feat: add siphash24 implementation (#11)

* use SipHash from std

src/hashes/siphash24.zig

@@ -0,0 +1,183 @@
+const std = @import("std");
+const testing = std.testing;
+const mem = std.mem;
+const math = std.math;
+const assert = std.debug.assert;
+const SipHash64 = std.hash.SipHash64;
+const SipHash128 = std.hash.SipHash128;
+
+// Adapted from https://github.com/ziglang/zig/blob/master/lib/std/crypto/siphash.zig
+
+pub fn SipHash24(comptime T: type) type {
+    const c_rounds = 2;
+    const d_rounds = 4;
+    return switch (T) {
+        u64 => SipHash64(c_rounds, d_rounds),
+        u128 => SipHash128(c_rounds, d_rounds),
+        else => @compileError("Type must be u64 or u128, got " ++ @typeName(T)),
+    };
+}
+
+// Test vectors from reference implementation.
+// https://github.com/veorq/SipHash/blob/master/vectors.h
+const test_key = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f";
+
+test "siphash64-2-4 sanity" {
+    const vectors = [_][8]u8{
+        "\x31\x0e\x0e\xdd\x47\xdb\x6f\x72".*, // ""
+        "\xfd\x67\xdc\x93\xc5\x39\xf8\x74".*, // "\x00"
+        "\x5a\x4f\xa9\xd9\x09\x80\x6c\x0d".*, // "\x00\x01" ... etc
+        "\x2d\x7e\xfb\xd7\x96\x66\x67\x85".*,
+        "\xb7\x87\x71\x27\xe0\x94\x27\xcf".*,
+        "\x8d\xa6\x99\xcd\x64\x55\x76\x18".*,
+        "\xce\xe3\xfe\x58\x6e\x46\xc9\xcb".*,
+        "\x37\xd1\x01\x8b\xf5\x00\x02\xab".*,
+        "\x62\x24\x93\x9a\x79\xf5\xf5\x93".*,
+        "\xb0\xe4\xa9\x0b\xdf\x82\x00\x9e".*,
+        "\xf3\xb9\xdd\x94\xc5\xbb\x5d\x7a".*,
+        "\xa7\xad\x6b\x22\x46\x2f\xb3\xf4".*,
+        "\xfb\xe5\x0e\x86\xbc\x8f\x1e\x75".*,
+        "\x90\x3d\x84\xc0\x27\x56\xea\x14".*,
+        "\xee\xf2\x7a\x8e\x90\xca\x23\xf7".*,
+        "\xe5\x45\xbe\x49\x61\xca\x29\xa1".*,
+        "\xdb\x9b\xc2\x57\x7f\xcc\x2a\x3f".*,
+        "\x94\x47\xbe\x2c\xf5\xe9\x9a\x69".*,
+        "\x9c\xd3\x8d\x96\xf0\xb3\xc1\x4b".*,
+        "\xbd\x61\x79\xa7\x1d\xc9\x6d\xbb".*,
+        "\x98\xee\xa2\x1a\xf2\x5c\xd6\xbe".*,
+        "\xc7\x67\x3b\x2e\xb0\xcb\xf2\xd0".*,
+        "\x88\x3e\xa3\xe3\x95\x67\x53\x93".*,
+        "\xc8\xce\x5c\xcd\x8c\x03\x0c\xa8".*,
+        "\x94\xaf\x49\xf6\xc6\x50\xad\xb8".*,
+        "\xea\xb8\x85\x8a\xde\x92\xe1\xbc".*,
+        "\xf3\x15\xbb\x5b\xb8\x35\xd8\x17".*,
+        "\xad\xcf\x6b\x07\x63\x61\x2e\x2f".*,
+        "\xa5\xc9\x1d\xa7\xac\xaa\x4d\xde".*,
+        "\x71\x65\x95\x87\x66\x50\xa2\xa6".*,
+        "\x28\xef\x49\x5c\x53\xa3\x87\xad".*,
