crypto: fix large DH generator validation#64092
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Unfortunately, `std::optional<>` implements `operator<` in such a way that this check will fail for very large generators. Since `bn_g` is unsigned, if its value does not fit into a single word, we can be certain that it is at least 2. By only checking the value if it does indeed fit into a word, the check correctly ignores very large generators. Signed-off-by: Tobias Nießen <tniessen@tnie.de>
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panva
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Jun 23, 2026
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Unfortunately,
std::optional<>implementsoperator<in such a way that this check will fail for very large generators. Sincebn_gis unsigned, if its value does not fit into a single word, we can be certain that it is at least 2. By only checking the value if it does indeed fit into a word, the check correctly ignores very large generators.