SSL tests
=========

SSL testcases are configured in the `ssl-tests` directory.

Each `ssl_*.cnf.in` file contains a number of test configurations. These files
are used to generate testcases in the OpenSSL CONF format.

The precise test output can be dependent on the library configuration. The test
harness generates the output files on the fly.

However, for verification, we also include checked-in configuration outputs
corresponding to the default configuration. These testcases live in
`test/ssl-tests/*.cnf` files.

For more details, see `ssl-tests/01-simple.cnf.in` for an example.

Configuring the test
--------------------

First, give your test a name. The names do not have to be unique.

An example test input looks like this:

    {
        name => "test-default",
        server => { "CipherString" => "DEFAULT" },
        client => { "CipherString" => "DEFAULT" },
        test   => { "ExpectedResult" => "Success" },
    }

The test section supports the following options

### Test mode

* Method - the method to test. One of DTLS or TLS.

* HandshakeMode - which handshake flavour to test:
  - Simple - plain handshake (default)
  - Resume - test resumption
  - RenegotiateServer - test server initiated renegotiation
  - RenegotiateClient - test client initiated renegotiation

When HandshakeMode is Resume or Renegotiate, the original handshake is expected
to succeed. All configured test expectations are verified against the second
handshake.

* ApplicationData - amount of application data bytes to send (integer, defaults
  to 256 bytes). Applies to both client and server. Application data is sent in
  64kB chunks (but limited by MaxFragmentSize and available parallelization, see
  below).

* MaxFragmentSize - maximum send fragment size (integer, defaults to 512 in
  tests - see `SSL_CTX_set_max_send_fragment` for documentation). Applies to
  both client and server. Lowering the fragment size will split handshake and
  application data up between more `SSL_write` calls, thus allowing to exercise
  different code paths. In particular, if the buffer size (64kB) is at least
  four times as large as the maximum fragment, interleaved multi-buffer crypto
  implementations may be used on some platforms.

### Test expectations

* ExpectedResult - expected handshake outcome. One of
  - Success - handshake success
  - ServerFail - serverside handshake failure
  - ClientFail - clientside handshake failure
  - InternalError - some other error

* ExpectedClientAlert, ExpectedServerAlert - expected alert. See
  `test/helpers/ssl_test_ctx.c` for known values. Note: the expected alert is currently
  matched against the _last_ received alert (i.e., a fatal alert or a
  `close_notify`). Warning alert expectations are not yet supported. (A warning
  alert will not be correctly matched, if followed by a `close_notify` or
  another alert.)

* ExpectedProtocol - expected negotiated protocol. One of
  SSLv3, TLSv1, TLSv1.1, TLSv1.2.

* SessionTicketExpected - whether or not a session ticket is expected
  - Ignore - do not check for a session ticket (default)
  - Yes - a session ticket is expected
  - No - a session ticket is not expected

* SessionIdExpected - whether or not a session id is expected
  - Ignore - do not check for a session id (default)
  - Yes - a session id is expected
  - No - a session id is not expected

* ResumptionExpected - whether or not resumption is expected (Resume mode only)
  - Yes - resumed handshake
  - No - full handshake (default)

* ExpectedNPNProtocol, ExpectedALPNProtocol - NPN and ALPN expectations.

* ExpectedTmpKeyType - the expected algorithm or curve of server temp key

* ExpectedServerCertType, ExpectedClientCertType - the expected algorithm or
  curve of server or client certificate

* ExpectedServerSignHash, ExpectedClientSignHash - the expected
  signing hash used by server or client certificate

* ExpectedServerSignType, ExpectedClientSignType - the expected
  signature type used by server or client when signing messages

* ExpectedClientCANames - for client auth list of CA names the server must
  send. If this is "empty" the list is expected to be empty otherwise it
  is a file of certificates whose subject names form the list.

* ExpectedServerCANames - list of CA names the client must send, TLS 1.3 only.
  If this is "empty" the list is expected to be empty otherwise it is a file
  of certificates whose subject names form the list.

Configuring the client and server
---------------------------------

The client and server configurations can be any valid `SSL_CTX`
configurations. For details, see the manpages for `SSL_CONF_cmd`.

Give your configurations as a dictionary of CONF commands, e.g.

    server => {
        "CipherString" => "DEFAULT",
        "MinProtocol" => "TLSv1",
    }

The following sections may optionally be defined:

* server2 - this section configures a secondary context that is selected via the
  ServerName test option. This context is used whenever a ServerNameCallback is
  specified. If the server2 section is not present, then the configuration
  matches server.
* resume_server - this section configures the client to resume its session
  against a different server. This context is used whenever HandshakeMode is
  Resume. If the resume_server section is not present, then the configuration
  matches server.
* resume_client - this section configures the client to resume its session with
  a different configuration. In practice this may occur when, for example,
  upgraded clients reuse sessions persisted on disk.  This context is used
  whenever HandshakeMode is Resume. If the resume_client section is not present,
  then the configuration matches client.