+        "\x42\xc3\x41\xd8\xfa\x92\xd8\x32".*,
+        "\xce\x7c\xf2\x72\x2f\x51\x27\x71".*,
+        "\xe3\x78\x59\xf9\x46\x23\xf3\xa7".*,
+        "\x38\x12\x05\xbb\x1a\xb0\xe0\x12".*,
+        "\xae\x97\xa1\x0f\xd4\x34\xe0\x15".*,
+        "\xb4\xa3\x15\x08\xbe\xff\x4d\x31".*,
+        "\x81\x39\x62\x29\xf0\x90\x79\x02".*,
+        "\x4d\x0c\xf4\x9e\xe5\xd4\xdc\xca".*,
+        "\x5c\x73\x33\x6a\x76\xd8\xbf\x9a".*,
+        "\xd0\xa7\x04\x53\x6b\xa9\x3e\x0e".*,
+        "\x92\x59\x58\xfc\xd6\x42\x0c\xad".*,
+        "\xa9\x15\xc2\x9b\xc8\x06\x73\x18".*,
+        "\x95\x2b\x79\xf3\xbc\x0a\xa6\xd4".*,
+        "\xf2\x1d\xf2\xe4\x1d\x45\x35\xf9".*,
+        "\x87\x57\x75\x19\x04\x8f\x53\xa9".*,
+        "\x10\xa5\x6c\xf5\xdf\xcd\x9a\xdb".*,
+        "\xeb\x75\x09\x5c\xcd\x98\x6c\xd0".*,
+        "\x51\xa9\xcb\x9e\xcb\xa3\x12\xe6".*,
+        "\x96\xaf\xad\xfc\x2c\xe6\x66\xc7".*,
+        "\x72\xfe\x52\x97\x5a\x43\x64\xee".*,
+        "\x5a\x16\x45\xb2\x76\xd5\x92\xa1".*,
+        "\xb2\x74\xcb\x8e\xbf\x87\x87\x0a".*,
+        "\x6f\x9b\xb4\x20\x3d\xe7\xb3\x81".*,
+        "\xea\xec\xb2\xa3\x0b\x22\xa8\x7f".*,
+        "\x99\x24\xa4\x3c\xc1\x31\x57\x24".*,
+        "\xbd\x83\x8d\x3a\xaf\xbf\x8d\xb7".*,
+        "\x0b\x1a\x2a\x32\x65\xd5\x1a\xea".*,
+        "\x13\x50\x79\xa3\x23\x1c\xe6\x60".*,
+        "\x93\x2b\x28\x46\xe4\xd7\x06\x66".*,
+        "\xe1\x91\x5f\x5c\xb1\xec\xa4\x6c".*,
+        "\xf3\x25\x96\x5c\xa1\x6d\x62\x9f".*,
+        "\x57\x5f\xf2\x8e\x60\x38\x1b\xe5".*,
+        "\x72\x45\x06\xeb\x4c\x32\x8a\x95".*,
+    };
+
+    const siphash = SipHash24(u64);
+
+    var buffer: [64]u8 = undefined;
+    for (vectors, 0..) |vector, i| {
+        buffer[i] = @as(u8, @intCast(i));
+
+        var out: [siphash.mac_length]u8 = undefined;
+        siphash.create(&out, buffer[0..i], test_key);
+        try testing.expectEqual(out, vector);
+    }
+}
+
+test "siphash128-2-4 sanity" {
+    const vectors = [_][16]u8{
+        "\xa3\x81\x7f\x04\xba\x25\xa8\xe6\x6d\xf6\x72\x14\xc7\x55\x02\x93".*,
+        "\xda\x87\xc1\xd8\x6b\x99\xaf\x44\x34\x76\x59\x11\x9b\x22\xfc\x45".*,
+        "\x81\x77\x22\x8d\xa4\xa4\x5d\xc7\xfc\xa3\x8b\xde\xf6\x0a\xff\xe4".*,
+        "\x9c\x70\xb6\x0c\x52\x67\xa9\x4e\x5f\x33\xb6\xb0\x29\x85\xed\x51".*,
+        "\xf8\x81\x64\xc1\x2d\x9c\x8f\xaf\x7d\x0f\x6e\x7c\x7b\xcd\x55\x79".*,
+        "\x13\x68\x87\x59\x80\x77\x6f\x88\x54\x52\x7a\x07\x69\x0e\x96\x27".*,
