    /// Authenticated Encryption with Associated Data
    pub const aead = struct {
        pub const aegis = struct {
            pub const Aegis128L = @import("crypto/aegis.zig").Aegis128L;
            pub const Aegis256 = @import("crypto/aegis.zig").Aegis256;
        };

        pub const aes_gcm = struct {
            pub const Aes128Gcm = @import("crypto/aes_gcm.zig").Aes128Gcm;
            pub const Aes256Gcm = @import("crypto/aes_gcm.zig").Aes256Gcm;
        };

        pub const aes_ocb = struct {
            pub const Aes128Ocb = @import("crypto/aes_ocb.zig").Aes128Ocb;
            pub const Aes256Ocb = @import("crypto/aes_ocb.zig").Aes256Ocb;
        };

        pub const Gimli = @import("crypto/gimli.zig").Aead;

        pub const chacha_poly = struct {
            pub const ChaCha20Poly1305 = @import("crypto/chacha20.zig").ChaCha20Poly1305;
            pub const ChaCha12Poly1305 = @import("crypto/chacha20.zig").ChaCha12Poly1305;
            pub const ChaCha8Poly1305 = @import("crypto/chacha20.zig").ChaCha8Poly1305;
            pub const XChaCha20Poly1305 = @import("crypto/chacha20.zig").XChaCha20Poly1305;
            pub const XChaCha12Poly1305 = @import("crypto/chacha20.zig").XChaCha12Poly1305;
            pub const XChaCha8Poly1305 = @import("crypto/chacha20.zig").XChaCha8Poly1305;
        };

        pub const isap = @import("crypto/isap.zig");

        pub const salsa_poly = struct {
            pub const XSalsa20Poly1305 = @import("crypto/salsa20.zig").XSalsa20Poly1305;
        };
    };

    /// Authentication (MAC) functions.
    pub const auth = struct {
        pub const hmac = @import("crypto/hmac.zig");
        pub const siphash = @import("crypto/siphash.zig");
    };

    /// Core functions, that should rarely be used directly by applications.
    pub const core = struct {
        pub const aes = @import("crypto/aes.zig");
        pub const Gimli = @import("crypto/gimli.zig").State;
        pub const Xoodoo = @import("crypto/xoodoo.zig").State;

        /// Modes are generic compositions to construct encryption/decryption functions from block ciphers and permutations.
        ///
        /// These modes are designed to be building blocks for higher-level constructions, and should generally not be used directly by applications, as they may not provide the expected properties and security guarantees.
        ///
        /// Most applications may want to use AEADs instead.
        pub const modes = @import("crypto/modes.zig");
    };

    /// Diffie-Hellman key exchange functions.
    pub const dh = struct {
        pub const X25519 = @import("crypto/25519/x25519.zig").X25519;
    };

    /// Elliptic-curve arithmetic.
    pub const ecc = struct {
        pub const Curve25519 = @import("crypto/25519/curve25519.zig").Curve25519;
        pub const Edwards25519 = @import("crypto/25519/edwards25519.zig").Edwards25519;
        pub const P256 = @import("crypto/pcurves/p256.zig").P256;
        pub const P384 = @import("crypto/pcurves/p384.zig").P384;
        pub const Ristretto255 = @import("crypto/25519/ristretto255.zig").Ristretto255;
        pub const Secp256k1 = @import("crypto/pcurves/secp256k1.zig").Secp256k1;
    };

    /// Hash functions.
    pub const hash = struct {
        pub const blake2 = @import("crypto/blake2.zig");
        pub const Blake3 = @import("crypto/blake3.zig").Blake3;
        pub const Gimli = @import("crypto/gimli.zig").Hash;
        pub const Md5 = @import("crypto/md5.zig").Md5;
        pub const Sha1 = @import("crypto/sha1.zig").Sha1;
        pub const sha2 = @import("crypto/sha2.zig");
        pub const sha3 = @import("crypto/sha3.zig");
        pub const composition = @import("crypto/hash_composition.zig");
    };

    /// Key derivation functions.
    pub const kdf = struct {
        pub const hkdf = @import("crypto/hkdf.zig");
    };

