//
// This file is part of the source code distribution of SharpPrivacy.
// SharpPrivacy is an Open Source OpenPGP implementation and can be
// found at http://www.sharpprivacy.net
// It is released under Gnu General Public License and can be used
// and modified as long as the result is released under GPL too.
// For a copy of the GPL, please go to www.gnu.org/copyleft/gpl.html
//
// TransportablePublicKey.cs:
// Class for handling public keys in their transportable format.
//
// Author:
// Daniel Fabian (df@sharpprivacy.net)
//
//
// Version: 0.1.0 (initial release)
//
// Changelog:
// - 23.02.2003: Created this file.
// - 01.06.2003: Added this header for the first beta release.
//
// (C) 2003, Daniel Fabian
//
using System;
using System.Windows.Forms;
using SharpPrivacy.Cipher;
using System.Collections;
namespace SharpPrivacy.OpenPGP.Messages {
/// <summary>
/// Transportable Public Key is an OpenPGP message as specified in
/// RFC2440. It contains a user's public key, its subkeys, any user
/// ids as well as certifications (signatures).
/// </summary>
/// <remarks>
/// Transportable Public Key is an OpenPGP message as specified in
/// RFC2440. It contains a user's public key, its subkeys, any user
/// ids as well as certifications (signatures).
/// </remarks>
public class TransportablePublicKey {
private PublicKeyPacket pkpPrimaryKey;
private ArrayList alRevocationSignatures;
private ArrayList alCertifications;
private ArrayList alSubkeys;
private string strPrimaryUserID;
/// <summary>
/// Creates a new Transportable secret key with the
/// parameters of the base64 encoded key given as
/// argument.
/// </summary>
/// <param name="strBase64">A transportable public key
/// encoded in base64.</param>
/// <remarks>No remarks</remarks>
public TransportablePublicKey(string strBase64) {
alRevocationSignatures = new ArrayList();
alCertifications = new ArrayList();
alSubkeys = new ArrayList();
strPrimaryUserID = "";
this.Parse(strBase64);
}
/// <summary>
/// Creates a new Transportable public key. No special
/// preferences are choses.
/// </summary>
/// <remarks>No remarks</remarks>
public TransportablePublicKey() {
alRevocationSignatures = new ArrayList();
alCertifications = new ArrayList();
alSubkeys = new ArrayList();
strPrimaryUserID = "";
}
/// <summary>
/// Readonly. Returns the primary user id of the transportable
/// public key.
/// </summary>
/// <remarks>No remarks</remarks>
/// <value>
/// Readonly. Returns the primary user id of the transportable
/// public key.
/// </value>
public string PrimaryUserID {
get {
if (strPrimaryUserID.Length == 0)
strPrimaryUserID = FindPrimaryUserID();
return strPrimaryUserID;
}
}
public DateTime KeyExpirationTime {
get {
DateTime dtExpiration = this.FindExpirationDate();
return new DateTime(this.PrimaryKey.TimeCreated.Ticks + (dtExpiration.Ticks - new DateTime(1970, 1, 1).Ticks));
}
}
/// <summary>
/// Gets or sets the primary key of the transportable public key.
/// </summary>
/// <remarks>No remarks</remarks>
/// <value>
/// Gets or sets the primary key of the transportable public key.
/// </value>
public PublicKeyPacket PrimaryKey {
get {
return pkpPrimaryKey;
}
set {
pkpPrimaryKey = value;
}
}
/// <summary>
/// An arraylist containing revocation signatures for the key.
/// </summary>
/// <remarks>No remarks</remarks>
/// <value>
/// An arraylist containing revocation signatures for the key.
/// </value>
public ArrayList RevocationSignatures {
get {
return alRevocationSignatures;
}
set {
alRevocationSignatures = value;
}
}
/// <summary>
/// An Arraylist containing certifications (trust signatures)
/// for the key.
/// </summary>
/// <remarks>No remarks</remarks>
/// <value>
/// An Arraylist containing certifications (trust signatures)
/// for the key.
