1 /* 2 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package sun.security.x509; 27 28 import java.io.IOException; 29 import java.util.Locale; 30 31 import sun.security.util.*; 32 33 /** 34 * This class implements the DNSName as required by the GeneralNames 35 * ASN.1 object. 36 * <p> 37 * [RFC2459] When the subjectAltName extension contains a domain name service 38 * label, the domain name MUST be stored in the dNSName (an IA5String). 39 * The name MUST be in the "preferred name syntax," as specified by RFC 40 * 1034 [RFC 1034]. Note that while upper and lower case letters are 41 * allowed in domain names, no signifigance is attached to the case. In 42 * addition, while the string " " is a legal domain name, subjectAltName 43 * extensions with a dNSName " " are not permitted. Finally, the use of 44 * the DNS representation for Internet mail addresses (wpolk.nist.gov 45 * instead of wpolk (at) nist.gov) is not permitted; such identities are to 46 * be encoded as rfc822Name. 47 * <p> 48 * @author Amit Kapoor 49 * @author Hemma Prafullchandra 50 */ 51 public class DNSName implements GeneralNameInterface { 52 private String name; 53 54 private static final String alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 55 private static final String digitsAndHyphen = "0123456789-"; 56 private static final String alphaDigitsAndHyphen = alpha + digitsAndHyphen; 57 58 /** 59 * Create the DNSName object from the passed encoded Der value. 60 * 61 * @param derValue the encoded DER DNSName. 62 * @exception IOException on error. 63 */ 64 public DNSName(DerValue derValue) throws IOException { 65 name = derValue.getIA5String(); 66 } 67 68 /** 69 * Create the DNSName object with the specified name. 70 * 71 * @param name the DNSName. 72 * @throws IOException if the name is not a valid DNSName subjectAltName 73 */ 74 public DNSName(String name) throws IOException { 75 if (name == null || name.length() == 0) 76 throw new IOException("DNS name must not be null"); 77 if (name.indexOf(' ') != -1) 78 throw new IOException("DNS names or NameConstraints with blank components are not permitted"); 79 if (name.charAt(0) == '.' || name.charAt(name.length() -1) == '.') 80 throw new IOException("DNS names or NameConstraints may not begin or end with a ."); 81 //Name will consist of label components separated by "." 82 //startIndex is the index of the first character of a component 83 //endIndex is the index of the last character of a component plus 1 84 for (int endIndex,startIndex=0; startIndex < name.length(); startIndex = endIndex+1) { 85 endIndex = name.indexOf('.', startIndex); 86 if (endIndex < 0) { 87 endIndex = name.length(); 88 } 89 if ((endIndex-startIndex) < 1) 90 throw new IOException("DNSName SubjectAltNames with empty components are not permitted"); 91 92 //DNSName components must begin with a letter A-Z or a-z 93 if (alpha.indexOf(name.charAt(startIndex)) < 0) 94 throw new IOException("DNSName components must begin with a letter"); 95 //nonStartIndex: index for characters in the component beyond the first one 96 for (int nonStartIndex=startIndex+1; nonStartIndex < endIndex; nonStartIndex++) { 97 char x = name.charAt(nonStartIndex); 98 if ((alphaDigitsAndHyphen).indexOf(x) < 0) 99 throw new IOException("DNSName components must consist of letters, digits, and hyphens"); 100 } 101 } 102 this.name = name; 103 } 104 105 /** 106 * Return the type of the GeneralName. 107 */ 108 public int getType() { 109 return (GeneralNameInterface.NAME_DNS); 110 } 111 112 /** 113 * Return the actual name value of the GeneralName. 114 */ 115 public String getName() { 116 return name; 117 } 118 119 /** 120 * Encode the DNS name into the DerOutputStream. 121 * 122 * @param out the DER stream to encode the DNSName to. 123 * @exception IOException on encoding errors. 124 */ 125 public void encode(DerOutputStream out) throws IOException { 126 out.putIA5String(name); 127 } 128 129 /** 130 * Convert the name into user readable string. 