_ Git - dnssec-prover/blob - src/query.rs

   1 //! This module exposes utilities for building DNSSEC proofs by directly querying a recursive
   2 //! resolver.
   3
   4 use core::{cmp, ops};
   5 use alloc::vec;
   6 use alloc::vec::Vec;
   7
   8 #[cfg(feature = "std")]
   9 use std::net::{SocketAddr, TcpStream};
  10 #[cfg(feature = "std")]
  11 use std::io::{Read, Write, Error, ErrorKind};
  12
  13 #[cfg(feature = "tokio")]
  14 use tokio_crate::net::TcpStream as TokioTcpStream;
  15 #[cfg(feature = "tokio")]
  16 use tokio_crate::io::{AsyncReadExt, AsyncWriteExt};
  17
  18 use crate::rr::*;
  19 use crate::ser::*;
  20
  21 // In testing use a rather small buffer to ensure we hit the allocation paths sometimes. In
  22 // production, we should generally never actually need to go to heap as DNS messages are rarely
  23 // larger than a KiB or two.
  24 #[cfg(any(test, fuzzing))]
  25 const STACK_BUF_LIMIT: u16 = 32;
  26 #[cfg(not(any(test, fuzzing)))]
  27 const STACK_BUF_LIMIT: u16 = 2048;
  28
  29 /// A buffer for storing queries and responses.
  30 #[derive(Clone, PartialEq, Eq)]
  31 pub struct QueryBuf {
  32         buf: [u8; STACK_BUF_LIMIT as usize],
  33         heap_buf: Vec<u8>,
  34         len: u16,
  35 }
  36 impl QueryBuf {
  37         /// Generates a new buffer of the given length, consisting of all zeros.
  38         pub fn new_zeroed(len: u16) -> Self {
  39                 let heap_buf = if len > STACK_BUF_LIMIT { vec![0; len as usize] } else { Vec::new() };
  40                 Self {
  41                         buf: [0; STACK_BUF_LIMIT as usize],
  42                         heap_buf,
  43                         len
  44                 }
  45         }
  46         /// Extends the size of this buffer by appending the given slice.
  47         ///
  48         /// If the total length of this buffer exceeds [`u16::MAX`] after appending, the buffer's state
  49         /// is undefined, however pushing data beyond [`u16::MAX`] will not panic.
  50         pub fn extend_from_slice(&mut self, sl: &[u8]) {
  51                 let new_len = self.len.saturating_add(sl.len() as u16);
  52                 let was_heap = self.len > STACK_BUF_LIMIT;
  53                 let is_heap = new_len > STACK_BUF_LIMIT;
  54                 if was_heap != is_heap {
  55                         self.heap_buf = vec![0; new_len as usize];
  56                         self.heap_buf[..self.len as usize].copy_from_slice(&self.buf[..self.len as usize]);
  57                 }
  58                 let target = if is_heap {
  59                         self.heap_buf.resize(new_len as usize, 0);
  60                         &mut self.heap_buf[self.len as usize..]
  61                 } else {
  62                         &mut self.buf[self.len as usize..new_len as usize]
  63                 };
  64                 target.copy_from_slice(sl);
  65                 self.len = new_len;
  66         }
  67         /// Converts this query into its bytes on the heap
  68         pub fn into_vec(self) -> Vec<u8> {
  69                 if self.len > STACK_BUF_LIMIT {
  70                         self.heap_buf
  71                 } else {
  72                         self.buf[..self.len as usize].to_vec()
  73                 }
  74         }
  75 }
  76 impl ops::Deref for QueryBuf {
  77         type Target = [u8];
  78         fn deref(&self) -> &[u8] {
  79                 if self.len > STACK_BUF_LIMIT {
  80                         &self.heap_buf
  81                 } else {
  82                         &self.buf[..self.len as usize]
  83                 }
  84         }
  85 }
  86 impl ops::DerefMut for QueryBuf {
  87         fn deref_mut(&mut self) -> &mut [u8] {
  88                 if self.len > STACK_BUF_LIMIT {
  89                         &mut self.heap_buf
  90                 } else {
  91                         &mut self.buf[..self.len as usize]
  92                 }
  93         }
  94 }
  95
  96 // We don't care about transaction IDs as we're only going to accept signed data.