/// </value>
public ArrayList Certifications {
get {
return alCertifications;
}
set {
alCertifications = value;
}
}
/// <summary>
/// An arraylist containing all the subkeys belonging to the
/// key.
/// </summary>
/// <remarks>No remarks</remarks>
/// <value>
/// An arraylist containing all the subkeys belonging to the
/// key.
/// </value>
public ArrayList SubKeys {
get {
return alSubkeys;
}
set {
alSubkeys = value;
}
}
/// <summary>
/// Returns a string representation of the transportable public key.
/// </summary>
/// <remarks>No remarks</remarks>
/// <returns>Returns a string representation of the transportable
/// public key.</returns>
public override string ToString() {
string strReturn = "";
strReturn += "Abstract:\r\n";
strReturn += "Number of Certificates: " + this.Certifications.Count + "\r\n";
strReturn += "\r\n\r\n\r\nPublic Key Packet: \r\n";
strReturn += this.PrimaryKey.ToString() + "\r\n\r\n";
IEnumerator ieLoop = this.Certifications.GetEnumerator();
while (ieLoop.MoveNext()) {
if (ieLoop.Current is CertifiedUserID) {
CertifiedUserID cuiUserID = (CertifiedUserID)ieLoop.Current;
strReturn += cuiUserID.ToString();
}
}
return strReturn;
}
/// <summary>
/// Generates the transportable public key out of the properties
/// in this.
/// </summary>
/// <remarks>No remarks</remarks>
/// <returns>Returns a byte array containing the openpgp encoded
/// representation of the transportable public key.</returns>
public byte[] Generate() {
byte[] bPrimaryKey = this.PrimaryKey.Generate();
//Revocation signatures
int iLength = 0;
IEnumerator ieRevocations = this.RevocationSignatures.GetEnumerator();
while (ieRevocations.MoveNext()) {
if (ieRevocations.Current is SignaturePacket) {
iLength += ((SignaturePacket)ieRevocations.Current).Generate().Length;
}
}
byte[] bRevocations = new byte[iLength];
ieRevocations = this.RevocationSignatures.GetEnumerator();
int iPosition = 0;
while (ieRevocations.MoveNext()) {
if (ieRevocations.Current is SignaturePacket) {
byte[] bRev = ((SignaturePacket)ieRevocations.Current).Generate();
Array.Copy(bRev, 0, bRevocations, iPosition, bRev.Length);
iPosition += bRev.Length;
}
}
//Certificates
iLength = 0;
IEnumerator ieCertificates = this.Certifications.GetEnumerator();
while (ieCertificates.MoveNext()) {
if (ieCertificates.Current is CertifiedUserID) {
CertifiedUserID cuiID = (CertifiedUserID)ieCertificates.Current;
iLength += cuiID.Generate().Length;
}
}
byte[] bCertificates = new byte[iLength];
iPosition = 0;
ieCertificates = this.Certifications.GetEnumerator();
while (ieCertificates.MoveNext()) {
if (ieCertificates.Current is CertifiedUserID) {
CertifiedUserID cuiID = (CertifiedUserID)ieCertificates.Current;
byte[] bCert = cuiID.Generate();
Array.Copy(bCert, 0, bCertificates, iPosition, bCert.Length);
iPosition += bCert.Length;
}
}
//SubKeys
iLength = 0;
IEnumerator ieSubkeys = this.SubKeys.GetEnumerator();
while (ieSubkeys.MoveNext()) {
if (ieSubkeys.Current is CertifiedPublicSubkey) {
CertifiedPublicSubkey cpsKey = (CertifiedPublicSubkey)ieSubkeys.Current;
iLength += cpsKey.Generate().Length;
}
}
byte[] bSubkeys = new byte[iLength];
iPosition = 0;
ieSubkeys = this.SubKeys.GetEnumerator();
while (ieSubkeys.MoveNext()) {
if (ieSubkeys.Current is CertifiedPublicSubkey) {
CertifiedPublicSubkey cpsKey = (CertifiedPublicSubkey)ieSubkeys.Current;
byte[] bKey = cpsKey.Generate();
Array.Copy(bKey, 0, bSubkeys, iPosition, bKey.Length);
iPosition += bKey.Length;
}
}
byte[] bData = new byte[bPrimaryKey.Length + bRevocations.Length +
bCertificates.Length + bSubkeys.Length];
iPosition = 0;
Array.Copy(bPrimaryKey, bData, bPrimaryKey.Length);
iPosition = bPrimaryKey.Length;
Array.Copy(bRevocations, 0, bData, iPosition, bRevocations.Length);
iPosition += bRevocations.Length;
Array.Copy(bCertificates, 0, bData, iPosition, bCertificates.Length);
iPosition += bCertificates.Length;
Array.Copy(bSubkeys, 0, bData, iPosition, bSubkeys.Length);
return bData;
}
/// <summary>
/// Finds a subkey (or the primary key) with the given keyid
/// and returns it. Returns null if the the fitting key has
/// not been found.
