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| <pre><span class="source-line-no">001</span><span id="line-1">/*</span> |
| <span class="source-line-no">002</span><span id="line-2"> * Licensed to the Apache Software Foundation (ASF) under one</span> |
| <span class="source-line-no">003</span><span id="line-3"> * or more contributor license agreements. See the NOTICE file</span> |
| <span class="source-line-no">004</span><span id="line-4"> * distributed with this work for additional information</span> |
| <span class="source-line-no">005</span><span id="line-5"> * regarding copyright ownership. The ASF licenses this file</span> |
| <span class="source-line-no">006</span><span id="line-6"> * to you under the Apache License, Version 2.0 (the</span> |
| <span class="source-line-no">007</span><span id="line-7"> * "License"); you may not use this file except in compliance</span> |
| <span class="source-line-no">008</span><span id="line-8"> * with the License. You may obtain a copy of the License at</span> |
| <span class="source-line-no">009</span><span id="line-9"> *</span> |
| <span class="source-line-no">010</span><span id="line-10"> * http://www.apache.org/licenses/LICENSE-2.0</span> |
| <span class="source-line-no">011</span><span id="line-11"> *</span> |
| <span class="source-line-no">012</span><span id="line-12"> * Unless required by applicable law or agreed to in writing, software</span> |
| <span class="source-line-no">013</span><span id="line-13"> * distributed under the License is distributed on an "AS IS" BASIS,</span> |
| <span class="source-line-no">014</span><span id="line-14"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span> |
| <span class="source-line-no">015</span><span id="line-15"> * See the License for the specific language governing permissions and</span> |
| <span class="source-line-no">016</span><span id="line-16"> * limitations under the License.</span> |
| <span class="source-line-no">017</span><span id="line-17"> */</span> |
| <span class="source-line-no">018</span><span id="line-18">package org.apache.hadoop.hbase.io.hfile;</span> |
| <span class="source-line-no">019</span><span id="line-19"></span> |
| <span class="source-line-no">020</span><span id="line-20">import java.io.IOException;</span> |
| <span class="source-line-no">021</span><span id="line-21">import java.nio.ByteBuffer;</span> |
| <span class="source-line-no">022</span><span id="line-22">import org.apache.hadoop.fs.ChecksumException;</span> |
| <span class="source-line-no">023</span><span id="line-23">import org.apache.hadoop.hbase.nio.ByteBuff;</span> |
| <span class="source-line-no">024</span><span id="line-24">import org.apache.hadoop.hbase.nio.SingleByteBuff;</span> |
| <span class="source-line-no">025</span><span id="line-25">import org.apache.hadoop.hbase.util.ChecksumType;</span> |
| <span class="source-line-no">026</span><span id="line-26">import org.apache.hadoop.util.DataChecksum;</span> |
| <span class="source-line-no">027</span><span id="line-27">import org.apache.yetus.audience.InterfaceAudience;</span> |
| <span class="source-line-no">028</span><span id="line-28">import org.slf4j.Logger;</span> |
| <span class="source-line-no">029</span><span id="line-29">import org.slf4j.LoggerFactory;</span> |
| <span class="source-line-no">030</span><span id="line-30"></span> |
| <span class="source-line-no">031</span><span id="line-31">/**</span> |
| <span class="source-line-no">032</span><span id="line-32"> * Utility methods to compute and validate checksums.</span> |
| <span class="source-line-no">033</span><span id="line-33"> */</span> |
| <span class="source-line-no">034</span><span id="line-34">@InterfaceAudience.Private</span> |
| <span class="source-line-no">035</span><span id="line-35">public class ChecksumUtil {</span> |
| <span class="source-line-no">036</span><span id="line-36"> public static final Logger LOG = LoggerFactory.getLogger(ChecksumUtil.class);</span> |
| <span class="source-line-no">037</span><span id="line-37"></span> |
| <span class="source-line-no">038</span><span id="line-38"> public static final int CHECKSUM_BUF_SIZE = 256;</span> |
