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dns_update/providers/
safedns.rs

1/*
2 * Copyright Stalwart Labs LLC See the COPYING
3 * file at the top-level directory of this distribution.
4 *
5 * Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 * https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 * <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
8 * option. This file may not be copied, modified, or distributed
9 * except according to those terms.
10 */
11
12use crate::utils::split_caa_value;
13use crate::utils::unquote_txt;
14use crate::{
15    CAARecord, DnsRecord, DnsRecordType, Error, IntoFqdn, MXRecord, SRVRecord,
16    http::{HttpClient, HttpClientBuilder},
17    utils::txt_chunks_to_text,
18};
19use serde::{Deserialize, Serialize};
20use std::time::Duration;
21
22const DEFAULT_API_ENDPOINT: &str = "https://api.ukfast.io/safedns/v1";
23const LIST_PAGE_SIZE: u32 = 200;
24
25#[derive(Clone)]
26pub struct SafeDnsProvider {
27    client: HttpClient,
28    endpoint: String,
29}
30
31#[derive(Serialize, Debug, Clone)]
32pub struct SafeDnsRecordPayload<'a> {
33    pub name: &'a str,
34    #[serde(rename = "type")]
35    pub record_type: &'a str,
36    pub content: String,
37    pub ttl: u32,
38    #[serde(skip_serializing_if = "Option::is_none")]
39    pub priority: Option<u16>,
40}
41
42#[derive(Deserialize, Debug, Clone)]
43pub struct SafeDnsRecord {
44    pub id: i64,
45    pub name: String,
46    #[serde(rename = "type")]
47    pub record_type: String,
48    #[serde(default)]
49    pub content: String,
50    #[serde(default)]
51    pub priority: Option<u16>,
52}
53
54#[derive(Deserialize, Debug)]
55pub struct ListRecordsResponse {
56    pub data: Vec<SafeDnsRecord>,
57    #[serde(default)]
58    pub meta: ListMeta,
59}
60
61#[derive(Deserialize, Debug, Default)]
62pub struct ListMeta {
63    #[serde(default)]
64    pub pagination: Pagination,
65}
66
67#[derive(Deserialize, Debug, Default)]
68pub struct Pagination {
69    #[serde(default)]
70    pub total_pages: u32,
71}
72
73#[derive(Deserialize, Debug)]
74pub struct AddRecordResponse {
75    #[allow(dead_code)]
76    pub data: SafeDnsRecord,
77}
78
79#[derive(Debug, Clone, PartialEq, Eq)]
80pub struct SafeDnsRecordContent {
81    pub record_type: &'static str,
82    pub content: String,
83    pub priority: Option<u16>,
84}
85
86impl SafeDnsProvider {
87    pub(crate) fn new(auth_token: impl AsRef<str>, timeout: Option<Duration>) -> Self {
88        let client = HttpClientBuilder::default()
89            .with_header("Authorization", auth_token.as_ref())
90            .with_timeout(timeout)
91            .build();
92        Self {
93            client,
94            endpoint: DEFAULT_API_ENDPOINT.to_string(),
95        }
96    }
97
98    #[cfg(test)]
99    pub(crate) fn with_endpoint(self, endpoint: impl AsRef<str>) -> Self {
100        Self {
101            endpoint: endpoint.as_ref().to_string(),
102            ..self
103        }
104    }
105
106    pub(crate) async fn set_rrset(
107        &self,
108        name: impl IntoFqdn<'_>,
109        record_type: DnsRecordType,
110        ttl: u32,
111        records: Vec<DnsRecord>,
112        origin: impl IntoFqdn<'_>,
113    ) -> crate::Result<()> {
114        reject_unsupported(record_type)?;
115        let fqdn = name.into_name().into_owned();
116        let zone = origin.into_name().into_owned();
117        let desired = build_contents(record_type, records)?;
118        let existing = self.list_at(&zone, &fqdn, record_type).await?;
119
120        let mut existing_pool: Vec<SafeDnsRecord> = existing;
121        let mut to_add: Vec<SafeDnsRecordContent> = Vec::new();
122
123        for content in desired {
124            if let Some(idx) = existing_pool
125                .iter()
126                .position(|r| record_matches(r, &content))
127            {
128                existing_pool.swap_remove(idx);
129            } else {
130                to_add.push(content);
131            }
132        }
133
134        for entry in existing_pool {
135            self.delete_record(&zone, entry.id).await?;
136        }
137        for content in to_add {