/// </summary>
/// <remarks>If the public key has been revoked, it is ignored
/// and NOT found by this function!!!</remarks>
/// <param name="lKeyID">The keyid to be sought in the transportable
/// public key.</param>
/// <returns>The subkey (or the primary key) with the given keyid.
/// Null if the the fitting key has not been found.</returns>
public PublicKeyPacket FindKey(ulong lKeyID) {
if (pkpPrimaryKey.KeyID == lKeyID)
return pkpPrimaryKey;
IEnumerator ieSubkeys = alSubkeys.GetEnumerator();
while (ieSubkeys.MoveNext()) {
CertifiedPublicSubkey cpsKey = (CertifiedPublicSubkey)ieSubkeys.Current;
// The subkey has been revoced
if (cpsKey.RevocationSignature != null)
continue;
PublicKeyPacket pkpKey = cpsKey.Subkey;
if (pkpKey.KeyID == lKeyID)
return pkpKey;
}
return null;
}
/// <summary>
/// Finds a subkey (or the primary key) that fits to the given
/// requirements (meaning it must be supposed to be used for
/// the given action, which can be either signing or encryption).
/// If more than just one keys fullfill the requirements, the one
/// with the newer creationdate is used.
/// </summary>
/// <remarks>No remarks</remarks>
/// <param name="aaAction">The action (signing or encrypting) for
/// which the key should be used</param>
/// <returns>Returns a public key packet fullfilling the given
/// requirements (the action) or null, if it did not find such
/// a key.</returns>
public PublicKeyPacket FindKey(AsymActions aaAction) {
DateTime dtCandidateTime = DateTime.Now;
PublicKeyPacket pkpCandidate = new PublicKeyPacket();
bool bFound = false;
// First check the primary Key
if (aaAction == AsymActions.Encrypt) {
if (pkpPrimaryKey.Algorithm == AsymAlgorithms.ElGama_Encrypt_Sign ||
pkpPrimaryKey.Algorithm == AsymAlgorithms.ElGamal_Encrypt_Only ||
pkpPrimaryKey.Algorithm == AsymAlgorithms.RSA_Encrypt_Only ||
pkpPrimaryKey.Algorithm == AsymAlgorithms.RSA_Encrypt_Sign) {
dtCandidateTime = pkpPrimaryKey.TimeCreated;
bFound = true;
pkpCandidate = pkpPrimaryKey;
}
} else if (aaAction == AsymActions.Sign) {
if (pkpPrimaryKey.Algorithm == AsymAlgorithms.ElGama_Encrypt_Sign ||
pkpPrimaryKey.Algorithm == AsymAlgorithms.DSA ||
pkpPrimaryKey.Algorithm == AsymAlgorithms.RSA_Sign_Only ||
pkpPrimaryKey.Algorithm == AsymAlgorithms.RSA_Encrypt_Sign) {
dtCandidateTime = pkpPrimaryKey.TimeCreated;
bFound = true;
pkpCandidate = pkpPrimaryKey;
}
}
// Now check the subkeys
IEnumerator ieSubkeys = alSubkeys.GetEnumerator();
while (ieSubkeys.MoveNext()) {
CertifiedPublicSubkey cpsKey = (CertifiedPublicSubkey)ieSubkeys.Current;
// The subkey has been revoced
if (cpsKey.RevocationSignature != null)
continue;
PublicKeyPacket pkpKey = cpsKey.Subkey;
if (aaAction == AsymActions.Encrypt) {
if (pkpKey.Algorithm == AsymAlgorithms.ElGama_Encrypt_Sign ||
pkpKey.Algorithm == AsymAlgorithms.ElGamal_Encrypt_Only ||
pkpKey.Algorithm == AsymAlgorithms.RSA_Encrypt_Only ||
pkpKey.Algorithm == AsymAlgorithms.RSA_Encrypt_Sign) {
if ((bFound && dtCandidateTime < pkpKey.TimeCreated) || (!bFound)) {
dtCandidateTime = pkpKey.TimeCreated;
bFound = true;
pkpCandidate = pkpKey;
}
}
} else if (aaAction == AsymActions.Sign) {
if (pkpKey.Algorithm == AsymAlgorithms.ElGama_Encrypt_Sign ||
pkpKey.Algorithm == AsymAlgorithms.DSA ||
pkpKey.Algorithm == AsymAlgorithms.RSA_Sign_Only ||
pkpKey.Algorithm == AsymAlgorithms.RSA_Encrypt_Sign) {
