Package org.apache.sshd.putty

Interface PuttyKeyPairResourceParser<PUB extends PublicKey,PRV extends PrivateKey>

Type Parameters:

PUB - Generic public key type

PRV - Generic private key type

All Superinterfaces:

IdentityResourceLoader<PUB,PRV>, KeyPairResourceLoader, KeyPairResourceParser, KeyTypeNamesSupport

All Known Implementing Classes:

AbstractPuttyKeyDecoder, DSSPuttyKeyDecoder, ECDSAPuttyKeyDecoder, EdDSAPuttyKeyDecoder, RSAPuttyKeyDecoder

public interface PuttyKeyPairResourceParser<PUB extends PublicKey,PRV extends PrivateKey>
extends IdentityResourceLoader<PUB,PRV>, KeyPairResourceParser

Loads a KeyPair from PuTTY's ".ppk" file.

Note(s):

• The file appears to be a text file but it doesn't have a fixed encoding like UTF-8. We use UTF-8 as the default encoding - since the important part is all ASCII, this shouldn't really hurt the interpretation of the key.
• Based on code from Kohsuke's Trilead Putty Extension
• Encrypted keys requires AES-256-CBC support, which is available only if the Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files are installed

Sample PuTTY file format

 PuTTY-User-Key-File-2: ssh-rsa
 Encryption: none
 Comment: rsa-key-20080514
 Public-Lines: 4
 AAAAB3NzaC1yc2EAAAABJQAAAIEAiPVUpONjGeVrwgRPOqy3Ym6kF/f8bltnmjA2
 BMdAtaOpiD8A2ooqtLS5zWYuc0xkW0ogoKvORN+RF4JI+uNUlkxWxnzJM9JLpnvA
 HrMoVFaQ0cgDMIHtE1Ob1cGAhlNInPCRnGNJpBNcJ/OJye3yt7WqHP4SPCCLb6nL
 nmBUrLM=
 Private-Lines: 8
 AAAAgGtYgJzpktzyFjBIkSAmgeVdozVhgKmF6WsDMUID9HKwtU8cn83h6h7ug8qA
 hUWcvVxO201/vViTjWVz9ALph3uMnpJiuQaaNYIGztGJBRsBwmQW9738pUXcsUXZ
 79KJP01oHn6Wkrgk26DIOsz04QOBI6C8RumBO4+F1WdfueM9AAAAQQDmA4hcK8Bx
 nVtEpcF310mKD3nsbJqARdw5NV9kCxPnEsmy7Sy1L4Ob/nTIrynbc3MA9HQVJkUz
 7V0va5Pjm/T7AAAAQQCYbnG0UEekwk0LG1Hkxh1OrKMxCw2KWMN8ac3L0LVBg/Tk
 8EnB2oT45GGeJaw7KzdoOMFZz0iXLsVLNUjNn2mpAAAAQQCN6SEfWqiNzyc/w5n/
 lFVDHExfVUJp0wXv+kzZzylnw4fs00lC3k4PZDSsb+jYCMesnfJjhDgkUA0XPyo8
 Emdk
 Private-MAC: 50c45751d18d74c00fca395deb7b7695e3ed6f77
 

Field Summary

Fields

Modifier and Type	Field	Description
static final String	KEY_FILE_HEADER_PREFIX
static final List<String>	KNOWN_HEADERS
static final String	NO_PRIVATE_KEY_ENCRYPTION_VALUE	Value (case insensitive) used to denote that private key is not encrypted
static final String	PPK_FILE_SUFFIX
static final String	PRIVATE_LINES_HEADER
static final String	PUBLIC_LINES_HEADER

Fields inherited from interface org.apache.sshd.common.config.keys.IdentityResourceLoader

MAX_BIGINT_OCTETS_COUNT

Fields inherited from interface org.apache.sshd.common.config.keys.loader.KeyPairResourceLoader

MAX_CIPHER_NAME_LENGTH, MAX_KEY_COMMENT_LENGTH, MAX_KEY_TYPE_NAME_LENGTH, MAX_PRIVATE_KEY_DATA_SIZE, MAX_PUBLIC_KEY_DATA_SIZE

Fields inherited from interface org.apache.sshd.common.config.keys.loader.KeyPairResourceParser

EMPTY

Method Summary

Modifier and Type	Method	Description
default boolean	canExtractKeyPairs(NamedResource resourceKey, List<String> lines)
static byte[]	decodePrivateKeyBytes(byte[] prvBytes, String algName, int numBits, String algMode, String password)
static byte[]	decodePrivateKeyBytes(byte[] encBytes, String cipherName, String cipherMode, int numBits, byte[] initVector, byte[] keyValue)
static byte[]	toEncryptionKey(String passphrase)	Converts a pass-phrase into a key, by following the convention that PuTTY uses.

Methods inherited from interface org.apache.sshd.common.config.keys.IdentityResourceLoader

getPrivateKeyType, getPublicKeyType

Methods inherited from interface org.apache.sshd.common.config.keys.loader.KeyPairResourceLoader

loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs, loadKeyPairs

Methods inherited from interface org.apache.sshd.common.config.keys.KeyTypeNamesSupport

getSupportedKeyTypes

Field Details

KEY_FILE_HEADER_PREFIX

static final String KEY_FILE_HEADER_PREFIX

See Also:

• Constant Field Values

PUBLIC_LINES_HEADER

static final String PUBLIC_LINES_HEADER

See Also:

• Constant Field Values

PRIVATE_LINES_HEADER

static final String PRIVATE_LINES_HEADER

See Also:

• Constant Field Values

PPK_FILE_SUFFIX

static final String PPK_FILE_SUFFIX

See Also:

• Constant Field Values

KNOWN_HEADERS

static final List<String> KNOWN_HEADERS

NO_PRIVATE_KEY_ENCRYPTION_VALUE

static final String NO_PRIVATE_KEY_ENCRYPTION_VALUE

Value (case insensitive) used to denote that private key is not encrypted

See Also:

• Constant Field Values

Method Details

canExtractKeyPairs

default boolean canExtractKeyPairs(NamedResource resourceKey,
 List<String> lines)
                            throws IOException,
GeneralSecurityException

Specified by:

canExtractKeyPairs in interface KeyPairResourceParser

Parameters:

resourceKey - A hint as to the origin of the text lines

lines - The resource lines

Returns:

true if the parser can extract some key pairs from the lines

Throws:

IOException - If failed to process the lines

GeneralSecurityException - If failed to extract information regarding the possibility to extract the key pairs

decodePrivateKeyBytes

static byte[] decodePrivateKeyBytes(byte[] prvBytes,
 String algName,
 int numBits,
 String algMode,
 String password)
                             throws GeneralSecurityException

Throws:

GeneralSecurityException

decodePrivateKeyBytes

static byte[] decodePrivateKeyBytes(byte[] encBytes,
 String cipherName,
 String cipherMode,
 int numBits,
 byte[] initVector,
 byte[] keyValue)
                             throws GeneralSecurityException

Throws:

GeneralSecurityException

toEncryptionKey

static byte[] toEncryptionKey(String passphrase)
                       throws GeneralSecurityException

Converts a pass-phrase into a key, by following the convention that PuTTY uses. Used to decrypt the private key when it's encrypted.

Parameters:

passphrase - the Password to be used as seed for the key - ignored if null/empty

Returns:

The encryption key bytes - null/empty if no pass-phrase

Throws:

GeneralSecurityException - If cannot retrieve SHA-1 digest

See Also:

• How does Putty derive the encryption key in its .ppk format ?