/* exif-mnote-data-pentax.c

 *

 * Copyright (c) 2002, 2003 Lutz Mueller <lutz@users.sourceforge.net>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details. 

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

 * Boston, MA  02110-1301  USA.

 *

 * SPDX-License-Identifier: LGPL-2.0-or-later

 */

#include "config.h"

#include "exif-mnote-data-pentax.h"

#include <stdlib.h>

#include <string.h>

#include <stdio.h>

#include <libexif/exif-byte-order.h>

#include <libexif/exif-utils.h>

#define CHECKOVERFLOW(offset,datasize,structsize) (( (offset) >= (datasize)) || ((structsize) > (datasize)) || ((offset) > (datasize) - (structsize) ))

static void

exif_mnote_data_pentax_clear (ExifMnoteDataPentax *n)

{

  ExifMnoteData *d = (ExifMnoteData *) n;

  unsigned int i;

  if (!n) return;

  if (n->entries) {

    for (i = 0; i < n->count; i++)

      if (n->entries[i].data) {

        exif_mem_free (d->mem, n->entries[i].data);

        n->entries[i].data = NULL;

      }

    exif_mem_free (d->mem, n->entries);

    n->entries = NULL;

    n->count = 0;

  }

}

static void

exif_mnote_data_pentax_free (ExifMnoteData *n)

{

  if (!n) return;

  exif_mnote_data_pentax_clear ((ExifMnoteDataPentax *) n);

}

static char *

exif_mnote_data_pentax_get_value (ExifMnoteData *d, unsigned int i, char *val, unsigned int maxlen)

{

  ExifMnoteDataPentax *n = (ExifMnoteDataPentax *) d;

  if (!n) return NULL;

  if (n->count <= i) return NULL;

  return mnote_pentax_entry_get_value (&n->entries[i], val, maxlen);

}

/** 

 * @brief save the MnoteData from ne to buf

 * 

 * @param ne extract the data from this structure 

 * @param *buf write the mnoteData to this buffer (buffer will be allocated)

 * @param buf_size the final size of the buffer

 */

static void

exif_mnote_data_pentax_save (ExifMnoteData *ne,

    unsigned char **buf, unsigned int *buf_size)

{

  ExifMnoteDataPentax *n = (ExifMnoteDataPentax *) ne;

  size_t i, datao,

    base = 0, /* internal MakerNote tag number offset */

    o2 = 4 + 2;   /* offset to first tag entry, past header */

  if (!n || !buf || !buf_size) return;

  datao = n->offset; /* this MakerNote style uses offsets

            based on main IFD, not makernote IFD */

  /*

   * Allocate enough memory for header, the number of entries, entries,

   * and next IFD pointer

   */

  *buf_size = o2 + 2 + n->count * 12 + 4;

  switch (n->version) {

  case casioV2:

    base = MNOTE_PENTAX2_TAG_BASE;

    *buf = exif_mem_alloc (ne->mem, *buf_size);

    if (!*buf) {

      EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataPentax", *buf_size);

      return;

    }

    /* Write the magic header */

    strcpy ((char *)*buf, "QVC");

    exif_set_short (*buf + 4, n->order, (ExifShort) 0);

    break;

  case pentaxV3:

    base = MNOTE_PENTAX2_TAG_BASE;

    *buf = exif_mem_alloc (ne->mem, *buf_size);

    if (!*buf) {

      EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataPentax", *buf_size);

      return;

    }

    /* Write the magic header */

    strcpy ((char *)*buf, "AOC");

    exif_set_short (*buf + 4, n->order, (ExifShort) (

      (n->order == EXIF_BYTE_ORDER_INTEL) ?

