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| <FONT color="green">001</FONT> /*<a name="line.1"></a> |
| <FONT color="green">002</FONT> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a> |
| <FONT color="green">003</FONT> * or more contributor license agreements. See the NOTICE file<a name="line.3"></a> |
| <FONT color="green">004</FONT> * distributed with this work for additional information<a name="line.4"></a> |
| <FONT color="green">005</FONT> * regarding copyright ownership. The ASF licenses this file<a name="line.5"></a> |
| <FONT color="green">006</FONT> * to you under the Apache License, Version 2.0 (the<a name="line.6"></a> |
| <FONT color="green">007</FONT> * "License"); you may not use this file except in compliance<a name="line.7"></a> |
| <FONT color="green">008</FONT> * with the License. You may obtain a copy of the License at<a name="line.8"></a> |
| <FONT color="green">009</FONT> *<a name="line.9"></a> |
| <FONT color="green">010</FONT> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a> |
| <FONT color="green">011</FONT> *<a name="line.11"></a> |
| <FONT color="green">012</FONT> * Unless required by applicable law or agreed to in writing,<a name="line.12"></a> |
| <FONT color="green">013</FONT> * software distributed under the License is distributed on an<a name="line.13"></a> |
| <FONT color="green">014</FONT> * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY<a name="line.14"></a> |
| <FONT color="green">015</FONT> * KIND, either express or implied. See the License for the<a name="line.15"></a> |
| <FONT color="green">016</FONT> * specific language governing permissions and limitations<a name="line.16"></a> |
| <FONT color="green">017</FONT> * under the License.<a name="line.17"></a> |
| <FONT color="green">018</FONT> */<a name="line.18"></a> |
| <FONT color="green">019</FONT> package org.apache.shiro.crypto;<a name="line.19"></a> |
| <FONT color="green">020</FONT> <a name="line.20"></a> |
| <FONT color="green">021</FONT> import org.apache.shiro.util.ByteSource;<a name="line.21"></a> |
| <FONT color="green">022</FONT> <a name="line.22"></a> |
| <FONT color="green">023</FONT> import java.io.InputStream;<a name="line.23"></a> |
| <FONT color="green">024</FONT> import java.io.OutputStream;<a name="line.24"></a> |
| <FONT color="green">025</FONT> <a name="line.25"></a> |
| <FONT color="green">026</FONT> /**<a name="line.26"></a> |
| <FONT color="green">027</FONT> * A {@code CipherService} uses a cryptographic algorithm called a<a name="line.27"></a> |
| <FONT color="green">028</FONT> * <a href="http://en.wikipedia.org/wiki/Cipher">Cipher</a> to convert an original input source using a {@code key} to<a name="line.28"></a> |
| <FONT color="green">029</FONT> * an uninterpretable format. The resulting encrypted output is only able to be converted back to original form with<a name="line.29"></a> |
| <FONT color="green">030</FONT> * a {@code key} as well. {@code CipherService}s can perform both encryption and decryption.<a name="line.30"></a> |
| <FONT color="green">031</FONT> * <h2>Cipher Basics</h2><a name="line.31"></a> |
| <FONT color="green">032</FONT> * For what is known as <em>Symmetric</em> {@code Cipher}s, the {@code Key} used to encrypt the source is the same<a name="line.32"></a> |
| <FONT color="green">033</FONT> * as (or trivially similar to) the {@code Key} used to decrypt it.<a name="line.33"></a> |
| <FONT color="green">034</FONT> * <p/><a name="line.34"></a> |
| <FONT color="green">035</FONT> * For <em>Asymmetric</em> {@code Cipher}s, the encryption {@code Key} is not the same as the decryption {@code Key}.<a name="line.35"></a> |
| <FONT color="green">036</FONT> * The most common type of Asymmetric Ciphers are based on what is called public/private key pairs:<a name="line.36"></a> |
