Post work for #2637

Improve test cases, config settings, also show SSH config settings on admin config panel.

conf/app.ini

@@ -71,13 +71,13 @@ SSH_PORT = 22
 SSH_LISTEN_PORT = %(SSH_PORT)s
 ; Root path of SSH directory, default is '~/.ssh', but you have to use '/home/git/.ssh'.
 SSH_ROOT_PATH = 
-; override engine choice to check public keys (default: 'ssh-keygen' when
-; DISABLE_SSH is set to false else 'native')
-SSH_PUBLICKEY_CHECK =
-; directory to create temporary files when using ssh-keygen (default: /tmp)
-SSH_WORK_PATH =
-; path to ssh-keygen (default: result of `which ssh-keygen`)
-SSH_KEYGEN_PATH =
+; Directory to create temporary files when test publick key using ssh-keygen,
+; default is system temporary directory.
+SSH_KEY_TEST_PATH =
+; Path to ssh-keygen, default is 'ssh-keygen' and let shells find out which one to call.
+SSH_KEYGEN_PATH = ssh-keygen
+; Indicate whether to check minimum key size with corresponding type
+MINIMUM_KEY_SIZE_CHECK = false
 ; Disable CDN even in "prod" mode
 OFFLINE_MODE = false
 DISABLE_ROUTER_LOG = false
@@ -98,6 +98,13 @@ ENABLE_GZIP = false
 ; Landing page for non-logged users, can be "home" or "explore"
 LANDING_PAGE = home
 
+; Define allowed algorithms and their minimum key length (use -1 to disable a type)
+[ssh.minimum_key_sizes]
+ED25519 = 256
+ECDSA   = 256
+RSA     = 2048
+DSA     = 1024
+
 [database]
 ; Either "mysql", "postgres" or "sqlite3", it's your choice
 DB_TYPE = mysql
@@ -139,15 +146,6 @@ ENABLE_REVERSE_PROXY_AUTHENTICATION = false
 ENABLE_REVERSE_PROXY_AUTO_REGISTRATION = false
 ; Enable captcha validation for registration
 ENABLE_CAPTCHA = true
-; Do not check minimum key size with corresponding type
-ENABLE_MINIMUM_KEY_SIZE_CHECK = false
-
-; define allowed algorithms and their minimum key length (use -1 to disable a type)
-[service.minimum_key_sizes]
-ED25519 = 256
-ECDSA   = 256
-RSA     = 2048
-DSA     = 1024
 
 [webhook]
 ; Hook task queue length