138            self.create_record(&zone, &fqdn, ttl, &content).await?;
139        }
140        Ok(())
141    }
142
143    pub(crate) async fn add_to_rrset(
144        &self,
145        name: impl IntoFqdn<'_>,
146        record_type: DnsRecordType,
147        ttl: u32,
148        records: Vec<DnsRecord>,
149        origin: impl IntoFqdn<'_>,
150    ) -> crate::Result<()> {
151        reject_unsupported(record_type)?;
152        if records.is_empty() {
153            return Ok(());
154        }
155        let fqdn = name.into_name().into_owned();
156        let zone = origin.into_name().into_owned();
157        let desired = build_contents(record_type, records)?;
158        let existing = self.list_at(&zone, &fqdn, record_type).await?;
159
160        for content in desired {
161            if existing.iter().any(|r| record_matches(r, &content)) {
162                continue;
163            }
164            self.create_record(&zone, &fqdn, ttl, &content).await?;
165        }
166        Ok(())
167    }
168
169    pub(crate) async fn remove_from_rrset(
170        &self,
171        name: impl IntoFqdn<'_>,
172        record_type: DnsRecordType,
173        records: Vec<DnsRecord>,
174        origin: impl IntoFqdn<'_>,
175    ) -> crate::Result<()> {
176        reject_unsupported(record_type)?;
177        if records.is_empty() {
178            return Ok(());
179        }
180        let fqdn = name.into_name().into_owned();
181        let zone = origin.into_name().into_owned();
182        let to_remove = build_contents(record_type, records)?;
183        let existing = self.list_at(&zone, &fqdn, record_type).await?;
184
185        for content in to_remove {
186            if let Some(entry) = existing.iter().find(|r| record_matches(r, &content)) {
187                self.delete_record(&zone, entry.id).await?;
188            }
189        }
190        Ok(())
191    }
192
193    pub(crate) async fn list_rrset(
194        &self,
195        name: impl IntoFqdn<'_>,
196        record_type: DnsRecordType,
197        origin: impl IntoFqdn<'_>,
198    ) -> crate::Result<Vec<DnsRecord>> {
199        let fqdn = name.into_name().into_owned();
200        let zone = origin.into_name().into_owned();
201        let listed = self.list_at(&zone, &fqdn, record_type).await?;
202        listed
203            .into_iter()
204            .map(|r| safedns_record_to_dns_record(r, record_type))
205            .collect()
206    }
207
208    async fn list_at(
209        &self,
210        zone: &str,
211        name: &str,
212        record_type: DnsRecordType,
213    ) -> crate::Result<Vec<SafeDnsRecord>> {
214        let type_str = record_type.as_str();
215        let mut out: Vec<SafeDnsRecord> = Vec::new();
216        let mut page: u32 = 1;
217        loop {
218            let url = format!(
219                "{endpoint}/zones/{zone}/records?name:eq={name}&type:eq={type_str}&per_page={LIST_PAGE_SIZE}&page={page}",
220                endpoint = self.endpoint
221            );
222            let response: ListRecordsResponse = self.client.get(url).send_with_retry(3).await?;
223            let total_pages = response.meta.pagination.total_pages;
224            for record in response.data {
225                if record.name == name && record.record_type == type_str {
226                    out.push(record);
227                }
228            }
229            if total_pages <= page {
230                break;
231            }
232            page += 1;
233        }
234        Ok(out)
235    }
236
237    async fn create_record(
238        &self,
239        zone: &str,
240        name: &str,
241        ttl: u32,
242        content: &SafeDnsRecordContent,
243    ) -> crate::Result<()> {
244        let body = SafeDnsRecordPayload {
245            name,
246            record_type: content.record_type,
247            content: content.content.clone(),
248            ttl,
249            priority: content.priority,
250        };
251
252        self.client
253            .post(format!(
254                "{endpoint}/zones/{zone}/records",
255                endpoint = self.endpoint
256            ))
257            .with_body(&body)?
