/*
* Conditions Of Use
*
* This software was developed by employees of the National Institute of
* Standards and Technology (NIST), an agency of the Federal Government.
* Pursuant to title 15 Untied States Code Section 105, works of NIST
* employees are not subject to copyright protection in the United States
* and are considered to be in the public domain. As a result, a formal
* license is not needed to use the software.
*
* This software is provided by NIST as a service and is expressly
* provided "AS IS." NIST MAKES NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED
* OR STATUTORY, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTY OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT
* AND DATA ACCURACY. NIST does not warrant or make any representations
* regarding the use of the software or the results thereof, including but
* not limited to the correctness, accuracy, reliability or usefulness of
* the software.
*
* Permission to use this software is contingent upon your acceptance
* of the terms of this agreement
*
* .
*
*/
/*
*
* IPv6 Support added by Emil Ivov (emil_ivov@yahoo.com)<br/>
* Network Research Team (http://www-r2.u-strasbg.fr))<br/>
* Louis Pasteur University - Strasbourg - France<br/>
*
*Bug fixes for corner cases were contributed by Thomas Froment.
*/
package gov.nist.core;
// BEGIN android-deleted
//import gov.nist.javax.sdp.parser.Lexer;
// END android-deleted
import java.text.ParseException;
/**
* Parser for host names.
*
*@version 1.2
*
*@author M. Ranganathan
*/
public class HostNameParser extends ParserCore {
// BEGIN android-added
private static LexerCore Lexer;
// END android-added
/**
* Determines whether or not we should tolerate and strip address scope
* zones from IPv6 addresses. Address scope zones are sometimes returned
* at the end of IPv6 addresses generated by InetAddress.getHostAddress().
* They are however not part of the SIP semantics so basically this method
* determines whether or not the parser should be stripping them (as
* opposed simply being blunt and throwing an exception).
*/
private boolean stripAddressScopeZones = false;
public HostNameParser(String hname) {
this.lexer = new LexerCore("charLexer", hname);
stripAddressScopeZones
= Boolean.getBoolean("gov.nist.core.STRIP_ADDR_SCOPES");
}
/**
* The lexer is initialized with the buffer.
*/
public HostNameParser(LexerCore lexer) {
this.lexer = lexer;
lexer.selectLexer("charLexer");
stripAddressScopeZones
= Boolean.getBoolean("gov.nist.core.STRIP_ADDR_SCOPES");
}
private static final char[] VALID_DOMAIN_LABEL_CHAR =
new char[] {LexerCore.ALPHADIGIT_VALID_CHARS, '-', '.'};
protected void consumeDomainLabel() throws ParseException {
if (debug)
dbg_enter("domainLabel");
try {
lexer.consumeValidChars(VALID_DOMAIN_LABEL_CHAR);
} finally {
if (debug)
dbg_leave("domainLabel");
}
}
protected String ipv6Reference() throws ParseException {
StringBuffer retval = new StringBuffer();
if (debug)
dbg_enter("ipv6Reference");
try {
if(stripAddressScopeZones){
while (lexer.hasMoreChars()) {
char la = lexer.lookAhead(0);
//'%' is ipv6 address scope zone. see detail at
//java.sun.com/j2se/1.5.0/docs/api/java/net/Inet6Address.html
if (LexerCore.isHexDigit(la) || la == '.' || la == ':'
|| la == '[' ) {
lexer.consume(1);
retval.append(la);
} else if (la == ']') {
lexer.consume(1);
retval.append(la);
return retval.toString();
} else if (la == '%'){
//we need to strip the address scope zone.
lexer.consume(1);
String rest = lexer.getRest();
if(rest == null || rest.length() == 0){
//head for the parse exception
break;
}
//we strip everything until either the end of the string
//or a closing square bracket (])
int stripLen = rest.indexOf(']');
if (stripLen == -1){
//no square bracket -> not a valid ipv6 reference
break;
}
lexer.consume(stripLen+1);
retval.append("]");
return retval.toString();
} else
break;
}
}
else
{
while (lexer.hasMoreChars())
{
char la = lexer.lookAhead(0);
if (LexerCore.isHexDigit(la) || la == '.'
