@Override
public void doHandshake(NextFilter nextFilter) throws ProxyAuthException {
logger.debug(" doHandshake()");
if (step > 0 && directives == null) {
throw new ProxyAuthException(
"Authentication challenge not received");
} else {
HttpProxyRequest req = (HttpProxyRequest) request;
Map<String, List<String>> headers = req.getHeaders() != null ? req
.getHeaders() : new HashMap<String, List<String>>();
if (step > 0) {
logger.debug(" sending DIGEST challenge response");
HashMap<String, String> map = new HashMap<String, String>();
map.put("username", req.getProperties().get(
HttpProxyConstants.USER_PROPERTY));
StringUtilities.copyDirective(directives, map, "realm");
StringUtilities.copyDirective(directives, map, "uri");
StringUtilities.copyDirective(directives, map, "opaque");
StringUtilities.copyDirective(directives, map, "nonce");
String algorithm = StringUtilities.copyDirective(directives,
map, "algorithm");
// Check for a supported algorithm
if (algorithm != null && !"md5".equalsIgnoreCase(algorithm)
&& !"md5-sess".equalsIgnoreCase(algorithm)) {
throw new ProxyAuthException(
"Unknown algorithm required by server");
}
// Check for a supported qop
String qop = directives.get("qop");
if (qop != null) {
StringTokenizer st = new StringTokenizer(qop, ",");
String token = null;
while (st.hasMoreTokens()) {
String tk = st.nextToken();
if ("auth".equalsIgnoreCase(token)) {
break;
} else {
int pos = Arrays.binarySearch(
DigestUtilities.SUPPORTED_QOPS, tk);
if (pos > -1) {
token = tk;
}
}
}
if (token != null) {
map.put("qop", token);
byte[] nonce = new byte[8];
rnd.nextBytes(nonce);
try {
String cnonce = new String(Base64
.encodeBase64(nonce), proxyIoSession
.getCharsetName());
map.put("cnonce", cnonce);
} catch (UnsupportedEncodingException e) {
throw new ProxyAuthException(
"Unable to encode cnonce", e);
}
} else {
throw new ProxyAuthException(
"No supported qop option available");
}
}
map.put("nc", "00000001");
map.put("uri", req.getHttpURI());
// Compute the response
try {
map.put("response", DigestUtilities
.computeResponseValue(proxyIoSession.getSession(),
map, req.getHttpVerb().toUpperCase(),
req.getProperties().get(
HttpProxyConstants.PWD_PROPERTY),
proxyIoSession.getCharsetName(), response
.getBody()));
} catch (Exception e) {
throw new ProxyAuthException(
"Digest response computing failed", e);
}
// Prepare the challenge response header and add it to the request we will send
StringBuilder sb = new StringBuilder("Digest ");