Added framework for putting a firewall module into its own thread

1 files changed, 101 insertions, 0 deletions

diff --git a/eurephiafw.c b/eurephiafw.c
index ebdcbe3..47324f7 100644
--- a/eurephiafw.c
+++ b/eurephiafw.c
@@ -19,14 +19,23 @@
  */
 
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <dlfcn.h>
+#include <errno.h>
+#include <signal.h>
+#include <unistd.h>
+#include <pthread.h>
 
 #include "eurephia_struct.h"
 #include "eurephia_log.h"
 #include "eurephiafw.h"
 #include "eurephiafw_intf.h"
 #include "eurephia_getsym.h"
+#include "eurephia_nullsafe.h"
+#include "eurephiafw_intf.h"
+
+#define MQUEUE_NAME "eurephiaFW"
 
 
 int eFW_unload(eurephiaCTX *ctx) {
@@ -88,3 +97,95 @@ int eFW_load(eurephiaCTX *ctx, const char *intf) {
         return 1;
 }
 
+void eFW_StartFirewall(eurephiaCTX *ctx) {
+        struct mq_attr mqattr;
+
+        ctx->fwcfg = (eurephiaFWINTF *) malloc(sizeof(eurephiaFWINTF)+2);
+        memset(ctx->fwcfg, 0, sizeof(eurephiaFWINTF)+2);
+
+
+        // Initialise driver semaphore
+        if( sem_init(&(*ctx->fwcfg).thrdata.semp_driver, 0, 0) != 0 ) {
+                eurephia_log(ctx, LOG_FATAL, 0, "Could not setup semaphore for FW driver: %s", strerror(errno));
+                free_nullsafe(ctx->fwcfg);
+                return;
+        }
+
+        // Start a new thread (with root permissions) - which will do the firewall work
+        pthread_attr_init(&(*ctx->fwcfg).fw_threadattr);
+        pthread_attr_setdetachstate(&(*ctx->fwcfg).fw_threadattr, PTHREAD_CREATE_JOINABLE);
+        if( pthread_create(&(*ctx->fwcfg).fw_thread, &(*ctx->fwcfg).fw_threadattr,
+                           eFW_RunFirewall, (void *) &(*ctx->fwcfg).thrdata) ) {
+                eurephia_log(ctx, LOG_FATAL, 0, "Could not start firewall thread: %s", strerror(errno));
+                free_nullsafe(ctx->fwcfg);
+                return;
+        }
+
+        // Prepare a POSIX Message Queue
+        mqattr.mq_maxmsg = 10;
+        mqattr.mq_msgsize = 1024;
+        mqattr.mq_flags = 0;
+        (*ctx->fwcfg).thrdata.msgq = mq_open(MQUEUE_NAME, O_RDWR | O_CREAT, 0600, &mqattr);
+        if( (*ctx->fwcfg).thrdata.msgq < 0 ) {
+                pthread_kill((*ctx->fwcfg).fw_thread, SIGABRT);
+                eurephia_log(ctx, LOG_FATAL, 0, "Could not open message queue: %s", strerror(errno));
+                free_nullsafe(ctx->fwcfg);
+                return;
+        }
+
+        // Let child have time to settle and create a semaphore for us
+        sleep(1);
+
+        // Indicate for the FW module that we are ready
+        sem_post(&(*ctx->fwcfg).thrdata.semp_driver);
+
+        // Waiting for the FW module to get ready
+        eurephia_log(ctx, LOG_DEBUG, 20, "eFW interface ready, waiting for the eFW module to get ready");
+        sem_wait(&(*ctx->fwcfg).thrdata.semp_module);
+        eurephia_log(ctx, LOG_INFO, 2, "eFW interface initialised.");
+}
+
+void eFW_StopFirewall(eurephiaCTX *ctx) {
+        char buf[50];
+        void *status =  NULL;
+
+        if( ctx->fwcfg == NULL ) {
+                return;
+        }
+
+
+        // Send shutdown message to the firewall module thread
+        snprintf(buf, 48, "FWSHUTDOWN%c", 0);
+        if( mq_send((*ctx->fwcfg).thrdata.msgq, buf, 11, 1) == -1 ) {
+                eurephia_log(ctx, LOG_FATAL, 0, "Could not initiate shutdown on eFW module: %s", strerror(errno));
+                pthread_kill((*ctx->fwcfg).fw_thread, SIGABRT);
+        }
+
+        // Wait for the firewall module thread to finish
+        pthread_attr_destroy(&(*ctx->fwcfg).fw_threadattr);
+        if( pthread_join((*ctx->fwcfg).fw_thread, &status) ) {
+                eurephia_log(ctx, LOG_FATAL, 0, "Could not do thread join on eFW module thread: %s",
+                             strerror(errno));
+                pthread_kill((*ctx->fwcfg).fw_thread, SIGABRT);
+        }
+
+        // Close and remove the message queue used
+        if( mq_close((*ctx->fwcfg).thrdata.msgq) != 0 ) {
+                eurephia_log(ctx, LOG_WARNING, 0, "Could not do close the message queue used for eFW: %s",
+                             strerror(errno));
+        }
+
+        if( mq_unlink(MQUEUE_NAME) != 0 ) {
+                eurephia_log(ctx, LOG_WARNING, 0, "Could not do close the message queue used for eFW: %s",
+                             strerror(errno));
+        }
+
+        // Take down the semaphore we used
+        if( sem_destroy(&ctx->fwcfg->thrdata.semp_driver) != 0 ) {
+                eurephia_log(ctx, LOG_WARNING, 0, "Could not do destroy the driver semaphore for eFW: %s",
+                             strerror(errno));
+        }
+
+        free_nullsafe(ctx->fwcfg);
+}
+