| <FONT color="green">037</FONT> * <p/><a name="line.37"></a> |
| <FONT color="green">038</FONT> * A <em>private</em> key is known only to a single party, and as its name implies, is supposed be kept very private<a name="line.38"></a> |
| <FONT color="green">039</FONT> * and secure. A <em>public</em> key that is associated with the private key can be disseminated freely to anyone.<a name="line.39"></a> |
| <FONT color="green">040</FONT> * Then data encrypted by the public key can only be decrypted by the private key and vice versa, but neither party<a name="line.40"></a> |
| <FONT color="green">041</FONT> * need share their private key with anyone else. By not sharing a private key, you can guarantee no 3rd party can<a name="line.41"></a> |
| <FONT color="green">042</FONT> * intercept the key and therefore use it to decrypt a message.<a name="line.42"></a> |
| <FONT color="green">043</FONT> * <p/><a name="line.43"></a> |
| <FONT color="green">044</FONT> * This asymmetric key technology was created as a<a name="line.44"></a> |
| <FONT color="green">045</FONT> * more secure alternative to symmetric ciphers that sometimes suffer from man-in-the-middle attacks since, for<a name="line.45"></a> |
| <FONT color="green">046</FONT> * data shared between two parties, the same Key must also be shared and may be compromised.<a name="line.46"></a> |
| <FONT color="green">047</FONT> * <p/><a name="line.47"></a> |
| <FONT color="green">048</FONT> * Note that a symmetric cipher is perfectly fine to use if you just want to encode data in a format no one else<a name="line.48"></a> |
| <FONT color="green">049</FONT> * can understand and you never give away the key. Shiro uses a symmetric cipher when creating certain<a name="line.49"></a> |
| <FONT color="green">050</FONT> * HTTP Cookies for example - because it is often undesirable to have user's identity stored in a plain-text cookie,<a name="line.50"></a> |
| <FONT color="green">051</FONT> * that identity can be converted via a symmetric cipher. Since the the same exact Shiro application will receive<a name="line.51"></a> |
| <FONT color="green">052</FONT> * the cookie, it can decrypt it via the same {@code Key} and there is no potential for discovery since that Key<a name="line.52"></a> |
| <FONT color="green">053</FONT> * is never shared with anyone.<a name="line.53"></a> |
| <FONT color="green">054</FONT> * <h2>{@code CipherService}s vs JDK {@link javax.crypto.Cipher Cipher}s</h2><a name="line.54"></a> |
| <FONT color="green">055</FONT> * Shiro {@code CipherService}s essentially do the same things as JDK {@link javax.crypto.Cipher Cipher}s, but in<a name="line.55"></a> |
| <FONT color="green">056</FONT> * simpler and easier-to-use ways for most application developers. When thinking about encrypting and decrypting data<a name="line.56"></a> |
| <FONT color="green">057</FONT> * in an application, most app developers want what a {@code CipherService} provides, rather than having to manage the<a name="line.57"></a> |
| <FONT color="green">058</FONT> * lower-level intricacies of the JDK's {@code Cipher} API. Here are a few reasons why most people prefer<a name="line.58"></a> |
| <FONT color="green">059</FONT> * {@code CipherService}s:<a name="line.59"></a> |
| <FONT color="green">060</FONT> * <ul><a name="line.60"></a> |
| <FONT color="green">061</FONT> * <li><b>Stateless Methods</b> - {@code CipherService} method calls do not retain state between method invocations.<a name="line.61"></a> |
| <FONT color="green">062</FONT> * JDK {@code Cipher} instances do retain state across invocations, requiring its end-users to manage the instance<a name="line.62"></a> |
| <FONT color="green">063</FONT> * and its state themselves.</li><a name="line.63"></a> |