| <span class="source-line-no">039</span><span id="line-39"></span> |
| <span class="source-line-no">040</span><span id="line-40"> /**</span> |
| <span class="source-line-no">041</span><span id="line-41"> * This is used by unit tests to make checksum failures throw an exception instead of returning</span> |
| <span class="source-line-no">042</span><span id="line-42"> * null. Returning a null value from checksum validation will cause the higher layer to retry that</span> |
| <span class="source-line-no">043</span><span id="line-43"> * read with hdfs-level checksums. Instead, we would like checksum failures to cause the entire</span> |
| <span class="source-line-no">044</span><span id="line-44"> * unit test to fail.</span> |
| <span class="source-line-no">045</span><span id="line-45"> */</span> |
| <span class="source-line-no">046</span><span id="line-46"> private static boolean generateExceptions = false;</span> |
| <span class="source-line-no">047</span><span id="line-47"></span> |
| <span class="source-line-no">048</span><span id="line-48"> /**</span> |
| <span class="source-line-no">049</span><span id="line-49"> * Generates a checksum for all the data in indata. The checksum is written to outdata.</span> |
| <span class="source-line-no">050</span><span id="line-50"> * @param indata input data stream</span> |
| <span class="source-line-no">051</span><span id="line-51"> * @param startOffset starting offset in the indata stream from where to compute checkums</span> |
| <span class="source-line-no">052</span><span id="line-52"> * from</span> |
| <span class="source-line-no">053</span><span id="line-53"> * @param endOffset ending offset in the indata stream upto which checksums needs to be</span> |
| <span class="source-line-no">054</span><span id="line-54"> * computed</span> |
| <span class="source-line-no">055</span><span id="line-55"> * @param outdata the output buffer where checksum values are written</span> |
| <span class="source-line-no">056</span><span id="line-56"> * @param outOffset the starting offset in the outdata where the checksum values are</span> |
| <span class="source-line-no">057</span><span id="line-57"> * written</span> |
| <span class="source-line-no">058</span><span id="line-58"> * @param checksumType type of checksum</span> |
| <span class="source-line-no">059</span><span id="line-59"> * @param bytesPerChecksum number of bytes per checksum value</span> |
| <span class="source-line-no">060</span><span id="line-60"> */</span> |
| <span class="source-line-no">061</span><span id="line-61"> static void generateChecksums(byte[] indata, int startOffset, int endOffset, byte[] outdata,</span> |
| <span class="source-line-no">062</span><span id="line-62"> int outOffset, ChecksumType checksumType, int bytesPerChecksum) throws IOException {</span> |
| <span class="source-line-no">063</span><span id="line-63"></span> |
| <span class="source-line-no">064</span><span id="line-64"> if (checksumType == ChecksumType.NULL) {</span> |
| <span class="source-line-no">065</span><span id="line-65"> return; // No checksum for this block.</span> |
| <span class="source-line-no">066</span><span id="line-66"> }</span> |
| <span class="source-line-no">067</span><span id="line-67"></span> |
| <span class="source-line-no">068</span><span id="line-68"> DataChecksum checksum =</span> |
| <span class="source-line-no">069</span><span id="line-69"> DataChecksum.newDataChecksum(checksumType.getDataChecksumType(), bytesPerChecksum);</span> |
| <span class="source-line-no">070</span><span id="line-70"></span> |
| <span class="source-line-no">071</span><span id="line-71"> checksum.calculateChunkedSums(ByteBuffer.wrap(indata, startOffset, endOffset - startOffset),</span> |
| <span class="source-line-no">072</span><span id="line-72"> ByteBuffer.wrap(outdata, outOffset, outdata.length - outOffset));</span> |
| <span class="source-line-no">073</span><span id="line-73"> }</span> |
| <span class="source-line-no">074</span><span id="line-74"></span> |
| <span class="source-line-no">075</span><span id="line-75"> /**</span> |
| <span class="source-line-no">076</span><span id="line-76"> * Like the hadoop's {@link DataChecksum#verifyChunkedSums(ByteBuffer, ByteBuffer, String, long)},</span> |
