(mozilla-projects-nss-jss-jss-provider-notes)=

# JSS Provider Notes

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This page has been moved to <http://www.dogtagpki.org/wiki/JSS_Provider>.
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## [The Mozilla-JSS JCA Provider](#the_mozilla-jss_jca_provider)

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Newsgroup: [mozilla.dev.tech.crypto](news://news.mozilla.org/mozilla.dev.tech.crypto)
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### [Overview](#overview)

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This document describes the JCA Provider shipped with JSS. The provider's name is "Mozilla-JSS".
It implements cryptographic operations in native code using the [NSS](../nss) libraries.
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### [Contents](#contents)

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- [Signed JAR file](#signed-jar)
- [Installing the Provider](#installing-provider)
- [Specifying the CryptoToken](#specifying-token)
- [Supported Classes](#supported-classes)
- [What's Not Supported](#not-supported)
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### [Signed JAR file](#signed_jar_file)

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- JSS 3.2 implements several JCE (Java Cryptography Extension) algorithms. These algorithms have
  at various times been export-controlled by the US government. Sun therefore requires that JAR
  files implementing JCE algorithms be digitally signed by an approved organization. Netscape
  has this approval and signs the official builds of `jss32.jar`. At runtime, the JRE
  automatically verifies this signature whenever a JSS class is loaded that implements a JCE
  algorithm. The verification is transparent to the application (unless it fails and throws an
  exception). If you are curious, you can verify the signature on the JAR file using the
  `jarsigner` tool, which is distributed with the JDK.

  If you build JSS yourself from source instead of using binaries downloaded from mozilla.org,
  your JAR file will not have a valid signature. This means you will not be able to use the JSS
  provider for JCE algorithms. You have two choices.

  1. Use the binary release of JSS from mozilla.org.
  2. Apply for your own JCE code-signing certificate following the procedure at [How to
     Implement a Provider for the JavaTM Cryptography
     Extension](http://java.sun.com/javase/6/docs/technotes/guides/security/crypto/HowToImplAProvider.html#Step61).
     Then you can sign your own JSS JAR file.
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### [Installing the Provider](#installing_the_provider)

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- In order to use any part of JSS, including the JCA provider, you must first call
  `CryptoManager.initialize()`. By default, the JCA provider will be installed in the list of
  providers maintained by the `java.security.Security` class. If you do not wish the provider
  to be installed, create a
  {ref}`mozilla_projects_nss_jss_cryptomanager_cryptomanager_initializationvalues` object, set
  its `installJSSProvider` field to `false`, and pass the `InitializationValues` object to
  `CryptoManager.initialize()`.
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### [Specifying the CryptoToken](#specifying_the_cryptotoken)

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- All cryptographic operations in JSS and NSS occur on a particular PKCS #11 token, implemented
  in software or hardware. There is no clean way to specify this token through the JCA API. By
  default, the JSS provider carries out all operations except MessageDigest on the Internal Key
  Storage Token, a software token included in JSS/NSS. MessageDigest operations take place by
  default on the Internal Crypto Token, another internal software token in JSS/NSS. There is no
  good design reason for this difference, but it is necessitated by a quirk in the NSS
  implementation.

  In order to use a different token, use `CryptoManager.setThreadToken()`. This sets the token
  to be used by the JSS JCA provider in the current thread. When you call `getInstance()` on a
  JCA class, the JSS provider checks the current per-thread default token (by calling
  `CryptoManager.getThreadToken()`) and instructs the new object to use that token for
  cryptographic operations. The per-thread default token setting is only consulted inside
  `getInstance()`. Once a JCA object has been created it will continue to use the same token,
  even if the application later changes the per-thread default token.

  Whenever a new thread is created, its token is initialized to the default, the Internal Key
  Storage Token. Thus, the thread token is not inherited from the parent thread.

