High-level API to libsodium.
npm install js-naclA high-level Javascript API wrapping an
Emscripten-compiled
libsodium, a cryptographic library based on
NaCl. Includes both in-browser and node.js
support.
The paper "The security impact of a new cryptographic
library" is an
excellent summary of the motivation behind the NaCl API and library
design.
Using this library in the browser requires support for the newishwindow.crypto.getRandomValues API.
WARNING: This code will not run in Safari version 5.1.x; or, at
least, will not run when Safari's Javascript debug mode is disabled.
Symptoms include corruption during hash calculation, failures when
unboxing, and failures when producing and verifying signatures. Safari
7.0 seems to be just fine, however. I don't know exactly at which
version Safari started working: I don't have access to enough of a
range of systems. The code has run fine on Chrome and Firefox across
all the versions I've tried.
Version 1.4.0: Updated from libsodium stable-2018-11-19 to 1.0.18-stable.
Version 1.3.2: The Emscripten-compiled code is now configured so that
it no longer adds a listener to the uncaughtException when running
in node.js. See issue #46.
Version 1.3.1: Correct a minor packaging error.
Version 1.3.0: Updated from libsodium 1.0.11 to stable-2018-11-19.
Added crypto_box_seal and crypto_box_seal_open. Switched from
using the Emscripten SDK to using a Dockerized Emscripten to produce
the built version of the library. Because this enables WASM by
default, the approach to handling of requested_total_memory is now
different; see below.
Version 1.2.2: Updated from libsodium 1.0.10 to 1.0.11.
Version 1.2.1: Repaired a mistake where I had failed to export the new
names crypto_sign_seed_keypair and crypto_box_seed_keypair.
Version 1.2.0: js-nacl is now based around libsodium rather than the
plain NaCl tarball. Functions crypto_sign_keypair_from_seed andcrypto_box_keypair_from_seed have been renamed to their libsodium
names, crypto_sign_seed_keypair and crypto_box_seed_keypair
respectively; the old names are still available as aliases, though
deprecated, to be removed in a future version.
Version 1.1.0: API change. The nacl_factory.instantiate function
now expects a callback as its first argument. It calls the callback
with the nacl instance containing the API functions, and returns no
useful value.
Version 0.5.0: API change. Instead of being provided with a modulenacl, with API functions available directly, library importers are
given nacl_factory with a single function instantiate, which
returns a nacl instance containing the API functions.
This library is registered on
npmjs.org. To install it:
npm install js-nacl
The git checkout includes a pre-compiled version of the library, so
you won't need Emscripten unless you want to change something about
the underlying C-language library itself.
Essentially, the source checkout contains everything you will need to
use the library in both the browser and in node.js.
If you do find yourself wanting to build the library, see the
instructions in
BUILDING.md.
In the browser, include the lib/nacl_factory.js script:
...
In node.js, require the lib/nacl_factory.js module:
var nacl_factory = require("./lib/nacl_factory.js");
nacl_factory.instantiate(function (nacl) {
...
console.log(nacl.to_hex(nacl.random_bytes(16)));
});
Or if you have installed the library via npm,
var nacl_factory = require("js-nacl");
nacl_factory.instantiate(function (nacl) {
...
console.log(nacl.to_hex(nacl.random_bytes(16)));
});
In addition, since version 1.3.0, the instantiate function returns aPromise that yields the nacl object.
Pass nacl_factory.instantiate a callback function expecting a single
argument, the nacl module instance.
The nacl_factory.instantiate function expects also a second optional
argument, a dictionary of optional configuration values.
Each call to nacl_factory.instantiate() creates an entirely fresh
module instance, complete with its own private heap area. **Since
v1.3.0:** The heap should automatically grow as required, and should
no longer require manual ahead-of-time configuration.
It's fine to instantiate the module more than once in a single
program, though beware of the large amount of memory potentially taken
up by each instance. The memory assigned to each module instance will
not be released until the instance is garbage collected.
If you notice memory leaks across multiple uses of a single module
instance, please report them, with a test case if at all possible.
The library enforces a strict distinction between strings and binary
data. Binary data is represented using instances ofUint8Array.
Returns a lower-case hexadecimal representation of the given binary
data.
Converts a lower- or upper-case hexadecimal representation of binary
data into the equivalent Uint8Array.
Returns the binary equivalent of the argument, encoded using UTF-8.
Returns the binary equivalent of the argument, encoded using Latin1
(an 8-bit clean encoding). If any of the character codes in the
argument string are greater than 255, an exception is thrown.