| <span class="source-line-no">077</span><span id="line-77"> * this method will also verify checksum of each chunk in data. the difference is: this method can</span> |
| <span class="source-line-no">078</span><span id="line-78"> * accept {@link ByteBuff} as arguments, we can not add it in hadoop-common so defined here.</span> |
| <span class="source-line-no">079</span><span id="line-79"> * @param dataChecksum to calculate the checksum.</span> |
| <span class="source-line-no">080</span><span id="line-80"> * @param data as the input</span> |
| <span class="source-line-no">081</span><span id="line-81"> * @param checksums to compare</span> |
| <span class="source-line-no">082</span><span id="line-82"> * @param pathName indicate that the data is read from which file.</span> |
| <span class="source-line-no">083</span><span id="line-83"> * @return a flag indicate the checksum match or mismatch.</span> |
| <span class="source-line-no">084</span><span id="line-84"> * @see org.apache.hadoop.util.DataChecksum#verifyChunkedSums(ByteBuffer, ByteBuffer, String,</span> |
| <span class="source-line-no">085</span><span id="line-85"> * long)</span> |
| <span class="source-line-no">086</span><span id="line-86"> */</span> |
| <span class="source-line-no">087</span><span id="line-87"> private static boolean verifyChunkedSums(DataChecksum dataChecksum, ByteBuff data,</span> |
| <span class="source-line-no">088</span><span id="line-88"> ByteBuff checksums, String pathName) {</span> |
| <span class="source-line-no">089</span><span id="line-89"> // Almost all of the HFile Block are about 64KB, and it would be a SingleByteBuff, use the</span> |
| <span class="source-line-no">090</span><span id="line-90"> // Hadoop's verify checksum directly, because it'll use the native checksum, which has no extra</span> |
| <span class="source-line-no">091</span><span id="line-91"> // byte[] allocation or copying. (HBASE-21917)</span> |
| <span class="source-line-no">092</span><span id="line-92"> if (data instanceof SingleByteBuff && checksums instanceof SingleByteBuff) {</span> |
| <span class="source-line-no">093</span><span id="line-93"> // the checksums ByteBuff must also be an SingleByteBuff because it's duplicated from data.</span> |
| <span class="source-line-no">094</span><span id="line-94"> ByteBuffer dataBB = (ByteBuffer) (data.nioByteBuffers()[0]).duplicate()</span> |
| <span class="source-line-no">095</span><span id="line-95"> .position(data.position()).limit(data.limit());</span> |
| <span class="source-line-no">096</span><span id="line-96"> ByteBuffer checksumBB = (ByteBuffer) (checksums.nioByteBuffers()[0]).duplicate()</span> |
| <span class="source-line-no">097</span><span id="line-97"> .position(checksums.position()).limit(checksums.limit());</span> |
| <span class="source-line-no">098</span><span id="line-98"> try {</span> |
| <span class="source-line-no">099</span><span id="line-99"> dataChecksum.verifyChunkedSums(dataBB, checksumBB, pathName, 0);</span> |
| <span class="source-line-no">100</span><span id="line-100"> return true;</span> |
| <span class="source-line-no">101</span><span id="line-101"> } catch (ChecksumException e) {</span> |
| <span class="source-line-no">102</span><span id="line-102"> return false;</span> |
| <span class="source-line-no">103</span><span id="line-103"> }</span> |
| <span class="source-line-no">104</span><span id="line-104"> }</span> |
| <span class="source-line-no">105</span><span id="line-105"></span> |
| <span class="source-line-no">106</span><span id="line-106"> // If the block is a MultiByteBuff. we use a small byte[] to update the checksum many times for</span> |
| <span class="source-line-no">107</span><span id="line-107"> // reducing GC pressure. it's a rare case.</span> |
| <span class="source-line-no">108</span><span id="line-108"> int checksumTypeSize = dataChecksum.getChecksumType().size;</span> |
| <span class="source-line-no">109</span><span id="line-109"> if (checksumTypeSize == 0) {</span> |
| <span class="source-line-no">110</span><span id="line-110"> return true;</span> |
