lox_cli/src/client_lib.rs

use async_trait::async_trait;
use curve25519_dalek::scalar::Scalar;
use lox_library::bridge_table::BridgeLine;
use lox_library::bridge_table::EncryptedBucket;
use lox_library::proto::*;
use lox_library::scalar_u32;
use lox_library::IssuerPubKey;
use lox_library::OPENINV_LENGTH;
use lox_utils::EncBridgeTable;
use serde::{Deserialize, Serialize};
use serde_with::serde_as;
use std::collections::HashMap;
use std::time::Duration;

// used for testing function
use std::io::Write;

// provides a generic way to make network requests
#[async_trait]
pub trait Networking {
    async fn request(&self, endpoint: String, body: Vec<u8>) -> Vec<u8>;
}

// From https://gitlab.torproject.org/onyinyang/lox-server/-/blob/main/src/main.rs
// TODO: Move this to main Lox library?
#[serde_as]
#[derive(Serialize, Deserialize)]
pub struct Invite {
    #[serde_as(as = "[_; OPENINV_LENGTH]")]
    invite: [u8; OPENINV_LENGTH],
}

// Helper functions to get public keys from vector
pub fn get_lox_pub(lox_auth_pubkeys: &Vec<IssuerPubKey>) -> &IssuerPubKey {
    &lox_auth_pubkeys[0]
}

pub fn get_migration_pub(lox_auth_pubkeys: &Vec<IssuerPubKey>) -> &IssuerPubKey {
    &lox_auth_pubkeys[1]
}

pub fn get_migrationkey_pub(lox_auth_pubkeys: &Vec<IssuerPubKey>) -> &IssuerPubKey {
    &lox_auth_pubkeys[2]
}

pub fn get_reachability_pub(lox_auth_pubkeys: &Vec<IssuerPubKey>) -> &IssuerPubKey {
    &lox_auth_pubkeys[3]
}

pub fn get_invitation_pub(lox_auth_pubkeys: &Vec<IssuerPubKey>) -> &IssuerPubKey {
    &lox_auth_pubkeys[4]
}

// Helper function to get credential trust level as i8
// (Note that this value should only be 0-4)
pub fn get_cred_trust_level(cred: &lox_library::cred::Lox) -> i8 {
    let trust_levels: [Scalar; 5] = [
        Scalar::zero(),
        Scalar::one(),
        Scalar::from(2u64),
        Scalar::from(3u64),
        Scalar::from(4u8),
    ];
    for i in 0..trust_levels.len() {
        if cred.trust_level == trust_levels[i] {
            return i.try_into().unwrap();
        }
    }
    -1
}

// Helper function to check if credential is eligible for
// promotion from level 0 to 1
pub async fn eligible_for_trust_promotion(
    net: &dyn Networking,
    cred: &lox_library::cred::Lox,
) -> bool {
    let level_since: u32 = match scalar_u32(&cred.level_since) {
        Some(v) => v,
        None => return false,
    };
    get_cred_trust_level(cred) == 0
        && level_since + lox_library::proto::trust_promotion::UNTRUSTED_INTERVAL
            <= get_today(net).await
}

// Helper function to check if credential is eligible for
// level up from level 1+
pub async fn eligible_for_level_up(net: &dyn Networking, cred: &lox_library::cred::Lox) -> bool {
    let level_since: u32 = match scalar_u32(&cred.level_since) {
        Some(v) => v,
        None => return false,
    };
    let trust_level: usize = get_cred_trust_level(cred).try_into().unwrap();
    trust_level > 0
        && level_since + lox_library::proto::level_up::LEVEL_INTERVAL[trust_level]
            <= get_today(net).await
}

// Get current date from Lox Auth
pub async fn get_today(net: &dyn Networking) -> u32 {
    let resp = net.request("/today".to_string(), [].to_vec()).await;
    let today: u32 = serde_json::from_slice(&resp).unwrap();
    today
}

// Download Lox Auth pubkeys
pub async fn get_lox_auth_keys(net: &dyn Networking) -> Vec<IssuerPubKey> {
    let resp = net.request("/pubkeys".to_string(), [].to_vec()).await;
    let lox_auth_pubkeys: Vec<IssuerPubKey> = serde_json::from_slice(&resp).unwrap();
    lox_auth_pubkeys
}