+        "\x14\xee\xca\x33\x8b\x20\x86\x13\x48\x5e\xa0\x30\x8f\xd7\xa1\x5e".*,
+        "\xa1\xf1\xeb\xbe\xd8\xdb\xc1\x53\xc0\xb8\x4a\xa6\x1f\xf0\x82\x39".*,
+        "\x3b\x62\xa9\xba\x62\x58\xf5\x61\x0f\x83\xe2\x64\xf3\x14\x97\xb4".*,
+        "\x26\x44\x99\x06\x0a\xd9\xba\xab\xc4\x7f\x8b\x02\xbb\x6d\x71\xed".*,
+        "\x00\x11\x0d\xc3\x78\x14\x69\x56\xc9\x54\x47\xd3\xf3\xd0\xfb\xba".*,
+        "\x01\x51\xc5\x68\x38\x6b\x66\x77\xa2\xb4\xdc\x6f\x81\xe5\xdc\x18".*,
+        "\xd6\x26\xb2\x66\x90\x5e\xf3\x58\x82\x63\x4d\xf6\x85\x32\xc1\x25".*,
+        "\x98\x69\xe2\x47\xe9\xc0\x8b\x10\xd0\x29\x93\x4f\xc4\xb9\x52\xf7".*,
+        "\x31\xfc\xef\xac\x66\xd7\xde\x9c\x7e\xc7\x48\x5f\xe4\x49\x49\x02".*,
+        "\x54\x93\xe9\x99\x33\xb0\xa8\x11\x7e\x08\xec\x0f\x97\xcf\xc3\xd9".*,
+        "\x6e\xe2\xa4\xca\x67\xb0\x54\xbb\xfd\x33\x15\xbf\x85\x23\x05\x77".*,
+        "\x47\x3d\x06\xe8\x73\x8d\xb8\x98\x54\xc0\x66\xc4\x7a\xe4\x77\x40".*,
+        "\xa4\x26\xe5\xe4\x23\xbf\x48\x85\x29\x4d\xa4\x81\xfe\xae\xf7\x23".*,
+        "\x78\x01\x77\x31\xcf\x65\xfa\xb0\x74\xd5\x20\x89\x52\x51\x2e\xb1".*,
+        "\x9e\x25\xfc\x83\x3f\x22\x90\x73\x3e\x93\x44\xa5\xe8\x38\x39\xeb".*,
+        "\x56\x8e\x49\x5a\xbe\x52\x5a\x21\x8a\x22\x14\xcd\x3e\x07\x1d\x12".*,
+        "\x4a\x29\xb5\x45\x52\xd1\x6b\x9a\x46\x9c\x10\x52\x8e\xff\x0a\xae".*,
+        "\xc9\xd1\x84\xdd\xd5\xa9\xf5\xe0\xcf\x8c\xe2\x9a\x9a\xbf\x69\x1c".*,
+        "\x2d\xb4\x79\xae\x78\xbd\x50\xd8\x88\x2a\x8a\x17\x8a\x61\x32\xad".*,
+        "\x8e\xce\x5f\x04\x2d\x5e\x44\x7b\x50\x51\xb9\xea\xcb\x8d\x8f\x6f".*,
+        "\x9c\x0b\x53\xb4\xb3\xc3\x07\xe8\x7e\xae\xe0\x86\x78\x14\x1f\x66".*,
+        "\xab\xf2\x48\xaf\x69\xa6\xea\xe4\xbf\xd3\xeb\x2f\x12\x9e\xeb\x94".*,
+        "\x06\x64\xda\x16\x68\x57\x4b\x88\xb9\x35\xf3\x02\x73\x58\xae\xf4".*,
+        "\xaa\x4b\x9d\xc4\xbf\x33\x7d\xe9\x0c\xd4\xfd\x3c\x46\x7c\x6a\xb7".*,
+        "\xea\x5c\x7f\x47\x1f\xaf\x6b\xde\x2b\x1a\xd7\xd4\x68\x6d\x22\x87".*,
+        "\x29\x39\xb0\x18\x32\x23\xfa\xfc\x17\x23\xde\x4f\x52\xc4\x3d\x35".*,
+        "\x7c\x39\x56\xca\x5e\xea\xfc\x3e\x36\x3e\x9d\x55\x65\x46\xeb\x68".*,
+        "\x77\xc6\x07\x71\x46\xf0\x1c\x32\xb6\xb6\x9d\x5f\x4e\xa9\xff\xcf".*,
+        "\x37\xa6\x98\x6c\xb8\x84\x7e\xdf\x09\x25\xf0\xf1\x30\x9b\x54\xde".*,
+        "\xa7\x05\xf0\xe6\x9d\xa9\xa8\xf9\x07\x24\x1a\x2e\x92\x3c\x8c\xc8".*,
+        "\x3d\xc4\x7d\x1f\x29\xc4\x48\x46\x1e\x9e\x76\xed\x90\x4f\x67\x11".*,
