/* Functions to compute SHA512 message digest of files or memory blocks.
according to the definition of SHA512 in FIPS 180-2.
Copyright (C) 2007-2017 Free Software Foundation, Inc.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public License
as published by the Free Software Foundation; either version 2.1 of
the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see
<https://www.gnu.org/licenses/>. */
/* Written by Ulrich Drepper <drepper@redhat.com>, 2007. */
#include "crypt-port.h"
#include "alg-sha512.h"
#include "byteorder.h"
#if INCLUDE_sha512
/* Constants for SHA512 from FIPS 180-2:4.2.3. */
static const uint64_t K[80] =
{
UINT64_C (0x428a2f98d728ae22), UINT64_C (0x7137449123ef65cd),
UINT64_C (0xb5c0fbcfec4d3b2f), UINT64_C (0xe9b5dba58189dbbc),
UINT64_C (0x3956c25bf348b538), UINT64_C (0x59f111f1b605d019),
UINT64_C (0x923f82a4af194f9b), UINT64_C (0xab1c5ed5da6d8118),
UINT64_C (0xd807aa98a3030242), UINT64_C (0x12835b0145706fbe),
UINT64_C (0x243185be4ee4b28c), UINT64_C (0x550c7dc3d5ffb4e2),
UINT64_C (0x72be5d74f27b896f), UINT64_C (0x80deb1fe3b1696b1),
UINT64_C (0x9bdc06a725c71235), UINT64_C (0xc19bf174cf692694),
UINT64_C (0xe49b69c19ef14ad2), UINT64_C (0xefbe4786384f25e3),
UINT64_C (0x0fc19dc68b8cd5b5), UINT64_C (0x240ca1cc77ac9c65),
UINT64_C (0x2de92c6f592b0275), UINT64_C (0x4a7484aa6ea6e483),
UINT64_C (0x5cb0a9dcbd41fbd4), UINT64_C (0x76f988da831153b5),
UINT64_C (0x983e5152ee66dfab), UINT64_C (0xa831c66d2db43210),
UINT64_C (0xb00327c898fb213f), UINT64_C (0xbf597fc7beef0ee4),
UINT64_C (0xc6e00bf33da88fc2), UINT64_C (0xd5a79147930aa725),
UINT64_C (0x06ca6351e003826f), UINT64_C (0x142929670a0e6e70),
UINT64_C (0x27b70a8546d22ffc), UINT64_C (0x2e1b21385c26c926),
UINT64_C (0x4d2c6dfc5ac42aed), UINT64_C (0x53380d139d95b3df),
UINT64_C (0x650a73548baf63de), UINT64_C (0x766a0abb3c77b2a8),
UINT64_C (0x81c2c92e47edaee6), UINT64_C (0x92722c851482353b),
UINT64_C (0xa2bfe8a14cf10364), UINT64_C (0xa81a664bbc423001),
UINT64_C (0xc24b8b70d0f89791), UINT64_C (0xc76c51a30654be30),
UINT64_C (0xd192e819d6ef5218), UINT64_C (0xd69906245565a910),
UINT64_C (0xf40e35855771202a), UINT64_C (0x106aa07032bbd1b8),
UINT64_C (0x19a4c116b8d2d0c8), UINT64_C (0x1e376c085141ab53),
UINT64_C (0x2748774cdf8eeb99), UINT64_C (0x34b0bcb5e19b48a8),
UINT64_C (0x391c0cb3c5c95a63), UINT64_C (0x4ed8aa4ae3418acb),
UINT64_C (0x5b9cca4f7763e373), UINT64_C (0x682e6ff3d6b2b8a3),
UINT64_C (0x748f82ee5defb2fc), UINT64_C (0x78a5636f43172f60),
UINT64_C (0x84c87814a1f0ab72), UINT64_C (0x8cc702081a6439ec),
UINT64_C (0x90befffa23631e28), UINT64_C (0xa4506cebde82bde9),
UINT64_C (0xbef9a3f7b2c67915), UINT64_C (0xc67178f2e372532b),
UINT64_C (0xca273eceea26619c), UINT64_C (0xd186b8c721c0c207),
UINT64_C (0xeada7dd6cde0eb1e), UINT64_C (0xf57d4f7fee6ed178),
UINT64_C (0x06f067aa72176fba), UINT64_C (0x0a637dc5a2c898a6),
UINT64_C (0x113f9804bef90dae), UINT64_C (0x1b710b35131c471b),
UINT64_C (0x28db77f523047d84), UINT64_C (0x32caab7b40c72493),
UINT64_C (0x3c9ebe0a15c9bebc), UINT64_C (0x431d67c49c100d4c),
UINT64_C (0x4cc5d4becb3e42b6), UINT64_C (0x597f299cfc657e2a),
UINT64_C (0x5fcb6fab3ad6faec), UINT64_C (0x6c44198c4a475817)
};
/* Process LEN bytes of BUFFER, accumulating context into CTX.