### Configuring callbacks and additional options

Additional handshake settings can be configured in the `extra` section of each
client and server:

    client => {
        "CipherString" => "DEFAULT",
        extra => {
            "ServerName" => "server2",
        }
    }

#### Supported client-side options

* ClientVerifyCallback - the client's custom certificate verify callback.
  Used to test callback behaviour. One of
  - None - no custom callback (default)
  - AcceptAll - accepts all certificates.
  - RejectAll - rejects all certificates.

* ServerName - the server the client should attempt to connect to. One of
  - None - do not use SNI (default)
  - server1 - the initial context
  - server2 - the secondary context
  - invalid - an unknown context

* CTValidation - Certificate Transparency validation strategy. One of
  - None - no validation (default)
  - Permissive - SSL_CT_VALIDATION_PERMISSIVE
  - Strict - SSL_CT_VALIDATION_STRICT

#### Supported server-side options

* ServerNameCallback - the SNI switching callback to use
  - None - no callback (default)
  - IgnoreMismatch - continue the handshake on SNI mismatch
  - RejectMismatch - abort the handshake on SNI mismatch

* BrokenSessionTicket - a special test case where the session ticket callback
  does not initialize crypto.
  - No (default)
  - Yes

#### Mutually supported options

* NPNProtocols, ALPNProtocols - NPN and ALPN settings. Server and client
  protocols can be specified as a comma-separated list, and a callback with the
  recommended behaviour will be installed automatically.

* SRPUser, SRPPassword - SRP settings. For client, this is the SRP user to
  connect as; for server, this is a known SRP user.

### Default server and client configurations

The default server certificate and CA files are added to the configurations
automatically. Server certificate verification is requested by default.

You can override these options by redefining them:

    client => {
        "VerifyCAFile" => "/path/to/custom/file"
    }

or by deleting them

    client => {
        "VerifyCAFile" => undef
    }

Adding a test to the test harness
---------------------------------

1. Add a new test configuration to `test/ssl-tests`, following the examples of
   existing `*.cnf.in` files (for example, `01-simple.cnf.in`).

2. Generate the generated `*.cnf` test input file. You can do so by running
   `generate_ssl_tests.pl`:

    $ ./config
    $ cd test
    $ TOP=.. perl -I ../util/perl/ generate_ssl_tests.pl \
      ssl-tests/my.cnf.in default > ssl-tests/my.cnf

where `my.cnf.in` is your test input file and `default` is the provider to use.
For all the pre-generated test files you should use the default provider.

For example, to generate the test cases in `ssl-tests/01-simple.cnf.in`, do

    $ TOP=.. perl -I ../util/perl/ generate_ssl_tests.pl \
      ssl-tests/01-simple.cnf.in default > ssl-tests/01-simple.cnf

Alternatively (hackish but simple), you can comment out

    unlink glob $tmp_file;

in `test/recipes/80-test_ssl_new.t` and run

    $ make TESTS=test_ssl_new test

This will save the generated output in a `*.tmp` file in the build directory.

3. Update the number of tests planned in `test/recipes/80-test_ssl_new.t`. If
   the test suite has any skip conditions, update those too (see
   `test/recipes/80-test_ssl_new.t` for details).

Running the tests with the test harness
---------------------------------------

    HARNESS_VERBOSE=yes make TESTS=test_ssl_new test

Running a test manually
-----------------------

These steps are only needed during development. End users should run `make test`
or follow the instructions above to run the SSL test suite.

To run an SSL test manually from the command line, the `TEST_CERTS_DIR`
environment variable to point to the location of the certs. E.g., from the root
OpenSSL directory, do

    $ CTLOG_FILE=test/ct/log_list.cnf TEST_CERTS_DIR=test/certs test/ssl_test \
      test/ssl-tests/01-simple.cnf default

or for shared builds

    $ CTLOG_FILE=test/ct/log_list.cnf  TEST_CERTS_DIR=test/certs \
      util/wrap.pl test/ssl_test test/ssl-tests/01-simple.cnf default

In the above examples, `default` is the provider to use.

Note that the test expectations sometimes depend on the Configure settings. For
example, the negotiated protocol depends on the set of available (enabled)
protocols: a build with `enable-ssl3` has different test expectations than a
build with `no-ssl3`.

The Perl test harness automatically generates expected outputs, so users who
just run `make test` do not need any extra steps.

However, when running a test manually, keep in mind that the repository version
of the generated `test/ssl-tests/*.cnf` correspond to expected outputs in with
the default Configure options. To run `ssl_test` manually from the command line
in a build with a different configuration, you may need to generate the right
`*.cnf` file from the `*.cnf.in` input first.