486 lines
15 KiB
C++
486 lines
15 KiB
C++
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#include "./keccak.hpp"
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#include "../endian.hpp"
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#include "../maths.hpp"
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#include "../bitwise.hpp"
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#include <cstdlib>
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#include <cstdint>
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#include <array>
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#include <iostream>
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#if 0
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#define FOR(i,n) for(i=0; i<n; ++i)
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int LFSR86540(u8 *R) { (*R)=((*R)<<1)^(((*R)&0x80)?0x71:0); return ((*R)&2)>>1; }
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#define ROL(a,o) ((((u64)a)<<o)^(((u64)a)>>(64-o)))
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static u64 load64(const u8 *x) { ui i; u64 u=0; FOR(i,8) { u<<=8; u|=x[7-i]; } return u; }
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static void store64(u8 *x, u64 u) { ui i; FOR(i,8) { x[i]=u; u>>=8; } }
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static void xor64(u8 *x, u64 u) { ui i; FOR(i,8) { x[i]^=u; u>>=8; } }
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#define rL(x,y) load64((u8*)s+8*(x+5*y))
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#define wL(x,y,l) store64((u8*)s+8*(x+5*y),l)
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#define XL(x,y,l) xor64((u8*)s+8*(x+5*y),l)
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void KeccakF1600(void *s)
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{
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ui r,x,y,i,j,Y; u8 R=0x01; u64 C[5],D;
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for(i=0; i<24; i++) {
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/*θ*/ FOR(x,5) C[x]=rL(x,0)^rL(x,1)^rL(x,2)^rL(x,3)^rL(x,4); FOR(x,5) { D=C[(x+4)%5]^ROL(C[(x+1)%5],1); FOR(y,5) XL(x,y,D); }
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/*ρπ*/ x=1; y=r=0; D=rL(x,y); FOR(j,24) { r+=j+1; Y=(2*x+3*y)%5; x=y; y=Y; C[0]=rL(x,y); wL(x,y,ROL(D,r%64)); D=C[0]; }
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/*χ*/ FOR(y,5) { FOR(x,5) C[x]=rL(x,y); FOR(x,5) wL(x,y,C[x]^((~C[(x+1)%5])&C[(x+2)%5])); }
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/*ι*/ FOR(j,7) if (LFSR86540(&R)) XL(0,0,(u64)1<<((1<<j)-1));
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}
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}
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void Keccak(ui r, ui c, const u8 *in, u64 inLen, u8 sfx, u8 *out, u64 outLen)
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{
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/*initialize*/ u8 s[200]; ui R=r/8; ui i,b=0; FOR(i,200) s[i]=0;
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/*absorb*/ while(inLen>0) { b=(inLen<R)?inLen:R; FOR(i,b) s[i]^=in[i]; in+=b; inLen-=b; if (b==R) { KeccakF1600(s); b=0; } }
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/*pad*/ s[b]^=sfx; if((sfx&0x80)&&(b==(R-1))) KeccakF1600(s); s[R-1]^=0x80; KeccakF1600(s);
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/*squeeze*/ while(outLen>0) { b=(outLen<R)?outLen:R; FOR(i,b) out[i]=s[i]; out+=b; outLen-=b; if(outLen>0) KeccakF1600(s); }
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}
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#else
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// derived from Keccak (KCP) readable-and-compact C implementation
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/*
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Implementation by the Keccak, Keyak and Ketje Teams, namely, Guido Bertoni,
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Joan Daemen, Michaël Peeters, Gilles Van Assche and Ronny Van Keer, hereby
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denoted as "the implementer".
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For more information, feedback or questions, please refer to our websites:
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http://keccak.noekeon.org/
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http://keyak.noekeon.org/
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http://ketje.noekeon.org/
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To the extent possible under law, the implementer has waived all copyright
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and related or neighboring rights to the source code in this file.
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http://creativecommons.org/publicdomain/zero/1.0/
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*/
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/*
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================================================================
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The purpose of this source file is to demonstrate a readable and compact
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implementation of all the Keccak instances approved in the FIPS 202 standard,
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including the hash functions and the extendable-output functions (XOFs).
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We focused on clarity and on source-code compactness,
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rather than on the performance.
