static Stream Encrypt (PgpEncryptedDataGenerator encrypter, Stream content)
{
var memory = new MemoryBlockStream ();
using (var armored = new ArmoredOutputStream (memory)) {
using (var compressed = Compress (content)) {
using (var encrypted = encrypter.Open (armored, compressed.Length)) {
compressed.CopyTo (encrypted, 4096);
encrypted.Flush ();
}
}
armored.Flush ();
}
memory.Position = 0;
return memory;
}
/// <summary>
/// Exports the specified public keys.
/// </summary>
/// <remarks>
/// Exports the specified public keys.
/// </remarks>
/// <returns>A new <see cref="MimeKit.MimePart"/> instance containing the exported public keys.</returns>
/// <param name="keys">The keys.</param>
/// <exception cref="System.ArgumentNullException">
/// <paramref name="keys"/> is <c>null</c>.
/// </exception>
public MimePart Export (PgpPublicKeyRingBundle keys)
{
if (keys == null)
throw new ArgumentNullException ("keys");
var content = new MemoryBlockStream ();
using (var armored = new ArmoredOutputStream (content)) {
keys.Encode (armored);
armored.Flush ();
}
content.Position = 0;
return new MimePart ("application", "pgp-keys") {
ContentDisposition = new ContentDisposition ("attachment"),
ContentObject = new ContentObject (content)
};
}
/// <summary>
/// Cryptographically signs the content.
/// </summary>
/// <remarks>
/// Cryptographically signs the content using the specified signer and digest algorithm.
/// </remarks>
/// <returns>A new <see cref="MimeKit.MimePart"/> instance
/// containing the detached signature data.</returns>
/// <param name="signer">The signer.</param>
/// <param name="digestAlgo">The digest algorithm to use for signing.</param>
/// <param name="content">The content.</param>
/// <exception cref="System.ArgumentNullException">
/// <para><paramref name="signer"/> is <c>null</c>.</para>
/// <para>-or-</para>
/// <para><paramref name="content"/> is <c>null</c>.</para>
/// </exception>
/// <exception cref="System.ArgumentException">
/// <paramref name="signer"/> cannot be used for signing.
/// </exception>
/// <exception cref="System.ArgumentOutOfRangeException">
/// The <paramref name="digestAlgo"/> was out of range.
/// </exception>
/// <exception cref="System.NotSupportedException">
/// The <paramref name="digestAlgo"/> is not supported.
/// </exception>
/// <exception cref="System.OperationCanceledException">
/// The user chose to cancel the password prompt.
/// </exception>
/// <exception cref="System.UnauthorizedAccessException">
/// 3 bad attempts were made to unlock the secret key.
/// </exception>
public ApplicationPgpSignature Sign (PgpSecretKey signer, DigestAlgorithm digestAlgo, Stream content)
{
if (signer == null)
throw new ArgumentNullException ("signer");
if (!signer.IsSigningKey)
throw new ArgumentException ("The specified secret key cannot be used for signing.", "signer");
if (content == null)
throw new ArgumentNullException ("content");
var hashAlgorithm = GetHashAlgorithm (digestAlgo);
var memory = new MemoryBlockStream ();
using (var armored = new ArmoredOutputStream (memory)) {
var compresser = new PgpCompressedDataGenerator (CompressionAlgorithmTag.ZLib);
using (var compressed = compresser.Open (armored)) {
var signatureGenerator = new PgpSignatureGenerator (signer.PublicKey.Algorithm, hashAlgorithm);
var buf = new byte[4096];
int nread;
signatureGenerator.InitSign (PgpSignature.CanonicalTextDocument, GetPrivateKey (signer));
while ((nread = content.Read (buf, 0, buf.Length)) > 0)
signatureGenerator.Update (buf, 0, nread);
var signature = signatureGenerator.Generate ();
signature.Encode (compressed);
compressed.Flush ();
}
armored.Flush ();
}
memory.Position = 0;
return new ApplicationPgpSignature (memory);
}
/// <summary>
/// Cryptographically signs and encrypts the specified content for the specified recipients.
/// </summary>
/// <remarks>
/// Cryptographically signs and encrypts the specified content for the specified recipients.