131 */ 132 public String toString() { 133 return ("DNSName: " + name); 134 } 135 136 /** 137 * Compares this name with another, for equality. 138 * 139 * @return true iff the names are equivalent 140 * according to RFC2459. 141 */ 142 public boolean equals(Object obj) { 143 if (this == obj) 144 return true; 145 146 if (!(obj instanceof DNSName)) 147 return false; 148 149 DNSName other = (DNSName)obj; 150 151 // RFC2459 mandates that these names are 152 // not case-sensitive 153 return name.equalsIgnoreCase(other.name); 154 } 155 156 /** 157 * Returns the hash code value for this object. 158 * 159 * @return a hash code value for this object. 160 */ 161 public int hashCode() { 162 return name.toUpperCase(Locale.ENGLISH).hashCode(); 163 } 164 165 /** 166 * Return type of constraint inputName places on this name:<ul> 167 * <li>NAME_DIFF_TYPE = -1: input name is different type from name (i.e. does not constrain). 168 * <li>NAME_MATCH = 0: input name matches name. 169 * <li>NAME_NARROWS = 1: input name narrows name (is lower in the naming subtree) 170 * <li>NAME_WIDENS = 2: input name widens name (is higher in the naming subtree) 171 * <li>NAME_SAME_TYPE = 3: input name does not match or narrow name, but is same type. 172 * </ul>. These results are used in checking NameConstraints during 173 * certification path verification. 174 * <p> 175 * RFC2459: DNS name restrictions are expressed as foo.bar.com. Any subdomain 176 * satisfies the name constraint. For example, www.foo.bar.com would 177 * satisfy the constraint but bigfoo.bar.com would not. 178 * <p> 179 * draft-ietf-pkix-new-part1-00.txt: DNS name restrictions are expressed as foo.bar.com. 180 * Any DNS name that 181 * can be constructed by simply adding to the left hand side of the name 182 * satisfies the name constraint. For example, www.foo.bar.com would 183 * satisfy the constraint but foo1.bar.com would not. 184 * <p> 185 * RFC1034: By convention, domain names can be stored with arbitrary case, but 186 * domain name comparisons for all present domain functions are done in a 187 * case-insensitive manner, assuming an ASCII character set, and a high 188 * order zero bit. 189 * <p> 190 * @param inputName to be checked for being constrained 191 * @returns constraint type above 192 * @throws UnsupportedOperationException if name is not exact match, but narrowing and widening are 193 * not supported for this name type. 194 */ 195 public int constrains(GeneralNameInterface inputName) throws UnsupportedOperationException { 196 int constraintType; 197 if (inputName == null) 198 constraintType = NAME_DIFF_TYPE; 199 else if (inputName.getType() != NAME_DNS) 200 constraintType = NAME_DIFF_TYPE; 201 else { 202 String inName = 203 (((DNSName)inputName).getName()).toLowerCase(Locale.ENGLISH); 204 String thisName = name.toLowerCase(Locale.ENGLISH); 205 if (inName.equals(thisName)) 206 constraintType = NAME_MATCH; 207 else if (thisName.endsWith(inName)) { 208 int inNdx = thisName.lastIndexOf(inName); 209 if (thisName.charAt(inNdx-1) == '.' ) 210 constraintType = NAME_WIDENS; 211 else 212 constraintType = NAME_SAME_TYPE; 213 } else if (inName.endsWith(thisName)) { 214 int ndx = inName.lastIndexOf(thisName); 215 if (inName.charAt(ndx-1) == '.' ) 216 constraintType = NAME_NARROWS; 217 else 218 constraintType = NAME_SAME_TYPE; 219 } else { 220 constraintType = NAME_SAME_TYPE; 221 } 222 } 223 return constraintType; 224 } 225 226 /** 227 * Return subtree depth of this name for purposes of determining 228 * NameConstraints minimum and maximum bounds and for calculating 229 * path lengths in name subtrees. 230 * 231 * @returns distance of name from root 232 * @throws UnsupportedOperationException if not supported for this name type 233 */ 234 public int subtreeDepth() throws UnsupportedOperationException { 235 // subtree depth is always at least 1 236 int sum = 1; 237 238 // count dots 239 for (int i = name.indexOf('.'); i >= 0; i = name.indexOf('.', i + 1)) { 240 ++sum; 241 } 242 243 return sum; 244 } 245 246 } 247