      ('I' << 8) | 'I' :

      ('M' << 8) | 'M'));

    break;

  case pentaxV2:

    base = MNOTE_PENTAX2_TAG_BASE;

    *buf = exif_mem_alloc (ne->mem, *buf_size);

    if (!*buf) {

      EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataPentax", *buf_size);

      return;

    }

    /* Write the magic header */

    strcpy ((char *)*buf, "AOC");

    exif_set_short (*buf + 4, n->order, (ExifShort) 0);

    break;

  case pentaxV1:

    /* It looks like this format doesn't have a magic header as

     * such, just has a fixed number of entries equal to 0x001b */

    *buf_size -= 6;

    o2 -= 6;

    *buf = exif_mem_alloc (ne->mem, *buf_size);

    if (!*buf) {

      EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataPentax", *buf_size);

      return;

    }

    break;

  default:

    /* internal error */

    return;

  }

  /* Write the number of entries. */

  exif_set_short (*buf + o2, n->order, (ExifShort) n->count);

  o2 += 2;

  /* Save each entry */

  for (i = 0; i < n->count; i++) {

    size_t doff;  /* offset to current data portion of tag */

    size_t s;

    unsigned char *t;

    size_t o = o2 + i * 12;   /* current offset into output buffer */

    exif_set_short (*buf + o + 0, n->order,

        (ExifShort) (n->entries[i].tag - base));

    exif_set_short (*buf + o + 2, n->order,

        (ExifShort) n->entries[i].format);

    exif_set_long  (*buf + o + 4, n->order,

        n->entries[i].components);

    o += 8;

    s = exif_format_get_size (n->entries[i].format) *

            n->entries[i].components;

    if (s > 65536) {

      /* Corrupt data: EXIF data size is limited to the

       * maximum size of a JPEG segment (64 kb).

       */

      continue;

    }

    if (s > 4) {

      size_t ts = *buf_size + s;

      doff = *buf_size;

      t = exif_mem_realloc (ne->mem, *buf,

             sizeof (char) * ts);

      if (!t) {

        EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataPentax", ts);

        return;

      }

      *buf = t;

      *buf_size = ts;

      exif_set_long (*buf + o, n->order, datao + doff);

    } else

      doff = o;

    /* Write the data. */

    if (n->entries[i].data) {

      memcpy (*buf + doff, n->entries[i].data, s);

    } else {

      /* Most certainly damaged input file */

      memset (*buf + doff, 0, s);

    }

  }

  /* Sanity check the buffer size */

  if (*buf_size < (o2 + n->count * 12 + 4)) {

    exif_log (ne->log, EXIF_LOG_CODE_CORRUPT_DATA, "ExifMnoteDataPentax",

      "Buffer overflow");

  }

  /* Reset next IFD pointer */

  exif_set_long (*buf + o2 + n->count * 12, n->order, 0);

}

static void

exif_mnote_data_pentax_load (ExifMnoteData *en,

    const unsigned char *buf, unsigned int buf_size)

{

  ExifMnoteDataPentax *n = (ExifMnoteDataPentax *) en;

  size_t i, tcount, o, datao, base = 0;

  ExifShort c;

  if (!n) return;

  if (!buf || !buf_size) {

    exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA,

        "ExifMnoteDataPentax", "Short MakerNote");

    return;

  }

  datao = 6 + n->offset;

  if (CHECKOVERFLOW(datao, buf_size, 8)) {

    exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA,

        "ExifMnoteDataPentax", "Short MakerNote");

    return;

  }

  /* Detect variant of Pentax/Casio MakerNote found */

  if (!memcmp(buf + datao, "AOC", 4)) {

    if ((buf[datao + 4] == 'I') && (buf[datao + 5] == 'I')) {

      n->version = pentaxV3;

      n->order = EXIF_BYTE_ORDER_INTEL;

    } else if ((buf[datao + 4] == 'M') && (buf[datao + 5] == 'M')) {

      n->version = pentaxV3;

      n->order = EXIF_BYTE_ORDER_MOTOROLA;

    } else {

      /* Uses Casio v2 tags */

      n->version = pentaxV2;

    }

    exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataPentax",

      "Parsing Pentax maker note v%d...", (int)n->version);

    datao += 4 + 2;

    base = MNOTE_PENTAX2_TAG_BASE;

  } else if (!memcmp(buf + datao, "QVC", 4)) {

    exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataPentax",

      "Parsing Casio maker note v2...");

    n->version = casioV2;

    base = MNOTE_CASIO2_TAG_BASE;

    datao += 4 + 2;

  } else {

    /* probably assert(!memcmp(buf + datao, "\x00\x1b", 2)) */

    exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataPentax",

      "Parsing Pentax maker note v1...");

    n->version = pentaxV1;

  }

  /* Read the number of tags */

  c = exif_get_short (buf + datao, n->order);

  datao += 2;

  /* Just use an arbitrary max tag limit here to avoid needing to much memory or time. There are 102 named tags currently.

