Doublespeak: Protocol Specification

	B	C	D	E	F	G	H	I	J	K	L
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2	Protocol signature	Protocol version	Checksum	Data type	Data length	Data
3	1 byte	1 byte	4 bytes	1 byte	Variable length quantity	Length based on data length field
4	ASCII letter "D"	Currently 0 (zero)	CRC-32 calculated on decoded data field	1st bit: Compression 0: Encryption wrapper 1: Text 2: File	Variable length quantity representing length of the data field in bytes Needed to allow decoding of multiple concatenated messages	Depends on data type
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6	⁢⁢‌‌⁣︁⁠⁯⁡⁫⁫‌‌‍‍⁣⁢⁤⁫⁤⁬⁪⁡⁠‌⁪⁪⁤⁪⁠⁤⁮⁪⁡⁠‌⁤⁬⁤︁⁠‌⁪⁡⁪‌⁪⁠⁤⁣⁤‍⁤⁢⁪⁡⁤⁫⁤⁣⁤⁣⁪⁢⁪⁡⁠‌⁪⁢⁤⁤⁠︁					Text
7						Text
8						Remaining length
9						UTF-8 encoded
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11						File
12						MIME type	File name	File
13						Variable length (null terminated)	Variable length (null terminated)	Remaining length
14						Is best-effort on the part of the transmitting client	May contain characters illegal on some platforms In the event that a receiving client cannot save the file to disk as named, the client must transform illegal characters	Binary blob
15
16						Encryption wrapper	Assume AES-GCM 128-bit, PBKDF2
17						Options length	Options	Salt	Ciphertext
18						Variable length quantity	Length based on options length field	16 bytes	Remaining length
19						Can be 0 (zero)	Used for storing IVs, nonces, etc.	Generated using a cryptographically secure PRNG	Binary blob
20
21									Ciphertext
22									Data type	Padding length	Data
23									1 byte	1 byte	Remaining length
24									1st bit: Compression 1: Text 2: File	Only present when block cipher is used	Depends on data type
25
26	Decimal	Hex	Binary	Character	Description
27	0	0	0000	U+200C	zero-width non-joiner
28	1	1	0001	U+200D	zero-width joiner
29	2	2	0010	U+2060	word joiner
30	3	3	0011	U+2061	function application
31	4	4	0100	U+2062	invisible times
32	5	5	0101	U+2063	invisible separator
33	6	6	0110	U+2064	invisible plus
34	7	7	0111	U+206A	inhibit symmetric swapping
35	8	8	1000	U+206B	activate symmetric swapping
36	9	9	1001	U+206C	inhibit Arabic form shaping
37	10	A	1010	U+206D	activate Arabic form shaping
38	11	B	1011	U+206E	national digit shapes
39	12	C	1100	U+206F	nominal digit shapes
40	13	D	1101	U+FE00	variation selector-1
41	14	E	1110	U+FE01	variation selector-2
42	15	F	1111	U+FEFF	zero-width non-breaking space
43	https://invisible-characters.com/
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