Embed System Fonts on Android

.gitattributes

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-*.zip binary
+*.zip binary
+*.ttf binary
+*.otf binary
+*.ttc binary

build/components/README.md

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+## Components on Cromite
+
+Cromite needs to download certain static files for certain features.
+Specifically, the need arises from making the fonts used by the browser standard, in order to minimise the use of fingerprint scripts based on the fonts present on the device.
+
+To do this, the automatic update of components was reactivated with some differences compared to Chromium:
+
+- Since there is no backend, the response to the request for updates is static (see `query.json`). It currently resides on the cromite.org site because, deliberately, no request log is active.
+- The update file (a zip file) is downloaded only once and, if already done, nothing more is requested externally, unless the user goes to `chrome://components` and requests the update check.
+
+It is possible to generate a zip for the components in this way:
+
+### prerequisites
+
+- generate a der file, used to 'sign' the zip:
+
+```
+openssl genrsa 4096 | openssl pkcs8 \
+   -inform PEM -nocrypt -topk8 -outform DER \
+   -out cromite.pkcs8.der
+```
+
+currently the certificate used for cromite is in the pkcs8.der.asc, encrypted with gpg, so not public, for security reasons.
+
+- build `crx3_build_action`, necessary for 'signing' the zip:
+
+```
+ninja -C out/lin64 crx3_build_action
+```
+
+### how to generate the zip
+
+simply:
+
+```
+zip -j fonts.zip fonts/*
+out/lin64/crx3_build_action fonts_component.zip fonts.zip pkcs8.der
+```
+
+the resulting zip cannot currently be unzipped with system tools.
+
+The zip must contain the file `manifest.json`.
+
+### important sections in the query.json
+
+- `appid`:
+is the value used to identify the component. currently I do not know how to create a new one, there is no documentation or code to generate it.
+- `codebase`:
+is the base url from which to download the file
+- `name`:
+is the name of the file to download, the url is "codebase + name"
+- `hash_sha256`:
+is the hash of the resulting zip, used for comparison. compatible with sha256sum
+- `fp`:
+currently not used, is an additional protection mechanism for which I have found no documentation.