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Capability Representation

Linux implements capabilities as values ranging from 0 to 31. The particular range is chosen for the easier representation in a 32-bit bitmaps where each capability occupies one bit. As already existing capabilities occupy values up to 28, LinSec implementation had to enlarge the possible maximum capability value to 63. This implied a change of bitmap size for capability set representation from 32 to 64 bits. The alterations were carried out in linux/capability.h header file.