openvm_stark_sdk/config/
baby_bear_bytehash.rs

1use std::sync::Arc;
2
3use openvm_stark_backend::{
4    config::StarkConfig,
5    interaction::fri_log_up::FriLogUpPhase,
6    p3_challenger::{HashChallenger, SerializingChallenger32},
7    p3_commit::ExtensionMmcs,
8    p3_field::extension::BinomialExtensionField,
9    prover::{
10        cpu::{CpuBackend, CpuDevice},
11        MultiTraceStarkProver,
12    },
13};
14use p3_baby_bear::BabyBear;
15use p3_dft::Radix2DitParallel;
16use p3_fri::{FriParameters as P3FriParameters, TwoAdicFriPcs};
17use p3_merkle_tree::MerkleTreeMmcs;
18use p3_symmetric::{CompressionFunctionFromHasher, CryptographicHasher, SerializingHasher};
19
20use super::FriParameters;
21use crate::{
22    config::fri_params::SecurityParameters,
23    engine::{StarkEngine, StarkFriEngine},
24};
25
26type Val = BabyBear;
27type Challenge = BinomialExtensionField<Val, 4>;
28
29// Generic over H: CryptographicHasher<u8, [u8; 32]>
30type FieldHash<H> = SerializingHasher<H>;
31type Compress<H> = CompressionFunctionFromHasher<H, 2, 32>;
32// type InstrCompress<H> = Instrumented<Compress<H>>;
33
34type ValMmcs<H> = MerkleTreeMmcs<Val, u8, FieldHash<H>, Compress<H>, 32>;
35type ChallengeMmcs<H> = ExtensionMmcs<Val, Challenge, ValMmcs<H>>;
36type Dft = Radix2DitParallel<Val>;
37type Challenger<H> = SerializingChallenger32<Val, HashChallenger<u8, H, 32>>;
38
39type Pcs<H> = TwoAdicFriPcs<Val, Dft, ValMmcs<H>, ChallengeMmcs<H>>;
40
41type RapPhase<H> = FriLogUpPhase<Val, Challenge, Challenger<H>>;
42
43pub type BabyBearByteHashConfig<H> = StarkConfig<Pcs<H>, RapPhase<H>, Challenge, Challenger<H>>;
44
45pub struct BabyBearByteHashEngine<H>
46where
47    H: CryptographicHasher<u8, [u8; 32]> + Clone,
48{
49    pub fri_params: FriParameters,
50    pub device: CpuDevice<BabyBearByteHashConfig<H>>,
51    pub byte_hash: H,
52    pub max_constraint_degree: usize,
53}
54
55impl<H> StarkEngine for BabyBearByteHashEngine<H>
56where
57    H: CryptographicHasher<u8, [u8; 32]> + Clone + Send + Sync,
58{
59    type SC = BabyBearByteHashConfig<H>;
60    type PB = CpuBackend<Self::SC>;
61    type PD = CpuDevice<Self::SC>;
62
63    fn config(&self) -> &BabyBearByteHashConfig<H> {
64        &self.device.config
65    }
66
67    fn device(&self) -> &CpuDevice<BabyBearByteHashConfig<H>> {
68        &self.device
69    }
70
71    fn prover(&self) -> MultiTraceStarkProver<BabyBearByteHashConfig<H>> {
72        MultiTraceStarkProver::new(
73            CpuBackend::default(),
74            self.device.clone(),
75            self.new_challenger(),
76        )
77    }
78
79    fn max_constraint_degree(&self) -> Option<usize> {
80        Some(self.max_constraint_degree)
81    }
82
83    fn new_challenger(&self) -> Challenger<H> {
84        Challenger::from_hasher(vec![], self.byte_hash.clone())
85    }
86}
87
88/// `pcs_log_degree` is the upper bound on the log_2(PCS polynomial degree).
89pub fn default_engine<H>(byte_hash: H) -> BabyBearByteHashEngine<H>
90where
91    H: CryptographicHasher<u8, [u8; 32]> + Clone,
92{
93    engine_from_byte_hash(byte_hash, SecurityParameters::standard_fast())
94}
95
96pub fn engine_from_byte_hash<H>(
97    byte_hash: H,
98    security_params: SecurityParameters,
99) -> BabyBearByteHashEngine<H>
100where
101    H: CryptographicHasher<u8, [u8; 32]> + Clone,
102{
103    let fri_params = security_params.fri_params;
104    let max_constraint_degree = fri_params.max_constraint_degree();
105    let config = config_from_byte_hash(byte_hash.clone(), security_params);
106    BabyBearByteHashEngine {
107        device: CpuDevice::new(Arc::new(config), fri_params.log_blowup),
108        byte_hash,
109        fri_params,
110        max_constraint_degree,
111    }
112}
113
114pub fn config_from_byte_hash<H>(
115    byte_hash: H,
116    security_params: SecurityParameters,
117) -> BabyBearByteHashConfig<H>
118where
119    H: CryptographicHasher<u8, [u8; 32]> + Clone,
120{
121    let field_hash = FieldHash::new(byte_hash.clone());
122    let compress = Compress::new(byte_hash.clone());
123    let val_mmcs = ValMmcs::new(field_hash, compress);
124    let challenge_mmcs = ChallengeMmcs::new(val_mmcs.clone());
125    let dft = Dft::default();
126    let SecurityParameters {
127        fri_params,
128        log_up_params,
129        deep_ali_params,
130    } = security_params;
131    let fri_config = P3FriParameters {
132        log_blowup: fri_params.log_blowup,
133        log_final_poly_len: fri_params.log_final_poly_len,
134        num_queries: fri_params.num_queries,
135        commit_proof_of_work_bits: fri_params.commit_proof_of_work_bits,
136        query_proof_of_work_bits: fri_params.query_proof_of_work_bits,
137        mmcs: challenge_mmcs,
138    };
139    let pcs = Pcs::new(dft, val_mmcs, fri_config);
140    let challenger = Challenger::from_hasher(vec![], byte_hash);
141    let rap_phase = FriLogUpPhase::new(log_up_params, fri_params.log_blowup);
142    BabyBearByteHashConfig::new(pcs, challenger, rap_phase, deep_ali_params)
143}
144
145pub trait BabyBearByteHashEngineWithDefaultHash<H>
146where
147    H: CryptographicHasher<u8, [u8; 32]> + Clone,
148{
149    fn default_hash() -> H;
150}
151
152impl<H: CryptographicHasher<u8, [u8; 32]> + Clone + Send + Sync> StarkFriEngine
153    for BabyBearByteHashEngine<H>
154where
155    BabyBearByteHashEngine<H>: BabyBearByteHashEngineWithDefaultHash<H>,
156{
157    fn new(fri_params: FriParameters) -> Self {
158        let security_params = SecurityParameters::new_baby_bear_100_bits(fri_params);
159        engine_from_byte_hash(Self::default_hash(), security_params)
160    }
161    fn fri_params(&self) -> FriParameters {
162        self.fri_params
163    }
164}
openvm_stark_sdk/config/baby_bear_bytehash.rs

openvm_stark_sdk/config/
baby_bear_bytehash.rs
