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pqcrypto/crypto_sign/sphincs-sha256-256s-simple/clean/thash_sha256_simple.c
Thom Wiggers aa4611a4d1 Eliminate the global state
This PR sacrifices passing some extra arguments to get rid of the global
state.

* Haraka needs state in all hash calls, this results in changes to the
  hash functions specified in `hash.h`.  The extra pointers passed would
  not be necessary for SHA256 or SHAKE256.
* SHAKE256 did not have global state, but uniformity in the implementations
  requires us to pass  around the new state context anyway. Otherwise,
  @joostrijneveld's SPHINCS+ generator doesn't really work anymore).

We introduce a new header file called `primitive.h` which defines the
required state type for the generic functions. I did not go into
replacing _all_ occurrences of state variables by the new `hash_state`
macro.
2019-07-16 15:46:27 -04:00

76 lines
2.5 KiB
C

#include <stdint.h>
#include <string.h>
#include "address.h"
#include "params.h"
#include "thash.h"
#include "sha2.h"
#include "sha256.h"
/**
* Takes an array of inblocks concatenated arrays of SPX_N bytes.
*/
static void PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash(
unsigned char *out, unsigned char *buf,
const unsigned char *in, unsigned int inblocks,
const unsigned char *pub_seed, uint32_t addr[8],
sha256ctx *state_seeded) {
unsigned char outbuf[SPX_SHA256_OUTPUT_BYTES];
sha256ctx sha2_state;
(void)pub_seed; /* Suppress an 'unused parameter' warning. */
/* Retrieve precomputed state containing pub_seed */
memcpy(&sha2_state, state_seeded, sizeof(sha256ctx));
PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_compress_address(buf, addr);
memcpy(buf + SPX_SHA256_ADDR_BYTES, in, inblocks * SPX_N);
sha256_inc_finalize(outbuf, &sha2_state, buf, SPX_SHA256_ADDR_BYTES + inblocks * SPX_N);
memcpy(out, outbuf, SPX_N);
}
/* The wrappers below ensure that we use fixed-size buffers on the stack */
void PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash_1(
unsigned char *out, const unsigned char *in,
const unsigned char *pub_seed, uint32_t addr[8],
sha256ctx *state_seeded) {
unsigned char buf[SPX_SHA256_ADDR_BYTES + 1 * SPX_N];
PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash(
out, buf, in, 1, pub_seed, addr, state_seeded);
}
void PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash_2(
unsigned char *out, const unsigned char *in,
const unsigned char *pub_seed, uint32_t addr[8],
sha256ctx *state_seeded) {
unsigned char buf[SPX_SHA256_ADDR_BYTES + 2 * SPX_N];
PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash(
out, buf, in, 2, pub_seed, addr, state_seeded);
}
void PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash_WOTS_LEN(
unsigned char *out, const unsigned char *in,
const unsigned char *pub_seed, uint32_t addr[8],
sha256ctx *state_seeded) {
unsigned char buf[SPX_SHA256_ADDR_BYTES + SPX_WOTS_LEN * SPX_N];
PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash(
out, buf, in, SPX_WOTS_LEN, pub_seed, addr, state_seeded);
}
void PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash_FORS_TREES(
unsigned char *out, const unsigned char *in,
const unsigned char *pub_seed, uint32_t addr[8],
sha256ctx *state_seeded) {
unsigned char buf[SPX_SHA256_ADDR_BYTES + SPX_FORS_TREES * SPX_N];
PQCLEAN_SPHINCSSHA256256SSIMPLE_CLEAN_thash(
out, buf, in, SPX_FORS_TREES, pub_seed, addr, state_seeded);
}