// Get encrypted bridge table
pub async fn get_reachability_credential(net: &dyn Networking) -> HashMap<u32, EncryptedBucket> {
    let resp = net.request("/reachability".to_string(), [].to_vec()).await;
    let reachability_cred: EncBridgeTable = serde_json::from_slice(&resp).unwrap();
    reachability_cred.etable
}

// Get an open invitation
pub async fn get_open_invitation(net: &dyn Networking) -> [u8; OPENINV_LENGTH] {
    let resp = net.request("/invite".to_string(), [].to_vec()).await;
    let open_invite: [u8; OPENINV_LENGTH] = serde_json::from_slice::<Invite>(&resp).unwrap().invite;
    open_invite
}

// Get a Lox Credential from an open invitation
pub async fn get_lox_credential(
    net: &dyn Networking,
    open_invite: &[u8; OPENINV_LENGTH],
    lox_pub: &IssuerPubKey,
) -> (lox_library::cred::Lox, BridgeLine) {
    let (req, state) = open_invite::request(&open_invite);
    let encoded_req: Vec<u8> = serde_json::to_vec(&req).unwrap();
    let encoded_resp = net.request("/openreq".to_string(), encoded_req).await;
    let decoded_resp: open_invite::Response = serde_json::from_slice(&encoded_resp).unwrap();
    let (cred, bridgeline) = open_invite::handle_response(state, decoded_resp, &lox_pub).unwrap();
    (cred, bridgeline)
}

// Get a migration credential to migrate to higher trust
pub async fn trust_promotion(
    net: &dyn Networking,
    lox_cred: &lox_library::cred::Lox,
    lox_pub: &IssuerPubKey,
) -> lox_library::cred::Migration {
    let (req, state) = trust_promotion::request(&lox_cred, &lox_pub, get_today(net).await).unwrap();
    let encoded_req: Vec<u8> = serde_json::to_vec(&req).unwrap();
    let encoded_resp = net.request("/trustpromo".to_string(), encoded_req).await;
    let decoded_resp: trust_promotion::Response = serde_json::from_slice(&encoded_resp).unwrap();
    let migration_cred = trust_promotion::handle_response(state, decoded_resp).unwrap();
    migration_cred
}

// Promote from untrusted (trust level 0) to trusted (trust level 1)
pub async fn trust_migration(
    net: &dyn Networking,
    lox_cred: &lox_library::cred::Lox,
    migration_cred: &lox_library::cred::Migration,
    lox_pub: &IssuerPubKey,
    migration_pub: &IssuerPubKey,
) -> lox_library::cred::Lox {
    let (req, state) =
        migration::request(lox_cred, migration_cred, lox_pub, migration_pub).unwrap();
    let encoded_req: Vec<u8> = serde_json::to_vec(&req).unwrap();
    let encoded_resp = net.request("/trustmig".to_string(), encoded_req).await;
    let decoded_resp: migration::Response = serde_json::from_slice(&encoded_resp).unwrap();
    let cred = migration::handle_response(state, decoded_resp, lox_pub).unwrap();
    cred
}

// Increase trust from at least level 1 to higher levels
pub async fn level_up(
    net: &dyn Networking,
    lox_cred: &lox_library::cred::Lox,
    encbuckets: &HashMap<u32, EncryptedBucket>,
    lox_pub: &IssuerPubKey,
    reachability_pub: &IssuerPubKey,
) -> lox_library::cred::Lox {
    // Read the bucket in the credential to get today's Bucket
    // Reachability credential
    let (id, key) = lox_library::bridge_table::from_scalar(lox_cred.bucket).unwrap();
    let bucket = lox_library::bridge_table::BridgeTable::decrypt_bucket(
        id,
        &key,
        &encbuckets.get(&id).unwrap(),
    )
    .unwrap();
    let reachcred = bucket.1.unwrap();

    // Use the Bucket Reachability credential to advance to the next
    // level
    let (req, state) = level_up::request(
        lox_cred,
        &reachcred,
        lox_pub,
        reachability_pub,
        get_today(net).await,
    )
    .unwrap();
    let encoded_req: Vec<u8> = serde_json::to_vec(&req).unwrap();
    let encoded_resp = net.request("/levelup".to_string(), encoded_req).await;
    let decoded_resp: level_up::Response = serde_json::from_slice(&encoded_resp).unwrap();
    let cred = level_up::handle_response(state, decoded_resp, lox_pub).unwrap();
    cred
}

