Commit e5ba5fab authored by Jacob Trimble's avatar Jacob Trimble Committed by Michael Niedermayer

avformat/mov: Fix parsing of saio/siaz atoms in encrypted content.

This doesn't support saio atoms with more than one offset.
Signed-off-by: 's avatarJacob Trimble <modmaker@google.com>
Signed-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
parent 7b8daa77
......@@ -114,6 +114,12 @@ typedef struct MOVEncryptionIndex {
// settings will be used.
unsigned int nb_encrypted_samples;
AVEncryptionInfo **encrypted_samples;
uint8_t* auxiliary_info_sizes;
size_t auxiliary_info_sample_count;
uint8_t auxiliary_info_default_size;
size_t* auxiliary_offsets; ///< Absolute seek position
size_t auxiliary_offsets_count;
} MOVEncryptionIndex;
typedef struct MOVFragmentStreamInfo {
......
......@@ -5912,6 +5912,228 @@ static int mov_read_senc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
return 0;
}
static int mov_parse_auxiliary_info(MOVContext *c, MOVStreamContext *sc, AVIOContext *pb, MOVEncryptionIndex *encryption_index)
{
AVEncryptionInfo **sample, **encrypted_samples;
int64_t prev_pos;
size_t sample_count, sample_info_size, i;
int ret = 0;
unsigned int alloc_size = 0;
if (encryption_index->nb_encrypted_samples)
return 0;
sample_count = encryption_index->auxiliary_info_sample_count;
if (encryption_index->auxiliary_offsets_count != 1) {
av_log(c->fc, AV_LOG_ERROR, "Multiple auxiliary info chunks are not supported\n");
return AVERROR_PATCHWELCOME;
}
if (sample_count >= INT_MAX / sizeof(*encrypted_samples))
return AVERROR(ENOMEM);
prev_pos = avio_tell(pb);
if (!(pb->seekable & AVIO_SEEKABLE_NORMAL) ||
avio_seek(pb, encryption_index->auxiliary_offsets[0], SEEK_SET) != encryption_index->auxiliary_offsets[0]) {
av_log(c->fc, AV_LOG_INFO, "Failed to seek for auxiliary info, will only parse senc atoms for encryption info\n");
goto finish;
}
for (i = 0; i < sample_count && !pb->eof_reached; i++) {
unsigned int min_samples = FFMIN(FFMAX(i, 1024 * 1024), sample_count);
encrypted_samples = av_fast_realloc(encryption_index->encrypted_samples, &alloc_size,
min_samples * sizeof(*encrypted_samples));
if (!encrypted_samples) {
ret = AVERROR(ENOMEM);
goto finish;
}
encryption_index->encrypted_samples = encrypted_samples;
sample = &encryption_index->encrypted_samples[i];
sample_info_size = encryption_index->auxiliary_info_default_size
? encryption_index->auxiliary_info_default_size
: encryption_index->auxiliary_info_sizes[i];
ret = mov_read_sample_encryption_info(c, pb, sc, sample, sample_info_size > sc->cenc.per_sample_iv_size);
if (ret < 0)
goto finish;
}
if (pb->eof_reached) {
av_log(c->fc, AV_LOG_ERROR, "Hit EOF while reading auxiliary info\n");
ret = AVERROR_INVALIDDATA;
} else {
encryption_index->nb_encrypted_samples = sample_count;
}
finish:
avio_seek(pb, prev_pos, SEEK_SET);
if (ret < 0) {
for (; i > 0; i--) {
av_encryption_info_free(encryption_index->encrypted_samples[i - 1]);
}
av_freep(&encryption_index->encrypted_samples);
}
return ret;
}
/**
* Tries to read the given number of bytes from the stream and puts it in a
* newly allocated buffer. This reads in small chunks to avoid allocating large
* memory if the file contains an invalid/malicious size value.
*/
static int mov_try_read_block(AVIOContext *pb, size_t size, uint8_t **data)
{
const unsigned int block_size = 1024 * 1024;
uint8_t *buffer = NULL;
unsigned int alloc_size = 0, offset = 0;
while (offset < size) {
unsigned int new_size =
alloc_size >= INT_MAX - block_size ? INT_MAX : alloc_size + block_size;
uint8_t *new_buffer = av_fast_realloc(buffer, &alloc_size, new_size);
unsigned int to_read = FFMIN(size, alloc_size) - offset;
if (!new_buffer) {
av_free(buffer);
return AVERROR(ENOMEM);
}
buffer = new_buffer;
if (avio_read(pb, buffer + offset, to_read) != to_read) {
av_free(buffer);
return AVERROR_INVALIDDATA;
}
offset += to_read;
}
*data = buffer;
return 0;
}
static int mov_read_saiz(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
MOVEncryptionIndex *encryption_index;
MOVStreamContext *sc;
int ret;
unsigned int sample_count;
ret = get_current_encryption_info(c, &encryption_index, &sc);
if (ret != 1)
return ret;
if (encryption_index->nb_encrypted_samples) {
// This can happen if we have both saio/saiz and senc atoms.
