Keccak256

The OpenVM Keccak256 guest library (openvm-keccak256) provides access to an accelerated Keccak-256 hash function.

The library provides:

keccak256(input: &[u8]) -> [u8; 32]: Computes the Keccak-256 hash of the input data and returns it as an array of 32 bytes.
set_keccak256(input: &[u8], output: &mut [u8; 32]): Computes the Keccak-256 hash of the input data into the provided output buffer.
Keccak256 struct: Implements the tiny_keccak::Hasher trait for incremental hashing via update and finalize methods.

The Keccak256 struct can be used to incrementally hash a stream of bytes:

fn update(&mut self, data: &[u8]);
fn finalize(self, output: &mut [u8]);

See the full example here.

Example

The following example can be run as guest code or host code (i.e. run in the zkvm or natively). To run with guest code, use cargo openvm run, and for host code use cargo run. The implementation for Keccak256 falls back to using tiny_keccak when running as host code.

use hex_literal::hex;
#[cfg(target_os = "zkvm")]
use openvm as _;
use tiny_keccak::{Hasher, Keccak};
 
/// Vector of test cases for Keccak-256 hash function.
/// Each test case consists of (input_bytes, expected_hash_result).
const KECCAK_TEST_CASES: &[(&[u8], [u8; 32])] = &[
    (
        b"",
        hex!("c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470"),
    ),
    (
        b"hello world",
        hex!("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad"),
    ),
    (
        &hex!("91376f5774419e518ced240cfb7ce0fbb835d80c609f7db3736a8474381c23cb7dde504e009f8d9656351a22ff18172046cbd80e074ee99ac7cc95f0daf32c35d4a0b41932d6efee42790e0298fa3d8f0d362f79008e9bd9989b355470e714aebd0d5936bbbfcc11d4"),
        hex!("bcd603061b992b3c881b2418a691c4a77606f4e9ff4fb1e57bd64118430f9e64"),
    ),
    (
        &hex!("2e8b467f65bb7a367e17b0f1ea54e20cfcd5f581bb7a9e937b1d48e289cb8477a4aa081031666529e3659782945bdadc3524e069b1e50da71caa04e681e986869325ba36e2fd"),
        hex!("f5856263b398ac1b9682363fd87f3f47d96c213d9a27ca84f42ccdc69c04b600"),
    ),
    (
        &hex!("8c7e1ae8d32e176dbb4c25dfbfa4edf2c642"),
        hex!("1d673221b76ffb970ef7abec781e7e8678ef7535b95ffc9dd7e7b9ebb472e155"),
    ),
    (
        &hex!("1f483a587db0a0152083be135d4418a3387a9d223a3329b8044ac6b97dfb754718cec558ab6cf6fb0f46b344442326b7d639ec7b81e0eac95340bb3e96860368961a82d98f35eb893dd848da52e7a7cc3d970657592071da1ea70ce99c995d2bdf4f9f764f2ca277705843f0800e7a97"),
        hex!("b83494263c50b8444ae444d436ed9a30065ce869342d9c3a5fe319ed323b3ac6"),
    ),
    (
        &hex!("a2d386e126c7"),
        hex!("d94338cbf5a5505c6079f381bc9c5f895a93911ea906d84ccf1c876ae24f31f9"),
    ),
    (
        &hex!("590307764a0f2294f82301735054adc163cd1ee5c582fc3d173f54ba7c5f6dbe72aa30ce8007657d7bafb9d083e80574b3d3a69469ed43cf61cdd8bb2d2762a0861affae378c052dad637707f420cfbc1dbbf7"),
        hex!("03c2229015d2693d8448b1761c04ae80cee6e11e046ae2d3ebeb4291531abf8d"),
    ),
    (
        &hex!("8b0d83e9b5d1770faa1f17195a9c8fa74bd5109e50ba74f752d1a40189b0f2d7dd8abe3b0c9648f67f413f584ccea0f69fa2346460dd97a28acb1d0ba8618398817c76be800cebce0d701595ac0b5f422775c504"),
        hex!("3390695701398af69128d9d8fc4a8a1c43c340e65b673a896dd40360c4c816f9"),
    ),
    (
        &hex!("2f80c45d979eb3f7"),
        hex!("12292d148143f86721726f656ae496b95d113dd669f78e202ac2cca9bca8304c"),
    ),
    (
        &hex!("d43a4df4bf208321971cabff80d9ae2bf619bfac98004b729e6415a481bf70089a39ad5019f21d4bec3dd8f2598cf9fccc6a5fcd5ac79d516d1fdbb123b4bda96021130b44fde0633c50ae85c376db29b551edb16d5fac451b0cbea06356f80661b011f3904e3c62ea9f8ad3773da5"),
