http://www.bouncycastle.org/java.html: The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.5. 
public class org.bouncycastle.crypto.signers.ECGOST3410Signer implements org.bouncycastle.crypto.DSA
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: org.bouncycastle.crypto.signers.ECGOST3410Signer
  super_class: java.lang.Object
{
  org.bouncycastle.crypto.params.ECKeyParameters key;
    descriptor: Lorg/bouncycastle/crypto/params/ECKeyParameters;
    flags: (0x0000) 

  java.security.SecureRandom random;
    descriptor: Ljava/security/SecureRandom;
    flags: (0x0000) 

  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // org.bouncycastle.crypto.signers.ECGOST3410Signer this
         0: .line 19
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // org.bouncycastle.crypto.signers.ECGOST3410Signer this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/bouncycastle/crypto/signers/ECGOST3410Signer;

  public void init(boolean, org.bouncycastle.crypto.CipherParameters);
    descriptor: (ZLorg/bouncycastle/crypto/CipherParameters;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=4, args_size=3
        start local 0 // org.bouncycastle.crypto.signers.ECGOST3410Signer this
        start local 1 // boolean forSigning
        start local 2 // org.bouncycastle.crypto.CipherParameters param
         0: .line 30
            iload 1 /* forSigning */
            ifeq 9
         1: .line 32
            aload 2 /* param */
            instanceof org.bouncycastle.crypto.params.ParametersWithRandom
            ifeq 6
         2: .line 34
            aload 2 /* param */
            checkcast org.bouncycastle.crypto.params.ParametersWithRandom
            astore 3 /* rParam */
        start local 3 // org.bouncycastle.crypto.params.ParametersWithRandom rParam
         3: .line 36
            aload 0 /* this */
            aload 3 /* rParam */
            invokevirtual org.bouncycastle.crypto.params.ParametersWithRandom.getRandom:()Ljava/security/SecureRandom;
            putfield org.bouncycastle.crypto.signers.ECGOST3410Signer.random:Ljava/security/SecureRandom;
         4: .line 37
            aload 0 /* this */
            aload 3 /* rParam */
            invokevirtual org.bouncycastle.crypto.params.ParametersWithRandom.getParameters:()Lorg/bouncycastle/crypto/CipherParameters;
            checkcast org.bouncycastle.crypto.params.ECPrivateKeyParameters
            putfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
        end local 3 // org.bouncycastle.crypto.params.ParametersWithRandom rParam
         5: .line 38
            goto 10
         6: .line 41
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            new java.security.SecureRandom
            dup
            invokespecial java.security.SecureRandom.<init>:()V
            putfield org.bouncycastle.crypto.signers.ECGOST3410Signer.random:Ljava/security/SecureRandom;
         7: .line 42
            aload 0 /* this */
            aload 2 /* param */
            checkcast org.bouncycastle.crypto.params.ECPrivateKeyParameters
            putfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
         8: .line 44
            goto 10
         9: .line 47
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            aload 2 /* param */
            checkcast org.bouncycastle.crypto.params.ECPublicKeyParameters
            putfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
        10: .line 49
      StackMap locals:
      StackMap stack:
            return
        end local 2 // org.bouncycastle.crypto.CipherParameters param
        end local 1 // boolean forSigning
        end local 0 // org.bouncycastle.crypto.signers.ECGOST3410Signer this
      LocalVariableTable:
        Start  End  Slot        Name  Signature
            0   11     0        this  Lorg/bouncycastle/crypto/signers/ECGOST3410Signer;
            0   11     1  forSigning  Z
            0   11     2       param  Lorg/bouncycastle/crypto/CipherParameters;