Decodes the binary data in the argument using the UTF-8 encoding,
producing the corresponding string.
Decodes the binary data in the argument using the Latin1 8-bit clean
encoding, producing the corresponding string.
Follows the NaCl crypto_hash API.
Computes the SHA-512 hash of its argument.
While SHA-512 is recommended, the SHA-256 function is also available,
as nacl.crypto\_hash\_sha256.
Encodes its argument using nacl.encode_utf8, and then callscrypto_hash.
Follows the NaCl crypto_box API.
You do not need to perform any padding of any arguments to these
functions; the API given here is most similar to the "C++" API in the
NaCl documentation.
**Make sure to follow the instructions regarding nonce selection given
in the "Security model" section of the NaCl API documentation!**
senderKeypair = nacl.crypto_box_keypair();
recipientKeypair = nacl.crypto_box_keypair();
message = nacl.encode_utf8("Hello!");
nonce = nacl.crypto_box_random_nonce();
packet = nacl.crypto_box(message, nonce, recipientKeypair.boxPk, senderKeypair.boxSk);
decoded = nacl.crypto_box_open(packet, nonce, senderKeypair.boxPk, recipientKeypair.boxSk);
"Hello!" === nacl.decode_utf8(decoded); // always true
Creates a fresh random keypair. boxPk is the public key and boxSk
is the secret key.
Returns a fresh randomly-chosen nonce suitable for use withcrypto_box.
Places msg in an authenticated, encrypted box that can only be
verified and decrypted by the secret key corresponding torecipientPublicKey.
Verifies and decrypts a box from crypto_box. Throws an exception if
the verification fails or any of the inputs are invalid.
Precomputes a shared secret between two parties. See the documentation
for crypto_box_beforenm at the NaCl website.
Precomputed-secret variants of crypto_box and crypto_box_open.
Follows the NaCl crypto_secretbox API.
You do not need to perform any padding of any arguments to these
functions; the API given here is most similar to the "C++" API in the
NaCl documentation.
**Make sure to follow the instructions regarding nonce selection given
in the "Security model" section of the NaCl API documentation!**
k = ...;
m = nacl.encode_utf8("message");
n = nacl.crypto_secretbox_random_nonce();
c = nacl.crypto_secretbox(m, n, k);
m1 = nacl.crypto_secretbox_open(c, n, k);
"message" === nacl.decode_utf8(m1); // always true
Returns a fresh randomly-chosen nonce suitable for use withcrypto_secretbox.
Places msg in an authenticated, encrypted box that can only be
verified and decrypted by someone who knows keyBin. The keyBin
Uint8Array must be nacl.crypto_secretbox_KEYBYTES bytes long.
Verifies and decrypts a packet from crypto_secretbox. Throws an
exception if the verification fails or any of the inputs are invalid.
Uses a freshly-created ephemeral box keypair to send an "anonymous"
message to a specific recipient, who is identified by their public box
key, and who may decrypt the message using the matching box keypair.
Places msgBin in an authenticated, encrypted box that can only be
verified and decrypted by the secret key corresponding torecipientPublicKeyBin.
Verifies and decrypts a box from crypto_box_seal. Throws an
exception if the verification fails or any of the inputs are invalid.
Unlike crypto_box_open, no nonce is required, and the recipient's
public key is supplied instead of the sender's. The sender remains
anonymous.
Follows the NaCl crypto_stream API.
**Make sure to follow the instructions regarding nonce selection given
in the "Security model" section of the NaCl API documentation!**
Since this style of secret-key encryption is symmetric,nacl.crypto_stream_xor is suitable for decryption as well as
encryption:
k = ...;
m = nacl.encode_utf8("message");
n = nacl.crypto_stream_random_nonce();
c = nacl.crypto_stream_xor(m, n, k);
m1 = nacl.crypto_stream_xor(c, n, k);
"message" === nacl.decode_utf8(m1); // always true
Returns a fresh randomly-chosen nonce suitable for use withcrypto_stream.
Returns a lenInt-byte length keystream based on the given nonce and
key. The key must be nacl.crypto_stream_KEYBYTES bytes long.
Returns msgBin.length bytes of ciphertext (or plaintext, depending
on the contents of msgBin) produced by XORing msgBin with the
result of nacl.crypto_stream(msgBin.length, nonceBin, keyBin).
Follows the NaCl crypto_onetimeauth API.
Follows the NaCl crypto_auth API.
Follows the NaCl crypto_sign API.
Note that this uses the version of Ed25519
from SUPERCOP, and not the
old prototype implementation from the nacl 20110221 release.