It is assumed that LEN % 128 == 0. */
static void
sha512_process_block (const void *buffer, size_t len, struct sha512_ctx *ctx)
{
unsigned int t;
const unsigned char *p = buffer;
size_t nwords = len / sizeof (uint64_t);
uint64_t a = ctx->H[0];
uint64_t b = ctx->H[1];
uint64_t c = ctx->H[2];
uint64_t d = ctx->H[3];
uint64_t e = ctx->H[4];
uint64_t f = ctx->H[5];
uint64_t g = ctx->H[6];
uint64_t h = ctx->H[7];
/* First increment the byte count. FIPS 180-2 specifies the possible
length of the file up to 2^128 bits. Here we only compute the
number of bytes. Do a double word increment. */
ctx->total[0] += len;
if (ctx->total[0] < len)
++ctx->total[1];
/* Process all bytes in the buffer with 128 bytes in each round of
the loop. */
while (nwords > 0)
{
uint64_t W[80];
uint64_t a_save = a;
uint64_t b_save = b;
uint64_t c_save = c;
uint64_t d_save = d;
uint64_t e_save = e;
uint64_t f_save = f;
uint64_t g_save = g;
uint64_t h_save = h;
/* Operators defined in FIPS 180-2:4.1.2. */
#define Ch(x, y, z) ((x & y) ^ (~x & z))
#define Maj(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
#define S0(x) (CYCLIC (x, 28) ^ CYCLIC (x, 34) ^ CYCLIC (x, 39))
#define S1(x) (CYCLIC (x, 14) ^ CYCLIC (x, 18) ^ CYCLIC (x, 41))
#define R0(x) (CYCLIC (x, 1) ^ CYCLIC (x, 8) ^ (x >> 7))
#define R1(x) (CYCLIC (x, 19) ^ CYCLIC (x, 61) ^ (x >> 6))
/* It is unfortunate that C does not provide an operator for
cyclic rotation. Hope the C compiler is smart enough. */
#define CYCLIC(w, s) ((w >> s) | (w << (64 - s)))
/* Compute the message schedule according to FIPS 180-2:6.3.2 step 2. */
for (t = 0; t < 16; ++t)
{
W[t] = be64_to_cpu (p);
p += 8;
}
for (t = 16; t < 80; ++t)
W[t] = R1 (W[t - 2]) + W[t - 7] + R0 (W[t - 15]) + W[t - 16];
/* The actual computation according to FIPS 180-2:6.3.2 step 3. */
for (t = 0; t < 80; ++t)
{
uint64_t T1 = h + S1 (e) + Ch (e, f, g) + K[t] + W[t];
uint64_t T2 = S0 (a) + Maj (a, b, c);
h = g;
g = f;
f = e;
e = d + T1;
d = c;
c = b;
b = a;
a = T1 + T2;
}
/* Add the starting values of the context according to FIPS 180-2:6.3.2
step 4. */
a += a_save;
b += b_save;
c += c_save;
d += d_save;
e += e_save;
f += f_save;
g += g_save;
h += h_save;
/* Prepare for the next round. */
nwords -= 16;
}
/* Put checksum in context given as argument. */
ctx->H[0] = a;
ctx->H[1] = b;
ctx->H[2] = c;
ctx->H[3] = d;
ctx->H[4] = e;
ctx->H[5] = f;
ctx->H[6] = g;
ctx->H[7] = h;
}
/* Initialize structure containing state of computation.
