(PECL ssh2 >= 0.10)
ssh2_publickey_add — Add an authorized publickey
Note: 公钥系统用于管理服务器上的客户已经被认证的公钥。要用公钥认证方法在远程系统上认证，应该用 ssh2_auth_pubkey_file() 函数。
Publickey Subsystem resource created by ssh2_publickey_init().
Publickey algorithm (e.g.): ssh-dss, ssh-rsa
Publickey blob as raw binary data
If the specified key already exists, should it be overwritten?
Associative array of attributes to assign to this public key. Refer to ietf-secsh-publickey-subsystem for a list of supported attributes. To mark an attribute as mandatory, precede its name with an asterisk. If the server is unable to support an attribute marked mandatory, it will abort the add process.
如果成功则返回 TRUE，失败则返回 FALSE。
Example #1 Adding a publickey with ssh2_publickey_add()
<?php
$ssh2 = ssh2_connect('shell.example.com', 22);
ssh2_auth_password($ssh2, 'jdoe', 'password');
$pkey = ssh2_publickey_init($ssh2);
$keyblob = base64_decode('
AAAAB3NzaC1yc2EAAAABIwAAAIEA5HVt6VqSGd5PTrLRdjNONxXH1tVFGn0
Bd26BF0aCP9qyJRlvdJ3j4WBeX4ZmrveGrjMgkseSYc4xZ26sDHwfL351xj
zaLpipu\BGRrw17mWVBhuCExo476ri5tQFzbTc54VEHYckxQ16CjSTibI5X
69GmnYC9PNqEYq/1TP+HF10=');
ssh2_publickey_add($ssh2, 'ssh-rsa', $keyblob, false, array('comment'=>"John's Key"));
?>