gossan-subdomain 0.3.3

//! Greynoise subdomain source.
use gossan_core::{Config, DiscoverySource, DomainTarget, Target};
use crate::sources::{SubdomainSource, SourceRate};
use async_trait::async_trait;
use governor::DefaultDirectRateLimiter;

pub struct Greynoise;

#[async_trait]
impl SubdomainSource for Greynoise {
    fn name(&self) -> &'static str { "greynoise" }
    fn requires_api_key(&self) -> bool { true }
    fn api_key_name(&self) -> &'static str { "GREYNOISE_API_KEY" }
    fn rate_limit(&self) -> SourceRate { SourceRate::per_second(1) }
    fn discovery_source(&self) -> DiscoverySource { DiscoverySource::PassiveDns }

    async fn query(
        &self,
        domain: &str,
        config: &Config,
        client: &reqwest::Client,
        limiter: &DefaultDirectRateLimiter,
    ) -> anyhow::Result<Vec<Target>> {
        
        let Some(key) = crate::sources::get_api_key(config, "greynoise", "GREYNOISE_API_KEY") else {
            return Ok(vec![]);
        };

        let url = format!("https://api.greynoise.io/v3/community/{}", domain);
        limiter.until_ready().await;
        let resp = client
            .get(&url)
            .header("key", key)
            .send()
            .await?
            .error_for_status()?;
        let max_size = config.max_response_size;
        let bytes = gossan_core::read_response_limited(resp, max_size).await?;
        let mut seen = std::collections::HashSet::new();
        let domain_lower = domain.to_lowercase();
        
        let arr: Vec<String> = serde_json::from_slice(&bytes)?;
        for item in arr {
            let candidate = item.trim().trim_start_matches("*.").to_lowercase();
            if !candidate.contains('*') && crate::is_subdomain_of(&candidate, &domain_lower) {
                seen.insert(candidate);
            }
        }

        Ok(seen.into_iter().map(|d| Target::Domain(DomainTarget {
            domain: d,
            source: DiscoverySource::PassiveDns,
        })).collect())
    }
}