   * The format allows specifying the same range of memory as often as it can, so this multiplies quickly. */

  if (c > 200) {

    exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA, "ExifMnoteDataPentax", "Too much tags (%d) in Pentax MakerNote", c);

    return;

  }

  /* Remove any old entries */

  exif_mnote_data_pentax_clear (n);

  /* Reserve enough space for all the possible MakerNote tags */

  n->entries = exif_mem_alloc (en->mem, sizeof (MnotePentaxEntry) * c);

  if (!n->entries) {

    EXIF_LOG_NO_MEMORY(en->log, "ExifMnoteDataPentax", sizeof (MnotePentaxEntry) * c);

    return;

  }

  /* Parse all c entries, storing ones that are successfully parsed */

  tcount = 0;

  for (i = c, o = datao; i; --i, o += 12) {

    size_t s;

    memset(&n->entries[tcount], 0, sizeof(MnotePentaxEntry));

    if (CHECKOVERFLOW(o,buf_size,12)) {

      exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA,

          "ExifMnoteDataPentax", "Short MakerNote");

      break;

    }

    n->entries[tcount].tag        = exif_get_short (buf + o + 0, n->order) + base;

    n->entries[tcount].format     = exif_get_short (buf + o + 2, n->order);

    n->entries[tcount].components = exif_get_long  (buf + o + 4, n->order);

    n->entries[tcount].order      = n->order;

    exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnotePentax",

        "Loading entry 0x%x ('%s')...", n->entries[tcount].tag,

        mnote_pentax_tag_get_name (n->entries[tcount].tag));

    /* Check if we overflow the multiplication. Use buf_size as the max size for integer overflow detection,

     * we will check the buffer sizes closer later. */

    if (  exif_format_get_size (n->entries[tcount].format) &&

      buf_size / exif_format_get_size (n->entries[tcount].format) < n->entries[tcount].components

    ) {

      exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA,

          "ExifMnoteDataPentax", "Tag size overflow detected (%u * %lu)", exif_format_get_size (n->entries[tcount].format), n->entries[tcount].components);

      break;

    }

    /*

     * Size? If bigger than 4 bytes, the actual data is not

     * in the entry but somewhere else (offset).

     */

    s = exif_format_get_size (n->entries[tcount].format) *

                                      n->entries[tcount].components;

    n->entries[tcount].size = s;

    if (s) {

      size_t dataofs = o + 8;

      if (s > 4)

        /* The data in this case is merely a pointer */

          dataofs = exif_get_long (buf + dataofs, n->order) + 6;

      if (CHECKOVERFLOW(dataofs, buf_size, s)) {

        exif_log (en->log, EXIF_LOG_CODE_DEBUG,

              "ExifMnoteDataPentax", "Tag data past end "

            "of buffer (%u > %u)", (unsigned)(dataofs + s), buf_size);

        continue;

      }

      n->entries[tcount].data = exif_mem_alloc (en->mem, s);

      if (!n->entries[tcount].data) {

        EXIF_LOG_NO_MEMORY(en->log, "ExifMnoteDataPentax", s);

        continue;

      }

      memcpy (n->entries[tcount].data, buf + dataofs, s);

    }

    /* Tag was successfully parsed */

    ++tcount;

  }

  /* Store the count of successfully parsed tags */

  n->count = tcount;

}

static unsigned int

exif_mnote_data_pentax_count (ExifMnoteData *n)

{

  return n ? ((ExifMnoteDataPentax *) n)->count : 0;

}

static unsigned int

exif_mnote_data_pentax_get_id (ExifMnoteData *d, unsigned int n)