(FIPS 180-2:5.3.3) */
void
sha512_init_ctx (struct sha512_ctx *ctx)
{
ctx->H[0] = UINT64_C (0x6a09e667f3bcc908);
ctx->H[1] = UINT64_C (0xbb67ae8584caa73b);
ctx->H[2] = UINT64_C (0x3c6ef372fe94f82b);
ctx->H[3] = UINT64_C (0xa54ff53a5f1d36f1);
ctx->H[4] = UINT64_C (0x510e527fade682d1);
ctx->H[5] = UINT64_C (0x9b05688c2b3e6c1f);
ctx->H[6] = UINT64_C (0x1f83d9abfb41bd6b);
ctx->H[7] = UINT64_C (0x5be0cd19137e2179);
ctx->total[0] = ctx->total[1] = 0;
ctx->buflen = 0;
}
/* Process the remaining bytes in the internal buffer and the usual
prolog according to the standard and write the result to RESBUF.
IMPORTANT: On some systems it is required that RESBUF is correctly
aligned for a 32 bits value. */
void *
sha512_finish_ctx (struct sha512_ctx *ctx, void *resbuf)
{
/* Take yet unprocessed bytes into account. */
uint32_t bytes = ctx->buflen;
size_t pad;
unsigned int i;
unsigned char *rp = resbuf;
/* Now count remaining bytes. */
ctx->total[0] += bytes;
if (ctx->total[0] < bytes)
++ctx->total[1];
pad = bytes >= 112 ? 128 + 112 - bytes : 112 - bytes;
/* The first byte of padding should be 0x80 and the rest should be
zero. (FIPS 180-2:5.1.2) */
ctx->buffer[bytes] = 0x80u;
XCRYPT_SECURE_MEMSET (&ctx->buffer[bytes+1], pad-1);
/* Put the 128-bit file length in big-endian *bits* at the end of
the buffer. */
cpu_to_be64 (&ctx->buffer[bytes + pad],
(ctx->total[1] << 3) | (ctx->total[0] >> 61));
cpu_to_be64 (&ctx->buffer[bytes + pad + 8],
ctx->total[0] << 3);
/* Process last bytes. */
sha512_process_block (ctx->buffer, bytes + pad + 16, ctx);
/* Put result from CTX in first 64 bytes following RESBUF. */
for (i = 0; i < 8; ++i)
cpu_to_be64 (rp + i*8, ctx->H[i]);
XCRYPT_SECURE_MEMSET (ctx, sizeof (struct sha512_ctx));
return resbuf;
}
void
sha512_process_bytes (const void *buffer, size_t len, struct sha512_ctx *ctx)
{
/* When we already have some bits in our internal buffer concatenate
both inputs first. */
if (ctx->buflen != 0)
{
uint32_t left_over = ctx->buflen;
uint32_t add = 256 - left_over > len ? (uint32_t)len : 256 - left_over;
memcpy (&ctx->buffer[left_over], buffer, add);
ctx->buflen += add;
if (ctx->buflen > 128)
{
sha512_process_block (ctx->buffer, ctx->buflen & ~127u, ctx);
ctx->buflen &= 127;
/* The regions in the following copy operation cannot overlap. */
memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~127u],
ctx->buflen);
}
buffer = (const char *) buffer + add;
len -= add;
}
/* Process available complete blocks. */
if (len > 128)
{
sha512_process_block (buffer, len & ~127u, ctx);
buffer = (const char *) buffer + (len & ~127u);
len &= 127;
}
/* Move remaining bytes into internal buffer. */
if (len > 0)
{
size_t left_over = ctx->buflen;
memcpy (&ctx->buffer[left_over], buffer, len);
left_over += len;
if (left_over >= 128)
{
sha512_process_block (ctx->buffer, 128, ctx);
left_over -= 128;
memcpy (ctx->buffer, &ctx->buffer[128], left_over);
}
ctx->buflen = (uint32_t)left_over;
}
}
#endif