  97 // Further, if we're querying over DoH, the RFC says we SHOULD use a transaction ID of 0 here.
  98 const TXID: u16 = 0;
  99
 100 fn build_query(domain: &Name, ty: u16) -> QueryBuf {
 101         let mut query = QueryBuf::new_zeroed(0);
 102         query.extend_from_slice(&TXID.to_be_bytes());
 103         query.extend_from_slice(&[0x01, 0x20]); // Flags: Recursive, Authenticated Data
 104         query.extend_from_slice(&[0, 1, 0, 0, 0, 0, 0, 1]); // One question, One additional
 105         write_name(&mut query, domain);
 106         query.extend_from_slice(&ty.to_be_bytes());
 107         query.extend_from_slice(&1u16.to_be_bytes()); // INternet class
 108         query.extend_from_slice(&[0, 0, 0x29]); // . OPT
 109         query.extend_from_slice(&0u16.to_be_bytes()); // 0 UDP payload size
 110         query.extend_from_slice(&[0, 0]); // EDNS version 0
 111         query.extend_from_slice(&0x8000u16.to_be_bytes()); // Accept DNSSEC RRs
 112         query.extend_from_slice(&0u16.to_be_bytes()); // No additional data
 113         query
 114 }
 115
 116 #[cfg(fuzzing)]
 117 /// Read some input and parse it as if it came from a server, for fuzzing.
 118 pub fn fuzz_response(response: &[u8]) {
 119         let (mut proof, mut names) = (Vec::new(), Vec::new());
 120         let _ = handle_response(response, &mut proof, &mut names);
 121 }
 122
 123 fn handle_response(resp: &[u8], proof: &mut Vec<u8>, rrsig_key_names: &mut Vec<Name>) -> Result<u32, ()> {
 124         let mut read: &[u8] = resp;
 125         if read_u16(&mut read)? != TXID { return Err(()); }
 126         // 2 byte transaction ID
 127         let flags = read_u16(&mut read)?;
 128         if flags & 0b1000_0000_0000_0000 == 0 {
 129                 return Err(());
 130         }
 131         if flags & 0b0111_1010_0000_0111 != 0 {
 132                 return Err(());
 133         }
 134         if flags & 0b10_0000 == 0 {
 135                 return Err(());
 136         }
 137         let questions = read_u16(&mut read)?;
 138         if questions != 1 { return Err(()); }
 139         let answers = read_u16(&mut read)?;
 140         if answers == 0 { return Err(()); }
 141         let _authorities = read_u16(&mut read)?;
 142         let _additional = read_u16(&mut read)?;
 143
 144         for _ in 0..questions {
 145                 read_wire_packet_name(&mut read, resp)?;
 146                 read_u16(&mut read)?; // type
 147                 read_u16(&mut read)?; // class
 148         }
 149
 150         // Only read the answers (skip authorities and additional) as that's all we care about.
 151         let mut min_ttl = u32::MAX;
 152         for _ in 0..answers {
 153                 let (rr, ttl) = parse_wire_packet_rr(&mut read, &resp)?;
 154                 write_rr(&rr, ttl, proof);
 155                 min_ttl = cmp::min(min_ttl, ttl);
 156                 if let RR::RRSig(rrsig) = rr { rrsig_key_names.push(rrsig.key_name); }
 157         }
 158         Ok(min_ttl)
 159 }
 160
 161 #[cfg(fuzzing)]
 162 /// Read a stream of responses and handle them it as if they came from a server, for fuzzing.
