bcrypt_pbkdf.zig

// This is a literal translation of the following file from OpenBSD:
// $OpenBSD: bcrypt_pbkdf.c,v 1.13 2015/01/12 03:20:04 tedu
//
// Copyright (c) 2013 Ted Unangst <tedu@openbsd.org>
//
// Permission to use, copy, modify, and distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

const std = @import("std");
const debug = std.debug;
const SHA512 = std.crypto.hash.sha2.Sha512;
const zero = std.crypto.utils.secureZero;
const expect = std.testing.expect;

const bcrypt_words = 8;
const bcrypt_hashsize = bcrypt_words * 4;
const bcrypt_ciphertext = @as([32]u8, "OxychromaticBlowfishSwatDynamite".*);

fn bcrypt_hash(sha2pass: []const u8, sha2salt: []const u8, out: []u8) void {
    var state = Blowfish{};
    var cdata: [bcrypt_words]u32 = undefined;

    // Key expansion
    state.expand(sha2salt, sha2pass);

    var i: u32 = 0;
    while (i < 64) : (i += 1) {
        state.expand0(sha2salt);
        state.expand0(sha2pass);
    }

    // Encryption
    var j: usize = 0;
    i = 0;
    while (i < bcrypt_words) : (i += 1) {
        cdata[i] = Blowfish.toWord(&bcrypt_ciphertext, &j);
    }
    i = 0;
    while (i < 64) : (i += 1) {
        state.encrypt(&cdata);
    }

    // Copy out
    i = 0;
    while (i < bcrypt_words) : (i += 1) {
        out[4 * i + 3] = @truncate(u8, cdata[i] >> 24);
        out[4 * i + 2] = @truncate(u8, cdata[i] >> 16);
        out[4 * i + 1] = @truncate(u8, cdata[i] >> 8);
        out[4 * i + 0] = @truncate(u8, cdata[i] & 0xff);
    }

    // ZAP
    zero(u32, &cdata);
    zerosingle(&state);
}

fn zerosingle(obj: anytype) void {
    zero(@TypeOf(obj.*), @as(*[1]@TypeOf(obj.*), obj));
}

/// Performs a bcrypt_pbkdf key derivation based on *passphrase*, *salt* and *rounds*,
/// writing the result into *key*.
pub fn bcrypt_pbkdf(passphrase: []const u8, salt: []const u8, key: []u8, rounds: u32) !void {
    var out: [bcrypt_hashsize]u8 = undefined;
    var tmpout: [bcrypt_hashsize]u8 = undefined;
    var sha2pass: [SHA512.digest_length]u8 = undefined;
    var sha2salt: [SHA512.digest_length]u8 = undefined;

    // Check parameters
    if (rounds < 1)
        return error.BCryptError;
    if (passphrase.len == 0 or salt.len == 0 or key.len == 0 or key.len > out.len * out.len)
        return error.BCryptError;

    const stride = (key.len + out.len - 1) / out.len;
    var amt = (key.len + stride - 1) / stride;

    // Collapse password
    SHA512.hash(passphrase, &sha2pass, .{});

    var count: u32 = 1;
    var key_to_gen = key.len;

    // generate key in chunks of out.len
    while (key_to_gen > 0) : (count += 1) {
        const countsalt = [4]u8{
            @truncate(u8, count >> 24),
            @truncate(u8, count >> 16),
            @truncate(u8, count >> 8),
            @truncate(u8, count & 0xff),
        };

        // first round, salt is the salt given to us
        var ctx = SHA512.init(.{});
        defer zerosingle(&ctx);
        ctx.update(salt);
        ctx.update(countsalt[0..]);
        ctx.final(&sha2salt);
        bcrypt_hash(&sha2pass, &sha2salt, &tmpout);
        std.mem.copy(u8, &out, &tmpout);

        var i: u32 = 1;
        while (i < rounds) : (i += 1) {
            // subsequent rounds, salt is the previous output
            SHA512.hash(&tmpout, &sha2salt, .{});
            bcrypt_hash(&sha2pass, &sha2salt, &tmpout);
            var j: u32 = 0;
            while (j < out.len) : (j += 1) {
                out[j] ^= tmpout[j];
            }
        }

        // output the key material non-linearly (deviates from pbkdf2)
        amt = std.math.min(amt, key_to_gen);
        i = 0;
        while (i < amt) : (i += 1) {
            const dest = i * stride + (count - 1);
            if (dest >= key.len)
                break;
            key[dest] = out[i];
        }

