== Test Signature
    $ yubico-piv-tool -a read-certificate -s <slot> [ -o cert.pem ]
    $ yubico-piv-tool -a verify-pin -a test-signature -s <slot> [ -i cert.pem ]

=== Description
Tests signing functions.

"test-signature" and "test-decipher" are actions that require verifying the PIN code,
which has to be done in an action that must take place before the generation action,
otherwise the tests will fail.

Performing the test will require the certificate stored on the slot to test. This is
done using the "read-certificate" action first.

=== Parameters

|===================================
|Parameter         | Required | Optional | Description | Possible values | Default value

|-s, --slot        | X | | What key slot to operate on | 9a, 9c, 9d, 9e, 82, 83, 84, 85, 86, 87, 88, 89,
                                                          8a, 8b, 8c, 8d, 8e, 8f, 90, 91, 92, 93, 94, 95, f9 |
|-i, --input       | | X | Filename to use as input | file name or "-" for stdin | -
|-o, --output      | | X | Filename to use as output | file name or "-" for stdin | -
|===================================

=== Examples

    $ yubico-piv-tool -a read-certificate -s 9a
    -----BEGIN CERTIFICATE-----
    MIIBuTCCAWCgAwIBAgIJAMOZXtijzEepMAoGCCqGSM49BAMCMDgxETAPBgNVBAMM
    CHBpdl9hdXRoMQ0wCwYDVQQLDAR0ZXN0MRQwEgYDVQQKDAtleGFtcGxlLmNvbTAe
    Fw0xOTA4MTMwODEwNDVaFw0yMDA4MTIwODEwNDVaMDgxETAPBgNVBAMMCHBpdl9h
    dXRoMQ0wCwYDVQQLDAR0ZXN0MRQwEgYDVQQKDAtleGFtcGxlLmNvbTBZMBMGByqG
    SM49AgEGCCqGSM49AwEHA0IABKPfSKeNY204JiHsSUwDAV8GuYqZOHfJJxrT4E0q
    VWsKdC5zwRc7xvb2YgbMonPW5BfIUi766/VwWN54UsqWVuWjUzBRMB0GA1UdDgQW
    BBR/bpCmGr+ark0VbGX5UvYWy9dM9DAfBgNVHSMEGDAWgBR/bpCmGr+ark0VbGX5
    UvYWy9dM9DAPBgNVHRMBAf8EBTADAQH/MAoGCCqGSM49BAMCA0cAMEQCIHZZe7Xm
    s6y8LKEBqGnbr1cbniHgMrvM1ST6GpL27HuaAiB+UwjI21GxIsd5r2avmwvT5LeZ
    gQBns9KNCIgkwx+/Iw==
    -----END CERTIFICATE-----

    $ yubico-piv-tool -a verify-pin -a test-signature -s 9a
    Enter PIN:
    Successfully verified PIN.
    Please paste the certificate to verify against...
    -----BEGIN CERTIFICATE-----
    MIIBuTCCAWCgAwIBAgIJAMOZXtijzEepMAoGCCqGSM49BAMCMDgxETAPBgNVBAMM
    CHBpdl9hdXRoMQ0wCwYDVQQLDAR0ZXN0MRQwEgYDVQQKDAtleGFtcGxlLmNvbTAe
    Fw0xOTA4MTMwODEwNDVaFw0yMDA4MTIwODEwNDVaMDgxETAPBgNVBAMMCHBpdl9h
    dXRoMQ0wCwYDVQQLDAR0ZXN0MRQwEgYDVQQKDAtleGFtcGxlLmNvbTBZMBMGByqG
    SM49AgEGCCqGSM49AwEHA0IABKPfSKeNY204JiHsSUwDAV8GuYqZOHfJJxrT4E0q
    VWsKdC5zwRc7xvb2YgbMonPW5BfIUi766/VwWN54UsqWVuWjUzBRMB0GA1UdDgQW
    BBR/bpCmGr+ark0VbGX5UvYWy9dM9DAfBgNVHSMEGDAWgBR/bpCmGr+ark0VbGX5
    UvYWy9dM9DAPBgNVHRMBAf8EBTADAQH/MAoGCCqGSM49BAMCA0cAMEQCIHZZe7Xm
    s6y8LKEBqGnbr1cbniHgMrvM1ST6GpL27HuaAiB+UwjI21GxIsd5r2avmwvT5LeZ
    gQBns9KNCIgkwx+/Iw==
    -----END CERTIFICATE-----
    Successful ECDSA verification.

It is also possible to combine the commands above into one single command (notice the order of the actions):

    $ yubico-piv-tool -a read-certificate -a verify-pin -a test-signature -s 9a -o cert.pem -i cert.pem
    Enter PIN:
    Successfully verified PIN.
    Successful ECDSA verification.
