1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129

use rocket::{
    fairing::{Fairing, Info, Kind},
    http::Status,
    request::{self, FromRequest, Request},
    Data,
};

use casbin::prelude::*;
use casbin::{CachedEnforcer, CoreApi, Result as CasbinResult};
use parking_lot::RwLock;
use std::sync::Arc;

pub struct CasbinVals {
    pub subject: Option<String>,
    pub domain: Option<String>,
}

impl CasbinVals {
    pub fn new(subject: Option<String>, domain: Option<String>) -> CasbinVals {
        CasbinVals { subject, domain }
    }
}

#[derive(Clone)]
pub struct CasbinGuard(Option<Status>);

impl<'a, 'r> FromRequest<'a, 'r> for CasbinGuard {
    type Error = ();

    fn from_request(request: &'a Request<'r>) -> request::Outcome<CasbinGuard, ()> {
        match *request.local_cache(|| CasbinGuard(Status::from_code(0))) {
            CasbinGuard(Some(Status::Ok)) => {
                request::Outcome::Success(CasbinGuard(Some(Status::Ok)))
            }
            CasbinGuard(Some(err_status)) => request::Outcome::Failure((err_status, ())),
            _ => request::Outcome::Failure((Status::BadGateway, ())),
        }
    }
}

#[derive(Clone)]
pub struct CasbinFairing {
    pub enforcer: Arc<RwLock<CachedEnforcer>>,
}

impl CasbinFairing {
    pub async fn new<M: TryIntoModel, A: TryIntoAdapter>(m: M, a: A) -> CasbinResult<Self> {
        let enforcer: CachedEnforcer = CachedEnforcer::new(m, a).await?;
        Ok(CasbinFairing {
            enforcer: Arc::new(RwLock::new(enforcer)),
        })
    }

    pub fn get_enforcer(&mut self) -> Arc<RwLock<CachedEnforcer>> {
        self.enforcer.clone()
    }

    pub fn set_enforcer(e: Arc<RwLock<CachedEnforcer>>) -> CasbinFairing {
        CasbinFairing { enforcer: e }
    }
}

impl Fairing for CasbinFairing {
    fn info(&self) -> Info {
        Info {
            name: "Casbin Fairing",
            kind: Kind::Request | Kind::Response,
        }
    }

    fn on_request(&self, request: &mut Request, _data: &Data) {
        let cloned_enforce = self.enforcer.clone();
        let path = request.uri().path().to_owned();
        let action = request.method().as_str().to_owned();

        let (subject, domain) = match request.local_cache(|| CasbinVals {
            subject: None,
            domain: None,
        }) {
            CasbinVals {
                subject: Some(x),
                domain: Some(y),
            } => (Some(x.to_owned()), Some(y.to_owned())),
            CasbinVals {
                subject: Some(x),
                domain: None,
            } => (Some(x.to_owned()), None),
            _ => (None, None),
        };

        if let Some(subject) = subject {
            if let Some(domain) = domain {
                let mut lock = cloned_enforce.write();
                match lock.enforce_mut(vec![subject, domain, path, action]) {
                    Ok(true) => {
                        drop(lock);
                        request.local_cache(|| CasbinGuard(Some(Status::Ok)));
                    }
                    Ok(false) => {
                        drop(lock);
                        request.local_cache(|| CasbinGuard(Some(Status::Forbidden)));
                    }
                    Err(_) => {
                        drop(lock);
                        request.local_cache(|| CasbinGuard(Some(Status::BadGateway)));
                    }
                };
            } else {
                let mut lock = cloned_enforce.write();
                match lock.enforce_mut(vec![subject, path, action]) {
                    Ok(true) => {
                        drop(lock);
                        request.local_cache(|| CasbinGuard(Some(Status::Ok)));
                    }
                    Ok(false) => {
                        drop(lock);
                        request.local_cache(|| CasbinGuard(Some(Status::Forbidden)));
                    }
                    Err(_) => {
                        drop(lock);
                        request.local_cache(|| CasbinGuard(Some(Status::BadGateway)));
                    }
                };
            }
        } else {
            request.local_cache(|| CasbinGuard(Some(Status::BadGateway)));
        }
    }
}