 163 pub fn fuzz_proof_builder(mut response_stream: &[u8]) {
 164         let (mut builder, _) = ProofBuilder::new(&"example.com.".try_into().unwrap(), Txt::TYPE);
 165         while builder.awaiting_responses() {
 166                 let len = if let Ok(len) = read_u16(&mut response_stream) { len } else { return };
 167                 let mut buf = QueryBuf::new_zeroed(len);
 168                 if response_stream.len() < len as usize { return; }
 169                 buf.copy_from_slice(&response_stream[..len as usize]);
 170                 response_stream = &response_stream[len as usize..];
 171                 let _ = builder.process_response(&buf);
 172         }
 173         let _ = builder.finish_proof();
 174 }
 175
 176 const MAX_REQUESTS: usize = 10;
 177 /// A simple state machine which will generate a series of queries and process the responses until
 178 /// it has built a DNSSEC proof.
 179 ///
 180 /// A [`ProofBuilder`] driver starts with [`ProofBuilder::new`], fetching the state machine and
 181 /// initial query. As long as [`ProofBuilder::awaiting_responses`] returns true, responses should
 182 /// be read from the resolver. For each query response read from the DNS resolver,
 183 /// [`ProofBuilder::process_response`] should be called, and each fresh query returned should be
 184 /// sent to the resolver. Once [`ProofBuilder::awaiting_responses`] returns false,
 185 /// [`ProofBuilder::finish_proof`] should be called to fetch the resulting proof.
 186 pub struct ProofBuilder {
 187         proof: Vec<u8>,
 188         min_ttl: u32,
 189         dnskeys_requested: Vec<Name>,
 190         pending_queries: usize,
 191         queries_made: usize,
 192 }
 193
 194 impl ProofBuilder {
 195         /// Constructs a new [`ProofBuilder`] and an initial query to send to the recursive resolver to
 196         /// begin the proof building process.
 197         ///
 198         /// Given a correctly-functioning resolver the proof will ultimately be able to prove the
 199         /// contents of any records with the given `ty`pe at the given `name` (as long as the given
 200         /// `ty`pe is supported by this library).
 201         ///
 202         /// You can find constants for supported standard types in the [`crate::rr`] module.
 203         pub fn new(name: &Name, ty: u16) -> (ProofBuilder, QueryBuf) {
 204                 let initial_query = build_query(name, ty);
 205                 (ProofBuilder {
 206                         proof: Vec::new(),
 207                         min_ttl: u32::MAX,
 208                         dnskeys_requested: Vec::with_capacity(MAX_REQUESTS),
 209                         pending_queries: 1,
 210                         queries_made: 1,
 211                 }, initial_query)
 212         }
 213
 214         /// Returns true as long as further responses are expected from the resolver.
 215         ///
 216         /// As long as this returns true, responses should be read from the resolver and passed to
 217         /// [`Self::process_response`]. Once this returns false, [`Self::finish_proof`] should be used
 218         /// to (possibly) get the final proof.
 219         pub fn awaiting_responses(&self) -> bool {
 220                 self.pending_queries > 0 && self.queries_made <= MAX_REQUESTS
 221         }
 222
 223         /// Processes a query response from the recursive resolver, returning a list of new queries to
 224         /// send to the resolver.
