Package org.bouncycastle.crypto.io

Class CipherInputStream

  • All Implemented Interfaces:
    java.io.Closeable, java.lang.AutoCloseable
    public class CipherInputStream
extends java.io.FilterInputStream
    A CipherInputStream is composed of an InputStream and a cipher so that read() methods return data that are read in from the underlying InputStream but have been additionally processed by the Cipher. The cipher must be fully initialized before being used by a CipherInputStream.

    For example, if the Cipher is initialized for decryption, the CipherInputStream will attempt to read in data and decrypt them, before returning the decrypted data.

    • Field Summary

      • Fields inherited from class java.io.FilterInputStream

        in

    • Constructor Summary

      Constructors 
      Constructor Description
      CipherInputStream​(java.io.InputStream is, BufferedBlockCipher cipher)
      Constructs a CipherInputStream from an InputStream and a BufferedBlockCipher.
      CipherInputStream​(java.io.InputStream is, BufferedBlockCipher cipher, int bufSize)
      Constructs a CipherInputStream from an InputStream, a BufferedBlockCipher, and a specified internal buffer size.
      CipherInputStream​(java.io.InputStream is, AEADBlockCipher cipher)
      Constructs a CipherInputStream from an InputStream and an AEADBlockCipher.
      CipherInputStream​(java.io.InputStream is, AEADBlockCipher cipher, int bufSize)
      Constructs a CipherInputStream from an InputStream, an AEADBlockCipher, and a specified internal buffer size.
      CipherInputStream​(java.io.InputStream is, StreamCipher cipher)
      Constructs a CipherInputStream from an InputStream and a StreamCipher.
      CipherInputStream​(java.io.InputStream is, StreamCipher cipher, int bufSize)
      Constructs a CipherInputStream from an InputStream, a StreamCipher, and a specified internal buffer size.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int available()  
      void close()
      Closes the underlying input stream and finalises the processing of the data by the cipher.
      void mark​(int readlimit)
      Mark the current position.
      boolean markSupported()
      Return true if mark(readlimit) is supported.
      int read()
      Reads data from the underlying stream and processes it with the cipher until the cipher outputs data, and returns the next available byte.
      int read​(byte[] b)
      Reads data from the underlying stream and processes it with the cipher until the cipher outputs data, and then returns up to b.length bytes in the provided array.
      int read​(byte[] b, int off, int len)
      Reads data from the underlying stream and processes it with the cipher until the cipher outputs data, and then returns up to len bytes in the provided array.
      void reset()
      Reset to the last marked position, if supported.
      long skip​(long n)  

      • Methods inherited from class java.io.InputStream

        nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • CipherInputStream

        public CipherInputStream​(java.io.InputStream is,
                         BufferedBlockCipher cipher)
        Constructs a CipherInputStream from an InputStream and a BufferedBlockCipher.

      • CipherInputStream

        public CipherInputStream​(java.io.InputStream is,
                         StreamCipher cipher)
        Constructs a CipherInputStream from an InputStream and a StreamCipher.

      • CipherInputStream

        public CipherInputStream​(java.io.InputStream is,
                         AEADBlockCipher cipher)
        Constructs a CipherInputStream from an InputStream and an AEADBlockCipher.

      • CipherInputStream

        public CipherInputStream​(java.io.InputStream is,
                         BufferedBlockCipher cipher,
                         int bufSize)
        Constructs a CipherInputStream from an InputStream, a BufferedBlockCipher, and a specified internal buffer size.

      • CipherInputStream

        public CipherInputStream​(java.io.InputStream is,
                         StreamCipher cipher,
                         int bufSize)
        Constructs a CipherInputStream from an InputStream, a StreamCipher, and a specified internal buffer size.

      • CipherInputStream

        public CipherInputStream​(java.io.InputStream is,
                         AEADBlockCipher cipher,
                         int bufSize)
        Constructs a CipherInputStream from an InputStream, an AEADBlockCipher, and a specified internal buffer size.

    • Method Detail

      • read

        public int read()
         throws java.io.IOException
        Reads data from the underlying stream and processes it with the cipher until the cipher outputs data, and returns the next available byte.

        If the underlying stream is exhausted by this call, the cipher will be finalised.

        Overrides:
        read in class java.io.FilterInputStream
        Throws:
        java.io.IOException - if there was an error closing the input stream.
        InvalidCipherTextIOException - if the data read from the stream was invalid ciphertext (e.g. the cipher is an AEAD cipher and the ciphertext tag check fails).

      • read

        public int read​(byte[] b)
         throws java.io.IOException
        Reads data from the underlying stream and processes it with the cipher until the cipher outputs data, and then returns up to b.length bytes in the provided array.

        If the underlying stream is exhausted by this call, the cipher will be finalised.

        Overrides:
        read in class java.io.FilterInputStream
        Parameters:
        b - the buffer into which the data is read.
        Returns:
        the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
        Throws:
        java.io.IOException - if there was an error closing the input stream.
        InvalidCipherTextIOException - if the data read from the stream was invalid ciphertext (e.g. the cipher is an AEAD cipher and the ciphertext tag check fails).

      • read

        public int read​(byte[] b,
                int off,
                int len)
         throws java.io.IOException
        Reads data from the underlying stream and processes it with the cipher until the cipher outputs data, and then returns up to len bytes in the provided array.

        If the underlying stream is exhausted by this call, the cipher will be finalised.

        Overrides:
        read in class java.io.FilterInputStream
        Parameters:
        b - the buffer into which the data is read.
        off - the start offset in the destination array b
        len - the maximum number of bytes read.
        Returns:
        the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
        Throws:
        java.io.IOException - if there was an error closing the input stream.
        InvalidCipherTextIOException - if the data read from the stream was invalid ciphertext (e.g. the cipher is an AEAD cipher and the ciphertext tag check fails).

      • skip

        public long skip​(long n)
          throws java.io.IOException
        Overrides:
        skip in class java.io.FilterInputStream
        Throws:
        java.io.IOException

      • available

        public int available()
              throws java.io.IOException
        Overrides:
        available in class java.io.FilterInputStream
        Throws:
        java.io.IOException

      • close

        public void close()
           throws java.io.IOException
        Closes the underlying input stream and finalises the processing of the data by the cipher.
        Specified by:
        close in interface java.lang.AutoCloseable
        Specified by:
        close in interface java.io.Closeable
        Overrides:
        close in class java.io.FilterInputStream
        Throws:
        java.io.IOException - if there was an error closing the input stream.
        InvalidCipherTextIOException - if the data read from the stream was invalid ciphertext (e.g. the cipher is an AEAD cipher and the ciphertext tag check fails).

      • mark

        public void mark​(int readlimit)
        Mark the current position.

        This method only works if markSupported() returns true - which means the underlying stream supports marking, and the cipher passed in to this stream's constructor is a SkippingCipher (so capable of being reset to an arbitrary point easily).

        Overrides:
        mark in class java.io.FilterInputStream
        Parameters:
        readlimit - the maximum read ahead required before a reset() may be called.

      • reset

        public void reset()
           throws java.io.IOException
        Reset to the last marked position, if supported.
        Overrides:
        reset in class java.io.FilterInputStream
        Throws:
        java.io.IOException - if marking not supported by the cipher used, or the underlying stream.

      • markSupported

        public boolean markSupported()
        Return true if mark(readlimit) is supported. This will be true if the underlying stream supports marking and the cipher used is a SkippingCipher,
        Overrides:
        markSupported in class java.io.FilterInputStream
        Returns:
        true if mark(readlimit) supported, false otherwise.