modules/afcp.c

   1 // This file is part of Deark.
   2 // Copyright (C) 2019 Jason Summers
   3 // See the file COPYING for terms of use.
   4
   5 // AFCP metadata
   6 // (AXS File Concatenation Protocol)
   7
   8 #include <deark-config.h>
   9 #include <deark-private.h>
  10 #include <deark-fmtutil.h>
  11 DE_DECLARE_MODULE(de_module_afcp);
  12
  13 #define CODE_IPTC 0x49505443U
  14 #define CODE_Nail 0x4e61696cU
  15 #define CODE_PrVw 0x50725677U
  16
  17 struct afcpctx {
  18         int is_le;
  19         u8 endian_code;
  20         i64 endpos;
  21         i64 start_tag_offs;
  22         i64 record_count;
  23 };
  24
  25 struct afcprecord {
  26         i64 dlen;
  27         i64 dpos;
  28         struct de_fourcc id4cc;
  29 };
  30
  31 static int do_afcprec_thumbnail(deark *c, struct afcpctx *d, struct afcprecord *ar)
  32 {
  33         unsigned int recver;
  34         i64 pos = ar->dpos;
  35         i64 w, h;
  36         i64 foundpos = 0;
  37         struct de_fourcc imgtype;
  38         const char *ext;
  39         int ret;
  40         int retval = 0;
  41
  42         if(ar->dlen<10) goto done;
  43         recver = (unsigned int)dbuf_getu16x(c->infile, pos, d->is_le);
  44         pos += 2;
  45         de_dbg(c, "record version: %u", recver);
  46         if(recver!=1) goto done;
  47
  48         w = dbuf_getu16x(c->infile, pos, d->is_le);
  49         pos += 2;
  50         h = dbuf_getu16x(c->infile, pos, d->is_le);
  51         pos += 2;
  52         de_dbg(c, "reported dimensions: %d"DE_CHAR_TIMES"%d", (int)w, (int)h);
  53         // Nothing after this point is adequately documented in the spec.
  54
  55         dbuf_read_fourcc(c->infile, pos, &imgtype, 4, 0);
  56         pos += 4;
  57         de_dbg(c, "image type: '%s'", imgtype.id_dbgstr);
  58
  59         ret = dbuf_search(c->infile, (const u8*)"\xff\xd8\xff", 3, pos,
  60                 ar->dpos + ar->dlen - pos, &foundpos);
  61         if(!ret) {
  62                 de_dbg(c, "[failed to find thumbnail image data]");
  63                 goto done;
  64         }
  65         if(ar->id4cc.id==CODE_PrVw) ext = "afcppreview.jpg";
  66         else ext = "afcpthumb.jpg";
  67         dbuf_create_file_from_slice(c->infile, foundpos, ar->dpos + ar->dlen - foundpos, ext,
  68                 NULL, DE_CREATEFLAG_IS_AUX);
  69
  70         retval = 1;
  71 done:
  72         return retval;
  73 }
  74
  75 static void do_afcp_record(deark *c, struct afcpctx *d, i64 pos)
  76 {
  77         struct afcprecord *ar = NULL;
  78
  79         ar = de_malloc(c, sizeof(struct afcprecord));
  80         dbuf_read_fourcc(c->infile, pos, &ar->id4cc, 4, 0);
  81         de_dbg(c, "id: '%s'", ar->id4cc.id_dbgstr);
  82         ar->dlen = dbuf_getu32x(c->infile, pos+4, d->is_le);
  83         de_dbg(c, "dlen: %"I64_FMT, ar->dlen);
  84         ar->dpos = dbuf_getu32x(c->infile, pos+8, d->is_le);
  85         de_dbg(c, "dpos: %"I64_FMT, ar->dpos);
  86         if(ar->dpos<d->start_tag_offs || ar->dpos+ar->dlen>d->endpos) goto done;
  87
  88         if(ar->id4cc.id==CODE_IPTC) {
  89                 de_dbg(c, "IPTC-IIM data");
  90                 de_dbg_indent(c, 1);
  91                 fmtutil_handle_iptc(c, c->infile, ar->dpos, ar->dlen, 0x0);
  92                 de_dbg_indent(c, -1);
  93         }
  94         else if(ar->id4cc.id==CODE_Nail || ar->id4cc.id==CODE_PrVw) {
  95                 do_afcprec_thumbnail(c, d, ar);
  96         }
  97         else {
  98                 if(c->debug_level>=2) {
  99                         de_dbg_hexdump(c, c->infile, ar->dpos, ar->dlen, 256, NULL, 0x1);
 100                 }
 101         }
 102 done:
 103         de_free(c, ar);
 104 }
 105
 106 static void do_afcp_recordlist(deark *c, struct afcpctx *d)