        key_to_gen -= i;
    }

    zero(u8, &out);
}

/// This is std.crypto.pwhash.bcrypt.State, which is private.
/// SPDX-License-Identifier: MIT
/// Copyright (c) 2015-2021 Zig Contributors
/// This file is part of [zig](https://ziglang.org/), which is MIT licensed.
/// The MIT license requires this copyright notice to be included in all copies
/// and substantial portions of the software.
const Blowfish = struct {
    sboxes: [4][256]u32 = [4][256]u32{
        .{ 0xd1310ba6, 0x98dfb5ac, 0x2ffd72db, 0xd01adfb7, 0xb8e1afed, 0x6a267e96, 0xba7c9045, 0xf12c7f99, 0x24a19947, 0xb3916cf7, 0x0801f2e2, 0x858efc16, 0x636920d8, 0x71574e69, 0xa458fea3, 0xf4933d7e, 0x0d95748f, 0x728eb658, 0x718bcd58, 0x82154aee, 0x7b54a41d, 0xc25a59b5, 0x9c30d539, 0x2af26013, 0xc5d1b023, 0x286085f0, 0xca417918, 0xb8db38ef, 0x8e79dcb0, 0x603a180e, 0x6c9e0e8b, 0xb01e8a3e, 0xd71577c1, 0xbd314b27, 0x78af2fda, 0x55605c60, 0xe65525f3, 0xaa55ab94, 0x57489862, 0x63e81440, 0x55ca396a, 0x2aab10b6, 0xb4cc5c34, 0x1141e8ce, 0xa15486af, 0x7c72e993, 0xb3ee1411, 0x636fbc2a, 0x2ba9c55d, 0x741831f6, 0xce5c3e16, 0x9b87931e, 0xafd6ba33, 0x6c24cf5c, 0x7a325381, 0x28958677, 0x3b8f4898, 0x6b4bb9af, 0xc4bfe81b, 0x66282193, 0x61d809cc, 0xfb21a991, 0x487cac60, 0x5dec8032, 0xef845d5d, 0xe98575b1, 0xdc262302, 0xeb651b88, 0x23893e81, 0xd396acc5, 0x0f6d6ff3, 0x83f44239, 0x2e0b4482, 0xa4842004, 0x69c8f04a, 0x9e1f9b5e, 0x21c66842, 0xf6e96c9a, 0x670c9c61, 0xabd388f0, 0x6a51a0d2, 0xd8542f68, 0x960fa728, 0xab5133a3, 0x6eef0b6c, 0x137a3be4, 0xba3bf050, 0x7efb2a98, 0xa1f1651d, 0x39af0176, 0x66ca593e, 0x82430e88, 0x8cee8619, 0x456f9fb4, 0x7d84a5c3, 0x3b8b5ebe, 0xe06f75d8, 0x85c12073, 0x401a449f, 0x56c16aa6, 0x4ed3aa62, 0x363f7706, 0x1bfedf72, 0x429b023d, 0x37d0d724, 0xd00a1248, 0xdb0fead3, 0x49f1c09b, 0x075372c9, 0x80991b7b, 0x25d479d8, 0xf6e8def7, 0xe3fe501a, 0xb6794c3b, 0x976ce0bd, 0x04c006ba, 0xc1a94fb6, 0x409f60c4, 0x5e5c9ec2, 0x196a2463, 0x68fb6faf, 0x3e6c53b5, 0x1339b2eb, 0x3b52ec6f, 0x6dfc511f, 0x9b30952c, 0xcc814544, 0xaf5ebd09, 0xbee3d004, 0xde334afd, 0x660f2807, 0x192e4bb3, 0xc0cba857, 0x45c8740f, 0xd20b5f39, 0xb9d3fbdb, 0x5579c0bd, 0x1a60320a, 0xd6a100c6, 0x402c7279, 0x679f25fe, 0xfb1fa3cc, 0x8ea5e9f8, 0xdb3222f8, 0x3c7516df, 0xfd616b15, 0x2f501ec8, 0xad0552ab, 0x323db5fa, 0xfd238760, 0x53317b48, 0x3e00df82, 0x9e5c57bb, 0xca6f8ca0, 0x1a87562e, 0xdf1769db, 0xd542a8f6, 0x287effc3, 0xac6732c6, 0x8c4f5573, 0x695b27b0, 0xbbca58c8, 0xe1ffa35d, 0xb8f011a0, 0x10fa3d98, 0xfd2183b8, 0x4afcb56c, 0x2dd1d35b, 0x9a53e479, 0xb6f84565, 0xd28e49bc, 0x4bfb9790, 0xe1ddf2da, 0xa4cb7e33, 0x62fb1341, 0xcee4c6e8, 0xef20cada, 0x36774c01, 0xd07e9efe, 0x2bf11fb4, 0x95dbda4d, 0xae909198, 0xeaad8e71, 0x6b93d5a0, 0xd08ed1d0, 0xafc725e0, 0x8e3c5b2f, 0x8e7594b7, 0x8ff6e2fb, 0xf2122b64, 0x8888b812, 0x900df01c, 0x4fad5ea0, 0x688fc31c, 0xd1cff191, 0xb3a8c1ad, 0x2f2f2218, 0xbe0e1777, 0xea752dfe, 0x8b021fa1, 0xe5a0cc0f, 0xb56f74e8, 0x18acf3d6, 0xce89e299, 0xb4a84fe0, 0xfd13e0b7, 0x7cc43b81, 0xd2ada8d9, 0x165fa266, 0x80957705, 0x93cc7314, 0x211a1477, 0xe6ad2065, 0x77b5fa86, 0xc75442f5, 0xfb9d35cf, 0xebcdaf0c, 0x7b3e89a0, 0xd6411bd3, 0xae1e7e49, 0x00250e2d, 0x2071b35e, 0x226800bb, 0x57b8e0af, 0x2464369b, 0xf009b91e, 0x5563911d, 0x59dfa6aa, 0x78c14389, 0xd95a537f, 0x207d5ba2, 0x02e5b9c5, 0x83260376, 0x6295cfa9, 0x11c81968, 0x4e734a41, 0xb3472dca, 0x7b14a94a, 0x1b510052, 0x9a532915, 0xd60f573f, 0xbc9bc6e4, 0x2b60a476, 0x81e67400, 0x08ba6fb5, 0x571be91f, 0xf296ec6b, 0x2a0dd915, 0xb6636521, 0xe7b9f9b6, 0xff34052e, 0xc5855664, 0x53b02d5d, 0xa99f8fa1, 0x08ba4799, 0x6e85076a },
