gnark-plonky2-verifier/poseidon/poseidon.go
poseidon/poseidon.goRaw
1package poseidon
2
3import (
4 "github.com/consensys/gnark/frontend"
5 "github.com/succinctlabs/gnark-plonky2-verifier/field"
6)
7
8const HALF_N_FULL_ROUNDS = 4
9const N_FULL_ROUNDS_TOTAL = 2 * HALF_N_FULL_ROUNDS
10const N_PARTIAL_ROUNDS = 22
11const N_ROUNDS = N_FULL_ROUNDS_TOTAL + N_PARTIAL_ROUNDS
12const MAX_WIDTH = 12
13const SPONGE_WIDTH = 12
14const SPONGE_RATE = 8
15
16type PoseidonState = [SPONGE_WIDTH]field.F
17type PoseidonStateExtension = [SPONGE_WIDTH]field.QuadraticExtension
18
19type PoseidonChip struct {
20 api frontend.API `gnark:"-"`
21 fieldAPI field.FieldAPI `gnark:"-"`
22 qeAPI *field.QuadraticExtensionAPI `gnark:"-"`
23}
24
25func NewPoseidonChip(api frontend.API, fieldAPI field.FieldAPI, qeAPI *field.QuadraticExtensionAPI) *PoseidonChip {
26 return &PoseidonChip{api: api, fieldAPI: fieldAPI, qeAPI: qeAPI}
27}
28
29func (c *PoseidonChip) Poseidon(input PoseidonState) PoseidonState {
30 state := input
31 roundCounter := 0
32 state = c.FullRounds(state, &roundCounter)
33 state = c.PartialRounds(state, &roundCounter)
34 state = c.FullRounds(state, &roundCounter)
35 return state
36}
37
38func (c *PoseidonChip) HashNToMNoPad(input []field.F, nbOutputs int) []field.F {
39 var state PoseidonState
40
41 for i := 0; i < SPONGE_WIDTH; i++ {
42 state[i] = field.ZERO_F
43 }
44
45 for i := 0; i < len(input); i += SPONGE_RATE {
46 for j := 0; j < SPONGE_RATE; j++ {
47 if i+j < len(input) {
48 state[j] = input[i+j]
49 }
50 }
51 state = c.Poseidon(state)
52 }
53
54 var outputs []field.F
55
56 for {
57 for i := 0; i < SPONGE_RATE; i++ {
58 outputs = append(outputs, state[i])
59 if len(outputs) == nbOutputs {
60 return outputs
61 }
62 }
63 state = c.Poseidon(state)
64 }
65}
66
67func (c *PoseidonChip) HashNoPad(input []field.F) Hash {
68 var hash Hash
69 copy(hash[:], c.HashNToMNoPad(input, 4))
70 return hash
71}
72
73func (c *PoseidonChip) FullRounds(state PoseidonState, roundCounter *int) PoseidonState {
74 for i := 0; i < HALF_N_FULL_ROUNDS; i++ {
75 state = c.ConstantLayer(state, roundCounter)
76 state = c.SBoxLayer(state)
77 state = c.MdsLayer(state)
78 *roundCounter += 1
79 }
80 return state
81}
82
83func (c *PoseidonChip) PartialRounds(state PoseidonState, roundCounter *int) PoseidonState {
84 state = c.PartialFirstConstantLayer(state)
85 state = c.MdsPartialLayerInit(state)
86
87 for i := 0; i < N_PARTIAL_ROUNDS; i++ {
88 state[0] = c.SBoxMonomial(state[0])
89 state[0] = c.fieldAPI.Add(state[0], FAST_PARTIAL_ROUND_CONSTANTS[i])
90 state = c.MdsPartialLayerFast(state, i)
91 }
92
93 *roundCounter += N_PARTIAL_ROUNDS
94
95 return state
96}
97
98func (c *PoseidonChip) ConstantLayer(state PoseidonState, roundCounter *int) PoseidonState {
99 for i := 0; i < 12; i++ {
100 if i < SPONGE_WIDTH {
101 roundConstant := ALL_ROUND_CONSTANTS[i+SPONGE_WIDTH*(*roundCounter)]