    /// MAC functions requiring single-use secret keys.
    pub const onetimeauth = struct {
        pub const Ghash = @import("crypto/ghash.zig").Ghash;
        pub const Poly1305 = @import("crypto/poly1305.zig").Poly1305;
    };

    /// A password hashing function derives a uniform key from low-entropy input material such as passwords.
    /// It is intentionally slow or expensive.
    ///
    /// With the standard definition of a key derivation function, if a key space is small, an exhaustive search may be practical.
    /// Password hashing functions make exhaustive searches way slower or way more expensive, even when implemented on GPUs and ASICs, by using different, optionally combined strategies:
    ///
    /// - Requiring a lot of computation cycles to complete
    /// - Requiring a lot of memory to complete
    /// - Requiring multiple CPU cores to complete
    /// - Requiring cache-local data to complete in reasonable time
    /// - Requiring large static tables
    /// - Avoiding precomputations and time/memory tradeoffs
    /// - Requiring multi-party computations
    /// - Combining the input material with random per-entry data (salts), application-specific contexts and keys
    ///
    /// Password hashing functions must be used whenever sensitive data has to be directly derived from a password.
    pub const pwhash = struct {
        pub const Encoding = enum {
            phc,
            crypt,
        };

        pub const Error = HasherError || error{AllocatorRequired};
        pub const HasherError = KdfError || phc_format.Error;
        pub const KdfError = errors.Error || std.mem.Allocator.Error || std.Thread.SpawnError;

        pub const argon2 = @import("crypto/argon2.zig");
        pub const bcrypt = @import("crypto/bcrypt.zig");
        pub const scrypt = @import("crypto/scrypt.zig");
        pub const pbkdf2 = @import("crypto/pbkdf2.zig").pbkdf2;

        pub const phc_format = @import("crypto/phc_encoding.zig");
    };

    /// Digital signature functions.
    pub const sign = struct {
        pub const Ed25519 = @import("crypto/25519/ed25519.zig").Ed25519;
        pub const ecdsa = @import("crypto/ecdsa.zig");
    };

    /// Stream ciphers. These do not provide any kind of authentication.
    /// Most applications should be using AEAD constructions instead of stream ciphers directly.
    pub const stream = struct {
        pub const chacha = struct {
            pub const ChaCha20IETF = @import("crypto/chacha20.zig").ChaCha20IETF;
            pub const ChaCha12IETF = @import("crypto/chacha20.zig").ChaCha12IETF;
            pub const ChaCha8IETF = @import("crypto/chacha20.zig").ChaCha8IETF;
            pub const ChaCha20With64BitNonce = @import("crypto/chacha20.zig").ChaCha20With64BitNonce;
            pub const ChaCha12With64BitNonce = @import("crypto/chacha20.zig").ChaCha12With64BitNonce;
            pub const ChaCha8With64BitNonce = @import("crypto/chacha20.zig").ChaCha8With64BitNonce;
            pub const XChaCha20IETF = @import("crypto/chacha20.zig").XChaCha20IETF;
            pub const XChaCha12IETF = @import("crypto/chacha20.zig").XChaCha12IETF;
            pub const XChaCha8IETF = @import("crypto/chacha20.zig").XChaCha8IETF;
        };

        pub const salsa = struct {
            pub const Salsa = @import("crypto/salsa20.zig").Salsa;
            pub const XSalsa = @import("crypto/salsa20.zig").XSalsa;
            pub const Salsa20 = @import("crypto/salsa20.zig").Salsa20;
            pub const XSalsa20 = @import("crypto/salsa20.zig").XSalsa20;
        };
    };

    pub const nacl = struct {
        const salsa20 = @import("crypto/salsa20.zig");

        pub const Box = salsa20.Box;
        pub const SecretBox = salsa20.SecretBox;
        pub const SealedBox = salsa20.SealedBox;
    };

    pub const utils = @import("crypto/utils.zig");

    /// This is a thread-local, cryptographically secure pseudo random number generator.
    pub const random = @import("crypto/tlcsprng.zig").interface;

    const std = @import("std.zig");

    pub const errors = @import("crypto/errors.zig");

    test {
        const please_windows_dont_oom = @import("builtin").os.tag == .windows;
        if (please_windows_dont_oom) return error.SkipZigTest;

        _ = aead.aegis.Aegis128L;
        _ = aead.aegis.Aegis256;

