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 (inptr == inend                                            \
  53                     ? __GCONV_EMPTY_INPUT : __GCONV_INCOMPLETE_INPUT);        \
  54                                                                               \
  55           if (get16u (inptr) == BOM)                                          \
  56             /* Simply ignore the BOM character.  */                           \
  57             *inptrp = inptr += 2;                                             \
  58           else if (get16u (inptr) == BOM_OE)                                  \
  59             {                                                                 \
  60               ((struct unicode_data *) step->__data)->swap = 1;               \
  61               *inptrp = inptr += 2;                                           \
  62             }                                                                 \
  63         }                                                                     \
  64     }                                                                         \
  65   else if (!data->__internal_use && data->__invocation_counter == 0)          \
  66     {                                                                         \
  67       /* Emit the Byte Order Mark.  */                                        \
  68       if (__builtin_expect (outbuf + 2 > outend, 0))                          \
  69         return __GCONV_FULL_OUTPUT;                                           \
  70                                                                               \
  71       put16u (outbuf, BOM);                                                   \
  72       outbuf += 2;                                                            \
  73     }                                                                         \
  74   swap = ((struct unicode_data *) step->__data)->swap;
  75 #define EXTRA_LOOP_ARGS         , swap
  76
  77
  78 /* Direction of the transformation.  */
  79 enum direction
  80 {
  81   illegal_dir,
  82   to_unicode,
  83   from_unicode
  84 };
  85
  86 struct unicode_data
  87 {
  88   enum direction dir;
  89   int swap;
  90 };
  91
  92
  93 extern int gconv_init (struct __gconv_step *step);
  94 int
  95 gconv_init (struct __gconv_step *step)
  96 {
  97   /* Determine which direction.  */
  98   struct unicode_data *new_data;
  99   enum direction dir = illegal_dir;
 100   int result;
 101
 102   if (strcmp (step->__from_name, "UNICODE//") == 0)
 103     dir = from_unicode;
 104   else
 105     dir = to_unicode;
 106
 107   new_data = (struct unicode_data *) malloc (sizeof (struct unicode_data));
 108
 109   result = __GCONV_NOMEM;
 110   if (new_data != NULL)
 111     {
 112       new_data->dir = dir;
 113       new_data->swap = 0;
 114       step->__data = new_data;
 115
 116       if (dir == from_unicode)
 117         {
 118           step->__min_needed_from = MIN_NEEDED_FROM;
 119           step->__max_needed_from = MIN_NEEDED_FROM;
 120           step->__min_needed_to = MIN_NEEDED_TO;
 121           step->__max_needed_to = MIN_NEEDED_TO;
 122         }
 123       else
 124         {
 125           step->__min_needed_from = MIN_NEEDED_TO;
 126           step->__max_needed_from = MIN_NEEDED_TO;
 127           step->__min_needed_to = MIN_NEEDED_FROM;
 128           step->__max_needed_to = MIN_NEEDED_FROM;
 129         }
 130
 131       step->__stateful = 0;
 132
 133       result = __GCONV_OK;
 134     }
 135
 136   return result;
 137 }
 138
 139
 140 extern void gconv_end (struct __gconv_step *data);
 141 void
 142 gconv_end (struct __gconv_step *data)
 143 {
 144   free (data->__data);
 145 }
 146
 147
 148 /* Convert from the internal (UCS4-like) format to UCS2.  */
 149 #define MIN_NEEDED_INPUT        MIN_NEEDED_TO
 150 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_FROM
 151 #define LOOPFCT                 TO_LOOP
 152 #define BODY \
 153   {                                                                           \
 154     uint32_t c = get32 (inptr);                                               \
 155                                                                               \
 156     if (__builtin_expect (c >= 0x10000, 0))                                   \
 157       {                                                                       \
 158         UNICODE_TAG_HANDLER (c, 4);                                           \
 159         STANDARD_TO_LOOP_ERR_HANDLER (4);                                     \
 160       }                                                                       \
 161     else if (__builtin_expect (c >= 0xd800 && c < 0xe000, 0))                 \
 162       {                                                                       \
 163         /* Surrogate characters in UCS-4 input are not valid.                 \
 164            We must catch this, because the UCS-2 output might be              \
 165            interpreted as UTF-16 by other programs.  If we let                \
 166            surrogates pass through, attackers could make a security           \
 167            hole exploit by synthesizing any desired plane 1-16                \
 168            character.  */                                                     \
 169         result = __GCONV_ILLEGAL_INPUT;                                       \
 170         if (! ignore_errors_p ())                                             \
 171           break;                                                              \
 172         inptr += 4;                                                           \
 173         ++*irreversible;                                                      \
 174         continue;                                                             \
 175       }                                                                       \
 176     else                                                                      \
 177       {                                                                       \
 178         put16 (outptr, c);                                                    \
 179         outptr += 2;                                                          \
 180       }                                                                       \
 181                                                                               \
 182     inptr += 4;                                                               \
 183   }
 184 #define LOOP_NEED_FLAGS
 185 #define EXTRA_LOOP_DECLS \
 186         , int swap
 187 #include <iconv/loop.c>
 188
 189
 190 /* Convert from UCS2 to the internal (UCS4-like) format.  */
 191 #define MIN_NEEDED_INPUT        MIN_NEEDED_FROM
 192 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_TO
 193 #define LOOPFCT                 FROM_LOOP
 194 #define BODY \
 195   {                                                                           \
 196     uint16_t u1 = get16 (inptr);                                              \
 197                                                                               \
 198     if (swap)                                                                 \
 199       u1 = bswap_16 (u1);                                                     \
 200                                                                               \
 201     if (__builtin_expect (u1 >= 0xd800 && u1 < 0xe000, 0))                    \
 202       {                                                                       \
 203         /* Surrogate characters in UCS-2 input are not valid.  Reject         \
 204            them.  (Catching this here is not security relevant.)  */          \
 205         STANDARD_FROM_LOOP_ERR_HANDLER (2);                                   \
 206       }                                                                       \
 207                                                                               \
 208     put32 (outptr, u1);                                                       \
 209                                                                               \
 210     inptr += 2;                                                               \
 211     outptr += 4;                                                              \
 212   }
 213 #define LOOP_NEED_FLAGS
 214 #define EXTRA_LOOP_DECLS \
 215         , int swap
 216 #include <iconv/loop.c>
 217
 218
 219 /* Now define the toplevel functions.  */
 220 #include <iconv/skeleton.c>