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The advantages of this implementation are:
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+ The source code is compact, after removing the comments, that is. :-)
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+ There are no tables with arbitrary constants.
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+ For clarity, the comments link the operations to the specifications using
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the same notation as much as possible.
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+ There is no restriction in cryptographic features. In particular,
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the SHAKE128 and SHAKE256 XOFs can produce any output length.
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+ The code does not use much RAM, as all operations are done in place.
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The drawbacks of this implementation are:
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- There is no message queue. The whole message must be ready in a buffer.
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- It is not optimized for peformance.
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The implementation is even simpler on a little endian platform. Just define the
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LITTLE_ENDIAN symbol in that case.
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For a more complete set of implementations, please refer to
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the Keccak Code Package at https://github.com/gvanas/KeccakCodePackage
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For more information, please refer to:
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* [Keccak Reference] http://keccak.noekeon.org/Keccak-reference-3.0.pdf
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* [Keccak Specifications Summary] http://keccak.noekeon.org/specs_summary.html
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This file uses UTF-8 encoding, as some comments use Greek letters.
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================================================================
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*/
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/**
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* Function to compute the Keccak[r, c] sponge function over a given input.
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* @param rate The value of the rate r.
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* @param capacity The value of the capacity c.
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* @param input Pointer to the input message.
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* @param inputByteLen The number of input bytes provided in the input message.
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* @param delimitedSuffix Bits that will be automatically appended to the end
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* of the input message, as in domain separation.
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* This is a byte containing from 0 to 7 bits
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* These <i>n</i> bits must be in the least significant bit positions
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* and must be delimited with a bit 1 at position <i>n</i>
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* (counting from 0=LSB to 7=MSB) and followed by bits 0
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* from position <i>n</i>+1 to position 7.
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* Some examples:
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* - If no bits are to be appended, then @a delimitedSuffix must be 0x01.
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* - If the 2-bit sequence 0,1 is to be appended (as for SHA3-*), @a delimitedSuffix must be 0x06.
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* - If the 4-bit sequence 1,1,1,1 is to be appended (as for SHAKE*), @a delimitedSuffix must be 0x1F.
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* - If the 7-bit sequence 1,1,0,1,0,0,0 is to be absorbed, @a delimitedSuffix must be 0x8B.
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* @param output Pointer to the buffer where to store the output.
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* @param outputByteLen The number of output bytes desired.
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* @pre One must have r+c=1600 and the rate a multiple of 8 bits in this implementation.
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*/
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/**
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* Function to compute SHAKE128 on the input message with any output length.
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*/
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void
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FIPS202_SHAKE128(const uint8_t *input, size_t inputByteLen, uint8_t *output, size_t outputByteLen)
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{
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keccak k (1344, 256, 0x1f);
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k.update (input, inputByteLen);
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k.digest (output, outputByteLen);
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}
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/**
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* Function to compute SHAKE256 on the input message with any output length.
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*/
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void FIPS202_SHAKE256(const uint8_t *input, size_t inputByteLen, uint8_t *output, size_t outputByteLen)
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{
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keccak k (1088, 512, 0x1f);
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k.update (input, inputByteLen);
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k.digest (output, outputByteLen);
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}
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/**
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* Function to compute SHA3-224 on the input message. The output length is fixed to 28 bytes.
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*/
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void FIPS202_SHA3_224(const uint8_t *input, size_t inputByteLen, uint8_t *output)
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{
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keccak k (1152, 448, 0x06);
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for (unsigned int i = 0; i < inputByteLen; ++i)
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k.update (&input[i], 1);
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//k.update (input, inputByteLen);
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k.digest (output, 28);
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}
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/**
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* Function to compute SHA3-256 on the input message. The output length is fixed to 32 bytes.
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*/
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void FIPS202_SHA3_256(const uint8_t *input, size_t inputByteLen, uint8_t *output)
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{
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keccak k (1088, 512, 0x06);
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k.update (input, inputByteLen);
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k.digest (output, 32);
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}
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/**
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* Function to compute SHA3-384 on the input message. The output length is fixed to 48 bytes.
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*/
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void FIPS202_SHA3_384(const uint8_t *input, size_t inputByteLen, uint8_t *output)
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{
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keccak k (832, 768, 0x06);
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k.update (input, inputByteLen);
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k.digest (output, 48);
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}
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/**
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* Function to compute SHA3-512 on the input message. The output length is fixed to 64 bytes.
