Capture services

From Nintendo Switch Brew
Jump to navigation Jump to search

caps:a

This is "nn::capsrv::sf::IAlbumAccessorService".

Cmd Name
0 GetAlbumFileCount
1 GetAlbumFileList
2 LoadAlbumFile
3 DeleteAlbumFile
4 StorageCopyAlbumFile
5 IsAlbumMounted
6 GetAlbumUsage
7 GetAlbumFileSize
8 LoadAlbumFileThumbnail
9 [2.0.0+] LoadAlbumScreenShotImage
10 [2.0.0+] LoadAlbumScreenShotThumbnailImage
11 [2.0.0+] GetAlbumEntryFromApplicationAlbumEntry
12 [3.0.0+] LoadAlbumScreenShotImageEx
13 [3.0.0+] LoadAlbumScreenShotThumbnailImageEx
14 [3.0.0+] LoadAlbumScreenShotImageEx0
15 [4.0.0+] GetAlbumUsage3
16 [4.0.0+] GetAlbumMountResult
17 [4.0.0+] GetAlbumUsage16
18 [6.0.0+]
100 [5.0.0+] GetAlbumFileCountEx0
101 [5.0.0+] GetAlbumFileListEx0
202 [1.0.0-2.3.0] SaveEditedScreenShot
301 GetLastOverlayScreenShotThumbnail
302 [4.0.0+] GetLastOverlayMovieThumbnail
401 GetAutoSavingStorage
501 GetRequiredStorageSpaceSizeToCopyAll
1001 [3.0.0+] LoadAlbumScreenShotThumbnailImageEx0
1002 [3.0.0+] LoadAlbumScreenShotImageEx1
1003 [4.0.0+] LoadAlbumScreenShotThumbnailImageEx1
8001 ForceAlbumUnmounted
8002 ResetAlbumMountStatus
8011 RefreshAlbumCache
8012 GetAlbumCache
8013 [4.0.0+] GetAlbumCacheEx
8021 [2.0.0+] GetAlbumEntryFromApplicationAlbumEntryAruid
10011 SetInternalErrorConversionEnabled
50000 [6.0.0+] LoadMakerNoteInfoForDebug
60002 [4.0.0+] OpenAccessorSession

Cmd1002: Takes a total of 0x38-bytes of input, two type-0x5 input buffers, and returns 0x20-bytes of output. [4.0.0+] No longer returns output, and now takes the following buffers instead: type-0x16, type-0x46, and type-0x6.

Cmd60002: Takes a total of 8-bytes of input, a PID, and returns an #IAlbumAccessorSession.

IAlbumAccessorSession

This is "nn::capsrv::sf::IAlbumAccessorSession".

This was added with [4.0.0+].

Cmd Name
2001 OpenAlbumMovieReadStream
2002 CloseAlbumMovieReadStream
2003 GetAlbumMovieReadStreamMovieDataSize
2004 ReadMovieDataFromAlbumMovieReadStream
2005 GetAlbumMovieReadStreamBrokenReason
2006 GetAlbumMovieReadStreamImageDataSize
2007 ReadImageDataFromAlbumMovieReadStream
2008 ReadFileAttributeFromAlbumMovieReadStream

caps:c

This is "nn::capsrv::sf::IAlbumControlService", previously "nn::capsrv::sf::ICaptureControllerService" with [1.0.0].

