This is the metadata file that ends in ".cnmt{.nca}" or "meta0.ncd". This seems to replace the TMD format.
The official name for CNMT is "PackagedContentMeta".
PackagedContentMetaHeader
This is "nn::ncm::PackagedContentMetaHeader".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | Id |
| 0x8 | 0x4 | Version |
| 0xC | 0x1 | ContentMetaType |
| 0xD | 0x1 | Reserved |
| 0xE | 0x2 | ExtendedHeaderSize |
| 0x10 | 0x2 | ContentCount |
| 0x12 | 0x2 | ContentMetaCount |
| 0x14 | 0x1 | ContentMetaAttributes (0=None, 1=IncludesExFatDriver, 2=Rebootless, 4=Compacted) |
| 0x15 | 0x3 | Reserved |
| 0x18 | 0x4 | RequiredDownloadSystemVersion |
| 0x1C | 0x4 | Reserved |
SystemUpdateMetaExtendedHeader
This is "nn::ncm::SystemUpdateMetaExtendedHeader".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x4 | ExtendedDataSize |
ApplicationMetaExtendedHeader
This is "nn::ncm::ApplicationMetaExtendedHeader".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | PatchId |
| 0x8 | 0x4 | RequiredSystemVersion |
| 0xC | 0x4 | RequiredApplicationVersion |
PatchMetaExtendedHeader
This is "nn::ncm::PatchMetaExtendedHeader".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | ApplicationId |
| 0x8 | 0x4 | RequiredSystemVersion |
| 0xC | 0x4 | ExtendedDataSize |
| 0x10 | 0x8 | Reserved |
AddOnContentMetaExtendedHeader
This is "nn::ncm::AddOnContentMetaExtendedHeader".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | ApplicationId |
| 0x8 | 0x4 | RequiredApplicationVersion |
| 0xC | 0x1 | [15.0.0+] ContentAccessibilities ([1.0.0-14.1.2] Reserved) |
| 0xD | 0x3 | Reserved |
| 0x10 | 0x8 | [15.0.0+] DataPatchId |
DeltaMetaExtendedHeader
This is "nn::ncm::DeltaMetaExtendedHeader".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | ApplicationId |
| 0x8 | 0x4 | ExtendedDataSize |
| 0xC | 0x4 | Reserved |
DataPatchMetaExtendedHeader
This is "nn::ncm::DataPatchMetaExtendedHeader".
This was added with [15.0.0+].
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | DataId |
| 0x8 | 0x8 | ApplicationId |
| 0x10 | 0x4 | RequiredApplicationVersion |
| 0x14 | 0x4 | ExtendedDataSize |
| 0x18 | 0x8 | Reserved |
PackagedContentInfo
This is "nn::ncm::PackagedContentInfo".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x20 | Hash (SHA256 of the referenced content) |
| 0x20 | 0x10 | ContentId |
| 0x30 | [15.0.0+] 0x5 ([1.0.0-14.1.2] 0x6) | Size |
| 0x35 | 0x1 | [15.0.0+] ContentAttributes |
| 0x36 | 0x1 | ContentType (0=Meta, 1=Program, 2=Data, 3=Control, 4=HtmlDocument, 5=LegalInformation, 6=DeltaFragment) |
| 0x37 | 0x1 | IdOffset |
ContentMetaInfo
This is "nn::ncm::ContentMetaInfo".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | Id |
| 0x8 | 0x4 | Version |
| 0xC | 0x1 | ContentMetaType |
| 0xD | 0x1 | ContentMetaAttributes (0=None, 1=IncludesExFatDriver, 2=Rebootless, 4=Compacted) |
| 0xE | 0x2 | Reserved |
This is used for SystemUpdate, see here: NCM_services#ReadEntryMetaRecords.
SystemUpdateMetaExtendedData
This is "nn::ncm::SystemUpdateMetaExtendedData".
If the Version field is 1, the format is:
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x4 | Version |
| 0x4 | 0x4 | VariationCount |
| 0x8 | 0x20 * VariationCount | FirmwareVariationInfo (Version 1) |
If the Version field is 2, the format is:
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x4 | Version |
| 0x4 | 0x4 | VariationCount |
| 0x8 | 0x4 * VariationCount | FirmwareVariationId |
| Variable | 0x20 * VariationCount | FirmwareVariationInfo (Version 2) |
| Variable | 0x10 * MetaCount (from FirmwareVariationInfo (Version 2)) | ContentMetaInfo (if ReferToBase is False) |
FirmwareVariationInfo
This is "FirmwareVariationInfo ".
