(svn r17999) -Fix: [NewGRF] Improve parsing of RIFF data. Skip unknown chunks and check chunk sizes.

This commit is contained in:
frosch 2009-11-07 18:22:00 +00:00
parent c341673cd5
commit 1519f7074f
1 changed files with 41 additions and 12 deletions

View File

@ -5088,7 +5088,7 @@ static void GRFImportBlock(byte *buf, int len)
}
}
static void LoadGRFSound(byte *buf, int len)
static void LoadGRFSound(byte *buf, uint len)
{
byte *buf_start = buf;
@ -5101,22 +5101,31 @@ static void LoadGRFSound(byte *buf, int len)
return;
}
/* Size of file -- we ignore this */
grf_load_dword(&buf);
uint32 total_size = grf_load_dword(&buf);
if (total_size > len + 8) {
grfmsg(1, "LoadGRFSound: RIFF was truncated");
return;
}
if (grf_load_dword(&buf) != BSWAP32('WAVE')) {
grfmsg(1, "LoadGRFSound: Invalid RIFF type");
return;
}
for (;;) {
while (total_size >= 8) {
uint32 tag = grf_load_dword(&buf);
uint32 size = grf_load_dword(&buf);
total_size -= 8;
if (total_size < size) {
grfmsg(1, "LoadGRFSound: Invalid RIFF");
return;
}
total_size -= size;
switch (tag) {
case ' tmf': // 'fmt '
/* Audio format, must be 1 (PCM) */
if (grf_load_word(&buf) != 1) {
if (size < 16 || grf_load_word(&buf) != 1) {
grfmsg(1, "LoadGRFSound: Invalid audio format");
return;
}
@ -5126,8 +5135,8 @@ static void LoadGRFSound(byte *buf, int len)
grf_load_word(&buf);
sound->bits_per_sample = grf_load_word(&buf);
/* Consume any extra bytes */
for (; size > 16; size--) grf_load_byte(&buf);
/* The rest will be skipped */
size -= 16;
break;
case 'atad': // 'data'
@ -5140,13 +5149,21 @@ static void LoadGRFSound(byte *buf, int len)
sound->priority = 0;
grfmsg(2, "LoadGRFSound: channels %u, sample rate %u, bits per sample %u, length %u", sound->channels, sound->rate, sound->bits_per_sample, size);
return;
return; // the fmt chunk has to appear before data, so we are finished
default:
sound->file_size = 0;
return;
/* Skip unknown chunks */
break;
}
/* Skip rest of chunk */
for (; size > 0; size--) grf_load_byte(&buf);
}
grfmsg(1, "LoadGRFSound: RIFF does not contain any sound data");
/* Clear everything that was read */
MemSetT(sound, 0);
}
/* Action 0x12 */
@ -5285,22 +5302,34 @@ static void TranslateGRFStrings(byte *buf, size_t len)
/* 'Action 0xFF' */
static void GRFDataBlock(byte *buf, int len)
{
/* <FF> <name_len> <name> '\0' <data> */
if (_grf_data_blocks == 0) {
grfmsg(2, "GRFDataBlock: unexpected data block, skipping");
return;
}
if (!check_length(len, 3, "GRFDataBlock")) return;
buf++;
uint8 name_len = grf_load_byte(&buf);
const char *name = (const char *)buf;
buf += name_len + 1;
buf += name_len;
/* Test string termination */
if (grf_load_byte(&buf) != 0) {
grfmsg(2, "GRFDataBlock: Name not properly terminated");
return;
}
if (!check_length(len, 3 + name_len, "GRFDataBlock")) return;
grfmsg(2, "GRFDataBlock: block name '%s'...", name);
_grf_data_blocks--;
switch (_grf_data_type) {
case GDT_SOUND: LoadGRFSound(buf, len - name_len - 2); break;
case GDT_SOUND: LoadGRFSound(buf, len - name_len - 3); break;
default: NOT_REACHED();
}
}