+        "\x0d\x62\xbf\x01\xe6\xfc\x0e\x1a\x0d\x3c\x47\x51\xc5\xd3\x69\x2b".*,
+        "\x8c\x03\x46\x8b\xca\x7c\x66\x9e\xe4\xfd\x5e\x08\x4b\xbe\xe7\xb5".*,
+        "\x52\x8a\x5b\xb9\x3b\xaf\x2c\x9c\x44\x73\xcc\xe5\xd0\xd2\x2b\xd9".*,
+        "\xdf\x6a\x30\x1e\x95\xc9\x5d\xad\x97\xae\x0c\xc8\xc6\x91\x3b\xd8".*,
+        "\x80\x11\x89\x90\x2c\x85\x7f\x39\xe7\x35\x91\x28\x5e\x70\xb6\xdb".*,
+        "\xe6\x17\x34\x6a\xc9\xc2\x31\xbb\x36\x50\xae\x34\xcc\xca\x0c\x5b".*,
+        "\x27\xd9\x34\x37\xef\xb7\x21\xaa\x40\x18\x21\xdc\xec\x5a\xdf\x89".*,
+        "\x89\x23\x7d\x9d\xed\x9c\x5e\x78\xd8\xb1\xc9\xb1\x66\xcc\x73\x42".*,
+        "\x4a\x6d\x80\x91\xbf\x5e\x7d\x65\x11\x89\xfa\x94\xa2\x50\xb1\x4c".*,
+        "\x0e\x33\xf9\x60\x55\xe7\xae\x89\x3f\xfc\x0e\x3d\xcf\x49\x29\x02".*,
+        "\xe6\x1c\x43\x2b\x72\x0b\x19\xd1\x8e\xc8\xd8\x4b\xdc\x63\x15\x1b".*,
+        "\xf7\xe5\xae\xf5\x49\xf7\x82\xcf\x37\x90\x55\xa6\x08\x26\x9b\x16".*,
+        "\x43\x8d\x03\x0f\xd0\xb7\xa5\x4f\xa8\x37\xf2\xad\x20\x1a\x64\x03".*,
+        "\xa5\x90\xd3\xee\x4f\xbf\x04\xe3\x24\x7e\x0d\x27\xf2\x86\x42\x3f".*,
+        "\x5f\xe2\xc1\xa1\x72\xfe\x93\xc4\xb1\x5c\xd3\x7c\xae\xf9\xf5\x38".*,
+        "\x2c\x97\x32\x5c\xbd\x06\xb3\x6e\xb2\x13\x3d\xd0\x8b\x3a\x01\x7c".*,
+        "\x92\xc8\x14\x22\x7a\x6b\xca\x94\x9f\xf0\x65\x9f\x00\x2a\xd3\x9e".*,
+        "\xdc\xe8\x50\x11\x0b\xd8\x32\x8c\xfb\xd5\x08\x41\xd6\x91\x1d\x87".*,
+        "\x67\xf1\x49\x84\xc7\xda\x79\x12\x48\xe3\x2b\xb5\x92\x25\x83\xda".*,
+        "\x19\x38\xf2\xcf\x72\xd5\x4e\xe9\x7e\x94\x16\x6f\xa9\x1d\x2a\x36".*,
+        "\x74\x48\x1e\x96\x46\xed\x49\xfe\x0f\x62\x24\x30\x16\x04\x69\x8e".*,
+        "\x57\xfc\xa5\xde\x98\xa9\xd6\xd8\x00\x64\x38\xd0\x58\x3d\x8a\x1d".*,
+        "\x9f\xec\xde\x1c\xef\xdc\x1c\xbe\xd4\x76\x36\x74\xd9\x57\x53\x59".*,
+        "\xe3\x04\x0c\x00\xeb\x28\xf1\x53\x66\xca\x73\xcb\xd8\x72\xe7\x40".*,
+        "\x76\x97\x00\x9a\x6a\x83\x1d\xfe\xcc\xa9\x1c\x59\x93\x67\x0f\x7a".*,
+        "\x58\x53\x54\x23\x21\xf5\x67\xa0\x05\xd5\x47\xa4\xf0\x47\x59\xbd".*,
+        "\x51\x50\xd1\x77\x2f\x50\x83\x4a\x50\x3e\x06\x9a\x97\x3f\xbd\x7c".*,
+    };
+
+    const siphash = SipHash24(u128);
+
+    var buffer: [64]u8 = undefined;
+    for (vectors, 0..) |vector, i| {
+        buffer[i] = @as(u8, @intCast(i));
+
+        var out: [siphash.mac_length]u8 = undefined;
+        siphash.create(&out, buffer[0..i], test_key[0..]);
+        try testing.expectEqual(out, vector);
+    }
+}