 107 {
 108         int saved_indent_level;
 109         i64 pos;
 110         i64 i;
 111
 112         de_dbg_indent_save(c, &saved_indent_level);
 113         pos = d->start_tag_offs + 12;
 114         de_dbg(c, "record list at %"I64_FMT, pos);
 115
 116         de_dbg_indent(c, 1);
 117         for(i=0; i<d->record_count; i++) {
 118                 if(i+12 > d->endpos) goto done;
 119                 de_dbg(c, "record[%d] at %"I64_FMT, (int)i, pos);
 120                 de_dbg_indent(c, 1);
 121                 do_afcp_record(c, d, pos);
 122                 de_dbg_indent(c, -1);
 123                 pos += 12;
 124         }
 125
 126 done:
 127         de_dbg_indent_restore(c, saved_indent_level);
 128 }
 129
 130 static int do_afcp_starttagrec(deark *c, struct afcpctx *d)
 131 {
 132         int retval = 0;
 133         int saved_indent_level;
 134         unsigned int version;
 135
 136         de_dbg_indent_save(c, &saved_indent_level);
 137         de_dbg(c, "start tag record at %"I64_FMT, d->start_tag_offs);
 138         de_dbg_indent(c, 1);
 139         if(de_getbyte(d->start_tag_offs+3)!=d->endian_code) {
 140                 de_err(c, "AFCP start tag not found at %"I64_FMT, d->start_tag_offs);
 141                 goto done;
 142         }
 143         version = (unsigned int)dbuf_getu16x(c->infile, d->start_tag_offs+4, d->is_le);
 144         de_dbg(c, "version: %u", version);
 145         d->record_count = dbuf_getu16x(c->infile, d->start_tag_offs+6, d->is_le);
 146         de_dbg(c, "record count: %d", (int)d->record_count);
 147
 148         if(version>1) {
 149                 de_warn(c, "Unexpected AFCP version number: %u", version);
 150         }
 151
 152         retval = 1;
 153 done:
 154         de_dbg_indent_restore(c, saved_indent_level);
 155         return retval;
 156 }
 157
 158 static int do_afcp_eofrec(deark *c, struct afcpctx *d)
 159 {
 160         i64 eofrecpos;
 161         int retval = 0;
 162         int saved_indent_level;
 163
 164         de_dbg_indent_save(c, &saved_indent_level);
 165
 166         eofrecpos = d->endpos - 12;
 167         de_dbg(c, "EOF record at %"I64_FMT, eofrecpos);
 168         de_dbg_indent(c, 1);
 169         d->endian_code = de_getbyte(eofrecpos+3);
 170         if(d->endian_code=='*') d->is_le = 1;
 171         else if(d->endian_code=='!') d->is_le = 0;
 172         else {
 173                 de_err(c, "Invalid AFCP format");
 174                 goto done;
 175         }
 176         de_dbg(c, "is-little-endian: %d", d->is_le);
 177
 178         d->start_tag_offs = dbuf_getu32x(c->infile, eofrecpos+4, d->is_le);
 179         de_dbg(c, "start tag offset: %"I64_FMT, d->start_tag_offs);
 180
 181         retval = 1;
 182 done:
 183         de_dbg_indent_restore(c, saved_indent_level);
 184         return retval;
 185 }
 186
 187 static void de_run_afcp(deark *c, de_module_params *mparams)
 188 {
 189         struct afcpctx *d = NULL;
 190         int saved_indent_level;
 191
 192         de_dbg_indent_save(c, &saved_indent_level);
 193         d = de_malloc(c, sizeof(struct afcpctx));
 194         d->endpos = c->infile->len;
 195         de_dbg(c, "AFCP data, ending at %"I64_FMT, d->endpos);
 196         de_dbg_indent(c, 1);
 197
 198         if(!do_afcp_eofrec(c, d)) goto done;
 199         if(!do_afcp_starttagrec(c, d)) goto done;
 200         do_afcp_recordlist(c, d);
 201
 202 done:
 203         de_free(c, d);
 204         de_dbg_indent_restore(c, saved_indent_level);
 205 }
 206
 207 void de_module_afcp(deark *c, struct deark_module_info *mi)
 208 {
 209         mi->id = "afcp";
 210         mi->desc = "AXS File Concatenation Protocol";
 211         mi->run_fn = de_run_afcp;
 212         mi->flags |= DE_MODFLAG_HIDDEN;
 213 }