p3_baby_bear/
poseidon2.rs

1//! Implementation of Poseidon2, see: https://eprint.iacr.org/2023/323
2//!
3//! For the diffusion matrix, 1 + Diag(V), we perform a search to find an optimized
4//! vector V composed of elements with efficient multiplication algorithms in AVX2/AVX512/NEON.
5//!
6//! This leads to using small values (e.g. 1, 2, 3, 4) where multiplication is implemented using addition
7//! and inverse powers of 2 where it is possible to avoid monty reductions.
8//! Additionally, for technical reasons, having the first entry be -2 is useful.
9//!
10//! Optimized Diagonal for BabyBear16:
11//! [-2, 1, 2, 1/2, 3, 4, -1/2, -3, -4, 1/2^8, 1/4, 1/8, 1/2^27, -1/2^8, -1/16, -1/2^27].
12//! Optimized Diagonal for BabyBear24:
13//! [-2, 1, 2, 1/2, 3, 4, -1/2, -3, -4, 1/2^8, 1/4, 1/8, 1/16, 1/2^7, 1/2^9, 1/2^27, -1/2^8, -1/4, -1/8, -1/16, -1/32, -1/64, -1/2^7, -1/2^27]
14//! See poseidon2\src\diffusion.rs for information on how to double check these matrices in Sage.
15
16use p3_field::PrimeCharacteristicRing;
17use p3_monty_31::{
18    GenericPoseidon2LinearLayersMonty31, InternalLayerBaseParameters, InternalLayerParameters,
19    Poseidon2ExternalLayerMonty31, Poseidon2InternalLayerMonty31,
20};
21use p3_poseidon2::{ExternalLayerConstants, Poseidon2};
22
23use crate::{BabyBear, BabyBearParameters};
24
25pub type Poseidon2InternalLayerBabyBear<const WIDTH: usize> =
26    Poseidon2InternalLayerMonty31<BabyBearParameters, WIDTH, BabyBearInternalLayerParameters>;
27
28pub type Poseidon2ExternalLayerBabyBear<const WIDTH: usize> =
29    Poseidon2ExternalLayerMonty31<BabyBearParameters, WIDTH>;
30
31/// Degree of the chosen permutation polynomial for BabyBear, used as the Poseidon2 S-Box.
32///
33/// As p - 1 = 15 * 2^{27} the neither 3 nor 5 satisfy gcd(p - 1, D) = 1.
34/// Instead we use the next smallest available value, namely 7.
35const BABYBEAR_S_BOX_DEGREE: u64 = 7;
36
37/// An implementation of the Poseidon2 hash function specialised to run on the current architecture.
38///
39/// It acts on arrays of the form either `[BabyBear::Packing; WIDTH]` or `[BabyBear; WIDTH]`. For speed purposes,
40/// wherever possible, input arrays should of the form `[BabyBear::Packing; WIDTH]`.
41pub type Poseidon2BabyBear<const WIDTH: usize> = Poseidon2<
42    BabyBear,
43    Poseidon2ExternalLayerBabyBear<WIDTH>,
44    Poseidon2InternalLayerBabyBear<WIDTH>,
45    WIDTH,
46    BABYBEAR_S_BOX_DEGREE,
47>;
48
49/// An implementation of the matrix multiplications in the internal and external layers of Poseidon2.
50///
51/// This can act on `[A; WIDTH]` for any ring implementing `Algebra<BabyBear>`.
52/// If you have either `[BabyBear::Packing; WIDTH]` or `[BabyBear; WIDTH]` it will be much faster
53/// to use `Poseidon2BabyBear<WIDTH>` instead of building a Poseidon2 permutation using this.
54pub type GenericPoseidon2LinearLayersBabyBear =
55    GenericPoseidon2LinearLayersMonty31<BabyBearParameters, BabyBearInternalLayerParameters>;
56
57/// Initial round constants for the 16-width Poseidon2 external layer on BabyBear.