If the Version field is 1, the format is:
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x4 | FirmwareVariationId |
| 0x4 | 0x1C | Reserved |
If the Version field is 2, the format is:
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x1 | ReferToBase (0=False, 1=True) |
| 0x1 | 0x3 | Reserved |
| 0x4 | 0x4 | MetaCount |
| 0x8 | 0x18 | Reserved |
PatchMetaExtendedData
This is "nn::ncm::PatchMetaExtendedData".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x4 | PatchHistoryHeaderCount |
| 0x4 | 0x4 | PatchDeltaHistoryCount |
| 0x8 | 0x4 | PatchDeltaHeaderCount |
| 0xC | 0x4 | FragmentSetCount |
| 0x10 | 0x4 | PatchHistoryContentInfoCount |
| 0x14 | 0x4 | PatchDeltaPackagedContentInfoCount |
| 0x18 | 0x4 | Reserved |
| 0x1C | 0x38 * PatchHistoryHeaderCount | PatchHistoryHeader |
| Variable | 0x28 * PatchDeltaHistoryCount | PatchDeltaHistory |
| Variable | 0x28 * PatchDeltaHeaderCount | PatchDeltaHeader |
| Variable | 0x34 * FragmentSetCount | FragmentSet |
| Variable | 0x18 * PatchHistoryContentInfoCount | PatchHistoryContentInfo (PackagedContentInfo without the Hash entry) |
| Variable | 0x38 * PatchDeltaPackagedContentInfoCount | PatchDeltaPackagedContentInfo |
| Variable | 0x4 * FragmentIndicatorCount (from FragmentSet) | FragmentIndicator |
PatchHistoryHeader
This is "nn::ncm::PatchHistoryHeader".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x10 | ContentMetaKey |
| 0x10 | 0x20 | Digest |
| 0x30 | 0x2 | ContentInfoCount |
| 0x32 | 0x6 | Reserved |
PatchDeltaHistory
This is "nn::ncm::PatchDeltaHistory".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | SourcePatchId |
| 0x8 | 0x8 | DestinationPatchId |
| 0x10 | 0x4 | SourceVersion |
| 0x14 | 0x4 | DestinationVersion |
| 0x18 | 0x8 | DownloadSize |
| 0x20 | 0x8 | Reserved |
PatchDeltaHeader
This is "nn::ncm::PatchDeltaHeader".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | SourcePatchId |
| 0x8 | 8 | DestinationPatchId |
| 0x10 | 0x4 | SourceVersion |
| 0x14 | 0x4 | DestinationVersion |
| 0x18 | 0x2 | FragmentSetCount |
| 0x1A | 0x6 | Reserved |
| 0x20 | 0x2 | ContentInfoCount |
| 0x22 | 0x6 | Reserved |
FragmentSet
This is "nn::ncm::FragmentSet".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x10 | SourceContentId |
| 0x10 | 0x10 | DestinationContentId |
| 0x20 | 0x6 | SourceSize |
| 0x26 | 0x6 | DestinationSize |
| 0x2C | 0x2 | FragmentIndicatorCount |
| 0x2E | 0x1 | FragmentTargetContentType (0=Meta, 1=Program, 2=Data, 3=Control, 4=HtmlDocument, 5=LegalInformation, 6=DeltaFragment) |
| 0x2F | 0x1 | UpdateType (0=ApplyAsDelta, 1=Overwrite, 2=Create) |
| 0x30 | 0x4 | Reserved |
FragmentIndicator
This is "nn::ncm::FragmentIndicator".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x2 | ContentInfoIndex |
| 0x2 | 0x2 | FragmentIndex |
DeltaMetaExtendedData
This is "nn::ncm::DeltaMetaExtendedData".
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x8 | SourcePatchId |
| 0x8 | 0x8 | DestinationPatchId |
| 0x10 | 0x4 | SourceVersion |
| 0x14 | 0x4 | DestinationVersion |
| 0x18 | 0x2 | FragmentSetCount |
| 0x1A | 0x6 | Reserved |
| 0x20 | 0x34 * FragmentSetCount | FragmentSet |
| Variable | 0x4 * FragmentIndicatorCount (from FragmentSet) | FragmentIndicator |
Digest
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x20 | Digest |
This is a SHA-256 hash always found at the end of the file. The hash is calculated over the CNMT file's contents, but this is only done for the development version of the file which results in its production version counterpart sharing the same hash value.