258            .send_with_retry::<serde_json::Value>(3)
259            .await
260            .map(|_| ())
261    }
262
263    async fn delete_record(&self, zone: &str, record_id: i64) -> crate::Result<()> {
264        self.client
265            .delete(format!(
266                "{endpoint}/zones/{zone}/records/{record_id}",
267                endpoint = self.endpoint
268            ))
269            .send_with_retry::<serde_json::Value>(3)
270            .await
271            .map(|_| ())
272    }
273}
274
275fn reject_unsupported(record_type: DnsRecordType) -> crate::Result<()> {
276    if record_type == DnsRecordType::TLSA {
277        return Err(Error::Unsupported(
278            "TLSA records are not supported by SafeDNS".to_string(),
279        ));
280    }
281    Ok(())
282}
283
284fn build_contents(
285    expected_type: DnsRecordType,
286    records: Vec<DnsRecord>,
287) -> crate::Result<Vec<SafeDnsRecordContent>> {
288    let mut out = Vec::with_capacity(records.len());
289    for record in records {
290        if record.as_type() != expected_type {
291            return Err(Error::Api(format!(
292                "RRSet record type mismatch: expected {}, got {}",
293                expected_type.as_str(),
294                record.as_type().as_str(),
295            )));
296        }
297        out.push(SafeDnsRecordContent::try_from(record)?);
298    }
299    Ok(out)
300}
301
302fn record_matches(record: &SafeDnsRecord, content: &SafeDnsRecordContent) -> bool {
303    record.record_type == content.record_type
304        && record.content == content.content
305        && record.priority == content.priority
306}
307
308fn safedns_record_to_dns_record(
309    record: SafeDnsRecord,
310    record_type: DnsRecordType,
311) -> crate::Result<DnsRecord> {
312    match record_type {
313        DnsRecordType::A => record
314            .content
315            .parse()
316            .map(DnsRecord::A)
317            .map_err(|e| Error::Parse(format!("invalid A content {}: {e}", record.content))),
318        DnsRecordType::AAAA => record
319            .content
320            .parse()
321            .map(DnsRecord::AAAA)
322            .map_err(|e| Error::Parse(format!("invalid AAAA content {}: {e}", record.content))),
323        DnsRecordType::CNAME => Ok(DnsRecord::CNAME(record.content)),
324        DnsRecordType::NS => Ok(DnsRecord::NS(record.content)),
325        DnsRecordType::MX => Ok(DnsRecord::MX(MXRecord {
326            exchange: record.content,
327            priority: record.priority.unwrap_or(0),
328        })),
329        DnsRecordType::TXT => Ok(DnsRecord::TXT(unquote_txt(&record.content))),
330        DnsRecordType::SRV => parse_srv(&record.content, record.priority.unwrap_or(0)),
331        DnsRecordType::TLSA => Err(Error::Unsupported(
332            "TLSA records are not supported by SafeDNS".to_string(),
333        )),
334        DnsRecordType::CAA => parse_caa(&record.content),
335    }
336}
337
338fn parse_srv(content: &str, priority: u16) -> crate::Result<DnsRecord> {
339    let parts: Vec<&str> = content.split_whitespace().collect();
340    if parts.len() != 3 {
341        return Err(Error::Parse(format!(
342            "invalid SRV content (expected `<weight> <port> <target>`): {content}"
343        )));
344    }
345    let weight: u16 = parts[0]
346        .parse()
347        .map_err(|e| Error::Parse(format!("invalid SRV weight {}: {e}", parts[0])))?;
348    let port: u16 = parts[1]
349        .parse()
350        .map_err(|e| Error::Parse(format!("invalid SRV port {}: {e}", parts[1])))?;
351    Ok(DnsRecord::SRV(SRVRecord {
352        priority,
353        weight,
354        port,
355        target: parts[2].to_string(),
356    }))
357}
358
359fn parse_caa(content: &str) -> crate::Result<DnsRecord> {