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*/
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void FIPS202_SHA3_512(const uint8_t *input, size_t inputByteLen, uint8_t *output)
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{
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keccak k (576, 1024, 0x06);
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k.update (input, inputByteLen);
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k.digest (output, 64);
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}
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/*
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================================================================
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A readable and compact implementation of the Keccak-f[1600] permutation.
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================================================================
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*/
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static constexpr
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size_t
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i (size_t x, size_t y)
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{
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return x + 5 * y;
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}
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/**
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* Function that computes the linear feedback shift register (LFSR) used to
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* define the round constants (see [Keccak Reference, Section 1.2]).
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*/
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class lfsr86540 {
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public:
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lfsr86540 ():
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value (0x1)
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{ ; }
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bool
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update (void)
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{
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bool result = value & 0x01;
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if (value & 0x80)
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// Primitive polynomial over GF(2): x^8+x^6+x^5+x^4+1
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value = (value << 1) ^ 0x71;
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else
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value <<= 1;
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return result;
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}
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private:
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uint8_t value;
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};
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// θ step, see [Keccak Reference, Section 2.3.2]
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static void
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permute_theta (uint64_t m_words[5][5])
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{
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uint64_t C[5], D;
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// Compute the parity of the columns
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for (unsigned x = 0; x < 5; ++x)
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C[x] = m_words[0][x] ^ m_words[1][x] ^ m_words[2][x] ^ m_words[3][x] ^ m_words[4][x];
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for (unsigned x = 0; x < 5; ++x) {
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// Compute the θ effect for a given column
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D = C[(x+4)%5] ^ rotatel (C[(x+1)%5], 1);
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// Add the θ effect to the whole column
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for (unsigned y = 0; y < 5; ++y)
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m_words[y][x] ^= D;
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}
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}
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void
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permute_rho (uint64_t m_words[5][5])
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{
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m_words[0][1] = rotatel (m_words[0][1], 1);
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m_words[0][2] = rotatel (m_words[0][2], 62);
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m_words[0][3] = rotatel (m_words[0][3], 28);
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m_words[0][4] = rotatel (m_words[0][4], 27);
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m_words[1][0] = rotatel (m_words[1][0], 36);
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m_words[1][1] = rotatel (m_words[1][1], 44);
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m_words[1][2] = rotatel (m_words[1][2], 6);
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m_words[1][3] = rotatel (m_words[1][3], 55);
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m_words[1][4] = rotatel (m_words[1][4], 20);
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m_words[2][0] = rotatel (m_words[2][0], 3);
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m_words[2][1] = rotatel (m_words[2][1], 10);
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m_words[2][2] = rotatel (m_words[2][2], 43);
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m_words[2][3] = rotatel (m_words[2][3], 25);
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m_words[2][4] = rotatel (m_words[2][4], 39);
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m_words[3][0] = rotatel (m_words[3][0], 41);