 225         pub fn process_response(&mut self, resp: &QueryBuf) -> Result<Vec<QueryBuf>, ()> {
 226                 if self.pending_queries == 0 { return Err(()); }
 227
 228                 let mut rrsig_key_names = Vec::new();
 229                 let min_ttl = handle_response(&resp, &mut self.proof, &mut rrsig_key_names)?;
 230                 self.min_ttl = cmp::min(self.min_ttl, min_ttl);
 231                 self.pending_queries -= 1;
 232
 233                 rrsig_key_names.sort_unstable();
 234                 rrsig_key_names.dedup();
 235
 236                 let mut new_queries = Vec::with_capacity(2);
 237                 for key_name in rrsig_key_names.drain(..) {
 238                         if !self.dnskeys_requested.contains(&key_name) {
 239                                 new_queries.push(build_query(&key_name, DnsKey::TYPE));
 240                                 self.pending_queries += 1;
 241                                 self.queries_made += 1;
 242                                 self.dnskeys_requested.push(key_name.clone());
 243
 244                                 if key_name.as_str() != "." {
 245                                         new_queries.push(build_query(&key_name, DS::TYPE));
 246                                         self.pending_queries += 1;
 247                                         self.queries_made += 1;
 248                                 }
 249                         }
 250                 }
 251                 if self.queries_made <= MAX_REQUESTS {
 252                         Ok(new_queries)
 253                 } else {
 254                         Ok(Vec::new())
 255                 }
 256         }
 257
 258         /// Finalizes the proof, if one is available, and returns it as well as the TTL that should be
 259         /// used to cache the proof (i.e. the lowest TTL of all records which were used to build the
 260         /// proof).
 261         pub fn finish_proof(self) -> Result<(Vec<u8>, u32), ()> {
 262                 if self.pending_queries > 0 || self.queries_made > MAX_REQUESTS {
 263                         Err(())
 264                 } else {
 265                         Ok((self.proof, self.min_ttl))
 266                 }
 267         }
 268 }
 269
 270 #[cfg(feature = "std")]
 271 fn send_query(stream: &mut TcpStream, query: &[u8]) -> Result<(), Error> {
 272         stream.write_all(&(query.len() as u16).to_be_bytes())?;
 273         stream.write_all(&query)?;
 274         Ok(())
 275 }
 276
 277 #[cfg(feature = "tokio")]
 278 async fn send_query_async(stream: &mut TokioTcpStream, query: &[u8]) -> Result<(), Error> {
 279         stream.write_all(&(query.len() as u16).to_be_bytes()).await?;
 280         stream.write_all(&query).await?;
 281         Ok(())
 282 }
 283
 284 #[cfg(feature = "std")]
 285 fn read_response(stream: &mut TcpStream) -> Result<QueryBuf, Error> {
 286         let mut len_bytes = [0; 2];
 287         stream.read_exact(&mut len_bytes)?;
 288         let mut buf = QueryBuf::new_zeroed(u16::from_be_bytes(len_bytes));
 289         stream.read_exact(&mut buf)?;
 290         Ok(buf)
 291 }
 292
 293 #[cfg(feature = "tokio")]
 294 async fn read_response_async(stream: &mut TokioTcpStream) -> Result<QueryBuf, Error> {
 295         let mut len_bytes = [0; 2];
 296         stream.read_exact(&mut len_bytes).await?;
 297         let mut buf = QueryBuf::new_zeroed(u16::from_be_bytes(len_bytes));
 298         stream.read_exact(&mut buf).await?;
 299         Ok(buf)
 300 }
 301
 302 #[cfg(feature = "std")]
 303 macro_rules! build_proof_impl {
 304         ($stream: ident, $send_query: ident, $read_response: ident, $domain: expr, $ty: expr $(, $async_ok: tt)?) => { {
 305                 // We require the initial query to have already gone out, and assume our resolver will
 306                 // return any CNAMEs all the way to the final record in the response. From there, we just
 307                 // have to take any RRSIGs in the response and walk them up to the root. We do so
 308                 // iteratively, sending DNSKEY and DS lookups after every response, deduplicating requests
 309                 // using `dnskeys_requested`.
 310                 let (mut builder, initial_query) = ProofBuilder::new($domain, $ty);
 311                 $send_query(&mut $stream, &initial_query)
 312                         $(.await?; $async_ok)??; // Either await?; Ok(())?, or just ?
 313                 while builder.awaiting_responses() {
 314                         let response = $read_response(&mut $stream)
 315                                 $(.await?; $async_ok)??; // Either await?; Ok(())?, or just ?
