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package sun.security.pkcs11;

import java.io.IOException;
import java.math.BigInteger;
import java.nio.ByteBuffer;

import java.security.*;
import java.security.interfaces.*;
import java.security.spec.AlgorithmParameterSpec;
import sun.nio.ch.DirectBuffer;

import sun.security.util.*;
import sun.security.x509.AlgorithmId;

import sun.security.rsa.RSASignature;
import sun.security.rsa.RSAPadding;

import sun.security.pkcs11.wrapper.*;
import static sun.security.pkcs11.wrapper.PKCS11Constants.*;
import sun.security.util.KeyUtil;

Signature implementation class. This class currently supports the following algorithms: . DSA . NONEwithDSA (RawDSA) . SHA1withDSA . NONEwithDSAinP1363Format (RawDSAinP1363Format) . SHA1withDSAinP1363Format . RSA: . MD2withRSA . MD5withRSA . SHA1withRSA . SHA224withRSA . SHA256withRSA . SHA384withRSA . SHA512withRSA . ECDSA . NONEwithECDSA . SHA1withECDSA . SHA224withECDSA . SHA256withECDSA . SHA384withECDSA . SHA512withECDSA . NONEwithECDSAinP1363Format . SHA1withECDSAinP1363Format . SHA224withECDSAinP1363Format . SHA256withECDSAinP1363Format . SHA384withECDSAinP1363Format . SHA512withECDSAinP1363Format Note that the underlying PKCS#11 token may support complete signature algorithm (e.g. CKM_DSA_SHA1, CKM_MD5_RSA_PKCS), or it may just implement the signature algorithm without hashing (e.g. CKM_DSA, CKM_PKCS), or it may only implement the raw public key operation (CKM_RSA_X_509). This class uses what is available and adds whatever extra processing is needed.
Author: Andreas Sterbenz
Since: 1.5
/** * Signature implementation class. This class currently supports the * following algorithms: * * . DSA * . NONEwithDSA (RawDSA) * . SHA1withDSA * . NONEwithDSAinP1363Format (RawDSAinP1363Format) * . SHA1withDSAinP1363Format * . RSA: * . MD2withRSA * . MD5withRSA * . SHA1withRSA * . SHA224withRSA * . SHA256withRSA * . SHA384withRSA * . SHA512withRSA * . ECDSA * . NONEwithECDSA * . SHA1withECDSA * . SHA224withECDSA * . SHA256withECDSA * . SHA384withECDSA * . SHA512withECDSA * . NONEwithECDSAinP1363Format * . SHA1withECDSAinP1363Format * . SHA224withECDSAinP1363Format * . SHA256withECDSAinP1363Format * . SHA384withECDSAinP1363Format * . SHA512withECDSAinP1363Format * * Note that the underlying PKCS#11 token may support complete signature * algorithm (e.g. CKM_DSA_SHA1, CKM_MD5_RSA_PKCS), or it may just * implement the signature algorithm without hashing (e.g. CKM_DSA, CKM_PKCS), * or it may only implement the raw public key operation (CKM_RSA_X_509). * This class uses what is available and adds whatever extra processing * is needed. * * @author Andreas Sterbenz * @since 1.5 */
final class P11Signature extends SignatureSpi { // token instance private final Token token; // algorithm name private final String algorithm; // name of the key algorithm, currently either RSA or DSA private final String keyAlgorithm; // mechanism id private final long mechanism; // digest algorithm OID, if we encode RSA signature ourselves private final ObjectIdentifier digestOID; // type, one of T_* below private final int type; // key instance used, if init*() was called private P11Key p11Key; // message digest, if we do the digesting ourselves private final MessageDigest md; // associated session, if any private Session session; // mode, one of M_* below private int mode; // flag indicating whether an operation is initialized private boolean initialized; // buffer, for update(byte) or DSA private final byte[] buffer; // total number of bytes processed in current operation private int bytesProcessed; // The format, to be used for DSA and ECDSA signatures. // If true, the IEEE P1363 format will be used, the concatenation of // r and s. If false (default), the signature will be formatted as a // DER-encoded ASN.1 sequence