58///
59/// See https://github.com/HorizenLabs/poseidon2/blob/main/plain_implementations/src/poseidon2/poseidon2_instance_babybear.rs
60pub const BABYBEAR_RC16_EXTERNAL_INITIAL: [[BabyBear; 16]; 4] = BabyBear::new_2d_array([
61    [
62        0x69cbb6af, 0x46ad93f9, 0x60a00f4e, 0x6b1297cd, 0x23189afe, 0x732e7bef, 0x72c246de,
63        0x2c941900, 0x0557eede, 0x1580496f, 0x3a3ea77b, 0x54f3f271, 0x0f49b029, 0x47872fe1,
64        0x221e2e36, 0x1ab7202e,
65    ],
66    [
67        0x487779a6, 0x3851c9d8, 0x38dc17c0, 0x209f8849, 0x268dcee8, 0x350c48da, 0x5b9ad32e,
68        0x0523272b, 0x3f89055b, 0x01e894b2, 0x13ddedde, 0x1b2ef334, 0x7507d8b4, 0x6ceeb94e,
69        0x52eb6ba2, 0x50642905,
70    ],
71    [
72        0x05453f3f, 0x06349efc, 0x6922787c, 0x04bfff9c, 0x768c714a, 0x3e9ff21a, 0x15737c9c,
73        0x2229c807, 0x0d47f88c, 0x097e0ecc, 0x27eadba0, 0x2d7d29e4, 0x3502aaa0, 0x0f475fd7,
74        0x29fbda49, 0x018afffd,
75    ],
76    [
77        0x0315b618, 0x6d4497d1, 0x1b171d9e, 0x52861abd, 0x2e5d0501, 0x3ec8646c, 0x6e5f250a,
78        0x148ae8e6, 0x17f5fa4a, 0x3e66d284, 0x0051aa3b, 0x483f7913, 0x2cfe5f15, 0x023427ca,
79        0x2cc78315, 0x1e36ea47,
80    ],
81]);
82
83/// Final round constants for the 16-width Poseidon2's external layer on BabyBear.
84///
85/// See https://github.com/HorizenLabs/poseidon2/blob/main/plain_implementations/src/poseidon2/poseidon2_instance_babybear.rs
86pub const BABYBEAR_RC16_EXTERNAL_FINAL: [[BabyBear; 16]; 4] = BabyBear::new_2d_array([
87    [
88        0x7290a80d, 0x6f7e5329, 0x598ec8a8, 0x76a859a0, 0x6559e868, 0x657b83af, 0x13271d3f,
89        0x1f876063, 0x0aeeae37, 0x706e9ca6, 0x46400cee, 0x72a05c26, 0x2c589c9e, 0x20bd37a7,
90        0x6a2d3d10, 0x20523767,
91    ],
92    [
93        0x5b8fe9c4, 0x2aa501d6, 0x1e01ac3e, 0x1448bc54, 0x5ce5ad1c, 0x4918a14d, 0x2c46a83f,
94        0x4fcf6876, 0x61d8d5c8, 0x6ddf4ff9, 0x11fda4d3, 0x02933a8f, 0x170eaf81, 0x5a9c314f,
95        0x49a12590, 0x35ec52a1,
96    ],
97    [
98        0x58eb1611, 0x5e481e65, 0x367125c9, 0x0eba33ba, 0x1fc28ded, 0x066399ad, 0x0cbec0ea,
99        0x75fd1af0, 0x50f5bf4e, 0x643d5f41, 0x6f4fe718, 0x5b3cbbde, 0x1e3afb3e, 0x296fb027,
100        0x45e1547b, 0x4a8db2ab,
101    ],
102    [
103        0x59986d19, 0x30bcdfa3, 0x1db63932, 0x1d7c2824, 0x53b33681, 0x0673b747, 0x038a98a3,
104        0x2c5bce60, 0x351979cd, 0x5008fb73, 0x547bca78, 0x711af481, 0x3f93bf64, 0x644d987b,
105        0x3c8bcd87, 0x608758b8,
106    ],
107]);
108
109/// Round constants for the 16-width Poseidon2's internal layer on BabyBear.
110///
111/// See https://github.com/HorizenLabs/poseidon2/blob/main/plain_implementations/src/poseidon2/poseidon2_instance_babybear.rs
112pub const BABYBEAR_RC16_INTERNAL: [BabyBear; 13] = BabyBear::new_array([
113    0x5a8053c0, 0x693be639, 0x3858867d, 0x19334f6b, 0x128f0fd8, 0x4e2b1ccb, 0x61210ce0, 0x3c318939,
114    0x0b5b2f22, 0x2edb11d5, 0x213effdf, 0x0cac4606, 0x241af16d,
115]);
116
117/// A default Poseidon2 for BabyBear using the round constants from the Horizon Labs implementation.