 316                         let new_queries = builder.process_response(&response)
 317                                 .map_err(|()| Error::new(ErrorKind::Other, "Bad response"))?;
 318                         for query in new_queries {
 319                                 $send_query(&mut $stream, &query)
 320                                         $(.await?; $async_ok)??; // Either await?; Ok(())?, or just ?
 321                         }
 322                 }
 323
 324                 builder.finish_proof()
 325                         .map_err(|()| Error::new(ErrorKind::Other, "Too many requests required"))
 326         } }
 327 }
 328
 329 #[cfg(feature = "std")]
 330 fn build_proof(resolver: SocketAddr, domain: &Name, ty: u16) -> Result<(Vec<u8>, u32), Error> {
 331         let mut stream = TcpStream::connect(resolver)?;
 332         build_proof_impl!(stream, send_query, read_response, domain, ty)
 333 }
 334
 335 #[cfg(feature = "tokio")]
 336 async fn build_proof_async(resolver: SocketAddr, domain: &Name, ty: u16) -> Result<(Vec<u8>, u32), Error> {
 337         let mut stream = TokioTcpStream::connect(resolver).await?;
 338         build_proof_impl!(stream, send_query_async, read_response_async, domain, ty, { Ok::<(), Error>(()) })
 339 }
 340
 341 /// Builds a DNSSEC proof for an A record by querying a recursive resolver, returning the proof as
 342 /// well as the TTL for the proof provided by the recursive resolver.
 343 ///
 344 /// Note that this proof is NOT verified in any way, you need to use the [`crate::validation`]
 345 /// module to validate the records contained.
 346 #[cfg(feature = "std")]
 347 pub fn build_a_proof(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
 348         build_proof(resolver, domain, A::TYPE)
 349 }
 350
 351 /// Builds a DNSSEC proof for an AAAA record by querying a recursive resolver, returning the proof
 352 /// as well as the TTL for the proof provided by the recursive resolver.
 353 ///
 354 /// Note that this proof is NOT verified in any way, you need to use the [`crate::validation`]
 355 /// module to validate the records contained.
 356 #[cfg(feature = "std")]
 357 pub fn build_aaaa_proof(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
 358         build_proof(resolver, domain, AAAA::TYPE)
 359 }
 360
 361 /// Builds a DNSSEC proof for an TXT record by querying a recursive resolver, returning the proof
 362 /// as well as the TTL for the proof provided by the recursive resolver.
 363 ///
 364 /// Note that this proof is NOT verified in any way, you need to use the [`crate::validation`]
 365 /// module to validate the records contained.
 366 #[cfg(feature = "std")]
 367 pub fn build_txt_proof(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
 368         build_proof(resolver, domain, Txt::TYPE)
 369 }
 370
 371 /// Builds a DNSSEC proof for an TLSA record by querying a recursive resolver, returning the proof
 372 /// as well as the TTL for the proof provided by the recursive resolver.
 373 ///
 374 /// Note that this proof is NOT verified in any way, you need to use the [`crate::validation`]
 375 /// module to validate the records contained.
 376 #[cfg(feature = "std")]
 377 pub fn build_tlsa_proof(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
 378         build_proof(resolver, domain, TLSA::TYPE)
 379 }
 380
 381
 382 /// Builds a DNSSEC proof for an A record by querying a recursive resolver, returning the proof as
 383 /// well as the TTL for the proof provided by the recursive resolver.
 384 ///
 385 /// Note that this proof is NOT verified in any way, you need to use the [`crate::validation`]
 386 /// module to validate the records contained.
 387 #[cfg(feature = "tokio")]
 388 pub async fn build_a_proof_async(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
 389         build_proof_async(resolver, domain, A::TYPE).await
 390 }
 391
 392 /// Builds a DNSSEC proof for an AAAA record by querying a recursive resolver, returning the proof
 393 /// as well as the TTL for the proof provided by the recursive resolver.
 394 ///
 395 /// Note that this proof is NOT verified in any way, you need to use the [`crate::validation`]
 396 /// module to validate the records contained.
