Add wg2nd-web sourceHEADmain

1 files changed, 166 insertions, 0 deletions

diff --git a/src/models/crypto/halfsiphash.c b/src/models/crypto/halfsiphash.c
new file mode 100644
index 0000000..455c27c
--- /dev/null
+++ b/src/models/crypto/halfsiphash.c
@@ -0,0 +1,166 @@
+
+/*
+   SipHash reference C implementation
+
+   Copyright (c) 2016 Jean-Philippe Aumasson <jeanphilippe.aumasson@gmail.com>
+
+   To the extent possible under law, the author(s) have dedicated all copyright
+   and related and neighboring rights to this software to the public domain
+   worldwide. This software is distributed without any warranty.
+
+   You should have received a copy of the CC0 Public Domain Dedication along
+   with
+   this software. If not, see
+   <http://creativecommons.org/publicdomain/zero/1.0/>.
+ */
+#include "halfsiphash.h"
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+
+/* default: SipHash-2-4 */
+#ifndef cROUNDS
+#define cROUNDS 2
+#endif
+#ifndef dROUNDS
+#define dROUNDS 4
+#endif
+
+#define ROTL(x, b) (uint32_t)(((x) << (b)) | ((x) >> (32 - (b))))
+
+#define U32TO8_LE(p, v)                                                        \
+    (p)[0] = (uint8_t)((v));                                                   \
+    (p)[1] = (uint8_t)((v) >> 8);                                              \
+    (p)[2] = (uint8_t)((v) >> 16);                                             \
+    (p)[3] = (uint8_t)((v) >> 24);
+
+#define U8TO32_LE(p)                                                           \
+    (((uint32_t)((p)[0])) | ((uint32_t)((p)[1]) << 8) |                        \
+     ((uint32_t)((p)[2]) << 16) | ((uint32_t)((p)[3]) << 24))
+
+#define SIPROUND                                                               \
+    do {                                                                       \
+        v0 += v1;                                                              \
+        v1 = ROTL(v1, 5);                                                      \
+        v1 ^= v0;                                                              \
+        v0 = ROTL(v0, 16);                                                     \
+        v2 += v3;                                                              \
+        v3 = ROTL(v3, 8);                                                      \
+        v3 ^= v2;                                                              \
+        v0 += v3;                                                              \
+        v3 = ROTL(v3, 7);                                                      \
+        v3 ^= v0;                                                              \
+        v2 += v1;                                                              \
+        v1 = ROTL(v1, 13);                                                     \
+        v1 ^= v2;                                                              \
+        v2 = ROTL(v2, 16);                                                     \
+    } while (0)
+
+
+#ifdef DEBUG_SIPHASH
+#include <stdio.h>
+
+#define TRACE                                                                  \
+    do {                                                                       \
+        printf("(%3zu) v0 %08" PRIx32 "\n", inlen, v0);                        \
+        printf("(%3zu) v1 %08" PRIx32 "\n", inlen, v1);                        \
+        printf("(%3zu) v2 %08" PRIx32 "\n", inlen, v2);                        \
+        printf("(%3zu) v3 %08" PRIx32 "\n", inlen, v3);                        \
+    } while (0)
+#else
+#define TRACE
+#endif
+
+/*
+    Computes a SipHash value
+    *in: pointer to input data (read-only)
+    inlen: input data length in bytes (any size_t value)
+    *k: pointer to the key data (read-only), must be 8 bytes 
+    *out: pointer to output data (write-only), outlen bytes must be allocated
+    outlen: length of the output in bytes, must be 4 or 8
+*/
+int halfsiphash(const void *in, const size_t inlen, const void *k, uint8_t *out,
+                const size_t outlen) {
+
+    const unsigned char *ni = (const unsigned char *)in;
+    const unsigned char *kk = (const unsigned char *)k;
+
+    assert((outlen == 4) || (outlen == 8));
+    uint32_t v0 = 0;
+    uint32_t v1 = 0;
+    uint32_t v2 = UINT32_C(0x6c796765);
+    uint32_t v3 = UINT32_C(0x74656462);
+    uint32_t k0 = U8TO32_LE(kk);
+    uint32_t k1 = U8TO32_LE(kk + 4);
+    uint32_t m;
+    int i;
+    const unsigned char *end = ni + inlen - (inlen % sizeof(uint32_t));
+    const int left = inlen & 3;
+    uint32_t b = ((uint32_t)inlen) << 24;
+    v3 ^= k1;
+    v2 ^= k0;
+    v1 ^= k1;
+    v0 ^= k0;
+
+    if (outlen == 8)
+        v1 ^= 0xee;
+
+    for (; ni != end; ni += 4) {
+        m = U8TO32_LE(ni);
+        v3 ^= m;
+
+        TRACE;
+        for (i = 0; i < cROUNDS; ++i)
+            SIPROUND;
+
+        v0 ^= m;
+    }
+
+    switch (left) {
+    case 3:
+        b |= ((uint32_t)ni[2]) << 16;
+        /* FALLTHRU */
+    case 2:
+        b |= ((uint32_t)ni[1]) << 8;
+        /* FALLTHRU */
+    case 1:
+        b |= ((uint32_t)ni[0]);
+        break;
+    case 0:
+        break;
+    }
+
+    v3 ^= b;
+
+    TRACE;
+    for (i = 0; i < cROUNDS; ++i)
+        SIPROUND;
+
+    v0 ^= b;
+
+    if (outlen == 8)
+        v2 ^= 0xee;
+    else
+        v2 ^= 0xff;
+
+    TRACE;
+    for (i = 0; i < dROUNDS; ++i)
+        SIPROUND;
+
+    b = v1 ^ v3;
+    U32TO8_LE(out, b);
+
+    if (outlen == 4)
+        return 0;
+
+    v1 ^= 0xdd;
+
+    TRACE;
+    for (i = 0; i < dROUNDS; ++i)
+        SIPROUND;
+
+    b = v1 ^ v3;
+    U32TO8_LE(out + 4, b);
+
+    return 0;
+}