53 lines
1.1 KiB
C
53 lines
1.1 KiB
C
#ifndef _IPXE_NULL_ENTROPY_H
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#define _IPXE_NULL_ENTROPY_H
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/** @file
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*
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* Nonexistent entropy source
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*
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* This source provides no entropy and must NOT be used in a
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* security-sensitive environment.
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*/
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FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
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#include <stdint.h>
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#ifdef ENTROPY_NULL
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#define ENTROPY_PREFIX_null
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#else
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#define ENTROPY_PREFIX_null __null_
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#endif
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static inline __always_inline int
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ENTROPY_INLINE ( null, entropy_enable ) ( void ) {
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/* Do nothing */
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return 0;
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}
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static inline __always_inline void
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ENTROPY_INLINE ( null, entropy_disable ) ( void ) {
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/* Do nothing */
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}
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static inline __always_inline double
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ENTROPY_INLINE ( null, min_entropy_per_sample ) ( void ) {
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/* Actual amount of min-entropy is zero. To avoid
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* division-by-zero errors and to allow compilation of
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* entropy-consuming code, pretend to have 1 bit of entropy in
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* each sample.
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*/
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return 1.0;
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}
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static inline __always_inline int
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ENTROPY_INLINE ( null, get_noise ) ( noise_sample_t *noise ) {
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/* All sample values are constant */
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*noise = 0x01;
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return 0;
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}
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#endif /* _IPXE_NULL_ENTROPY_H */
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