        .{ 0x4b7a70e9, 0xb5b32944, 0xdb75092e, 0xc4192623, 0xad6ea6b0, 0x49a7df7d, 0x9cee60b8, 0x8fedb266, 0xecaa8c71, 0x699a17ff, 0x5664526c, 0xc2b19ee1, 0x193602a5, 0x75094c29, 0xa0591340, 0xe4183a3e, 0x3f54989a, 0x5b429d65, 0x6b8fe4d6, 0x99f73fd6, 0xa1d29c07, 0xefe830f5, 0x4d2d38e6, 0xf0255dc1, 0x4cdd2086, 0x8470eb26, 0x6382e9c6, 0x021ecc5e, 0x09686b3f, 0x3ebaefc9, 0x3c971814, 0x6b6a70a1, 0x687f3584, 0x52a0e286, 0xb79c5305, 0xaa500737, 0x3e07841c, 0x7fdeae5c, 0x8e7d44ec, 0x5716f2b8, 0xb03ada37, 0xf0500c0d, 0xf01c1f04, 0x0200b3ff, 0xae0cf51a, 0x3cb574b2, 0x25837a58, 0xdc0921bd, 0xd19113f9, 0x7ca92ff6, 0x94324773, 0x22f54701, 0x3ae5e581, 0x37c2dadc, 0xc8b57634, 0x9af3dda7, 0xa9446146, 0x0fd0030e, 0xecc8c73e, 0xa4751e41, 0xe238cd99, 0x3bea0e2f, 0x3280bba1, 0x183eb331, 0x4e548b38, 0x4f6db908, 0x6f420d03, 0xf60a04bf, 0x2cb81290, 0x24977c79, 0x5679b072, 0xbcaf89af, 0xde9a771f, 0xd9930810, 0xb38bae12, 0xdccf3f2e, 0x5512721f, 0x2e6b7124, 0x501adde6, 0x9f84cd87, 0x7a584718, 0x7408da17, 0xbc9f9abc, 0xe94b7d8c, 0xec7aec3a, 0xdb851dfa, 0x63094366, 0xc464c3d2, 0xef1c1847, 0x3215d908, 0xdd433b37, 0x24c2ba16, 0x12a14d43, 0x2a65c451, 0x50940002, 0x133ae4dd, 0x71dff89e, 0x10314e55, 0x81ac77d6, 0x5f11199b, 0x043556f1, 0xd7a3c76b, 0x3c11183b, 0x5924a509, 0xf28fe6ed, 0x97f1fbfa, 0x9ebabf2c, 0x1e153c6e, 0x86e34570, 0xeae96fb1, 0x860e5e0a, 0x5a3e2ab3, 0x771fe71c, 0x4e3d06fa, 0x2965dcb9, 0x99e71d0f, 0x803e89d6, 0x5266c825, 0x2e4cc978, 0x9c10b36a, 0xc6150eba, 0x94e2ea78, 0xa5fc3c53, 0x1e0a2df4, 0xf2f74ea7, 0x361d2b3d, 0x1939260f, 0x19c27960, 0x5223a708, 0xf71312b6, 0xebadfe6e, 0xeac31f66, 0xe3bc4595, 0xa67bc883, 0xb17f37d1, 0x018cff28, 0xc332ddef, 0xbe6c5aa5, 0x65582185, 0x68ab9802, 0xeecea50f, 0xdb2f953b, 0x2aef7dad, 0x5b6e2f84, 0x1521b628, 0x29076170, 0xecdd4775, 0x619f1510, 0x13cca830, 0xeb61bd96, 0x0334fe1e, 0xaa0363cf, 0xb5735c90, 0x4c70a239, 0xd59e9e0b, 0xcbaade14, 0xeecc86bc, 0x60622ca7, 0x9cab5cab, 0xb2f3846e, 0x648b1eaf, 0x19bdf0ca, 0xa02369b9, 0x655abb50, 0x40685a32, 0x3c2ab4b3, 0x319ee9d5, 0xc021b8f7, 0x9b540b19, 0x875fa099, 0x95f7997e, 0x623d7da8, 0xf837889a, 0x97e32d77, 0x11ed935f, 0x16681281, 0x0e358829, 0xc7e61fd6, 0x96dedfa1, 0x7858ba99, 0x57f584a5, 0x1b227263, 0x9b83c3ff, 0x1ac24696, 0xcdb30aeb, 0x532e3054, 0x8fd948e4, 0x6dbc3128, 0x58ebf2ef, 0x34c6ffea, 0xfe28ed61, 0xee7c3c73, 0x5d4a14d9, 0xe864b7e3, 0x42105d14, 0x203e13e0, 0x45eee2b6, 0xa3aaabea, 0xdb6c4f15, 0xfacb4fd0, 0xc742f442, 0xef6abbb5, 0x654f3b1d, 0x41cd2105, 0xd81e799e, 0x86854dc7, 0xe44b476a, 0x3d816250, 0xcf62a1f2, 0x5b8d2646, 0xfc8883a0, 0xc1c7b6a3, 0x7f1524c3, 0x69cb7492, 0x47848a0b, 0x5692b285, 0x095bbf00, 0xad19489d, 0x1462b174, 0x23820e00, 0x58428d2a, 0x0c55f5ea, 0x1dadf43e, 0x233f7061, 0x3372f092, 0x8d937e41, 0xd65fecf1, 0x6c223bdb, 0x7cde3759, 0xcbee7460, 0x4085f2a7, 0xce77326e, 0xa6078084, 0x19f8509e, 0xe8efd855, 0x61d99735, 0xa969a7aa, 0xc50c06c2, 0x5a04abfc, 0x800bcadc, 0x9e447a2e, 0xc3453484, 0xfdd56705, 0x0e1e9ec9, 0xdb73dbd3, 0x105588cd, 0x675fda79, 0xe3674340, 0xc5c43465, 0x713e38d8, 0x3d28f89e, 0xf16dff20, 0x153e21e7, 0x8fb03d4a, 0xe6e39f2b, 0xdb83adf7 },
