| 1 | /**************************************************************** |
| 2 | * Licensed to the Apache Software Foundation (ASF) under one * |
| 3 | * or more contributor license agreements. See the NOTICE file * |
| 4 | * distributed with this work for additional information * |
| 5 | * regarding copyright ownership. The ASF licenses this file * |
| 6 | * to you under the Apache License, Version 2.0 (the * |
| 7 | * "License"); you may not use this file except in compliance * |
| 8 | * with the License. You may obtain a copy of the License at * |
| 9 | * * |
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 * |
| 11 | * * |
| 12 | * Unless required by applicable law or agreed to in writing, * |
| 13 | * software distributed under the License is distributed on an * |
| 14 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * |
| 15 | * KIND, either express or implied. See the License for the * |
| 16 | * specific language governing permissions and limitations * |
| 17 | * under the License. * |
| 18 | ****************************************************************/ |
| 19 | |
| 20 | package org.apache.james.jdkim.impl; |
| 21 | |
| 22 | import java.io.OutputStream; |
| 23 | import java.security.MessageDigest; |
| 24 | import java.security.NoSuchAlgorithmException; |
| 25 | |
| 26 | import org.apache.james.jdkim.api.BodyHasher; |
| 27 | import org.apache.james.jdkim.api.SignatureRecord; |
| 28 | import org.apache.james.jdkim.canon.DebugOutputStream; |
| 29 | import org.apache.james.jdkim.canon.DigestOutputStream; |
| 30 | import org.apache.james.jdkim.canon.LimitedOutputStream; |
| 31 | import org.apache.james.jdkim.canon.RelaxedBodyCanonicalizer; |
| 32 | import org.apache.james.jdkim.canon.SimpleBodyCanonicalizer; |
| 33 | import org.apache.james.jdkim.exceptions.PermFailException; |
| 34 | |
| 35 | public class BodyHasherImpl implements BodyHasher { |
| 36 | |
| 37 | private static final boolean DEEP_DEBUG = false; |
| 38 | private SignatureRecord sign; |
| 39 | private DigestOutputStream digesterOS; |
| 40 | private OutputStream out; |
| 41 | |
| 42 | public BodyHasherImpl(SignatureRecord sign) throws PermFailException { |
| 43 | MessageDigest md; |
| 44 | try { |
| 45 | md = MessageDigest.getInstance(sign.getHashAlgo().toString()); |
| 46 | } catch (NoSuchAlgorithmException e) { |
| 47 | throw new PermFailException("Unsupported algorythm: " |
| 48 | + sign.getHashAlgo(), e); |
| 49 | } |
| 50 | |
| 51 | int limit = sign.getBodyHashLimit(); |
| 52 | |
| 53 | // TODO enhance this to use a lookup service. |
| 54 | boolean relaxedBody = SignatureRecord.RELAXED.equals(sign |
| 55 | .getBodyCanonicalisationMethod()); |
| 56 | |
| 57 | if (!relaxedBody |
| 58 | && !SignatureRecord.SIMPLE.equals(sign |
| 59 | .getBodyCanonicalisationMethod())) { |
| 60 | throw new PermFailException( |
| 61 | "Unsupported body canonicalization method: " |
| 62 | + sign.getBodyCanonicalisationMethod()); |
| 63 | } |
| 64 | |
| 65 | DigestOutputStream dout = new DigestOutputStream(md); |
| 66 | |
| 67 | OutputStream out = dout; |
| 68 | if (DEEP_DEBUG) |
| 69 | out = new DebugOutputStream(out); |
| 70 | out = prepareCanonicalizerOutputStream(limit, relaxedBody, out); |
| 71 | |
| 72 | setSignatureRecord(sign); |
| 73 | setDigestOutputStream(dout); |
| 74 | setOutputStream(out); |
| 75 | } |
| 76 | |
| 77 | static OutputStream prepareCanonicalizerOutputStream(int limit, |
| 78 | boolean relaxedBody, OutputStream dout) { |
| 79 | OutputStream out = dout; |
| 80 | if (limit != -1) |
| 81 | out = new LimitedOutputStream(out, limit); |
| 82 | if (relaxedBody) |
| 83 | out = new RelaxedBodyCanonicalizer(out); |
| 84 | else |
| 85 | out = new SimpleBodyCanonicalizer(out); |
| 86 | return out; |
| 87 | } |
| 88 | |
| 89 | /** |
| 90 | * @see org.apache.james.jdkim.api.BodyHasher#getOutputStream() |
| 91 | */ |
| 92 | public OutputStream getOutputStream() { |
| 93 | return out; |
| 94 | } |
| 95 | |
| 96 | /** |
| 97 | * @see org.apache.james.jdkim.api.BodyHasher#getSignatureRecord() |
| 98 | */ |
| 99 | public SignatureRecord getSignatureRecord() { |
| 100 | return sign; |
| 101 | } |
| 102 | |
| 103 | private DigestOutputStream getDigesterOutputStream() { |
| 104 | return digesterOS; |
| 105 | } |
| 106 | |
| 107 | /** |
| 108 | * @see org.apache.james.jdkim.api.BodyHasher#getDigest() |
| 109 | */ |
| 110 | public byte[] getDigest() { |
| 111 | return getDigesterOutputStream().getDigest(); |
| 112 | } |
| 113 | |
| 114 | public void setSignatureRecord(SignatureRecord sign) { |
| 115 | this.sign = sign; |
| 116 | } |
| 117 | |
| 118 | public void setDigestOutputStream(DigestOutputStream dout) { |
| 119 | this.digesterOS = dout; |
| 120 | } |
| 121 | |
| 122 | public void setOutputStream(OutputStream out) { |
| 123 | this.out = out; |
| 124 | } |
| 125 | |
| 126 | } |