| <FONT color="green">064</FONT> * <li><b>Thread Safety</b> - {@code CipherService} instances are thread-safe inherently because no state is<a name="line.64"></a> |
| <FONT color="green">065</FONT> * retained across method invocations. JDK {@code Cipher} instances retain state and cannot be used by multiple<a name="line.65"></a> |
| <FONT color="green">066</FONT> * threads concurrently.</li><a name="line.66"></a> |
| <FONT color="green">067</FONT> * <li><b>Single Operation</b> - {@code CipherService} method calls are single operation methods: encryption or<a name="line.67"></a> |
| <FONT color="green">068</FONT> * decryption in their entirety are done as a single method call. This is ideal for the large majority of developer<a name="line.68"></a> |
| <FONT color="green">069</FONT> * needs where you have something unencrypted and just want it decrypted (or vice versa) in a single method call. In<a name="line.69"></a> |
| <FONT color="green">070</FONT> * contrast, JDK {@code Cipher} instances can support encrypting/decrypting data in chunks over time (because it<a name="line.70"></a> |
| <FONT color="green">071</FONT> * retains state), but this often introduces API clutter and confusion for most application developers.</li><a name="line.71"></a> |
| <FONT color="green">072</FONT> * <li><b>Type Safe</b> - There are {@code CipherService} implementations for different Cipher algorithms<a name="line.72"></a> |
| <FONT color="green">073</FONT> * ({@code AesCipherService}, {@code BlowfishCipherService}, etc). There is only one JDK {@code Cipher} class to<a name="line.73"></a> |
| <FONT color="green">074</FONT> * represent all cipher algorithms/instances.<a name="line.74"></a> |
| <FONT color="green">075</FONT> * <li><b>Simple Construction</b> - Because {@code CipherService} instances are type-safe, instantiating and using<a name="line.75"></a> |
| <FONT color="green">076</FONT> * one is often as simple as calling the default constructor, for example, <code>new AesCipherService();</code>. The<a name="line.76"></a> |
| <FONT color="green">077</FONT> * JDK {@code Cipher} class however requires using a procedural factory method with String arguments to indicate how<a name="line.77"></a> |
| <FONT color="green">078</FONT> * the instance should be created. The String arguments themselves are somewhat cryptic and hard to<a name="line.78"></a> |
| <FONT color="green">079</FONT> * understand unless you're a security expert. Shiro hides these details from you, but allows you to configure them<a name="line.79"></a> |
| <FONT color="green">080</FONT> * if you want.</li><a name="line.80"></a> |
| <FONT color="green">081</FONT> * </ul><a name="line.81"></a> |
| <FONT color="green">082</FONT> *<a name="line.82"></a> |
| <FONT color="green">083</FONT> * @see BlowfishCipherService<a name="line.83"></a> |
| <FONT color="green">084</FONT> * @see AesCipherService<a name="line.84"></a> |
| <FONT color="green">085</FONT> * @since 1.0<a name="line.85"></a> |
| <FONT color="green">086</FONT> */<a name="line.86"></a> |
| <FONT color="green">087</FONT> public interface CipherService {<a name="line.87"></a> |
| <FONT color="green">088</FONT> <a name="line.88"></a> |
| <FONT color="green">089</FONT> /**<a name="line.89"></a> |
| <FONT color="green">090</FONT> * Decrypts encrypted data via the specified cipher key and returns the original (pre-encrypted) data.<a name="line.90"></a> |
| <FONT color="green">091</FONT> * Note that the key must be in a format understood by the CipherService implementation.<a name="line.91"></a> |
| <FONT color="green">092</FONT> *<a name="line.92"></a> |
| <FONT color="green">093</FONT> * @param encrypted the previously encrypted data to decrypt<a name="line.93"></a> |
| <FONT color="green">094</FONT> * @param decryptionKey the cipher key used during decryption.<a name="line.94"></a> |