        .{ 0xe93d5a68, 0x948140f7, 0xf64c261c, 0x94692934, 0x411520f7, 0x7602d4f7, 0xbcf46b2e, 0xd4a20068, 0xd4082471, 0x3320f46a, 0x43b7d4b7, 0x500061af, 0x1e39f62e, 0x97244546, 0x14214f74, 0xbf8b8840, 0x4d95fc1d, 0x96b591af, 0x70f4ddd3, 0x66a02f45, 0xbfbc09ec, 0x03bd9785, 0x7fac6dd0, 0x31cb8504, 0x96eb27b3, 0x55fd3941, 0xda2547e6, 0xabca0a9a, 0x28507825, 0x530429f4, 0x0a2c86da, 0xe9b66dfb, 0x68dc1462, 0xd7486900, 0x680ec0a4, 0x27a18dee, 0x4f3ffea2, 0xe887ad8c, 0xb58ce006, 0x7af4d6b6, 0xaace1e7c, 0xd3375fec, 0xce78a399, 0x406b2a42, 0x20fe9e35, 0xd9f385b9, 0xee39d7ab, 0x3b124e8b, 0x1dc9faf7, 0x4b6d1856, 0x26a36631, 0xeae397b2, 0x3a6efa74, 0xdd5b4332, 0x6841e7f7, 0xca7820fb, 0xfb0af54e, 0xd8feb397, 0x454056ac, 0xba489527, 0x55533a3a, 0x20838d87, 0xfe6ba9b7, 0xd096954b, 0x55a867bc, 0xa1159a58, 0xcca92963, 0x99e1db33, 0xa62a4a56, 0x3f3125f9, 0x5ef47e1c, 0x9029317c, 0xfdf8e802, 0x04272f70, 0x80bb155c, 0x05282ce3, 0x95c11548, 0xe4c66d22, 0x48c1133f, 0xc70f86dc, 0x07f9c9ee, 0x41041f0f, 0x404779a4, 0x5d886e17, 0x325f51eb, 0xd59bc0d1, 0xf2bcc18f, 0x41113564, 0x257b7834, 0x602a9c60, 0xdff8e8a3, 0x1f636c1b, 0x0e12b4c2, 0x02e1329e, 0xaf664fd1, 0xcad18115, 0x6b2395e0, 0x333e92e1, 0x3b240b62, 0xeebeb922, 0x85b2a20e, 0xe6ba0d99, 0xde720c8c, 0x2da2f728, 0xd0127845, 0x95b794fd, 0x647d0862, 0xe7ccf5f0, 0x5449a36f, 0x877d48fa, 0xc39dfd27, 0xf33e8d1e, 0x0a476341, 0x992eff74, 0x3a6f6eab, 0xf4f8fd37, 0xa812dc60, 0xa1ebddf8, 0x991be14c, 0xdb6e6b0d, 0xc67b5510, 0x6d672c37, 0x2765d43b, 0xdcd0e804, 0xf1290dc7, 0xcc00ffa3, 0xb5390f92, 0x690fed0b, 0x667b9ffb, 0xcedb7d9c, 0xa091cf0b, 0xd9155ea3, 0xbb132f88, 0x515bad24, 0x7b9479bf, 0x763bd6eb, 0x37392eb3, 0xcc115979, 0x8026e297, 0xf42e312d, 0x6842ada7, 0xc66a2b3b, 0x12754ccc, 0x782ef11c, 0x6a124237, 0xb79251e7, 0x06a1bbe6, 0x4bfb6350, 0x1a6b1018, 0x11caedfa, 0x3d25bdd8, 0xe2e1c3c9, 0x44421659, 0x0a121386, 0xd90cec6e, 0xd5abea2a, 0x64af674e, 0xda86a85f, 0xbebfe988, 0x64e4c3fe, 0x9dbc8057, 0xf0f7c086, 0x60787bf8, 0x6003604d, 0xd1fd8346, 0xf6381fb0, 0x7745ae04, 0xd736fccc, 0x83426b33, 0xf01eab71, 0xb0804187, 0x3c005e5f, 0x77a057be, 0xbde8ae24, 0x55464299, 0xbf582e61, 0x4e58f48f, 0xf2ddfda2, 0xf474ef38, 0x8789bdc2, 0x5366f9c3, 0xc8b38e74, 0xb475f255, 0x46fcd9b9, 0x7aeb2661, 0x8b1ddf84, 0x846a0e79, 0x915f95e2, 0x466e598e, 0x20b45770, 0x8cd55591, 0xc902de4c, 0xb90bace1, 0xbb8205d0, 0x11a86248, 0x7574a99e, 0xb77f19b6, 0xe0a9dc09, 0x662d09a1, 0xc4324633, 0xe85a1f02, 0x09f0be8c, 0x4a99a025, 0x1d6efe10, 0x1ab93d1d, 0x0ba5a4df, 0xa186f20f, 0x2868f169, 0xdcb7da83, 0x573906fe, 0xa1e2ce9b, 0x4fcd7f52, 0x50115e01, 0xa70683fa, 0xa002b5c4, 0x0de6d027, 0x9af88c27, 0x773f8641, 0xc3604c06, 0x61a806b5, 0xf0177a28, 0xc0f586e0, 0x006058aa, 0x30dc7d62, 0x11e69ed7, 0x2338ea63, 0x53c2dd94, 0xc2c21634, 0xbbcbee56, 0x90bcb6de, 0xebfc7da1, 0xce591d76, 0x6f05e409, 0x4b7c0188, 0x39720a3d, 0x7c927c24, 0x86e3725f, 0x724d9db9, 0x1ac15bb4, 0xd39eb8fc, 0xed545578, 0x08fca5b5, 0xd83d7cd3, 0x4dad0fc4, 0x1e50ef5e, 0xb161e6f8, 0xa28514d9, 0x6c51133c, 0x6fd5c7e7, 0x56e14ec4, 0x362abfce, 0xddc6c837, 0xd79a3234, 0x92638212, 0x670efa8e, 0x406000e0 },