            3    5     3      rParam  Lorg/bouncycastle/crypto/params/ParametersWithRandom;
    MethodParameters:
            Name  Flags
      forSigning  
      param       

  public java.math.BigInteger[] generateSignature(byte[]);
    descriptor: ([B)[Ljava/math/BigInteger;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=10, args_size=2
        start local 0 // org.bouncycastle.crypto.signers.ECGOST3410Signer this
        start local 1 // byte[] message
         0: .line 61
            aload 1 /* message */
            arraylength
            newarray 8
            astore 2 /* mRev */
        start local 2 // byte[] mRev
         1: .line 62
            iconst_0
            istore 3 /* i */
        start local 3 // int i
         2: goto 5
         3: .line 64
      StackMap locals: byte[] int
      StackMap stack:
            aload 2 /* mRev */
            iload 3 /* i */
            aload 1 /* message */
            aload 2 /* mRev */
            arraylength
            iconst_1
            isub
            iload 3 /* i */
            isub
            baload
            bastore
         4: .line 62
            iinc 3 /* i */ 1
      StackMap locals:
      StackMap stack:
         5: iload 3 /* i */
            aload 2 /* mRev */
            arraylength
            if_icmpne 3
        end local 3 // int i
         6: .line 67
            new java.math.BigInteger
            dup
            iconst_1
            aload 2 /* mRev */
            invokespecial java.math.BigInteger.<init>:(I[B)V
            astore 3 /* e */
        start local 3 // java.math.BigInteger e
         7: .line 68
            aload 0 /* this */
            getfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
            invokevirtual org.bouncycastle.crypto.params.ECKeyParameters.getParameters:()Lorg/bouncycastle/crypto/params/ECDomainParameters;
            invokevirtual org.bouncycastle.crypto.params.ECDomainParameters.getN:()Ljava/math/BigInteger;
            astore 4 /* n */
        start local 4 // java.math.BigInteger n
         8: .line 70
            aconst_null
            astore 5 /* r */
        start local 5 // java.math.BigInteger r
         9: .line 71
            aconst_null
            astore 6 /* s */
        start local 6 // java.math.BigInteger s
        10: .line 75
      StackMap locals: org.bouncycastle.crypto.signers.ECGOST3410Signer byte[] byte[] java.math.BigInteger java.math.BigInteger java.math.BigInteger java.math.BigInteger
      StackMap stack:
            aconst_null
            astore 7 /* k */
        start local 7 // java.math.BigInteger k
        11: .line 81
      StackMap locals: java.math.BigInteger
      StackMap stack:
            new java.math.BigInteger
            dup
            aload 4 /* n */
            invokevirtual java.math.BigInteger.bitLength:()I
            aload 0 /* this */
            getfield org.bouncycastle.crypto.signers.ECGOST3410Signer.random:Ljava/security/SecureRandom;
            invokespecial java.math.BigInteger.<init>:(ILjava/util/Random;)V
            astore 7 /* k */
        12: .line 83
            aload 7 /* k */
            getstatic org.bouncycastle.math.ec.ECConstants.ZERO:Ljava/math/BigInteger;
            invokevirtual java.math.BigInteger.equals:(Ljava/lang/Object;)Z
            ifne 11
        13: .line 85
            aload 0 /* this */
            getfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
            invokevirtual org.bouncycastle.crypto.params.ECKeyParameters.getParameters:()Lorg/bouncycastle/crypto/params/ECDomainParameters;
            invokevirtual org.bouncycastle.crypto.params.ECDomainParameters.getG:()Lorg/bouncycastle/math/ec/ECPoint;
            aload 7 /* k */
            invokevirtual org.bouncycastle.math.ec.ECPoint.multiply:(Ljava/math/BigInteger;)Lorg/bouncycastle/math/ec/ECPoint;
            astore 8 /* p */
        start local 8 // org.bouncycastle.math.ec.ECPoint p
        14: .line 87
            aload 8 /* p */
            invokevirtual org.bouncycastle.math.ec.ECPoint.getX:()Lorg/bouncycastle/math/ec/ECFieldElement;
