stream.c

/*
   rdesktop: A Remote Desktop Protocol client.
   Parsing primitives
   Copyright 2017 Henrik Andersson <hean01@cendio.se> for Cendio AB

   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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include <errno.h>
#include <iconv.h>
#include <stdlib.h>

#include "rdesktop.h"

extern char g_codepage[16];

void
s_realloc(STREAM s, unsigned int size)
{
       unsigned char *data;

       if (s->size >= size)
               return;

       data = s->data;
       s->size = size;
       s->data = xrealloc(data, size);
       s->p = s->data + (s->p - data);
       s->end = s->data + (s->end - data);
       s->iso_hdr = s->data + (s->iso_hdr - data);
       s->mcs_hdr = s->data + (s->mcs_hdr - data);
       s->sec_hdr = s->data + (s->sec_hdr - data);
       s->rdp_hdr = s->data + (s->rdp_hdr - data);
       s->channel_hdr = s->data + (s->channel_hdr - data);
}

void
s_reset(STREAM s)
{
  struct stream tmp;
  tmp = *s;
  memset(s, 0, sizeof(struct stream));
  s->size = tmp.size;
  s->end = s->p = s->data = tmp.data;
}


void
s_free(STREAM s)
{
       free(s->data);
       free(s);
}

static iconv_t
local_to_utf16()
{
  iconv_t icv;
  icv = iconv_open(WINDOWS_CODEPAGE, g_codepage);
  if (icv == (iconv_t) - 1)
  {
    logger(Core, Error, "locale_to_utf16(), iconv_open[%s -> %s] fail %p",
	   g_codepage, WINDOWS_CODEPAGE, icv);
    abort();
  }
  return icv;
}

/* Writes a utf16 encoded string into stream excluding null termination.
   This function assumes that input is ASCII compatible, such as UTF-8.
 */
static inline size_t
_out_utf16s(STREAM s, size_t maxlength, const char *string)
{
  static iconv_t icv_local_to_utf16;
  size_t bl, ibl, obl;
  const char *pin;
  char *pout;

  if (string == NULL)
    return 0;

  if (!icv_local_to_utf16)
    {
      icv_local_to_utf16 = local_to_utf16();
    }

  ibl = strlen(string);
  obl = maxlength ? maxlength : s_left(s);
  pin = string;
  pout = (char *) s->p;

  if (iconv(icv_local_to_utf16, (char **) &pin, &ibl, &pout, &obl) == (size_t) - 1)
    {
      logger(Protocol, Error, "out_utf16s(), iconv(2) fail, errno %d", errno);
      abort();
    }

  bl = (unsigned char*)pout - s->p;

  s->p = (unsigned char *)pout;

  return bl;
}

/* Writes a utf16 encoded string into stream including a null
   termination. The length is fixed and defined by width. If result is
   longer than specified width, the string is truncated. pad,
   specifies a character to pad with.
*/
void
out_utf16s_padded(STREAM s, const char *string, size_t length, unsigned char pad)
{
  int i;
  size_t bl;
  bl = _out_utf16s(s, length - 2, string);

  // append utf16 null termination
  out_uint16(s, 0);
  bl += 2;

  for (i = 0; i < (length - bl); i++)
    out_uint8(s, pad);
}

/* Writes a utf16 encoded string into stream including a null
   termination.
*/
void
out_utf16s(STREAM s, const char *string)
{
  _out_utf16s(s, 0, string);

  // append utf16 null termination
  out_uint16(s, 0);
}


/* Writes a utf16 encoded string into stream excluding null
   termination. */
void
out_utf16s_no_eos(STREAM s, const char *string)
{
  _out_utf16s(s, 0, string);
}