feature. See also
. The project being documented here (as the example) is the Zig library itself.
sha2.Sha2x32
fn Sha2x32(comptime iv: Iv32, digest_bits: comptime_int) type
File
Code
fn Sha2x32(comptime iv: Iv32, digest_bits: comptime_int) type {
return struct {
const Self = @This();
pub const block_length = 64;
pub const digest_length = digest_bits / 8;
pub const Options = struct {};
s: [8]u32 align(16),
buf: [64]u8 = undefined,
buf_len: u8 = 0,
total_len: u64 = 0,
pub fn init(options: Options) Self {
_ = options;
return Self{ .s = iv };
}
pub fn hash(b: []const u8, out: *[digest_length]u8, options: Options) void {
var d = Self.init(options);
d.update(b);
d.final(out);
}
pub fn update(d: *Self, b: []const u8) void {
var off: usize = 0;
if (d.buf_len != 0 and d.buf_len + b.len >= 64) {
off += 64 - d.buf_len;
@memcpy(d.buf[d.buf_len..][0..off], b[0..off]);
d.round(&d.buf);
d.buf_len = 0;
}
while (off + 64 <= b.len) : (off += 64) {
d.round(b[off..][0..64]);
}
const b_slice = b[off..];
@memcpy(d.buf[d.buf_len..][0..b_slice.len], b_slice);
d.buf_len += @as(u8, @intCast(b[off..].len));
d.total_len += b.len;
}
pub fn peek(d: Self) [digest_length]u8 {
var copy = d;
return copy.finalResult();
}
pub fn final(d: *Self, out: *[digest_length]u8) void {
@memset(d.buf[d.buf_len..], 0);
d.buf[d.buf_len] = 0x80;
d.buf_len += 1;
if (64 - d.buf_len < 8) {
d.round(&d.buf);
@memset(d.buf[0..], 0);
}
var i: usize = 1;
var len = d.total_len >> 5;
d.buf[63] = @as(u8, @intCast(d.total_len & 0x1f)) << 3;
while (i < 8) : (i += 1) {
d.buf[63 - i] = @as(u8, @intCast(len & 0xff));
len >>= 8;
}
d.round(&d.buf);
const rr = d.s[0 .. digest_length / 4];
for (rr, 0..) |s, j| {
mem.writeInt(u32, out[4 * j ..][0..4], s, .big);
}
}
pub fn finalResult(d: *Self) [digest_length]u8 {
var result: [digest_length]u8 = undefined;
d.final(&result);
return result;
}
const W = [64]u32{
0x428A2F98, 0x71374491, 0xB5C0FBCF, 0xE9B5DBA5, 0x3956C25B, 0x59F111F1, 0x923F82A4, 0xAB1C5ED5,
0xD807AA98, 0x12835B01, 0x243185BE, 0x550C7DC3, 0x72BE5D74, 0x80DEB1FE, 0x9BDC06A7, 0xC19BF174,
0xE49B69C1, 0xEFBE4786, 0x0FC19DC6, 0x240CA1CC, 0x2DE92C6F, 0x4A7484AA, 0x5CB0A9DC, 0x76F988DA,
0x983E5152, 0xA831C66D, 0xB00327C8, 0xBF597FC7, 0xC6E00BF3, 0xD5A79147, 0x06CA6351, 0x14292967,
0x27B70A85, 0x2E1B2138, 0x4D2C6DFC, 0x53380D13, 0x650A7354, 0x766A0ABB, 0x81C2C92E, 0x92722C85,
0xA2BFE8A1, 0xA81A664B, 0xC24B8B70, 0xC76C51A3, 0xD192E819, 0xD6990624, 0xF40E3585, 0x106AA070,
0x19A4C116, 0x1E376C08, 0x2748774C, 0x34B0BCB5, 0x391C0CB3, 0x4ED8AA4A, 0x5B9CCA4F, 0x682E6FF3,
0x748F82EE, 0x78A5636F, 0x84C87814, 0x8CC70208, 0x90BEFFFA, 0xA4506CEB, 0xBEF9A3F7, 0xC67178F2,
};
fn round(d: *Self, b: *const [64]u8) void {
var s: [64]u32 align(16) = undefined;
for (@as(*align(1) const [16]u32, @ptrCast(b)), 0..) |*elem, i| {
s[i] = mem.readInt(u32, mem.asBytes(elem), .big);
