DownloadableFile.java

  1package eu.siacs.conversations.entities;
  2
  3import java.io.File;
  4import java.io.FileInputStream;
  5import java.io.FileNotFoundException;
  6import java.io.FileOutputStream;
  7import java.io.InputStream;
  8import java.io.OutputStream;
  9import java.security.InvalidAlgorithmParameterException;
 10import java.security.InvalidKeyException;
 11import java.security.Key;
 12import java.security.NoSuchAlgorithmException;
 13
 14import javax.crypto.Cipher;
 15import javax.crypto.CipherInputStream;
 16import javax.crypto.CipherOutputStream;
 17import javax.crypto.NoSuchPaddingException;
 18import javax.crypto.spec.IvParameterSpec;
 19import javax.crypto.spec.SecretKeySpec;
 20
 21import eu.siacs.conversations.Config;
 22import android.util.Log;
 23
 24public class DownloadableFile extends File {
 25
 26	private static final long serialVersionUID = 2247012619505115863L;
 27
 28	private long expectedSize = 0;
 29	private String sha1sum;
 30	private Key aeskey;
 31
 32	private byte[] iv = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
 33			0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0xf };
 34
 35	public DownloadableFile(String path) {
 36		super(path);
 37	}
 38
 39	public long getSize() {
 40		return super.length();
 41	}
 42
 43	public long getExpectedSize() {
 44		if (this.aeskey != null) {
 45			if (this.expectedSize == 0) {
 46				return 0;
 47			} else {
 48				return (this.expectedSize / 16 + 1) * 16;
 49			}
 50		} else {
 51			return this.expectedSize;
 52		}
 53	}
 54
 55	public void setExpectedSize(long size) {
 56		this.expectedSize = size;
 57	}
 58
 59	public String getSha1Sum() {
 60		return this.sha1sum;
 61	}
 62
 63	public void setSha1Sum(String sum) {
 64		this.sha1sum = sum;
 65	}
 66
 67	public void setKey(byte[] key) {
 68		if (key.length == 48) {
 69			byte[] secretKey = new byte[32];
 70			byte[] iv = new byte[16];
 71			System.arraycopy(key, 0, iv, 0, 16);
 72			System.arraycopy(key, 16, secretKey, 0, 32);
 73			this.aeskey = new SecretKeySpec(secretKey, "AES");
 74			this.iv = iv;
 75		} else if (key.length >= 32) {
 76			byte[] secretKey = new byte[32];
 77			System.arraycopy(key, 0, secretKey, 0, 32);
 78			this.aeskey = new SecretKeySpec(secretKey, "AES");
 79		} else if (key.length >= 16) {
 80			byte[] secretKey = new byte[16];
 81			System.arraycopy(key, 0, secretKey, 0, 16);
 82			this.aeskey = new SecretKeySpec(secretKey, "AES");
 83		}
 84	}
 85
 86	public Key getKey() {
 87		return this.aeskey;
 88	}
 89
 90	public InputStream createInputStream() {
 91		if (this.getKey() == null) {
 92			try {
 93				return new FileInputStream(this);
 94			} catch (FileNotFoundException e) {
 95				return null;
 96			}
 97		} else {
 98			try {
 99				IvParameterSpec ips = new IvParameterSpec(iv);
100				Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
101				cipher.init(Cipher.ENCRYPT_MODE, this.getKey(), ips);
102				Log.d(Config.LOGTAG, "opening encrypted input stream");
103				return new CipherInputStream(new FileInputStream(this), cipher);
104			} catch (NoSuchAlgorithmException e) {
105				Log.d(Config.LOGTAG, "no such algo: " + e.getMessage());
106				return null;
107			} catch (NoSuchPaddingException e) {
108				Log.d(Config.LOGTAG, "no such padding: " + e.getMessage());
109				return null;
110			} catch (InvalidKeyException e) {
111				Log.d(Config.LOGTAG, "invalid key: " + e.getMessage());
112				return null;
113			} catch (InvalidAlgorithmParameterException e) {
114				Log.d(Config.LOGTAG, "invavid iv:" + e.getMessage());
115				return null;
116			} catch (FileNotFoundException e) {
117				return null;
118			}
119		}
120	}
121
122	public OutputStream createOutputStream() {
123		if (this.getKey() == null) {
124			try {
125				return new FileOutputStream(this);
126			} catch (FileNotFoundException e) {
127				return null;
128			}
129		} else {
130			try {
131				IvParameterSpec ips = new IvParameterSpec(this.iv);
132				Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
133				cipher.init(Cipher.DECRYPT_MODE, this.getKey(), ips);
134				Log.d(Config.LOGTAG, "opening encrypted output stream");
135				return new CipherOutputStream(new FileOutputStream(this),
136						cipher);
137			} catch (NoSuchAlgorithmException e) {
138				Log.d(Config.LOGTAG, "no such algo: " + e.getMessage());
139				return null;
140			} catch (NoSuchPaddingException e) {
141				Log.d(Config.LOGTAG, "no such padding: " + e.getMessage());
142				return null;
143			} catch (InvalidKeyException e) {
144				Log.d(Config.LOGTAG, "invalid key: " + e.getMessage());
145				return null;
146			} catch (InvalidAlgorithmParameterException e) {
147				Log.d(Config.LOGTAG, "invavid iv:" + e.getMessage());
148				return null;
149			} catch (FileNotFoundException e) {
150				return null;
151			}
152		}
153	}
154}