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m_words[3][1] = rotatel (m_words[3][1], 45);
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m_words[3][2] = rotatel (m_words[3][2], 15);
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m_words[3][3] = rotatel (m_words[3][3], 21);
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m_words[3][4] = rotatel (m_words[3][4], 8);
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m_words[4][0] = rotatel (m_words[4][0], 18);
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m_words[4][1] = rotatel (m_words[4][1], 2);
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m_words[4][2] = rotatel (m_words[4][2], 61);
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m_words[4][3] = rotatel (m_words[4][3], 56);
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m_words[4][4] = rotatel (m_words[4][4], 14);
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return;
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for (size_t i = 1; i < 25; ++i) {
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//unsigned r = ((t+1)*(t+2)/2)%64;
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unsigned r = ((i + 1) * (i + 2) / 2) % 64;
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m_words[i/5][i%5] = rotatel (m_words[i/5][i%5], r);
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}
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}
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void
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permute_pi (uint64_t m_words[5][5])
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{
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//auto A = reinterpret_cast<uint64_t*> (m_words);
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//uint64_t A1;
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//A1 = A[1];
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//A[ 1] = A[ 6];
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//A[ 6] = A[ 9];
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//A[ 9] = A[22];
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//A[22] = A[14];
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//A[14] = A[20];
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//A[20] = A[ 2];
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//A[ 2] = A[12];
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//A[12] = A[13];
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//A[13] = A[19];
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//A[19] = A[23];
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//A[23] = A[15];
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//A[15] = A[ 4];
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//A[ 4] = A[24];
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|||
|
|
//A[24] = A[21];
|
|||
|
|
//A[21] = A[ 8];
|
|||
|
|
//A[ 8] = A[16];
|
|||
|
|
//A[16] = A[ 5];
|
|||
|
|
//A[ 5] = A[ 3];
|
|||
|
|
//A[ 3] = A[18];
|
|||
|
|
//A[18] = A[17];
|
|||
|
|
//A[17] = A[11];
|
|||
|
|
//A[11] = A[ 7];
|
|||
|
|
//A[ 7] = A[10];
|
|||
|
|
//A[10] = A1;
|
|||
|
|
//return;
|
|||
|
|
|
|||
|
|
unsigned x = 1, y = 0;
|
|||
|
|
uint64_t current = m_words[y][x];
|
|||
|
|
uint64_t temp;
|
|||
|
|
// Iterate over ((0 1)(2 3))^t * (1 0) for 0 ≤ t ≤ 23
|
|||
|
|
for (unsigned t = 0; t < 24; ++t) {
|
|||
|
|
unsigned int Y = (2*x+3*y)%5;
|
|||
|
|
x = y;
|
|||
|
|
y = Y;
|
|||
|
|
|
|||
|
|
temp = m_words[y][x];
|
|||
|
|
m_words[y][x] = current;
|
|||
|
|
current = temp;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
//for (unsigned int i = 0; i < 5; ++i)
|
|||
|
|
// for (unsigned int j = 0; j < 5; ++j)
|
|||
|
|
// m_words[j][(2*i+3*j)%5] = m_words[i][j];
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
|
|||
|
|
/**
|
|||
|
|
* Function that computes the Keccak-f[1600] permutation on the given state.
|
|||
|
|
*/
|
|||
|
|
void
|
|||
|
|
keccak::permute (void)
|
|||
|
|
{
|
|||
|
|
for (size_t i = 0; i < m_bitrate/64; ++i)
|
|||
|
|
m_words[i/5][i%5] = ltoh (m_words[i/5][i%5]);
|
|||
|
|
|
|||
|
|
lfsr86540 shift;
|
|||
|
|
|
|||
|
|
for (unsigned round = 0; round < 24; ++round) {
|
|||
|
|
permute_theta (m_words);
|
|||
|
|
permute_rho (m_words);
|
|||
|
|
permute_pi (m_words);
|
|||
|
|
|
|||
|
|
|
|||
|
|
if (0) { // === ρ and π steps (see [Keccak Reference, Sections 2.3.3 and 2.3.4]) ===
|
|||
|
|
uint64_t current, temp;
|
|||
|
|
// Start at coordinates (1 0)
|
|||
|
|
unsigned x = 1, y = 0;
|
|||
|
|
current = m_words[y][x];
|
|||
|
|
// Iterate over ((0 1)(2 3))^t * (1 0) for 0 ≤ t ≤ 23
|
|||
|
|
for (unsigned t = 0; t < 24; ++t) {
|
|||
|
|
// Compute the rotation constant r = (t+1)(t+2)/2
|
|||
|
|
unsigned int r = ((t+1)*(t+2)/2)%64;
|
|||
|
|
|
|||
|
|
// Compute ((0 1)(2 3)) * (x y)
|
|||
|
|
unsigned int Y = (2*x+3*y)%5; x = y; y = Y;
|
|||
|
|
|
|||
|
|
// Swap current and state(x,y), and rotate
|
|||
|
|
temp = m_words[y][x];
|
|||
|
|
m_words[y][x] = rotatel (current, r);
|
|||
|
|
current = temp;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
{ // === χ step (see [Keccak Reference, Section 2.3.1]) ===
|
|||
|
|
uint64_t temp[5];
|
|||
|
|
for (unsigned y = 0; y < 5; ++y) {
|
|||
|
|
// Take a copy of the plane
|
|||
|
|
for (unsigned x = 0; x < 5; ++x)
|
|||
|
|
temp[x] = m_words[y][x];
|
|||
|
|
|
|||
|
|
// Compute χ on the plane
|
|||
|
|
for(unsigned x = 0; x < 5; ++x)
|
|||
|
|
m_words[y][x] = temp[x] ^((~temp[(x+1)%5]) & temp[(x+2)%5]);
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
{ // === ι step (see [Keccak Reference, Section 2.3.5]) ===
|
|||
|
|
for (unsigned j = 0; j < 7; ++j) {
|
|||
|
|
unsigned int bitPosition = (1 << j) - 1; //2^j-1
|
|||
|
|
if (shift.update ())
|
|||
|
|
m_words[0][0] ^= uint64_t{1} << bitPosition;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
================================================================
|
|||
|
|
A readable and compact implementation of the Keccak sponge functions
|
|||
|
|
that use the Keccak-f[1600] permutation.
