zig/lib/std/crypto/sha1.zig
Andrew Kelley d29871977f remove redundant license headers from zig standard library
We already have a LICENSE file that covers the Zig Standard Library. We
no longer need to remind everyone that the license is MIT in every single
file.

Previously this was introduced to clarify the situation for a fork of
Zig that made Zig's LICENSE file harder to find, and replaced it with
their own license that required annual payments to their company.
However that fork now appears to be dead. So there is no need to
reinforce the copyright notice in every single file.
2021-08-24 12:25:09 -07:00

297 lines
10 KiB
Zig

const std = @import("../std.zig");
const mem = std.mem;
const math = std.math;
const RoundParam = struct {
a: usize,
b: usize,
c: usize,
d: usize,
e: usize,
i: u32,
};
fn roundParam(a: usize, b: usize, c: usize, d: usize, e: usize, i: u32) RoundParam {
return RoundParam{
.a = a,
.b = b,
.c = c,
.d = d,
.e = e,
.i = i,
};
}
/// The SHA-1 function is now considered cryptographically broken.
/// Namely, it is feasible to find multiple inputs producing the same hash.
/// For a fast-performing, cryptographically secure hash function, see SHA512/256, BLAKE2 or BLAKE3.
pub const Sha1 = struct {
const Self = @This();
pub const block_length = 64;
pub const digest_length = 20;
pub const Options = struct {};
s: [5]u32,
// Streaming Cache
buf: [64]u8 = undefined,
buf_len: u8 = 0,
total_len: u64 = 0,
pub fn init(options: Options) Self {
_ = options;
return Self{
.s = [_]u32{
0x67452301,
0xEFCDAB89,
0x98BADCFE,
0x10325476,
0xC3D2E1F0,
},
};
}
pub fn hash(b: []const u8, out: *[digest_length]u8, options: Options) void {
var d = Sha1.init(options);
d.update(b);
d.final(out);
}
pub fn update(d: *Self, b: []const u8) void {
var off: usize = 0;
// Partial buffer exists from previous update. Copy into buffer then hash.
if (d.buf_len != 0 and d.buf_len + b.len >= 64) {
off += 64 - d.buf_len;
mem.copy(u8, d.buf[d.buf_len..], b[0..off]);
d.round(d.buf[0..]);
d.buf_len = 0;
}
// Full middle blocks.
while (off + 64 <= b.len) : (off += 64) {
d.round(b[off..][0..64]);
}
// Copy any remainder for next pass.
mem.copy(u8, d.buf[d.buf_len..], b[off..]);
d.buf_len += @intCast(u8, b[off..].len);
d.total_len += b.len;
}
pub fn final(d: *Self, out: *[digest_length]u8) void {
// The buffer here will never be completely full.
mem.set(u8, d.buf[d.buf_len..], 0);
// Append padding bits.
d.buf[d.buf_len] = 0x80;
d.buf_len += 1;
// > 448 mod 512 so need to add an extra round to wrap around.
if (64 - d.buf_len < 8) {
d.round(d.buf[0..]);
mem.set(u8, d.buf[0..], 0);
}
// Append message length.
var i: usize = 1;
var len = d.total_len >> 5;
d.buf[63] = @intCast(u8, d.total_len & 0x1f) << 3;
while (i < 8) : (i += 1) {
d.buf[63 - i] = @intCast(u8, len & 0xff);
len >>= 8;
}
d.round(d.buf[0..]);
for (d.s) |s, j| {