of r and s. private boolean p1363Format = false; // constant for signing mode private final static int M_SIGN = 1; // constant for verification mode private final static int M_VERIFY = 2; // constant for type digesting, we do the hashing ourselves private final static int T_DIGEST = 1; // constant for type update, token does everything private final static int T_UPDATE = 2; // constant for type raw, used with RawDSA and NONEwithECDSA only private final static int T_RAW = 3; // XXX PKCS#11 v2.20 says "should not be longer than 1024 bits", // but this is a little arbitrary private final static int RAW_ECDSA_MAX = 128; P11Signature(Token token, String algorithm, long mechanism) throws NoSuchAlgorithmException, PKCS11Exception { super(); this.token = token; this.algorithm = algorithm; this.mechanism = mechanism; byte[] buffer = null; ObjectIdentifier digestOID = null; MessageDigest md = null; switch ((int)mechanism) { case (int)CKM_MD2_RSA_PKCS: case (int)CKM_MD5_RSA_PKCS: case (int)CKM_SHA1_RSA_PKCS: case (int)CKM_SHA224_RSA_PKCS: case (int)CKM_SHA256_RSA_PKCS: case (int)CKM_SHA384_RSA_PKCS: case (int)CKM_SHA512_RSA_PKCS: keyAlgorithm = "RSA"; type = T_UPDATE; buffer = new byte[1]; break; case (int)CKM_DSA_SHA1: keyAlgorithm = "DSA"; type = T_UPDATE; buffer = new byte[1]; break; case (int)CKM_ECDSA_SHA1: keyAlgorithm = "EC"; type = T_UPDATE; buffer = new byte[1]; break; case (int)CKM_DSA: keyAlgorithm = "DSA"; if (algorithm.equals("DSA") || algorithm.equals("DSAinP1363Format")) { type = T_DIGEST; md = MessageDigest.getInstance("SHA-1"); } else if (algorithm.equals("RawDSA") || algorithm.equals("RawDSAinP1363Format")) { type = T_RAW; buffer = new byte[20]; } else { throw new ProviderException(algorithm); } break; case (int)CKM_ECDSA: keyAlgorithm = "EC"; if (algorithm.equals("NONEwithECDSA") || algorithm.equals("NONEwithECDSAinP1363Format")) { type = T_RAW; buffer = new byte[RAW_ECDSA_MAX]; } else { String digestAlg; if (algorithm.equals("SHA1withECDSA") || algorithm.equals("SHA1withECDSAinP1363Format")) { digestAlg = "SHA-1"; } else if (algorithm.equals("SHA224withECDSA") || algorithm.equals("SHA224withECDSAinP1363Format")) { digestAlg = "SHA-224"; } else if (algorithm.equals("SHA256withECDSA") || algorithm.equals("SHA256withECDSAinP1363Format")) { digestAlg = "SHA-256"; } else if (algorithm.equals("SHA384withECDSA") || algorithm.equals("SHA384withECDSAinP1363Format")) { digestAlg = "SHA-384"; } else if (algorithm.equals("SHA512withECDSA") || algorithm.equals("SHA512withECDSAinP1363Format")) { digestAlg = "SHA-512"; } else { throw new ProviderException(algorithm); } type = T_DIGEST; md = MessageDigest.getInstance(digestAlg); } break; case (int)CKM_RSA_PKCS: case (int)CKM_RSA_X_509: keyAlgorithm = "RSA"; type = T_DIGEST; if (algorithm.equals("MD5withRSA")) { md = MessageDigest.getInstance("MD5"); digestOID = AlgorithmId.MD5_oid; } else if (algorithm.equals("SHA1withRSA")) { md = MessageDigest.getInstance("SHA-1"); digestOID = AlgorithmId.SHA_oid; } else if (algorithm.equals("MD2withRSA")) { md = MessageDigest.getInstance("MD2"); digestOID = AlgorithmId.MD2_oid; } else if (algorithm.equals("SHA224withRSA")) { md = MessageDigest.getInstance("SHA-224"); digestOID = AlgorithmId.SHA224_oid; } else if (algorithm.equals("SHA256withRSA")) { md = MessageDigest.getInstance("SHA-256"); digestOID = AlgorithmId.SHA256_oid; } else if (algorithm.equals("SHA384withRSA")) { md = MessageDigest.getInstance("SHA-384"); digestOID = AlgorithmId.SHA384_oid; } else if (algorithm.equals("SHA512withRSA")) { md = MessageDigest.getInstance("SHA-512"); digestOID = AlgorithmId.SHA512_oid; } else { throw new ProviderException("Unknown signature: " + algorithm); } break; default: throw new ProviderException("Unknown mechanism: " + mechanism); } this.buffer = buffer; this.digestOID = digestOID; this.md = md; if (algorithm.endsWith("inP1363Format")) { this.p1363Format = true; } } private void ensureInitialized() { token.ensureValid(); if (initialized == false) { initialize(); } } private void cancelOperation() { token.ensureValid(); if (initialized == false) { return; } initialized = false; if ((session == null) || (token.explicitCancel == false)) { return; } if (session.hasObjects() == false) { session = token.killSession(session); return; } try { // "cancel" operation by finishing it // XXX make sure all this always works correctly if (mode == M_SIGN) { try { if (type == T_UPDATE) { token.p11.C_SignFinal(session.id(), 0); } else { byte[] digest; if (type == T_DIGEST) { digest = md.digest(); } else { // T_RAW digest = buffer; } token.p11.C_Sign(session.id(), digest); } } catch (PKCS11Exception e) { throw new ProviderException("cancel failed", e); } } else { // M_VERIFY try { byte[] signature; if (keyAlgorithm.equals("DSA")) { signature = new byte[40]; } else { signature = new byte[(p11Key.length() + 7) >> 3]; } if (type == T_UPDATE) { token.p11.C_VerifyFinal(session.id(), signature); } else { byte[] digest; if (type == T_DIGEST) { digest = md.digest(); } else { // T_RAW digest = buffer; } token.p11.C_Verify(session.id(), digest, signature); } } catch (PKCS11Exception e) { // will fail since the signature is incorrect // XXX check error code } } } finally { session = token.releaseSession(session); } } // assumes current state is initialized == false private void initialize() { try { if (session == null) { session = token.getOpSession(); } if (mode == M_SIGN) { token.p11.C_SignInit(session.id(), new CK_MECHANISM(mechanism), p11Key.keyID); } else { token.p11.C_VerifyInit(session.id(), new CK_MECHANISM(mechanism), p11Key.keyID); } initialized = true; } catch (PKCS11Exception e) { // release session when initialization failed session = token.releaseSession(session); throw new ProviderException("Initialization failed", e); } if (bytesProcessed != 0) { bytesProcessed = 0; if (md != null) { md.reset(); } } } private void checkKeySize(String keyAlgo, Key key) throws InvalidKeyException { CK_MECHANISM_INFO mechInfo = null; try { mechInfo = token.getMechanismInfo(mechanism); } catch (PKCS11Exception e) { // should not happen, ignore for now. } if (mechInfo == null) { // skip the check if no native info available return; } int minKeySize = (int) mechInfo.ulMinKeySize; int maxKeySize = (int) mechInfo.ulMaxKeySize; // need to override the MAX keysize for SHA1withDSA if (md != null && mechanism == CKM_DSA && maxKeySize > 1024) { maxKeySize = 1024; } int keySize = 0; if (key instanceof P11Key) { keySize = ((P11Key) key).length(); } else { try { if (keyAlgo.equals("RSA")) { keySize = ((RSAKey) key).getModulus().bitLength(); } else if (keyAlgo.equals("DSA")) { keySize = ((DSAKey) key).getParams().getP().bitLength(); } else if (keyAlgo.equals("EC")) { keySize = ((ECKey) key).getParams().getCurve().getField().getFieldSize(); } else { throw new ProviderException("Error: unsupported algo " + keyAlgo); } } catch (ClassCastException cce) { throw new InvalidKeyException(keyAlgo + " key must be the right type", cce); } } if ((minKeySize != -1) && (keySize < minKeySize)) { throw new InvalidKeyException(keyAlgo + " key must be at least " + minKeySize + " bits"); } if ((maxKeySize != -1) && (keySize > maxKeySize)) { throw new InvalidKeyException(keyAlgo + " key must be at most " + maxKeySize + " bits"); } if (keyAlgo.equals("RSA")) { checkRSAKeyLength(keySize); } } private void checkRSAKeyLength(int len) throws InvalidKeyException { RSAPadding padding; try { padding = RSAPadding.getInstance (RSAPadding.PAD_BLOCKTYPE_1, (len + 7) >> 3); } catch (InvalidAlgorithmParameterException iape) { throw new InvalidKeyException(iape.getMessage()); } int maxDataSize = padding.getMaxDataSize(); int