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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package sun.security.x509;
import java.io.IOException;
import java.util.Locale;
import sun.security.util.*;
/**
* This class implements the DNSName as required by the GeneralNames
* ASN.1 object.
* <p>
* [RFC2459] When the subjectAltName extension contains a domain name service
* label, the domain name MUST be stored in the dNSName (an IA5String).
* The name MUST be in the "preferred name syntax," as specified by RFC
* 1034 [RFC 1034]. Note that while upper and lower case letters are
* allowed in domain names, no signifigance is attached to the case. In
* addition, while the string " " is a legal domain name, subjectAltName
* extensions with a dNSName " " are not permitted. Finally, the use of
* the DNS representation for Internet mail addresses (wpolk.nist.gov
* instead of wpolk@nist.gov) is not permitted; such identities are to
* be encoded as rfc822Name.
* <p>
* @author Amit Kapoor
* @author Hemma Prafullchandra
*/
public class DNSName implements GeneralNameInterface {
private String name;
private static final String alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
private static final String digitsAndHyphen = "0123456789-";
private static final String alphaDigitsAndHyphen = alpha + digitsAndHyphen;
/**
* Create the DNSName object from the passed encoded Der value.
*
* @param derValue the encoded DER DNSName.
* @exception IOException on error.
*/
public DNSName(DerValue derValue) throws IOException {
name = derValue.getIA5String();
}
/**
* Create the DNSName object with the specified name.
*
* @param name the DNSName.
* @throws IOException if the name is not a valid DNSName subjectAltName
*/
public DNSName(String name) throws IOException {
if (name == null || name.length() == 0)
throw new IOException("DNS name must not be null");
if (name.indexOf(' ') != -1)
throw new IOException("DNS names or NameConstraints with blank components are not permitted");
if (name.charAt(0) == '.' || name.charAt(name.length() -1) == '.')
throw new IOException("DNS names or NameConstraints may not begin or end with a .");
//Name will consist of label components separated by "."
//startIndex is the index of the first character of a component
//endIndex is the index of the last character of a component plus 1
for (int endIndex,startIndex=0; startIndex < name.length(); startIndex = endIndex+1) {
endIndex = name.indexOf('.', startIndex);
if (endIndex < 0) {
endIndex = name.length();
}
if ((endIndex-startIndex) < 1)
throw new IOException("DNSName SubjectAltNames with empty components are not permitted");
//DNSName components must begin with a letter A-Z or a-z
if (alpha.indexOf(name.charAt(startIndex)) < 0)
throw new IOException("DNSName components must begin with a letter");
//nonStartIndex: index for characters in the component beyond the first one
for (int nonStartIndex=startIndex+1; nonStartIndex < endIndex; nonStartIndex++) {
char x = name.charAt(nonStartIndex);
if ((alphaDigitsAndHyphen).indexOf(x) < 0)
throw new IOException("DNSName components must consist of letters, digits, and hyphens");
}
}
this.name = name;
}
/**
* Return the type of the GeneralName.
*/
public int getType() {
return (GeneralNameInterface.NAME_DNS);
}
/**
* Return the actual name value of the GeneralName.
*/
public String getName() {
return name;
}
/**
* Encode the DNS name into the DerOutputStream.
*
* @param out the DER stream to encode the DNSName to.
* @exception IOException on encoding errors.
*/
public void encode(DerOutputStream out) throws IOException {
out.putIA5String(name);
}
/**
* Convert the name into user readable string.
*/
public String toString() {
return ("DNSName: " + name);
}
/**
* Compares this name with another, for equality.
*
* @return true iff the names are equivalent
* according to RFC2459.
*/
public boolean equals(Object obj) {
if (this == obj)
return true;
if (!(obj instanceof DNSName))
return false;
DNSName other = (DNSName)obj;
// RFC2459 mandates that these names are
// not case-sensitive
return name.equalsIgnoreCase(other.name);
}
/**
* Returns the hash code value for this object.
*
* @return a hash code value for this object.
*/
public int hashCode() {
return name.toUpperCase(Locale.ENGLISH).hashCode();
}
/**
* Return type of constraint inputName places on this name:<ul>
* <li>NAME_DIFF_TYPE = -1: input name is different type from name (i.e. does not constrain).
* <li>NAME_MATCH = 0: input name matches name.
* <li>NAME_NARROWS = 1: input name narrows name (is lower in the naming subtree)
* <li>NAME_WIDENS = 2: input name widens name (is higher in the naming subtree)
* <li>NAME_SAME_TYPE = 3: input name does not match or narrow name, but is same type.
* </ul>. These results are used in checking NameConstraints during
* certification path verification.
* <p>
* RFC2459: DNS name restrictions are expressed as foo.bar.com. Any subdomain
* satisfies the name constraint. For example, www.foo.bar.com would
* satisfy the constraint but bigfoo.bar.com would not.
* <p>
* draft-ietf-pkix-new-part1-00.txt: DNS name restrictions are expressed as foo.bar.com.
* Any DNS name that
* can be constructed by simply adding to the left hand side of the name
* satisfies the name constraint. For example, www.foo.bar.com would
* satisfy the constraint but foo1.bar.com would not.
* <p>
* RFC1034: By convention, domain names can be stored with arbitrary case, but
* domain name comparisons for all present domain functions are done in a
* case-insensitive manner, assuming an ASCII character set, and a high
* order zero bit.
* <p>
* @param inputName to be checked for being constrained
* @returns constraint type above
* @throws UnsupportedOperationException if name is not exact match, but narrowing and widening are
* not supported for this name type.
*/
public int constrains(GeneralNameInterface inputName) throws UnsupportedOperationException {
int constraintType;
if (inputName == null)
constraintType = NAME_DIFF_TYPE;
else if (inputName.getType() != NAME_DNS)
constraintType = NAME_DIFF_TYPE;
else {
String inName =
(((DNSName)inputName).getName()).toLowerCase(Locale.ENGLISH);
String thisName = name.toLowerCase(Locale.ENGLISH);
if (inName.equals(thisName))
constraintType = NAME_MATCH;
else if (thisName.endsWith(inName)) {
int inNdx = thisName.lastIndexOf(inName);
if (thisName.charAt(inNdx-1) == '.' )
constraintType = NAME_WIDENS;
else
constraintType = NAME_SAME_TYPE;
} else if (inName.endsWith(thisName)) {
int ndx = inName.lastIndexOf(thisName);
if (inName.charAt(ndx-1) == '.' )
constraintType = NAME_NARROWS;
else
constraintType = NAME_SAME_TYPE;
} else {
constraintType = NAME_SAME_TYPE;
}
}
return constraintType;
}
/**
* Return subtree depth of this name for purposes of determining
* NameConstraints minimum and maximum bounds and for calculating
* path lengths in name subtrees.
*
* @returns distance of name from root
* @throws UnsupportedOperationException if not supported for this name type
*/
public int subtreeDepth() throws UnsupportedOperationException {
String subtree=name;
int i=1;
/* count dots */
for (; subtree.lastIndexOf('.') >= 0; i++) {
subtree=subtree.substring(0,subtree.lastIndexOf('.'));
}
return i;
}
}