  The following example shows how you can specify which token is used for various JCA
  operations:

  ```{code}
  // Lookup PKCS #11 tokens
  CryptoManager manager = CryptoManager.getInstance();
  CryptoToken tokenA = manager.getTokenByName("TokenA");
  CryptoToken tokenB = manager.getTokenByName("TokenB");

  // Create an RSA KeyPairGenerator using TokenA
  manager.setThreadToken(tokenA);
  KeyPairGenerator rsaKpg = KeyPairGenerator.getInstance("RSA", "Mozilla-JSS");

  // Create a DSA KeyPairGenerator using TokenB
  manager.setThreadToken(tokenB);
  KeyPairGenerator dsaKpg  = KeyPairGenerator.getInstance("DSA", "Mozilla-JSS");

  // Generate an RSA KeyPair. This will happen on TokenA because TokenA
  // was the per-thread default token when rsaKpg was created.
  rsaKpg.initialize(1024);
  KeyPair rsaPair = rsaKpg.generateKeyPair();

  // Generate a DSA KeyPair. This will happen on TokenB because TokenB
  // was the per-thread default token when dsaKpg was created.
  dsaKpg.initialize(1024);
  KeyPair dsaPair = dsaKpg.generateKeyPair();
  ```

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### [Supported Classes](#supported_classes)

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- [Cipher](#cipher)

- [DSAPrivateKey](#dsaprivatekey)

- DSAPublicKey

- [KeyFactory](#keyfactory)

- [KeyGenerator](#keygenerator)

- [KeyPairGenerator](#keypairgenerator)

- [Mac](#mac)

- [MessageDigest](#messagedigest)

- [RSAPrivateKey](#rsaprivatekey)

- RSAPublicKey

- [SecretKeyFactory](#secretkeyfactory)

- [SecretKey](#secretkey)

- [SecureRandom](#securerandom)

- [Signature](#signature)

  ```{rubric} What's Not Supported
  ```

  - The following classes don't work very well:

    - **KeyStore:** There are many serious problems mapping the JCA keystore interface onto
      NSS's model of PKCS #11 modules. The current implementation is almost useless. Since
      these problems lie deep in the NSS design and implementation, there is no clear
      timeframe for fixing them. Meanwhile, the `org.mozilla.jss.crypto.CryptoStore` class
      can be used for some of this functionality.
:::

```{rubric} Cipher
:name: Cipher_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- - AES
  - DES
  - DESede (*DES3* )
  - RC2
  - RC4
  - RSA
  - The following modes and padding schemes are supported:

  ```{eval-rst}
  +------------------------------+------------------------------+------------------------------+
  | Algorithm                    | Mode                         | Padding                      |
  +------------------------------+------------------------------+------------------------------+
  | DES                          | ECB                          | NoPadding                    |
  +------------------------------+------------------------------+------------------------------+
  |                              | CBC                          | NoPadding                    |
  +------------------------------+------------------------------+------------------------------+
  |                              |                              | PKCS5 Padding                |
  +------------------------------+------------------------------+------------------------------+
  | DESede                       | ECB                          | NoPadding                    |
  | *DES3*                       |                              |                              |
  +------------------------------+------------------------------+------------------------------+
  |                              | CBC                          | NoPadding                    |
  +------------------------------+------------------------------+------------------------------+
  |                              |                              | PKCS5 Padding                |
  +------------------------------+------------------------------+------------------------------+
  | AES                          | ECB                          | NoPadding                    |
  +------------------------------+------------------------------+------------------------------+
  |                              | CBC                          | NoPadding                    |
  +------------------------------+------------------------------+------------------------------+
  |                              |                              | PKCS5 Padding                |
  +------------------------------+------------------------------+------------------------------+
  | RC4                          | *None*                       | *None*                       |
  +------------------------------+------------------------------+------------------------------+
  | RC2                          | CBC                          | NoPadding                    |
  +------------------------------+------------------------------+------------------------------+
  |                              |                              | PKCS5Padding                 |
  +------------------------------+------------------------------+------------------------------+
  ```

  - The SecureRandom argument passed to `initSign()` and `initVerify()` is ignored, because
    NSS does not support specifying an external source of randomness.