| <FONT color="green">095</FONT> * @return a byte source representing the original form of the specified encrypted data.<a name="line.95"></a> |
| <FONT color="green">096</FONT> * @throws CryptoException if there is an error during decryption<a name="line.96"></a> |
| <FONT color="green">097</FONT> */<a name="line.97"></a> |
| <FONT color="green">098</FONT> ByteSource decrypt(byte[] encrypted, byte[] decryptionKey) throws CryptoException;<a name="line.98"></a> |
| <FONT color="green">099</FONT> <a name="line.99"></a> |
| <FONT color="green">100</FONT> /**<a name="line.100"></a> |
| <FONT color="green">101</FONT> * Receives encrypted data from the given {@code InputStream}, decrypts it, and sends the resulting decrypted data<a name="line.101"></a> |
| <FONT color="green">102</FONT> * to the given {@code OutputStream}.<a name="line.102"></a> |
| <FONT color="green">103</FONT> * <p/><a name="line.103"></a> |
| <FONT color="green">104</FONT> * <b>NOTE:</b> This method <em>does NOT</em> flush or close either stream prior to returning - the caller must<a name="line.104"></a> |
| <FONT color="green">105</FONT> * do so when they are finished with the streams. For example:<a name="line.105"></a> |
| <FONT color="green">106</FONT> * <pre><a name="line.106"></a> |
| <FONT color="green">107</FONT> * try {<a name="line.107"></a> |
| <FONT color="green">108</FONT> * InputStream in = ...<a name="line.108"></a> |
| <FONT color="green">109</FONT> * OutputStream out = ...<a name="line.109"></a> |
| <FONT color="green">110</FONT> * cipherService.decrypt(in, out, decryptionKey);<a name="line.110"></a> |
| <FONT color="green">111</FONT> * } finally {<a name="line.111"></a> |
| <FONT color="green">112</FONT> * if (in != null) {<a name="line.112"></a> |
| <FONT color="green">113</FONT> * try {<a name="line.113"></a> |
| <FONT color="green">114</FONT> * in.close();<a name="line.114"></a> |
| <FONT color="green">115</FONT> * } catch (IOException ioe1) { ... log, trigger event, etc }<a name="line.115"></a> |
| <FONT color="green">116</FONT> * }<a name="line.116"></a> |
| <FONT color="green">117</FONT> * if (out != null) {<a name="line.117"></a> |
| <FONT color="green">118</FONT> * try {<a name="line.118"></a> |
| <FONT color="green">119</FONT> * out.close();<a name="line.119"></a> |
| <FONT color="green">120</FONT> * } catch (IOException ioe2) { ... log, trigger event, etc }<a name="line.120"></a> |
| <FONT color="green">121</FONT> * }<a name="line.121"></a> |
| <FONT color="green">122</FONT> * }<a name="line.122"></a> |
| <FONT color="green">123</FONT> * </pre><a name="line.123"></a> |
| <FONT color="green">124</FONT> *<a name="line.124"></a> |
| <FONT color="green">125</FONT> * @param in the stream supplying the data to decrypt<a name="line.125"></a> |
| <FONT color="green">126</FONT> * @param out the stream to send the decrypted data<a name="line.126"></a> |
| <FONT color="green">127</FONT> * @param decryptionKey the cipher key to use for decryption<a name="line.127"></a> |
| <FONT color="green">128</FONT> * @throws CryptoException if there is any problem during decryption.<a name="line.128"></a> |
| <FONT color="green">129</FONT> */<a name="line.129"></a> |
| <FONT color="green">130</FONT> void decrypt(InputStream in, OutputStream out, byte[] decryptionKey) throws CryptoException;<a name="line.130"></a> |
| <FONT color="green">131</FONT> <a name="line.131"></a> |
| <FONT color="green">132</FONT> /**<a name="line.132"></a> |
| <FONT color="green">133</FONT> * Encrypts data via the specified cipher key. Note that the key must be in a format understood by<a name="line.133"></a> |
| <FONT color="green">134</FONT> * the {@code CipherService} implementation.<a name="line.134"></a> |
