## Zig-paseto 

A PASETO (Platform-Agnostic SEcurity TOkens) library for zig.


### Env

 - Zig >= 0.16.0


### What is PASETO?

PASETO (Platform-Agnostic SEcurity TOkens) is a specification and reference implementation
for secure stateless tokens.


### Key Differences between PASETO and JWT

Unlike JSON Web Tokens (JWT), which gives developers more than enough rope with which to
hang themselves, PASETO only allows secure operations. JWT gives you "algorithm agility",
PASETO gives you "versioned protocols". It's incredibly unlikely that you'll be able to
use PASETO in [an insecure way](https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries).


### Adding zig-paseto as a dependency

Add the dependency to your project:

```sh
zig fetch --save=zig-paseto git+https://github.com/deatil/zig-paseto#main
```

or use local path to add dependency at `build.zig.zon` file

```zig
.{
    .dependencies = .{
        .@"zig-paseto" = .{
            .path = "./lib/zig-paseto",
        },
        ...
    }
}
```

And the following to your `build.zig` file:

```zig
const zig_paseto_dep = b.dependency("zig-paseto", .{});
exe.root_module.addImport("zig-paseto", zig_paseto_dep.module("zig-paseto"));
```

The `zig-paseto` structure can be imported in your application with:

```zig
const paseto = @import("zig-paseto");
```


### Get Starting

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

const paseto = @import("zig-paseto");

pub fn main(init: std.process.Init) !void {
    _ = init;

    const alloc = std.heap.page_allocator;

    const key = "707172737475767778797a7b7c7d7e7f808182838485868788898a8b8c8d8e8f";

    var buf: [32]u8 = undefined;
    const k = try std.fmt.hexToBytes(&buf, key);

    const m = "{\"data\":\"this is a signed message\",\"exp\":\"2022-01-01T00:00:00+00:00\"}";
    const f = "{\"kid\":\"zVhMiPBP9fRf2snEcT7gFTioeA9COcNy9DfgL1W60haN\"}";
    const i = "{\"test-vector\":\"4-S-3\"}";

    var e = paseto.V4Local.init(alloc);
    defer e.deinit();

    try e.withMessage(m);
    try e.withFooter(f);
    try e.withImplicit(i);

    var prng = std.Random.DefaultPrng.init(1234);

    const token = try e.encode(prng.random(), k);
    defer alloc.free(token);
    
    // output: 
    // make paseto token: v4.local.G-ToOUO6A-LGTVrBKiVn7najk-XOBR2a4olurkkWrLgM9sKOf6tNlMpKbSZpI70E5MzgdnWq6yplehnR2VeLR4VTmGMZYDI0VMotPJpKJeBuS7xDoCsm8z_5wA9af2ZtTfrlMY5ErELyiqx5pqdVAzSBP9ZM6-Qxo4oHTnWAqjENeOHdYA.eyJraWQiOiJ6VmhNaVBCUDlmUmYyc25FY1Q3Z0ZUaW9lQTlDT2NOeTlEZmdMMVc2MGhhTiJ9
    std.debug.print("make paseto token: {s} \n", .{token});

    // ====================

    // parse token
    var p = paseto.V4Local.init(alloc);
    defer p.deinit();

    try p.withImplicit(i);

    try p.decode(token, k);
    
    // output: 
    // message: this is a signed message
    const message = try p.getMessage();
    defer message.deinit();
    std.debug.print("message: {s} \n", .{message.value.object.get("data").?.string});
}
~~~


### Encode Methods

The PASETO library have encode methods:

 - `v1.local`: paseto.V1Local
 - `v1.public`: paseto.V1Public

 - `v2.local`: paseto.V2Local
 - `v2.public`: paseto.V2Public

 - `v3.local`: paseto.V3Local
 - `v3.public`: paseto.V3Public

 - `v4.local`: paseto.V4Local
 - `v4.public`: paseto.V4Public


### LICENSE

*  The library LICENSE is `Apache2`, using the library need keep the LICENSE.


### Copyright

*  Copyright deatil(https://github.com/deatil).