zig/lib/std/hash/siphash.zig
2019-11-08 15:57:24 -05:00

384 lines
15 KiB
Zig

// Siphash
//
// SipHash is a moderately fast, non-cryptographic keyed hash function designed for resistance
// against hash flooding DoS attacks.
//
// https://131002.net/siphash/
const std = @import("../std.zig");
const assert = std.debug.assert;
const testing = std.testing;
const math = std.math;
const mem = std.mem;
const Endian = @import("builtin").Endian;
pub fn SipHash64(comptime c_rounds: usize, comptime d_rounds: usize) type {
return SipHash(u64, c_rounds, d_rounds);
}
pub fn SipHash128(comptime c_rounds: usize, comptime d_rounds: usize) type {
return SipHash(u128, c_rounds, d_rounds);
}
fn SipHashStateless(comptime T: type, comptime c_rounds: usize, comptime d_rounds: usize) type {
assert(T == u64 or T == u128);
assert(c_rounds > 0 and d_rounds > 0);
return struct {
const Self = @This();
const digest_size = 64;
const block_size = 64;
v0: u64,
v1: u64,
v2: u64,
v3: u64,
msg_len: u8,
pub fn init(key: []const u8) Self {
assert(key.len >= 16);
const k0 = mem.readIntSliceLittle(u64, key[0..8]);
const k1 = mem.readIntSliceLittle(u64, key[8..16]);
var d = Self{
.v0 = k0 ^ 0x736f6d6570736575,
.v1 = k1 ^ 0x646f72616e646f6d,
.v2 = k0 ^ 0x6c7967656e657261,
.v3 = k1 ^ 0x7465646279746573,
.msg_len = 0,
};
if (T == u128) {
d.v1 ^= 0xee;
}
return d;
}
pub fn update(self: *Self, b: []const u8) void {
std.debug.assert(b.len % 8 == 0);
var off: usize = 0;
while (off < b.len) : (off += 8) {
@inlineCall(self.round, b[off .. off + 8]);
}
self.msg_len +%= @truncate(u8, b.len);
}
pub fn final(self: *Self, b: []const u8) T {
std.debug.assert(b.len < 8);
self.msg_len +%= @truncate(u8, b.len);
var buf = [_]u8{0} ** 8;
mem.copy(u8, buf[0..], b[0..]);
buf[7] = self.msg_len;
self.round(buf[0..]);
if (T == u128) {
self.v2 ^= 0xee;
} else {
self.v2 ^= 0xff;
}
comptime var i: usize = 0;
inline while (i < d_rounds) : (i += 1) {
@inlineCall(sipRound, self);
}
const b1 = self.v0 ^ self.v1 ^ self.v2 ^ self.v3;
if (T == u64) {
return b1;
}
self.v1 ^= 0xdd;
comptime var j: usize = 0;
inline while (j < d_rounds) : (j += 1) {
@inlineCall(sipRound, self);
}
const b2 = self.v0 ^ self.v1 ^ self.v2 ^ self.v3;
return (@as(u128, b2) << 64) | b1;
}
fn round(self: *Self, b: []const u8) void {
assert(b.len == 8);
const m = mem.readIntSliceLittle(u64, b[0..]);
self.v3 ^= m;
comptime var i: usize = 0;
inline while (i < c_rounds) : (i += 1) {
@inlineCall(sipRound, self);
}
self.v0 ^= m;
}
fn sipRound(d: *Self) void {
d.v0 +%= d.v1;
d.v1 = math.rotl(u64, d.v1, @as(u64, 13));
d.v1 ^= d.v0;
d.v0 = math.rotl(u64, d.v0, @as(u64, 32));
d.v2 +%= d.v3;
d.v3 = math.rotl(u64, d.v3, @as(u64, 16));
d.v3 ^= d.v2;
d.v0 +%= d.v3;
d.v3 = math.rotl(u64, d.v3, @as(u64, 21));
d.v3 ^= d.v0;
d.v2 +%= d.v1;
d.v1 = math.rotl(u64, d.v1, @as(u64, 17));
d.v1 ^= d.v2;
d.v2 = math.rotl(u64, d.v2, @as(u64, 32));
}
pub fn hash(key: []const u8, input: []const u8) T {
const aligned_len = input.len - (input.len % 8);
var c = Self.init(key);
@inlineCall(c.update, input[0..aligned_len]);
return @inlineCall(c.final, input[aligned_len..]);
}
};
}
pub fn SipHash(comptime T: type, comptime c_rounds: usize, comptime d_rounds: usize) type {
assert(T == u64 or T == u128);
assert(c_rounds > 0 and d_rounds > 0);
return struct {
const State = SipHashStateless(T, c_rounds, d_rounds);
const Self = @This();
const digest_size = 64;
const block_size = 64;
state: State,
buf: [8]u8,
buf_len: usize,
pub fn init(key: []const u8) Self {
return Self{
.state = State.init(key),
.buf = undefined,
.buf_len = 0,
};
}
pub fn update(self: *Self, b: []const u8) void {
var off: usize = 0;
if (self.buf_len != 0 and self.buf_len + b.len >= 8) {
off += 8 - self.buf_len;
mem.copy(u8, self.buf[self.buf_len..], b[0..off]);
self.state.update(self.buf[0..]);
self.buf_len = 0;
}
const remain_len = b.len - off;
const aligned_len = remain_len - (remain_len % 8);
self.state.update(b[off .. off + aligned_len]);
mem.copy(u8, self.buf[self.buf_len..], b[off + aligned_len ..]);
self.buf_len += @intCast(u8, b[off + aligned_len ..].len);
}
pub fn final(self: *Self) T {
return self.state.final(self.buf[0..self.buf_len]);
}
pub fn hash(key: []const u8, input: []const u8) T {
return State.hash(key, input);
}
};
}
// 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 = SipHash64(2, 4);
var buffer: [64]u8 = undefined;
for (vectors) |vector, i| {
buffer[i] = @intCast(u8, i);
const expected = mem.readIntLittle(u64, &vector);
testing.expectEqual(siphash.hash(test_key, buffer[0..i]), expected);
}
}
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 = SipHash128(2, 4);
var buffer: [64]u8 = undefined;
for (vectors) |vector, i| {
buffer[i] = @intCast(u8, i);
const expected = mem.readIntLittle(u128, &vector);
testing.expectEqual(siphash.hash(test_key, buffer[0..i]), expected);
}
}
test "iterative non-divisible update" {
var buf: [1024]u8 = undefined;
for (buf) |*e, i| {
e.* = @truncate(u8, i);
}
const key = "0x128dad08f12307";
const Siphash = SipHash64(2, 4);
var end: usize = 9;
while (end < buf.len) : (end += 9) {
const non_iterative_hash = Siphash.hash(key, buf[0..end]);
var wy = Siphash.init(key);
var i: usize = 0;
while (i < end) : (i += 7) {
wy.update(buf[i..std.math.min(i + 7, end)]);
}
const iterative_hash = wy.final();
std.testing.expectEqual(iterative_hash, non_iterative_hash);
}
}