            invokevirtual org.bouncycastle.math.ec.ECFieldElement.toBigInteger:()Ljava/math/BigInteger;
            astore 9 /* x */
        start local 9 // java.math.BigInteger x
        15: .line 89
            aload 9 /* x */
            aload 4 /* n */
            invokevirtual java.math.BigInteger.mod:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            astore 5 /* r */
        end local 9 // java.math.BigInteger x
        end local 8 // org.bouncycastle.math.ec.ECPoint p
        16: .line 91
            aload 5 /* r */
            getstatic org.bouncycastle.math.ec.ECConstants.ZERO:Ljava/math/BigInteger;
            invokevirtual java.math.BigInteger.equals:(Ljava/lang/Object;)Z
            ifne 11
        17: .line 93
            aload 0 /* this */
            getfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
            checkcast org.bouncycastle.crypto.params.ECPrivateKeyParameters
            invokevirtual org.bouncycastle.crypto.params.ECPrivateKeyParameters.getD:()Ljava/math/BigInteger;
            astore 8 /* d */
        start local 8 // java.math.BigInteger d
        18: .line 95
            aload 7 /* k */
            aload 3 /* e */
            invokevirtual java.math.BigInteger.multiply:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            aload 8 /* d */
            aload 5 /* r */
            invokevirtual java.math.BigInteger.multiply:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            invokevirtual java.math.BigInteger.add:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            aload 4 /* n */
            invokevirtual java.math.BigInteger.mod:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            astore 6 /* s */
        end local 8 // java.math.BigInteger d
        end local 7 // java.math.BigInteger k
        19: .line 97
            aload 6 /* s */
            getstatic org.bouncycastle.math.ec.ECConstants.ZERO:Ljava/math/BigInteger;
            invokevirtual java.math.BigInteger.equals:(Ljava/lang/Object;)Z
            ifne 10
        20: .line 99
            iconst_2
            anewarray java.math.BigInteger
            astore 7 /* res */
        start local 7 // java.math.BigInteger[] res
        21: .line 101
            aload 7 /* res */
            iconst_0
            aload 5 /* r */
            aastore
        22: .line 102
            aload 7 /* res */
            iconst_1
            aload 6 /* s */
            aastore
        23: .line 104
            aload 7 /* res */
            areturn
        end local 7 // java.math.BigInteger[] res
        end local 6 // java.math.BigInteger s
        end local 5 // java.math.BigInteger r
        end local 4 // java.math.BigInteger n
        end local 3 // java.math.BigInteger e
        end local 2 // byte[] mRev
        end local 1 // byte[] message
        end local 0 // org.bouncycastle.crypto.signers.ECGOST3410Signer this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0   24     0     this  Lorg/bouncycastle/crypto/signers/ECGOST3410Signer;
            0   24     1  message  [B
            1   24     2     mRev  [B
            2    6     3        i  I
            7   24     3        e  Ljava/math/BigInteger;
            8   24     4        n  Ljava/math/BigInteger;
            9   24     5        r  Ljava/math/BigInteger;
           10   24     6        s  Ljava/math/BigInteger;
           11   19     7        k  Ljava/math/BigInteger;
           14   16     8        p  Lorg/bouncycastle/math/ec/ECPoint;
           15   16     9        x  Ljava/math/BigInteger;
           18   19     8        d  Ljava/math/BigInteger;
           21   24     7      res  [Ljava/math/BigInteger;
    MethodParameters:
         Name  Flags
      message  

  public boolean verifySignature(byte[], java.math.BigInteger, java.math.BigInteger);
    descriptor: ([BLjava/math/BigInteger;Ljava/math/BigInteger;)Z
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=14, args_size=4