| <span class="source-line-no">111</span><span id="line-111"> }</span> |
| <span class="source-line-no">112</span><span id="line-112"> // we have 5 checksum type now: NULL,DEFAULT,MIXED,CRC32,CRC32C. the former three need 0 byte,</span> |
| <span class="source-line-no">113</span><span id="line-113"> // and the other two need 4 bytes.</span> |
| <span class="source-line-no">114</span><span id="line-114"> assert checksumTypeSize == 4;</span> |
| <span class="source-line-no">115</span><span id="line-115"></span> |
| <span class="source-line-no">116</span><span id="line-116"> int bytesPerChecksum = dataChecksum.getBytesPerChecksum();</span> |
| <span class="source-line-no">117</span><span id="line-117"> int startDataPos = data.position();</span> |
| <span class="source-line-no">118</span><span id="line-118"> data.mark();</span> |
| <span class="source-line-no">119</span><span id="line-119"> checksums.mark();</span> |
| <span class="source-line-no">120</span><span id="line-120"> try {</span> |
| <span class="source-line-no">121</span><span id="line-121"> // allocate an small buffer for reducing young GC (HBASE-21917), and copy 256 bytes from</span> |
| <span class="source-line-no">122</span><span id="line-122"> // ByteBuff to update the checksum each time. if we upgrade to an future JDK and hadoop</span> |
| <span class="source-line-no">123</span><span id="line-123"> // version which support DataCheckSum#update(ByteBuffer), we won't need to update the checksum</span> |
| <span class="source-line-no">124</span><span id="line-124"> // multiple times then.</span> |
| <span class="source-line-no">125</span><span id="line-125"> byte[] buf = new byte[CHECKSUM_BUF_SIZE];</span> |
| <span class="source-line-no">126</span><span id="line-126"> byte[] sum = new byte[checksumTypeSize];</span> |
| <span class="source-line-no">127</span><span id="line-127"> while (data.remaining() > 0) {</span> |
| <span class="source-line-no">128</span><span id="line-128"> int n = Math.min(data.remaining(), bytesPerChecksum);</span> |
| <span class="source-line-no">129</span><span id="line-129"> checksums.get(sum);</span> |
| <span class="source-line-no">130</span><span id="line-130"> dataChecksum.reset();</span> |
| <span class="source-line-no">131</span><span id="line-131"> for (int remain = n, len; remain > 0; remain -= len) {</span> |
| <span class="source-line-no">132</span><span id="line-132"> // Copy 256 bytes from ByteBuff to update the checksum each time, if the remaining</span> |
| <span class="source-line-no">133</span><span id="line-133"> // bytes is less than 256, then just update the remaining bytes.</span> |
| <span class="source-line-no">134</span><span id="line-134"> len = Math.min(CHECKSUM_BUF_SIZE, remain);</span> |
| <span class="source-line-no">135</span><span id="line-135"> data.get(buf, 0, len);</span> |
| <span class="source-line-no">136</span><span id="line-136"> dataChecksum.update(buf, 0, len);</span> |
| <span class="source-line-no">137</span><span id="line-137"> }</span> |
| <span class="source-line-no">138</span><span id="line-138"> int calculated = (int) dataChecksum.getValue();</span> |
| <span class="source-line-no">139</span><span id="line-139"> int stored = (sum[0] << 24 & 0xff000000) | (sum[1] << 16 & 0xff0000)</span> |
| <span class="source-line-no">140</span><span id="line-140"> | (sum[2] << 8 & 0xff00) | (sum[3] & 0xff);</span> |
| <span class="source-line-no">141</span><span id="line-141"> if (calculated != stored) {</span> |
| <span class="source-line-no">142</span><span id="line-142"> if (LOG.isTraceEnabled()) {</span> |
| <span class="source-line-no">143</span><span id="line-143"> long errPos = data.position() - startDataPos - n;</span> |
| <span class="source-line-no">144</span><span id="line-144"> LOG.trace("Checksum error: {} at {} expected: {} got: {}", pathName, errPos, stored,</span> |
| <span class="source-line-no">145</span><span id="line-145"> calculated);</span> |
| <span class="source-line-no">146</span><span id="line-146"> }</span> |
| <span class="source-line-no">147</span><span id="line-147"> return false;</span> |
| <span class="source-line-no">148</span><span id="line-148"> }</span> |
