poor_man_dropbox

Run the server:

DEBUG=1 ./server.py dir

Run the client:

DEBUG=1 ./client.py src_folder

If you want to run the server, and accept outside connection: export HOST=0.0.0.0

If you want the client to connect to remove host, use the same: export HOST=192.168.1.22

• simple binary format
• zlib on-the-fly compression
• path traversal protection
• duplicate file copying instead of re-transmission optimization
• delta based updated
• TLS encryption
• unit tests

Known issues: there has been some bugs witnessed in regards to moving folders (might be fixed now?)

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BINARY FORMAT

Endianness: Network order Every header starts with:

[<payload-size><request-type>]

payload size: 8 bytes, the entire size of the payload being sent, values : 0 to (2^64)-1

request type: 1 byte , the type of request being sent, values: F | C | D | M | X

'F' indicates *normal file upload*

'C' indicates *copy instruction*

'M' indicates a file or folder *move*

'D' indicates *delete instruction*

'X' indicates a new folder must be created

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A F request contains the following extra fields:

[<length-of-filepath><filepath><sha256>]

length-of-filepath: 4 bytes, value: length of the filepath

filepath: variable amount of bytes, determined from length-of-filepath, values: utf-8 encoded filepath

sha256: 32 bytes containing sha256 hash of file being upload

The remaining payload can be calculated by simply subtracting from the amount of header bytes recieved.

The reset of payload sent is:

[<length-of-cdata><cdata>]

length-of-cdata: length of zlib compressed payload, value: 0 to (2^32)-1 cdata: compressed data bytes

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A C request contains the following extra fields:

[<length-of-source-filepath><source-filepath><length-of-dst-filepath><dst-filepath>]

length-of-source-filepath: 4 bytes, value: length of source filepath

source-filepath: same as filepath described above

length-of-dest-filepath: 4 bytes, value: length of destination filepath

dst-filepath: same as filepath described above

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A M request is the same as a C request, as above, except the server moves a file.

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A D request contains the following extra fields:

[<length-of-filepath><filepath>]

length-of-filepath: 4 bytes, value: length of source filepath

filepath: same as filepath described above

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A X request is the same as a D request, as above, except the server creates an empty folder.