org.tsugi.lti13

Class LTI13Util

java.lang.Object

org.tsugi.lti13.LTI13Util

public class LTI13Util
extends Object

Constructor Summary

Constructors

Constructor and Description
LTI13Util()

Method Summary

Modifier and Type	Method and Description
static void	addCustomToLaunch(Properties ltiProps, Properties custom)
static String	base64Encode(byte[] input)
static String	breakKeyIntoLines(String rawkey)
static boolean	checkLTI11Transition(LaunchJWT lj, String key, String secret) Check the OAuth signature for an LTI 1.3 Launch JWT See: https://www.imsglobal.org/spec/lti/v1p3/migr#lti-1-1-migration-claim
static String	compute_HMAC_SHA256(String message, String secret) Compute the HMAC256 of a string (part of LTI 1.1 Transition) See: https://www.imsglobal.org/spec/lti/v1p3/migr#lti-1-1-migration-claim Based on: https://www.jokecamp.com/blog/examples-of-creating-base64-hashes-using-hmac-sha256-in-different-languages/#php https://stackoverflow.com/questions/7124735/hmac-sha256-algorithm-for-signature-calculation
static KeyPair	generateKeyPair()
static Map<String,String>	generateKeys()
static Double	getDoubleNull(Object key)
static int	getInt(Object o)
static String	getKeyB64(Key key)
static Long	getLong(Object key)
static Long	getLongKey(Object key)
static Long	getLongNull(Object key)
static String	getLTI11TransitionBase(LaunchJWT lj) Compute the base string for a Launch JWT See: https://www.imsglobal.org/spec/lti/v1p3/migr#lti-1-1-migration-claim
static String	getPrivateB64(Key key)
static String	getPrivateB64(KeyPair kp)
static String	getPrivateEncoded(Key key)
static String	getPrivateEncoded(KeyPair kp)
static String	getPrivateEncoded(String keyStr)
static String	getPublicB64(KeyPair kp)
static String	getPublicEncoded(Key key)
static String	getPublicEncoded(KeyPair kp)
static String	getPublicEncoded(String keyStr)
static String	getStringNull(Object value)
static void	return400(javax.servlet.http.HttpServletResponse response, String error)
static void	return400(javax.servlet.http.HttpServletResponse response, String error, String detail)
static void	setProperty(Properties props, String key, String value)
static String	sha256(String input)
static String	signLTI11Transition(LaunchJWT lj, String secret) Compute the OAuth signature for an LTI 1.3 Launch JWT See: https://www.imsglobal.org/spec/lti/v1p3/migr#lti-1-1-migration-claim
static Key	string2PrivateKey(String keyString)
static Key	string2PublicKey(String keyString)
static KeyPair	strings2KeyPair(String pubKeyStr, String privKeyStr)
static String	stripPKCS8(String input)
static void	substituteCustom(Properties custom, Properties lti2subst)
static String	timeStamp(String token) timeStamp - Add a time-stamp to the beginning of a string
static boolean	timeStampCheck(String token, int seconds) timeStampCheck - Check a time-stamp at the beginning of a string
static boolean	timeStampCheckSign(String token, String secret, int seconds) timeStampCheckSign - check to see if a token has not expired and is signed
static String	timeStampSign(String token, String secret) timeStampSign - Take a one-time token and add a timestamp timestamp:token:signature
static String	toNull(String str)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

LTI13Util

public LTI13Util()

Method Detail

generateKeys

public static Map<String,String> generateKeys()
                                       throws NoSuchAlgorithmException

Throws:

