From db7d3deb03653d194c4de1fd02e755c507afbd81 Mon Sep 17 00:00:00 2001 From: Ko- Date: Fri, 7 Jun 2019 11:43:10 +0200 Subject: [PATCH] Add cSHAKE{128,256} to common. --- common/sp800-185.c | 138 +++++++++++++++++++++++++++++++++++++++++++++ common/sp800-185.h | 23 ++++++++ 2 files changed, 161 insertions(+) create mode 100644 common/sp800-185.c create mode 100644 common/sp800-185.h diff --git a/common/sp800-185.c b/common/sp800-185.c new file mode 100644 index 00000000..929f8518 --- /dev/null +++ b/common/sp800-185.c @@ -0,0 +1,138 @@ +#include +#include + +#include "sp800-185.h" + +static size_t left_encode(uint8_t *encbuf, size_t value) +{ + size_t n, i, v; + + for ( v = value, n = 0; v && (n < sizeof(size_t)); ++n, v >>= 8 ) + ; /* empty */ + if (n == 0) + n = 1; + for ( i = 1; i <= n; ++i ) + { + encbuf[i] = (uint8_t)(value >> (8 * (n-i))); + } + encbuf[0] = (uint8_t)n; + return n + 1; +} + +void cshake128_inc_init(shake128incctx *state, const uint8_t *name, size_t namelen, const uint8_t *cstm, size_t cstmlen) { + uint8_t encbuf[sizeof(size_t)+1]; + + shake128_inc_init(state); + + shake128_inc_absorb(state, encbuf, left_encode(encbuf, SHAKE128_RATE)); + + shake128_inc_absorb(state, encbuf, left_encode(encbuf, namelen * 8)); + shake128_inc_absorb(state, name, namelen); + + shake128_inc_absorb(state, encbuf, left_encode(encbuf, cstmlen * 8)); + shake128_inc_absorb(state, cstm, cstmlen); + + if (state->ctx[25] != 0) { + state->ctx[25] = SHAKE128_RATE - 1; + encbuf[0] = 0; + shake128_inc_absorb(state, encbuf, 1); + } +} + +void cshake128_inc_absorb(shake128incctx *state, const uint8_t *input, size_t inlen) { + shake128_inc_absorb(state, input, inlen); +} + +void cshake128_inc_finalize(shake128incctx *state) { + state->ctx[state->ctx[25] >> 3] ^= (uint64_t)0x04 << (8 * (state->ctx[25] & 0x07)); + state->ctx[(SHAKE128_RATE - 1) >> 3] ^= (uint64_t)128 << (8 * ((SHAKE128_RATE - 1) & 0x07)); + state->ctx[25] = 0; +} + +void cshake128_inc_squeeze(uint8_t *output, size_t outlen, shake128incctx *state) { + shake128_inc_squeeze(output, outlen, state); +} + +void cshake256_inc_init(shake256incctx *state, const uint8_t *name, size_t namelen, const uint8_t *cstm, size_t cstmlen) { + uint8_t encbuf[sizeof(size_t)+1]; + + shake256_inc_init(state); + + shake256_inc_absorb(state, encbuf, left_encode(encbuf, SHAKE256_RATE)); + + shake256_inc_absorb(state, encbuf, left_encode(encbuf, namelen * 8)); + shake256_inc_absorb(state, name, namelen); + + shake256_inc_absorb(state, encbuf, left_encode(encbuf, cstmlen * 8)); + shake256_inc_absorb(state, cstm, cstmlen); + + if (state->ctx[25] != 0) { + state->ctx[25] = SHAKE256_RATE - 1; + encbuf[0] = 0; + shake256_inc_absorb(state, encbuf, 1); + } +} + +void cshake256_inc_absorb(shake256incctx *state, const uint8_t *input, size_t inlen) { + shake256_inc_absorb(state, input, inlen); +} + +void cshake256_inc_finalize(shake256incctx *state) { + state->ctx[state->ctx[25] >> 3] ^= (uint64_t)0x04 << (8 * (state->ctx[25] & 0x07)); + state->ctx[(SHAKE256_RATE - 1) >> 3] ^= (uint64_t)128 << (8 * ((SHAKE256_RATE - 1) & 0x07)); + state->ctx[25] = 0; +} + +void cshake256_inc_squeeze(uint8_t *output, size_t outlen, shake256incctx *state) { + shake256_inc_squeeze(output, outlen, state); +} + +/************************************************* + * Name: