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package org.bouncycastle.crypto.test;
import java.math.BigInteger;
import java.security.SecureRandom;
import org.bouncycastle.crypto.CryptoException;
import org.bouncycastle.crypto.agreement.srp.SRP6Client;
import org.bouncycastle.crypto.agreement.srp.SRP6Server;
import org.bouncycastle.crypto.agreement.srp.SRP6StandardGroups;
import org.bouncycastle.crypto.agreement.srp.SRP6Util;
import org.bouncycastle.crypto.agreement.srp.SRP6VerifierGenerator;
import org.bouncycastle.crypto.digests.SHA1Digest;
import org.bouncycastle.crypto.digests.SHA256Digest;
import org.bouncycastle.crypto.generators.DHParametersGenerator;
import org.bouncycastle.crypto.params.DHParameters;
import org.bouncycastle.crypto.params.SRP6GroupParameters;
import org.bouncycastle.util.encoders.Hex;
import org.bouncycastle.util.test.SimpleTest;
public class SRP6Test extends SimpleTest
{
private static final BigInteger ZERO = BigInteger.valueOf(0);
private static BigInteger fromHex(String hex)
{
return new BigInteger(1, Hex.decode(hex));
}
private final SecureRandom random = new SecureRandom();
public String getName()
{
return "SRP6";
}
public void performTest() throws Exception
{
rfc5054AppendixBTestVectors();
testMutualVerification(SRP6StandardGroups.rfc5054_1024);
testClientCatchesBadB(SRP6StandardGroups.rfc5054_1024);
testServerCatchesBadA(SRP6StandardGroups.rfc5054_1024);
testWithRandomParams(256);
testWithRandomParams(384);
testWithRandomParams(512);
}
private void rfc5054AppendixBTestVectors() throws Exception
{
byte[] I = "alice".getBytes("UTF8");
byte[] P = "password123".getBytes("UTF8");
byte[] s = Hex.decode("BEB25379D1A8581EB5A727673A2441EE");
BigInteger N = SRP6StandardGroups.rfc5054_1024.getN();
BigInteger g = SRP6StandardGroups.rfc5054_1024.getG();
BigInteger a = fromHex("60975527035CF2AD1989806F0407210BC81EDC04E2762A56AFD529DDDA2D4393");
BigInteger b = fromHex("E487CB59D31AC550471E81F00F6928E01DDA08E974A004F49E61F5D105284D20");
BigInteger expect_k = fromHex("7556AA045AEF2CDD07ABAF0F665C3E818913186F");
BigInteger expect_x = fromHex("94B7555AABE9127CC58CCF4993DB6CF84D16C124");
BigInteger expect_v = fromHex("7E273DE8696FFC4F4E337D05B4B375BEB0DDE1569E8FA00A9886D812"
+ "9BADA1F1822223CA1A605B530E379BA4729FDC59F105B4787E5186F5"
+ "C671085A1447B52A48CF1970B4FB6F8400BBF4CEBFBB168152E08AB5"
+ "EA53D15C1AFF87B2B9DA6E04E058AD51CC72BFC9033B564E26480D78"
+ "E955A5E29E7AB245DB2BE315E2099AFB");
BigInteger expect_A = fromHex("61D5E490F6F1B79547B0704C436F523DD0E560F0C64115BB72557EC4"
+ "4352E8903211C04692272D8B2D1A5358A2CF1B6E0BFCF99F921530EC"
+ "8E39356179EAE45E42BA92AEACED825171E1E8B9AF6D9C03E1327F44"
+ "BE087EF06530E69F66615261EEF54073CA11CF5858F0EDFDFE15EFEA"
+ "B349EF5D76988A3672FAC47B0769447B");
BigInteger expect_B = fromHex("BD0C61512C692C0CB6D041FA01BB152D4916A1E77AF46AE105393011"
+ "BAF38964DC46A0670DD125B95A981652236F99D9B681CBF87837EC99"
+ "6C6DA04453728610D0C6DDB58B318885D7D82C7F8DEB75CE7BD4FBAA"
+ "37089E6F9C6059F388838E7A00030B331EB76840910440B1B27AAEAE"
+ "EB4012B7D7665238A8E3FB004B117B58");
BigInteger expect_u = fromHex("CE38B9593487DA98554ED47D70A7AE5F462EF019");
BigInteger expect_S = fromHex("B0DC82BABCF30674AE450C0287745E7990A3381F63B387AAF271A10D"
+ "233861E359B48220F7C4693C9AE12B0A6F67809F0876E2D013800D6C"
+ "41BB59B6D5979B5C00A172B4A2A5903A0BDCAF8A709585EB2AFAFA8F"
+ "3499B200210DCC1F10EB33943CD67FC88A2F39A4BE5BEC4EC0A3212D"
+ "C346D7E474B29EDE8A469FFECA686E5A");
BigInteger k = SRP6Util.calculateK(new SHA1Digest(), N, g);
if (!k.equals(expect_k))
{
fail("wrong value of 'k'");
}
BigInteger x = SRP6Util.calculateX(new SHA1Digest(), N, s, I, P);
if (!x.equals(expect_x))
{
fail("wrong value of 'x'");
}
