File	Doc	Category	Size	Date	Package
FacebookSignatureUtil.java	API Doc	Google Facebook API v1.4	11844	Tue Oct 23 20:32:32 BST 2007	com.facebook.api

FacebookSignatureUtil

• java.lang.Object

Fields Summary

Constructors Summary
private FacebookSignatureUtil()

Methods Summary
public static java.util.List	convert(java.util.Collection entries) Converts a Map of key-value pairs into the form expected by generateSignature param entries a collection of Map.Entry's, such as can be obtained using myMap.entrySet() return a List suitable for being passed to generateSignature List<String> result = new ArrayList<String>(entries.size()); for (Map.Entry<String, CharSequence> entry: entries) result.add(FacebookParam.stripSignaturePrefix(entry.getKey()) + "=" + entry.getValue()); return result;
public static java.util.List	convertFacebookParams(java.util.Collection entries) Converts a Map of key-value pairs into the form expected by generateSignature param entries a collection of Map.Entry's, such as can be obtained using myMap.entrySet() return a List suitable for being passed to generateSignature List<String> result = new ArrayList<String>(entries.size()); for (Map.Entry<FacebookParam, CharSequence> entry: entries) result.add(entry.getKey().getSignatureName() + "=" + entry.getValue()); return result;
public static java.util.Map	extractFacebookNamespaceParams(java.util.Map reqParams) Out of the passed in reqParams, extracts the parameters that are in the FacebookParam namespace and returns them. param reqParams a map of request parameters to their values return a boolean indicating whether the calculated signature matched the expected signature if (null == reqParams) return null; Map<String,CharSequence> result = new HashMap<String,CharSequence>(reqParams.size()); for (Map.Entry<CharSequence,CharSequence> entry : reqParams.entrySet()) { String key = entry.getKey().toString(); if (FacebookParam.isInNamespace(key)) result.put(key, entry.getValue()); } return result;
public static java.util.EnumMap	extractFacebookParams(java.util.Map reqParams) Out of the passed in reqParams, extracts the parameters that are known FacebookParams and returns them. param reqParams a map of request parameters to their values return a map suitable for being passed to verify signature if (null == reqParams) return null; EnumMap<FacebookParam, CharSequence> result = new EnumMap<FacebookParam, CharSequence>(FacebookParam.class); for (Map.Entry<CharSequence, CharSequence> entry: reqParams.entrySet()) { FacebookParam matchingFacebookParam = FacebookParam.get(entry.getKey().toString()); if (null != matchingFacebookParam) { result.put(matchingFacebookParam, entry.getValue()); } } return result;
public static java.util.Map	extractFacebookParamsFromArray(java.util.Map reqParams) Out of the passed in reqParams, extracts the parameters that are in the FacebookParam namespace and returns them. param reqParams A map of request parameters to their values. Values are arrays of strings, as returned by ServletRequest.getParameterMap(). Only the first element in a given array is significant. return a boolean indicating whether the calculated signature matched the expected signature if (null == reqParams) return null; Map<String,CharSequence> result = new HashMap<String,CharSequence>(reqParams.size()); for (Map.Entry<CharSequence,CharSequence[]> entry : reqParams.entrySet()) { String key = entry.getKey().toString(); if (FacebookParam.isInNamespace(key)) { CharSequence[] value = entry.getValue(); if (value.length > 0) result.put(key, value[0]); } } return result;
public static java.lang.String	generateSignature(java.util.List params, java.lang.String secret) Calculates the signature for the given set of params using the supplied secret param params Strings of the form "key=value" param secret return the signature StringBuffer buffer = new StringBuffer(); Collections.sort(params); for (String param: params) { buffer.append(param); } buffer.append(secret); try { java.security.MessageDigest md = java.security.MessageDigest.getInstance("MD5"); StringBuffer result = new StringBuffer(); for (byte b: md.digest(buffer.toString().getBytes())) { result.append(Integer.toHexString((b & 0xf0) >>> 4)); result.append(Integer.toHexString(b & 0x0f)); } return result.toString(); } catch (java.security.NoSuchAlgorithmException ex) { System.err.println("MD5 does not appear to be supported" + ex); return ""; }
public static boolean	verifySignature(java.util.EnumMap params, java.lang.String secret) Verifies that a signature received matches the expected value. Removes FacebookParam.SIGNATURE from params if present. param params a map of parameters and their values, such as one obtained from extractFacebookParams; expected to the expected signature as the FacebookParam.SIGNATURE parameter param secret return a boolean indicating whether the calculated signature matched the expected signature if (null == params || params.isEmpty() ) return false; CharSequence sigParam = params.remove(FacebookParam.SIGNATURE); return (null == sigParam) ? false : verifySignature(params, secret, sigParam.toString());
public static boolean	verifySignature(java.util.EnumMap params, java.lang.String secret, java.lang.String expected) Verifies that a signature received matches the expected value. param params a map of parameters and their values, such as one obtained from extractFacebookParams param secret the developers 'secret' API key param expected the expected resulting value of computing the MD5 sum of the 'sig' params and the 'secret' key return a boolean indicating whether the calculated signature matched the expected signature assert !(null == secret || "".equals(secret)); if (null == params || params.isEmpty() ) return false; if (null == expected || "".equals(expected)) { return false; } params.remove(FacebookParam.SIGNATURE); List<String> sigParams = convertFacebookParams(params.entrySet()); return verifySignature(sigParams, secret, expected);
public static boolean	verifySignature(java.util.Map params, java.lang.String secret) Verifies that a signature received matches the expected value. Removes FacebookParam.SIGNATURE from params if present. param params a map of parameters and their values, such as one obtained from extractFacebookNamespaceParams; expected to contain the signature as the FacebookParam.SIGNATURE parameter param secret the developers 'secret' API key return a boolean indicating whether the calculated signature matched the expected signature if (null == params || params.isEmpty() ) return false; CharSequence sigParam = params.remove(FacebookParam.SIGNATURE.toString()); return (null == sigParam) ? false : verifySignature(params, secret, sigParam.toString());
public static boolean	verifySignature(java.util.Map params, java.lang.String secret, java.lang.String expected) Verifies that a signature received matches the expected value. param params a map of parameters and their values, such as one obtained from extractFacebookNamespaceParams param secret the developers 'secret' API key param expected the expected resulting value of computing the MD5 sum of the 'sig' params and the 'secret' key return a boolean indicating whether the calculated signature matched the expected signature assert !(null == secret || "".equals(secret)); if (null == params || params.isEmpty() ) return false; if (null == expected || "".equals(expected)) { return false; } params.remove(FacebookParam.SIGNATURE.toString()); List<String> sigParams = convert(params.entrySet()); return verifySignature(sigParams, secret, expected);
private static boolean	verifySignature(java.util.List sigParams, java.lang.String secret, java.lang.String expected) if (null == expected || "".equals(expected)) return false; String signature = generateSignature(sigParams, secret); return expected.equals(signature);