encodedLength; if (algorithm.equals("MD5withRSA") || algorithm.equals("MD2withRSA")) { encodedLength = 34; } else if (algorithm.equals("SHA1withRSA")) { encodedLength = 35; } else if (algorithm.equals("SHA224withRSA")) { encodedLength = 47; } else if (algorithm.equals("SHA256withRSA")) { encodedLength = 51; } else if (algorithm.equals("SHA384withRSA")) { encodedLength = 67; } else if (algorithm.equals("SHA512withRSA")) { encodedLength = 83; } else { throw new ProviderException("Unknown signature algo: " + algorithm); } if (encodedLength > maxDataSize) { throw new InvalidKeyException ("Key is too short for this signature algorithm"); } } // see JCA spec @Override protected void engineInitVerify(PublicKey publicKey) throws InvalidKeyException { if (publicKey == null) { throw new InvalidKeyException("Key must not be null"); } // Need to check key length whenever a new key is set if (publicKey != p11Key) { checkKeySize(keyAlgorithm, publicKey); } cancelOperation(); mode = M_VERIFY; p11Key = P11KeyFactory.convertKey(token, publicKey, keyAlgorithm); initialize(); } // see JCA spec @Override protected void engineInitSign(PrivateKey privateKey) throws InvalidKeyException { if (privateKey == null) { throw new InvalidKeyException("Key must not be null"); } // Need to check RSA key length whenever a new key is set if (privateKey != p11Key) { checkKeySize(keyAlgorithm, privateKey); } cancelOperation(); mode = M_SIGN; p11Key = P11KeyFactory.convertKey(token, privateKey, keyAlgorithm); initialize(); } // see JCA spec @Override protected void engineUpdate(byte b) throws SignatureException { ensureInitialized(); switch (type) { case T_UPDATE: buffer[0] = b; engineUpdate(buffer, 0, 1); break; case T_DIGEST: md.update(b); bytesProcessed++; break; case T_RAW: if (bytesProcessed >= buffer.length) { bytesProcessed = buffer.length + 1; return; } buffer[bytesProcessed++] = b; break; default: throw new ProviderException("Internal error"); } } // see JCA spec @Override protected void engineUpdate(byte[] b, int ofs, int len) throws SignatureException { ensureInitialized(); if (len == 0) { return; } // check for overflow if (len + bytesProcessed < 0) { throw new ProviderException("Processed bytes limits exceeded."); } switch (type) { case T_UPDATE: try { if (mode == M_SIGN) { token.p11.C_SignUpdate(session.id(), 0, b, ofs, len); } else { token.p11.C_VerifyUpdate(session.id(), 0, b, ofs, len); } bytesProcessed += len; } catch (PKCS11Exception e) { initialized = false; session = token.releaseSession(session); throw new ProviderException(e); } break; case T_DIGEST: md.update(b, ofs, len); bytesProcessed += len; break; case T_RAW: if (bytesProcessed + len > buffer.length) { bytesProcessed = buffer.length + 1; return; } System.arraycopy(b, ofs, buffer, bytesProcessed, len); bytesProcessed += len; break; default: throw new ProviderException("Internal error"); } } // see JCA spec @Override protected void engineUpdate(ByteBuffer byteBuffer) { ensureInitialized(); int len = byteBuffer.remaining(); if (len <= 0) { return; } switch (type) { case T_UPDATE: if (byteBuffer instanceof DirectBuffer == false) { // cannot do better than default impl super.engineUpdate(byteBuffer); return; } long addr = ((DirectBuffer)byteBuffer).address(); int ofs = byteBuffer.position(); try { if (mode == M_SIGN) { token.p11.C_SignUpdate (session.id(), addr + ofs, null, 0, len); } else { token.p11.C_VerifyUpdate (session.id(), addr + ofs, null, 0, len); } bytesProcessed += len; byteBuffer.position(ofs + len); } catch (PKCS11Exception e) { initialized = false; session = token.releaseSession(session); throw new ProviderException("Update failed", e); } break; case T_DIGEST: md.update(byteBuffer); bytesProcessed += len; break; case T_RAW: if (bytesProcessed + len > buffer.length) { bytesProcessed = buffer.length + 1; return; } byteBuffer.get(buffer, bytesProcessed, len); bytesProcessed += len; break; default: throw new ProviderException("Internal error"); } } // see JCA spec @Override protected byte[] engineSign() throws SignatureException { ensureInitialized(); try { byte[] signature; if (type == T_UPDATE) { int len = keyAlgorithm.equals("DSA") ? 