Module org.shredzone.acme4j

Package org.shredzone.acme4j.toolbox

Class AcmeUtils

java.lang.Object

org.shredzone.acme4j.toolbox.AcmeUtils

public final class AcmeUtils
extends Object

Contains utility methods that are frequently used for the ACME protocol.

This class is internal. You may use it in your own code, but be warned that methods may change their signature or disappear without prior announcement.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AcmeUtils.PemLabel	Enumeration of PEM labels.

Method Summary

Modifier and Type	Method	Description
static byte[]	base64UrlDecode(String base64)	Base64 decodes to a byte array, using URL style encoding.
static String	base64UrlEncode(byte[] data)	Base64 encodes the given byte array, using URL style encoding.
static String	getContentType(String header)	Extracts the content type of a Content-Type header.
static String	getRenewalUniqueIdentifier(X509Certificate certificate)	Returns the certificate's unique identifier for renewal according to draft-ietf-acme-ari-03.
static String	hexEncode(byte[] data)	Hex encodes the given byte array.
static boolean	isValidBase64Url(String base64)	Validates that the given String is a valid base64url encoded value.
static String	localeToLanguageHeader(Locale locale)	Converts the given locale to an Accept-Language header value.
static Instant	parseTimestamp(String str)	Parses a RFC 3339 formatted date.
static byte[]	sha256hash(String z)	Computes a SHA-256 hash of the given string.
static String	stripErrorPrefix(String type)	Strips the acme error prefix from the error string.
static String	toAce(String domain)	ASCII encodes a domain name.
static void	validateContact(URI contact)	Validates a contact URI.
static void	writeToPem(byte[] encoded, AcmeUtils.PemLabel label, Writer out)	Writes an encoded key or certificate to a file in PEM format.

Methods inherited from class java.lang.Object

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

Method Detail

sha256hash

public static byte[] sha256hash(String z)

Computes a SHA-256 hash of the given string.

Parameters:

z - String to hash

Returns:

Hash

hexEncode

public static String hexEncode(byte[] data)

Hex encodes the given byte array.

Parameters:

data - byte array to hex encode

Returns:

Hex encoded string of the data (with lower case characters)

base64UrlEncode

public static String base64UrlEncode(byte[] data)

Base64 encodes the given byte array, using URL style encoding.

Parameters:

data - byte array to base64 encode

Returns:

base64 encoded string

base64UrlDecode

public static byte[] base64UrlDecode(String base64)

Base64 decodes to a byte array, using URL style encoding.

Parameters:

base64 - base64 encoded string

Returns:

decoded data

isValidBase64Url

public static boolean isValidBase64Url(@Nullable
                                       String base64)

Validates that the given String is a valid base64url encoded value.

Parameters:

base64 - String to validate

Returns:

true: String contains a valid base64url encoded value. false if the String was null or contained illegal characters.

Since:

2.6

toAce

public static String toAce(String domain)

ASCII encodes a domain name.

The conversion is done as described in RFC 3490. Additionally, all leading and trailing white spaces are trimmed, and the result is lowercased.

It is safe to pass in ACE encoded domains, they will be returned unchanged.

Parameters:

domain - Domain name to encode

Returns:

Encoded domain name, white space trimmed and lower cased.

parseTimestamp

public static Instant parseTimestamp(String str)

Parses a RFC 3339 formatted date.

Parameters:

str - Date string

Returns:

Instant that was parsed

Throws:

IllegalArgumentException - if the date string was not RFC 3339 formatted

See Also:

RFC 3339

localeToLanguageHeader

public static String localeToLanguageHeader(@Nullable
                                            Locale locale)

Converts the given locale to an Accept-Language header value.

Parameters:

locale - Locale to be used in the header

Returns:

Value that can be used in an Accept-Language header

stripErrorPrefix

@Nullable
public static String stripErrorPrefix(@Nullable
                                      String type)

Strips the acme error prefix from the error string.

For example, for "urn:ietf:params:acme:error:unauthorized", "unauthorized" is returned.

Parameters:

type - Error type to strip the prefix from. null is safe.

Returns:

Stripped error type, or null if the prefix was not found.

writeToPem

public static void writeToPem(byte[] encoded,
                              AcmeUtils.PemLabel label,
                              Writer out)
                       throws IOException

Writes an encoded key or certificate to a file in PEM format.

Parameters:

encoded - Encoded data to write

label - AcmeUtils.PemLabel to be used

out - Writer to write to. It will not be closed after use!

Throws:

IOException

getContentType

@Nullable
public static String getContentType(@Nullable
                                    String header)

Extracts the content type of a Content-Type header.

Parameters:

header - Content-Type header

Returns:

Content-Type, or null if the header was invalid or empty

Throws:

AcmeProtocolException - if the Content-Type header contains a different charset than "utf-8".

validateContact

public static void validateContact(URI contact)

Validates a contact URI.

Parameters:

contact - Contact URI to validate

Throws:

IllegalArgumentException - if the contact URI is not suitable for account contacts.

getRenewalUniqueIdentifier

public static String getRenewalUniqueIdentifier(X509Certificate certificate)

Returns the certificate's unique identifier for renewal according to draft-ietf-acme-ari-03.

Parameters:

certificate - Certificate to get the unique identifier for.

Returns:

Unique identifier

Throws:

AcmeProtocolException - if the certificate is invalid or does not provide the necessary information.