{

  ExifMnoteDataPentax *note = (ExifMnoteDataPentax *) d;

  if (!note) return 0;

  if (note->count <= n) return 0;

  return note->entries[n].tag;

}

static const char *

exif_mnote_data_pentax_get_name (ExifMnoteData *d, unsigned int n)

{

  ExifMnoteDataPentax *note = (ExifMnoteDataPentax *) d;

  if (!note) return NULL;

  if (note->count <= n) return NULL;

  return mnote_pentax_tag_get_name (note->entries[n].tag);

}

static const char *

exif_mnote_data_pentax_get_title (ExifMnoteData *d, unsigned int n)

{

  ExifMnoteDataPentax *note = (ExifMnoteDataPentax *) d;

  if (!note) return NULL;

  if (note->count <= n) return NULL;

  return mnote_pentax_tag_get_title (note->entries[n].tag);

}

static const char *

exif_mnote_data_pentax_get_description (ExifMnoteData *d, unsigned int n)

{

  ExifMnoteDataPentax *note = (ExifMnoteDataPentax *) d;

  if (!note) return NULL;

  if (note->count <= n) return NULL;

  return mnote_pentax_tag_get_description (note->entries[n].tag);

}

static void

exif_mnote_data_pentax_set_offset (ExifMnoteData *d, unsigned int o)

{

  if (d) ((ExifMnoteDataPentax *) d)->offset = o;

}

static void

exif_mnote_data_pentax_set_byte_order (ExifMnoteData *d, ExifByteOrder o)

{

  ExifByteOrder o_orig;

  ExifMnoteDataPentax *n = (ExifMnoteDataPentax *) d;

  unsigned int i;

  if (!n) return;

  o_orig = n->order;

  n->order = o;

  for (i = 0; i < n->count; i++) {

    if (n->entries[i].components && (n->entries[i].size/n->entries[i].components < exif_format_get_size (n->entries[i].format)))

      continue;

    n->entries[i].order = o;

    exif_array_set_byte_order (n->entries[i].format, n->entries[i].data,

        n->entries[i].components, o_orig, o);

  }

}

int

exif_mnote_data_pentax_identify (const ExifData *ed, const ExifEntry *e)

{

  (void) ed;  /* unused */

  if ((e->size >= 8) && !memcmp (e->data, "AOC", 4)) {

    if (((e->data[4] == 'I') && (e->data[5] == 'I')) ||

        ((e->data[4] == 'M') && (e->data[5] == 'M')))

      return pentaxV3;

    else

      /* Uses Casio v2 tags */

      return pentaxV2;

  }

  if ((e->size >= 8) && !memcmp (e->data, "QVC", 4))

    return casioV2;

  /* This isn't a very robust test, so make sure it's done last */

  /* Maybe we should additionally check for a make of Asahi or Pentax */

  if ((e->size >= 2) && (e->data[0] == 0x00) && (e->data[1] == 0x1b))

    return pentaxV1;

  return 0;

}

ExifMnoteData *

exif_mnote_data_pentax_new (ExifMem *mem)

{

  ExifMnoteData *d;

  if (!mem) return NULL;

  d = exif_mem_alloc (mem, sizeof (ExifMnoteDataPentax));

  if (!d) return NULL;

  exif_mnote_data_construct (d, mem);

  /* Set up function pointers */

  d->methods.free            = exif_mnote_data_pentax_free;

  d->methods.set_byte_order  = exif_mnote_data_pentax_set_byte_order;

  d->methods.set_offset      = exif_mnote_data_pentax_set_offset;

  d->methods.load            = exif_mnote_data_pentax_load;

  d->methods.save            = exif_mnote_data_pentax_save;

  d->methods.count           = exif_mnote_data_pentax_count;

  d->methods.get_id          = exif_mnote_data_pentax_get_id;

  d->methods.get_name        = exif_mnote_data_pentax_get_name;

  d->methods.get_title       = exif_mnote_data_pentax_get_title;

  d->methods.get_description = exif_mnote_data_pentax_get_description;

  d->methods.get_value       = exif_mnote_data_pentax_get_value;

  return d;

}