ----
SecureString despswd = GetSecPswd( "Enter password to derive 3DES key==>" );
//Console.Write("\nEnter password to derive 3DES key: ");
//String pswd = Console.ReadLine();
byte[] deskey = GetOpenSSL3deskey( salt, despswd, 1, 2 ); // count=1 (for OpenSSL implementation); 2 iterations to get at least 24 bytes
if (deskey == null)
return null;
//showBytes("3DES key", deskey) ;
//------ Decrypt the encrypted 3des-encrypted RSA private key ------
byte[] rsakey = DecryptKey( binkey, deskey, salt ); //OpenSSL uses salt value in PEM header also as 3DES IV
if (rsakey != null)
return rsakey; //we have a decrypted RSA private key
else
{
Console.WriteLine( "Failed to decrypt RSA private key; probably wrong password." );
return null;
}
}
// ----- Decrypt the 3DES encrypted RSA private key ----------
static byte[] DecryptKey( byte[] cipherData, byte[] desKey, byte[] IV )
{
MemoryStream memst = new MemoryStream();
TripleDES alg = TripleDES.Create();
alg.Key = desKey;
alg.IV = IV;
try
{
CryptoStream cs = new CryptoStream( memst, alg.CreateDecryptor(), CryptoStreamMode.Write );
cs.Write( cipherData, 0, cipherData.Length );
cs.Close();
}
catch (Exception exc)
{
Console.WriteLine( exc.Message );
return null;
}
byte[] decryptedData = memst.ToArray();
return decryptedData;
}
//----- OpenSSL PBKD uses only one hash cycle (count); miter is number of iterations required to build sufficient bytes ---
static byte[] GetOpenSSL3deskey( byte[] salt, SecureString secpswd, int count, int miter )
{
IntPtr unmanagedPswd = IntPtr.Zero;
int HASHLENGTH = 16; //MD5 bytes
byte[] keymaterial = new byte[HASHLENGTH * miter]; //to store contatenated Mi hashed results
byte[] psbytes = new byte[secpswd.Length];
unmanagedPswd = Marshal.SecureStringToGlobalAllocAnsi( secpswd );
Marshal.Copy( unmanagedPswd, psbytes, 0, psbytes.Length );
Marshal.ZeroFreeGlobalAllocAnsi( unmanagedPswd );
//UTF8Encoding utf8 = new UTF8Encoding();
//byte[] psbytes = utf8.GetBytes(pswd);
// --- contatenate salt and pswd bytes into fixed data array ---
byte[] data00 = new byte[psbytes.Length + salt.Length];
Array.Copy( psbytes, data00, psbytes.Length ); //copy the pswd bytes
Array.Copy( salt, 0, data00, psbytes.Length, salt.Length ); //concatenate the salt bytes
// ---- do multi-hashing and contatenate results D1, D2 ... into keymaterial bytes ----
MD5 md5 = new MD5CryptoServiceProvider();
byte[] result = null;
byte[] hashtarget = new byte[HASHLENGTH + data00.Length]; //fixed length initial hashtarget
for (int j = 0; j < miter; j++)
{
// ---- Now hash consecutively for count times ------
if (j == 0)
result = data00; //initialize
else
{
Array.Copy( result, hashtarget, result.Length );
Array.Copy( data00, 0, hashtarget, result.Length, data00.Length );
result = hashtarget;
//Console.WriteLine("Updated new initial hash target:") ;
//showBytes(result) ;
}
for (int i = 0; i < count; i++)
result = md5.ComputeHash( result );
Array.Copy( result, 0, keymaterial, j * HASHLENGTH, result.Length ); //contatenate to keymaterial
}
//showBytes("Final key material", keymaterial);
byte[] deskey = new byte[24];
Array.Copy( keymaterial, deskey, deskey.Length );
Array.Clear( psbytes, 0, psbytes.Length );
Array.Clear( data00, 0, data00.Length );
Array.Clear( result, 0, result.Length );
Array.Clear( hashtarget, 0, hashtarget.Length );
Array.Clear( keymaterial, 0, keymaterial.Length );
return deskey;
}
static SecureString GetSecPswd( String Prompt )
{
SecureString password = new SecureString();
Console.ForegroundColor = ConsoleColor.Gray;
Console.Write( Prompt );
Console.ForegroundColor = ConsoleColor.Magenta;
while (true)
{
ConsoleKeyInfo cki = Console.ReadKey( true );
if (cki.Key == ConsoleKey.Enter)
{
Console.ForegroundColor = ConsoleColor.Gray;
Console.WriteLine();
return password;
}
else if (cki.Key == ConsoleKey.Backspace)
{
// remove the last asterisk from the screen...