cshake128 + * + * Description: cSHAKE128 XOF with non-incremental API + * + * Arguments: - uint8_t *output: pointer to output + * - size_t outlen: requested output length in bytes + * - const uint8_t *name: pointer to function-name string + * - size_t namelen: length of function-name string in bytes + * - const uint8_t *cstm: pointer to non-empty customization string + * - size_t cstmlen: length of customization string in bytes + * - const uint8_t *input: pointer to input + * - size_t inlen: length of input in bytes + **************************************************/ +void cshake128(uint8_t *output, size_t outlen, + const uint8_t *name, size_t namelen, + const uint8_t *cstm, size_t cstmlen, + const uint8_t *input, size_t inlen) { + shake128incctx state; + cshake128_inc_init(&state, name, namelen, cstm, cstmlen); + cshake128_inc_absorb(&state, input, inlen); + cshake128_inc_finalize(&state); + cshake128_inc_squeeze(output, outlen, &state); +} + +/************************************************* + * Name: cshake256 + * + * Description: cSHAKE256 XOF with non-incremental API + * + * Arguments: - uint8_t *output: pointer to output + * - size_t outlen: requested output length in bytes + * - const uint8_t *name: pointer to function-name string + * - size_t namelen: length of function-name string in bytes + * - const uint8_t *cstm: pointer to non-empty customization string + * - size_t cstmlen: length of customization string in bytes + * - const uint8_t *input: pointer to input + * - size_t inlen: length of input in bytes + **************************************************/ +void cshake256(uint8_t *output, size_t outlen, + const uint8_t *name, size_t namelen, + const uint8_t *cstm, size_t cstmlen, + const uint8_t *input, size_t inlen) { + shake256incctx state; + cshake256_inc_init(&state, name, namelen, cstm, cstmlen); + cshake256_inc_absorb(&state, input, inlen); + cshake256_inc_finalize(&state); + cshake256_inc_squeeze(output, outlen, &state); +} diff --git a/common/sp800-185.h b/common/sp800-185.h new file mode 100644 index 00000000..06781523 --- /dev/null +++ b/common/sp800-185.h @@ -0,0 +1,23 @@ +#ifndef SP800_185_H +#define SP800_185_H + +#include +#include + +#include "fips202.h" + +void cshake128_inc_init(shake128incctx *state, const uint8_t *name, size_t namelen, const uint8_t *cstm, size_t cstmlen); +void cshake128_inc_absorb(shake128incctx *state, const uint8_t *input, size_t inlen); +void cshake128_inc_finalize(shake128incctx *state); +void cshake128_inc_squeeze(uint8_t *output, size_t outlen, shake128incctx *state); + +void cshake128(uint8_t *output, size_t outlen, const uint8_t *name, size_t namelen, const uint8_t *cstm, size_t cstmlen, const uint8_t *input, size_t inlen); + +void cshake256_inc_init(shake256incctx *state, const uint8_t *name, size_t namelen, const uint8_t *cstm, size_t cstmlen); +void cshake256_inc_absorb(shake256incctx *state, const uint8_t *input, size_t inlen); +void cshake256_inc_finalize(shake256incctx *state); +void cshake256_inc_squeeze(uint8_t *output, size_t outlen, shake256incctx *state); + +void cshake256(uint8_t *output, size_t outlen, const uint8_t *name, size_t namelen, const uint8_t* cstm, size_t cstmlen, const uint8_t *input, size_t inlen); + +#endif