|
|||
|
|
================================================================
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
#include <cstring>
|
|||
|
|
|
|||
|
|
|
|||
|
|
void
|
|||
|
|
keccak::update (
|
|||
|
|
const uint8_t *input,
|
|||
|
|
size_t len
|
|||
|
|
) {
|
|||
|
|
unsigned int byterate = m_bitrate / 8;
|
|||
|
|
|
|||
|
|
while (len) {
|
|||
|
|
auto chunk = util::min (len, byterate - m_cursor);
|
|||
|
|
|
|||
|
|
for (unsigned i = 0; i < chunk; ++i)
|
|||
|
|
m_bytes[m_cursor++] ^= *input++;
|
|||
|
|
|
|||
|
|
len -= chunk;
|
|||
|
|
|
|||
|
|
if (m_cursor == byterate) {
|
|||
|
|
permute ();
|
|||
|
|
m_cursor = 0;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
|
|||
|
|
void
|
|||
|
|
keccak::digest (
|
|||
|
|
uint8_t *output,
|
|||
|
|
size_t len
|
|||
|
|
) {
|
|||
|
|
unsigned byterate = m_bitrate / 8u;
|
|||
|
|
|
|||
|
|
// === Do the padding and switch to the squeezing phase ===
|
|||
|
|
// Absorb the last few bits and add the first bit of padding (which
|
|||
|
|
// coincides with the delimiter in delimitedSuffix)
|
|||
|
|
m_bytes[m_cursor] ^= m_suffix;
|
|||
|
|
|
|||
|
|
// If the first bit of padding is at position rate-1, we need a whole new
|
|||
|
|
// block for the second bit of padding
|
|||
|
|
if (m_suffix & 0x80 && m_cursor == byterate - 1)
|
|||
|
|
permute ();
|
|||
|
|
|
|||
|
|
// Add the second bit of padding
|
|||
|
|
m_bytes[byterate - 1] ^= 0x80;
|
|||
|
|
|
|||
|
|
// === Squeeze out all the output blocks ===
|
|||
|
|
while (len) {
|
|||
|
|
permute ();
|
|||
|
|
|
|||
|
|
auto chunk = util::min (len, byterate);
|
|||
|
|
std::copy_n (m_bytes.begin (), chunk, output);
|
|||
|
|
|
|||
|
|
output += chunk;
|
|||
|
|
len -= chunk;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
|
|||
|
|
keccak::keccak (unsigned _bitrate,
|
|||
|
|
unsigned _capacity,
|
|||
|
|
uint8_t _suffix):
|
|||
|
|
m_bitrate (_bitrate),
|
|||
|
|
m_capacity (_capacity),
|
|||
|
|
m_suffix (_suffix),
|
|||
|
|
m_cursor (0)
|
|||
|
|
{
|
|||
|
|
// we could support bitrates that are multiples of 8, but 64 simplifies
|
|||
|
|
// some state handling, and the SHA-3 constants are all multiples of 64
|
|||
|
|
// bits anyway.
|
|||
|
|
if ((m_bitrate + m_capacity) / 8 != sizeof (m_bytes) || m_bitrate % 64 != 0)
|
|||
|
|
throw "error";
|
|||
|
|
|
|||
|
|
std::fill (std::begin (m_bytes), std::end (m_bytes), 0);
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
#endif
|