NoSuchAlgorithmException

base64Encode

public static String base64Encode(byte[] input)

stripPKCS8

public static String stripPKCS8(String input)

generateKeyPair

public static KeyPair generateKeyPair()

getKeyB64

public static String getKeyB64(Key key)

getPublicB64

public static String getPublicB64(KeyPair kp)

getPublicEncoded

public static String getPublicEncoded(KeyPair kp)

getPublicEncoded

public static String getPublicEncoded(Key key)

getPublicEncoded

public static String getPublicEncoded(String keyStr)

getPrivateB64

public static String getPrivateB64(KeyPair kp)

getPrivateB64

public static String getPrivateB64(Key key)

getPrivateEncoded

public static String getPrivateEncoded(KeyPair kp)

getPrivateEncoded

public static String getPrivateEncoded(Key key)

getPrivateEncoded

public static String getPrivateEncoded(String keyStr)

breakKeyIntoLines

public static String breakKeyIntoLines(String rawkey)

string2PrivateKey

public static Key string2PrivateKey(String keyString)

string2PublicKey

public static Key string2PublicKey(String keyString)

strings2KeyPair

public static KeyPair strings2KeyPair(String pubKeyStr,
                                      String privKeyStr)

getLTI11TransitionBase

public static String getLTI11TransitionBase(LaunchJWT lj)

Compute the base string for a Launch JWT See: https://www.imsglobal.org/spec/lti/v1p3/migr#lti-1-1-migration-claim

Parameters:

lj - The Launch JSON Web Token with the LTI 1.1 transition data

Returns:

string This is null if the base string cannot be computed

signLTI11Transition

public static String signLTI11Transition(LaunchJWT lj,
                                         String secret)

Compute the OAuth signature for an LTI 1.3 Launch JWT See: https://www.imsglobal.org/spec/lti/v1p3/migr#lti-1-1-migration-claim

Parameters:

lj - The Launch JSON Web Token with the LTI 11 transition data

secret - The OAuth secret

Returns:

string This is null if the signature cannot be computed

checkLTI11Transition

public static boolean checkLTI11Transition(LaunchJWT lj,
                                           String key,
                                           String secret)

Check the OAuth signature for an LTI 1.3 Launch JWT See: https://www.imsglobal.org/spec/lti/v1p3/migr#lti-1-1-migration-claim

Parameters:

lj - The Launch JSON Web Token with the LTI 11 transition data

key - The OAuth key

secret - The OAuth secret

Returns:

true if the signature matches, false if the JWT the signature does not match or the JWT data is malformed.

sha256

public static String sha256(String input)

compute_HMAC_SHA256

public static String compute_HMAC_SHA256(String message,
                                         String secret)

Compute the HMAC256 of a string (part of LTI 1.1 Transition) See: https://www.imsglobal.org/spec/lti/v1p3/migr#lti-1-1-migration-claim Based on: https://www.jokecamp.com/blog/examples-of-creating-base64-hashes-using-hmac-sha256-in-different-languages/#php https://stackoverflow.com/questions/7124735/hmac-sha256-algorithm-for-signature-calculation

Parameters:

object - $message The message to sign

string - $secret The secret used to sign the message

Returns:

string The signed message

return400

public static void return400(javax.servlet.http.HttpServletResponse response,
                             String error,
                             String detail)

return400

public static void return400(javax.servlet.http.HttpServletResponse response,
                             String error)

substituteCustom

public static void substituteCustom(Properties custom,
                                    Properties lti2subst)

addCustomToLaunch

public static void addCustomToLaunch(Properties ltiProps,
                                     Properties custom)

setProperty

public static void setProperty(Properties props,
                               String key,
                               String value)

timeStamp

public static String timeStamp(String token)

timeStamp - Add a time-stamp to the beginning of a string

timeStampCheck

public static boolean timeStampCheck(String token,
                                     int seconds)

timeStampCheck - Check a time-stamp at the beginning of a string

timeStampSign

public static String timeStampSign(String token,
                                   String secret)

timeStampSign - Take a one-time token and add a timestamp timestamp:token:signature

timeStampCheckSign

public static boolean timeStampCheckSign(String token,
                                         String secret,
                                         int seconds)

timeStampCheckSign - check to see if a token has not expired and is signed

toNull

public static String toNull(String str)

getInt

public static int getInt(Object o)

getLongKey

public static Long getLongKey(Object key)

getLong

public static Long getLong(Object key)

getLongNull

public static Long getLongNull(Object key)

getDoubleNull

public static Double getDoubleNull(Object key)

getStringNull

public static String getStringNull(Object value)