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34 lines
935 B
Markdown
34 lines
935 B
Markdown
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# Notes on http parser corner cases
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## Dealing with %00
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%00 is considered illegal in
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- the path part of the URL. A lot of user code handles it as a NUL terminated string,
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even though the header get apis are based around length. So it is disallowed to
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avoid ambiguity.
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- the name part of a urlarg, like ?name=value
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%00 is valid in
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- the value part of a urlarg, like ?name=value
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When the parser sees %00 where it is not allowed, it simply drops the connection.
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## Note on proper urlarg handling
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urlargs are allowed to contain non-NUL terminated binary. So it is important to
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use the length-based urlarg apis
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- `lws_hdr_copy_fragment()`
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- `lws_get_urlarg_by_name_safe()`
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The non-length based urlarg api
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- `lws_get_urlarg_by_name()`
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...is soft-deprecated, it's still allowed but it will be fooled by the first %00
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seen in the argument into truncating the argument. Use `lws_get_urlarg_by_name_safe()`
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instead.
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