feat: add support for additional host key types

also fixes up support for crystal 0.36.0

shard.yml

@@ -1,5 +1,5 @@
 name: ssh2
-version: 1.4.2
+version: 1.5.0
 
 development_dependencies:
   ameba:

spec/ssh2_spec.cr

@@ -70,13 +70,25 @@ describe SSH2::KnownHosts do
       known_hosts = session.knownhosts
       key, key_type = session.hostkey
       typemask = LibSSH2::TypeMask::PLAIN
+
+      # NOTE:: technically the type mask can be generated programatically
+      # by shifting the key_type integer value by 18
+      # https://github.com/libssh2/libssh2/blob/6c7769dcc422250d14af1b06fce378b6ee009440/include/libssh2.h#L996
       case key_type
       when LibSSH2::HostKeyType::RSA
         typemask |= LibSSH2::TypeMask::KEY_SSHRSA
       when LibSSH2::HostKeyType::DSS
         typemask |= LibSSH2::TypeMask::KEY_SSHDSS
+      when LibSSH2::HostKeyType::ECDSA_256
+        typemask |= LibSSH2::TypeMask::KEY_ECDSA_256
+      when LibSSH2::HostKeyType::ECDSA_384
+        typemask |= LibSSH2::TypeMask::KEY_ECDSA_384
+      when LibSSH2::HostKeyType::ECDSA_521
+        typemask |= LibSSH2::TypeMask::KEY_ECDSA_521
+      when LibSSH2::HostKeyType::ED25519
+        typemask |= LibSSH2::TypeMask::KEY_ED25519
       else
-        fail "unknown key_type"
+        fail "unknown key_type: #{key_type}"
       end
       known_hosts.add("localhost", "", key, "comment", typemask)
       known_hosts.add("127.0.0.1", "", key, "comment", typemask)

src/lib_ssh2.cr

@@ -42,10 +42,15 @@ lib LibSSH2
     LANG_SC  = 9
   end
 
+  # https://github.com/libssh2/libssh2/blob/6c7769dcc422250d14af1b06fce378b6ee009440/include/libssh2.h#L423
   enum HostKeyType
-    UNKNOWN = 0
-    RSA     = 1
-    DSS     = 2
+    UNKNOWN   = 0
+    RSA       = 1
+    DSS       = 2
+    ECDSA_256 = 3
+    ECDSA_384 = 4
+    ECDSA_521 = 5
+    ED25519   = 6
   end
 
   enum DisconnectReason
@@ -191,6 +196,7 @@ Void*) -> Void
 
   alias KnownHosts = Void*
 
+  # https://github.com/libssh2/libssh2/blob/6c7769dcc422250d14af1b06fce378b6ee009440/include/libssh2.h#L994
   @[Flags]
   enum TypeMask
     PLAIN  = 1
@@ -200,10 +206,16 @@ Void*) -> Void
     KEYENC_RAW    = (1 << 16)
     KEYENC_BASE64 = (2 << 16)
 
-    KEY_RSA1    = (1 << 18)
-    KEY_SSHRSA  = (2 << 18)
-    KEY_SSHDSS  = (3 << 18)
-    KEY_UNKNOWN = (7 << 18)
+    KEY_RSA1   = (1 << 18)
+    KEY_SSHRSA = (2 << 18)
+    KEY_SSHDSS = (3 << 18)
+
+    KEY_ECDSA_256 = (4 << 18)
+    KEY_ECDSA_384 = (5 << 18)
+    KEY_ECDSA_521 = (6 << 18)
+    KEY_ED25519   = (7 << 18)
+
+    KEY_UNKNOWN = (15 << 18)
   end
 
   enum KnownHostCheck

src/session.cr

@@ -16,6 +16,8 @@ class SSH2::Session
     handshake
   end
 
+  @handle : Pointer(Void) = Pointer(Void).new(0)
+
   def self.connect(host, port = 22)
     socket = TCPSocket.new(host, port)
     new(socket)
@@ -92,8 +94,8 @@ class SSH2::Session
   INTERACTIVE_CB = Proc(UInt8*, Int32, UInt8*, Int32, Int32, Void*, LibSSH2::Password*, Void*, Void).new do |name, name_len, instruction, instruction_len, num_prompts, _prompts, responses, data|
     # This is the number of response structures we can fill
     if num_prompts > 0
-      uname = String.new(name, name_len)
-      welcome = String.new(instruction, instruction_len)
+      uname = name.null? ? "" : String.new(name, name_len)
+      welcome = instruction.null? ? "" : String.new(instruction, instruction_len)
 
       # Obtain the details of the object that made the request (passed in the initializer)
       object_id = Pointer(Pointer(Void)).new(data.address)[0].address