118///
119/// See https://github.com/HorizenLabs/poseidon2/blob/main/plain_implementations/src/poseidon2/poseidon2_instance_babybear.rs
120pub fn default_babybear_poseidon2_16() -> Poseidon2BabyBear<16> {
121    Poseidon2::new(
122        ExternalLayerConstants::new(
123            BABYBEAR_RC16_EXTERNAL_INITIAL.to_vec(),
124            BABYBEAR_RC16_EXTERNAL_FINAL.to_vec(),
125        ),
126        BABYBEAR_RC16_INTERNAL.to_vec(),
127    )
128}
129
130/// Initial round constants for the 24-width Poseidon2 external layer on BabyBear.
131///
132/// See https://github.com/HorizenLabs/poseidon2/blob/main/plain_implementations/src/poseidon2/poseidon2_instance_babybear.rs
133pub const BABYBEAR_RC24_EXTERNAL_INITIAL: [[BabyBear; 24]; 4] = BabyBear::new_2d_array([
134    [
135        0x0fa20c37, 0x0795bb97, 0x12c60b9c, 0x0eabd88e, 0x096485ca, 0x07093527, 0x1b1d4e50,
136        0x30a01ace, 0x3bd86f5a, 0x69af7c28, 0x3f94775f, 0x731560e8, 0x465a0ecd, 0x574ef807,
137        0x62fd4870, 0x52ccfe44, 0x14772b14, 0x4dedf371, 0x260acd7c, 0x1f51dc58, 0x75125532,
138        0x686a4d7b, 0x54bac179, 0x31947706,
139    ],
140    [
141        0x29799d3b, 0x6e01ae90, 0x203a7a64, 0x4f7e25be, 0x72503f77, 0x45bd3b69, 0x769bd6b4,
142        0x5a867f08, 0x4fdba082, 0x251c4318, 0x28f06201, 0x6788c43a, 0x4c6d6a99, 0x357784a8,
143        0x2abaf051, 0x770f7de6, 0x1794b784, 0x4796c57a, 0x724b7a10, 0x449989a7, 0x64935cf1,
144        0x59e14aac, 0x0e620bb8, 0x3af5a33b,
145    ],
146    [
147        0x4465cc0e, 0x019df68f, 0x4af8d068, 0x08784f82, 0x0cefdeae, 0x6337a467, 0x32fa7a16,
148        0x486f62d6, 0x386a7480, 0x20f17c4a, 0x54e50da8, 0x2012cf03, 0x5fe52950, 0x09afb6cd,
149        0x2523044e, 0x5c54d0ef, 0x71c01f3c, 0x60b2c4fb, 0x4050b379, 0x5e6a70a5, 0x418543f5,
150        0x71debe56, 0x1aad2994, 0x3368a483,
151    ],
152    [
153        0x07a86f3a, 0x5ea43ff1, 0x2443780e, 0x4ce444f7, 0x146f9882, 0x3132b089, 0x197ea856,
154        0x667030c3, 0x2317d5dc, 0x0c2c48a7, 0x56b2df66, 0x67bd81e9, 0x4fcdfb19, 0x4baaef32,
155        0x0328d30a, 0x6235760d, 0x12432912, 0x0a49e258, 0x030e1b70, 0x48caeb03, 0x49e4d9e9,
156        0x1051b5c6, 0x6a36dbbe, 0x4cff27a5,
157    ],
158]);
159
160/// Final round constants for the 24-width Poseidon2's external layer on BabyBear.