}
if (!@inComptime()) {
const V4u32 = @Vector(4, u32);
switch (builtin.cpu.arch) {
.aarch64 => if (builtin.zig_backend != .stage2_c and comptime builtin.cpu.has(.aarch64, .sha2)) {
var x: V4u32 = d.s[0..4].*;
var y: V4u32 = d.s[4..8].*;
const s_v = @as(*[16]V4u32, @ptrCast(&s));
comptime var k: u8 = 0;
inline while (k < 16) : (k += 1) {
if (k > 3) {
s_v[k] = asm (
\\sha256su0.4s %[w0_3], %[w4_7]
\\sha256su1.4s %[w0_3], %[w8_11], %[w12_15]
: [w0_3] "=&w" (-> V4u32),
: [_] "0" (s_v[k - 4]),
[w4_7] "w" (s_v[k - 3]),
[w8_11] "w" (s_v[k - 2]),
[w12_15] "w" (s_v[k - 1]),
);
}
const w: V4u32 = s_v[k] +% @as(V4u32, W[4 * k ..][0..4].*);
asm volatile (
\\mov.4s v0, %[x]
\\sha256h.4s %[x], %[y], %[w]
\\sha256h2.4s %[y], v0, %[w]
: [x] "=w" (x),
[y] "=w" (y),
: [_] "0" (x),
[_] "1" (y),
[w] "w" (w),
: .{ .v0 = true });
}
d.s[0..4].* = x +% @as(V4u32, d.s[0..4].*);
d.s[4..8].* = y +% @as(V4u32, d.s[4..8].*);
return;
},
.x86_64 => if (builtin.zig_backend != .stage2_c and comptime builtin.cpu.hasAll(.x86, &.{ .sha, .avx2 })) {
var x: V4u32 = [_]u32{ d.s[5], d.s[4], d.s[1], d.s[0] };
var y: V4u32 = [_]u32{ d.s[7], d.s[6], d.s[3], d.s[2] };
const s_v = @as(*[16]V4u32, @ptrCast(&s));
comptime var k: u8 = 0;
inline while (k < 16) : (k += 1) {
if (k < 12) {
var tmp = s_v[k];
s_v[k + 4] = asm (
\\ sha256msg1 %[w4_7], %[tmp]
\\ vpalignr $0x4, %[w8_11], %[w12_15], %[result]
\\ paddd %[tmp], %[result]
\\ sha256msg2 %[w12_15], %[result]
: [tmp] "=&x" (tmp),
[result] "=&x" (-> V4u32),
: [_] "0" (tmp),
[w4_7] "x" (s_v[k + 1]),
[w8_11] "x" (s_v[k + 2]),
[w12_15] "x" (s_v[k + 3]),
);
}
const w: V4u32 = s_v[k] +% @as(V4u32, W[4 * k ..][0..4].*);
y = asm ("sha256rnds2 %[x], %[y]"
: [y] "=x" (-> V4u32),
: [_] "0" (y),
[x] "x" (x),
[_] "{xmm0}" (w),
);
x = asm ("sha256rnds2 %[y], %[x]"
: [x] "=x" (-> V4u32),
: [_] "0" (x),
[y] "x" (y),
[_] "{xmm0}" (@as(V4u32, @bitCast(@as(u128, @bitCast(w)) >> 64))),
);
}
d.s[0] +%= x[3];
d.s[1] +%= x[2];
d.s[4] +%= x[1];
d.s[5] +%= x[0];
d.s[2] +%= y[3];
d.s[3] +%= y[2];
d.s[6] +%= y[1];
d.s[7] +%= y[0];
return;
},
else => {},
}
}
var i: usize = 16;
while (i < 64) : (i += 1) {
s[i] = s[i - 16] +% s[i - 7] +% (math.rotr(u32, s[i - 15], @as(u32, 7)) ^ math.rotr(u32, s[i - 15], @as(u32, 18)) ^ (s[i - 15] >> 3)) +% (math.rotr(u32, s[i - 2], @as(u32, 17)) ^ math.rotr(u32, s[i - 2], @as(u32, 19)) ^ (s[i - 2] >> 10));
}
var v: [8]u32 = d.s;
const round0 = comptime [_]RoundParam256{
roundParam256(0, 1, 2, 3, 4, 5, 6, 7, 0),
roundParam256(7, 0, 1, 2, 3, 4, 5, 6, 1),
roundParam256(6, 7, 0, 1, 2, 3, 4, 5, 2),
roundParam256(5, 6, 7, 0, 1, 2, 3, 4, 3),
roundParam256(4, 5, 6, 7, 0, 1, 2, 3, 4),
roundParam256(3, 4, 5, 6, 7, 0, 1, 2, 5),
roundParam256(2, 3, 4, 5, 6, 7, 0, 1, 6),
roundParam256(1, 2, 3, 4, 5, 6, 7, 0, 7),
roundParam256(0, 1, 2, 3, 4, 5, 6, 7, 8),
roundParam256(7, 0, 1, 2, 3, 4, 5, 6, 9),
