/** Default constructor. */
public DigestServerAuthenticationMethod() {
try {
messageDigest = MessageDigest.getInstance(DEFAULT_ALGORITHM);
} catch (NoSuchAlgorithmException ex) {
ProxyDebug.println("Algorithm not found " + ex);
ex.printStackTrace();
}
passwordTable = new Hashtable();
}
/**
* Generate the challenge string.
*
* @return a generated nonce.
*/
public String generateNonce() {
// Get the time of day and run MD5 over it.
Date date = new Date();
long time = date.getTime();
Random rand = new Random();
long pad = rand.nextLong();
String nonceString = (new Long(time)).toString() + (new Long(pad)).toString();
byte mdbytes[] = messageDigest.digest(nonceString.getBytes());
// Convert the mdbytes array into a hex string.
return ProxyUtilities.toHexString(mdbytes);
}
/**
* Check the response and answer true if authentication succeeds. We are making simplifying
* assumptions here and assuming that the password is available to us for computation of the MD5
* hash. We also dont cache authentications so that the user has to authenticate on each
* registration.
*
* @param user is the username
* @param authHeader is the Authroization header from the SIP request.
* @param requestLine is the SIP Request line from the SIP request.
* @exception SIPAuthenticationException is thrown when authentication fails or message is bad
*/
public boolean doAuthenticate(String user, AuthorizationHeader authHeader, Request request) {
String realm = authHeader.getRealm();
String username = authHeader.getUsername();
URI requestURI = request.getRequestURI();
if (username == null) {
ProxyDebug.println(
"DEBUG, DigestAuthenticateMethod, doAuthenticate(): "
+ "WARNING: userName parameter not set in the header received!!!");
username = user;
}
if (realm == null) {
ProxyDebug.println(
"DEBUG, DigestAuthenticateMethod, doAuthenticate(): "
+ "WARNING: realm parameter not set in the header received!!! WE use the default one");
realm = DEFAULT_REALM;
}
ProxyDebug.println(
"DEBUG, DigestAuthenticateMethod, doAuthenticate(): "
+ "Trying to authenticate user: "******" for "
+ " the realm: "
+ realm);
String password = (String) passwordTable.get(username + "@" + realm);
if (password == null) {
ProxyDebug.println(
"DEBUG, DigestAuthenticateMethod, doAuthenticate(): "
+ "ERROR: password not found for the user: "******"@"
+ realm);
return false;
}
String nonce = authHeader.getNonce();
// If there is a URI parameter in the Authorization header,
// then use it.
URI uri = authHeader.getURI();
// There must be a URI parameter in the authorization header.
if (uri == null) {
ProxyDebug.println(
"DEBUG, DigestAuthenticateMethod, doAuthenticate(): "
+ "ERROR: uri paramater not set in the header received!");
return false;
}
ProxyDebug.println(
"DEBUG, DigestAuthenticationMethod, doAuthenticate(), username:"******"!");
ProxyDebug.println("DEBUG, DigestAuthenticationMethod, doAuthenticate(), realm:" + realm + "!");
ProxyDebug.println(
"DEBUG, DigestAuthenticationMethod, doAuthenticate(), password:"******"!");
ProxyDebug.println("DEBUG, DigestAuthenticationMethod, doAuthenticate(), uri:" + uri + "!");
ProxyDebug.println("DEBUG, DigestAuthenticationMethod, doAuthenticate(), nonce:" + nonce + "!");
ProxyDebug.println(
"DEBUG, DigestAuthenticationMethod, doAuthenticate(), method:" + request.getMethod() + "!");
String A1 = username + ":" + realm + ":" + password;
String A2 = request.getMethod().toUpperCase() + ":" + uri.toString();
byte mdbytes[] = messageDigest.digest(A1.getBytes());
String HA1 = ProxyUtilities.toHexString(mdbytes);
ProxyDebug.println("DEBUG, DigestAuthenticationMethod, doAuthenticate(), HA1:" + HA1 + "!");
mdbytes = messageDigest.digest(A2.getBytes());
String HA2 = ProxyUtilities.toHexString(mdbytes);
ProxyDebug.println("DEBUG, DigestAuthenticationMethod, doAuthenticate(), HA2:" + HA2 + "!");
String cnonce = authHeader.getCNonce();
String KD = HA1 + ":" + nonce;
if (cnonce != null) {
KD += ":" + cnonce;
}
KD += ":" + HA2;
mdbytes = messageDigest.digest(KD.getBytes());
String mdString = ProxyUtilities.toHexString(mdbytes);
String response = authHeader.getResponse();
ProxyDebug.println(
"DEBUG, DigestAuthenticateMethod, doAuthenticate(): "
+ "we have to compare his response: "
+ response
+ " with our computed"
+ " response: "
+ mdString);
int res = (mdString.compareTo(response));
if (res == 0) {
ProxyDebug.println(
"DEBUG, DigestAuthenticateMethod, doAuthenticate(): " + "User authenticated...");
} else {
ProxyDebug.println(
"DEBUG, DigestAuthenticateMethod, doAuthenticate(): " + "User not authenticated...");
}
return res == 0;
}