        hex!("1cf0c4b5afb89f146d9b09d878d4afc00aa8a56037ff8602071ce989f3e58695"),
    ),
    (
        &hex!("72ba3368324d809df9a9d97e251e00a6dfb3e70fca2892e63ee3df6d5b08e01e63c9db23296586bf9a3ee78a68"),
        hex!("7d79f8ed4fb4cd728d9ca383536f81f025d8e246504f5e9d53cbfa05006abad1"),
    ),
    (
        &hex!("6b0bd4f931c1d8861f5ccea87642791dfa74fe8544175fb63451ee0adcfcc13f3040ab8f7525892fcd7da15ce23da3b2f21a6e55dca0765daeb2407acff87c03b7d1a13d3acd77390d6055fde3eeeeef381c04cd41d5c83bd3ef7e494a8391de3a6d8f1f1941e9fb217bd8"),
        hex!("9550d5094b85b0d1f01209b71c338114a09aad20cb33b7d444c31c1e1473716b"),
    ),
    (
        &hex!("494c7a2642a3d6b3943605cbc30140aaf622f3a34338fdff183e5ef6bc41389d6f095056760dd144f0a14a2b21ca5b487cab0a3ea23a86"),
        hex!("a03c900c3ebf6c4037f8351b1a144720a04a105e067707c5cbac79aade25fb56"),
    ),
    (
        &hex!("4d91a527e6bd5ea378c5ba9516b8b34cc99dd7c52ed03b54623f1ce4ca6d886b37c95dde605fb7ab8274f21488229bd9169e760703747ae9d23699f77db579f1ad31ef8dbdb57cce0de326db8bbc6550a5cc5fe09c8486ef24ef023b4f2f8aa32e390ede54eb3d6123fbc08a8e591d6cad80c3fe52821da10136cce9"),
        hex!("5b47a38b57bfe74950e59da3c1918d94293d4250b8991a3324ec42160b3d402c"),
    ),
    (
        &hex!("9e60df2407f3057680e332f32cafb32e195aa13c275c1571c4877da2f26b00ed139f808310e9e4a800fd950ddbb3dc"),
        hex!("52474f4d926fa0599845e38ab4a9529737bd42f0d46784d5f584c7ab063c18f7"),
    ),
    (
        &hex!("712b9a6afe96f461e31092ffe38d74288cb1424e876a3592bca03dbc9c3a57"),
        hex!("3b0a1d9106e06e1a3de754fc90583862e82ec92f81edf261e5a12108d46a69bf"),
    ),
    (
        &hex!("9feff865dad6dc06e095d330f363178b71e56fd1b86fcac2249aed2a84a82fa4d596d6f4142b71ec034f543d69bdbc47404b8146203b215ce3bce1a8c4"),
        hex!("63fe4b8bd1e0d823b5d7b6ab722c5b5dfcfe472da792e8974a38cc81fdd53777"),
    ),
    (
        &hex!("0213643f8bbb0aa1e9528f7f117c050cbd9d8709cc3672850363c0ddef5be2001c"),
        hex!("4bf5a88bb8954c539620033214e1b1e34306639417c7b7683a4aa825f5c004bb"),
    ),
    (
        &hex!("a79eca9f55b0f13c533ca91e71495f65f642ab91224bbe664ff59b1b3362ba51"),
        hex!("a710b4cbdc60423e7ab1773d6731ceb3ea0157cff6df39a1b8c1410acf8c0075"),
    ),
    (
        &hex!("4cc8abc63b48a1a653c3a52801394db7ae608249d67006329fd259ec203a1ed836f384ed88b6dff310948c9f29f7c240fc49d705299e8aec3239e35c998c2befbd8997e59c8581"),
        hex!("ba972e77578147700ba7539b89e53fc40bdd9893b3cccef0bcf1a2f7ef65c4bc"),
    ),
    (
        &hex!("f66cd0cd9a55d6c2046dd7df0cf6496a876d165d0de8f639140cafa2155abc2426cc55258e0db47938d262472558f4eb63e98cfd3725296dc1de7c57d9d148194c2ac3b9d0c267814578bfc66c46da093bc59f132b41076865659d548ed3"),
        hex!("54ea328ab976e794e653b82d5cfbc0f20305e6e33a97bf4e8764d06bbed2753c"),
    ),
    (
        &hex!("fe7eee2bcc4071ab2bcd801d805cc082bc0d7781713941e06e4819e09748a5692c945f3b3b0b632b50bce1"),
        hex!("57a655827352ff95ce21082515add7f6fb0f51b457e338a1cfd7a5912a2c30a0"),
    ),
    (
        &hex!("2cf005de4865b6321e8995f38825353e64e34f7ecaedd9b5f39ee41067e9e63f38618985d015b1fb89be1140e249ac92d0b8f273"),
        hex!("0ba80a1c481facdec27552c2d8382467fb97f864a6c915e2882045a995dd452a"),
    ),
    (
        &hex!("edee326b959740e515dd8a0ed9ced665d782b50bda2af634189def905b59d3a9ac635e1d96c670eaf28675b0071db0d86131088fad00a0b80da10dd1259692d17dc9af43a5e3f40185e88776be68bdf2a3ddeb7c9726e5bde8e4d14bcf6e991d142047"),
        hex!("295d1a5a86a4ea5cc3d7c5860c3fa6069374a610e5f9cda1e643b4f01e957752"),