if (password.Length > 0)
{
Console.SetCursorPosition( Console.CursorLeft - 1, Console.CursorTop );
Console.Write( " " );
Console.SetCursorPosition( Console.CursorLeft - 1, Console.CursorTop );
password.RemoveAt( password.Length - 1 );
}
}
else if (cki.Key == ConsoleKey.Escape)
{
Console.ForegroundColor = ConsoleColor.Gray;
Console.WriteLine();
return password;
}
else if (Char.IsLetterOrDigit( cki.KeyChar ) || Char.IsSymbol( cki.KeyChar ))
{
if (password.Length < 20)
{
password.AppendChar( cki.KeyChar );
Console.Write( "*" );
}
else
{
Console.Beep();
}
}
else
{
Console.Beep();
}
}
}
static bool CompareBytearrays( byte[] a, byte[] b )
{
if (a.Length != b.Length)
return false;
int i = 0;
foreach (byte c in a)
{
if (c != b[i])
return false;
i++;
}
return true;
}
static void showBytes( String info, byte[] data )
{
Console.WriteLine( "{0} [{1} bytes]", info, data.Length );
for (int i = 1; i <= data.Length; i++)
{
Console.Write( "{0:X2} ", data[i - 1] );
if (i % 16 == 0)
Console.WriteLine();
}
Console.WriteLine( "\n\n" );
}
}
Si vous parlez d'un certificat X509:
FileStream fs = new FileStream("your_cert_file.crt", FileMode.Open);
byte[] certBytes = new byte[fs.Length];
fs.Read(certBytes, 0, (Int32)fs.Length);
fs.Close();
System.Security.Cryptography.X509Certificates.X509Certificate x509cert =
new X509Certificate(certBytes);
Console.WriteLine(x509cert.GetPublicKey());
Console.WriteLine(x509cert.GetPublicKeyString());
MODIFIÉ après le commentaire de @hkproj fait dans "16/07/2012 15:04:58 Z":
En regardant ici, j'ai trouvé " Lecture de la clé publique PEM RSA uniquement en utilisant Bouncy Castle ". Je suppose que ce que vous voulez est le suivant:
using (StreamReader reader = File.OpenText(@"c:\RSA.txt"))
{
Org.BouncyCastle.OpenSsl.PemReader pr =
new Org.BouncyCastle.OpenSsl.PemReader(reader);
Org.BouncyCastle.Utilities.IO.Pem.PemObject po = pr.ReadPemObject();
Console.WriteLine("PemObject, Type: " + po.Type);
Console.WriteLine("PemObject, Length: " + po.Content.Length);
}
Cependant, avec votre fichier, j'obtiens une erreur: System.IO.IOException : base64 data appears to be truncated.
Donc, changer votre fichier en quelque chose comme:
-----BEGIN PUBLIC KEY-----
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/syEKqEkMtQL0+d
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX+izR
KbGMRtur2TYklnyVkjeeHfAggo8vWQmWesnOG55vQYHbOOFoJbk0EkwEr5R/PbKm
byXPPN8zwnS5/XXXXXXXXXXXXZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
-----END PUBLIC KEY-----
Le résultat est:
PemObject, Type: PUBLIC KEY
PemObject, Length: 192
Parlez-vous de certificats stockés dans un fichier?
Si vous avez un objet comme:
X509Certificate2 certificate;
vous pouvez utiliser le code suivant:
RSACryptoServiceProvider rsaprovider =
(RSACryptoServiceProvider)certificate.PublicKey.Key;
puis utilisez la classe RSACryptoServiceProvider (voir http://msdn.Microsoft.com/en-us/library/system.security.cryptography.rsacryptoserviceprovider.aspx ).
Pour charger un X509Certificate2, utilisez son constructeur (voir http://msdn.Microsoft.com/en-us/library/system.security.cryptography.x509certificates.x509certificate2.aspx ).
Ce programme fonctionne bien pour moi:
static void Main(string[] args)
{
try
{
X509Certificate2 certificate =
new X509Certificate2("<PFX Certificate Path", "<Certificate-Password>");
RSACryptoServiceProvider rsaprovider = (RSACryptoServiceProvider)certificate.PublicKey.Key;
}
catch(Exception e)
{
}
}