The SUPERCOP Ed25519 signature scheme used is compatible with
libsodium and most other bindings and wrappers of libsodium and nacl.
Creates a fresh random keypair. signPk is the public key andsignSk is the secret key.
k = nacl.crypto_sign_keypair();
m = nacl.encode_utf8("message");
signed_m = nacl.crypto_sign(m, k.signSk);
m1 = nacl.crypto_sign_open(signed_m, k.signPk);
"message" === nacl.decode_utf8(m1); // always true
Produces a signature-wrapped version of msgBin.
Verifies the signature on the given packetBin, and if it is valid,
extracts the carried message and returns it. If the signature could
not be verified, returns null.
WARNING: Experimental. Produces a "detached" signature that,
unlike crypto_sign, excludes the actual message body. The result can
be used with crypto_sign_verify_detached.
The returned detached signature will be nacl.crypto_sign_BYTES in
length.
WARNING: Experimental. Given a "detached" signature fromcrypto_sign_detached, along with the original message and the
signer's public signing key, returns true if the signature is valid,
and false otherwise.
WARNING: Experimental
If you see yourself wanting to use these, you will need to know why
PBKDF2 and
scrypt are of crucial
importance.
You might like to explore the use of these functions in tandem withscrypt.crypto_scrypt from
js-scrypt.
It is not generally safe to supply (for example) a user's passphrase
directly to these procedures without using PBKDF2, scrypt or something
similar beforehand.
Produces a signing keypair from its argument. A given binary input
will always produce the same keypair as output.
The input must be 32 bytes long. As
Brian Warner puts it,
"Ed25519 keys start life as a 32-byte (256-bit) uniformly random
binary seed" such as might be produced by sha256, or better yet,
PBKDF2 or scrypt.
Make sure to read and understand the warnings relating to passphrases,
PBKDF2 and scrypt at the beginning of this section.
Compatible with PyNaCl'scrypto_sign_keypair_fromseed and
racl's bytes->crypto-sign-keypair.
(Prior to v1.2.0, known as nacl.crypto_sign_keypair_from_seed.)
Produces an encrypted authenticated box keypair from its argument. A
given binary input will always produce the same keypair as output.
The input may be of any length. The input is hashed once with sha512,
and the first 32 bytes of the result are taken as the 32-byte secret
key, which is then passed to nacl.crypto_box_keypair_from_raw_sk.
Make sure to read and understand the warnings relating to passphrases,
PBKDF2 and scrypt at the beginning of this section.
Compatible with racl'sbytes->crypto-box-keypair.
(Prior to v1.2.0, known as nacl.crypto_box_keypair_from_seed.)
Produces an encrypted authenticated box keypair from its argument. A
given binary input will always produce the same keypair as output.
The input must be 32 bytes long, and could be a random 32-byte value,
or the output of sha256, or better yet, the output of PBKDF2 or
scrypt.
Make sure to read and understand the warnings relating to passphrases,
PBKDF2 and scrypt at the beginning of this section.
Compatible with racl'scrypto-box-sk->pk.
Expects two binaries, the first of lengthnacl.crypto_scalarmult_SCALARBYTES (representing an integer), and
the second of length nacl.crypto_scalarmult_BYTES (representing a
group element). The two are multiplied using the underlying NaClcrypto_scalarmult primitive, and the resultingnacl.crypto_scalarmult_BYTES-length group element binary is
returned.
As nacl.crypto_scalarmult, but multiplies thenacl.crypto_scalarmult_SCALARBYTES-length argument by a standard
group element, returning the result.
js-nacl is written by Tony Garnock-Jones
and is licensed under the MIT
license:
> Copyright © 2013-2018 Tony Garnock-Jones.
>
> Permission is hereby granted, free of charge, to any person
> obtaining a copy of this software and associated documentation files
> (the "Software"), to deal in the Software without restriction,
> including without limitation the rights to use, copy, modify, merge,
> publish, distribute, sublicense, and/or sell copies of the Software,
> and to permit persons to whom the Software is furnished to do so,
> subject to the following conditions:
>
> The above copyright notice and this permission notice shall be
> included in all copies or substantial portions of the Software.
>
> THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
> EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
> MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
> NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
> BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
> ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
> CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
> SOFTWARE.
js-nacl relies on libsodium, which is released under the
ISC license:
> Copyright (c) 2013-2018
> Frank Denis
>
> Permission to use, copy, modify, and/or 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.
libsodium in turn relies on NaCl itself, which is public domain code
by Daniel J. Bernstein and others.