        .{ 0x3a39ce37, 0xd3faf5cf, 0xabc27737, 0x5ac52d1b, 0x5cb0679e, 0x4fa33742, 0xd3822740, 0x99bc9bbe, 0xd5118e9d, 0xbf0f7315, 0xd62d1c7e, 0xc700c47b, 0xb78c1b6b, 0x21a19045, 0xb26eb1be, 0x6a366eb4, 0x5748ab2f, 0xbc946e79, 0xc6a376d2, 0x6549c2c8, 0x530ff8ee, 0x468dde7d, 0xd5730a1d, 0x4cd04dc6, 0x2939bbdb, 0xa9ba4650, 0xac9526e8, 0xbe5ee304, 0xa1fad5f0, 0x6a2d519a, 0x63ef8ce2, 0x9a86ee22, 0xc089c2b8, 0x43242ef6, 0xa51e03aa, 0x9cf2d0a4, 0x83c061ba, 0x9be96a4d, 0x8fe51550, 0xba645bd6, 0x2826a2f9, 0xa73a3ae1, 0x4ba99586, 0xef5562e9, 0xc72fefd3, 0xf752f7da, 0x3f046f69, 0x77fa0a59, 0x80e4a915, 0x87b08601, 0x9b09e6ad, 0x3b3ee593, 0xe990fd5a, 0x9e34d797, 0x2cf0b7d9, 0x022b8b51, 0x96d5ac3a, 0x017da67d, 0xd1cf3ed6, 0x7c7d2d28, 0x1f9f25cf, 0xadf2b89b, 0x5ad6b472, 0x5a88f54c, 0xe029ac71, 0xe019a5e6, 0x47b0acfd, 0xed93fa9b, 0xe8d3c48d, 0x283b57cc, 0xf8d56629, 0x79132e28, 0x785f0191, 0xed756055, 0xf7960e44, 0xe3d35e8c, 0x15056dd4, 0x88f46dba, 0x03a16125, 0x0564f0bd, 0xc3eb9e15, 0x3c9057a2, 0x97271aec, 0xa93a072a, 0x1b3f6d9b, 0x1e6321f5, 0xf59c66fb, 0x26dcf319, 0x7533d928, 0xb155fdf5, 0x03563482, 0x8aba3cbb, 0x28517711, 0xc20ad9f8, 0xabcc5167, 0xccad925f, 0x4de81751, 0x3830dc8e, 0x379d5862, 0x9320f991, 0xea7a90c2, 0xfb3e7bce, 0x5121ce64, 0x774fbe32, 0xa8b6e37e, 0xc3293d46, 0x48de5369, 0x6413e680, 0xa2ae0810, 0xdd6db224, 0x69852dfd, 0x09072166, 0xb39a460a, 0x6445c0dd, 0x586cdecf, 0x1c20c8ae, 0x5bbef7dd, 0x1b588d40, 0xccd2017f, 0x6bb4e3bb, 0xdda26a7e, 0x3a59ff45, 0x3e350a44, 0xbcb4cdd5, 0x72eacea8, 0xfa6484bb, 0x8d6612ae, 0xbf3c6f47, 0xd29be463, 0x542f5d9e, 0xaec2771b, 0xf64e6370, 0x740e0d8d, 0xe75b1357, 0xf8721671, 0xaf537d5d, 0x4040cb08, 0x4eb4e2cc, 0x34d2466a, 0x0115af84, 0xe1b00428, 0x95983a1d, 0x06b89fb4, 0xce6ea048, 0x6f3f3b82, 0x3520ab82, 0x011a1d4b, 0x277227f8, 0x611560b1, 0xe7933fdc, 0xbb3a792b, 0x344525bd, 0xa08839e1, 0x51ce794b, 0x2f32c9b7, 0xa01fbac9, 0xe01cc87e, 0xbcc7d1f6, 0xcf0111c3, 0xa1e8aac7, 0x1a908749, 0xd44fbd9a, 0xd0dadecb, 0xd50ada38, 0x0339c32a, 0xc6913667, 0x8df9317c, 0xe0b12b4f, 0xf79e59b7, 0x43f5bb3a, 0xf2d519ff, 0x27d9459c, 0xbf97222c, 0x15e6fc2a, 0x0f91fc71, 0x9b941525, 0xfae59361, 0xceb69ceb, 0xc2a86459, 0x12baa8d1, 0xb6c1075e, 0xe3056a0c, 0x10d25065, 0xcb03a442, 0xe0ec6e0e, 0x1698db3b, 0x4c98a0be, 0x3278e964, 0x9f1f9532, 0xe0d392df, 0xd3a0342b, 0x8971f21e, 0x1b0a7441, 0x4ba3348c, 0xc5be7120, 0xc37632d8, 0xdf359f8d, 0x9b992f2e, 0xe60b6f47, 0x0fe3f11d, 0xe54cda54, 0x1edad891, 0xce6279cf, 0xcd3e7e6f, 0x1618b166, 0xfd2c1d05, 0x848fd2c5, 0xf6fb2299, 0xf523f357, 0xa6327623, 0x93a83531, 0x56cccd02, 0xacf08162, 0x5a75ebb5, 0x6e163697, 0x88d273cc, 0xde966292, 0x81b949d0, 0x4c50901b, 0x71c65614, 0xe6c6c7bd, 0x327a140a, 0x45e1d006, 0xc3f27b9a, 0xc9aa53fd, 0x62a80f00, 0xbb25bfe2, 0x35bdd2f6, 0x71126905, 0xb2040222, 0xb6cbcf7c, 0xcd769c2b, 0x53113ec0, 0x1640e3d3, 0x38abbd60, 0x2547adf0, 0xba38209c, 0xf746ce76, 0x77afa1c5, 0x20756060, 0x85cbfe4e, 0x8ae88dd8, 0x7aaaf9b0, 0x4cf9aa7e, 0x1948c25c, 0x02fb8a8c, 0x01c36ae4, 0xd6ebe1f9, 0x90d4f869, 0xa65cdea0, 0x3f09252d, 0xc208e69f, 0xb74e6132, 0xce77e25b, 0x578fdfe3, 0x3ac372e6 },
    },
    subkeys: [18]u32 = [18]u32{ 0x243f6a88, 0x85a308d3, 0x13198a2e, 0x03707344, 0xa4093822, 0x299f31d0, 0x082efa98, 0xec4e6c89, 0x452821e6, 0x38d01377, 0xbe5466cf, 0x34e90c6c, 0xc0ac29b7, 0xc97c50dd, 0x3f84d5b5, 0xb5470917, 0x9216d5d9, 0x8979fb1b },