if ((bFound && dtCandidateTime < pkpKey.TimeCreated) || (!bFound)) {
dtCandidateTime = pkpKey.TimeCreated;
bFound = true;
pkpCandidate = pkpKey;
}
}
}
}
if (bFound)
return pkpCandidate;
return null;
}
/// <summary>
/// Returns true if the given object is the "this" key.
/// </summary>
/// <remarks>
/// The keys are compared by there fingerprint. If the fingerprint
/// is the same, the keys are said to be the same.
/// </remarks>
/// <param name="o">An object that shall be compared against
/// this.</param>
/// <returns>True if the giben object o is the same as the
/// "this" key.</returns>
public override bool Equals(object o) {
if (o is TransportablePublicKey) {
TransportablePublicKey tpkKey = (TransportablePublicKey)o;
return (tpkKey.PrimaryKey.Fingerprint == this.PrimaryKey.Fingerprint);
}
return false;
}
public override int GetHashCode() {
return (int)(this.PrimaryKey.KeyID & 0xFFFFFFFF);
}
/// <summary>
/// Parses the radix64 encoded representation of a transportable public
/// key given as an argument to populate the parameters of this.
/// </summary>
/// <remarks>No remarks</remarks>
/// <param name="strRadix64">Radix64 representation of an transportable
/// public key</param>
/// <exception cref="System.ArgumentException">Throws an
/// ArgumentException if the radix64 string given as a parameter is
/// not an transportable public key.</exception>
public void Parse(string strRadix64) {
Packet[] pPackets = Packet.ParsePackets(strRadix64);
int nCurrentPacket = 0;
int nUserIDCounter = 0;
try {
// First we expect a PublicKeyPacket
if (!(pPackets[0] is PublicKeyPacket)) {
throw(new ArgumentException("The given packet is not in the required transportable public key format!"));
}
this.PrimaryKey = (PublicKeyPacket)pPackets[nCurrentPacket++];
// Next we expect zero or more revocation signatures
while ((nCurrentPacket < pPackets.Length) && (pPackets[nCurrentPacket] is SignaturePacket)) {
SignaturePacket spRevocation = (SignaturePacket)pPackets[nCurrentPacket++];
if (spRevocation.SignatureType != SignatureTypes.KeyRevocationSignature) {
throw(new ArgumentException("The given packet is not in the required transportable public key format!"));
}
this.RevocationSignatures.Add(spRevocation);
}
// Next in queue must be one or more UserID Packets
while ((nCurrentPacket < pPackets.Length) && (pPackets[nCurrentPacket] is UserIDPacket)) {
nUserIDCounter++;
CertifiedUserID cuiUserID = new CertifiedUserID();
UserIDPacket uipUserID = (UserIDPacket)pPackets[nCurrentPacket++];
cuiUserID.UserID = uipUserID;
// For every UserIDPacket we expect zero or more Signatures (Certificates)
while ((nCurrentPacket < pPackets.Length) && (pPackets[nCurrentPacket] is SignaturePacket)) {
SignaturePacket spCertificate = (SignaturePacket)pPackets[nCurrentPacket++];
if ((spCertificate.SignatureType != SignatureTypes.UserIDSignature) &&
(spCertificate.SignatureType != SignatureTypes.UserIDSignature_CasualVerification) &&
(spCertificate.SignatureType != SignatureTypes.UserIDSignature_NoVerification) &&
(spCertificate.SignatureType != SignatureTypes.UserIDSignature_PositivVerification)) {
throw(new ArgumentException("The given packet is not in the required transportable public key format!"));
}
cuiUserID.Certificates.Add(spCertificate);
}
this.Certifications.Add(cuiUserID);
}
// There was no UserIDPacket. This is fatal!!!