360    let trimmed = content.trim();
361    let (flags_str, rest) = trimmed
362        .split_once(char::is_whitespace)
363        .ok_or_else(|| Error::Parse(format!("invalid CAA content: {content}")))?;
364    let (tag, value_part) = rest
365        .trim_start()
366        .split_once(char::is_whitespace)
367        .ok_or_else(|| Error::Parse(format!("invalid CAA content: {content}")))?;
368    let flags: u8 = flags_str
369        .parse()
370        .map_err(|e| Error::Parse(format!("invalid CAA flags {flags_str}: {e}")))?;
371    let value = value_part
372        .trim()
373        .trim_start_matches('"')
374        .trim_end_matches('"')
375        .to_string();
376    let issuer_critical = flags & 0x80 != 0;
377    match tag.trim() {
378        "issue" => {
379            let (name, options) = split_caa_value(&value);
380            Ok(DnsRecord::CAA(CAARecord::Issue {
381                issuer_critical,
382                name,
383                options,
384            }))
385        }
386        "issuewild" => {
387            let (name, options) = split_caa_value(&value);
388            Ok(DnsRecord::CAA(CAARecord::IssueWild {
389                issuer_critical,
390                name,
391                options,
392            }))
393        }
394        "iodef" => Ok(DnsRecord::CAA(CAARecord::Iodef {
395            issuer_critical,
396            url: value,
397        })),
398        other => Err(Error::Parse(format!("unknown CAA tag: {other}"))),
399    }
400}
401
402impl TryFrom<DnsRecord> for SafeDnsRecordContent {
403    type Error = Error;
404
405    fn try_from(record: DnsRecord) -> Result<Self, Self::Error> {
406        match record {
407            DnsRecord::A(addr) => Ok(SafeDnsRecordContent {
408                record_type: "A",
409                content: addr.to_string(),
410                priority: None,
411            }),
412            DnsRecord::AAAA(addr) => Ok(SafeDnsRecordContent {
413                record_type: "AAAA",
414                content: addr.to_string(),
415                priority: None,
416            }),
417            DnsRecord::CNAME(target) => Ok(SafeDnsRecordContent {
418                record_type: "CNAME",
419                content: target,
420                priority: None,
421            }),
422            DnsRecord::NS(target) => Ok(SafeDnsRecordContent {
423                record_type: "NS",
424                content: target,
425                priority: None,
426            }),
427            DnsRecord::MX(mx) => Ok(SafeDnsRecordContent {
428                record_type: "MX",
429                content: mx.exchange,
430                priority: Some(mx.priority),
431            }),
432            DnsRecord::TXT(text) => {
433                let mut buf = String::new();
434                txt_chunks_to_text(&mut buf, &text, " ");
435                Ok(SafeDnsRecordContent {
436                    record_type: "TXT",
437                    content: buf,
438                    priority: None,
439                })
440            }
441            DnsRecord::SRV(srv) => Ok(SafeDnsRecordContent {
442                record_type: "SRV",
443                content: format!("{} {} {}", srv.weight, srv.port, srv.target),
444                priority: Some(srv.priority),
445            }),
446            DnsRecord::TLSA(_) => Err(Error::Unsupported(
447                "TLSA records are not supported by SafeDNS".to_string(),
448            )),
449            DnsRecord::CAA(caa) => {
450                let (flags, tag, value) = caa.decompose();
451                Ok(SafeDnsRecordContent {
452                    record_type: "CAA",
453                    content: format!("{flags} {tag} \"{value}\""),
454                    priority: None,
455                })
456            }
457        }
458    }
459}