// Request an Invitation credential to give to a friend
pub async fn issue_invite(
    net: &dyn Networking,
    lox_cred: &lox_library::cred::Lox,
    encbuckets: &HashMap<u32, EncryptedBucket>,
    lox_pub: &IssuerPubKey,
    reachability_pub: &IssuerPubKey,
    invitation_pub: &IssuerPubKey,
) -> (lox_library::cred::Lox, lox_library::cred::Invitation) {
    // Read the bucket in the credential to get today's Bucket
    // Reachability credential

    let (id, key) = lox_library::bridge_table::from_scalar(lox_cred.bucket).unwrap();
    let bucket = lox_library::bridge_table::BridgeTable::decrypt_bucket(
        id,
        &key,
        &encbuckets.get(&id).unwrap(),
    )
    .unwrap();
    let reachcred = bucket.1.unwrap();

    let (req, state) = issue_invite::request(
        lox_cred,
        &reachcred,
        lox_pub,
        reachability_pub,
        get_today(net).await,
    )
    .unwrap();
    let encoded_req: Vec<u8> = serde_json::to_vec(&req).unwrap();
    let encoded_resp = net.request("/issueinvite".to_string(), encoded_req).await;
    let decoded_resp: issue_invite::Response = serde_json::from_slice(&encoded_resp).unwrap();
    let (cred, invite) =
        issue_invite::handle_response(state, decoded_resp, lox_pub, invitation_pub).unwrap();
    (cred, invite)
}

// Redeem an Invitation credential to start at trust level 1
pub async fn redeem_invite(
    net: &dyn Networking,
    invite: &lox_library::cred::Invitation,
    lox_pub: &IssuerPubKey,
    invitation_pub: &IssuerPubKey,
) -> lox_library::cred::Lox {
    let (req, state) =
        redeem_invite::request(invite, invitation_pub, get_today(net).await).unwrap();
    let encoded_req: Vec<u8> = serde_json::to_vec(&req).unwrap();
    let encoded_resp = net.request("/redeem".to_string(), encoded_req).await;
    let decoded_resp: redeem_invite::Response = serde_json::from_slice(&encoded_resp).unwrap();
    let cred = redeem_invite::handle_response(state, decoded_resp, lox_pub).unwrap();
    cred
}

// Check for a migration credential to move to a new bucket
pub async fn check_blockage(
    net: &dyn Networking,
    lox_cred: &lox_library::cred::Lox,
    lox_pub: &IssuerPubKey,
) -> lox_library::cred::Migration {
    let (req, state) = check_blockage::request(lox_cred, lox_pub).unwrap();
    let encoded_req: Vec<u8> = serde_json::to_vec(&req).unwrap();
    let encoded_resp = net.request("/checkblockage".to_string(), encoded_req).await;
    let decoded_resp: check_blockage::Response = serde_json::from_slice(&encoded_resp).unwrap();
    let migcred = check_blockage::handle_response(state, decoded_resp).unwrap();
    migcred
}

// Migrate to a new bucket (must be level >= 3)
pub async fn blockage_migration(
    net: &dyn Networking,
    lox_cred: &lox_library::cred::Lox,
    migcred: &lox_library::cred::Migration,
    lox_pub: &IssuerPubKey,
    migration_pub: &IssuerPubKey,
) -> lox_library::cred::Lox {
    let (req, state) =
        blockage_migration::request(lox_cred, migcred, lox_pub, migration_pub).unwrap();
    let encoded_req: Vec<u8> = serde_json::to_vec(&req).unwrap();
    let encoded_resp = net
        .request("/blockagemigration".to_string(), encoded_req)
        .await;
    let decoded_resp: blockage_migration::Response = serde_json::from_slice(&encoded_resp).unwrap();
    let cred = blockage_migration::handle_response(state, decoded_resp, lox_pub).unwrap();
    cred
}

// Advance days on server (ONLY FOR TESTING)
pub async fn advance_days(net: &dyn Networking, days: u16) -> u32 {
    let resp = net
        .request(
            "/advancedays".to_string(),
            serde_json::to_vec(&days).unwrap(),
        )
        .await;
    let today: u32 = serde_json::from_slice(&resp).unwrap();
    today
}