YouTube

The YouTube application available from the eShop is a web-browser. Like the main browser this uses WebKit. All data is downloaded with plaintext HTTP (3DS application).

The OSS for the 3DS / Wii U YouTube application is available at the following:

[1]
[2]

User-Agent and Browser Versions

The user-agent format is almost identical to the main browser: "Mozilla/5.0 (Nintendo 3DS; U; ; Factory Media Production) Version/<version>.<region>". <lang> is "en", "fr", etc. <region> is "US", "EU", etc. See below for <version>.

Browser version	USA/EUR CDN Title-version	Release date	Notes
1.7498	v16 and v0		Initial app version.
1.7498	v1056 and v1040		First app update. This build uses the v7.0 NCCH encryption for the main CXI, this was the first retail title to use this.
1.7498	v2096 and v2080	October 15, 2015	This update fixed the vuln used for tubehax. This version was built with the latest CTRSDK, so NATIVE_FIRM 9.6.0-X is now required. Plaintext HTTP is still used. The RomFS is empty, and accessinfo is still 0x0. Strings related to RO are still in the codebin, but during application startup ldr:ro isn't used at all. The CROs are now built with the main codebin(included with the main .text etc), hence the much larger sections listed below. The codebin sections are much larger: "Code text size: 0x003A9CF0" -> "Code text size: 0x00A81470" "Code ro size: 0x000B9360" -> "Code ro size: 0x0014C848" "Code data size: 0x00203F08" -> "Code data size: 0x00207788" "Code bss size: 0x00095748" -> "Code bss size: 0x00094F48" The USA codebin contains the following user-agent strings: "Mozilla/5.0 (Nintendo 3DS; U; Factory Media Production; en) Version/1.7498.US" and "Mozilla/5.0 (Nintendo 3DS New3DS; U; Factory Media Production; en) Version/1.7499.US". None of the public Old3DS/New3DS browserhax which were public at the time this YouTube app was updated, affect the YouTube app at all (no crashes). The "range" html <input> no longer displays: the page background-color is displayed where the slider would have been. Hence, unless there's a way to get this to actually display, sliderhax isn't usable with this YouTube app version. See here for the WebKit changes. The only actual code changes (in this commit) besides an optimization changeset being integrated, is changes for fixing the vuln used by tubehax. Originally the YouTube app used the DNS server from the system configuration. Now it's hard-coded to use Google's DNS server at IP address 8.8.8.8 via DNS-resolver socket code in the app itself (it's unknown whether this resolver code existed in the app before this version).

Updates for this application are forced, since the app itself checks for a newer version of the title (this is done before any actual HTTP requests by the actual application are done). This is done with Friend Services: the application tries to authenticate itself with FRDU. When the installed version is outdated, it gets an error-code in the output buffer for FRDU:GetGameAuthenticationData (this error-code then gets passed to the error-display applet). This is exactly what official games do when initializing online multiplayer too.

The friend HTTP requests which are involved with the above use HTTPS, so blocking it isn't an option (the usual POST request(s) to https://nasc.nintendowifi.net/ac): blocking it via DNS only results in a different error-code.

RomFS

The RomFS only contains CROs ("/cro/") and the CRR ("/.crr/static.crr"), the following is the "/cro/" contents:

JavaScriptCore_CTR.cro
WebCore_CTR.cro
WebkitMediaPlayer_CTR.cro
WebKit_CTR.cro
static.crs

3rd Party Libs

The youtube application seems to use libcurl, libjpeg, OpenSSL and ffmpeg.

Webkit

Looks like the YouTube application uses a newer version of Webkit than the Internet Browser applet. It has the ability to construct Blobs, of course the HTML5 video element, and possibly the Audio element (Visible, but untested). It also supports the localStorage API. Here a list of exposed apis: [3].

embedded.ctr

Inside the YouTube app, there is a pseudo-webserver running that links to a structure inside ExeFS. This structure provides a list of urls under the domain "http://embeded.ctr/".