diff --git a/src/utils/os_internal.c b/src/utils/os_internal.c
index 90b6688ad..a810ee88e 100644
--- a/src/utils/os_internal.c
+++ b/src/utils/os_internal.c
@@ -17,9 +17,11 @@
  */
 
 #include "includes.h"
+#include <time.h>
+#include <sys/wait.h>
 
 #undef OS_REJECT_C_LIB_FUNCTIONS
-#include "os.h"
+#include "common.h"
 
 void os_sleep(os_time_t sec, os_time_t usec)
 {
@@ -167,8 +169,8 @@ char * os_rel2abs_path(const char *rel_path)
 		}
 	}
 
-	cwd_len = strlen(cwd);
-	rel_len = strlen(rel_path);
+	cwd_len = os_strlen(cwd);
+	rel_len = os_strlen(rel_path);
 	ret_len = cwd_len + 1 + rel_len + 1;
 	ret = os_malloc(ret_len);
 	if (ret) {
@@ -506,3 +508,57 @@ int os_snprintf(char *str, size_t size, const char *format, ...)
 		str[size - 1] = '\0';
 	return ret;
 }
+
+
+int os_exec(const char *program, const char *arg, int wait_completion)
+{
+	pid_t pid;
+	int pid_status;
+
+	pid = fork();
+	if (pid < 0) {
+		wpa_printf(MSG_ERROR, "fork: %s", strerror(errno));
+		return -1;
+	}
+
+	if (pid == 0) {
+		/* run the external command in the child process */
+		const int MAX_ARG = 30;
+		char *_program, *_arg, *pos;
+		char *argv[MAX_ARG + 1];
+		int i;
+
+		_program = os_strdup(program);
+		_arg = os_strdup(arg);
+
+		argv[0] = _program;
+
+		i = 1;
+		pos = _arg;
+		while (i < MAX_ARG && pos && *pos) {
+			while (*pos == ' ')
+				pos++;
+			if (*pos == '\0')
+				break;
+			argv[i++] = pos;
+			pos = os_strchr(pos, ' ');
+			if (pos)
+				*pos++ = '\0';
+		}
+		argv[i] = NULL;
+
+		execv(program, argv);
+		wpa_printf(MSG_ERROR, "execv: %s", strerror(errno));
+		os_free(_program);
+		os_free(_arg);
+		exit(0);
+		return -1;
+	}
+
+	if (wait_completion) {
+		/* wait for the child process to complete in the parent */
+		waitpid(pid, &pid_status, 0);
+	}
+
+	return 0;
+}