Incremental Keccak API added

- needed for TREZOR integration
This commit is contained in:
Dusan Klinec 2018-08-14 23:23:00 +02:00
parent 0dddfeacc9
commit 4e081001c0
No known key found for this signature in database
GPG key ID: 6337E118CCBCE103
2 changed files with 88 additions and 0 deletions

View file

@ -132,3 +132,77 @@ void keccak1600(const uint8_t *in, size_t inlen, uint8_t *md)
{
keccak(in, inlen, md, sizeof(state_t));
}
#define KECCAK_FINALIZED 0x80000000
#define KECCAK_BLOCKLEN 136
#define KECCAK_WORDS 17
#define KECCAK_DIGESTSIZE 32
#define IS_ALIGNED_64(p) (0 == (7 & ((const char*)(p) - (const char*)0)))
#define KECCAK_PROCESS_BLOCK(st, block) { \
for (int i_ = 0; i_ < KECCAK_WORDS; i_++){ \
((st))[i_] ^= ((block))[i_]; \
}; \
keccakf(st, KECCAK_ROUNDS); }
void keccak_init(KECCAK_CTX * ctx){
memset(ctx, 0, sizeof(KECCAK_CTX));
}
void keccak_update(KECCAK_CTX * ctx, const uint8_t *in, size_t inlen){
if (ctx->rest & KECCAK_FINALIZED) {
local_abort("Bad keccak use");
}
const size_t idx = ctx->rest;
ctx->rest = (ctx->rest + inlen) % KECCAK_BLOCKLEN;
// fill partial block
if (idx) {
size_t left = KECCAK_BLOCKLEN - idx;
memcpy((char*)ctx->message + idx, in, (inlen < left ? inlen : left));
if (inlen < left) return;
KECCAK_PROCESS_BLOCK(ctx->hash, ctx->message);
in += left;
inlen -= left;
}
const bool is_aligned = IS_ALIGNED_64(in);
while (inlen >= KECCAK_BLOCKLEN) {
const uint64_t* aligned_message_block;
if (is_aligned) {
aligned_message_block = (uint64_t*)in;
} else {
memcpy(ctx->message, in, KECCAK_BLOCKLEN);
aligned_message_block = ctx->message;
}
KECCAK_PROCESS_BLOCK(ctx->hash, aligned_message_block);
in += KECCAK_BLOCKLEN;
inlen -= KECCAK_BLOCKLEN;
}
if (inlen) {
memcpy(ctx->message, in, inlen);
}
}
void keccak_finish(KECCAK_CTX * ctx, uint8_t *md){
if (!(ctx->rest & KECCAK_FINALIZED))
{
// clear the rest of the data queue
memset((char*)ctx->message + ctx->rest, 0, KECCAK_BLOCKLEN - ctx->rest);
((char*)ctx->message)[ctx->rest] |= 0x01;
((char*)ctx->message)[KECCAK_BLOCKLEN - 1] |= 0x80;
// process final block
KECCAK_PROCESS_BLOCK(ctx->hash, ctx->message);
ctx->rest = KECCAK_FINALIZED; // mark context as finalized
}
static_assert(KECCAK_BLOCKLEN > KECCAK_DIGESTSIZE, "");
if (md) {
memcpy(md, ctx->hash, KECCAK_DIGESTSIZE);
}
}

View file

@ -15,6 +15,17 @@
#define ROTL64(x, y) (((x) << (y)) | ((x) >> (64 - (y))))
#endif
// SHA3 Algorithm context.
typedef struct KECCAK_CTX
{
// 1600 bits algorithm hashing state
uint64_t hash[25];
// 1088-bit buffer for leftovers, block size = 136 B for 256-bit keccak
uint64_t message[17];
// count of bytes in the message[] buffer
size_t rest;
} KECCAK_CTX;
// compute a keccak hash (md) of given byte length from "in"
void keccak(const uint8_t *in, size_t inlen, uint8_t *md, int mdlen);
@ -23,4 +34,7 @@ void keccakf(uint64_t st[25], int norounds);
void keccak1600(const uint8_t *in, size_t inlen, uint8_t *md);
void keccak_init(KECCAK_CTX * ctx);
void keccak_update(KECCAK_CTX * ctx, const uint8_t *in, size_t inlen);
void keccak_finish(KECCAK_CTX * ctx, uint8_t *md);
#endif