iconvdata/unicode.c

   1 /* Conversion module for Unicode
   2    Copyright (C) 1999, 2000-2002 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1999.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #include <byteswap.h>
  22 #include <dlfcn.h>
  23 #include <gconv.h>
  24 #include <stddef.h>
  25 #include <stdint.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29 /* This is the Byte Order Mark character (BOM).  */
  30 #define BOM     0xfeff
  31 /* And in the other endian format.  */
  32 #define BOM_OE  0xfffe
  33
  34
  35 /* Definitions used in the body of the `gconv' function.  */
  36 #define FROM_LOOP               from_unicode_loop
  37 #define TO_LOOP                 to_unicode_loop
  38 #define DEFINE_INIT             0
  39 #define DEFINE_FINI             0
  40 #define MIN_NEEDED_FROM         2
  41 #define MIN_NEEDED_TO           4
  42 #define FROM_DIRECTION          (dir == from_unicode)
  43 #define PREPARE_LOOP \
  44   enum direction dir = ((struct unicode_data *) step->__data)->dir;           \
  45   int swap;                                                                   \
  46   if (FROM_DIRECTION)                                                         \
  47     {                                                                         \
  48       if (data->__invocation_counter == 0)                                    \
  49         {                                                                     \
  50           /* We have to find out which byte order the file is encoded in.  */ \
  51           if (inptr + 2 > inend)                                              \
  52             return __GCONV_EMPTY_INPUT;                                       \
  53                                                                               \
  54           if (get16u (inptr) == BOM)                                          \
  55             /* Simply ignore the BOM character.  */                           \
  56             *inptrp = inptr += 2;                                             \
  57           else if (get16u (inptr) == BOM_OE)                                  \
  58             {                                                                 \
  59               ((struct unicode_data *) step->__data)->swap = 1;               \
  60               *inptrp = inptr += 2;                                           \
  61             }                                                                 \
  62         }                                                                     \
  63     }                                                                         \
  64   else if (!data->__internal_use && data->__invocation_counter == 0)          \
  65     {                                                                         \
  66       /* Emit the Byte Order Mark.  */                                        \
  67       if (__builtin_expect (outbuf + 2 > outend, 0))                          \
  68         return __GCONV_FULL_OUTPUT;                                           \
  69                                                                               \
  70       put16u (outbuf, BOM);                                                   \
  71       outbuf += 2;                                                            \
  72     }                                                                         \
  73   swap = ((struct unicode_data *) step->__data)->swap;
  74 #define EXTRA_LOOP_ARGS         , swap
  75
  76
  77 /* Direction of the transformation.  */
  78 enum direction
  79 {
  80   illegal_dir,
  81   to_unicode,
  82   from_unicode
  83 };
  84
  85 struct unicode_data
  86 {
  87   enum direction dir;
  88   int swap;
  89 };
  90
  91
  92 extern int gconv_init (struct __gconv_step *step);
  93 int
  94 gconv_init (struct __gconv_step *step)
  95 {
  96   /* Determine which direction.  */
  97   struct unicode_data *new_data;
  98   enum direction dir = illegal_dir;
  99   int result;
 100
 101   if (strcmp (step->__from_name, "UNICODE//") == 0)
 102     dir = from_unicode;
 103   else
 104     dir = to_unicode;
 105
 106   new_data = (struct unicode_data *) malloc (sizeof (struct unicode_data));
 107
 108   result = __GCONV_NOMEM;
 109   if (new_data != NULL)
 110     {
 111       new_data->dir = dir;
 112       new_data->swap = 0;
 113       step->__data = new_data;
 114
 115       if (dir == from_unicode)
 116         {
 117           step->__min_needed_from = MIN_NEEDED_FROM;
 118           step->__max_needed_from = MIN_NEEDED_FROM;
 119           step->__min_needed_to = MIN_NEEDED_TO;
 120           step->__max_needed_to = MIN_NEEDED_TO;
 121         }
 122       else
 123         {
 124           step->__min_needed_from = MIN_NEEDED_TO;
 125           step->__max_needed_from = MIN_NEEDED_TO;
 126           step->__min_needed_to = MIN_NEEDED_FROM;
 127           step->__max_needed_to = MIN_NEEDED_FROM;
 128         }
 129
 130       step->__stateful = 0;
 131
 132       result = __GCONV_OK;