    fn toWord(data: []const u8, current: *usize) u32 {
        var t: u32 = 0;
        var j = current.*;
        var i: usize = 0;
        while (i < 4) : (i += 1) {
            if (j >= data.len) j = 0;
            t = (t << 8) | data[j];
            j += 1;
        }
        current.* = j;
        return t;
    }

    fn expand0(state: *Blowfish, key: []const u8) void {
        var i: usize = 0;
        var j: usize = 0;
        while (i < state.subkeys.len) : (i += 1) {
            state.subkeys[i] ^= toWord(key, &j);
        }

        var halves = Halves{ .l = 0, .r = 0 };
        i = 0;
        while (i < 18) : (i += 2) {
            state.encipher(&halves);
            state.subkeys[i] = halves.l;
            state.subkeys[i + 1] = halves.r;
        }

        i = 0;
        while (i < 4) : (i += 1) {
            var k: usize = 0;
            while (k < 256) : (k += 2) {
                state.encipher(&halves);
                state.sboxes[i][k] = halves.l;
                state.sboxes[i][k + 1] = halves.r;
            }
        }
    }

    fn expand(state: *Blowfish, data: []const u8, key: []const u8) void {
        var i: usize = 0;
        var j: usize = 0;
        while (i < state.subkeys.len) : (i += 1) {
            state.subkeys[i] ^= toWord(key, &j);
        }

        var halves = Halves{ .l = 0, .r = 0 };
        i = 0;
        j = 0;
        while (i < 18) : (i += 2) {
            halves.l ^= toWord(data, &j);
            halves.r ^= toWord(data, &j);
            state.encipher(&halves);
            state.subkeys[i] = halves.l;
            state.subkeys[i + 1] = halves.r;
        }

