Customizable keep-alive-interval

include/slipstream.h

@@ -23,7 +23,7 @@ typedef struct st_address_t {
 } address_t;
 
 int picoquic_slipstream_client(int listen_port, struct st_address_t* server_addresses, size_t server_address_count, const char* domain_name,
-                               const char* cc_algo_id, bool gso);
+                               const char* cc_algo_id, bool gso, size_t keep_alive_interval);
 
 int picoquic_slipstream_server(int server_port, const char* pem_cert, const char* pem_key, 
                                struct sockaddr_storage* target_address, const char* domain_name);

src/slipstream_client.c

@@ -658,9 +658,6 @@ static int slipstream_connect(struct sockaddr_storage* server_address,
         return -1;
     }
 
-    // 400ms
-    picoquic_enable_keep_alive(*cnx, 400000);
-
     /* Document connection in client's context */
     client_ctx->cnx = *cnx;
     /* Set the client callback context */
@@ -683,7 +680,7 @@ static int slipstream_connect(struct sockaddr_storage* server_address,
     return ret;
 }
 
-int picoquic_slipstream_client(int listen_port, struct st_address_t* server_addresses, size_t server_address_count, const char* domain_name, const char* cc_algo_id, bool gso) {
+int picoquic_slipstream_client(int listen_port, struct st_address_t* server_addresses, size_t server_address_count, const char* domain_name, const char* cc_algo_id, bool gso, const size_t keep_alive_interval) {
     /* Start: start the QUIC process */
     int ret = 0;
     uint64_t current_time = 0;
@@ -747,6 +744,12 @@ int picoquic_slipstream_client(int listen_port, struct st_address_t* server_addr
         return -1;
     }
 
+    if (keep_alive_interval != 0) {
+        picoquic_enable_keep_alive(cnx, keep_alive_interval * 1000);
+    } else {
+        picoquic_disable_keep_alive(cnx);
+    }
+
     // Create listening socket
     client_ctx.listen_sock = socket(AF_INET, SOCK_STREAM, 0);
     if (client_ctx.listen_sock < 0) {

src/slipstream_client_cli.c

@@ -22,6 +22,7 @@ static struct argp_option options[] = {
     {"congestion-control", 'c', "ALGO", 0, "Congestion control algorithm (bbr, dcubic) (default: dcubic)", 0},
     {"gso",             'g', "BOOL", OPTION_ARG_OPTIONAL, "GSO enabled (true/false) (default: false). Use --gso or --gso=true to enable.", 0},
     {"domain",          'd', "DOMAIN", 0, "Domain name used for the covert channel (Required)", 0},
+    {"keep-alive-interval", 't', "MS", 0, "Send keep alive pings at this interval (default: 400, disabled: 0)", 0},
     {0} // End of options
 };
 
@@ -33,6 +34,7 @@ struct arguments {
     size_t resolver_count;
     char* cc_algo_id;
     bool gso;
+    size_t keep_alive_interval;
 };
 
 /* Client mode parser */
@@ -97,6 +99,13 @@ static error_t parse_opt(int key, char* arg, struct argp_state* state) {
              argp_error(state, "Invalid boolean value for --gso: '%s'. Use 'true' or 'false'.", arg);
         }
         break;
+    case 't':
+        arguments->keep_alive_interval = atoi(arg);
+        if (arguments->keep_alive_interval < 0) {
+            argp_error(state, "Invalid keep alive interval: %s", arg);
+        }
+        break;
+
     case ARGP_KEY_ARG:
         // No positional arguments expected
         argp_usage(state);
@@ -130,6 +139,7 @@ int main(int argc, char** argv) {
     arguments.gso = false;        // Default GSO state
     arguments.resolver_addresses = NULL;
     arguments.resolver_count = 0;
+    arguments.keep_alive_interval = 400; // Default keep alive interval
 
     // Ensure output buffers are flushed immediately (useful for debugging/logging)
     setbuf(stdout, NULL);
@@ -165,7 +175,8 @@ int main(int argc, char** argv) {
         arguments.resolver_count,
         arguments.domain_name,
         arguments.cc_algo_id,
-        arguments.gso
+        arguments.gso,
+        arguments.keep_alive_interval
     );
 
     // Free allocated memory for resolver addresses