```{rubric} DSAPrivateKey
:name: DSAPrivateKey_2
```

- `getX()` is not supported because NSS does not support extracting data from private keys.

```{rubric} KeyFactory
:name: KeyFactory_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- > - DSA
  > - RSA
  > - The following transformations are supported for `generatePublic()` and
  >   `generatePrivate()`:

  ```{eval-rst}
  +----------------------------------------------+----------------------------------------------+
  | From                                         | To                                           |
  +----------------------------------------------+----------------------------------------------+
  | ``RSAPublicKeySpec``                         | ``RSAPublicKey``                             |
  +----------------------------------------------+----------------------------------------------+
  | ``DSAPublicKeySpec``                         | ``DSAPublicKey``                             |
  +----------------------------------------------+----------------------------------------------+
  | ``X509EncodedKeySpec``                       | ``RSAPublicKey``                             |
  |                                              | ``DSAPublicKey``                             |
  +----------------------------------------------+----------------------------------------------+
  | ``RSAPrivateCrtKeySpec``                     | ``RSAPrivateKey``                            |
  +----------------------------------------------+----------------------------------------------+
  | ``DSAPrivateKeySpec``                        | ``DSAPrivateKey``                            |
  +----------------------------------------------+----------------------------------------------+
  | ``PKCS8EncodedKeySpec``                      | ``RSAPrivateKey``                            |
  |                                              | ``DSAPrivateKey``                            |
  +----------------------------------------------+----------------------------------------------+
  ```

  > - `getKeySpec()` is not supported. This method exports key material in plaintext and is
  >   therefore insecure. Note that a public key's data can be accessed directly from the key.
  > - `translateKey()` simply gets the encoded form of the given key and then tries to import
  >   it by calling `generatePublic()` or `generatePrivate()`. Only `X509EncodedKeySpec` is
  >   supported for public keys, and only `PKCS8EncodedKeySpec` is supported for private keys.

```{rubric} KeyGenerator
:name: KeyGenerator_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- - AES
  - DES
  - DESede (*DES3* )
  - RC4
  - The SecureRandom argument passed to `init()` is ignored, because NSS does not support
    specifying an external source of randomness.
  - None of the key generation algorithms accepts an `AlgorithmParameterSpec`.

```{rubric} KeyPairGenerator
:name: KeyPairGenerator_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- - DSA
  - RSA
  - The SecureRandom argument passed to initialize() is ignored, because NSS does not support
    specifying an external source of randomness.

```{rubric} Mac
:name: Mac_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- - HmacSHA1 (*Hmac-SHA1* )
  - Any secret key type (AES, DES, etc.) can be used as the MAC key, but it must be a JSS key.
    That is, it must be an `instanceof org.mozilla.jss.crypto.SecretKeyFacade`.
  - The params passed to `init()` are ignored.

```{rubric} MessageDigest
:name: MessageDigest_2
```

```{rubric} Supported Algorithms
```

- - MD5
  - MD2
  - SHA-1 (*SHA1, SHA* )

```{rubric} RSAPrivateKey
:name: RSAPrivateKey_2
```

```{rubric} Notes
```

- - `getModulus()` is not supported because NSS does not support extracting data from private
    keys.
  - `getPrivateExponent()` is not supported because NSS does not support extracting data from
    private keys.