 397 #[cfg(feature = "tokio")]
 398 pub async fn build_aaaa_proof_async(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
 399         build_proof_async(resolver, domain, AAAA::TYPE).await
 400 }
 401
 402 /// Builds a DNSSEC proof for an TXT record by querying a recursive resolver, returning the proof
 403 /// as well as the TTL for the proof provided by the recursive resolver.
 404 ///
 405 /// Note that this proof is NOT verified in any way, you need to use the [`crate::validation`]
 406 /// module to validate the records contained.
 407 #[cfg(feature = "tokio")]
 408 pub async fn build_txt_proof_async(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
 409         build_proof_async(resolver, domain, Txt::TYPE).await
 410 }
 411
 412 /// Builds a DNSSEC proof for an TLSA record by querying a recursive resolver, returning the proof
 413 /// as well as the TTL for the proof provided by the recursive resolver.
 414 ///
 415 /// Note that this proof is NOT verified in any way, you need to use the [`crate::validation`]
 416 /// module to validate the records contained.
 417 #[cfg(feature = "tokio")]
 418 pub async fn build_tlsa_proof_async(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
 419         build_proof_async(resolver, domain, TLSA::TYPE).await
 420 }
 421
 422 #[cfg(all(feature = "validation", feature = "std", test))]
 423 mod tests {
 424         use super::*;
 425         use crate::validation::*;
 426
 427         use rand::seq::SliceRandom;
 428
 429         use std::net::ToSocketAddrs;
 430         use std::time::SystemTime;
 431
 432         #[test]
 433         fn test_cloudflare_txt_query() {
 434                 let sockaddr = "8.8.8.8:53".to_socket_addrs().unwrap().next().unwrap();
 435                 let query_name = "cloudflare.com.".try_into().unwrap();
 436                 let (proof, _) = build_txt_proof(sockaddr, &query_name).unwrap();
 437
 438                 let mut rrs = parse_rr_stream(&proof).unwrap();
 439                 rrs.shuffle(&mut rand::rngs::OsRng);
 440                 let verified_rrs = verify_rr_stream(&rrs).unwrap();
 441                 assert!(verified_rrs.verified_rrs.len() > 1);
 442
 443                 let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
 444                 assert!(verified_rrs.valid_from < now);
 445                 assert!(verified_rrs.expires > now);
 446         }
 447
 448         #[test]
 449         fn test_sha1_query() {
 450                 let sockaddr = "8.8.8.8:53".to_socket_addrs().unwrap().next().unwrap();
 451                 let query_name = "benthecarman.com.".try_into().unwrap();
 452                 let (proof, _) = build_a_proof(sockaddr, &query_name).unwrap();
 453
 454                 let mut rrs = parse_rr_stream(&proof).unwrap();
 455                 rrs.shuffle(&mut rand::rngs::OsRng);
 456                 let verified_rrs = verify_rr_stream(&rrs).unwrap();
 457                 assert!(verified_rrs.verified_rrs.len() >= 1);
 458
 459                 let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
 460                 assert!(verified_rrs.valid_from < now);
 461                 assert!(verified_rrs.expires > now);
 462         }
 463
 464         #[test]
 465         fn test_txt_query() {
 466                 let sockaddr = "8.8.8.8:53".to_socket_addrs().unwrap().next().unwrap();
 467                 let query_name = "matt.user._bitcoin-payment.mattcorallo.com.".try_into().unwrap();
 468                 let (proof, _) = build_txt_proof(sockaddr, &query_name).unwrap();
 469
 470                 let mut rrs = parse_rr_stream(&proof).unwrap();
 471                 rrs.shuffle(&mut rand::rngs::OsRng);
 472                 let verified_rrs = verify_rr_stream(&rrs).unwrap();
 473                 assert_eq!(verified_rrs.verified_rrs.len(), 1);
 474
 475                 let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
 476                 assert!(verified_rrs.valid_from < now);
 477                 assert!(verified_rrs.expires > now);
 478         }