roundParam256(6, 7, 0, 1, 2, 3, 4, 5, 10),
roundParam256(5, 6, 7, 0, 1, 2, 3, 4, 11),
roundParam256(4, 5, 6, 7, 0, 1, 2, 3, 12),
roundParam256(3, 4, 5, 6, 7, 0, 1, 2, 13),
roundParam256(2, 3, 4, 5, 6, 7, 0, 1, 14),
roundParam256(1, 2, 3, 4, 5, 6, 7, 0, 15),
roundParam256(0, 1, 2, 3, 4, 5, 6, 7, 16),
roundParam256(7, 0, 1, 2, 3, 4, 5, 6, 17),
roundParam256(6, 7, 0, 1, 2, 3, 4, 5, 18),
roundParam256(5, 6, 7, 0, 1, 2, 3, 4, 19),
roundParam256(4, 5, 6, 7, 0, 1, 2, 3, 20),
roundParam256(3, 4, 5, 6, 7, 0, 1, 2, 21),
roundParam256(2, 3, 4, 5, 6, 7, 0, 1, 22),
roundParam256(1, 2, 3, 4, 5, 6, 7, 0, 23),
roundParam256(0, 1, 2, 3, 4, 5, 6, 7, 24),
roundParam256(7, 0, 1, 2, 3, 4, 5, 6, 25),
roundParam256(6, 7, 0, 1, 2, 3, 4, 5, 26),
roundParam256(5, 6, 7, 0, 1, 2, 3, 4, 27),
roundParam256(4, 5, 6, 7, 0, 1, 2, 3, 28),
roundParam256(3, 4, 5, 6, 7, 0, 1, 2, 29),
roundParam256(2, 3, 4, 5, 6, 7, 0, 1, 30),
roundParam256(1, 2, 3, 4, 5, 6, 7, 0, 31),
roundParam256(0, 1, 2, 3, 4, 5, 6, 7, 32),
roundParam256(7, 0, 1, 2, 3, 4, 5, 6, 33),
roundParam256(6, 7, 0, 1, 2, 3, 4, 5, 34),
roundParam256(5, 6, 7, 0, 1, 2, 3, 4, 35),
roundParam256(4, 5, 6, 7, 0, 1, 2, 3, 36),
roundParam256(3, 4, 5, 6, 7, 0, 1, 2, 37),
roundParam256(2, 3, 4, 5, 6, 7, 0, 1, 38),
roundParam256(1, 2, 3, 4, 5, 6, 7, 0, 39),
roundParam256(0, 1, 2, 3, 4, 5, 6, 7, 40),
roundParam256(7, 0, 1, 2, 3, 4, 5, 6, 41),
roundParam256(6, 7, 0, 1, 2, 3, 4, 5, 42),
roundParam256(5, 6, 7, 0, 1, 2, 3, 4, 43),
roundParam256(4, 5, 6, 7, 0, 1, 2, 3, 44),
roundParam256(3, 4, 5, 6, 7, 0, 1, 2, 45),
roundParam256(2, 3, 4, 5, 6, 7, 0, 1, 46),
roundParam256(1, 2, 3, 4, 5, 6, 7, 0, 47),
roundParam256(0, 1, 2, 3, 4, 5, 6, 7, 48),
roundParam256(7, 0, 1, 2, 3, 4, 5, 6, 49),
roundParam256(6, 7, 0, 1, 2, 3, 4, 5, 50),
roundParam256(5, 6, 7, 0, 1, 2, 3, 4, 51),
roundParam256(4, 5, 6, 7, 0, 1, 2, 3, 52),
roundParam256(3, 4, 5, 6, 7, 0, 1, 2, 53),
roundParam256(2, 3, 4, 5, 6, 7, 0, 1, 54),
roundParam256(1, 2, 3, 4, 5, 6, 7, 0, 55),
roundParam256(0, 1, 2, 3, 4, 5, 6, 7, 56),
roundParam256(7, 0, 1, 2, 3, 4, 5, 6, 57),
roundParam256(6, 7, 0, 1, 2, 3, 4, 5, 58),
roundParam256(5, 6, 7, 0, 1, 2, 3, 4, 59),
roundParam256(4, 5, 6, 7, 0, 1, 2, 3, 60),
roundParam256(3, 4, 5, 6, 7, 0, 1, 2, 61),
roundParam256(2, 3, 4, 5, 6, 7, 0, 1, 62),
roundParam256(1, 2, 3, 4, 5, 6, 7, 0, 63),
};
inline for (round0) |r| {
v[r.h] = v[r.h] +% (math.rotr(u32, v[r.e], @as(u32, 6)) ^ math.rotr(u32, v[r.e], @as(u32, 11)) ^ math.rotr(u32, v[r.e], @as(u32, 25))) +% (v[r.g] ^ (v[r.e] & (v[r.f] ^ v[r.g]))) +% W[r.i] +% s[r.i];
v[r.d] = v[r.d] +% v[r.h];
v[r.h] = v[r.h] +% (math.rotr(u32, v[r.a], @as(u32, 2)) ^ math.rotr(u32, v[r.a], @as(u32, 13)) ^ math.rotr(u32, v[r.a], @as(u32, 22))) +% ((v[r.a] & (v[r.b] | v[r.c])) | (v[r.b] & v[r.c]));
}
for (&d.s, v) |*dv, vv| dv.* +%= vv;
}
};
}
