我在composer.json中引入了

"require": {
    "php": ">=5.5.9",
    "laravel/framework": "5.2.*",
    "dingo/api": "1.0.*@dev",
    "tymon/jwt-auth": "0.5.*"},

当执行composer update是

出现以下的问题

Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - tymon/jwt-auth 0.5.4 requires namshi/jose 5.0.* -> satisfiable by namshi/jose[5.0.0, 5.0.1, 5.0.2].
    - tymon/jwt-auth 0.5.5 requires namshi/jose 5.0.* -> satisfiable by namshi/jose[5.0.0, 5.0.1, 5.0.2].
    - tymon/jwt-auth 0.5.6 requires namshi/jose 5.0.* -> satisfiable by namshi/jose[5.0.0, 5.0.1, 5.0.2].
    - tymon/jwt-auth 0.5.7 requires namshi/jose 5.0.* -> satisfiable by namshi/jose[5.0.0, 5.0.1, 5.0.2].
    - tymon/jwt-auth 0.5.8 requires namshi/jose 5.0.* -> satisfiable by namshi/jose[5.0.0, 5.0.1, 5.0.2].
    - tymon/jwt-auth 0.5.9 requires namshi/jose 5.0.* -> satisfiable by namshi/jose[5.0.0, 5.0.1, 5.0.2].
    - tymon/jwt-auth 0.5.1 requires namshi/jose 2.2.* -> satisfiable by namshi/jose[2.2.0, 2.2.1, 2.2.2].
    - tymon/jwt-auth 0.5.2 requires namshi/jose 2.2.* -> satisfiable by namshi/jose[2.2.0, 2.2.1, 2.2.2].
    - tymon/jwt-auth 0.5.3 requires namshi/jose 2.2.* -> satisfiable by namshi/jose[2.2.0, 2.2.1, 2.2.2].
    - tymon/jwt-auth 0.5.0 requires namshi/jose 2.0.* -> satisfiable by namshi/jose[2.0.0, 2.0.1, 2.0.2, 2.0.3].
    - namshi/jose 5.0.2 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 5.0.1 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 5.0.0 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 2.2.2 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 2.2.1 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 2.2.0 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 2.0.3 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 2.0.2 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 2.0.1 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - namshi/jose 2.0.0 requires lib-openssl * -> the requested linked library openssl has the wrong version installed or is missing from your system, make sure to have the extension providing it.
    - Installation request for tymon/jwt-auth 0.5.* -> satisfiable by tymon/jwt-auth[0.5.0, 0.5.1, 0.5.2, 0.5.3, 0.5.4, 0.5.5, 0.5.6, 0.5.7, 0.5.8, 0.5.9].

请问怎么回事哦···