WebFonts WG discussions

Hello all,

Last week, the discussion about using same-origin restriction and CORS (and the issues related to this approach) have been discussed on the WG mailing list (see [1] and other relevant messages in this thread), which prompted John Hudson to provide an excellent summary [2] of the benefits of the new web font format and the importance of the metadata that may be included in this new font wrapper.

I also noted that there is currently no mechanism supported by the WOFF format that would allow user agents to validate the integrity of the WOFF data and its font payload. I suggested to add a simple checksum the WOFF Header that would be calculated using data included in WOFF wrapper, taking into account the value of 'checkSumAdjustment' of the original font file encapsulated within WOFF file. This approach would allow user agents to verify the integrity of WOFF data fields and match it against the font 'checkSumAdjustment' encoded as part of the font 'head' table [3]. The suggested approach would *not* require decompressing the whole font to calculate checksum, and  would preserve the ability of UA to selectively decompress font tables to only retrieve portions of font data as needed.

WebFonts WG will discuss this and other issues during its first conference call on Wednesday this week. Your comments and considerations would be very welcome and much appreciated.

Thank you,
Vladimir

[1] http://lists.w3.org/Archives/Public/public-webfonts-wg/2010Apr/0061.html
[2] http://lists.w3.org/Archives/Public/public-webfonts-wg/2010Apr/0062.html
[3] http://lists.w3.org/Archives/Public/public-webfonts-wg/2010Apr/0065.html