diff options
Diffstat (limited to 'sha3.c')
| -rw-r--r-- | sha3.c | 191 |
1 files changed, 191 insertions, 0 deletions
@@ -0,0 +1,191 @@ +// sha3.c +// 19-Nov-11 Markku-Juhani O. Saarinen <mjos@iki.fi> + +// Revised 07-Aug-15 to match with official release of FIPS PUB 202 "SHA3" +// Revised 03-Sep-15 for portability + OpenSSL - style API + +#include "sha3.h" + +// update the state with given number of rounds + +void sha3_keccakf(uint64_t st[25]) +{ + // constants + const uint64_t keccakf_rndc[24] = { + 0x0000000000000001, 0x0000000000008082, 0x800000000000808a, + 0x8000000080008000, 0x000000000000808b, 0x0000000080000001, + 0x8000000080008081, 0x8000000000008009, 0x000000000000008a, + 0x0000000000000088, 0x0000000080008009, 0x000000008000000a, + 0x000000008000808b, 0x800000000000008b, 0x8000000000008089, + 0x8000000000008003, 0x8000000000008002, 0x8000000000000080, + 0x000000000000800a, 0x800000008000000a, 0x8000000080008081, + 0x8000000000008080, 0x0000000080000001, 0x8000000080008008 + }; + const int keccakf_rotc[24] = { + 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 2, 14, + 27, 41, 56, 8, 25, 43, 62, 18, 39, 61, 20, 44 + }; + const int keccakf_piln[24] = { + 10, 7, 11, 17, 18, 3, 5, 16, 8, 21, 24, 4, + 15, 23, 19, 13, 12, 2, 20, 14, 22, 9, 6, 1 + }; + + // variables + int i, j, r; + uint64_t t, bc[5]; + +#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__ + uint8_t *v; + + // endianess conversion. this is redundant on little-endian targets + for (i = 0; i < 25; i++) { + v = (uint8_t *) &st[i]; + st[i] = ((uint64_t) v[0]) | (((uint64_t) v[1]) << 8) | + (((uint64_t) v[2]) << 16) | (((uint64_t) v[3]) << 24) | + (((uint64_t) v[4]) << 32) | (((uint64_t) v[5]) << 40) | + (((uint64_t) v[6]) << 48) | (((uint64_t) v[7]) << 56); + } +#endif + + // actual iteration + for (r = 0; r < KECCAKF_ROUNDS; r++) { + + // Theta + for (i = 0; i < 5; i++) + bc[i] = st[i] ^ st[i + 5] ^ st[i + 10] ^ st[i + 15] ^ st[i + 20]; + + for (i = 0; i < 5; i++) { + t = bc[(i + 4) % 5] ^ ROTL64(bc[(i + 1) % 5], 1); + for (j = 0; j < 25; j += 5) + st[j + i] ^= t; + } + + // Rho Pi + t = st[1]; + for (i = 0; i < 24; i++) { + j = keccakf_piln[i]; + bc[0] = st[j]; + st[j] = ROTL64(t, keccakf_rotc[i]); + t = bc[0]; + } + + // Chi + for (j = 0; j < 25; j += 5) { + for (i = 0; i < 5; i++) + bc[i] = st[j + i]; + for (i = 0; i < 5; i++) + st[j + i] ^= (~bc[(i + 1) % 5]) & bc[(i + 2) % 5]; + } + + // Iota + st[0] ^= keccakf_rndc[r]; + } + +#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__ + // endianess conversion. this is redundant on little-endian targets + for (i = 0; i < 25; i++) { + v = (uint8_t *) &st[i]; + t = st[i]; + v[0] = t & 0xFF; + v[1] = (t >> 8) & 0xFF; + v[2] = (t >> 16) & 0xFF; + v[3] = (t >> 24) & 0xFF; + v[4] = (t >> 32) & 0xFF; + v[5] = (t >> 40) & 0xFF; + v[6] = (t >> 48) & 0xFF; + v[7] = (t >> 56) & 0xFF; + } +#endif +} + +// Initialize the context for SHA3 + +int sha3_init(sha3_ctx_t *c, int mdlen) +{ + int i; + + for (i = 0; i < 25; i++) + c->st.q[i] = 0; + c->mdlen = mdlen; + c->rsiz = 200 - 2 * mdlen; + c->pt = 0; + + return 1; +} + +// update state with more data + +int sha3_update(sha3_ctx_t *c, const void *data, size_t len) +{ + size_t i; + int j; + + j = c->pt; + for (i = 0; i < len; i++) { + c->st.b[j++] ^= ((const uint8_t *) data)[i]; + if (j >= c->rsiz) { + sha3_keccakf(c->st.q); + j = 0; + } + } + c->pt = j; + + return 1; +} + +// finalize and output a hash + +int sha3_final(void *md, sha3_ctx_t *c) +{ + int i; + + c->st.b[c->pt] ^= 0x06; + c->st.b[c->rsiz - 1] ^= 0x80; + sha3_keccakf(c->st.q); + + for (i = 0; i < c->mdlen; i++) { + ((uint8_t *) md)[i] = c->st.b[i]; + } + + return 1; +} + +// compute a SHA-3 hash (md) of given byte length from "in" + +void *sha3(const void *in, size_t inlen, void *md, int mdlen) +{ + sha3_ctx_t sha3; + + sha3_init(&sha3, mdlen); + sha3_update(&sha3, in, inlen); + sha3_final(md, &sha3); + + return md; +} + +// SHAKE128 and SHAKE256 extensible-output functionality + +void shake_xof(sha3_ctx_t *c) +{ + c->st.b[c->pt] ^= 0x1F; + c->st.b[c->rsiz - 1] ^= 0x80; + sha3_keccakf(c->st.q); + c->pt = 0; +} + +void shake_out(sha3_ctx_t *c, void *out, size_t len) +{ + size_t i; + int j; + + j = c->pt; + for (i = 0; i < len; i++) { + if (j >= c->rsiz) { + sha3_keccakf(c->st.q); + j = 0; + } + ((uint8_t *) out)[i] = c->st.b[j++]; + } + c->pt = j; +} + |