Mika Protocol Spec

Requset

iv is random bytes generated by client.
Key used to encrypt data is gengerated by the first part of password.
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|   iv  | req data |
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| Fixed | Variable |
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First block of req data (at least 23 bytes):
Chunk id is a unix time when requst was going to be sent. Server must verify chunk id.
Protocol claims how to resolve user data.
Hmac use sha1 as hash func, [iv]+[key] as key, and request header expect hmac as message.
hmac = Hmac(sha1, [iv]+[key], [header])
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| ver | cmd | reverse | protocol | protocol related | chunck id | hmac |
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|  1  |  1  |    2    |    1     |      Variable    |    8      | 10   |
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ver: 0x01

cmd:
data forward 0x01
server control 0x02

reverse: 0x0000

protocols:
TCP data forward(0x01)
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| atype | address  | port |
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|   1   | Variable |   2  |
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HTTP data forward(0x02)
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| protocol related |
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|        0         |
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UDP data forward(0x03)
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| atype |  address | port |
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|   1   | Variable |   2  |
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admin(0x05)

Other chunks of req data (at least 12 bytes):
Chunk id should increase one after a chunk was sent/recevied successfully. 
Server and client should hold same chunk id for the same chunk.
Hmac use sha1 as hach func, [iv]+[chunk id] as key, and [user data] as message.
hmac = Hmac(sha1, [iv]+[chunk id], [user data])
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| dataLen | hmac | user data |
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|   2     | 10   | Variable  |
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Response

iv is same as request.
Key used to encrypt data is gengerated by the last part of password.
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| resp data |
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|  Variable |
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