 479
 480         #[test]
 481         fn test_cname_query() {
 482                 for resolver in ["1.1.1.1:53", "8.8.8.8:53", "9.9.9.9:53"] {
 483                         let sockaddr = resolver.to_socket_addrs().unwrap().next().unwrap();
 484                         let query_name = "cname_test.matcorallo.com.".try_into().unwrap();
 485                         let (proof, _) = build_txt_proof(sockaddr, &query_name).unwrap();
 486
 487                         let mut rrs = parse_rr_stream(&proof).unwrap();
 488                         rrs.shuffle(&mut rand::rngs::OsRng);
 489                         let verified_rrs = verify_rr_stream(&rrs).unwrap();
 490                         assert_eq!(verified_rrs.verified_rrs.len(), 2);
 491
 492                         let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
 493                         assert!(verified_rrs.valid_from < now);
 494                         assert!(verified_rrs.expires > now);
 495
 496                         let resolved_rrs = verified_rrs.resolve_name(&query_name);
 497                         assert_eq!(resolved_rrs.len(), 1);
 498                         if let RR::Txt(txt) = &resolved_rrs[0] {
 499                                 assert_eq!(txt.name.as_str(), "txt_test.matcorallo.com.");
 500                                 assert_eq!(txt.data, b"dnssec_prover_test");
 501                         } else { panic!(); }
 502                 }
 503         }
 504
 505         #[cfg(feature = "tokio")]
 506         use tokio_crate as tokio;
 507
 508         #[cfg(feature = "tokio")]
 509         #[tokio::test]
 510         async fn test_txt_query_async() {
 511                 let sockaddr = "8.8.8.8:53".to_socket_addrs().unwrap().next().unwrap();
 512                 let query_name = "matt.user._bitcoin-payment.mattcorallo.com.".try_into().unwrap();
 513                 let (proof, _) = build_txt_proof_async(sockaddr, &query_name).await.unwrap();
 514
 515                 let mut rrs = parse_rr_stream(&proof).unwrap();
 516                 rrs.shuffle(&mut rand::rngs::OsRng);
 517                 let verified_rrs = verify_rr_stream(&rrs).unwrap();
 518                 assert_eq!(verified_rrs.verified_rrs.len(), 1);
 519
 520                 let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
 521                 assert!(verified_rrs.valid_from < now);
 522                 assert!(verified_rrs.expires > now);
 523         }
 524
 525         #[cfg(feature = "tokio")]
 526         #[tokio::test]
 527         async fn test_cross_domain_cname_query_async() {
 528                 for resolver in ["1.1.1.1:53", "8.8.8.8:53", "9.9.9.9:53"] {
 529                         let sockaddr = resolver.to_socket_addrs().unwrap().next().unwrap();
 530                         let query_name = "wildcard.x_domain_cname_wild.matcorallo.com.".try_into().unwrap();
 531                         let (proof, _) = build_txt_proof_async(sockaddr, &query_name).await.unwrap();
 532
 533                         let mut rrs = parse_rr_stream(&proof).unwrap();
 534                         rrs.shuffle(&mut rand::rngs::OsRng);
 535                         let verified_rrs = verify_rr_stream(&rrs).unwrap();
 536                         assert_eq!(verified_rrs.verified_rrs.len(), 2);
 537
 538                         let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
 539                         assert!(verified_rrs.valid_from < now);
 540                         assert!(verified_rrs.expires > now);
 541
 542                         let resolved_rrs = verified_rrs.resolve_name(&query_name);
 543                         assert_eq!(resolved_rrs.len(), 1);
 544                         if let RR::Txt(txt) = &resolved_rrs[0] {
 545                                 assert_eq!(txt.name.as_str(), "matt.user._bitcoin-payment.mattcorallo.com.");
 546                                 assert!(txt.data.starts_with(b"bitcoin:"));
 547                         } else { panic!(); }
 548                 }
 549         }
 550 }