trezor-firmware/docs/core/misc/translations.md

Translations blob format

offset	length	name	description	hash
0x0000	6	magic	blob magic TRTR00
0x0006	2	container_len	total length (up to padding)
0x0008	2	header_len	header length
0x000A	2	header_magic	header magic TR
0x000C	8	language_tag	BCP 47 language tag (e.g. cs-CZ, en-US, ...)	header
0x0014	4	version	4 bytes of version (major, minor, patch, build)	header
0x0018	2	data_len	length of the raw data, i.e. translations + fonts	header
0x001A	32	data_hash	SHA-256 hash of the data	header
0x003A	header_len - 48	ignored	reserved for forward compatibility	header
?	2	proof_len	length of merkle proof and signature in bytes
?	1	proof_count	number of merkle proof items following
?	proof_count * 20	proof	array of sha256 hashes
?	1	sig_mask	CoSi signature mask
?	64	sig	ed25519 CoSi signature of merkle root
?	2	translations_len	length of the translated strings	data
?	translations_len	translations	translated string data	data
?	2	fonts_len	length of the font data	data
?	fonts_len	fonts	font data	data
?	?	padding	0xff bytes padding to flash sector boundary

Translation data

Offsets refer to the strings field, up to the following offset. First offset is always 0, following offset must always be equal or greater (equal denotes empty string).

offset	length	name	description
0x0000	2	count	number of offsets, excluding the sentinel
0x0002	2	offset[0]	offset of string id 0 in the strings field
...	2	...
?	2	offset[count - 1]	offset of string id count - 1 in the strings field
?	2	offset[count]	offset past the last element
?	translations_len - 2 * (count + 2)	strings	concatenation of UTF-8 strings

Fonts

Ids must be in increasing order, offsets must be in non-decreasing order. First offset must be 0.

offset	length	name	description
0x0000	2	count	number of items in the offset table, excluding the sentinel
0x0002	2	id[0]	numeric id of the first font
0x0004	2	offset[0]	offset of the first font in the fonts field
...	...	...
?	?	id[count - 1]	numeric id of the last font
?	?	offset[count - 1]	offset of the last font in the fonts field
?	?	sentinel_id	sentinel 0xffff
?	?	sentinel_offset	offset past the end of last element
	?	fonts	concatenation of fonts, format defined in the next section
?	0-3	padding	padding (any value) for alignment purposes

Font data

The format is exactly the same as the previous table, the only difference is the interpretation of the payload.

offset	length	name	description
0x0000	2	count	number of items in the offset table, excluding the sentinel
0x0002	2	id[0]	id (Unicode code point) of the first glyph
0x0004	2	offset[0]	offset of the first glyph in the glyphs field
...	...	...
?	?	id[count - 1]	id (Unicode code point) of the last glyph
?	?	offset[count - 1]	offset of the last glyph in the glyphs field
?	?	sentinel_id	sentinel 0xffff
?	?	sentinel_offset	offset past the end of last element
	?	glyphs	concatenation of glyph bitmaps
?	0-3	padding	padding (any value) for alignment purposes