    ),
    (
        &hex!("8703f576434a9ec235904e106991aa447b1d4e715fd1fe2e5aa2e3aa950291d624d97420dc9eec10d76cdf23ae189c995760f339c20bbb5e"),
        hex!("7ebb76c5e9669e9bceb867560682a653e600e116af83777ed6e71fb4b28f1b48"),
    ),
    (
        &hex!("e8dffb080d61e60561a5f2e44db8e65c4ab134f3283411b374da96cc6a94408871de72d5b8e39aae83c81fa7b31027a8da64915010eb688a72f5f605aab2b77d67baa1f90056281e92fa3031108e2061a1b110f4d0d62ff91f956f977cc504a68337d7b01d2ff6caadc57e"),
        hex!("e85f50155c3abf4d0cabe2a62d9af075c163600fb0c12e1bc3d004ce4d25bd13"),
    ),
    (
        &hex!("5de9ef34a6f71cbe1780ff29816f7b26f574f0ea5d6adeaff6d9c78e08440ce9c3a5597e31693e0d2a89b1b84bf3b8c8cda9c13b7abb3bf8b2cf0cb3410d9df1e6fd4765546ce8f4e1d821aa7253fdf044437a65eca5d7393716"),
        hex!("3de18f83084b4ced8b0a261f80225b52cf9c27950dff768bb2e0ab1a8f015fe2"),
    ),
    (
        &hex!("8278f74015c08ea408c53446d4e9364eddc6c37cf2a03b54df9a9122095eef5f3812d03afa4f7c52ba937f73968e3074ed5ddd7a6439916b8c4a6bb821896852bbe1430be00f9da2244d980834696f949232facdc0e214f52f308267"),
        hex!("1f60d8c4bfd1cf910fd7e5a5ecd3e2996aee20d7c40c1f6d43225d832b937b0a"),
    ),
    (
        &hex!("65063a451690b64af8901e2cc0414abbe0e92c6789c721577bf975b4cd58771086ad8f6e2899bf45e7f23e76a299accae8782dd1f47fa449d7cc7f06ced46bd7bde7ce5f61e594485a6489edd5dc96ad79c5425960297b028f9669fb827a"),
        hex!("30d3360dbb001c115a287da3eac988b1a925b2ab607ba1e1f909a64eef1c90e4"),
    ),
    (
        &hex!("41c7813c97"),
        hex!("be714f64489c82a8fc1008db96c096bd72b74ca142f8682c19aa5d7b8d575d31"),
    ),
    (
        &hex!("7a9fa65269a9af8e994849b91c58c9ad2b4da115a96514a02200d931c359e4a26ff54c3937ed061a1e58e7cf2c1b1dd72c42049081fe28dd59caaf09447c403c167265d5e121e367d41fc87c3c1c9a81c582ee826cfe"),
        hex!("41ca49571619a8b82cd7bff0e317493eb70d8dfaee994702c3c1ad80b794c863"),
    ),
    (
        &hex!("d8b70735a52277d4e361a68b884abf5118756c5685dd0af29e8274b94ab37bc126dbb8e97735cf"),
        hex!("a43a2a0321aac66ed239bc40518f9947ae4480bc70d4b1c23bbe5d1a367e1cd1"),
    ),
    (
        &hex!("190dcb4311e6c20f303e939bea29a0f42856735821743d92579d1d2e41b0925304e08be11e978aa760993083bf546a31d8e1877b405f14f3bdcae789ed5d639e51ac846ab2390ae9552e733a7233"),
        hex!("f5392ee04880a0bd1336f30ee79b5c014a90728bf29f422dabb4ae6bc972f30b"),
    ),
];
pub fn main() {
    // Run the keccak tests for all targets
    for &(input, expected) in KECCAK_TEST_CASES {
        let mut output = [0u8; 32];
 
        // Using tiny-keccak API
        let mut hasher = Keccak::v256();
        hasher.update(input);
        hasher.finalize(&mut output);
 
        assert_eq!(output, expected);
    }
 
    println!(
        "All {} keccak256 test cases passed!",
        KECCAK_TEST_CASES.len()
    );
}

To be able to import the keccak256 function, add the following to your Cargo.toml file:

openvm-keccak256 = { git = "https://github.com/openvm-org/openvm.git", tag = "v2.0.0-beta.2" }

Alternatively, you can use tiny-keccak directly, as shown in the example. When compiled for the zkVM target, tiny-keccak automatically routes through the accelerated OpenVM Keccak256 extension; when running natively, it falls back to a pure software implementation. To use tiny-keccak, add the following to your Cargo.toml:

tiny-keccak = { git = "https://github.com/openvm-org/tiny-keccak", features = ["keccak"] }

Config parameters

For the guest program to build successfully add the following to your .toml file:

[app_vm_config.keccak]