1 files changed, 82 insertions, 0 deletions
diff --git a/src/crypto/hash.c b/src/crypto/hash.c
new file mode 100644
index 000000000..f07ffd661
--- /dev/null
+++ b/src/crypto/hash.c
@@ -0,0 +1,82 @@
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "int-util.h"
+#include "hash.h"
+
+static const uint64_t round_constants[] = {
+  0x0000000000000001, 0x0000000000008082, 0x800000000000808a, 0x8000000080008000,
+  0x000000000000808b, 0x0000000080000001, 0x8000000080008081, 0x8000000000008009,
+  0x000000000000008a, 0x0000000000000088, 0x0000000080008009, 0x000000008000000a,
+  0x000000008000808b, 0x800000000000008b, 0x8000000000008089, 0x8000000000008003,
+  0x8000000000008002, 0x8000000000000080, 0x000000000000800a, 0x800000008000000a,
+  0x8000000080008081, 0x8000000000008080, 0x0000000080000001, 0x8000000080008008
+};
+
+static const uint8_t rho_offsets[] = {
+  0, 1, 62, 28, 27,
+  36, 44, 6, 55, 20,
+  3, 10, 43, 25, 39,
+  41, 45, 15, 21, 8,
+  18, 2, 61, 56, 14
+};
+
+static void keccak_round(uint64_t *state, unsigned int i) {
+  unsigned int j, k;
+  uint64_t tmp[25];
+  for(j = 0; j < 5; j++) {
+    tmp[j] = state[j] ^ state[j + 5] ^ state[j + 10] ^ state[j + 15] ^ state[j + 20];
+  }
+  for(j = 0; j < 5; j++) {
+    uint64_t t = rol64(tmp[(j + 1) % 5], 1) ^ tmp[(j + 4) % 5];
+    state[j] ^= t;
+    state[j + 5] ^= t;
+    state[j + 10] ^= t;
+    state[j + 15] ^= t;
+    state[j + 20] ^= t;
+  }
+  for(j = 0; j < 25; j++) {
+    state[j] = rol64(state[j], rho_offsets[j]);
+  }
+#define index(x, y) (((x) % 5) + 5 * ((y) % 5))
+  for(j = 0; j < 5; j++) {
+    for(k = 0; k < 5; k++) {
+      tmp[index(0 * k + 1 * j, 2 * k + 3 * j)] = state[index(k, j)];
+    }
+  }
+  for(j = 0; j < 5; j++) {
+    for(k = 0; k < 5; k++) {
+      state[index(k, j)] = tmp[index(k, j)] ^ ((~tmp[index(k + 1, j)]) & tmp[index(k + 2, j)]);
+    }
+  }
+#undef index
+  state[0] ^= round_constants[i];
+}
+
+void keccak_permutation(struct keccak_state *state) {
+  unsigned int i;
+  mem_inplace_swap64le(&state, 25);
+  for (i = 0; i < 24; i++) {
+    keccak_round(state->w, i);
+  }
+  mem_inplace_swap64le(&state, 25);
+}
+
+void keccak(const void *data, size_t length, char *hash) {
+  struct keccak_state state;
+  const void *limit = cpadd(data, length);
+  size_t i;
+  memset(&state, 0, sizeof(struct keccak_state));
+  for (i = 0; data != limit; ++data) {
+    state.b[i] ^= *(char *) data;
+    if (++i == 136) {
+      keccak_permutation(&state);
+      i = 0;
+    }
+  }
+  state.b[i] ^= 1;
+  state.b[135] ^= 0x80;
+  keccak_permutation(&state);
+  memcpy(hash, &state, 32);
+}
+\ No newline at end of file