diff --git a/xrdp/os_calls.c b/xrdp/os_calls.c
new file mode 100644
index 00000000..afa1e8b7
--- /dev/null
+++ b/xrdp/os_calls.c
@@ -0,0 +1,361 @@
+/*
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+   Copyright (C) Jay Sorg 2004
+
+   generic operating system calls
+
+*/
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <pthread.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <netinet/in.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <openssl/rc4.h>
+#include <openssl/md5.h>
+#include <openssl/sha.h>
+#include <openssl/bn.h>
+
+static pthread_mutex_t g_term_mutex = PTHREAD_MUTEX_INITIALIZER;
+static int g_term = 0;
+
+/*****************************************************************************/
+void g_printf(char *format, ...)
+{
+  va_list ap;
+
+  va_start(ap, format);
+  vfprintf(stdout, format, ap);
+  va_end(ap);
+}
+
+/*****************************************************************************/
+/* produce a hex dump */
+void g_hexdump(char* p, int len)
+{
+  unsigned char* line;
+  int i;
+  int thisline;
+  int offset;
+
+  line = (unsigned char*)p;
+  offset = 0;
+  while (offset < len)
+  {
+    printf("%04x ", offset);
+    thisline = len - offset;
+    if (thisline > 16)
+      thisline = 16;
+    for (i = 0; i < thisline; i++)
+      printf("%02x ", line[i]);
+    for (; i < 16; i++)
+      printf("   ");
+    for (i = 0; i < thisline; i++)
+      printf("%c", (line[i] >= 0x20 && line[i] < 0x7f) ? line[i] : '.');
+    printf("\n");
+    offset += thisline;
+    line += thisline;
+  }
+}
+
+/*****************************************************************************/
+void* g_malloc(int size, int zero)
+{
+  void* rv;
+
+  rv = malloc(size);
+  if (zero)
+    memset(rv, 0, size);
+  return rv;
+}
+
+/*****************************************************************************/
+void g_free(void* ptr)
+{
+  if (ptr != 0)
+    free(ptr);
+}
+
+/*****************************************************************************/
+void g_memset(void* ptr, int val, int size)
+{
+  memset(ptr, val, size);
+}
+
+/*****************************************************************************/
+void g_memcpy(void* d_ptr, const void* s_ptr, int size)
+{
+  memcpy(d_ptr, s_ptr, size);
+}
+
+/*****************************************************************************/
+int g_getchar(void)
+{
+  return getchar();
+}
+
+/*****************************************************************************/
+int g_tcp_socket(void)
+{
+  return socket(PF_INET, SOCK_STREAM, 0);
+}
+
+/*****************************************************************************/
+void g_tcp_close(int sck)
+{
+  close(sck);
+}
+
+/*****************************************************************************/
+int g_tcp_set_non_blocking(int sck)
+{
+  int i;
+
+  i = fcntl(sck, F_GETFL);
+  i = i | O_NONBLOCK;
+  fcntl(sck, F_SETFL, i);
+  return 0;
+}
+
+/*****************************************************************************/
+int g_tcp_bind(int sck, char* port)
+{
+  struct sockaddr_in s;
+
+  memset(&s, 0, sizeof(struct sockaddr_in));
+  s.sin_family = AF_INET;
+  s.sin_port = htons(atoi(port));
+  s.sin_addr.s_addr = INADDR_ANY;
+  return bind(sck, (struct sockaddr*)&s, sizeof(struct sockaddr_in));
+}
+
+/*****************************************************************************/
+int g_tcp_listen(int sck)
+{
+  return listen(sck, 2);
+}
+
+/*****************************************************************************/
+int g_tcp_accept(int sck)
+{
+  struct sockaddr_in s;
+  int i;
+
+  i = sizeof(struct sockaddr_in);
+  memset(&s, 0, i);
+  return accept(sck, (struct sockaddr*)&s, (socklen_t*)&i);
+}
+
+/*****************************************************************************/
+int g_tcp_recv(int sck, void* ptr, int len, int flags)
+{
+  return recv(sck, ptr, len, flags);
+}
+
+/*****************************************************************************/
+int g_tcp_send(int sck, void* ptr, int len, int flags)
+{
+  return send(sck, ptr, len, flags);
+}
+
+/*****************************************************************************/
+int g_tcp_last_error_would_block(int sck)
+{
+  return errno == EWOULDBLOCK;
+}
+
+/*****************************************************************************/
+int g_tcp_select(int sck)
+{
+  fd_set rfds;
+
+  FD_ZERO(&rfds);
+  FD_SET(sck, &rfds);