161///
162/// See https://github.com/HorizenLabs/poseidon2/blob/main/plain_implementations/src/poseidon2/poseidon2_instance_babybear.rs
163pub const BABYBEAR_RC24_EXTERNAL_FINAL: [[BabyBear; 24]; 4] = BabyBear::new_2d_array([
164    [
165        0x032959ad, 0x2b18af6a, 0x55d3dc8c, 0x43bd26c8, 0x0c41595f, 0x7048d2e2, 0x00db8983,
166        0x2af563d7, 0x6e84758f, 0x611d64e1, 0x1f9977e2, 0x64163a0a, 0x5c5fc27b, 0x02e22561,
167        0x3a2d75db, 0x1ba7b71a, 0x34343f64, 0x7406b35d, 0x19df8299, 0x6ff4480a, 0x514a81c8,
168        0x57ab52ce, 0x6ad69f52, 0x3e0c0e0d,
169    ],
170    [
171        0x48126114, 0x2a9d62cc, 0x17441f23, 0x485762bb, 0x2f218674, 0x06fdc64a, 0x0861b7f2,
172        0x3b36eee6, 0x70a11040, 0x04b31737, 0x3722a872, 0x2a351c63, 0x623560dc, 0x62584ab2,
173        0x382c7c04, 0x3bf9edc7, 0x0e38fe51, 0x376f3b10, 0x5381e178, 0x3afc61c7, 0x5c1bcb4d,
174        0x6643ce1f, 0x2d0af1c1, 0x08f583cc,
175    ],
176    [
177        0x5d6ff60f, 0x6324c1e5, 0x74412fb7, 0x70c0192e, 0x0b72f141, 0x4067a111, 0x57388c4f,
178        0x351009ec, 0x0974c159, 0x539a58b3, 0x038c0cff, 0x476c0392, 0x3f7bc15f, 0x4491dd2c,
179        0x4d1fef55, 0x04936ae3, 0x58214dd4, 0x683c6aad, 0x1b42f16b, 0x6dc79135, 0x2d4e71ec,
180        0x3e2946ea, 0x59dce8db, 0x6cee892a,
181    ],
182    [
183        0x47f07350, 0x7106ce93, 0x3bd4a7a9, 0x2bfe636a, 0x430011e9, 0x001cd66a, 0x307faf5b,
184        0x0d9ef3fe, 0x6d40043a, 0x2e8f470c, 0x1b6865e8, 0x0c0e6c01, 0x4d41981f, 0x423b9d3d,
185        0x410408cc, 0x263f0884, 0x5311bbd0, 0x4dae58d8, 0x30401cea, 0x09afa575, 0x4b3d5b42,
186        0x63ac0b37, 0x5fe5bb14, 0x5244e9d4,
187    ],
188]);
189
190/// Round constants for the 24-width Poseidon2's internal layer on BabyBear.
191///
192/// See https://github.com/HorizenLabs/poseidon2/blob/main/plain_implementations/src/poseidon2/poseidon2_instance_babybear.rs
193pub const BABYBEAR_RC24_INTERNAL: [BabyBear; 21] = BabyBear::new_array([
194    0x1da78ec2, 0x730b0924, 0x3eb56cf3, 0x5bd93073, 0x37204c97, 0x51642d89, 0x66e943e8, 0x1a3e72de,
195    0x70beb1e9, 0x30ff3b3f, 0x4240d1c4, 0x12647b8d, 0x65d86965, 0x49ef4d7c, 0x47785697, 0x46b3969f,
196    0x5c7b7a0e, 0x7078fc60, 0x4f22d482, 0x482a9aee, 0x6beb839d,
197]);
198
199/// A default Poseidon2 for BabyBear using the round constants from the Horizon Labs implementation.
200///
201/// See https://github.com/HorizenLabs/poseidon2/blob/main/plain_implementations/src/poseidon2/poseidon2_instance_babybear.rs
202pub fn default_babybear_poseidon2_24() -> Poseidon2BabyBear<24> {
203    Poseidon2::new(
204        ExternalLayerConstants::new(
205            BABYBEAR_RC24_EXTERNAL_INITIAL.to_vec(),
206            BABYBEAR_RC24_EXTERNAL_FINAL.to_vec(),
207        ),
208        BABYBEAR_RC24_INTERNAL.to_vec(),
209    )
210}
211
212/// Contains data needed to define the internal layers of the Poseidon2 permutation.
213#[derive(Debug, Clone, Default)]
214pub struct BabyBearInternalLayerParameters;
215
216impl InternalLayerBaseParameters<BabyBearParameters, 16> for BabyBearInternalLayerParameters {
217    /// Perform the internal matrix multiplication: s -> (1 + Diag(V))s.
218    /// We ignore `state[0]` as it is handled separately.
