What is HMAC-SHA256 Gambling?
Key facts
- HMAC-SHA256 is the keyed-hash construction defined in RFC 2104 — collision-resistant, pre-image-resistant, and standardised since 1997.
- Once a server commits the SHA-256 of its seed before a round, it cannot retroactively change the seed without invalidating the commitment.
- Each game maps the 256-bit HMAC output to its specific outcome (a multiplier, a card index, a mine layout) via a documented, reproducible algorithm.
- On Rust Snowball, the mapping algorithms are published in the open-source @rustsnowball/provably-fair package — players can re-derive any historic result.
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Related
Frequently asked questions
- What is HMAC-SHA256 Gambling?
- HMAC-SHA256 gambling refers to provably-fair casino games that use the HMAC-SHA256 keyed-hash function to deterministically produce game outcomes from a committed server seed, a player-supplied client seed, and an incrementing nonce — the same inputs always produce the same outcome, so any past round can be independently re-verified.
- HMAC-SHA256 Gambling — fact 1?
- HMAC-SHA256 is the keyed-hash construction defined in RFC 2104 — collision-resistant, pre-image-resistant, and standardised since 1997.
- HMAC-SHA256 Gambling — fact 2?
- Once a server commits the SHA-256 of its seed before a round, it cannot retroactively change the seed without invalidating the commitment.
- HMAC-SHA256 Gambling — fact 3?
- Each game maps the 256-bit HMAC output to its specific outcome (a multiplier, a card index, a mine layout) via a documented, reproducible algorithm.
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