3 /* Process LEN bytes of BUFFER, accumulating context into CTX.
4 It is assumed that LEN % 128 == 0. */
6 sha512_process_block (const void *buffer, size_t len, struct sha512_ctx *ctx)
8 const uint64_t *words = buffer;
9 size_t nwords = len / sizeof (uint64_t);
10 uint64_t a = ctx->H[0];
11 uint64_t b = ctx->H[1];
12 uint64_t c = ctx->H[2];
13 uint64_t d = ctx->H[3];
14 uint64_t e = ctx->H[4];
15 uint64_t f = ctx->H[5];
16 uint64_t g = ctx->H[6];
17 uint64_t h = ctx->H[7];
19 /* First increment the byte count. FIPS 180-2 specifies the possible
20 length of the file up to 2^128 bits. Here we only compute the
21 number of bytes. Do a double word increment. */
26 ctx->total[TOTAL128_low] += lolen;
27 ctx->total[TOTAL128_high] += ((len >> 31 >> 31 >> 2)
28 + (ctx->total[TOTAL128_low] < lolen));
31 /* Process all bytes in the buffer with 128 bytes in each round of
45 /* Operators defined in FIPS 180-2:4.1.2. */
46 #define Ch(x, y, z) ((x & y) ^ (~x & z))
47 #define Maj(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
48 #define S0(x) (CYCLIC (x, 28) ^ CYCLIC (x, 34) ^ CYCLIC (x, 39))
49 #define S1(x) (CYCLIC (x, 14) ^ CYCLIC (x, 18) ^ CYCLIC (x, 41))
50 #define R0(x) (CYCLIC (x, 1) ^ CYCLIC (x, 8) ^ (x >> 7))
51 #define R1(x) (CYCLIC (x, 19) ^ CYCLIC (x, 61) ^ (x >> 6))
53 /* It is unfortunate that C does not provide an operator for
54 cyclic rotation. Hope the C compiler is smart enough. */
55 #define CYCLIC(w, s) ((w >> s) | (w << (64 - s)))
57 /* Compute the message schedule according to FIPS 180-2:6.3.2 step 2. */
58 for (unsigned int t = 0; t < 16; ++t)
63 for (unsigned int t = 16; t < 80; ++t)
64 W[t] = R1 (W[t - 2]) + W[t - 7] + R0 (W[t - 15]) + W[t - 16];
66 /* The actual computation according to FIPS 180-2:6.3.2 step 3. */
67 for (unsigned int t = 0; t < 80; ++t)
69 uint64_t T1 = h + S1 (e) + Ch (e, f, g) + K[t] + W[t];
70 uint64_t T2 = S0 (a) + Maj (a, b, c);
81 /* Add the starting values of the context according to FIPS 180-2:6.3.2
92 /* Prepare for the next round. */
96 /* Put checksum in context given as argument. */