/* See LICENSE file for copyright and license details. */
#include "common.h"
/**
* Unified implementation (what can unified without performance impact)
* of the chunk processing for all SHA-2 functions
*
* @param A Wordsize-dependent constant, take a look at the code
* @param B Wordsize-dependent constant, take a look at the code
* @param C Wordsize-dependent constant, take a look at the code
* @param D Wordsize-dependent constant, take a look at the code
* @param E Wordsize-dependent constant, take a look at the code
* @param F Wordsize-dependent constant, take a look at the code
* @param G Wordsize-dependent constant, take a look at the code
* @param H Wordsize-dependent constant, take a look at the code
* @param I Wordsize-dependent constant, take a look at the code
* @param J Wordsize-dependent constant, take a look at the code
* @param K Wordsize-dependent constant, take a look at the code
* @param L Wordsize-dependent constant, take a look at the code
* @param WORD_T `__typeof()` on any wordsize-dependent variable, with exact size
* @param k Round constants
* @param w Words
* @param h Hash values
* @param work_h Space for temporary hash values
*/
#define SHA2_IMPLEMENTATION(A, B, C, D, E, F, G, H, I, J, K, L, WORD_T, k, w, h, work_h)\
memcpy(work_h, h, sizeof(work_h));\
\
memset(w, 0, 16 * sizeof(*(w)));\
for (i = 0; i < 16; i++)\
for (j = 0; j < sizeof(WORD_T); j++)\
w[i] |= ((WORD_T)(state->chunk[(i + 1) * sizeof(WORD_T) - j - 1])) << (j << 3);\
\
for (i = 16; i < sizeof(k) / sizeof(*(k)); i++) {\
w[i] = w[i - 16] + w[i - 7];\
w[i] += ROTR(w[i - 15], A) ^ ROTR(w[i - 15], B) ^ (w[i - 15] >> (C));\
w[i] += ROTR(w[i - 2], D) ^ ROTR(w[i - 2], E) ^ (w[i - 2] >> (F));\
}\
\
for (i = 0; i < sizeof(k) / sizeof(*(k)); i++) {\
s1 = (work_h[4] & work_h[5]) ^ (work_h[6] & ~(work_h[4]));\
s1 += work_h[7] + k[i] + w[i];\
s0 = (work_h[0] & work_h[1]) ^ (work_h[0] & work_h[2]) ^ (work_h[1] & work_h[2]);\
s1 += ROTR(work_h[4], G) ^ ROTR(work_h[4], H) ^ ROTR(work_h[4], I);\
s0 += ROTR(work_h[0], J) ^ ROTR(work_h[0], K) ^ ROTR(work_h[0], L);\
\
memmove(work_h + 1, work_h, 7 * sizeof(*(work_h)));\
work_h[4] += s1;\
work_h[0] = s1 + s0;\
}\
\
for (i = 0; i < 8; i++)\
h[i] += work_h[i]
/**
* Process a chunk using SHA-256
*
* @param state The hashing state
*/
#if defined(__GNUC__)
__attribute__((__nonnull__, __nothrow__))
#endif
static void
process256(struct libsha2_state *restrict state)
{
uint32_t s0, s1;
size_t i, j;
#if defined(__GNUC__)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wmemset-elt-size"
#endif
#define ROTR(X, N) (((X) >> (N)) | ((X) << ((sizeof(uint32_t) * 8) - (N))))
SHA2_IMPLEMENTATION(7, 18, 3, 17, 19, 10, 6, 11, 25, 2, 13, 22, uint32_t,
state->k.b32, state->w.b32, state->h.b32, state->work_h.b32);
#undef ROTR
#if defined(__GNUC__)
# pragma GCC diagnostic pop
#endif
}
/**
* Process a chunk using SHA-512
*
* @param state The hashing state
*/
#if defined(__GNUC__)
__attribute__((__nonnull__, __nothrow__))
#endif
static void
process512(struct libsha2_state *restrict state)
{
uint64_t s0, s1;
size_t i, j;
#define ROTR(X, N) (((X) >> (N)) | ((X) << ((sizeof(uint64_t) * 8) - (N))))
SHA2_IMPLEMENTATION(1, 8, 7, 19, 61, 6, 14, 18, 41, 28, 34, 39, uint64_t,
state->k.b64, state->w.b64, state->h.b64, state->work_h.b64);
#undef ROTR
}
/**
* Absorb more of the message
*
* @param state The hashing state
* @param message The message, in bits, must be equivalent to 0 modulus 8
* @param msglen The length of the message
*/
void
libsha2_update(struct libsha2_state *restrict state, const char *restrict message, size_t msglen)
{
size_t n, off, mlen;
msglen /= 8;
mlen = state->message_size / 8;
while (msglen) {
off = mlen % state->chunk_size;
n = state->chunk_size - off;
n = n < msglen ? n : msglen;
memcpy(state->chunk + off, message, n);
if (off + n == state->chunk_size) {
switch (state->algorithm) {
case LIBSHA2_224:
case LIBSHA2_256:
process256(state);
break;
default:
process512(state);
break;
}
}
message += n, mlen += n, msglen -= n;
}
state->message_size = mlen * 8;
}