Cmd Name Notes
[1.0.0] 1 CaptureRawImage
[1.0.0] 2 CaptureRawImageWithTimeout
33 [7.0.0+]
[1.0.0] 1001 RequestTakingScreenShot
[1.0.0] 1002 RequestTakingScreenShotWithTimeout
[1.0.0] 1011 NotifyTakingScreenShotRefused
2001 NotifyAlbumStorageIsAvailable
2002 NotifyAlbumStorageIsUnavailable
2011 [2.0.0+] RegisterAppletResourceUserId
2012 [2.0.0+] UnregisterAppletResourceUserId
2013 [2.0.0+] GetApplicationIdFromAruid
2014 [2.0.0+] CheckApplicationIdRegistered
2101 [2.0.0+] GenerateCurrentAlbumFileId Takes an input u8 and u64, returns a 0x18-byte struct.
2102 [2.0.0+] GenerateApplicationAlbumEnrty
[2.0.0-3.0.2] 2201 SaveAlbumScreenShotFile
2202 [4.0.0+] SaveAlbumScreenShotFileEx
2301 [2.0.0+] SetOverlayScreenShotThumbnailData
2302 [4.0.0+] SetOverlayMovieThumbnailData
60001 [4.0.0+] OpenControlSession Takes a total of 8-bytes of input and a PID, returns an #IAlbumControlSession.

Cmd33

Takes an input u64 #ShimLibraryVersion, an u64 AppletResourceUserId, and a PID, no output.

This is used by caps:su SetShimLibraryVersion.

IAlbumControlSession

This is "nn::capsrv::sf::IAlbumControlSession".

This was added with [4.0.0+].

Cmd Name Notes
2001 OpenAlbumMovieReadStream
2002 CloseAlbumMovieReadStream
2003 GetAlbumMovieReadStreamMovieDataSize
2004 ReadMovieDataFromAlbumMovieReadStream
2005 GetAlbumMovieReadStreamBrokenReason
2006 GetAlbumMovieReadStreamImageDataSize
2007 ReadImageDataFromAlbumMovieReadStream
2008 ReadFileAttributeFromAlbumMovieReadStream
2401 OpenAlbumMovieWriteStream
2402 FinishAlbumMovieWriteStream
2403 CommitAlbumMovieWriteStream
2404 DiscardAlbumMovieWriteStream
2405 DiscardAlbumMovieWriteStreamNoDelete
2406 [7.0.0+]
2411 StartAlbumMovieWriteStreamDataSection
2412 EndAlbumMovieWriteStreamDataSection
2413 StartAlbumMovieWriteStreamMetaSection
2414 EndAlbumMovieWriteStreamMetaSection
2421 ReadDataFromAlbumMovieWriteStream
2422 WriteDataToAlbumMovieWriteStream
2424 WriteMetaToAlbumMovieWriteStream
2431 GetAlbumMovieWriteStreamBrokenReason
2433 GetAlbumMovieWriteStreamDataSize
2434 SetAlbumMovieWriteStreamDataSize

caps:u

This is "nn::capsrv::sf::IAlbumApplicationService".

This was added with [5.0.0+].

Cmd Name
32 [7.0.0+] #SetShimLibraryVersion
102 GetAlbumFileList0AafeAruidDeprecated
103 DeleteAlbumFileByAruid
104 GetAlbumFileSizeByAruid
105 DeleteAlbumFileByAruidForDebug
110 LoadAlbumScreenShotImageByAruid
120 LoadAlbumScreenShotThumbnailImageByAruid
130 PrecheckToCreateContentsByAruid
140 [6.0.0+] GetAlbumFileList1AafeAruidDeprecated
141 [6.0.0+] GetAlbumFileList2AafeUidAruidDeprecated
142 [7.0.0+] GetAlbumFileList3AaeAruid
143 [7.0.0+] GetAlbumFileList4AaeUidAruid
60002 OpenAccessorSessionForApplication

SetShimLibraryVersion

Takes an input u64 #ShimLibraryVersion, an u64 AppletResourceUserId, and a PID, no output.

IAlbumAccessorApplicationSession

This is "nn::capsrv::sf::IAlbumAccessorApplicationSession".

This was added with [5.0.0+].

Cmd Name
2001 OpenAlbumMovieReadStream
2002 CloseAlbumMovieReadStream
2003 GetAlbumMovieReadStreamMovieDataSize
2004 ReadMovieDataFromAlbumMovieReadStream
2005 GetAlbumMovieReadStreamBrokenReason

ShimLibraryVersion

This is a version field. Official sw uses func nn::capsrv::GetShimLibraryVersion() to load this from a global var, which is then used with various commands (the input for those cmds must match value 1).