```{rubric} SecretKeyFactory
:name: SecretKeyFactory_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- > - AES
  > - DES
  > - DESede (*DES3* )
  > - PBAHmacSHA1
  > - PBEWithMD5AndDES
  > - PBEWithSHA1AndDES
  > - PBEWithSHA1AndDESede (*PBEWithSHA1AndDES3* )
  > - PBEWithSHA1And128RC4
  > - RC4
  > - `generateSecret` supports the following transformations:

  ```{eval-rst}
  +----------------------------------------------+----------------------------------------------+
  | KeySpec Class                                | Key Algorithm                                |
  +----------------------------------------------+----------------------------------------------+
  | PBEKeySpec                                   | *Using the appropriate PBE algorithm:*       |
  | org.mozilla.jss.crypto.PBEKeyGenParams       | DES                                          |
  |                                              | DESede                                       |
  |                                              | RC4                                          |
  +----------------------------------------------+----------------------------------------------+
  | DESedeKeySpec                                | DESede                                       |
  +----------------------------------------------+----------------------------------------------+
  | DESKeySpec                                   | DES                                          |
  +----------------------------------------------+----------------------------------------------+
  | SecretKeySpec                                | AES                                          |
  |                                              | DES                                          |
  |                                              | DESede                                       |
  |                                              | RC4                                          |
  +----------------------------------------------+----------------------------------------------+
  ```

  > - `getKeySpec` supports the following transformations:

  ```{eval-rst}
  +----------------------------------------------+----------------------------------------------+
  | Key Algorithm                                | KeySpec Class                                |
  +----------------------------------------------+----------------------------------------------+
  | DESede                                       | DESedeKeySpec                                |
  +----------------------------------------------+----------------------------------------------+
  | DES                                          | DESKeySpec                                   |
  +----------------------------------------------+----------------------------------------------+
  | DESede                                       | SecretKeySpec                                |
  | DES                                          |                                              |
  | AES                                          |                                              |
  | RC4                                          |                                              |
  +----------------------------------------------+----------------------------------------------+
  ```

  > - For increased security, some SecretKeys may not be extractable from their PKCS #11 token.
  >   In this case, the key should be wrapped (encrypted with another key), and then the
  >   encrypted key might be extractable from the token. This policy varies across PKCS #11
  >   tokens.
  > - `translateKey` tries two approaches to copying keys. First, it tries to copy the key
  >   material directly using NSS calls to PKCS #11. If that fails, it calls `getEncoded()` on
  >   the source key, and then tries to create a new key on the target token from the encoded
  >   bits. Both of these operations will fail if the source key is not extractable.
  > - The class `java.security.spec.PBEKeySpec` in JDK versions earlier than 1.4 does not
  >   contain the salt and iteration fields, which are necessary for PBE key generation. These
  >   fields were added in JDK 1.4. If you are using a JDK (or JRE) version earlier than 1.4, you
  >   cannot use class `java.security.spec.PBEKeySpec`. Instead, you can use
  >   `org.mozilla.jss.crypto.PBEKeyGenParams`. If you are using JDK (or JRE) 1.4 or later, you
  >   can use `java.security.spec.PBEKeySpec` or `org.mozilla.jss.crypto.PBEKeyGenParams`.

```{rubric} SecretKey
:name: SecretKey_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- - AES
  - DES
  - DESede (*DES3* )
  - HmacSHA1
  - RC2
  - RC4
  - `SecretKey` is implemented by the class `org.mozilla.jss.crypto.SecretKeyFacade`, which
    acts as a wrapper around the JSS class `SymmetricKey`. Any `SecretKeys` handled by JSS
    will actually be `SecretKeyFacades`. This should usually be transparent.

```{rubric} SecureRandom
:name: SecureRandom_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- - pkcs11prng
  - This invokes the NSS internal pseudorandom number generator.

```{rubric} Signature
:name: Signature_2
```

```{rubric} Supported Algorithms
```

```{rubric} Notes
```

- - SHA1withDSA (*DSA, DSS, SHA/DSA, SHA-1/DSA, SHA1/DSA, DSAWithSHA1, SHAwithDSA* )
  - SHA-1/RSA (*SHA1/RSA, SHA1withRSA* )
  - MD5/RSA (*MD5withRSA* )
  - MD2/RSA
  - The `SecureRandom` argument passed to `initSign()` and `initVerify()` is ignored,
    because NSS does not support specifying an external source of randomness.