|| la == ':' || la == '[') {
lexer.consume(1);
retval.append(la);
} else if (la == ']') {
lexer.consume(1);
retval.append(la);
return retval.toString();
} else
break;
}
}
throw new ParseException(
lexer.getBuffer() + ": Illegal Host name ",
lexer.getPtr());
} finally {
if (debug)
dbg_leave("ipv6Reference");
}
}
public Host host() throws ParseException {
if (debug)
dbg_enter("host");
try {
String hostname;
//IPv6 referene
if (lexer.lookAhead(0) == '[') {
hostname = ipv6Reference();
}
//IPv6 address (i.e. missing square brackets)
else if( isIPv6Address(lexer.getRest()) )
{
int startPtr = lexer.getPtr();
lexer.consumeValidChars(
new char[] {LexerCore.ALPHADIGIT_VALID_CHARS, ':'});
hostname
= new StringBuffer("[").append(
lexer.getBuffer().substring(startPtr, lexer.getPtr()))
.append("]").toString();
}
//IPv4 address or hostname
else {
int startPtr = lexer.getPtr();
consumeDomainLabel();
hostname = lexer.getBuffer().substring(startPtr, lexer.getPtr());
}
if (hostname.length() == 0)
throw new ParseException(
lexer.getBuffer() + ": Missing host name",
lexer.getPtr());
else
return new Host(hostname);
} finally {
if (debug)
dbg_leave("host");
}
}
/**
* Tries to determine whether the address in <tt>uriHeader</tt> could be
* an IPv6 address by counting the number of colons that appear in it.
*
* @param uriHeader the string (supposedly the value of a URI header) that
* we have received for parsing.
*
* @return true if the host part of <tt>uriHeader</tt> could be an IPv6
* address (i.e. contains at least two colons) and false otherwise.
*/
private boolean isIPv6Address(String uriHeader)
{
// approximately detect the end the host part.
//first check if we have an uri param
int hostEnd = uriHeader.indexOf(Lexer.QUESTION);
//if not or if it appears after a semi-colon then the end of the
//address would be a header param.
int semiColonIndex = uriHeader.indexOf(Lexer.SEMICOLON);
if ( hostEnd == -1
|| (semiColonIndex!= -1 && hostEnd > semiColonIndex) )
hostEnd = semiColonIndex;
//if there was no header param either the address
//continues until the end of the string
if ( hostEnd == -1 )
hostEnd = uriHeader.length();
//extract the address
String host = uriHeader.substring(0, hostEnd);
int firstColonIndex = host.indexOf(Lexer.COLON);
if(firstColonIndex == -1)
return false;
int secondColonIndex = host.indexOf(Lexer.COLON, firstColonIndex + 1);
if(secondColonIndex == -1)
return false;
return true;
}
/**
* Parses a host:port string
*
* @param allowWS - whether whitespace is allowed around ':', only true for Via headers
* @return
* @throws ParseException
*/
public HostPort hostPort( boolean allowWS ) throws ParseException {
if (debug)
dbg_enter("hostPort");
try {
Host host = this.host();
HostPort hp = new HostPort();
hp.setHost(host);
// Has a port?
if (allowWS) lexer.SPorHT(); // white space before ":port" should be accepted
if (lexer.hasMoreChars()) {
char la = lexer.lookAhead(0);
switch (la)
{
case ':':
lexer.consume(1);
if (allowWS) lexer.SPorHT(); // white space before port number should be accepted
try {
String port = lexer.number();
hp.setPort(Integer.parseInt(port));
} catch (NumberFormatException nfe) {
throw new ParseException(
lexer.getBuffer() + " :Error parsing port ",
lexer.getPtr());
}
break;
case ',': // allowed in case of multi-headers, e.g. Route
// Could check that current header is a multi hdr
case ';': // OK, can appear in URIs (parameters)
case '?': // same, header parameters
case '>': // OK, can appear in headers
case ' ': // OK, allow whitespace
case '\t':
case '\r':
case '\n':
case '/': // e.g. http://[::1]/xyz.html
break;
case '%':
if(stripAddressScopeZones){
break;//OK,allow IPv6 address scope zone
}
default:
if (!allowWS) {
throw new ParseException( lexer.getBuffer() +
" Illegal character in hostname:" + lexer.lookAhead(0),
lexer.getPtr() );
}
}
}
return hp;
} finally {
if (debug)
dbg_leave("hostPort");
}
}
public static void main(String args[]) throws ParseException {
String hostNames[] =
{
"foo.bar.com:1234",
"proxima.chaplin.bt.co.uk",
"129.6.55.181:2345",
":1234",
"foo.bar.com: 1234",
"foo.bar.com : 1234 ",
"MIK_S:1234"
};
for (int i = 0; i < hostNames.length; i++) {
try {
HostNameParser hnp = new HostNameParser(hostNames[i]);
HostPort hp = hnp.hostPort(true);
System.out.println("["+hp.encode()+"]");
} catch (ParseException ex) {
System.out.println("exception text = " + ex.getMessage());
}
}
}
}