Ssh: add Match keyword support (#695)

Signed-off-by: Guillaume Ranquet <[email protected]>

lenses/ssh.aug

@@ -92,7 +92,7 @@ module Ssh =
                         | rekey_limit
 
     let key_re = /[A-Za-z0-9]+/
-               - /SendEnv|Host|ProxyCommand|RemoteForward|LocalForward|MACs|Ciphers|(HostKey|Kex)Algorithms|PubkeyAcceptedKeyTypes|GlobalKnownHostsFile|RekeyLimit/i
+               - /SendEnv|Host|Match|ProxyCommand|RemoteForward|LocalForward|MACs|Ciphers|(HostKey|Kex)Algorithms|PubkeyAcceptedKeyTypes|GlobalKnownHostsFile|RekeyLimit/i
 
 
     let other_entry = [ indent . key key_re
@@ -105,11 +105,26 @@ module Ssh =
     let host = [ key /Host/i . spc . value_to_eol . eol . entry* ]
 
 
+   let condition_entry =
+    let value = store  /[^ \t\r\n=]+/ in
+    [ spc . key /[A-Za-z0-9]+/ . spc . value ]
+
+   let match_cond =
+     [ label "Condition" . condition_entry+ . eol ]
+
+   let match_entry = entry
+
+   let match =
+     [ key /Match/i . match_cond
+        . [ label "Settings" .  match_entry+ ]
+     ]
+
+
 (************************************************************************
  * Group:                 LENS
  *************************************************************************)
 
-    let lns = entry* . host*
+    let lns = entry* . (host | match)*
 
     let xfm = transform lns (incl "/etc/ssh/ssh_config" .
                              incl (Sys.getenv("HOME") . "/.ssh/config") .

lenses/tests/test_ssh.aug

@@ -5,6 +5,9 @@ module Test_ssh =
 "# start
 IdentityFile /etc/ssh/identity.asc
 
+Match final all
+   GSSAPIAuthentication yes
+
 Host suse.cz
    ForwardAgent yes
 SendEnv LC_LANG
@@ -30,6 +33,15 @@ PubkeyAcceptedKeyTypes [email protected],ssh-ed25519,ssh-rsa-cert
     { "#comment" = "start" }
     { "IdentityFile" = "/etc/ssh/identity.asc" }
     { }
+    { "Match"
+      { "Condition"
+        { "final" = "all" }
+      }
+      { "Settings"
+        { "GSSAPIAuthentication" = "yes" }
+        {  }
+      }
+    }
     { "Host"	= "suse.cz"
 	{ "ForwardAgent"  = "yes" }
 	{ "SendEnv"