validate that ec curve matches algo

lib/ssh_data/public_key/dsa.rb

@@ -51,7 +51,7 @@ module SSHData
 
       def initialize(algo:, p:, q:, g:, y:)
         unless algo == ALGO_DSA
-          raise DecodeError, "bad algorithm: #{algo.inpsect}"
+          raise DecodeError, "bad algorithm: #{algo.inspect}"
         end
 
         @algo = algo

lib/ssh_data/public_key/ecdsa.rb

@@ -57,7 +57,11 @@ module SSHData
 
       def initialize(algo:, curve:, public_key:)
         unless [ALGO_ECDSA256, ALGO_ECDSA384, ALGO_ECDSA521].include?(algo)
-          raise DecodeError, "bad algorithm: #{algo.inpsect}"
+          raise DecodeError, "bad algorithm: #{algo.inspect}"
+        end
+
+        unless algo == "ecdsa-sha2-#{curve}"
+          raise DecodeError, "bad curve: #{curve.inspect}"
         end
 
         @algo = algo

lib/ssh_data/public_key/ed25519.rb

@@ -11,7 +11,7 @@ module SSHData
 
       def initialize(algo:, pk:)
         unless algo == ALGO_ED25519
-          raise DecodeError, "bad algorithm: #{algo.inpsect}"
+          raise DecodeError, "bad algorithm: #{algo.inspect}"
         end
 
         @algo = algo

lib/ssh_data/public_key/rsa.rb

@@ -5,7 +5,7 @@ module SSHData
 
       def initialize(algo:, e:, n:)
         unless algo == ALGO_RSA
-          raise DecodeError, "bad algorithm: #{algo.inpsect}"
+          raise DecodeError, "bad algorithm: #{algo.inspect}"
         end
 
         @algo = algo

spec/public_key/ecdsa_spec.rb

@@ -77,4 +77,17 @@ describe SSHData::PublicKey::ECDSA do
     }.not_to raise_error
 
   end
+
+  it "blows up if the curve doesn't match the key type" do
+    # outer layer claims to be p384, but curve and public key are p256
+    malformed = [SSHData::PublicKey::ALGO_ECDSA384, Base64.strict_encode64([
+      SSHData::Encoding.encode_string(SSHData::PublicKey::ALGO_ECDSA384),
+      SSHData::Encoding.encode_string(openssh_key.curve),
+      SSHData::Encoding.encode_string(openssh_key.public_key),
+    ].join)].join(" ")
+
+    expect {
+      SSHData::PublicKey.parse(malformed)
+    }.to raise_error(SSHData::DecodeError)
+  end
 end