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#include "session.h"
#include "firewall.h"
#include "dns_server.h"
#include "config.h"
#include "esp_log.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include <string.h>
#define SPENT_SECRETS_MAX 100
static const char *TAG = "session";
static session_t s_sessions[SESSION_MAX_CLIENTS];
static int s_session_count = 0;
static char s_spent_secrets[SPENT_SECRETS_MAX][65];
static int s_spent_count = 0;
static int64_t get_time_ms(void)
{
return (int64_t)xTaskGetTickCount() * portTICK_PERIOD_MS;
}
esp_err_t session_manager_init(void)
{
memset(s_sessions, 0, sizeof(s_sessions));
s_session_count = 0;
s_spent_count = 0;
ESP_LOGI(TAG, "Session manager initialized");
return ESP_OK;
}
static void populate_mac(session_t *session, uint32_t client_ip)
{
if (firewall_get_mac_for_ip(client_ip, session->mac, sizeof(session->mac)) != ESP_OK) {
session->mac[0] = '\0';
}
}
session_t *session_create(uint32_t client_ip, uint64_t allotment_ms,
const char *spent_secrets[], int secret_count)
{
session_t *existing = session_find_by_ip(client_ip);
if (existing) {
session_extend(existing, allotment_ms);
for (int i = 0; i < secret_count && s_spent_count < SPENT_SECRETS_MAX; i++) {
strncpy(s_spent_secrets[s_spent_count], spent_secrets[i], 64);
s_spent_secrets[s_spent_count][64] = '\0';
s_spent_count++;
}
return existing;
}
for (int i = 0; i < secret_count; i++) {
if (session_is_secret_spent(spent_secrets[i])) {
ESP_LOGW(TAG, "Duplicate secret rejected");
return NULL;
}
}
if (s_session_count >= SESSION_MAX_CLIENTS) {
for (int i = 0; i < SESSION_MAX_CLIENTS; i++) {
if (!s_sessions[i].active || session_is_expired(&s_sessions[i])) {
session_revoke(&s_sessions[i]);
break;
}
}
}
for (int i = 0; i < SESSION_MAX_CLIENTS; i++) {
if (!s_sessions[i].active) {
s_sessions[i].client_ip = client_ip;
s_sessions[i].allotment_ms = allotment_ms;
s_sessions[i].start_time_ms = get_time_ms();
s_sessions[i].active = true;
s_sessions[i].spent_secret_count = 0;
populate_mac(&s_sessions[i], client_ip);
for (int j = 0; j < secret_count && j < 5; j++) {
strncpy(s_sessions[i].spent_secrets[s_sessions[i].spent_secret_count],
spent_secrets[j], 64);
s_sessions[i].spent_secrets[s_sessions[i].spent_secret_count][64] = '\0';
s_sessions[i].spent_secret_count++;
}
for (int j = 0; j < secret_count && s_spent_count < SPENT_SECRETS_MAX; j++) {
strncpy(s_spent_secrets[s_spent_count], spent_secrets[j], 64);
s_spent_secrets[s_spent_count][64] = '\0';
s_spent_count++;
}
s_session_count++;
firewall_grant_access(client_ip);
esp_ip4_addr_t ip = { .addr = client_ip };
ESP_LOGI(TAG, "Session created: " IPSTR " mac=%s allotment=%llums", IP2STR(&ip),
s_sessions[i].mac[0] ? s_sessions[i].mac : "unknown",
(unsigned long long)allotment_ms);
return &s_sessions[i];
}
}
ESP_LOGW(TAG, "No free session slots");
return NULL;
}
session_t *session_create_bytes(uint32_t client_ip, uint64_t allotment_bytes,
const char *spent_secrets[], int secret_count)
{
session_t *s = session_create(client_ip, 0, spent_secrets, secret_count);
if (s) {
s->allotment_bytes = allotment_bytes;
s->bytes_consumed = 0;
s->allotment_ms = INT64_MAX;
esp_ip4_addr_t ip = { .addr = client_ip };
ESP_LOGI(TAG, "Bytes session created: " IPSTR " allotment=%llu bytes", IP2STR(&ip),
(unsigned long long)allotment_bytes);
}
return s;
}
void session_add_bytes(uint32_t client_ip, uint64_t bytes)
{
session_t *s = session_find_by_ip(client_ip);
if (s && s->active) {
s->bytes_consumed += bytes;
}
}
session_t *session_find_by_ip(uint32_t client_ip)
{
for (int i = 0; i < SESSION_MAX_CLIENTS; i++) {
if (s_sessions[i].active && s_sessions[i].client_ip == client_ip) {
return &s_sessions[i];
}
}
return NULL;
}
session_t *session_find_by_mac(const char *mac)
{
for (int i = 0; i < SESSION_MAX_CLIENTS; i++) {
if (s_sessions[i].active && s_sessions[i].mac[0] != '\0' &&
strcmp(s_sessions[i].mac, mac) == 0) {
return &s_sessions[i];
}
}
return NULL;
}
void session_extend(session_t *session, uint64_t additional_ms)
{
if (!session || !session->active) return;
session->allotment_ms += additional_ms;
esp_ip4_addr_t ip = { .addr = session->client_ip };
ESP_LOGI(TAG, "Session extended: " IPSTR " +%llums (total=%llu)", IP2STR(&ip),
(unsigned long long)additional_ms, (unsigned long long)session->allotment_ms);
}
bool session_is_expired(const session_t *session)
{
if (!session || !session->active) return true;
const tollgate_config_t *cfg = tollgate_config_get();
if (cfg && strcmp(cfg->metric, "bytes") == 0) {
return session->bytes_consumed >= session->allotment_bytes;
}
int64_t elapsed = get_time_ms() - session->start_time_ms;
return elapsed >= (int64_t)session->allotment_ms;
}
bool session_is_secret_spent(const char *secret)
{
for (int i = 0; i < s_spent_count; i++) {
if (strncmp(s_spent_secrets[i], secret, 64) == 0) return true;
}
return false;
}
void session_check_expiry(void)
{
for (int i = 0; i < SESSION_MAX_CLIENTS; i++) {
if (s_sessions[i].active && session_is_expired(&s_sessions[i])) {
esp_ip4_addr_t ip = { .addr = s_sessions[i].client_ip };
ESP_LOGI(TAG, "Session expired: " IPSTR " mac=%s", IP2STR(&ip),
s_sessions[i].mac[0] ? s_sessions[i].mac : "unknown");
session_revoke(&s_sessions[i]);
}
}
}
void session_revoke(session_t *session)
{
if (!session || !session->active) return;
firewall_revoke_access(session->client_ip);
session->active = false;
s_session_count--;
}
void session_revoke_all(void)
{
for (int i = 0; i < SESSION_MAX_CLIENTS; i++) {
if (s_sessions[i].active) {
session_revoke(&s_sessions[i]);
}
}
}
int session_active_count(void)
{
int count = 0;
for (int i = 0; i < SESSION_MAX_CLIENTS; i++) {
if (s_sessions[i].active) count++;
}
return count;
}
void session_tick(void)
{
session_check_expiry();
}
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