NuFW reference manual
PrevChapter 4. Modules configuration 

4.12. mark flag

4.12.1. nuauth_flag_nbits

Number of bits to overwrite in the mark.

Default: mark_flag_nbits=16

4.12.2. nuauth_flag_mark_shift

Position of the overwritten part of the mark (in bits).

Default: mark_flag_mark_shift=16

4.12.3. nuauth_flag_flag_shift

Position in the flag of the bytes use to overwrite the mark (in bits).

Default: mark_flag_flag_shift=16

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