use serde::{Deserialize, Serialize}; use sha1::{Digest, Sha1}; use std::collections::HashMap; use chrono::{DateTime, offset::Utc}; /// The body of the request for resources made to the rdsys backend #[derive(Serialize)] pub struct ResourceRequest { pub request_origin: String, pub resource_types: Vec, } /// Representation of a bridge resource #[derive(Deserialize, PartialEq, Eq, Debug)] pub struct Resource { pub r#type: String, pub blocked_in: HashMap, pub last_passed: DateTime, pub protocol: String, pub address: String, pub port: u16, pub fingerprint: String, #[serde(rename = "or-addresses")] pub or_addresses: Option>, pub distribution: String, pub flags: Option>, pub params: Option>, } impl Resource { /// get_uid creates a unique identifier of the resource from a hash of the fingerprint /// and bridge type. A similar process is used in rdsys /// https://gitlab.torproject.org/tpo/anti-censorship/rdsys/-/blob/main/pkg/usecases/resources/bridges.go#L99 /// however, the golang and rust implementations of crc64 lead to different hash values. /// The polynomial used for rust's crc64 package is: https://docs.rs/crc64/2.0.0/src/crc64/lib.rs.html#8 /// using "Jones" coefficients. Changing go's polynomial to match rust's still doesn't make the hashes the same. /// We use the get_uid in this case for an identifier in the distributor so as long as it is unique, it doesn't /// strictly need to match the value in rdsys' backend. pub fn get_uid(&self) -> Result { let hex_fingerprint = match hex::decode(self.fingerprint.clone()) { Ok(hex_fingerprint) => hex_fingerprint, Err(e) => return Err(e), }; let mut hasher = Sha1::new(); hasher.update(hex_fingerprint); let result_fingerprint = hasher.finalize(); let uid_string = self.r#type.clone() + &hex::encode_upper(result_fingerprint); Ok(crc64::crc64(0, uid_string.as_bytes())) } } /// A ResourceDiff holds information about new, changed, or pruned resources #[derive(Deserialize, PartialEq, Eq, Debug)] pub struct ResourceDiff { pub new: Option>>, pub changed: Option>>, pub gone: Option>>, pub full_update: bool, } #[cfg(test)] mod tests { use chrono::Utc; use super::*; #[test] fn serialize_resource_request() { let req = ResourceRequest { request_origin: String::from("https"), resource_types: vec![String::from("obfs2"), String::from("scramblesuit")], }; let json = serde_json::to_string(&req).unwrap(); assert_eq!( json, "{\"request_origin\":\"https\",\"resource_types\":[\"obfs2\",\"scramblesuit\"]}" ) } #[test] fn deserialize_resource() { let mut flags = HashMap::new(); flags.insert(String::from("fast"), true); flags.insert(String::from("stable"), true); let mut params = HashMap::new(); params.insert( String::from("password"), String::from("ABCDEFGHIJKLMNOPQRSTUVWXYZ234567"), ); let bridge = Resource { r#type: String::from("scramblesuit"), blocked_in: HashMap::new(), last_passed: "2023-05-30T14:20:28Z".parse::>().unwrap(), protocol: String::from("tcp"), address: String::from("216.117.3.62"), port: 63174, fingerprint: String::from("BE84A97D02130470A1C77839954392BA979F7EE1"), or_addresses: None, distribution: String::from("https"), flags: Some(flags), params: Some(params), }; let data = r#" { "type": "scramblesuit", "blocked_in": {}, "last_passed": "2023-05-30T14:20:28.000+00:00", "protocol": "tcp", "address": "216.117.3.62", "port": 63174, "fingerprint": "BE84A97D02130470A1C77839954392BA979F7EE1", "or-addresses": null, "distribution": "https", "flags": { "fast": true, "stable": true }, "params": { "password": "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567" } }"#; let res: Resource = serde_json::from_str(data).unwrap(); assert_eq!(bridge, res); } #[test] fn deserialize_resource_diff() { let data = r#" { "new": { "obfs2": [ { "type": "obfs2", "blocked_in": {}, "last_passed": "2023-05-30T11:42:28.000+07:00", "Location": null, "protocol": "tcp", "address": "176.247.216.207", "port": 42810, "fingerprint": "10282810115283F99ADE5CFE42D49644F45D715D", "or-addresses": null, "distribution": "https", "flags": { "fast": true, "stable": true, "running": true, "valid": true } }, { "type": "obfs2", "blocked_in": {}, "last_passed": "2023-05-30T12:20:28.000+07:00", "protocol": "tcp", "address": "133.69.16.145", "port": 58314, "fingerprint": "BE84A97D02130470A1C77839954392BA979F7EE1", "or-addresses": null, "distribution": "https", "flags": { "fast": true, "stable": true, "running": true, "valid": true } } ], "scramblesuit": [ { "type": "scramblesuit", "blocked_in": {}, "last_passed": "2023-05-30T14:20:28.000+07:00", "protocol": "tcp", "address": "216.117.3.62", "port": 63174, "fingerprint": "BE84A97D02130470A1C77839954392BA979F7EE1", "or-addresses": null, "distribution": "https", "flags": { "fast": true, "stable": true, "running": true, "valid": true }, "params": { "password": "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567" } } ] }, "changed": null, "gone": null, "full_update": true }"#; let diff: ResourceDiff = serde_json::from_str(data).unwrap(); assert_ne!(diff.new, None); assert_eq!(diff.changed, None); assert_eq!(diff.gone, None); assert_eq!(diff.full_update, true); if let Some(new) = diff.new { assert_eq!(new["obfs2"][0].r#type, "obfs2"); } } #[test] fn deserialize_empty_resource_diff() { let data = r#" { "new": null, "changed": null, "gone": null, "full_update": true }"#; let diff: ResourceDiff = serde_json::from_str(data).unwrap(); let empty_diff = ResourceDiff { new: None, changed: None, gone: None, full_update: true, }; assert_eq!(diff, empty_diff); } #[test] fn deserialize_empty_condensed_diff() { let data = "{\"new\": null,\"changed\": null,\"gone\": null,\"full_update\": true}"; let diff: ResourceDiff = serde_json::from_str(data).unwrap(); let empty_diff = ResourceDiff { new: None, changed: None, gone: None, full_update: true, }; assert_eq!(diff, empty_diff); } }