40 : 0; signature = token.p11.C_SignFinal(session.id(), len); } else { byte[] digest; if (type == T_DIGEST) { digest = md.digest(); } else { // T_RAW if (mechanism == CKM_DSA) { if (bytesProcessed != buffer.length) { throw new SignatureException ("Data for RawDSA must be exactly 20 bytes long"); } digest = buffer; } else { // CKM_ECDSA if (bytesProcessed > buffer.length) { throw new SignatureException("Data for NONEwithECDSA" + " must be at most " + RAW_ECDSA_MAX + " bytes long"); } digest = new byte[bytesProcessed]; System.arraycopy(buffer, 0, digest, 0, bytesProcessed); } } if (keyAlgorithm.equals("RSA") == false) { // DSA and ECDSA signature = token.p11.C_Sign(session.id(), digest); } else { // RSA byte[] data = encodeSignature(digest); if (mechanism == CKM_RSA_X_509) { data = pkcs1Pad(data); } signature = token.p11.C_Sign(session.id(), data); } } if (keyAlgorithm.equals("RSA")) { return signature; } else { if (p1363Format) { return signature; } else { return dsaToASN1(signature); } } } catch (PKCS11Exception pe) { throw new ProviderException(pe); } catch (SignatureException | ProviderException e) { cancelOperation(); throw e; } finally { initialized = false; session = token.releaseSession(session); } } // see JCA spec @Override protected boolean engineVerify(byte[] signature) throws SignatureException { ensureInitialized(); try { if (!p1363Format) { if (keyAlgorithm.equals("DSA")) { signature = asn1ToDSA(signature); } else if (keyAlgorithm.equals("EC")) { signature = asn1ToECDSA(signature); } } if (type == T_UPDATE) { token.p11.C_VerifyFinal(session.id(), signature); } else { byte[] digest; if (type == T_DIGEST) { digest = md.digest(); } else { // T_RAW if (mechanism == CKM_DSA) { if (bytesProcessed != buffer.length) { throw new SignatureException ("Data for RawDSA must be exactly 20 bytes long"); } digest = buffer; } else { if (bytesProcessed > buffer.length) { throw new SignatureException("Data for NONEwithECDSA" + " must be at most " + RAW_ECDSA_MAX + " bytes long"); } digest = new byte[bytesProcessed]; System.arraycopy(buffer, 0, digest, 0, bytesProcessed); } } if (keyAlgorithm.equals("RSA") == false) { // DSA and ECDSA token.p11.C_Verify(session.id(), digest, signature); } else { // RSA byte[] data = encodeSignature(digest); if (mechanism == CKM_RSA_X_509) { data = pkcs1Pad(data); } token.p11.C_Verify(session.id(), data, signature); } } return true; } catch (PKCS11Exception pe) { long errorCode = pe.getErrorCode(); if (errorCode == CKR_SIGNATURE_INVALID) { return false; } if (errorCode == CKR_SIGNATURE_LEN_RANGE) { // return false rather than throwing an exception return false; } // ECF bug? if (errorCode == CKR_DATA_LEN_RANGE) { return false; } throw new ProviderException(pe); } catch (SignatureException | ProviderException e) { cancelOperation(); throw e; } finally { initialized = false; session = token.releaseSession(session); } } private byte[] pkcs1Pad(byte[] data) { try { int len = (p11Key.length() + 7) >> 3; RSAPadding padding = RSAPadding.getInstance (RSAPadding.PAD_BLOCKTYPE_1, len); byte[] padded = padding.pad(data); return padded; } catch (GeneralSecurityException e) { throw new ProviderException(e); } } private byte[] encodeSignature(byte[] digest) throws SignatureException { try { return RSASignature.encodeSignature(digestOID, digest); } catch (IOException e) { throw new SignatureException("Invalid encoding", e); } } // private static byte[] decodeSignature(byte[] signature) throws IOException { // return RSASignature.decodeSignature(digestOID, signature); // } // For DSA and ECDSA signatures, PKCS#11 represents them as a simple // byte array that contains the concatenation of r and s. // For DSA, r and s are always exactly 20 bytes long. // For ECDSA, r and s are of variable length, but we know that each // occupies half of the array. private static byte[] dsaToASN1(byte[] signature) { int n = signature.length >> 1; BigInteger r = new BigInteger(1, P11Util.subarray(signature, 0, n)); BigInteger s = new BigInteger(1, P11Util.subarray(signature, n, n)); try { DerOutputStream outseq = new DerOutputStream(100); outseq.putInteger(r); outseq.putInteger(s); DerValue result = new DerValue(DerValue.tag_Sequence, outseq.toByteArray()); return result.toByteArray(); } catch (java.io.IOException e) { throw new RuntimeException("Internal error", e); } } private static byte[] asn1ToDSA(byte[] sig) throws SignatureException { try { // Enforce strict DER checking for signatures DerInputStream in = new DerInputStream(sig, 0, sig.length, false); DerValue[] values = in.getSequence(2); // check number of components in the read sequence // and trailing data if ((values.length != 2) || (in.available() != 0)) { throw new IOException("Invalid encoding for signature"); } BigInteger r = values[0].getPositiveBigInteger(); BigInteger s = values[1].getPositiveBigInteger(); byte[] br = toByteArray(r, 20); byte[] bs = toByteArray(s, 20); if ((br == null) || (bs == null)) { throw new SignatureException("Out of range value for R or S"); } return P11Util.concat(br, bs); } catch (SignatureException e) { throw e; } catch (Exception e) { throw new SignatureException("Invalid encoding for signature", e); } } private byte[] asn1ToECDSA(byte[] sig) throws SignatureException { try { // Enforce strict DER checking for signatures DerInputStream in = new DerInputStream(sig, 0, sig.length, false); DerValue[] values = in.getSequence(2); // check number of components in the read sequence // and trailing data if ((values.length != 2) || (in.available() != 0)) { throw new IOException("Invalid encoding for signature"); } BigInteger r = values[0].getPositiveBigInteger(); BigInteger s = values[1].getPositiveBigInteger(); // trim leading zeroes byte[] br = KeyUtil.trimZeroes(r.toByteArray()); byte[] bs = KeyUtil.trimZeroes(s.toByteArray()); int k = Math.max(br.length, bs.length); // r and s each occupy half the array byte[] res = new byte[k << 1]; System.arraycopy(br, 0, res, k - br.length, br.length); System.arraycopy(bs, 0, res, res.length - bs.length, bs.length); return res; } catch (Exception e) { throw new SignatureException("Invalid encoding for signature", e); } } private static byte[] toByteArray(BigInteger bi, int len) { byte[] b = bi.toByteArray(); int n = b.length; if (n == len) { return b; } if ((n == len + 1) && (b[0] == 0)) { byte[] t = new byte[len]; System.arraycopy(b, 1, t, 0, len); return t; } if (n > len) { return null; } // must be smaller byte[] t = new byte[len]; System.arraycopy(b, 0, t, (len - n), n); return t; } // see JCA spec @SuppressWarnings("deprecation") @Override protected void engineSetParameter(String param, Object value) throws InvalidParameterException { throw new UnsupportedOperationException("setParameter() not supported"); } // see JCA spec @Override protected void engineSetParameter(AlgorithmParameterSpec params) throws InvalidAlgorithmParameterException { if (params != null) { throw new InvalidAlgorithmParameterException("No parameter accepted"); } } // see JCA spec @SuppressWarnings("deprecation") @Override protected Object engineGetParameter(String param) throws InvalidParameterException { throw new UnsupportedOperationException("getParameter() not supported"); } // see JCA spec @Override protected AlgorithmParameters engineGetParameters() { return null; } }