Return errors for undersize decode buffers and trailing whitespace #163
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The length calculations we presently perform are dependent on whitespace-free inputs. This adds an (unfortunately non-constant time) check that the *last* character is *NOT* whitespace. Ideally this would be replaced with a constant time "trim" function that can slice away leading/trailing whitespace, but for now this gives a meaningful error. It also adds checks that buffers are correctly sized to receive the resulting output, where otherwise it would've panicked for an undersize buffer. This is a potential DoS vector if subtle-encoding was used on untrusted inputs.
tarcieri
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subtle-encoding/length-and-whitespace-handling-fixes
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The length calculations we presently perform are dependent on whitespace-free inputs.
This adds an (unfortunately non-constant time) check that the last character is NOT whitespace. Ideally this would be replaced with a constant time "trim" function that can slice away leading/trailing
whitespace, but for now this gives a meaningful error.
It also adds checks that buffers are correctly sized to receive the resulting output, where otherwise it would've panicked for an undersize buffer. This is a potential DoS vector if subtle-encoding was used on untrusted inputs.