        i = 0;
        while (i < 4) : (i += 1) {
            var k: usize = 0;
            while (k < 256) : (k += 2) {
                halves.l ^= toWord(data, &j);
                halves.r ^= toWord(data, &j);
                state.encipher(&halves);
                state.sboxes[i][k] = halves.l;
                state.sboxes[i][k + 1] = halves.r;
            }
        }
    }

    const Halves = struct { l: u32, r: u32 };

    fn feistelF(state: Blowfish, x: u32) u32 {
        var r = state.sboxes[0][@truncate(u8, x >> 24)];
        r +%= state.sboxes[1][@truncate(u8, x >> 16)];
        r ^= state.sboxes[2][@truncate(u8, x >> 8)];
        r +%= state.sboxes[3][@truncate(u8, x)];
        return r;
    }

    fn halfRound(state: Blowfish, i: u32, j: u32, n: usize) u32 {
        return i ^ state.feistelF(j) ^ state.subkeys[n];
    }

    fn encipher(state: Blowfish, halves: *Halves) void {
        halves.l ^= state.subkeys[0];
        var i: usize = 1;
        while (i < 16) : (i += 2) {
            halves.r = state.halfRound(halves.r, halves.l, i);
            halves.l = state.halfRound(halves.l, halves.r, i + 1);
        }
        const halves_last = Halves{ .l = halves.r ^ state.subkeys[i], .r = halves.l };
        halves.* = halves_last;
    }

    fn encrypt(state: Blowfish, data: []u32) void {
        debug.assert(data.len % 2 == 0);
        var i: usize = 0;
        while (i < data.len) : (i += 2) {
            var halves = Halves{ .l = data[i], .r = data[i + 1] };
            state.encipher(&halves);
            data[i] = halves.l;
            data[i + 1] = halves.r;
        }
    }
};

test "basic test vector" {
    var key: [8]u8 = undefined;
    try bcrypt_pbkdf("Hello bcrypt", "Hello salt", &key, 100);
    try expect(std.mem.eql(u8, &key, &[_]u8{ 0x67, 0x5a, 0x52, 0xe5, 0x9, 0x5d, 0x1f, 0xc2 }));
}

