vgmstream/src/meta/hca.c

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#include "meta.h"
#include "hca_keys.h"
#include "../coding/coding.h"
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static void find_hca_key(hca_codec_data * hca_data, unsigned long long * out_keycode, uint16_t subkey);
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VGMSTREAM * init_vgmstream_hca(STREAMFILE *streamFile) {
return init_vgmstream_hca_subkey(streamFile, 0x0000);
}
VGMSTREAM * init_vgmstream_hca_subkey(STREAMFILE *streamFile, uint16_t subkey) {
VGMSTREAM * vgmstream = NULL;
hca_codec_data * hca_data = NULL;
unsigned long long keycode = 0;
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/* checks */
if ( !check_extensions(streamFile, "hca"))
return NULL;
if (((uint32_t)read_32bitBE(0x00,streamFile) & 0x7f7f7f7f) != 0x48434100) /* "HCA\0", possibly masked */
goto fail;
/* init vgmstream and library's context, will validate the HCA */
hca_data = init_hca(streamFile);
if (!hca_data) goto fail;
/* find decryption key in external file or preloaded list */
if (hca_data->info.encryptionEnabled) {
uint8_t keybuf[0x08+0x02];
size_t keysize;
keysize = read_key_file(keybuf, 0x08+0x04, streamFile);
if (keysize == 0x08) { /* standard */
keycode = (uint64_t)get_64bitBE(keybuf+0x00);
}
else if (keysize == 0x08+0x02) { /* seed key + AWB subkey */
uint64_t key = (uint64_t)get_64bitBE(keybuf+0x00);
uint16_t sub = (uint16_t)get_16bitBE(keybuf+0x08);
keycode = key * ( ((uint64_t)sub << 16u) | ((uint16_t)~sub + 2u) );
}
else {
find_hca_key(hca_data, &keycode, subkey);
}
clHCA_SetKey(hca_data->handle, keycode); //maybe should be done through hca_decoder.c?
}
/* build the VGMSTREAM */
vgmstream = allocate_vgmstream(hca_data->info.channelCount, hca_data->info.loopEnabled);
if (!vgmstream) goto fail;
vgmstream->meta_type = meta_HCA;
vgmstream->sample_rate = hca_data->info.samplingRate;
vgmstream->num_samples = hca_data->info.blockCount * hca_data->info.samplesPerBlock -
hca_data->info.encoderDelay - hca_data->info.encoderPadding;
vgmstream->loop_start_sample = hca_data->info.loopStartBlock * hca_data->info.samplesPerBlock -
hca_data->info.encoderDelay + hca_data->info.loopStartDelay;
vgmstream->loop_end_sample = hca_data->info.loopEndBlock * hca_data->info.samplesPerBlock -
hca_data->info.encoderDelay + (hca_data->info.samplesPerBlock - hca_data->info.loopEndPadding);
/* After loop end CRI's encoder removes the rest of the original samples and puts some
* garbage in the last frame that should be ignored. Optionally it can encode fully preserving
* the file too, but it isn't detectable, so we'll allow the whole thing just in case */
//if (vgmstream->loop_end_sample && vgmstream->num_samples > vgmstream->loop_end_sample)
// vgmstream->num_samples = vgmstream->loop_end_sample;
vgmstream->coding_type = coding_CRI_HCA;
vgmstream->layout_type = layout_none;
vgmstream->codec_data = hca_data;
return vgmstream;
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fail:
free_hca(hca_data);
return NULL;
}
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static inline void test_key(hca_codec_data * hca_data, uint64_t key, uint16_t subkey, int *best_score, uint64_t *best_keycode) {
int score;
if (subkey) {
key = key * ( ((uint64_t)subkey << 16u) | ((uint16_t)~subkey + 2u) );
}
score = test_hca_key(hca_data, (unsigned long long)key);
//;VGM_LOG("HCA: test key=%08x%08x, subkey=%04x, score=%i\n",
// (uint32_t)((key >> 32) & 0xFFFFFFFF), (uint32_t)(key & 0xFFFFFFFF), subkey, score);
/* wrong key */
if (score < 0)
return;
/* update if something better is found */
if (*best_score <= 0 || (score < *best_score && score > 0)) {
*best_score = score;
*best_keycode = key;
}
}
/* Try to find the decryption key from a list. */
static void find_hca_key(hca_codec_data * hca_data, unsigned long long * out_keycode, uint16_t subkey) {
const size_t keys_length = sizeof(hcakey_list) / sizeof(hcakey_info);
int best_score = -1;
int i,j;
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*out_keycode = 0xCC55463930DBE1AB; /* defaults to PSO2 key, most common */
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/* find a candidate key */
for (i = 0; i < keys_length; i++) {
uint64_t key = hcakey_list[i].key;
size_t subkeys_size = hcakey_list[i].subkeys_size;
const uint16_t *subkeys = hcakey_list[i].subkeys;
/* try once with external subkey, if any */
test_key(hca_data, key, subkey, &best_score, out_keycode);
if (best_score == 1) /* best possible score */
goto done;
/* try subkey list */
if (subkeys_size > 0 && subkey == 0) {
for (j = 0; j < subkeys_size; j++) {
test_key(hca_data, key, subkeys[j], &best_score, out_keycode);
if (best_score == 1) /* best possible score */
goto done;
}
}
}
done:
//;VGM_LOG("HCA: best key=%08x%08x (score=%i)\n",
// (uint32_t)((*out_keycode >> 32) & 0xFFFFFFFF), (uint32_t)(*out_keycode & 0xFFFFFFFF), best_score);
VGM_ASSERT(best_score > 1, "HCA: best key=%08x%08x (score=%i)\n",
(uint32_t)((*out_keycode >> 32) & 0xFFFFFFFF), (uint32_t)(*out_keycode & 0xFFFFFFFF), best_score);
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VGM_ASSERT(best_score < 0, "HCA: key not found\n");
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}