        start local 0 // org.bouncycastle.crypto.signers.ECGOST3410Signer this
        start local 1 // byte[] message
        start local 2 // java.math.BigInteger r
        start local 3 // java.math.BigInteger s
         0: .line 117
            aload 1 /* message */
            arraylength
            newarray 8
            astore 4 /* mRev */
        start local 4 // byte[] mRev
         1: .line 118
            iconst_0
            istore 5 /* i */
        start local 5 // int i
         2: goto 5
         3: .line 120
      StackMap locals: byte[] int
      StackMap stack:
            aload 4 /* mRev */
            iload 5 /* i */
            aload 1 /* message */
            aload 4 /* mRev */
            arraylength
            iconst_1
            isub
            iload 5 /* i */
            isub
            baload
            bastore
         4: .line 118
            iinc 5 /* i */ 1
      StackMap locals:
      StackMap stack:
         5: iload 5 /* i */
            aload 4 /* mRev */
            arraylength
            if_icmpne 3
        end local 5 // int i
         6: .line 123
            new java.math.BigInteger
            dup
            iconst_1
            aload 4 /* mRev */
            invokespecial java.math.BigInteger.<init>:(I[B)V
            astore 5 /* e */
        start local 5 // java.math.BigInteger e
         7: .line 124
            aload 0 /* this */
            getfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
            invokevirtual org.bouncycastle.crypto.params.ECKeyParameters.getParameters:()Lorg/bouncycastle/crypto/params/ECDomainParameters;
            invokevirtual org.bouncycastle.crypto.params.ECDomainParameters.getN:()Ljava/math/BigInteger;
            astore 6 /* n */
        start local 6 // java.math.BigInteger n
         8: .line 127
            aload 2 /* r */
            getstatic org.bouncycastle.math.ec.ECConstants.ONE:Ljava/math/BigInteger;
            invokevirtual java.math.BigInteger.compareTo:(Ljava/math/BigInteger;)I
            iflt 9
            aload 2 /* r */
            aload 6 /* n */
            invokevirtual java.math.BigInteger.compareTo:(Ljava/math/BigInteger;)I
            iflt 10
         9: .line 129
      StackMap locals: org.bouncycastle.crypto.signers.ECGOST3410Signer byte[] java.math.BigInteger java.math.BigInteger byte[] java.math.BigInteger java.math.BigInteger
      StackMap stack:
            iconst_0
            ireturn
        10: .line 133
      StackMap locals:
      StackMap stack:
            aload 3 /* s */
            getstatic org.bouncycastle.math.ec.ECConstants.ONE:Ljava/math/BigInteger;
            invokevirtual java.math.BigInteger.compareTo:(Ljava/math/BigInteger;)I
            iflt 11
            aload 3 /* s */
            aload 6 /* n */
            invokevirtual java.math.BigInteger.compareTo:(Ljava/math/BigInteger;)I
            iflt 12
        11: .line 135
      StackMap locals:
      StackMap stack:
            iconst_0
            ireturn
        12: .line 138
      StackMap locals:
      StackMap stack:
            aload 5 /* e */
            aload 6 /* n */
            invokevirtual java.math.BigInteger.modInverse:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            astore 7 /* v */
        start local 7 // java.math.BigInteger v
        13: .line 140
            aload 3 /* s */
            aload 7 /* v */
            invokevirtual java.math.BigInteger.multiply:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            aload 6 /* n */
            invokevirtual java.math.BigInteger.mod:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            astore 8 /* z1 */
        start local 8 // java.math.BigInteger z1
        14: .line 141
            aload 6 /* n */
            aload 2 /* r */
            invokevirtual java.math.BigInteger.subtract:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            aload 7 /* v */
            invokevirtual java.math.BigInteger.multiply:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            aload 6 /* n */