/// </remarks>
/// <returns>A new <see cref="MimeKit.MimePart"/> instance
/// containing the encrypted data.</returns>
/// <param name="signer">The signer.</param>
/// <param name="digestAlgo">The digest algorithm to use for signing.</param>
/// <param name="cipherAlgo">The encryption algorithm.</param>
/// <param name="recipients">The recipients.</param>
/// <param name="content">The content.</param>
/// <exception cref="System.ArgumentNullException">
/// <para><paramref name="signer"/> is <c>null</c>.</para>
/// <para>-or-</para>
/// <para><paramref name="recipients"/> is <c>null</c>.</para>
/// <para>-or-</para>
/// <para><paramref name="content"/> is <c>null</c>.</para>
/// </exception>
/// <exception cref="System.ArgumentException">
/// <para><paramref name="signer"/> cannot be used for signing.</para>
/// <para>-or-</para>
/// <para>One or more of the recipient keys cannot be used for encrypting.</para>
/// <para>-or-</para>
/// <para>No recipients were specified.</para>
/// </exception>
/// <exception cref="System.NotSupportedException">
/// The specified encryption algorithm is not supported.
/// </exception>
/// <exception cref="System.OperationCanceledException">
/// The user chose to cancel the password prompt.
/// </exception>
/// <exception cref="System.UnauthorizedAccessException">
/// 3 bad attempts were made to unlock the secret key.
/// </exception>
public MimePart SignAndEncrypt (PgpSecretKey signer, DigestAlgorithm digestAlgo, EncryptionAlgorithm cipherAlgo, IEnumerable<PgpPublicKey> recipients, Stream content)
{
// TODO: document the exceptions that can be thrown by BouncyCastle
if (signer == null)
throw new ArgumentNullException ("signer");
if (!signer.IsSigningKey)
throw new ArgumentException ("The specified secret key cannot be used for signing.", "signer");
if (recipients == null)
throw new ArgumentNullException ("recipients");
if (content == null)
throw new ArgumentNullException ("content");
var encrypter = new PgpEncryptedDataGenerator (GetSymmetricKeyAlgorithm (cipherAlgo), true);
var hashAlgorithm = GetHashAlgorithm (digestAlgo);
int count = 0;
foreach (var recipient in recipients) {
if (!recipient.IsEncryptionKey)
throw new ArgumentException ("One or more of the recipient keys cannot be used for encrypting.", "recipients");
encrypter.AddMethod (recipient);
count++;
}
if (count == 0)
throw new ArgumentException ("No recipients specified.", "recipients");
var compresser = new PgpCompressedDataGenerator (CompressionAlgorithmTag.ZLib);
using (var compressed = new MemoryBlockStream ()) {
using (var signed = compresser.Open (compressed)) {
var signatureGenerator = new PgpSignatureGenerator (signer.PublicKey.Algorithm, hashAlgorithm);
signatureGenerator.InitSign (PgpSignature.CanonicalTextDocument, GetPrivateKey (signer));
var subpacket = new PgpSignatureSubpacketGenerator ();
foreach (string userId in signer.PublicKey.GetUserIds ()) {
subpacket.SetSignerUserId (false, userId);
break;
}
signatureGenerator.SetHashedSubpackets (subpacket.Generate ());
var onepass = signatureGenerator.GenerateOnePassVersion (false);
onepass.Encode (signed);
var literalGenerator = new PgpLiteralDataGenerator ();
using (var literal = literalGenerator.Open (signed, 't', "mime.txt", content.Length, DateTime.Now)) {
var buf = new byte[4096];
int nread;
while ((nread = content.Read (buf, 0, buf.Length)) > 0) {
signatureGenerator.Update (buf, 0, nread);
literal.Write (buf, 0, nread);
}
literal.Flush ();
}
var signature = signatureGenerator.Generate ();
signature.Encode (signed);
signed.Flush ();
}
compressed.Position = 0;
var memory = new MemoryBlockStream ();
using (var armored = new ArmoredOutputStream (memory)) {
using (var encrypted = encrypter.Open (armored, compressed.Length)) {
compressed.CopyTo (encrypted, 4096);
encrypted.Flush ();
}
armored.Flush ();
}
memory.Position = 0;
return new MimePart ("application", "octet-stream") {
ContentDisposition = new ContentDisposition ("attachment"),
ContentObject = new ContentObject (memory)
};
}
}