+  return select(sck + 1, &rfds, 0, 0, 0);
+}
+
+/*****************************************************************************/
+int g_is_term(void)
+{
+  int rv;
+
+  pthread_mutex_lock(&g_term_mutex);
+  rv = g_term;
+  pthread_mutex_unlock(&g_term_mutex);
+  return rv;
+}
+
+/*****************************************************************************/
+void g_set_term(int in_val)
+{
+  pthread_mutex_lock(&g_term_mutex);
+  g_term = in_val;
+  pthread_mutex_unlock(&g_term_mutex);
+}
+
+/*****************************************************************************/
+void g_sleep(int msecs)
+{
+  usleep(msecs * 1000);
+}
+
+/*****************************************************************************/
+int g_thread_create(void* (*start_routine)(void*), void* arg)
+{
+  pthread_t thread;
+
+  return pthread_create(&thread, 0, start_routine, arg);
+}
+
+/* rc4 stuff */
+
+/*****************************************************************************/
+void* g_rc4_info_create(void)
+{
+  return g_malloc(sizeof(RC4_KEY), 1);;
+}
+
+/*****************************************************************************/
+void g_rc4_info_delete(void* rc4_info)
+{
+  g_free(rc4_info);
+}
+
+/*****************************************************************************/
+void g_rc4_set_key(void* rc4_info, char* key, int len)
+{
+  RC4_set_key((RC4_KEY*)rc4_info, len, (unsigned char*)key);
+}
+
+/*****************************************************************************/
+void g_rc4_crypt(void* rc4_info, char* data, int len)
+{
+  RC4((RC4_KEY*)rc4_info, len, (unsigned char*)data, (unsigned char*)data);
+}
+
+/* sha1 stuff */
+
+/*****************************************************************************/
+void* g_sha1_info_create(void)
+{
+  return g_malloc(sizeof(SHA_CTX), 1);
+}
+
+/*****************************************************************************/
+void g_sha1_info_delete(void* sha1_info)
+{
+  g_free(sha1_info);
+}
+
+/*****************************************************************************/
+void g_sha1_clear(void* sha1_info)
+{
+  SHA1_Init((SHA_CTX*)sha1_info);
+}
+
+/*****************************************************************************/
+void g_sha1_transform(void* sha1_info, char* data, int len)
+{
+  SHA1_Update((SHA_CTX*)sha1_info, data, len);
+}
+
+/*****************************************************************************/
+void g_sha1_complete(void* sha1_info, char* data)
+{
+  SHA1_Final((unsigned char*)data, (SHA_CTX*)sha1_info);
+}
+
+/* md5 stuff */
+
+/*****************************************************************************/
+void* g_md5_info_create(void)
+{
+  return g_malloc(sizeof(MD5_CTX), 1);
+}
+
+/*****************************************************************************/
+void g_md5_info_delete(void* md5_info)
+{
+  g_free(md5_info);
+}
+
+/*****************************************************************************/
+void g_md5_clear(void* md5_info)
+{
+  MD5_Init((MD5_CTX*)md5_info);
+}
+
+/*****************************************************************************/
+void g_md5_transform(void* md5_info, char* data, int len)
+{
+  MD5_Update((MD5_CTX*)md5_info, data, len);
+}
+
+/*****************************************************************************/
+void g_md5_complete(void* md5_info, char* data)
+{
+  MD5_Final((unsigned char*)data, (MD5_CTX*)md5_info);
+}
+
+/*****************************************************************************/
+int g_mod_exp(char* out, char* in, char* mod, char* exp)
+{
+  BN_CTX* ctx;
+  BIGNUM lmod;
+  BIGNUM lexp;
+  BIGNUM lin;
+  BIGNUM lout;
+  int rv;
+
+  ctx = BN_CTX_new();
+  BN_init(&lmod);
+  BN_init(&lexp);
+  BN_init(&lin);
+  BN_init(&lout);
+  BN_bin2bn((unsigned char*)mod, 64, &lmod);
+  BN_bin2bn((unsigned char*)exp, 64, &lexp);
+  BN_bin2bn((unsigned char*)in, 64, &lin);
+  BN_mod_exp(&lout, &lin, &lexp, &lmod, ctx);
+  rv = BN_bn2bin(&lout, (unsigned char*)out);
+  BN_free(&lin);
+  BN_free(&lout);
+  BN_free(&lexp);
+  BN_free(&lmod);
+  BN_CTX_free(ctx);
+  return rv;
+}
+
+/*****************************************************************************/
+void g_random(char* data, int len)
+{
+  int fd;
+
+  memset(data, 0x44, len);
+  fd = open("/dev/urandom", O_RDONLY);
+  if (fd == -1)
+    fd = open("/dev/random", O_RDONLY);
+  if (fd != -1)
+  {
+    read(fd, data, len);
+    close(fd);
+  }
+}