feat: Add SLAB allocator, Ramdisk, Kernel Namespaces, Event Tracing, NetFilter Firewall, 8-Bit Melodies, and Shell Scripting (sh)

include/net/filter.h

@@ -0,0 +1,51 @@
+#ifndef _NET_FILTER_H
+#define _NET_FILTER_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+#define FILTER_MAX_RULES 32
+
+typedef enum {
+    FILTER_ACTION_ACCEPT = 0,
+    FILTER_ACTION_DROP,
+    FILTER_ACTION_REJECT,
+    FILTER_ACTION_LOG
+} filter_action_t;
+
+typedef enum {
+    FILTER_HOOK_PRE_ROUTING = 0,
+    FILTER_HOOK_LOCAL_IN,
+    FILTER_HOOK_FORWARD,
+    FILTER_HOOK_LOCAL_OUT,
+    FILTER_HOOK_POST_ROUTING,
+    FILTER_HOOK_MAX
+} filter_hook_t;
+
+typedef struct filter_rule {
+    uint32_t id;
+    filter_hook_t hook;
+    uint32_t src_ip;
+    uint32_t src_mask;
+    uint32_t dst_ip;
+    uint32_t dst_mask;
+    uint8_t  protocol;
+    uint16_t src_port;
+    uint16_t dst_port;
+    filter_action_t action;
+    uint64_t packet_count;
+    uint64_t byte_count;
+    char comment[32];
+    bool in_use;
+} filter_rule_t;
+
+void filter_init(void);
+int filter_add_rule(filter_hook_t hook, uint8_t proto, uint16_t dst_port, filter_action_t action, const char* comment);
+int filter_delete_rule(uint32_t rule_id);
+filter_action_t filter_evaluate(filter_hook_t hook, uint8_t proto, uint32_t src_ip, uint32_t dst_ip, uint16_t src_port, uint16_t dst_port, size_t len);
+
+size_t filter_get_rule_count(void);
+const filter_rule_t* filter_get_rule(size_t index);
+
+#endif // _NET_FILTER_H