// These test vectors come from PyCA/bcrypt, which also contains the OpenBSD bcrypt_pbkdf implementatin
// and some pieces of the OpenBSD libc/crypto (blowfish).
test "PyCA/bcrypt test vectors" {
    const Vector = struct { rounds: u32, passphrase: []const u8, salt: []const u8, key: []const u8 };
    const vectors = &[_]Vector{
        .{
            .rounds = 4,
            .passphrase = "password",
            .salt = "salt",
            .key = "\x5b\xbf\x0c\xc2\x93\x58\x7f\x1c\x36\x35\x55\x5c\x27\x79\x65\x98" ++
                "\xd4\x7e\x57\x90\x71\xbf\x42\x7e\x9d\x8f\xbe\x84\x2a\xba\x34\xd9",
        },
        .{
            .rounds = 4,
            .passphrase = "password",
            .salt = "\x00",
            .key = "\xc1\x2b\x56\x62\x35\xee\xe0\x4c\x21\x25\x98\x97\x0a\x57\x9a\x67",
        },
        .{
            .rounds = 4,
            .passphrase = "\x00",
            .salt = "salt",
            .key = "\x60\x51\xbe\x18\xc2\xf4\xf8\x2c\xbf\x0e\xfe\xe5\x47\x1b\x4b\xb9",
        },
        .{
            // nul bytes in password and string
            .rounds = 4,
            .passphrase = "password\x00",
            .salt = "salt\x00",
            .key = "\x74\x10\xe4\x4c\xf4\xfa\x07\xbf\xaa\xc8\xa9\x28\xb1\x72\x7f\xac" ++
                "\x00\x13\x75\xe7\xbf\x73\x84\x37\x0f\x48\xef\xd1\x21\x74\x30\x50",
        },
        .{
            .rounds = 4,
            .passphrase = "pass\x00wor",
            .salt = "sa\x00l",
            .key = "\xc2\xbf\xfd\x9d\xb3\x8f\x65\x69\xef\xef\x43\x72\xf4\xde\x83\xc0",
        },
        .{
            .rounds = 4,
            .passphrase = "pass\x00word",
            .salt = "sa\x00lt",
            .key = "\x4b\xa4\xac\x39\x25\xc0\xe8\xd7\xf0\xcd\xb6\xbb\x16\x84\xa5\x6f",
        },
        .{
            // bigger key
            .rounds = 8,
            .passphrase = "password",
            .salt = "salt",
            .key = "\xe1\x36\x7e\xc5\x15\x1a\x33\xfa\xac\x4c\xc1\xc1\x44\xcd\x23\xfa" ++
                "\x15\xd5\x54\x84\x93\xec\xc9\x9b\x9b\x5d\x9c\x0d\x3b\x27\xbe\xc7" ++
                "\x62\x27\xea\x66\x08\x8b\x84\x9b\x20\xab\x7a\xa4\x78\x01\x02\x46" ++
                "\xe7\x4b\xba\x51\x72\x3f\xef\xa9\xf9\x47\x4d\x65\x08\x84\x5e\x8d",
        },
        .{
            // more rounds
            .rounds = 42,
            .passphrase = "password",
            .salt = "salt",
            .key = "\x83\x3c\xf0\xdc\xf5\x6d\xb6\x56\x08\xe8\xf0\xdc\x0c\xe8\x82\xbd",
        },
        .{
            // longer password
            .rounds = 8,
            .passphrase = "Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do " ++
                "eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut " ++
                "enim ad minim veniam, quis nostrud exercitation ullamco laboris " ++
                "nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor " ++
                "in reprehenderit in voluptate velit esse cillum dolore eu fugiat " ++
                "nulla pariatur. Excepteur sint occaecat cupidatat non proident, " ++
                "sunt in culpa qui officia deserunt mollit anim id est laborum.",
            .salt = "salis\x00",
            .key = "\x10\x97\x8b\x07\x25\x3d\xf5\x7f\x71\xa1\x62\xeb\x0e\x8a\xd3\x0a",
        },
        .{
            // "unicode"
            .rounds = 8,
            .passphrase = "\x0d\xb3\xac\x94\xb3\xee\x53\x28\x4f\x4a\x22\x89\x3b\x3c\x24\xae",
            .salt = "\x3a\x62\xf0\xf0\xdb\xce\xf8\x23\xcf\xcc\x85\x48\x56\xea\x10\x28",
            .key = "\x20\x44\x38\x17\x5e\xee\x7c\xe1\x36\xc9\x1b\x49\xa6\x79\x23\xff",
        },
        .{
            // very large key
            .rounds = 8,
            .passphrase = "\x0d\xb3\xac\x94\xb3\xee\x53\x28\x4f\x4a\x22\x89\x3b\x3c\x24\xae",
            .salt = "\x3a\x62\xf0\xf0\xdb\xce\xf8\x23\xcf\xcc\x85\x48\x56\xea\x10\x28",
            .key = "\x20\x54\xb9\xff\xf3\x4e\x37\x21\x44\x03\x34\x74\x68\x28\xe9\xed" ++
                "\x38\xde\x4b\x72\xe0\xa6\x9a\xdc\x17\x0a\x13\xb5\xe8\xd6\x46\x38" ++
                "\x5e\xa4\x03\x4a\xe6\xd2\x66\x00\xee\x23\x32\xc5\xed\x40\xad\x55" ++
                "\x7c\x86\xe3\x40\x3f\xbb\x30\xe4\xe1\xdc\x1a\xe0\x6b\x99\xa0\x71" ++
                "\x36\x8f\x51\x8d\x2c\x42\x66\x51\xc9\xe7\xe4\x37\xfd\x6c\x91\x5b" ++
                "\x1b\xbf\xc3\xa4\xce\xa7\x14\x91\x49\x0e\xa7\xaf\xb7\xdd\x02\x90" ++
                "\xa6\x78\xa4\xf4\x41\x12\x8d\xb1\x79\x2e\xab\x27\x76\xb2\x1e\xb4" ++
                "\x23\x8e\x07\x15\xad\xd4\x12\x7d\xff\x44\xe4\xb3\xe4\xcc\x4c\x4f" ++
                "\x99\x70\x08\x3f\x3f\x74\xbd\x69\x88\x73\xfd\xf6\x48\x84\x4f\x75" ++
                "\xc9\xbf\x7f\x9e\x0c\x4d\x9e\x5d\x89\xa7\x78\x39\x97\x49\x29\x66" ++
                "\x61\x67\x07\x61\x1c\xb9\x01\xde\x31\xa1\x97\x26\xb6\xe0\x8c\x3a" ++
                "\x80\x01\x66\x1f\x2d\x5c\x9d\xcc\x33\xb4\xaa\x07\x2f\x90\xdd\x0b" ++
                "\x3f\x54\x8d\x5e\xeb\xa4\x21\x13\x97\xe2\xfb\x06\x2e\x52\x6e\x1d" ++
                "\x68\xf4\x6a\x4c\xe2\x56\x18\x5b\x4b\xad\xc2\x68\x5f\xbe\x78\xe1" ++
                "\xc7\x65\x7b\x59\xf8\x3a\xb9\xab\x80\xcf\x93\x18\xd6\xad\xd1\xf5" ++
                "\x93\x3f\x12\xd6\xf3\x61\x82\xc8\xe8\x11\x5f\x68\x03\x0a\x12\x44",
        },
        .{
            // UTF-8 Greek characters "odysseus" / "telemachos"
            .rounds = 8,
            .passphrase = "\xe1\xbd\x88\xce\xb4\xcf\x85\xcf\x83\xcf\x83\xce\xb5\xcf\x8d\xcf" ++
                "\x82",
            .salt = "\xce\xa4\xce\xb7\xce\xbb\xce\xad\xce\xbc\xce\xb1\xcf\x87\xce\xbf" ++
                "\xcf\x82",
            .key = "\x43\x66\x6c\x9b\x09\xef\x33\xed\x8c\x27\xe8\xe8\xf3\xe2\xd8\xe6",
        },
    };

    const allocator = std.heap.page_allocator;

    for (vectors) |vector| {
        var key = try allocator.alloc(u8, vector.key.len);
        defer allocator.free(key);
        try bcrypt_pbkdf(vector.passphrase, vector.salt, key, vector.rounds);
        try expect(std.mem.eql(u8, key, vector.key));
    }
}