219    fn internal_layer_mat_mul<R: PrimeCharacteristicRing>(state: &mut [R; 16], sum: R) {
220        // The diagonal matrix is defined by the vector:
221        // V = [-2, 1, 2, 1/2, 3, 4, -1/2, -3, -4, 1/2^8, 1/4, 1/8, 1/2^27, -1/2^8, -1/16, -1/2^27]
222        state[1] += sum.clone();
223        state[2] = state[2].double() + sum.clone();
224        state[3] = state[3].halve() + sum.clone();
225        state[4] = sum.clone() + state[4].double() + state[4].clone();
226        state[5] = sum.clone() + state[5].double().double();
227        state[6] = sum.clone() - state[6].halve();
228        state[7] = sum.clone() - (state[7].double() + state[7].clone());
229        state[8] = sum.clone() - state[8].double().double();
230        state[9] = state[9].div_2exp_u64(8);
231        state[9] += sum.clone();
232        state[10] = state[10].div_2exp_u64(2);
233        state[10] += sum.clone();
234        state[11] = state[11].div_2exp_u64(3);
235        state[11] += sum.clone();
236        state[12] = state[12].div_2exp_u64(27);
237        state[12] += sum.clone();
238        state[13] = state[13].div_2exp_u64(8);
239        state[13] = sum.clone() - state[13].clone();
240        state[14] = state[14].div_2exp_u64(4);
241        state[14] = sum.clone() - state[14].clone();
242        state[15] = state[15].div_2exp_u64(27);
243        state[15] = sum - state[15].clone();
244    }
245}
246
247impl InternalLayerBaseParameters<BabyBearParameters, 24> for BabyBearInternalLayerParameters {
248    /// Perform the internal matrix multiplication: s -> (1 + Diag(V))s.
249    /// We ignore `state[0]` as it is handled separately.
250    fn internal_layer_mat_mul<R: PrimeCharacteristicRing>(state: &mut [R; 24], sum: R) {
251        // The diagonal matrix is defined by the vector:
252        // V = [-2, 1, 2, 1/2, 3, 4, -1/2, -3, -4, 1/2^8, 1/4, 1/8, 1/16, 1/2^7, 1/2^9, 1/2^27, -1/2^8, -1/4, -1/8, -1/16, -1/32, -1/64, -1/2^7, -1/2^27]
253        state[1] += sum.clone();
254        state[2] = state[2].double() + sum.clone();
255        state[3] = state[3].halve() + sum.clone();
256        state[4] = sum.clone() + state[4].double() + state[4].clone();
257        state[5] = sum.clone() + state[5].double().double();
258        state[6] = sum.clone() - state[6].halve();
259        state[7] = sum.clone() - (state[7].double() + state[7].clone());
260        state[8] = sum.clone() - state[8].double().double();
261        state[9] = state[9].div_2exp_u64(8);
262        state[9] += sum.clone();
263        state[10] = state[10].div_2exp_u64(2);
264        state[10] += sum.clone();
265        state[11] = state[11].div_2exp_u64(3);
266        state[11] += sum.clone();
267        state[12] = state[12].div_2exp_u64(4);
268        state[12] += sum.clone();
269        state[13] = state[13].div_2exp_u64(7);
270        state[13] += sum.clone();
271        state[14] = state[14].div_2exp_u64(9);
272        state[14] += sum.clone();
273        state[15] = state[15].div_2exp_u64(27);
274        state[15] += sum.clone();
275        state[16] = state[16].div_2exp_u64(8);
276        state[16] = sum.clone() - state[16].clone();
277        state[17] = state[17].div_2exp_u64(2);
278        state[17] = sum.clone() - state[17].clone();
279        state[18] = state[18].div_2exp_u64(3);
280        state[18] = sum.clone() - state[18].clone();
281        state[19] = state[19].div_2exp_u64(4);
282        state[19] = sum.clone() - state[19].clone();
283        state[20] = state[20].div_2exp_u64(5);
284        state[20] = sum.clone() - state[20].clone();
285        state[21] = state[21].div_2exp_u64(6);
286        state[21] = sum.clone() - state[21].clone();
287        state[22] = state[22].div_2exp_u64(7);
288        state[22] = sum.clone() - state[22].clone();
289        state[23] = state[23].div_2exp_u64(27);
290        state[23] = sum - state[23].clone();
291    }
292}
293
294impl InternalLayerParameters<BabyBearParameters, 16> for BabyBearInternalLayerParameters {}
295impl InternalLayerParameters<BabyBearParameters, 24> for BabyBearInternalLayerParameters {}
296
297#[cfg(test)]
298mod tests {
299    use p3_symmetric::Permutation;
300    use rand::{Rng, SeedableRng};
301    use rand_xoshiro::Xoroshiro128Plus;
302
303    use super::*;
304
305    type F = BabyBear;
306
307    // We need to make some round constants. We use Xoroshiro128Plus for this as we can easily match this PRNG in sage.
