def absorb256

bend-collections@1.0.0.0 · src/crypto/hash.bend:180

import Base
import bend-collections@1.0.0.0/src/crypto/sha/state.bend as S256
import bend-collections@1.0.0.0/src/crypto/sha/core.bend as C256

180# Compress every whole block (fuel bounds the count: any fuel >= the number of
181# blocks reads them all; fewer leaves the rest buffered, still correct). The
182# chaining state and the unread bytes; orig is the list the read r started at.
183# q is the algorithm's round parameter (48n), kept a variable for the proofs.
184def absorb256(fuel: Nat, r: Read256, orig: List<&2, U32>, +q: Nat, s: S256.State) -> Sha256State:
185  match fuel r:
186    case 0n _:
187      St256{s, orig}
188    case 1n+p Short256{}:
189      St256{s, orig}
190    case 1n+p Blk256{w0, w1, w2, w3, w4, w5, w6, w7, w8, w9, w10, w11, w12, w13, w14, w15, +rest}:
191      absorb256(p, read256_0(rest), rest, q, C256.fips_compress16(w0, w1, w2, w3, w4, w5, w6, w7, w8, w9, w10, w11, w12, w13, w14, w15, q, s))