| <FONT color="green">135</FONT> *<a name="line.135"></a> |
| <FONT color="green">136</FONT> * @param raw the data to encrypt<a name="line.136"></a> |
| <FONT color="green">137</FONT> * @param encryptionKey the cipher key used during encryption.<a name="line.137"></a> |
| <FONT color="green">138</FONT> * @return a byte source with the encrypted representation of the specified raw data.<a name="line.138"></a> |
| <FONT color="green">139</FONT> * @throws CryptoException if there is an error during encryption<a name="line.139"></a> |
| <FONT color="green">140</FONT> */<a name="line.140"></a> |
| <FONT color="green">141</FONT> ByteSource encrypt(byte[] raw, byte[] encryptionKey) throws CryptoException;<a name="line.141"></a> |
| <FONT color="green">142</FONT> <a name="line.142"></a> |
| <FONT color="green">143</FONT> /**<a name="line.143"></a> |
| <FONT color="green">144</FONT> * Receives the data from the given {@code InputStream}, encrypts it, and sends the resulting encrypted data to the<a name="line.144"></a> |
| <FONT color="green">145</FONT> * given {@code OutputStream}.<a name="line.145"></a> |
| <FONT color="green">146</FONT> * <p/><a name="line.146"></a> |
| <FONT color="green">147</FONT> * <b>NOTE:</b> This method <em>does NOT</em> flush or close either stream prior to returning - the caller must<a name="line.147"></a> |
| <FONT color="green">148</FONT> * do so when they are finished with the streams. For example:<a name="line.148"></a> |
| <FONT color="green">149</FONT> * <pre><a name="line.149"></a> |
| <FONT color="green">150</FONT> * try {<a name="line.150"></a> |
| <FONT color="green">151</FONT> * InputStream in = ...<a name="line.151"></a> |
| <FONT color="green">152</FONT> * OutputStream out = ...<a name="line.152"></a> |
| <FONT color="green">153</FONT> * cipherService.encrypt(in, out, encryptionKey);<a name="line.153"></a> |
| <FONT color="green">154</FONT> * } finally {<a name="line.154"></a> |
| <FONT color="green">155</FONT> * if (in != null) {<a name="line.155"></a> |
| <FONT color="green">156</FONT> * try {<a name="line.156"></a> |
| <FONT color="green">157</FONT> * in.close();<a name="line.157"></a> |
| <FONT color="green">158</FONT> * } catch (IOException ioe1) { ... log, trigger event, etc }<a name="line.158"></a> |
| <FONT color="green">159</FONT> * }<a name="line.159"></a> |
| <FONT color="green">160</FONT> * if (out != null) {<a name="line.160"></a> |
| <FONT color="green">161</FONT> * try {<a name="line.161"></a> |
| <FONT color="green">162</FONT> * out.close();<a name="line.162"></a> |
| <FONT color="green">163</FONT> * } catch (IOException ioe2) { ... log, trigger event, etc }<a name="line.163"></a> |
| <FONT color="green">164</FONT> * }<a name="line.164"></a> |
| <FONT color="green">165</FONT> * }<a name="line.165"></a> |
| <FONT color="green">166</FONT> * </pre><a name="line.166"></a> |
| <FONT color="green">167</FONT> *<a name="line.167"></a> |
| <FONT color="green">168</FONT> * @param in the stream supplying the data to encrypt<a name="line.168"></a> |
| <FONT color="green">169</FONT> * @param out the stream to send the encrypted data<a name="line.169"></a> |
| <FONT color="green">170</FONT> * @param encryptionKey the cipher key to use for encryption<a name="line.170"></a> |
| <FONT color="green">171</FONT> * @throws CryptoException if there is any problem during encryption.<a name="line.171"></a> |
| <FONT color="green">172</FONT> */<a name="line.172"></a> |
| <FONT color="green">173</FONT> void encrypt(InputStream in, OutputStream out, byte[] encryptionKey) throws CryptoException;<a name="line.173"></a> |
| <FONT color="green">174</FONT> <a name="line.174"></a> |
| <FONT color="green">175</FONT> }<a name="line.175"></a> |
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