308    // See: https://github.com/0xPolygonZero/hash-constants for the sage code used to create all these tests.
309
310    /// Test on a roughly random input.
311    /// This random input is generated by the following sage code:
312    /// set_random_seed(16)
313    /// vector([BB.random_element() for t in range(16)]).
314    #[test]
315    fn test_poseidon2_width_16_random() {
316        let mut input: [F; 16] = BabyBear::new_array([
317            894848333, 1437655012, 1200606629, 1690012884, 71131202, 1749206695, 1717947831,
318            120589055, 19776022, 42382981, 1831865506, 724844064, 171220207, 1299207443, 227047920,
319            1783754913,
320        ]);
321
322        let expected: [F; 16] = BabyBear::new_array([
323            1255099308, 941729227, 93609187, 112406640, 492658670, 1824768948, 812517469,
324            1055381989, 670973674, 1407235524, 891397172, 1003245378, 1381303998, 1564172645,
325            1399931635, 1005462965,
326        ]);
327
328        let mut rng = Xoroshiro128Plus::seed_from_u64(1);
329        let perm = Poseidon2BabyBear::new_from_rng_128(&mut rng);
330
331        perm.permute_mut(&mut input);
332        assert_eq!(input, expected);
333    }
334
335    /// Test on a roughly random input.
336    /// This random input is generated by the following sage code:
337    /// set_random_seed(24)
338    /// vector([BB.random_element() for t in range(24)]).
339    #[test]
340    fn test_poseidon2_width_24_random() {
341        let mut input: [F; 24] = BabyBear::new_array([
342            886409618, 1327899896, 1902407911, 591953491, 648428576, 1844789031, 1198336108,
343            355597330, 1799586834, 59617783, 790334801, 1968791836, 559272107, 31054313,
344            1042221543, 474748436, 135686258, 263665994, 1962340735, 1741539604, 449439011,
345            1131357108, 50869465, 1589724894,
346        ]);
347
348        let expected: [F; 24] = BabyBear::new_array([
349            249424342, 562262148, 757431114, 354243402, 57767055, 976981973, 1393169022,
350            1774550827, 1527742125, 1019514605, 1776327602, 266236737, 1412355182, 1070239213,
351            426390978, 1775539440, 1527732214, 1101406020, 1417710778, 1699632661, 413672313,
352            820348291, 1067197851, 1669055675,
353        ]);
354
355        let mut rng = Xoroshiro128Plus::seed_from_u64(1);
356        let perm = Poseidon2BabyBear::new_from_rng_128(&mut rng);
357
358        perm.permute_mut(&mut input);
359
360        assert_eq!(input, expected);
361    }
362
363    /// Test the generic internal layer against the optimized internal layer
364    /// for a random input of width 16.
365    #[test]
366    fn test_generic_internal_linear_layer_16() {
367        let mut rng = Xoroshiro128Plus::seed_from_u64(1);
368        let mut input1: [F; 16] = rng.random();
369        let mut input2 = input1;
370
371        let part_sum: F = input1[1..].iter().copied().sum();
372        let full_sum = part_sum + input1[0];
373
374        input1[0] = part_sum - input1[0];
375
376        BabyBearInternalLayerParameters::internal_layer_mat_mul(&mut input1, full_sum);
377        BabyBearInternalLayerParameters::generic_internal_linear_layer(&mut input2);
378
379        assert_eq!(input1, input2);
380    }
381
382    /// Test the generic internal layer against the optimized internal layer
383    /// for a random input of width 24.
384    #[test]
385    fn test_generic_internal_linear_layer_24() {
386        let mut rng = Xoroshiro128Plus::seed_from_u64(1);
387        let mut input1: [F; 24] = rng.random();
388        let mut input2 = input1;
389
390        let part_sum: F = input1[1..].iter().copied().sum();
391        let full_sum = part_sum + input1[0];
392
393        input1[0] = part_sum - input1[0];
394
395        BabyBearInternalLayerParameters::internal_layer_mat_mul(&mut input1, full_sum);
396        BabyBearInternalLayerParameters::generic_internal_linear_layer(&mut input2);
397
398        assert_eq!(input1, input2);
399    }
400}
p3_baby_bear/poseidon2.rs

p3_baby_bear/
poseidon2.rs