        _ = aead.aes_gcm.Aes128Gcm;
        _ = aead.aes_gcm.Aes256Gcm;

        _ = aead.aes_ocb.Aes128Ocb;
        _ = aead.aes_ocb.Aes256Ocb;

        _ = aead.Gimli;

        _ = aead.chacha_poly.ChaCha20Poly1305;
        _ = aead.chacha_poly.ChaCha12Poly1305;
        _ = aead.chacha_poly.ChaCha8Poly1305;
        _ = aead.chacha_poly.XChaCha20Poly1305;
        _ = aead.chacha_poly.XChaCha12Poly1305;
        _ = aead.chacha_poly.XChaCha8Poly1305;

        _ = aead.isap;
        _ = aead.salsa_poly.XSalsa20Poly1305;

        _ = auth.hmac;
        _ = auth.siphash;

        _ = core.aes;
        _ = core.Gimli;
        _ = core.modes;

        _ = dh.X25519;

        _ = ecc.Curve25519;
        _ = ecc.Edwards25519;
        _ = ecc.P256;
        _ = ecc.P384;
        _ = ecc.Ristretto255;
        _ = ecc.Secp256k1;

        _ = hash.blake2;
        _ = hash.Blake3;
        _ = hash.Gimli;
        _ = hash.Md5;
        _ = hash.Sha1;
        _ = hash.sha2;
        _ = hash.sha3;
        _ = hash.composition;

        _ = kdf.hkdf;

        _ = onetimeauth.Ghash;
        _ = onetimeauth.Poly1305;

        _ = pwhash.Encoding;

        _ = pwhash.Error;
        _ = pwhash.HasherError;
        _ = pwhash.KdfError;

        _ = pwhash.argon2;
        _ = pwhash.bcrypt;
        _ = pwhash.scrypt;
        _ = pwhash.pbkdf2;

        _ = pwhash.phc_format;

        _ = sign.Ed25519;
        _ = sign.ecdsa;

        _ = stream.chacha.ChaCha20IETF;
        _ = stream.chacha.ChaCha12IETF;
        _ = stream.chacha.ChaCha8IETF;
        _ = stream.chacha.ChaCha20With64BitNonce;
        _ = stream.chacha.ChaCha12With64BitNonce;
        _ = stream.chacha.ChaCha8With64BitNonce;
        _ = stream.chacha.XChaCha20IETF;
        _ = stream.chacha.XChaCha12IETF;
        _ = stream.chacha.XChaCha8IETF;

        _ = stream.salsa.Salsa20;
        _ = stream.salsa.XSalsa20;

        _ = nacl.Box;
        _ = nacl.SecretBox;
        _ = nacl.SealedBox;

        _ = utils;
        _ = random;
        _ = errors;
    }

    test "CSPRNG" {
        const a = random.int(u64);
        const b = random.int(u64);
        const c = random.int(u64);
        try std.testing.expect(a ^ b ^ c != 0);
    }

    test "issue #4532: no index out of bounds" {
        const types = [_]type{
            hash.Md5,
            hash.Sha1,
            hash.sha2.Sha224,
            hash.sha2.Sha256,
            hash.sha2.Sha384,
            hash.sha2.Sha512,
            hash.sha3.Sha3_224,
            hash.sha3.Sha3_256,
            hash.sha3.Sha3_384,
            hash.sha3.Sha3_512,
            hash.blake2.Blake2s128,
            hash.blake2.Blake2s224,
            hash.blake2.Blake2s256,
            hash.blake2.Blake2b128,
            hash.blake2.Blake2b256,
            hash.blake2.Blake2b384,
            hash.blake2.Blake2b512,
            hash.Gimli,
        };

        inline for (types) |Hasher| {
            var block = [_]u8{'#'} ** Hasher.block_length;
            var out1: [Hasher.digest_length]u8 = undefined;
            var out2: [Hasher.digest_length]u8 = undefined;
            const h0 = Hasher.init(.{});
            var h = h0;
            h.update(block[0..]);
            h.final(&out1);
            h = h0;
            h.update(block[0..1]);
            h.update(block[1..]);
            h.final(&out2);

            try std.testing.expectEqual(out1, out2);
        }
    }