38 lines
1.0 KiB
Ruby
38 lines
1.0 KiB
Ruby
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module EventMachine
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module WebSocket
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class MaskedString < String
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# Read a 4 bit XOR mask - further requested bytes will be unmasked
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def read_mask
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if respond_to?(:encoding) && encoding.name != "ASCII-8BIT"
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raise "MaskedString only operates on BINARY strings"
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end
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raise "Too short" if bytesize < 4 # TODO - change
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@masking_key = String.new(self[0..3])
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end
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# Removes the mask, behaves like a normal string again
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def unset_mask
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@masking_key = nil
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end
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def getbyte(index)
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if defined?(@masking_key) && @masking_key
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masked_char = super
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masked_char ? masked_char ^ @masking_key.getbyte(index % 4) : nil
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else
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super
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end
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end
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def getbytes(start_index, count)
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data = ''
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data.force_encoding('ASCII-8BIT') if data.respond_to?(:force_encoding)
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count.times do |i|
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data << getbyte(start_index + i)
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end
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data
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end
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end
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end
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end
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