| <span class="source-line-no">149</span><span id="line-149"> }</span> |
| <span class="source-line-no">150</span><span id="line-150"> } finally {</span> |
| <span class="source-line-no">151</span><span id="line-151"> data.reset();</span> |
| <span class="source-line-no">152</span><span id="line-152"> checksums.reset();</span> |
| <span class="source-line-no">153</span><span id="line-153"> }</span> |
| <span class="source-line-no">154</span><span id="line-154"> return true;</span> |
| <span class="source-line-no">155</span><span id="line-155"> }</span> |
| <span class="source-line-no">156</span><span id="line-156"></span> |
| <span class="source-line-no">157</span><span id="line-157"> /**</span> |
| <span class="source-line-no">158</span><span id="line-158"> * Validates that the data in the specified HFileBlock matches the checksum. Generates the</span> |
| <span class="source-line-no">159</span><span id="line-159"> * checksums for the data and then validate that it matches those stored in the end of the data.</span> |
| <span class="source-line-no">160</span><span id="line-160"> * @param buf Contains the data in following order: HFileBlock header, data, checksums.</span> |
| <span class="source-line-no">161</span><span id="line-161"> * @param pathName Path of the HFile to which the {@code data} belongs. Only used for logging.</span> |
| <span class="source-line-no">162</span><span id="line-162"> * @param offset offset of the data being validated. Only used for logging.</span> |
| <span class="source-line-no">163</span><span id="line-163"> * @param hdrSize Size of the block header in {@code data}. Only used for logging.</span> |
| <span class="source-line-no">164</span><span id="line-164"> * @return True if checksum matches, else false.</span> |
| <span class="source-line-no">165</span><span id="line-165"> */</span> |
| <span class="source-line-no">166</span><span id="line-166"> static boolean validateChecksum(ByteBuff buf, String pathName, long offset, int hdrSize) {</span> |
| <span class="source-line-no">167</span><span id="line-167"> ChecksumType ctype = ChecksumType.codeToType(buf.get(HFileBlock.Header.CHECKSUM_TYPE_INDEX));</span> |
| <span class="source-line-no">168</span><span id="line-168"> if (ctype == ChecksumType.NULL) {</span> |
| <span class="source-line-no">169</span><span id="line-169"> return true;// No checksum validations needed for this block.</span> |
| <span class="source-line-no">170</span><span id="line-170"> }</span> |
| <span class="source-line-no">171</span><span id="line-171"></span> |
| <span class="source-line-no">172</span><span id="line-172"> // read in the stored value of the checksum size from the header.</span> |
| <span class="source-line-no">173</span><span id="line-173"> int bytesPerChecksum = buf.getInt(HFileBlock.Header.BYTES_PER_CHECKSUM_INDEX);</span> |
| <span class="source-line-no">174</span><span id="line-174"> DataChecksum dataChecksum =</span> |
| <span class="source-line-no">175</span><span id="line-175"> DataChecksum.newDataChecksum(ctype.getDataChecksumType(), bytesPerChecksum);</span> |
| <span class="source-line-no">176</span><span id="line-176"> assert dataChecksum != null;</span> |
| <span class="source-line-no">177</span><span id="line-177"> int onDiskDataSizeWithHeader =</span> |
| <span class="source-line-no">178</span><span id="line-178"> buf.getInt(HFileBlock.Header.ON_DISK_DATA_SIZE_WITH_HEADER_INDEX);</span> |
| <span class="source-line-no">179</span><span id="line-179"> LOG.trace(</span> |
| <span class="source-line-no">180</span><span id="line-180"> "dataLength={}, sizeWithHeader={}, checksumType={}, file={}, "</span> |
| <span class="source-line-no">181</span><span id="line-181"> + "offset={}, headerSize={}, bytesPerChecksum={}",</span> |
| <span class="source-line-no">182</span><span id="line-182"> buf.capacity(), onDiskDataSizeWithHeader, ctype.getName(), pathName, offset, hdrSize,</span> |
| <span class="source-line-no">183</span><span id="line-183"> bytesPerChecksum);</span> |
| <span class="source-line-no">184</span><span id="line-184"> ByteBuff data = buf.duplicate().position(0).limit(onDiskDataSizeWithHeader);</span> |