if (nUserIDCounter == 0) {
throw(new ArgumentException("The given packet is not in the required transportable public key format!"));
}
// Finally we have zero or more subkeys
while ((nCurrentPacket < pPackets.Length) && (pPackets[nCurrentPacket] is PublicKeyPacket)) {
PublicKeyPacket pkpSubKey = (PublicKeyPacket)pPackets[nCurrentPacket++];
CertifiedPublicSubkey cpsSubKey = new CertifiedPublicSubkey();
cpsSubKey.Subkey = pkpSubKey;
if ((nCurrentPacket < pPackets.Length) && (pPackets[nCurrentPacket] is SignaturePacket)) {
SignaturePacket spKeySignature = (SignaturePacket)pPackets[nCurrentPacket++];
if (spKeySignature.SignatureType == SignatureTypes.SubkeyBindingSignature) {
cpsSubKey.KeyBindingSignature = spKeySignature;
} else if (spKeySignature.SignatureType == SignatureTypes.SubkeyRevocationSignature) {
cpsSubKey.RevocationSignature = spKeySignature;
}
} else {
throw(new ArgumentException("The given packet is not in the required transportable public key format!"));
}
if (nCurrentPacket < pPackets.Length) {
if (pPackets[nCurrentPacket] is SignaturePacket) {
SignaturePacket spSubkeyRev = (SignaturePacket)pPackets[nCurrentPacket++];
cpsSubKey.RevocationSignature = spSubkeyRev;
}
}
this.SubKeys.Add(cpsSubKey);
}
} catch (System.IndexOutOfRangeException) {
if (nUserIDCounter == 0) {
throw(new ArgumentException("The given packet is not in the required transportable public key format!"));
}
}
}
private DateTime FindExpirationDate() {
IEnumerator ieCertificates = this.alCertifications.GetEnumerator();
while (ieCertificates.MoveNext()) {
if (!(ieCertificates.Current is CertifiedUserID))
continue;
CertifiedUserID cuiID = (CertifiedUserID)ieCertificates.Current;
IEnumerator ieSignatures = cuiID.Certificates.GetEnumerator();
while (ieSignatures.MoveNext()) {
if (!(ieSignatures.Current is SignaturePacket))
continue;
SignaturePacket spCertificate = (SignaturePacket)ieSignatures.Current;
// look only at selfsignatures
if (spCertificate.KeyID != this.PrimaryKey.KeyID)
continue;
for (int i=0; i<spCertificate.HashedSubPackets.Length; i++) {
if (spCertificate.HashedSubPackets[i].Type == SignatureSubPacketTypes.KeyExpirationTime) {
return spCertificate.HashedSubPackets[i].KeyExpirationTime;
}
}
}
}
throw new Exception("never");
}
public SymAlgorithms[] FindPreferedAlgorithms() {
IEnumerator ieCertificates = this.alCertifications.GetEnumerator();
while (ieCertificates.MoveNext()) {
if (!(ieCertificates.Current is CertifiedUserID))
continue;
CertifiedUserID cuiID = (CertifiedUserID)ieCertificates.Current;
IEnumerator ieSignatures = cuiID.Certificates.GetEnumerator();
while (ieSignatures.MoveNext()) {
if (!(ieSignatures.Current is SignaturePacket))
continue;
SignaturePacket spCertificate = (SignaturePacket)ieSignatures.Current;
