Add lease-bound Remote key IPC and SDK validation

internal/tentaclewire/remote_key.go

@@ -0,0 +1,91 @@
+// Copyright (c) 2026 Storm Dragon
+// Authors: Storm Dragon, Angus Kola
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package tentaclewire
+
+import (
+	"encoding/json"
+	"strconv"
+)
+
+const RemoteKeyQueueSize = 256
+const RemoteKeyQueueBytes = 256 * 1024
+
+// RemoteKey identifies one logical, unshifted key, never an X keycode, Windows
+// VK, scan code, text to type or command to execute. Native ownership and
+// destination-layout resolution belong to a reader input owner.
+type RemoteKey struct {
+	Name    string `json:"name"`
+	Pressed bool   `json:"pressed"`
+}
+
+type RemoteKeyRequest struct {
+	RemoteOperation
+	Key RemoteKey `json:"key"`
+}
+
+func ValidRemoteKey(key RemoteKey) bool {
+	name := key.Name
+	if len(name) == 1 && (name[0] >= 'a' && name[0] <= 'z' || name[0] >= '0' && name[0] <= '9') {
+		return true
+	}
+	if len(name) >= 2 && len(name) <= 3 && name[0] == 'F' {
+		number, err := strconv.Atoi(name[1:])
+		return err == nil && number >= 1 && number <= 24 && strconv.Itoa(number) == name[1:]
+	}
+	if len(name) == 4 && name[:3] == "KP_" && name[3] >= '0' && name[3] <= '9' {
+		return true
+	}
+	switch name {
+	case "BackSpace", "Tab", "Return", "Escape", "space", "Pause", "Print", "Menu",
+		"Caps_Lock", "Num_Lock", "Scroll_Lock", "Shift_L", "Shift_R", "Control_L", "Control_R",
+		"Alt_L", "Alt_R", "Super_L", "Super_R", "Page_Up", "Page_Down", "End", "Home",
+		"Left", "Up", "Right", "Down", "Insert", "Delete",
+		"KP_Begin", "KP_Enter", "KP_Page_Up", "KP_Page_Down", "KP_End", "KP_Home",
+		"KP_Left", "KP_Up", "KP_Right", "KP_Down", "KP_Insert", "KP_Delete",
+		"KP_Multiply", "KP_Add", "KP_Separator", "KP_Subtract", "KP_Decimal", "KP_Divide",
+		"semicolon", "equal", "comma", "minus", "period", "slash", "grave", "bracketleft",
+		"backslash", "bracketright", "apostrophe":
+		return true
+	}
+	return false
+}
+
+func ValidRemoteKeyRequest(request RemoteKeyRequest) bool {
+	return len(request.Lease) == 32 && request.Epoch != 0 && request.Sequence != 0 && ValidRemoteKey(request.Key)
+}
+
+func (key *RemoteKey) UnmarshalJSON(data []byte) error {
+	var fields map[string]json.RawMessage
+	if DecodeStrict(data, &fields) != nil || len(fields) != 2 || fields["name"] == nil || fields["pressed"] == nil {
+		return ErrProtocol
+	}
+	var value struct {
+		Name    string `json:"name"`
+		Pressed *bool  `json:"pressed"`
+	}
+	if DecodeStrict(data, &value) != nil || value.Pressed == nil {
+		return ErrProtocol
+	}
+	result := RemoteKey{Name: value.Name, Pressed: *value.Pressed}
+	if !ValidRemoteKey(result) {
+		return ErrProtocol
+	}
+	*key = result
+	return nil
+}
+
+func (request *RemoteKeyRequest) UnmarshalJSON(data []byte) error {
+	var fields map[string]json.RawMessage
+	if DecodeStrict(data, &fields) != nil || len(fields) != 4 || fields["lease"] == nil || fields["epoch"] == nil || fields["sequence"] == nil || fields["key"] == nil {
+		return ErrProtocol
+	}
+	type plain RemoteKeyRequest
+	var value plain
+	if DecodeStrict(data, &value) != nil || !ValidRemoteKeyRequest(RemoteKeyRequest(value)) {
+		return ErrProtocol
+	}
+	*request = RemoteKeyRequest(value)
+	return nil
+}