| <span class="source-line-no">185</span><span id="line-185"> ByteBuff checksums = buf.duplicate().position(onDiskDataSizeWithHeader).limit(buf.limit());</span> |
| <span class="source-line-no">186</span><span id="line-186"> return verifyChunkedSums(dataChecksum, data, checksums, pathName);</span> |
| <span class="source-line-no">187</span><span id="line-187"> }</span> |
| <span class="source-line-no">188</span><span id="line-188"></span> |
| <span class="source-line-no">189</span><span id="line-189"> /**</span> |
| <span class="source-line-no">190</span><span id="line-190"> * Returns the number of bytes needed to store the checksums for a specified data size</span> |
| <span class="source-line-no">191</span><span id="line-191"> * @param datasize number of bytes of data</span> |
| <span class="source-line-no">192</span><span id="line-192"> * @param bytesPerChecksum number of bytes in a checksum chunk</span> |
| <span class="source-line-no">193</span><span id="line-193"> * @return The number of bytes needed to store the checksum values</span> |
| <span class="source-line-no">194</span><span id="line-194"> */</span> |
| <span class="source-line-no">195</span><span id="line-195"> static long numBytes(long datasize, int bytesPerChecksum) {</span> |
| <span class="source-line-no">196</span><span id="line-196"> return numChunks(datasize, bytesPerChecksum) * HFileBlock.CHECKSUM_SIZE;</span> |
| <span class="source-line-no">197</span><span id="line-197"> }</span> |
| <span class="source-line-no">198</span><span id="line-198"></span> |
| <span class="source-line-no">199</span><span id="line-199"> /**</span> |
| <span class="source-line-no">200</span><span id="line-200"> * Returns the number of checksum chunks needed to store the checksums for a specified data size</span> |
| <span class="source-line-no">201</span><span id="line-201"> * @param datasize number of bytes of data</span> |
| <span class="source-line-no">202</span><span id="line-202"> * @param bytesPerChecksum number of bytes in a checksum chunk</span> |
| <span class="source-line-no">203</span><span id="line-203"> * @return The number of checksum chunks</span> |
| <span class="source-line-no">204</span><span id="line-204"> */</span> |
| <span class="source-line-no">205</span><span id="line-205"> static long numChunks(long datasize, int bytesPerChecksum) {</span> |
| <span class="source-line-no">206</span><span id="line-206"> long numChunks = datasize / bytesPerChecksum;</span> |
| <span class="source-line-no">207</span><span id="line-207"> if (datasize % bytesPerChecksum != 0) {</span> |
| <span class="source-line-no">208</span><span id="line-208"> numChunks++;</span> |
| <span class="source-line-no">209</span><span id="line-209"> }</span> |
| <span class="source-line-no">210</span><span id="line-210"> return numChunks;</span> |
| <span class="source-line-no">211</span><span id="line-211"> }</span> |
| <span class="source-line-no">212</span><span id="line-212"></span> |
| <span class="source-line-no">213</span><span id="line-213"> /**</span> |
| <span class="source-line-no">214</span><span id="line-214"> * Mechanism to throw an exception in case of hbase checksum failure. This is used by unit tests</span> |
| <span class="source-line-no">215</span><span id="line-215"> * only.</span> |
| <span class="source-line-no">216</span><span id="line-216"> * @param value Setting this to true will cause hbase checksum verification failures to generate</span> |
| <span class="source-line-no">217</span><span id="line-217"> * exceptions.</span> |
| <span class="source-line-no">218</span><span id="line-218"> */</span> |
| <span class="source-line-no">219</span><span id="line-219"> public static void generateExceptionForChecksumFailureForTest(boolean value) {</span> |
| <span class="source-line-no">220</span><span id="line-220"> generateExceptions = value;</span> |
| <span class="source-line-no">221</span><span id="line-221"> }</span> |
| <span class="source-line-no">222</span><span id="line-222">}</span> |
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| </pre> |
| </div> |
| </main> |
| </body> |
| </html> |