[7.0.0-8.1.0] This is value 1.

Controls which struct version to use for #ApplicationAlbumEntry / #AlbumFileEntry. However, the struct size for the newer version is used regardless on [7.0.0+] for the actual cmds.

AlbumEntry

Offset Size Description
0x0 0x8 Unknown
0x8 0x8 titleID
0x10 0x2 Year
0x12 0x1 Month
0x13 0x1 Day
0x14 0x1 Hour
0x15 0x1 Minute
0x16 0x1 Second
0x17 0x1 Unknown
0x18 0x1 Unknown
0x19 0x1 Unknown
0x1A 0x6 Padding?

This is "nn::capsrv::AlbumEntry". This is a 0x20-byte struct.

The data at offset 0x10 size 0x8 corresponds to each field in the Album entry filename, prior to the "-".

AlbumFileEntry

This is "nn::album::AlbumFileEntry". This is identical to #ApplicationAlbumEntry. On older versions where official sw used to use cmds which use #ApplicationAlbumFileEntry, this struct matches #ApplicationAlbumFileEntry.

ApplicationAlbumEntry

Offset Size Description
0x0 0x20 Unknown.

This is "nn::capsrv::ApplicationAlbumEntry". This is a 0x20-byte struct. On older versions where #ShimLibraryVersion is 0, this has a different format.

With the output from caps:su sdk-nso only uses this for the Share-applet (when the output is used at all), with everything else it's used as an #AlbumFileEntry. In those cases with the nn::album wrapper funcs, it's "converted" by just copying the struct (arrays are "converted" by just returning a ptr to the input array).

ApplicationAlbumFileEntry

This is "nn::capsrv::ApplicationAlbumFileEntry". This is a 0x30-byte struct.

On newer versions where official sw uses #ApplicationAlbumEntry, #ApplicationAlbumEntry is converted to ApplicationAlbumFileEntry when using cmds which need it with:

  • First 0x20-bytes are the same.
  • u64 ApplicationAlbumFileEntry+0x20 = #ApplicationAlbumEntry+0x10.
  • Last 8-bytes = 0.

Notes

capsrv is responsible for validating the MACs for screenshots stored on the SD card, if the setting capsrv!enable_album_screenshot_filedata_verification is non-zero.

Screenshots are validated as follows: The JPEG's MAC is extracted from the EXIF maker note, and stored. A timestamp string is generated by calling snprintf(&str, 20, "%04d:%02d:%02d %02d:%02d:%02d", ...); with stored timestamp values. If this doesn't match the timestamp string stored in EXIF, then an error 0xA34CE is returned. Otherwise, the entire JPEG is loaded into memory, and the stored EXIF maker note is cleared to zeroes. Then, an HMAC-SHA256 is computed over the entire JPEG using a hardcoded secret key. if (memcmp(calculated_hmac, stored_hmac, 0x10) == 0), the screenshot is valid, else 0xA3ACE is returned.

In 3.0.0, MAC calculation was changed: now, instead of calculating an HMAC, a plain SHA256 hash is calculated. capsrv basically does screenshot_kek = spl::GenerateAesKek(<hardcoded screenshot_kek_source>); spl::LoadAesKey(screenshot_kek, <hardcoded screenshot_key_source>); MAC = spl::ComputeCmac(hash);

Videos

4.0.0 includes video playback etc support in Album via mp4. These include a JPEG thumbnail, which is used for video "validation". The EXIF is also much larger: the MakerNote is 0x498-bytes, with encrypted data starting at offset +0x8. This encryption uses AES-CTR with hardcoded key/ctr. MAC calculation works the same way as the 3.0.0+ JPEG MAC calculation, except with a different movie_kek_source/movie_key_source.

Note: the Album process itself uses libstagefright for video playback.

Retrieved from "https://switchbrew.org/w/index.php?title=Capture_services&oldid=7560"