102 state[i] = c.fieldAPI.Add(state[i], roundConstant)
103 }
104 }
105 return state
106}
107
108func (c *PoseidonChip) ConstantLayerExtension(state PoseidonStateExtension, roundCounter *int) PoseidonStateExtension {
109 for i := 0; i < 12; i++ {
110 if i < SPONGE_WIDTH {
111 roundConstant := c.qeAPI.FieldToQE(ALL_ROUND_CONSTANTS[i+SPONGE_WIDTH*(*roundCounter)])
112 state[i] = c.qeAPI.AddExtension(state[i], roundConstant)
113 }
114 }
115 return state
116}
117
118func (c *PoseidonChip) SBoxMonomial(x field.F) field.F {
119 x2 := c.fieldAPI.Mul(x, x)
120 x4 := c.fieldAPI.Mul(x2, x2)
121 x3 := c.fieldAPI.Mul(x, x2)
122 return c.fieldAPI.Mul(x3, x4)
123}
124
125func (c *PoseidonChip) SBoxMonomialExtension(x field.QuadraticExtension) field.QuadraticExtension {
126 x2 := c.qeAPI.SquareExtension(x)
127 x4 := c.qeAPI.SquareExtension(x2)
128 x3 := c.qeAPI.MulExtension(x, x2)
129 return c.qeAPI.MulExtension(x3, x4)
130}
131
132func (c *PoseidonChip) SBoxLayer(state PoseidonState) PoseidonState {
133 for i := 0; i < 12; i++ {
134 if i < SPONGE_WIDTH {
135 state[i] = c.SBoxMonomial(state[i])
136 }
137 }
138 return state
139}
140
141func (c *PoseidonChip) SBoxLayerExtension(state PoseidonStateExtension) PoseidonStateExtension {
142 for i := 0; i < 12; i++ {
143 if i < SPONGE_WIDTH {
144 state[i] = c.SBoxMonomialExtension(state[i])
145 }
146 }
147 return state
148}
149
150func (c *PoseidonChip) MdsRowShf(r int, v [SPONGE_WIDTH]frontend.Variable) frontend.Variable {
151 res := ZERO_VAR
152
153 for i := 0; i < 12; i++ {
154 if i < SPONGE_WIDTH {
155 res1 := c.api.Mul(v[(i+r)%SPONGE_WIDTH], MDS_MATRIX_CIRC_VARS[i])
156 res = c.api.Add(res, res1)
157 }
158 }
159
160 res = c.api.Add(res, c.api.Mul(v[r], MDS_MATRIX_DIAG_VARS[r]))
161 return res
162}
163
164func (c *PoseidonChip) MdsRowShfExtension(r int, v [SPONGE_WIDTH]field.QuadraticExtension) field.QuadraticExtension {
165 res := c.qeAPI.FieldToQE(field.ZERO_F)
166
167 for i := 0; i < 12; i++ {
168 if i < SPONGE_WIDTH {
169 matrixVal := c.qeAPI.FieldToQE(MDS_MATRIX_CIRC[i])
170 res1 := c.qeAPI.MulExtension(v[(i+r)%SPONGE_WIDTH], matrixVal)
171 res = c.qeAPI.AddExtension(res, res1)
172 }
173 }
174
175 matrixVal := c.qeAPI.FieldToQE(MDS_MATRIX_DIAG[r])
176 res = c.qeAPI.AddExtension(res, c.qeAPI.MulExtension(v[r], matrixVal))
177 return res
178}
179
180func (c *PoseidonChip) MdsLayer(state_ PoseidonState) PoseidonState {
181 var result PoseidonState
182 for i := 0; i < SPONGE_WIDTH; i++ {
183 result[i] = field.ZERO_F
184 }
185
186 var state [SPONGE_WIDTH]frontend.Variable
187 for i := 0; i < SPONGE_WIDTH; i++ {
188 reducedState := c.fieldAPI.Reduce(state_[i])
189 //state[i] = c.api.FromBinary(c.fieldAPI.ToBits(reducedState)...)
190 state[i] = reducedState.Limbs[0]
191 }
192
193 for r := 0; r < 12; r++ {
194 if r < SPONGE_WIDTH {
195 sum := c.MdsRowShf(r, state)
196 bits := c.api.ToBinary(sum)
197 result[r] = c.fieldAPI.FromBits(bits...)