mem.writeIntBig(u32, out[4 * j ..][0..4], s);
}
}
fn round(d: *Self, b: *const [64]u8) void {
var s: [16]u32 = undefined;
var v: [5]u32 = [_]u32{
d.s[0],
d.s[1],
d.s[2],
d.s[3],
d.s[4],
};
const round0a = comptime [_]RoundParam{
roundParam(0, 1, 2, 3, 4, 0),
roundParam(4, 0, 1, 2, 3, 1),
roundParam(3, 4, 0, 1, 2, 2),
roundParam(2, 3, 4, 0, 1, 3),
roundParam(1, 2, 3, 4, 0, 4),
roundParam(0, 1, 2, 3, 4, 5),
roundParam(4, 0, 1, 2, 3, 6),
roundParam(3, 4, 0, 1, 2, 7),
roundParam(2, 3, 4, 0, 1, 8),
roundParam(1, 2, 3, 4, 0, 9),
roundParam(0, 1, 2, 3, 4, 10),
roundParam(4, 0, 1, 2, 3, 11),
roundParam(3, 4, 0, 1, 2, 12),
roundParam(2, 3, 4, 0, 1, 13),
roundParam(1, 2, 3, 4, 0, 14),
roundParam(0, 1, 2, 3, 4, 15),
};
inline for (round0a) |r| {
s[r.i] = (@as(u32, b[r.i * 4 + 0]) << 24) | (@as(u32, b[r.i * 4 + 1]) << 16) | (@as(u32, b[r.i * 4 + 2]) << 8) | (@as(u32, b[r.i * 4 + 3]) << 0);
v[r.e] = v[r.e] +% math.rotl(u32, v[r.a], @as(u32, 5)) +% 0x5A827999 +% s[r.i & 0xf] +% ((v[r.b] & v[r.c]) | (~v[r.b] & v[r.d]));
v[r.b] = math.rotl(u32, v[r.b], @as(u32, 30));
}
const round0b = comptime [_]RoundParam{
roundParam(4, 0, 1, 2, 3, 16),
roundParam(3, 4, 0, 1, 2, 17),
roundParam(2, 3, 4, 0, 1, 18),
roundParam(1, 2, 3, 4, 0, 19),
};
inline for (round0b) |r| {
const t = s[(r.i - 3) & 0xf] ^ s[(r.i - 8) & 0xf] ^ s[(r.i - 14) & 0xf] ^ s[(r.i - 16) & 0xf];
s[r.i & 0xf] = math.rotl(u32, t, @as(u32, 1));
v[r.e] = v[r.e] +% math.rotl(u32, v[r.a], @as(u32, 5)) +% 0x5A827999 +% s[r.i & 0xf] +% ((v[r.b] & v[r.c]) | (~v[r.b] & v[r.d]));
v[r.b] = math.rotl(u32, v[r.b], @as(u32, 30));
}
const round1 = comptime [_]RoundParam{
roundParam(0, 1, 2, 3, 4, 20),
roundParam(4, 0, 1, 2, 3, 21),
roundParam(3, 4, 0, 1, 2, 22),
roundParam(2, 3, 4, 0, 1, 23),
roundParam(1, 2, 3, 4, 0, 24),
roundParam(0, 1, 2, 3, 4, 25),
roundParam(4, 0, 1, 2, 3, 26),
roundParam(3, 4, 0, 1, 2, 27),
roundParam(2, 3, 4, 0, 1, 28),
roundParam(1, 2, 3, 4, 0, 29),
roundParam(0, 1, 2, 3, 4, 30),
roundParam(4, 0, 1, 2, 3, 31),
roundParam(3, 4, 0, 1, 2, 32),
roundParam(2, 3, 4, 0, 1, 33),
roundParam(1, 2, 3, 4, 0, 34),
roundParam(0, 1, 2, 3, 4, 35),
roundParam(4, 0, 1, 2, 3, 36),
roundParam(3, 4, 0, 1, 2, 37),
roundParam(2, 3, 4, 0, 1, 38),
roundParam(1, 2, 3, 4, 0, 39),
};
inline for (round1) |r| {
const t = s[(r.i - 3) & 0xf] ^ s[(r.i - 8) & 0xf] ^ s[(r.i - 14) & 0xf] ^ s[(r.i - 16) & 0xf];
s[r.i & 0xf] = math.rotl(u32, t, @as(u32, 1));
v[r.e] = v[r.e] +% math.rotl(u32, v[r.a], @as(u32, 5)) +% 0x6ED9EBA1 +% s[r.i & 0xf] +% (v[r.b] ^ v[r.c] ^ v[r.d]);
v[r.b] = math.rotl(u32, v[r.b], @as(u32, 30));
}
const round2 = comptime [_]RoundParam{
roundParam(0, 1, 2, 3, 4, 40),
roundParam(4, 0, 1, 2, 3, 41),
roundParam(3, 4, 0, 1, 2, 42),
roundParam(2, 3, 4, 0, 1, 43),
roundParam(1, 2, 3, 4, 0, 44),
roundParam(0, 1, 2, 3, 4, 45),
roundParam(4, 0, 1, 2, 3, 46),
roundParam(3, 4, 0, 1, 2, 47),