av_log(c->fc, AV_LOG_DEBUG, "Ignoring duplicate encryption info in saiz\n");
return 0;
}
if (encryption_index->auxiliary_info_sample_count) {
av_log(c->fc, AV_LOG_ERROR, "Duplicate saiz atom\n");
return AVERROR_INVALIDDATA;
}
avio_r8(pb); /* version */
if (avio_rb24(pb) & 0x01) { /* flags */
if (avio_rb32(pb) != sc->cenc.default_encrypted_sample->scheme) {
av_log(c->fc, AV_LOG_DEBUG, "Ignoring saiz box with non-zero aux_info_type\n");
return 0;
}
if (avio_rb32(pb) != 0) {
av_log(c->fc, AV_LOG_DEBUG, "Ignoring saiz box with non-zero aux_info_type_parameter\n");
return 0;
}
}
encryption_index->auxiliary_info_default_size = avio_r8(pb);
sample_count = avio_rb32(pb);
encryption_index->auxiliary_info_sample_count = sample_count;
if (encryption_index->auxiliary_info_default_size == 0) {
ret = mov_try_read_block(pb, sample_count, &encryption_index->auxiliary_info_sizes);
if (ret < 0) {
av_log(c->fc, AV_LOG_ERROR, "Failed to read the auxiliary info\n");
return ret;
}
}
if (encryption_index->auxiliary_offsets_count) {
return mov_parse_auxiliary_info(c, sc, pb, encryption_index);
}
return 0;
}
static int mov_read_saio(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
uint64_t *auxiliary_offsets;
MOVEncryptionIndex *encryption_index;
MOVStreamContext *sc;
int i, ret;
unsigned int version, entry_count, alloc_size = 0;
ret = get_current_encryption_info(c, &encryption_index, &sc);
if (ret != 1)
return ret;
if (encryption_index->nb_encrypted_samples) {
// This can happen if we have both saio/saiz and senc atoms.
av_log(c->fc, AV_LOG_DEBUG, "Ignoring duplicate encryption info in saio\n");
return 0;
}
if (encryption_index->auxiliary_offsets_count) {
av_log(c->fc, AV_LOG_ERROR, "Duplicate saio atom\n");
return AVERROR_INVALIDDATA;
}
version = avio_r8(pb); /* version */
if (avio_rb24(pb) & 0x01) { /* flags */
if (avio_rb32(pb) != sc->cenc.default_encrypted_sample->scheme) {
av_log(c->fc, AV_LOG_DEBUG, "Ignoring saio box with non-zero aux_info_type\n");
return 0;
}
if (avio_rb32(pb) != 0) {
av_log(c->fc, AV_LOG_DEBUG, "Ignoring saio box with non-zero aux_info_type_parameter\n");
return 0;
}
}
entry_count = avio_rb32(pb);
if (entry_count >= INT_MAX / sizeof(*auxiliary_offsets))
return AVERROR(ENOMEM);
for (i = 0; i < entry_count && !pb->eof_reached; i++) {
unsigned int min_offsets = FFMIN(FFMAX(i, 1024), entry_count);
auxiliary_offsets = av_fast_realloc(
encryption_index->auxiliary_offsets, &alloc_size,
min_offsets * sizeof(*auxiliary_offsets));
if (!auxiliary_offsets) {
av_freep(&encryption_index->auxiliary_offsets);
return AVERROR(ENOMEM);
}
encryption_index->auxiliary_offsets = auxiliary_offsets;
if (version == 0) {
encryption_index->auxiliary_offsets[i] = avio_rb32(pb);
} else {
encryption_index->auxiliary_offsets[i] = avio_rb64(pb);
}
if (c->frag_index.current >= 0) {
encryption_index->auxiliary_offsets[i] += c->fragment.base_data_offset;
}
}
if (pb->eof_reached) {
av_log(c->fc, AV_LOG_ERROR, "Hit EOF while reading saio\n");
av_freep(&encryption_index->auxiliary_offsets);
return AVERROR_INVALIDDATA;
}
encryption_index->auxiliary_offsets_count = entry_count;
if (encryption_index->auxiliary_info_sample_count) {
return mov_parse_auxiliary_info(c, sc, pb, encryption_index);
}
return 0;
}
static int mov_read_schm(MOVContext *c, AVIOContext *pb, MOVAtom atom)
{
AVStream *st;
......@@ -6127,6 +6349,17 @@ static int cenc_filter(MOVContext *mov, MOVStreamContext *sc, AVPacket *pkt, int
}
if (encryption_index) {
if (encryption_index->auxiliary_info_sample_count &&
!encryption_index->nb_encrypted_samples) {
av_log(mov->fc, AV_LOG_ERROR, "saiz atom found without saio\n");
return AVERROR_INVALIDDATA;
}
if (encryption_index->auxiliary_offsets_count &&
!encryption_index->nb_encrypted_samples) {
av_log(mov->fc, AV_LOG_ERROR, "saio atom found without saiz\n");
return AVERROR_INVALIDDATA;
}
if (!encryption_index->nb_encrypted_samples) {
// Full-sample encryption with default settings.
encrypted_sample = sc->cenc.default_encrypted_sample;
......@@ -6271,6 +6504,8 @@ static const MOVParseTableEntry mov_default_parse_table[] = {
{ MKTAG('s','i','n','f'), mov_read_default },
{ MKTAG('f','r','m','a'), mov_read_frma },
{ MKTAG('s','e','n','c'), mov_read_senc },
{ MKTAG('s','a','i','z'), mov_read_saiz },
{ MKTAG('s','a','i','o'), mov_read_saio },
{ MKTAG('s','c','h','m'), mov_read_schm },
{ MKTAG('s','c','h','i'), mov_read_default },
{ MKTAG('t','e','n','c'), mov_read_tenc },
......@@ -6666,6 +6901,8 @@ static void mov_free_encryption_index(MOVEncryptionIndex **index) {
av_encryption_info_free((*index)->encrypted_samples[i]);
}
av_freep(&(*index)->encrypted_samples);
av_freep(&(*index)->auxiliary_info_sizes);
av_freep(&(*index)->auxiliary_offsets);
av_freep(index);
}
......
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