// look only at selfsignatures
if (spCertificate.KeyID != this.PrimaryKey.KeyID)
continue;
try {
SymAlgorithms[] saReturn = spCertificate.FindPreferedSymAlgorithms();
return saReturn;
} catch (Exception) {}
}
}
throw new Exception("none found!");
}
private string FindPrimaryUserID() {
string strReturn = "";
int nUserIDCounter = 0;
IEnumerator ieCertificates = this.alCertifications.GetEnumerator();
while (ieCertificates.MoveNext()) {
if (!(ieCertificates.Current is CertifiedUserID))
continue;
nUserIDCounter++;
CertifiedUserID cuiID = (CertifiedUserID)ieCertificates.Current;
IEnumerator ieSignatures = cuiID.Certificates.GetEnumerator();
while (ieSignatures.MoveNext()) {
if (!(ieSignatures.Current is SignaturePacket))
continue;
SignaturePacket spCertificate = (SignaturePacket)ieSignatures.Current;
// look only at selfsignatures
if (spCertificate.KeyID != this.PrimaryKey.KeyID)
continue;
if (nUserIDCounter == 1) {
strReturn = cuiID.UserID.UserID;
}
for (int i=0; i<spCertificate.UnhashedSubPackets.Length; i++) {
if ((spCertificate.UnhashedSubPackets[i].Type == SignatureSubPacketTypes.PrimaryUserID) && (spCertificate.UnhashedSubPackets[i].PrimaryUserID)) {
strReturn = cuiID.UserID.UserID;
}
}
for (int i=0; i<spCertificate.HashedSubPackets.Length; i++) {
if ((spCertificate.HashedSubPackets[i].Type == SignatureSubPacketTypes.PrimaryUserID) && (spCertificate.HashedSubPackets[i].PrimaryUserID)) {
strReturn = cuiID.UserID.UserID;
}
}
}
}
return strReturn;
}
public static TransportablePublicKey[] SplitKeys(string strRadix64) {
ArrayList alKeys = new ArrayList();
Packet[] pPackets = Packet.ParsePackets(strRadix64);
byte[] bOneKey = new byte[0];
for (int i=0; i<pPackets.Length; i++) {
if (pPackets[i] is PublicKeyPacket) {
PublicKeyPacket pkpKey = (PublicKeyPacket)pPackets[i];
if ((pkpKey.Content == ContentTypes.PublicKey) && (bOneKey.Length > 10)) {
TransportablePublicKey tpkKey = new TransportablePublicKey(Radix64.Encode(bOneKey, true));
alKeys.Add(tpkKey);
bOneKey = new byte[0];
}
}
byte[] bPacket = pPackets[i].Generate();
byte[] bTmpKey = new byte[bOneKey.Length];
bOneKey.CopyTo(bTmpKey, 0);
bOneKey = new byte[bOneKey.Length + bPacket.Length];
Array.Copy(bTmpKey, 0, bOneKey, 0, bTmpKey.Length);
Array.Copy(bPacket, 0, bOneKey, bTmpKey.Length, bPacket.Length);
}
if (bOneKey.Length > 10) {
TransportablePublicKey tpkKey = new TransportablePublicKey(Radix64.Encode(bOneKey, true));
alKeys.Add(tpkKey);
}
TransportablePublicKey[] tpkKeys = new TransportablePublicKey[alKeys.Count];
int iCount = 0;
IEnumerator ieKeys = alKeys.GetEnumerator();
while (ieKeys.MoveNext()) {
if (!(ieKeys.Current is TransportablePublicKey))
continue;
tpkKeys[iCount++] = (TransportablePublicKey)ieKeys.Current;
}
return tpkKeys;
}
}
}
Submit an article or tip