198 }
199 }
200
201 return result
202}
203
204func (c *PoseidonChip) MdsLayerExtension(state_ PoseidonStateExtension) PoseidonStateExtension {
205 var result PoseidonStateExtension
206
207 for r := 0; r < 12; r++ {
208 if r < SPONGE_WIDTH {
209 sum := c.MdsRowShfExtension(r, state_)
210 result[r] = sum
211 }
212 }
213
214 return result
215}
216
217func (c *PoseidonChip) PartialFirstConstantLayer(state PoseidonState) PoseidonState {
218 for i := 0; i < 12; i++ {
219 if i < SPONGE_WIDTH {
220 state[i] = c.fieldAPI.Add(state[i], FAST_PARTIAL_FIRST_ROUND_CONSTANT[i])
221 }
222 }
223 return state
224}
225
226func (c *PoseidonChip) PartialFirstConstantLayerExtension(state PoseidonStateExtension) PoseidonStateExtension {
227 for i := 0; i < 12; i++ {
228 if i < SPONGE_WIDTH {
229 state[i] = c.qeAPI.AddExtension(state[i], c.qeAPI.FieldToQE(FAST_PARTIAL_FIRST_ROUND_CONSTANT[i]))
230 }
231 }
232 return state
233}
234
235func (c *PoseidonChip) MdsPartialLayerInit(state PoseidonState) PoseidonState {
236 var result PoseidonState
237 for i := 0; i < 12; i++ {
238 result[i] = field.ZERO_F
239 }
240
241 result[0] = state[0]
242
243 for r := 1; r < 12; r++ {
244 if r < SPONGE_WIDTH {
245 for d := 1; d < 12; d++ {
246 if d < SPONGE_WIDTH {
247 t := FAST_PARTIAL_ROUND_INITIAL_MATRIX[r-1][d-1]
248 result[d] = c.fieldAPI.Add(result[d], c.fieldAPI.Mul(state[r], t))
249 }
250 }
251 }
252 }
253
254 return result
255}
256
257func (c *PoseidonChip) MdsPartialLayerInitExtension(state PoseidonStateExtension) PoseidonStateExtension {
258 var result PoseidonStateExtension
259 for i := 0; i < 12; i++ {
260 result[i] = c.qeAPI.FieldToQE(field.ZERO_F)
261 }
262
263 result[0] = state[0]
264
265 for r := 1; r < 12; r++ {
266 if r < SPONGE_WIDTH {
267 for d := 1; d < 12; d++ {
268 if d < SPONGE_WIDTH {
269 t := c.qeAPI.FieldToQE(FAST_PARTIAL_ROUND_INITIAL_MATRIX[r-1][d-1])
270 result[d] = c.qeAPI.AddExtension(result[d], c.qeAPI.MulExtension(state[r], t))
271 }
272 }
273 }
274 }
275
276 return result
277}
278
279func (c *PoseidonChip) MdsPartialLayerFast(state PoseidonState, r int) PoseidonState {
280 dSum := ZERO_VAR
281 for i := 1; i < 12; i++ {
282 if i < SPONGE_WIDTH {
283 t := FAST_PARTIAL_ROUND_W_HATS_VARS[r][i-1]
284 reducedState := c.fieldAPI.Reduce(state[i])
285 //si := c.api.FromBinary(c.fieldAPI.ToBits(reducedState)...)
286 si := reducedState.Limbs[0]
287 dSum = c.api.Add(dSum, c.api.Mul(si, t))
288 }
289 }
290
291 reducedState := c.fieldAPI.Reduce(state[0])
292 //s0 := c.api.FromBinary(c.fieldAPI.ToBits(reducedState)...)
293 s0 := reducedState.Limbs[0]
294 dSum = c.api.Add(dSum, c.api.Mul(s0, MDS0TO0_VAR))
295 d := c.fieldAPI.FromBits(c.api.ToBinary(dSum)...)
296 //d := c.fieldAPI.NewElement(dSum)
297
298 var result PoseidonState
299 for i := 0; i < SPONGE_WIDTH; i++ {
300 result[i] = field.ZERO_F
301 }
302
303 result[0] = d
304
305 for i := 1; i < 12; i++ {
306 if i < SPONGE_WIDTH {
307 t := FAST_PARTIAL_ROUND_VS[r][i-1]
308 result[i] = c.fieldAPI.Add(state[i], c.fieldAPI.Mul(state[0], t))
309 }
310 }
311
312 return result
313}
314
315func (c *PoseidonChip) MdsPartialLayerFastExtension(state PoseidonStateExtension, r int) PoseidonStateExtension {
316 s0 := state[0]
317 mds0to0 := c.qeAPI.FieldToQE(MDS0TO0)
318 d := c.qeAPI.MulExtension(s0, mds0to0)
319 for i := 1; i < 12; i++ {
320 if i < SPONGE_WIDTH {
321 t := c.qeAPI.FieldToQE(FAST_PARTIAL_ROUND_W_HATS[r][i-1])
322 d = c.qeAPI.AddExtension(d, c.qeAPI.MulExtension(state[i], t))
323 }
324 }
325
326 var result PoseidonStateExtension
327 result[0] = d
328 for i := 1; i < 12; i++ {
329 if i < SPONGE_WIDTH {
330 t := c.qeAPI.FieldToQE(FAST_PARTIAL_ROUND_VS[r][i-1])
331 result[i] = c.qeAPI.AddExtension(c.qeAPI.MulExtension(state[0], t), state[i])
332 }
333 }
334
335 return result
336}