feat(server): Add Embedded HTTP Server & REST API, Systemd Service Manager, Multi-User Auth, Syslog, Crond, and Server Metrics

include/drivers/ramdisk.h

@@ -3,7 +3,7 @@
 
 #include <block/block.h>
 
-#define RAMDISK_SIZE (4 * 1024 * 1024) // 4 MB Ramdisk
+#define RAMDISK_SIZE (512 * 1024) // 512 KB Ramdisk (1024 sectors)
 #define RAMDISK_SECTOR_SIZE 512
 
 void ramdisk_init(void);

include/init/service.h

@@ -0,0 +1,44 @@
+#ifndef _INIT_SERVICE_H
+#define _INIT_SERVICE_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+#define MAX_SERVICES 16
+
+typedef enum {
+    SERVICE_STATE_STOPPED = 0,
+    SERVICE_STATE_STARTING,
+    SERVICE_STATE_RUNNING,
+    SERVICE_STATE_STOPPING,
+    SERVICE_STATE_FAILED
+} service_state_t;
+
+typedef int (*service_func_t)(void);
+
+typedef struct service_unit {
+    uint32_t id;
+    char name[32];
+    char description[64];
+    service_state_t state;
+    bool enabled;
+    uint32_t pid;
+    uint64_t start_time;
+    uint32_t restart_count;
+    service_func_t start_fn;
+    service_func_t stop_fn;
+    bool in_use;
+} service_unit_t;
+
+void service_manager_init(void);
+int  service_register(const char* name, const char* desc, service_func_t start_fn, service_func_t stop_fn, bool enable_at_boot);
+int  service_start(const char* name);
+int  service_stop(const char* name);
+int  service_restart(const char* name);
+service_state_t service_get_state(const char* name);
+
+size_t service_get_count(void);
+const service_unit_t* service_get_by_index(size_t index);
+
+#endif // _INIT_SERVICE_H

include/kernel/cron.h

@@ -0,0 +1,28 @@
+#ifndef _KERNEL_CRON_H
+#define _KERNEL_CRON_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+#define MAX_CRON_JOBS 16
+
+typedef struct cron_job {
+    uint32_t id;
+    char command[128];
+    uint32_t interval_sec;
+    uint64_t last_run_tick;
+    uint32_t run_count;
+    bool enabled;
+    bool in_use;
+} cron_job_t;
+
+void cron_init(void);
+int  cron_add_job(const char* command, uint32_t interval_sec);
+int  cron_remove_job(uint32_t id);
+void cron_tick(void);
+
+size_t cron_get_job_count(void);
+const cron_job_t* cron_get_job(size_t index);
+
+#endif // _KERNEL_CRON_H

include/kernel/metrics.h

@@ -0,0 +1,25 @@
+#ifndef _KERNEL_METRICS_H
+#define _KERNEL_METRICS_H
+
+#include <stdint.h>
+#include <stddef.h>
+
+typedef struct system_metrics {
+    uint32_t cpu_user_pct;
+    uint32_t cpu_system_pct;
+    uint32_t cpu_idle_pct;
+    uint64_t mem_total_kb;
+    uint64_t mem_used_kb;
+    uint64_t mem_free_kb;
+    uint64_t net_rx_bytes;
+    uint64_t net_tx_bytes;
+    uint64_t net_rx_packets;
+    uint64_t net_tx_packets;
+    uint64_t disk_read_sectors;
+    uint64_t disk_written_sectors;
+} system_metrics_t;
+
+void metrics_init(void);
+void metrics_sample(system_metrics_t* out);
+
+#endif // _KERNEL_METRICS_H

include/kernel/syslog.h

@@ -0,0 +1,39 @@
+#ifndef _KERNEL_SYSLOG_H
+#define _KERNEL_SYSLOG_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+#define LOG_EMERG   0
+#define LOG_ALERT   1
+#define LOG_CRIT    2
+#define LOG_ERR     3
+#define LOG_WARNING 4
+#define LOG_NOTICE  5
+#define LOG_INFO    6
+#define LOG_DEBUG   7
+
+#define LOG_KERN    (0<<3)
+#define LOG_USER    (1<<3)
+#define LOG_DAEMON  (3<<3)
+#define LOG_AUTH    (4<<3)
+#define LOG_SYSLOG  (5<<3)
+
+#define SYSLOG_BUFFER_SIZE 128
+#define SYSLOG_MSG_MAX     128
+
+typedef struct syslog_entry {
+    uint64_t timestamp;
+    uint8_t  priority;
+    char     facility_str[12];
+    char     ident[24];
+    char     message[SYSLOG_MSG_MAX];
+} syslog_entry_t;
+
+void syslog_init(void);
+void syslog_write(int priority, const char* ident, const char* message);
+size_t syslog_get_count(void);
+const syslog_entry_t* syslog_get_entry(size_t index);
+
+#endif // _KERNEL_SYSLOG_H

include/net/http.h

@@ -0,0 +1,39 @@
+#ifndef _NET_HTTP_H
+#define _NET_HTTP_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+#define HTTP_PORT 80
+#define HTTP_MAX_PAYLOAD 2048
+
+typedef struct http_request {
+    char method[8];      // GET, POST, HEAD
+    char path[128];      // /index.html, /api/status
+    char version[16];   // HTTP/1.1
+    char user_agent[64];
+    uint32_t content_length;
+    char body[HTTP_MAX_PAYLOAD];
+} http_request_t;
+
+typedef struct http_response {
+    int status_code;     // 200, 404, 500
+    char content_type[32]; // text/html, application/json, text/plain
+    char body[HTTP_MAX_PAYLOAD];
+    size_t body_len;
+} http_response_t;
+
+void httpd_init(void);
+int  httpd_start(uint16_t port);
+int  httpd_stop(void);
+bool httpd_is_running(void);
+uint32_t httpd_get_requests_served(void);
+
+// Process a raw HTTP request and generate HTTP response
+int httpd_handle_request(const char* raw_request, char* raw_response, size_t max_resp_len);
+
+// Client operations
+int http_client_get(const char* url, char* response_buf, size_t max_len);
+
+#endif // _NET_HTTP_H

include/security/auth.h

@@ -0,0 +1,34 @@
+#ifndef _SECURITY_AUTH_H
+#define _SECURITY_AUTH_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+#define MAX_USERS 16
+
+typedef struct user_account {
+    uint32_t uid;
+    uint32_t gid;
+    char username[32];
+    char full_name[64];
+    char home_dir[64];
+    char shell[32];
+    char password_hash[65]; // 64-char SHA256 hex string + null
+    bool in_use;
+} user_account_t;
+
+void auth_init(void);
+int  auth_add_user(const char* username, const char* password, uint32_t uid, uint32_t gid, const char* home, const char* shell);
+bool auth_verify_password(const char* username, const char* password);
+int  auth_change_password(const char* username, const char* new_password);
+const user_account_t* auth_get_user_by_name(const char* username);
+const user_account_t* auth_get_user_by_uid(uint32_t uid);
+
+const user_account_t* auth_get_current_user(void);
+int auth_set_current_user(const char* username);
+
+size_t auth_get_user_count(void);
+const user_account_t* auth_get_user_by_index(size_t index);
+
+#endif // _SECURITY_AUTH_H