SRP6VerifierGenerator gen = new SRP6VerifierGenerator();
gen.init(N, g, new SHA1Digest());
BigInteger v = gen.generateVerifier(s, I, P);
if (!v.equals(expect_v))
{
fail("wrong value of 'v'");
}
final BigInteger aVal = a;
SRP6Client client = new SRP6Client()
{
protected BigInteger selectPrivateValue()
{
return aVal;
}
};
client.init(N, g, new SHA1Digest(), random);
BigInteger A = client.generateClientCredentials(s, I, P);
if (!A.equals(expect_A))
{
fail("wrong value of 'A'");
}
final BigInteger bVal = b;
SRP6Server server = new SRP6Server()
{
protected BigInteger selectPrivateValue()
{
return bVal;
}
};
server.init(N, g, v, new SHA1Digest(), random);
BigInteger B = server.generateServerCredentials();
if (!B.equals(expect_B))
{
fail("wrong value of 'B'");
}
BigInteger u = SRP6Util.calculateU(new SHA1Digest(), N, A, B);
if (!u.equals(expect_u))
{
fail("wrong value of 'u'");
}
BigInteger clientS = client.calculateSecret(B);
if (!clientS.equals(expect_S))
{
fail("wrong value of 'S' (client)");
}
BigInteger serverS = server.calculateSecret(A);
if (!serverS.equals(expect_S))
{
fail("wrong value of 'S' (server)");
}
}
private void testWithRandomParams(int bits) throws CryptoException
{
DHParametersGenerator paramGen = new DHParametersGenerator();
paramGen.init(bits, 25, random);
DHParameters parameters = paramGen.generateParameters();
testMutualVerification(new SRP6GroupParameters(parameters.getP(), parameters.getG()));
}
private void testMutualVerification(SRP6GroupParameters group) throws CryptoException
{
byte[] I = "username".getBytes();
byte[] P = "password".getBytes();
byte[] s = new byte[16];
random.nextBytes(s);
SRP6VerifierGenerator gen = new SRP6VerifierGenerator();
gen.init(group, new SHA256Digest());
BigInteger v = gen.generateVerifier(s, I, P);
SRP6Client client = new SRP6Client();
client.init(group, new SHA256Digest(), random);
SRP6Server server = new SRP6Server();
server.init(group, v, new SHA256Digest(), random);
BigInteger A = client.generateClientCredentials(s, I, P);
BigInteger B = server.generateServerCredentials();
BigInteger clientS = client.calculateSecret(B);
BigInteger serverS = server.calculateSecret(A);
if (!clientS.equals(serverS))
{
fail("SRP agreement failed - client/server calculated different secrets");
}
}
private void testClientCatchesBadB(SRP6GroupParameters group)
{
byte[] I = "username".getBytes();
byte[] P = "password".getBytes();
byte[] s = new byte[16];
random.nextBytes(s);
SRP6Client client = new SRP6Client();
client.init(group, new SHA256Digest(), random);
client.generateClientCredentials(s, I, P);
try
{
client.calculateSecret(ZERO);
fail("Client failed to detect invalid value for 'B'");
}
catch (CryptoException e)
{
// Expected
}
try
{
client.calculateSecret(group.getN());
fail("Client failed to detect invalid value for 'B'");
}
catch (CryptoException e)
{
// Expected
}
}
private void testServerCatchesBadA(SRP6GroupParameters group)
{
byte[] I = "username".getBytes();
byte[] P = "password".getBytes();
byte[] s = new byte[16];
random.nextBytes(s);
SRP6VerifierGenerator gen = new SRP6VerifierGenerator();
gen.init(group, new SHA256Digest());
BigInteger v = gen.generateVerifier(s, I, P);
SRP6Server server = new SRP6Server();
server.init(group, v, new SHA256Digest(), random);
server.generateServerCredentials();
try
{
server.calculateSecret(ZERO);
fail("Client failed to detect invalid value for 'A'");
}
catch (CryptoException e)
{
// Expected
}
try
{
server.calculateSecret(group.getN());
fail("Client failed to detect invalid value for 'A'");
}
catch (CryptoException e)
{
// Expected
}
}
public static void main(String[] args)
{
runTest(new SRP6Test());
}
}
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