roundParam(2, 3, 4, 0, 1, 48),
roundParam(1, 2, 3, 4, 0, 49),
roundParam(0, 1, 2, 3, 4, 50),
roundParam(4, 0, 1, 2, 3, 51),
roundParam(3, 4, 0, 1, 2, 52),
roundParam(2, 3, 4, 0, 1, 53),
roundParam(1, 2, 3, 4, 0, 54),
roundParam(0, 1, 2, 3, 4, 55),
roundParam(4, 0, 1, 2, 3, 56),
roundParam(3, 4, 0, 1, 2, 57),
roundParam(2, 3, 4, 0, 1, 58),
roundParam(1, 2, 3, 4, 0, 59),
};
inline for (round2) |r| {
const t = s[(r.i - 3) & 0xf] ^ s[(r.i - 8) & 0xf] ^ s[(r.i - 14) & 0xf] ^ s[(r.i - 16) & 0xf];
s[r.i & 0xf] = math.rotl(u32, t, @as(u32, 1));
v[r.e] = v[r.e] +% math.rotl(u32, v[r.a], @as(u32, 5)) +% 0x8F1BBCDC +% s[r.i & 0xf] +% ((v[r.b] & v[r.c]) ^ (v[r.b] & v[r.d]) ^ (v[r.c] & v[r.d]));
v[r.b] = math.rotl(u32, v[r.b], @as(u32, 30));
}
const round3 = comptime [_]RoundParam{
roundParam(0, 1, 2, 3, 4, 60),
roundParam(4, 0, 1, 2, 3, 61),
roundParam(3, 4, 0, 1, 2, 62),
roundParam(2, 3, 4, 0, 1, 63),
roundParam(1, 2, 3, 4, 0, 64),
roundParam(0, 1, 2, 3, 4, 65),
roundParam(4, 0, 1, 2, 3, 66),
roundParam(3, 4, 0, 1, 2, 67),
roundParam(2, 3, 4, 0, 1, 68),
roundParam(1, 2, 3, 4, 0, 69),
roundParam(0, 1, 2, 3, 4, 70),
roundParam(4, 0, 1, 2, 3, 71),
roundParam(3, 4, 0, 1, 2, 72),
roundParam(2, 3, 4, 0, 1, 73),
roundParam(1, 2, 3, 4, 0, 74),
roundParam(0, 1, 2, 3, 4, 75),
roundParam(4, 0, 1, 2, 3, 76),
roundParam(3, 4, 0, 1, 2, 77),
roundParam(2, 3, 4, 0, 1, 78),
roundParam(1, 2, 3, 4, 0, 79),
};
inline for (round3) |r| {
const t = s[(r.i - 3) & 0xf] ^ s[(r.i - 8) & 0xf] ^ s[(r.i - 14) & 0xf] ^ s[(r.i - 16) & 0xf];
s[r.i & 0xf] = math.rotl(u32, t, @as(u32, 1));
v[r.e] = v[r.e] +% math.rotl(u32, v[r.a], @as(u32, 5)) +% 0xCA62C1D6 +% s[r.i & 0xf] +% (v[r.b] ^ v[r.c] ^ v[r.d]);
v[r.b] = math.rotl(u32, v[r.b], @as(u32, 30));
}
d.s[0] +%= v[0];
d.s[1] +%= v[1];
d.s[2] +%= v[2];
d.s[3] +%= v[3];
d.s[4] +%= v[4];
}
};
const htest = @import("test.zig");
test "sha1 single" {
try htest.assertEqualHash(Sha1, "da39a3ee5e6b4b0d3255bfef95601890afd80709", "");
try htest.assertEqualHash(Sha1, "a9993e364706816aba3e25717850c26c9cd0d89d", "abc");
try htest.assertEqualHash(Sha1, "a49b2446a02c645bf419f995b67091253a04a259", "abcdefghbcdefghicdefghijdefghijkefghijklfghijklmghijklmnhijklmnoijklmnopjklmnopqklmnopqrlmnopqrsmnopqrstnopqrstu");
}
test "sha1 streaming" {
var h = Sha1.init(.{});
var out: [20]u8 = undefined;
h.final(&out);
try htest.assertEqual("da39a3ee5e6b4b0d3255bfef95601890afd80709", out[0..]);
h = Sha1.init(.{});
h.update("abc");
h.final(&out);
try htest.assertEqual("a9993e364706816aba3e25717850c26c9cd0d89d", out[0..]);
h = Sha1.init(.{});
h.update("a");
h.update("b");
h.update("c");
h.final(&out);
try htest.assertEqual("a9993e364706816aba3e25717850c26c9cd0d89d", out[0..]);
}
test "sha1 aligned final" {
var block = [_]u8{0} ** Sha1.block_length;
var out: [Sha1.digest_length]u8 = undefined;
var h = Sha1.init(.{});
h.update(&block);
h.final(out[0..]);
}