            invokevirtual java.math.BigInteger.mod:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            astore 9 /* z2 */
        start local 9 // java.math.BigInteger z2
        15: .line 143
            aload 0 /* this */
            getfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
            invokevirtual org.bouncycastle.crypto.params.ECKeyParameters.getParameters:()Lorg/bouncycastle/crypto/params/ECDomainParameters;
            invokevirtual org.bouncycastle.crypto.params.ECDomainParameters.getG:()Lorg/bouncycastle/math/ec/ECPoint;
            astore 10 /* G */
        start local 10 // org.bouncycastle.math.ec.ECPoint G
        16: .line 144
            aload 0 /* this */
            getfield org.bouncycastle.crypto.signers.ECGOST3410Signer.key:Lorg/bouncycastle/crypto/params/ECKeyParameters;
            checkcast org.bouncycastle.crypto.params.ECPublicKeyParameters
            invokevirtual org.bouncycastle.crypto.params.ECPublicKeyParameters.getQ:()Lorg/bouncycastle/math/ec/ECPoint;
            astore 11 /* Q */
        start local 11 // org.bouncycastle.math.ec.ECPoint Q
        17: .line 146
            aload 10 /* G */
            aload 8 /* z1 */
            aload 11 /* Q */
            aload 9 /* z2 */
            invokestatic org.bouncycastle.math.ec.ECAlgorithms.sumOfTwoMultiplies:(Lorg/bouncycastle/math/ec/ECPoint;Ljava/math/BigInteger;Lorg/bouncycastle/math/ec/ECPoint;Ljava/math/BigInteger;)Lorg/bouncycastle/math/ec/ECPoint;
            astore 12 /* point */
        start local 12 // org.bouncycastle.math.ec.ECPoint point
        18: .line 148
            aload 12 /* point */
            invokevirtual org.bouncycastle.math.ec.ECPoint.getX:()Lorg/bouncycastle/math/ec/ECFieldElement;
            invokevirtual org.bouncycastle.math.ec.ECFieldElement.toBigInteger:()Ljava/math/BigInteger;
            aload 6 /* n */
            invokevirtual java.math.BigInteger.mod:(Ljava/math/BigInteger;)Ljava/math/BigInteger;
            astore 13 /* R */
        start local 13 // java.math.BigInteger R
        19: .line 150
            aload 13 /* R */
            aload 2 /* r */
            invokevirtual java.math.BigInteger.equals:(Ljava/lang/Object;)Z
            ireturn
        end local 13 // java.math.BigInteger R
        end local 12 // org.bouncycastle.math.ec.ECPoint point
        end local 11 // org.bouncycastle.math.ec.ECPoint Q
        end local 10 // org.bouncycastle.math.ec.ECPoint G
        end local 9 // java.math.BigInteger z2
        end local 8 // java.math.BigInteger z1
        end local 7 // java.math.BigInteger v
        end local 6 // java.math.BigInteger n
        end local 5 // java.math.BigInteger e
        end local 4 // byte[] mRev
        end local 3 // java.math.BigInteger s
        end local 2 // java.math.BigInteger r
        end local 1 // byte[] message
        end local 0 // org.bouncycastle.crypto.signers.ECGOST3410Signer this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0   20     0     this  Lorg/bouncycastle/crypto/signers/ECGOST3410Signer;
            0   20     1  message  [B
            0   20     2        r  Ljava/math/BigInteger;
            0   20     3        s  Ljava/math/BigInteger;
            1   20     4     mRev  [B
            2    6     5        i  I
            7   20     5        e  Ljava/math/BigInteger;
            8   20     6        n  Ljava/math/BigInteger;
           13   20     7        v  Ljava/math/BigInteger;
           14   20     8       z1  Ljava/math/BigInteger;
           15   20     9       z2  Ljava/math/BigInteger;
           16   20    10        G  Lorg/bouncycastle/math/ec/ECPoint;
           17   20    11        Q  Lorg/bouncycastle/math/ec/ECPoint;
           18   20    12    point  Lorg/bouncycastle/math/ec/ECPoint;
           19   20    13        R  Ljava/math/BigInteger;
    MethodParameters:
         Name  Flags
      message  
      r        
      s        
}
SourceFile: "ECGOST3410Signer.java"