 133     }
 134
 135   return result;
 136 }
 137
 138
 139 extern void gconv_end (struct __gconv_step *data);
 140 void
 141 gconv_end (struct __gconv_step *data)
 142 {
 143   free (data->__data);
 144 }
 145
 146
 147 /* Convert from the internal (UCS4-like) format to UCS2.  */
 148 #define MIN_NEEDED_INPUT        MIN_NEEDED_TO
 149 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_FROM
 150 #define LOOPFCT                 TO_LOOP
 151 #define BODY \
 152   {                                                                           \
 153     uint32_t c = get32 (inptr);                                               \
 154                                                                               \
 155     if (__builtin_expect (c >= 0x10000, 0))                                   \
 156       {                                                                       \
 157         UNICODE_TAG_HANDLER (c, 4);                                           \
 158         STANDARD_TO_LOOP_ERR_HANDLER (4);                                     \
 159       }                                                                       \
 160     else if (__builtin_expect (c >= 0xd800 && c < 0xe000, 0))                 \
 161       {                                                                       \
 162         /* Surrogate characters in UCS-4 input are not valid.                 \
 163            We must catch this, because the UCS-2 output might be              \
 164            interpreted as UTF-16 by other programs.  If we let                \
 165            surrogates pass through, attackers could make a security           \
 166            hole exploit by synthesizing any desired plane 1-16                \
 167            character.  */                                                     \
 168         result = __GCONV_ILLEGAL_INPUT;                                       \
 169         if (! ignore_errors_p ())                                             \
 170           break;                                                              \
 171         inptr += 4;                                                           \
 172         ++*irreversible;                                                      \
 173         continue;                                                             \
 174       }                                                                       \
 175     else                                                                      \
 176       {                                                                       \
 177         put16 (outptr, c);                                                    \
 178         outptr += 2;                                                          \
 179       }                                                                       \
 180                                                                               \
 181     inptr += 4;                                                               \
 182   }
 183 #define LOOP_NEED_FLAGS
 184 #define EXTRA_LOOP_DECLS \
 185         , int swap
 186 #include <iconv/loop.c>
 187
 188
 189 /* Convert from UCS2 to the internal (UCS4-like) format.  */
 190 #define MIN_NEEDED_INPUT        MIN_NEEDED_FROM
 191 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_TO
 192 #define LOOPFCT                 FROM_LOOP
 193 #define BODY \
 194   {                                                                           \
 195     uint16_t u1 = get16 (inptr);                                              \
 196                                                                               \
 197     if (swap)                                                                 \
 198       u1 = bswap_16 (u1);                                                     \
 199                                                                               \
 200     if (__builtin_expect (u1 >= 0xd800 && u1 < 0xe000, 0))                    \
 201       {                                                                       \
 202         /* Surrogate characters in UCS-2 input are not valid.  Reject         \
 203            them.  (Catching this here is not security relevant.)  */          \
 204         STANDARD_FROM_LOOP_ERR_HANDLER (2);                                   \
 205       }                                                                       \
 206                                                                               \
 207     put32 (outptr, u1);                                                       \
 208                                                                               \
 209     inptr += 2;                                                               \
 210     outptr += 4;                                                              \
 211   }
 212 #define LOOP_NEED_FLAGS
 213 #define EXTRA_LOOP_DECLS \
 214         , int swap
 215 #include <iconv/loop.c>
 216
 217
 218 /* Now define the toplevel functions.  */
 219 #include <iconv/skeleton.c>